From: Theodore Ts'o <tytso@mit.edu>
Date: Sun, 5 Sep 2021 03:46:32 +0000 (-0400)
Subject: Merge branch 'delalloc-buffer-write' into dev
X-Git-Tag: accepted/tizen/unified/20230118.172025~6232^2~8
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=11ef08c9eb52a808b8903004cba0733df6902a43;p=platform%2Fkernel%2Flinux-rpi.git

Merge branch 'delalloc-buffer-write' into dev

Fix a bug in how we update i_disksize, and the error path in
inline_data_end.  Finally, drop an unnecessary creation of a journal
handle which was only needed for inline data, which can give us a
large performance gain in delayed allocation writes.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---

11ef08c9eb52a808b8903004cba0733df6902a43
diff --cc fs/ext4/inline.c
index 82bf4ff,d30709d..50a3031
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@@ -733,45 -729,76 +733,83 @@@ convert
  int ext4_write_inline_data_end(struct inode *inode, loff_t pos, unsigned len,
  			       unsigned copied, struct page *page)
  {
- 	int ret, no_expand;
+ 	handle_t *handle = ext4_journal_current_handle();
+ 	int no_expand;
  	void *kaddr;
  	struct ext4_iloc iloc;
+ 	int ret = 0, ret2;
+ 
+ 	if (unlikely(copied < len) && !PageUptodate(page))
+ 		copied = 0;
  
- 	if (unlikely(copied < len)) {
- 		if (!PageUptodate(page)) {
- 			copied = 0;
+ 	if (likely(copied)) {
+ 		ret = ext4_get_inode_loc(inode, &iloc);
+ 		if (ret) {
+ 			unlock_page(page);
+ 			put_page(page);
+ 			ext4_std_error(inode->i_sb, ret);
  			goto out;
  		}
- 	}
+ 		ext4_write_lock_xattr(inode, &no_expand);
+ 		BUG_ON(!ext4_has_inline_data(inode));
  
- 	ret = ext4_get_inode_loc(inode, &iloc);
- 	if (ret) {
- 		ext4_std_error(inode->i_sb, ret);
- 		copied = 0;
- 		goto out;
- 	}
++		/*
++		 * ei->i_inline_off may have changed since
++		 * ext4_write_begin() called
++		 * ext4_try_to_write_inline_data()
++		 */
++		(void) ext4_find_inline_data_nolock(inode);
 +
- 	ext4_write_lock_xattr(inode, &no_expand);
- 	BUG_ON(!ext4_has_inline_data(inode));
+ 		kaddr = kmap_atomic(page);
+ 		ext4_write_inline_data(inode, &iloc, kaddr, pos, copied);
+ 		kunmap_atomic(kaddr);
+ 		SetPageUptodate(page);
+ 		/* clear page dirty so that writepages wouldn't work for us. */
+ 		ClearPageDirty(page);
  
- 	/*
- 	 * ei->i_inline_off may have changed since ext4_write_begin()
- 	 * called ext4_try_to_write_inline_data()
- 	 */
- 	(void) ext4_find_inline_data_nolock(inode);
+ 		ext4_write_unlock_xattr(inode, &no_expand);
+ 		brelse(iloc.bh);
  
- 	kaddr = kmap_atomic(page);
- 	ext4_write_inline_data(inode, &iloc, kaddr, pos, len);
- 	kunmap_atomic(kaddr);
- 	SetPageUptodate(page);
- 	/* clear page dirty so that writepages wouldn't work for us. */
- 	ClearPageDirty(page);
+ 		/*
+ 		 * It's important to update i_size while still holding page
+ 		 * lock: page writeout could otherwise come in and zero
+ 		 * beyond i_size.
+ 		 */
+ 		ext4_update_inode_size(inode, pos + copied);
+ 	}
+ 	unlock_page(page);
+ 	put_page(page);
  
- 	ext4_write_unlock_xattr(inode, &no_expand);
- 	brelse(iloc.bh);
- 	mark_inode_dirty(inode);
+ 	/*
+ 	 * Don't mark the inode dirty under page lock. First, it unnecessarily
+ 	 * makes the holding time of page lock longer. Second, it forces lock
+ 	 * ordering of page lock and transaction start for journaling
+ 	 * filesystems.
+ 	 */
+ 	if (likely(copied))
+ 		mark_inode_dirty(inode);
  out:
- 	return copied;
+ 	/*
+ 	 * If we didn't copy as much data as expected, we need to trim back
+ 	 * size of xattr containing inline data.
+ 	 */
+ 	if (pos + len > inode->i_size && ext4_can_truncate(inode))
+ 		ext4_orphan_add(handle, inode);
+ 
+ 	ret2 = ext4_journal_stop(handle);
+ 	if (!ret)
+ 		ret = ret2;
+ 	if (pos + len > inode->i_size) {
+ 		ext4_truncate_failed_write(inode);
+ 		/*
+ 		 * If truncate failed early the inode might still be
+ 		 * on the orphan list; we need to make sure the inode
+ 		 * is removed from the orphan list in that case.
+ 		 */
+ 		if (inode->i_nlink)
+ 			ext4_orphan_del(NULL, inode);
+ 	}
+ 	return ret ? ret : copied;
  }
  
  struct buffer_head *
diff --cc fs/ext4/inode.c
index 62e9165,502f606..8204176
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@@ -1404,24 -1392,18 +1395,18 @@@ static int ext4_journalled_write_end(st
  
  	BUG_ON(!ext4_handle_valid(handle));
  
- 	if (inline_data) {
- 		ret = ext4_write_inline_data_end(inode, pos, len,
- 						 copied, page);
- 		if (ret < 0) {
- 			unlock_page(page);
- 			put_page(page);
- 			goto errout;
- 		}
- 		copied = ret;
- 	} else if (unlikely(copied < len) && !PageUptodate(page)) {
+ 	if (ext4_has_inline_data(inode))
+ 		return ext4_write_inline_data_end(inode, pos, len, copied, page);
+ 
+ 	if (unlikely(copied < len) && !PageUptodate(page)) {
  		copied = 0;
 -		ext4_journalled_zero_new_buffers(handle, page, from, to);
 +		ext4_journalled_zero_new_buffers(handle, inode, page, from, to);
  	} else {
  		if (unlikely(copied < len))
 -			ext4_journalled_zero_new_buffers(handle, page,
 +			ext4_journalled_zero_new_buffers(handle, inode, page,
  							 from + copied, to);
 -		ret = ext4_walk_page_buffers(handle, page_buffers(page), from,
 -					     from + copied, &partial,
 +		ret = ext4_walk_page_buffers(handle, inode, page_buffers(page),
 +					     from, from + copied, &partial,
  					     write_end_fn);
  		if (!partial)
  			SetPageUptodate(page);