diff options
| author | David Howells <dhowells@redhat.com> | 2017-01-18 15:29:25 +0100 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2017-01-31 19:23:09 +0100 |
| commit | 6bdded59c8933940ac7e5b416448276ac89d1144 (patch) | |
| tree | 0620c0018aef6e596711114622e40d2f408e4bd3 /fs/fscache/object.c | |
| parent | FS-Cache: Initialise stores_lock in netfs cookie (diff) | |
| download | linux-6bdded59c8933940ac7e5b416448276ac89d1144.tar.xz linux-6bdded59c8933940ac7e5b416448276ac89d1144.zip | |
fscache: Clear outstanding writes when disabling a cookie
fscache_disable_cookie() needs to clear the outstanding writes on the
cookie it's disabling because they cannot be completed after.
Without this, fscache_nfs_open_file() gets stuck because it disables the
cookie when the file is opened for writing but can't uncache the pages till
afterwards - otherwise there's a race between the open routine and anyone
who already has it open R/O and is still reading from it.
Looking in /proc/pid/stack of the offending process shows:
[<ffffffffa0142883>] __fscache_wait_on_page_write+0x82/0x9b [fscache]
[<ffffffffa014336e>] __fscache_uncache_all_inode_pages+0x91/0xe1 [fscache]
[<ffffffffa01740fa>] nfs_fscache_open_file+0x59/0x9e [nfs]
[<ffffffffa01ccf41>] nfs4_file_open+0x17f/0x1b8 [nfsv4]
[<ffffffff8117350e>] do_dentry_open+0x16d/0x2b7
[<ffffffff811743ac>] vfs_open+0x5c/0x65
[<ffffffff81184185>] path_openat+0x785/0x8fb
[<ffffffff81184343>] do_filp_open+0x48/0x9e
[<ffffffff81174710>] do_sys_open+0x13b/0x1cb
[<ffffffff811747b9>] SyS_open+0x19/0x1b
[<ffffffff81001c44>] do_syscall_64+0x80/0x17a
[<ffffffff8165c2da>] return_from_SYSCALL_64+0x0/0x7a
[<ffffffffffffffff>] 0xffffffffffffffff
Reported-by: Jianhong Yin <jiyin@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to '')
| -rw-r--r-- | fs/fscache/object.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/fscache/object.c b/fs/fscache/object.c index 9e792e30f4db..be02a086ed9b 100644 --- a/fs/fscache/object.c +++ b/fs/fscache/object.c @@ -645,6 +645,12 @@ static const struct fscache_state *fscache_kill_object(struct fscache_object *ob fscache_mark_object_dead(object); object->oob_event_mask = 0; + if (test_bit(FSCACHE_OBJECT_RETIRED, &object->flags)) { + /* Reject any new read/write ops and abort any that are pending. */ + clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags); + fscache_cancel_all_ops(object); + } + if (list_empty(&object->dependents) && object->n_ops == 0 && object->n_children == 0) |