[XFS] split out two helpers from xfs_syncsub

Split out two helpers from xfs_syncsub for the dummy log commit and the
superblock writeout.

SGI-PV: 988140

SGI-Modid: xfs-linux-melb:xfs-kern:32303a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

1 files changed, 93 insertions, 69 deletions

diff --git a/fs/xfs/linux-2.6/xfs_sync.c b/fs/xfs/linux-2.6/xfs_sync.c
index 53d85ecb1d50..59da3327a6b5 100644
--- a/fs/xfs/linux-2.6/xfs_sync.c
+++ b/fs/xfs/linux-2.6/xfs_sync.c
@@ -315,6 +315,93 @@ xfs_sync_inodes(
         return XFS_ERROR(last_error);
 }
 
+STATIC int
+xfs_commit_dummy_trans(
+        struct xfs_mount        *mp,
+        uint                    log_flags)
+{
+        struct xfs_inode        *ip = mp->m_rootip;
+        struct xfs_trans        *tp;
+        int                     error;
+
+        /*
+         * Put a dummy transaction in the log to tell recovery
+         * that all others are OK.
+         */
+        tp = xfs_trans_alloc(mp, XFS_TRANS_DUMMY1);
+        error = xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES(mp), 0, 0, 0);
+        if (error) {
+                xfs_trans_cancel(tp, 0);
+                return error;
+        }
+
+        xfs_ilock(ip, XFS_ILOCK_EXCL);
+
+        xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
+        xfs_trans_ihold(tp, ip);
+        xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+        /* XXX(hch): ignoring the error here.. */
+        error = xfs_trans_commit(tp, 0);
+
+        xfs_iunlock(ip, XFS_ILOCK_EXCL);
+
+        xfs_log_force(mp, 0, log_flags);
+        return 0;
+}
+
+STATIC int
+xfs_sync_fsdata(
+        struct xfs_mount        *mp,
+        int                     flags)
+{
+        struct xfs_buf          *bp;
+        struct xfs_buf_log_item *bip;
+        int                     error = 0;
+
+        /*
+         * If this is xfssyncd() then only sync the superblock if we can
+         * lock it without sleeping and it is not pinned.
+         */
+        if (flags & SYNC_BDFLUSH) {
+                ASSERT(!(flags & SYNC_WAIT));
+
+                bp = xfs_getsb(mp, XFS_BUF_TRYLOCK);
+                if (!bp)
+                        goto out;
+
+                bip = XFS_BUF_FSPRIVATE(bp, struct xfs_buf_log_item *);
+                if (!bip || !xfs_buf_item_dirty(bip) || XFS_BUF_ISPINNED(bp))
+                        goto out_brelse;
+        } else {
+                bp = xfs_getsb(mp, 0);
+
+                /*
+                 * If the buffer is pinned then push on the log so we won't
+                 * get stuck waiting in the write for someone, maybe
+                 * ourselves, to flush the log.
+                 *
+                 * Even though we just pushed the log above, we did not have
+                 * the superblock buffer locked at that point so it can
+                 * become pinned in between there and here.
+                 */
+                if (XFS_BUF_ISPINNED(bp))
+                        xfs_log_force(mp, 0, XFS_LOG_FORCE);
+        }
+
+
+        if (flags & SYNC_WAIT)
+                XFS_BUF_UNASYNC(bp);
+        else
+                XFS_BUF_ASYNC(bp);
+
+        return xfs_bwrite(mp, bp);
+
+ out_brelse:
+        xfs_buf_relse(bp);
+ out:
+        return error;
+}
+
 /*
  * xfs sync routine for internal use
  *
@@ -331,8 +418,6 @@ xfs_syncsub(
         int             error = 0;
         int             last_error = 0;
         uint            log_flags = XFS_LOG_FORCE;
-        xfs_buf_t       *bp;
-        xfs_buf_log_item_t      *bip;
 
         /*
          * Sync out the log.  This ensures that the log is periodically
@@ -355,83 +440,22 @@ xfs_syncsub(
          * log activity, so if this isn't vfs_sync() then flush
          * the log again.
          */
-        if (flags & SYNC_DELWRI) {
-                xfs_log_force(mp, (xfs_lsn_t)0, log_flags);
-        }
+        if (flags & SYNC_DELWRI)
+                xfs_log_force(mp, 0, log_flags);
 
         if (flags & SYNC_FSDATA) {
-                /*
-                 * If this is vfs_sync() then only sync the superblock
-                 * if we can lock it without sleeping and it is not pinned.
-                 */
-                if (flags & SYNC_BDFLUSH) {
-                        bp = xfs_getsb(mp, XFS_BUF_TRYLOCK);
-                        if (bp != NULL) {
-                                bip = XFS_BUF_FSPRIVATE(bp,xfs_buf_log_item_t*);
-                                if ((bip != NULL) &&
-                                    xfs_buf_item_dirty(bip)) {
-                                        if (!(XFS_BUF_ISPINNED(bp))) {
-                                                XFS_BUF_ASYNC(bp);
-                                                error = xfs_bwrite(mp, bp);
-                                        } else {
-                                                xfs_buf_relse(bp);
-                                        }
-                                } else {
-                                        xfs_buf_relse(bp);
-                                }
-                        }
-                } else {
-                        bp = xfs_getsb(mp, 0);
-                        /*
-                         * If the buffer is pinned then push on the log so
-                         * we won't get stuck waiting in the write for
-                         * someone, maybe ourselves, to flush the log.
-                         * Even though we just pushed the log above, we
-                         * did not have the superblock buffer locked at
-                         * that point so it can become pinned in between
-                         * there and here.
-                         */
-                        if (XFS_BUF_ISPINNED(bp))
-                                xfs_log_force(mp, (xfs_lsn_t)0, XFS_LOG_FORCE);
-                        if (flags & SYNC_WAIT)
-                                XFS_BUF_UNASYNC(bp);
-                        else
-                                XFS_BUF_ASYNC(bp);
-                        error = xfs_bwrite(mp, bp);
-                }
-                if (error) {
+                error = xfs_sync_fsdata(mp, flags);
+                if (error)
                         last_error = error;
-                }
         }
 
         /*
          * Now check to see if the log needs a "dummy" transaction.
          */
         if (!(flags & SYNC_REMOUNT) && xfs_log_need_covered(mp)) {
-                xfs_trans_t *tp;
-                xfs_inode_t *ip;
-
-                /*
-                 * Put a dummy transaction in the log to tell
-                 * recovery that all others are OK.
-                 */
-                tp = xfs_trans_alloc(mp, XFS_TRANS_DUMMY1);
-                if ((error = xfs_trans_reserve(tp, 0,
-                                XFS_ICHANGE_LOG_RES(mp),
-                                0, 0, 0)))  {
-                        xfs_trans_cancel(tp, 0);
+                error = xfs_commit_dummy_trans(mp, log_flags);
+                if (error)
                         return error;
-                }
-
-                ip = mp->m_rootip;
-                xfs_ilock(ip, XFS_ILOCK_EXCL);
-
-                xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
-                xfs_trans_ihold(tp, ip);
-                xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
-                error = xfs_trans_commit(tp, 0);
-                xfs_iunlock(ip, XFS_ILOCK_EXCL);
-                xfs_log_force(mp, (xfs_lsn_t)0, log_flags);
         }
 
         /*