[PATCH 2/4] xfs: add xfs_set_inode32()

[Carlos Maiolino]

xfs_set_inode32() can be used to enable inode32 allocation mode. this will
reduce the amount of duplicated code needed to mount/remount a filesystem with
inode32 option.
This patch also enable xfs_set_inode64() to return a xfs_agnumber_t value to
also be used during mount/remount, instead of duplicate code

Signed-off-by: Carlos Maiolino <cmaiolino at redhat.com>
---
 fs/xfs/xfs_super.c | 102 ++++++++++++++++++++++++++++++++++++++++-------------
 fs/xfs/xfs_super.h |   2 ++
 2 files changed, 80 insertions(+), 24 deletions(-)

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index b1aa2db..2d7a0d9 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -598,6 +598,84 @@ xfs_max_file_offset(
 	return (((__uint64_t)pagefactor) << bitshift) - 1;
 }
 
+xfs_agnumber_t
+xfs_set_inode64(struct xfs_mount *mp)
+{
+	xfs_agnumber_t index = 0;
+
+	for (index = 0; index < mp->m_sb.sb_agcount; index++) {
+		struct xfs_perag	*pag;
+
+		pag = xfs_perag_get(mp, index);
+		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);
+	mp->m_maxagi = index;
+
+	return index;
+}
+
+xfs_agnumber_t
+xfs_set_inode32(struct xfs_mount *mp)
+{
+	xfs_agnumber_t	index;
+	xfs_agnumber_t	i = 0;
+	xfs_sb_t	*sbp = &mp->m_sb;
+	xfs_agnumber_t	max_metadata;
+	xfs_agino_t	agino =	XFS_OFFBNO_TO_AGINO(mp, sbp->sb_agblocks -1, 0);
+	xfs_ino_t	ino = XFS_AGINO_TO_INO(mp, sbp->sb_agcount -1, agino);
+	xfs_perag_t	*pag;
+
+	/* Calculate how much should be reserved for inodes to meet
+	 * the max inode percentage.
+	 */
+	if (mp->m_maxicount) {
+		__uint64_t	icount;
+
+		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
+		do_div(icount, 100);
+		icount += sbp->sb_agblocks - 1;
+		do_div(icount, sbp->sb_agblocks);
+		max_metadata = icount;
+	} else {
+		max_metadata = sbp->sb_agcount;
+	}
+
+	for (index = 0; index < sbp->sb_agcount; index++) {
+		ino = XFS_AGINO_TO_INO(mp, index, agino);
+
+		if (ino > XFS_MAXINUMBER_32) {
+			i++;
+			pag = xfs_perag_get(mp, index);
+			pag->pagi_inodeok = 0;
+			pag->pagf_metadata = 1;
+			xfs_perag_put(pag);
+			continue;
+		}
+
+		pag = xfs_perag_get(mp, index);
+		pag->pagi_inodeok = 1;
+		if (index < max_metadata)
+			pag->pagf_metadata = 1;
+
+		xfs_perag_put(pag);
+	}
+
+	index -= i;
+	mp->m_flags |= (XFS_MOUNT_32BITINODES |
+			XFS_MOUNT_SMALL_INUMS);
+	return index;
+}
+
 STATIC int
 xfs_blkdev_get(
 	xfs_mount_t		*mp,
@@ -1037,30 +1115,6 @@ xfs_restore_resvblks(struct xfs_mount *mp)
 	xfs_reserve_blocks(mp, &resblks, NULL);
 }
 
-STATIC void
-xfs_set_inode64(struct xfs_mount *mp)
-{
-	int i = 0;
-
-	for (i = 0; i < mp->m_sb.sb_agcount; i++) {
-		struct xfs_perag	*pag;
-
-		pag = xfs_perag_get(mp, i);
-		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);
-	mp->m_maxagi = i;
-}
-
 STATIC int
 xfs_fs_remount(
 	struct super_block	*sb,
diff --git a/fs/xfs/xfs_super.h b/fs/xfs/xfs_super.h
index 09b0c26..9de4a92 100644
--- a/fs/xfs/xfs_super.h
+++ b/fs/xfs/xfs_super.h
@@ -75,6 +75,8 @@ struct block_device;
 extern __uint64_t xfs_max_file_offset(unsigned int);
 
 extern void xfs_blkdev_issue_flush(struct xfs_buftarg *);
+extern xfs_agnumber_t xfs_set_inode32(struct xfs_mount *);
+extern xfs_agnumber_t xfs_set_inode64(struct xfs_mount *);
 
 extern const struct export_operations xfs_export_operations;
 extern const struct xattr_handler *xfs_xattr_handlers[];
-- 
1.7.11.4