[Linux-stable-mirror] [PATCH] ceph: decease session->s_trim_caps only after caps get trimmed
d_prune_aliases() does not prune dentry that has non-zero reference count. If we want trim_caps() to trim 'N' caps, the first 'N' inodes in session->s_caps are all directories with child dentry, trim_caps() can fail to trim anything.
Cc: stable@vger.kernel.org Signed-off-by: "Yan, Zheng" zyan@redhat.com --- fs/ceph/mds_client.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index 80339e278ad8..da181acd4a61 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -1490,16 +1490,20 @@ static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg) if ((used | wanted) & ~oissued & mine) goto out; /* we need these caps */
- session->s_trim_caps--; if (oissued) { /* we aren't the only cap.. just remove us */ __ceph_remove_cap(cap, true); + session->s_trim_caps--; } else { + int refs; /* try dropping referring dentries */ spin_unlock(&ci->i_ceph_lock); d_prune_aliases(inode); + refs = atomic_read(&inode->i_count); + if (refs == 1) + session->s_trim_caps--; dout("trim_caps_cb %p cap %p pruned, count now %d\n", - inode, cap, atomic_read(&inode->i_count)); + inode, cap, refs); return 0; }
Please ignore this mail.
On 30 Nov 2017, at 15:53, Yan, Zheng zyan@redhat.com wrote:
d_prune_aliases() does not prune dentry that has non-zero reference count. If we want trim_caps() to trim 'N' caps, the first 'N' inodes in session->s_caps are all directories with child dentry, trim_caps() can fail to trim anything.
Cc: stable@vger.kernel.org Signed-off-by: "Yan, Zheng" zyan@redhat.com
fs/ceph/mds_client.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index 80339e278ad8..da181acd4a61 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -1490,16 +1490,20 @@ static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg) if ((used | wanted) & ~oissued & mine) goto out; /* we need these caps */
- session->s_trim_caps--; if (oissued) { /* we aren't the only cap.. just remove us */ __ceph_remove_cap(cap, true);
session->s_trim_caps--;int refs;refs = atomic_read(&inode->i_count);if (refs == 1)session->s_trim_caps--;
inode, cap, atomic_read(&inode->i_count));
inode, cap, refs);-- 2.13.6
On Thu, 2017-11-30 at 15:53 +0800, Yan, Zheng wrote:
d_prune_aliases() does not prune dentry that has non-zero reference count. If we want trim_caps() to trim 'N' caps, the first 'N' inodes in session->s_caps are all directories with child dentry, trim_caps() can fail to trim anything.
Cc: stable@vger.kernel.org Signed-off-by: "Yan, Zheng" zyan@redhat.com
fs/ceph/mds_client.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index 80339e278ad8..da181acd4a61 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -1490,16 +1490,20 @@ static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg) if ((used | wanted) & ~oissued & mine) goto out; /* we need these caps */
- session->s_trim_caps--; if (oissued) { /* we aren't the only cap.. just remove us */ __ceph_remove_cap(cap, true);
session->s_trim_caps--;int refs;refs = atomic_read(&inode->i_count);if (refs == 1)session->s_trim_caps--;
inode, cap, atomic_read(&inode->i_count));
inode, cap, refs);
Reviewed-by: Jeff Layton jlayton@redhat.com
linux-stable-mirror@lists.linaro.org
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Jeff Layton -
Yan, Zheng