Commit Graph

950123 Commits

Author SHA1 Message Date
Darrick J. Wong 27dada070d xfs: change the order in which child and parent defer ops are finished
The defer ops code has been finishing items in the wrong order -- if a
top level defer op creates items A and B, and finishing item A creates
more defer ops A1 and A2, we'll put the new items on the end of the
chain and process them in the order A B A1 A2.  This is kind of weird,
since it's convenient for programmers to be able to think of A and B as
an ordered sequence where all the sub-tasks for A must finish before we
move on to B, e.g. A A1 A2 D.

Right now, our log intent items are not so complex that this matters,
but this will become important for the atomic extent swapping patchset.
In order to maintain correct reference counting of extents, we have to
unmap and remap extents in that order, and we want to complete that work
before moving on to the next range that the user wants to swap.  This
patch fixes defer ops to satsify that requirement.

The primary symptom of the incorrect order was noticed in an early
performance analysis of the atomic extent swap code.  An astonishingly
large number of deferred work items accumulated when userspace requested
an atomic update of two very fragmented files.  The cause of this was
traced to the same ordering bug in the inner loop of
xfs_defer_finish_noroll.

If the ->finish_item method of a deferred operation queues new deferred
operations, those new deferred ops are appended to the tail of the
pending work list.  To illustrate, say that a caller creates a
transaction t0 with four deferred operations D0-D3.  The first thing
defer ops does is roll the transaction to t1, leaving us with:

t1: D0(t0), D1(t0), D2(t0), D3(t0)

Let's say that finishing each of D0-D3 will create two new deferred ops.
After finish D0 and roll, we'll have the following chain:

t2: D1(t0), D2(t0), D3(t0), d4(t1), d5(t1)

d4 and d5 were logged to t1.  Notice that while we're about to start
work on D1, we haven't actually completed all the work implied by D0
being finished.  So far we've been careful (or lucky) to structure the
dfops callers such that D1 doesn't depend on d4 or d5 being finished,
but this is a potential logic bomb.

There's a second problem lurking.  Let's see what happens as we finish
D1-D3:

t3: D2(t0), D3(t0), d4(t1), d5(t1), d6(t2), d7(t2)
t4: D3(t0), d4(t1), d5(t1), d6(t2), d7(t2), d8(t3), d9(t3)
t5: d4(t1), d5(t1), d6(t2), d7(t2), d8(t3), d9(t3), d10(t4), d11(t4)

Let's say that d4-d11 are simple work items that don't queue any other
operations, which means that we can complete each d4 and roll to t6:

t6: d5(t1), d6(t2), d7(t2), d8(t3), d9(t3), d10(t4), d11(t4)
t7: d6(t2), d7(t2), d8(t3), d9(t3), d10(t4), d11(t4)
...
t11: d10(t4), d11(t4)
t12: d11(t4)
<done>

When we try to roll to transaction #12, we're holding defer op d11,
which we logged way back in t4.  This means that the tail of the log is
pinned at t4.  If the log is very small or there are a lot of other
threads updating metadata, this means that we might have wrapped the log
and cannot get roll to t11 because there isn't enough space left before
we'd run into t4.

Let's shift back to the original failure.  I mentioned before that I
discovered this flaw while developing the atomic file update code.  In
that scenario, we have a defer op (D0) that finds a range of file blocks
to remap, creates a handful of new defer ops to do that, and then asks
to be continued with however much work remains.

So, D0 is the original swapext deferred op.  The first thing defer ops
does is rolls to t1:

t1: D0(t0)

We try to finish D0, logging d1 and d2 in the process, but can't get all
the work done.  We log a done item and a new intent item for the work
that D0 still has to do, and roll to t2:

t2: D0'(t1), d1(t1), d2(t1)

We roll and try to finish D0', but still can't get all the work done, so
we log a done item and a new intent item for it, requeue D0 a second
time, and roll to t3:

t3: D0''(t2), d1(t1), d2(t1), d3(t2), d4(t2)

If it takes 48 more rolls to complete D0, then we'll finally dispense
with D0 in t50:

t50: D<fifty primes>(t49), d1(t1), ..., d102(t50)

We then try to roll again to get a chain like this:

t51: d1(t1), d2(t1), ..., d101(t50), d102(t50)
...
t152: d102(t50)
<done>

Notice that in rolling to transaction #51, we're holding on to a log
intent item for d1 that was logged in transaction #1.  This means that
the tail of the log is pinned at t1.  If the log is very small or there
are a lot of other threads updating metadata, this means that we might
have wrapped the log and cannot roll to t51 because there isn't enough
space left before we'd run into t1.  This is of course problem #2 again.

But notice the third problem with this scenario: we have 102 defer ops
tied to this transaction!  Each of these items are backed by pinned
kernel memory, which means that we risk OOM if the chains get too long.

Yikes.  Problem #1 is a subtle logic bomb that could hit someone in the
future; problem #2 applies (rarely) to the current upstream, and problem
#3 applies to work under development.

This is not how incremental deferred operations were supposed to work.
The dfops design of logging in the same transaction an intent-done item
and a new intent item for the work remaining was to make it so that we
only have to juggle enough deferred work items to finish that one small
piece of work.  Deferred log item recovery will find that first
unfinished work item and restart it, no matter how many other intent
items might follow it in the log.  Therefore, it's ok to put the new
intents at the start of the dfops chain.

For the first example, the chains look like this:

t2: d4(t1), d5(t1), D1(t0), D2(t0), D3(t0)
t3: d5(t1), D1(t0), D2(t0), D3(t0)
...
t9: d9(t7), D3(t0)
t10: D3(t0)
t11: d10(t10), d11(t10)
t12: d11(t10)

For the second example, the chains look like this:

t1: D0(t0)
t2: d1(t1), d2(t1), D0'(t1)
t3: d2(t1), D0'(t1)
t4: D0'(t1)
t5: d1(t4), d2(t4), D0''(t4)
...
t148: D0<50 primes>(t147)
t149: d101(t148), d102(t148)
t150: d102(t148)
<done>

This actually sucks more for pinning the log tail (we try to roll to t10
while holding an intent item that was logged in t1) but we've solved
problem #1.  We've also reduced the maximum chain length from:

    sum(all the new items) + nr_original_items

to:

    max(new items that each original item creates) + nr_original_items

This solves problem #3 by sharply reducing the number of defer ops that
can be attached to a transaction at any given time.  The change makes
the problem of log tail pinning worse, but is improvement we need to
solve problem #2.  Actually solving #2, however, is left to the next
patch.

Note that a subsequent analysis of some hard-to-trigger reflink and COW
livelocks on extremely fragmented filesystems (or systems running a lot
of IO threads) showed the same symptoms -- uncomfortably large numbers
of incore deferred work items and occasional stalls in the transaction
grant code while waiting for log reservations.  I think this patch and
the next one will also solve these problems.

As originally written, the code used list_splice_tail_init instead of
list_splice_init, so change that, and leave a short comment explaining
our actions.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-10-07 08:40:28 -07:00
Darrick J. Wong ff4ab5e02a xfs: fix an incore inode UAF in xfs_bui_recover
In xfs_bui_item_recover, there exists a use-after-free bug with regards
to the inode that is involved in the bmap replay operation.  If the
mapping operation does not complete, we call xfs_bmap_unmap_extent to
create a deferred op to finish the unmapping work, and we retain a
pointer to the incore inode.

Unfortunately, the very next thing we do is commit the transaction and
drop the inode.  If reclaim tears down the inode before we try to finish
the defer ops, we dereference garbage and blow up.  Therefore, create a
way to join inodes to the defer ops freezer so that we can maintain the
xfs_inode reference until we're done with the inode.

Note: This imposes the requirement that there be enough memory to keep
every incore inode in memory throughout recovery.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-10-07 08:40:28 -07:00
Darrick J. Wong 64a3f3315b xfs: clean up xfs_bui_item_recover iget/trans_alloc/ilock ordering
In most places in XFS, we have a specific order in which we gather
resources: grab the inode, allocate a transaction, then lock the inode.
xfs_bui_item_recover doesn't do it in that order, so fix it to be more
consistent.  This also makes the error bailout code a bit less weird.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-10-07 08:40:28 -07:00
Darrick J. Wong 919522e89f xfs: clean up bmap intent item recovery checking
The bmap intent item checking code in xfs_bui_item_recover is spread all
over the function.  We should check the recovered log item at the top
before we allocate any resources or do anything else, so do that.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-10-07 08:40:28 -07:00
Darrick J. Wong 929b92f640 xfs: xfs_defer_capture should absorb remaining transaction reservation
When xfs_defer_capture extracts the deferred ops and transaction state
from a transaction, it should record the transaction reservation type
from the old transaction so that when we continue the dfops chain, we
still use the same reservation parameters.

Doing this means that the log item recovery functions get to determine
the transaction reservation instead of abusing tr_itruncate in yet
another part of xfs.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-10-07 08:40:28 -07:00
Darrick J. Wong 4f9a60c480 xfs: xfs_defer_capture should absorb remaining block reservations
When xfs_defer_capture extracts the deferred ops and transaction state
from a transaction, it should record the remaining block reservations so
that when we continue the dfops chain, we can reserve the same number of
blocks to use.  We capture the reservations for both data and realtime
volumes.

This adds the requirement that every log intent item recovery function
must be careful to reserve enough blocks to handle both itself and all
defer ops that it can queue.  On the other hand, this enables us to do
away with the handwaving block estimation nonsense that was going on in
xlog_finish_defer_ops.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-10-07 08:40:28 -07:00
Darrick J. Wong e6fff81e48 xfs: proper replay of deferred ops queued during log recovery
When we replay unfinished intent items that have been recovered from the
log, it's possible that the replay will cause the creation of more
deferred work items.  As outlined in commit 509955823c ("xfs: log
recovery should replay deferred ops in order"), later work items have an
implicit ordering dependency on earlier work items.  Therefore, recovery
must replay the items (both recovered and created) in the same order
that they would have been during normal operation.

For log recovery, we enforce this ordering by using an empty transaction
to collect deferred ops that get created in the process of recovering a
log intent item to prevent them from being committed before the rest of
the recovered intent items.  After we finish committing all the
recovered log items, we allocate a transaction with an enormous block
reservation, splice our huge list of created deferred ops into that
transaction, and commit it, thereby finishing all those ops.

This is /really/ hokey -- it's the one place in XFS where we allow
nested transactions; the splicing of the defer ops list is is inelegant
and has to be done twice per recovery function; and the broken way we
handle inode pointers and block reservations cause subtle use-after-free
and allocator problems that will be fixed by this patch and the two
patches after it.

Therefore, replace the hokey empty transaction with a structure designed
to capture each chain of deferred ops that are created as part of
recovering a single unfinished log intent.  Finally, refactor the loop
that replays those chains to do so using one transaction per chain.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-10-07 08:40:28 -07:00
Darrick J. Wong 901219bb25 xfs: remove XFS_LI_RECOVERED
The ->iop_recover method of a log intent item removes the recovered
intent item from the AIL by logging an intent done item and committing
the transaction, so it's superfluous to have this flag check.  Nothing
else uses it, so get rid of the flag entirely.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-10-07 08:40:27 -07:00
Darrick J. Wong b80b29d602 xfs: remove xfs_defer_reset
Remove this one-line helper since the assert is trivially true in one
call site and the rest obscures a bitmask operation.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-10-07 08:40:27 -07:00
Dave Chinner 671459676a xfs: fix finobt btree block recovery ordering
Nathan popped up on #xfs and pointed out that we fail to handle
finobt btree blocks in xlog_recover_get_buf_lsn(). This means they
always fall through the entire magic number matching code to "recover
immediately". Whilst most of the time this is the correct behaviour,
occasionally it will be incorrect and could potentially overwrite
more recent metadata because we don't check the LSN in the on disk
metadata at all.

This bug has been present since the finobt was first introduced, and
is a potential cause of the occasional xfs_iget_check_free_state()
failures we see that indicate that the inode btree state does not
match the on disk inode state.

Fixes: aafc3c2465 ("xfs: support the XFS_BTNUM_FINOBT free inode btree type")
Reported-by: Nathan Scott <nathans@redhat.com>
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>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-09-30 07:28:52 -07:00
Pavel Reichl 3442de9cc3 xfs: remove deprecated sysctl options
These optionr were for Irix compatibility, probably for clustered XFS
clients in a heterogenous cluster which contained both Irix & Linux
machines, so that behavior would be consistent. That doesn't exist anymore
and it's no longer needed.

Signed-off-by: Pavel Reichl <preichl@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: actually state when the sysctls go away]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-09-25 11:34:08 -07:00
Pavel Reichl c23c393eaa xfs: remove deprecated mount options
ikeep/noikeep was a workaround for old DMAPI code which is no longer
relevant.

attr2/noattr2 - is for controlling upgrade behaviour from fixed attribute
fork sizes in the inode (attr1) and dynamic attribute fork sizes (attr2).
mkfs has defaulted to setting attr2 since 2007, hence just about every
XFS filesystem out there in production right now uses attr2.

Signed-off-by: Pavel Reichl <preichl@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: fix minor typos]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-09-25 11:34:08 -07:00
Kaixu Xia c9c626b354 xfs: directly call xfs_generic_create() for ->create() and ->mkdir()
The current create and mkdir handlers both call the xfs_vn_mknod()
which is a wrapper routine around xfs_generic_create() function.
Actually the create and mkdir handlers can directly call
xfs_generic_create() function and reduce the call chain.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-09-25 11:34:08 -07:00
Darrick J. Wong d7884e6e90 xfs: avoid shared rmap operations for attr fork extents
During code review, I noticed that the rmap code uses the (slower)
shared mappings rmap functions for any extent of a reflinked file, even
if those extents are for the attr fork, which doesn't support sharing.
We can speed up rmap a tiny bit by optimizing out this case.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-25 11:34:08 -07:00
Gao Xiang b38e07401e xfs: drop the obsolete comment on filestream locking
Since commit 1c1c6ebcf5 ("xfs: Replace per-ag array with a radix
tree"), there is no m_peraglock anymore, so it's hard to understand
the described situation since per-ag is no longer an array and no
need to reallocate, call xfs_filestream_flush() in growfs.

In addition, the race condition for shrink feature is quite confusing
to me currently as well. Get rid of it instead.

Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-25 11:34:08 -07:00
Kaixu Xia 61ef523051 xfs: code cleanup in xfs_attr_leaf_entsize_{remote,local}
Cleanup the typedef usage, the unnecessary parentheses, the unnecessary
backslash and use the open-coded round_up call in
xfs_attr_leaf_entsize_{remote,local}.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-25 11:34:08 -07:00
Kaixu Xia d6b8fc6c7a xfs: do the assert for all the log done items in xfs_trans_cancel
We should do the assert for all the log intent-done items if they appear
here. This patch detect intent-done items by the fact that their item ops
don't have iop_unpin and iop_push methods and also move the helper
xlog_item_is_intent to xfs_trans.h.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-09-25 11:34:07 -07:00
Kaixu Xia 74af4c1770 xfs: remove the unused parameter id from xfs_qm_dqattach_one
Since we never use the second parameter id, so remove it from
xfs_qm_dqattach_one() function.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-25 11:34:07 -07:00
Kaixu Xia 3feb4ffbf6 xfs: remove the redundant crc feature check in xfs_attr3_rmt_verify
We already check whether the crc feature is enabled before calling
xfs_attr3_rmt_verify(), so remove the redundant feature check in that
function.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-25 11:34:07 -07:00
Kaixu Xia a647d109e0 xfs: fix some comments
Fix the comments to help people understand the code.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
[darrick: fix the indenting problems too]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-25 11:34:07 -07:00
Kaixu Xia 5aff6750d5 xfs: remove the unnecessary xfs_dqid_t type cast
Since the type prid_t and xfs_dqid_t both are uint32_t, seems the
type cast is unnecessary, so remove it.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-25 11:34:07 -07:00
Kaixu Xia 9c0fce4c16 xfs: use the existing type definition for di_projid
We have already defined the project ID type prid_t, so maybe should
use it here.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-25 11:34:07 -07:00
Kaixu Xia c63290e300 xfs: remove the unused SYNCHRONIZE macro
There are no callers of the SYNCHRONIZE() macro, so remove it.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-25 11:34:07 -07:00
Gao Xiang 0c771b99d6 xfs: clean up calculation of LR header blocks
Let's use DIV_ROUND_UP() to calculate log record header
blocks as what did in xlog_get_iclog_buffer_size() and
wrap up a common helper for log recovery.

Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-09-23 09:24:17 -07:00
Gao Xiang f692d09e9c xfs: avoid LR buffer overrun due to crafted h_len
Currently, crafted h_len has been blocked for the log
header of the tail block in commit a70f9fe52d ("xfs:
detect and handle invalid iclog size set by mkfs").

However, each log record could still have crafted h_len
and cause log record buffer overrun. So let's check
h_len vs buffer size for each log record as well.

Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-09-23 08:58:52 -07:00
Darrick J. Wong 384ff09ba2 xfs: don't release log intent items when recovery fails
Nowadays, log recovery will call ->release on the recovered intent items
if recovery fails.  Therefore, it's redundant to release them from
inside the ->recover functions when they're about to return an error.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-23 08:58:52 -07:00
Darrick J. Wong 2dbf872c04 xfs: attach inode to dquot in xfs_bui_item_recover
In the bmap intent item recovery code, we must be careful to attach the
inode to its dquots (if quotas are enabled) so that a change in the
shape of the bmap btree doesn't cause the quota counters to be
incorrect.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-23 08:58:52 -07:00
Darrick J. Wong 93293bcbde xfs: log new intent items created as part of finishing recovered intent items
During a code inspection, I found a serious bug in the log intent item
recovery code when an intent item cannot complete all the work and
decides to requeue itself to get that done.  When this happens, the
item recovery creates a new incore deferred op representing the
remaining work and attaches it to the transaction that it allocated.  At
the end of _item_recover, it moves the entire chain of deferred ops to
the dummy parent_tp that xlog_recover_process_intents passed to it, but
fail to log a new intent item for the remaining work before committing
the transaction for the single unit of work.

xlog_finish_defer_ops logs those new intent items once recovery has
finished dealing with the intent items that it recovered, but this isn't
sufficient.  If the log is forced to disk after a recovered log item
decides to requeue itself and the system goes down before we call
xlog_finish_defer_ops, the second log recovery will never see the new
intent item and therefore has no idea that there was more work to do.
It will finish recovery leaving the filesystem in a corrupted state.

The same logic applies to /any/ deferred ops added during intent item
recovery, not just the one handling the remaining work.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-23 08:58:51 -07:00
Darrick J. Wong e581c9397a xfs: check dabtree node hash values when loading child blocks
When xchk_da_btree_block is loading a non-root dabtree block, we know
that the parent block had to have a (hashval, address) pointer to the
block that we just loaded.  Check that the hashval in the parent matches
the block we just loaded.

This was found by fuzzing nbtree[3].hashval = ones in xfs/394.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-23 08:58:51 -07:00
Darrick J. Wong 8df0fa39bd xfs: don't free rt blocks when we're doing a REMAP bunmapi call
When callers pass XFS_BMAPI_REMAP into xfs_bunmapi, they want the extent
to be unmapped from the given file fork without the extent being freed.
We do this for non-rt files, but we forgot to do this for realtime
files.  So far this isn't a big deal since nobody makes a bunmapi call
to a rt file with the REMAP flag set, but don't leave a logic bomb.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-23 08:58:51 -07:00
Chandan Babu R c54e14d155 xfs: Set xfs_buf's b_ops member when zeroing bitmap/summary files
In xfs_growfs_rt(), we enlarge bitmap and summary files by allocating
new blocks for both files. For each of the new blocks allocated, we
allocate an xfs_buf, zero the payload, log the contents and commit the
transaction. Hence these buffers will eventually find themselves
appended to list at xfs_ail->ail_buf_list.

Later, xfs_growfs_rt() loops across all of the new blocks belonging to
the bitmap inode to set the bitmap values to 1. In doing so, it
allocates a new transaction and invokes the following sequence of
functions,
  - xfs_rtfree_range()
    - xfs_rtmodify_range()
      - xfs_rtbuf_get()
        We pass '&xfs_rtbuf_ops' as the ops pointer to xfs_trans_read_buf().
        - xfs_trans_read_buf()
	  We find the xfs_buf of interest in per-ag hash table, invoke
	  xfs_buf_reverify() which ends up assigning '&xfs_rtbuf_ops' to
	  xfs_buf->b_ops.

On the other hand, if xfs_growfs_rt_alloc() had allocated a few blocks
for the bitmap inode and returned with an error, all the xfs_bufs
corresponding to the new bitmap blocks that have been allocated would
continue to be on xfs_ail->ail_buf_list list without ever having a
non-NULL value assigned to their b_ops members. An AIL flush operation
would then trigger the following warning message to be printed on the
console,

  XFS (loop0): _xfs_buf_ioapply: no buf ops on daddr 0x58 len 8
  00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  00000040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  00000050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  00000060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  00000070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  CPU: 3 PID: 449 Comm: xfsaild/loop0 Not tainted 5.8.0-rc4-chandan-00038-g4d8c2b9de9ab-dirty #37
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
  Call Trace:
   dump_stack+0x57/0x70
   _xfs_buf_ioapply+0x37c/0x3b0
   ? xfs_rw_bdev+0x1e0/0x1e0
   ? xfs_buf_delwri_submit_buffers+0xd4/0x210
   __xfs_buf_submit+0x6d/0x1f0
   xfs_buf_delwri_submit_buffers+0xd4/0x210
   xfsaild+0x2c8/0x9e0
   ? __switch_to_asm+0x42/0x70
   ? xfs_trans_ail_cursor_first+0x80/0x80
   kthread+0xfe/0x140
   ? kthread_park+0x90/0x90
   ret_from_fork+0x22/0x30

This message indicates that the xfs_buf had its b_ops member set to
NULL.

This commit fixes the issue by assigning "&xfs_rtbuf_ops" to b_ops
member of each of the xfs_bufs logged by xfs_growfs_rt_alloc().

Signed-off-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-09-23 08:58:51 -07:00
Chandan Babu R 72cc95132a xfs: Set xfs_buf type flag when growing summary/bitmap files
The following sequence of commands,

  mkfs.xfs -f -m reflink=0 -r rtdev=/dev/loop1,size=10M /dev/loop0
  mount -o rtdev=/dev/loop1 /dev/loop0 /mnt
  xfs_growfs  /mnt

... causes the following call trace to be printed on the console,

XFS: Assertion failed: (bip->bli_flags & XFS_BLI_STALE) || (xfs_blft_from_flags(&bip->__bli_format) > XFS_BLFT_UNKNOWN_BUF && xfs_blft_from_flags(&bip->__bli_format) < XFS_BLFT_MAX_BUF), file: fs/xfs/xfs_buf_item.c, line: 331
Call Trace:
 xfs_buf_item_format+0x632/0x680
 ? kmem_alloc_large+0x29/0x90
 ? kmem_alloc+0x70/0x120
 ? xfs_log_commit_cil+0x132/0x940
 xfs_log_commit_cil+0x26f/0x940
 ? xfs_buf_item_init+0x1ad/0x240
 ? xfs_growfs_rt_alloc+0x1fc/0x280
 __xfs_trans_commit+0xac/0x370
 xfs_growfs_rt_alloc+0x1fc/0x280
 xfs_growfs_rt+0x1a0/0x5e0
 xfs_file_ioctl+0x3fd/0xc70
 ? selinux_file_ioctl+0x174/0x220
 ksys_ioctl+0x87/0xc0
 __x64_sys_ioctl+0x16/0x20
 do_syscall_64+0x3e/0x70
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

This occurs because the buffer being formatted has the value of
XFS_BLFT_UNKNOWN_BUF assigned to the 'type' subfield of
bip->bli_formats->blf_flags.

This commit fixes the issue by assigning one of XFS_BLFT_RTSUMMARY_BUF
and XFS_BLFT_RTBITMAP_BUF to the 'type' subfield of
bip->bli_formats->blf_flags before committing the corresponding
transaction.

Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanrlinux@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-09-21 09:54:29 -07:00
Brian Foster 6dd379c7fa xfs: drop extra transaction roll from inode extent truncate
The inode extent truncate path unmaps extents from the inode block
mapping, finishes deferred ops to free the associated extents and
then explicitly rolls the transaction before processing the next
extent. The latter extent roll is spurious as xfs_defer_finish()
always returns a clean transaction and automatically relogs inodes
attached to the transaction (with lock_flags == 0). This can
unnecessarily increase the number of log ticket regrants that occur
during a long running truncate operation. Remove the explicit
transaction roll.

Signed-off-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>
2020-09-21 09:54:29 -07:00
Darrick J. Wong b96cb835e3 xfs: deprecate the V4 format
The V4 filesystem format contains known weaknesses in the on-disk format
that make metadata verification diffiult.  In addition, the format does
not support dates past 2038 and will not be upgraded to do so.  We
should start the process of retiring the old format to close off attack
surfaces and to encourage users to migrate onto V5.

Therefore, make XFS V4 support a configurable option.  For the first
period it will be default Y in case some distributors want to withdraw
support early; for the second period it will be default N so that anyone
who wishes to continue support can do so; and after that, support will
be removed from the kernel.  Dates for these events have been added to
the upstream kernel.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2020-09-15 20:52:43 -07:00
Darrick J. Wong d4f2c14cc9 xfs: don't propagate RTINHERIT -> REALTIME when there is no rtdev
While running generic/042 with -drtinherit=1 set in MKFS_OPTIONS, I
observed that the kernel will gladly set the realtime flag on any file
created on the loopback filesystem even though that filesystem doesn't
actually have a realtime device attached.  This leads to verifier
failures and doesn't make any sense, so be smarter about this.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-15 20:52:43 -07:00
Darrick J. Wong 8a569d717e xfs: refactor inode flags propagation code
Hoist the code that propagates di_flags and di_flags2 from a parent to a
new child into separate functions.  No functional changes.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-15 20:52:42 -07:00
Darrick J. Wong fe341eb151 xfs: ensure that fpunch, fcollapse, and finsert operations are aligned to rt extent size
Make sure that any fallocate operation that requires the range to be
block-aligned also checks that the range is aligned to the realtime
extent size.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-15 20:52:42 -07:00
Darrick J. Wong 2a6ca4baed xfs: make sure the rt allocator doesn't run off the end
There's an overflow bug in the realtime allocator.  If the rt volume is
large enough to handle a single allocation request that is larger than
the maximum bmap extent length and the rt bitmap ends exactly on a
bitmap block boundary, it's possible that the near allocator will try to
check the freeness of a range that extends past the end of the bitmap.
This fails with a corruption error and shuts down the fs.

Therefore, constrain maxlen so that the range scan cannot run off the
end of the rt bitmap.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-15 20:52:42 -07:00
Zheng Bin 0f4ec0f157 xfs: Remove unneeded semicolon
Fixes coccicheck warning:

fs/xfs/xfs_icache.c:1214:2-3: Unneeded semicolon

Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-09-15 20:52:42 -07:00
Darrick J. Wong 5ffce3cc22 xfs: force the log after remapping a synchronous-writes file
Commit 5833112df7 tried to make it so that a remap operation would
force the log out to disk if the filesystem is mounted with mandatory
synchronous writes.  Unfortunately, that commit failed to handle the
case where the inode or the file descriptor require mandatory
synchronous writes.

Refactor the check into into a helper that will look for all three
conditions, and now we can treat reflink just like any other synchronous
write.

Fixes: 5833112df7 ("xfs: reflink should force the log out if mounted with wsync")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-15 20:52:42 -07:00
Carlos Maiolino e01b7eed5d xfs: Convert xfs_attr_sf macros to inline functions
xfs_attr_sf_totsize() requires access to xfs_inode structure, so, once
xfs_attr_shortform_addname() is its only user, move it to xfs_attr.c
instead of playing with more #includes.

Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-09-15 20:52:42 -07:00
Carlos Maiolino c418dbc980 xfs: Use variable-size array for nameval in xfs_attr_sf_entry
nameval is a variable-size array, so, define it as it, and remove all
the -1 magic number subtractions

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-09-15 20:52:42 -07:00
Carlos Maiolino 47e6cc1000 xfs: Remove typedef xfs_attr_shortform_t
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-09-15 20:52:42 -07:00
Carlos Maiolino 6337c84466 xfs: remove typedef xfs_attr_sf_entry_t
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-09-15 20:52:41 -07:00
Carlos Maiolino 8ca79df85b xfs: Remove kmem_zalloc_large()
This patch aims to replace kmem_zalloc_large() with global kernel memory
API. So, all its callers are now using kvzalloc() directly, so kmalloc()
fallsback to vmalloc() automatically.

Signed-off-by: Carlos Maiolino <cmaiolino@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>
2020-09-15 20:52:41 -07:00
Darrick J. Wong 29887a2271 xfs: enable big timestamps
Enable the big timestamp feature.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-15 20:52:41 -07:00
Darrick J. Wong 06dbf82b04 xfs: trace timestamp limits
Add a couple of tracepoints so that we can check the timestamp limits
being set on inodes and quotas.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-15 20:52:41 -07:00
Darrick J. Wong 4ea1ff3b49 xfs: widen ondisk quota expiration timestamps to handle y2038+
Enable the bigtime feature for quota timers.  We decrease the accuracy
of the timers to ~4s in exchange for being able to set timers up to the
bigtime maximum.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-15 20:52:41 -07:00
Darrick J. Wong f93e5436f0 xfs: widen ondisk inode timestamps to deal with y2038+
Redesign the ondisk inode timestamps to be a simple unsigned 64-bit
counter of nanoseconds since 14 Dec 1901 (i.e. the minimum time in the
32-bit unix time epoch).  This enables us to handle dates up to 2486,
which solves the y2038 problem.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-15 20:52:41 -07:00
Darrick J. Wong 30e0559921 xfs: redefine xfs_ictimestamp_t
Redefine xfs_ictimestamp_t as a uint64_t typedef in preparation for the
bigtime functionality.  Preserve the legacy structure format so that we
can let the compiler take care of the masking and shifting.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-15 20:52:41 -07:00