@@ -1133,7 +1133,8 @@ void ceph_invalidate_dentry_lease(struct dentry *dentry)
* Check if dentry lease is valid. If not, delete the lease. Try to
* renew if the least is more than half up.
*/
-static int dentry_lease_is_valid(struct dentry *dentry)
+static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags,
+ struct inode *dir)
{
struct ceph_dentry_info *di;
struct ceph_mds_session *s;
@@ -1141,12 +1142,11 @@ static int dentry_lease_is_valid(struct dentry *dentry)
u32 gen;
unsigned long ttl;
struct ceph_mds_session *session = NULL;
- struct inode *dir = NULL;
u32 seq = 0;
spin_lock(&dentry->d_lock);
di = ceph_dentry(dentry);
- if (di->lease_session) {
+ if (di && di->lease_session) {
s = di->lease_session;
spin_lock(&s->s_gen_ttl_lock);
gen = s->s_cap_gen;
@@ -1159,12 +1159,19 @@ static int dentry_lease_is_valid(struct dentry *dentry)
valid = 1;
if (di->lease_renew_after &&
time_after(jiffies, di->lease_renew_after)) {
- /* we should renew */
- dir = d_inode(dentry->d_parent);
- session = ceph_get_mds_session(s);
- seq = di->lease_seq;
- di->lease_renew_after = 0;
- di->lease_renew_from = jiffies;
+ /*
+ * We should renew. If we're in RCU walk mode
+ * though, we can't do that so just return
+ * -ECHILD.
+ */
+ if (flags & LOOKUP_RCU) {
+ valid = -ECHILD;
+ } else {
+ session = ceph_get_mds_session(s);
+ seq = di->lease_seq;
+ di->lease_renew_after = 0;
+ di->lease_renew_from = jiffies;
+ }
}
}
}
@@ -1224,12 +1231,16 @@ static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
} else if (d_really_is_positive(dentry) &&
ceph_snap(d_inode(dentry)) == CEPH_SNAPDIR) {
valid = 1;
- } else if (dentry_lease_is_valid(dentry) ||
- dir_lease_is_valid(dir, dentry)) {
- if (d_really_is_positive(dentry))
- valid = ceph_is_any_caps(d_inode(dentry));
- else
- valid = 1;
+ } else {
+ valid = dentry_lease_is_valid(dentry, flags, dir);
+ if (valid == -ECHILD)
+ return valid;
+ if (valid || dir_lease_is_valid(dir, dentry)) {
+ if (d_really_is_positive(dentry))
+ valid = ceph_is_any_caps(d_inode(dentry));
+ else
+ valid = 1;
+ }
}
if (!valid) {
Under rcuwalk, we need to take extra care when dereferencing d_parent. We want to do that once and pass a pointer to dentry_lease_is_valid. Also, we must ensure that that function can handle the case where we're racing with d_release. Check whether "di" is NULL under the d_lock, and just return 0 if so. Finally, we still need to kick off a renewal job if the lease is getting close to expiration. If that's the case, then just drop out of rcuwalk mode since that could block. Signed-off-by: Jeff Layton <jlayton@redhat.com> --- fs/ceph/dir.c | 41 ++++++++++++++++++++++++++--------------- 1 file changed, 26 insertions(+), 15 deletions(-)