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>

1 files changed, 25 insertions, 35 deletions

diff --git a/fs/bio.c b/fs/bio.c
index 07b4b7afa695..f61e59b38815 100644
--- 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);