[PATCH] propagate mode through open_bdev_excl/close_bdev_excl

replace open_bdev_excl/close_bdev_excl with variants taking fmode_t.
superblock gets the value used to mount it stored in sb->s_mode

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

6 files changed, 31 insertions, 24 deletions

diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c
index 91fbba767635..8c295f40d2ac 100644
--- a/drivers/mtd/devices/block2mtd.c
+++ b/drivers/mtd/devices/block2mtd.c
@@ -224,7 +224,7 @@ static void block2mtd_free_device(struct block2mtd_dev *dev)
         if (dev->blkdev) {
                 invalidate_mapping_pages(dev->blkdev->bd_inode->i_mapping,
                                         0, -1);
-                close_bdev_excl(dev->blkdev);
+                close_bdev_exclusive(dev->blkdev, FMODE_READ|FMODE_WRITE);
         }
 
         kfree(dev);
@@ -246,7 +246,7 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size)
                 return NULL;
 
         /* Get a handle on the device */
-        bdev = open_bdev_excl(devname, O_RDWR, NULL);
+        bdev = open_bdev_exclusive(devname, FMODE_READ|FMODE_WRITE, NULL);
 #ifndef MODULE
         if (IS_ERR(bdev)) {
 
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 05131baf3cf8..4b595904cefd 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1309,32 +1309,29 @@ fail:
 EXPORT_SYMBOL(lookup_bdev);
 
 /**
- * open_bdev_excl  -  open a block device by name and set it up for use
+ * open_bdev_exclusive  -  open a block device by name and set it up for use
  *
  * @path:       special file representing the block device
- * @flags:      %MS_RDONLY for opening read-only
+ * @mode:       FMODE_... combination to pass be used
  * @holder:     owner for exclusion
  *
  * Open the blockdevice described by the special file at @path, claim it
  * for the @holder.
  */
-struct block_device *open_bdev_excl(const char *path, int flags, void *holder)
+struct block_device *open_bdev_exclusive(const char *path, fmode_t mode, void *holder)
 {
         struct block_device *bdev;
-        fmode_t mode = FMODE_READ;
         int error = 0;
 
         bdev = lookup_bdev(path);
         if (IS_ERR(bdev))
                 return bdev;
 
-        if (!(flags & MS_RDONLY))
-                mode |= FMODE_WRITE;
         error = blkdev_get(bdev, mode, 0);
         if (error)
                 return ERR_PTR(error);
         error = -EACCES;
-        if (!(flags & MS_RDONLY) && bdev_read_only(bdev))
+        if ((mode & FMODE_WRITE) && bdev_read_only(bdev))
                 goto blkdev_put;
         error = bd_claim(bdev, holder);
         if (error)
@@ -1347,22 +1344,23 @@ blkdev_put:
         return ERR_PTR(error);
 }
 
-EXPORT_SYMBOL(open_bdev_excl);
+EXPORT_SYMBOL(open_bdev_exclusive);
 
 /**
- * close_bdev_excl  -  release a blockdevice openen by open_bdev_excl()
+ * close_bdev_exclusive  -  close a blockdevice opened by open_bdev_exclusive()
  *
  * @bdev:       blockdevice to close
+ * @mode:       mode, must match that used to open.
  *
- * This is the counterpart to open_bdev_excl().
+ * This is the counterpart to open_bdev_exclusive().
  */
-void close_bdev_excl(struct block_device *bdev)
+void close_bdev_exclusive(struct block_device *bdev, fmode_t mode)
 {
         bd_release(bdev);
-        blkdev_put(bdev, 0);    /* move up in the next patches */
+        blkdev_put(bdev, mode);
 }
 
-EXPORT_SYMBOL(close_bdev_excl);
+EXPORT_SYMBOL(close_bdev_exclusive);
 
 int __invalidate_device(struct block_device *bdev)
 {
diff --git a/fs/reiserfs/journal.c b/fs/reiserfs/journal.c
index 3261518478f4..70b896076676 100644
--- a/fs/reiserfs/journal.c
+++ b/fs/reiserfs/journal.c
@@ -2628,7 +2628,8 @@ static int journal_init_dev(struct super_block *super,
                 return 0;
         }
 
-        journal->j_dev_bd = open_bdev_excl(jdev_name, 0, journal);
+        journal->j_dev_bd = open_bdev_exclusive(jdev_name,
+                                                FMODE_READ|FMODE_WRITE, journal);
         if (IS_ERR(journal->j_dev_bd)) {
                 result = PTR_ERR(journal->j_dev_bd);
                 journal->j_dev_bd = NULL;
diff --git a/fs/super.c b/fs/super.c
index e931ae9511fe..0d77ac20d03e 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -760,9 +760,13 @@ int get_sb_bdev(struct file_system_type *fs_type,
 {
         struct block_device *bdev;
         struct super_block *s;
+        fmode_t mode = FMODE_READ;
         int error = 0;
 
-        bdev = open_bdev_excl(dev_name, flags, fs_type);
+        if (!(flags & MS_RDONLY))
+                mode |= FMODE_WRITE;
+
+        bdev = open_bdev_exclusive(dev_name, mode, fs_type);
         if (IS_ERR(bdev))
                 return PTR_ERR(bdev);
 
@@ -785,11 +789,12 @@ int get_sb_bdev(struct file_system_type *fs_type,
                         goto error_bdev;
                 }
 
-                close_bdev_excl(bdev);
+                close_bdev_exclusive(bdev, mode);
         } else {
                 char b[BDEVNAME_SIZE];
 
                 s->s_flags = flags;
+                s->s_mode = mode;
                 strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id));
                 sb_set_blocksize(s, block_size(bdev));
                 error = fill_super(s, data, flags & MS_SILENT ? 1 : 0);
@@ -807,7 +812,7 @@ int get_sb_bdev(struct file_system_type *fs_type,
 error_s:
         error = PTR_ERR(s);
 error_bdev:
-        close_bdev_excl(bdev);
+        close_bdev_exclusive(bdev, mode);
 error:
         return error;
 }
@@ -817,10 +822,11 @@ EXPORT_SYMBOL(get_sb_bdev);
 void kill_block_super(struct super_block *sb)
 {
         struct block_device *bdev = sb->s_bdev;
+        fmode_t mode = sb->s_mode;
 
         generic_shutdown_super(sb);
         sync_blockdev(bdev);
-        close_bdev_excl(bdev);
+        close_bdev_exclusive(bdev, mode);
 }
 
 EXPORT_SYMBOL(kill_block_super);
diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c
index e39013619b26..37ebe36056eb 100644
--- a/fs/xfs/linux-2.6/xfs_super.c
+++ b/fs/xfs/linux-2.6/xfs_super.c
@@ -589,7 +589,7 @@ xfs_blkdev_get(
 {
         int                     error = 0;
 
-        *bdevp = open_bdev_excl(name, 0, mp);
+        *bdevp = open_bdev_exclusive(name, FMODE_READ|FMODE_WRITE, mp);
         if (IS_ERR(*bdevp)) {
                 error = PTR_ERR(*bdevp);
                 printk("XFS: Invalid device [%s], error=%d\n", name, error);
@@ -603,7 +603,7 @@ xfs_blkdev_put(
         struct block_device     *bdev)
 {
         if (bdev)
-                close_bdev_excl(bdev);
+                close_bdev_exclusive(bdev, FMODE_READ|FMODE_WRITE);
 }
 
 /*
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 04c8dc41f454..c6766314dc5e 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1157,6 +1157,7 @@ struct super_block {
         char s_id[32];                          /* Informational name */
 
         void                    *s_fs_info;     /* Filesystem private info */
+        fmode_t                 s_mode;
 
         /*
          * The next field is for VFS *only*. No filesystems have any business
@@ -1753,9 +1754,10 @@ extern void chrdev_show(struct seq_file *,off_t);
 extern const char *__bdevname(dev_t, char *buffer);
 extern const char *bdevname(struct block_device *bdev, char *buffer);
 extern struct block_device *lookup_bdev(const char *);
-extern struct block_device *open_bdev_excl(const char *, int, void *);
-extern void close_bdev_excl(struct block_device *);
+extern struct block_device *open_bdev_exclusive(const char *, fmode_t, void *);
+extern void close_bdev_exclusive(struct block_device *, fmode_t);
 extern void blkdev_show(struct seq_file *,off_t);
+
 #else
 #define BLKDEV_MAJOR_HASH_SIZE  0
 #endif