xfs: force the log if we encounter pinned buffers in .iop_pushbuf

We need to check for pinned buffers even in .iop_pushbuf given that inode
items flush into the same buffers that may be pinned directly due operations
on the unlinked inode list operating directly on buffers.  To do this add a
return value to .iop_pushbuf that tells the AIL push about this and use
the existing log force mechanisms to unpin it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Stefan Priebe <s.priebe@profihost.ag>
Tested-by: Stefan Priebe <s.priebe@profihost.ag>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>

5 files changed, 24 insertions, 10 deletions

diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c
index cac2ecfa6746..ef43fce519a1 100644
--- a/fs/xfs/xfs_buf_item.c
+++ b/fs/xfs/xfs_buf_item.c
@@ -629,7 +629,7 @@ xfs_buf_item_push(
  * the xfsbufd to get this buffer written. We have to unlock the buffer
  * to allow the xfsbufd to write it, too.
  */
-STATIC void
+STATIC bool
 xfs_buf_item_pushbuf(
         struct xfs_log_item     *lip)
 {
@@ -643,6 +643,7 @@ xfs_buf_item_pushbuf(
 
         xfs_buf_delwri_promote(bp);
         xfs_buf_relse(bp);
+        return true;
 }
 
 STATIC void
diff --git a/fs/xfs/xfs_dquot_item.c b/fs/xfs/xfs_dquot_item.c
index 9e0e2fa3f2c8..bb3f71d236d2 100644
--- a/fs/xfs/xfs_dquot_item.c
+++ b/fs/xfs/xfs_dquot_item.c
@@ -183,13 +183,14 @@ xfs_qm_dqunpin_wait(
  * search the buffer cache can be a time consuming thing, and AIL lock is a
  * spinlock.
  */
-STATIC void
+STATIC bool
 xfs_qm_dquot_logitem_pushbuf(
         struct xfs_log_item     *lip)
 {
         struct xfs_dq_logitem   *qlip = DQUOT_ITEM(lip);
         struct xfs_dquot        *dqp = qlip->qli_dquot;
         struct xfs_buf          *bp;
+        bool                    ret = true;
 
         ASSERT(XFS_DQ_IS_LOCKED(dqp));
 
@@ -201,17 +202,20 @@ xfs_qm_dquot_logitem_pushbuf(
         if (completion_done(&dqp->q_flush) ||
             !(lip->li_flags & XFS_LI_IN_AIL)) {
                 xfs_dqunlock(dqp);
-                return;
+                return true;
         }
 
         bp = xfs_incore(dqp->q_mount->m_ddev_targp, qlip->qli_format.qlf_blkno,
                         dqp->q_mount->m_quotainfo->qi_dqchunklen, XBF_TRYLOCK);
         xfs_dqunlock(dqp);
         if (!bp)
-                return;
+                return true;
         if (XFS_BUF_ISDELAYWRITE(bp))
                 xfs_buf_delwri_promote(bp);
+        if (xfs_buf_ispinned(bp))
+                ret = false;
         xfs_buf_relse(bp);
+        return ret;
 }
 
 /*
diff --git a/fs/xfs/xfs_inode_item.c b/fs/xfs/xfs_inode_item.c
index 588406dc6a35..836ad80d4f2b 100644
--- a/fs/xfs/xfs_inode_item.c
+++ b/fs/xfs/xfs_inode_item.c
@@ -708,13 +708,14 @@ xfs_inode_item_committed(
  * marked delayed write. If that's the case, we'll promote it and that will
  * allow the caller to write the buffer by triggering the xfsbufd to run.
  */
-STATIC void
+STATIC bool
 xfs_inode_item_pushbuf(
         struct xfs_log_item     *lip)
 {
         struct xfs_inode_log_item *iip = INODE_ITEM(lip);
         struct xfs_inode        *ip = iip->ili_inode;
         struct xfs_buf          *bp;
+        bool                    ret = true;
 
         ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED));
 
@@ -725,7 +726,7 @@ xfs_inode_item_pushbuf(
         if (completion_done(&ip->i_flush) ||
             !(lip->li_flags & XFS_LI_IN_AIL)) {
                 xfs_iunlock(ip, XFS_ILOCK_SHARED);
-                return;
+                return true;
         }
 
         bp = xfs_incore(ip->i_mount->m_ddev_targp, iip->ili_format.ilf_blkno,
@@ -733,10 +734,13 @@ xfs_inode_item_pushbuf(
 
         xfs_iunlock(ip, XFS_ILOCK_SHARED);
         if (!bp)
-                return;
+                return true;
         if (XFS_BUF_ISDELAYWRITE(bp))
                 xfs_buf_delwri_promote(bp);
+        if (xfs_buf_ispinned(bp))
+                ret = false;
         xfs_buf_relse(bp);
+        return ret;
 }
 
 /*
diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index 06a9759b6352..53597f4db9b5 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -350,7 +350,7 @@ typedef struct xfs_item_ops {
         void (*iop_unlock)(xfs_log_item_t *);
         xfs_lsn_t (*iop_committed)(xfs_log_item_t *, xfs_lsn_t);
         void (*iop_push)(xfs_log_item_t *);
-        void (*iop_pushbuf)(xfs_log_item_t *);
+        bool (*iop_pushbuf)(xfs_log_item_t *);
         void (*iop_committing)(xfs_log_item_t *, xfs_lsn_t);
 } xfs_item_ops_t;
 
diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c
index 9bd1ee55ef6a..e4cd9180d33a 100644
--- a/fs/xfs/xfs_trans_ail.c
+++ b/fs/xfs/xfs_trans_ail.c
@@ -427,8 +427,13 @@ xfs_ail_worker(
 
                 case XFS_ITEM_PUSHBUF:
                         XFS_STATS_INC(xs_push_ail_pushbuf);
-                        IOP_PUSHBUF(lip);
-                        ailp->xa_last_pushed_lsn = lsn;
+
+                        if (!IOP_PUSHBUF(lip)) {
+                                stuck++;
+                                flush_log = 1;
+                        } else {
+                                ailp->xa_last_pushed_lsn = lsn;
+                        }
                         push_xfsbufd = 1;
                         break;