[XFS] Traverse inode trees when releasing dquots

Make releasing all inode dquots traverse the per-ag inode radix trees
rather than the mount inode list. This removes another user of the mount
inode list.

Version 3 o fix comment relating to avoiding trying to release the

quota inodes and those in reclaim.

Version 2 o add comment explaining use of gang lookups for a single inode
o use IRELE, not VN_RELE o move check for ag initialisation to caller.

SGI-PV: 988139

SGI-Modid: xfs-linux-melb:xfs-kern:32291a

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

1 files changed, 59 insertions, 68 deletions

diff --git a/fs/xfs/quota/xfs_qm_syscalls.c b/fs/xfs/quota/xfs_qm_syscalls.c
index 1a3b803dfa55..26152b9ccc6f 100644
--- a/fs/xfs/quota/xfs_qm_syscalls.c
+++ b/fs/xfs/quota/xfs_qm_syscalls.c
@@ -1022,101 +1022,92 @@ xfs_qm_export_flags(
 
 
 /*
- * Go thru all the inodes in the file system, releasing their dquots.
- * Note that the mount structure gets modified to indicate that quotas are off
- * AFTER this, in the case of quotaoff. This also gets called from
- * xfs_rootumount.
+ * Release all the dquots on the inodes in an AG.
  */
-void
-xfs_qm_dqrele_all_inodes(
-        struct xfs_mount *mp,
-        uint             flags)
+STATIC void
+xfs_qm_dqrele_inodes_ag(
+        xfs_mount_t     *mp,
+        int             ag,
+        uint            flags)
 {
-        xfs_inode_t     *ip, *topino;
-        uint            ireclaims;
-        struct inode    *vp;
-        boolean_t       vnode_refd;
+        xfs_inode_t     *ip = NULL;
+        struct inode    *vp = NULL;
+        xfs_perag_t     *pag = &mp->m_perag[ag];
+        int             first_index = 0;
+        int             nr_found;
 
-        ASSERT(mp->m_quotainfo);
-
-        XFS_MOUNT_ILOCK(mp);
-again:
-        ip = mp->m_inodes;
-        if (ip == NULL) {
-                XFS_MOUNT_IUNLOCK(mp);
-                return;
-        }
         do {
-                /* Skip markers inserted by xfs_sync */
-                if (ip->i_mount == NULL) {
-                        ip = ip->i_mnext;
-                        continue;
-                }
-                /* Root inode, rbmip and rsumip have associated blocks */
-                if (ip == XFS_QI_UQIP(mp) || ip == XFS_QI_GQIP(mp)) {
-                        ASSERT(ip->i_udquot == NULL);
-                        ASSERT(ip->i_gdquot == NULL);
-                        ip = ip->i_mnext;
-                        continue;
+                boolean_t       vnode_refd = B_FALSE;
+
+                /*
+                 * use a gang lookup to find the next inode in the tree
+                 * as the tree is sparse and a gang lookup walks to find
+                 * the number of objects requested.
+                 */
+                read_lock(&pag->pag_ici_lock);
+                nr_found = radix_tree_gang_lookup(&pag->pag_ici_root,
+                                (void**)&ip, first_index, 1);
+
+                if (!nr_found) {
+                        read_unlock(&pag->pag_ici_lock);
+                        break;
                 }
+
+                /* update the index for the next lookup */
+                first_index = XFS_INO_TO_AGINO(mp, ip->i_ino + 1);
+
+                /* skip quota inodes and those in reclaim */
                 vp = VFS_I(ip);
-                if (!vp) {
+                if (!vp || ip == XFS_QI_UQIP(mp) || ip == XFS_QI_GQIP(mp)) {
                         ASSERT(ip->i_udquot == NULL);
                         ASSERT(ip->i_gdquot == NULL);
-                        ip = ip->i_mnext;
+                        read_unlock(&pag->pag_ici_lock);
                         continue;
                 }
-                vnode_refd = B_FALSE;
                 if (xfs_ilock_nowait(ip, XFS_ILOCK_EXCL) == 0) {
-                        ireclaims = mp->m_ireclaims;
-                        topino = mp->m_inodes;
                         vp = vn_grab(vp);
+                        read_unlock(&pag->pag_ici_lock);
                         if (!vp)
-                                goto again;
-
-                        XFS_MOUNT_IUNLOCK(mp);
-                        /* XXX restart limit ? */
-                        xfs_ilock(ip, XFS_ILOCK_EXCL);
+                                continue;
                         vnode_refd = B_TRUE;
+                        xfs_ilock(ip, XFS_ILOCK_EXCL);
                 } else {
-                        ireclaims = mp->m_ireclaims;
-                        topino = mp->m_inodes;
-                        XFS_MOUNT_IUNLOCK(mp);
+                        read_unlock(&pag->pag_ici_lock);
                 }
-
-                /*
-                 * We don't keep the mountlock across the dqrele() call,
-                 * since it can take a while..
-                 */
                 if ((flags & XFS_UQUOTA_ACCT) && ip->i_udquot) {
                         xfs_qm_dqrele(ip->i_udquot);
                         ip->i_udquot = NULL;
                 }
-                if (flags & (XFS_PQUOTA_ACCT|XFS_GQUOTA_ACCT) && ip->i_gdquot) {
+                if (flags & (XFS_PQUOTA_ACCT|XFS_GQUOTA_ACCT) &&
+                    ip->i_gdquot) {
                         xfs_qm_dqrele(ip->i_gdquot);
                         ip->i_gdquot = NULL;
                 }
                 xfs_iunlock(ip, XFS_ILOCK_EXCL);
-                /*
-                 * Wait until we've dropped the ilock and mountlock to
-                 * do the vn_rele. Or be condemned to an eternity in the
-                 * inactive code in hell.
-                 */
                 if (vnode_refd)
                         IRELE(ip);
-                XFS_MOUNT_ILOCK(mp);
-                /*
-                 * If an inode was inserted or removed, we gotta
-                 * start over again.
-                 */
-                if (topino != mp->m_inodes || mp->m_ireclaims != ireclaims) {
-                        /* XXX use a sentinel */
-                        goto again;
-                }
-                ip = ip->i_mnext;
-        } while (ip != mp->m_inodes);
+        } while (nr_found);
+}
 
-        XFS_MOUNT_IUNLOCK(mp);
+/*
+ * Go thru all the inodes in the file system, releasing their dquots.
+ * Note that the mount structure gets modified to indicate that quotas are off
+ * AFTER this, in the case of quotaoff. This also gets called from
+ * xfs_rootumount.
+ */
+void
+xfs_qm_dqrele_all_inodes(
+        struct xfs_mount *mp,
+        uint             flags)
+{
+        int             i;
+
+        ASSERT(mp->m_quotainfo);
+        for (i = 0; i < mp->m_sb.sb_agcount; i++) {
+                if (!mp->m_perag[i].pag_ici_init)
+                        continue;
+                xfs_qm_dqrele_inodes_ag(mp, i, flags);
+        }
 }
 
 /*------------------------------------------------------------------------*/