Merge branch 'reiserfs/kill-bkl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing

* 'reiserfs/kill-bkl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing:
  reiserfs: Safely acquire i_mutex from xattr_rmdir
  reiserfs: Safely acquire i_mutex from reiserfs_for_each_xattr
  reiserfs: Fix journal mutex <-> inode mutex lock inversion
  reiserfs: Fix unwanted recursive reiserfs lock in reiserfs_unlink()
  reiserfs: Relax lock before open xattr dir in reiserfs_xattr_set_handle()
  reiserfs: Relax reiserfs lock while freeing the journal
  reiserfs: Fix reiserfs lock <-> i_mutex dependency inversion on xattr
  reiserfs: Warn on lock relax if taken recursively
  reiserfs: Fix reiserfs lock <-> i_xattr_sem dependency inversion
  reiserfs: Fix remaining in-reclaim-fs <-> reclaim-fs-on locking inversion
  reiserfs: Fix reiserfs lock <-> inode mutex dependency inversion
  reiserfs: Fix reiserfs lock and journal lock inversion dependency
  reiserfs: Fix possible recursive lock

7 files changed, 79 insertions, 15 deletions

diff --git a/fs/reiserfs/bitmap.c b/fs/reiserfs/bitmap.c
index 685495707181..65c872761177 100644
--- a/fs/reiserfs/bitmap.c
+++ b/fs/reiserfs/bitmap.c
@@ -1277,7 +1277,10 @@ int reiserfs_init_bitmap_cache(struct super_block *sb)
 	struct reiserfs_bitmap_info *bitmap;
 	unsigned int bmap_nr = reiserfs_bmap_count(sb);
 
+	/* Avoid lock recursion in fault case */
+	reiserfs_write_unlock(sb);
 	bitmap = vmalloc(sizeof(*bitmap) * bmap_nr);
+	reiserfs_write_lock(sb);
 	if (bitmap == NULL)
 		return -ENOMEM;
 
diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c
index 290ae38fca8a..1150ebb2536f 100644
--- a/fs/reiserfs/inode.c
+++ b/fs/reiserfs/inode.c
@@ -31,11 +31,12 @@ void reiserfs_delete_inode(struct inode *inode)
 	    JOURNAL_PER_BALANCE_CNT * 2 +
 	    2 * REISERFS_QUOTA_INIT_BLOCKS(inode->i_sb);
 	struct reiserfs_transaction_handle th;
+	int depth;
 	int err;
 
 	truncate_inode_pages(&inode->i_data, 0);
 
-	reiserfs_write_lock(inode->i_sb);
+	depth = reiserfs_write_lock_once(inode->i_sb);
 
 	/* The = 0 happens when we abort creating a new inode for some reason like lack of space.. */
 	if (!(inode->i_state & I_NEW) && INODE_PKEY(inode)->k_objectid != 0) {	/* also handles bad_inode case */
@@ -74,7 +75,7 @@ void reiserfs_delete_inode(struct inode *inode)
       out:
 	clear_inode(inode);	/* note this must go after the journal_end to prevent deadlock */
 	inode->i_blocks = 0;
-	reiserfs_write_unlock(inode->i_sb);
+	reiserfs_write_unlock_once(inode->i_sb, depth);
 }
 
 static void _make_cpu_key(struct cpu_key *key, int version, __u32 dirid,
diff --git a/fs/reiserfs/journal.c b/fs/reiserfs/journal.c
index 2f8a7e7b8dab..83ac4d3b3cb0 100644
--- a/fs/reiserfs/journal.c
+++ b/fs/reiserfs/journal.c
@@ -2009,10 +2009,11 @@ static int do_journal_release(struct reiserfs_transaction_handle *th,
 		destroy_workqueue(commit_wq);
 		commit_wq = NULL;
 	}
-	reiserfs_write_lock(sb);
 
 	free_journal_ram(sb);
 
+	reiserfs_write_lock(sb);
+
 	return 0;
 }
 
@@ -2758,11 +2759,18 @@ int journal_init(struct super_block *sb, const char *j_dev_name,
 	struct reiserfs_journal *journal;
 	struct reiserfs_journal_list *jl;
 	char b[BDEVNAME_SIZE];
+	int ret;
 
+	/*
+	 * Unlock here to avoid various RECLAIM-FS-ON <-> IN-RECLAIM-FS
+	 * dependency inversion warnings.
+	 */
+	reiserfs_write_unlock(sb);
 	journal = SB_JOURNAL(sb) = vmalloc(sizeof(struct reiserfs_journal));
 	if (!journal) {
 		reiserfs_warning(sb, "journal-1256",
 				 "unable to get memory for journal structure");
+		reiserfs_write_lock(sb);
 		return 1;
 	}
 	memset(journal, 0, sizeof(struct reiserfs_journal));
@@ -2771,10 +2779,12 @@ int journal_init(struct super_block *sb, const char *j_dev_name,
 	INIT_LIST_HEAD(&journal->j_working_list);
 	INIT_LIST_HEAD(&journal->j_journal_list);
 	journal->j_persistent_trans = 0;
-	if (reiserfs_allocate_list_bitmaps(sb,
-					   journal->j_list_bitmap,
-					   reiserfs_bmap_count(sb)))
+	ret = reiserfs_allocate_list_bitmaps(sb, journal->j_list_bitmap,
+					   reiserfs_bmap_count(sb));
+	reiserfs_write_lock(sb);
+	if (ret)
 		goto free_and_return;
+
 	allocate_bitmap_nodes(sb);
 
 	/* reserved for journal area support */
diff --git a/fs/reiserfs/lock.c b/fs/reiserfs/lock.c
index ee2cfc0fd8a7..b87aa2c1afc1 100644
--- a/fs/reiserfs/lock.c
+++ b/fs/reiserfs/lock.c
@@ -86,3 +86,12 @@ void reiserfs_check_lock_depth(struct super_block *sb, char *caller)
 		reiserfs_panic(sb, "%s called without kernel lock held %d",
 			       caller);
 }
+
+#ifdef CONFIG_REISERFS_CHECK
+void reiserfs_lock_check_recursive(struct super_block *sb)
+{
+	struct reiserfs_sb_info *sb_i = REISERFS_SB(sb);
+
+	WARN_ONCE((sb_i->lock_depth > 0), "Unwanted recursive reiserfs lock!\n");
+}
+#endif
diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c
index e296ff72a6cc..9d4dcf0b07cb 100644
--- a/fs/reiserfs/namei.c
+++ b/fs/reiserfs/namei.c
@@ -921,6 +921,7 @@ static int reiserfs_unlink(struct inode *dir, struct dentry *dentry)
 	struct reiserfs_transaction_handle th;
 	int jbegin_count;
 	unsigned long savelink;
+	int depth;
 
 	inode = dentry->d_inode;
 
@@ -932,7 +933,7 @@ static int reiserfs_unlink(struct inode *dir, struct dentry *dentry)
 	    JOURNAL_PER_BALANCE_CNT * 2 + 2 +
 	    4 * REISERFS_QUOTA_TRANS_BLOCKS(dir->i_sb);
 
-	reiserfs_write_lock(dir->i_sb);
+	depth = reiserfs_write_lock_once(dir->i_sb);
 	retval = journal_begin(&th, dir->i_sb, jbegin_count);
 	if (retval)
 		goto out_unlink;
@@ -993,7 +994,7 @@ static int reiserfs_unlink(struct inode *dir, struct dentry *dentry)
 
 	retval = journal_end(&th, dir->i_sb, jbegin_count);
 	reiserfs_check_path(&path);
-	reiserfs_write_unlock(dir->i_sb);
+	reiserfs_write_unlock_once(dir->i_sb, depth);
 	return retval;
 
       end_unlink:
@@ -1003,7 +1004,7 @@ static int reiserfs_unlink(struct inode *dir, struct dentry *dentry)
 	if (err)
 		retval = err;
       out_unlink:
-	reiserfs_write_unlock(dir->i_sb);
+	reiserfs_write_unlock_once(dir->i_sb, depth);
 	return retval;
 }
 
diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c
index 8c7033a8b67e..c3b004ee627b 100644
--- a/fs/reiserfs/xattr.c
+++ b/fs/reiserfs/xattr.c
@@ -83,7 +83,8 @@ static int xattr_unlink(struct inode *dir, struct dentry *dentry)
 	BUG_ON(!mutex_is_locked(&dir->i_mutex));
 	vfs_dq_init(dir);
 
-	mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
+	reiserfs_mutex_lock_nested_safe(&dentry->d_inode->i_mutex,
+					I_MUTEX_CHILD, dir->i_sb);
 	error = dir->i_op->unlink(dir, dentry);
 	mutex_unlock(&dentry->d_inode->i_mutex);
 
@@ -98,7 +99,8 @@ static int xattr_rmdir(struct inode *dir, struct dentry *dentry)
 	BUG_ON(!mutex_is_locked(&dir->i_mutex));
 	vfs_dq_init(dir);
 
-	mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
+	reiserfs_mutex_lock_nested_safe(&dentry->d_inode->i_mutex,
+					I_MUTEX_CHILD, dir->i_sb);
 	dentry_unhash(dentry);
 	error = dir->i_op->rmdir(dir, dentry);
 	if (!error)
@@ -235,16 +237,22 @@ static int reiserfs_for_each_xattr(struct inode *inode,
 	if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1)
 		return 0;
 
+	reiserfs_write_unlock(inode->i_sb);
 	dir = open_xa_dir(inode, XATTR_REPLACE);
 	if (IS_ERR(dir)) {
 		err = PTR_ERR(dir);
+		reiserfs_write_lock(inode->i_sb);
 		goto out;
 	} else if (!dir->d_inode) {
 		err = 0;
+		reiserfs_write_lock(inode->i_sb);
 		goto out_dir;
 	}
 
 	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
+
+	reiserfs_write_lock(inode->i_sb);
+
 	buf.xadir = dir;
 	err = reiserfs_readdir_dentry(dir, &buf, fill_with_dentries, &pos);
 	while ((err == 0 || err == -ENOSPC) && buf.count) {
@@ -283,8 +291,9 @@ static int reiserfs_for_each_xattr(struct inode *inode,
 		err = journal_begin(&th, inode->i_sb, blocks);
 		if (!err) {
 			int jerror;
-			mutex_lock_nested(&dir->d_parent->d_inode->i_mutex,
-					  I_MUTEX_XATTR);
+			reiserfs_mutex_lock_nested_safe(
+					  &dir->d_parent->d_inode->i_mutex,
+					  I_MUTEX_XATTR, inode->i_sb);
 			err = action(dir, data);
 			jerror = journal_end(&th, inode->i_sb, blocks);
 			mutex_unlock(&dir->d_parent->d_inode->i_mutex);
@@ -480,11 +489,16 @@ reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
 	if (!buffer)
 		return lookup_and_delete_xattr(inode, name);
 
+	reiserfs_write_unlock(inode->i_sb);
 	dentry = xattr_lookup(inode, name, flags);
-	if (IS_ERR(dentry))
+	if (IS_ERR(dentry)) {
+		reiserfs_write_lock(inode->i_sb);
 		return PTR_ERR(dentry);
+	}
 
-	down_write(&REISERFS_I(inode)->i_xattr_sem);
+	down_read(&REISERFS_I(inode)->i_xattr_sem);
+
+	reiserfs_write_lock(inode->i_sb);
 
 	xahash = xattr_hash(buffer, buffer_size);
 	while (buffer_pos < buffer_size || buffer_pos == 0) {
diff --git a/include/linux/reiserfs_fs.h b/include/linux/reiserfs_fs.h
index c96c1858fe2c..1ba3cf6edfbb 100644
--- a/include/linux/reiserfs_fs.h
+++ b/include/linux/reiserfs_fs.h
@@ -62,6 +62,12 @@ void reiserfs_write_unlock(struct super_block *s);
 int reiserfs_write_lock_once(struct super_block *s);
 void reiserfs_write_unlock_once(struct super_block *s, int lock_depth);
 
+#ifdef CONFIG_REISERFS_CHECK
+void reiserfs_lock_check_recursive(struct super_block *s);
+#else
+static inline void reiserfs_lock_check_recursive(struct super_block *s) { }
+#endif
+
 /*
  * Several mutexes depend on the write lock.
  * However sometimes we want to relax the write lock while we hold
@@ -92,11 +98,31 @@ void reiserfs_write_unlock_once(struct super_block *s, int lock_depth);
 static inline void reiserfs_mutex_lock_safe(struct mutex *m,
 			       struct super_block *s)
 {
+	reiserfs_lock_check_recursive(s);
 	reiserfs_write_unlock(s);
 	mutex_lock(m);
 	reiserfs_write_lock(s);
 }
 
+static inline void
+reiserfs_mutex_lock_nested_safe(struct mutex *m, unsigned int subclass,
+			       struct super_block *s)
+{
+	reiserfs_lock_check_recursive(s);
+	reiserfs_write_unlock(s);
+	mutex_lock_nested(m, subclass);
+	reiserfs_write_lock(s);
+}
+
+static inline void
+reiserfs_down_read_safe(struct rw_semaphore *sem, struct super_block *s)
+{
+	reiserfs_lock_check_recursive(s);
+	reiserfs_write_unlock(s);
+	down_read(sem);
+	reiserfs_write_lock(s);
+}
+
 /*
  * When we schedule, we usually want to also release the write lock,
  * according to the previous bkl based locking scheme of reiserfs.