linux/fs/afs
David Howells 2aeb8c86d4 afs: Fix afs_getattr() to refetch file status if callback break occurred
If a callback break occurs (change notification), afs_getattr() needs to
issue an FS.FetchStatus RPC operation to update the status of the file
being examined by the stat-family of system calls.

Fix afs_getattr() to do this if AFS_VNODE_CB_PROMISED has been cleared
on a vnode by a callback break.  Skip this if AT_STATX_DONT_SYNC is set.

This can be tested by appending to a file on one AFS client and then
using "stat -L" to examine its length on a machine running kafs.  This
can also be watched through tracing on the kafs machine.  The callback
break is seen:

     kworker/1:1-46      [001] .....   978.910812: afs_cb_call: c=0000005f YFSCB.CallBack
     kworker/1:1-46      [001] ...1.   978.910829: afs_cb_break: 100058:23b4c:242d2c2 b=2 s=1 break-cb
     kworker/1:1-46      [001] .....   978.911062: afs_call_done:    c=0000005f ret=0 ab=0 [0000000082994ead]

And then the stat command generated no traffic if unpatched, but with
this change a call to fetch the status can be observed:

            stat-4471    [000] .....   986.744122: afs_make_fs_call: c=000000ab 100058:023b4c:242d2c2 YFS.FetchStatus
            stat-4471    [000] .....   986.745578: afs_call_done:    c=000000ab ret=0 ab=0 [0000000087fc8c84]

Fixes: 08e0e7c82e ("[AF_RXRPC]: Make the in-kernel AFS filesystem use AF_RXRPC.")
Reported-by: Markus Suvanto <markus.suvanto@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Tested-by: Markus Suvanto <markus.suvanto@gmail.com>
Tested-by: kafs-testing+fedora34_64checkkafs-build-496@auristor.com
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216010
Link: https://lore.kernel.org/r/165308359800.162686.14122417881564420962.stgit@warthog.procyon.org.uk/ # v1
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-05-22 09:25:47 -10:00
..
addr_list.c afs: Use kfree_rcu() instead of casting kfree() to rcu_callback_t 2020-03-13 10:47:33 -07:00
afs_cm.h
afs_fs.h
afs_vl.h afs: Implement client support for the YFSVL.GetCellName RPC op 2020-06-04 15:37:57 +01:00
afs.h afs: Implement client support for the YFSVL.GetCellName RPC op 2020-06-04 15:37:57 +01:00
callback.c afs: Try to avoid taking RCU read lock when checking vnode validity 2021-09-13 09:10:39 +01:00
cell.c afs: Convert afs to use the new fscache API 2022-01-07 13:44:47 +00:00
cmservice.c afs: Fix tracepoint string placement with built-in AFS 2021-07-21 15:08:35 +01:00
dir_edit.c afs: Use folios in directory handling 2021-11-10 21:17:09 +00:00
dir_silly.c afs: Fix kerneldoc warning shown up by W=1 2021-10-04 22:04:44 +01:00
dir.c afs: Convert afs_dir_set_page_dirty() to afs_dir_dirty_folio() 2022-03-15 08:34:38 -04:00
dynroot.c netfs: Add a netfs inode context 2022-03-18 09:29:05 +00:00
file.c Netfs prep for write helpers 2022-03-31 15:49:36 -07:00
flock.c fs: remove mandatory file locking support 2021-08-23 06:15:36 -04:00
fs_operation.c afs: Fix speculative status fetches 2021-05-01 11:55:36 -07:00
fs_probe.c afs: Fix corruption in reads at fpos 2G-4G from an OpenAFS server 2021-09-13 09:14:21 +01:00
fsclient.c afs: Fix corruption in reads at fpos 2G-4G from an OpenAFS server 2021-09-13 09:14:21 +01:00
inode.c afs: Fix afs_getattr() to refetch file status if callback break occurred 2022-05-22 09:25:47 -10:00
internal.h Netfs prep for write helpers 2022-03-31 15:49:36 -07:00
Kconfig afs: Convert afs to use the new fscache API 2022-01-07 13:44:47 +00:00
main.c afs: Convert afs to use the new fscache API 2022-01-07 13:44:47 +00:00
Makefile afs: Convert afs to use the new fscache API 2022-01-07 13:44:47 +00:00
misc.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
mntpt.c afs: Stop listxattr() from listing "afs.*" attributes 2021-03-15 17:09:54 +00:00
proc.c proc: remove PDE_DATA() completely 2022-01-22 08:33:37 +02:00
protocol_afs.h afs: Fix corruption in reads at fpos 2G-4G from an OpenAFS server 2021-09-13 09:14:21 +01:00
protocol_uae.h
protocol_yfs.h afs: Fix corruption in reads at fpos 2G-4G from an OpenAFS server 2021-09-13 09:14:21 +01:00
rotate.c afs: Try to avoid taking RCU read lock when checking vnode validity 2021-09-13 09:10:39 +01:00
rxrpc.c afs: Use ITER_XARRAY for writing 2021-04-23 10:17:27 +01:00
security.c fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
server_list.c afs: Reorganise volume and server trees to be rooted on the cell 2020-06-04 15:37:57 +01:00
server.c afs: Fix mmap coherency vs 3rd-party changes 2021-09-13 09:10:39 +01:00
super.c Netfs prep for write helpers 2022-03-31 15:49:36 -07:00
vl_alias.c afs: Add tracing for cell refcount and active user count 2020-10-16 14:39:21 +01:00
vl_list.c afs: Don't use VL probe running state to make decisions outside probe code 2020-08-20 18:21:28 +01:00
vl_probe.c afs: Don't use VL probe running state to make decisions outside probe code 2020-08-20 18:21:28 +01:00
vl_rotate.c afs: Add tracing for cell refcount and active user count 2020-10-16 14:39:21 +01:00
vlclient.c afs: Fix fall-through warnings for Clang 2021-05-25 07:30:34 -10:00
volume.c afs: Convert afs to use the new fscache API 2022-01-07 13:44:47 +00:00
write.c fscache: Remove the cookie parameter from fscache_clear_page_bits() 2022-04-08 23:54:37 +01:00
xattr.c afs: Stop listxattr() from listing "afs.*" attributes 2021-03-15 17:09:54 +00:00
xdr_fs.h afs: Fix directory entry size calculation 2021-01-04 12:25:19 +00:00
yfsclient.c afs: Set mtime from the client for yfs create operations 2021-11-02 09:42:26 +00:00