Commit Graph

412 Commits

Author SHA1 Message Date
Xiubo Li
b2f9fa1f3b ceph: correctly handle releasing an embedded cap flush
The ceph_cap_flush structures are usually dynamically allocated, but
the ceph_cap_snap has an embedded one.

When force umounting, the client will try to remove all the session
caps. During this, it will free them, but that should not be done
with the ones embedded in a capsnap.

Fix this by adding a new boolean that indicates that the cap flush is
embedded in a capsnap, and skip freeing it if that's set.

At the same time, switch to using list_del_init() when detaching the
i_list and g_list heads.  It's possible for a forced umount to remove
these objects but then handle_cap_flushsnap_ack() races in and does the
list_del_init() again, corrupting memory.

Cc: stable@vger.kernel.org
URL: https://tracker.ceph.com/issues/52283
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-08-25 16:34:11 +02:00
Luis Henriques
bf2ba43221 ceph: reduce contention in ceph_check_delayed_caps()
Function ceph_check_delayed_caps() is called from the mdsc->delayed_work
workqueue and it can be kept looping for quite some time if caps keep
being added back to the mdsc->cap_delay_list.  This may result in the
watchdog tainting the kernel with the softlockup flag.

This patch breaks this loop if the caps have been recently (i.e. during
the loop execution).  Any new caps added to the list will be handled in
the next run.

Also, allow schedule_delayed() callers to explicitly set the delay value
instead of defaulting to 5s, so we can ensure that it runs soon
afterward if it looks like there is more work.

Cc: stable@vger.kernel.org
URL: https://tracker.ceph.com/issues/46284
Signed-off-by: Luis Henriques <lhenriques@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-08-04 19:20:05 +02:00
Jeff Layton
23c2c76ead ceph: eliminate ceph_async_iput()
Now that we don't need to hold session->s_mutex or the snap_rwsem when
calling ceph_check_caps, we can eliminate ceph_async_iput and just use
normal iput calls.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-06-29 00:15:52 +02:00
Jeff Layton
7732fe168e ceph: don't take s_mutex in ceph_flush_snaps
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Luis Henriques <lhenriques@suse.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-06-29 00:15:52 +02:00
Jeff Layton
0449a35222 ceph: don't take s_mutex in try_flush_caps
The s_mutex doesn't protect anything in this codepath.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Luis Henriques <lhenriques@suse.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-06-29 00:15:52 +02:00
Jeff Layton
6a92b08fda ceph: don't take s_mutex or snap_rwsem in ceph_check_caps
These locks appear to be completely unnecessary. Almost all of this
function is done under the inode->i_ceph_lock, aside from the actual
sending of the message. Don't take either lock in this function.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Luis Henriques <lhenriques@suse.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-06-29 00:15:52 +02:00
Jeff Layton
52d60f8e18 ceph: eliminate session->s_gen_ttl_lock
Turn s_cap_gen field into an atomic_t, and just rely on the fact that we
hold the s_mutex when changing the s_cap_ttl field.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Luis Henriques <lhenriques@suse.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-06-29 00:15:52 +02:00
Linus Torvalds
7ac86b3dca Notable items here are a series to take advantage of David Howells'
netfs helper library from Jeff, three new filesystem client metrics
 from Xiubo, ceph.dir.rsnaps vxattr from Yanhu and two auth-related
 fixes from myself, marked for stable.  Interspersed is a smattering
 of assorted fixes and cleanups across the filesystem.
 -----BEGIN PGP SIGNATURE-----
 
 iQFHBAABCAAxFiEEydHwtzie9C7TfviiSn/eOAIR84sFAmCT8IITHGlkcnlvbW92
 QGdtYWlsLmNvbQAKCRBKf944AhHzizgqCACYbyY4Yr/2C8fZsn+P9rd97zRTbcC6
 eufTZwnlECLnc89BxJQRk9a2UpDJfC8RMM3/9tmiulc8G4M+ggVbdFQTCzsZox3c
 vLAunGeVyfKIY+16Bv2RNuoO3KeeZm5aB3jXJ5QcUPcXmd4XnHKI1FU2ebC56UJb
 pxxfHpE6fb59r6Ek1e5uUFyta4KDMrvwXozghuAPEgT1GpKeA9zMIGI0CkQbBHlW
 PWHpcahTiT6GWa/d9ud0CnfssiBxVydWyKTz9xppYC6LNdsZUf9tBmYYGRklcjoA
 yAwPSuqxNmg+7uWubEawc0+a/3fXORgp2SF7Rbp1XYE+HpfnMF1J+nIn
 =IO5c
 -----END PGP SIGNATURE-----

Merge tag 'ceph-for-5.13-rc1' of git://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:
 "Notable items here are

   - a series to take advantage of David Howells' netfs helper library
     from Jeff

   - three new filesystem client metrics from Xiubo

   - ceph.dir.rsnaps vxattr from Yanhu

   - two auth-related fixes from myself, marked for stable.

  Interspersed is a smattering of assorted fixes and cleanups across the
  filesystem"

* tag 'ceph-for-5.13-rc1' of git://github.com/ceph/ceph-client: (24 commits)
  libceph: allow addrvecs with a single NONE/blank address
  libceph: don't set global_id until we get an auth ticket
  libceph: bump CephXAuthenticate encoding version
  ceph: don't allow access to MDS-private inodes
  ceph: fix up some bare fetches of i_size
  ceph: convert some PAGE_SIZE invocations to thp_size()
  ceph: support getting ceph.dir.rsnaps vxattr
  ceph: drop pinned_page parameter from ceph_get_caps
  ceph: fix inode leak on getattr error in __fh_to_dentry
  ceph: only check pool permissions for regular files
  ceph: send opened files/pinned caps/opened inodes metrics to MDS daemon
  ceph: avoid counting the same request twice or more
  ceph: rename the metric helpers
  ceph: fix kerneldoc copypasta over ceph_start_io_direct
  ceph: use attach/detach_page_private for tracking snap context
  ceph: don't use d_add in ceph_handle_snapdir
  ceph: don't clobber i_snap_caps on non-I_NEW inode
  ceph: fix fall-through warnings for Clang
  ceph: convert ceph_readpages to ceph_readahead
  ceph: convert ceph_write_begin to netfs_write_begin
  ...
2021-05-06 10:27:02 -07:00
Jeff Layton
2d6795fbb8 ceph: fix up some bare fetches of i_size
We need to use i_size_read(), which properly handles the torn read
case on 32-bit arches.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-04-27 23:52:23 +02:00
Jeff Layton
e72968e15b ceph: drop pinned_page parameter from ceph_get_caps
All of the existing callers that don't set this to NULL just drop the
page reference at some arbitrary point later in processing. There's no
point in keeping a page reference that we don't use, so just drop the
reference immediately after checking the Uptodate flag.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-04-27 23:52:23 +02:00
Jeff Layton
10a7052c78 ceph: fix fscache invalidation
Ensure that we invalidate the fscache whenever we invalidate the
pagecache.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-04-27 23:52:22 +02:00
Jeff Layton
e7df4524cd ceph: rip out old fscache readpage handling
With the new netfs read helper functions, we won't need a lot of this
infrastructure as it handles the pagecache pages itself. Rip out the
read handling for now, and much of the old infrastructure that deals in
individual pages.

The cookie handling is mostly unchanged, however.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-04-27 23:52:21 +02:00
Jeff Layton
ed94f87c2b ceph: don't allow type or device number to change on non-I_NEW inodes
Al pointed out that a malicious or broken MDS could change the type or
device number of a given inode number. It may also be possible for the
MDS to reuse an old inode number.

Ensure that we never allow fill_inode to change the type part of the
i_mode or the i_rdev unless I_NEW is set. Throw warnings if the MDS ever
changes these on us mid-stream, and return an error.

Don't set i_rdev directly, and rely on init_special_inode to do it.
Also, fix up error handling in the callers of ceph_get_inode.

In handle_cap_grant, check for and warn if the inode type changes, and
only overwrite the mode if it didn't.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-08 10:19:37 -05:00
Xiubo Li
558b4510f6 ceph: defer flushing the capsnap if the Fb is used
If the Fb cap is used it means the current inode is flushing the
dirty data to OSD, just defer flushing the capsnap.

URL: https://tracker.ceph.com/issues/48640
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-02-16 12:09:52 +01:00
Jeff Layton
a8810cdc00 ceph: allow queueing cap/snap handling after putting cap references
Testing with the fscache overhaul has triggered some lockdep warnings
about circular lock dependencies involving page_mkwrite and the
mmap_lock. It'd be better to do the "real work" without the mmap lock
being held.

Change the skip_checking_caps parameter in __ceph_put_cap_refs to an
enum, and use that to determine whether to queue check_caps, do it
synchronously or not at all. Change ceph_page_mkwrite to do a
ceph_put_cap_refs_async().

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-02-16 12:09:51 +01:00
Jeff Layton
64f36da562 ceph: fix flush_snap logic after putting caps
A primary reason for skipping ceph_check_caps after putting the
references was to avoid the locking in ceph_check_caps during a
reconnect. __ceph_put_cap_refs can still call ceph_flush_snaps in that
case though, and that takes many of the same inconvenient locks.

Fix the logic in __ceph_put_cap_refs to skip flushing snaps when the
skip_checking_caps flag is set.

Fixes: e64f44a884 ("ceph: skip checking caps when session reconnecting and releasing reqs")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-02-16 12:09:51 +01:00
Luis Henriques
e5cafce3ad ceph: fix race in concurrent __ceph_remove_cap invocations
A NULL pointer dereference may occur in __ceph_remove_cap with some of the
callbacks used in ceph_iterate_session_caps, namely trim_caps_cb and
remove_session_caps_cb. Those callers hold the session->s_mutex, so they
are prevented from concurrent execution, but ceph_evict_inode does not.

Since the callers of this function hold the i_ceph_lock, the fix is simply
a matter of returning immediately if caps->ci is NULL.

Cc: stable@vger.kernel.org
URL: https://tracker.ceph.com/issues/43272
Suggested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Luis Henriques <lhenriques@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Jeff Layton
06a1ad438b ceph: fix up some warnings on W=1 builds
Convert some decodes into unused variables into skips, and fix up some
non-kerneldoc comment headers to not start with "/**".

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Jeff Layton
50c9132ddf ceph: add new RECOVER mount_state when recovering session
When recovering a session (a'la recover_session=clean), we want to do
all of the operations that we do on a forced umount, but changing the
mount state to SHUTDOWN is can cause queued MDS requests to fail when
the session comes back. Most of those can idle until the session is
recovered in this situation.

Reserve SHUTDOWN state for forced umount, and make a new RECOVER state
for the forced reconnect situation. Change several tests for equality with
SHUTDOWN to test for that or RECOVER.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:46 +01:00
Jeff Layton
dc167e38a0 ceph: don't WARN when removing caps due to blocklisting
We expect to remove dirty caps when the client is blocklisted. Don't
throw a warning in that case.

[ idryomov: break unnecessarily long line ]

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:46 +01:00
Jeff Layton
62575e270f ceph: check session state after bumping session->s_seq
Some messages sent by the MDS entail a session sequence number
increment, and the MDS will drop certain types of requests on the floor
when the sequence numbers don't match.

In particular, a REQUEST_CLOSE message can cross with one of the
sequence morphing messages from the MDS which can cause the client to
stall, waiting for a response that will never come.

Originally, this meant an up to 5s delay before the recurring workqueue
job kicked in and resent the request, but a recent change made it so
that the client would never resend, causing a 60s stall unmounting and
sometimes a blockisting event.

Add a new helper for incrementing the session sequence and then testing
to see whether a REQUEST_CLOSE needs to be resent, and move the handling
of CEPH_MDS_SESSION_CLOSING into that function. Change all of the
bare sequence counter increments to use the new helper.

Reorganize check_session_state with a switch statement.  It should no
longer be called when the session is CLOSING, so throw a warning if it
ever is (but still handle that case sanely).

[ idryomov: whitespace, pr_err() call fixup ]

URL: https://tracker.ceph.com/issues/47563
Fixes: fa99677342 ("ceph: fix potential mdsc use-after-free crash")
Reported-by: Patrick Donnelly <pdonnell@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-11-04 20:55:49 +01:00
Jeff Layton
c74d79af90 ceph: comment cleanups and clarifications
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:27 +02:00
Jeff Layton
16d68903f5 ceph: break up send_cap_msg
Push the allocation of the msg and the send into the caller. Rename
the function to encode_cap_msg and make it void return.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:27 +02:00
Jeff Layton
5231198089 ceph: drop separate mdsc argument from __send_cap
We can get it from the session if we need it.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:27 +02:00
Xiubo Li
1dd8d47081 ceph: metrics for opened files, pinned caps and opened inodes
In client for each inode, it may have many opened files and may
have been pinned in more than one MDS servers. And some inodes
are idle, which have no any opened files.

This patch will show these metrics in the debugfs, likes:

item                               total
-----------------------------------------
opened files  / total inodes       14 / 5
pinned i_caps / total inodes       7  / 5
opened inodes / total inodes       3  / 5

Will send these metrics to ceph, which will be used by the `fs top`,
later.

[ jlayton: drop unrelated hunk, count hashed inodes instead of
           allocated ones ]

URL: https://tracker.ceph.com/issues/47005
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:26 +02:00
Xiubo Li
2678da88f4 ceph: add ceph_sb_to_mdsc helper support to parse the mdsc
This will help simplify the code.

[ jlayton: fix minor merge conflict in quota.c ]

Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:26 +02:00
Jeff Layton
ebce3eb2f7 ceph: fix inode number handling on arches with 32-bit ino_t
Tuan and Ulrich mentioned that they were hitting a problem on s390x,
which has a 32-bit ino_t value, even though it's a 64-bit arch (for
historical reasons).

I think the current handling of inode numbers in the ceph driver is
wrong. It tries to use 32-bit inode numbers on 32-bit arches, but that's
actually not a problem. 32-bit arches can deal with 64-bit inode numbers
just fine when userland code is compiled with LFS support (the common
case these days).

What we really want to do is just use 64-bit numbers everywhere, unless
someone has mounted with the ino32 mount option. In that case, we want
to ensure that we hash the inode number down to something that will fit
in 32 bits before presenting the value to userland.

Add new helper functions that do this, and only do the conversion before
presenting these values to userland in getattr and readdir.

The inode table hashvalue is changed to just cast the inode number to
unsigned long, as low-order bits are the most likely to vary anyway.

While it's not strictly required, we do want to put something in
inode->i_ino. Instead of basing it on BITS_PER_LONG, however, base it on
the size of the ino_t type.

NOTE: This is a user-visible change on 32-bit arches:

1/ inode numbers will be seen to have changed between kernel versions.
   32-bit arches will see large inode numbers now instead of the hashed
   ones they saw before.

2/ any really old software not built with LFS support may start failing
   stat() calls with -EOVERFLOW on inode numbers >2^32. Nothing much we
   can do about these, but hopefully the intersection of people running
   such code on ceph will be very small.

The workaround for both problems is to mount with "-o ino32".

[ idryomov: changelog tweak ]

URL: https://tracker.ceph.com/issues/46828
Reported-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Reported-and-Tested-by: Tuan Hoang1 <Tuan.Hoang1@ibm.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-08-24 17:25:26 +02:00
Jeff Layton
585d72f33e ceph: clean up and optimize ceph_check_delayed_caps()
Make this loop look a bit more sane. Also optimize away the spinlock
release/reacquire if we can't get an inode reference.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-08-03 11:05:21 +02:00
Xiubo Li
4f1d756def ceph: add global total_caps to count the mdsc's total caps number
This will help to reduce using the global mdsc->mutex lock in many
places.

Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-08-03 11:05:15 +02:00
Xiubo Li
e64f44a884 ceph: skip checking caps when session reconnecting and releasing reqs
It make no sense to check the caps when reconnecting to mds. And
for the async dirop caps, they will be put by its _cb() function,
so when releasing the requests, it will make no sense too.

URL: https://tracker.ceph.com/issues/45635
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-06-01 13:22:53 +02:00
Jeff Layton
829ad4db95 ceph: ceph_kick_flushing_caps needs the s_mutex
The mdsc->cap_dirty_lock is not held while walking the list in
ceph_kick_flushing_caps, which is not safe.

ceph_early_kick_flushing_caps does something similar, but the
s_mutex is held while it's called and I think that guards against
changes to the list.

Ensure we hold the s_mutex when calling ceph_kick_flushing_caps,
and add some clarifying comments.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-06-01 13:22:53 +02:00
Jeff Layton
d67c72e6cc ceph: request expedited service on session's last cap flush
When flushing a lot of caps to the MDS's at once (e.g. for syncfs),
we can end up waiting a substantial amount of time for MDS replies, due
to the fact that it may delay some of them so that it can batch them up
together in a single journal transaction. This can lead to stalls when
calling sync or syncfs.

What we'd really like to do is request expedited service on the _last_
cap we're flushing back to the server. If the CHECK_CAPS_FLUSH flag is
set on the request and the current inode was the last one on the
session->s_cap_dirty list, then mark the request with
CEPH_CLIENT_CAPS_SYNC.

Note that this heuristic is not perfect. New inodes can race onto the
list after we've started flushing, but it does seem to fix some common
use cases.

URL: https://tracker.ceph.com/issues/44744
Reported-by: Jan Fajerski <jfajerski@suse.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-06-01 13:22:52 +02:00
Jeff Layton
1cf03a68e7 ceph: convert mdsc->cap_dirty to a per-session list
This is a per-sb list now, but that makes it difficult to tell when
the cap is the last dirty one associated with the session. Switch
this to be a per-session list, but continue using the
mdsc->cap_dirty_lock to protect the lists.

This list is only ever walked in ceph_flush_dirty_caps, so change that
to walk the sessions array and then flush the caps for inodes on each
session's list.

If the auth cap ever changes while the inode has dirty caps, then
move the inode to the appropriate session for the new auth_cap. Also,
ensure that we never remove an auth cap while the inode is still on the
s_cap_dirty list.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-06-01 13:22:52 +02:00
Yan, Zheng
6f05b30ea0 ceph: reset i_requested_max_size if file write is not wanted
write can stuck at waiting for larger max_size in following sequence of
events:

- client opens a file and writes to position 'A' (larger than unit of
  max size increment)
- client closes the file handle and updates wanted caps (not wanting
  file write caps)
- client opens and truncates the file, writes to position 'A' again.

At the 1st event, client set inode's requested_max_size to 'A'. At the
2nd event, mds removes client's writable range, but client does not reset
requested_max_size. At the 3rd event, client does not request max size
because requested_max_size is already larger than 'A'.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-06-01 13:22:52 +02:00
Jeff Layton
dc3da0461c ceph: fix potential race in ceph_check_caps
Nothing ensures that session will still be valid by the time we
dereference the pointer. Take and put a reference.

In principle, we should always be able to get a reference here, but
throw a warning if that's ever not the case.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-06-01 13:22:52 +02:00
Jeff Layton
7833323363 ceph: don't take i_ceph_lock in handle_cap_import
Just take it before calling it. This means we have to do a couple of
minor in-memory operations under the spinlock now, but those shouldn't
be an issue.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-06-01 13:22:52 +02:00
Jeff Layton
7391fba267 ceph: don't release i_ceph_lock in handle_cap_trunc
There's no reason to do this here. Just have the caller handle it.
Also, add a lockdep assertion.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-06-01 13:22:52 +02:00
Jeff Layton
d7dbfb4f2b ceph: add comments for handle_cap_flush_ack logic
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-06-01 13:22:52 +02:00
Jeff Layton
681ac63488 ceph: split up __finish_cap_flush
This function takes a mdsc argument or ci argument, but if both are
passed in, it ignores the ci arg. Fortunately, nothing does that, but
there's no good reason to have the same function handle both cases.

Also, get rid of some branches and just use |= to set the wake_* vals.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-06-01 13:22:52 +02:00
Jeff Layton
0a454bdd50 ceph: reorganize __send_cap for less spinlock abuse
Get rid of the __releases annotation by breaking it up into two
functions: __prep_cap which is done under the spinlock and __send_cap
that is done outside it. Add new fields to cap_msg_args for the wake
boolean and old_xattr_buf pointer.

Nothing checks the return value from __send_cap, so make it void
return.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-06-01 13:22:51 +02:00
Xiubo Li
1af16d547f ceph: add caps perf metric for each superblock
Count hits and misses in the caps cache. If the client has all of
the necessary caps when a task needs references, then it's counted
as a hit. Any other situation is a miss.

URL: https://tracker.ceph.com/issues/43215
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-06-01 13:22:51 +02:00
Jeff Layton
fb33c114d3 ceph: flush release queue when handling caps for unknown inode
It's possible for the VFS to completely forget about an inode, but for
it to still be sitting on the cap release queue. If the MDS sends the
client a cap message for such an inode, it just ignores it today, which
can lead to a stall of up to 5s until the cap release queue is flushed.

If we get a cap message for an inode that can't be located, then go
ahead and flush the cap release queue.

Cc: stable@vger.kernel.org
URL: https://tracker.ceph.com/issues/45532
Fixes: 1e9c2eb681 ("ceph: delete stale dentry when last reference is dropped")
Reported-and-Tested-by: Andrej Filipčič <andrej.filipcic@ijs.si>
Suggested-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-05-27 13:03:57 +02:00
Wu Bo
4d8e28ff31 ceph: fix double unlock in handle_cap_export()
If the ceph_mdsc_open_export_target_session() return fails, it will
do a "goto retry", but the session mutex has already been unlocked.
Re-lock the mutex in that case to ensure that we don't unlock it
twice.

Signed-off-by: Wu Bo <wubo40@huawei.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-05-04 19:14:23 +02:00
Wu Bo
7d8976afad ceph: fix special error code in ceph_try_get_caps()
There are 3 speical error codes: -EAGAIN/-EFBIG/-ESTALE.
After calling try_get_cap_refs, ceph_try_get_caps test for the
-EAGAIN twice. Ensure that it tests for -ESTALE instead.

Signed-off-by: Wu Bo <wubo40@huawei.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-05-04 19:14:23 +02:00
Yan, Zheng
9bccb76574 ceph: wait for async creating inode before requesting new max size
ceph_check_caps() can't request new max size for async creating inode.
This may make ceph_get_caps() loop busily until getting reply of the
async create. Also, wait for async creating reply before calling
ceph_renew_caps().

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:43 +02:00
Yan, Zheng
0aa971b6fd ceph: don't skip updating wanted caps when cap is stale
1. try_get_cap_refs() fails to get caps and finds that mds_wanted
   does not include what it wants. It returns -ESTALE.
2. ceph_get_caps() calls ceph_renew_caps(). ceph_renew_caps() finds
   that inode has cap, so it calls ceph_check_caps().
3. ceph_check_caps() finds that issued caps (without checking if it's
   stale) already includes caps wanted by open file, so it skips
   updating wanted caps.

Above events can cause an infinite loop inside ceph_get_caps().

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:43 +02:00
Yan, Zheng
42d70f8e31 ceph: request new max size only when there is auth cap
When there is no auth cap, check_max_size() can't do anything and may
cause an infinite loop inside ceph_get_caps().

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:43 +02:00
Yan, Zheng
546d402085 ceph: cleanup return error of try_get_cap_refs()
Returns 0 if caps were not able to be acquired (yet), 1 if cap
acquisition succeeded, or a negative error code. There are 3 special
error codes:

-EAGAIN: need to sleep but non-blocking is specified
-EFBIG:  ask caller to call check_max_size() and try again.
-ESTALE: ask caller to call ceph_renew_caps() and try again.

[ jlayton: add WARN_ON_ONCE check for -EAGAIN ]

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:42 +02:00
Yan, Zheng
bf73c62e7f ceph: check all mds' caps after page writeback
If an inode has caps from multiple mds's, the following can happen:

- non-auth mds revokes Fsc. Fcb is used, so page writeback is queued.
- when writeback finishes, ceph_check_caps() is called with auth only
  flag. ceph_check_caps() invalidates pagecache, but skips checking any
  non-auth caps.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:42 +02:00
Yan, Zheng
11ba6b9cee ceph: update i_requested_max_size only when sending cap msg to auth mds
Non-auth mds can't do anything to 'update max' cap message.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:42 +02:00
Yan, Zheng
135e671e54 ceph: simplify calling of ceph_get_fmode()
Originally, calling ceph_get_fmode() for open files is by thread that
handles request reply. There is a small window between updating caps and
and waking the request initiator. We need to prevent ceph_check_caps()
from releasing wanted caps in the window.

Previous patches made fill_inode() call __ceph_touch_fmode() for open file
requests. This prevented ceph_check_caps() from releasing wanted caps for
'caps_wanted_delay_min' seconds, enough for request initiator to get
woken up and call ceph_get_fmode().

This allows us to now call ceph_get_fmode() in ceph_open() instead.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:42 +02:00
Yan, Zheng
a0d93e327f ceph: remove delay check logic from ceph_check_caps()
__ceph_caps_file_wanted() already checks 'caps_wanted_delay_min' and
'caps_wanted_delay_max'. There is no need to duplicate the logic in
ceph_check_caps() and __send_cap()

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:42 +02:00
Yan, Zheng
719a2514e9 ceph: consider inode's last read/write when calculating wanted caps
Add i_last_rd and i_last_wr to ceph_inode_info. These fields are
used to track the last time the client acquired read/write caps for
the inode.

If there is no read/write on an inode for 'caps_wanted_delay_max'
seconds, __ceph_caps_file_wanted() does not request caps for read/write
even there are open files.

Call __ceph_touch_fmode() for dir operations. __ceph_caps_file_wanted()
calculates dir's wanted caps according to last dir read/modification. If
there is recent dir read, dir inode wants CEPH_CAP_ANY_SHARED caps. If
there is recent dir modification, also wants CEPH_CAP_FILE_EXCL.

Readdir is a special case. Dir inode wants CEPH_CAP_FILE_EXCL after
readdir, as with that, modifications do not need to release
CEPH_CAP_FILE_SHARED or invalidate all dentry leases issued by readdir.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:42 +02:00
Yan, Zheng
c0e385b106 ceph: always renew caps if mds_wanted is insufficient
Original code only renews caps for inodes with CEPH_I_CAP_DROPPED flag,
which indicates that mds has closed the session and caps were dropped.
Remove this flag in preparation for not requesting caps for idle open
files.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:42 +02:00
Jeff Layton
785892fe88 ceph: cache layout in parent dir on first sync create
If a create is done, then typically we'll end up writing to the file
soon afterward. We don't want to wait for the reply before doing that
when doing an async create, so that means we need the layout for the
new file before we've gotten the response from the MDS.

All files created in a directory will initially inherit the same layout,
so copy off the requisite info from the first synchronous create in the
directory, and save it in a new i_cached_layout field. Zero out the
layout when we lose Dc caps in the dir.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:42 +02:00
Yan, Zheng
173e70e8ac ceph: don't take refs to want mask unless we have all bits
If we don't have all of the cap bits for the want mask in
try_get_cap_refs, then just take refs on the need bits.

Signed-off-by: "Yan, Zheng" <ukernel@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:41 +02:00
Jeff Layton
a25949b990 ceph: cap tracking for async directory operations
Track and correctly handle directory caps for asynchronous operations.
Add aliases for Frc caps that we now designate at Dcu caps (when dealing
with directories).

Unlike file caps, we don't reclaim these when the session goes away, and
instead preemptively release them. In-flight async dirops are instead
handled during reconnect phase. The client needs to re-do a synchronous
operation in order to re-get directory caps.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:41 +02:00
Jeff Layton
40dcf75e82 ceph: make __take_cap_refs non-static
Rename it to ceph_take_cap_refs and make it available to other files.
Also replace a comment with a lockdep assertion.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:41 +02:00
Jeff Layton
891f3f5a6a ceph: add infrastructure for waiting for async create to complete
When we issue an async create, we must ensure that any later on-the-wire
requests involving it wait for the create reply.

Expand i_ceph_flags to be an unsigned long, and add a new bit that
MDS requests can wait on. If the bit is set in the inode when sending
caps, then don't send it and just return that it has been delayed.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:41 +02:00
Jeff Layton
c7e4f85ce9 ceph: more caps.c lockdep assertions
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:41 +02:00
Jeff Layton
e8a4d26771 ceph: clean up kick_flushing_inode_caps()
The last thing that this function does is release i_ceph_lock, so
have the caller do that instead. Add a lockdep assertion to
ensure that the function is always called with i_ceph_lock held.
Change the prototype to take a ceph_inode_info pointer and drop
the separate mdsc argument as we can get that from the session.

While at it, make it non-static.  We'll need this to kick any
flushing caps once the create reply comes in.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:41 +02:00
Yan, Zheng
525d15e8e5 ceph: check inode type for CEPH_CAP_FILE_{CACHE,RD,REXTEND,LAZYIO}
These bits will have new meaning for directory inodes.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:40 +02:00
Jeff Layton
f85122afeb ceph: add refcounting for Fx caps
In future patches we'll be taking and relying on Fx caps. Add proper
refcounting for them.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-03-30 12:42:40 +02:00
Xiubo Li
9f8b72b3a9 ceph: only touch the caps which have the subset mask requested
For the caps having no any subset mask requested we shouldn't touch
them.

Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-01-27 16:53:39 +01:00
Xiubo Li
bd84fbcb31 ceph: switch to global cap helper
__ceph_is_any_caps is a duplicate helper.

Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-12-09 20:55:10 +01:00
Jeff Layton
3a3430affc ceph: show tasks waiting on caps in debugfs caps file
Add some visibility of tasks that are waiting for caps to the "caps"
debugfs file. Display the tgid of the waiting task, inode number, and
the caps the task needs and wants.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-12-09 20:55:10 +01:00
Luis Henriques
ea60ed6fcf ceph: fix use-after-free in __ceph_remove_cap()
KASAN reports a use-after-free when running xfstest generic/531, with the
following trace:

[  293.903362]  kasan_report+0xe/0x20
[  293.903365]  rb_erase+0x1f/0x790
[  293.903370]  __ceph_remove_cap+0x201/0x370
[  293.903375]  __ceph_remove_caps+0x4b/0x70
[  293.903380]  ceph_evict_inode+0x4e/0x360
[  293.903386]  evict+0x169/0x290
[  293.903390]  __dentry_kill+0x16f/0x250
[  293.903394]  dput+0x1c6/0x440
[  293.903398]  __fput+0x184/0x330
[  293.903404]  task_work_run+0xb9/0xe0
[  293.903410]  exit_to_usermode_loop+0xd3/0xe0
[  293.903413]  do_syscall_64+0x1a0/0x1c0
[  293.903417]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

This happens because __ceph_remove_cap() may queue a cap release
(__ceph_queue_cap_release) which can be scheduled before that cap is
removed from the inode list with

	rb_erase(&cap->ci_node, &ci->i_caps);

And, when this finally happens, the use-after-free will occur.

This can be fixed by removing the cap from the inode list before being
removed from the session list, and thus eliminating the risk of an UAF.

Cc: stable@vger.kernel.org
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-10-29 22:29:51 +01:00
Jeff Layton
98cd281a76 ceph: remove incorrect comment above __send_cap
It doesn't do anything to invalidate the cache when dropping RD caps.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-09-16 12:06:24 +02:00
Jeff Layton
daca8bda95 ceph: remove CEPH_I_NOFLUSH
Nothing sets this flag.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-09-16 12:06:24 +02:00
Jeff Layton
27b0a39209 ceph: remove unneeded test in try_flush_caps
cap->session is always non-NULL, so we can just do a single test for
equality w/o testing explicitly for a NULL pointer.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-09-16 12:06:24 +02:00
Jeff Layton
9f3345d8ec ceph: have __mark_caps_flushing return flush_tid
Currently, this function returns ci->i_dirty_caps, but the callers have
to check that that isn't 0 before calling this function. Have the
callers grab that value directly out of the inode, and have
__mark_caps_flushing return the flush_tid instead.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-09-16 12:06:24 +02:00
Jeff Layton
354c63a003 ceph: fix comments over ceph_add_cap
We actually need the ci->i_ceph_lock here. The necessity of the s_mutex
is less clear. Also add a lockdep assertion for the i_ceph_lock.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-09-16 12:06:24 +02:00
Jeff Layton
606d102327 ceph: fetch cap_gen under spinlock in ceph_add_cap
It's protected by the s_gen_ttl_lock, so we should fetch under it
and ensure that we're using the same generation in both places.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-09-16 12:06:24 +02:00
Jeff Layton
5de16b30d3 ceph: remove ceph_get_cap_mds and __ceph_get_cap_mds
Nothing calls these routines.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-09-16 12:06:24 +02:00
Yan, Zheng
81f148a910 ceph: invalidate all write mode filp after reconnect
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-09-16 12:06:24 +02:00
Yan, Zheng
ff5d913dfc ceph: return -EIO if read/write against filp that lost file locks
After mds evicts session, file locks get lost sliently. It's not safe to
let programs continue to do read/write.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-09-16 12:06:24 +02:00
Yan, Zheng
5e3ded1bb6 ceph: pass filp to ceph_get_caps()
Also change several other functions' arguments, no logical changes.
This is preparetion for later patch that checks filp error.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-09-16 12:06:24 +02:00
Yan, Zheng
f4b9786622 ceph: track and report error of async metadata operation
Use errseq_t to track and report errors of async metadata operations,
similar to how kernel handles errors during writeback.

If any dirty caps or any unsafe request gets dropped during session
eviction, record -EIO in corresponding inode's i_meta_err. The error
will be reported by subsequent fsync,

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-09-16 12:06:23 +02:00
Luis Henriques
12fe3dda7e ceph: fix buffer free while holding i_ceph_lock in __ceph_build_xattrs_blob()
Calling ceph_buffer_put() in __ceph_build_xattrs_blob() may result in
freeing the i_xattrs.blob buffer while holding the i_ceph_lock.  This can
be fixed by having this function returning the old blob buffer and have
the callers of this function freeing it when the lock is released.

The following backtrace was triggered by fstests generic/117.

  BUG: sleeping function called from invalid context at mm/vmalloc.c:2283
  in_atomic(): 1, irqs_disabled(): 0, pid: 649, name: fsstress
  4 locks held by fsstress/649:
   #0: 00000000a7478e7e (&type->s_umount_key#19){++++}, at: iterate_supers+0x77/0xf0
   #1: 00000000f8de1423 (&(&ci->i_ceph_lock)->rlock){+.+.}, at: ceph_check_caps+0x7b/0xc60
   #2: 00000000562f2b27 (&s->s_mutex){+.+.}, at: ceph_check_caps+0x3bd/0xc60
   #3: 00000000f83ce16a (&mdsc->snap_rwsem){++++}, at: ceph_check_caps+0x3ed/0xc60
  CPU: 1 PID: 649 Comm: fsstress Not tainted 5.2.0+ #439
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014
  Call Trace:
   dump_stack+0x67/0x90
   ___might_sleep.cold+0x9f/0xb1
   vfree+0x4b/0x60
   ceph_buffer_release+0x1b/0x60
   __ceph_build_xattrs_blob+0x12b/0x170
   __send_cap+0x302/0x540
   ? __lock_acquire+0x23c/0x1e40
   ? __mark_caps_flushing+0x15c/0x280
   ? _raw_spin_unlock+0x24/0x30
   ceph_check_caps+0x5f0/0xc60
   ceph_flush_dirty_caps+0x7c/0x150
   ? __ia32_sys_fdatasync+0x20/0x20
   ceph_sync_fs+0x5a/0x130
   iterate_supers+0x8f/0xf0
   ksys_sync+0x4f/0xb0
   __ia32_sys_sync+0xa/0x10
   do_syscall_64+0x50/0x1c0
   entry_SYSCALL_64_after_hwframe+0x49/0xbe
  RIP: 0033:0x7fc6409ab617

Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-08-22 10:47:41 +02:00
Yan, Zheng
49ada6e8dc ceph: more precise CEPH_CLIENT_CAPS_PENDING_CAPSNAP
Client uses this flag to tell mds if there is more cap snap need to
flush. It's mainly for the case that client needs to re-send cap/snap
flushes after mds failover, but CEPH_CAP_ANY_FILE_WR on corresponding
inodes are all released before mds failover.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-07-08 14:01:44 +02:00
Yan, Zheng
d6cee9dbd8 ceph: kick flushing and flush snaps before sending normal cap message
Otherwise client may send cap flush messages in wrong order.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-07-08 14:01:44 +02:00
Yan, Zheng
054f8d41af ceph: clear CEPH_I_KICK_FLUSH flag inside __kick_flushing_caps()
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-07-08 14:01:44 +02:00
Jeff Layton
176c77c9c9 ceph: handle change_attr in cap messages
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-07-08 14:01:43 +02:00
Jeff Layton
ec62b894df ceph: handle btime in cap messages
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-07-08 14:01:43 +02:00
Yan, Zheng
ac6713ccb5 ceph: add selinux support
When creating new file/directory, use security_dentry_init_security() to
prepare selinux context for the new inode, then send openc/mkdir request
to MDS, together with selinux xattr.

security_dentry_init_security() only supports single security module and
only selinux has dentry_init_security hook. So only selinux is supported
for now. We can add support for other security modules once kernel has a
generic version of dentry_init_security()

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-07-08 14:01:42 +02:00
Yan, Zheng
d6e4781972 ceph: hold i_ceph_lock when removing caps for freeing inode
ceph_d_revalidate(, LOOKUP_RCU) may call __ceph_caps_issued_mask()
on a freeing inode.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-07-08 14:01:42 +02:00
Yan, Zheng
7b2f936fc8 ceph: fix error handling in ceph_get_caps()
The function return 0 even when interrupted or try_get_cap_refs()
return error.

Fixes: 1199d7da2d ("ceph: simplify arguments and return semantics of try_get_cap_refs")
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-06-05 20:34:39 +02:00
Yan, Zheng
3e1d0452ed ceph: avoid iput_final() while holding mutex or in dispatch thread
iput_final() may wait for reahahead pages. The wait can cause deadlock.
For example:

  Workqueue: ceph-msgr ceph_con_workfn [libceph]
    Call Trace:
     schedule+0x36/0x80
     io_schedule+0x16/0x40
     __lock_page+0x101/0x140
     truncate_inode_pages_range+0x556/0x9f0
     truncate_inode_pages_final+0x4d/0x60
     evict+0x182/0x1a0
     iput+0x1d2/0x220
     iterate_session_caps+0x82/0x230 [ceph]
     dispatch+0x678/0xa80 [ceph]
     ceph_con_workfn+0x95b/0x1560 [libceph]
     process_one_work+0x14d/0x410
     worker_thread+0x4b/0x460
     kthread+0x105/0x140
     ret_from_fork+0x22/0x40

  Workqueue: ceph-msgr ceph_con_workfn [libceph]
    Call Trace:
     __schedule+0x3d6/0x8b0
     schedule+0x36/0x80
     schedule_preempt_disabled+0xe/0x10
     mutex_lock+0x2f/0x40
     ceph_check_caps+0x505/0xa80 [ceph]
     ceph_put_wrbuffer_cap_refs+0x1e5/0x2c0 [ceph]
     writepages_finish+0x2d3/0x410 [ceph]
     __complete_request+0x26/0x60 [libceph]
     handle_reply+0x6c8/0xa10 [libceph]
     dispatch+0x29a/0xbb0 [libceph]
     ceph_con_workfn+0x95b/0x1560 [libceph]
     process_one_work+0x14d/0x410
     worker_thread+0x4b/0x460
     kthread+0x105/0x140
     ret_from_fork+0x22/0x40

In above example, truncate_inode_pages_range() waits for readahead pages
while holding s_mutex. ceph_check_caps() waits for s_mutex and blocks
OSD dispatch thread. Later OSD replies (for readahead) can't be handled.

ceph_check_caps() also may lock snap_rwsem for read. So similar deadlock
can happen if iput_final() is called while holding snap_rwsem.

In general, it's not good to call iput_final() inside MDS/OSD dispatch
threads or while holding any mutex.

The fix is introducing ceph_async_iput(), which calls iput_final() in
workqueue.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-06-05 20:34:39 +02:00
Jeff Layton
5ddc61fc14 ceph: print inode number in __caps_issued_mask debugging messages
To make it easier to correlate with MDS logs.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-05-07 19:22:38 +02:00
Jeff Layton
1199d7da2d ceph: simplify arguments and return semantics of try_get_cap_refs
The return of this function is rather complex. It can return 0 or 1,
and in the case of a 1 return, the "err" pointer will be filled out.
This necessitates a lot of copying of values.

We can achieve the same effect by just returning 0, 1 or a negative
error code, and drop the "err" argument from this function.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-05-07 19:22:38 +02:00
Jeff Layton
a452bc0636 ceph: fix comment over ceph_drop_caps_for_unlink
It's not clear what AUTH_RDCACHE means in this context, and we're
clearly just dropping LINK caps here.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-05-07 19:22:38 +02:00
Jeff Layton
ffb61c55b2 ceph: remove superfluous inode_lock in ceph_fsync
Originally, filemap_write_and_wait took the i_mutex internally, but
commit 02c24a8218 pushed the mutex acquisition into the individual
fsync routines, leaving it up to the subsystem maintainers to remove
it if it wasn't needed.

For ceph, I see no reason to take the inode_lock here. All of the
operations inside that lock are protected by their own locking.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-05-07 19:22:37 +02:00
Yan, Zheng
fe33032daa ceph: add mount option to limit caps count
If number of caps exceed the limit, ceph_trim_dentires() also trim
dentries with valid leases. Trimming dentry releases references to
associated inode, which may evict inode and release caps.

By default, there is no limit for caps count.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-03-05 18:55:17 +01:00
Yan, Zheng
32f6511a69 ceph: touch existing cap when handling reply
Move cap to tail of session->s_caps list. So ceph_trim_caps() will
trim older caps first.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-03-05 18:55:17 +01:00
Yan, Zheng
e3ec8d6898 ceph: send cap releases more aggressively
When pending cap releases fill up one message, start a work to send
cap release message. (old way is sending cap releases every 5 seconds)

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-03-05 18:55:16 +01:00
Yan, Zheng
81c5a1487e ceph: split large reconnect into multiple messages
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-03-05 18:55:16 +01:00
Yan, Zheng
d95e674c01 ceph: clear inode pointer when snap realm gets dropped by its inode
snap realm and corresponding inode have pointers to each other.
The two pointer should get clear at the same time. Otherwise,
snap realm's pointer may reference freed inode.

Cc: stable@vger.kernel.org # 4.17+
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Luis Henriques <lhenriques@suse.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-01-21 14:52:41 +01:00
Yan, Zheng
d2f8bb27c8 ceph: update wanted caps after resuming stale session
mds contains an optimization, it does not re-issue stale caps if
client does not want any cap.

A special case of the optimization is that client wants some caps,
but skipped updating 'wanted'. For this case, client needs to update
'wanted' when stale session get renewed.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2018-12-26 16:08:36 +01:00
Yan, Zheng
fdac94fab7 ceph: skip updating 'wanted' caps if caps are already issued
When reading cached inode that already has Fscr caps, this can avoid
two cap messages (one updats 'wanted' caps, one clears 'wanted' caps).

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2018-12-26 16:08:36 +01:00
Yan, Zheng
8a2ac3a8e9 ceph: don't request excl caps when mount is readonly
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2018-12-26 16:08:36 +01:00