Commit 36d116e9 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle)
Browse files

ext4: Use scoped memory APIs in ext4_da_write_begin() 



Instead of setting AOP_FLAG_NOFS, use memalloc_nofs_save() and
memalloc_nofs_restore() to prevent GFP_FS allocations recursing
into the filesystem with a journal already started.

Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 8f50c8b7

fs/ext4/ext4.h

+0 −1
Original line number Diff line number Diff line
@@ -3604,7 +3604,6 @@ ext4_journalled_write_inline_data(struct inode *inode, 
extern int ext4_da_write_inline_data_begin(struct address_space *mapping,

					   struct inode *inode,

					   loff_t pos, unsigned len,

					   unsigned flags,

					   struct page **pagep,

					   void **fsdata);

extern int ext4_try_add_inline_entry(handle_t *handle,

fs/ext4/inline.c

+8 −8
Original line number Diff line number Diff line
@@ -906,7 +906,6 @@ static int ext4_da_convert_inline_data_to_extent(struct address_space *mapping, 
int ext4_da_write_inline_data_begin(struct address_space *mapping,

				    struct inode *inode,

				    loff_t pos, unsigned len,

				    unsigned flags,

				    struct page **pagep,

				    void **fsdata)

{
@@ -915,6 +914,7 @@ int ext4_da_write_inline_data_begin(struct address_space *mapping, 
	struct page *page;

	struct ext4_iloc iloc;

	int retries = 0;

	unsigned int flags;



	ret = ext4_get_inode_loc(inode, &iloc);

	if (ret)
@@ -931,12 +931,6 @@ int ext4_da_write_inline_data_begin(struct address_space *mapping, 
	if (ret && ret != -ENOSPC)

		goto out_journal;



	/*

	 * We cannot recurse into the filesystem as the transaction

	 * is already started.

	 */

	flags |= AOP_FLAG_NOFS;



	if (ret == -ENOSPC) {

		ext4_journal_stop(handle);

		ret = ext4_da_convert_inline_data_to_extent(mapping,
@@ -948,7 +942,13 @@ int ext4_da_write_inline_data_begin(struct address_space *mapping, 
		goto out;

	}



	page = grab_cache_page_write_begin(mapping, 0, flags);

	/*

	 * We cannot recurse into the filesystem as the transaction

	 * is already started.

	 */

	flags = memalloc_nofs_save();

	page = grab_cache_page_write_begin(mapping, 0, 0);

	memalloc_nofs_restore(flags);

	if (!page) {

		ret = -ENOMEM;

		goto out_journal;

fs/ext4/inode.c

+1 −2
Original line number Diff line number Diff line
@@ -2954,8 +2954,7 @@ static int ext4_da_write_begin(struct file *file, struct address_space *mapping, 
	trace_ext4_da_write_begin(inode, pos, len, flags);



	if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {

		ret = ext4_da_write_inline_data_begin(mapping, inode,

						      pos, len, flags,

		ret = ext4_da_write_inline_data_begin(mapping, inode, pos, len,

						      pagep, fsdata);

		if (ret < 0)

			return ret;