[PATCH] Locking problems while EXT3FS_DEBUG on

I noticed some problems while running ext3 with the debug flag set on.
More precisely, I was unable to umount the filesystem.  Some investigation
took me to the patch that follows.

At a first glance , the lock/unlock I've taken out seems really not
necessary, as the main code (outside debug) does not lock the super.  The
only additional danger operations that debug code introduces seems to be
related to bitmap, but bitmap operations tends to be all atomic anyway.

I also took the opportunity to fix 2 spelling errors.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/ext3/balloc.c b/fs/ext3/balloc.c
index 0213db4911a2adfcd19bb92d33dfc5b0936a192b..032c7ba1b13f29d7340dadafd73b9abf635c0fbb 100644 (file)
--- a/fs/ext3/balloc.c
+++ b/fs/ext3/balloc.c
@@ -1010,7 +1010,7 @@ retry:
  * allocation within the reservation window.
  *
  * This will avoid keeping on searching the reservation list again and
- * again when someboday is looking for a free block (without
+ * again when somebody is looking for a free block (without
  * reservation), and there are lots of free blocks, but they are all
  * being reserved.
  *
@@ -1416,12 +1416,12 @@ unsigned long ext3_count_free_blocks(struct super_block *sb)
        unsigned long bitmap_count, x;
        struct buffer_head *bitmap_bh = NULL;
 
-       lock_super(sb);
        es = EXT3_SB(sb)->s_es;
        desc_count = 0;
        bitmap_count = 0;
        gdp = NULL;
 
+       smp_rmb();
        for (i = 0; i < ngroups; i++) {
                gdp = ext3_get_group_desc(sb, i, NULL);
                if (!gdp)
@@ -1440,7 +1440,6 @@ unsigned long ext3_count_free_blocks(struct super_block *sb)
        brelse(bitmap_bh);
        printk("ext3_count_free_blocks: stored = %u, computed = %lu, %lu\n",
               le32_to_cpu(es->s_free_blocks_count), desc_count, bitmap_count);
-       unlock_super(sb);
        return bitmap_count;
 #else
        desc_count = 0;

diff --git a/fs/ext3/ialloc.c b/fs/ext3/ialloc.c
index 6549945f9ac156ae0523108ffc3b8bfc0cd88448..0eb4f90268da502cc3edf706ad21d07a2c32eb32 100644 (file)
--- a/fs/ext3/ialloc.c
+++ b/fs/ext3/ialloc.c
@@ -704,7 +704,6 @@ unsigned long ext3_count_free_inodes (struct super_block * sb)
        unsigned long bitmap_count, x;
        struct buffer_head *bitmap_bh = NULL;
 
-       lock_super (sb);
        es = EXT3_SB(sb)->s_es;
        desc_count = 0;
        bitmap_count = 0;
@@ -727,7 +726,6 @@ unsigned long ext3_count_free_inodes (struct super_block * sb)
        brelse(bitmap_bh);
        printk("ext3_count_free_inodes: stored = %u, computed = %lu, %lu\n",
                le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
-       unlock_super(sb);
        return desc_count;
 #else
        desc_count = 0;

diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index 8b38f2232796fda9c0f25294654c49a8d25cde11..b5da5244e1444c28cf02b07819b38be5eebbaaaa 100644 (file)
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -491,7 +491,7 @@ static unsigned long ext3_find_goal(struct inode *inode, long block,
  *     the same format as ext3_get_branch() would do. We are calling it after
  *     we had read the existing part of chain and partial points to the last
  *     triple of that (one with zero ->key). Upon the exit we have the same
- *     picture as after the successful ext3_get_block(), excpet that in one
+ *     picture as after the successful ext3_get_block(), except that in one
  *     place chain is disconnected - *branch->p is still zero (we did not
  *     set the last link), but branch->key contains the number that should
  *     be placed into *branch->p to fill that gap.