This function is internal to btrfs and doesn't really deal with any
VFS members, as such it needn't take a struct inode refrence but
btrfs_inode.
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently btrfs_ino takes a struct inode and this causes a lot of
internal btrfs functions which consume this ino to take a VFS inode,
rather than btrfs' own struct btrfs_inode. In order to fix this "leak"
of VFS structs into the internals of btrfs first it's necessary to
eliminate all uses of struct inode for the purpose of inode. This patch
does that by using BTRFS_I to convert an inode to btrfs_inode. With
this problem eliminated subsequent patches will start eliminating the
passing of struct inode altogether, eventually resulting in a lot cleaner
code.
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
[ fix btrfs_get_extent tracepoint prototype ]
Signed-off-by: David Sterba <dsterba@suse.com>
The expression is open-coded in several places, this asks for a wrapper.
As we know the MAX_EXTENT fits to u32, we can use the appropirate
division helper. This cascades to the result type updates.
Compiler is clever enough to use shift instead of integer division, so
there's no change in the generated assembly.
Signed-off-by: David Sterba <dsterba@suse.com>
A proposed patch in https://marc.info/?l=linux-btrfs&m=147859791003837
pointed out bad limit threshold in cow_file_range_async, but it turned
out that the whole logic is not necessary and is done by writeback. We
agreed to remove it.
Signed-off-by: David Sterba <dsterba@suse.com>
As of now writes smaller than 64k for non compressed extents and 16k
for compressed extents inside eof are considered as candidate
for auto defrag, put them together at a place.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since btrfs_defrag_leaves() does not support extent_root, remove its
corresponding call. The user can use the file based defrag to defrag
extents as of now.
No change in behaviour as extent_root is explicitly skipped in
btrfs_defrag_leaves and this has never worked as expected.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ ehnance changelong ]
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_add_delayed_data_ref is always called with a NULL extent_op,
so let's drop the argument.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The check for a null inode is redundant since the function
is a callback for exportfs, which will itself crash if
dentry->d_inode or parent->d_inode is NULL. Removing the
null check makes this consistent with other file systems.
Also remove the redundant null dir check too.
Found with static analysis by CoverityScan, CID 1389472
Kudos to Jeff Mahoney for reviewing and explaining the error in
my original patch (most of this explanation went into the above
commit message) and David Sterba for pointing out that the dir
check is also redundant.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This replaces ACCESS_ONCE macro with the corresponding
READ|WRITE macros
Signed-off-by: Seraphime Kirkovski <kirkseraph@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This cleans up the cases where the min/max macros were used with a cast
rather than using directly min_t/max_t.
Signed-off-by: Seraphime Kirkovski <kirkseraph@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
To make the code clearer, use rb_entry() instead of container_of() to
deal with rbtree.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
try_release_extent_state reduces the gfp mask to GFP_NOFS if it is
compatible. This is true for GFP_KERNEL as well. There is no real
reason to do that though. There is no new lock taken down the
the only consumer of the gfp mask which is
try_release_extent_state
clear_extent_bit
__clear_extent_bit
alloc_extent_state
So this seems just unnecessary and confusing.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
b335b0034e ("Btrfs: Avoid using __GFP_HIGHMEM with slab allocator")
has reduced the allocation mask in btrfs_releasepage to GFP_NOFS just
to prevent from giving an unappropriate gfp mask to the slab allocator
deeper down the callchain (in alloc_extent_state). This is wrong for
two reasons a) GFP_NOFS might be just too restrictive for the calling
context b) it is better to tweak the gfp mask down when it needs that.
So just remove the mask tweaking from btrfs_releasepage and move it
down to alloc_extent_state where it is needed.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Goldwyn Rodrigues has exposed and fixed a bug which underflows btrfs
qgroup reserved space, and leads to non-writable fs.
This reminds us that we don't have enough underflow check for qgroup
reserved space.
For underflow case, we should not really underflow the numbers but warn
and keeps qgroup still work.
So add more check on qgroup reserved space and add WARN_ON() and
btrfs_warn() for any underflow case.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull btrfs fixes from Chris Mason:
"This has two last minute fixes. The highest priority here is a
regression fix for the decompression code, but we also fixed up a
problem with the 32-bit compat ioctls.
The decompression bug could hand back the wrong data on big reads when
zlib was used. I have a larger cleanup to make the math here less
error prone, but at this stage in the release Omar's patch is the best
choice"
* 'for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: fix btrfs_decompress_buf2page()
btrfs: fix btrfs_compat_ioctl failures on non-compat ioctls
If btrfs_decompress_buf2page() is handed a bio with its page in the
middle of the working buffer, then we adjust the offset into the working
buffer. After we copy into the bio, we advance the iterator by the
number of bytes we copied. Then, we have some logic to handle the case
of discontiguous pages and adjust the offset into the working buffer
again. However, if we didn't advance the bio to a new page, we may enter
this case in error, essentially repeating the adjustment that we already
made when we entered the function. The end result is bogus data in the
bio.
Previously, we only checked for this case when we advanced to a new
page, but the conversion to bio iterators changed that. This restores
the old, correct behavior.
A case I saw when testing with zlib was:
buf_start = 42769
total_out = 46865
working_bytes = total_out - buf_start = 4096
start_byte = 45056
The condition (total_out > start_byte && buf_start < start_byte) is
true, so we adjust the offset:
buf_offset = start_byte - buf_start = 2287
working_bytes -= buf_offset = 1809
current_buf_start = buf_start = 42769
Then, we copy
bytes = min(bvec.bv_len, PAGE_SIZE - buf_offset, working_bytes) = 1809
buf_offset += bytes = 4096
working_bytes -= bytes = 0
current_buf_start += bytes = 44578
After bio_advance(), we are still in the same page, so start_byte is the
same. Then, we check (total_out > start_byte && current_buf_start < start_byte),
which is true! So, we adjust the values again:
buf_offset = start_byte - buf_start = 2287
working_bytes = total_out - start_byte = 1809
current_buf_start = buf_start + buf_offset = 45056
But note that working_bytes was already zero before this, so we should
have stopped copying.
Fixes: 974b1adc3b ("btrfs: use bio iterators for the decompression handlers")
Reported-by: Pat Erley <pat-lkml@erley.org>
Reviewed-by: Chris Mason <clm@fb.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Tested-by: Liu Bo <bo.li.liu@oracle.com>
fixable, but at least one of the fixes is a little ugly. The original
bug has always been there, so we can wait another week or two to get
this right.
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Merge tag 'nfsd-4.10-3' of git://linux-nfs.org/~bfields/linux
Pull nfsd revert from Bruce Fields:
"This patch turned out to have a couple problems. The problems are
fixable, but at least one of the fixes is a little ugly. The original
bug has always been there, so we can wait another week or two to get
this right"
* tag 'nfsd-4.10-3' of git://linux-nfs.org/~bfields/linux:
nfsd: Revert "nfsd: special case truncates some more"
This patch incorrectly attempted nested mnt_want_write, and incorrectly
disabled nfsd's owner override for truncate. We'll fix those problems
and make another attempt soon, for the moment I think the safest is to
revert.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We'll OOPS in ramoops_get_next_prz() if the platform didn't ask for any
ftrace zones (i.e., cxt->fprzs will be NULL). Let's just skip this
entire FTRACE section if there's no 'fprzs'.
Regression seen on a coreboot/depthcharge-based Chromebook.
Fixes: 2fbea82bbb ("pstore: Merge per-CPU ftrace records into one")
Cc: Joel Fernandes <joelaf@google.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Commit 4c63c2454e incorrectly assumed that returning -ENOIOCTLCMD would
cause the native ioctl to be called. The ->compat_ioctl callback is
expected to handle all ioctls, not just compat variants. As a result,
when using 32-bit userspace on 64-bit kernels, everything except those
three ioctls would return -ENOTTY.
Fixes: 4c63c2454e ("btrfs: bugfix: handle FS_IOC32_{GETFLAGS,SETFLAGS,GETVERSION} in btrfs_ioctl")
Cc: stable@vger.kernel.org
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit 6326fec112 ("mm: Use owner_priv bit for PageSwapCache, valid
when PageSwapBacked") aliased PG_swapcache to PG_owner_priv_1 (and
depending on PageSwapBacked being true).
As a result, the KPF_SWAPCACHE bit in '/proc/kpageflags' should now be
synthesized, instead of being shown on unrelated pages which just happen
to have PG_owner_priv_1 set.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tetsuo has noticed that an OOM stress test which performs large write
requests can cause the full memory reserves depletion. He has tracked
this down to the following path
__alloc_pages_nodemask+0x436/0x4d0
alloc_pages_current+0x97/0x1b0
__page_cache_alloc+0x15d/0x1a0 mm/filemap.c:728
pagecache_get_page+0x5a/0x2b0 mm/filemap.c:1331
grab_cache_page_write_begin+0x23/0x40 mm/filemap.c:2773
iomap_write_begin+0x50/0xd0 fs/iomap.c:118
iomap_write_actor+0xb5/0x1a0 fs/iomap.c:190
? iomap_write_end+0x80/0x80 fs/iomap.c:150
iomap_apply+0xb3/0x130 fs/iomap.c:79
iomap_file_buffered_write+0x68/0xa0 fs/iomap.c:243
? iomap_write_end+0x80/0x80
xfs_file_buffered_aio_write+0x132/0x390 [xfs]
? remove_wait_queue+0x59/0x60
xfs_file_write_iter+0x90/0x130 [xfs]
__vfs_write+0xe5/0x140
vfs_write+0xc7/0x1f0
? syscall_trace_enter+0x1d0/0x380
SyS_write+0x58/0xc0
do_syscall_64+0x6c/0x200
entry_SYSCALL64_slow_path+0x25/0x25
the oom victim has access to all memory reserves to make a forward
progress to exit easier. But iomap_file_buffered_write and other
callers of iomap_apply loop to complete the full request. We need to
check for fatal signals and back off with a short write instead.
As the iomap_apply delegates all the work down to the actor we have to
hook into those. All callers that work with the page cache are calling
iomap_write_begin so we will check for signals there. dax_iomap_actor
has to handle the situation explicitly because it copies data to the
userspace directly. Other callers like iomap_page_mkwrite work on a
single page or iomap_fiemap_actor do not allocate memory based on the
given len.
Fixes: 68a9f5e700 ("xfs: implement iomap based buffered write path")
Link: http://lkml.kernel.org/r/20170201092706.9966-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org> [4.8+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'nfsd-4.10-2' of git://linux-nfs.org/~bfields/linux
Pull nfsd fixes from Bruce Fields:
"Three more miscellaneous nfsd bugfixes"
* tag 'nfsd-4.10-2' of git://linux-nfs.org/~bfields/linux:
svcrpc: fix oops in absence of krb5 module
nfsd: special case truncates some more
NFSD: Fix a null reference case in find_or_create_lock_stateid()
Pull fscache fixes from Al Viro.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fscache: Fix dead object requeue
fscache: Clear outstanding writes when disabling a cookie
FS-Cache: Initialise stores_lock in netfs cookie
Under some circumstances, an fscache object can become queued such that it
fscache_object_work_func() can be called once the object is in the
OBJECT_DEAD state. This results in the kernel oopsing when it tries to
invoke the handler for the state (which is hard coded to 0x2).
The way this comes about is something like the following:
(1) The object dispatcher is processing a work state for an object. This
is done in workqueue context.
(2) An out-of-band event comes in that isn't masked, causing the object to
be queued, say EV_KILL.
(3) The object dispatcher finishes processing the current work state on
that object and then sees there's another event to process, so,
without returning to the workqueue core, it processes that event too.
It then follows the chain of events that initiates until we reach
OBJECT_DEAD without going through a wait state (such as
WAIT_FOR_CLEARANCE).
At this point, object->events may be 0, object->event_mask will be 0
and oob_event_mask will be 0.
(4) The object dispatcher returns to the workqueue processor, and in due
course, this sees that the object's work item is still queued and
invokes it again.
(5) The current state is a work state (OBJECT_DEAD), so the dispatcher
jumps to it - resulting in an OOPS.
When I'm seeing this, the work state in (1) appears to have been either
LOOK_UP_OBJECT or CREATE_OBJECT (object->oob_table is
fscache_osm_lookup_oob).
The window for (2) is very small:
(A) object->event_mask is cleared whilst the event dispatch process is
underway - though there's no memory barrier to force this to the top
of the function.
The window, therefore is from the time the object was selected by the
workqueue processor and made requeueable to the time the mask was
cleared.
(B) fscache_raise_event() will only queue the object if it manages to set
the event bit and the corresponding event_mask bit was set.
The enqueuement is then deferred slightly whilst we get a ref on the
object and get the per-CPU variable for workqueue congestion. This
slight deferral slightly increases the probability by allowing extra
time for the workqueue to make the item requeueable.
Handle this by giving the dead state a processor function and checking the
for the dead state address rather than seeing if the processor function is
address 0x2. The dead state processor function can then set a flag to
indicate that it's occurred and give a warning if it occurs more than once
per object.
If this race occurs, an oops similar to the following is seen (note the RIP
value):
BUG: unable to handle kernel NULL pointer dereference at 0000000000000002
IP: [<0000000000000002>] 0x1
PGD 0
Oops: 0010 [#1] SMP
Modules linked in: ...
CPU: 17 PID: 16077 Comm: kworker/u48:9 Not tainted 3.10.0-327.18.2.el7.x86_64 #1
Hardware name: HP ProLiant DL380 Gen9/ProLiant DL380 Gen9, BIOS P89 12/27/2015
Workqueue: fscache_object fscache_object_work_func [fscache]
task: ffff880302b63980 ti: ffff880717544000 task.ti: ffff880717544000
RIP: 0010:[<0000000000000002>] [<0000000000000002>] 0x1
RSP: 0018:ffff880717547df8 EFLAGS: 00010202
RAX: ffffffffa0368640 RBX: ffff880edf7a4480 RCX: dead000000200200
RDX: 0000000000000002 RSI: 00000000ffffffff RDI: ffff880edf7a4480
RBP: ffff880717547e18 R08: 0000000000000000 R09: dfc40a25cb3a4510
R10: dfc40a25cb3a4510 R11: 0000000000000400 R12: 0000000000000000
R13: ffff880edf7a4510 R14: ffff8817f6153400 R15: 0000000000000600
FS: 0000000000000000(0000) GS:ffff88181f420000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000002 CR3: 000000000194a000 CR4: 00000000001407e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
ffffffffa0363695 ffff880edf7a4510 ffff88093f16f900 ffff8817faa4ec00
ffff880717547e60 ffffffff8109d5db 00000000faa4ec18 0000000000000000
ffff8817faa4ec18 ffff88093f16f930 ffff880302b63980 ffff88093f16f900
Call Trace:
[<ffffffffa0363695>] ? fscache_object_work_func+0xa5/0x200 [fscache]
[<ffffffff8109d5db>] process_one_work+0x17b/0x470
[<ffffffff8109e4ac>] worker_thread+0x21c/0x400
[<ffffffff8109e290>] ? rescuer_thread+0x400/0x400
[<ffffffff810a5acf>] kthread+0xcf/0xe0
[<ffffffff810a5a00>] ? kthread_create_on_node+0x140/0x140
[<ffffffff816460d8>] ret_from_fork+0x58/0x90
[<ffffffff810a5a00>] ? kthread_create_on_node+0x140/0x140
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeremy McNicoll <jeremymc@redhat.com>
Tested-by: Frank Sorenson <sorenson@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
fscache_disable_cookie() needs to clear the outstanding writes on the
cookie it's disabling because they cannot be completed after.
Without this, fscache_nfs_open_file() gets stuck because it disables the
cookie when the file is opened for writing but can't uncache the pages till
afterwards - otherwise there's a race between the open routine and anyone
who already has it open R/O and is still reading from it.
Looking in /proc/pid/stack of the offending process shows:
[<ffffffffa0142883>] __fscache_wait_on_page_write+0x82/0x9b [fscache]
[<ffffffffa014336e>] __fscache_uncache_all_inode_pages+0x91/0xe1 [fscache]
[<ffffffffa01740fa>] nfs_fscache_open_file+0x59/0x9e [nfs]
[<ffffffffa01ccf41>] nfs4_file_open+0x17f/0x1b8 [nfsv4]
[<ffffffff8117350e>] do_dentry_open+0x16d/0x2b7
[<ffffffff811743ac>] vfs_open+0x5c/0x65
[<ffffffff81184185>] path_openat+0x785/0x8fb
[<ffffffff81184343>] do_filp_open+0x48/0x9e
[<ffffffff81174710>] do_sys_open+0x13b/0x1cb
[<ffffffff811747b9>] SyS_open+0x19/0x1b
[<ffffffff81001c44>] do_syscall_64+0x80/0x17a
[<ffffffff8165c2da>] return_from_SYSCALL_64+0x0/0x7a
[<ffffffffffffffff>] 0xffffffffffffffff
Reported-by: Jianhong Yin <jiyin@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Initialise the stores_lock in fscache netfs cookies. Technically, it
shouldn't be necessary, since the netfs cookie is an index and stores no
data, but initialising it anyway adds insignificant overhead.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Both the NFS protocols and the Linux VFS use a setattr operation with a
bitmap of attributs to set to set various file attributes including the
file size and the uid/gid.
The Linux syscalls never mixes size updates with unrelated updates like
the uid/gid, and some file systems like XFS and GFS2 rely on the fact
that truncates might not update random other attributes, and many other
file systems handle the case but do not update the different attributes
in the same transaction. NFSD on the other hand passes the attributes
it gets on the wire more or less directly through to the VFS, leading to
updates the file systems don't expect. XFS at least has an assert on
the allowed attributes, which caught an unusual NFS client setting the
size and group at the same time.
To handle this issue properly this switches nfsd to call vfs_truncate
for size changes, and then handle all other attributes through
notify_change. As a side effect this also means less boilerplace code
around the size change as we can now reuse the VFS code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd assigns the nfs4_free_lock_stateid to .sc_free in init_lock_stateid().
If nfsd doesn't go through init_lock_stateid() and put stateid at end,
there is a NULL reference to .sc_free when calling nfs4_put_stid(ns).
This patch let the nfs4_stid.sc_free assignment to nfs4_alloc_stid().
Cc: stable@vger.kernel.org
Fixes: 356a95ece7 "nfsd: clean up races in lock stateid searching..."
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Stable patches:
- NFSv4.1: Fix a deadlock in layoutget
- NFSv4 must not bump sequence ids on NFS4ERR_MOVED errors
- NFSv4 Fix a regression with OPEN EXCLUSIVE4 mode
- Fix a memory leak when removing the SUNRPC module
Bugfixes:
- Fix a reference leak in _pnfs_return_layout
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Merge tag 'nfs-for-4.10-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Stable patches:
- NFSv4.1: Fix a deadlock in layoutget
- NFSv4 must not bump sequence ids on NFS4ERR_MOVED errors
- NFSv4 Fix a regression with OPEN EXCLUSIVE4 mode
- Fix a memory leak when removing the SUNRPC module
Bugfixes:
- Fix a reference leak in _pnfs_return_layout"
* tag 'nfs-for-4.10-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
pNFS: Fix a reference leak in _pnfs_return_layout
nfs: Fix "Don't increment lock sequence ID after NFS4ERR_MOVED"
SUNRPC: cleanup ida information when removing sunrpc module
NFSv4.0: always send mode in SETATTR after EXCLUSIVE4
nfs: Don't increment lock sequence ID after NFS4ERR_MOVED
NFSv4.1: Fix a deadlock in layoutget
- Fix race conditions in the CoW code
- Fix some incorrect input validation checks
- Avoid crashing fs by running out of space when freeing inodes
- Fix toctou race wrt whether or not an inode has an attr
- Fix build error on arm
- Fix page refcount corruption when readahead fails
- Don't corrupt userspace in the bmap ioctl
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Merge tag 'xfs-for-linus-4.10-rc6-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs uodates from Darrick Wong:
"I have some more fixes this week: better input validation, corruption
avoidance, build fixes, memory leak fixes, and a couple from Christoph
to avoid an ENOSPC failure.
Summary:
- Fix race conditions in the CoW code
- Fix some incorrect input validation checks
- Avoid crashing fs by running out of space when freeing inodes
- Fix toctou race wrt whether or not an inode has an attr
- Fix build error on arm
- Fix page refcount corruption when readahead fails
- Don't corrupt userspace in the bmap ioctl"
* tag 'xfs-for-linus-4.10-rc6-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: prevent quotacheck from overloading inode lru
xfs: fix bmv_count confusion w/ shared extents
xfs: clear _XBF_PAGES from buffers when readahead page
xfs: extsize hints are not unlikely in xfs_bmap_btalloc
xfs: remove racy hasattr check from attr ops
xfs: use per-AG reservations for the finobt
xfs: only update mount/resv fields on success in __xfs_ag_resv_init
xfs: verify dirblocklog correctly
xfs: fix COW writeback race
Pull btrfs updates from Chris Mason:
"Some fixes that we've collected from the list.
We still have one more pending to nail down a regression in lzo
compression, but I wanted to get this batch out the door"
* 'for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: remove ->{get, set}_acl() from btrfs_dir_ro_inode_operations
Btrfs: disable xattr operations on subvolume directories
Btrfs: remove old tree_root case in btrfs_read_locked_inode()
Btrfs: fix truncate down when no_holes feature is enabled
Btrfs: Fix deadlock between direct IO and fast fsync
btrfs: fix false enospc error when truncating heavily reflinked file
Pull block fixes from Jens Axboe:
"A set of fixes for this series. This contains:
- Set of fixes for the nvme target code
- A revert of patch from this merge window, causing a regression with
WRITE_SAME on iSCSI targets at least.
- A fix for a use-after-free in the new O_DIRECT bdev code.
- Two fixes for the xen-blkfront driver"
* 'for-linus' of git://git.kernel.dk/linux-block:
Revert "sd: remove __data_len hack for WRITE SAME"
nvme-fc: use blk_rq_nr_phys_segments
nvmet-rdma: Fix missing dma sync to nvme data structures
nvmet: Call fatal_error from keep-alive timout expiration
nvmet: cancel fatal error and flush async work before free controller
nvmet: delete controllers deletion upon subsystem release
nvmet_fc: correct logic in disconnect queue LS handling
block: fix use after free in __blkdev_direct_IO
xen-blkfront: correct maximum segment accounting
xen-blkfront: feature flags handling adjustments
Quotacheck runs at mount time in situations where quota accounting must
be recalculated. In doing so, it uses bulkstat to visit every inode in
the filesystem. Historically, every inode processed during quotacheck
was released and immediately tagged for reclaim because quotacheck runs
before the superblock is marked active by the VFS. In other words,
the final iput() lead to an immediate ->destroy_inode() call, which
allowed the XFS background reclaim worker to start reclaiming inodes.
Commit 17c12bcd3 ("xfs: when replaying bmap operations, don't let
unlinked inodes get reaped") marks the XFS superblock active sooner as
part of the mount process to support caching inodes processed during log
recovery. This occurs before quotacheck and thus means all inodes
processed by quotacheck are inserted to the LRU on release. The
s_umount lock is held until the mount has completed and thus prevents
the shrinkers from operating on the sb. This means that quotacheck can
excessively populate the inode LRU and lead to OOM conditions on systems
without sufficient RAM.
Update the quotacheck bulkstat handler to set XFS_IGET_DONTCACHE on
inodes processed by quotacheck. This causes ->drop_inode() to return 1
and in turn causes iput_final() to evict the inode. This preserves the
original quotacheck behavior and prevents it from overloading the LRU
and running out of memory.
CC: stable@vger.kernel.org # v4.9
Reported-by: Martin Svec <martin.svec@zoner.cz>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
When you snapshot a subvolume containing a subvolume, you get a
placeholder directory where the subvolume would be. These directory
inodes have ->i_ops set to btrfs_dir_ro_inode_operations. Previously,
these i_ops didn't include the xattr operation callbacks. The conversion
to xattr_handlers missed this case, leading to bogus attempts to set
xattrs on these inodes. This manifested itself as failures when running
delayed inodes.
To fix this, clear IOP_XATTR in ->i_opflags on these inodes.
Fixes: 6c6ef9f26e ("xattr: Stop calling {get,set,remove}xattr inode operations")
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Reported-by: Chris Murphy <lists@colorremedies.com>
Tested-by: Chris Murphy <lists@colorremedies.com>
Cc: <stable@vger.kernel.org> # 4.9.x
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
As Jeff explained in c2951f32d3 ("btrfs: remove old tree_root dirent
processing in btrfs_real_readdir()"), supporting this old format is no
longer necessary since the Btrfs magic number has been updated since we
changed to the current format. There are other places where we still
handle this old format, but since this is part of a fix that is going to
stable, I'm only removing this one for now.
Cc: <stable@vger.kernel.org> # 4.9.x
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
IF NFS_LAYOUT_RETURN_REQUESTED is not set, then we currently exit
without freeing the list of invalidated layout segments, leading
to a reference leak.
Reported-by: Olga Kornievskaia <aglo@umich.edu>
Fixes: 24408f5282 ("pNFS: Fix bugs in _pnfs_return_layout")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Lock sequence IDs are bumped in decode_lock by calling
nfs_increment_seqid(). nfs_increment_sequid() does not use the
seqid_mutating_err() function fixed in commit 059aa73482 ("Don't
increment lock sequence ID after NFS4ERR_MOVED").
Fixes: 059aa73482 ("Don't increment lock sequence ID after ...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Xuan Qi <xuan.qi@oracle.com>
Cc: stable@vger.kernel.org # v3.7+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
In a bmapx call, bmv_count is the total size of the array, including the
zeroth element that userspace uses to supply the search key. The output
array starts at offset 1 so that we can set up the user for the next
invocation. Since we now can split an extent into multiple bmap records
due to shared/unshared status, we have to be careful that we don't
overflow the output array.
In the original patch f86f403794 ("xfs: teach get_bmapx about shared
extents and the CoW fork") I used cur_ext (the output index) to check
for overflows, albeit with an off-by-one error. Since nexleft no longer
describes the number of unfilled slots in the output, we can rip all
that out and use cur_ext for the overflow check directly.
Failure to do this causes heap corruption in bmapx callers such as
xfs_io and xfs_scrub. xfs/328 can reproduce this problem.
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
If we try to allocate memory pages to back an xfs_buf that we're trying
to read, it's possible that we'll be so short on memory that the page
allocation fails. For a blocking read we'll just wait, but for
readahead we simply dump all the pages we've collected so far.
Unfortunately, after dumping the pages we neglect to clear the
_XBF_PAGES state, which means that the subsequent call to xfs_buf_free
thinks that b_pages still points to pages we own. It then double-frees
the b_pages pages.
This results in screaming about negative page refcounts from the memory
manager, which xfs oughtn't be triggering. To reproduce this case,
mount a filesystem where the size of the inodes far outweighs the
availalble memory (a ~500M inode filesystem on a VM with 300MB memory
did the trick here) and run bulkstat in parallel with other memory
eating processes to put a huge load on the system. The "check summary"
phase of xfs_scrub also works for this purpose.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
With COW files they are the hotpath, just like for files with the
extent size hint attribute. We really shouldn't micro-manage anything
but failure cases with unlikely.
Additionally Arnd Bergmann recently reported that one of these two
unlikely annotations causes link failures together with an upcoming
kernel instrumentation patch, so let's get rid of it ASAP.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
xfs_attr_[get|remove]() have unlocked attribute fork checks to optimize
away a lock cycle in cases where the fork does not exist or is otherwise
empty. This check is not safe, however, because an attribute fork short
form to extent format conversion includes a transient state that causes
the xfs_inode_hasattr() check to fail. Specifically,
xfs_attr_shortform_to_leaf() creates an empty extent format attribute
fork and then adds the existing shortform attributes to it.
This means that lookup of an existing xattr can spuriously return
-ENOATTR when racing against a setxattr that causes the associated
format conversion. This was originally reproduced by an untar on a
particularly configured glusterfs volume, but can also be reproduced on
demand with properly crafted xattr requests.
The format conversion occurs under the exclusive ilock. xfs_attr_get()
and xfs_attr_remove() already have the proper locking and checks further
down in the functions to handle this situation correctly. Drop the
unlocked checks to avoid the spurious failure and rely on the existing
logic.
Signed-off-by: Brian Foster <bfoster@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>
Currently we try to rely on the global reserved block pool for block
allocations for the free inode btree, but I have customer reports
(fairly complex workload, need to find an easier reproducer) where that
is not enough as the AG where we free an inode that requires a new
finobt block is entirely full. This causes us to cancel a dirty
transaction and thus a file system shutdown.
I think the right way to guard against this is to treat the finot the same
way as the refcount btree and have a per-AG reservations for the possible
worst case size of it, and the patch below implements that.
Note that this could increase mount times with large finobt trees. In
an ideal world we would have added a field for the number of finobt
fields to the AGI, similar to what we did for the refcount blocks.
We should do add it next time we rev the AGI or AGF format by adding
new fields.
Signed-off-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>
Try to reserve the blocks first and only then update the fields in
or hanging off the mount structure. This way we can call __xfs_ag_resv_init
again after a previous failure.
Signed-off-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>
Commit 8a59f5d252 ("fs/romfs: return f_fsid for statfs(2)") generates
a 64bit id from sb->s_bdev->bd_dev. This is only correct when romfs is
defined with CONFIG_ROMFS_ON_BLOCK. If romfs is only defined with
CONFIG_ROMFS_ON_MTD, sb->s_bdev is NULL, referencing sb->s_bdev->bd_dev
will triger an oops.
Richard Weinberger points out that when CONFIG_ROMFS_BACKED_BY_BOTH=y,
both CONFIG_ROMFS_ON_BLOCK and CONFIG_ROMFS_ON_MTD are defined.
Therefore when calling huge_encode_dev() to generate a 64bit id, I use
the follow order to choose parameter,
- CONFIG_ROMFS_ON_BLOCK defined
use sb->s_bdev->bd_dev
- CONFIG_ROMFS_ON_BLOCK undefined and CONFIG_ROMFS_ON_MTD defined
use sb->s_dev when,
- both CONFIG_ROMFS_ON_BLOCK and CONFIG_ROMFS_ON_MTD undefined
leave id as 0
When CONFIG_ROMFS_ON_MTD is defined and sb->s_mtd is not NULL, sb->s_dev
is set to a device ID generated by MTD_BLOCK_MAJOR and mtd index,
otherwise sb->s_dev is 0.
This is a try-best effort to generate a uniq file system ID, if all the
above conditions are not meet, f_fsid of this romfs instance will be 0.
Generally only one romfs can be built on single MTD block device, this
method is enough to identify multiple romfs instances in a computer.
Link: http://lkml.kernel.org/r/1482928596-115155-1-git-send-email-colyli@suse.de
Signed-off-by: Coly Li <colyli@suse.de>
Reported-by: Nong Li <nongli1031@gmail.com>
Tested-by: Nong Li <nongli1031@gmail.com>
Cc: Richard Weinberger <richard.weinberger@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We have seen proc_pid_readdir() invocations holding cpu for more than 50
ms. Add a cond_resched() to be gentle with other tasks.
[akpm@linux-foundation.org: coding style fix]
Link: http://lkml.kernel.org/r/1484238380.15816.42.camel@edumazet-glaptop3.roam.corp.google.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With >=32 CPUs the userfaultfd selftest triggered a graceful but
unexpected SIGBUS because VM_FAULT_RETRY was returned by
handle_userfault() despite the UFFDIO_COPY wasn't completed.
This seems caused by rwsem waking the thread blocked in
handle_userfault() and we can't run up_read() before the wait_event
sequence is complete.
Keeping the wait_even sequence identical to the first one, would require
running userfaultfd_must_wait() again to know if the loop should be
repeated, and it would also require retaking the rwsem and revalidating
the whole vma status.
It seems simpler to wait the targeted wakeup so that if false wakeups
materialize we still wait for our specific wakeup event, unless of
course there are signals or the uffd was released.
Debug code collecting the stack trace of the wakeup showed this:
$ ./userfaultfd 100 99999
nr_pages: 25600, nr_pages_per_cpu: 800
bounces: 99998, mode: racing ver poll, userfaults: 32 35 90 232 30 138 69 82 34 30 139 40 40 31 20 19 43 13 15 28 27 38 21 43 56 22 1 17 31 8 4 2
bounces: 99997, mode: rnd ver poll, Bus error (core dumped)
save_stack_trace+0x2b/0x50
try_to_wake_up+0x2a6/0x580
wake_up_q+0x32/0x70
rwsem_wake+0xe0/0x120
call_rwsem_wake+0x1b/0x30
up_write+0x3b/0x40
vm_mmap_pgoff+0x9c/0xc0
SyS_mmap_pgoff+0x1a9/0x240
SyS_mmap+0x22/0x30
entry_SYSCALL_64_fastpath+0x1f/0xbd
0xffffffffffffffff
FAULT_FLAG_ALLOW_RETRY missing 70
CPU: 24 PID: 1054 Comm: userfaultfd Tainted: G W 4.8.0+ #30
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
Call Trace:
dump_stack+0xb8/0x112
handle_userfault+0x572/0x650
handle_mm_fault+0x12cb/0x1520
__do_page_fault+0x175/0x500
trace_do_page_fault+0x61/0x270
do_async_page_fault+0x19/0x90
async_page_fault+0x25/0x30
This always happens when the main userfault selftest thread is running
clone() while glibc runs either mprotect or mmap (both taking mmap_sem
down_write()) to allocate the thread stack of the background threads,
while locking/userfault threads already run at full throttle and are
susceptible to false wakeups that may cause handle_userfault() to return
before than expected (which results in graceful SIGBUS at the next
attempt).
This was reproduced only with >=32 CPUs because the loop to start the
thread where clone() is too quick with fewer CPUs, while with 32 CPUs
there's already significant activity on ~32 locking and userfault
threads when the last background threads are started with clone().
This >=32 CPUs SMP race condition is likely reproducible only with the
selftest because of the much heavier userfault load it generates if
compared to real apps.
We'll have to allow "one more" VM_FAULT_RETRY for the WP support and a
patch floating around that provides it also hidden this problem but in
reality only is successfully at hiding the problem.
False wakeups could still happen again the second time
handle_userfault() is invoked, even if it's a so rare race condition
that getting false wakeups twice in a row is impossible to reproduce.
This full fix is needed for correctness, the only alternative would be
to allow VM_FAULT_RETRY to be returned infinitely. With this fix the WP
support can stick to a strict "one more" VM_FAULT_RETRY logic (no need
of returning it infinite times to avoid the SIGBUS).
Link: http://lkml.kernel.org/r/20170111005535.13832-2-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Shubham Kumar Sharma <shubham.kumar.sharma@oracle.com>
Tested-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michael Rapoport <RAPOPORT@il.ibm.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
