bio_map_user_iov(): move alignment check into the main loop
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/block/bio.c b/block/bio.c
index fe40948..d851f68 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1344,11 +1344,6 @@
return ERR_PTR(-EINVAL);
nr_pages += end - start;
- /*
- * buffer must be aligned to at least logical block size for now
- */
- if (uaddr & queue_dma_alignment(q))
- return ERR_PTR(-EINVAL);
}
if (!nr_pages)
@@ -1373,29 +1368,34 @@
npages = DIV_ROUND_UP(offs + bytes, PAGE_SIZE);
- for (j = 0; j < npages; j++) {
- unsigned int n = PAGE_SIZE - offs;
- unsigned short prev_bi_vcnt = bio->bi_vcnt;
+ if (unlikely(offs & queue_dma_alignment(q))) {
+ ret = -EINVAL;
+ j = 0;
+ } else {
+ for (j = 0; j < npages; j++) {
+ struct page *page = pages[j];
+ unsigned int n = PAGE_SIZE - offs;
+ unsigned short prev_bi_vcnt = bio->bi_vcnt;
- if (n > bytes)
- n = bytes;
+ if (n > bytes)
+ n = bytes;
- if (!bio_add_pc_page(q, bio, pages[j], n, offs))
- break;
+ if (!bio_add_pc_page(q, bio, page, n, offs))
+ break;
- /*
- * check if vector was merged with previous
- * drop page reference if needed
- */
- if (bio->bi_vcnt == prev_bi_vcnt)
- put_page(pages[j]);
+ /*
+ * check if vector was merged with previous
+ * drop page reference if needed
+ */
+ if (bio->bi_vcnt == prev_bi_vcnt)
+ put_page(page);
- added += n;
- bytes -= n;
- offs = 0;
+ added += n;
+ bytes -= n;
+ offs = 0;
+ }
+ iov_iter_advance(&i, added);
}
- iov_iter_advance(&i, added);
-
/*
* release the pages we didn't map into the bio, if any
*/