[XFS] kill xfs_mount_init

xfs_mount_init is inlined into xfs_fs_fill_super and allocation switched
to kzalloc. Plug a leak of the mount structure for most early mount
failures. Move xfs_icsb_init_counters to as late as possible in the mount
path and make sure to undo it so that no stale hotplug cpu notifiers are
left around on mount failures.

SGI-PV: 981951
SGI-Modid: xfs-linux-melb:xfs-kern:31196a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

fs/xfs/linux-2.6/xfs_super.c

@@ -1273,10 +1273,11 @@ xfs_fs_put_super(
 	}
 
 	xfs_unmountfs(mp);
+	xfs_icsb_destroy_counters(mp);
 	xfs_close_devices(mp);
 	xfs_qmops_put(mp);
 	xfs_dmops_put(mp);
-	kmem_free(mp);
+	kfree(mp);
 }
 
 STATIC void
@@ -1733,14 +1734,20 @@ xfs_fs_fill_super(
 	struct inode		*root;
 	struct xfs_mount	*mp = NULL;
 	struct xfs_mount_args	*args;
-	int			flags = 0, error;
+	int			flags = 0, error = ENOMEM;
 
 	args = xfs_args_allocate(sb, silent);
 	if (!args)
 		return -ENOMEM;
 
-	mp = xfs_mount_init();
+	mp = kzalloc(sizeof(struct xfs_mount), GFP_KERNEL);
+	if (!mp)
+		goto out_free_args;
 
+	spin_lock_init(&mp->m_sb_lock);
+	mutex_init(&mp->m_ilock);
+	mutex_init(&mp->m_growlock);
+	atomic_set(&mp->m_active_trans, 0);
 	INIT_LIST_HEAD(&mp->m_sync_list);
 	spin_lock_init(&mp->m_sync_lock);
 	init_waitqueue_head(&mp->m_wait_single_sync_task);
@@ -1753,7 +1760,7 @@ xfs_fs_fill_super(
 
 	error = xfs_parseargs(mp, (char *)data, args, 0);
 	if (error)
-		goto fail_vfsop;
+		goto out_free_mp;
 
 	sb_min_blocksize(sb, BBSIZE);
 	sb->s_export_op = &xfs_export_operations;
@@ -1762,7 +1769,7 @@ xfs_fs_fill_super(
 
 	error = xfs_dmops_get(mp, args);
 	if (error)
-		goto fail_vfsop;
+		goto out_free_mp;
 	error = xfs_qmops_get(mp, args);
 	if (error)
 		goto out_put_dmops;
@@ -1774,6 +1781,9 @@ xfs_fs_fill_super(
 	if (error)
 		goto out_put_qmops;
 
+	if (xfs_icsb_init_counters(mp))
+		mp->m_flags |= XFS_MOUNT_NO_PERCPU_SB;
+
 	/*
 	 * Setup flags based on mount(2) options and then the superblock
 	 */
@@ -1849,12 +1859,18 @@ xfs_fs_fill_super(
 		xfs_binval(mp->m_logdev_targp);
 	if (mp->m_rtdev_targp)
 		xfs_binval(mp->m_rtdev_targp);
+ out_destroy_counters:
+	xfs_icsb_destroy_counters(mp);
 	xfs_close_devices(mp);
  out_put_qmops:
 	xfs_qmops_put(mp);
  out_put_dmops:
 	xfs_dmops_put(mp);
-	goto fail_vfsop;
+ out_free_mp:
+	kfree(mp);
+ out_free_args:
+	kfree(args);
+	return -error;
 
  fail_vnrele:
 	if (sb->s_root) {
@@ -1879,14 +1895,7 @@ xfs_fs_fill_super(
 	IRELE(mp->m_rootip);
 
 	xfs_unmountfs(mp);
-	xfs_close_devices(mp);
-	xfs_qmops_put(mp);
-	xfs_dmops_put(mp);
-	kmem_free(mp);
-
- fail_vfsop:
-	kfree(args);
-	return -error;
+	goto out_destroy_counters;
 }
 
 STATIC int

fs/xfs/xfs_mount.c

@@ -51,7 +51,6 @@ STATIC void	xfs_unmountfs_wait(xfs_mount_t *);
 
 
 #ifdef HAVE_PERCPU_SB
-STATIC void	xfs_icsb_destroy_counters(xfs_mount_t *);
 STATIC void	xfs_icsb_balance_counter(xfs_mount_t *, xfs_sb_field_t,
 						int);
 STATIC void	xfs_icsb_balance_counter_locked(xfs_mount_t *, xfs_sb_field_t,
@@ -62,7 +61,6 @@ STATIC void	xfs_icsb_disable_counter(xfs_mount_t *, xfs_sb_field_t);
 
 #else
 
-#define xfs_icsb_destroy_counters(mp)			do { } while (0)
 #define xfs_icsb_balance_counter(mp, a, b)		do { } while (0)
 #define xfs_icsb_balance_counter_locked(mp, a, b)	do { } while (0)
 #define xfs_icsb_modify_counters(mp, a, b, c)		do { } while (0)
@@ -124,34 +122,12 @@ static const struct {
     { sizeof(xfs_sb_t),			 0 }
 };
 
-/*
- * Return a pointer to an initialized xfs_mount structure.
- */
-xfs_mount_t *
-xfs_mount_init(void)
-{
-	xfs_mount_t *mp;
-
-	mp = kmem_zalloc(sizeof(xfs_mount_t), KM_SLEEP);
-
-	if (xfs_icsb_init_counters(mp)) {
-		mp->m_flags |= XFS_MOUNT_NO_PERCPU_SB;
-	}
-
-	spin_lock_init(&mp->m_sb_lock);
-	mutex_init(&mp->m_ilock);
-	mutex_init(&mp->m_growlock);
-	atomic_set(&mp->m_active_trans, 0);
-
-	return mp;
-}
-
 /*
  * Free up the resources associated with a mount structure.  Assume that
  * the structure was initially zeroed, so we can tell which fields got
  * initialized.
  */
-void
+STATIC void
 xfs_mount_free(
 	xfs_mount_t	*mp)
 {
@@ -177,8 +153,6 @@ xfs_mount_free(
 		kmem_free(mp->m_rtname);
 	if (mp->m_logname != NULL)
 		kmem_free(mp->m_logname);
-
-	xfs_icsb_destroy_counters(mp);
 }
 
 /*
@@ -2093,7 +2067,7 @@ xfs_icsb_reinit_counters(
 	xfs_icsb_unlock(mp);
 }
 
-STATIC void
+void
 xfs_icsb_destroy_counters(
 	xfs_mount_t	*mp)
 {

fs/xfs/xfs_mount.h

@@ -210,12 +210,14 @@ typedef struct xfs_icsb_cnts {
 
 extern int	xfs_icsb_init_counters(struct xfs_mount *);
 extern void	xfs_icsb_reinit_counters(struct xfs_mount *);
+extern void	xfs_icsb_destroy_counters(struct xfs_mount *);
 extern void	xfs_icsb_sync_counters(struct xfs_mount *, int);
 extern void	xfs_icsb_sync_counters_locked(struct xfs_mount *, int);
 
 #else
-#define xfs_icsb_init_counters(mp)	(0)
-#define xfs_icsb_reinit_counters(mp)	do { } while (0)
+#define xfs_icsb_init_counters(mp)		(0)
+#define xfs_icsb_destroy_counters(mp)		do { } while (0)
+#define xfs_icsb_reinit_counters(mp)		do { } while (0)
 #define xfs_icsb_sync_counters(mp, flags)	do { } while (0)
 #define xfs_icsb_sync_counters_locked(mp, flags) do { } while (0)
 #endif
@@ -511,10 +513,8 @@ typedef struct xfs_mod_sb {
 #define	XFS_MOUNT_ILOCK(mp)	mutex_lock(&((mp)->m_ilock))
 #define	XFS_MOUNT_IUNLOCK(mp)	mutex_unlock(&((mp)->m_ilock))
 
-extern xfs_mount_t *xfs_mount_init(void);
 extern void	xfs_mod_sb(xfs_trans_t *, __int64_t);
 extern int	xfs_log_sbcount(xfs_mount_t *, uint);
-extern void	xfs_mount_free(xfs_mount_t *mp);
 extern int	xfs_mountfs(xfs_mount_t *mp, int);
 extern void	xfs_mountfs_check_barriers(xfs_mount_t *mp);