diff options
| -rw-r--r-- | fs/gfs2/super.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c index 3b227274279..43a24f2e590 100644 --- a/fs/gfs2/super.c +++ b/fs/gfs2/super.c @@ -180,6 +180,24 @@ static int end_bio_io_page(struct bio *bio, unsigned int bytes_done, int error) return 0; } +/** + * gfs2_read_super - Read the gfs2 super block from disk + * @sb: The VFS super block + * @sector: The location of the super block + * + * This uses the bio functions to read the super block from disk + * because we want to be 100% sure that we never read cached data. + * A super block is read twice only during each GFS2 mount and is + * never written to by the filesystem. The first time its read no + * locks are held, and the only details which are looked at are those + * relating to the locking protocol. Once locking is up and working, + * the sb is read again under the lock to establish the location of + * the master directory (contains pointers to journals etc) and the + * root directory. + * + * Returns: A page containing the sb or NULL + */ + struct page *gfs2_read_super(struct super_block *sb, sector_t sector) { struct page *page; |