hfsplus: add missing extent locking in hfsplus_write_inode
Most of the extent handling code already does proper SMP locking, but
hfsplus_write_inode was calling into hfsplus_ext_write_extent without
taking the extents_lock. Fix this by splitting hfsplus_ext_write_extent
into an internal helper that expects the lock, and a public interface
that first acquires it.
Also add a few locking asserts and document the locking rules in
hfsplus_fs.h.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
diff --git a/fs/hfsplus/hfsplus_fs.h b/fs/hfsplus/hfsplus_fs.h
index c521d44..c007cc2 100644
--- a/fs/hfsplus/hfsplus_fs.h
+++ b/fs/hfsplus/hfsplus_fs.h
@@ -158,28 +158,36 @@
struct hfsplus_inode_info {
- struct mutex extents_lock;
- u32 clump_blocks, alloc_blocks;
- sector_t fs_blocks;
- /* Allocation extents from catalog record or volume header */
- hfsplus_extent_rec first_extents;
- u32 first_blocks;
- hfsplus_extent_rec cached_extents;
- u32 cached_start, cached_blocks;
atomic_t opencnt;
- struct inode *rsrc_inode;
+ /*
+ * Extent allocation information, protected by extents_lock.
+ */
+ u32 first_blocks;
+ u32 clump_blocks;
+ u32 alloc_blocks;
+ u32 cached_start;
+ u32 cached_blocks;
+ hfsplus_extent_rec first_extents;
+ hfsplus_extent_rec cached_extents;
unsigned long flags;
+ struct mutex extents_lock;
+ /*
+ * Immutable data.
+ */
+ struct inode *rsrc_inode;
__be32 create_date;
- /* Device number in hfsplus_permissions in catalog */
u32 dev;
- /* BSD system and user file flags */
- u8 rootflags;
- u8 userflags;
+ /*
+ * Protected by i_mutex.
+ */
+ sector_t fs_blocks;
+ u8 rootflags, userflags; /* BSD system and user file flags */
struct list_head open_dir_list;
loff_t phys_size;
+
struct inode vfs_inode;
};