block: Convert bio_copy_data() to bvec_iter

Our fancy new bvec iterator makes code like this much easier to write.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/bio.c b/fs/bio.c
index 07b4b7afa695d5e3cd7e5d375ba38f87e19b5176..f61e59b3881525bff5b5b36953481530e5511386 100644 (file)
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -852,58 +852,48 @@ EXPORT_SYMBOL(bio_alloc_pages);
  */
 void bio_copy_data(struct bio *dst, struct bio *src)
 {
-       struct bio_vec *src_bv, *dst_bv;
-       unsigned src_offset, dst_offset, bytes;
+       struct bvec_iter src_iter, dst_iter;
+       struct bio_vec src_bv, dst_bv;
        void *src_p, *dst_p;
+       unsigned bytes;
 
-       src_bv = __bio_iovec(src);
-       dst_bv = __bio_iovec(dst);
-
-       src_offset = src_bv->bv_offset;
-       dst_offset = dst_bv->bv_offset;
+       src_iter = src->bi_iter;
+       dst_iter = dst->bi_iter;
 
        while (1) {
-               if (src_offset == src_bv->bv_offset + src_bv->bv_len) {
-                       src_bv++;
-                       if (src_bv == bio_iovec_idx(src, src->bi_vcnt)) {
-                               src = src->bi_next;
-                               if (!src)
-                                       break;
-
-                               src_bv = __bio_iovec(src);
-                       }
+               if (!src_iter.bi_size) {
+                       src = src->bi_next;
+                       if (!src)
+                               break;
 
-                       src_offset = src_bv->bv_offset;
+                       src_iter = src->bi_iter;
                }
 
-               if (dst_offset == dst_bv->bv_offset + dst_bv->bv_len) {
-                       dst_bv++;
-                       if (dst_bv == bio_iovec_idx(dst, dst->bi_vcnt)) {
-                               dst = dst->bi_next;
-                               if (!dst)
-                                       break;
-
-                               dst_bv = __bio_iovec(dst);
-                       }
+               if (!dst_iter.bi_size) {
+                       dst = dst->bi_next;
+                       if (!dst)
+                               break;
 
-                       dst_offset = dst_bv->bv_offset;
+                       dst_iter = dst->bi_iter;
                }
 
-               bytes = min(dst_bv->bv_offset + dst_bv->bv_len - dst_offset,
-                           src_bv->bv_offset + src_bv->bv_len - src_offset);
+               src_bv = bio_iter_iovec(src, src_iter);
+               dst_bv = bio_iter_iovec(dst, dst_iter);
+
+               bytes = min(src_bv.bv_len, dst_bv.bv_len);
 
-               src_p = kmap_atomic(src_bv->bv_page);
-               dst_p = kmap_atomic(dst_bv->bv_page);
+               src_p = kmap_atomic(src_bv.bv_page);
+               dst_p = kmap_atomic(dst_bv.bv_page);
 
-               memcpy(dst_p + dst_offset,
-                      src_p + src_offset,
+               memcpy(dst_p + dst_bv.bv_offset,
+                      src_p + src_bv.bv_offset,
                       bytes);
 
                kunmap_atomic(dst_p);
                kunmap_atomic(src_p);
 
-               src_offset += bytes;
-               dst_offset += bytes;
+               bio_advance_iter(src, &src_iter, bytes);
+               bio_advance_iter(dst, &dst_iter, bytes);
        }
 }
 EXPORT_SYMBOL(bio_copy_data);