Commit Graph

57047 Commits

Author SHA1 Message Date
NeilBrown
97f68c6b02 SUNRPC: add 'struct cred *' to auth_cred and rpc_cred
The SUNRPC credential framework was put together before
Linux has 'struct cred'.  Now that we have it, it makes sense to
use it.
This first step just includes a suitable 'struct cred *' pointer
in every 'struct auth_cred' and almost every 'struct rpc_cred'.

The rpc_cred used for auth_null has a NULL 'struct cred *' as nothing
else really makes sense.

For rpc_cred, the pointer is reference counted.
For auth_cred it isn't.  struct auth_cred are either allocated on
the stack, in which case the thread owns a reference to the auth,
or are part of 'struct generic_cred' in which case gc_base owns the
reference, and "acred" shares it.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-12-19 13:52:44 -05:00
Pavel Tikhomirov
ac0aa5e843 nfs: fix comment to nfs_generic_pg_test which does the opposite
Please see comment to filelayout_pg_test for reference.

To: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: linux-nfs@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-12-19 13:52:44 -05:00
Olga Kornievskaia
069d5bf5ec NFSv4: cleanup remove unused nfs4_xdev_fs_type
commit e8f25e6d6d "NFS: Remove the NFS v4 xdev mount function"
removed the last use of this.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-12-19 13:52:44 -05:00
Theodore Ts'o
8a363970d1 ext4: avoid declaring fs inconsistent due to invalid file handles
If we receive a file handle, either from NFS or open_by_handle_at(2),
and it points at an inode which has not been initialized, and the file
system has metadata checksums enabled, we shouldn't try to get the
inode, discover the checksum is invalid, and then declare the file
system as being inconsistent.

This can be reproduced by creating a test file system via "mke2fs -t
ext4 -O metadata_csum /tmp/foo.img 8M", mounting it, cd'ing into that
directory, and then running the following program.

#define _GNU_SOURCE
#include <fcntl.h>

struct handle {
	struct file_handle fh;
	unsigned char fid[MAX_HANDLE_SZ];
};

int main(int argc, char **argv)
{
	struct handle h = {{8, 1 }, { 12, }};

	open_by_handle_at(AT_FDCWD, &h.fh, O_RDONLY);
	return 0;
}

Google-Bug-Id: 120690101
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
2018-12-19 12:29:13 -05:00
Theodore Ts'o
a805622a75 ext4: include terminating u32 in size of xattr entries when expanding inodes
In ext4_expand_extra_isize_ea(), we calculate the total size of the
xattr header, plus the xattr entries so we know how much of the
beginning part of the xattrs to move when expanding the inode extra
size.  We need to include the terminating u32 at the end of the xattr
entries, or else if there is uninitialized, non-zero bytes after the
xattr entries and before the xattr values, the list of xattr entries
won't be properly terminated.

Reported-by: Steve Graham <stgraham2000@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
2018-12-19 12:28:13 -05:00
Ronnie Sahlberg
271b9c0c80 smb3: Fix rmdir compounding regression to strict servers
Some servers require that the setinfo matches the exact size,
and in this case compounding changes introduced by
commit c2e0fe3f5a ("cifs: make rmdir() use compounding")
caused us to send 8 bytes (padded length) instead of 1 byte
(the size of the structure).  See MS-FSCC section 2.4.11.

Fixing this when we send a SET_INFO command for delete file
disposition, then ends up as an iov of a single byte but this
causes problems with SMB3 and encryption.

To avoid this, instead of creating a one byte iov for the disposition value
and then appending an additional iov with a 7 byte padding we now handle
this as a single 8 byte iov containing both the disposition byte as well as
the padding in one single buffer.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Paulo Alcantara <palcantara@suse.de>
2018-12-19 07:55:32 -06:00
Todd Kjos
80cd795630 binder: fix use-after-free due to ksys_close() during fdget()
44d8047f1d ("binder: use standard functions to allocate fds")
exposed a pre-existing issue in the binder driver.

fdget() is used in ksys_ioctl() as a performance optimization.
One of the rules associated with fdget() is that ksys_close() must
not be called between the fdget() and the fdput(). There is a case
where this requirement is not met in the binder driver which results
in the reference count dropping to 0 when the device is still in
use. This can result in use-after-free or other issues.

If userpace has passed a file-descriptor for the binder driver using
a BINDER_TYPE_FDA object, then kys_close() is called on it when
handling a binder_ioctl(BC_FREE_BUFFER) command. This violates
the assumptions for using fdget().

The problem is fixed by deferring the close using task_work_add(). A
new variant of __close_fd() was created that returns a struct file
with a reference. The fput() is deferred instead of using ksys_close().

Fixes: 44d8047f1d ("binder: use standard functions to allocate fds")
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Todd Kjos <tkjos@google.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-19 09:40:13 +01:00
Boris Brezillon
f366d3854e Core changes:
- Parse the 4BAIT SFDP section
 - Add a bunch of SPI NOR entries to the flash_info table
 - Add the concept of SFDP fixups and use it to fix a bug on MX25L25635F
 - A bunch of minor cleanups/comestic changes
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Merge tag 'spi-nor/for-4.21' of git://git.infradead.org/linux-mtd into mtd/next

Core changes:
- Parse the 4BAIT SFDP section
- Add a bunch of SPI NOR entries to the flash_info table
- Add the concept of SFDP fixups and use it to fix a bug on MX25L25635F
- A bunch of minor cleanups/comestic changes
2018-12-18 20:00:52 +01:00
Boris Brezillon
ccec4a4a4f Merge tag 'nand/for-4.21' of git://git.infradead.org/linux-mtd into mtd/next
NAND core changes:
- kernel-doc miscellaneous fixes.
- Third batch of fixes/cleanup to the raw NAND core impacting various
  controller drivers (ams-delta, marvell, fsmc, denali, tegra, vf610):
  * Stopping to pass mtd_info objects to internal functions
  * Reorganizing code to avoid forward declarations
  * Dropping useless test in nand_legacy_set_defaults()
  * Moving nand_exec_op() to internal.h
  * Adding nand_[de]select_target() helpers
  * Passing the CS line to be selected in struct nand_operation
  * Making ->select_chip() optional when ->exec_op() is implemented
  * Deprecating the ->select_chip() hook
  * Moving the ->exec_op() method to nand_controller_ops
  * Moving ->setup_data_interface() to nand_controller_ops
  * Deprecating the dummy_controller field
  * Fixing JEDEC detection
  * Providing a helper for polling GPIO R/B pin

Raw NAND chip drivers changes:
- Macronix:
  * Flagging 1.8V AC chips with a broken GET_FEATURES(TIMINGS)

Raw NAND controllers drivers changes:
- Ams-delta:
  * Fixing the error path
  * SPDX tag added
  * May be compiled with COMPILE_TEST=y
  * Conversion to ->exec_op() interface
  * Dropping .IOADDR_R/W use
  * Use GPIO API for data I/O
- Denali:
  * Removing denali_reset_banks()
  * Removing ->dev_ready() hook
  * Including <linux/bits.h> instead of <linux/bitops.h>
  * Changes to comply with the above fixes/cleanup done in the core.
- FSMC:
  * Adding an SPDX tag to replace the license text
  * Making conversion from chip to fsmc consistent
  * Fixing unchecked return value in fsmc_read_page_hwecc
  * Changes to comply with the above fixes/cleanup done in the core.
- Marvell:
  * Preventing timeouts on a loaded machine (fix)
  * Changes to comply with the above fixes/cleanup done in the core.
- OMAP2:
  * Pass the parent of pdev to dma_request_chan() (fix)
- R852:
  * Use generic DMA API
- sh_flctl:
  * Converting to SPDX identifiers
- Sunxi:
  * Write pageprog related opcodes to the right register: WCMD_SET (fix)
- Tegra:
  * Stop implementing ->select_chip()
- VF610:
  * Adding an SPDX tag to replace the license text
  * Changes to comply with the above fixes/cleanup done in the core.
- Various trivial/spelling/coding style fixes.

SPI-NAND drivers changes:
- Removing the depreacated mt29f_spinand driver from staging.
- Adding support for:
  * Toshiba TC58CVG2S0H
  * GigaDevice GD5FxGQ4xA
  * Winbond W25N01GV
2018-12-18 19:59:16 +01:00
Nick Bowler
a9d25bde1e xfs: Fix x32 ioctls when cmd numbers differ from ia32.
Several ioctl structs change size between native 32-bit (ia32) and x32
applications, because x32 follows the native 64-bit (amd64) integer
alignment rules and uses 64-bit time_t.  In these instances, the ioctl
number changes so userspace simply gets -ENOTTY.  This scenario can be
handled by simply adding more cases.

Looking at the different ioctls implemented here:

- All the ones marked 'No size or alignment issue on any arch' should
  presumably all be fine.

- All the ones under BROKEN_X86_ALIGNMENT are different under integer
  alignment rules.  Since x32 matches amd64 here, we just need both
  sets of cases handled.

- XFS_IOC_SWAPEXT has both integer alignment differences and time_t
  differences.  Since x32 matches amd64 here, we need to add a case
  which calls the native implementation.

- The remaining ioctls have neither 64-bit integers nor time_t, so
  x32 matches ia32 here and no change is required at this level.  The
  bulkstat ioctl implementations have some pointer chasing which is
  handled separately.

Signed-off-by: Nick Bowler <nbowler@draconx.ca>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-18 10:55:21 -08:00
Nick Bowler
7ca860e3c1 xfs: Fix bulkstat compat ioctls on x32 userspace.
The bulkstat family of ioctls are problematic on x32, because there is
a mixup of native 32-bit and 64-bit conventions.  The xfs_fsop_bulkreq
struct contains pointers and 32-bit integers so that matches the native
32-bit layout, and that means the ioctl implementation goes into the
regular compat path on x32.

However, the 'ubuffer' member of that struct in turn refers to either
struct xfs_inogrp or xfs_bstat (or an array of these).  On x32, those
structures match the native 64-bit layout.  The compat implementation
writes out the 32-bit version of these structures.  This is not the
expected format for x32 userspace, causing problems.

Fortunately the functions which actually output these xfs_inogrp and
xfs_bstat structures have an easy way to select which output format
is required, so we just need a little tweak to select the right format
on x32.

Signed-off-by: Nick Bowler <nbowler@draconx.ca>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-18 10:55:20 -08:00
Nick Bowler
c456d64449 xfs: Align compat attrlist_by_handle with native implementation.
While inspecting the ioctl implementations, I noticed that the compat
implementation of XFS_IOC_ATTRLIST_BY_HANDLE does not do exactly the
same thing as the native implementation.  Specifically, the "cursor"
does not appear to be written out to userspace on the compat path,
like it is on the native path.

This adjusts the compat implementation to copy out the cursor just
like the native implementation does.  The attrlist cursor does not
require any special compat handling.  This fixes xfstests xfs/269
on both IA-32 and x32 userspace, when running on an amd64 kernel.

Signed-off-by: Nick Bowler <nbowler@draconx.ca>
Fixes: 0facef7fb0 ("xfs: in _attrlist_by_handle, copy the cursor back to userspace")
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-18 10:55:20 -08:00
Javier Barrio
41c4f85cda quota: Lock s_umount in exclusive mode for Q_XQUOTA{ON,OFF} quotactls.
Commit 1fa5efe362 (ext4: Use generic helpers for quotaon
and quotaoff) made possible to call quotactl(Q_XQUOTAON/OFF) on ext4 filesystems
with sysfile quota support. This leads to calling dquot_enable/disable without s_umount
held in excl. mode, because quotactl_cmd_onoff checks only for Q_QUOTAON/OFF.

The following WARN_ON_ONCE triggers (in this case for dquot_enable, ext4, latest Linus' tree):

[  117.807056] EXT4-fs (dm-0): mounted filesystem with ordered data mode. Opts: quota,prjquota

[...]

[  155.036847] WARNING: CPU: 0 PID: 2343 at fs/quota/dquot.c:2469 dquot_enable+0x34/0xb9
[  155.036851] Modules linked in: quota_v2 quota_tree ipv6 af_packet joydev mousedev psmouse serio_raw pcspkr i2c_piix4 intel_agp intel_gtt e1000 ttm drm_kms_helper drm agpgart fb_sys_fops syscopyarea sysfillrect sysimgblt i2c_core input_leds kvm_intel kvm irqbypass qemu_fw_cfg floppy evdev parport_pc parport button crc32c_generic dm_mod ata_generic pata_acpi ata_piix libata loop ext4 crc16 mbcache jbd2 usb_storage usbcore sd_mod scsi_mod
[  155.036901] CPU: 0 PID: 2343 Comm: qctl Not tainted 4.20.0-rc6-00025-gf5d582777bcb #9
[  155.036903] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[  155.036911] RIP: 0010:dquot_enable+0x34/0xb9
[  155.036915] Code: 41 56 41 55 41 54 55 53 4c 8b 6f 28 74 02 0f 0b 4d 8d 7d 70 49 89 fc 89 cb 41 89 d6 89 f5 4c 89 ff e8 23 09 ea ff 85 c0 74 0a <0f> 0b 4c 89 ff e8 8b 09 ea ff 85 db 74 6a 41 8b b5 f8 00 00 00 0f
[  155.036918] RSP: 0018:ffffb09b00493e08 EFLAGS: 00010202
[  155.036922] RAX: 0000000000000001 RBX: 0000000000000008 RCX: 0000000000000008
[  155.036924] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff9781b67cd870
[  155.036926] RBP: 0000000000000002 R08: 0000000000000000 R09: 61c8864680b583eb
[  155.036929] R10: ffffb09b00493e48 R11: ffffffffff7ce7d4 R12: ffff9781b7ee8d78
[  155.036932] R13: ffff9781b67cd800 R14: 0000000000000004 R15: ffff9781b67cd870
[  155.036936] FS:  00007fd813250b88(0000) GS:ffff9781ba000000(0000) knlGS:0000000000000000
[  155.036939] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  155.036942] CR2: 00007fd812ff61d6 CR3: 000000007c882000 CR4: 00000000000006b0
[  155.036951] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  155.036953] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  155.036955] Call Trace:
[  155.037004]  dquot_quota_enable+0x8b/0xd0
[  155.037011]  kernel_quotactl+0x628/0x74e
[  155.037027]  ? do_mprotect_pkey+0x2a6/0x2cd
[  155.037034]  __x64_sys_quotactl+0x1a/0x1d
[  155.037041]  do_syscall_64+0x55/0xe4
[  155.037078]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  155.037105] RIP: 0033:0x7fd812fe1198
[  155.037109] Code: 02 77 0d 48 89 c1 48 c1 e9 3f 75 04 48 8b 04 24 48 83 c4 50 5b c3 48 83 ec 08 49 89 ca 48 63 d2 48 63 ff b8 b3 00 00 00 0f 05 <48> 89 c7 e8 c1 eb ff ff 5a c3 48 63 ff b8 bb 00 00 00 0f 05 48 89
[  155.037112] RSP: 002b:00007ffe8cd7b050 EFLAGS: 00000206 ORIG_RAX: 00000000000000b3
[  155.037116] RAX: ffffffffffffffda RBX: 00007ffe8cd7b148 RCX: 00007fd812fe1198
[  155.037119] RDX: 0000000000000000 RSI: 00007ffe8cd7cea9 RDI: 0000000000580102
[  155.037121] RBP: 00007ffe8cd7b0f0 R08: 000055fc8eba8a9d R09: 0000000000000000
[  155.037124] R10: 00007ffe8cd7b074 R11: 0000000000000206 R12: 00007ffe8cd7b168
[  155.037126] R13: 000055fc8eba8897 R14: 0000000000000000 R15: 0000000000000000
[  155.037131] ---[ end trace 210f864257175c51 ]---

and then the syscall proceeds without s_umount locking.

This patch locks the superblock ->s_umount sem. in exclusive mode for all Q_XQUOTAON/OFF
quotactls too in addition to Q_QUOTAON/OFF.

AFAICT, other than ext4, only xfs and ocfs2 are affected by this change.
The VFS will now call in xfs_quota_* functions with s_umount held, which wasn't the case
before. This looks good to me but I can not say for sure. Ext4 and ocfs2 where already
beeing called with s_umount exclusive via quota_quotaon/off which is basically the same.

Signed-off-by: Javier Barrio <javier.barrio.mart@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2018-12-18 18:29:15 +01:00
Bob Peterson
bc0205612b gfs2: take jdata unstuff into account in do_grow
Before this patch, function do_grow would not reserve enough journal
blocks in the transaction to unstuff jdata files while growing them.
This patch adds the logic to add one more block if the file to grow
is jdata.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-12-18 10:49:02 -06:00
Jens Axboe
875736bb3f aio: abstract out io_event filler helper
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:59 -07:00
Jens Axboe
88a6f18b95 aio: split out iocb copy from io_submit_one()
In preparation of handing in iocbs in a different fashion as well. Also
make it clear that the iocb being passed in isn't modified, by marking
it const throughout.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:59 -07:00
Jens Axboe
71ebc6fef0 aio: use iocb_put() instead of open coding it
Replace the percpu_ref_put() + kmem_cache_free() with a call to
iocb_put() instead.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:58 -07:00
Jens Axboe
a79d40e9b0 aio: only use blk plugs for > 2 depth submissions
Plugging is meant to optimize submission of a string of IOs, if we don't
have more than 2 being submitted, don't bother setting up a plug.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:58 -07:00
Jens Axboe
2bc4ca9bb6 aio: don't zero entire aio_kiocb aio_get_req()
It's 192 bytes, fairly substantial. Most items don't need to be cleared,
especially not upfront. Clear the ones we do need to clear, and leave
the other ones for setup when the iocb is prepared and submitted.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:58 -07:00
Christoph Hellwig
432c79978c aio: separate out ring reservation from req allocation
This is in preparation for certain types of IO not needing a ring
reserveration.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:58 -07:00
Jens Axboe
bc9bff6162 aio: use assigned completion handler
We know this is a read/write request, but in preparation for
having different kinds of those, ensure that we call the assigned
handler instead of assuming it's aio_complete_rq().

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:58 -07:00
Jens Axboe
4b92543282 Merge branch 'for-4.21/block' into for-4.21/aio
* for-4.21/block: (351 commits)
  blk-mq: enable IO poll if .nr_queues of type poll > 0
  blk-mq: change blk_mq_queue_busy() to blk_mq_queue_inflight()
  blk-mq: skip zero-queue maps in blk_mq_map_swqueue
  block: fix blk-iolatency accounting underflow
  blk-mq: fix dispatch from sw queue
  block: mq-deadline: Fix write completion handling
  nvme-pci: don't share queue maps
  blk-mq: only dispatch to non-defauly queue maps if they have queues
  blk-mq: export hctx->type in debugfs instead of sysfs
  blk-mq: fix allocation for queue mapping table
  blk-wbt: export internal state via debugfs
  blk-mq-debugfs: support rq_qos
  block: update sysfs documentation
  block: loop: check error using IS_ERR instead of IS_ERR_OR_NULL in loop_add()
  aoe: add __exit annotation
  block: clear REQ_HIPRI if polling is not supported
  blk-mq: replace and kill blk_mq_request_issue_directly
  blk-mq: issue directly with bypass 'false' in blk_mq_sched_insert_requests
  blk-mq: refactor the code of issue request directly
  block: remove the bio_integrity_advance export
  ...
2018-12-18 08:29:53 -07:00
Arnd Bergmann
d651d1607f vfs: replace current_kernel_time64 with ktime equivalent
current_time is the last remaining caller of current_kernel_time64(),
which is a wrapper around ktime_get_coarse_real_ts64().  This calls the
latter directly for consistency with the rest of the kernel that is moving
to the ktime_get_ family of time accessors, as now documented in
Documentation/core-api/timekeeping.rst.

An open questions is whether we may want to actually call the more
accurate ktime_get_real_ts64() for file systems that save high-resolution
timestamps in their on-disk format.  This would add a small overhead to
each update of the inode stamps but lead to inode timestamps to actually
have a usable resolution better than one jiffy (1 to 10 milliseconds
normally).  Experiments on a variety of hardware platforms show a typical
time of around 100 CPU cycles to read the cycle counter and calculate the
accurate time from that.  On old platforms without a cycle counter, this
can be signiciantly higher, up to several microseconds to access a
hardware clock, but those have become very rare by now.

I traced the original addition of the current_kernel_time() call to set
the nanosecond fields back to linux-2.5.48, where Andi Kleen added a patch
with subject "nanosecond stat timefields".  Andi explains that the
motivation was to introduce as little overhead as possible back then.  At
this time, reading the clock hardware was also more expensive when most
architectures did not have a cycle counter.

One side effect of having more accurate inode timestamp would be having to
write out the inode every time that mtime/ctime/atime get touched on most
systems, whereas many file systems today only write it when the timestamps
have changed, i.e.  at most once per jiffy unless something else changes
as well.  That change would certainly be noticed in some workloads, which
is enough reason to not do it without a good reason, regardless of the
cost of reading the time.

One thing we could still consider however would be to round the timestamps
from current_time() to multiples of NSEC_PER_JIFFY, e.g.  full
milliseconds rather than having six or seven meaningless but confusing
digits at the end of the timestamp.

Link: http://lkml.kernel.org/r/20180726130820.4174359-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-18 16:13:05 +01:00
Al Viro
26cb5a328c exofs_mount(): fix leaks on failure exits
... and don't abuse mount_nodev(), while we are at it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: David Howells <dhowells@redhat.com>
2018-12-17 18:36:33 -05:00
Andrea Gelmini
52042d8e82 btrfs: Fix typos in comments and strings
The typos accumulate over time so once in a while time they get fixed in
a large patch.

Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:50 +01:00
Johannes Thumshirn
1690dd41e0 btrfs: improve error handling of btrfs_add_link
In the error handling block, err holds the return value of either
btrfs_del_root_ref() or btrfs_del_inode_ref() but it hasn't been checked
since it's introduction with commit fe66a05a06 (Btrfs: improve error
handling for btrfs_insert_dir_item callers) in 2012.

If the error handling in the error handling fails, there's not much left
to do and the abort either happened earlier in the callees or is
necessary here.

So if one of btrfs_del_root_ref() or btrfs_del_inode_ref() failed, abort
the transaction, but still return the original code of the failure
stored in 'ret' as this will be reported to the user.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:50 +01:00
Filipe Manana
34a28e3d77 Btrfs: use generic_remap_file_range_prep() for cloning and deduplication
Since cloning and deduplication are no longer Btrfs specific operations, we
now have generic code to handle parameter validation, compare file ranges
used for deduplication, clear capabilities when cloning, etc. This change
makes Btrfs use it, eliminating a lot of code in Btrfs and also fixing a
few bugs, such as:

1) When cloning, the destination file's capabilities were not dropped
   (the fstest generic/513 tests this);

2) We were not checking if the destination file is immutable;

3) Not checking if either the source or destination files are swap
   files (swap file support is coming soon for Btrfs);

4) System limits were not checked (resource limits and O_LARGEFILE).

Note that the generic helper generic_remap_file_range_prep() does start
and waits for writeback by calling filemap_write_and_wait_range(), however
that is not enough for Btrfs for two reasons:

1) With compression, we need to start writeback twice in order to get the
   pages marked for writeback and ordered extents created;

2) filemap_write_and_wait_range() (and all its other variants) only waits
   for the IO to complete, but we need to wait for the ordered extents to
   finish, so that when we do the actual reflinking operations the file
   extent items are in the fs tree. This is also important due to the fact
   that the generic helper, for the deduplication case, compares the
   contents of the pages in the requested range, which might require
   reading extents from disk in the very unlikely case that pages get
   invalidated after writeback finishes (so the file extent items must be
   up to date in the fs tree).

Since these reasons are specific to Btrfs we have to do it in the Btrfs
code before calling generic_remap_file_range_prep(). This also results
in a simpler way of dealing with existing delalloc in the source/target
ranges, specially for the deduplication case where we used to lock all
the pages first and then if we found any dealloc for the range, or
ordered extent, we would unlock the pages trigger writeback and wait for
ordered extents to complete, then lock all the pages again and check if
deduplication can be done. So now we get a simpler approach: lock the
inodes, then trigger writeback and then wait for ordered extents to
complete.

So make btrfs use generic_remap_file_range_prep() (XFS and OCFS2 use it)
to eliminate duplicated code, fix a few bugs and benefit from future bug
fixes done there - for example the recent clone and dedupe bugs involving
reflinking a partial EOF block got a counterpart fix in the generic
helper, since it affected all filesystems supporting these operations,
so we no longer need special checks in Btrfs for them.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:50 +01:00
Nikolay Borisov
61ed3a144a btrfs: Refactor main loop in extent_readpages
extent_readpages processes all pages in the readlist in batches of 16,
this is implemented by a single for loop but thanks to an if condition
the loop does 2 things based on whether we've filled the batch or not.
Additionally due to the structure of the code there is an additional
check which deals with partial batches.

Streamline all of this by explicitly using two loops. The outter one is
used to process all pages while the inner one just fills in the batch
of 16 (currently). Due to this new structure the code guarantees that
all pages are processed in the loop hence the code to deal with any
leftovers is eliminated.

This also enable the compiler to inline __extent_readpages:

	./scripts/bloat-o-meter fs/btrfs/extent_io.o extent_io.for

	add/remove: 0/1 grow/shrink: 1/0 up/down: 660/-820 (-160)
	Function                                     old     new   delta
	extent_readpages                             476    1136    +660
	__extent_readpages                           820       -    -820
	Total: Before=44315, After=44155, chg -0.36%

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:49 +01:00
Nikolay Borisov
15c8276302 btrfs: Remove 1st shrink/grow phase from balance
The first step of the rebalance process ensures there is 1MiB free on
each device. This number seems rather small. And in fact when talking to
the original authors their opinions were:

"man that's a little bonkers"
"i don't think we even need that code anymore"
"I think it was there to make sure we had room for the blank 1M at the
beginning. I bet it goes all the way back to v0"
"we just don't need any of that tho, i say we just delete it"

Clearly, this piece of code has lost its original intent throughout the
years. It doesn't really bring any real practical benefits to the
relocation process.

Additionally, this patch makes the balance process more lightweight by
removing a pair of shrink/grow operations which are rather expensive for
heavily populated filesystems. This is mainly due to shrink requiring
relocating block groups, involving heavy use of the btree.

The intermediate shrink/grow can fail and leave the filesystem in a
middle state that would need to be changed back by the user.

Suggested-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:49 +01:00
Filipe Manana
be6821f82c Btrfs: send, fix race with transaction commits that create snapshots
If we create a snapshot of a snapshot currently being used by a send
operation, we can end up with send failing unexpectedly (returning
-ENOENT error to user space for example). The following diagram shows
how this happens.

            CPU 1                                   CPU2                                CPU3

 btrfs_ioctl_send()
  (...)
                                     create_snapshot()
                                      -> creates snapshot of a
                                         root used by the send
                                         task
                                      btrfs_commit_transaction()
                                       create_pending_snapshot()
  __get_inode_info()
   btrfs_search_slot()
    btrfs_search_slot_get_root()
     down_read commit_root_sem

     get reference on eb of the
     commit root
      -> eb with bytenr == X

     up_read commit_root_sem

                                        btrfs_cow_block(root node)
                                         btrfs_free_tree_block()
                                          -> creates delayed ref to
                                             free the extent

                                       btrfs_run_delayed_refs()
                                        -> runs the delayed ref,
                                           adds extent to
                                           fs_info->pinned_extents

                                       btrfs_finish_extent_commit()
                                        unpin_extent_range()
                                         -> marks extent as free
                                            in the free space cache

                                      transaction commit finishes

                                                                       btrfs_start_transaction()
                                                                        (...)
                                                                        btrfs_cow_block()
                                                                         btrfs_alloc_tree_block()
                                                                          btrfs_reserve_extent()
                                                                           -> allocates extent at
                                                                              bytenr == X
                                                                          btrfs_init_new_buffer(bytenr X)
                                                                           btrfs_find_create_tree_block()
                                                                            alloc_extent_buffer(bytenr X)
                                                                             find_extent_buffer(bytenr X)
                                                                              -> returns existing eb,
                                                                                 which the send task got

                                                                        (...)
                                                                         -> modifies content of the
                                                                            eb with bytenr == X

    -> uses an eb that now
       belongs to some other
       tree and no more matches
       the commit root of the
       snapshot, resuts will be
       unpredictable

The consequences of this race can be various, and can lead to searches in
the commit root performed by the send task failing unexpectedly (unable to
find inode items, returning -ENOENT to user space, for example) or not
failing because an inode item with the same number was added to the tree
that reused the metadata extent, in which case send can behave incorrectly
in the worst case or just fail later for some reason.

Fix this by performing a copy of the commit root's extent buffer when doing
a search in the context of a send operation.

CC: stable@vger.kernel.org # 4.4.x: 1fc28d8e2e: Btrfs: move get root out of btrfs_search_slot to a helper
CC: stable@vger.kernel.org # 4.4.x: f9ddfd0592: Btrfs: remove unused check of skip_locking
CC: stable@vger.kernel.org # 4.4.x
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:49 +01:00
Filipe Manana
827aa18e7b Btrfs: use nofs context when initializing security xattrs to avoid deadlock
When initializing the security xattrs, we are holding a transaction handle
therefore we need to use a GFP_NOFS context in order to avoid a deadlock
with reclaim in case it's triggered.

Fixes: 39a27ec100 ("btrfs: use GFP_KERNEL for xattr and acl allocations")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:49 +01:00
Josef Bacik
0568e82dbe btrfs: run delayed items before dropping the snapshot
With my delayed refs patches in place we started seeing a large amount
of aborts in __btrfs_free_extent:

 BTRFS error (device sdb1): unable to find ref byte nr 91947008 parent 0 root 35964  owner 1 offset 0
 Call Trace:
  ? btrfs_merge_delayed_refs+0xaf/0x340
  __btrfs_run_delayed_refs+0x6ea/0xfc0
  ? btrfs_set_path_blocking+0x31/0x60
  btrfs_run_delayed_refs+0xeb/0x180
  btrfs_commit_transaction+0x179/0x7f0
  ? btrfs_check_space_for_delayed_refs+0x30/0x50
  ? should_end_transaction.isra.19+0xe/0x40
  btrfs_drop_snapshot+0x41c/0x7c0
  btrfs_clean_one_deleted_snapshot+0xb5/0xd0
  cleaner_kthread+0xf6/0x120
  kthread+0xf8/0x130
  ? btree_invalidatepage+0x90/0x90
  ? kthread_bind+0x10/0x10
  ret_from_fork+0x35/0x40

This was because btrfs_drop_snapshot depends on the root not being
modified while it's dropping the snapshot.  It will unlock the root node
(and really every node) as it walks down the tree, only to re-lock it
when it needs to do something.  This is a problem because if we modify
the tree we could cow a block in our path, which frees our reference to
that block.  Then once we get back to that shared block we'll free our
reference to it again, and get ENOENT when trying to lookup our extent
reference to that block in __btrfs_free_extent.

This is ultimately happening because we have delayed items left to be
processed for our deleted snapshot _after_ all of the inodes are closed
for the snapshot.  We only run the delayed inode item if we're deleting
the inode, and even then we do not run the delayed insertions or delayed
removals.  These can be run at any point after our final inode does its
last iput, which is what triggers the snapshot deletion.  We can end up
with the snapshot deletion happening and then have the delayed items run
on that file system, resulting in the above problem.

This problem has existed forever, however my patches made it much easier
to hit as I wake up the cleaner much more often to deal with delayed
iputs, which made us more likely to start the snapshot dropping work
before the transaction commits, which is when the delayed items would
generally be run.  Before, generally speaking, we would run the delayed
items, commit the transaction, and wakeup the cleaner thread to start
deleting snapshots, which means we were less likely to hit this problem.
You could still hit it if you had multiple snapshots to be deleted and
ended up with lots of delayed items, but it was definitely harder.

Fix for now by simply running all the delayed items before starting to
drop the snapshot.  We could make this smarter in the future by making
the delayed items per-root, and then simply drop any delayed items for
roots that we are going to delete.  But for now just a quick and easy
solution is the safest.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:49 +01:00
Josef Bacik
83354f0772 btrfs: catch cow on deleting snapshots
When debugging some weird extent reference bug I suspected that we were
changing a snapshot while we were deleting it, which could explain my
bug.  This was indeed what was happening, and this patch helped me
verify my theory.  It is never correct to modify the snapshot once it's
being deleted, so mark the root when we are deleting it and make sure we
complain about it when it happens.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:48 +01:00
Qu Wenruo
01e0da4885 btrfs: extent-tree: cleanup one-shot usage of @blocksize in do_walk_down
@blocksize variable in do_walk_down() is only used once, really no need
to declare it.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:48 +01:00
Filipe Manana
7c3c7cb99c Btrfs: scrub, move setup of nofs contexts higher in the stack
Since scrub workers only do memory allocation with GFP_KERNEL when they
need to perform repair, we can move the recent setup of the nofs context
up to scrub_handle_errored_block() instead of setting it up down the call
chain at insert_full_stripe_lock() and scrub_add_page_to_wr_bio(),
removing some duplicate code and comment. So the only paths for which a
scrub worker can do memory allocations using GFP_KERNEL are the following:

 scrub_bio_end_io_worker()
   scrub_block_complete()
     scrub_handle_errored_block()
       lock_full_stripe()
         insert_full_stripe_lock()
           -> kmalloc with GFP_KERNEL

  scrub_bio_end_io_worker()
    scrub_block_complete()
      scrub_handle_errored_block()
        scrub_write_page_to_dev_replace()
          scrub_add_page_to_wr_bio()
            -> kzalloc with GFP_KERNEL

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:48 +01:00
David Sterba
0e94c4f45d btrfs: scrub: move scrub_setup_ctx allocation out of device_list_mutex
The scrub context is allocated with GFP_KERNEL and called from
btrfs_scrub_dev under the fs_info::device_list_mutex. This is not safe
regarding reclaim that could try to flush filesystem data in order to
get the memory. And the device_list_mutex is held during superblock
commit, so this would cause a lockup.

Move the alocation and initialization before any changes that require
the mutex.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:48 +01:00
David Sterba
92f7ba434f btrfs: scrub: pass fs_info to scrub_setup_ctx
We can pass fs_info directly as this is the only member of btrfs_device
that's bing used inside scrub_setup_ctx.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:48 +01:00
Josef Bacik
28bad21257 btrfs: fix truncate throttling
We have a bunch of magic to make sure we're throttling delayed refs when
truncating a file.  Now that we have a delayed refs rsv and a mechanism
for refilling that reserve simply use that instead of all of this magic.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:47 +01:00
Josef Bacik
db2462a6ad btrfs: don't run delayed refs in the end transaction logic
Over the years we have built up a lot of infrastructure to keep delayed
refs in check, mostly by running them at btrfs_end_transaction() time.
We have a lot of different maths we do to figure out how much, if we
should do it inline or async, etc.  This existed because we had no
feedback mechanism to force the flushing of delayed refs when they
became a problem.  However with the enospc flushing infrastructure in
place for flushing delayed refs when they put too much pressure on the
enospc system we have this problem solved.  Rip out all of this code as
it is no longer needed.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:47 +01:00
Josef Bacik
64403612b7 btrfs: rework btrfs_check_space_for_delayed_refs
Now with the delayed_refs_rsv we can now know exactly how much pending
delayed refs space we need.  This means we can drastically simplify
btrfs_check_space_for_delayed_refs by simply checking how much space we
have reserved for the global rsv (which acts as a spill over buffer) and
the delayed refs rsv.  If our total size is beyond that amount then we
know it's time to commit the transaction and stop any more delayed refs
from being generated.

With the introduction of dealyed_refs_rsv infrastructure, namely
btrfs_update_delayed_refs_rsv we now know exactly how much pending
delayed refs space is required.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:47 +01:00
Josef Bacik
413df7252d btrfs: add new flushing states for the delayed refs rsv
A nice thing we gain with the delayed refs rsv is the ability to flush
the delayed refs on demand to deal with enospc pressure.  Add states to
flush delayed refs on demand, and this will allow us to remove a lot of
ad-hoc work around checking to see if we should commit the transaction
to run our delayed refs.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:47 +01:00
Josef Bacik
4c8edbc75c btrfs: update may_commit_transaction to use the delayed refs rsv
Any space used in the delayed_refs_rsv will be freed up by a transaction
commit, so instead of just counting the pinned space we also need to
account for any space in the delayed_refs_rsv when deciding if it will
make a different to commit the transaction to satisfy our space
reservation.  If we have enough bytes to satisfy our reservation ticket
then we are good to go, otherwise subtract out what space we would gain
back by committing the transaction and compare that against the pinned
space to make our decision.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:47 +01:00
Josef Bacik
ba2c4d4e3b btrfs: introduce delayed_refs_rsv
Traditionally we've had voodoo in btrfs to account for the space that
delayed refs may take up by having a global_block_rsv.  This works most
of the time, except when it doesn't.  We've had issues reported and seen
in production where sometimes the global reserve is exhausted during
transaction commit before we can run all of our delayed refs, resulting
in an aborted transaction.  Because of this voodoo we have equally
dubious flushing semantics around throttling delayed refs which we often
get wrong.

So instead give them their own block_rsv.  This way we can always know
exactly how much outstanding space we need for delayed refs.  This
allows us to make sure we are constantly filling that reservation up
with space, and allows us to put more precise pressure on the enospc
system.  Instead of doing math to see if its a good time to throttle,
the normal enospc code will be invoked if we have a lot of delayed refs
pending, and they will be run via the normal flushing mechanism.

For now the delayed_refs_rsv will hold the reservations for the delayed
refs, the block group updates, and deleting csums.  We could have a
separate rsv for the block group updates, but the csum deletion stuff is
still handled via the delayed_refs so that will stay there.

Historical background:

The global reserve has grown to cover everything we don't reserve space
explicitly for, and we've grown a lot of weird ad-hoc heuristics to know
if we're running short on space and when it's time to force a commit.  A
failure rate of 20-40 file systems when we run hundreds of thousands of
them isn't super high, but cleaning up this code will make things less
ugly and more predictible.

Thus the delayed refs rsv.  We always know how many delayed refs we have
outstanding, and although running them generates more we can use the
global reserve for that spill over, which fits better into it's desired
use than a full blown reservation.  This first approach is to simply
take how many times we're reserving space for and multiply that by 2 in
order to save enough space for the delayed refs that could be generated.
This is a niave approach and will probably evolve, but for now it works.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com> # high-level review
[ added background notes from the cover letter ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:46 +01:00
Josef Bacik
158ffa364b btrfs: only track ref_heads in delayed_ref_updates
We use this number to figure out how many delayed refs to run, but
__btrfs_run_delayed_refs really only checks every time we need a new
delayed ref head, so we always run at least one ref head completely no
matter what the number of items on it.  Fix the accounting to only be
adjusted when we add/remove a ref head.

In addition to using this number to limit the number of delayed refs
run, a future patch is also going to use it to calculate the amount of
space required for delayed refs space reservation.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:46 +01:00
Josef Bacik
bedc661760 btrfs: cleanup extent_op handling
The cleanup_extent_op function actually would run the extent_op if it
needed running, which made the name sort of a misnomer.  Change it to
run_and_cleanup_extent_op, and move the actual cleanup work to
cleanup_extent_op so it can be used by check_ref_cleanup() in order to
unify the extent op handling.

Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:46 +01:00
Josef Bacik
07c47775f4 btrfs: add cleanup_ref_head_accounting helper
We were missing some quota cleanups in check_ref_cleanup, so break the
ref head accounting cleanup into a helper and call that from both
check_ref_cleanup and cleanup_ref_head.  This will hopefully ensure that
we don't screw up accounting in the future for other things that we add.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:46 +01:00
Josef Bacik
d7baffdaf9 btrfs: add btrfs_delete_ref_head helper
We do this dance in cleanup_ref_head and check_ref_cleanup, unify it
into a helper and cleanup the calling functions.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:46 +01:00
Johannes Thumshirn
fdb1e12180 btrfs: use PAGE_ALIGNED instead of open-coding it
When using a 'var & (PAGE_SIZE - 1)' construct one is checking for a page
alignment and thus should use the PAGE_ALIGNED() macro instead of
open-coding it.

Convert all open-coded occurrences of PAGE_ALIGNED().

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:45 +01:00
Johannes Thumshirn
7073017aeb btrfs: use offset_in_page instead of open-coding it
Constructs like 'var & (PAGE_SIZE - 1)' or 'var & ~PAGE_MASK' can denote an
offset into a page.

So replace them by the offset_in_page() macro instead of open-coding it if
they're not used as an alignment check.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:45 +01:00
David Sterba
cb5583dd52 btrfs: dev-replace: open code trivial locking helpers
The dev-replace locking functions are now trivial wrappers around rw
semaphore that can be used directly everywhere. No functional change.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:45 +01:00
David Sterba
53176dde0a btrfs: dev-replace: remove custom read/write blocking scheme
After the rw semaphore has been added, the custom blocking using
::blocking_readers and ::read_lock_wq is redundant.

The blocking logic in __btrfs_map_block is replaced by extending the
time the semaphore is held, that has the same blocking effect on writes
as the previous custom scheme that waited until ::blocking_readers was
zero.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:45 +01:00
David Sterba
129827e300 btrfs: dev-replace: swich locking to rw semaphore
This is the first part of removing the custom locking and waiting scheme
used for device replace. It was probably copied from extent buffer
locking, but there's nothing that would require more than is provided by
the common locking primitives.

The rw spinlock protects waiting tasks counter in case of incompatible
locks and the waitqueue. Same as rw semaphore.

This patch only switches the locking primitive, for better
bisectability.  There should be no functional change other than the
overhead of the locking and potential sleeping instead of spinning when
the lock is contended.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:44 +01:00
David Sterba
ceb21a8db4 btrfs: reada: reorder dev-replace locks before radix tree preload
The device-replace read lock is going to use rw semaphore in followup
commits. The semaphore might sleep which is not possible in the radix
tree preload section. The lock nesting is now:

* device replace
  * radix tree preload
    * readahead spinlock

Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:44 +01:00
Nikolay Borisov
d1051d6ebf btrfs: Fix error handling in btrfs_cleanup_ordered_extents
Running btrfs/124 in a loop hung up on me sporadically with the
following call trace:

	btrfs           D    0  5760   5324 0x00000000
	Call Trace:
	 ? __schedule+0x243/0x800
	 schedule+0x33/0x90
	 btrfs_start_ordered_extent+0x10c/0x1b0 [btrfs]
	 ? wait_woken+0xa0/0xa0
	 btrfs_wait_ordered_range+0xbb/0x100 [btrfs]
	 btrfs_relocate_block_group+0x1ff/0x230 [btrfs]
	 btrfs_relocate_chunk+0x49/0x100 [btrfs]
	 btrfs_balance+0xbeb/0x1740 [btrfs]
	 btrfs_ioctl_balance+0x2ee/0x380 [btrfs]
	 btrfs_ioctl+0x1691/0x3110 [btrfs]
	 ? lockdep_hardirqs_on+0xed/0x180
	 ? __handle_mm_fault+0x8e7/0xfb0
	 ? _raw_spin_unlock+0x24/0x30
	 ? __handle_mm_fault+0x8e7/0xfb0
	 ? do_vfs_ioctl+0xa5/0x6e0
	 ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs]
	 do_vfs_ioctl+0xa5/0x6e0
	 ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe
	 ksys_ioctl+0x3a/0x70
	 __x64_sys_ioctl+0x16/0x20
	 do_syscall_64+0x60/0x1b0
	 entry_SYSCALL_64_after_hwframe+0x49/0xbe

This happens because during page writeback it's valid for
writepage_delalloc to instantiate a delalloc range which doesn't belong
to the page currently being written back.

The reason this case is valid is due to find_lock_delalloc_range
returning any available range after the passed delalloc_start and
ignoring whether the page under writeback is within that range.

In turn ordered extents (OE) are always created for the returned range
from find_lock_delalloc_range. If, however, a failure occurs while OE
are being created then the clean up code in btrfs_cleanup_ordered_extents
will be called.

Unfortunately the code in btrfs_cleanup_ordered_extents doesn't consider
the case of such 'foreign' range being processed and instead it always
assumes that the range OE are created for belongs to the page. This
leads to the first page of such foregin range to not be cleaned up since
it's deliberately missed and skipped by the current cleaning up code.

Fix this by correctly checking whether the current page belongs to the
range being instantiated and if so adjsut the range parameters passed
for cleaning up. If it doesn't, then just clean the whole OE range
directly.

Fixes: 524272607e ("btrfs: Handle delalloc error correctly to avoid ordered extent hang")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:44 +01:00
Lu Fengqi
3522e90301 btrfs: remove always true if branch in find_delalloc_range
The @found is always false when it comes to the if branch. Besides, the
bool type is more suitable for @found. Change the return value of the
function and its caller to bool as well.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:44 +01:00
Lu Fengqi
27a7ff554e btrfs: skip file_extent generation check for free_space_inode in run_delalloc_nocow
The test case btrfs/001 with inode_cache mount option will encounter the
following warning:

  WARNING: CPU: 1 PID: 23700 at fs/btrfs/inode.c:956 cow_file_range.isra.19+0x32b/0x430 [btrfs]
  CPU: 1 PID: 23700 Comm: btrfs Kdump: loaded Tainted: G        W  O      4.20.0-rc4-custom+ #30
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  RIP: 0010:cow_file_range.isra.19+0x32b/0x430 [btrfs]
  Call Trace:
   ? free_extent_buffer+0x46/0x90 [btrfs]
   run_delalloc_nocow+0x455/0x900 [btrfs]
   btrfs_run_delalloc_range+0x1a7/0x360 [btrfs]
   writepage_delalloc+0xf9/0x150 [btrfs]
   __extent_writepage+0x125/0x3e0 [btrfs]
   extent_write_cache_pages+0x1b6/0x3e0 [btrfs]
   ? __wake_up_common_lock+0x63/0xc0
   extent_writepages+0x50/0x80 [btrfs]
   do_writepages+0x41/0xd0
   ? __filemap_fdatawrite_range+0x9e/0xf0
   __filemap_fdatawrite_range+0xbe/0xf0
   btrfs_fdatawrite_range+0x1b/0x50 [btrfs]
   __btrfs_write_out_cache+0x42c/0x480 [btrfs]
   btrfs_write_out_ino_cache+0x84/0xd0 [btrfs]
   btrfs_save_ino_cache+0x551/0x660 [btrfs]
   commit_fs_roots+0xc5/0x190 [btrfs]
   btrfs_commit_transaction+0x2bf/0x8d0 [btrfs]
   btrfs_mksubvol+0x48d/0x4d0 [btrfs]
   btrfs_ioctl_snap_create_transid+0x170/0x180 [btrfs]
   btrfs_ioctl_snap_create_v2+0x124/0x180 [btrfs]
   btrfs_ioctl+0x123f/0x3030 [btrfs]

The file extent generation of the free space inode is equal to the last
snapshot of the file root, so the inode will be passed to cow_file_rage.
But the inode was created and its extents were preallocated in
btrfs_save_ino_cache, there are no cow copies on disk.

The preallocated extent is not yet in the extent tree, and
btrfs_cross_ref_exist will ignore the -ENOENT returned by
check_committed_ref, so we can directly write the inode to the disk.

Fixes: 78d4295b1e ("btrfs: lift some btrfs_cross_ref_exist checks in nocow path")
CC: stable@vger.kernel.org # 4.18+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:44 +01:00
Filipe Manana
41bd606769 Btrfs: fix fsync of files with multiple hard links in new directories
The log tree has a long standing problem that when a file is fsync'ed we
only check for new ancestors, created in the current transaction, by
following only the hard link for which the fsync was issued. We follow the
ancestors using the VFS' dget_parent() API. This means that if we create a
new link for a file in a directory that is new (or in an any other new
ancestor directory) and then fsync the file using an old hard link, we end
up not logging the new ancestor, and on log replay that new hard link and
ancestor do not exist. In some cases, involving renames, the file will not
exist at all.

Example:

  mkfs.btrfs -f /dev/sdb
  mount /dev/sdb /mnt

  mkdir /mnt/A
  touch /mnt/foo
  ln /mnt/foo /mnt/A/bar
  xfs_io -c fsync /mnt/foo

  <power failure>

In this example after log replay only the hard link named 'foo' exists
and directory A does not exist, which is unexpected. In other major linux
filesystems, such as ext4, xfs and f2fs for example, both hard links exist
and so does directory A after mounting again the filesystem.

Checking if any new ancestors are new and need to be logged was added in
2009 by commit 12fcfd22fe ("Btrfs: tree logging unlink/rename fixes"),
however only for the ancestors of the hard link (dentry) for which the
fsync was issued, instead of checking for all ancestors for all of the
inode's hard links.

So fix this by tracking the id of the last transaction where a hard link
was created for an inode and then on fsync fallback to a full transaction
commit when an inode has more than one hard link and at least one new hard
link was created in the current transaction. This is the simplest solution
since this is not a common use case (adding frequently hard links for
which there's an ancestor created in the current transaction and then
fsync the file). In case it ever becomes a common use case, a solution
that consists of iterating the fs/subvol btree for each hard link and
check if any ancestor is new, could be implemented.

This solves many unexpected scenarios reported by Jayashree Mohan and
Vijay Chidambaram, and for which there is a new test case for fstests
under review.

Fixes: 12fcfd22fe ("Btrfs: tree logging unlink/rename fixes")
CC: stable@vger.kernel.org # 4.4+
Reported-by: Vijay Chidambaram <vvijay03@gmail.com>
Reported-by: Jayashree Mohan <jayashree2912@gmail.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:43 +01:00
David Sterba
bbe339cc32 btrfs: drop extra enum initialization where using defaults
The first auto-assigned value to enum is 0, we can use that and not
initialize all members where the auto-increment does the same. This is
used for values that are not part of on-disk format.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:43 +01:00
David Sterba
5b840301ac btrfs: switch BTRFS_ORDERED_* to enums
We can use simple enum for values that are not part of on-disk format:
ordered extent flags.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:43 +01:00
David Sterba
50b5b6020f btrfs: switch EXTENT_FLAG_* to enums
We can use simple enum for values that are not part of on-disk format:
extent map flags.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:43 +01:00
David Sterba
80cb38362d btrfs: switch EXTENT_BUFFER_* to enums
We can use simple enum for values that are not part of on-disk format:
extent buffer flags;

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:43 +01:00
David Sterba
61fa90c16b btrfs: switch BTRFS_ROOT_* to enums
We can use simple enum for values that are not part of on-disk format:
root tree flags.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:42 +01:00
David Sterba
eb1a524c95 btrfs: switch BTRFS_FS_* to enums
We can use simple enum for values that are not part of on-disk format:
internal filesystem states.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:42 +01:00
David Sterba
688a75b9a3 btrfs: switch BTRFS_BLOCK_RSV_* to enums
We can use simple enum for values that are not part of on-disk format:
block reserve types.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:42 +01:00
David Sterba
b00146b5d5 btrfs: switch BTRFS_FS_STATE_* to enums
We can use simple enum for values that are not part of on-disk format:
global filesystem states.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:42 +01:00
Nikolay Borisov
da12fe5414 btrfs: Refactor btrfs_merge_bio_hook
This function really checks whether adding more data to the bio will
straddle a stripe/chunk. So first let's give it a more appropraite name
- btrfs_bio_fits_in_stripe. Secondly, the offset parameter was never
used to just remove it. Thirdly, pages are submitted to either btree or
data inodes so it's guaranteed that tree->ops is set so replace the
check with an ASSERT. Finally, document the parameters of the function.
No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:42 +01:00
Lu Fengqi
2ab4fd3135 btrfs: cleanup the useless DEFINE_WAIT in cleanup_transaction
When it was introduced in commit f094ac32ab ("Btrfs: fix NULL pointer
after aborting a transaction"), it was not used.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:42 +01:00
Johannes Thumshirn
d2e174d5d3 btrfs: document extent mapping assumptions in checksum
Document why map_private_extent_buffer() cannot return '1' (i.e. the map
spans two pages) for the csum_tree_block() case.

The current algorithm for detecting a page boundary crossing in
map_private_extent_buffer() will return a '1' *IFF* the extent buffer's
offset in the page + the offset passed in by csum_tree_block() and the
minimal length passed in by csum_tree_block() - 1 are bigger than
PAGE_SIZE.

We always pass BTRFS_CSUM_SIZE (32) as offset and a minimal length of 32
and the current extent buffer allocator always guarantees page aligned
extends, so the above condition can't be true.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:41 +01:00
Johannes Thumshirn
cc2c39d605 btrfs: don't initialize 'offset' in map_private_extent_buffer()
In map_private_extent_buffer() the 'offset' variable is initialized to a
page aligned version of the 'start' parameter.

But later on it is overwritten with either the offset from the extent
buffer's start or 0.

So get rid of the initial initialization.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:41 +01:00
Filipe Manana
a5fb114291 Btrfs: fix deadlock with memory reclaim during scrub
When a transaction commit starts, it attempts to pause scrub and it blocks
until the scrub is paused. So while the transaction is blocked waiting for
scrub to pause, we can not do memory allocation with GFP_KERNEL from scrub,
otherwise we risk getting into a deadlock with reclaim.

Checking for scrub pause requests is done early at the beginning of the
while loop of scrub_stripe() and later in the loop, scrub_extent() and
scrub_raid56_parity() are called, which in turn call scrub_pages() and
scrub_pages_for_parity() respectively. These last two functions do memory
allocations using GFP_KERNEL. Same problem could happen while scrubbing
the super blocks, since it calls scrub_pages().

We also can not have any of the worker tasks, created by the scrub task,
doing GFP_KERNEL allocations, because before pausing, the scrub task waits
for all the worker tasks to complete (also done at scrub_stripe()).

So make sure GFP_NOFS is used for the memory allocations because at any
time a scrub pause request can happen from another task that started to
commit a transaction.

Fixes: 58c4e17384 ("btrfs: scrub: use GFP_KERNEL on the submission path")
CC: stable@vger.kernel.org # 4.6+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:41 +01:00
Nikolay Borisov
78e62c02ab btrfs: Remove extent_io_ops::readpage_io_failed_hook
For data inodes this hook does nothing but to return -EAGAIN which is
used to signal to the endio routines that this bio belongs to a data
inode. If this is the case the actual retrying is handled by
bio_readpage_error. Alternatively, if this bio belongs to the btree
inode then btree_io_failed_hook just does some cleanup and doesn't retry
anything.

This patch simplifies the code flow by eliminating
readpage_io_failed_hook and instead open-coding btree_io_failed_hook in
end_bio_extent_readpage. Also eliminate some needless checks since IO is
always performed on either data inode or btree inode, both of which are
guaranteed to have their extent_io_tree::ops set.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:41 +01:00
Johannes Thumshirn
7b41ba71c1 btrfs: remove btrfs_bio_end_io_t
The btrfs_bio_end_io_t typedef was introduced with commit
a1d3c4786a ("btrfs: btrfs_multi_bio replaced with btrfs_bio")
but never used anywhere. This commit also introduced a forward declaration
of 'struct btrfs_bio' which is only needed for btrfs_bio_end_io_t.

Remove both as they're not needed anywhere.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:40 +01:00
David Sterba
b3a0dd50c3 btrfs: replace btrfs_io_bio::end_io with a simple helper
The end_io callback implemented as btrfs_io_bio_endio_readpage only
calls kfree. Also the callback is set only in case the csum buffer is
allocated and not pointing to the inline buffer. We can use that
information to drop the indirection and call a helper that will free the
csums only in the right case.

This shrinks struct btrfs_io_bio by 8 bytes.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:40 +01:00
David Sterba
31fecccbd7 btrfs: remove redundant csum buffer in btrfs_io_bio
The io_bio tracks checksums and has an inline buffer or an allocated
one. And there's a third member that points to the right one, but we
don't need to use an extra pointer for that. Let btrfs_io_bio::csum
point to the right buffer and check that the inline buffer is not
accidentally freed.

This shrinks struct btrfs_io_bio by 8 bytes.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:40 +01:00
David Sterba
600b6cf468 btrfs: replace async_cow::root with fs_info
The async_cow::root is used to propagate fs_info to async_cow_submit.
We can't use inode to reach it because it could become NULL after
write without compression in async_cow_start.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:40 +01:00
David Sterba
06ea01b1ee btrfs: merge btrfs_submit_bio_done to its caller
There's one caller and its code is simple, we can open code it in
run_one_async_done. The errors are passed through bio.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:40 +01:00
Anand Jain
7333bd02dc btrfs: balance: print to system log when balance ends or is paused
Print a kernel log message when the balance ends, either for cancel or
completed or if it is paused.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:39 +01:00
Anand Jain
56fc37d936 btrfs: balance: print args during start and resume
The information about balance arguments is important for system audit,
this patch prints the textual representation when balance starts or is
resumed.

Example command:

 $ btrfs balance start -f -mprofiles=raid1,convert=single,soft -dlimit=10..20,usage=50 /btrfs

Example kernel log output:

 BTRFS info (device sdb): balance: start -f -dusage=50,limit=10..20 -mconvert=single,soft,profiles=raid1 -sconvert=single,soft,profiles=raid1

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog, simplify code ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:39 +01:00
Anand Jain
f89e09cf45 btrfs: add helper to describe block group flags
Factor out helper that describes block group flags from
describe_relocation. The result will not be longer than the given size.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:39 +01:00
Filipe Manana
9a6f209e36 Btrfs: fix deadlock when enabling quotas due to concurrent snapshot creation
If the quota enable and snapshot creation ioctls are called concurrently
we can get into a deadlock where the task enabling quotas will deadlock
on the fs_info->qgroup_ioctl_lock mutex because it attempts to lock it
twice, or the task creating a snapshot tries to commit the transaction
while the task enabling quota waits for the former task to commit the
transaction while holding the mutex. The following time diagrams show how
both cases happen.

First scenario:

           CPU 0                                    CPU 1

 btrfs_ioctl()
  btrfs_ioctl_quota_ctl()
   btrfs_quota_enable()
    mutex_lock(fs_info->qgroup_ioctl_lock)
    btrfs_start_transaction()

                                             btrfs_ioctl()
                                              btrfs_ioctl_snap_create_v2
                                               create_snapshot()
                                                --> adds snapshot to the
                                                    list pending_snapshots
                                                    of the current
                                                    transaction

    btrfs_commit_transaction()
     create_pending_snapshots()
       create_pending_snapshot()
        qgroup_account_snapshot()
         btrfs_qgroup_inherit()
	   mutex_lock(fs_info->qgroup_ioctl_lock)
	    --> deadlock, mutex already locked
	        by this task at
		btrfs_quota_enable()

Second scenario:

           CPU 0                                    CPU 1

 btrfs_ioctl()
  btrfs_ioctl_quota_ctl()
   btrfs_quota_enable()
    mutex_lock(fs_info->qgroup_ioctl_lock)
    btrfs_start_transaction()

                                             btrfs_ioctl()
                                              btrfs_ioctl_snap_create_v2
                                               create_snapshot()
                                                --> adds snapshot to the
                                                    list pending_snapshots
                                                    of the current
                                                    transaction

                                                btrfs_commit_transaction()
                                                 --> waits for task at
                                                     CPU 0 to release
                                                     its transaction
                                                     handle

    btrfs_commit_transaction()
     --> sees another task started
         the transaction commit first
     --> releases its transaction
         handle
     --> waits for the transaction
         commit to be completed by
         the task at CPU 1

                                                 create_pending_snapshot()
                                                  qgroup_account_snapshot()
                                                   btrfs_qgroup_inherit()
                                                    mutex_lock(fs_info->qgroup_ioctl_lock)
                                                     --> deadlock, task at CPU 0
                                                         has the mutex locked but
                                                         it is waiting for us to
                                                         finish the transaction
                                                         commit

So fix this by setting the quota enabled flag in fs_info after committing
the transaction at btrfs_quota_enable(). This ends up serializing quota
enable and snapshot creation as if the snapshot creation happened just
before the quota enable request. The quota rescan task, scheduled after
committing the transaction in btrfs_quote_enable(), will do the accounting.

Fixes: 6426c7ad69 ("btrfs: qgroup: Fix qgroup accounting when creating snapshot")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:39 +01:00
Filipe Manana
5a8067c0d1 Btrfs: fix access to available allocation bits when starting balance
The available allocation bits members from struct btrfs_fs_info are
protected by a sequence lock, and when starting balance we access them
incorrectly in two different ways:

1) In the read sequence lock loop at btrfs_balance() we use the values we
   read from fs_info->avail_*_alloc_bits and we can immediately do actions
   that have side effects and can not be undone (printing a message and
   jumping to a label). This is wrong because a retry might be needed, so
   our actions must not have side effects and must be repeatable as long
   as read_seqretry() returns a non-zero value. In other words, we were
   essentially ignoring the sequence lock;

2) Right below the read sequence lock loop, we were reading the values
   from avail_metadata_alloc_bits and avail_data_alloc_bits without any
   protection from concurrent writers, that is, reading them outside of
   the read sequence lock critical section.

So fix this by making sure we only read the available allocation bits
while in a read sequence lock critical section and that what we do in the
critical section is repeatable (has nothing that can not be undone) so
that any eventual retry that is needed is handled properly.

Fixes: de98ced9e7 ("Btrfs: use seqlock to protect fs_info->avail_{data, metadata, system}_alloc_bits")
Fixes: 1450612797 ("btrfs: fix a bogus warning when converting only data or metadata")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:39 +01:00
Filipe Manana
0e6ec385b5 Btrfs: allow clear_extent_dirty() to receive a cached extent state record
We can have a lot freed extents during the life span of transaction, so
the red black tree that keeps track of the ranges of each freed extent
(fs_info->freed_extents[]) can get quite big. When finishing a
transaction commit we find each range, process it (discard the extents,
unpin them) and then remove it from the red black tree.

We can use an extent state record as a cache when searching for a range,
so that when we clean the range we can use the cached extent state we
passed to the search function instead of iterating the red black tree
again. Doing things as fast as possible when finishing a transaction (in
state TRANS_STATE_UNBLOCKED) is convenient as it reduces the time we
block another task that wants to commit the next transaction.

So change clear_extent_dirty() to allow an optional extent state record to
be passed as an argument, which will be passed down to __clear_extent_bit.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:38 +01:00
Nikolay Borisov
cc5de4e702 btrfs: Handle final split-brain possibility during fsid change
This patch lands the last case which needs to be handled by the fsid
change code. Namely, this is the case where a multidisk filesystem has
already undergone at least one successful fsid change i.e all disks
have the METADATA_UUID incompat bit and power failure occurs as another
fsid change is in progress. When such an event occurs, disks could be
split in 2 groups. One of the groups will have both METADATA_UUID and
CHANGING_FSID_V2 flags set coupled with old fsid/metadata_uuid pairs.
The other group of disks will have only METADATA_UUID bit set and their
fsid will be different than the one in disks in the first group. Here
we look at the following cases:

  a) A disk from the first group is scanned first, so fs_devices is
  created with stale fsid/metdata_uuid. Then when a disk from the
  second group is scanned it needs to first check whether there exists
  such an fs_devices that has fsid_change set to true (because it was
  created with a disk having the CHANGING_FSID_V2 flag), the
  metadata_uuid and fsid of the fs_devices will be different (since it was
  created by a disk which already has had at least 1 successful fsid change)
  and finally the metadata_uuid of the fs_devices will equal that of the
  currently scanned disk (because metadata_uuid never really changes).
  When the correct fs_devices is found the information from the scanned
  disk will replace the current one in fs_devices since the scanned disk
  will have higher generation number.

  b) A disk from the second group is scanned so fs_devices is created
  as usual with differing fsid/metdata_uid. Then when a disk from the
  first group is scanned the code detects that it has both
  CHANGING_FSID_V2 and METADATA_UUID flags set and will search for
  fs_devices that has differing metadata_uuid/fsid and whose
  metadata_uuid is the same as that of the scanned device.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:38 +01:00
Nikolay Borisov
7a62d0f073 btrfs: Handle one more split-brain scenario during fsid change
This commit continues hardening the scanning code to handle cases where
power loss could have caused disks in a multi-disk filesystem to be
in inconsistent state. Namely handle the situation that can occur when
some of the disks in multi-disk fs have completed their fsid change i.e
they have METADATA_UUID incompat flag set, have cleared the
CHANGING_FSID_V2 flag and their fsid/metadata_uuid are different. At
the same time the other half of the disks will have their
fsid/metadata_uuid unchanged and will only have CHANGING_FSID_V2 flag.

This is handled by introducing code in the scan path which:

 a) Handles the case when a device with CHANGING_FSID_V2 flag is
 scanned and as a result btrfs_fs_devices is created with matching
 fsid/metdata_uuid. Subsequently, when a device with completed fsid
 change is scanned it will detect this via the new code in find_fsid
 i.e that such an fs_devices exist that fsid_change flag is set to true,
 it's metadata_uuid/fsid match and the metadata_uuid of the scanned
 device matches that of the fs_devices. In this case, it's important to
 note that the devices which has its fsid change completed will have a
 higher generation number than the device with FSID_CHANGING_V2 flag
 set, so its superblock block will be used during mount. To prevent an
 assertion triggering because the sb used for mounting will have
 differing fsid/metadata_uuid than the ones in the fs_devices struct
 also add code in device_list_add which overwrites the values in
 fs_devices.

 b) Alternatively we can end up with a device that completed its
 fsid change be scanned first which will create the respective
 btrfs_fs_devices struct with differing fsid/metadata_uuid. In this
 case when a device with FSID_CHANGING_V2 flag set is scanned it will
 call the newly added find_fsid_inprogress function which will return
 the correct fs_devices.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:38 +01:00
Nikolay Borisov
d1a6300282 btrfs: add members to fs_devices to track fsid changes
In order to gracefully handle split-brain scenario during fsid change
(which are very unlikely, yet possible), two more pieces of information
will be necessary:

1. The highest generation number among all devices registered to a
   particular btrfs_fs_devices

2. A boolean flag whether a given btrfs_fs_devices was created by a
   device which had the FSID_CHANGING_V2 flag set.

This is a preparatory patch and just introduces the variables as well
as code which sets them, their actual use is going to happen in a later
patch.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:38 +01:00
Nikolay Borisov
fbc6feaec9 btrfs: Add handling for disk split-brain scenario during fsid change
Even though fsid change without rewrite is a very quick operation it's
still possible to experience a split-brain scenario if power loss occurs
at the most inconvenient time. This patch handles the case where power
failure occurs while the first transaction (the one setting
CHANGING_FSID_V2) flag is being persisted on disk. This can cause the
btrfs_fs_devices of this filesystem to be created by a device which:

 a) has the CHANGING_FSID_V2 flag set but its fsid value is intact

 b) or a device which doesn't have CHANGING_FSID_V2 flag set and its
    fsid value is intact

This situation is trivially handled by the current find_fsid code since
in both cases the devices are going to be treated like ordinary devices.
Since btrfs is always mounted using the superblock of the latest
device (the one with highest generation number), meaning it will have
the CHANGING_FSID_V2 flag set, ensure it's being cleared on mount. On
the first transaction commit following mount all disks will have it
cleared.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:38 +01:00
Nikolay Borisov
de37aa5131 btrfs: Remove fsid/metadata_fsid fields from btrfs_info
Currently btrfs_fs_info structure contains a copy of the
fsid/metadata_uuid fields. Same values are also contained in the
btrfs_fs_devices structure which fs_info has a reference to. Let's
reduce duplication by removing the fields from fs_info and always refer
to the ones in fs_devices. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:37 +01:00
Nikolay Borisov
56f20f4009 btrfs: Add sysfs support for metadata_uuid feature
Since the metadata_uuid is a new incompat feature it requires the
respective sysfs hooks. This patch adds the 'metdata_uuid' feature to
be shown if it supported by the kernel. Additionally it adds
/sys/fs/btrfs/UUID/metadata_uuid attribute which allows one to read
the current metadata_uuid.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:37 +01:00
Nikolay Borisov
7239ff4b2b btrfs: Introduce support for FSID change without metadata rewrite
This field is going to be used when the user wants to change the UUID
of the filesystem without having to rewrite all metadata blocks. This
field adds another level of indirection such that when the FSID is
changed what really happens is the current UUID (the one with which the
fs was created) is copied to the 'metadata_uuid' field in the superblock
as well as a new incompat flag is set METADATA_UUID. When the kernel
detects this flag is set it knows that the superblock in fact has 2
UUIDs:

1. Is the UUID which is user-visible, currently known as FSID.
2. Metadata UUID - this is the UUID which is stamped into all on-disk
   datastructures belonging to this file system.

When the new incompat flag is present device scanning checks whether
both fsid/metadata_uuid of the scanned device match any of the
registered filesystems. When the flag is not set then both UUIDs are
equal and only the FSID is retained on disk, metadata_uuid is set only
in-memory during mount.

Additionally a new metadata_uuid field is also added to the fs_info
struct. It's initialised either with the FSID in case METADATA_UUID
incompat flag is not set or with the metdata_uuid of the superblock
otherwise.

This commit introduces the new fields as well as the new incompat flag
and switches all users of the fsid to the new logic.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor updates in comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:37 +01:00
Johannes Thumshirn
ce9f967f31 btrfs: use EXPORT_FOR_TESTS for conditionally exported functions
Several functions in BTRFS are only used inside the source file they are
declared if CONFIG_BTRFS_FS_RUN_SANITY_TESTS is not defined. However if
CONFIG_BTRFS_FS_RUN_SANITY_TESTS is defined these functions are shared
with the unit tests code.

Before the introduction of the EXPORT_FOR_TESTS macro, these functions
could not be declared as static and the compiler had a harder task when
optimizing and inlining them.

As we have EXPORT_FOR_TESTS now, use it where appropriate to support the
compiler.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:37 +01:00
Johannes Thumshirn
f8f591df7d btrfs: introduce EXPORT_FOR_TESTS macro
Depending on whether CONFIG_BTRFS_FS_RUN_SANITY_TESTS is set, some BTRFS
functions are either local to the file they are implemented in and thus
should be declared static or are called from within the test
implementation defined in a different file.

Introduce an EXPORT_FOR_TESTS macro which depending on
CONFIG_BTRFS_FS_RUN_SANITY_TESTS either adds the 'static' keyword to a
function or not.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:37 +01:00
Johannes Thumshirn
e9a05cf31b btrfs: remove unused drop_on_err in btrfs_mkdir
Up to commit 32955c5422 ("btrfs: switch to discard_new_inode()") the
drop_on_err variable in btrfs_mkdir() was used to check whether the
inode had to be dropped via iput().

After commit 32955c5422 ("btrfs: switch to discard_new_inode()")
discard_new_inode() is called when err is set and inode is non NULL.
Therefore drop_on_err is not used anymore and thus causes a warning when
building with -Wunused-but-set-variable.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:36 +01:00
Nikolay Borisov
9bfd61d975 btrfs: Replace BUG_ON with ASSERT in find_lock_delalloc_range
lock_delalloc_pages should only return 2 values - 0 in case of success
and -EAGAIN if the range of pages to be locked should be shrunk due to
some of gone. Manual inspections confirms that this is indeed the case
since __process_pages_contig is where lock_delalloc_pages gets its
return value. The latter always returns 0  or -EAGAIN so the invariant
holds. No functional changes.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:36 +01:00
Nikolay Borisov
917aacecc5 btrfs: Sink find_lock_delalloc_range's 'max_bytes' argument
All callers of this function pass BTRFS_MAX_EXTENT_SIZE (128M) so let's
reduce the argument count and make that a local variable. No functional
changes.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:36 +01:00
Nikolay Borisov
64bc6c2a34 btrfs: Remove superfluous check form btrfs_remove_chunk
It's unnecessary to check map->stripes[i].dev for NULL given its value
is already set and dereferenced above the the check. No functional
changes.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:36 +01:00
Anand Jain
f9085abfae btrfs: don't report user-requested cancel as an error
As of now only user requested replace cancel can cancel the
replace-scrub so no need to log the error.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:36 +01:00
Anand Jain
49365e6976 btrfs: silence warning if replace is canceled
When we successfully cancel the device replace, its scrub worker returns
-ECANCELED, which is then passed to btrfs_dev_replace_finishing.

It cleans up based on the returned status and propagates the same
-ECANCELED back the parent function. As of now only user can cancel the
replace-scrub, so its ok to silence the warning here.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:35 +01:00
Anand Jain
53e62fb5a4 btrfs: dev-replace: add explicit check for replace result "no error"
We recast the replace return status
BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS to 0, to indicate no
error.
And since BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR should also return 0,
which is also declared as 0, so we just return. Instead add it to the if
statement so that there is enough clarity while reading the code.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:35 +01:00
Anand Jain
fe97e2e173 btrfs: dev-replace: replace's scrub must not be running in suspended state
When the replace state is in the suspended state, btrfs_scrub_cancel()
should fail with -ENOTCONN as there is no scrub running. As a safety
catch check if btrfs_scrub_cancel() returns -ENOTCONN and assert if it
doesn't.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:35 +01:00
Anand Jain
b47dda2ef6 btrfs: dev-replace: set result code of cancel by status of scrub
The device-replace needs to check the result code of the scrub workers
in btrfs_dev_replace_cancel and distinguish if successful cancel
operation and when the there was no operation running.

If btrfs_scrub_cancel() fails, return
BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED so that user can try
to cancel the replace again.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:35 +01:00
Anand Jain
d189dd70e2 btrfs: fix use-after-free due to race between replace start and cancel
The device replace cancel thread can race with the replace start thread
and if fs_info::scrubs_running is not yet set, btrfs_scrub_cancel() will
fail to stop the scrub thread.

The scrub thread continues with the scrub for replace which then will
try to write to the target device and which is already freed by the
cancel thread.

scrub_setup_ctx() warns as tgtdev is NULL.

  struct scrub_ctx *scrub_setup_ctx(struct btrfs_device *dev, int is_dev_replace)
  {
  ...
	  if (is_dev_replace) {
		  WARN_ON(!fs_info->dev_replace.tgtdev);  <===
		  sctx->pages_per_wr_bio = SCRUB_PAGES_PER_WR_BIO;
		  sctx->wr_tgtdev = fs_info->dev_replace.tgtdev;
		  sctx->flush_all_writes = false;
	  }

  [ 6724.497655] BTRFS info (device sdb): dev_replace from /dev/sdb (devid 1) to /dev/sdc started
  [ 6753.945017] BTRFS info (device sdb): dev_replace from /dev/sdb (devid 1) to /dev/sdc canceled
  [ 6852.426700] WARNING: CPU: 0 PID: 4494 at fs/btrfs/scrub.c:622 scrub_setup_ctx.isra.19+0x220/0x230 [btrfs]
  ...
  [ 6852.428928] RIP: 0010:scrub_setup_ctx.isra.19+0x220/0x230 [btrfs]
  ...
  [ 6852.432970] Call Trace:
  [ 6852.433202]  btrfs_scrub_dev+0x19b/0x5c0 [btrfs]
  [ 6852.433471]  btrfs_dev_replace_start+0x48c/0x6a0 [btrfs]
  [ 6852.433800]  btrfs_dev_replace_by_ioctl+0x3a/0x60 [btrfs]
  [ 6852.434097]  btrfs_ioctl+0x2476/0x2d20 [btrfs]
  [ 6852.434365]  ? do_sigaction+0x7d/0x1e0
  [ 6852.434623]  do_vfs_ioctl+0xa9/0x6c0
  [ 6852.434865]  ? syscall_trace_enter+0x1c8/0x310
  [ 6852.435124]  ? syscall_trace_enter+0x1c8/0x310
  [ 6852.435387]  ksys_ioctl+0x60/0x90
  [ 6852.435663]  __x64_sys_ioctl+0x16/0x20
  [ 6852.435907]  do_syscall_64+0x50/0x180
  [ 6852.436150]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Further, as the replace thread enters scrub_write_page_to_dev_replace()
without the target device it panics:

  static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
				      struct scrub_page *spage)
  {
  ...
	bio_set_dev(bio, sbio->dev->bdev); <======

  [ 6929.715145] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a0
  ..
  [ 6929.717106] Workqueue: btrfs-scrub btrfs_scrub_helper [btrfs]
  [ 6929.717420] RIP: 0010:scrub_write_page_to_dev_replace+0xb4/0x260
  [btrfs]
  ..
  [ 6929.721430] Call Trace:
  [ 6929.721663]  scrub_write_block_to_dev_replace+0x3f/0x60 [btrfs]
  [ 6929.721975]  scrub_bio_end_io_worker+0x1af/0x490 [btrfs]
  [ 6929.722277]  normal_work_helper+0xf0/0x4c0 [btrfs]
  [ 6929.722552]  process_one_work+0x1f4/0x520
  [ 6929.722805]  ? process_one_work+0x16e/0x520
  [ 6929.723063]  worker_thread+0x46/0x3d0
  [ 6929.723313]  kthread+0xf8/0x130
  [ 6929.723544]  ? process_one_work+0x520/0x520
  [ 6929.723800]  ? kthread_delayed_work_timer_fn+0x80/0x80
  [ 6929.724081]  ret_from_fork+0x3a/0x50

Fix this by letting the btrfs_dev_replace_finishing() to do the job of
cleaning after the cancel, including freeing of the target device.
btrfs_dev_replace_finishing() is called when btrfs_scub_dev() returns
along with the scrub return status.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:35 +01:00
Anand Jain
05c49e6bc1 btrfs: dev-replace: go back to suspend state if another EXCL_OP is running
In a secnario where balance and replace co-exists as below,

  - start balance
  - pause balance
  - start replace
  - reboot

and when system restarts, balance resumes first. Then the replace is
attempted to restart but will fail as the EXCL_OP lock is already held
by the balance. If so place the replace state back to
BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED state.

Fixes: 010a47bde9 ("btrfs: add proper safety check before resuming dev-replace")
CC: stable@vger.kernel.org # 4.18+
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:34 +01:00
Anand Jain
0d228ece59 btrfs: dev-replace: go back to suspended state if target device is missing
At the time of forced unmount we place the running replace to
BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED state, so when the system comes
back and expect the target device is missing.

Then let the replace state continue to be in
BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED state instead of
BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED as there isn't any matching scrub
running as part of replace.

Fixes: e93c89c1aa ("Btrfs: add new sources for device replace code")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:34 +01:00
Anand Jain
54862d6d28 btrfs: mark btrfs_dev_replace_start as static
There isn't any other consumer other than in its own file dev-replace.c.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:34 +01:00
Anand Jain
a9261d4125 btrfs: harden agaist duplicate fsid on scanned devices
It's not that impossible to imagine that a device OR a btrfs image is
copied just by using the dd or the cp command. Which in case both the
copies of the btrfs will have the same fsid. If on the system with
automount enabled, the copied FS gets scanned.

We have a known bug in btrfs, that we let the device path be changed
after the device has been mounted. So using this loop hole the new
copied device would appears as if its mounted immediately after it's
been copied.

For example:

Initially.. /dev/mmcblk0p4 is mounted as /

  $ lsblk
  NAME        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
  mmcblk0     179:0    0 29.2G  0 disk
  |-mmcblk0p4 179:4    0    4G  0 part /
  |-mmcblk0p2 179:2    0  500M  0 part /boot
  |-mmcblk0p3 179:3    0  256M  0 part [SWAP]
  `-mmcblk0p1 179:1    0  256M  0 part /boot/efi

  $ btrfs fi show
     Label: none  uuid: 07892354-ddaa-4443-90ea-f76a06accaba
     Total devices 1 FS bytes used 1.40GiB
     devid    1 size 4.00GiB used 3.00GiB path /dev/mmcblk0p4

Copy mmcblk0 to sda

  $ dd if=/dev/mmcblk0 of=/dev/sda

And immediately after the copy completes the change in the device
superblock is notified which the automount scans using btrfs device scan
and the new device sda becomes the mounted root device.

  $ lsblk
  NAME        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
  sda           8:0    1 14.9G  0 disk
  |-sda4        8:4    1    4G  0 part /
  |-sda2        8:2    1  500M  0 part
  |-sda3        8:3    1  256M  0 part
  `-sda1        8:1    1  256M  0 part
  mmcblk0     179:0    0 29.2G  0 disk
  |-mmcblk0p4 179:4    0    4G  0 part
  |-mmcblk0p2 179:2    0  500M  0 part /boot
  |-mmcblk0p3 179:3    0  256M  0 part [SWAP]
  `-mmcblk0p1 179:1    0  256M  0 part /boot/efi

  $ btrfs fi show /
    Label: none  uuid: 07892354-ddaa-4443-90ea-f76a06accaba
    Total devices 1 FS bytes used 1.40GiB
    devid    1 size 4.00GiB used 3.00GiB path /dev/sda4

The bug is quite nasty that you can't either unmount /dev/sda4 or
/dev/mmcblk0p4. And the problem does not get solved until you take sda
out of the system on to another system to change its fsid using the
'btrfstune -u' command.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:34 +01:00
Hans van Kranenburg
b50836edf9 btrfs: introduce nparity raid_attr
Instead of hardcoding exceptions for RAID5 and RAID6 in the code, use an
nparity field in raid_attr.

Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:34 +01:00
Hans van Kranenburg
da612e31ae btrfs: fix ncopies raid_attr for RAID56
RAID5 and RAID6 profile store one copy of the data, not 2 or 3. These
values are not yet used anywhere so there's no change.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:33 +01:00
Hans van Kranenburg
baf92114c7 btrfs: alloc_chunk: fix more DUP stripe size handling
Commit 92e222df7b "btrfs: alloc_chunk: fix DUP stripe size handling"
fixed calculating the stripe_size for a new DUP chunk.

However, the same calculation reappears a bit later, and that one was
not changed yet. The resulting bug that is exposed is that the newly
allocated device extents ('stripes') can have a few MiB overlap with the
next thing stored after them, which is another device extent or the end
of the disk.

The scenario in which this can happen is:
* The block device for the filesystem is less than 10GiB in size.
* The amount of contiguous free unallocated disk space chosen to use for
  chunk allocation is 20% of the total device size, or a few MiB more or
  less.

An example:
- The filesystem device is 7880MiB (max_chunk_size gets set to 788MiB)
- There's 1578MiB unallocated raw disk space left in one contiguous
  piece.

In this case stripe_size is first calculated as 789MiB, (half of
1578MiB).

Since 789MiB (stripe_size * data_stripes) > 788MiB (max_chunk_size), we
enter the if block. Now stripe_size value is immediately overwritten
while calculating an adjusted value based on max_chunk_size, which ends
up as 788MiB.

Next, the value is rounded up to a 16MiB boundary, 800MiB, which is
actually more than the value we had before. However, the last comparison
fails to detect this, because it's comparing the value with the total
amount of free space, which is about twice the size of stripe_size.

In the example above, this means that the resulting raw disk space being
allocated is 1600MiB, while only a gap of 1578MiB has been found. The
second device extent object for this DUP chunk will overlap for 22MiB
with whatever comes next.

The underlying problem here is that the stripe_size is reused all the
time for different things. So, when entering the code in the if block,
stripe_size is immediately overwritten with something else. If later we
decide we want to have the previous value back, then the logic to
compute it was copy pasted in again.

With this change, the value in stripe_size is not unnecessarily
destroyed, so the duplicated calculation is not needed any more.

Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:33 +01:00
Hans van Kranenburg
23f0ff1ec4 btrfs: alloc_chunk: improve chunk size variable name
The variable num_bytes is really a way too generic name for a variable
in this function. There are a dozen other variables that hold a number
of bytes as value.

Give it a name that actually describes what it does, which is holding
the size of the chunk that we're allocating.

Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:33 +01:00
Hans van Kranenburg
2f29df4fc2 btrfs: alloc_chunk: do not refurbish num_bytes
The variable num_bytes is used to store the chunk length of the chunk
that we're allocating. Do not reuse it for something really different in
the same function.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:33 +01:00
Ethan Lien
3cd24c6980 btrfs: use tagged writepage to mitigate livelock of snapshot
Snapshot is expected to be fast. But if there are writers steadily
creating dirty pages in our subvolume, the snapshot may take a very long
time to complete. To fix the problem, we use tagged writepage for
snapshot flusher as we do in the generic write_cache_pages(), so we can
omit pages dirtied after the snapshot command.

This does not change the semantics regarding which data get to the
snapshot, if there are pages being dirtied during the snapshotting
operation.  There's a sync called before snapshot is taken in old/new
case, any IO in flight just after that may be in the snapshot but this
depends on other system effects that might still sync the IO.

We do a simple snapshot speed test on a Intel D-1531 box:

fio --ioengine=libaio --iodepth=32 --bs=4k --rw=write --size=64G
--direct=0 --thread=1 --numjobs=1 --time_based --runtime=120
--filename=/mnt/sub/testfile --name=job1 --group_reporting & sleep 5;
time btrfs sub snap -r /mnt/sub /mnt/snap; killall fio

original: 1m58sec
patched:  6.54sec

This is the best case for this patch since for a sequential write case,
we omit nearly all pages dirtied after the snapshot command.

For a multi writers, random write test:

fio --ioengine=libaio --iodepth=32 --bs=4k --rw=randwrite --size=64G
--direct=0 --thread=1 --numjobs=4 --time_based --runtime=120
--filename=/mnt/sub/testfile --name=job1 --group_reporting & sleep 5;
time btrfs sub snap -r /mnt/sub /mnt/snap; killall fio

original: 15.83sec
patched:  10.35sec

The improvement is smaller compared to the sequential write case,
since we omit only half of the pages dirtied after snapshot command.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Ethan Lien <ethanlien@synology.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:33 +01:00
Nikolay Borisov
c629732d24 btrfs: Remove unused extent_state argument from btrfs_writepage_endio_finish_ordered
This parameter was never used, yet was part of the interface of the
function ever since its introduction as extent_io_ops::writepage_end_io_hook
in e6dcd2dc9c ("Btrfs: New data=ordered implementation"). Now that
NULL is passed everywhere as a value for this parameter let's remove it
for good. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:32 +01:00
Nikolay Borisov
8cc0237abc btrfs: Remove extent_page_data argument from writepage_delalloc
The only remaining use of the 'epd' argument in writepage_delalloc is
to reference the extent_io_tree which was set in extent_writepages. Since
it is guaranteed that page->mapping of any page passed to
writepage_delalloc (and __extent_writepage as the sole caller) to be
equal to that passed in extent_writepages we can directly get the
io_tree via the already passed inode (which is also taken from
page->mapping->host). No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:32 +01:00
Nikolay Borisov
7789a55aa1 btrfs: Move epd::extent_locked check to writepage_delalloc's caller
If epd::extent_locked is set then writepage_delalloc terminates. Make
this a bit more apparent in the caller by simply bubbling the check up.
This enables to remove epd as an argument to writepage_delalloc in a
future patch. No functional change.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:32 +01:00
Nikolay Borisov
fc8a168aa9 btrfs: Check for missing device before bio submission in btrfs_map_bio
Before btrfs_map_bio submits all stripe bios it does a number of checks
to ensure the device for every stripe is present. However, it doesn't do
a DEV_STATE_MISSING check, instead this is relegated to the lower level
btrfs_schedule_bio (in the async submission case, sync submission
doesn't check DEV_STATE_MISSING at all). Additionally
btrfs_schedule_bios does the duplicate device->bdev check which has
already been performed in btrfs_map_bio.

This patch moves the DEV_STATE_MISSING check in btrfs_map_bio and
removes the duplicate device->bdev check. Doing so ensures that no bio
cloning/submission happens for both async/sync requests in the face of
missing device. This makes the async io submission path slightly shorter
in terms of instruction count. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:32 +01:00
Anand Jain
ab457246f8 btrfs: remove redundant replace_state init
dev_replace::replace_state has been set to
BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED (0) in the same function,
So delete the line which sets replace_state = 0;

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:32 +01:00
Filipe Manana
6d4cbf7903 Btrfs: remove no longer used io_err from btrfs_log_ctx
The io_err field of struct btrfs_log_ctx is no longer used after the
recent simplification of the fast fsync path, where we now wait for
ordered extents to complete before logging the inode. We did this in
commit b5e6c3e170 ("btrfs: always wait on ordered extents at fsync
time") and commit a2120a473a ("btrfs: clean up the left over
logged_list usage") removed its last use.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:31 +01:00
Filipe Manana
59b0713a8a Btrfs: simpler and more efficient cleanup of a log tree's extent io tree
We currently are in a loop finding each range (corresponding to a btree
node/leaf) in a log root's extent io tree and then clean it up. This is a
waste of time since we are traversing the extent io tree's rb_tree more
times then needed (one for a range lookup and another for cleaning it up)
without any good reason.

We free the log trees when we are in the critical section of a transaction
commit (the transaction state is set to TRANS_STATE_COMMIT_DOING), so it's
of great convenience to do everything as fast as possible in order to
reduce the time we block other tasks from starting a new transaction.

So fix this by traversing the extent io tree once and cleaning up all its
records in one go while traversing it.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:31 +01:00
Nikolay Borisov
46cc775e29 btrfs: Adjust loop in free_extent_buffer
The loop construct in free_extent_buffer was added in
242e18c7c1 ("Btrfs: reduce lock contention on extent buffer locks")
as means of reducing the times the eb lock is taken, the non-last ref
count is decremented and lock is released. As the special handling
of UNMAPPED extent buffers was removed now there is only one decrement
op which is happening for EXTENT_BUFFER_UNMAPPED case.

This commit modifies the loop condition so that in case of UNMAPPED
buffers the eb's lock is taken only if we are 100% sure the eb is going
to be freed by the current executor of the code. Additionally, remove
superfluous ref count ops in btrfs test.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:31 +01:00
Nikolay Borisov
9cfc8ba712 btrfs: Remove special handling of EXTENT_BUFFER_UNMAPPED while freeing
Now that the whole of btrfs code has been audited for eb reference count
management it's time to remove the hunk in free_extent_buffer that
essentially considered the condition

  "eb->ref == 2 && EXTENT_BUFFER_DUMMY"

to equal "eb->ref = 1". Also remove the last location
which takes an extra reference count in alloc_test_extent_buffer.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:31 +01:00
Nikolay Borisov
df44971468 btrfs: Remove unnecessary tree locking code in qgroup_rescan_leaf
In qgroup_rescan_leaf a copy is made of the target leaf by calling
btrfs_clone_extent_buffer. The latter allocates a new buffer and
attaches a new set of pages and copies the content of the source buffer.
The new scratch buffer is only used to iterate it's items, it's not
published anywhere and cannot be accessed by a third party.

Hence, it's not necessary to perform any locking on it whatsoever.
Furthermore, remove the extra extent_buffer_get call since the new
buffer is always allocated with a reference count of 1 which is
sufficient here.  No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:31 +01:00
Nikolay Borisov
8c7eeb6557 btrfs: Remove extra reference count bumps in btrfs_compare_trees
When the 2 comparison trees roots are initialised they are private to
the function and already have reference counts of 1 each. There is no
need to further increment the reference count since the cloned buffers
are already accessed via struct btrfs_path. Eventually the 2 paths used
for comparison are going to be released, effectively disposing of the
cloned buffers.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:30 +01:00
Nikolay Borisov
24cee18a1c btrfs: Remove extraneous extent_buffer_get from tree_mod_log_rewind
When a rewound buffer is created it already has a ref count of 1 and the
dummy flag set. Then another ref is taken bumping the count to 2.
Finally when this buffer is released from btrfs_release_path the extra
reference is decremented by the special handling code in
free_extent_buffer.

However, this special code is in fact redundant sinca ref count of 1 is
still correct since the buffer is only accessed via btrfs_path struct.
This paves the way forward of removing the special handling in
free_extent_buffer.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:30 +01:00
Nikolay Borisov
6c122e2a0c btrfs: Remove redundant extent_buffer_get in get_old_root
get_old_root used used only by btrfs_search_old_slot to initialise the
path structure. The old root is always a cloned buffer (either via alloc
dummy or via btrfs_clone_extent_buffer) and its reference count is 2: 1
from allocation, 1 from extent_buffer_get call in get_old_root.

This latter explicit ref count acquire operation is in fact unnecessary
since the semantic is such that the newly allocated buffer is handed
over to the btrfs_path for lifetime management. Considering this just
remove the extra extent_buffer_get in get_old_root.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:30 +01:00
Nikolay Borisov
5c623d334a btrfs: Remove needless tree locking in iterate_inode_extrefs
In iterate_inode_exrefs the eb is cloned via btrfs_clone_extent_buffer
which creates a private extent buffer with the dummy flag set and ref
count of 1. Then this buffer is locked for reading and its ref count is
incremented by 1. Finally it's fed to the passed iterate_irefs_t
function. The actual iterate call back is inode_to_path (coming from
paths_from_inode) which feeds the eb to btrfs_ref_to_path. In this final
function the passed eb is only read by first assigning it to the local
eb variable. This variable is only modified in the case another eb was
referenced from the passed path that is eb != eb_in check triggers.

Considering this there is no point in locking the cloned eb in
iterate_inode_refs since it's never being modified and is not published
anywhere. Furthermore the cloned eb is completely fine having its ref
count be 1.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:30 +01:00
Nikolay Borisov
e5bba0b0f8 btrfs: Remove needless tree locking in iterate_inode_refs
In iterate_inode_refs the eb is cloned via btrfs_clone_extent_buffer
which creates a private extent buffer with the dummy flag set and ref
count of 1. Then this buffer is locked for reading and its ref count is
incremented by 1. Finally it's fed to the passed iterate_irefs_t
function. The actual iterate call back is inode_to_path (coming from
paths_from_inode) which feeds the eb to btrfs_ref_to_path. In this final
function the passed eb is only read by first assigning it to the local
eb variable. This variable is only modified in the case another eb was
referenced from the passed path that is eb != eb_in check triggers.

Considering this there is no point in locking the cloned eb in
iterate_inode_refs since it's never being modified and is not published
anywhere. Furthermore the cloned eb is completely fine having its ref
count be 1.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:30 +01:00
Qu Wenruo
d9cb2459b2 btrfs: tests: Use BTRFS_MAX_EXTENT_SIZE to replace the intermediate number
In extent-io self test, we need 2 ordered extents at its maximum size to
do the test.

Instead of using the intermediate numbers, use BTRFS_MAX_EXTENT_SIZE for
@max_bytes, and twice @max_bytes for @total_dirty.  This should explain
why we need all these magic numbers and prevent people to modify them by
accident.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:30 +01:00
Omar Sandoval
ed46ff3d42 Btrfs: support swap files
Btrfs has not allowed swap files since commit 35054394c4 ("Btrfs: stop
providing a bmap operation to avoid swapfile corruptions"). However, now
that the proper restrictions are in place, Btrfs can support swap files
through the swap file a_ops, similar to iomap in commit 67482129cd
("iomap: add a swapfile activation function").

For Btrfs, activation needs to make sure that the file can be used as a
swap file, which currently means that it must be fully allocated as
NOCOW with no compression on one device. It must also do the proper
tracking so that ioctls will not interfere with the swap file.
Deactivation clears this tracking.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:29 +01:00
Omar Sandoval
60ca842e34 Btrfs: rename and export get_chunk_map
The Btrfs swap code is going to need it, so give it a btrfs_ prefix and
make it non-static.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:29 +01:00
Omar Sandoval
eede2bf34f Btrfs: prevent ioctls from interfering with a swap file
A later patch will implement swap file support for Btrfs, but before we
do that, we need to make sure that the various Btrfs ioctls cannot
change a swap file.

When a swap file is active, we must make sure that the extents of the
file are not moved and that they don't become shared. That means that
the following are not safe:

- chattr +c (enable compression)
- reflink
- dedupe
- snapshot
- defrag

Don't allow those to happen on an active swap file.

Additionally, balance, resize, device remove, and device replace are
also unsafe if they affect an active swapfile. Add a red-black tree of
block groups and devices which contain an active swapfile. Relocation
checks each block group against this tree and skips it or errors out for
balance or resize, respectively. Device remove and device replace check
the tree for the device they will operate on.

Note that we don't have to worry about chattr -C (disable nocow), which
we ignore for non-empty files, because an active swapfile must be
non-empty and can't be truncated. We also don't have to worry about
autodefrag because it's only done on COW files. Truncate and fallocate
are already taken care of by the generic code. Device add doesn't do
relocation so it's not an issue, either.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:29 +01:00
Nikolay Borisov
abbb55f4cd btrfs: Remove extent_io_ops::split_extent_hook callback
This is the counterpart to merge_extent_hook, similarly, it's used only
for data/freespace inodes so let's remove it, rename it and call it
directly where necessary. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:29 +01:00
Nikolay Borisov
5c848198aa btrfs: Remove extent_io_ops::merge_extent_hook callback
This callback is used only for data and free space inodes. Such inodes
are guaranteed to have their extent_io_tree::private_data set to the
inode struct. Exploit this fact to directly call the function. Also give
it a more descriptive name. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:28 +01:00
Nikolay Borisov
a36bb5f9a9 btrfs: Remove extent_io_ops::clear_bit_hook callback
This is the counterpart to ex-set_bit_hook (now btrfs_set_delalloc_extent),
similar to what was done before remove clear_bit_hook and rename the
function. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:28 +01:00
Nikolay Borisov
e06a1fc99c btrfs: Remove extent_io_ops::set_bit_hook extent_io callback
This callback is used to properly account delalloc extents for data
inodes (ordinary file inodes and freespace v1 inodes). Those can be
easily identified since they have their extent_io trees ->private_data
member point to the inode. Let's exploit this fact to remove the
needless indirection through extent_io_hooks and directly call the
function. Also give the function a name which reflects its purpose -
btrfs_set_delalloc_extent.

This patch also modified test_find_delalloc so that the extent_io_tree
used for testing doesn't have its ->private_data set which would have
caused a crash in btrfs_set_delalloc_extent due to the btrfs_inode->root
member not being initialised. The old version of the code also didn't
call set_bit_hook since the extent_io ops weren't set for the inode.  No
functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:28 +01:00
Nikolay Borisov
65a680f6b7 btrfs: Remove extent_io_ops::check_extent_io_range callback
This callback was only used in debug builds by btrfs_leak_debug_check.
A better approach is to move its implementation in
btrfs_leak_debug_check and ensure the latter is only executed for extent
tree which have ->private_data set i.e. relate to a data node and not
the btree one. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:28 +01:00
Nikolay Borisov
7087a9d8db btrfs: Remove extent_io_ops::writepage_end_io_hook
This callback is ony ever called for data page writeout so there is no
need to actually abstract it via extent_io_ops. Lets just export it,
remove the definition of the callback and call it directly in the
functions that invoke the callback. Also rename the function to
btrfs_writepage_endio_finish_ordered since what it really does is
account finished io in the ordered extent data structures.  No
functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:28 +01:00
Nikolay Borisov
d75855b451 btrfs: Remove extent_io_ops::writepage_start_hook
This hook is called only from __extent_writepage_io which is already
called only from the data page writeout path. So there is no need to
make an indirect call via extent_io_ops. This patch just removes the
callback definition, exports the callback function and calls it directly
at the only call site. Also give the function a more descriptive name.
No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Nikolay Borisov
5eaad97af8 btrfs: Remove extent_io_ops::fill_delalloc
This callback is called only from writepage_delalloc which in turn is
guaranteed to be called from the data page writeout path. In the end
there is no reason to have the call to this function to be indrected via
the extent_io_ops structure. This patch removes the callback definition,
exports the function and calls it directly. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ rename to btrfs_run_delalloc_range ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Nikolay Borisov
06f2548f9d btrfs: Add function to distinguish between data and btree inode
This will be used in future patches that remove the optional
extent_io_ops callbacks.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Qu Wenruo
05a37c4860 btrfs: volumes: Make sure no dev extent is beyond device boundary
Add extra dev extent end check against device boundary.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Qu Wenruo
5eb193812a btrfs: volumes: Make sure there is no overlap of dev extents at mount time
Enhance btrfs_verify_dev_extents() to remember previous checked dev
extents, so it can verify no dev extents can overlap.

Analysis from Hans:

"Imagine allocating a DATA|DUP chunk.

 In the chunk allocator, we first set...
   max_stripe_size = SZ_1G;
   max_chunk_size = BTRFS_MAX_DATA_CHUNK_SIZE
 ... which is 10GiB.

 Then...
   /* we don't want a chunk larger than 10% of writeable space */
   max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
       		 max_chunk_size);

 Imagine we only have one 7880MiB block device in this filesystem. Now
 max_chunk_size is down to 788MiB.

 The next step in the code is to search for max_stripe_size * dev_stripes
 amount of free space on the device, which is in our example 1GiB * 2 =
 2GiB. Imagine the device has exactly 1578MiB free in one contiguous
 piece. This amount of bytes will be put in devices_info[ndevs - 1].max_avail

 Next we recalculate the stripe_size (which is actually the device extent
 length), based on the actual maximum amount of available raw disk space:
   stripe_size = div_u64(devices_info[ndevs - 1].max_avail, dev_stripes);

 stripe_size is now 789MiB

 Next we do...
   data_stripes = num_stripes / ncopies
 ...where data_stripes ends up as 1, because num_stripes is 2 (the amount
 of device extents we're going to have), and DUP has ncopies 2.

 Next there's a check...
   if (stripe_size * data_stripes > max_chunk_size)
 ...which matches because 789MiB * 1 > 788MiB.

 We go into the if code, and next is...
   stripe_size = div_u64(max_chunk_size, data_stripes);
 ...which resets stripe_size to max_chunk_size: 788MiB

 Next is a fun one...
   /* bump the answer up to a 16MB boundary */
   stripe_size = round_up(stripe_size, SZ_16M);
 ...which changes stripe_size from 788MiB to 800MiB.

 We're not done changing stripe_size yet...
   /* But don't go higher than the limits we found while searching
    * for free extents
    */
   stripe_size = min(devices_info[ndevs - 1].max_avail,
       	      stripe_size);

 This is bad. max_avail is twice the stripe_size (we need to fit 2 device
 extents on the same device for DUP).

 The result here is that 800MiB < 1578MiB, so it's unchanged. However,
 the resulting DUP chunk will need 1600MiB disk space, which isn't there,
 and the second dev_extent might extend into the next thing (next
 dev_extent? end of device?) for 22MiB.

 The last shown line of code relies on a situation where there's twice
 the value of stripe_size present as value for the variable stripe_size
 when it's DUP. This was actually the case before commit 92e222df7b
 "btrfs: alloc_chunk: fix DUP stripe size handling", from which I quote:
   "[...] in the meantime there's a check to see if the stripe_size does
 not exceed max_chunk_size. Since during this check stripe_size is twice
 the amount as intended, the check will reduce the stripe_size to
 max_chunk_size if the actual correct to be used stripe_size is more than
 half the amount of max_chunk_size."

 In the previous version of the code, the 16MiB alignment (why is this
 done, by the way?) would result in a 50% chance that it would actually
 do an 8MiB alignment for the individual dev_extents, since it was
 operating on double the size. Does this matter?

 Does it matter that stripe_size can be set to anything which is not
 16MiB aligned because of the amount of remaining available disk space
 which is just taken?

 What is the main purpose of this round_up?

 The most straightforward thing to do seems something like...
   stripe_size = min(
       div_u64(devices_info[ndevs - 1].max_avail, dev_stripes),
       stripe_size
   )
 ..just putting half of the max_avail into stripe_size."

Link: https://lore.kernel.org/linux-btrfs/b3461a38-e5f8-f41d-c67c-2efac8129054@mendix.com/
Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
[ add analysis from report ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Qu Wenruo
e72d79d6bc btrfs: Refactor find_free_extent loops update into find_free_extent_update_loop
We have a complex loop design for find_free_extent(), that has different
behavior for each loop, some even includes new chunk allocation.

Instead of putting such a long code into find_free_extent() and makes it
harder to read, just extract them into find_free_extent_update_loop().

With all the cleanups, the main find_free_extent() should be pretty
barebone:

find_free_extent()
|- Iterate through all block groups
|  |- Get a valid block group
|  |- Try to do clustered allocation in that block group
|  |- Try to do unclustered allocation in that block group
|  |- Check if the result is valid
|  |  |- If valid, then exit
|  |- Jump to next block group
|
|- Push harder to find free extents
   |- If not found, re-iterate all block groups

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
[ copy callchain from changelog to function comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Qu Wenruo
e1a4184815 btrfs: Refactor unclustered extent allocation into find_free_extent_unclustered()
This patch will extract unclsutered extent allocation code into
find_free_extent_unclustered().

And this helper function will use return value to indicate what to do
next.

This should make find_free_extent() a little easier to read.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
[Update merge conflict with fb5c39d7a8 ("btrfs: don't use ctl->free_space for max_extent_size")]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Qu Wenruo
d06e3bb690 btrfs: Refactor clustered extent allocation into find_free_extent_clustered
We have two main methods to find free extents inside a block group:

1) clustered allocation
2) unclustered allocation

This patch will extract the clustered allocation into
find_free_extent_clustered() to make it a little easier to read.

Instead of jumping between different labels in find_free_extent(), the
helper function will use return value to indicate different behavior.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Qu Wenruo
b4bd745d12 btrfs: Introduce find_free_extent_ctl structure for later rework
Instead of tons of different local variables in find_free_extent(),
extract them into find_free_extent_ctl structure, and add better
explanation for them.

Some modification may looks redundant, but will later greatly simplify
function parameter list during find_free_extent() refactor.

Also add two comments to co-operate with fb5c39d7a8 ("btrfs: don't use
ctl->free_space for max_extent_size"), to make ffe_ctl->max_extent_size
update more reader-friendly.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Lu Fengqi
e2907c1a6a btrfs: extent-tree: Detect bytes_pinned underflow earlier
Introduce a new wrapper update_bytes_pinned to replace open coded
bytes_pinned modifiers. Now the underflows of space_info::bytes_pinned
get detected and reported.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Qu Wenruo
9f9b8e8d0e btrfs: extent-tree: Detect bytes_may_use underflow earlier
Although we have space_info::bytes_may_use underflow detection in
btrfs_free_reserved_data_space_noquota(), we have more callers who are
subtracting number from space_info::bytes_may_use.

So instead of doing underflow detection for every caller, introduce a
new wrapper update_bytes_may_use() to replace open coded bytes_may_use
modifiers.

This also introduce a macro to declare more wrappers, but currently
space_info::bytes_may_use is the mostly interesting one.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:25 +01:00
Filipe Manana
85dd506c8e Btrfs: remove no longer used stuff for tracking pending ordered extents
Tracking pending ordered extents per transaction was introduced in commit
50d9aa99bd ("Btrfs: make sure logged extents complete in the current
transaction V3") and later updated in commit 161c3549b4 ("Btrfs: change
how we wait for pending ordered extents").

However now that on fsync we always wait for ordered extents to complete
before logging, done in commit 5636cf7d6d ("btrfs: remove the logged
extents infrastructure"), we no longer need the stuff to track for pending
ordered extents, which was not completely removed in the mentioned commit.
So remove the remaining of the pending ordered extents infrastructure.

Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:25 +01:00
Filipe Manana
ce02f03266 Btrfs: remove no longer used logged range variables when logging extents
The logged_start and logged_end variables, at btrfs_log_changed_extents,
were added in commit 8c6c592831 ("btrfs: log csums for all modified
extents"). However since the recent simplification for fsync, which makes
us wait for all ordered extents to complete before logging extents, we
no longer need those variables. Commit a2120a473a ("btrfs: clean up the
left over logged_list usage") forgot to remove them.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:25 +01:00
Nikolay Borisov
052b8cfa40 locks: Use inode_is_open_for_write
Use the aptly named function rather than open coding it. No functional
changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-12-17 07:19:46 -05:00
Linus Torvalds
6531e115b7 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "11 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  scripts/spdxcheck.py: always open files in binary mode
  checkstack.pl: fix for aarch64
  userfaultfd: check VM_MAYWRITE was set after verifying the uffd is registered
  fs/iomap.c: get/put the page in iomap_page_create/release()
  hugetlbfs: call VM_BUG_ON_PAGE earlier in free_huge_page()
  memblock: annotate memblock_is_reserved() with __init_memblock
  psi: fix reference to kernel commandline enable
  arch/sh/include/asm/io.h: provide prototypes for PCI I/O mapping in asm/io.h
  mm/sparse: add common helper to mark all memblocks present
  mm: introduce common STRUCT_PAGE_MAX_SHIFT define
  alpha: fix hang caused by the bootmem removal
2018-12-14 15:35:30 -08:00
Andrea Arcangeli
01e881f5a1 userfaultfd: check VM_MAYWRITE was set after verifying the uffd is registered
Calling UFFDIO_UNREGISTER on virtual ranges not yet registered in uffd
could trigger an harmless false positive WARN_ON.  Check the vma is
already registered before checking VM_MAYWRITE to shut off the false
positive warning.

Link: http://lkml.kernel.org/r/20181206212028.18726-2-aarcange@redhat.com
Cc: <stable@vger.kernel.org>
Fixes: 29ec90660d ("userfaultfd: shmem/hugetlbfs: only allow to register VM_MAYWRITE vmas")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: syzbot+06c7092e7d71218a2c16@syzkaller.appspotmail.com
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-14 15:05:45 -08:00
Piotr Jaroszynski
61c6de6672 fs/iomap.c: get/put the page in iomap_page_create/release()
migrate_page_move_mapping() expects pages with private data set to have
a page_count elevated by 1.  This is what used to happen for xfs through
the buffer_heads code before the switch to iomap in commit 82cb14175e
("xfs: add support for sub-pagesize writeback without buffer_heads").
Not having the count elevated causes move_pages() to fail on memory
mapped files coming from xfs.

Make iomap compatible with the migrate_page_move_mapping() assumption by
elevating the page count as part of iomap_page_create() and lowering it
in iomap_page_release().

It causes the move_pages() syscall to misbehave on memory mapped files
from xfs.  It does not not move any pages, which I suppose is "just" a
perf issue, but it also ends up returning a positive number which is out
of spec for the syscall.  Talking to Michal Hocko, it sounds like
returning positive numbers might be a necessary update to move_pages()
anyway though
(https://lkml.kernel.org/r/20181116114955.GJ14706@dhcp22.suse.cz).

I only hit this in tests that verify that move_pages() actually moved
the pages.  The test also got confused by the positive return from
move_pages() (it got treated as a success as positive numbers were not
expected and not handled) making it a bit harder to track down what's
going on.

Link: http://lkml.kernel.org/r/20181115184140.1388751-1-pjaroszynski@nvidia.com
Fixes: 82cb14175e ("xfs: add support for sub-pagesize writeback without buffer_heads")
Signed-off-by: Piotr Jaroszynski <pjaroszynski@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Brian Foster <bfoster@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-14 15:05:45 -08:00
Linus Torvalds
380ef2c9ad for-linus-20181214
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Merge tag 'for-linus-20181214' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Three small fixes for this week. contains:

   - spectre indexing fix for aio (Jeff)

   - fix for the previous zeroing bio fix, we don't need it for user
     mapped pages, and in fact it breaks some applications if we do
     (Keith)

   - allocation failure fix for null_blk with zoned (Shin'ichiro)"

* tag 'for-linus-20181214' of git://git.kernel.dk/linux-block:
  block: Fix null_blk_zoned creation failure with small number of zones
  aio: fix spectre gadget in lookup_ioctx
  block/bio: Do not zero user pages
2018-12-14 12:18:30 -08:00
Benjamin Coddington
b8eee0e90f lockd: Show pid of lockd for remote locks
Commit 9d5b86ac13 ("fs/locks: Remove fl_nspid and use fs-specific l_pid
for remote locks") specified that the l_pid returned for F_GETLK on a local
file that has a remote lock should be the pid of the lock manager process.
That commit, while updating other filesystems, failed to update lockd, such
that locks created by lockd had their fl_pid set to that of the remote
process holding the lock.  Fix that here to be the pid of lockd.

Also, fix the client case so that the returned lock pid is negative, which
indicates a remote lock on a remote file.

Fixes: 9d5b86ac13 ("fs/locks: Remove fl_nspid and use fs-specific...")
Cc: stable@vger.kernel.org

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-12-14 12:52:16 -05:00
Olga Kornievskaia
03b31f4896 NFSD remove OP_CACHEME from 4.2 op_flags
OP_CACHEME is only for the 4.0 operations.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-12-14 12:52:15 -05:00
Linus Torvalds
c19bf74fe4 Luis discovered a problem with the new copyfrom offload on the server
side.  Disable it for now.
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Merge tag 'ceph-for-4.20-rc7' of https://github.com/ceph/ceph-client

Pull ceph fix from Ilya Dryomov:
 "Luis discovered a problem with the new copyfrom offload on the server
  side. Disable it for now"

* tag 'ceph-for-4.20-rc7' of https://github.com/ceph/ceph-client:
  ceph: make 'nocopyfrom' a default mount option
2018-12-14 09:22:14 -08:00
Chao Yu
8d64d365ae f2fs: fix to reorder set_page_dirty and wait_on_page_writeback
This patch reorders flow from

- update page
- set_page_dirty
- wait_on_page_writeback

to

- wait_on_page_writeback
- update page
- set_page_dirty

The reason is:
- set_page_dirty will increase reference of dirty page, the reference
should be cleared before wait_on_page_writeback to keep its consistency.
- some devices need stable page during page writebacking, so we
should not change page's data.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-12-14 06:38:36 -08:00
Sheng Yong
2062e0c3da f2fs: clear PG_writeback if IPU failed
If IPU failed, nothing is commited, we should end page writeback.

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-12-14 06:38:12 -08:00
Jaegeuk Kim
0cd6d9b0d2 f2fs: add an ioctl() to explicitly trigger fsck later
This adds an option in ioctl(F2FS_IOC_SHUTDOWN) in order to trigger fsck by
setting a NEED_FSCK flag.

Generally, shutdown is used for the test to validate filesystem consistency, and
setting NEED_FSCK flag can be used for Android to trigger fsck.f2fs at boot time
explicitly so that we could measure the elapsed time as well as force filesystem
check.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-12-14 06:38:02 -08:00
Ivan Delalande
ea5751ccd6 proc/sysctl: don't return ENOMEM on lookup when a table is unregistering
proc_sys_lookup can fail with ENOMEM instead of ENOENT when the
corresponding sysctl table is being unregistered. In our case we see
this upon opening /proc/sys/net/*/conf files while network interfaces
are being deleted, which confuses our configuration daemon.

The problem was successfully reproduced and this fix tested on v4.9.122
and v4.20-rc6.

v2: return ERR_PTRs in all cases when proc_sys_make_inode fails instead
of mixing them with NULL. Thanks Al Viro for the feedback.

Fixes: ace0c791e6 ("proc/sysctl: Don't grab i_lock under sysctl_lock.")
Cc: stable@vger.kernel.org
Signed-off-by: Ivan Delalande <colona@arista.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-12-13 20:59:44 -05:00
Richard Weinberger
e58725d51f ubifs: Handle re-linking of inodes correctly while recovery
UBIFS's recovery code strictly assumes that a deleted inode will never
come back, therefore it removes all data which belongs to that inode
as soon it faces an inode with link count 0 in the replay list.
Before O_TMPFILE this assumption was perfectly fine. With O_TMPFILE
it can lead to data loss upon a power-cut.

Consider a journal with entries like:
0: inode X (nlink = 0) /* O_TMPFILE was created */
1: data for inode X /* Someone writes to the temp file */
2: inode X (nlink = 0) /* inode was changed, xattr, chmod, … */
3: inode X (nlink = 1) /* inode was re-linked via linkat() */

Upon replay of entry #2 UBIFS will drop all data that belongs to inode X,
this will lead to an empty file after mounting.

As solution for this problem, scan the replay list for a re-link entry
before dropping data.

Fixes: 474b93704f ("ubifs: Implement O_TMPFILE")
Cc: stable@vger.kernel.org
Cc: Russell Senior <russell@personaltelco.net>
Cc: Rafał Miłecki <zajec5@gmail.com>
Reported-by: Russell Senior <russell@personaltelco.net>
Reported-by: Rafał Miłecki <zajec5@gmail.com>
Tested-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-12-13 22:18:24 +01:00
Gabor Juhos
d62e98ed1e ubifs: Fix default compression selection in ubifs
When ubifs is build without the LZO compressor and no compressor is
given the creation of the default file system will fail. before
selection the LZO compressor check if it is present and if not fall back
to the zlib or none.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-12-13 22:09:19 +01:00
Garry McNulty
6554a56f35 ubifs: Fix memory leak on error condition
If the call to ubifs_read_nnode() fails in ubifs_lpt_calc_hash() an
error is returned without freeing the memory allocated to 'buf'.
Read and check the root node before allocating the buffer.

Detected by CoverityScan, CID 1441025 ("Resource leak")

Signed-off-by: Garry McNulty <garrmcnu@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-12-13 22:09:13 +01:00
Arnd Bergmann
60eb5da243 ubifs: auth: Add CONFIG_KEYS dependency
The new authentication support causes a build failure
when CONFIG_KEYS is disabled, so add a dependency.

fs/ubifs/auth.c: In function 'ubifs_init_authentication':
fs/ubifs/auth.c:249:16: error: implicit declaration of function 'request_key'; did you mean 'request_irq'? [-Werror=implicit-function-declaration]
  keyring_key = request_key(&key_type_logon, c->auth_key_name, NULL);

Fixes: d8a22773a1 ("ubifs: Enable authentication support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-12-13 22:09:07 +01:00
Geert Uytterhoeven
aa3d31e08c ubifs: CONFIG_UBIFS_FS_AUTHENTICATION should depend on UBIFS_FS
Instead of adding yet another dependency on UBIFS_FS, wrap the whole
block of ubifs config options in a single "if UBIFS_FS".

Fixes: d8a22773a1 ("ubifs: Enable authentication support")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-12-13 22:09:07 +01:00
Arnd Bergmann
eb66eff663 ubifs: replay: Fix high stack usage
Having two shash descriptors on the stack cause a very significant kernel
stack usage that can cross the warning threshold:

fs/ubifs/replay.c: In function 'authenticate_sleb':
fs/ubifs/replay.c:633:1: error: the frame size of 1144 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]

Normally, gcc optimizes the out, but with CONFIG_CC_OPTIMIZE_FOR_DEBUGGING,
it does not. Splitting the two stack allocations into separate functions
means that they will use the same memory again. In normal configurations
(optimizing for size or performance), those should get inlined and we get
the same behavior as before.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-12-13 22:07:56 +01:00
Darrick J. Wong
64bafd2f1e xfs: require both realtime inodes to mount
Since mkfs always formats the filesystem with the realtime bitmap and
summary inodes immediately after the root directory, we should expect
that both of them are present and loadable, even if there isn't a
realtime volume attached.  There's no reason to skip this if rbmino ==
NULLFSINO; in fact, this causes an immediate crash if the there /is/ a
realtime volume and someone writes to it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
2018-12-13 12:03:45 -08:00
Linus Torvalds
e6333d72cb overlayfs fixes for 4.20-rc7
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Merge tag 'ovl-fixes-4.20-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs

Pull overlayfs fixes from Miklos Szeredi:
 "Needed to revert a patch, because it possibly introduces a security
  hole. Since the patch is basically a conceptual cleanup, not a bug
  fix, it's safe to revert. I'm not giving up on this, and discussions
  seemed to have reached an agreement over how to move forward, but that
  can wait 'till the next release.

  The other two patches are fixes for bugs introduced in recent
  releases"

* tag 'ovl-fixes-4.20-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  Revert "ovl: relax permission checking on underlying layers"
  ovl: fix decode of dir file handle with multi lower layers
  ovl: fix missing override creds in link of a metacopy upper
2018-12-12 18:19:44 -08:00
Linus Torvalds
70f4828201 fuse fixes for 4.20-rc7
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Merge tag 'fuse-fixes-4.20-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse

Pull fuse fixes from Miklos Szeredi:
 "There's one patch fixing a minor but long lived bug, the others are
  fixing regressions introduced in this cycle"

* tag 'fuse-fixes-4.20-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: continue to send FUSE_RELEASEDIR when FUSE_OPEN returns ENOSYS
  fuse: Fix memory leak in fuse_dev_free()
  fuse: fix revalidation of attributes for permission check
  fuse: fix fsync on directory
  fuse: Add bad inode check in fuse_destroy_inode()
2018-12-12 18:17:35 -08:00
Omar Sandoval
355e353213 xfs: cache minimum realtime summary level
The realtime summary is a two-dimensional array on disk, effectively:

u32 rsum[log2(number of realtime extents) + 1][number of blocks in the bitmap]

rsum[log][bbno] is the number of extents of size 2**log which start in
bitmap block bbno.

xfs_rtallocate_extent_near() uses xfs_rtany_summary() to check whether
rsum[log][bbno] != 0 for any log level. However, the summary array is
stored in row-major order (i.e., like an array in C), so all of these
entries are not adjacent, but rather spread across the entire summary
file. In the worst case (a full bitmap block), xfs_rtany_summary() has
to check every level.

This means that on a moderately-used realtime device, an allocation will
waste a lot of time finding, reading, and releasing buffers for the
realtime summary. In particular, one of our storage services (which runs
on servers with 8 very slow CPUs and 15 8 TB XFS realtime filesystems)
spends almost 5% of its CPU cycles in xfs_rtbuf_get() and
xfs_trans_brelse() called from xfs_rtany_summary().

One solution would be to also store the summary with the dimensions
swapped. However, this would require a disk format change to a very old
component of XFS.

Instead, we can cache the minimum size which contains any extents. We do
so lazily; rather than guaranteeing that the cache contains the precise
minimum, it always contains a loose lower bound which we tighten when we
read or update a summary block. This only uses a few kilobytes of memory
and is already serialized via the realtime bitmap and summary inode
locks, so the cost is minimal. With this change, the same workload only
spends 0.2% of its CPU cycles in the realtime allocator.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-12 08:47:17 -08:00
Darrick J. Wong
2c2d9d3a20 xfs: count inode blocks correctly in inobt scrub
A big block filesystem might require more than one inobt record to cover
all the inodes in the block.  In these cases it is not correct to round
the irec count up to the nearest block because this causes us to
overestimate the number of inode blocks we expect to find.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-12-12 08:47:17 -08:00
Darrick J. Wong
c1b4a321ed xfs: precalculate cluster alignment in inodes and blocks
Store the inode cluster alignment information in units of inodes and
blocks in the mount data so that we don't have to keep recalculating
them.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-12-12 08:47:17 -08:00
Darrick J. Wong
83dcdb4469 xfs: precalculate inodes and blocks per inode cluster
Store the number of inodes and blocks per inode cluster in the mount
data so that we don't have to keep recalculating them.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-12-12 08:47:17 -08:00
Darrick J. Wong
43004b2a8d xfs: add a block to inode count converter
Add new helpers to convert units of fs blocks into inodes, and AG blocks
into AG inodes, respectively.  Convert all the open-coded conversions
and XFS_OFFBNO_TO_AGINO(, , 0) calls to use them, as appropriate.  The
OFFBNO_TO_AGINO macro is retained for xfs_repair.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-12-12 08:47:16 -08:00
Darrick J. Wong
7280fedaf3 xfs: remove xfs_rmap_ag_owner and friends
Owner information for static fs metadata can be defined readonly at
build time because it never changes across filesystems.  This enables us
to reduce stack usage (particularly in scrub) because we can use the
statically defined oinfo structures.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-12-12 08:47:16 -08:00
Darrick J. Wong
66e3237e72 xfs: const-ify xfs_owner_info arguments
Only certain functions actually change the contents of an
xfs_owner_info; the rest can accept a const struct pointer.  This will
enable us to save stack space by hoisting static owner info types to
be const global variables.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-12-12 08:47:16 -08:00
Darrick J. Wong
02b100fb83 xfs: streamline defer op type handling
There's no need to bundle a pointer to the defer op type into the defer
op control structure.  Instead, store the defer op type enum, which
enables us to shorten some of the lines.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-12-12 08:47:16 -08:00
Darrick J. Wong
bc9f2b7c8a xfs: idiotproof defer op type configuration
Recently, we forgot to port a new defer op type to xfsprogs, which
caused us some userspace pain.  Reorganize the way we make libxfs
clients supply defer op type information so that all type information
has to be provided at build time instead of risky runtime dynamic
configuration.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-12-12 08:47:16 -08:00
Dave Chinner
43feeea88c xfs: zero length symlinks are not valid
A log recovery failure has been reproduced where a symlink inode has
a zero length in extent form. It was caused by a shutdown during a
combined fstress+fsmark workload.

The underlying problem is the issue in xfs_inactive_symlink(): the
inode is unlocked between the symlink inactivation/truncation and
the inode being freed. This opens a window for the inode to be
written to disk before it xfs_ifree() removes it from the unlinked
list, marks it free in the inobt and zeros the mode.

For shortform inodes, the fix is simple. xfs_ifree() clears the data
fork state, so there's no need to do it in xfs_inactive_symlink().
This means the shortform fork verifier will not see a zero length
data fork as it mirrors the inode size through to xfs_ifree()), and
hence if the inode gets written back and the fork verifiers are run
they will still see a fork that matches the on-disk inode size.

For extent form (remote) symlinks, it is a little more tricky. Here
we explicitly set the inode size to zero, so the above race can lead
to zero length symlinks on disk. Because the inode is unlinked at
this point (i.e. on the unlinked list) and unreferenced, it can
never be seen again by a user. Hence when we set the inode size to
zeor, also change the type to S_IFREG. xfs_ifree() expects S_IFREG
inodes to be of zero length, and so this avoids all the problems of
zero length symlinks ever hitting the disk. It also avoids the
problem of needing to handle zero length symlink inodes in log
recovery to replay the extent free intents and the remaining
deferops to free the extents the symlink used.

Also add a couple of asserts to warn us if zero length symlinks end
up in either the symlink create or inactivation paths.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-12 08:47:15 -08:00
Colin Ian King
8c4ce794ee xfs: clean up indentation issues, remove an unwanted space
There is a statement that has an unwanted space in the indentation.
Remove it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-12 08:46:20 -08:00
Pan Bian
fe5ed6c22e xfs: libxfs: move xfs_perag_put late
The function xfs_alloc_get_freelist calls xfs_perag_put to drop the
reference. However, pag->pagf_btreeblks is read and written after the
put operation. This patch moves the put operation later.

Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
[darrick: minor changelog edits]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-12 08:46:20 -08:00
Darrick J. Wong
d6f215f359 xfs: split up the xfs_reflink_end_cow work into smaller transactions
In xfs_reflink_end_cow, we allocate a single transaction for the entire
end_cow operation and then loop the CoW fork mappings to move them to
the data fork.  This design fails on a heavily fragmented filesystem
where an inode's data fork has exactly one more extent than would fit in
an extents-format fork, because the unmap can collapse the data fork
into extents format (freeing the bmbt block) but the remap can expand
the data fork back into a (newly allocated) bmbt block.  If the number
of extents we end up remapping is large, we can overflow the block
reservation because we reserved blocks assuming that we were adding
mappings into an already-cleared area of the data fork.

Let's say we have 8 extents in the data fork, 8 extents in the CoW fork,
and the data fork can hold at most 7 extents before needing to convert
to btree format; and that blocks A-P are discontiguous single-block
extents:

   0......7
D: ABCDEFGH
C: IJKLMNOP

When a write to file blocks 0-7 completes, we must remap I-P into the
data fork.  We start by removing H from the btree-format data fork.  Now
we have 7 extents, so we convert the fork to extents format, freeing the
bmbt block.   We then move P into the data fork and it now has 8 extents
again.  We must convert the data fork back to btree format, requiring a
block allocation.  If we repeat this sequence for blocks 6-5-4-3-2-1-0,
we'll need a total of 8 block allocations to remap all 8 blocks.  We
reserved only enough blocks to handle one btree split (5 blocks on a 4k
block filesystem), which means we overflow the block reservation.

To fix this issue, create a separate helper function to remap a single
extent, and change _reflink_end_cow to call it in a tight loop over the
entire range we're completing.  As a side effect this also removes the
size restrictions on how many extents we can end_cow at a time, though
nobody ever hit that.  It is not reasonable to reserve N blocks to remap
N blocks.

Note that this can be reproduced after ~320 million fsx ops while
running generic/938 (long soak directio fsx exerciser):

XFS: Assertion failed: tp->t_blk_res >= tp->t_blk_res_used, file: fs/xfs/xfs_trans.c, line: 116
<machine registers snipped>
Call Trace:
 xfs_trans_dup+0x211/0x250 [xfs]
 xfs_trans_roll+0x6d/0x180 [xfs]
 xfs_defer_trans_roll+0x10c/0x3b0 [xfs]
 xfs_defer_finish_noroll+0xdf/0x740 [xfs]
 xfs_defer_finish+0x13/0x70 [xfs]
 xfs_reflink_end_cow+0x2c6/0x680 [xfs]
 xfs_dio_write_end_io+0x115/0x220 [xfs]
 iomap_dio_complete+0x3f/0x130
 iomap_dio_rw+0x3c3/0x420
 xfs_file_dio_aio_write+0x132/0x3c0 [xfs]
 xfs_file_write_iter+0x8b/0xc0 [xfs]
 __vfs_write+0x193/0x1f0
 vfs_write+0xba/0x1c0
 ksys_write+0x52/0xc0
 do_syscall_64+0x50/0x160
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-12-12 08:46:19 -08:00
Jan Kara
d288d95842 udf: Fix BUG on corrupted inode
When inode is corrupted so that extent type is invalid, some functions
(such as udf_truncate_extents()) will just BUG. Check that extent type
is valid when loading the inode to memory.

Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2018-12-12 15:48:49 +01:00
Kamal Heib
3023a1e936 RDMA: Start use ib_device_ops
Make all the required change to start use the ib_device_ops structure.

Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-12-12 07:40:16 -07:00
Bob Peterson
27a2660f1e gfs2: Dump nrpages for inodes and their glocks
This patch is based on an idea from Steve Whitehouse. The idea is
to dump the number of pages for inodes in the glock dumps.
The additional locking required me to drop const from quite a few
places.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-12-12 12:33:23 +01:00
Andreas Gruenbacher
2d29f6b96d gfs2: Fix loop in gfs2_rbm_find
Fix the resource group wrap-around logic in gfs2_rbm_find that commit
e579ed4f44 broke.  The bug can lead to unnecessary repeated scanning of the
same bitmaps; there is a risk that future changes will turn this into an
endless loop.

Fixes: e579ed4f44 ("GFS2: Introduce rbm field bii")
Cc: stable@vger.kernel.org # v3.13+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-12-12 12:31:40 +01:00
Chad Austin
2e64ff154c fuse: continue to send FUSE_RELEASEDIR when FUSE_OPEN returns ENOSYS
When FUSE_OPEN returns ENOSYS, the no_open bit is set on the connection.

Because the FUSE_RELEASE and FUSE_RELEASEDIR paths share code, this
incorrectly caused the FUSE_RELEASEDIR request to be dropped and never sent
to userspace.

Pass an isdir bool to distinguish between FUSE_RELEASE and FUSE_RELEASEDIR
inside of fuse_file_put.

Fixes: 7678ac5061 ("fuse: support clients that don't implement 'open'")
Cc: <stable@vger.kernel.org> # v3.14
Signed-off-by: Chad Austin <chadaustin@fb.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-12-11 21:47:28 +01:00
Andreas Gruenbacher
6ff9b09e00 gfs2: Get rid of potential double-freeing in gfs2_create_inode
In gfs2_create_inode, after setting and releasing the acl / default_acl, the
acl / default_acl pointers are not set to NULL as they should be.  In that
state, when the function reaches label fail_free_acls, gfs2_create_inode will
try to release the same acls again.

Fix that by setting the pointers to NULL after releasing the acls.  Slightly
simplify the logic.  Also, posix_acl_release checks for NULL already, so
there is no need to duplicate those checks here.

Fixes: e01580bf9e ("gfs2: use generic posix ACL infrastructure")
Reported-by: Pan Bian <bianpan2016@163.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-12-11 21:44:29 +01:00
Bob Peterson
cbbe76c8bb gfs2: Remove vestigial bd_ops
Field bd_ops was set but never used, so I removed it, and all
code supporting it.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-12-11 21:43:58 +01:00
Jeff Moyer
0afa996483 aio: fix spectre gadget in lookup_ioctx
Matthew pointed out that the ioctx_table is susceptible to spectre v1,
because the index can be controlled by an attacker.  The below patch
should mitigate the attack for all of the aio system calls.

Reported-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-12-11 14:32:14 -05:00
Jeff Moyer
a538e3ff9d aio: fix spectre gadget in lookup_ioctx
Matthew pointed out that the ioctx_table is susceptible to spectre v1,
because the index can be controlled by an attacker.  The below patch
should mitigate the attack for all of the aio system calls.

Cc: stable@vger.kernel.org
Reported-by: Matthew Wilcox <willy@infradead.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-11 11:45:50 -07:00
Luis Henriques
6f9718fe41 ceph: make 'nocopyfrom' a default mount option
Since we found a problem with the 'copy-from' operation after objects have
been truncated, offloading object copies to OSDs should be discouraged
until the issue is fixed.

Thus, this patch adds the 'nocopyfrom' mount option to the default mount
options which effectily means that remote copies won't be done in
copy_file_range unless they are explicitly enabled at mount time.

[ Adjust ceph_show_options() accordingly. ]

Link: https://tracker.ceph.com/issues/37378
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2018-12-11 18:22:17 +01:00
Abhi Das
2a5f14f279 gfs2: read journal in large chunks to locate the head
Use bio(s) to read in the journal sequentially in large chunks and
locate the head of the journal.

This version addresses the issues Christoph pointed out w.r.t error handling
and using deprecated API.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
2018-12-11 17:50:36 +01:00
Abhi Das
40e0e61e36 gfs2: add a helper function to get_log_header that can be used elsewhere
Move and re-order the error checks and hash/crc computations into another
function __get_log_header() so it can be used in scenarios where buffer_heads
are not being used for the log header.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-12-11 17:50:36 +01:00
Abhi Das
5b84609532 gfs2: changes to gfs2_log_XXX_bio
Change gfs2_log_XXX_bio family of functions so they can be used
with different bios, not just sdp->sd_log_bio.

This patch also contains some clean up suggested by Andreas.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-12-11 17:50:36 +01:00
Abhi Das
98583b3e87 gfs2: add more timing info to journal recovery process
Tells you how many milliseconds map_journal_extents and find_jhead
take.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-12-11 17:50:36 +01:00
Andreas Gruenbacher
0ebbe4f974 gfs2: Fix the gfs2_invalidatepage description
The comment incorrectly states that the function always returns 0.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-12-11 17:50:35 +01:00
Andreas Gruenbacher
977767a7e1 gfs2: Clean up gfs2_is_{ordered,writeback}
The gfs2_is_ordered and gfs2_is_writeback checks are weird in that they
implicitly check for !gfs2_is_jdata.  This makes understanding how to
use those functions correctly a challenge.  Clean this up by making
gfs2_is_ordered and gfs2_is_writeback take a super block instead of an
inode and by removing the implicit !gfs2_is_jdata checks.  Update the
callers accordingly.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-12-11 17:50:35 +01:00
Nikolay Borisov
ac9498d686 fanotify: Use inode_is_open_for_write
Use the aptly named function rather than opencoding i_writecount check.
No functional changes.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2018-12-11 10:55:45 +01:00
Chanho Min
4addd2640f exec: make prepare_bprm_creds static
prepare_bprm_creds is not used outside exec.c, so there's no reason for it
to have external linkage.

Signed-off-by: Chanho Min <chanho.min@lge.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-12-10 04:11:06 -05:00
Takeshi Misawa
d72f70da60 fuse: Fix memory leak in fuse_dev_free()
When ntfs is unmounted, the following leak is
reported by kmemleak.

kmemleak report:

unreferenced object 0xffff880052bf4400 (size 4096):
  comm "mount.ntfs", pid 16530, jiffies 4294861127 (age 3215.836s)
  hex dump (first 32 bytes):
    00 44 bf 52 00 88 ff ff 00 44 bf 52 00 88 ff ff  .D.R.....D.R....
    10 44 bf 52 00 88 ff ff 10 44 bf 52 00 88 ff ff  .D.R.....D.R....
  backtrace:
    [<00000000bf4a2f8d>] fuse_fill_super+0xb22/0x1da0 [fuse]
    [<000000004dde0f0c>] mount_bdev+0x263/0x320
    [<0000000025aebc66>] mount_fs+0x82/0x2bf
    [<0000000042c5a6be>] vfs_kern_mount.part.33+0xbf/0x480
    [<00000000ed10cd5b>] do_mount+0x3de/0x2ad0
    [<00000000d59ff068>] ksys_mount+0xba/0xd0
    [<000000001bda1bcc>] __x64_sys_mount+0xba/0x150
    [<00000000ebe26304>] do_syscall_64+0x151/0x490
    [<00000000d25f2b42>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
    [<000000002e0abd2c>] 0xffffffffffffffff

fuse_dev_alloc() allocate fud->pq.processing.
But this hash table is not freed.

Fix this by freeing fud->pq.processing.

Signed-off-by: Takeshi Misawa <jeliantsurux@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: be2ff42c5d ("fuse: Use hash table to link processing request")
2018-12-10 09:57:54 +01:00
Chengguang Xu
0a1e8258a4 ext4: compare old and new mode before setting update_mode flag
If new mode is the same as old mode we don't have to reset
inode mode in the rest of the code, so compare old and new
mode before setting update_mode flag.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-12-10 00:22:38 -05:00
Jens Axboe
96f774106e Linux 4.20-rc6
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Merge tag 'v4.20-rc6' into for-4.21/block

Pull in v4.20-rc6 to resolve the conflict in NVMe, but also to get the
two corruption fixes. We're going to be overhauling the direct dispatch
path, and we need to do that on top of the changes we made for that
in mainline.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-09 17:45:40 -07:00
Linus Torvalds
bc4caf186f a fix for smb3 direct i/o, a fix for CIFS DFS for stable and a minor cifs Kconfig fix
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Merge tag '4.20-rc5-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "Three small fixes: a fix for smb3 direct i/o, a fix for CIFS DFS for
  stable and a minor cifs Kconfig fix"

* tag '4.20-rc5-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Avoid returning EBUSY to upper layer VFS
  cifs: Fix separator when building path from dentry
  cifs: In Kconfig CONFIG_CIFS_POSIX needs depends on legacy (insecure cifs)
2018-12-09 10:15:13 -08:00
Linus Torvalds
fa82dcbf2a dax fixes 4.20-rc6
* Fix the Xarray conversion of fsdax to properly handle
 dax_lock_mapping_entry() in the presense of pmd entries.
 
 * Fix inode destruction racing a new lock request.
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Merge tag 'dax-fixes-4.20-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull dax fixes from Dan Williams:
 "The last of the known regression fixes and fallout from the Xarray
  conversion of the filesystem-dax implementation.

  On the path to debugging why the dax memory-failure injection test
  started failing after the Xarray conversion a couple more fixes for
  the dax_lock_mapping_entry(), now called dax_lock_page(), surfaced.
  Those plus the bug that started the hunt are now addressed. These
  patches have appeared in a -next release with no issues reported.

  Note the touches to mm/memory-failure.c are just the conversion to the
  new function signature for dax_lock_page().

  Summary:

   - Fix the Xarray conversion of fsdax to properly handle
     dax_lock_mapping_entry() in the presense of pmd entries

   - Fix inode destruction racing a new lock request"

* tag 'dax-fixes-4.20-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: Fix unlock mismatch with updated API
  dax: Don't access a freed inode
  dax: Check page->mapping isn't NULL
2018-12-09 09:54:04 -08:00
Linus Torvalds
f896adc42d Changes since last update:
- Fix broken project quota inode counts
 - Fix incorrect PAGE_MASK/PAGE_SIZE usage
 - Fix incorrect return value in btree verifier
 - Fix WARN_ON remap flags false positive
 - Fix splice read overflows
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Merge tag 'xfs-4.20-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fixes from Darrick Wong:
 "Here are hopefully the last set of fixes for 4.20.

  There's a fix for a longstanding statfs reporting problem with project
  quotas, a correction for page cache invalidation behaviors when
  fallocating near EOF, and a fix for a broken metadata verifier return
  code.

  Finally, the most important fix is to the pipe splicing code (aka the
  generic copy_file_range fallback) to avoid pointless short directio
  reads by only asking the filesystem for as much data as there are
  available pages in the pipe buffer. Our previous fix (simulated short
  directio reads because the number of pages didn't match the length of
  the read requested) caused subtle problems on overlayfs, so that part
  is reverted.

  Anyhow, this series passes fstests -g all on xfs and overlay+xfs, and
  has passed 17 billion fsx operations problem-free since I started
  testing

  Summary:

   - Fix broken project quota inode counts

   - Fix incorrect PAGE_MASK/PAGE_SIZE usage

   - Fix incorrect return value in btree verifier

   - Fix WARN_ON remap flags false positive

   - Fix splice read overflows"

* tag 'xfs-4.20-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: partially revert 4721a60109 (simulated directio short read on EFAULT)
  splice: don't read more than available pipe space
  vfs: allow some remap flags to be passed to vfs_clone_file_range
  xfs: fix inverted return from xfs_btree_sblock_verify_crc
  xfs: fix PAGE_MASK usage in xfs_free_file_space
  fs/xfs: fix f_ffree value for statfs when project quota is set
2018-12-08 11:25:02 -08:00
Dennis Zhou
fd42df305f blkcg: associate writeback bios with a blkg
One of the goals of this series is to remove a separate reference to
the css of the bio. This can and should be accessed via bio_blkcg(). In
this patch, wbc_init_bio() now requires a bio to have a device
associated with it.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:37 -07:00
NeilBrown
7bbd1fc0e9 fs/locks: remove unnecessary white space.
- spaces before tabs,
 - spaces at the end of lines,
 - multiple blank lines,
 - blank lines before EXPORT_SYMBOL,
can all go.

Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-12-07 06:51:00 -05:00
NeilBrown
cb03f94ffb fs/locks: merge posix_unblock_lock() and locks_delete_block()
posix_unblock_lock() is not specific to posix locks, and behaves
nearly identically to locks_delete_block() - the former returning a
status while the later doesn't.

So discard posix_unblock_lock() and use locks_delete_block() instead,
after giving that function an appropriate return value.

Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-12-07 06:50:56 -05:00
NeilBrown
fd7732e033 fs/locks: create a tree of dependent requests.
When we find an existing lock which conflicts with a request,
and the request wants to wait, we currently add the request
to a list.  When the lock is removed, the whole list is woken.
This can cause the thundering-herd problem.
To reduce the problem, we make use of the (new) fact that
a pending request can itself have a list of blocked requests.
When we find a conflict, we look through the existing blocked requests.
If any one of them blocks the new request, the new request is attached
below that request, otherwise it is added to the list of blocked
requests, which are now known to be mutually non-conflicting.

This way, when the lock is released, only a set of non-conflicting
locks will be woken, the rest can stay asleep.
If the lock request cannot be granted and the request needs to be
requeued, all the other requests it blocks will then be woken

To make this more concrete:

  If you have a many-core machine, and have many threads all wanting to
  briefly lock a give file (udev is known to do this), you can get quite
  poor performance.

  When one thread releases a lock, it wakes up all other threads that
  are waiting (classic thundering-herd) - one will get the lock and the
  others go to sleep.
  When you have few cores, this is not very noticeable: by the time the
  4th or 5th thread gets enough CPU time to try to claim the lock, the
  earlier threads have claimed it, done what was needed, and released.
  So with few cores, many of the threads don't end up contending.
  With 50+ cores, lost of threads can get the CPU at the same time,
  and the contention can easily be measured.

  This patchset creates a tree of pending lock requests in which siblings
  don't conflict and each lock request does conflict with its parent.
  When a lock is released, only requests which don't conflict with each
  other a woken.

  Testing shows that lock-acquisitions-per-second is now fairly stable
  even as the number of contending process goes to 1000.  Without this
  patch, locks-per-second drops off steeply after a few 10s of
  processes.

  There is a small cost to this extra complexity.
  At 20 processes running a particular test on 72 cores, the lock
  acquisitions per second drops from 1.8 million to 1.4 million with
  this patch.  For 100 processes, this patch still provides 1.4 million
  while without this patch there are about 700,000.

Reported-and-tested-by: Martin Wilck <mwilck@suse.de>
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-12-07 06:49:24 -05:00
NeilBrown
c0e1590897 fs/locks: change all *_conflict() functions to return bool.
posix_locks_conflict() and flock_locks_conflict() both return int.
leases_conflict() returns bool.

This inconsistency will cause problems for the next patch if not
fixed.

So change posix_locks_conflict() and flock_locks_conflict() to return
bool.
Also change the locks_conflict() helper.

And convert some
   return (foo);
to
   return foo;

Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-12-07 06:49:24 -05:00
NeilBrown
16306a61d3 fs/locks: always delete_block after waiting.
Now that requests can block other requests, we
need to be careful to always clean up those blocked
requests.
Any time that we wait for a request, we might have
other requests attached, and when we stop waiting,
we must clean them up.
If the lock was granted, the requests might have been
moved to the new lock, though when merged with a
pre-exiting lock, this might not happen.
In all cases we don't want blocked locks to remain
attached, so we remove them to be safe.

Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
Tested-by: syzbot+a4a3d526b4157113ec6a@syzkaller.appspotmail.com
Tested-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-12-07 06:49:17 -05:00
Long Li
6ac79291fb CIFS: Avoid returning EBUSY to upper layer VFS
EBUSY is not handled by VFS, and will be passed to user-mode. This is not
correct as we need to wait for more credits.

This patch also fixes a bug where rsize or wsize is used uninitialized when
the call to server->ops->wait_mtu_credits() fails.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-12-07 00:59:23 -06:00
Linus Torvalds
7f80c7325b NFS client bugfixes for Linux 4.20
Highlights include:
 
 Stable fixes:
  - Fix a page leak when using RPCSEC_GSS/krb5p to encrypt data.
 
 Bugfixes:
  - Fix a regression that causes the RPC receive code to hang
  - Fix call_connect_status() so that it handles tasks that got transmitted
    while queued waiting for the socket lock.
  - Fix a memory leak in call_encode()
  - Fix several other connect races.
  - Fix receive code error handling.
  - Use the discard iterator rather than MSG_TRUNC for compatibility with
    AF_UNIX/AF_LOCAL sockets.
  - nfs: don't dirty kernel pages read by direct-io
  - pnfs/Flexfiles fix to enforce per-mirror stateid only for NFSv4 data
    servers
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Merge tag 'nfs-for-4.20-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:
 "This is mainly fallout from the updates to the SUNRPC code that is
  being triggered from less common combinations of NFS mount options.

  Highlights include:

  Stable fixes:
   - Fix a page leak when using RPCSEC_GSS/krb5p to encrypt data.

  Bugfixes:
   - Fix a regression that causes the RPC receive code to hang
   - Fix call_connect_status() so that it handles tasks that got
     transmitted while queued waiting for the socket lock.
   - Fix a memory leak in call_encode()
   - Fix several other connect races.
   - Fix receive code error handling.
   - Use the discard iterator rather than MSG_TRUNC for compatibility
     with AF_UNIX/AF_LOCAL sockets.
   - nfs: don't dirty kernel pages read by direct-io
   - pnfs/Flexfiles fix to enforce per-mirror stateid only for NFSv4
     data servers"

* tag 'nfs-for-4.20-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  SUNRPC: Don't force a redundant disconnection in xs_read_stream()
  SUNRPC: Fix up socket polling
  SUNRPC: Use the discard iterator rather than MSG_TRUNC
  SUNRPC: Treat EFAULT as a truncated message in xs_read_stream_request()
  SUNRPC: Fix up handling of the XDRBUF_SPARSE_PAGES flag
  SUNRPC: Fix RPC receive hangs
  SUNRPC: Fix a potential race in xprt_connect()
  SUNRPC: Fix a memory leak in call_encode()
  SUNRPC: Fix leak of krb5p encode pages
  SUNRPC: call_connect_status() must handle tasks that got transmitted
  nfs: don't dirty kernel pages read by direct-io
  flexfiles: enforce per-mirror stateid only for v4 DSes
2018-12-06 18:57:04 -08:00
Deepa Dinamani
7a35397f8c io_pgetevents: use __kernel_timespec
struct timespec is not y2038 safe.
struct __kernel_timespec is the new y2038 safe structure for all
syscalls that are using struct timespec.
Update io_pgetevents interfaces to use struct __kernel_timespec.

sigset_t also has different representations on 32 bit and 64 bit
architectures. Hence, we need to support the following different
syscalls:

New y2038 safe syscalls:
(Controlled by CONFIG_64BIT_TIME for 32 bit ABIs)

Native 64 bit(unchanged) and native 32 bit : sys_io_pgetevents
Compat : compat_sys_io_pgetevents_time64

Older y2038 unsafe syscalls:
(Controlled by CONFIG_32BIT_COMPAT_TIME for 32 bit ABIs)

Native 32 bit : sys_io_pgetevents_time32
Compat : compat_sys_io_pgetevents

Note that io_getevents syscalls do not have a y2038 safe solution.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-06 17:23:31 +01:00
Deepa Dinamani
e024707bcc pselect6: use __kernel_timespec
struct timespec is not y2038 safe.
struct __kernel_timespec is the new y2038 safe structure for all
syscalls that are using struct timespec.
Update pselect interfaces to use struct __kernel_timespec.

sigset_t also has different representations on 32 bit and 64 bit
architectures. Hence, we need to support the following different
syscalls:

New y2038 safe syscalls:
(Controlled by CONFIG_64BIT_TIME for 32 bit ABIs)

Native 64 bit(unchanged) and native 32 bit : sys_pselect6
Compat : compat_sys_pselect6_time64

Older y2038 unsafe syscalls:
(Controlled by CONFIG_32BIT_COMPAT_TIME for 32 bit ABIs)

Native 32 bit : pselect6_time32
Compat : compat_sys_pselect6

Note that all other versions of select syscalls will not have
y2038 safe versions.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-06 17:23:18 +01:00
Deepa Dinamani
8bd27a3004 ppoll: use __kernel_timespec
struct timespec is not y2038 safe.
struct __kernel_timespec is the new y2038 safe structure for all
syscalls that are using struct timespec.
Update ppoll interfaces to use struct __kernel_timespec.

sigset_t also has different representations on 32 bit and 64 bit
architectures. Hence, we need to support the following different
syscalls:

New y2038 safe syscalls:
(Controlled by CONFIG_64BIT_TIME for 32 bit ABIs)

Native 64 bit(unchanged) and native 32 bit : sys_ppoll
Compat : compat_sys_ppoll_time64

Older y2038 unsafe syscalls:
(Controlled by CONFIG_32BIT_COMPAT_TIME for 32 bit ABIs)

Native 32 bit : ppoll_time32
Compat : compat_sys_ppoll

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-06 17:23:05 +01:00
Deepa Dinamani
854a6ed568 signal: Add restore_user_sigmask()
Refactor the logic to restore the sigmask before the syscall
returns into an api.
This is useful for versions of syscalls that pass in the
sigmask and expect the current->sigmask to be changed during
the execution and restored after the execution of the syscall.

With the advent of new y2038 syscalls in the subsequent patches,
we add two more new versions of the syscalls (for pselect, ppoll
and io_pgetevents) in addition to the existing native and compat
versions. Adding such an api reduces the logic that would need to
be replicated otherwise.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-06 17:22:53 +01:00
Deepa Dinamani
ded653ccbe signal: Add set_user_sigmask()
Refactor reading sigset from userspace and updating sigmask
into an api.

This is useful for versions of syscalls that pass in the
sigmask and expect the current->sigmask to be changed during,
and restored after, the execution of the syscall.

With the advent of new y2038 syscalls in the subsequent patches,
we add two more new versions of the syscalls (for pselect, ppoll,
and io_pgetevents) in addition to the existing native and compat
versions. Adding such an api reduces the logic that would need to
be replicated otherwise.

Note that the calls to sigprocmask() ignored the return value
from the api as the function only returns an error on an invalid
first argument that is hardcoded at these call sites.
The updated logic uses set_current_blocked() instead.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-06 17:22:38 +01:00
Paulo Alcantara
c988de29ca cifs: Fix separator when building path from dentry
Make sure to use the CIFS_DIR_SEP(cifs_sb) as path separator for
prefixpath too. Fixes a bug with smb1 UNIX extensions.

Fixes: a6b5058faf ("fs/cifs: make share unaccessible at root level mountable")
Signed-off-by: Paulo Alcantara <palcantara@suse.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2018-12-06 02:20:17 -06:00
Steve French
6e785302da cifs: In Kconfig CONFIG_CIFS_POSIX needs depends on legacy (insecure cifs)
Missing a dependency.  Shouldn't show cifs posix extensions
in Kconfig if CONFIG_CIFS_ALLOW_INSECURE_DIALECTS (ie SMB1
protocol) is disabled.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-12-06 02:20:14 -06:00
Dave Airlie
467e8a516d Final drm/i915 changes for v4.21:
- ICL DSI video mode enabling (Madhav, Vandita, Jani, Imre)
 - eDP sink count fix (José)
 - PSR fixes (José)
 - DRM DP helper and i915 DSC enabling (Manasi, Gaurav, Anusha)
 - DP FEC enabling (Anusha)
 - SKL+ watermark/ddb programming improvements (Ville)
 - Pixel format fixes (Ville)
 - Selftest updates (Chris, Tvrtko)
 - GT and engine workaround improvements (Tvrtko)
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Merge tag 'drm-intel-next-2018-12-04' of git://anongit.freedesktop.org/drm/drm-intel into drm-next

Final drm/i915 changes for v4.21:
- ICL DSI video mode enabling (Madhav, Vandita, Jani, Imre)
- eDP sink count fix (José)
- PSR fixes (José)
- DRM DP helper and i915 DSC enabling (Manasi, Gaurav, Anusha)
- DP FEC enabling (Anusha)
- SKL+ watermark/ddb programming improvements (Ville)
- Pixel format fixes (Ville)
- Selftest updates (Chris, Tvrtko)
- GT and engine workaround improvements (Tvrtko)

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/87va496uoe.fsf@intel.com
2018-12-06 09:17:51 +10:00
Linus Torvalds
d089709045 for-4.20-rc5-tag
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Merge tag 'for-4.20-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fix from David Sterba:
 "A patch in 4.19 introduced a sanity check that was too strict and a
  filesystem cannot be mounted.

  This happens for filesystems with more than 10 devices and has been
  reported by a few users so we need the fix to propagate to stable"

* tag 'for-4.20-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: tree-checker: Don't check max block group size as current max chunk size limit is unreliable
2018-12-05 09:58:17 -08:00
Kees Cook
5b03a472b4 fanotify: Make sure to check event_len when copying
As a precaution, make sure we check event_len when copying to userspace.
Based on old feedback: https://lkml.kernel.org/r/542D9FE5.3010009@gmx.de

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jan Kara <jack@suse.cz>
2018-12-05 12:47:22 +01:00
Matthew Wilcox
27359fd6e5 dax: Fix unlock mismatch with updated API
Internal to dax_unlock_mapping_entry(), dax_unlock_entry() is used to
store a replacement entry in the Xarray at the given xas-index with the
DAX_LOCKED bit clear. When called, dax_unlock_entry() expects the unlocked
value of the entry relative to the current Xarray state to be specified.

In most contexts dax_unlock_entry() is operating in the same scope as
the matched dax_lock_entry(). However, in the dax_unlock_mapping_entry()
case the implementation needs to recall the original entry. In the case
where the original entry is a 'pmd' entry it is possible that the pfn
performed to do the lookup is misaligned to the value retrieved in the
Xarray.

Change the api to return the unlock cookie from dax_lock_page() and pass
it to dax_unlock_page(). This fixes a bug where dax_unlock_page() was
assuming that the page was PMD-aligned if the entry was a PMD entry with
signatures like:

 WARNING: CPU: 38 PID: 1396 at fs/dax.c:340 dax_insert_entry+0x2b2/0x2d0
 RIP: 0010:dax_insert_entry+0x2b2/0x2d0
 [..]
 Call Trace:
  dax_iomap_pte_fault.isra.41+0x791/0xde0
  ext4_dax_huge_fault+0x16f/0x1f0
  ? up_read+0x1c/0xa0
  __do_fault+0x1f/0x160
  __handle_mm_fault+0x1033/0x1490
  handle_mm_fault+0x18b/0x3d0

Link: https://lkml.kernel.org/r/20181130154902.GL10377@bombadil.infradead.org
Fixes: 9f32d22130 ("dax: Convert dax_lock_mapping_entry to XArray")
Reported-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-04 21:32:00 -08:00
zhengbin
255fbca651 nfsd: Return EPERM, not EACCES, in some SETATTR cases
As the man(2) page for utime/utimes states, EPERM is returned when the
second parameter of utime or utimes is not NULL, the caller's effective UID
does not match the owner of the file, and the caller is not privileged.

However, in a NFS directory mounted from knfsd, it will return EACCES
(from nfsd_setattr-> fh_verify->nfsd_permission).  This patch fixes
that.

Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-12-04 20:48:07 -05:00
Darrick J. Wong
8f67b5adc0 iomap: partially revert 4721a60109 (simulated directio short read on EFAULT)
In commit 4721a60109, we tried to fix a problem wherein directio reads
into a splice pipe will bounce EFAULT/EAGAIN all the way out to
userspace by simulating a zero-byte short read.  This happens because
some directio read implementations (xfs) will call
bio_iov_iter_get_pages to grab pipe buffer pages and issue asynchronous
reads, but as soon as we run out of pipe buffers that _get_pages call
returns EFAULT, which the splice code translates to EAGAIN and bounces
out to userspace.

In that commit, the iomap code catches the EFAULT and simulates a
zero-byte read, but that causes assertion errors on regular splice reads
because xfs doesn't allow short directio reads.  This causes infinite
splice() loops and assertion failures on generic/095 on overlayfs
because xfs only permit total success or total failure of a directio
operation.  The underlying issue in the pipe splice code has now been
fixed by changing the pipe splice loop to avoid avoid reading more data
than there is space in the pipe.

Therefore, it's no longer necessary to simulate the short directio, so
remove the hack from iomap.

Fixes: 4721a60109 ("iomap: dio data corruption and spurious errors when pipes fill")
Reported-by: Murphy Zhou <jencce.kernel@gmail.com>
Ranted-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-04 09:40:02 -08:00
Darrick J. Wong
1761444557 splice: don't read more than available pipe space
In commit 4721a60109, we tried to fix a problem wherein directio reads
into a splice pipe will bounce EFAULT/EAGAIN all the way out to
userspace by simulating a zero-byte short read.  This happens because
some directio read implementations (xfs) will call
bio_iov_iter_get_pages to grab pipe buffer pages and issue asynchronous
reads, but as soon as we run out of pipe buffers that _get_pages call
returns EFAULT, which the splice code translates to EAGAIN and bounces
out to userspace.

In that commit, the iomap code catches the EFAULT and simulates a
zero-byte read, but that causes assertion errors on regular splice reads
because xfs doesn't allow short directio reads.

The brokenness is compounded by splice_direct_to_actor immediately
bailing on do_splice_to returning <= 0 without ever calling ->actor
(which empties out the pipe), so if userspace calls back we'll EFAULT
again on the full pipe, and nothing ever gets copied.

Therefore, teach splice_direct_to_actor to clamp its requests to the
amount of free space in the pipe and remove the simulated short read
from the iomap directio code.

Fixes: 4721a60109 ("iomap: dio data corruption and spurious errors when pipes fill")
Reported-by: Murphy Zhou <jencce.kernel@gmail.com>
Ranted-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-04 08:50:49 -08:00
Darrick J. Wong
6744557b53 vfs: allow some remap flags to be passed to vfs_clone_file_range
In overlayfs, ovl_remap_file_range calls vfs_clone_file_range on the
lower filesystem's inode, passing through whatever remap flags it got
from its caller.  Since vfs_copy_file_range first tries a filesystem's
remap function with REMAP_FILE_CAN_SHORTEN, this can get passed through
to the second vfs_copy_file_range call, and this isn't an issue.
Change the WARN_ON to look only for the DEDUP flag.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-12-04 08:50:49 -08:00
Eric Sandeen
7d048df4e9 xfs: fix inverted return from xfs_btree_sblock_verify_crc
xfs_btree_sblock_verify_crc is a bool so should not be returning
a failaddr_t; worse, if xfs_log_check_lsn fails it returns
__this_address which looks like a boolean true (i.e. success)
to the caller.

(interestingly xfs_btree_lblock_verify_crc doesn't have the issue)

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-04 08:50:49 -08:00
Darrick J. Wong
a579121f94 xfs: fix PAGE_MASK usage in xfs_free_file_space
In commit e53c4b598, I *tried* to teach xfs to force writeback when we
fzero/fpunch right up to EOF so that if EOF is in the middle of a page,
the post-EOF part of the page gets zeroed before we return to userspace.
Unfortunately, I missed the part where PAGE_MASK is ~(PAGE_SIZE - 1),
which means that we totally fail to zero if we're fpunching and EOF is
within the first page.  Worse yet, the same PAGE_MASK thinko plagues the
filemap_write_and_wait_range call, so we'd initiate writeback of the
entire file, which (mostly) masked the thinko.

Drop the tricky PAGE_MASK and replace it with correct usage of PAGE_SIZE
and the proper rounding macros.

Fixes: e53c4b598 ("xfs: ensure post-EOF zeroing happens after zeroing part of a file")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-12-04 08:50:49 -08:00
Christoph Hellwig
154989e45f aio: clear IOCB_HIPRI
No one is going to poll for aio (yet), so we must clear the HIPRI
flag, as we would otherwise send it down the poll queues, where no
one will be polling for completions.

Signed-off-by: Christoph Hellwig <hch@lst.de>

IOCB_HIPRI, not RWF_HIPRI.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-04 09:39:06 -07:00
Jens Axboe
89d04ec349 Linux 4.20-rc5
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 DM3lal5M6zlUVkoYstqzpbR3MqUwgEnMfvoeMDC6mI9N4/+r2LkV7cRR8HzqQCCS
 jDfD69IzRGb52VSeJmbOrkxBWsR1Nn0t4Z3rEeLPxwaOoNpRc8H973MbAQ2FKMpY
 S4Y3jIK1dNiRRxdh52NupVkQF+djAUwkBuVk/rrvRJmTDij4la03cuCDAO+Di9lt
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 JtwhVCE=
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Merge tag 'v4.20-rc5' into for-4.21/block

Pull in v4.20-rc5, solving a conflict we'll otherwise get in aio.c and
also getting the merge fix that went into mainline that users are
hitting testing for-4.21/block and/or for-next.

* tag 'v4.20-rc5': (664 commits)
  Linux 4.20-rc5
  PCI: Fix incorrect value returned from pcie_get_speed_cap()
  MAINTAINERS: Update linux-mips mailing list address
  ocfs2: fix potential use after free
  mm/khugepaged: fix the xas_create_range() error path
  mm/khugepaged: collapse_shmem() do not crash on Compound
  mm/khugepaged: collapse_shmem() without freezing new_page
  mm/khugepaged: minor reorderings in collapse_shmem()
  mm/khugepaged: collapse_shmem() remember to clear holes
  mm/khugepaged: fix crashes due to misaccounted holes
  mm/khugepaged: collapse_shmem() stop if punched or truncated
  mm/huge_memory: fix lockdep complaint on 32-bit i_size_read()
  mm/huge_memory: splitting set mapping+index before unfreeze
  mm/huge_memory: rename freeze_page() to unmap_page()
  initramfs: clean old path before creating a hardlink
  kernel/kcov.c: mark funcs in __sanitizer_cov_trace_pc() as notrace
  psi: make disabling/enabling easier for vendor kernels
  proc: fixup map_files test on arm
  debugobjects: avoid recursive calls with kmemleak
  userfaultfd: shmem: UFFDIO_COPY: set the page dirty if VM_WRITE is not set
  ...
2018-12-04 09:38:05 -07:00
Rafael J. Wysocki
a72173ecfc Revert "exec: make de_thread() freezable"
Revert commit c22397888f "exec: make de_thread() freezable" as
requested by Ingo Molnar:

"So there's a new regression in v4.20-rc4, my desktop produces this
lockdep splat:

[ 1772.588771] WARNING: pkexec/4633 still has locks held!
[ 1772.588773] 4.20.0-rc4-custom-00213-g93a49841322b #1 Not tainted
[ 1772.588775] ------------------------------------
[ 1772.588776] 1 lock held by pkexec/4633:
[ 1772.588778]  #0: 00000000ed85fbf8 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x2a/0x70
[ 1772.588786] stack backtrace:
[ 1772.588789] CPU: 7 PID: 4633 Comm: pkexec Not tainted 4.20.0-rc4-custom-00213-g93a49841322b #1
[ 1772.588792] Call Trace:
[ 1772.588800]  dump_stack+0x85/0xcb
[ 1772.588803]  flush_old_exec+0x116/0x890
[ 1772.588807]  ? load_elf_phdrs+0x72/0xb0
[ 1772.588809]  load_elf_binary+0x291/0x1620
[ 1772.588815]  ? sched_clock+0x5/0x10
[ 1772.588817]  ? search_binary_handler+0x6d/0x240
[ 1772.588820]  search_binary_handler+0x80/0x240
[ 1772.588823]  load_script+0x201/0x220
[ 1772.588825]  search_binary_handler+0x80/0x240
[ 1772.588828]  __do_execve_file.isra.32+0x7d2/0xa60
[ 1772.588832]  ? strncpy_from_user+0x40/0x180
[ 1772.588835]  __x64_sys_execve+0x34/0x40
[ 1772.588838]  do_syscall_64+0x60/0x1c0

The warning gets triggered by an ancient lockdep check in the freezer:

(gdb) list *0xffffffff812ece06
0xffffffff812ece06 is in flush_old_exec (./include/linux/freezer.h:57).
52	 * DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION
53	 * If try_to_freeze causes a lockdep warning it means the caller may deadlock
54	 */
55	static inline bool try_to_freeze_unsafe(void)
56	{
57		might_sleep();
58		if (likely(!freezing(current)))
59			return false;
60		return __refrigerator(false);
61	}

I reviewed the ->cred_guard_mutex code, and the mutex is held across all
of exec() - and we always did this.

But there's this recent -rc4 commit:

> Chanho Min (1):
>       exec: make de_thread() freezable

  c22397888f: exec: make de_thread() freezable

I believe this commit is bogus, you cannot call try_to_freeze() from
de_thread(), because it's holding the ->cred_guard_mutex."

Reported-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-12-04 16:04:20 +01:00
Qu Wenruo
10950929e9 btrfs: tree-checker: Don't check max block group size as current max chunk size limit is unreliable
[BUG]
A completely valid btrfs will refuse to mount, with error message like:
  BTRFS critical (device sdb2): corrupt leaf: root=2 block=239681536 slot=172 \
    bg_start=12018974720 bg_len=10888413184, invalid block group size, \
    have 10888413184 expect (0, 10737418240]

This has been reported several times as the 4.19 kernel is now being
used. The filesystem refuses to mount, but is otherwise ok and booting
4.18 is a workaround.

Btrfs check returns no error, and all kernels used on this fs is later
than 2011, which should all have the 10G size limit commit.

[CAUSE]
For a 12 devices btrfs, we could allocate a chunk larger than 10G due to
stripe stripe bump up.

__btrfs_alloc_chunk()
|- max_stripe_size = 1G
|- max_chunk_size = 10G
|- data_stripe = 11
|- if (1G * 11 > 10G) {
       stripe_size = 976128930;
       stripe_size = round_up(976128930, SZ_16M) = 989855744

However the final stripe_size (989855744) * 11 = 10888413184, which is
still larger than 10G.

[FIX]
For the comprehensive check, we need to do the full check at chunk read
time, and rely on bg <-> chunk mapping to do the check.

We could just skip the length check for now.

Fixes: fce466eab7 ("btrfs: tree-checker: Verify block_group_item")
Cc: stable@vger.kernel.org # v4.19+
Reported-by: Wang Yugui <wangyugui@e16-tech.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-04 15:05:30 +01:00
Miklos Szeredi
ec7ba118b9 Revert "ovl: relax permission checking on underlying layers"
This reverts commit 007ea44892.

The commit broke some selinux-testsuite cases, and it looks like there's no
straightforward fix keeping the direction of this patch, so revert for now.

The original patch was trying to fix the consistency of permission checks, and
not an observed bug.  So reverting should be safe.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-12-04 11:31:30 +01:00
Ingo Molnar
4bbfd7467c Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU changes from Paul E. McKenney:

- Convert RCU's BUG_ON() and similar calls to WARN_ON() and similar.

- Replace calls of RCU-bh and RCU-sched update-side functions
  to their vanilla RCU counterparts.  This series is a step
  towards complete removal of the RCU-bh and RCU-sched update-side
  functions.

  ( Note that some of these conversions are going upstream via their
    respective maintainers. )

- Documentation updates, including a number of flavor-consolidation
  updates from Joel Fernandes.

- Miscellaneous fixes.

- Automate generation of the initrd filesystem used for
  rcutorture testing.

- Convert spin_is_locked() assertions to instead use lockdep.

  ( Note that some of these conversions are going upstream via their
    respective maintainers. )

- SRCU updates, especially including a fix from Dennis Krein
  for a bag-on-head-class bug.

- RCU torture-test updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-04 07:52:30 +01:00
ruippan (潘睿)
e647e29196 ext4: fix EXT4_IOC_GROUP_ADD ioctl
Commit e2b911c535 ("ext4: clean up feature test macros with
predicate functions") broke the EXT4_IOC_GROUP_ADD ioctl.  This was
not noticed since only very old versions of resize2fs (before
e2fsprogs 1.42) use this ioctl.  However, using a new kernel with an
enterprise Linux userspace will cause attempts to use online resize to
fail with "No reserved GDT blocks".

Fixes: e2b911c535 ("ext4: clean up feature test macros with predicate...")
Cc: stable@kernel.org # v4.4
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: ruippan (潘睿) <ruippan@tencent.com>
2018-12-04 01:04:12 -05:00
Eric Sandeen
361d24d406 ext4: hard fail dax mount on unsupported devices
As dax inches closer to production use, an administrator should not
be surprised by silently disabling the feature they asked for.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-12-04 00:46:39 -05:00
Chengguang Xu
50c15df69e ext4: remove redundant condition check
ext4_xattr_destroy_cache() can handle NULL pointer correctly,
so there is no need to check NULL pointer before calling
ext4_xattr_destroy_cache().

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-12-04 00:24:42 -05:00
Colin Ian King
561405f031 jbd2: clean up indentation issue, replace spaces with tab
There is a statement that is indented with spaces, replace it with
a tab.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-12-04 00:20:10 -05:00
Colin Ian King
a92abd738d ext4: clean up indentation issues, remove extraneous tabs
There are several lines that are indented too far, clean these
up by removing the tabs.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-12-04 00:16:44 -05:00
Maurizio Lombardi
132d00becb ext4: missing unlock/put_page() in ext4_try_to_write_inline_data()
In case of error, ext4_try_to_write_inline_data() should unlock
and release the page it holds.

Fixes: f19d5870cb ("ext4: add normal write support for inline data")
Cc: stable@kernel.org # 3.8
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-12-04 00:06:53 -05:00
Pan Bian
61157b24e6 ext4: fix possible use after free in ext4_quota_enable
The function frees qf_inode via iput but then pass qf_inode to
lockdep_set_quota_inode on the failure path. This may result in a
use-after-free bug. The patch frees df_inode only when it is never used.

Fixes: daf647d2dd ("ext4: add lockdep annotations for i_data_sem")
Cc: stable@kernel.org # 4.6
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-12-03 23:28:02 -05:00
Jan Kara
96f1e09745 jbd2: avoid long hold times of j_state_lock while committing a transaction
We can hold j_state_lock for writing at the beginning of
jbd2_journal_commit_transaction() for a rather long time (reportedly for
30 ms) due cleaning revoke bits of all revoked buffers under it. The
handling of revoke tables as well as cleaning of t_reserved_list, and
checkpoint lists does not need j_state_lock for anything. It is only
needed to prevent new handles from joining the transaction. Generally
T_LOCKED transaction state prevents new handles from joining the
transaction - except for reserved handles which have to allowed to join
while we wait for other handles to complete.

To prevent reserved handles from joining the transaction while cleaning
up lists, add new transaction state T_SWITCH and watch for it when
starting reserved handles. With this we can just drop the lock for
operations that don't need it.

Reported-and-tested-by: Adrian Hunter <adrian.hunter@intel.com>
Suggested-by: "Theodore Y. Ts'o" <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-12-03 23:16:07 -05:00
Kees Cook
8665569e97 pstore/ram: Avoid NULL deref in ftrace merging failure path
Given corruption in the ftrace records, it might be possible to allocate
tmp_prz without assigning prz to it, but still marking it as needing to
be freed, which would cause at least a NULL dereference.

smatch warnings:
fs/pstore/ram.c:340 ramoops_pstore_read() error: we previously assumed 'prz' could be null (see line 255)

https://lists.01.org/pipermail/kbuild-all/2018-December/055528.html

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 2fbea82bbb ("pstore: Merge per-CPU ftrace records into one")
Cc: "Joel Fernandes (Google)" <joel@joelfernandes.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03 17:11:02 -08:00
Kees Cook
ea84b580b9 pstore: Convert buf_lock to semaphore
Instead of running with interrupts disabled, use a semaphore. This should
make it easier for backends that may need to sleep (e.g. EFI) when
performing a write:

|BUG: sleeping function called from invalid context at kernel/sched/completion.c:99
|in_atomic(): 1, irqs_disabled(): 1, pid: 2236, name: sig-xstate-bum
|Preemption disabled at:
|[<ffffffff99d60512>] pstore_dump+0x72/0x330
|CPU: 26 PID: 2236 Comm: sig-xstate-bum Tainted: G      D           4.20.0-rc3 #45
|Call Trace:
| dump_stack+0x4f/0x6a
| ___might_sleep.cold.91+0xd3/0xe4
| __might_sleep+0x50/0x90
| wait_for_completion+0x32/0x130
| virt_efi_query_variable_info+0x14e/0x160
| efi_query_variable_store+0x51/0x1a0
| efivar_entry_set_safe+0xa3/0x1b0
| efi_pstore_write+0x109/0x140
| pstore_dump+0x11c/0x330
| kmsg_dump+0xa4/0xd0
| oops_exit+0x22/0x30
...

Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Fixes: 21b3ddd39f ("efi: Don't use spinlocks for efi vars")
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03 17:11:02 -08:00
Thomas Meyer
69596433bc pstore: Fix bool initialization/comparison
Bool initializations should use true and false. Bool tests don't need
comparisons.

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03 16:52:35 -08:00
Joel Fernandes (Google)
30696378f6 pstore/ram: Do not treat empty buffers as valid
The ramoops backend currently calls persistent_ram_save_old() even
if a buffer is empty. While this appears to work, it is does not seem
like the right thing to do and could lead to future bugs so lets avoid
that. It also prevents misleading prints in the logs which claim the
buffer is valid.

I got something like:

	found existing buffer, size 0, start 0

When I was expecting:

	no valid data in buffer (sig = ...)

This bails out early (and reports with pr_debug()), since it's an
acceptable state.

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03 16:52:35 -08:00