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65 commits

Author SHA1 Message Date
Jan Kara
c184f855c4 xfs: Fix uninitialized return value in xfs_alloc_fix_freelist()
xfs_alloc_fix_freelist() can sometimes jump to out_agbp_relse
without ever setting value of 'error' variable which is then
returned. This can happen e.g. when pag->pagf_init is set but AG is
for metadata and we want to allocate user data.

Fix the problem by initializing 'error' to 0, which is the desired
return value when we decide to skip this group.

CC: xfs@oss.sgi.com
Coverity-id: 1309714
Signed-off-by: Jan Kara <jack@suse.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-25 10:05:13 +10:00
Eric Sandeen
ce748eaa65 xfs: create new metadata UUID field and incompat flag
This adds a new superblock field, sb_meta_uuid.  If set, along with
a new incompat flag, the code will use that field on a V5 filesystem
to compare to metadata UUIDs, which allows us to change the user-
visible UUID at will.  Userspace handles the setting and clearing
of the incompat flag as appropriate, as the UUID gets changed; i.e.
setting the user-visible UUID back to the original UUID (as stored in
the new field) will remove the incompatible feature flag.

If the incompat flag is not set, this copies the user-visible UUID into
into the meta_uuid slot in memory when the superblock is read from disk;
the meta_uuid field is not written back to disk in this case.

The remainder of this patch simply switches verifiers, initializers,
etc to use the new sb_meta_uuid field.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-07-29 11:53:31 +10:00
Dave Chinner
3d238b7e0e Merge branch 'xfs-freelist-cleanup' into for-next 2015-06-23 08:48:43 +10:00
Dave Chinner
496817b4be xfs: clean up XFS_MIN_FREELIST macros
We no longer calculate the minimum freelist size from the on-disk
AGF, so we don't need the macros used for this. That means the
nested macros can be cleaned up, and turn this into an actual
function so the logic is clear and concise. This will make it much
easier to add support for the rmap btree when the time comes.

This also gets rid of the XFS_AG_MAXLEVELS macro used by these
freelist macros as it is simply a wrapper around a single variable.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-22 10:13:30 +10:00
Dave Chinner
396503fc83 xfs: sanitise error handling in xfs_alloc_fix_freelist
The error handling is currently an inconsistent mess as every error
condition handles return values and releasing buffers individually.
Clean this up by using gotos and a sane error label stack.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-22 10:13:19 +10:00
Dave Chinner
72d552854b xfs: factor out free space extent length check
The longest extent length checks in xfs_alloc_fix_freelist() are now
essentially identical. Factor them out into a helper function, so we
know they are checking exactly the same thing before and after we
lock the AGF.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-22 10:04:42 +10:00
Dave Chinner
50adbcb4c4 xfs: xfs_alloc_fix_freelist() can use incore perag structures
At the moment, xfs_alloc_fix_freelist() uses a mix of per-ag based
access and agf buffer  based access to freelist and space usage
information. However, once the AGF buffer is locked inside this
function, it is guaranteed that both the in-memory and on-disk
values are identical. xfs_alloc_fix_freelist() doesn't modify the
values in the structures directly, so it is a read-only user of the
infomration, and hence can use the per-ag structure exclusively for
determining what it should do.

This opens up an avenue for cleaning up a lot of duplicated logic
whose only difference is the structure it gets the data from, and in
doing so removes a lot of needless byte swapping overhead when
fixing up the free list.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-22 10:04:31 +10:00
Brian Foster
bfe46d4eb9 xfs: support min/max agbno args in block allocator
The block allocator supports various arguments to tweak block allocation
behavior and set allocation requirements. The sparse inode chunk feature
introduces a new requirement not supported by the current arguments.
Sparse inode allocations must convert or merge into an inode record that
describes a fixed length chunk (64 inodes x inodesize). Full inode chunk
allocations by definition always result in valid inode records. Sparse
chunk allocations are smaller and the associated records can refer to
blocks not owned by the inode chunk. This model can result in invalid
inode records in certain cases.

For example, if a sparse allocation occurs near the start of an AG, the
aligned inode record for that chunk might refer to agbno 0. If an
allocation occurs towards the end of the AG and the AG size is not
aligned, the inode record could refer to blocks beyond the end of the
AG. While neither of these scenarios directly result in corruption, they
both insert invalid inode records and at minimum cause repair to
complain, are unlikely to merge into full chunks over time and set land
mines for other areas of code.

To guarantee sparse inode chunk allocation creates valid inode records,
support the ability to specify an agbno range limit for
XFS_ALLOCTYPE_NEAR_BNO block allocations. The min/max agbno's are
specified in the allocation arguments and limit the block allocation
algorithms to that range. The starting 'agbno' hint is clamped to the
range if the specified agbno is out of range. If no sufficient extent is
available within the range, the allocation fails. For backwards
compatibility, the min/max fields can be initialized to 0 to disable
range limiting (e.g., equivalent to min=0,max=agsize).

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-05-29 08:53:00 +10:00
Dave Chinner
3790a8cd8a xfs: xfs_alloc_fix_minleft can underflow near ENOSPC
Test generic/224 is failing with a corruption being detected on one
of Michael's test boxes.  Debug that Michael added is indicating
that the minleft trimming is resulting in an underflow:

.....
 before fixup:              rlen          1  args->len          0
 after xfs_alloc_fix_len  : rlen          1  args->len          1
 before goto out_nominleft: rlen          1  args->len          0
 before fixup:              rlen          1  args->len          0
 after xfs_alloc_fix_len  : rlen          1  args->len          1
 after fixup:               rlen          1  args->len          1
 before fixup:              rlen          1  args->len          0
 after xfs_alloc_fix_len  : rlen          1  args->len          1
 after fixup:               rlen 4294967295  args->len 4294967295
 XFS: Assertion failed: fs_is_ok, file: fs/xfs/libxfs/xfs_alloc.c, line: 1424

The "goto out_nominleft:" indicates that we are getting close to
ENOSPC in the AG, and a couple of allocations later we underflow
and the corruption check fires in xfs_alloc_ag_vextent_size().

The issue is that the extent length fixups comaprisons are done
with variables of xfs_extlen_t types. These are unsigned so an
underflow looks like a really big value and hence is not detected
as being smaller than the minimum length allowed for the extent.
Hence the corruption check fires as it is noticing that the returned
length is longer than the original extent length passed in.

This can be easily fixed by ensuring we do the underflow test on
signed values, the same way xfs_alloc_fix_len() prevents underflow.
So we realise in future that these casts prevent underflows from
going undetected, add comments to the code indicating this.

Reported-by: Michael L. Semon <mlsemon35@gmail.com>
Tested-by: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-24 10:16:04 +11:00
Eric Sandeen
5fb5aeeeb6 xfs: pass mp to XFS_WANT_CORRUPTED_RETURN
Today, if we hit an XFS_WANT_CORRUPTED_RETURN we don't print any
information about which filesystem hit it.  Passing in the mp allows
us to print the filesystem (device) name, which is a pretty critical
piece of information.

Tested by running fsfuzzer 'til I hit some.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 22:39:13 +11:00
Eric Sandeen
c29aad4115 xfs: pass mp to XFS_WANT_CORRUPTED_GOTO
Today, if we hit an XFS_WANT_CORRUPTED_GOTO we don't print any
information about which filesystem hit it.  Passing in the mp allows
us to print the filesystem (device) name, which is a pretty critical
piece of information.

Tested by running fsfuzzer 'til I hit some.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 22:39:08 +11:00
Christoph Hellwig
4fb6e8ade2 xfs: merge xfs_ag.h into xfs_format.h
More on-disk format consolidation.  A few declarations that weren't on-disk
format related move into better suitable spots.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-28 14:25:04 +11:00
Eric Sandeen
e1b05723ed xfs: add a few more verifier tests
These were exposed by fsfuzzer runs; without them we fail
in various exciting and sometimes convoluted ways when we
encounter disk corruption.

Without the MAXLEVELS tests we tend to walk off the end of
an array in a loop like this:

        for (i = 0; i < cur->bc_nlevels; i++) {
                if (cur->bc_bufs[i])

Without the dirblklog test we try to allocate more memory
than we could possibly hope for and loop forever:

xfs_dabuf_map()
	nfsb = mp->m_dir_geo->fsbcount;
	irecs = kmem_zalloc(sizeof(irec) * nfsb, KM_SLEEP...

As for the logbsize check, that's the convoluted one.

If logbsize is specified at mount time, it's sanitized
in xfs_parseargs; in particular it makes sure that it's
not > XLOG_MAX_RECORD_BSIZE.

If not specified at mount time, it comes from the superblock
via sb_logsunit; this is limited to 256k at mkfs time as well;
it's copied into m_logbsize in xfs_finish_flags().

However, if for some reason the on-disk value is corrupt and
too large, nothing catches it.  It's a circuitous path, but
that size eventually finds its way to places that make the kernel
very unhappy, leading to oopses in xlog_pack_data() because we
use the size as an index into iclog->ic_data, but the array
is not necessarily that big.

Anyway - bounds checking when we read from disk is a good thing!

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-09 11:47:24 +10:00
Dave Chinner
2451337dd0 xfs: global error sign conversion
Convert all the errors the core XFs code to negative error signs
like the rest of the kernel and remove all the sign conversion we
do in the interface layers.

Errors for conversion (and comparison) found via searches like:

$ git grep " E" fs/xfs
$ git grep "return E" fs/xfs
$ git grep " E[A-Z].*;$" fs/xfs

Negation points found via searches like:

$ git grep "= -[a-z,A-Z]" fs/xfs
$ git grep "return -[a-z,A-D,F-Z]" fs/xfs
$ git grep " -[a-z].*;" fs/xfs

[ with some bits I missed from Brian Foster ]

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-25 14:58:08 +10:00
Dave Chinner
30f712c9dd libxfs: move source files
Move all the source files that are shared with userspace into
libxfs/. This is done as one big chunk simpy to get it done
quickly

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-25 14:57:53 +10:00
Renamed from fs/xfs/xfs_alloc.c (Browse further)