Commit Graph

41275 Commits

Author SHA1 Message Date
Linus Torvalds
c83727a656 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS fixes from Al Viro:
 "Fixes for this cycle regression in overlayfs and a couple of
  long-standing (== all the way back to 2.6.12, at least) bugs"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  freeing unlinked file indefinitely delayed
  fix a braino in ovl_d_select_inode()
  9p: don't leave a half-initialized inode sitting around
2015-07-12 14:09:36 -07:00
Al Viro
75a6f82a0d freeing unlinked file indefinitely delayed
Normally opening a file, unlinking it and then closing will have
the inode freed upon close() (provided that it's not otherwise busy and
has no remaining links, of course).  However, there's one case where that
does *not* happen.  Namely, if you open it by fhandle with cold dcache,
then unlink() and close().

	In normal case you get d_delete() in unlink(2) notice that dentry
is busy and unhash it; on the final dput() it will be forcibly evicted from
dcache, triggering iput() and inode removal.  In this case, though, we end
up with *two* dentries - disconnected (created by open-by-fhandle) and
regular one (used by unlink()).  The latter will have its reference to inode
dropped just fine, but the former will not - it's considered hashed (it
is on the ->s_anon list), so it will stay around until the memory pressure
will finally do it in.  As the result, we have the final iput() delayed
indefinitely.  It's trivial to reproduce -

void flush_dcache(void)
{
        system("mount -o remount,rw /");
}

static char buf[20 * 1024 * 1024];

main()
{
        int fd;
        union {
                struct file_handle f;
                char buf[MAX_HANDLE_SZ];
        } x;
        int m;

        x.f.handle_bytes = sizeof(x);
        chdir("/root");
        mkdir("foo", 0700);
        fd = open("foo/bar", O_CREAT | O_RDWR, 0600);
        close(fd);
        name_to_handle_at(AT_FDCWD, "foo/bar", &x.f, &m, 0);
        flush_dcache();
        fd = open_by_handle_at(AT_FDCWD, &x.f, O_RDWR);
        unlink("foo/bar");
        write(fd, buf, sizeof(buf));
        system("df .");			/* 20Mb eaten */
        close(fd);
        system("df .");			/* should've freed those 20Mb */
        flush_dcache();
        system("df .");			/* should be the same as #2 */
}

will spit out something like
Filesystem     1K-blocks   Used Available Use% Mounted on
/dev/root         322023 303843      1131 100% /
Filesystem     1K-blocks   Used Available Use% Mounted on
/dev/root         322023 303843      1131 100% /
Filesystem     1K-blocks   Used Available Use% Mounted on
/dev/root         322023 283282     21692  93% /
- inode gets freed only when dentry is finally evicted (here we trigger
than by remount; normally it would've happened in response to memory
pressure hell knows when).

Cc: stable@vger.kernel.org # v2.6.38+; earlier ones need s/kill_it/unhash_it/
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-07-12 11:27:04 -04:00
Al Viro
9391dd00d1 fix a braino in ovl_d_select_inode()
when opening a directory we want the overlayfs inode, not one from
the topmost layer.

Reported-By: Andrey Jr. Melnikov <temnota.am@gmail.com>
Tested-By: Andrey Jr. Melnikov <temnota.am@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-07-12 11:22:05 -04:00
Al Viro
0a73d0a204 9p: don't leave a half-initialized inode sitting around
Cc: stable@vger.kernel.org # all branches
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-07-12 11:22:05 -04:00
Linus Torvalds
31b7a57c9e Merge branch 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "This is an assortment of fixes.  Most of the commits are from Filipe
  (fsync, the inode allocation cache and a few others).  Mark kicked in
  a series fixing corners in the extent sharing ioctls, and everyone
  else fixed up on assorted other problems"

* 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix wrong check for btrfs_force_chunk_alloc()
  Btrfs: fix warning of bytes_may_use
  Btrfs: fix hang when failing to submit bio of directIO
  Btrfs: fix a comment in inode.c:evict_inode_truncate_pages()
  Btrfs: fix memory corruption on failure to submit bio for direct IO
  btrfs: don't update mtime/ctime on deduped inodes
  btrfs: allow dedupe of same inode
  btrfs: fix deadlock with extent-same and readpage
  btrfs: pass unaligned length to btrfs_cmp_data()
  Btrfs: fix fsync after truncate when no_holes feature is enabled
  Btrfs: fix fsync xattr loss in the fast fsync path
  Btrfs: fix fsync data loss after append write
  Btrfs: fix crash on close_ctree() if cleaner starts new transaction
  Btrfs: fix race between caching kthread and returning inode to inode cache
  Btrfs: use kmem_cache_free when freeing entry in inode cache
  Btrfs: fix race between balance and unused block group deletion
  btrfs: add error handling for scrub_workers_get()
  btrfs: cleanup noused initialization of dev in btrfs_end_bio()
  btrfs: qgroup: allow user to clear the limitation on qgroup
2015-07-11 10:26:34 -07:00
Joe Perches
a28e4b2b18 hpfs: hpfs_error: Remove static buffer, use vsprintf extension %pV instead
Removing unnecessary static buffers is good.
Use the vsprintf %pV extension instead.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Mikulas Patocka <mikulas@twibright.com>
Cc: stable@vger.kernel.org      # v2.6.36+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-09 13:35:31 -07:00
Sanidhya Kashyap
ce657611ba hpfs: kstrdup() out of memory handling
There is a possibility of nothing being allocated to the new_opts in
case of memory pressure, therefore return ENOMEM for such case.

Signed-off-by: Sanidhya Kashyap <sanidhya.gatech@gmail.com>
Signed-off-by: Mikulas Patocka <mikulas@twibright.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-09 13:35:31 -07:00
Firo Yang
d7b04097c2 hpfs: Remove unessary cast
Avoid a pointless kmem_cache_alloc() return value cast in
fs/hpfs/super.c::hpfs_alloc_inode()

Signed-off-by: Firo Yang <firogm@gmail.com>
Signed-off-by: Mikulas Patocka <mikulas@twibright.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-09 13:35:31 -07:00
Mikulas Patocka
a27b5b97d6 hpfs: add fstrim support
This patch adds support for fstrim to the HPFS filesystem.

Signed-off-by: Mikulas Patocka <mikulas@twibright.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-09 13:35:30 -07:00
Mikulas Patocka
9abea2d64c ioctl_compat: handle FITRIM
The FITRIM ioctl has the same arguments on 32-bit and 64-bit
architectures, so we can add it to the list of compatible ioctls and
drop it from compat_ioctl method of various filesystems.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ted Ts'o <tytso@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-09 11:42:21 -07:00
Linus Torvalds
1c4c7159ed Bug fixes (all for stable kernels) for ext4:
* address corner cases for indirect blocks->extent migration
   * fix reserved block accounting invalidate_page when
 	page_size != block_size (i.e., ppc or 1k block size file systems)
   * fix deadlocks when a memcg is under heavy memory pressure
   * fix fencepost error in lazytime optimization
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 bugfixes from Ted Ts'o:
 "Bug fixes (all for stable kernels) for ext4:

   - address corner cases for indirect blocks->extent migration

   - fix reserved block accounting invalidate_page when
     page_size != block_size (i.e., ppc or 1k block size file systems)

   - fix deadlocks when a memcg is under heavy memory pressure

   - fix fencepost error in lazytime optimization"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: replace open coded nofail allocation in ext4_free_blocks()
  ext4: correctly migrate a file with a hole at the beginning
  ext4: be more strict when migrating to non-extent based file
  ext4: fix reservation release on invalidatepage for delalloc fs
  ext4: avoid deadlocks in the writeback path by using sb_getblk_gfp
  bufferhead: Add _gfp version for sb_getblk()
  ext4: fix fencepost error in lazytime optimization
2015-07-05 16:24:54 -07:00
Michal Hocko
7444a072c3 ext4: replace open coded nofail allocation in ext4_free_blocks()
ext4_free_blocks is looping around the allocation request and mimics
__GFP_NOFAIL behavior without any allocation fallback strategy. Let's
remove the open coded loop and replace it with __GFP_NOFAIL. Without the
flag the allocator has no way to find out never-fail requirement and
cannot help in any way.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2015-07-05 12:33:44 -04:00
Linus Torvalds
1dc51b8288 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro:
 "Assorted VFS fixes and related cleanups (IMO the most interesting in
  that part are f_path-related things and Eric's descriptor-related
  stuff).  UFS regression fixes (it got broken last cycle).  9P fixes.
  fs-cache series, DAX patches, Jan's file_remove_suid() work"

[ I'd say this is much more than "fixes and related cleanups".  The
  file_table locking rule change by Eric Dumazet is a rather big and
  fundamental update even if the patch isn't huge.   - Linus ]

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits)
  9p: cope with bogus responses from server in p9_client_{read,write}
  p9_client_write(): avoid double p9_free_req()
  9p: forgetting to cancel request on interrupted zero-copy RPC
  dax: bdev_direct_access() may sleep
  block: Add support for DAX reads/writes to block devices
  dax: Use copy_from_iter_nocache
  dax: Add block size note to documentation
  fs/file.c: __fget() and dup2() atomicity rules
  fs/file.c: don't acquire files->file_lock in fd_install()
  fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
  vfs: avoid creation of inode number 0 in get_next_ino
  namei: make set_root_rcu() return void
  make simple_positive() public
  ufs: use dir_pages instead of ufs_dir_pages()
  pagemap.h: move dir_pages() over there
  remove the pointless include of lglock.h
  fs: cleanup slight list_entry abuse
  xfs: Correctly lock inode when removing suid and file capabilities
  fs: Call security_ops->inode_killpriv on truncate
  fs: Provide function telling whether file_remove_privs() will do anything
  ...
2015-07-04 19:36:06 -07:00
Matthew Wilcox
43c3dd08da dax: bdev_direct_access() may sleep
The brd driver is the only in-tree driver that may sleep currently.
After some discussion on linux-fsdevel, we decided that any driver
may choose to sleep in its ->direct_access method.  To ensure that all
callers of bdev_direct_access() are prepared for this, add a call
to might_sleep().

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-07-04 15:56:57 -04:00
Matthew Wilcox
bbab37ddc2 block: Add support for DAX reads/writes to block devices
If a block device supports the ->direct_access methods, bypass the normal
DIO path and use DAX to go straight to memcpy() instead of allocating
a DIO and a BIO.

Includes support for the DIO_SKIP_DIO_COUNT flag in DAX, as is done in
do_blockdev_direct_IO().

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-07-04 15:56:57 -04:00
Matthew Wilcox
872eb127e3 dax: Use copy_from_iter_nocache
When userspace does a write, there's no need for the written data to
pollute the CPU cache.  This matches the original XIP code.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-07-04 15:56:56 -04:00
Linus Torvalds
22a093b2fb Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Debug info and other statistics fixes and related enhancements"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/numa: Fix numa balancing stats in /proc/pid/sched
  sched/numa: Show numa_group ID in /proc/sched_debug task listings
  sched/debug: Move print_cfs_rq() declaration to kernel/sched/sched.h
  sched/stat: Expose /proc/pid/schedstat if CONFIG_SCHED_INFO=y
  sched/stat: Simplify the sched_info accounting dependency
2015-07-04 08:56:53 -07:00
Naveen N. Rao
5968cecedd sched/stat: Expose /proc/pid/schedstat if CONFIG_SCHED_INFO=y
Expand /proc/pid/schedstat output:

 - enable it on CONFIG_TASK_DELAY_ACCT=y && !CONFIG_SCHEDSTATS kernels.

 - dump all zeroes on kernels that are booted with the 'nodelayacct'
   option, which boot option disables delay accounting on
   CONFIG_TASK_DELAY_ACCT=y kernels.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: a.p.zijlstra@chello.nl
Cc: ricklind@us.ibm.com
Link: http://lkml.kernel.org/r/5ccbef17d4bc841084ea6e6421d4e4a23b7b806f.1435654789.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-04 10:04:31 +02:00
Eryu Guan
8974fec7d7 ext4: correctly migrate a file with a hole at the beginning
Currently ext4_ind_migrate() doesn't correctly handle a file which
contains a hole at the beginning of the file.  This caused the migration
to be done incorrectly, and then if there is a subsequent following
delayed allocation write to the "hole", this would reclaim the same data
blocks again and results in fs corruption.

  # assmuing 4k block size ext4, with delalloc enabled
  # skip the first block and write to the second block
  xfs_io -fc "pwrite 4k 4k" -c "fsync" /mnt/ext4/testfile

  # converting to indirect-mapped file, which would move the data blocks
  # to the beginning of the file, but extent status cache still marks
  # that region as a hole
  chattr -e /mnt/ext4/testfile

  # delayed allocation writes to the "hole", reclaim the same data block
  # again, results in i_blocks corruption
  xfs_io -c "pwrite 0 4k" /mnt/ext4/testfile
  umount /mnt/ext4
  e2fsck -nf /dev/sda6
  ...
  Inode 53, i_blocks is 16, should be 8.  Fix? no
  ...

Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2015-07-04 00:03:44 -04:00
Eryu Guan
d6f123a929 ext4: be more strict when migrating to non-extent based file
Currently the check in ext4_ind_migrate() is not enough before doing the
real conversion:

a) delayed allocated extents could bypass the check on eh->eh_entries
   and eh->eh_depth

This can be demonstrated by this script

  xfs_io -fc "pwrite 0 4k" -c "pwrite 8k 4k" /mnt/ext4/testfile
  chattr -e /mnt/ext4/testfile

where testfile has two extents but still be converted to non-extent
based file format.

b) only extent length is checked but not the offset, which would result
   in data lose (delalloc) or fs corruption (nodelalloc), because
   non-extent based file only supports at most (12 + 2^10 + 2^20 + 2^30)
   blocks

This can be demostrated by

  xfs_io -fc "pwrite 5T 4k" /mnt/ext4/testfile
  chattr -e /mnt/ext4/testfile
  sync

If delalloc is enabled, dmesg prints
  EXT4-fs warning (device dm-4): ext4_block_to_path:105: block 1342177280 > max in inode 53
  EXT4-fs (dm-4): Delayed block allocation failed for inode 53 at logical offset 1342177280 with max blocks 1 with error 5
  EXT4-fs (dm-4): This should not happen!! Data will be lost

If delalloc is disabled, e2fsck -nf shows corruption
  Inode 53, i_size is 5497558142976, should be 4096.  Fix? no

Fix the two issues by

a) forcing all delayed allocation blocks to be allocated before checking
   eh->eh_depth and eh->eh_entries
b) limiting the last logical block of the extent is within direct map

Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2015-07-03 23:56:50 -04:00
Lukas Czerner
9705acd63b ext4: fix reservation release on invalidatepage for delalloc fs
On delalloc enabled file system on invalidatepage operation
in ext4_da_page_release_reservation() we want to clear the delayed
buffer and remove the extent covering the delayed buffer from the extent
status tree.

However currently there is a bug where on the systems with page size >
block size we will always remove extents from the start of the page
regardless where the actual delayed buffers are positioned in the page.
This leads to the errors like this:

EXT4-fs warning (device loop0): ext4_da_release_space:1225:
ext4_da_release_space: ino 13, to_free 1 with only 0 reserved data
blocks

This however can cause data loss on writeback time if the file system is
in ENOSPC condition because we're releasing reservation for someones
else delayed buffer.

Fix this by only removing extents that corresponds to the part of the
page we want to invalidate.

This problem is reproducible by the following fio receipt (however I was
only able to reproduce it with fio-2.1 or older.

[global]
bs=8k
iodepth=1024
iodepth_batch=60
randrepeat=1
size=1m
directory=/mnt/test
numjobs=20
[job1]
ioengine=sync
bs=1k
direct=1
rw=randread
filename=file1:file2
[job2]
ioengine=libaio
rw=randwrite
direct=1
filename=file1:file2
[job3]
bs=1k
ioengine=posixaio
rw=randwrite
direct=1
filename=file1:file2
[job5]
bs=1k
ioengine=sync
rw=randread
filename=file1:file2
[job7]
ioengine=libaio
rw=randwrite
filename=file1:file2
[job8]
ioengine=posixaio
rw=randwrite
filename=file1:file2
[job10]
ioengine=mmap
rw=randwrite
bs=1k
filename=file1:file2
[job11]
ioengine=mmap
rw=randwrite
direct=1
filename=file1:file2

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
2015-07-03 21:13:55 -04:00
Linus Torvalds
0cbee99269 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace updates from Eric Biederman:
 "Long ago and far away when user namespaces where young it was realized
  that allowing fresh mounts of proc and sysfs with only user namespace
  permissions could violate the basic rule that only root gets to decide
  if proc or sysfs should be mounted at all.

  Some hacks were put in place to reduce the worst of the damage could
  be done, and the common sense rule was adopted that fresh mounts of
  proc and sysfs should allow no more than bind mounts of proc and
  sysfs.  Unfortunately that rule has not been fully enforced.

  There are two kinds of gaps in that enforcement.  Only filesystems
  mounted on empty directories of proc and sysfs should be ignored but
  the test for empty directories was insufficient.  So in my tree
  directories on proc, sysctl and sysfs that will always be empty are
  created specially.  Every other technique is imperfect as an ordinary
  directory can have entries added even after a readdir returns and
  shows that the directory is empty.  Special creation of directories
  for mount points makes the code in the kernel a smidge clearer about
  it's purpose.  I asked container developers from the various container
  projects to help test this and no holes were found in the set of mount
  points on proc and sysfs that are created specially.

  This set of changes also starts enforcing the mount flags of fresh
  mounts of proc and sysfs are consistent with the existing mount of
  proc and sysfs.  I expected this to be the boring part of the work but
  unfortunately unprivileged userspace winds up mounting fresh copies of
  proc and sysfs with noexec and nosuid clear when root set those flags
  on the previous mount of proc and sysfs.  So for now only the atime,
  read-only and nodev attributes which userspace happens to keep
  consistent are enforced.  Dealing with the noexec and nosuid
  attributes remains for another time.

  This set of changes also addresses an issue with how open file
  descriptors from /proc/<pid>/ns/* are displayed.  Recently readlink of
  /proc/<pid>/fd has been triggering a WARN_ON that has not been
  meaningful since it was added (as all of the code in the kernel was
  converted) and is not now actively wrong.

  There is also a short list of issues that have not been fixed yet that
  I will mention briefly.

  It is possible to rename a directory from below to above a bind mount.
  At which point any directory pointers below the renamed directory can
  be walked up to the root directory of the filesystem.  With user
  namespaces enabled a bind mount of the bind mount can be created
  allowing the user to pick a directory whose children they can rename
  to outside of the bind mount.  This is challenging to fix and doubly
  so because all obvious solutions must touch code that is in the
  performance part of pathname resolution.

  As mentioned above there is also a question of how to ensure that
  developers by accident or with purpose do not introduce exectuable
  files on sysfs and proc and in doing so introduce security regressions
  in the current userspace that will not be immediately obvious and as
  such are likely to require breaking userspace in painful ways once
  they are recognized"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  vfs: Remove incorrect debugging WARN in prepend_path
  mnt: Update fs_fully_visible to test for permanently empty directories
  sysfs: Create mountpoints with sysfs_create_mount_point
  sysfs: Add support for permanently empty directories to serve as mount points.
  kernfs: Add support for always empty directories.
  proc: Allow creating permanently empty directories that serve as mount points
  sysctl: Allow creating permanently empty directories that serve as mountpoints.
  fs: Add helper functions for permanently empty directories.
  vfs: Ignore unlocked mounts in fs_fully_visible
  mnt: Modify fs_fully_visible to deal with locked ro nodev and atime
  mnt: Refactor the logic for mounting sysfs and proc in a user namespace
2015-07-03 15:20:57 -07:00
Linus Torvalds
0c76c6ba24 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull Ceph updates from Sage Weil:
 "We have a pile of bug fixes from Ilya, including a few patches that
  sync up the CRUSH code with the latest from userspace.

  There is also a long series from Zheng that fixes various issues with
  snapshots, inline data, and directory fsync, some simplification and
  improvement in the cap release code, and a rework of the caching of
  directory contents.

  To top it off there are a few small fixes and cleanups from Benoit and
  Hong"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (40 commits)
  rbd: use GFP_NOIO in rbd_obj_request_create()
  crush: fix a bug in tree bucket decode
  libceph: Fix ceph_tcp_sendpage()'s more boolean usage
  libceph: Remove spurious kunmap() of the zero page
  rbd: queue_depth map option
  rbd: store rbd_options in rbd_device
  rbd: terminate rbd_opts_tokens with Opt_err
  ceph: fix ceph_writepages_start()
  rbd: bump queue_max_segments
  ceph: rework dcache readdir
  crush: sync up with userspace
  crush: fix crash from invalid 'take' argument
  ceph: switch some GFP_NOFS memory allocation to GFP_KERNEL
  ceph: pre-allocate data structure that tracks caps flushing
  ceph: re-send flushing caps (which are revoked) in reconnect stage
  ceph: send TID of the oldest pending caps flush to MDS
  ceph: track pending caps flushing globally
  ceph: track pending caps flushing accurately
  libceph: fix wrong name "Ceph filesystem for Linux"
  ceph: fix directory fsync
  ...
2015-07-02 11:35:00 -07:00
Linus Torvalds
8688d9540c NFS client updates for Linux 4.2
Highlights include:
 
 Stable patches:
 - Fix a crash in the NFSv4 file locking code.
 - Fix an fsync() regression, where we were failing to retry I/O in some
   circumstances.
 - Fix an infinite loop in NFSv4.0 OPEN stateid recovery
 - Fix a memory leak when an attempted pnfs fails.
 - Fix a memory leak in the backchannel code
 - Large hostnames were not supported correctly in NFSv4.1
 - Fix a pNFS/flexfiles bug that was impeding error reporting on I/O.
 - Fix a couple of credential issues in pNFS/flexfiles
 
 Bugfixes + cleanups:
 - Open flag sanity checks in the NFSv4 atomic open codepath
 - More NFSv4 delegation related bugfixes
 - Various NFSv4.1 backchannel bugfixes and cleanups
 - Fix the NFS swap socket code
 - Various cleanups of the NFSv4 SETCLIENTID and EXCHANGE_ID code
 - Fix a UDP transport deadlock issue
 
 Features:
 - More RDMA client transport improvements
 - NFSv4.2 LAYOUTSTATS functionality for pnfs flexfiles.
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Merge tag 'nfs-for-4.2-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  Stable patches:
   - Fix a crash in the NFSv4 file locking code.
   - Fix an fsync() regression, where we were failing to retry I/O in
     some circumstances.
   - Fix an infinite loop in NFSv4.0 OPEN stateid recovery
   - Fix a memory leak when an attempted pnfs fails.
   - Fix a memory leak in the backchannel code
   - Large hostnames were not supported correctly in NFSv4.1
   - Fix a pNFS/flexfiles bug that was impeding error reporting on I/O.
   - Fix a couple of credential issues in pNFS/flexfiles

  Bugfixes + cleanups:
   - Open flag sanity checks in the NFSv4 atomic open codepath
   - More NFSv4 delegation related bugfixes
   - Various NFSv4.1 backchannel bugfixes and cleanups
   - Fix the NFS swap socket code
   - Various cleanups of the NFSv4 SETCLIENTID and EXCHANGE_ID code
   - Fix a UDP transport deadlock issue

  Features:
   - More RDMA client transport improvements
   - NFSv4.2 LAYOUTSTATS functionality for pnfs flexfiles"

* tag 'nfs-for-4.2-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (87 commits)
  nfs: Remove invalid tk_pid from debug message
  nfs: Remove invalid NFS_ATTR_FATTR_V4_REFERRAL checking in nfs4_get_rootfh
  nfs: Drop bad comment in nfs41_walk_client_list()
  nfs: Remove unneeded micro checking of CONFIG_PROC_FS
  nfs: Don't setting FILE_CREATED flags always
  nfs: Use remove_proc_subtree() instead remove_proc_entry()
  nfs: Remove unused argument in nfs_server_set_fsinfo()
  nfs: Fix a memory leak when meeting an unsupported state protect
  nfs: take extra reference to fl->fl_file when running a LOCKU operation
  NFSv4: When returning a delegation, don't reclaim an incompatible open mode.
  NFSv4.2: LAYOUTSTATS is optional to implement
  NFSv4.2: Fix up a decoding error in layoutstats
  pNFS/flexfiles: Fix the reset of struct pgio_header when resending
  pNFS/flexfiles: Turn off layoutcommit for servers that don't need it
  pnfs/flexfiles: protect ktime manipulation with mirror lock
  nfs: provide pnfs_report_layoutstat when NFS42 is disabled
  nfs: verify open flags before allowing open
  nfs: always update creds in mirror, even when we have an already connected ds
  nfs: fix potential credential leak in ff_layout_update_mirror_cred
  pnfs/flexfiles: report layoutstat regularly
  ...
2015-07-02 11:32:23 -07:00
Linus Torvalds
320cd413fa Merge branch 'overlayfs-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs updates from Miklos Szeredi:
 "This relaxes the requirements on the lower layer filesystem: now ones
  that implement .d_revalidate, such as NFS, can be used.

  Upper layer filesystems still has the "no .d_revalidate" requirement.

  Also a bad interaction with jffs2 locking has been fixed"

* 'overlayfs-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: lookup whiteouts outside iterate_dir()
  ovl: allow distributed fs as lower layer
  ovl: don't traverse automount points
2015-07-02 11:23:00 -07:00
Linus Torvalds
a7ba4bf5e7 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse updates from Miklos Szeredi:
 "This is the start of improving fuse scalability.

  An input queue and a processing queue is split out from the monolithic
  fuse connection, each of those having their own spinlock.  The end of
  the patchset adds the ability to clone a fuse connection.  This means,
  that instead of having to read/write requests/answers on a single fuse
  device fd, the fuse daemon can have multiple distinct file descriptors
  open.  Each of those can be used to receive requests and send answers,
  currently the only constraint is that a request must be answered on
  the same fd as it was read from.

  This can be extended further to allow binding a device clone to a
  specific CPU or NUMA node.

  Based on a patchset by Srinivas Eeda and Ashish Samant.  Thanks to
  Ashish for the review of this series"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (40 commits)
  fuse: update MAINTAINERS entry
  fuse: separate pqueue for clones
  fuse: introduce per-instance fuse_dev structure
  fuse: device fd clone
  fuse: abort: no fc->lock needed for request ending
  fuse: no fc->lock for pqueue parts
  fuse: no fc->lock in request_end()
  fuse: cleanup request_end()
  fuse: request_end(): do once
  fuse: add req flag for private list
  fuse: pqueue locking
  fuse: abort: group pqueue accesses
  fuse: cleanup fuse_dev_do_read()
  fuse: move list_del_init() from request_end() into callers
  fuse: duplicate ->connected in pqueue
  fuse: separate out processing queue
  fuse: simplify request_wait()
  fuse: no fc->lock for iqueue parts
  fuse: allow interrupt queuing without fc->lock
  fuse: iqueue locking
  ...
2015-07-02 11:21:26 -07:00
Linus Torvalds
9d90f03531 Replace module_init with appropriate alternate initcall in non modules.
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Merge tag 'module_init-alternate_initcall-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

Pull module_init replacement part two from Paul Gortmaker:
 "Replace module_init with appropriate alternate initcall in non
  modules.

  This series converts non-modular code that is using the module_init()
  call to hook itself into the system to instead use one of our
  alternate priority initcalls.

  Unlike the previous series that used device_initcall and hence was a
  runtime no-op, these commits change to one of the alternate initcalls,
  because (a) we have them and (b) it seems like the right thing to do.

  For example, it would seem logical to use arch_initcall for arch
  specific setup code and fs_initcall for filesystem setup code.

  This does mean however, that changes in the init ordering will be
  taking place, and so there is a small risk that some kind of implicit
  init ordering issue may lie uncovered.  But I think it is still better
  to give these ones sensible priorities than to just assign them all to
  device_initcall in order to exactly preserve the old ordering.

  Thad said, we have already made similar changes in core kernel code in
  commit c96d6660dc ("kernel: audit/fix non-modular users of
  module_init in core code") without any regressions reported, so this
  type of change isn't without precedent.  It has also got the same
  local testing and linux-next coverage as all the other pull requests
  that I'm sending for this merge window have got.

  Once again, there is an unused module_exit function removal that shows
  up as an outlier upon casual inspection of the diffstat"

* tag 'module_init-alternate_initcall-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  x86: perf_event_intel_pt.c: use arch_initcall to hook in enabling
  x86: perf_event_intel_bts.c: use arch_initcall to hook in enabling
  mm/page_owner.c: use late_initcall to hook in enabling
  lib/list_sort: use late_initcall to hook in self tests
  arm: use subsys_initcall in non-modular pl320 IPC code
  powerpc: don't use module_init for non-modular core hugetlb code
  powerpc: use subsys_initcall for Freescale Local Bus
  x86: don't use module_init for non-modular core bootflag code
  netfilter: don't use module_init/exit in core IPV4 code
  fs/notify: don't use module_init for non-modular inotify_user code
  mm: replace module_init usages with subsys_initcall in nommu.c
2015-07-02 10:36:29 -07:00
Nikolay Borisov
c45653c341 ext4: avoid deadlocks in the writeback path by using sb_getblk_gfp
Switch ext4 to using sb_getblk_gfp with GFP_NOFS added to fix possible
deadlocks in the page writeback path.

Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2015-07-02 01:34:07 -04:00
Theodore Ts'o
0f0ff9a9f3 ext4: fix fencepost error in lazytime optimization
Commit 8f4d855839: "ext4: fix lazytime optimization" was not a
complete fix.  In the case where the inode number is a multiple of 16,
and we could still end up updating an inode with dirty timestamps
written to the wrong inode on disk.  Oops.

This can be easily reproduced by using generic/005 with a file system
with metadata_csum and lazytime enabled.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2015-07-01 23:37:46 -04:00
Linus Torvalds
2d01eedf1d Merge branch 'akpm' (patches from Andrew)
Merge third patchbomb from Andrew Morton:

 - the rest of MM

 - scripts/gdb updates

 - ipc/ updates

 - lib/ updates

 - MAINTAINERS updates

 - various other misc things

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (67 commits)
  genalloc: rename of_get_named_gen_pool() to of_gen_pool_get()
  genalloc: rename dev_get_gen_pool() to gen_pool_get()
  x86: opt into HAVE_COPY_THREAD_TLS, for both 32-bit and 64-bit
  MAINTAINERS: add zpool
  MAINTAINERS: BCACHE: Kent Overstreet has changed email address
  MAINTAINERS: move Jens Osterkamp to CREDITS
  MAINTAINERS: remove unused nbd.h pattern
  MAINTAINERS: update brcm gpio filename pattern
  MAINTAINERS: update brcm dts pattern
  MAINTAINERS: update sound soc intel patterns
  MAINTAINERS: remove website for paride
  MAINTAINERS: update Emulex ocrdma email addresses
  bcache: use kvfree() in various places
  libcxgbi: use kvfree() in cxgbi_free_big_mem()
  target: use kvfree() in session alloc and free
  IB/ehca: use kvfree() in ipz_queue_{cd}tor()
  drm/nouveau/gem: use kvfree() in u_free()
  drm: use kvfree() in drm_free_large()
  cxgb4: use kvfree() in t4_free_mem()
  cxgb3: use kvfree() in cxgb_free_mem()
  ...
2015-07-01 17:47:51 -07:00
Shilong Wang
9689457b5b Btrfs: fix wrong check for btrfs_force_chunk_alloc()
btrfs_force_chunk_alloc() return 1 for allocation chunk successfully.
This problem exists since commit c87f08ca4.

With this patch, we might fix some enospc problems for balances.

Signed-off-by: Wang Shilong <wangshilong1991@gmail.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:22 -07:00
Liu Bo
ddba1bfc23 Btrfs: fix warning of bytes_may_use
While running generic/019, dmesg got several warnings from
btrfs_free_reserved_data_space().

Test generic/019 produces some disk failures so sumbit dio will get errors,
in which case, btrfs_direct_IO() goes to the error handling and free
bytes_may_use, but the problem is that bytes_may_use has been free'd
during get_block().

This adds a runtime flag to show if we've gone through get_block(), if so,
don't do the cleanup work.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:21 -07:00
Liu Bo
ad9ee2053f Btrfs: fix hang when failing to submit bio of directIO
The hang is uncoverd by generic/019.

btrfs_endio_direct_write() skips the "finish_ordered_fn" part when it hits
an error, thus those added ordered extents will never get processed, which
block processes that waiting for them via btrfs_start_ordered_extent().

This fixes the above, and meanwhile finish_ordered_fn will do the space
accounting work.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:20 -07:00
Filipe Manana
9c6429d96d Btrfs: fix a comment in inode.c:evict_inode_truncate_pages()
The comment was not correct about the part where it says the endio
callback of the bio might have not yet been called - update it
to mention that by that time the endio callback execution might
still be in progress only.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:19 -07:00
Filipe Manana
61de718fce Btrfs: fix memory corruption on failure to submit bio for direct IO
If we fail to submit a bio for a direct IO request, we were grabbing the
corresponding ordered extent and decrementing its reference count twice,
once for our lookup reference and once for the ordered tree reference.
This was a problem because it caused the ordered extent to be freed
without removing it from the ordered tree and any lists it might be
attached to, leaving dangling pointers to the ordered extent around.
Example trace with CONFIG_DEBUG_PAGEALLOC=y:

[161779.858707] BUG: unable to handle kernel paging request at 0000000087654330
[161779.859983] IP: [<ffffffff8124ca68>] rb_prev+0x22/0x3b
[161779.860636] PGD 34d818067 PUD 0
[161779.860636] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
(...)
[161779.860636] Call Trace:
[161779.860636]  [<ffffffffa06b36a6>] __tree_search+0xd9/0xf9 [btrfs]
[161779.860636]  [<ffffffffa06b3708>] tree_search+0x42/0x63 [btrfs]
[161779.860636]  [<ffffffffa06b4868>] ? btrfs_lookup_ordered_range+0x2d/0xa5 [btrfs]
[161779.860636]  [<ffffffffa06b4873>] btrfs_lookup_ordered_range+0x38/0xa5 [btrfs]
[161779.860636]  [<ffffffffa06aab8e>] btrfs_get_blocks_direct+0x11b/0x615 [btrfs]
[161779.860636]  [<ffffffff8119727f>] do_blockdev_direct_IO+0x5ff/0xb43
[161779.860636]  [<ffffffffa06aaa73>] ? btrfs_page_exists_in_range+0x1ad/0x1ad [btrfs]
[161779.860636]  [<ffffffffa06a2c9a>] ? btrfs_get_extent_fiemap+0x1bc/0x1bc [btrfs]
[161779.860636]  [<ffffffff811977f5>] __blockdev_direct_IO+0x32/0x34
[161779.860636]  [<ffffffffa06a2c9a>] ? btrfs_get_extent_fiemap+0x1bc/0x1bc [btrfs]
[161779.860636]  [<ffffffffa06a10ae>] btrfs_direct_IO+0x198/0x21f [btrfs]
[161779.860636]  [<ffffffffa06a2c9a>] ? btrfs_get_extent_fiemap+0x1bc/0x1bc [btrfs]
[161779.860636]  [<ffffffff81112ca1>] generic_file_direct_write+0xb3/0x128
[161779.860636]  [<ffffffffa06affaa>] ? btrfs_file_write_iter+0x15f/0x3e0 [btrfs]
[161779.860636]  [<ffffffffa06b004c>] btrfs_file_write_iter+0x201/0x3e0 [btrfs]
(...)

We were also not freeing the btrfs_dio_private we allocated previously,
which kmemleak reported with the following trace in its sysfs file:

unreferenced object 0xffff8803f553bf80 (size 96):
  comm "xfs_io", pid 4501, jiffies 4295039588 (age 173.936s)
  hex dump (first 32 bytes):
    88 6c 9b f5 02 88 ff ff 00 00 00 00 00 00 00 00  .l..............
    00 00 00 00 00 00 00 00 00 00 c4 00 00 00 00 00  ................
  backtrace:
    [<ffffffff81161ffe>] create_object+0x172/0x29a
    [<ffffffff8145870f>] kmemleak_alloc+0x25/0x41
    [<ffffffff81154e64>] kmemleak_alloc_recursive.constprop.40+0x16/0x18
    [<ffffffff811579ed>] kmem_cache_alloc_trace+0xfb/0x148
    [<ffffffffa03d8cff>] btrfs_submit_direct+0x65/0x16a [btrfs]
    [<ffffffff811968dc>] dio_bio_submit+0x62/0x8f
    [<ffffffff811975fe>] do_blockdev_direct_IO+0x97e/0xb43
    [<ffffffff811977f5>] __blockdev_direct_IO+0x32/0x34
    [<ffffffffa03d70ae>] btrfs_direct_IO+0x198/0x21f [btrfs]
    [<ffffffff81112ca1>] generic_file_direct_write+0xb3/0x128
    [<ffffffffa03e604d>] btrfs_file_write_iter+0x201/0x3e0 [btrfs]
    [<ffffffff8116586a>] __vfs_write+0x7c/0xa5
    [<ffffffff81165da9>] vfs_write+0xa0/0xe4
    [<ffffffff81166675>] SyS_pwrite64+0x64/0x82
    [<ffffffff81464fd7>] system_call_fastpath+0x12/0x6f
    [<ffffffffffffffff>] 0xffffffffffffffff

For read requests we weren't doing any cleanup either (none of the work
done by btrfs_endio_direct_read()), so a failure submitting a bio for a
read request would leave a range in the inode's io_tree locked forever,
blocking any future operations (both reads and writes) against that range.

So fix this by making sure we do the same cleanup that we do for the case
where the bio submission succeeds.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:18 -07:00
Mark Fasheh
1c919a5e13 btrfs: don't update mtime/ctime on deduped inodes
One issue users have reported is that dedupe changes mtime on files,
resulting in tools like rsync thinking that their contents have changed when
in fact the data is exactly the same. We also skip the ctime update as no
user-visible metadata changes here and we want dedupe to be transparent to
the user.

Clone still wants time changes, so we special case this in the code.

This was tested with the btrfs-extent-same tool.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:17 -07:00
Mark Fasheh
0efa9f48c7 btrfs: allow dedupe of same inode
clone() supports cloning within an inode so extent-same can do
the same now. This patch fixes up the locking in extent-same to
know about the single-inode case. In addition to that, we add a
check for overlapping ranges, which clone does not allow.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:15 -07:00
Mark Fasheh
f441460202 btrfs: fix deadlock with extent-same and readpage
->readpage() does page_lock() before extent_lock(), we do the opposite in
extent-same. We want to reverse the order in btrfs_extent_same() but it's
not quite straightforward since the page locks are taken inside btrfs_cmp_data().

So I split btrfs_cmp_data() into 3 parts with a small context structure that
is passed between them. The first, btrfs_cmp_data_prepare() gathers up the
pages needed (taking page lock as required) and puts them on our context
structure. At this point, we are safe to lock the extent range. Afterwards,
we use btrfs_cmp_data() to do the data compare as usual and btrfs_cmp_data_free()
to clean up our context.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:14 -07:00
Mark Fasheh
207910ddee btrfs: pass unaligned length to btrfs_cmp_data()
In the case that we dedupe the tail of a file, we might expand the dedupe
len out to the end of our last block. We don't want to compare data past
i_size however, so pass the original length to btrfs_cmp_data().

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:13 -07:00
Filipe Manana
a89ca6f24f Btrfs: fix fsync after truncate when no_holes feature is enabled
When we have the no_holes feature enabled, if a we truncate a file to a
smaller size, truncate it again but to a size greater than or equals to
its original size and fsync it, the log tree will not have any information
about the hole covering the range [truncate_1_offset, new_file_size[.
Which means if the fsync log is replayed, the file will remain with the
state it had before both truncate operations.

Without the no_holes feature this does not happen, since when the inode
is logged (full sync flag is set) it will find in the fs/subvol tree a
leaf with a generation matching the current transaction id that has an
explicit extent item representing the hole.

Fix this by adding an explicit extent item representing a hole between
the last extent and the inode's i_size if we are doing a full sync.

The issue is easy to reproduce with the following test case for fstests:

  . ./common/rc
  . ./common/filter
  . ./common/dmflakey

  _need_to_be_root
  _supported_fs generic
  _supported_os Linux
  _require_scratch
  _require_dm_flakey

  # This test was motivated by an issue found in btrfs when the btrfs
  # no-holes feature is enabled (introduced in kernel 3.14). So enable
  # the feature if the fs being tested is btrfs.
  if [ $FSTYP == "btrfs" ]; then
      _require_btrfs_fs_feature "no_holes"
      _require_btrfs_mkfs_feature "no-holes"
      MKFS_OPTIONS="$MKFS_OPTIONS -O no-holes"
  fi

  rm -f $seqres.full

  _scratch_mkfs >>$seqres.full 2>&1
  _init_flakey
  _mount_flakey

  # Create our test files and make sure everything is durably persisted.
  $XFS_IO_PROG -f -c "pwrite -S 0xaa 0 64K"         \
                  -c "pwrite -S 0xbb 64K 61K"       \
                  $SCRATCH_MNT/foo | _filter_xfs_io
  $XFS_IO_PROG -f -c "pwrite -S 0xee 0 64K"         \
                  -c "pwrite -S 0xff 64K 61K"       \
                  $SCRATCH_MNT/bar | _filter_xfs_io
  sync

  # Now truncate our file foo to a smaller size (64Kb) and then truncate
  # it to the size it had before the shrinking truncate (125Kb). Then
  # fsync our file. If a power failure happens after the fsync, we expect
  # our file to have a size of 125Kb, with the first 64Kb of data having
  # the value 0xaa and the second 61Kb of data having the value 0x00.
  $XFS_IO_PROG -c "truncate 64K" \
               -c "truncate 125K" \
               -c "fsync" \
               $SCRATCH_MNT/foo

  # Do something similar to our file bar, but the first truncation sets
  # the file size to 0 and the second truncation expands the size to the
  # double of what it was initially.
  $XFS_IO_PROG -c "truncate 0" \
               -c "truncate 253K" \
               -c "fsync" \
               $SCRATCH_MNT/bar

  _load_flakey_table $FLAKEY_DROP_WRITES
  _unmount_flakey

  # Allow writes again, mount to trigger log replay and validate file
  # contents.
  _load_flakey_table $FLAKEY_ALLOW_WRITES
  _mount_flakey

  # We expect foo to have a size of 125Kb, the first 64Kb of data all
  # having the value 0xaa and the remaining 61Kb to be a hole (all bytes
  # with value 0x00).
  echo "File foo content after log replay:"
  od -t x1 $SCRATCH_MNT/foo

  # We expect bar to have a size of 253Kb and no extents (any byte read
  # from bar has the value 0x00).
  echo "File bar content after log replay:"
  od -t x1 $SCRATCH_MNT/bar

  status=0
  exit

The expected file contents in the golden output are:

  File foo content after log replay:
  0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
  *
  0200000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  *
  0372000
  File bar content after log replay:
  0000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  *
  0772000

Without this fix, their contents are:

  File foo content after log replay:
  0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
  *
  0200000 bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
  *
  0372000
  File bar content after log replay:
  0000000 ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee
  *
  0200000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  *
  0372000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  *
  0772000

A test case submission for fstests follows soon.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:12 -07:00
Linus Torvalds
02201e3f1b Minor merge needed, due to function move.
Main excitement here is Peter Zijlstra's lockless rbtree optimization to
 speed module address lookup.  He found some abusers of the module lock
 doing that too.
 
 A little bit of parameter work here too; including Dan Streetman's breaking
 up the big param mutex so writing a parameter can load another module (yeah,
 really).  Unfortunately that broke the usual suspects, !CONFIG_MODULES and
 !CONFIG_SYSFS, so those fixes were appended too.
 
 Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "Main excitement here is Peter Zijlstra's lockless rbtree optimization
  to speed module address lookup.  He found some abusers of the module
  lock doing that too.

  A little bit of parameter work here too; including Dan Streetman's
  breaking up the big param mutex so writing a parameter can load
  another module (yeah, really).  Unfortunately that broke the usual
  suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were
  appended too"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits)
  modules: only use mod->param_lock if CONFIG_MODULES
  param: fix module param locks when !CONFIG_SYSFS.
  rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
  module: add per-module param_lock
  module: make perm const
  params: suppress unused variable error, warn once just in case code changes.
  modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
  kernel/module.c: avoid ifdefs for sig_enforce declaration
  kernel/workqueue.c: remove ifdefs over wq_power_efficient
  kernel/params.c: export param_ops_bool_enable_only
  kernel/params.c: generalize bool_enable_only
  kernel/module.c: use generic module param operaters for sig_enforce
  kernel/params: constify struct kernel_param_ops uses
  sysfs: tightened sysfs permission checks
  module: Rework module_addr_{min,max}
  module: Use __module_address() for module_address_lookup()
  module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
  module: Optimize __module_address() using a latched RB-tree
  rbtree: Implement generic latch_tree
  seqlock: Introduce raw_read_seqcount_latch()
  ...
2015-07-01 10:49:25 -07:00
Eric W. Biederman
93e3bce628 vfs: Remove incorrect debugging WARN in prepend_path
The warning message in prepend_path is unclear and outdated.  It was
added as a warning that the mechanism for generating names of pseudo
files had been removed from prepend_path and d_dname should be used
instead.  Unfortunately the warning reads like a general warning,
making it unclear what to do with it.

Remove the warning.  The transition it was added to warn about is long
over, and I added code several years ago which in rare cases causes
the warning to fire on legitimate code, and the warning is now firing
and scaring people for no good reason.

Cc: stable@vger.kernel.org
Reported-by: Ivan Delalande <colona@arista.com>
Reported-by: Omar Sandoval <osandov@osandov.com>
Fixes: f48cfddc67 ("vfs: In d_path don't call d_dname on a mount point")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:51 -05:00
Eric W. Biederman
7236c85e1b mnt: Update fs_fully_visible to test for permanently empty directories
fs_fully_visible attempts to make fresh mounts of proc and sysfs give
the mounter no more access to proc and sysfs than if they could have
by creating a bind mount.  One aspect of proc and sysfs that makes
this particularly tricky is that there are other filesystems that
typically mount on top of proc and sysfs.  As those filesystems are
mounted on empty directories in practice it is safe to ignore them.
However testing to ensure filesystems are mounted on empty directories
has not been something the in kernel data structures have supported so
the current test for an empty directory which checks to see
if nlink <= 2 is a bit lacking.

proc and sysfs have recently been modified to use the new empty_dir
infrastructure to create all of their dedicated mount points.  Instead
of testing for S_ISDIR(inode->i_mode) && i_nlink <= 2 to see if a
directory is empty, test for is_empty_dir_inode(inode).  That small
change guaranteess mounts found on proc and sysfs really are safe to
ignore, because the directories are not only empty but nothing can
ever be added to them.  This guarantees there is nothing to worry
about when mounting proc and sysfs.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:49 -05:00
Eric W. Biederman
f9bb48825a sysfs: Create mountpoints with sysfs_create_mount_point
This allows for better documentation in the code and
it allows for a simpler and fully correct version of
fs_fully_visible to be written.

The mount points converted and their filesystems are:
/sys/hypervisor/s390/       s390_hypfs
/sys/kernel/config/         configfs
/sys/kernel/debug/          debugfs
/sys/firmware/efi/efivars/  efivarfs
/sys/fs/fuse/connections/   fusectl
/sys/fs/pstore/             pstore
/sys/kernel/tracing/        tracefs
/sys/fs/cgroup/             cgroup
/sys/kernel/security/       securityfs
/sys/fs/selinux/            selinuxfs
/sys/fs/smackfs/            smackfs

Cc: stable@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:47 -05:00
Eric W. Biederman
87d2846fcf sysfs: Add support for permanently empty directories to serve as mount points.
Add two functions sysfs_create_mount_point and
sysfs_remove_mount_point that hang a permanently empty directory off
of a kobject or remove a permanently emptpy directory hanging from a
kobject.  Export these new functions so modular filesystems can use
them.

Cc: stable@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:45 -05:00
Eric W. Biederman
ea015218f2 kernfs: Add support for always empty directories.
Add a new function kernfs_create_empty_dir that can be used to create
directory that can not be modified.

Update the code to use make_empty_dir_inode when reporting a
permanently empty directory to the vfs.

Update the code to not allow adding to permanently empty directories.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:43 -05:00
Eric W. Biederman
eb6d38d542 proc: Allow creating permanently empty directories that serve as mount points
Add a new function proc_create_mount_point that when used to creates a
directory that can not be added to.

Add a new function is_empty_pde to test if a function is a mount
point.

Update the code to use make_empty_dir_inode when reporting
a permanently empty directory to the vfs.

Update the code to not allow adding to permanently empty directories.

Update /proc/openprom and /proc/fs/nfsd to be permanently empty directories.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:41 -05:00
Eric W. Biederman
f9bd6733d3 sysctl: Allow creating permanently empty directories that serve as mountpoints.
Add a magic sysctl table sysctl_mount_point that when used to
create a directory forces that directory to be permanently empty.

Update the code to use make_empty_dir_inode when accessing permanently
empty directories.

Update the code to not allow adding to permanently empty directories.

Update /proc/sys/fs/binfmt_misc to be a permanently empty directory.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:39 -05:00
Eric W. Biederman
fbabfd0f4e fs: Add helper functions for permanently empty directories.
To ensure it is safe to mount proc and sysfs I need to check if
filesystems that are mounted on top of them are mounted on truly empty
directories.  Given that some directories can gain entries over time,
knowing that a directory is empty right now is insufficient.

Therefore add supporting infrastructure for permantently empty
directories that proc and sysfs can use when they create mount points
for filesystems and fs_fully_visible can use to test for permanently
empty directories to ensure that nothing will be gained by mounting a
fresh copy of proc or sysfs.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:37 -05:00
Eric W. Biederman
ceeb0e5d39 vfs: Ignore unlocked mounts in fs_fully_visible
Limit the mounts fs_fully_visible considers to locked mounts.
Unlocked can always be unmounted so considering them adds hassle
but no security benefit.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:35 -05:00