1 files changed, 29 insertions, 26 deletions

diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 1cfeec56df91..4e5bf3fbf782 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -1137,11 +1137,11 @@ static int check_free_space(struct ubifs_info *c)
  */
 static int mount_ubifs(struct ubifs_info *c)
 {
-        struct super_block *sb = c->vfs_sb;
-        int err, mounted_read_only = (sb->s_flags & MS_RDONLY);
+        int err;
         long long x;
         size_t sz;
 
+        c->ro_mount = !!(c->vfs_sb->s_flags & MS_RDONLY);
         err = init_constants_early(c);
         if (err)
                 return err;
@@ -1154,7 +1154,7 @@ static int mount_ubifs(struct ubifs_info *c)
         if (err)
                 goto out_free;
 
-        if (c->empty && (mounted_read_only || c->ro_media)) {
+        if (c->empty && (c->ro_mount || c->ro_media)) {
                 /*
                  * This UBI volume is empty, and read-only, or the file system
                  * is mounted read-only - we cannot format it.
@@ -1165,7 +1165,7 @@ static int mount_ubifs(struct ubifs_info *c)
                 goto out_free;
         }
 
-        if (c->ro_media && !mounted_read_only) {
+        if (c->ro_media && !c->ro_mount) {
                 ubifs_err("cannot mount read-write - read-only media");
                 err = -EROFS;
                 goto out_free;
@@ -1185,7 +1185,7 @@ static int mount_ubifs(struct ubifs_info *c)
         if (!c->sbuf)
                 goto out_free;
 
-        if (!mounted_read_only) {
+        if (!c->ro_mount) {
                 c->ileb_buf = vmalloc(c->leb_size);
                 if (!c->ileb_buf)
                         goto out_free;
@@ -1228,7 +1228,7 @@ static int mount_ubifs(struct ubifs_info *c)
         }
 
         sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num, c->vi.vol_id);
-        if (!mounted_read_only) {
+        if (!c->ro_mount) {
                 err = alloc_wbufs(c);
                 if (err)
                         goto out_cbuf;
@@ -1254,12 +1254,12 @@ static int mount_ubifs(struct ubifs_info *c)
         if ((c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY)) != 0) {
                 ubifs_msg("recovery needed");
                 c->need_recovery = 1;
-                if (!mounted_read_only) {
+                if (!c->ro_mount) {
                         err = ubifs_recover_inl_heads(c, c->sbuf);
                         if (err)
                                 goto out_master;
                 }
-        } else if (!mounted_read_only) {
+        } else if (!c->ro_mount) {
                 /*
                  * Set the "dirty" flag so that if we reboot uncleanly we
                  * will notice this immediately on the next mount.
@@ -1270,7 +1270,7 @@ static int mount_ubifs(struct ubifs_info *c)
                         goto out_master;
         }
 
-        err = ubifs_lpt_init(c, 1, !mounted_read_only);
+        err = ubifs_lpt_init(c, 1, !c->ro_mount);
         if (err)
                 goto out_lpt;
 
@@ -1285,11 +1285,11 @@ static int mount_ubifs(struct ubifs_info *c)
         /* Calculate 'min_idx_lebs' after journal replay */
         c->min_idx_lebs = ubifs_calc_min_idx_lebs(c);
 
-        err = ubifs_mount_orphans(c, c->need_recovery, mounted_read_only);
+        err = ubifs_mount_orphans(c, c->need_recovery, c->ro_mount);
         if (err)
                 goto out_orphans;
 
-        if (!mounted_read_only) {
+        if (!c->ro_mount) {
                 int lnum;
 
                 err = check_free_space(c);
@@ -1351,7 +1351,7 @@ static int mount_ubifs(struct ubifs_info *c)
         spin_unlock(&ubifs_infos_lock);
 
         if (c->need_recovery) {
-                if (mounted_read_only)
+                if (c->ro_mount)
                         ubifs_msg("recovery deferred");
                 else {
                         c->need_recovery = 0;
@@ -1378,7 +1378,7 @@ static int mount_ubifs(struct ubifs_info *c)
 
         ubifs_msg("mounted UBI device %d, volume %d, name \"%s\"",
                   c->vi.ubi_num, c->vi.vol_id, c->vi.name);
-        if (mounted_read_only)
+        if (c->ro_mount)
                 ubifs_msg("mounted read-only");
         x = (long long)c->main_lebs * c->leb_size;
         ubifs_msg("file system size:   %lld bytes (%lld KiB, %lld MiB, %d "
@@ -1640,7 +1640,7 @@ static int ubifs_remount_rw(struct ubifs_info *c)
         }
 
         dbg_gen("re-mounted read-write");
-        c->vfs_sb->s_flags &= ~MS_RDONLY;
+        c->ro_mount = 0;
         c->remounting_rw = 0;
         c->always_chk_crc = 0;
         err = dbg_check_space_info(c);
@@ -1676,7 +1676,7 @@ static void ubifs_remount_ro(struct ubifs_info *c)
         int i, err;
 
         ubifs_assert(!c->need_recovery);
-        ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY));
+        ubifs_assert(!c->ro_mount);
 
         mutex_lock(&c->umount_mutex);
         if (c->bgt) {
@@ -1704,6 +1704,7 @@ static void ubifs_remount_ro(struct ubifs_info *c)
         vfree(c->ileb_buf);
         c->ileb_buf = NULL;
         ubifs_lpt_free(c, 1);
+        c->ro_mount = 1;
         err = dbg_check_space_info(c);
         if (err)
                 ubifs_ro_mode(c, err);
@@ -1735,7 +1736,7 @@ static void ubifs_put_super(struct super_block *sb)
          * the mutex is locked.
          */
         mutex_lock(&c->umount_mutex);
-        if (!(c->vfs_sb->s_flags & MS_RDONLY)) {
+        if (!c->ro_mount) {
                 /*
                  * First of all kill the background thread to make sure it does
                  * not interfere with un-mounting and freeing resources.
@@ -1745,23 +1746,23 @@ static void ubifs_put_super(struct super_block *sb)
                         c->bgt = NULL;
                 }
 
-                /* Synchronize write-buffers */
-                if (c->jheads)
-                        for (i = 0; i < c->jhead_cnt; i++)
-                                ubifs_wbuf_sync(&c->jheads[i].wbuf);
-
                 /*
                  * On fatal errors c->ro_error is set to 1, in which case we do
                  * not write the master node.
                  */
                 if (!c->ro_error) {
+                        int err;
+
+                        /* Synchronize write-buffers */
+                        if (c->jheads)
+                                for (i = 0; i < c->jhead_cnt; i++)
+                                        ubifs_wbuf_sync(&c->jheads[i].wbuf);
+
                         /*
                          * We are being cleanly unmounted which means the
                          * orphans were killed - indicate this in the master
                          * node. Also save the reserved GC LEB number.
                          */
-                        int err;
-
                         c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
                         c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
                         c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
@@ -1797,7 +1798,7 @@ static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
                 return err;
         }
 
-        if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
+        if (c->ro_mount && !(*flags & MS_RDONLY)) {
                 if (c->ro_error) {
                         ubifs_msg("cannot re-mount R/W due to prior errors");
                         return -EROFS;
@@ -1809,7 +1810,7 @@ static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
                 err = ubifs_remount_rw(c);
                 if (err)
                         return err;
-        } else if (!(sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY)) {
+        } else if (!c->ro_mount && (*flags & MS_RDONLY)) {
                 if (c->ro_error) {
                         ubifs_msg("cannot re-mount R/O due to prior errors");
                         return -EROFS;
@@ -2068,9 +2069,11 @@ static int ubifs_get_sb(struct file_system_type *fs_type, int flags,
         }
 
         if (sb->s_root) {
+                struct ubifs_info *c1 = sb->s_fs_info;
+
                 /* A new mount point for already mounted UBIFS */
                 dbg_gen("this ubi volume is already mounted");
-                if ((flags ^ sb->s_flags) & MS_RDONLY) {
+                if (!!(flags & MS_RDONLY) != c1->ro_mount) {
                         err = -EBUSY;
                         goto out_deact;
                 }