fat (exportfs): fix dentry reconnection
Maintain an index of directory inodes by starting cluster, so that
fat_get_parent() can return the proper cached inode rather than inventing
one that cannot be traced back to the filesystem root.
Add a new msdos/vfat binary mount option "nfs" so that FAT filesystems
that are _not_ exported via NFS are not saddled with maintenance of an
index they will never use.
Finally, simplify NFS file handle generation and lookups. An
ext2-congruent implementation is adequate for FAT needs.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index d70d8f3..55e088c 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -872,21 +872,23 @@
}
/*
- * The ".." entry can not provide the "struct fat_slot_info" informations
- * for inode. So, this function provide the some informations only.
+ * The ".." entry can not provide the "struct fat_slot_info" information
+ * for inode, nor a usable i_pos. So, this function provides some information
+ * only.
+ *
+ * Since this function walks through the on-disk inodes within a directory,
+ * callers are responsible for taking any locks necessary to prevent the
+ * directory from changing.
*/
int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
- struct msdos_dir_entry **de, loff_t *i_pos)
+ struct msdos_dir_entry **de)
{
- loff_t offset;
+ loff_t offset = 0;
- offset = 0;
- *bh = NULL;
+ *de = NULL;
while (fat_get_short_entry(dir, &offset, bh, de) >= 0) {
- if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME)) {
- *i_pos = fat_make_i_pos(dir->i_sb, *bh, *de);
+ if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME))
return 0;
- }
}
return -ENOENT;
}