xfs: fix up inode32/64 (re)mount handling
inode32/inode64 allocator behavior with respect to mount, remount
and growfs is a little tricky.
The inode32 mount option should only enable the inode32 allocator
heuristics if the filesystem is large enough for 64-bit inodes to
exist. Today, it has this behavior on the initial mount, but a
remount with inode32 unconditionally changes the allocation
heuristics, even for a small fs.
Also, an inode32 mounted small filesystem should transition to the
inode32 allocator if the filesystem is subsequently grown to a
sufficient size. Today that does not happen.
This patch consolidates xfs_set_inode32 and xfs_set_inode64 into a
single new function, and moves the "is the maximum inode number big
enough to matter" test into that function, so it doesn't rely on the
caller to get it right - which remount did not do, previously.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 8dd7d16..d85087b 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -580,23 +580,35 @@
}
/*
- * xfs_set_inode32() and xfs_set_inode64() are passed an agcount
- * because in the growfs case, mp->m_sb.sb_agcount is not updated
- * yet to the potentially higher ag count.
+ * Set parameters for inode allocation heuristics, taking into account
+ * filesystem size and inode32/inode64 mount options; i.e. specifically
+ * whether or not XFS_MOUNT_SMALL_INUMS is set.
+ *
+ * Inode allocation patterns are altered only if inode32 is requested
+ * (XFS_MOUNT_SMALL_INUMS), and the filesystem is sufficiently large.
+ * If altered, XFS_MOUNT_32BITINODES is set as well.
+ *
+ * An agcount independent of that in the mount structure is provided
+ * because in the growfs case, mp->m_sb.sb_agcount is not yet updated
+ * to the potentially higher ag count.
+ *
+ * Returns the maximum AG index which may contain inodes.
*/
xfs_agnumber_t
-xfs_set_inode32(struct xfs_mount *mp, xfs_agnumber_t agcount)
+xfs_set_inode_alloc(
+ struct xfs_mount *mp,
+ xfs_agnumber_t agcount)
{
- xfs_agnumber_t index = 0;
+ xfs_agnumber_t index;
xfs_agnumber_t maxagi = 0;
xfs_sb_t *sbp = &mp->m_sb;
xfs_agnumber_t max_metadata;
xfs_agino_t agino;
xfs_ino_t ino;
- xfs_perag_t *pag;
- /* Calculate how much should be reserved for inodes to meet
- * the max inode percentage.
+ /*
+ * Calculate how much should be reserved for inodes to meet
+ * the max inode percentage. Used only for inode32.
*/
if (mp->m_maxicount) {
__uint64_t icount;
@@ -610,54 +622,48 @@
max_metadata = agcount;
}
+ /* Get the last possible inode in the filesystem */
agino = XFS_OFFBNO_TO_AGINO(mp, sbp->sb_agblocks - 1, 0);
+ ino = XFS_AGINO_TO_INO(mp, agcount - 1, agino);
- for (index = 0; index < agcount; index++) {
- ino = XFS_AGINO_TO_INO(mp, index, agino);
-
- if (ino > XFS_MAXINUMBER_32) {
- pag = xfs_perag_get(mp, index);
- pag->pagi_inodeok = 0;
- pag->pagf_metadata = 0;
- xfs_perag_put(pag);
- continue;
- }
-
- pag = xfs_perag_get(mp, index);
- pag->pagi_inodeok = 1;
- maxagi++;
- if (index < max_metadata)
- pag->pagf_metadata = 1;
- xfs_perag_put(pag);
- }
- mp->m_flags |= (XFS_MOUNT_32BITINODES |
- XFS_MOUNT_SMALL_INUMS);
-
- return maxagi;
-}
-
-xfs_agnumber_t
-xfs_set_inode64(struct xfs_mount *mp, xfs_agnumber_t agcount)
-{
- xfs_agnumber_t index = 0;
+ /*
+ * If user asked for no more than 32-bit inodes, and the fs is
+ * sufficiently large, set XFS_MOUNT_32BITINODES if we must alter
+ * the allocator to accommodate the request.
+ */
+ if ((mp->m_flags & XFS_MOUNT_SMALL_INUMS) && ino > XFS_MAXINUMBER_32)
+ mp->m_flags |= XFS_MOUNT_32BITINODES;
+ else
+ mp->m_flags &= ~XFS_MOUNT_32BITINODES;
for (index = 0; index < agcount; index++) {
struct xfs_perag *pag;
+ ino = XFS_AGINO_TO_INO(mp, index, agino);
+
pag = xfs_perag_get(mp, index);
- pag->pagi_inodeok = 1;
- pag->pagf_metadata = 0;
+
+ if (mp->m_flags & XFS_MOUNT_32BITINODES) {
+ if (ino > XFS_MAXINUMBER_32) {
+ pag->pagi_inodeok = 0;
+ pag->pagf_metadata = 0;
+ } else {
+ pag->pagi_inodeok = 1;
+ maxagi++;
+ if (index < max_metadata)
+ pag->pagf_metadata = 1;
+ else
+ pag->pagf_metadata = 0;
+ }
+ } else {
+ pag->pagi_inodeok = 1;
+ pag->pagf_metadata = 0;
+ }
+
xfs_perag_put(pag);
}
- /* There is no need for lock protection on m_flags,
- * the rw_semaphore of the VFS superblock is locked
- * during mount/umount/remount operations, so this is
- * enough to avoid concurency on the m_flags field
- */
- mp->m_flags &= ~(XFS_MOUNT_32BITINODES |
- XFS_MOUNT_SMALL_INUMS);
- return index;
+ return (mp->m_flags & XFS_MOUNT_32BITINODES) ? maxagi : agcount;
}
STATIC int
@@ -1227,10 +1233,12 @@
mp->m_flags &= ~XFS_MOUNT_BARRIER;
break;
case Opt_inode64:
- mp->m_maxagi = xfs_set_inode64(mp, sbp->sb_agcount);
+ mp->m_flags &= ~XFS_MOUNT_SMALL_INUMS;
+ mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount);
break;
case Opt_inode32:
- mp->m_maxagi = xfs_set_inode32(mp, sbp->sb_agcount);
+ mp->m_flags |= XFS_MOUNT_SMALL_INUMS;
+ mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount);
break;
default:
/*