5346 Commits

Author SHA1 Message Date
Eric Sandeen
89c2e71123 xfs: use xfs_trans_getsb in xfs_sync_sb_buf
Use xfs_trans_getsb rather than reaching right in for
mp->m_sb_bp; I think this is more correct, and it facilitates
building this libxfs code in userspace as well.

Signed-off-by: Eric Sandeen <sandeen@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>
2018-06-04 18:25:05 -07:00
Darrick J. Wong
d2e7366542 xfs: don't assert on corrupted unlinked inode list
Use the per-ag inode number verifiers to detect corrupt lists and error
out, instead of using ASSERTs.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 18:25:05 -07:00
Darrick J. Wong
2551a53053 xfs: explicitly pass buffer size to xfs_corruption_error
Explicitly pass the buffer length to xfs_corruption_error() instead of
assuming XFS_CORRUPTION_DUMP_LEN so that we avoid dumping off the end
of the buffer.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 18:25:05 -07:00
Darrick J. Wong
85ae01098c xfs: don't assert when on-disk btree pointers are garbage
Don't ASSERT when we encounter bad on-disk btree pointers in the debug
check functions.  Log the error to leave breadcrumbs and let the upper
layers deal with it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 18:25:05 -07:00
Darrick J. Wong
e63a1008ee xfs: strengthen btree pointer checks before use
Instead of ASSERTing on null btree pointers in xfs_btree_ptr_to_daddr,
use the new block number verifiers to ensure that the btree pointer
doesn't point to any sensitive areas (AG headers, past-EOFS) and return
-EFSCORRUPTED if this is the case.  Remove the ASSERT because on-disk
corruptions shouldn't trigger ASSERTs.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 18:25:05 -07:00
Darrick J. Wong
4cbae4b816 xfs: introduce xfs_btree_debug_check_ptr
Make xfs_btree_check_ptr a non-debug function and introduce a new _debug
version that only runs when #ifdef DEBUG.   This will enable us to reuse
the checking logic with other parts of the btree code.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 18:25:05 -07:00
Darrick J. Wong
e4f45eff86 xfs: check directory bestfree information in the verifier
Create a variant of xfs_dir2_data_freefind that is suitable for use in a
verifier.  Because _freefind is called by the verifier, we simply
duplicate the _freefind function, convert the ASSERTs to return
__this_address, and modify the verifier to call our new function.  Once
we've made it impossible for directory blocks with bad bestfree data to
make it into the filesystem we can remove the DEBUG code from the
regular _freefind function.

Underlying argument: corruption of on-disk metadata should return
-EFSCORRUPTED instead of blowing ASSERTs.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 18:25:04 -07:00
Darrick J. Wong
924cade4df xfs: don't return garbage buffers in xfs_da3_node_read
If we're reading a node in a dir/attr btree and the buffer comes off the
disk with a magic number we don't recognize, don't ASSERT and don't set
a garbage buffer type (0 also triggers ASSERTs).  Instead, report the
corruption, release the buffer, and return -EFSCORRUPTED because that's
what the dabtree is -- corrupt.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 14:45:30 -07:00
Darrick J. Wong
1f5c071d19 xfs: don't ASSERT on short form btree root pointer of zero
Don't ASSERT if the short form btree root pointer is zero.  Now that we
use xfs_verify_agbno to check all short form btree pointers, we'll let
that log the error and pass it to the upper layers.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 14:45:30 -07:00
Darrick J. Wong
eeee0d6a9b xfs: btree lookup shouldn't ASSERT on empty btree nodes
If a btree lookup encounters an empty btree node or an empty btree leaf
on a multi-level btree, that's evidence of a corrupt on-disk btree.
Therefore, we should return -EFSCORRUPTED to the upper levels, not an
ASSERT failure.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 14:45:30 -07:00
Darrick J. Wong
a37f7b127e xfs: xfs_alloc_get_rec should return EFSCORRUPTED for obvious bnobt corruption
Return -EFSCORRUPTED when the bnobt/cntbt return obviously corrupt
values, rather than letting them bounce around in the internal code.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 14:45:30 -07:00
Darrick J. Wong
b3986010ce xfs: remove redundant ASSERT on insufficient bestfree length in _leaf_addname
In xfs_dir2_leaf_addname we ASSERT if the length of the unused space
described by bestfree[0] is less the amount of space we wish to consume.
Immediately after it is a call to xfs_dir2_data_use_free where the
offset parameter is offset of the unused space and the length parameter
is the amount of space we wish to consume.  Both values (and the unused
space pointer) are passed into xfs_dir2_data_check_free, which also
validates that the region of unused space is big enough to cover the
space we wish to consume.  This is effectively the same check that the
ASSERT covers, and since a check failure results in a corruption message
being logged we can remove the ASSERT.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 14:45:29 -07:00
Darrick J. Wong
17ba2cc7b5 xfs: don't assert when reporting on-disk corruption while loading btree
Don't bother ASSERTing when we're already going to log and return the
corruption status.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 14:45:29 -07:00
Darrick J. Wong
aaacdd257f xfs: don't forbid setting dax flag on directories if device doesn't dax
On a directory, the DAX flag is merely a hint that files created in the
directory should have the DAX flag set at creation time.  We don't care
if the underlying device supports DAX or not because directory metadata
are always cached in DRAM.  We don't care if new files get the flag even
if the device doesn't support DAX because we always check for DAX
support before setting the VFS flag (S_DAX).

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 14:45:29 -07:00
Linus Torvalds
b058efc1ac Merge branch 'work.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull dcache lookup cleanups from Al Viro:
 "Cleaning ->lookup() instances up - mostly d_splice_alias() conversions"

* 'work.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (29 commits)
  switch the rest of procfs lookups to d_splice_alias()
  procfs: switch instantiate_t to d_splice_alias()
  don't bother with tid_fd_revalidate() in lookups
  proc_lookupfd_common(): don't bother with instantiate unless the file is open
  procfs: get rid of ancient BS in pid_revalidate() uses
  cifs_lookup(): switch to d_splice_alias()
  cifs_lookup(): cifs_get_inode_...() never returns 0 with *inode left NULL
  9p: unify paths in v9fs_vfs_lookup()
  ncp_lookup(): use d_splice_alias()
  hfsplus: switch to d_splice_alias()
  hfs: don't allow mounting over .../rsrc
  hfs: use d_splice_alias()
  omfs_lookup(): report IO errors, use d_splice_alias()
  orangefs_lookup: simplify
  openpromfs: switch to d_splice_alias()
  xfs_vn_lookup: simplify a bit
  adfs_lookup: do not fail with ENOENT on negatives, use d_splice_alias()
  adfs_lookup_byname: .. *is* taken care of in fs/namei.c
  romfs_lookup: switch to d_splice_alias()
  qnx6_lookup: switch to d_splice_alias()
  ...
2018-06-04 13:46:22 -07:00
Linus Torvalds
cf626b0da7 Merge branch 'hch.procfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull procfs updates from Al Viro:
 "Christoph's proc_create_... cleanups series"

* 'hch.procfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (44 commits)
  xfs, proc: hide unused xfs procfs helpers
  isdn/gigaset: add back gigaset_procinfo assignment
  proc: update SIZEOF_PDE_INLINE_NAME for the new pde fields
  tty: replace ->proc_fops with ->proc_show
  ide: replace ->proc_fops with ->proc_show
  ide: remove ide_driver_proc_write
  isdn: replace ->proc_fops with ->proc_show
  atm: switch to proc_create_seq_private
  atm: simplify procfs code
  bluetooth: switch to proc_create_seq_data
  netfilter/x_tables: switch to proc_create_seq_private
  netfilter/xt_hashlimit: switch to proc_create_{seq,single}_data
  neigh: switch to proc_create_seq_data
  hostap: switch to proc_create_{seq,single}_data
  bonding: switch to proc_create_seq_data
  rtc/proc: switch to proc_create_single_data
  drbd: switch to proc_create_single
  resource: switch to proc_create_seq_data
  staging/rtl8192u: simplify procfs code
  jfs: simplify procfs code
  ...
2018-06-04 10:00:01 -07:00
Dave Chinner
9f96cc958e xfs: verify AGI unlinked list contains valid blocks
The heads of tha AGI unlinked list are only scanned on debug
kernels when the verifier runs. Change that to always scan the heads
and validate that the inode numbers are valid.

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>
2018-06-03 16:12:16 -07:00
Christoph Hellwig
b84e772299 xfs: use iomap_bmap
Switch to the iomap based bmap implementation to get rid of one of the
last users of xfs_get_blocks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
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>
2018-06-01 18:37:33 -07:00
Dave Chinner
16858f7c21 xfs: fix error handling in xfs_refcount_insert()
generic/475 fired an assert failure just after the filesystem was
shut down:

XFS: Assertion failed: fs_is_ok, file: fs/xfs/libxfs/xfs_refcount.c, line: 182
.....
Call Trace:
 xfs_refcount_insert+0x151/0x190
 xfs_refcount_adjust_extents.constprop.11+0x9c/0x470
 xfs_refcount_adjust.constprop.10+0xb0/0x270
 xfs_refcount_finish_one+0x25a/0x420
 xfs_trans_log_finish_refcount_update+0x2a/0x40
 xfs_refcount_update_finish_item+0x35/0xa0
 xfs_defer_finish+0x15e/0x4d0
 xfs_reflink_remap_extent+0x1bc/0x610
 xfs_reflink_remap_blocks+0x6e/0x280
 xfs_reflink_remap_range+0x311/0x530
 vfs_clone_file_range+0x119/0x200
 ....

If xfs_btree_insert() returns an error, the corruption check fires
instead of passing the error back the caller. The corruption check
should be after we've checked for an error, not before, thereby
avoiding assert failures if the filesystem shuts down during a
refcount btree record insert.

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>
2018-06-01 09:00:16 -07:00
Darrick J. Wong
a0e5c435ba xfs: fix xfs_rtalloc_rec units
All the realtime allocation functions deal with space on the rtdev in
units of realtime extents.  However, struct xfs_rtalloc_rec confusingly
uses the word 'block' in the name, even though they're really extents.

Fix the naming problem and fix all the unit handling problems in the two
existing users.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
2018-06-01 09:00:16 -07:00
Darrick J. Wong
8ad560d256 xfs: strengthen rtalloc query range checks
Strengthen the rtalloc range query checks to make sure that the keys do
not run off the end of the realtime device inappropriately.  Note that
the query range functions require units of rt extents, not blocks,
despite the type name.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
2018-06-01 09:00:16 -07:00
Darrick J. Wong
a03f1641c7 xfs: xfs_rtbuf_get should check the bmapi_read results
The xfs_rtbuf_get function should check the block mapping it gets back
from bmapi_read.  If there are no mappings or the mapping isn't a real
extent, we should return -EFSCORRUPTED rather than trying to read a
garbage value.  We also require realtime bitmap blocks to be real,
written allocations.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
2018-06-01 09:00:16 -07:00
Darrick J. Wong
2483113f3d xfs: xfs_rtword_t should be unsigned, not signed
xfs_rtword_t is used for bit manipulations in the realtime bitmap file.
Since we're performing bit shifts with this type, we don't want sign
extension and we don't want to be left shifting negative quantities
because that's undefined behavior.

This also shuts up these UBSAN warnings:
UBSAN: Undefined behaviour in fs/xfs/libxfs/xfs_rtbitmap.c:833:48
signed integer overflow:
-2147483648 - 1 cannot be represented in type 'int'

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
2018-06-01 09:00:16 -07:00
Dave Jiang
80660f2025 dax: change bdev_dax_supported() to support boolean returns
The function return values are confusing with the way the function is
named. We expect a true or false return value but it actually returns
0/-errno.  This makes the code very confusing. Changing the return values
to return a bool where if DAX is supported then return true and no DAX
support returns false.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-31 08:58:34 -07:00
Darrick J. Wong
ba23cba9b3 fs: allow per-device dax status checking for filesystems
Change bdev_dax_supported so it takes a bdev parameter.  This enables
multi-device filesystems like xfs to check that a dax device can work for
the particular filesystem.  Once that's in place, actually fix all the
parts of XFS where we need to be able to distinguish between datadev and
rtdev.

This patch fixes the problem where we screw up the dax support checking
in xfs if the datadev and rtdev have different dax capabilities.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
[rez: Re-added __bdev_dax_supported() for !CONFIG_FS_DAX cases]
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2018-05-31 08:58:33 -07:00
Kent Overstreet
e292d7bc63 xfs: convert to bioset_init()/mempool_init()
Convert XFS to embedded bio sets.

Acked-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-30 15:33:32 -06:00
Darrick J. Wong
d25522f10c xfs: repair superblocks
If one of the backup superblocks is found to differ seriously from
superblock 0, write out a fresh copy from the in-core sb.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-30 08:03:15 -07:00
Darrick J. Wong
7e85bc6c87 xfs: add helpers to attach quotas to inodes
Add a helper routine to attach quota information to inodes that are
about to undergo repair.  If that fails, we need to schedule a
quotacheck for the next mount but allow the corrupted metadata repair to
continue.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-30 08:03:15 -07:00
Darrick J. Wong
04a2b7b254 xfs: recover AG btree roots from rmap data
Add a helper function to help us recover btree roots from the rmap data.
Callers pass in a list of rmap owner codes, buffer ops, and magic
numbers.  We iterate the rmap records looking for owner matches, and
then read the matching blocks to see if the magic number & uuid match.
If so, we then read-verify the block, and if that passes then we retain
a pointer to the block with the highest level, assuming that by the end
of the call we will have found the root.  This will be used to reset the
AGF/AGI btree root fields during their rebuild procedures.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-30 08:03:14 -07:00
Darrick J. Wong
12c6510e2f xfs: add helpers to dispose of old btree blocks after a repair
Now that we've plumbed in the ability to construct a list of dead btree
blocks following a repair, add more helpers to dispose of them.  This is
done by examining the rmapbt -- if the btree was the only owner we can
free the block, otherwise it's crosslinked and we can only remove the
rmapbt record.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-30 08:03:14 -07:00
Darrick J. Wong
64a39d876e xfs: add helpers to collect and sift btree block pointers during repair
Add some helpers to assemble a list of fs block extents.  Generally,
repair functions will iterate the rmapbt to make a list (1) of all
extents owned by the nominal owner of the metadata structure; then they
will iterate all other structures with the same rmap owner to make a
list (2) of active blocks; and finally we have a subtraction function to
subtract all the blocks in (2) from (1), with the result that (1) is now
a list of blocks that were owned by the old btree and must be disposed.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-30 08:03:14 -07:00
Darrick J. Wong
73d6b42aa4 xfs: add helpers to allocate and initialize fresh btree roots
Add a pair of helper functions to allocate and initialize fresh btree
roots.  The repair functions will use these as part of recreating
corrupted metadata.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
2018-05-30 08:03:14 -07:00
Darrick J. Wong
0a9633fa2f xfs: add helpers to deal with transaction allocation and rolling
For repairs, we need to reserve at least as many blocks as we think
we're going to need to rebuild the data structure, and we're going to
need some helpers to roll transactions while maintaining locks on the AG
headers so that other threads cannot wander into the middle of a repair.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
2018-05-30 08:03:14 -07:00
Darrick J. Wong
51863d7dd7 xfs: grab the per-ag structure whenever relevant
Grab and hold the per-AG data across a scrub run whenever relevant.
This helps us avoid repeated trips through rcu and the radix tree
in the repair code.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-30 08:03:14 -07:00
Souptick Joarder
05edd888d1 fs: xfs: Change return type to vm_fault_t
Use new return type vm_fault_t for fault handlers.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-29 10:46:03 -07:00
Darrick J. Wong
2e050e648a xfs: fix inobt magic number check
In commit a6a781a58befcbd467c ("xfs: have buffer verifier functions
report failing address") the bad magic number return was ported
incorrectly.

Fixes: a6a781a58befcbd467ce843af4eaca3906aa1f08
Reported-by: syzbot+08ab33be0178b76851c8@syzkaller.appspotmail.com
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2018-05-29 10:46:03 -07:00
Arnd Bergmann
5ef03dbd91 xfs, proc: hide unused xfs procfs helpers
These two functions now trigger a warning when CONFIG_PROC_FS is disabled:

fs/xfs/xfs_stats.c:128:12: error: 'xqmstat_proc_show' defined but not used [-Werror=unused-function]
 static int xqmstat_proc_show(struct seq_file *m, void *v)
            ^~~~~~~~~~~~~~~~~
fs/xfs/xfs_stats.c:118:12: error: 'xqm_proc_show' defined but not used [-Werror=unused-function]
 static int xqm_proc_show(struct seq_file *m, void *v)
            ^~~~~~~~~~~~~

Previously, they were referenced from an unused 'static const' structure,
which is silently dropped by gcc.

We can address the warning by adding the same #ifdef around them that
hides the reference.

Fixes: 3f3942aca6da ("proc: introduce proc_create_single{,_data}")
Cc: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-25 20:43:08 -04:00
Al Viro
b113a6d3cf xfs_vn_lookup: simplify a bit
have all post-xfs_lookup() branches converge on d_splice_alias()

Cc: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-22 14:27:57 -04:00
Dan Williams
d6dc57e251 xfs, dax: introduce xfs_break_dax_layouts()
xfs_break_dax_layouts(), similar to xfs_break_leased_layouts(), scans
for busy / pinned dax pages and waits for those pages to go idle before
any potential extent unmap operation.

dax_layout_busy_page() handles synchronizing against new page-busy
events (get_user_pages). It invalidates all mappings to trigger the
get_user_pages slow path which will eventually block on the xfs inode
lock held in XFS_MMAPLOCK_EXCL mode. If dax_layout_busy_page() finds a
busy page it returns it for xfs to wait for the page-idle event that
will fire when the page reference count reaches 1 (recall ZONE_DEVICE
pages are idle at count 1, see generic_dax_pagefree()).

While waiting, the XFS_MMAPLOCK_EXCL lock is dropped in order to not
deadlock the process that might be trying to elevate the page count of
more pages before arranging for any of them to go idle. I.e. the typical
case of submitting I/O is that iov_iter_get_pages() elevates the
reference count of all pages in the I/O before starting I/O on the first
page. The process of elevating the reference count of all pages involved
in an I/O may cause faults that need to take XFS_MMAPLOCK_EXCL.

Although XFS_MMAPLOCK_EXCL is dropped while waiting, XFS_IOLOCK_EXCL is
held while sleeping. We need this to prevent starvation of the truncate
path as continuous submission of direct-I/O could starve the truncate
path indefinitely if the lock is dropped.

Cc: Dave Chinner <david@fromorbit.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reported-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-05-22 07:19:08 -07:00
Dan Williams
69eb5fa10e xfs: prepare xfs_break_layouts() for another layout type
When xfs is operating as the back-end of a pNFS block server, it
prevents collisions between local and remote operations by requiring a
lease to be held for remotely accessed blocks. Local filesystem
operations break those leases before writing or mutating the extent map
of the file.

A similar mechanism is needed to prevent operations on pinned dax
mappings, like device-DMA, from colliding with extent unmap operations.

BREAK_WRITE and BREAK_UNMAP are introduced as two distinct levels of
layout breaking.

Layouts are broken in the BREAK_WRITE case to ensure that layout-holders
do not collide with local writes. Additionally, layouts are broken in
the BREAK_UNMAP case to make sure the layout-holder has a consistent
view of the file's extent map. While BREAK_WRITE breaks can be satisfied
be recalling FL_LAYOUT leases, BREAK_UNMAP breaks additionally require
waiting for busy dax-pages to go idle while holding XFS_MMAPLOCK_EXCL.

After this refactoring xfs_break_layouts() becomes the entry point for
coordinating both types of breaks. Finally, xfs_break_leased_layouts()
becomes just the BREAK_WRITE handler.

Note that the unlock tracking is needed in a follow on change. That will
coordinate retrying either break handler until both successfully test
for a lease break while maintaining the lock state.

Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Reported-by: Dave Chinner <david@fromorbit.com>
Reported-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-05-22 07:19:08 -07:00
Dan Williams
c63a8eae63 xfs: prepare xfs_break_layouts() to be called with XFS_MMAPLOCK_EXCL
In preparation for adding coordination between extent unmap operations
and busy dax-pages, update xfs_break_layouts() to permit it to be called
with the mmap lock held. This lock scheme will be required for
coordinating the break of 'dax layouts' (non-idle dax (ZONE_DEVICE)
pages mapped into the file's address space). Breaking dax layouts will
be added to xfs_break_layouts() in a future patch, for now this preps
the unmap call sites to take and hold XFS_MMAPLOCK_EXCL over the call to
xfs_break_layouts().

Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <darrick.wong@oracle.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-05-22 07:19:08 -07:00
Eric Sandeen
f7664b3197 xfs: implement online get/set fs label
The GET ioctl is trivial, just return the current label.

The SET ioctl is more involved:
It transactionally modifies the superblock to write a new filesystem
label to the primary super.

A new variant of xfs_sync_sb then writes the superblock buffer
immediately to disk so that the change is visible from userspace.

It then invalidates any page cache that userspace might have previously
read on the block device so that i.e. blkid can see the change
immediately, and updates all secondary superblocks as userspace relable
does.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
[darrick: use dchinner's new xfs_update_secondary_sbs function]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-16 08:50:16 -07:00
Christoph Hellwig
3f3942aca6 proc: introduce proc_create_single{,_data}
Variants of proc_create{,_data} that directly take a seq_file show
callback and drastically reduces the boilerplate code in the callers.

All trivial callers converted over.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-16 07:23:35 +02:00
Dave Chinner
49dd56f26e xfs: factor the ag length extension code into libxfs
Growfs currently manually codes the extension of the last AG in a
filesytem during the growfs process. Factor that out of the growfs
code and move it into libxfs along with teh rest of the AG header
modification code.

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>
2018-05-15 18:12:51 -07:00
Dave Chinner
b16817b66b xfs: move growfs core to libxfs
So it can be shared with userspace (e.g. mkfs) easily.

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>
2018-05-15 18:12:51 -07:00
Dave Chinner
8125147288 xfs: rework secondary superblock updates in growfs
Right now we wait until we've committed changes to the primary
superblock before we initialise any of the new secondary
superblocks. This means that if we have any write errors for new
secondary superblocks we end up with garbage in place rather than
zeros or even an "in progress" superblock to indicate a grow
operation is being done.

To ensure we can write the secondary superblocks, initialise them
earlier in the same loop that initialises the AG headers. We stamp
the new secondary superblocks here with the old geometry, but set
the "sb_inprogress" field to indicate that updates are being done to
the superblock so they cannot be used.  This will result in the
secondary superblock fields being updated or triggering errors that
will abort the grow before we commit any permanent changes.

This also means we can change the update mechanism of the secondary
superblocks.  We know that we are going to wholly overwrite the
information in the struct xfs_sb in the buffer, so there's no point
reading it from disk. Just allocate an uncached buffer, zero it in
memory, stamp the new superblock structure in it and write it out.
If we fail to write it out, then we'll leave the existing sb (old or
new w/ inprogress) on disk for repair to deal with later.

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>
2018-05-15 18:12:51 -07:00
Dave Chinner
83a7f86e39 xfs: separate secondary sb update in growfs
This happens after all the transactions to update the superblock
occur, and errors need to be handled slightly differently. Seperate
out the code into it's own function, and clean up the error goto
stack in the core growfs code as it is now much simpler.

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>
2018-05-15 18:12:51 -07:00
Dave Chinner
87444b8c26 xfs: make imaxpct changes in growfs separate
When growfs changes the imaxpct value of the filesystem, it runs
through all the "change size" growfs code, whether it needs to or
not. Separate out changing imaxpct into it's own function and
transaction to simplify the rest of the growfs code.

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>
2018-05-15 18:12:51 -07:00
Dave Chinner
532ff647d8 xfs: turn ag header initialisation into a table driven operation
There's still more cookie cutter code in setting up each AG header.
Separate all the variables into a simple structure and iterate a
table of header definitions to initialise everything.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-15 18:12:51 -07:00
Dave Chinner
0410c3bb2b xfs: factor ag btree root block initialisation
Cookie cutter code, easily factored.

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>
2018-05-15 18:12:51 -07:00