Commit Graph

5458 Commits

Author SHA1 Message Date
Brian Foster
9f9bc034b8 xfs: update fork seq counter on data fork changes
The sequence counter in the xfs_ifork structure is only updated on
COW forks. This is because the counter is currently only used to
optimize out repetitive COW fork checks at writeback time.

Tweak the extent code to update the seq counter regardless of the
fork type in preparation for using this counter on data forks as
well.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-02-11 16:07:00 -08:00
Marco Benatto
d519da41e2 xfs: Introduce XFS_PTAG_VERIFIER_ERROR panic mask
Currently we have a few PTAGs in place allowing us to transform a filesystem
error in a BUG() call.  However, we don't have a panic tag for corrupt
metadata, so introduce XFS_PTAG_VERIFIER_ERROR so that the administrator can
use the fs.xfs.panic_mask sysctl knob to convert any error detected by buffer
verifiers into a kernel panic.

Signed-off-by: Marco Benatto <mbenatto@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
[darrick: light editing of commit message]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-02-11 16:07:00 -08:00
YueHaibing
e88db81645 xfs: remove duplicated xfs_defer.h
Remove duplicated include.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-02-11 16:07:00 -08:00
Darrick J. Wong
654805367d xfs: check attribute name validity
Check extended attribute entry names for invalid characters.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:40 -08:00
Darrick J. Wong
e5d7d51b34 xfs: check directory name validity
Check directory entry names for invalid characters.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:40 -08:00
Darrick J. Wong
87c9607df2 xfs: fix off-by-one error in rtbitmap cross-reference
Fix an off-by-one error in the realtime bitmap "is used" cross-reference
helper function if the realtime extent size is a single block.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:40 -08:00
Darrick J. Wong
f8c1d7023e xfs: scrub should flag dir/attr offsets that aren't mappable with xfs_dablk_t
Teach scrub to flag extent maps that exceed the range that can be mapped
with a xfs_dablk_t.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:40 -08:00
Darrick J. Wong
3258cb208c xfs: abort xattr scrub if fatal signals are pending
The extended attribute scrubber should abort the "read all attrs" loop
if there's a fatal signal pending on the process.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:39 -08:00
Darrick J. Wong
f9e63342b8 xfs: consolidate scrub dinode mapping code into a single function
Move all the confusing dinode mapping code that's split between
xchk_iallocbt_check_cluster and xchk_iallocbt_check_cluster_ifree into
the first function so that it's clearer how we find the dinode for a
given inode.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:39 -08:00
Darrick J. Wong
4539b8a780 xfs: scrub big block inode btrees correctly
Teach scrub how to handle the case that there are one or more inobt
records covering a given inode cluster.  This fixes the operation on big
block filesystems (e.g. 64k blocks, 512 byte inodes).

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:39 -08:00
Darrick J. Wong
b9454fe056 xfs: clean up the inode cluster checking in the inobt scrub
The code to check inobt records against inode clusters is a mess of
poorly named variables and unnecessary parameters.  Clean the
unnecessary inode number parameters out of _check_cluster_freemask in
favor of computing them inside the function instead of making the caller
do it.  In xchk_iallocbt_check_cluster, rename the variables to make it
more obvious just what chunk_ino and cluster_ino represent.

Add a tracepoint to make it easier to track each inode cluster as we
scrub it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:39 -08:00
Darrick J. Wong
a1954242fa xfs: hoist inode cluster checks out of loop
Hoist the inode cluster checks out of the inobt record check loop into
a separate function in preparation for refactoring of that loop.  No
functional changes here; that's in the next patch.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:39 -08:00
Darrick J. Wong
22234c62f9 xfs: check inobt record alignment on big block filesystems
On a big block filesystem, there may be multiple inobt records covering
a single inode cluster.  These records obviously won't be aligned to
cluster alignment rules, and they must cover the entire cluster.  Teach
scrub to check for these things.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:39 -08:00
Darrick J. Wong
c050fdfeb5 xfs: check the ir_startino alignment directly
In xchk_iallocbt_rec, check the alignment of ir_startino by converting
the inode cluster block alignment into units of inodes instead of the
other way around (converting ir_startino to blocks).  This prevents us
from tripping over off-by-one errors in ir_startino which are obscured
by the inode -> block conversion.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:38 -08:00
Darrick J. Wong
435dcf0787 xfs: never try to scrub more than 64 inodes per inobt record
Make sure we never check more than XFS_INODES_PER_CHUNK inodes for any
given inobt record since there can be more than one inobt record mapped
to an inode cluster.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:38 -08:00
Darrick J. Wong
add46b3b02 xfs: set buffer ops when repair probes for btree type
In xrep_findroot_block, we work out the btree type and correctness of a
given block by calling different btree verifiers on root block
candidates.  However, we leave the NULL b_ops while ->verify_read
validates the block, which means that if the verifier calls
xfs_buf_verifier_error it'll crash on the null b_ops.  Fix it to set
b_ops before calling the verifier and unsetting it if the verifier
fails.

Furthermore, improve the documentation around xfs_buf_ensure_ops, which
is the function that is responsible for cleaning up the b_ops state of
buffers that go through xrep_findroot_block but don't match anything.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-03 14:03:59 -08:00
Brian Foster
465fa17f4a xfs: end sync buffer I/O properly on shutdown error
As of commit e339dd8d8b ("xfs: use sync buffer I/O for sync delwri
queue submission"), the delwri submission code uses sync buffer I/O
for sync delwri I/O. Instead of waiting on async I/O to unlock the
buffer, it uses the underlying sync I/O completion mechanism.

If delwri buffer submission fails due to a shutdown scenario, an
error is set on the buffer and buffer completion never occurs. This
can cause xfs_buf_delwri_submit() to deadlock waiting on a
completion event.

We could check the error state before waiting on such buffers, but
that doesn't serialize against the case of an error set via a racing
I/O completion. Instead, invoke I/O completion in the shutdown case
regardless of buffer I/O type.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-02-03 14:03:06 -08:00
Brian Foster
aa6ee4ab69 xfs: eof trim writeback mapping as soon as it is cached
The cached writeback mapping is EOF trimmed to try and avoid races
between post-eof block management and writeback that result in
sending cached data to a stale location. The cached mapping is
currently trimmed on the validation check, which leaves a race
window between the time the mapping is cached and when it is trimmed
against the current inode size.

For example, if a new mapping is cached by delalloc conversion on a
blocksize == page size fs, we could cycle various locks, perform
memory allocations, etc.  in the writeback codepath before the
associated mapping is eventually trimmed to i_size. This leaves
enough time for a post-eof truncate and file append before the
cached mapping is trimmed. The former event essentially invalidates
a range of the cached mapping and the latter bumps the inode size
such the trim on the next writepage event won't trim all of the
invalid blocks. fstest generic/464 reproduces this scenario
occasionally and causes a lost writeback and stale delalloc blocks
warning on inode inactivation.

To work around this problem, trim the cached writeback mapping as
soon as it is cached in addition to on subsequent validation checks.
This is a minor tweak to tighten the race window as much as possible
until a proper invalidation mechanism is available.

Fixes: 40214d128e ("xfs: trim writepage mapping to within eof")
Cc: <stable@vger.kernel.org> # v4.14+
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.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>
2019-02-03 14:02:49 -08:00
Julia Lawall
90be9b86da xfs: xfs_fsops: drop useless LIST_HEAD
Drop LIST_HEAD where the variable it declares is never used.

Commit 0410c3bb2b ("xfs: factor ag btree root block
initialisation") stopped using buffer_list and started using a
buffer list in an aghdr_init_data structure, but the declaration
of buffer_list was not removed.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
identifier x;
@@
- LIST_HEAD(x);
  ... when != x
// </smpl>

Fixes: 0410c3bb2b ("xfs: factor ag btree root block initialisation")
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-29 10:47:58 -08:00
Julia Lawall
89be677b6b xfs: xfs_buf: drop useless LIST_HEAD
Drop LIST_HEAD where the variable it declares has never
been used.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
identifier x;
@@
- LIST_HEAD(x);
  ... when != x
// </smpl>

Fixes: 26f1fe858f ("xfs: reduce lock hold times in buffer writeback")
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-29 10:47:34 -08:00
Omar Sandoval
65eed012d1 xfs: reallocate realtime summary cache on growfs
At mount time, we allocate m_rsum_cache with the number of realtime
bitmap blocks. However, xfs_growfs_rt() can increase the number of
realtime bitmap blocks. Using the cache after this happens may access
out of the bounds of the cache. Fix it by reallocating the cache in this
case.

Fixes: 355e353213 ("xfs: cache minimum realtime summary level")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-21 18:45:18 -08:00
Darrick J. Wong
86d163dbfe xfs: stringify scrub types in ftrace output
Use __print_symbolic to print the scrub type in ftrace output.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2018-12-19 14:02:01 -08:00
Darrick J. Wong
c494213f30 xfs: stringify btree cursor types in ftrace output
Use __print_symbolic to print the btree type in ftrace output.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2018-12-19 14:02:01 -08:00
Darrick J. Wong
0357d21a6c xfs: move XFS_INODE_FORMAT_STR mappings to libxfs
Move XFS_INODE_FORMAT_STR to libxfs so that we don't forget to keep it
updated, and add necessary TRACE_DEFINE_ENUM.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2018-12-19 14:02:01 -08:00
Darrick J. Wong
05c753c4cf xfs: move XFS_AG_BTREE_CMP_FORMAT_STR mappings to libxfs
Move XFS_AG_BTREE_CMP_FORMAT_STR to libxfs so that we don't forget to
keep it updated, and TRACE_DEFINE_ENUM the values while we're at it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2018-12-19 14:02:01 -08:00
Darrick J. Wong
85f8dff00a xfs: fix symbolic enum printing in ftrace output
ftrace's __print_symbolic() has a (very poorly documented) requirement
that any enum values used in the symbol to string translation table be
wrapped in a TRACE_DEFINE_ENUM so that the enum value can be encoded in
the ftrace ring buffer.  Fix this unsatisfied requirement.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2018-12-19 14:02:01 -08:00
Darrick J. Wong
7af8150f99 xfs: fix function pointer type in ftrace format
Use %pS instead of %pF in ftrace strings so that we record the actual
function address instead of the function descriptor.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2018-12-19 14:02:00 -08:00
Nick Bowler
a9d25bde1e xfs: Fix x32 ioctls when cmd numbers differ from ia32.
Several ioctl structs change size between native 32-bit (ia32) and x32
applications, because x32 follows the native 64-bit (amd64) integer
alignment rules and uses 64-bit time_t.  In these instances, the ioctl
number changes so userspace simply gets -ENOTTY.  This scenario can be
handled by simply adding more cases.

Looking at the different ioctls implemented here:

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

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

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

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

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

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

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

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

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

Signed-off-by: Nick Bowler <nbowler@draconx.ca>
Fixes: 0facef7fb0 ("xfs: in _attrlist_by_handle, copy the cursor back to userspace")
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-18 10:55:20 -08:00
Darrick J. Wong
64bafd2f1e xfs: require both realtime inodes to mount
Since mkfs always formats the filesystem with the realtime bitmap and
summary inodes immediately after the root directory, we should expect
that both of them are present and loadable, even if there isn't a
realtime volume attached.  There's no reason to skip this if rbmino ==
NULLFSINO; in fact, this causes an immediate crash if the there /is/ a
realtime volume and someone writes to it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
2018-12-13 12:03:45 -08:00
Omar Sandoval
355e353213 xfs: cache minimum realtime summary level
The realtime summary is a two-dimensional array on disk, effectively:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-12-12 08:46:19 -08:00
Eric Sandeen
7d048df4e9 xfs: fix inverted return from xfs_btree_sblock_verify_crc
xfs_btree_sblock_verify_crc is a bool so should not be returning
a failaddr_t; worse, if xfs_log_check_lsn fails it returns
__this_address which looks like a boolean true (i.e. success)
to the caller.

(interestingly xfs_btree_lblock_verify_crc doesn't have the issue)

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

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

Fixes: e53c4b598 ("xfs: ensure post-EOF zeroing happens after zeroing part of a file")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-12-04 08:50:49 -08:00
Ye Yin
de7243057e fs/xfs: fix f_ffree value for statfs when project quota is set
When project is set, we should use inode limit minus the used count

Signed-off-by: Ye Yin <dbyin@tencent.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-11-26 15:01:37 -08:00
Dave Chinner
9230a0b65b xfs: delalloc -> unwritten COW fork allocation can go wrong
Long saga. There have been days spent following this through dead end
after dead end in multi-GB event traces. This morning, after writing
a trace-cmd wrapper that enabled me to be more selective about XFS
trace points, I discovered that I could get just enough essential
tracepoints enabled that there was a 50:50 chance the fsx config
would fail at ~115k ops. If it didn't fail at op 115547, I stopped
fsx at op 115548 anyway.

That gave me two traces - one where the problem manifested, and one
where it didn't. After refining the traces to have the necessary
information, I found that in the failing case there was a real
extent in the COW fork compared to an unwritten extent in the
working case.

Walking back through the two traces to the point where the CWO fork
extents actually diverged, I found that the bad case had an extra
unwritten extent in it. This is likely because the bug it led me to
had triggered multiple times in those 115k ops, leaving stray
COW extents around. What I saw was a COW delalloc conversion to an
unwritten extent (as they should always be through
xfs_iomap_write_allocate()) resulted in a /written extent/:

xfs_writepage:        dev 259:0 ino 0x83 pgoff 0x17000 size 0x79a00 offset 0 length 0
xfs_iext_remove:      dev 259:0 ino 0x83 state RC|LF|RF|COW cur 0xffff888247b899c0/2 offset 32 block 152 count 20 flag 1 caller xfs_bmap_add_extent_delay_real
xfs_bmap_pre_update:  dev 259:0 ino 0x83 state RC|LF|RF|COW cur 0xffff888247b899c0/1 offset 1 block 4503599627239429 count 31 flag 0 caller xfs_bmap_add_extent_delay_real
xfs_bmap_post_update: dev 259:0 ino 0x83 state RC|LF|RF|COW cur 0xffff888247b899c0/1 offset 1 block 121 count 51 flag 0 caller xfs_bmap_add_ex

Basically, Cow fork before:

	0 1            32          52
	+H+DDDDDDDDDDDD+UUUUUUUUUUU+
	   PREV		RIGHT

COW delalloc conversion allocates:

	  1	       32
	  +uuuuuuuuuuuu+
	  NEW

And the result according to the xfs_bmap_post_update trace was:

	0 1            32          52
	+H+wwwwwwwwwwwwwwwwwwwwwwww+
	   PREV

Which is clearly wrong - it should be a merged unwritten extent,
not an unwritten extent.

That lead me to look at the LEFT_FILLING|RIGHT_FILLING|RIGHT_CONTIG
case in xfs_bmap_add_extent_delay_real(), and sure enough, there's
the bug.

It takes the old delalloc extent (PREV) and adds the length of the
RIGHT extent to it, takes the start block from NEW, removes the
RIGHT extent and then updates PREV with the new extent.

What it fails to do is update PREV.br_state. For delalloc, this is
always XFS_EXT_NORM, while in this case we are converting the
delayed allocation to unwritten, so it needs to be updated to
XFS_EXT_UNWRITTEN. This LF|RF|RC case does not do this, and so
the resultant extent is always written.

And that's the bug I've been chasing for a week - a bmap btree bug,
not a reflink/dedupe/copy_file_range bug, but a BMBT bug introduced
with the recent in core extent tree scalability enhancements.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-11-21 10:10:53 -08:00
Dave Chinner
2c307174ab xfs: flush removing page cache in xfs_reflink_remap_prep
On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN        from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff  (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff    (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE    0x5da00 thru 0x651ff        (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff      (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-11-21 10:10:53 -08:00
Dave Chinner
7f9f71be84 xfs: extent shifting doesn't fully invalidate page cache
The extent shifting code uses a flush and invalidate mechainsm prior
to shifting extents around. This is similar to what
xfs_free_file_space() does, but it doesn't take into account things
like page cache vs block size differences, and it will fail if there
is a page that it currently busy.

xfs_flush_unmap_range() handles all of these cases, so just convert
xfs_prepare_shift() to us that mechanism rather than having it's own
special sauce.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-11-20 10:36:19 -08:00