xfs: kill XBF_FS_MANAGED buffers

Filesystem level managed buffers are buffers that have their
lifecycle controlled by the filesystem layer, not the buffer cache.
We currently cache these buffers, which makes cleanup and cache
walking somewhat troublesome. Convert the fs managed buffers to
uncached buffers obtained by via xfs_buf_get_uncached(), and remove
the XBF_FS_MANAGED special cases from the buffer cache.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>

1 files changed, 4 insertions, 16 deletions

diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index d6928970097f..975d6589394a 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -826,8 +826,6 @@ xfs_buf_rele(
                         atomic_inc(&bp->b_hold);
                         spin_unlock(&hash->bh_lock);
                         (*(bp->b_relse)) (bp);
-                } else if (bp->b_flags & XBF_FS_MANAGED) {
-                        spin_unlock(&hash->bh_lock);
                 } else {
                         ASSERT(!(bp->b_flags & (XBF_DELWRI|_XBF_DELWRI_Q)));
                         list_del_init(&bp->b_hash_list);
@@ -1433,26 +1431,16 @@ void
 xfs_wait_buftarg(
         xfs_buftarg_t   *btp)
 {
-        xfs_buf_t       *bp, *n;
         xfs_bufhash_t   *hash;
         uint            i;
 
         for (i = 0; i < (1 << btp->bt_hashshift); i++) {
                 hash = &btp->bt_hash[i];
-again:
                 spin_lock(&hash->bh_lock);
-                list_for_each_entry_safe(bp, n, &hash->bh_list, b_hash_list) {
-                        ASSERT(btp == bp->b_target);
-                        if (!(bp->b_flags & XBF_FS_MANAGED)) {
-                                spin_unlock(&hash->bh_lock);
-                                /*
-                                 * Catch superblock reference count leaks
-                                 * immediately
-                                 */
-                                BUG_ON(bp->b_bn == 0);
-                                delay(100);
-                                goto again;
-                        }
+                while (!list_empty(&hash->bh_list)) {
+                        spin_unlock(&hash->bh_lock);
+                        delay(100);
+                        spin_lock(&hash->bh_lock);
                 }
                 spin_unlock(&hash->bh_lock);
         }