1 files changed, 303 insertions, 175 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 488edca8333a..a9322601ab5c 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -393,34 +393,13 @@ void btrfs_inode_unlock(struct btrfs_inode *inode, unsigned int ilock_flags)
  * extent (btrfs_finish_ordered_io()).
  */
 static inline void btrfs_cleanup_ordered_extents(struct btrfs_inode *inode,
-						 struct folio *locked_folio,
 						 u64 offset, u64 bytes)
 {
 	unsigned long index = offset >> PAGE_SHIFT;
 	unsigned long end_index = (offset + bytes - 1) >> PAGE_SHIFT;
-	u64 page_start = 0, page_end = 0;
 	struct folio *folio;
 
-	if (locked_folio) {
-		page_start = folio_pos(locked_folio);
-		page_end = page_start + folio_size(locked_folio) - 1;
-	}
-
 	while (index <= end_index) {
-		/*
-		 * For locked page, we will call btrfs_mark_ordered_io_finished
-		 * through btrfs_mark_ordered_io_finished() on it
-		 * in run_delalloc_range() for the error handling, which will
-		 * clear page Ordered and run the ordered extent accounting.
-		 *
-		 * Here we can't just clear the Ordered bit, or
-		 * btrfs_mark_ordered_io_finished() would skip the accounting
-		 * for the page range, and the ordered extent will never finish.
-		 */
-		if (locked_folio && index == (page_start >> PAGE_SHIFT)) {
-			index++;
-			continue;
-		}
 		folio = filemap_get_folio(inode->vfs_inode.i_mapping, index);
 		index++;
 		if (IS_ERR(folio))
@@ -436,23 +415,6 @@ static inline void btrfs_cleanup_ordered_extents(struct btrfs_inode *inode,
 		folio_put(folio);
 	}
 
-	if (locked_folio) {
-		/* The locked page covers the full range, nothing needs to be done */
-		if (bytes + offset <= page_start + folio_size(locked_folio))
-			return;
-		/*
-		 * In case this page belongs to the delalloc range being
-		 * instantiated then skip it, since the first page of a range is
-		 * going to be properly cleaned up by the caller of
-		 * run_delalloc_range
-		 */
-		if (page_start >= offset && page_end <= (offset + bytes - 1)) {
-			bytes = offset + bytes - folio_pos(locked_folio) -
-				folio_size(locked_folio);
-			offset = folio_pos(locked_folio) + folio_size(locked_folio);
-		}
-	}
-
 	return btrfs_mark_ordered_io_finished(inode, NULL, offset, bytes, false);
 }
 
@@ -564,7 +526,6 @@ static int insert_inline_extent(struct btrfs_trans_handle *trans,
 		kunmap_local(kaddr);
 		folio_put(folio);
 	}
-	btrfs_mark_buffer_dirty(trans, leaf);
 	btrfs_release_path(path);
 
 	/*
@@ -1129,19 +1090,14 @@ static void submit_uncompressed_range(struct btrfs_inode *inode,
 			       &wbc, false);
 	wbc_detach_inode(&wbc);
 	if (ret < 0) {
-		btrfs_cleanup_ordered_extents(inode, locked_folio,
-					      start, end - start + 1);
-		if (locked_folio) {
-			const u64 page_start = folio_pos(locked_folio);
-
-			folio_start_writeback(locked_folio);
-			folio_end_writeback(locked_folio);
-			btrfs_mark_ordered_io_finished(inode, locked_folio,
-						       page_start, PAGE_SIZE,
-						       !ret);
-			mapping_set_error(locked_folio->mapping, ret);
-			folio_unlock(locked_folio);
-		}
+		btrfs_cleanup_ordered_extents(inode, start, end - start + 1);
+		if (locked_folio)
+			btrfs_folio_end_lock(inode->root->fs_info, locked_folio,
+					     start, async_extent->ram_size);
+		btrfs_err_rl(inode->root->fs_info,
+			"%s failed, root=%llu inode=%llu start=%llu len=%llu: %d",
+			     __func__, btrfs_root_id(inode->root),
+			     btrfs_ino(inode), start, async_extent->ram_size, ret);
 	}
 }
 
@@ -1373,6 +1329,17 @@ static noinline int cow_file_range(struct btrfs_inode *inode,
 	alloc_hint = btrfs_get_extent_allocation_hint(inode, start, num_bytes);
 
 	/*
+	 * We're not doing compressed IO, don't unlock the first page (which
+	 * the caller expects to stay locked), don't clear any dirty bits and
+	 * don't set any writeback bits.
+	 *
+	 * Do set the Ordered (Private2) bit so we know this page was properly
+	 * setup for writepage.
+	 */
+	page_ops = (keep_locked ? 0 : PAGE_UNLOCK);
+	page_ops |= PAGE_SET_ORDERED;
+
+	/*
 	 * Relocation relies on the relocated extents to have exactly the same
 	 * size as the original extents. Normally writeback for relocation data
 	 * extents follows a NOCOW path because relocation preallocates the
@@ -1431,6 +1398,10 @@ static noinline int cow_file_range(struct btrfs_inode *inode,
 		file_extent.offset = 0;
 		file_extent.compression = BTRFS_COMPRESS_NONE;
 
+		/*
+		 * Locked range will be released either during error clean up or
+		 * after the whole range is finished.
+		 */
 		lock_extent(&inode->io_tree, start, start + cur_alloc_size - 1,
 			    &cached);
 
@@ -1476,21 +1447,6 @@ static noinline int cow_file_range(struct btrfs_inode *inode,
 
 		btrfs_dec_block_group_reservations(fs_info, ins.objectid);
 
-		/*
-		 * We're not doing compressed IO, don't unlock the first page
-		 * (which the caller expects to stay locked), don't clear any
-		 * dirty bits and don't set any writeback bits
-		 *
-		 * Do set the Ordered flag so we know this page was
-		 * properly setup for writepage.
-		 */
-		page_ops = (keep_locked ? 0 : PAGE_UNLOCK);
-		page_ops |= PAGE_SET_ORDERED;
-
-		extent_clear_unlock_delalloc(inode, start, start + cur_alloc_size - 1,
-					     locked_folio, &cached,
-					     EXTENT_LOCKED | EXTENT_DELALLOC,
-					     page_ops);
 		if (num_bytes < cur_alloc_size)
 			num_bytes = 0;
 		else
@@ -1507,6 +1463,8 @@ static noinline int cow_file_range(struct btrfs_inode *inode,
 		if (ret)
 			goto out_unlock;
 	}
+	extent_clear_unlock_delalloc(inode, orig_start, end, locked_folio, &cached,
+				     EXTENT_LOCKED | EXTENT_DELALLOC, page_ops);
 done:
 	if (done_offset)
 		*done_offset = end;
@@ -1527,35 +1485,30 @@ out_unlock:
 	 * We process each region below.
 	 */
 
-	clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW |
-		EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV;
-	page_ops = PAGE_UNLOCK | PAGE_START_WRITEBACK | PAGE_END_WRITEBACK;
-
 	/*
 	 * For the range (1). We have already instantiated the ordered extents
 	 * for this region. They are cleaned up by
 	 * btrfs_cleanup_ordered_extents() in e.g,
-	 * btrfs_run_delalloc_range(). EXTENT_LOCKED | EXTENT_DELALLOC are
-	 * already cleared in the above loop. And, EXTENT_DELALLOC_NEW |
-	 * EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV are handled by the cleanup
-	 * function.
+	 * btrfs_run_delalloc_range().
+	 * EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV
+	 * are also handled by the cleanup function.
 	 *
-	 * However, in case of @keep_locked, we still need to unlock the pages
-	 * (except @locked_folio) to ensure all the pages are unlocked.
+	 * So here we only clear EXTENT_LOCKED and EXTENT_DELALLOC flag, and
+	 * finish the writeback of the involved folios, which will be never submitted.
 	 */
-	if (keep_locked && orig_start < start) {
+	if (orig_start < start) {
+		clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC;
+		page_ops = PAGE_UNLOCK | PAGE_START_WRITEBACK | PAGE_END_WRITEBACK;
+
 		if (!locked_folio)
 			mapping_set_error(inode->vfs_inode.i_mapping, ret);
 		extent_clear_unlock_delalloc(inode, orig_start, start - 1,
-					     locked_folio, NULL, 0, page_ops);
+					     locked_folio, NULL, clear_bits, page_ops);
 	}
 
-	/*
-	 * At this point we're unlocked, we want to make sure we're only
-	 * clearing these flags under the extent lock, so lock the rest of the
-	 * range and clear everything up.
-	 */
-	lock_extent(&inode->io_tree, start, end, NULL);
+	clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW |
+		     EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV;
+	page_ops = PAGE_UNLOCK | PAGE_START_WRITEBACK | PAGE_END_WRITEBACK;
 
 	/*
 	 * For the range (2). If we reserved an extent for our delalloc range
@@ -1589,6 +1542,10 @@ out_unlock:
 		btrfs_qgroup_free_data(inode, NULL, start + cur_alloc_size,
 				       end - start - cur_alloc_size + 1, NULL);
 	}
+	btrfs_err_rl(fs_info,
+		     "%s failed, root=%llu inode=%llu start=%llu len=%llu: %d",
+		     __func__, btrfs_root_id(inode->root),
+		     btrfs_ino(inode), orig_start, end + 1 - orig_start, ret);
 	return ret;
 }
 
@@ -1809,7 +1766,7 @@ static int fallback_to_cow(struct btrfs_inode *inode,
 			bytes = range_bytes;
 
 		spin_lock(&sinfo->lock);
-		btrfs_space_info_update_bytes_may_use(fs_info, sinfo, bytes);
+		btrfs_space_info_update_bytes_may_use(sinfo, bytes);
 		spin_unlock(&sinfo->lock);
 
 		if (count > 0)
@@ -1837,7 +1794,6 @@ struct can_nocow_file_extent_args {
 	/* End file offset (inclusive) of the range we want to NOCOW. */
 	u64 end;
 	bool writeback_path;
-	bool strict;
 	/*
 	 * Free the path passed to can_nocow_file_extent() once it's not needed
 	 * anymore.
@@ -1892,8 +1848,7 @@ static int can_nocow_file_extent(struct btrfs_path *path,
 	 * for its subvolume was created, then this implies the extent is shared,
 	 * hence we must COW.
 	 */
-	if (!args->strict &&
-	    btrfs_file_extent_generation(leaf, fi) <=
+	if (btrfs_file_extent_generation(leaf, fi) <=
 	    btrfs_root_last_snapshot(&root->root_item))
 		goto out;
 
@@ -1922,9 +1877,8 @@ static int can_nocow_file_extent(struct btrfs_path *path,
 	 */
 	btrfs_release_path(path);
 
-	ret = btrfs_cross_ref_exist(root, btrfs_ino(inode),
-				    key->offset - args->file_extent.offset,
-				    args->file_extent.disk_bytenr, args->strict, path);
+	ret = btrfs_cross_ref_exist(inode, key->offset - args->file_extent.offset,
+				    args->file_extent.disk_bytenr, path);
 	WARN_ON_ONCE(ret > 0 && is_freespace_inode);
 	if (ret != 0)
 		goto out;
@@ -1971,6 +1925,53 @@ static int can_nocow_file_extent(struct btrfs_path *path,
 }
 
 /*
+ * Cleanup the dirty folios which will never be submitted due to error.
+ *
+ * When running a delalloc range, we may need to split the ranges (due to
+ * fragmentation or NOCOW). If we hit an error in the later part, we will error
+ * out and previously successfully executed range will never be submitted, thus
+ * we have to cleanup those folios by clearing their dirty flag, starting and
+ * finishing the writeback.
+ */
+static void cleanup_dirty_folios(struct btrfs_inode *inode,
+				 struct folio *locked_folio,
+				 u64 start, u64 end, int error)
+{
+	struct btrfs_fs_info *fs_info = inode->root->fs_info;
+	struct address_space *mapping = inode->vfs_inode.i_mapping;
+	pgoff_t start_index = start >> PAGE_SHIFT;
+	pgoff_t end_index = end >> PAGE_SHIFT;
+	u32 len;
+
+	ASSERT(end + 1 - start < U32_MAX);
+	ASSERT(IS_ALIGNED(start, fs_info->sectorsize) &&
+	       IS_ALIGNED(end + 1, fs_info->sectorsize));
+	len = end + 1 - start;
+
+	/*
+	 * Handle the locked folio first.
+	 * The btrfs_folio_clamp_*() helpers can handle range out of the folio case.
+	 */
+	btrfs_folio_clamp_finish_io(fs_info, locked_folio, start, len);
+
+	for (pgoff_t index = start_index; index <= end_index; index++) {
+		struct folio *folio;
+
+		/* Already handled at the beginning. */
+		if (index == locked_folio->index)
+			continue;
+		folio = __filemap_get_folio(mapping, index, FGP_LOCK, GFP_NOFS);
+		/* Cache already dropped, no need to do any cleanup. */
+		if (IS_ERR(folio))
+			continue;
+		btrfs_folio_clamp_finish_io(fs_info, locked_folio, start, len);
+		folio_unlock(folio);
+		folio_put(folio);
+	}
+	mapping_set_error(mapping, error);
+}
+
+/*
  * when nowcow writeback call back.  This checks for snapshots or COW copies
  * of the extents that exist in the file, and COWs the file as required.
  *
@@ -1985,6 +1986,11 @@ static noinline int run_delalloc_nocow(struct btrfs_inode *inode,
 	struct btrfs_root *root = inode->root;
 	struct btrfs_path *path;
 	u64 cow_start = (u64)-1;
+	/*
+	 * If not 0, represents the inclusive end of the last fallback_to_cow()
+	 * range. Only for error handling.
+	 */
+	u64 cow_end = 0;
 	u64 cur_offset = start;
 	int ret;
 	bool check_prev = true;
@@ -2145,6 +2151,7 @@ must_cow:
 					      found_key.offset - 1);
 			cow_start = (u64)-1;
 			if (ret) {
+				cow_end = found_key.offset - 1;
 				btrfs_dec_nocow_writers(nocow_bg);
 				goto error;
 			}
@@ -2218,11 +2225,12 @@ must_cow:
 		cow_start = cur_offset;
 
 	if (cow_start != (u64)-1) {
-		cur_offset = end;
 		ret = fallback_to_cow(inode, locked_folio, cow_start, end);
 		cow_start = (u64)-1;
-		if (ret)
+		if (ret) {
+			cow_end = end;
 			goto error;
+		}
 	}
 
 	btrfs_free_path(path);
@@ -2230,12 +2238,41 @@ must_cow:
 
 error:
 	/*
+	 * There are several error cases:
+	 *
+	 * 1) Failed without falling back to COW
+	 *    start         cur_offset             end
+	 *    |/////////////|                      |
+	 *
+	 *    For range [start, cur_offset) the folios are already unlocked (except
+	 *    @locked_folio), EXTENT_DELALLOC already removed.
+	 *    Only need to clear the dirty flag as they will never be submitted.
+	 *    Ordered extent and extent maps are handled by
+	 *    btrfs_mark_ordered_io_finished() inside run_delalloc_range().
+	 *
+	 * 2) Failed with error from fallback_to_cow()
+	 *    start         cur_offset  cow_end    end
+	 *    |/////////////|-----------|          |
+	 *
+	 *    For range [start, cur_offset) it's the same as case 1).
+	 *    But for range [cur_offset, cow_end), the folios have dirty flag
+	 *    cleared and unlocked, EXTENT_DEALLLOC cleared by cow_file_range().
+	 *
+	 *    Thus we should not call extent_clear_unlock_delalloc() on range
+	 *    [cur_offset, cow_end), as the folios are already unlocked.
+	 *
+	 * So clear the folio dirty flags for [start, cur_offset) first.
+	 */
+	if (cur_offset > start)
+		cleanup_dirty_folios(inode, locked_folio, start, cur_offset - 1, ret);
+
+	/*
 	 * If an error happened while a COW region is outstanding, cur_offset
-	 * needs to be reset to cow_start to ensure the COW region is unlocked
-	 * as well.
+	 * needs to be reset to @cow_end + 1 to skip the COW range, as
+	 * cow_file_range() will do the proper cleanup at error.
 	 */
-	if (cow_start != (u64)-1)
-		cur_offset = cow_start;
+	if (cow_end)
+		cur_offset = cow_end + 1;
 
 	/*
 	 * We need to lock the extent here because we're clearing DELALLOC and
@@ -2255,6 +2292,10 @@ error:
 		btrfs_qgroup_free_data(inode, NULL, cur_offset, end - cur_offset + 1, NULL);
 	}
 	btrfs_free_path(path);
+	btrfs_err_rl(fs_info,
+		     "%s failed, root=%llu inode=%llu start=%llu len=%llu: %d",
+		     __func__, btrfs_root_id(inode->root),
+		     btrfs_ino(inode), start, end + 1 - start, ret);
 	return ret;
 }
 
@@ -2305,8 +2346,7 @@ int btrfs_run_delalloc_range(struct btrfs_inode *inode, struct folio *locked_fol
 
 out:
 	if (ret < 0)
-		btrfs_cleanup_ordered_extents(inode, locked_folio, start,
-					      end - start + 1);
+		btrfs_cleanup_ordered_extents(inode, start, end - start + 1);
 	return ret;
 }
 
@@ -2921,7 +2961,6 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
 			btrfs_item_ptr_offset(leaf, path->slots[0]),
 			sizeof(struct btrfs_file_extent_item));
 
-	btrfs_mark_buffer_dirty(trans, leaf);
 	btrfs_release_path(path);
 
 	/*
@@ -4085,7 +4124,6 @@ static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans,
 				    struct btrfs_inode_item);
 
 	fill_inode_item(trans, leaf, inode_item, &inode->vfs_inode);
-	btrfs_mark_buffer_dirty(trans, leaf);
 	btrfs_set_inode_last_trans(trans, inode);
 	ret = 0;
 failed:
@@ -6380,7 +6418,6 @@ int btrfs_create_new_inode(struct btrfs_trans_handle *trans,
 		}
 	}
 
-	btrfs_mark_buffer_dirty(trans, path->nodes[0]);
 	/*
 	 * We don't need the path anymore, plus inheriting properties, adding
 	 * ACLs, security xattrs, orphan item or adding the link, will result in
@@ -7011,8 +7048,6 @@ static bool btrfs_extent_readonly(struct btrfs_fs_info *fs_info, u64 bytenr)
  * @orig_start:	(optional) Return the original file offset of the file extent
  * @orig_len:	(optional) Return the original on-disk length of the file extent
  * @ram_bytes:	(optional) Return the ram_bytes of the file extent
- * @strict:	if true, omit optimizations that might force us into unnecessary
- *		cow. e.g., don't trust generation number.
  *
  * Return:
  * >0	and update @len if we can do nocow write
@@ -7024,7 +7059,7 @@ static bool btrfs_extent_readonly(struct btrfs_fs_info *fs_info, u64 bytenr)
  */
 noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
 			      struct btrfs_file_extent *file_extent,
-			      bool nowait, bool strict)
+			      bool nowait)
 {
 	struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
 	struct can_nocow_file_extent_args nocow_args = { 0 };
@@ -7077,7 +7112,6 @@ noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
 
 	nocow_args.start = offset;
 	nocow_args.end = offset + *len - 1;
-	nocow_args.strict = strict;
 	nocow_args.free_path = true;
 
 	ret = can_nocow_file_extent(path, &key, BTRFS_I(inode), &nocow_args);
@@ -8027,31 +8061,45 @@ static int btrfs_rename_exchange(struct inode *old_dir,
 	/* src is a subvolume */
 	if (old_ino == BTRFS_FIRST_FREE_OBJECTID) {
 		ret = btrfs_unlink_subvol(trans, BTRFS_I(old_dir), old_dentry);
+		if (ret) {
+			btrfs_abort_transaction(trans, ret);
+			goto out_fail;
+		}
 	} else { /* src is an inode */
 		ret = __btrfs_unlink_inode(trans, BTRFS_I(old_dir),
 					   BTRFS_I(old_dentry->d_inode),
 					   old_name, &old_rename_ctx);
-		if (!ret)
-			ret = btrfs_update_inode(trans, BTRFS_I(old_inode));
-	}
-	if (ret) {
-		btrfs_abort_transaction(trans, ret);
-		goto out_fail;
+		if (ret) {
+			btrfs_abort_transaction(trans, ret);
+			goto out_fail;
+		}
+		ret = btrfs_update_inode(trans, BTRFS_I(old_inode));
+		if (ret) {
+			btrfs_abort_transaction(trans, ret);
+			goto out_fail;
+		}
 	}
 
 	/* dest is a subvolume */
 	if (new_ino == BTRFS_FIRST_FREE_OBJECTID) {
 		ret = btrfs_unlink_subvol(trans, BTRFS_I(new_dir), new_dentry);
+		if (ret) {
+			btrfs_abort_transaction(trans, ret);
+			goto out_fail;
+		}
 	} else { /* dest is an inode */
 		ret = __btrfs_unlink_inode(trans, BTRFS_I(new_dir),
 					   BTRFS_I(new_dentry->d_inode),
 					   new_name, &new_rename_ctx);
-		if (!ret)
-			ret = btrfs_update_inode(trans, BTRFS_I(new_inode));
-	}
-	if (ret) {
-		btrfs_abort_transaction(trans, ret);
-		goto out_fail;
+		if (ret) {
+			btrfs_abort_transaction(trans, ret);
+			goto out_fail;
+		}
+		ret = btrfs_update_inode(trans, BTRFS_I(new_inode));
+		if (ret) {
+			btrfs_abort_transaction(trans, ret);
+			goto out_fail;
+		}
 	}
 
 	ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode),
@@ -8287,16 +8335,23 @@ static int btrfs_rename(struct mnt_idmap *idmap,
 
 	if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
 		ret = btrfs_unlink_subvol(trans, BTRFS_I(old_dir), old_dentry);
+		if (ret) {
+			btrfs_abort_transaction(trans, ret);
+			goto out_fail;
+		}
 	} else {
 		ret = __btrfs_unlink_inode(trans, BTRFS_I(old_dir),
 					   BTRFS_I(d_inode(old_dentry)),
 					   &old_fname.disk_name, &rename_ctx);
-		if (!ret)
-			ret = btrfs_update_inode(trans, BTRFS_I(old_inode));
-	}
-	if (ret) {
-		btrfs_abort_transaction(trans, ret);
-		goto out_fail;
+		if (ret) {
+			btrfs_abort_transaction(trans, ret);
+			goto out_fail;
+		}
+		ret = btrfs_update_inode(trans, BTRFS_I(old_inode));
+		if (ret) {
+			btrfs_abort_transaction(trans, ret);
+			goto out_fail;
+		}
 	}
 
 	if (new_inode) {
@@ -8304,18 +8359,27 @@ static int btrfs_rename(struct mnt_idmap *idmap,
 		if (unlikely(btrfs_ino(BTRFS_I(new_inode)) ==
 			     BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
 			ret = btrfs_unlink_subvol(trans, BTRFS_I(new_dir), new_dentry);
+			if (ret) {
+				btrfs_abort_transaction(trans, ret);
+				goto out_fail;
+			}
 			BUG_ON(new_inode->i_nlink == 0);
 		} else {
 			ret = btrfs_unlink_inode(trans, BTRFS_I(new_dir),
 						 BTRFS_I(d_inode(new_dentry)),
 						 &new_fname.disk_name);
+			if (ret) {
+				btrfs_abort_transaction(trans, ret);
+				goto out_fail;
+			}
 		}
-		if (!ret && new_inode->i_nlink == 0)
+		if (new_inode->i_nlink == 0) {
 			ret = btrfs_orphan_add(trans,
 					BTRFS_I(d_inode(new_dentry)));
-		if (ret) {
-			btrfs_abort_transaction(trans, ret);
-			goto out_fail;
+			if (ret) {
+				btrfs_abort_transaction(trans, ret);
+				goto out_fail;
+			}
 		}
 	}
 
@@ -8655,7 +8719,6 @@ static int btrfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
 
 	ptr = btrfs_file_extent_inline_start(ei);
 	write_extent_buffer(leaf, symname, ptr, name_len);
-	btrfs_mark_buffer_dirty(trans, leaf);
 	btrfs_free_path(path);
 
 	d_instantiate_new(dentry, inode);
@@ -9078,9 +9141,9 @@ out:
 }
 
 struct btrfs_encoded_read_private {
-	wait_queue_head_t wait;
+	struct completion done;
 	void *uring_ctx;
-	atomic_t pending;
+	refcount_t pending_refs;
 	blk_status_t status;
 };
 
@@ -9099,14 +9162,14 @@ static void btrfs_encoded_read_endio(struct btrfs_bio *bbio)
 		 */
 		WRITE_ONCE(priv->status, bbio->bio.bi_status);
 	}
-	if (atomic_dec_and_test(&priv->pending)) {
+	if (refcount_dec_and_test(&priv->pending_refs)) {
 		int err = blk_status_to_errno(READ_ONCE(priv->status));
 
 		if (priv->uring_ctx) {
 			btrfs_uring_read_extent_endio(priv->uring_ctx, err);
 			kfree(priv);
 		} else {
-			wake_up(&priv->wait);
+			complete(&priv->done);
 		}
 	}
 	bio_put(&bbio->bio);
@@ -9126,8 +9189,8 @@ int btrfs_encoded_read_regular_fill_pages(struct btrfs_inode *inode,
 	if (!priv)
 		return -ENOMEM;
 
-	init_waitqueue_head(&priv->wait);
-	atomic_set(&priv->pending, 1);
+	init_completion(&priv->done);
+	refcount_set(&priv->pending_refs, 1);
 	priv->status = 0;
 	priv->uring_ctx = uring_ctx;
 
@@ -9140,7 +9203,7 @@ int btrfs_encoded_read_regular_fill_pages(struct btrfs_inode *inode,
 		size_t bytes = min_t(u64, disk_io_size, PAGE_SIZE);
 
 		if (bio_add_page(&bbio->bio, pages[i], bytes, 0) < bytes) {
-			atomic_inc(&priv->pending);
+			refcount_inc(&priv->pending_refs);
 			btrfs_submit_bbio(bbio, 0);
 
 			bbio = btrfs_bio_alloc(BIO_MAX_VECS, REQ_OP_READ, fs_info,
@@ -9155,11 +9218,11 @@ int btrfs_encoded_read_regular_fill_pages(struct btrfs_inode *inode,
 		disk_io_size -= bytes;
 	} while (disk_io_size);
 
-	atomic_inc(&priv->pending);
+	refcount_inc(&priv->pending_refs);
 	btrfs_submit_bbio(bbio, 0);
 
 	if (uring_ctx) {
-		if (atomic_dec_return(&priv->pending) == 0) {
+		if (refcount_dec_and_test(&priv->pending_refs)) {
 			ret = blk_status_to_errno(READ_ONCE(priv->status));
 			btrfs_uring_read_extent_endio(uring_ctx, ret);
 			kfree(priv);
@@ -9168,8 +9231,8 @@ int btrfs_encoded_read_regular_fill_pages(struct btrfs_inode *inode,
 
 		return -EIOCBQUEUED;
 	} else {
-		if (atomic_dec_return(&priv->pending) != 0)
-			io_wait_event(priv->wait, !atomic_read(&priv->pending));
+		if (!refcount_dec_and_test(&priv->pending_refs))
+			wait_for_completion_io(&priv->done);
 		/* See btrfs_encoded_read_endio() for ordering. */
 		ret = blk_status_to_errno(READ_ONCE(priv->status));
 		kfree(priv);
@@ -9799,15 +9862,25 @@ static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 	struct extent_state *cached_state = NULL;
-	struct extent_map *em = NULL;
 	struct btrfs_chunk_map *map = NULL;
 	struct btrfs_device *device = NULL;
 	struct btrfs_swap_info bsi = {
 		.lowest_ppage = (sector_t)-1ULL,
 	};
+	struct btrfs_backref_share_check_ctx *backref_ctx = NULL;
+	struct btrfs_path *path = NULL;
 	int ret = 0;
 	u64 isize;
-	u64 start;
+	u64 prev_extent_end = 0;
+
+	/*
+	 * Acquire the inode's mmap lock to prevent races with memory mapped
+	 * writes, as they could happen after we flush delalloc below and before
+	 * we lock the extent range further below. The inode was already locked
+	 * up in the call chain.
+	 */
+	btrfs_assert_inode_locked(BTRFS_I(inode));
+	down_write(&BTRFS_I(inode)->i_mmap_lock);
 
 	/*
 	 * If the swap file was just created, make sure delalloc is done. If the
@@ -9816,22 +9889,32 @@ static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
 	 */
 	ret = btrfs_wait_ordered_range(BTRFS_I(inode), 0, (u64)-1);
 	if (ret)
-		return ret;
+		goto out_unlock_mmap;
 
 	/*
 	 * The inode is locked, so these flags won't change after we check them.
 	 */
 	if (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS) {
 		btrfs_warn(fs_info, "swapfile must not be compressed");
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_unlock_mmap;
 	}
 	if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)) {
 		btrfs_warn(fs_info, "swapfile must not be copy-on-write");
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_unlock_mmap;
 	}
 	if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
 		btrfs_warn(fs_info, "swapfile must not be checksummed");
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_unlock_mmap;
+	}
+
+	path = btrfs_alloc_path();
+	backref_ctx = btrfs_alloc_backref_share_check_ctx();
+	if (!path || !backref_ctx) {
+		ret = -ENOMEM;
+		goto out_unlock_mmap;
 	}
 
 	/*
@@ -9846,7 +9929,8 @@ static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
 	if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_SWAP_ACTIVATE)) {
 		btrfs_warn(fs_info,
 	   "cannot activate swapfile while exclusive operation is running");
-		return -EBUSY;
+		ret = -EBUSY;
+		goto out_unlock_mmap;
 	}
 
 	/*
@@ -9860,7 +9944,8 @@ static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
 		btrfs_exclop_finish(fs_info);
 		btrfs_warn(fs_info,
 	   "cannot activate swapfile because snapshot creation is in progress");
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_unlock_mmap;
 	}
 	/*
 	 * Snapshots can create extents which require COW even if NODATACOW is
@@ -9881,7 +9966,8 @@ static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
 		btrfs_warn(fs_info,
 		"cannot activate swapfile because subvolume %llu is being deleted",
 			btrfs_root_id(root));
-		return -EPERM;
+		ret = -EPERM;
+		goto out_unlock_mmap;
 	}
 	atomic_inc(&root->nr_swapfiles);
 	spin_unlock(&root->root_item_lock);
@@ -9889,24 +9975,39 @@ static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
 	isize = ALIGN_DOWN(inode->i_size, fs_info->sectorsize);
 
 	lock_extent(io_tree, 0, isize - 1, &cached_state);
-	start = 0;
-	while (start < isize) {
-		u64 logical_block_start, physical_block_start;
+	while (prev_extent_end < isize) {
+		struct btrfs_key key;
+		struct extent_buffer *leaf;
+		struct btrfs_file_extent_item *ei;
 		struct btrfs_block_group *bg;
-		u64 len = isize - start;
+		u64 logical_block_start;
+		u64 physical_block_start;
+		u64 extent_gen;
+		u64 disk_bytenr;
+		u64 len;
 
-		em = btrfs_get_extent(BTRFS_I(inode), NULL, start, len);
-		if (IS_ERR(em)) {
-			ret = PTR_ERR(em);
+		key.objectid = btrfs_ino(BTRFS_I(inode));
+		key.type = BTRFS_EXTENT_DATA_KEY;
+		key.offset = prev_extent_end;
+
+		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+		if (ret < 0)
 			goto out;
-		}
 
-		if (em->disk_bytenr == EXTENT_MAP_HOLE) {
+		/*
+		 * If key not found it means we have an implicit hole (NO_HOLES
+		 * is enabled).
+		 */
+		if (ret > 0) {
 			btrfs_warn(fs_info, "swapfile must not have holes");
 			ret = -EINVAL;
 			goto out;
 		}
-		if (em->disk_bytenr == EXTENT_MAP_INLINE) {
+
+		leaf = path->nodes[0];
+		ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item);
+
+		if (btrfs_file_extent_type(leaf, ei) == BTRFS_FILE_EXTENT_INLINE) {
 			/*
 			 * It's unlikely we'll ever actually find ourselves
 			 * here, as a file small enough to fit inline won't be
@@ -9918,23 +10019,45 @@ static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
 			ret = -EINVAL;
 			goto out;
 		}
-		if (extent_map_is_compressed(em)) {
+
+		if (btrfs_file_extent_compression(leaf, ei) != BTRFS_COMPRESS_NONE) {
 			btrfs_warn(fs_info, "swapfile must not be compressed");
 			ret = -EINVAL;
 			goto out;
 		}
 
-		logical_block_start = extent_map_block_start(em) + (start - em->start);
-		len = min(len, em->len - (start - em->start));
-		free_extent_map(em);
-		em = NULL;
+		disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, ei);
+		if (disk_bytenr == 0) {
+			btrfs_warn(fs_info, "swapfile must not have holes");
+			ret = -EINVAL;
+			goto out;
+		}
+
+		logical_block_start = disk_bytenr + btrfs_file_extent_offset(leaf, ei);
+		extent_gen = btrfs_file_extent_generation(leaf, ei);
+		prev_extent_end = btrfs_file_extent_end(path);
+
+		if (prev_extent_end > isize)
+			len = isize - key.offset;
+		else
+			len = btrfs_file_extent_num_bytes(leaf, ei);
+
+		backref_ctx->curr_leaf_bytenr = leaf->start;
 
-		ret = can_nocow_extent(inode, start, &len, NULL, false, true);
+		/*
+		 * Don't need the path anymore, release to avoid deadlocks when
+		 * calling btrfs_is_data_extent_shared() because when joining a
+		 * transaction it can block waiting for the current one's commit
+		 * which in turn may be trying to lock the same leaf to flush
+		 * delayed items for example.
+		 */
+		btrfs_release_path(path);
+
+		ret = btrfs_is_data_extent_shared(BTRFS_I(inode), disk_bytenr,
+						  extent_gen, backref_ctx);
 		if (ret < 0) {
 			goto out;
-		} else if (ret) {
-			ret = 0;
-		} else {
+		} else if (ret > 0) {
 			btrfs_warn(fs_info,
 				   "swapfile must not be copy-on-write");
 			ret = -EINVAL;
@@ -9969,7 +10092,6 @@ static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
 
 		physical_block_start = (map->stripes[0].physical +
 					(logical_block_start - map->start));
-		len = min(len, map->chunk_len - (logical_block_start - map->start));
 		btrfs_free_chunk_map(map);
 		map = NULL;
 
@@ -10010,20 +10132,23 @@ static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
 				if (ret)
 					goto out;
 			}
-			bsi.start = start;
+			bsi.start = key.offset;
 			bsi.block_start = physical_block_start;
 			bsi.block_len = len;
 		}
 
-		start += len;
+		if (fatal_signal_pending(current)) {
+			ret = -EINTR;
+			goto out;
+		}
+
+		cond_resched();
 	}
 
 	if (bsi.block_len)
 		ret = btrfs_add_swap_extent(sis, &bsi);
 
 out:
-	if (!IS_ERR_OR_NULL(em))
-		free_extent_map(em);
 	if (!IS_ERR_OR_NULL(map))
 		btrfs_free_chunk_map(map);
 
@@ -10036,6 +10161,10 @@ out:
 
 	btrfs_exclop_finish(fs_info);
 
+out_unlock_mmap:
+	up_write(&BTRFS_I(inode)->i_mmap_lock);
+	btrfs_free_backref_share_ctx(backref_ctx);
+	btrfs_free_path(path);
 	if (ret)
 		return ret;
 
@@ -10044,7 +10173,6 @@ out:
 	*span = bsi.highest_ppage - bsi.lowest_ppage + 1;
 	sis->max = bsi.nr_pages;
 	sis->pages = bsi.nr_pages - 1;
-	sis->highest_bit = bsi.nr_pages - 1;
 	return bsi.nr_extents;
 }
 #else