1 files changed, 182 insertions, 154 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index a70c5790f8f5..247830107686 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -66,6 +66,13 @@ struct btrfs_iget_args {
 	struct btrfs_root *root;
 };
 
+struct btrfs_dio_data {
+	u64 outstanding_extents;
+	u64 reserve;
+	u64 unsubmitted_oe_range_start;
+	u64 unsubmitted_oe_range_end;
+};
+
 static const struct inode_operations btrfs_dir_inode_operations;
 static const struct inode_operations btrfs_symlink_inode_operations;
 static const struct inode_operations btrfs_dir_ro_inode_operations;
@@ -74,17 +81,16 @@ static const struct inode_operations btrfs_file_inode_operations;
 static const struct address_space_operations btrfs_aops;
 static const struct address_space_operations btrfs_symlink_aops;
 static const struct file_operations btrfs_dir_file_operations;
-static struct extent_io_ops btrfs_extent_io_ops;
+static const struct extent_io_ops btrfs_extent_io_ops;
 
 static struct kmem_cache *btrfs_inode_cachep;
-static struct kmem_cache *btrfs_delalloc_work_cachep;
 struct kmem_cache *btrfs_trans_handle_cachep;
 struct kmem_cache *btrfs_transaction_cachep;
 struct kmem_cache *btrfs_path_cachep;
 struct kmem_cache *btrfs_free_space_cachep;
 
 #define S_SHIFT 12
-static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
+static const unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
 	[S_IFREG >> S_SHIFT]	= BTRFS_FT_REG_FILE,
 	[S_IFDIR >> S_SHIFT]	= BTRFS_FT_DIR,
 	[S_IFCHR >> S_SHIFT]	= BTRFS_FT_CHRDEV,
@@ -414,15 +420,15 @@ static noinline void compress_file_range(struct inode *inode,
 	unsigned long nr_pages_ret = 0;
 	unsigned long total_compressed = 0;
 	unsigned long total_in = 0;
-	unsigned long max_compressed = 128 * 1024;
-	unsigned long max_uncompressed = 128 * 1024;
+	unsigned long max_compressed = SZ_128K;
+	unsigned long max_uncompressed = SZ_128K;
 	int i;
 	int will_compress;
 	int compress_type = root->fs_info->compress_type;
 	int redirty = 0;
 
 	/* if this is a small write inside eof, kick off a defrag */
-	if ((end - start + 1) < 16 * 1024 &&
+	if ((end - start + 1) < SZ_16K &&
 	    (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
 		btrfs_add_inode_defrag(NULL, inode);
 
@@ -430,7 +436,7 @@ static noinline void compress_file_range(struct inode *inode,
 again:
 	will_compress = 0;
 	nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
-	nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
+	nr_pages = min_t(unsigned long, nr_pages, SZ_128K / PAGE_CACHE_SIZE);
 
 	/*
 	 * we don't want to send crud past the end of i_size through
@@ -944,7 +950,7 @@ static noinline int cow_file_range(struct inode *inode,
 	disk_num_bytes = num_bytes;
 
 	/* if this is a small write inside eof, kick off defrag */
-	if (num_bytes < 64 * 1024 &&
+	if (num_bytes < SZ_64K &&
 	    (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
 		btrfs_add_inode_defrag(NULL, inode);
 
@@ -1107,7 +1113,7 @@ static noinline void async_cow_submit(struct btrfs_work *work)
 	 * atomic_sub_return implies a barrier for waitqueue_active
 	 */
 	if (atomic_sub_return(nr_pages, &root->fs_info->async_delalloc_pages) <
-	    5 * 1024 * 1024 &&
+	    5 * SZ_1M &&
 	    waitqueue_active(&root->fs_info->async_submit_wait))
 		wake_up(&root->fs_info->async_submit_wait);
 
@@ -1132,7 +1138,7 @@ static int cow_file_range_async(struct inode *inode, struct page *locked_page,
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	unsigned long nr_pages;
 	u64 cur_end;
-	int limit = 10 * 1024 * 1024;
+	int limit = 10 * SZ_1M;
 
 	clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
 			 1, 0, NULL, GFP_NOFS);
@@ -1148,7 +1154,7 @@ static int cow_file_range_async(struct inode *inode, struct page *locked_page,
 		    !btrfs_test_opt(root, FORCE_COMPRESS))
 			cur_end = end;
 		else
-			cur_end = min(end, start + 512 * 1024 - 1);
+			cur_end = min(end, start + SZ_512K - 1);
 
 		async_cow->end = cur_end;
 		INIT_LIST_HEAD(&async_cow->extents);
@@ -1989,7 +1995,7 @@ again:
 	page_start = page_offset(page);
 	page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
 
-	lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0,
+	lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end,
 			 &cached_state);
 
 	/* already ordered? We're done */
@@ -2482,7 +2488,7 @@ static noinline int relink_extent_backref(struct btrfs_path *path,
 	lock_start = backref->file_pos;
 	lock_end = backref->file_pos + backref->num_bytes - 1;
 	lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
-			 0, &cached);
+			 &cached);
 
 	ordered = btrfs_lookup_first_ordered_extent(inode, lock_end);
 	if (ordered) {
@@ -2874,7 +2880,7 @@ static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
 
 	lock_extent_bits(io_tree, ordered_extent->file_offset,
 			 ordered_extent->file_offset + ordered_extent->len - 1,
-			 0, &cached_state);
+			 &cached_state);
 
 	ret = test_range_bit(io_tree, ordered_extent->file_offset,
 			ordered_extent->file_offset + ordered_extent->len - 1,
@@ -3106,55 +3112,47 @@ static int btrfs_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
 				      start, (size_t)(end - start + 1));
 }
 
-struct delayed_iput {
-	struct list_head list;
-	struct inode *inode;
-};
-
-/* JDM: If this is fs-wide, why can't we add a pointer to
- * btrfs_inode instead and avoid the allocation? */
 void btrfs_add_delayed_iput(struct inode *inode)
 {
 	struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
-	struct delayed_iput *delayed;
+	struct btrfs_inode *binode = BTRFS_I(inode);
 
 	if (atomic_add_unless(&inode->i_count, -1, 1))
 		return;
 
-	delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL);
-	delayed->inode = inode;
-
 	spin_lock(&fs_info->delayed_iput_lock);
-	list_add_tail(&delayed->list, &fs_info->delayed_iputs);
+	if (binode->delayed_iput_count == 0) {
+		ASSERT(list_empty(&binode->delayed_iput));
+		list_add_tail(&binode->delayed_iput, &fs_info->delayed_iputs);
+	} else {
+		binode->delayed_iput_count++;
+	}
 	spin_unlock(&fs_info->delayed_iput_lock);
 }
 
 void btrfs_run_delayed_iputs(struct btrfs_root *root)
 {
-	LIST_HEAD(list);
 	struct btrfs_fs_info *fs_info = root->fs_info;
-	struct delayed_iput *delayed;
-	int empty;
-
-	spin_lock(&fs_info->delayed_iput_lock);
-	empty = list_empty(&fs_info->delayed_iputs);
-	spin_unlock(&fs_info->delayed_iput_lock);
-	if (empty)
-		return;
 
 	down_read(&fs_info->delayed_iput_sem);
-
 	spin_lock(&fs_info->delayed_iput_lock);
-	list_splice_init(&fs_info->delayed_iputs, &list);
-	spin_unlock(&fs_info->delayed_iput_lock);
-
-	while (!list_empty(&list)) {
-		delayed = list_entry(list.next, struct delayed_iput, list);
-		list_del(&delayed->list);
-		iput(delayed->inode);
-		kfree(delayed);
+	while (!list_empty(&fs_info->delayed_iputs)) {
+		struct btrfs_inode *inode;
+
+		inode = list_first_entry(&fs_info->delayed_iputs,
+				struct btrfs_inode, delayed_iput);
+		if (inode->delayed_iput_count) {
+			inode->delayed_iput_count--;
+			list_move_tail(&inode->delayed_iput,
+					&fs_info->delayed_iputs);
+		} else {
+			list_del_init(&inode->delayed_iput);
+		}
+		spin_unlock(&fs_info->delayed_iput_lock);
+		iput(&inode->vfs_inode);
+		spin_lock(&fs_info->delayed_iput_lock);
 	}
-
+	spin_unlock(&fs_info->delayed_iput_lock);
 	up_read(&root->fs_info->delayed_iput_sem);
 }
 
@@ -3351,7 +3349,7 @@ int btrfs_orphan_cleanup(struct btrfs_root *root)
 		ret = -ENOMEM;
 		goto out;
 	}
-	path->reada = -1;
+	path->reada = READA_BACK;
 
 	key.objectid = BTRFS_ORPHAN_OBJECTID;
 	key.type = BTRFS_ORPHAN_ITEM_KEY;
@@ -3550,10 +3548,10 @@ static noinline int acls_after_inode_item(struct extent_buffer *leaf,
 	int scanned = 0;
 
 	if (!xattr_access) {
-		xattr_access = btrfs_name_hash(POSIX_ACL_XATTR_ACCESS,
-					strlen(POSIX_ACL_XATTR_ACCESS));
-		xattr_default = btrfs_name_hash(POSIX_ACL_XATTR_DEFAULT,
-					strlen(POSIX_ACL_XATTR_DEFAULT));
+		xattr_access = btrfs_name_hash(XATTR_NAME_POSIX_ACL_ACCESS,
+					strlen(XATTR_NAME_POSIX_ACL_ACCESS));
+		xattr_default = btrfs_name_hash(XATTR_NAME_POSIX_ACL_DEFAULT,
+					strlen(XATTR_NAME_POSIX_ACL_DEFAULT));
 	}
 
 	slot++;
@@ -3774,6 +3772,7 @@ cache_acl:
 		break;
 	case S_IFLNK:
 		inode->i_op = &btrfs_symlink_inode_operations;
+		inode_nohighmem(inode);
 		inode->i_mapping->a_ops = &btrfs_symlink_aops;
 		break;
 	default:
@@ -4317,7 +4316,7 @@ int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
-	path->reada = -1;
+	path->reada = READA_BACK;
 
 	/*
 	 * We want to drop from the next block forward in case this new size is
@@ -4348,7 +4347,7 @@ search_again:
 	 * up a huge file in a single leaf.  Most of the time that
 	 * bytes_deleted is > 0, it will be huge by the time we get here
 	 */
-	if (be_nice && bytes_deleted > 32 * 1024 * 1024) {
+	if (be_nice && bytes_deleted > SZ_32M) {
 		if (btrfs_should_end_transaction(trans, root)) {
 			err = -EAGAIN;
 			goto error;
@@ -4591,7 +4590,7 @@ error:
 
 	btrfs_free_path(path);
 
-	if (be_nice && bytes_deleted > 32 * 1024 * 1024) {
+	if (be_nice && bytes_deleted > SZ_32M) {
 		unsigned long updates = trans->delayed_ref_updates;
 		if (updates) {
 			trans->delayed_ref_updates = 0;
@@ -4668,7 +4667,7 @@ again:
 	}
 	wait_on_page_writeback(page);
 
-	lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state);
+	lock_extent_bits(io_tree, page_start, page_end, &cached_state);
 	set_page_extent_mapped(page);
 
 	ordered = btrfs_lookup_ordered_extent(inode, page_start);
@@ -4799,7 +4798,7 @@ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
 	while (1) {
 		struct btrfs_ordered_extent *ordered;
 
-		lock_extent_bits(io_tree, hole_start, block_end - 1, 0,
+		lock_extent_bits(io_tree, hole_start, block_end - 1,
 				 &cached_state);
 		ordered = btrfs_lookup_ordered_range(inode, hole_start,
 						     block_end - hole_start);
@@ -5111,7 +5110,7 @@ static void evict_inode_truncate_pages(struct inode *inode)
 		end = state->end;
 		spin_unlock(&io_tree->lock);
 
-		lock_extent_bits(io_tree, start, end, 0, &cached_state);
+		lock_extent_bits(io_tree, start, end, &cached_state);
 
 		/*
 		 * If still has DELALLOC flag, the extent didn't reach disk,
@@ -5304,7 +5303,6 @@ void btrfs_evict_inode(struct inode *inode)
 no_delete:
 	btrfs_remove_delayed_node(inode);
 	clear_inode(inode);
-	return;
 }
 
 /*
@@ -5753,7 +5751,7 @@ static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
 	if (!path)
 		return -ENOMEM;
 
-	path->reada = 1;
+	path->reada = READA_FORWARD;
 
 	if (key_type == BTRFS_DIR_INDEX_KEY) {
 		INIT_LIST_HEAD(&ins_list);
@@ -6481,7 +6479,7 @@ out_unlock_inode:
 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
 		      struct dentry *dentry)
 {
-	struct btrfs_trans_handle *trans;
+	struct btrfs_trans_handle *trans = NULL;
 	struct btrfs_root *root = BTRFS_I(dir)->root;
 	struct inode *inode = d_inode(old_dentry);
 	u64 index;
@@ -6507,6 +6505,7 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
 	trans = btrfs_start_transaction(root, 5);
 	if (IS_ERR(trans)) {
 		err = PTR_ERR(trans);
+		trans = NULL;
 		goto fail;
 	}
 
@@ -6540,9 +6539,10 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
 		btrfs_log_new_name(trans, inode, NULL, parent);
 	}
 
-	btrfs_end_transaction(trans, root);
 	btrfs_balance_delayed_items(root);
 fail:
+	if (trans)
+		btrfs_end_transaction(trans, root);
 	if (drop_inode) {
 		inode_dec_link_count(inode);
 		iput(inode);
@@ -6687,7 +6687,7 @@ static int merge_extent_mapping(struct extent_map_tree *em_tree,
 }
 
 static noinline int uncompress_inline(struct btrfs_path *path,
-				      struct inode *inode, struct page *page,
+				      struct page *page,
 				      size_t pg_offset, u64 extent_offset,
 				      struct btrfs_file_extent_item *item)
 {
@@ -6784,7 +6784,7 @@ again:
 		 * Chances are we'll be called again, so go ahead and do
 		 * readahead
 		 */
-		path->reada = 1;
+		path->reada = READA_FORWARD;
 	}
 
 	ret = btrfs_lookup_file_extent(trans, root, path,
@@ -6883,8 +6883,7 @@ next:
 		if (create == 0 && !PageUptodate(page)) {
 			if (btrfs_file_extent_compression(leaf, item) !=
 			    BTRFS_COMPRESS_NONE) {
-				ret = uncompress_inline(path, inode, page,
-							pg_offset,
+				ret = uncompress_inline(path, page, pg_offset,
 							extent_offset, item);
 				if (ret) {
 					err = ret;
@@ -7380,7 +7379,7 @@ static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
 
 	while (1) {
 		lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
-				 0, cached_state);
+				 cached_state);
 		/*
 		 * We're concerned with the entire range that we're going to be
 		 * doing DIO to, so we need to make sure theres no ordered
@@ -7408,25 +7407,21 @@ static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
 			btrfs_start_ordered_extent(inode, ordered, 1);
 			btrfs_put_ordered_extent(ordered);
 		} else {
-			/* Screw you mmap */
-			ret = btrfs_fdatawrite_range(inode, lockstart, lockend);
-			if (ret)
-				break;
-			ret = filemap_fdatawait_range(inode->i_mapping,
-						      lockstart,
-						      lockend);
-			if (ret)
-				break;
-
 			/*
-			 * If we found a page that couldn't be invalidated just
-			 * fall back to buffered.
+			 * We could trigger writeback for this range (and wait
+			 * for it to complete) and then invalidate the pages for
+			 * this range (through invalidate_inode_pages2_range()),
+			 * but that can lead us to a deadlock with a concurrent
+			 * call to readpages() (a buffered read or a defrag call
+			 * triggered a readahead) on a page lock due to an
+			 * ordered dio extent we created before but did not have
+			 * yet a corresponding bio submitted (whence it can not
+			 * complete), which makes readpages() wait for that
+			 * ordered extent to complete while holding a lock on
+			 * that page.
 			 */
-			ret = invalidate_inode_pages2_range(inode->i_mapping,
-					lockstart >> PAGE_CACHE_SHIFT,
-					lockend >> PAGE_CACHE_SHIFT);
-			if (ret)
-				break;
+			ret = -ENOTBLK;
+			break;
 		}
 
 		cond_resched();
@@ -7482,11 +7477,6 @@ static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
 	return em;
 }
 
-struct btrfs_dio_data {
-	u64 outstanding_extents;
-	u64 reserve;
-};
-
 static void adjust_dio_outstanding_extents(struct inode *inode,
 					   struct btrfs_dio_data *dio_data,
 					   const u64 len)
@@ -7670,6 +7660,7 @@ unlock:
 		btrfs_free_reserved_data_space(inode, start, len);
 		WARN_ON(dio_data->reserve < len);
 		dio_data->reserve -= len;
+		dio_data->unsubmitted_oe_range_end = start + len;
 		current->journal_info = dio_data;
 	}
 
@@ -7992,22 +7983,22 @@ static void btrfs_endio_direct_read(struct bio *bio)
 	bio_put(bio);
 }
 
-static void btrfs_endio_direct_write(struct bio *bio)
+static void btrfs_endio_direct_write_update_ordered(struct inode *inode,
+						    const u64 offset,
+						    const u64 bytes,
+						    const int uptodate)
 {
-	struct btrfs_dio_private *dip = bio->bi_private;
-	struct inode *inode = dip->inode;
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_ordered_extent *ordered = NULL;
-	u64 ordered_offset = dip->logical_offset;
-	u64 ordered_bytes = dip->bytes;
-	struct bio *dio_bio;
+	u64 ordered_offset = offset;
+	u64 ordered_bytes = bytes;
 	int ret;
 
 again:
 	ret = btrfs_dec_test_first_ordered_pending(inode, &ordered,
 						   &ordered_offset,
 						   ordered_bytes,
-						   !bio->bi_error);
+						   uptodate);
 	if (!ret)
 		goto out_test;
 
@@ -8020,13 +8011,22 @@ out_test:
 	 * our bio might span multiple ordered extents.  If we haven't
 	 * completed the accounting for the whole dio, go back and try again
 	 */
-	if (ordered_offset < dip->logical_offset + dip->bytes) {
-		ordered_bytes = dip->logical_offset + dip->bytes -
-			ordered_offset;
+	if (ordered_offset < offset + bytes) {
+		ordered_bytes = offset + bytes - ordered_offset;
 		ordered = NULL;
 		goto again;
 	}
-	dio_bio = dip->dio_bio;
+}
+
+static void btrfs_endio_direct_write(struct bio *bio)
+{
+	struct btrfs_dio_private *dip = bio->bi_private;
+	struct bio *dio_bio = dip->dio_bio;
+
+	btrfs_endio_direct_write_update_ordered(dip->inode,
+						dip->logical_offset,
+						dip->bytes,
+						!bio->bi_error);
 
 	kfree(dip);
 
@@ -8334,6 +8334,21 @@ static void btrfs_submit_direct(int rw, struct bio *dio_bio,
 		dip->subio_endio = btrfs_subio_endio_read;
 	}
 
+	/*
+	 * Reset the range for unsubmitted ordered extents (to a 0 length range)
+	 * even if we fail to submit a bio, because in such case we do the
+	 * corresponding error handling below and it must not be done a second
+	 * time by btrfs_direct_IO().
+	 */
+	if (write) {
+		struct btrfs_dio_data *dio_data = current->journal_info;
+
+		dio_data->unsubmitted_oe_range_end = dip->logical_offset +
+			dip->bytes;
+		dio_data->unsubmitted_oe_range_start =
+			dio_data->unsubmitted_oe_range_end;
+	}
+
 	ret = btrfs_submit_direct_hook(rw, dip, skip_sum);
 	if (!ret)
 		return;
@@ -8362,24 +8377,15 @@ free_ordered:
 		dip = NULL;
 		io_bio = NULL;
 	} else {
-		if (write) {
-			struct btrfs_ordered_extent *ordered;
-
-			ordered = btrfs_lookup_ordered_extent(inode,
-							      file_offset);
-			set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
-			/*
-			 * Decrements our ref on the ordered extent and removes
-			 * the ordered extent from the inode's ordered tree,
-			 * doing all the proper resource cleanup such as for the
-			 * reserved space and waking up any waiters for this
-			 * ordered extent (through btrfs_remove_ordered_extent).
-			 */
-			btrfs_finish_ordered_io(ordered);
-		} else {
+		if (write)
+			btrfs_endio_direct_write_update_ordered(inode,
+						file_offset,
+						dio_bio->bi_iter.bi_size,
+						0);
+		else
 			unlock_extent(&BTRFS_I(inode)->io_tree, file_offset,
 			      file_offset + dio_bio->bi_iter.bi_size - 1);
-		}
+
 		dio_bio->bi_error = -EIO;
 		/*
 		 * Releases and cleans up our dio_bio, no need to bio_put()
@@ -8479,6 +8485,8 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
 		 * originally calculated.  Abuse current->journal_info for this.
 		 */
 		dio_data.reserve = round_up(count, root->sectorsize);
+		dio_data.unsubmitted_oe_range_start = (u64)offset;
+		dio_data.unsubmitted_oe_range_end = (u64)offset;
 		current->journal_info = &dio_data;
 	} else if (test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
 				     &BTRFS_I(inode)->runtime_flags)) {
@@ -8497,6 +8505,19 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
 			if (dio_data.reserve)
 				btrfs_delalloc_release_space(inode, offset,
 							     dio_data.reserve);
+			/*
+			 * On error we might have left some ordered extents
+			 * without submitting corresponding bios for them, so
+			 * cleanup them up to avoid other tasks getting them
+			 * and waiting for them to complete forever.
+			 */
+			if (dio_data.unsubmitted_oe_range_start <
+			    dio_data.unsubmitted_oe_range_end)
+				btrfs_endio_direct_write_update_ordered(inode,
+					dio_data.unsubmitted_oe_range_start,
+					dio_data.unsubmitted_oe_range_end -
+					dio_data.unsubmitted_oe_range_start,
+					0);
 		} else if (ret >= 0 && (size_t)ret < count)
 			btrfs_delalloc_release_space(inode, offset,
 						     count - (size_t)ret);
@@ -8534,15 +8555,28 @@ int btrfs_readpage(struct file *file, struct page *page)
 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
 {
 	struct extent_io_tree *tree;
-
+	struct inode *inode = page->mapping->host;
+	int ret;
 
 	if (current->flags & PF_MEMALLOC) {
 		redirty_page_for_writepage(wbc, page);
 		unlock_page(page);
 		return 0;
 	}
+
+	/*
+	 * If we are under memory pressure we will call this directly from the
+	 * VM, we need to make sure we have the inode referenced for the ordered
+	 * extent.  If not just return like we didn't do anything.
+	 */
+	if (!igrab(inode)) {
+		redirty_page_for_writepage(wbc, page);
+		return AOP_WRITEPAGE_ACTIVATE;
+	}
 	tree = &BTRFS_I(page->mapping->host)->io_tree;
-	return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
+	ret = extent_write_full_page(tree, page, btrfs_get_extent, wbc);
+	btrfs_add_delayed_iput(inode);
+	return ret;
 }
 
 static int btrfs_writepages(struct address_space *mapping,
@@ -8614,7 +8648,7 @@ static void btrfs_invalidatepage(struct page *page, unsigned int offset,
 	}
 
 	if (!inode_evicting)
-		lock_extent_bits(tree, page_start, page_end, 0, &cached_state);
+		lock_extent_bits(tree, page_start, page_end, &cached_state);
 	ordered = btrfs_lookup_ordered_extent(inode, page_start);
 	if (ordered) {
 		/*
@@ -8652,7 +8686,7 @@ static void btrfs_invalidatepage(struct page *page, unsigned int offset,
 		btrfs_put_ordered_extent(ordered);
 		if (!inode_evicting) {
 			cached_state = NULL;
-			lock_extent_bits(tree, page_start, page_end, 0,
+			lock_extent_bits(tree, page_start, page_end,
 					 &cached_state);
 		}
 	}
@@ -8750,7 +8784,7 @@ again:
 	}
 	wait_on_page_writeback(page);
 
-	lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state);
+	lock_extent_bits(io_tree, page_start, page_end, &cached_state);
 	set_page_extent_mapped(page);
 
 	/*
@@ -9024,6 +9058,7 @@ struct inode *btrfs_alloc_inode(struct super_block *sb)
 	ei->dir_index = 0;
 	ei->last_unlink_trans = 0;
 	ei->last_log_commit = 0;
+	ei->delayed_iput_count = 0;
 
 	spin_lock_init(&ei->lock);
 	ei->outstanding_extents = 0;
@@ -9048,6 +9083,7 @@ struct inode *btrfs_alloc_inode(struct super_block *sb)
 	mutex_init(&ei->delalloc_mutex);
 	btrfs_ordered_inode_tree_init(&ei->ordered_tree);
 	INIT_LIST_HEAD(&ei->delalloc_inodes);
+	INIT_LIST_HEAD(&ei->delayed_iput);
 	RB_CLEAR_NODE(&ei->rb_node);
 
 	return inode;
@@ -9152,15 +9188,14 @@ void btrfs_destroy_cachep(void)
 		kmem_cache_destroy(btrfs_path_cachep);
 	if (btrfs_free_space_cachep)
 		kmem_cache_destroy(btrfs_free_space_cachep);
-	if (btrfs_delalloc_work_cachep)
-		kmem_cache_destroy(btrfs_delalloc_work_cachep);
 }
 
 int btrfs_init_cachep(void)
 {
 	btrfs_inode_cachep = kmem_cache_create("btrfs_inode",
 			sizeof(struct btrfs_inode), 0,
-			SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
+			SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | SLAB_ACCOUNT,
+			init_once);
 	if (!btrfs_inode_cachep)
 		goto fail;
 
@@ -9188,13 +9223,6 @@ int btrfs_init_cachep(void)
 	if (!btrfs_free_space_cachep)
 		goto fail;
 
-	btrfs_delalloc_work_cachep = kmem_cache_create("btrfs_delalloc_work",
-			sizeof(struct btrfs_delalloc_work), 0,
-			SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
-			NULL);
-	if (!btrfs_delalloc_work_cachep)
-		goto fail;
-
 	return 0;
 fail:
 	btrfs_destroy_cachep();
@@ -9418,14 +9446,10 @@ static void btrfs_run_delalloc_work(struct btrfs_work *work)
 	delalloc_work = container_of(work, struct btrfs_delalloc_work,
 				     work);
 	inode = delalloc_work->inode;
-	if (delalloc_work->wait) {
-		btrfs_wait_ordered_range(inode, 0, (u64)-1);
-	} else {
+	filemap_flush(inode->i_mapping);
+	if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
+				&BTRFS_I(inode)->runtime_flags))
 		filemap_flush(inode->i_mapping);
-		if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
-			     &BTRFS_I(inode)->runtime_flags))
-			filemap_flush(inode->i_mapping);
-	}
 
 	if (delalloc_work->delay_iput)
 		btrfs_add_delayed_iput(inode);
@@ -9435,18 +9459,17 @@ static void btrfs_run_delalloc_work(struct btrfs_work *work)
 }
 
 struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode,
-						    int wait, int delay_iput)
+						    int delay_iput)
 {
 	struct btrfs_delalloc_work *work;
 
-	work = kmem_cache_zalloc(btrfs_delalloc_work_cachep, GFP_NOFS);
+	work = kmalloc(sizeof(*work), GFP_NOFS);
 	if (!work)
 		return NULL;
 
 	init_completion(&work->completion);
 	INIT_LIST_HEAD(&work->list);
 	work->inode = inode;
-	work->wait = wait;
 	work->delay_iput = delay_iput;
 	WARN_ON_ONCE(!inode);
 	btrfs_init_work(&work->work, btrfs_flush_delalloc_helper,
@@ -9458,7 +9481,7 @@ struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode,
 void btrfs_wait_and_free_delalloc_work(struct btrfs_delalloc_work *work)
 {
 	wait_for_completion(&work->completion);
-	kmem_cache_free(btrfs_delalloc_work_cachep, work);
+	kfree(work);
 }
 
 /*
@@ -9494,7 +9517,7 @@ static int __start_delalloc_inodes(struct btrfs_root *root, int delay_iput,
 		}
 		spin_unlock(&root->delalloc_lock);
 
-		work = btrfs_alloc_delalloc_work(inode, 0, delay_iput);
+		work = btrfs_alloc_delalloc_work(inode, delay_iput);
 		if (!work) {
 			if (delay_iput)
 				btrfs_add_delayed_iput(inode);
@@ -9636,9 +9659,11 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
 	/*
 	 * 2 items for inode item and ref
 	 * 2 items for dir items
+	 * 1 item for updating parent inode item
+	 * 1 item for the inline extent item
 	 * 1 item for xattr if selinux is on
 	 */
-	trans = btrfs_start_transaction(root, 5);
+	trans = btrfs_start_transaction(root, 7);
 	if (IS_ERR(trans))
 		return PTR_ERR(trans);
 
@@ -9669,10 +9694,6 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
 	if (err)
 		goto out_unlock_inode;
 
-	err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
-	if (err)
-		goto out_unlock_inode;
-
 	path = btrfs_alloc_path();
 	if (!path) {
 		err = -ENOMEM;
@@ -9705,10 +9726,18 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
 	btrfs_free_path(path);
 
 	inode->i_op = &btrfs_symlink_inode_operations;
+	inode_nohighmem(inode);
 	inode->i_mapping->a_ops = &btrfs_symlink_aops;
 	inode_set_bytes(inode, name_len);
 	btrfs_i_size_write(inode, name_len);
 	err = btrfs_update_inode(trans, root, inode);
+	/*
+	 * Last step, add directory indexes for our symlink inode. This is the
+	 * last step to avoid extra cleanup of these indexes if an error happens
+	 * elsewhere above.
+	 */
+	if (!err)
+		err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
 	if (err) {
 		drop_inode = 1;
 		goto out_unlock_inode;
@@ -9759,7 +9788,7 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
 			}
 		}
 
-		cur_bytes = min(num_bytes, 256ULL * 1024 * 1024);
+		cur_bytes = min_t(u64, num_bytes, SZ_256M);
 		cur_bytes = max(cur_bytes, min_size);
 		/*
 		 * If we are severely fragmented we could end up with really
@@ -9994,7 +10023,7 @@ static const struct inode_operations btrfs_dir_inode_operations = {
 	.setattr	= btrfs_setattr,
 	.mknod		= btrfs_mknod,
 	.setxattr	= btrfs_setxattr,
-	.getxattr	= btrfs_getxattr,
+	.getxattr	= generic_getxattr,
 	.listxattr	= btrfs_listxattr,
 	.removexattr	= btrfs_removexattr,
 	.permission	= btrfs_permission,
@@ -10023,7 +10052,7 @@ static const struct file_operations btrfs_dir_file_operations = {
 	.fsync		= btrfs_sync_file,
 };
 
-static struct extent_io_ops btrfs_extent_io_ops = {
+static const struct extent_io_ops btrfs_extent_io_ops = {
 	.fill_delalloc = run_delalloc_range,
 	.submit_bio_hook = btrfs_submit_bio_hook,
 	.merge_bio_hook = btrfs_merge_bio_hook,
@@ -10071,7 +10100,7 @@ static const struct inode_operations btrfs_file_inode_operations = {
 	.getattr	= btrfs_getattr,
 	.setattr	= btrfs_setattr,
 	.setxattr	= btrfs_setxattr,
-	.getxattr	= btrfs_getxattr,
+	.getxattr	= generic_getxattr,
 	.listxattr      = btrfs_listxattr,
 	.removexattr	= btrfs_removexattr,
 	.permission	= btrfs_permission,
@@ -10085,7 +10114,7 @@ static const struct inode_operations btrfs_special_inode_operations = {
 	.setattr	= btrfs_setattr,
 	.permission	= btrfs_permission,
 	.setxattr	= btrfs_setxattr,
-	.getxattr	= btrfs_getxattr,
+	.getxattr	= generic_getxattr,
 	.listxattr	= btrfs_listxattr,
 	.removexattr	= btrfs_removexattr,
 	.get_acl	= btrfs_get_acl,
@@ -10094,13 +10123,12 @@ static const struct inode_operations btrfs_special_inode_operations = {
 };
 static const struct inode_operations btrfs_symlink_inode_operations = {
 	.readlink	= generic_readlink,
-	.follow_link	= page_follow_link_light,
-	.put_link	= page_put_link,
+	.get_link	= page_get_link,
 	.getattr	= btrfs_getattr,
 	.setattr	= btrfs_setattr,
 	.permission	= btrfs_permission,
 	.setxattr	= btrfs_setxattr,
-	.getxattr	= btrfs_getxattr,
+	.getxattr	= generic_getxattr,
 	.listxattr	= btrfs_listxattr,
 	.removexattr	= btrfs_removexattr,
 	.update_time	= btrfs_update_time,