}
EXPORT_SYMBOL_GPL(__bio_release_pages);
-static void bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter)
+void bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter)
{
size_t size = iov_iter_count(iter);
bio->bi_end_io = blkdev_bio_end_io_async;
bio->bi_ioprio = iocb->ki_ioprio;
- ret = bio_iov_iter_get_pages(bio, iter);
- if (unlikely(ret)) {
- bio->bi_status = BLK_STS_IOERR;
- bio_endio(bio);
- return ret;
+ if (iov_iter_is_bvec(iter)) {
+ /*
+ * Users don't rely on the iterator being in any particular
+ * state for async I/O returning -EIOCBQUEUED, hence we can
+ * avoid expensive iov_iter_advance(). Bypass
+ * bio_iov_iter_get_pages() and set the bvec directly.
+ */
+ bio_iov_bvec_set(bio, iter);
+ } else {
+ ret = bio_iov_iter_get_pages(bio, iter);
+ if (unlikely(ret)) {
+ bio->bi_status = BLK_STS_IOERR;
+ bio_endio(bio);
+ return ret;
+ }
}
dio->size = bio->bi_iter.bi_size;
void __bio_add_page(struct bio *bio, struct page *page,
unsigned int len, unsigned int off);
int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter);
+void bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter);
void __bio_release_pages(struct bio *bio, bool mark_dirty);
extern void bio_set_pages_dirty(struct bio *bio);
extern void bio_check_pages_dirty(struct bio *bio);