1 files changed, 21 insertions, 21 deletions

diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
index a13919a6a364..37a6f62c57b6 100644
--- a/fs/xfs/xfs_fsops.c
+++ b/fs/xfs/xfs_fsops.c
@@ -167,27 +167,14 @@ xfs_growfs_data_private(
         }
         new = nb - mp->m_sb.sb_dblocks;
         oagcount = mp->m_sb.sb_agcount;
-        if (nagcount > oagcount) {
-                void *new_perag, *old_perag;
-
-                xfs_filestream_flush(mp);
-
-                new_perag = kmem_zalloc(sizeof(xfs_perag_t) * nagcount,
-                                        KM_MAYFAIL);
-                if (!new_perag)
-                        return XFS_ERROR(ENOMEM);
-
-                down_write(&mp->m_peraglock);
-                memcpy(new_perag, mp->m_perag, sizeof(xfs_perag_t) * oagcount);
-                old_perag = mp->m_perag;
-                mp->m_perag = new_perag;
-
-                mp->m_flags |= XFS_MOUNT_32BITINODES;
-                nagimax = xfs_initialize_perag(mp, nagcount);
-                up_write(&mp->m_peraglock);
 
-                kmem_free(old_perag);
+        /* allocate the new per-ag structures */
+        if (nagcount > oagcount) {
+                error = xfs_initialize_perag(mp, nagcount, &nagimax);
+                if (error)
+                        return error;
         }
+
         tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFS);
         tp->t_flags |= XFS_TRANS_RESERVE;
         if ((error = xfs_trans_reserve(tp, XFS_GROWFS_SPACE_RES(mp),
@@ -196,6 +183,11 @@ xfs_growfs_data_private(
                 return error;
         }
 
+        /*
+         * Write new AG headers to disk. Non-transactional, but written
+         * synchronously so they are completed prior to the growfs transaction
+         * being logged.
+         */
         nfree = 0;
         for (agno = nagcount - 1; agno >= oagcount; agno--, new -= agsize) {
                 /*
@@ -359,6 +351,12 @@ xfs_growfs_data_private(
                         goto error0;
                 }
         }
+
+        /*
+         * Update changed superblock fields transactionally. These are not
+         * seen by the rest of the world until the transaction commit applies
+         * them atomically to the superblock.
+         */
         if (nagcount > oagcount)
                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_AGCOUNT, nagcount - oagcount);
         if (nb > mp->m_sb.sb_dblocks)
@@ -369,9 +367,9 @@ xfs_growfs_data_private(
         if (dpct)
                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IMAXPCT, dpct);
         error = xfs_trans_commit(tp, 0);
-        if (error) {
+        if (error)
                 return error;
-        }
+
         /* New allocation groups fully initialized, so update mount struct */
         if (nagimax)
                 mp->m_maxagi = nagimax;
@@ -381,6 +379,8 @@ xfs_growfs_data_private(
                 mp->m_maxicount = icount << mp->m_sb.sb_inopblog;
         } else
                 mp->m_maxicount = 0;
+
+        /* update secondary superblocks. */
         for (agno = 1; agno < nagcount; agno++) {
                 error = xfs_read_buf(mp, mp->m_ddev_targp,
                                   XFS_AGB_TO_DADDR(mp, agno, XFS_SB_BLOCK(mp)),