1 files changed, 82 insertions, 33 deletions

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index da1096eb1a40..aafcc785f840 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1536,7 +1536,7 @@ static noinline int check_can_nocow(struct btrfs_inode *inode, loff_t pos,
 	u64 num_bytes;
 	int ret;
 
-	ret = btrfs_start_write_no_snapshoting(root);
+	ret = btrfs_start_write_no_snapshotting(root);
 	if (!ret)
 		return -ENOSPC;
 
@@ -1561,7 +1561,7 @@ static noinline int check_can_nocow(struct btrfs_inode *inode, loff_t pos,
 			NULL, NULL, NULL);
 	if (ret <= 0) {
 		ret = 0;
-		btrfs_end_write_no_snapshoting(root);
+		btrfs_end_write_no_snapshotting(root);
 	} else {
 		*write_bytes = min_t(size_t, *write_bytes ,
 				     num_bytes - pos + lockstart);
@@ -1581,6 +1581,7 @@ static noinline ssize_t __btrfs_buffered_write(struct file *file,
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct page **pages = NULL;
 	struct extent_state *cached_state = NULL;
+	struct extent_changeset *data_reserved = NULL;
 	u64 release_bytes = 0;
 	u64 lockstart;
 	u64 lockend;
@@ -1628,7 +1629,9 @@ static noinline ssize_t __btrfs_buffered_write(struct file *file,
 		reserve_bytes = round_up(write_bytes + sector_offset,
 				fs_info->sectorsize);
 
-		ret = btrfs_check_data_free_space(inode, pos, write_bytes);
+		extent_changeset_release(data_reserved);
+		ret = btrfs_check_data_free_space(inode, &data_reserved, pos,
+						  write_bytes);
 		if (ret < 0) {
 			if ((BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW |
 						      BTRFS_INODE_PREALLOC)) &&
@@ -1657,10 +1660,11 @@ static noinline ssize_t __btrfs_buffered_write(struct file *file,
 				reserve_bytes);
 		if (ret) {
 			if (!only_release_metadata)
-				btrfs_free_reserved_data_space(inode, pos,
-							       write_bytes);
+				btrfs_free_reserved_data_space(inode,
+						data_reserved, pos,
+						write_bytes);
 			else
-				btrfs_end_write_no_snapshoting(root);
+				btrfs_end_write_no_snapshotting(root);
 			break;
 		}
 
@@ -1740,8 +1744,9 @@ again:
 				__pos = round_down(pos,
 						   fs_info->sectorsize) +
 					(dirty_pages << PAGE_SHIFT);
-				btrfs_delalloc_release_space(inode, __pos,
-							     release_bytes);
+				btrfs_delalloc_release_space(inode,
+						data_reserved, __pos,
+						release_bytes);
 			}
 		}
 
@@ -1762,7 +1767,7 @@ again:
 
 		release_bytes = 0;
 		if (only_release_metadata)
-			btrfs_end_write_no_snapshoting(root);
+			btrfs_end_write_no_snapshotting(root);
 
 		if (only_release_metadata && copied > 0) {
 			lockstart = round_down(pos,
@@ -1792,16 +1797,17 @@ again:
 
 	if (release_bytes) {
 		if (only_release_metadata) {
-			btrfs_end_write_no_snapshoting(root);
+			btrfs_end_write_no_snapshotting(root);
 			btrfs_delalloc_release_metadata(BTRFS_I(inode),
 					release_bytes);
 		} else {
-			btrfs_delalloc_release_space(inode,
-						round_down(pos, fs_info->sectorsize),
-						release_bytes);
+			btrfs_delalloc_release_space(inode, data_reserved,
+					round_down(pos, fs_info->sectorsize),
+					release_bytes);
 		}
 	}
 
+	extent_changeset_free(data_reserved);
 	return num_written ? num_written : ret;
 }
 
@@ -1876,17 +1882,40 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb,
 	bool sync = (file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host);
 	ssize_t err;
 	loff_t pos;
-	size_t count;
+	size_t count = iov_iter_count(from);
 	loff_t oldsize;
 	int clean_page = 0;
 
-	inode_lock(inode);
+	if (!(iocb->ki_flags & IOCB_DIRECT) &&
+	    (iocb->ki_flags & IOCB_NOWAIT))
+		return -EOPNOTSUPP;
+
+	if (!inode_trylock(inode)) {
+		if (iocb->ki_flags & IOCB_NOWAIT)
+			return -EAGAIN;
+		inode_lock(inode);
+	}
+
 	err = generic_write_checks(iocb, from);
 	if (err <= 0) {
 		inode_unlock(inode);
 		return err;
 	}
 
+	pos = iocb->ki_pos;
+	if (iocb->ki_flags & IOCB_NOWAIT) {
+		/*
+		 * We will allocate space in case nodatacow is not set,
+		 * so bail
+		 */
+		if (!(BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW |
+					      BTRFS_INODE_PREALLOC)) ||
+		    check_can_nocow(BTRFS_I(inode), pos, &count) <= 0) {
+			inode_unlock(inode);
+			return -EAGAIN;
+		}
+	}
+
 	current->backing_dev_info = inode_to_bdi(inode);
 	err = file_remove_privs(file);
 	if (err) {
@@ -1914,8 +1943,6 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb,
 	 */
 	update_time_for_write(inode);
 
-	pos = iocb->ki_pos;
-	count = iov_iter_count(from);
 	start_pos = round_down(pos, fs_info->sectorsize);
 	oldsize = i_size_read(inode);
 	if (start_pos > oldsize) {
@@ -1967,8 +1994,15 @@ out:
 
 int btrfs_release_file(struct inode *inode, struct file *filp)
 {
-	if (filp->private_data)
+	struct btrfs_file_private *private = filp->private_data;
+
+	if (private && private->trans)
 		btrfs_ioctl_trans_end(filp);
+	if (private && private->filldir_buf)
+		kfree(private->filldir_buf);
+	kfree(private);
+	filp->private_data = NULL;
+
 	/*
 	 * ordered_data_close is set by settattr when we are about to truncate
 	 * a file from a non-zero size to a zero size.  This tries to
@@ -2011,7 +2045,7 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_trans_handle *trans;
 	struct btrfs_log_ctx ctx;
-	int ret = 0;
+	int ret = 0, err;
 	bool full_sync = 0;
 	u64 len;
 
@@ -2030,7 +2064,7 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 	 */
 	ret = start_ordered_ops(inode, start, end);
 	if (ret)
-		return ret;
+		goto out;
 
 	inode_lock(inode);
 	atomic_inc(&root->log_batch);
@@ -2135,10 +2169,10 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 		 * An ordered extent might have started before and completed
 		 * already with io errors, in which case the inode was not
 		 * updated and we end up here. So check the inode's mapping
-		 * flags for any errors that might have happened while doing
-		 * writeback of file data.
+		 * for any errors that might have happened since we last
+		 * checked called fsync.
 		 */
-		ret = filemap_check_errors(inode->i_mapping);
+		ret = filemap_check_wb_err(inode->i_mapping, file->f_wb_err);
 		inode_unlock(inode);
 		goto out;
 	}
@@ -2227,6 +2261,9 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 		ret = btrfs_end_transaction(trans);
 	}
 out:
+	err = file_check_and_advance_wb_err(file);
+	if (!ret)
+		ret = err;
 	return ret > 0 ? -EIO : ret;
 }
 
@@ -2390,10 +2427,13 @@ out:
  */
 static int find_first_non_hole(struct inode *inode, u64 *start, u64 *len)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct extent_map *em;
 	int ret = 0;
 
-	em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, *start, *len, 0);
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, 0,
+			      round_down(*start, fs_info->sectorsize),
+			      round_up(*len, fs_info->sectorsize), 0);
 	if (IS_ERR(em))
 		return PTR_ERR(em);
 
@@ -2769,6 +2809,7 @@ static long btrfs_fallocate(struct file *file, int mode,
 {
 	struct inode *inode = file_inode(file);
 	struct extent_state *cached_state = NULL;
+	struct extent_changeset *data_reserved = NULL;
 	struct falloc_range *range;
 	struct falloc_range *tmp;
 	struct list_head reserve_list;
@@ -2898,8 +2939,8 @@ static long btrfs_fallocate(struct file *file, int mode,
 				free_extent_map(em);
 				break;
 			}
-			ret = btrfs_qgroup_reserve_data(inode, cur_offset,
-					last_byte - cur_offset);
+			ret = btrfs_qgroup_reserve_data(inode, &data_reserved,
+					cur_offset, last_byte - cur_offset);
 			if (ret < 0) {
 				free_extent_map(em);
 				break;
@@ -2910,8 +2951,8 @@ static long btrfs_fallocate(struct file *file, int mode,
 			 * range, free reserved data space first, otherwise
 			 * it'll result in false ENOSPC error.
 			 */
-			btrfs_free_reserved_data_space(inode, cur_offset,
-				last_byte - cur_offset);
+			btrfs_free_reserved_data_space(inode, data_reserved,
+					cur_offset, last_byte - cur_offset);
 		}
 		free_extent_map(em);
 		cur_offset = last_byte;
@@ -2930,8 +2971,9 @@ static long btrfs_fallocate(struct file *file, int mode,
 					range->len, i_blocksize(inode),
 					offset + len, &alloc_hint);
 		else
-			btrfs_free_reserved_data_space(inode, range->start,
-						       range->len);
+			btrfs_free_reserved_data_space(inode,
+					data_reserved, range->start,
+					range->len);
 		list_del(&range->list);
 		kfree(range);
 	}
@@ -2969,8 +3011,9 @@ out:
 	inode_unlock(inode);
 	/* Let go of our reservation. */
 	if (ret != 0)
-		btrfs_free_reserved_data_space(inode, alloc_start,
-				       alloc_end - cur_offset);
+		btrfs_free_reserved_data_space(inode, data_reserved,
+				alloc_start, alloc_end - cur_offset);
+	extent_changeset_free(data_reserved);
 	return ret;
 }
 
@@ -3071,13 +3114,19 @@ out:
 	return offset;
 }
 
+static int btrfs_file_open(struct inode *inode, struct file *filp)
+{
+	filp->f_mode |= FMODE_NOWAIT;
+	return generic_file_open(inode, filp);
+}
+
 const struct file_operations btrfs_file_operations = {
 	.llseek		= btrfs_file_llseek,
 	.read_iter      = generic_file_read_iter,
 	.splice_read	= generic_file_splice_read,
 	.write_iter	= btrfs_file_write_iter,
 	.mmap		= btrfs_file_mmap,
-	.open		= generic_file_open,
+	.open		= btrfs_file_open,
 	.release	= btrfs_release_file,
 	.fsync		= btrfs_sync_file,
 	.fallocate	= btrfs_fallocate,