Commit 76341cab authored by Jeff Layton's avatar Jeff Layton
Browse files

jbd2: don't clear and reset errors after waiting on writeback 



Resetting this flag is almost certainly racy, and will be problematic
with some coming changes.

Make filemap_fdatawait_keep_errors return int, but not clear the flag(s).
Have jbd2 call it instead of filemap_fdatawait and don't attempt to
re-set the error flag if it fails.

Reviewed-by: default avatarJan Kara <jack@suse.cz>
Reviewed-by: default avatarCarlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: default avatarJeff Layton <jlayton@redhat.com>
parent 87354e5d

fs/jbd2/commit.c

+4 −12
Original line number Diff line number Diff line
@@ -263,18 +263,10 @@ static int journal_finish_inode_data_buffers(journal_t *journal, 
			continue;

		jinode->i_flags |= JI_COMMIT_RUNNING;

		spin_unlock(&journal->j_list_lock);

		err = filemap_fdatawait(jinode->i_vfs_inode->i_mapping);

		if (err) {

			/*

			 * Because AS_EIO is cleared by

			 * filemap_fdatawait_range(), set it again so

			 * that user process can get -EIO from fsync().

			 */

			mapping_set_error(jinode->i_vfs_inode->i_mapping, -EIO);



		err = filemap_fdatawait_keep_errors(

				jinode->i_vfs_inode->i_mapping);

		if (!ret)

			ret = err;

		}

		spin_lock(&journal->j_list_lock);

		jinode->i_flags &= ~JI_COMMIT_RUNNING;

		smp_mb();

include/linux/fs.h

+1 −1
Original line number Diff line number Diff line
@@ -2514,7 +2514,7 @@ extern int write_inode_now(struct inode *, int); 
extern int filemap_fdatawrite(struct address_space *);

extern int filemap_flush(struct address_space *);

extern int filemap_fdatawait(struct address_space *);

extern void filemap_fdatawait_keep_errors(struct address_space *);

extern int filemap_fdatawait_keep_errors(struct address_space *mapping);

extern int filemap_fdatawait_range(struct address_space *, loff_t lstart,

				   loff_t lend);

extern int filemap_write_and_wait(struct address_space *mapping);

mm/filemap.c

+14 −2
Original line number Diff line number Diff line
@@ -309,6 +309,16 @@ int filemap_check_errors(struct address_space *mapping) 
}

EXPORT_SYMBOL(filemap_check_errors);



static int filemap_check_and_keep_errors(struct address_space *mapping)

{

	/* Check for outstanding write errors */

	if (test_bit(AS_EIO, &mapping->flags))

		return -EIO;

	if (test_bit(AS_ENOSPC, &mapping->flags))

		return -ENOSPC;

	return 0;

}



/**

 * __filemap_fdatawrite_range - start writeback on mapping dirty pages in range

 * @mapping:	address space structure to write
@@ -453,15 +463,17 @@ EXPORT_SYMBOL(filemap_fdatawait_range); 
 * call sites are system-wide / filesystem-wide data flushers: e.g. sync(2),

 * fsfreeze(8)

 */

void filemap_fdatawait_keep_errors(struct address_space *mapping)

int filemap_fdatawait_keep_errors(struct address_space *mapping)

{

	loff_t i_size = i_size_read(mapping->host);



	if (i_size == 0)

		return;

		return 0;



	__filemap_fdatawait_range(mapping, 0, i_size - 1);

	return filemap_check_and_keep_errors(mapping);

}

EXPORT_SYMBOL(filemap_fdatawait_keep_errors);



/**

 * filemap_fdatawait - wait for all under-writeback pages to complete

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