Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "A lot of bug fixes and cleanups for ext4, including:

   - Fix performance problems found in dioread_nolock now that it is the
     default, caused by transaction leaks.

   - Clean up fiemap handling in ext4

   - Clean up and refactor multiple block allocator (mballoc) code

   - Fix a problem with mballoc with a smaller file systems running out
     of blocks because they couldn't properly use blocks that had been
     reserved by inode preallocation.

   - Fixed a race in ext4_sync_parent() versus rename()

   - Simplify the error handling in the extent manipulation code

   - Make sure all metadata I/O errors are felected to
     ext4_ext_dirty()'s and ext4_make_inode_dirty()'s callers.

   - Avoid passing an error pointer to brelse in ext4_xattr_set()

   - Fix race which could result to freeing an inode on the dirty last
     in data=journal mode.

   - Fix refcount handling if ext4_iget() fails

   - Fix a crash in generic/019 caused by a corrupted extent node"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (58 commits)
  ext4: avoid unnecessary transaction starts during writeback
  ext4: don't block for O_DIRECT if IOCB_NOWAIT is set
  ext4: remove the access_ok() check in ext4_ioctl_get_es_cache
  fs: remove the access_ok() check in ioctl_fiemap
  fs: handle FIEMAP_FLAG_SYNC in fiemap_prep
  fs: move fiemap range validation into the file systems instances
  iomap: fix the iomap_fiemap prototype
  fs: move the fiemap definitions out of fs.h
  fs: mark __generic_block_fiemap static
  ext4: remove the call to fiemap_check_flags in ext4_fiemap
  ext4: split _ext4_fiemap
  ext4: fix fiemap size checks for bitmap files
  ext4: fix EXT4_MAX_LOGICAL_BLOCK macro
  add comment for ext4_dir_entry_2 file_type member
  jbd2: avoid leaking transaction credits when unreserving handle
  ext4: drop ext4_journal_free_reserved()
  ext4: mballoc: use lock for checking free blocks while retrying
  ext4: mballoc: refactor ext4_mb_good_group()
  ext4: mballoc: introduce pcpu seqcnt for freeing PA to improve ENOSPC handling
  ext4: mballoc: refactor ext4_mb_discard_preallocations()
  ...

1 files changed, 15 insertions, 2 deletions

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 0d624250a62b..2a01e31a032c 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -287,6 +287,7 @@ static ssize_t ext4_handle_inode_extension(struct inode *inode, loff_t offset,
 	bool truncate = false;
 	u8 blkbits = inode->i_blkbits;
 	ext4_lblk_t written_blk, end_blk;
+	int ret;
 
 	/*
 	 * Note that EXT4_I(inode)->i_disksize can get extended up to
@@ -327,8 +328,14 @@ static ssize_t ext4_handle_inode_extension(struct inode *inode, loff_t offset,
 		goto truncate;
 	}
 
-	if (ext4_update_inode_size(inode, offset + written))
-		ext4_mark_inode_dirty(handle, inode);
+	if (ext4_update_inode_size(inode, offset + written)) {
+		ret = ext4_mark_inode_dirty(handle, inode);
+		if (unlikely(ret)) {
+			written = ret;
+			ext4_journal_stop(handle);
+			goto truncate;
+		}
+	}
 
 	/*
 	 * We may need to truncate allocated but not written blocks beyond EOF.
@@ -495,6 +502,12 @@ static ssize_t ext4_dio_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	if (ret <= 0)
 		return ret;
 
+	/* if we're going to block and IOCB_NOWAIT is set, return -EAGAIN */
+	if ((iocb->ki_flags & IOCB_NOWAIT) && (unaligned_io || extend)) {
+		ret = -EAGAIN;
+		goto out;
+	}
+
 	offset = iocb->ki_pos;
 	count = ret;