linux-stable.git/fs/gfs2, branch linux-5.6.y

gfs2: Even more gfs2_find_jhead fixes

2020-06-17T14:41:50+00:00

[ Upstream commit 20be493b787cd581c9fffad7fcd6bfbe6af1050c ]

Fix several issues in the previous gfs2_find_jhead fix:
* When updating @blocks_submitted, @block refers to the first block block not
  submitted yet, not the last block submitted, so fix an off-by-one error.
* We want to ensure that @blocks_submitted is far enough ahead of @blocks_read
  to guarantee that there is in-flight I/O.  Otherwise, we'll eventually end up
  waiting for pages that haven't been submitted, yet.
* It's much easier to compare the number of blocks added with the number of
  blocks submitted to limit the maximum bio size.
* Even with bio chaining, we can keep adding blocks until we reach the maximum
  bio size, as long as we stop at a page boundary.  This simplifies the logic.

Signed-off-by: Andreas Gruenbacher 
Reviewed-by: Bob Peterson 
Signed-off-by: Sasha Levin

gfs2: Grab glock reference sooner in gfs2_add_revoke

2020-06-03T06:23:03+00:00

[ Upstream commit f4e2f5e1a527ce58fc9f85145b03704779a3123e ]

This patch rearranges gfs2_add_revoke so that the extra glock
reference is added earlier on in the function to avoid races in which
the glock is freed before the new reference is taken.

Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Bob Peterson 
Signed-off-by: Sasha Levin

gfs2: move privileged user check to gfs2_quota_lock_check

2020-06-03T06:23:02+00:00

[ Upstream commit 4ed0c30811cb4d30ef89850b787a53a84d5d2bcb ]

Before this patch, function gfs2_quota_lock checked if it was called
from a privileged user, and if so, it bypassed the quota check:
superuser can operate outside the quotas.
That's the wrong place for the check because the lock/unlock functions
are separate from the lock_check function, and you can do lock and
unlock without actually checking the quotas.

This patch moves the check to gfs2_quota_lock_check.

Signed-off-by: Bob Peterson 
Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Sasha Levin

Revert "gfs2: Don't demote a glock until its revokes are written"

2020-05-27T15:48:20+00:00

[ Upstream commit b14c94908b1b884276a6608dea3d0b1b510338b7 ]

This reverts commit df5db5f9ee112e76b5202fbc331f990a0fc316d6.

This patch fixes a regression: patch df5db5f9ee112 allowed function
run_queue() to bypass its call to do_xmote() if revokes were queued for
the glock. That's wrong because its call to do_xmote() is what is
responsible for calling the go_sync() glops functions to sync both
the ail list and any revokes queued for it. By bypassing the call,
gfs2 could get into a stand-off where the glock could not be demoted
until its revokes are written back, but the revokes would not be
written back because do_xmote() was never called.

It "sort of" works, however, because there are other mechanisms like
the log flush daemon (logd) that can sync the ail items and revokes,
if it deems it necessary. The problem is: without file system pressure,
it might never deem it necessary.

Signed-off-by: Bob Peterson 
Signed-off-by: Sasha Levin

gfs2: More gfs2_find_jhead fixes

2020-05-20T06:22:16+00:00

[ Upstream commit aa83da7f47b26c9587bade6c4bc4736ffa308f0a ]

It turns out that when extending an existing bio, gfs2_find_jhead fails to
check if the block number is consecutive, which leads to incorrect reads for
fragmented journals.

In addition, limit the maximum bio size to an arbitrary value of 2 megabytes:
since commit 07173c3ec276 ("block: enable multipage bvecs"), if we just keep
adding pages until bio_add_page fails, bios will grow much larger than useful,
which pins more memory than necessary with barely any additional performance
gains.

Fixes: f4686c26ecc3 ("gfs2: read journal in large chunks")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Bob Peterson 
Signed-off-by: Sasha Levin

gfs2: Another gfs2_walk_metadata fix

2020-05-20T06:22:10+00:00

[ Upstream commit 566a2ab3c9005f62e784bd39022d58d34ef4365c ]

Make sure we don't walk past the end of the metadata in gfs2_walk_metadata: the
inode holds fewer pointers than indirect blocks.

Slightly clean up gfs2_iomap_get.

Fixes: a27a0c9b6a20 ("gfs2: gfs2_walk_metadata fix")
Cc: stable@vger.kernel.org # v5.3+
Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Bob Peterson 
Signed-off-by: Sasha Levin

gfs2: clear ail1 list when gfs2 withdraws

2020-04-23T08:37:58+00:00

[ Upstream commit 30fe70a85a909a23dcbc2c628ca6655b2c85e7a1 ]

This patch fixes a bug in which function gfs2_log_flush can get into
an infinite loop when a gfs2 file system is withdrawn. The problem
is the infinite loop "for (;;)" in gfs2_log_flush which would never
finish because the io error and subsequent withdraw prevented the
items from being taken off the ail list.

This patch tries to clean up the mess by allowing withdraw situations
to move not-in-flight buffer_heads to the ail2 list, where they will
be dealt with later.

Signed-off-by: Bob Peterson 
Reviewed-by: Andreas Gruenbacher 
Signed-off-by: Sasha Levin

gfs2: Don't demote a glock until its revokes are written

2020-04-17T14:13:21+00:00

[ Upstream commit df5db5f9ee112e76b5202fbc331f990a0fc316d6 ]

Before this patch, run_queue would demote glocks based on whether
there are any more holders. But if the glock has pending revokes that
haven't been written to the media, giving up the glock might end in
file system corruption if the revokes never get written due to
io errors, node crashes and fences, etc. In that case, another node
will replay the metadata blocks associated with the glock, but
because the revoke was never written, it could replay that block
even though the glock had since been granted to another node who
might have made changes.

This patch changes the logic in run_queue so that it never demotes
a glock until its count of pending revokes reaches zero.

Signed-off-by: Bob Peterson 
Reviewed-by: Andreas Gruenbacher 
Signed-off-by: Sasha Levin

gfs2: Do log_flush in gfs2_ail_empty_gl even if ail list is empty

2020-04-17T14:13:21+00:00

[ Upstream commit 9ff78289356af640941bbb0dd3f46af2063f0046 ]

Before this patch, if gfs2_ail_empty_gl saw there was nothing on
the ail list, it would return and not flush the log. The problem
is that there could still be a revoke for the rgrp sitting on the
sd_log_le_revoke list that's been recently taken off the ail list.
But that revoke still needs to be written, and the rgrp_go_inval
still needs to call log_flush_wait to ensure the revokes are all
properly written to the journal before we relinquish control of
the glock to another node. If we give the glock to another node
before we have this knowledge, the node might crash and its journal
replayed, in which case the missing revoke would allow the journal
replay to replay the rgrp over top of the rgrp we already gave to
another node, thus overwriting its changes and corrupting the
file system.

This patch makes gfs2_ail_empty_gl still call gfs2_log_flush rather
than returning.

Signed-off-by: Bob Peterson 
Reviewed-by: Andreas Gruenbacher 
Signed-off-by: Sasha Levin

gfs2_atomic_open(): fix O_EXCL|O_CREAT handling on cold dcache

2020-03-12T22:21:24+00:00

with the way fs/namei.c:do_last() had been done, ->atomic_open()
instances needed to recognize the case when existing file got
found with O_EXCL|O_CREAT, either by falling back to finish_no_open()
or failing themselves.  gfs2 one didn't.

Fixes: 6d4ade986f9c (GFS2: Add atomic_open support)
Cc: stable@kernel.org # v3.11
Signed-off-by: Al Viro