1 files changed, 48 insertions, 15 deletions

diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index 9055b60730d0..c04dd83cb57c 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -209,13 +209,16 @@ STATIC void
 xfs_free_perag(
         xfs_mount_t     *mp)
 {
-        if (mp->m_perag) {
-                int     agno;
+        xfs_agnumber_t  agno;
+        struct xfs_perag *pag;
 
-                for (agno = 0; agno < mp->m_maxagi; agno++)
-                        if (mp->m_perag[agno].pagb_list)
-                                kmem_free(mp->m_perag[agno].pagb_list);
-                kmem_free(mp->m_perag);
+        for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
+                spin_lock(&mp->m_perag_lock);
+                pag = radix_tree_delete(&mp->m_perag_tree, agno);
+                spin_unlock(&mp->m_perag_lock);
+                ASSERT(pag);
+                kmem_free(pag->pagb_list);
+                kmem_free(pag);
         }
 }
 
@@ -389,10 +392,11 @@ xfs_initialize_perag_icache(
         }
 }
 
-xfs_agnumber_t
+int
 xfs_initialize_perag(
         xfs_mount_t     *mp,
-        xfs_agnumber_t  agcount)
+        xfs_agnumber_t  agcount,
+        xfs_agnumber_t  *maxagi)
 {
         xfs_agnumber_t  index, max_metadata;
         xfs_perag_t     *pag;
@@ -405,6 +409,33 @@ xfs_initialize_perag(
         agino = XFS_OFFBNO_TO_AGINO(mp, sbp->sb_agblocks - 1, 0);
         ino = XFS_AGINO_TO_INO(mp, agcount - 1, agino);
 
+        /*
+         * Walk the current per-ag tree so we don't try to initialise AGs
+         * that already exist (growfs case). Allocate and insert all the
+         * AGs we don't find ready for initialisation.
+         */
+        for (index = 0; index < agcount; index++) {
+                pag = xfs_perag_get(mp, index);
+                if (pag) {
+                        xfs_perag_put(pag);
+                        continue;
+                }
+                pag = kmem_zalloc(sizeof(*pag), KM_MAYFAIL);
+                if (!pag)
+                        return -ENOMEM;
+                if (radix_tree_preload(GFP_NOFS))
+                        return -ENOMEM;
+                spin_lock(&mp->m_perag_lock);
+                if (radix_tree_insert(&mp->m_perag_tree, index, pag)) {
+                        BUG();
+                        spin_unlock(&mp->m_perag_lock);
+                        kmem_free(pag);
+                        return -EEXIST;
+                }
+                spin_unlock(&mp->m_perag_lock);
+                radix_tree_preload_end();
+        }
+
         /* Clear the mount flag if no inode can overflow 32 bits
          * on this filesystem, or if specifically requested..
          */
@@ -454,7 +485,9 @@ xfs_initialize_perag(
                         xfs_perag_put(pag);
                 }
         }
-        return index;
+        if (maxagi)
+                *maxagi = index;
+        return 0;
 }
 
 void
@@ -1155,13 +1188,13 @@ xfs_mountfs(
         /*
          * Allocate and initialize the per-ag data.
          */
-        init_rwsem(&mp->m_peraglock);
-        mp->m_perag = kmem_zalloc(sbp->sb_agcount * sizeof(xfs_perag_t),
-                                  KM_MAYFAIL);
-        if (!mp->m_perag)
+        spin_lock_init(&mp->m_perag_lock);
+        INIT_RADIX_TREE(&mp->m_perag_tree, GFP_NOFS);
+        error = xfs_initialize_perag(mp, sbp->sb_agcount, &mp->m_maxagi);
+        if (error) {
+                cmn_err(CE_WARN, "XFS: Failed per-ag init: %d", error);
                 goto out_remove_uuid;
-
-        mp->m_maxagi = xfs_initialize_perag(mp, sbp->sb_agcount);
+        }
 
         if (!sbp->sb_logblocks) {
                 cmn_err(CE_WARN, "XFS: no log defined");