Commit Graph

753161 Commits

Author SHA1 Message Date
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
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 a6a781a58b ("xfs: have buffer verifier functions
report failing address") the bad magic number return was ported
incorrectly.

Fixes: a6a781a58b
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
Darrick J. Wong
aee9a4a555 fs: clear writeback errors in inode_init_always
In inode_init_always(), we clear the inode mapping flags, which clears
any retained error (AS_EIO, AS_ENOSPC) bits.  Unfortunately, we do not
also clear wb_err, which means that old mapping errors can leak through
to new inodes.

This is crucial for the XFS inode allocation path because we recycle old
in-core inodes and we do not want error state from an old file to leak
into the new file.  This bug was discovered by running generic/036 and
generic/047 in a loop and noticing that the EIOs generated by the
collision of direct and buffered writes in generic/036 would survive the
remount between 036 and 047, and get reported to the fsyncs (on
different files!) in generic/047.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-29 10:46:03 -07:00
Omar Sandoval
19e129618d iomap: don't allow holes in swapfiles
generic_swapfile_activate() doesn't allow holes, so we should be
consistent here. This is also a bit safer: if the user creates a
swapfile with, say, truncate -s $SIZE followed by mkswap, they should
really get an error and not much less swap space than they expected.
swapon(8) will error out before calling swapon(2) if the file has holes,
anyways.

Fixes: 9d93388b0afe ("iomap: add a swapfile activation function")
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-17 07:17:14 -07:00
Omar Sandoval
ec601924df iomap: provide more useful errors for invalid swap files
Currently, for an invalid swap file, we print the same error message
regardless of the reason. This isn't very useful for an admin, who will
likely want to know why exactly they can't use their swap file. So,
let's add specific error messages for each reason, and also move the
bdev check after the flags checks, since the latter are more
fundamental.

Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-16 11:13:34 -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
Eric Sandeen
62750d040b fs: copy BTRFS_IOC_[SG]ET_FSLABEL to vfs
This retains 256 chars as the maximum size through the interface, which
is the btrfs limit and AFAIK exceeds any other filesystem's maximum
label size.

This just copies the ioctl for now and leaves it in place for btrfs
for the time being.  A later patch will allow btrfs to use the new
common ioctl definition, but it may be sent after this is merged.

(Note, Reviewed-by's were originally given for the combined vfs+btrfs
patch, some license taken here.)

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: David Sterba <dsterba@suse.com>
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
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
Dave Chinner
9aebe805a5 xfs: convert growfs AG header init to use buffer lists
We currently write all new AG headers synchronously, which can be
slow for large grow operations. All we really need to do is ensure
all the headers are on disk before we run the growfs transaction, so
convert this to a buffer list and a delayed write operation. We
block waiting for the delayed write buffer submission to complete,
so this will fulfill the requirement to have all the buffers written
correctly before proceeding.

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
cce77bcf48 xfs: factor out AG header initialisation from growfs core
The intialisation of new AG headers is mostly common with the
userspace mkfs code and growfs in the kernel, so start factoring it
out so we can move it to libxfs and use it in both places.

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
879de98ead xfs: one-shot cached buffers
For the new growfs work, we want to ensure that we serialise
secondary superblock updates with other operations (e.g. scrub)
correctly, but we don't want to cache the buffers for long term
reuse. We need cached buffers for serialisation, however.

To solve this, introduce a "oneshot" buffer which will be marshalled
through the cache but then released once the last current reference
goes away. If the buffer is already cached, then we ignore the
"one-shot" behaviour and leave the buffer in the state it was prior
to the one-shot command being run. This means we don't perturb
either the working set or existing cached buffer state by a one-shot
operation.

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
Darrick J. Wong
84d42ea6b6 xfs: implement the metadata repair ioctl flag
Plumb in the pieces necessary to make the "scrub" subfunction of
the scrub ioctl actually work.  This means that we make the IFLAG_REPAIR
flag to the scrub ioctl actually do something, and we add an errortag
knob so that xfstests can force the kernel to rebuild a metadata
structure even if there's nothing wrong with it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-15 18:12:50 -07:00
Darrick J. Wong
718fa74b15 xfs: create tracepoints for online repair
These tracepoints will be used to debug the online repair routines.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-15 18:12:50 -07:00
Darrick J. Wong
7644bd988d xfs: teach xfs_bmapi_remap to accept some bmapi flags
Teach xfs_bmapi_remap how to map in unwritten extent and to skip rmap
updates.  This enables us to rebuild real and unwritten extents from the
rmapbt.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-15 18:12:50 -07:00
Darrick J. Wong
7cf199ba5a xfs: make xfs_bmapi_remapi work with attribute forks
Add a new flags argument to xfs_bmapi_remapi so that we can pass BMAPI
flags into the function.  This enables us to pass in BMAPI_ATTRFORK so
that we can remap things into the attribute fork.  Eventually the
online repair code will use this to rebuild attribute forks, so make it
non-static.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-15 18:12:50 -07:00
Darrick J. Wong
9f3a080ef1 xfs: hoist xfs_scrub_agfl_walk to libxfs as xfs_agfl_walk
This function is basically a generic AGFL block iterator, so promote it
to libxfs ahead of online repair wanting to use it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-15 18:12:50 -07:00
Darrick J. Wong
ddd10c2fe2 xfs: avoid ABBA deadlock when scrubbing parent pointers
In normal operation, the XFS convention is to take an inode's iolock
and then allocate a transaction.  However, when scrubbing parent inodes
this is inverted -- we allocated the transaction to do the scrub, and
now we're trying to grab the parent's iolock.  This can lead to ABBA
deadlocks: some thread grabbed the parent's iolock and is waiting for
space for a transaction while our parent scrubber is sitting on a
transaction trying to get the parent's iolock.

Therefore, convert all iolock attempts to use trylock; if that fails,
they can use the existing mechanisms to back off and try again.

The ABBA deadlock didn't happen with a non-repair scrub because the
transactions don't reserve any space, but repair scrubs require
reservation in order to update metadata.  However, any other concurrent
metadata update (e.g. directory create in the parent) could also induce
this deadlock with the parent scrubber.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-15 18:12:50 -07:00
Darrick J. Wong
517b32b7fa xfs: scrub the data fork of the realtime inodes
The realtime bitmap and summary inodes live on the metadata device, so
we can scrub their data forks with the regular scrubbers.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-15 18:12:50 -07:00
Darrick J. Wong
87d9d609c2 xfs: quota scrub should use bmapbtd scrubber
Replace the quota scrubber's open-coded data fork scrubber with a
redirected call to the bmapbtd scrubber.  This strengthens the quota
scrub to include all the cross-referencing that it does.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-15 18:12:50 -07:00
Darrick J. Wong
8bc763c24d xfs: don't continue scrub if already corrupt
If we've already decided that something is corrupt, we might as well
abort all the loops and exit as quickly as possible.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-15 18:12:50 -07:00
Darrick J. Wong
eac69e1676 xfs: refactor quota limits initialization
Replace all the if (!error) weirdness with helper functions that follow
our regular coding practices, and factor out the ternary expression soup.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-15 17:57:05 -07:00
Darrick J. Wong
689e11c84b xfs: superblock scrub should use short-lived buffers
Secondary superblocks are rarely used, so create a helper to read a
given non-primary AG's superblock and ensure that it won't stick around
hogging memory.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-15 17:57:05 -07:00
Darrick J. Wong
8389f3ffa2 xfs: skip scrub xref if corruption already noted
Don't bother looking for cross-referencing problems if the metadata is
already corrupt or we've already found a cross-referencing problem.
Since we added a helper function for flags testing, convert existing
users to use it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-15 17:57:05 -07:00
Dave Chinner
c9fbd7bbc2 xfs: clear sb->s_fs_info on mount failure
We recently had an oops reported on a 4.14 kernel in
xfs_reclaim_inodes_count() where sb->s_fs_info pointed to garbage
and so the m_perag_tree lookup walked into lala land.

Essentially, the machine was under memory pressure when the mount
was being run, xfs_fs_fill_super() failed after allocating the
xfs_mount and attaching it to sb->s_fs_info. It then cleaned up and
freed the xfs_mount, but the sb->s_fs_info field still pointed to
the freed memory. Hence when the superblock shrinker then ran
it fell off the bad pointer.

With the superblock shrinker problem fixed at teh VFS level, this
stale s_fs_info pointer is still a problem - we use it
unconditionally in ->put_super when the superblock is being torn
down, and hence we can still trip over it after a ->fill_super
call failure. Hence we need to clear s_fs_info if
xfs-fs_fill_super() fails, and we need to check if it's valid in
the places it can potentially be dereferenced after a ->fill_super
failure.

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 17:57:05 -07:00
Dave Chinner
dae5cd8118 xfs: add mount delay debug option
Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[   60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G      D W        4.16.0-rc5-dgc #440
[   60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[   60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[   60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[   60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[   60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[   60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[   60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[   60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[   60.390827] FS:  00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[   60.392253] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[   60.394519] Call Trace:
[   60.395252]  radix_tree_gang_lookup_tag+0xc4/0x130
[   60.395948]  xfs_perag_get_tag+0x37/0xf0
[   60.396522]  xfs_reclaim_inodes_count+0x32/0x40
[   60.397178]  xfs_fs_nr_cached_objects+0x11/0x20
[   60.397837]  super_cache_count+0x35/0xc0
[   60.399159]  shrink_slab.part.66+0xb1/0x370
[   60.400194]  shrink_node+0x7e/0x1a0
[   60.401058]  try_to_free_pages+0x199/0x470
[   60.402081]  __alloc_pages_slowpath+0x3a1/0xd20
[   60.403729]  __alloc_pages_nodemask+0x1c3/0x200
[   60.404941]  cache_grow_begin+0x20b/0x2e0
[   60.406164]  fallback_alloc+0x160/0x200
[   60.407088]  kmem_cache_alloc+0x111/0x4e0
[   60.408038]  ? xfs_buf_rele+0x61/0x430
[   60.408925]  kmem_zone_alloc+0x61/0xe0
[   60.409965]  xfs_inode_alloc+0x24/0x1d0
.....


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 17:57:05 -07:00
Brian Foster
4e529339af xfs: factor out nodiscard helpers
The changes to skip discards of speculative preallocation and
unwritten extents introduced several new wrapper functions through
the bunmapi -> extent free codepath to reduce churn in all of the
associated callers. In several cases, these wrappers simply toggle a
single flag to skip or not skip discards for the resulting blocks.

The explicit _nodiscard() wrappers for such an isolated set of
callers is a bit overkill. Kill off these wrappers and replace with
the calls to the underlying functions in the contexts that need to
control discard behavior. Retain the wrappers that preserve the
original calling conventions to serve the original purpose of
reducing code churn.

This is a refactoring patch and does not change behavior.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-15 17:57:05 -07:00
Darrick J. Wong
67482129cd iomap: add a swapfile activation function
Add a new iomap_swapfile_activate function so that filesystems can
activate swap files without having to use the obsolete and slow bmap
function.  This enables XFS to support fallocate'd swap files and
swap files on realtime devices.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>
2018-05-15 17:57:05 -07:00
Darrick J. Wong
d6b636ebb1 xfs: halt auto-reclamation activities while rebuilding rmap
Rebuilding the reverse-mapping tree requires us to quiesce all inodes in
the filesystem, so we must stop background reclamation of post-EOF and
CoW prealloc blocks.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-15 17:57:05 -07:00
Darrick J. Wong
95eb308caa xfs: add BMAPI_NORMAP flag to perform block remapping without updating rmapbt
Add a new flag, XFS_BMAPI_NORMAP, which will perform file block
remapping without updating the rmapbt.  This will be used by the repair
code to reconstruct bmbts from the rmapbt, in which case we don't want
the rmapbt update.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-15 17:57:05 -07:00
Darrick J. Wong
08daa3ccf5 xfs: add repair helpers for the reference count btree
Add a couple of functions to the refcount btree and generic btree code
that will be used to repair the refcountbt.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-15 17:57:05 -07:00
Darrick J. Wong
4d4f86b49f xfs: add repair helpers for the reverse mapping btree
Add a couple of functions to the reverse mapping btree that will be used
to repair the rmapbt.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-15 17:57:05 -07:00
Darrick J. Wong
7f8f1313d9 xfs: expose various functions to repair code
Expose various helpers that the repair code will want to use.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-15 17:57:05 -07:00
Darrick J. Wong
14861c4740 xfs: add helpers to calculate btree size
Add a bunch of helper functions that calculate the sizes of various
btrees.  These will be used to repair btrees and btree headers.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-15 17:57:05 -07:00
Darrick J. Wong
9d9c90286a xfs: refactor scrub transaction allocation function
Since the transaction allocation helper is about to become more complex,
move it to common.c and remove the redundant parameters.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-15 17:57:05 -07:00