bfs: extra sanity checking and static inode bitmap

[zynq/linux.git] / fs / bfs / bfs.h

diff --git a/fs/bfs/bfs.h b/fs/bfs/bfs.h
index 67aef3bb89e4c491b84691089020ecb15b00fdbf..606f9378b2f03d17c3f5abefd36ecb96c57c0773 100644 (file)
--- a/fs/bfs/bfs.h
+++ b/fs/bfs/bfs.h
@@ -1,13 +1,20 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 /*
  *     fs/bfs/bfs.h
- *     Copyright (C) 1999 Tigran Aivazian <tigran@veritas.com>
+ *     Copyright (C) 1999-2018 Tigran Aivazian <aivazian.tigran@gmail.com>
  */
 #ifndef _FS_BFS_BFS_H
 #define _FS_BFS_BFS_H
 
 #include <linux/bfs_fs.h>
 
+/* In theory BFS supports up to 512 inodes, numbered from 2 (for /) up to 513 inclusive.
+   In actual fact, attempting to create the 512th inode (i.e. inode No. 513 or file No. 511)
+   will fail with ENOSPC in bfs_add_entry(): the root directory cannot contain so many entries, counting '..'.
+   So, mkfs.bfs(8) should really limit its -N option to 511 and not 512. For now, we just print a warning
+   if a filesystem is mounted with such "impossible to fill up" number of inodes */
+#define BFS_MAX_LASTI  513
+
 /*
  * BFS file system in-core superblock info
  */
@@ -17,7 +24,7 @@ struct bfs_sb_info {
        unsigned long si_freei;
        unsigned long si_lf_eblk;
        unsigned long si_lasti;
-       unsigned long *si_imap;
+       DECLARE_BITMAP(si_imap, BFS_MAX_LASTI+1);
        struct mutex bfs_lock;
 };