Commit Graph

50103 Commits

Author SHA1 Message Date
Qu Wenruo
d10b82fe29 btrfs: Allow barrier_all_devices to do chunk level device check
The last user of num_tolerated_disk_barrier_failures is
barrier_all_devices().
But it can be easily changed to the new per-chunk degradable check
framework.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:02 +02:00
Qu Wenruo
b382cfe889 btrfs: Do chunk level check for degraded remount
Just the same for mount time check, use btrfs_check_rw_degradable() to
check if we are OK to be remounted rw.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:02 +02:00
Qu Wenruo
4330e183c9 btrfs: Do chunk level check for degraded rw mount
Now use the btrfs_check_rw_degradable() to check if we can mount in the
degraded mode.

With this patch, we can mount in the following case:
 # mkfs.btrfs -f -m raid1 -d single /dev/sdb /dev/sdc
 # wipefs -a /dev/sdc
 # mount /dev/sdb /mnt/btrfs -o degraded
 As the single data chunk is only on sdb, so it's OK to mount as
 degraded, as missing one device is OK for RAID1.

But still fail in the following case as expected:
 # mkfs.btrfs -f -m raid1 -d single /dev/sdb /dev/sdc
 # wipefs -a /dev/sdb
 # mount /dev/sdc /mnt/btrfs -o degraded
 As the data chunk is only in sdb, so it's not OK to mount it as
 degraded.

Reported-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Reported-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:02 +02:00
Qu Wenruo
21634a19f6 btrfs: Introduce a function to check if all chunks a OK for degraded rw mount
Introduce a new function, btrfs_check_rw_degradable(), to check if all
chunks in btrfs is OK for degraded rw mount.

It provides the new basis for accurate btrfs mount/remount and even
runtime degraded mount check other than old one-size-fit-all method.

Btrfs currently uses num_tolerated_disk_barrier_failures to do global
check for tolerated missing device.

Although the one-size-fit-all solution is quite safe, it's too strict
if data and metadata has different duplication level.

For example, if one use Single data and RAID1 metadata for 2 disks, it
means any missing device will make the fs unable to be degraded
mounted.

But in fact, some times all single chunks may be in the existing
device and in that case, we should allow it to be rw degraded mounted.

Such case can be easily reproduced using the following script:
 # mkfs.btrfs -f -m raid1 -d sing /dev/sdb /dev/sdc
 # wipefs -f /dev/sdc
 # mount /dev/sdb -o degraded,rw

If using btrfs-debug-tree to check /dev/sdb, one should find that the
data chunk is only in sdb, so in fact it should allow degraded mount.

This patchset will introduce a new per-chunk degradable check for
btrfs, allow above case to succeed, and it's quite small anyway.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ copied text from cover letter with more details about the problem being
  solved ]
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:02 +02:00
Liu Bo
0d1e0bead6 Btrfs: report errors when checksum is not found
When btrfs fails the checksum check, it'll fill the whole page with
"1".

However, if %csum_expected is 0 (which means there is no checksum), then
for some unknown reason, we just pretend that the read is correct, so
userspace would be confused about the dilemma that read is successful but
getting a page with all content being "1".

This can happen due to a bug in btrfs-convert.

This fixes it by always returning errors if checksum doesn't match.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:02 +02:00
Nikolay Borisov
69f03f137a btrfs: Prevent possible ERR_PTR() dereference
In btrfs_full_stripe_len/btrfs_is_parity_mirror we have similar code which
gets the chunk map for a particular range via get_chunk_map. However,
get_chunk_map can return an ERR_PTR value and while the 2 callers do catch
this with a WARN_ON they then proceed to indiscriminately dereference the
extent map. This of course leads to a crash. Fix the offenders by making the
dereference conditional on IS_ERR.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:02 +02:00
Nikolay Borisov
1174cade81 btrfs: Remove redundant checks from btrfs_alloc_data_chunk_ondemand
Many commits ago the data space_info in alloc_data_chunk_ondemand used to be
acquired from the inode. At that point commit
33b4d47f5e ("Btrfs: deal with NULL space info") got introduced to deal with
spurios cases where the space info could be null, following a rebalance.
Nowadays, however, the space info is referenced directly from the btrfs_fs_info
struct which is initialised at filesystem mount time. This makes the null
checks redundant, so remove them.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:02 +02:00
Nikolay Borisov
7bdd6277e0 btrfs: Remove redundant argument of flush_space
All callers of flush_space pass the same number for orig/num_bytes
arguments. Let's remove one of the numbers and also modify the trace
point to show only a single number - bytes requested.

Seems that last point where the two parameters were treated differently
is before the ticketed enospc rework.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:01 +02:00
Aleksa Sarai
6c6b5a39c4 btrfs: resume qgroup rescan on rw remount
Several distributions mount the "proper root" as ro during initrd and
then remount it as rw before pivot_root(2). Thus, if a rescan had been
aborted by a previous shutdown, the rescan would never be resumed.

This issue would manifest itself as several btrfs ioctl(2)s causing the
entire machine to hang when btrfs_qgroup_wait_for_completion was hit
(due to the fs_info->qgroup_rescan_running flag being set but the rescan
itself not being resumed). Notably, Docker's btrfs storage driver makes
regular use of BTRFS_QUOTA_CTL_DISABLE and BTRFS_IOC_QUOTA_RESCAN_WAIT
(causing this problem to be manifested on boot for some machines).

Cc: <stable@vger.kernel.org> # v3.11+
Cc: Jeff Mahoney <jeffm@suse.com>
Fixes: b382a324b6 ("Btrfs: fix qgroup rescan resume on mount")
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:01 +02:00
Edmund Nadolski
01747e92a9 btrfs: clean up extraneous computations in add_delayed_refs
Repeating the same computation in multiple places is not
necessary.

Signed-off-by: Edmund Nadolski <enadolski@suse.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:01 +02:00
Edmund Nadolski
3ec4d3238a btrfs: allow backref search checks for shared extents
When called with a struct share_check, find_parent_nodes()
will detect a shared extent and immediately return with
BACKREF_SHARED_FOUND.

Signed-off-by: Edmund Nadolski <enadolski@suse.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:01 +02:00
Edmund Nadolski
9dd14fd696 btrfs: add cond_resched() calls when resolving backrefs
Since backref resolution is CPU-intensive, the cond_resched calls
should help alleviate soft lockup occurences.

Signed-off-by: Edmund Nadolski <enadolski@suse.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:01 +02:00
Jeff Mahoney
00142756e1 btrfs: backref, add tracepoints for prelim_ref insertion and merging
This patch adds a tracepoint event for prelim_ref insertion and
merging.  For each, the ref being inserted or merged and the count
of tree nodes is issued.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:01 +02:00
Jeff Mahoney
6c336b212b btrfs: add a node counter to each of the rbtrees
This patch adds counters to each of the rbtrees so that we can tell
how large they are growing for a given workload.  These counters
will be exported by tracepoints in the next patch.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:01 +02:00
Edmund Nadolski
86d5f99442 btrfs: convert prelimary reference tracking to use rbtrees
It's been known for a while that the use of multiple lists
that are periodically merged was an algorithmic problem within
btrfs.  There are several workloads that don't complete in any
reasonable amount of time (e.g. btrfs/130) and others that cause
soft lockups.

The solution is to use a set of rbtrees that do insertion merging
for both indirect and direct refs, with the former converting
refs into the latter.  The result is a btrfs/130 workload that
used to take several hours now takes about half of that. This
runtime still isn't acceptable and a future patch will address that
by moving the rbtrees higher in the stack so the lookups can be
shared across multiple calls to find_parent_nodes.

Signed-off-by: Edmund Nadolski <enadolski@suse.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:11:55 +02:00
Edmund Nadolski
f6954245d9 btrfs: remove ref_tree implementation from backref.c
Commit afce772e87 ("btrfs: fix check_shared for fiemap ioctl") added
the ref_tree code in backref.c to reduce backref searching for
shared extents under the FIEMAP ioctl. This code will not be
compatible with the upcoming rbtree changes for improved backref
searching, so this patch removes the ref_tree code.  The rbtree
changes will provide the equivalent functionality for FIEMAP.

The above commit also introduced transaction semantics around calls to
btrfs_check_shared() in order to accurately account for delayed refs.
This functionality needs to be retained, so a complete revert of the
above commit is not desirable. This patch therefore removes the
ref_tree portion of the commit as above, however it does not remove
the transaction portion.

Signed-off-by: Edmund Nadolski <enadolski@suse.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 14:19:53 +02:00
Edmund Nadolski
bb739cf08e btrfs: btrfs_check_shared should manage its own transaction
Commit afce772e87 ("btrfs: fix check_shared for fiemap ioctl") added
transaction semantics around calls to btrfs_check_shared() in order to
provide accurate accounting of delayed refs. The transaction management
should be done inside btrfs_check_shared(), so that callers do not need
to manage transactions individually.

Signed-off-by: Edmund Nadolski <enadolski@suse.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 14:19:53 +02:00
Jeff Mahoney
e0c476b128 btrfs: backref, cleanup __ namespace abuse
We typically use __ to indicate a helper routine that shouldn't be
called directly without understanding the proper context required
to do so.  We use static functions to indicate that a function is
private to a particular C file.  The backref code uses static
function and __ prefixes on nearly everything, which makes the code
difficult to read and establishes a pattern for future code that
shouldn't be followed.  This patch drops all the unnecessary prefixes.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 14:19:53 +02:00
Jeff Mahoney
4dae077a83 btrfs: backref, add unode_aux_to_inode_list helper
Replacing the double cast and ternary conditional with a helper makes
the code easier on the eyes.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 14:19:53 +02:00
Jeff Mahoney
73980becae btrfs: backref, constify some arguments
This constifies a few buffers used in the backref code.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 14:19:53 +02:00
Jeff Mahoney
9a35b63728 btrfs: constify tracepoint arguments
Tracepoint arguments are all read-only.  If we mark the arguments
as const, we're able to keep or convert those arguments to const
where appropriate.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 14:19:53 +02:00
Jeff Mahoney
1cbb1f454e btrfs: struct-funcs, constify readers
We have reader helpers for most of the on-disk structures that use
an extent_buffer and pointer as offset into the buffer that are
read-only.  We should mark them as const and, in turn, allow consumers
of these interfaces to mark the buffers const as well.

No impact on code, but serves as documentation that a buffer is intended
not to be modified.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 14:19:53 +02:00
Nikolay Borisov
23d1f73788 btrfs: remove unused sectorsize member
The sectorsize member of btrfs_block_group_cache is unused. So remove it, this
reduces the number of holes in the struct.

With patch:
/* size: 856, cachelines: 14, members: 40 */
/* sum members: 837, holes: 4, sum holes: 19 */
/* bit holes: 1, sum bit holes: 29 bits */
/* last cacheline: 24 bytes */

Without patch:
/* size: 864, cachelines: 14, members: 41 */
/* sum members: 841, holes: 5, sum holes: 23 */
/* bit holes: 1, sum bit holes: 29 bits */
/* last cacheline: 32 bytes */

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 14:19:53 +02:00
Nikolay Borisov
f148ef4d3a btrfs: Be explicit about usage of min()
__btrfs_alloc_chunk contains code which boils down to:

    ndevs = min(ndevs, devs_max)

It's conditional upon devs_max not being 0. However, it cannot really be 0
since it's always set to either BTRFS_MAX_DEVS_SYS_CHUNK or
BTRFS_MAX_DEVS(fs_info->chunk_root). So eliminate the condition check and use
min explicitly. This has no functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 14:19:52 +02:00
Nikolay Borisov
e5600fd6fc btrfs: Use explicit round_down call rather than open-coding it
No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 14:19:52 +02:00
Nikolay Borisov
ebcc9301ea btrfs: convert while loop to list_for_each_entry
No functional changes, just make the loop a bit more readable

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 14:19:52 +02:00
Linus Torvalds
216e4a1def Some more NFS client bugfixes for 4.13
Stable fix:
 - Fix leaking nfs4_ff_ds_version array
 
 Other fixes:
 - Improve TEST_STATEID OLD_STATEID handling to prevent recovery loop
 - Require 64-bit sector_t for pNFS blocklayout to prevent 32-bit compile
 errors
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Merge tag 'nfs-for-4.13-5' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client fixes from Anna Schumaker:
 "A few more NFS client bugfixes from me for rc5.

  Dros has a stable fix for flexfiles to prevent leaking the
  nfs4_ff_ds_version arrays when freeing a layout, Trond fixed a
  potential recovery loop situation with the TEST_STATEID operation, and
  Christoph fixed up the pNFS blocklayout Kconfig options to prevent
  unsafe use with kernels that don't have large block device support.
  Summary:

  Stable fix:
   - fix leaking nfs4_ff_ds_version array

  Other fixes:
   - improve TEST_STATEID OLD_STATEID handling to prevent recovery loop

   - require 64-bit sector_t for pNFS blocklayout to prevent 32-bit
     compile errors"

* tag 'nfs-for-4.13-5' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  pnfs/blocklayout: require 64-bit sector_t
  NFSv4: Ignore NFS4ERR_OLD_STATEID in nfs41_check_open_stateid()
  nfs/flexfiles: fix leak of nfs4_ff_ds_version arrays
2017-08-11 13:54:09 -07:00
Linus Torvalds
2bfc37cdef Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fixes from Miklos Szeredi:
 "Fix a few bugs in fuse"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: set mapping error in writepage_locked when it fails
  fuse: Dont call set_page_dirty_lock() for ITER_BVEC pages for async_dio
  fuse: initialize the flock flag in fuse_file on allocation
2017-08-11 11:20:48 -07:00
Christoph Hellwig
8a9d6e964d pnfs/blocklayout: require 64-bit sector_t
The blocklayout code does not compile cleanly for a 32-bit sector_t,
and also has no reliable checks for devices sizes, which makes it
unsafe to use with a kernel that doesn't support large block devices.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 5c83746a0c ("pnfs/blocklayout: in-kernel GETDEVICEINFO XDR parsing")
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-08-11 14:10:13 -04:00
Jeff Layton
9183976ef1 fuse: set mapping error in writepage_locked when it fails
This ensures that we see errors on fsync when writeback fails.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2017-08-11 11:38:26 +02:00
Mike Rapoport
e86b298beb userfaultfd: replace ENOSPC with ESRCH in case mm has gone during copy/zeropage
When the process exit races with outstanding mcopy_atomic, it would be
better to return ESRCH error.  When such race occurs the process and
it's mm are going away and returning "no such process" to the uffd
monitor seems better fit than ENOSPC.

Link: http://lkml.kernel.org/r/1502111545-32305-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Minchan Kim
b3a81d0841 mm: fix KSM data corruption
Nadav reported KSM can corrupt the user data by the TLB batching
race[1].  That means data user written can be lost.

Quote from Nadav Amit:
 "For this race we need 4 CPUs:

  CPU0: Caches a writable and dirty PTE entry, and uses the stale value
  for write later.

  CPU1: Runs madvise_free on the range that includes the PTE. It would
  clear the dirty-bit. It batches TLB flushes.

  CPU2: Writes 4 to /proc/PID/clear_refs , clearing the PTEs soft-dirty.
  We care about the fact that it clears the PTE write-bit, and of
  course, batches TLB flushes.

  CPU3: Runs KSM. Our purpose is to pass the following test in
  write_protect_page():

	if (pte_write(*pvmw.pte) || pte_dirty(*pvmw.pte) ||
	    (pte_protnone(*pvmw.pte) && pte_savedwrite(*pvmw.pte)))

  Since it will avoid TLB flush. And we want to do it while the PTE is
  stale. Later, and before replacing the page, we would be able to
  change the page.

  Note that all the operations the CPU1-3 perform canhappen in parallel
  since they only acquire mmap_sem for read.

  We start with two identical pages. Everything below regards the same
  page/PTE.

  CPU0        CPU1        CPU2        CPU3
  ----        ----        ----        ----
  Write the same
  value on page

  [cache PTE as
   dirty in TLB]

              MADV_FREE
              pte_mkclean()

                          4 > clear_refs
                          pte_wrprotect()

                                      write_protect_page()
                                      [ success, no flush ]

                                      pages_indentical()
                                      [ ok ]

  Write to page
  different value

  [Ok, using stale
   PTE]

                                      replace_page()

  Later, CPU1, CPU2 and CPU3 would flush the TLB, but that is too late.
  CPU0 already wrote on the page, but KSM ignored this write, and it got
  lost"

In above scenario, MADV_FREE is fixed by changing TLB batching API
including [set|clear]_tlb_flush_pending.  Remained thing is soft-dirty
part.

This patch changes soft-dirty uses TLB batching API instead of
flush_tlb_mm and KSM checks pending TLB flush by using
mm_tlb_flush_pending so that it will flush TLB to avoid data lost if
there are other parallel threads pending TLB flush.

[1] http://lkml.kernel.org/r/BD3A0EBE-ECF4-41D4-87FA-C755EA9AB6BD@gmail.com

Link: http://lkml.kernel.org/r/20170802000818.4760-8-namit@vmware.com
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Nadav Amit <namit@vmware.com>
Reported-by: Nadav Amit <namit@vmware.com>
Tested-by: Nadav Amit <namit@vmware.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Johannes Weiner
d507e2ebd2 mm: fix global NR_SLAB_.*CLAIMABLE counter reads
As Tetsuo points out:
 "Commit 385386cff4 ("mm: vmstat: move slab statistics from zone to
  node counters") broke "Slab:" field of /proc/meminfo . It shows nearly
  0kB"

In addition to /proc/meminfo, this problem also affects the slab
counters OOM/allocation failure info dumps, can cause early -ENOMEM from
overcommit protection, and miscalculate image size requirements during
suspend-to-disk.

This is because the patch in question switched the slab counters from
the zone level to the node level, but forgot to update the global
accessor functions to read the aggregate node data instead of the
aggregate zone data.

Use global_node_page_state() to access the global slab counters.

Fixes: 385386cff4 ("mm: vmstat: move slab statistics from zone to node counters")
Link: http://lkml.kernel.org/r/20170801134256.5400-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Stefan Agner <stefan@agner.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:06 -07:00
Trond Myklebust
c0ca0e5934 NFSv4: Ignore NFS4ERR_OLD_STATEID in nfs41_check_open_stateid()
If the call to TEST_STATEID returns NFS4ERR_OLD_STATEID, then it just
means we raced with other calls to OPEN.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-08-09 13:36:56 -04:00
Weston Andros Adamson
1feb26162b nfs/flexfiles: fix leak of nfs4_ff_ds_version arrays
The client was freeing the nfs4_ff_layout_ds, but not the contained
nfs4_ff_ds_version array.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-08-08 17:18:10 -04:00
Linus Torvalds
1742c0f055 Changes since last update:
- Fix memory leak when issuing discard
 - Fix propagation of the dax inode flag
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Merge tag 'xfs-4.13-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fixes from Darrick Wong:
 "I have a couple more bug fixes for you today:

   - fix memory leak when issuing discard

   - fix propagation of the dax inode flag"

* tag 'xfs-4.13-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: Fix per-inode DAX flag inheritance
  xfs: Fix leak of discard bio
2017-08-07 18:16:22 -07:00
Linus Torvalds
ed66da1104 A large number of ext4 bug fixes and cleanups for v4.13
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 fixes from Ted Ts'o:
 "A large number of ext4 bug fixes and cleanups for v4.13"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix copy paste error in ext4_swap_extents()
  ext4: fix overflow caused by missing cast in ext4_resize_fs()
  ext4, project: expand inode extra size if possible
  ext4: cleanup ext4_expand_extra_isize_ea()
  ext4: restructure ext4_expand_extra_isize
  ext4: fix forgetten xattr lock protection in ext4_expand_extra_isize
  ext4: make xattr inode reads faster
  ext4: inplace xattr block update fails to deduplicate blocks
  ext4: remove unused mode parameter
  ext4: fix warning about stack corruption
  ext4: fix dir_nlink behaviour
  ext4: silence array overflow warning
  ext4: fix SEEK_HOLE/SEEK_DATA for blocksize < pagesize
  ext4: release discard bio after sending discard commands
  ext4: convert swap_inode_data() over to use swap() on most of the fields
  ext4: error should be cleared if ea_inode isn't added to the cache
  ext4: Don't clear SGID when inheriting ACLs
  ext4: preserve i_mode if __ext4_set_acl() fails
  ext4: remove unused metadata accounting variables
  ext4: correct comment references to ext4_ext_direct_IO()
2017-08-06 12:31:17 -07:00
Maninder Singh
4e56201321 ext4: fix copy paste error in ext4_swap_extents()
This bug was found by a static code checker tool for copy paste
problems.

Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-06 01:33:07 -04:00
Jerry Lee
aec51758ce ext4: fix overflow caused by missing cast in ext4_resize_fs()
On a 32-bit platform, the value of n_blcoks_count may be wrong during
the file system is resized to size larger than 2^32 blocks.  This may
caused the superblock being corrupted with zero blocks count.

Fixes: 1c6bd7173d
Signed-off-by: Jerry Lee <jerrylee@qnap.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org # 3.7+
2017-08-06 01:18:31 -04:00
Miao Xie
c03b45b853 ext4, project: expand inode extra size if possible
When upgrading from old format, try to set project id
to old file first time, it will return EOVERFLOW, but if
that file is dirtied(touch etc), changing project id will
be allowed, this might be confusing for users, we could
try to expand @i_extra_isize here too.

Reported-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Wang Shilong <wshilong@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-06 01:00:49 -04:00
Miao Xie
b640b2c51b ext4: cleanup ext4_expand_extra_isize_ea()
Clean up some goto statement, make ext4_expand_extra_isize_ea() clearer.

Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Wang Shilong <wshilong@ddn.com>
2017-08-06 00:55:48 -04:00
Miao Xie
cf0a5e818f ext4: restructure ext4_expand_extra_isize
Current ext4_expand_extra_isize just tries to expand extra isize, if
someone is holding xattr lock or some check fails, it will give up.
So rename its name to ext4_try_to_expand_extra_isize.

Besides that, we clean up unnecessary check and move some relative checks
into it.

Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Wang Shilong <wshilong@ddn.com>
2017-08-06 00:40:01 -04:00
Miao Xie
3b10fdc6d8 ext4: fix forgetten xattr lock protection in ext4_expand_extra_isize
We should avoid the contention between the i_extra_isize update and
the inline data insertion, so move the xattr trylock in front of
i_extra_isize update.

Signed-off-by: Miao Xie <miaoxie@huawei.com>
Reviewed-by: Wang Shilong <wshilong@ddn.com>
2017-08-06 00:27:38 -04:00
Tahsin Erdogan
9699d4f91d ext4: make xattr inode reads faster
ext4_xattr_inode_read() currently reads each block sequentially while
waiting for io operation to complete before moving on to the next
block. This prevents request merging in block layer.

Add a ext4_bread_batch() function that starts reads for all blocks
then optionally waits for them to complete. A similar logic is used
in ext4_find_entry(), so update that code to use the new function.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-06 00:07:01 -04:00
Tahsin Erdogan
ec00022030 ext4: inplace xattr block update fails to deduplicate blocks
When an xattr block has a single reference, block is updated inplace
and it is reinserted to the cache. Later, a cache lookup is performed
to see whether an existing block has the same contents. This cache
lookup will most of the time return the just inserted entry so
deduplication is not achieved.

Running the following test script will produce two xattr blocks which
can be observed in "File ACL: " line of debugfs output:

  mke2fs -b 1024 -I 128 -F -O extent /dev/sdb 1G
  mount /dev/sdb /mnt/sdb

  touch /mnt/sdb/{x,y}

  setfattr -n user.1 -v aaa /mnt/sdb/x
  setfattr -n user.2 -v bbb /mnt/sdb/x

  setfattr -n user.1 -v aaa /mnt/sdb/y
  setfattr -n user.2 -v bbb /mnt/sdb/y

  debugfs -R 'stat x' /dev/sdb | cat
  debugfs -R 'stat y' /dev/sdb | cat

This patch defers the reinsertion to the cache so that we can locate
other blocks with the same contents.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
2017-08-05 22:41:42 -04:00
Tahsin Erdogan
77a2e84d51 ext4: remove unused mode parameter
ext4_alloc_file_blocks() does not use its mode parameter. Remove it.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-05 22:15:45 -04:00
Arnd Bergmann
2df2c3402f ext4: fix warning about stack corruption
After commit 62d1034f53e3 ("fortify: use WARN instead of BUG for now"),
we get a warning about possible stack overflow from a memcpy that
was not strictly bounded to the size of the local variable:

    inlined from 'ext4_mb_seq_groups_show' at fs/ext4/mballoc.c:2322:2:
include/linux/string.h:309:9: error: '__builtin_memcpy': writing between 161 and 1116 bytes into a region of size 160 overflows the destination [-Werror=stringop-overflow=]

We actually had a bug here that would have been found by the warning,
but it was already fixed last year in commit 30a9d7afe7 ("ext4: fix
stack memory corruption with 64k block size").

This replaces the fixed-length structure on the stack with a variable-length
structure, using the correct upper bound that tells the compiler that
everything is really fine here. I also change the loop count to check
for the same upper bound for consistency, but the existing code is
already correct here.

Note that while clang won't allow certain kinds of variable-length arrays
in structures, this particular instance is fine, as the array is at the
end of the structure, and the size is strictly bounded.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-05 21:57:46 -04:00
Andreas Dilger
c741489206 ext4: fix dir_nlink behaviour
The dir_nlink feature has been enabled by default for new ext4
filesystems since e2fsprogs-1.41 in 2008, and was automatically
enabled by the kernel for older ext4 filesystems since the
dir_nlink feature was added with ext4 in kernel 2.6.28+ when
the subdirectory count exceeded EXT4_LINK_MAX-1.

Automatically adding the file system features such as dir_nlink is
generally frowned upon, since it could cause the file system to not be
mountable on older kernel, thus preventing the administrator from
rolling back to an older kernel if necessary.

In this case, the administrator might also want to disable the feature
because glibc's fts_read() function does not correctly optimize
directory traversal for directories that use st_nlinks field of 1 to
indicate that the number of links in the directory are not tracked by
the file system, and could fail to traverse the full directory
hierarchy.  Fortunately, in the past ten years very few users have
complained about incomplete file system traversal by glibc's
fts_read().

This commit also changes ext4_inc_count() to allow i_nlinks to reach
the full EXT4_LINK_MAX links on the parent directory (including "."
and "..") before changing i_links_count to be 1.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196405
Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-05 19:47:34 -04:00
Dan Carpenter
381cebfe72 ext4: silence array overflow warning
I get a static checker warning:

    fs/ext4/ext4.h:3091 ext4_set_de_type()
    error: buffer overflow 'ext4_type_by_mode' 15 <= 15

It seems unlikely that we would hit this read overflow in real life, but
it's also simple enough to make the array 16 bytes instead of 15.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-05 19:00:31 -04:00
Jan Kara
fcf5ea1099 ext4: fix SEEK_HOLE/SEEK_DATA for blocksize < pagesize
ext4_find_unwritten_pgoff() does not properly handle a situation when
starting index is in the middle of a page and blocksize < pagesize. The
following command shows the bug on filesystem with 1k blocksize:

  xfs_io -f -c "falloc 0 4k" \
            -c "pwrite 1k 1k" \
            -c "pwrite 3k 1k" \
            -c "seek -a -r 0" foo

In this example, neither lseek(fd, 1024, SEEK_HOLE) nor lseek(fd, 2048,
SEEK_DATA) will return the correct result.

Fix the problem by neglecting buffers in a page before starting offset.

Reported-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
CC: stable@vger.kernel.org # 3.8+
2017-08-05 17:43:24 -04:00