xfs: remove the per-filesystem list of dquots

Instead of keeping a separate per-filesystem list of dquots we can walk
the radix tree for the two places where we need to iterate all quota
structures.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>

1 files changed, 3 insertions, 92 deletions

diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
index 49456e555cfa..2896ac953ed6 100644
--- a/fs/xfs/xfs_dquot.c
+++ b/fs/xfs/xfs_dquot.c
@@ -44,10 +44,9 @@
  *
  * ip->i_lock
  *   qi->qi_tree_lock
- *     qi->qi_dqlist_lock
- *       dquot->q_qlock (xfs_dqlock() and friends)
- *         dquot->q_flush (xfs_dqflock() and friends)
- *         qi->qi_lru_lock
+ *     dquot->q_qlock (xfs_dqlock() and friends)
+ *       dquot->q_flush (xfs_dqflock() and friends)
+ *       qi->qi_lru_lock
  *
  * If two dquots need to be locked the order is user before group/project,
  * otherwise by the lowest id first, see xfs_dqlock2.
@@ -729,20 +728,12 @@ restart:
         }
 
         /*
-         * Attach this dquot to this filesystem's list of all dquots,
-         * kept inside the mount structure in m_quotainfo field
-         */
-        mutex_lock(&qi->qi_dqlist_lock);
-
-        /*
          * We return a locked dquot to the caller, with a reference taken
          */
         xfs_dqlock(dqp);
         dqp->q_nrefs = 1;
 
-        list_add(&dqp->q_mplist, &qi->qi_dqlist);
         qi->qi_dquots++;
-        mutex_unlock(&qi->qi_dqlist_lock);
         mutex_unlock(&qi->qi_tree_lock);
 
  dqret:
@@ -1018,86 +1009,6 @@ xfs_dqlock2(
 }
 
 /*
- * Take a dquot out of the mount's dqlist as well as the hashlist.  This is
- * called via unmount as well as quotaoff, and the purge will always succeed.
- */
-void
-xfs_qm_dqpurge(
-        struct xfs_dquot        *dqp)
-{
-        struct xfs_mount        *mp = dqp->q_mount;
-        struct xfs_quotainfo    *qi = mp->m_quotainfo;
-
-        xfs_dqlock(dqp);
-
-        /*
-         * If we're turning off quotas, we have to make sure that, for
-         * example, we don't delete quota disk blocks while dquots are
-         * in the process of getting written to those disk blocks.
-         * This dquot might well be on AIL, and we can't leave it there
-         * if we're turning off quotas. Basically, we need this flush
-         * lock, and are willing to block on it.
-         */
-        if (!xfs_dqflock_nowait(dqp)) {
-                /*
-                 * Block on the flush lock after nudging dquot buffer,
-                 * if it is incore.
-                 */
-                xfs_dqflock_pushbuf_wait(dqp);
-        }
-
-        /*
-         * If we are turning this type of quotas off, we don't care
-         * about the dirty metadata sitting in this dquot. OTOH, if
-         * we're unmounting, we do care, so we flush it and wait.
-         */
-        if (XFS_DQ_IS_DIRTY(dqp)) {
-                int     error;
-
-                /*
-                 * We don't care about getting disk errors here. We need
-                 * to purge this dquot anyway, so we go ahead regardless.
-                 */
-                error = xfs_qm_dqflush(dqp, SYNC_WAIT);
-                if (error)
-                        xfs_warn(mp, "%s: dquot %p flush failed",
-                                __func__, dqp);
-                xfs_dqflock(dqp);
-        }
-
-        ASSERT(atomic_read(&dqp->q_pincount) == 0);
-        ASSERT(XFS_FORCED_SHUTDOWN(mp) ||
-               !(dqp->q_logitem.qli_item.li_flags & XFS_LI_IN_AIL));
-
-        xfs_dqfunlock(dqp);
-        xfs_dqunlock(dqp);
-
-        mutex_lock(&qi->qi_tree_lock);
-        radix_tree_delete(XFS_DQUOT_TREE(qi, dqp->q_core.d_flags),
-                          be32_to_cpu(dqp->q_core.d_id));
-        mutex_unlock(&qi->qi_tree_lock);
-
-        mutex_lock(&qi->qi_dqlist_lock);
-        list_del_init(&dqp->q_mplist);
-        qi->qi_dqreclaims++;
-        qi->qi_dquots--;
-        mutex_unlock(&qi->qi_dqlist_lock);
-
-        /*
-         * We move dquots to the freelist as soon as their reference count
-         * hits zero, so it really should be on the freelist here.
-         */
-        mutex_lock(&qi->qi_lru_lock);
-        ASSERT(!list_empty(&dqp->q_lru));
-        list_del_init(&dqp->q_lru);
-        qi->qi_lru_count--;
-        XFS_STATS_DEC(xs_qm_dquot_unused);
-        mutex_unlock(&qi->qi_lru_lock);
-
-        xfs_qm_dqdestroy(dqp);
-}
-
-/*
  * Give the buffer a little push if it is incore and
  * wait on the flush lock.
  */