Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

Pull btrfs changes from Chris Mason:
 "This is a pretty long stream of bug fixes and performance fixes.

  Qu Wenruo has replaced the btrfs async threads with regular kernel
  workqueues.  We'll keep an eye out for performance differences, but
  it's nice to be using more generic code for this.

  We still have some corruption fixes and other patches coming in for
  the merge window, but this batch is tested and ready to go"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (108 commits)
  Btrfs: fix a crash of clone with inline extents's split
  btrfs: fix uninit variable warning
  Btrfs: take into account total references when doing backref lookup
  Btrfs: part 2, fix incremental send's decision to delay a dir move/rename
  Btrfs: fix incremental send's decision to delay a dir move/rename
  Btrfs: remove unnecessary inode generation lookup in send
  Btrfs: fix race when updating existing ref head
  btrfs: Add trace for btrfs_workqueue alloc/destroy
  Btrfs: less fs tree lock contention when using autodefrag
  Btrfs: return EPERM when deleting a default subvolume
  Btrfs: add missing kfree in btrfs_destroy_workqueue
  Btrfs: cache extent states in defrag code path
  Btrfs: fix deadlock with nested trans handles
  Btrfs: fix possible empty list access when flushing the delalloc inodes
  Btrfs: split the global ordered extents mutex
  Btrfs: don't flush all delalloc inodes when we doesn't get s_umount lock
  Btrfs: reclaim delalloc metadata more aggressively
  Btrfs: remove unnecessary lock in may_commit_transaction()
  Btrfs: remove the unnecessary flush when preparing the pages
  Btrfs: just do dirty page flush for the inode with compression before direct IO
  ...

1 files changed, 162 insertions, 74 deletions

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 39d83da03e03..e2f45fc02610 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -136,13 +136,20 @@ static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
  * syncing the tree wait for us to finish
  */
 static int start_log_trans(struct btrfs_trans_handle *trans,
-			   struct btrfs_root *root)
+			   struct btrfs_root *root,
+			   struct btrfs_log_ctx *ctx)
 {
+	int index;
 	int ret;
-	int err = 0;
 
 	mutex_lock(&root->log_mutex);
 	if (root->log_root) {
+		if (ACCESS_ONCE(root->fs_info->last_trans_log_full_commit) ==
+		    trans->transid) {
+			ret = -EAGAIN;
+			goto out;
+		}
+
 		if (!root->log_start_pid) {
 			root->log_start_pid = current->pid;
 			root->log_multiple_pids = false;
@@ -152,27 +159,40 @@ static int start_log_trans(struct btrfs_trans_handle *trans,
 
 		atomic_inc(&root->log_batch);
 		atomic_inc(&root->log_writers);
+		if (ctx) {
+			index = root->log_transid % 2;
+			list_add_tail(&ctx->list, &root->log_ctxs[index]);
+			ctx->log_transid = root->log_transid;
+		}
 		mutex_unlock(&root->log_mutex);
 		return 0;
 	}
-	root->log_multiple_pids = false;
-	root->log_start_pid = current->pid;
+
+	ret = 0;
 	mutex_lock(&root->fs_info->tree_log_mutex);
-	if (!root->fs_info->log_root_tree) {
+	if (!root->fs_info->log_root_tree)
 		ret = btrfs_init_log_root_tree(trans, root->fs_info);
-		if (ret)
-			err = ret;
-	}
-	if (err == 0 && !root->log_root) {
+	mutex_unlock(&root->fs_info->tree_log_mutex);
+	if (ret)
+		goto out;
+
+	if (!root->log_root) {
 		ret = btrfs_add_log_tree(trans, root);
 		if (ret)
-			err = ret;
+			goto out;
 	}
-	mutex_unlock(&root->fs_info->tree_log_mutex);
+	root->log_multiple_pids = false;
+	root->log_start_pid = current->pid;
 	atomic_inc(&root->log_batch);
 	atomic_inc(&root->log_writers);
+	if (ctx) {
+		index = root->log_transid % 2;
+		list_add_tail(&ctx->list, &root->log_ctxs[index]);
+		ctx->log_transid = root->log_transid;
+	}
+out:
 	mutex_unlock(&root->log_mutex);
-	return err;
+	return ret;
 }
 
 /*
@@ -2359,8 +2379,8 @@ static int update_log_root(struct btrfs_trans_handle *trans,
 	return ret;
 }
 
-static int wait_log_commit(struct btrfs_trans_handle *trans,
-			   struct btrfs_root *root, unsigned long transid)
+static void wait_log_commit(struct btrfs_trans_handle *trans,
+			    struct btrfs_root *root, int transid)
 {
 	DEFINE_WAIT(wait);
 	int index = transid % 2;
@@ -2375,36 +2395,63 @@ static int wait_log_commit(struct btrfs_trans_handle *trans,
 				&wait, TASK_UNINTERRUPTIBLE);
 		mutex_unlock(&root->log_mutex);
 
-		if (root->fs_info->last_trans_log_full_commit !=
-		    trans->transid && root->log_transid < transid + 2 &&
+		if (root->log_transid_committed < transid &&
 		    atomic_read(&root->log_commit[index]))
 			schedule();
 
 		finish_wait(&root->log_commit_wait[index], &wait);
 		mutex_lock(&root->log_mutex);
-	} while (root->fs_info->last_trans_log_full_commit !=
-		 trans->transid && root->log_transid < transid + 2 &&
+	} while (root->log_transid_committed < transid &&
 		 atomic_read(&root->log_commit[index]));
-	return 0;
 }
 
 static void wait_for_writer(struct btrfs_trans_handle *trans,
 			    struct btrfs_root *root)
 {
 	DEFINE_WAIT(wait);
-	while (root->fs_info->last_trans_log_full_commit !=
-	       trans->transid && atomic_read(&root->log_writers)) {
+
+	while (atomic_read(&root->log_writers)) {
 		prepare_to_wait(&root->log_writer_wait,
 				&wait, TASK_UNINTERRUPTIBLE);
 		mutex_unlock(&root->log_mutex);
-		if (root->fs_info->last_trans_log_full_commit !=
-		    trans->transid && atomic_read(&root->log_writers))
+		if (atomic_read(&root->log_writers))
 			schedule();
 		mutex_lock(&root->log_mutex);
 		finish_wait(&root->log_writer_wait, &wait);
 	}
 }
 
+static inline void btrfs_remove_log_ctx(struct btrfs_root *root,
+					struct btrfs_log_ctx *ctx)
+{
+	if (!ctx)
+		return;
+
+	mutex_lock(&root->log_mutex);
+	list_del_init(&ctx->list);
+	mutex_unlock(&root->log_mutex);
+}
+
+/* 
+ * Invoked in log mutex context, or be sure there is no other task which
+ * can access the list.
+ */
+static inline void btrfs_remove_all_log_ctxs(struct btrfs_root *root,
+					     int index, int error)
+{
+	struct btrfs_log_ctx *ctx;
+
+	if (!error) {
+		INIT_LIST_HEAD(&root->log_ctxs[index]);
+		return;
+	}
+
+	list_for_each_entry(ctx, &root->log_ctxs[index], list)
+		ctx->log_ret = error;
+
+	INIT_LIST_HEAD(&root->log_ctxs[index]);
+}
+
 /*
  * btrfs_sync_log does sends a given tree log down to the disk and
  * updates the super blocks to record it.  When this call is done,
@@ -2418,7 +2465,7 @@ static void wait_for_writer(struct btrfs_trans_handle *trans,
  * that has happened.
  */
 int btrfs_sync_log(struct btrfs_trans_handle *trans,
-		   struct btrfs_root *root)
+		   struct btrfs_root *root, struct btrfs_log_ctx *ctx)
 {
 	int index1;
 	int index2;
@@ -2426,22 +2473,30 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	int ret;
 	struct btrfs_root *log = root->log_root;
 	struct btrfs_root *log_root_tree = root->fs_info->log_root_tree;
-	unsigned long log_transid = 0;
+	int log_transid = 0;
+	struct btrfs_log_ctx root_log_ctx;
 	struct blk_plug plug;
 
 	mutex_lock(&root->log_mutex);
-	log_transid = root->log_transid;
-	index1 = root->log_transid % 2;
+	log_transid = ctx->log_transid;
+	if (root->log_transid_committed >= log_transid) {
+		mutex_unlock(&root->log_mutex);
+		return ctx->log_ret;
+	}
+
+	index1 = log_transid % 2;
 	if (atomic_read(&root->log_commit[index1])) {
-		wait_log_commit(trans, root, root->log_transid);
+		wait_log_commit(trans, root, log_transid);
 		mutex_unlock(&root->log_mutex);
-		return 0;
+		return ctx->log_ret;
 	}
+	ASSERT(log_transid == root->log_transid);
 	atomic_set(&root->log_commit[index1], 1);
 
 	/* wait for previous tree log sync to complete */
 	if (atomic_read(&root->log_commit[(index1 + 1) % 2]))
-		wait_log_commit(trans, root, root->log_transid - 1);
+		wait_log_commit(trans, root, log_transid - 1);
+
 	while (1) {
 		int batch = atomic_read(&root->log_batch);
 		/* when we're on an ssd, just kick the log commit out */
@@ -2456,7 +2511,8 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	}
 
 	/* bail out if we need to do a full commit */
-	if (root->fs_info->last_trans_log_full_commit == trans->transid) {
+	if (ACCESS_ONCE(root->fs_info->last_trans_log_full_commit) ==
+	    trans->transid) {
 		ret = -EAGAIN;
 		btrfs_free_logged_extents(log, log_transid);
 		mutex_unlock(&root->log_mutex);
@@ -2477,6 +2533,8 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 		blk_finish_plug(&plug);
 		btrfs_abort_transaction(trans, root, ret);
 		btrfs_free_logged_extents(log, log_transid);
+		ACCESS_ONCE(root->fs_info->last_trans_log_full_commit) =
+								trans->transid;
 		mutex_unlock(&root->log_mutex);
 		goto out;
 	}
@@ -2486,7 +2544,6 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	root->log_transid++;
 	log->log_transid = root->log_transid;
 	root->log_start_pid = 0;
-	smp_mb();
 	/*
 	 * IO has been started, blocks of the log tree have WRITTEN flag set
 	 * in their headers. new modifications of the log will be written to
@@ -2494,9 +2551,16 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	 */
 	mutex_unlock(&root->log_mutex);
 
+	btrfs_init_log_ctx(&root_log_ctx);
+
 	mutex_lock(&log_root_tree->log_mutex);
 	atomic_inc(&log_root_tree->log_batch);
 	atomic_inc(&log_root_tree->log_writers);
+
+	index2 = log_root_tree->log_transid % 2;
+	list_add_tail(&root_log_ctx.list, &log_root_tree->log_ctxs[index2]);
+	root_log_ctx.log_transid = log_root_tree->log_transid;
+
 	mutex_unlock(&log_root_tree->log_mutex);
 
 	ret = update_log_root(trans, log);
@@ -2509,13 +2573,17 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	}
 
 	if (ret) {
+		if (!list_empty(&root_log_ctx.list))
+			list_del_init(&root_log_ctx.list);
+
 		blk_finish_plug(&plug);
+		ACCESS_ONCE(root->fs_info->last_trans_log_full_commit) =
+								trans->transid;
 		if (ret != -ENOSPC) {
 			btrfs_abort_transaction(trans, root, ret);
 			mutex_unlock(&log_root_tree->log_mutex);
 			goto out;
 		}
-		root->fs_info->last_trans_log_full_commit = trans->transid;
 		btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark);
 		btrfs_free_logged_extents(log, log_transid);
 		mutex_unlock(&log_root_tree->log_mutex);
@@ -2523,22 +2591,29 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 		goto out;
 	}
 
-	index2 = log_root_tree->log_transid % 2;
+	if (log_root_tree->log_transid_committed >= root_log_ctx.log_transid) {
+		mutex_unlock(&log_root_tree->log_mutex);
+		ret = root_log_ctx.log_ret;
+		goto out;
+	}
+
+	index2 = root_log_ctx.log_transid % 2;
 	if (atomic_read(&log_root_tree->log_commit[index2])) {
 		blk_finish_plug(&plug);
 		btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark);
 		wait_log_commit(trans, log_root_tree,
-				log_root_tree->log_transid);
+				root_log_ctx.log_transid);
 		btrfs_free_logged_extents(log, log_transid);
 		mutex_unlock(&log_root_tree->log_mutex);
-		ret = 0;
+		ret = root_log_ctx.log_ret;
 		goto out;
 	}
+	ASSERT(root_log_ctx.log_transid == log_root_tree->log_transid);
 	atomic_set(&log_root_tree->log_commit[index2], 1);
 
 	if (atomic_read(&log_root_tree->log_commit[(index2 + 1) % 2])) {
 		wait_log_commit(trans, log_root_tree,
-				log_root_tree->log_transid - 1);
+				root_log_ctx.log_transid - 1);
 	}
 
 	wait_for_writer(trans, log_root_tree);
@@ -2547,7 +2622,8 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	 * now that we've moved on to the tree of log tree roots,
 	 * check the full commit flag again
 	 */
-	if (root->fs_info->last_trans_log_full_commit == trans->transid) {
+	if (ACCESS_ONCE(root->fs_info->last_trans_log_full_commit) ==
+	    trans->transid) {
 		blk_finish_plug(&plug);
 		btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark);
 		btrfs_free_logged_extents(log, log_transid);
@@ -2561,6 +2637,8 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 					 EXTENT_DIRTY | EXTENT_NEW);
 	blk_finish_plug(&plug);
 	if (ret) {
+		ACCESS_ONCE(root->fs_info->last_trans_log_full_commit) =
+								trans->transid;
 		btrfs_abort_transaction(trans, root, ret);
 		btrfs_free_logged_extents(log, log_transid);
 		mutex_unlock(&log_root_tree->log_mutex);
@@ -2578,8 +2656,6 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 				btrfs_header_level(log_root_tree->node));
 
 	log_root_tree->log_transid++;
-	smp_mb();
-
 	mutex_unlock(&log_root_tree->log_mutex);
 
 	/*
@@ -2591,6 +2667,8 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	 */
 	ret = write_ctree_super(trans, root->fs_info->tree_root, 1);
 	if (ret) {
+		ACCESS_ONCE(root->fs_info->last_trans_log_full_commit) =
+								trans->transid;
 		btrfs_abort_transaction(trans, root, ret);
 		goto out_wake_log_root;
 	}
@@ -2601,13 +2679,28 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	mutex_unlock(&root->log_mutex);
 
 out_wake_log_root:
+	/*
+	 * We needn't get log_mutex here because we are sure all
+	 * the other tasks are blocked.
+	 */
+	btrfs_remove_all_log_ctxs(log_root_tree, index2, ret);
+
+	mutex_lock(&log_root_tree->log_mutex);
+	log_root_tree->log_transid_committed++;
 	atomic_set(&log_root_tree->log_commit[index2], 0);
-	smp_mb();
+	mutex_unlock(&log_root_tree->log_mutex);
+
 	if (waitqueue_active(&log_root_tree->log_commit_wait[index2]))
 		wake_up(&log_root_tree->log_commit_wait[index2]);
 out:
+	/* See above. */
+	btrfs_remove_all_log_ctxs(root, index1, ret);
+
+	mutex_lock(&root->log_mutex);
+	root->log_transid_committed++;
 	atomic_set(&root->log_commit[index1], 0);
-	smp_mb();
+	mutex_unlock(&root->log_mutex);
+
 	if (waitqueue_active(&root->log_commit_wait[index1]))
 		wake_up(&root->log_commit_wait[index1]);
 	return ret;
@@ -3479,7 +3572,8 @@ static int extent_cmp(void *priv, struct list_head *a, struct list_head *b)
 
 static int log_one_extent(struct btrfs_trans_handle *trans,
 			  struct inode *inode, struct btrfs_root *root,
-			  struct extent_map *em, struct btrfs_path *path)
+			  struct extent_map *em, struct btrfs_path *path,
+			  struct list_head *logged_list)
 {
 	struct btrfs_root *log = root->log_root;
 	struct btrfs_file_extent_item *fi;
@@ -3495,7 +3589,6 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 	u64 extent_offset = em->start - em->orig_start;
 	u64 block_len;
 	int ret;
-	int index = log->log_transid % 2;
 	bool skip_csum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
 	int extent_inserted = 0;
 
@@ -3579,17 +3672,12 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 	 * First check and see if our csums are on our outstanding ordered
 	 * extents.
 	 */
-again:
-	spin_lock_irq(&log->log_extents_lock[index]);
-	list_for_each_entry(ordered, &log->logged_list[index], log_list) {
+	list_for_each_entry(ordered, logged_list, log_list) {
 		struct btrfs_ordered_sum *sum;
 
 		if (!mod_len)
 			break;
 
-		if (ordered->inode != inode)
-			continue;
-
 		if (ordered->file_offset + ordered->len <= mod_start ||
 		    mod_start + mod_len <= ordered->file_offset)
 			continue;
@@ -3632,12 +3720,6 @@ again:
 		if (test_and_set_bit(BTRFS_ORDERED_LOGGED_CSUM,
 				     &ordered->flags))
 			continue;
-		atomic_inc(&ordered->refs);
-		spin_unlock_irq(&log->log_extents_lock[index]);
-		/*
-		 * we've dropped the lock, we must either break or
-		 * start over after this.
-		 */
 
 		if (ordered->csum_bytes_left) {
 			btrfs_start_ordered_extent(inode, ordered, 0);
@@ -3647,16 +3729,11 @@ again:
 
 		list_for_each_entry(sum, &ordered->list, list) {
 			ret = btrfs_csum_file_blocks(trans, log, sum);
-			if (ret) {
-				btrfs_put_ordered_extent(ordered);
+			if (ret)
 				goto unlocked;
-			}
 		}
-		btrfs_put_ordered_extent(ordered);
-		goto again;
 
 	}
-	spin_unlock_irq(&log->log_extents_lock[index]);
 unlocked:
 
 	if (!mod_len || ret)
@@ -3694,7 +3771,8 @@ unlocked:
 static int btrfs_log_changed_extents(struct btrfs_trans_handle *trans,
 				     struct btrfs_root *root,
 				     struct inode *inode,
-				     struct btrfs_path *path)
+				     struct btrfs_path *path,
+				     struct list_head *logged_list)
 {
 	struct extent_map *em, *n;
 	struct list_head extents;
@@ -3752,7 +3830,7 @@ process:
 
 		write_unlock(&tree->lock);
 
-		ret = log_one_extent(trans, inode, root, em, path);
+		ret = log_one_extent(trans, inode, root, em, path, logged_list);
 		write_lock(&tree->lock);
 		clear_em_logging(tree, em);
 		free_extent_map(em);
@@ -3788,6 +3866,7 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
 	struct btrfs_key max_key;
 	struct btrfs_root *log = root->log_root;
 	struct extent_buffer *src = NULL;
+	LIST_HEAD(logged_list);
 	u64 last_extent = 0;
 	int err = 0;
 	int ret;
@@ -3836,7 +3915,7 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
 
 	mutex_lock(&BTRFS_I(inode)->log_mutex);
 
-	btrfs_get_logged_extents(log, inode);
+	btrfs_get_logged_extents(inode, &logged_list);
 
 	/*
 	 * a brute force approach to making sure we get the most uptodate
@@ -3962,7 +4041,8 @@ log_extents:
 	btrfs_release_path(path);
 	btrfs_release_path(dst_path);
 	if (fast_search) {
-		ret = btrfs_log_changed_extents(trans, root, inode, dst_path);
+		ret = btrfs_log_changed_extents(trans, root, inode, dst_path,
+						&logged_list);
 		if (ret) {
 			err = ret;
 			goto out_unlock;
@@ -3987,8 +4067,10 @@ log_extents:
 	BTRFS_I(inode)->logged_trans = trans->transid;
 	BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->last_sub_trans;
 out_unlock:
-	if (err)
-		btrfs_free_logged_extents(log, log->log_transid);
+	if (unlikely(err))
+		btrfs_put_logged_extents(&logged_list);
+	else
+		btrfs_submit_logged_extents(&logged_list, log);
 	mutex_unlock(&BTRFS_I(inode)->log_mutex);
 
 	btrfs_free_path(path);
@@ -4079,7 +4161,8 @@ out:
  */
 static int btrfs_log_inode_parent(struct btrfs_trans_handle *trans,
 			    	  struct btrfs_root *root, struct inode *inode,
-			    	  struct dentry *parent, int exists_only)
+			    	  struct dentry *parent, int exists_only,
+				  struct btrfs_log_ctx *ctx)
 {
 	int inode_only = exists_only ? LOG_INODE_EXISTS : LOG_INODE_ALL;
 	struct super_block *sb;
@@ -4116,9 +4199,9 @@ static int btrfs_log_inode_parent(struct btrfs_trans_handle *trans,
 		goto end_no_trans;
 	}
 
-	ret = start_log_trans(trans, root);
+	ret = start_log_trans(trans, root, ctx);
 	if (ret)
-		goto end_trans;
+		goto end_no_trans;
 
 	ret = btrfs_log_inode(trans, root, inode, inode_only);
 	if (ret)
@@ -4166,6 +4249,9 @@ end_trans:
 		root->fs_info->last_trans_log_full_commit = trans->transid;
 		ret = 1;
 	}
+
+	if (ret)
+		btrfs_remove_log_ctx(root, ctx);
 	btrfs_end_log_trans(root);
 end_no_trans:
 	return ret;
@@ -4178,12 +4264,14 @@ end_no_trans:
  * data on disk.
  */
 int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans,
-			  struct btrfs_root *root, struct dentry *dentry)
+			  struct btrfs_root *root, struct dentry *dentry,
+			  struct btrfs_log_ctx *ctx)
 {
 	struct dentry *parent = dget_parent(dentry);
 	int ret;
 
-	ret = btrfs_log_inode_parent(trans, root, dentry->d_inode, parent, 0);
+	ret = btrfs_log_inode_parent(trans, root, dentry->d_inode, parent,
+				     0, ctx);
 	dput(parent);
 
 	return ret;
@@ -4420,6 +4508,6 @@ int btrfs_log_new_name(struct btrfs_trans_handle *trans,
 		    root->fs_info->last_trans_committed))
 		return 0;
 
-	return btrfs_log_inode_parent(trans, root, inode, parent, 1);
+	return btrfs_log_inode_parent(trans, root, inode, parent, 1, NULL);
 }