[01/11] ceph: handle cap export race in try_flush_caps()
diff mbox

Message ID 1390282239-23111-1-git-send-email-zheng.z.yan@intel.com
State New, archived
Headers show

Commit Message

Yan, Zheng Jan. 21, 2014, 5:30 a.m. UTC
auth cap may change after releasing the i_ceph_lock

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
---
 fs/ceph/caps.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

Comments

Sage Weil Jan. 21, 2014, 5:33 a.m. UTC | #1
On Tue, 21 Jan 2014, Yan, Zheng wrote:
> auth cap may change after releasing the i_ceph_lock
> 
> Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>

Reviewed-by: Sage Weil <sage@inktank.com>

> ---
>  fs/ceph/caps.c | 16 ++++++++--------
>  1 file changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
> index 80dad0d..1012099 100644
> --- a/fs/ceph/caps.c
> +++ b/fs/ceph/caps.c
> @@ -1735,13 +1735,12 @@ ack:
>  /*
>   * Try to flush dirty caps back to the auth mds.
>   */
> -static int try_flush_caps(struct inode *inode, struct ceph_mds_session *session,
> -			  unsigned *flush_tid)
> +static int try_flush_caps(struct inode *inode, unsigned *flush_tid)
>  {
>  	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
>  	struct ceph_inode_info *ci = ceph_inode(inode);
> -	int unlock_session = session ? 0 : 1;
>  	int flushing = 0;
> +	struct ceph_mds_session *session = NULL;
>  
>  retry:
>  	spin_lock(&ci->i_ceph_lock);
> @@ -1755,13 +1754,14 @@ retry:
>  		int want = __ceph_caps_wanted(ci);
>  		int delayed;
>  
> -		if (!session) {
> +		if (!session || session != cap->session) {
>  			spin_unlock(&ci->i_ceph_lock);
> +			if (session)
> +				mutex_unlock(&session->s_mutex);
>  			session = cap->session;
>  			mutex_lock(&session->s_mutex);
>  			goto retry;
>  		}
> -		BUG_ON(session != cap->session);
>  		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN)
>  			goto out;
>  
> @@ -1780,7 +1780,7 @@ retry:
>  out:
>  	spin_unlock(&ci->i_ceph_lock);
>  out_unlocked:
> -	if (session && unlock_session)
> +	if (session)
>  		mutex_unlock(&session->s_mutex);
>  	return flushing;
>  }
> @@ -1865,7 +1865,7 @@ int ceph_fsync(struct file *file, loff_t start, loff_t end, int datasync)
>  		return ret;
>  	mutex_lock(&inode->i_mutex);
>  
> -	dirty = try_flush_caps(inode, NULL, &flush_tid);
> +	dirty = try_flush_caps(inode, &flush_tid);
>  	dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));
>  
>  	/*
> @@ -1900,7 +1900,7 @@ int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
>  
>  	dout("write_inode %p wait=%d\n", inode, wait);
>  	if (wait) {
> -		dirty = try_flush_caps(inode, NULL, &flush_tid);
> +		dirty = try_flush_caps(inode, &flush_tid);
>  		if (dirty)
>  			err = wait_event_interruptible(ci->i_cap_wq,
>  				       caps_are_flushed(inode, flush_tid));
> -- 
> 1.8.4.2
> 
> 
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Patch
diff mbox

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 80dad0d..1012099 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -1735,13 +1735,12 @@  ack:
 /*
  * Try to flush dirty caps back to the auth mds.
  */
-static int try_flush_caps(struct inode *inode, struct ceph_mds_session *session,
-			  unsigned *flush_tid)
+static int try_flush_caps(struct inode *inode, unsigned *flush_tid)
 {
 	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
 	struct ceph_inode_info *ci = ceph_inode(inode);
-	int unlock_session = session ? 0 : 1;
 	int flushing = 0;
+	struct ceph_mds_session *session = NULL;
 
 retry:
 	spin_lock(&ci->i_ceph_lock);
@@ -1755,13 +1754,14 @@  retry:
 		int want = __ceph_caps_wanted(ci);
 		int delayed;
 
-		if (!session) {
+		if (!session || session != cap->session) {
 			spin_unlock(&ci->i_ceph_lock);
+			if (session)
+				mutex_unlock(&session->s_mutex);
 			session = cap->session;
 			mutex_lock(&session->s_mutex);
 			goto retry;
 		}
-		BUG_ON(session != cap->session);
 		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN)
 			goto out;
 
@@ -1780,7 +1780,7 @@  retry:
 out:
 	spin_unlock(&ci->i_ceph_lock);
 out_unlocked:
-	if (session && unlock_session)
+	if (session)
 		mutex_unlock(&session->s_mutex);
 	return flushing;
 }
@@ -1865,7 +1865,7 @@  int ceph_fsync(struct file *file, loff_t start, loff_t end, int datasync)
 		return ret;
 	mutex_lock(&inode->i_mutex);
 
-	dirty = try_flush_caps(inode, NULL, &flush_tid);
+	dirty = try_flush_caps(inode, &flush_tid);
 	dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));
 
 	/*
@@ -1900,7 +1900,7 @@  int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
 
 	dout("write_inode %p wait=%d\n", inode, wait);
 	if (wait) {
-		dirty = try_flush_caps(inode, NULL, &flush_tid);
+		dirty = try_flush_caps(inode, &flush_tid);
 		if (dirty)
 			err = wait_event_interruptible(ci->i_cap_wq,
 				       caps_are_flushed(inode, flush_tid));