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| author | Yan, Zheng <zheng.z.yan@intel.com> | 2013-07-02 12:40:19 +0800 |
|---|---|---|
| committer | Sage Weil <sage@inktank.com> | 2013-07-03 15:32:56 -0700 |
| commit | b415bf4f9fe25f39934f5c464125e4a2dffb6d08 (patch) | |
| tree | f38df9c1746a1419e7942afb4534625175a5d353 /fs/ceph/caps.c | |
| parent | 5446429630257f4723829409337a26c076907d5d (diff) | |
| download | blackbird-op-linux-b415bf4f9fe25f39934f5c464125e4a2dffb6d08.tar.gz blackbird-op-linux-b415bf4f9fe25f39934f5c464125e4a2dffb6d08.zip | |
ceph: fix pending vmtruncate race
The locking order for pending vmtruncate is wrong, it can lead to
following race:
write wmtruncate work
------------------------ ----------------------
lock i_mutex
check i_truncate_pending check i_truncate_pending
truncate_inode_pages() lock i_mutex (blocked)
copy data to page cache
unlock i_mutex
truncate_inode_pages()
The fix is take i_mutex before calling __ceph_do_pending_vmtruncate()
Fixes: http://tracker.ceph.com/issues/5453
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Diffstat (limited to 'fs/ceph/caps.c')
| -rw-r--r-- | fs/ceph/caps.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 8ec27b130cc9..16266f3e9a33 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -2057,7 +2057,11 @@ static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want, /* finish pending truncate */ while (ci->i_truncate_pending) { spin_unlock(&ci->i_ceph_lock); - __ceph_do_pending_vmtruncate(inode, !(need & CEPH_CAP_FILE_WR)); + if (!(need & CEPH_CAP_FILE_WR)) + mutex_lock(&inode->i_mutex); + __ceph_do_pending_vmtruncate(inode); + if (!(need & CEPH_CAP_FILE_WR)) + mutex_unlock(&inode->i_mutex); spin_lock(&ci->i_ceph_lock); } |
