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| author | Yan, Zheng <zheng.z.yan@intel.com> | 2013-04-12 16:11:10 +0800 |
|---|---|---|
| committer | Sage Weil <sage@inktank.com> | 2013-05-01 21:18:53 -0700 |
| commit | 37505d5768b9389a5ef7bc1efa465d4484a5462e (patch) | |
| tree | 208daa8785fe4847061a1dafee58ff32b5b861e6 | |
| parent | 26be88087ae8a04a5b576aa2f490597b649fc132 (diff) | |
| download | linux-37505d5768b9389a5ef7bc1efa465d4484a5462e.tar.gz linux-37505d5768b9389a5ef7bc1efa465d4484a5462e.tar.bz2 linux-37505d5768b9389a5ef7bc1efa465d4484a5462e.zip | |
ceph: take i_mutex before getting Fw cap
There is deadlock as illustrated bellow. The fix is taking i_mutex
before getting Fw cap reference.
write truncate MDS
--------------------- -------------------- --------------
get Fw cap
lock i_mutex
lock i_mutex (blocked)
request setattr.size ->
<- revoke Fw cap
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
| -rw-r--r-- | fs/ceph/caps.c | 13 | ||||
| -rw-r--r-- | fs/ceph/file.c | 12 |
2 files changed, 13 insertions, 12 deletions
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index f9563108d189..da0f9b8a3bcb 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -2052,6 +2052,13 @@ static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want, goto out; } + /* finish pending truncate */ + while (ci->i_truncate_pending) { + spin_unlock(&ci->i_ceph_lock); + __ceph_do_pending_vmtruncate(inode, !(need & CEPH_CAP_FILE_WR)); + spin_lock(&ci->i_ceph_lock); + } + if (need & CEPH_CAP_FILE_WR) { if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) { dout("get_cap_refs %p endoff %llu > maxsize %llu\n", @@ -2073,12 +2080,6 @@ static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want, } have = __ceph_caps_issued(ci, &implemented); - /* - * disallow writes while a truncate is pending - */ - if (ci->i_truncate_pending) - have &= ~CEPH_CAP_FILE_WR; - if ((have & need) == need) { /* * Look at (implemented & ~have & not) so that we keep waiting diff --git a/fs/ceph/file.c b/fs/ceph/file.c index a65acf355384..dd44f3593992 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -651,7 +651,6 @@ static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov, dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n", inode, ceph_vinop(inode), pos, (unsigned)len, inode); again: - __ceph_do_pending_vmtruncate(inode, true); if (fi->fmode & CEPH_FILE_MODE_LAZY) want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO; else @@ -728,7 +727,7 @@ retry_snap: ret = -ENOSPC; goto out; } - __ceph_do_pending_vmtruncate(inode, true); + mutex_lock(&inode->i_mutex); dout("aio_write %p %llx.%llx %llu~%u getting caps. i_size %llu\n", inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len, inode->i_size); @@ -737,8 +736,10 @@ retry_snap: else want = CEPH_CAP_FILE_BUFFER; ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, endoff); - if (ret < 0) - goto out_put; + if (ret < 0) { + mutex_unlock(&inode->i_mutex); + goto out; + } dout("aio_write %p %llx.%llx %llu~%u got cap refs on %s\n", inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len, @@ -748,10 +749,10 @@ retry_snap: (iocb->ki_filp->f_flags & O_DIRECT) || (inode->i_sb->s_flags & MS_SYNCHRONOUS) || (fi->flags & CEPH_F_SYNC)) { + mutex_unlock(&inode->i_mutex); ret = ceph_sync_write(file, iov->iov_base, iov->iov_len, &iocb->ki_pos); } else { - mutex_lock(&inode->i_mutex); ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos); mutex_unlock(&inode->i_mutex); @@ -766,7 +767,6 @@ retry_snap: __mark_inode_dirty(inode, dirty); } -out_put: dout("aio_write %p %llx.%llx %llu~%u dropping cap refs on %s\n", inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len, ceph_cap_string(got)); |