Fix reiserfs_file_release()
a) count file openers correctly; i_count use was completely wrong
b) use new mutex for exclusion between final close/open/truncate,
to protect tailpacking logics. i_mutex use was wrong and resulted
in deadlocks.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/reiserfs/file.c b/fs/reiserfs/file.c
index b82cdd8..6846371 100644
--- a/fs/reiserfs/file.c
+++ b/fs/reiserfs/file.c
@@ -38,19 +38,23 @@
BUG_ON(!S_ISREG(inode->i_mode));
- /* fast out for when nothing needs to be done */
- if ((atomic_read(&inode->i_count) > 1 ||
- !(REISERFS_I(inode)->i_flags & i_pack_on_close_mask) ||
- !tail_has_to_be_packed(inode)) &&
- REISERFS_I(inode)->i_prealloc_count <= 0) {
+ if (atomic_add_unless(&REISERFS_I(inode)->openers, -1, 1))
+ return 0;
+
+ mutex_lock(&(REISERFS_I(inode)->tailpack));
+
+ if (!atomic_dec_and_test(&REISERFS_I(inode)->openers)) {
+ mutex_unlock(&(REISERFS_I(inode)->tailpack));
return 0;
}
- mutex_lock(&inode->i_mutex);
-
- mutex_lock(&(REISERFS_I(inode)->i_mmap));
- if (REISERFS_I(inode)->i_flags & i_ever_mapped)
- REISERFS_I(inode)->i_flags &= ~i_pack_on_close_mask;
+ /* fast out for when nothing needs to be done */
+ if ((!(REISERFS_I(inode)->i_flags & i_pack_on_close_mask) ||
+ !tail_has_to_be_packed(inode)) &&
+ REISERFS_I(inode)->i_prealloc_count <= 0) {
+ mutex_unlock(&(REISERFS_I(inode)->tailpack));
+ return 0;
+ }
reiserfs_write_lock(inode->i_sb);
/* freeing preallocation only involves relogging blocks that
@@ -94,9 +98,10 @@
if (!err)
err = jbegin_failure;
- if (!err && atomic_read(&inode->i_count) <= 1 &&
+ if (!err &&
(REISERFS_I(inode)->i_flags & i_pack_on_close_mask) &&
tail_has_to_be_packed(inode)) {
+
/* if regular file is released by last holder and it has been
appended (we append by unformatted node only) or its direct
item(s) had to be converted, then it may have to be
@@ -104,27 +109,28 @@
err = reiserfs_truncate_file(inode, 0);
}
out:
- mutex_unlock(&(REISERFS_I(inode)->i_mmap));
- mutex_unlock(&inode->i_mutex);
reiserfs_write_unlock(inode->i_sb);
+ mutex_unlock(&(REISERFS_I(inode)->tailpack));
return err;
}
-static int reiserfs_file_mmap(struct file *file, struct vm_area_struct *vma)
+static int reiserfs_file_open(struct inode *inode, struct file *file)
{
- struct inode *inode;
-
- inode = file->f_path.dentry->d_inode;
- mutex_lock(&(REISERFS_I(inode)->i_mmap));
- REISERFS_I(inode)->i_flags |= i_ever_mapped;
- mutex_unlock(&(REISERFS_I(inode)->i_mmap));
-
- return generic_file_mmap(file, vma);
+ int err = dquot_file_open(inode, file);
+ if (!atomic_inc_not_zero(&REISERFS_I(inode)->openers)) {
+ /* somebody might be tailpacking on final close; wait for it */
+ mutex_lock(&(REISERFS_I(inode)->tailpack));
+ atomic_inc(&REISERFS_I(inode)->openers);
+ mutex_unlock(&(REISERFS_I(inode)->tailpack));
+ }
+ return err;
}
static void reiserfs_vfs_truncate_file(struct inode *inode)
{
+ mutex_lock(&(REISERFS_I(inode)->tailpack));
reiserfs_truncate_file(inode, 1);
+ mutex_unlock(&(REISERFS_I(inode)->tailpack));
}
/* Sync a reiserfs file. */
@@ -288,8 +294,8 @@
#ifdef CONFIG_COMPAT
.compat_ioctl = reiserfs_compat_ioctl,
#endif
- .mmap = reiserfs_file_mmap,
- .open = dquot_file_open,
+ .mmap = generic_file_mmap,
+ .open = reiserfs_file_open,
.release = reiserfs_file_release,
.fsync = reiserfs_sync_file,
.aio_read = generic_file_aio_read,