Merge branch 'reiserfs/kill-bkl' of git://git.kernel.org/pub/scm/linu…

…x/kernel/git/frederic/random-tracing

* 'reiserfs/kill-bkl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing: (31 commits)
  kill-the-bkl/reiserfs: turn GFP_ATOMIC flag to GFP_NOFS in reiserfs_get_block()
  kill-the-bkl/reiserfs: drop the fs race watchdog from _get_block_create_0()
  kill-the-bkl/reiserfs: definitely drop the bkl from reiserfs_ioctl()
  kill-the-bkl/reiserfs: always lock the ioctl path
  kill-the-bkl/reiserfs: fix reiserfs lock to cpu_add_remove_lock dependency
  kill-the-bkl/reiserfs: Fix induced mm->mmap_sem to sysfs_mutex dependency
  kill-the-bkl/reiserfs: panic in case of lock imbalance
  kill-the-bkl/reiserfs: fix recursive reiserfs write lock in reiserfs_commit_write()
  kill-the-bkl/reiserfs: fix recursive reiserfs lock in reiserfs_mkdir()
  kill-the-bkl/reiserfs: fix "reiserfs lock" / "inode mutex" lock inversion dependency
  kill-the-bkl/reiserfs: move the concurrent tree accesses checks per superblock
  kill-the-bkl/reiserfs: acquire the inode mutex safely
  kill-the-bkl/reiserfs: unlock only when needed in search_by_key
  kill-the-bkl/reiserfs: use mutex_lock in reiserfs_mutex_lock_safe
  kill-the-bkl/reiserfs: factorize the locking in reiserfs_write_end()
  kill-the-bkl/reiserfs: reduce number of contentions in search_by_key()
  kill-the-bkl/reiserfs: don't hold the write recursively in reiserfs_lookup()
  kill-the-bkl/reiserfs: lock only once on reiserfs_get_block()
  kill-the-bkl/reiserfs: conditionaly release the write lock on fs_changed()
  kill-the-BKL/reiserfs: add reiserfs_cond_resched()
  ...

fs/reiserfs/Makefile

@@ -7,7 +7,7 @@ obj-$(CONFIG_REISERFS_FS) += reiserfs.o
 reiserfs-objs := bitmap.o do_balan.o namei.o inode.o file.o dir.o fix_node.o \
 		 super.o prints.o objectid.o lbalance.o ibalance.o stree.o \
 		 hashes.o tail_conversion.o journal.o resize.o \
-		 item_ops.o ioctl.o procfs.o xattr.o
+		 item_ops.o ioctl.o procfs.o xattr.o lock.o
 
 ifeq ($(CONFIG_REISERFS_FS_XATTR),y)
 reiserfs-objs += xattr_user.o xattr_trusted.o

fs/reiserfs/bitmap.c

@@ -1249,14 +1249,18 @@ struct buffer_head *reiserfs_read_bitmap_block(struct super_block *sb,
 	else if (bitmap == 0)
 		block = (REISERFS_DISK_OFFSET_IN_BYTES >> sb->s_blocksize_bits) + 1;
 
+	reiserfs_write_unlock(sb);
 	bh = sb_bread(sb, block);
+	reiserfs_write_lock(sb);
 	if (bh == NULL)
 		reiserfs_warning(sb, "sh-2029: %s: bitmap block (#%u) "
 		                 "reading failed", __func__, block);
 	else {
 		if (buffer_locked(bh)) {
 			PROC_INFO_INC(sb, scan_bitmap.wait);
+			reiserfs_write_unlock(sb);
 			__wait_on_buffer(bh);
+			reiserfs_write_lock(sb);
 		}
 		BUG_ON(!buffer_uptodate(bh));
 		BUG_ON(atomic_read(&bh->b_count) == 0);

fs/reiserfs/dir.c

@@ -20,7 +20,7 @@ const struct file_operations reiserfs_dir_operations = {
 	.read = generic_read_dir,
 	.readdir = reiserfs_readdir,
 	.fsync = reiserfs_dir_fsync,
-	.ioctl = reiserfs_ioctl,
+	.unlocked_ioctl = reiserfs_ioctl,
 #ifdef CONFIG_COMPAT
 	.compat_ioctl = reiserfs_compat_ioctl,
 #endif
@@ -174,14 +174,22 @@ int reiserfs_readdir_dentry(struct dentry *dentry, void *dirent,
 				// user space buffer is swapped out. At that time
 				// entry can move to somewhere else
 				memcpy(local_buf, d_name, d_reclen);
+
+				/*
+				 * Since filldir might sleep, we can release
+				 * the write lock here for other waiters
+				 */
+				reiserfs_write_unlock(inode->i_sb);
 				if (filldir
 				    (dirent, local_buf, d_reclen, d_off, d_ino,
 				     DT_UNKNOWN) < 0) {
+					reiserfs_write_lock(inode->i_sb);
 					if (local_buf != small_buf) {
 						kfree(local_buf);
 					}
 					goto end;
 				}
+				reiserfs_write_lock(inode->i_sb);
 				if (local_buf != small_buf) {
 					kfree(local_buf);
 				}

fs/reiserfs/do_balan.c

@@ -21,14 +21,6 @@
 #include <linux/buffer_head.h>
 #include <linux/kernel.h>
 
-#ifdef CONFIG_REISERFS_CHECK
-
-struct tree_balance *cur_tb = NULL;	/* detects whether more than one
-					   copy of tb exists as a means
-					   of checking whether schedule
-					   is interrupting do_balance */
-#endif
-
 static inline void buffer_info_init_left(struct tree_balance *tb,
                                          struct buffer_info *bi)
 {
@@ -1840,11 +1832,12 @@ static int check_before_balancing(struct tree_balance *tb)
 {
 	int retval = 0;
 
-	if (cur_tb) {
+	if (REISERFS_SB(tb->tb_sb)->cur_tb) {
 		reiserfs_panic(tb->tb_sb, "vs-12335", "suspect that schedule "
 			       "occurred based on cur_tb not being null at "
 			       "this point in code. do_balance cannot properly "
-			       "handle schedule occurring while it runs.");
+			       "handle concurrent tree accesses on a same "
+			       "mount point.");
 	}
 
 	/* double check that buffers that we will modify are unlocked. (fix_nodes should already have
@@ -1986,7 +1979,7 @@ static inline void do_balance_starts(struct tree_balance *tb)
 	     "check");*/
 	RFALSE(check_before_balancing(tb), "PAP-12340: locked buffers in TB");
 #ifdef CONFIG_REISERFS_CHECK
-	cur_tb = tb;
+	REISERFS_SB(tb->tb_sb)->cur_tb = tb;
 #endif
 }
 
@@ -1996,7 +1989,7 @@ static inline void do_balance_completed(struct tree_balance *tb)
 #ifdef CONFIG_REISERFS_CHECK
 	check_leaf_level(tb);
 	check_internal_levels(tb);
-	cur_tb = NULL;
+	REISERFS_SB(tb->tb_sb)->cur_tb = NULL;
 #endif
 
 	/* reiserfs_free_block is no longer schedule safe.  So, we need to

fs/reiserfs/file.c

@@ -284,7 +284,7 @@ static ssize_t reiserfs_file_write(struct file *file,	/* the file we are going t
 const struct file_operations reiserfs_file_operations = {
 	.read = do_sync_read,
 	.write = reiserfs_file_write,
-	.ioctl = reiserfs_ioctl,
+	.unlocked_ioctl = reiserfs_ioctl,
 #ifdef CONFIG_COMPAT
 	.compat_ioctl = reiserfs_compat_ioctl,
 #endif

fs/reiserfs/fix_node.c

@@ -563,9 +563,6 @@ static int get_num_ver(int mode, struct tree_balance *tb, int h,
 	return needed_nodes;
 }
 
-#ifdef CONFIG_REISERFS_CHECK
-extern struct tree_balance *cur_tb;
-#endif
 
 /* Set parameters for balancing.
  * Performs write of results of analysis of balancing into structure tb,
@@ -1022,7 +1019,11 @@ static int get_far_parent(struct tree_balance *tb,
 	/* Check whether the common parent is locked. */
 
 	if (buffer_locked(*pcom_father)) {
+
+		/* Release the write lock while the buffer is busy */
+		reiserfs_write_unlock(tb->tb_sb);
 		__wait_on_buffer(*pcom_father);
+		reiserfs_write_lock(tb->tb_sb);
 		if (FILESYSTEM_CHANGED_TB(tb)) {
 			brelse(*pcom_father);
 			return REPEAT_SEARCH;
@@ -1927,7 +1928,9 @@ static int get_direct_parent(struct tree_balance *tb, int h)
 		return REPEAT_SEARCH;
 
 	if (buffer_locked(bh)) {
+		reiserfs_write_unlock(tb->tb_sb);
 		__wait_on_buffer(bh);
+		reiserfs_write_lock(tb->tb_sb);
 		if (FILESYSTEM_CHANGED_TB(tb))
 			return REPEAT_SEARCH;
 	}
@@ -1965,7 +1968,9 @@ static int get_neighbors(struct tree_balance *tb, int h)
 		     tb->FL[h]) ? tb->lkey[h] : B_NR_ITEMS(tb->
 								       FL[h]);
 		son_number = B_N_CHILD_NUM(tb->FL[h], child_position);
+		reiserfs_write_unlock(sb);
 		bh = sb_bread(sb, son_number);
+		reiserfs_write_lock(sb);
 		if (!bh)
 			return IO_ERROR;
 		if (FILESYSTEM_CHANGED_TB(tb)) {
@@ -2003,7 +2008,9 @@ static int get_neighbors(struct tree_balance *tb, int h)
 		child_position =
 		    (bh == tb->FR[h]) ? tb->rkey[h] + 1 : 0;
 		son_number = B_N_CHILD_NUM(tb->FR[h], child_position);
+		reiserfs_write_unlock(sb);
 		bh = sb_bread(sb, son_number);
+		reiserfs_write_lock(sb);
 		if (!bh)
 			return IO_ERROR;
 		if (FILESYSTEM_CHANGED_TB(tb)) {
@@ -2278,7 +2285,9 @@ static int wait_tb_buffers_until_unlocked(struct tree_balance *tb)
 				    REPEAT_SEARCH : CARRY_ON;
 			}
 #endif
+			reiserfs_write_unlock(tb->tb_sb);
 			__wait_on_buffer(locked);
+			reiserfs_write_lock(tb->tb_sb);
 			if (FILESYSTEM_CHANGED_TB(tb))
 				return REPEAT_SEARCH;
 		}
@@ -2349,12 +2358,14 @@ int fix_nodes(int op_mode, struct tree_balance *tb,
 
 	/* if it possible in indirect_to_direct conversion */
 	if (buffer_locked(tbS0)) {
+		reiserfs_write_unlock(tb->tb_sb);
 		__wait_on_buffer(tbS0);
+		reiserfs_write_lock(tb->tb_sb);
 		if (FILESYSTEM_CHANGED_TB(tb))
 			return REPEAT_SEARCH;
 	}
 #ifdef CONFIG_REISERFS_CHECK
-	if (cur_tb) {
+	if (REISERFS_SB(tb->tb_sb)->cur_tb) {
 		print_cur_tb("fix_nodes");
 		reiserfs_panic(tb->tb_sb, "PAP-8305",
 			       "there is pending do_balance");