diff options
| author | Yan, Zheng <zyan@redhat.com> | 2014-12-23 15:30:54 +0800 |
|---|---|---|
| committer | Ilya Dryomov <idryomov@gmail.com> | 2015-02-19 13:31:38 +0300 |
| commit | 982d6011bc30a26e8a3d546e0e7fc7db2c255d85 (patch) | |
| tree | 3d1ee68f03edac2d64b7683baf15821cf14bdef7 /fs/ceph/mds_client.c | |
| parent | 1487a688d8ea596e6710b0d256300ab10ce99284 (diff) | |
| download | linux-982d6011bc30a26e8a3d546e0e7fc7db2c255d85.tar.bz2 | |
ceph: improve reference tracking for snaprealm
When snaprealm is created, its initial reference count is zero.
But in some rare cases, the newly created snaprealm is not referenced
by anyone. This causes snaprealm with zero reference count not freed.
The fix is set reference count of newly snaprealm to 1. The reference
is return the function who requests to create the snaprealm. When the
function finishes its job, it releases the reference.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Diffstat (limited to 'fs/ceph/mds_client.c')
| -rw-r--r-- | fs/ceph/mds_client.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index c6c33b411a2f..85c67ae03e46 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -2286,6 +2286,7 @@ static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg) struct ceph_mds_request *req; struct ceph_mds_reply_head *head = msg->front.iov_base; struct ceph_mds_reply_info_parsed *rinfo; /* parsed reply info */ + struct ceph_snap_realm *realm; u64 tid; int err, result; int mds = session->s_mds; @@ -2401,11 +2402,13 @@ static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg) } /* snap trace */ + realm = NULL; if (rinfo->snapblob_len) { down_write(&mdsc->snap_rwsem); ceph_update_snap_trace(mdsc, rinfo->snapblob, - rinfo->snapblob + rinfo->snapblob_len, - le32_to_cpu(head->op) == CEPH_MDS_OP_RMSNAP); + rinfo->snapblob + rinfo->snapblob_len, + le32_to_cpu(head->op) == CEPH_MDS_OP_RMSNAP, + &realm); downgrade_write(&mdsc->snap_rwsem); } else { down_read(&mdsc->snap_rwsem); @@ -2423,6 +2426,8 @@ static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg) mutex_unlock(&req->r_fill_mutex); up_read(&mdsc->snap_rwsem); + if (realm) + ceph_put_snap_realm(mdsc, realm); out_err: mutex_lock(&mdsc->mutex); if (!req->r_aborted) { |