@@ -169,6 +169,16 @@ static int __must_check submit_one_bio(struct bio *bio, int mirror_num,
return blk_status_to_errno(ret);
}
+/* A wrapper for bio_endio() to cleanup unsubmitted bios */
+static void end_write_bio(struct extent_page_data *epd, int ret)
+{
+ if (epd->bio) {
+ epd->bio->bi_status = errno_to_blk_status(ret);
+ bio_endio(epd->bio);
+ epd->bio = NULL;
+ }
+}
+
/*
* A wrapper for submit_one_bio().
*
@@ -3431,6 +3441,9 @@ static noinline_for_stack int __extent_writepage_io(struct inode *inode,
* records are inserted to lock ranges in the tree, and as dirty areas
* are found, they are marked writeback. Then the lock bits are removed
* and the end_io handler clears the writeback ranges
+ *
+ * Return 0 if everything goes well.
+ * Return <0 for error.
*/
static int __extent_writepage(struct page *page, struct writeback_control *wbc,
struct extent_page_data *epd)
@@ -3500,6 +3513,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
end_extent_writepage(page, ret, start, page_end);
}
unlock_page(page);
+ ASSERT(ret <= 0);
return ret;
done_unlocked:
@@ -4040,7 +4054,6 @@ static int extent_write_cache_pages(struct address_space *mapping,
int extent_write_full_page(struct page *page, struct writeback_control *wbc)
{
int ret;
- int flush_ret;
struct extent_page_data epd = {
.bio = NULL,
.tree = &BTRFS_I(page->mapping->host)->io_tree,
@@ -4049,9 +4062,14 @@ int extent_write_full_page(struct page *page, struct writeback_control *wbc)
};
ret = __extent_writepage(page, wbc, &epd);
+ ASSERT(ret <= 0);
+ if (ret < 0) {
+ end_write_bio(&epd, ret);
+ return ret;
+ }
- flush_ret = flush_write_bio(&epd);
- BUG_ON(flush_ret < 0);
+ ret = flush_write_bio(&epd);
+ ASSERT(ret <= 0);
return ret;
}
Since now flush_write_bio() could return error, kill the BUG_ON() first. Then don't call flush_write_bio() unconditionally, instead we check the return value from __extent_writepage() first. If __extent_writepage() fails, we do cleanup, and return error without submitting the possible corrupted or half-baked bio. If __extent_writepage() successes, then we call flush_write_bio() and return the result. Signed-off-by: Qu Wenruo <wqu@suse.com> --- fs/btrfs/extent_io.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-)