Using local kmaps slightly reduces the chances to stray writes, and
the bvec interface cleans up the code a little bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20210727055646.118787-16-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
        iter.prot_buf = prot_buf;
 
        __bio_for_each_segment(bv, bio, bviter, *proc_iter) {
-               void *kaddr = kmap_atomic(bv.bv_page);
+               void *kaddr = bvec_kmap_local(&bv);
 
-               iter.data_buf = kaddr + bv.bv_offset;
+               iter.data_buf = kaddr;
                iter.data_size = bv.bv_len;
-
                ret = proc_fn(&iter);
-               if (ret) {
-                       kunmap_atomic(kaddr);
-                       return ret;
-               }
+               kunmap_local(kaddr);
+
+               if (ret)
+                       break;
 
-               kunmap_atomic(kaddr);
        }
        return ret;
 }