block: move bvec iterator into include/linux/bvec.h

bvec iterator helpers should be used to implement by
iterate_bvec():lib/iov_iter.c too, and move them into
one header, so that we can keep bvec iterator header
out of CONFIG_BLOCK. Then we can remove the reinventing
of wheel in iterate_bvec().

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Tested-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

2 files changed, 75 insertions, 50 deletions

diff --git a/include/linux/bio.h b/include/linux/bio.h
index 0bbb2e332410..8e0f677c26d2 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -31,6 +31,7 @@
 
 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
 #include <linux/blk_types.h>
+#include <linux/bvec.h>
 
 #define BIO_DEBUG
 
@@ -47,29 +48,6 @@
 #define bio_prio(bio)                   (bio)->bi_ioprio
 #define bio_set_prio(bio, prio)         ((bio)->bi_ioprio = prio)
 
-/*
- * various member access, note that bio_data should of course not be used
- * on highmem page vectors
- */
-#define __bvec_iter_bvec(bvec, iter)    (&(bvec)[(iter).bi_idx])
-
-#define bvec_iter_page(bvec, iter)                              \
-        (__bvec_iter_bvec((bvec), (iter))->bv_page)
-
-#define bvec_iter_len(bvec, iter)                               \
-        min((iter).bi_size,                                     \
-            __bvec_iter_bvec((bvec), (iter))->bv_len - (iter).bi_bvec_done)
-
-#define bvec_iter_offset(bvec, iter)                            \
-        (__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done)
-
-#define bvec_iter_bvec(bvec, iter)                              \
-((struct bio_vec) {                                             \
-        .bv_page        = bvec_iter_page((bvec), (iter)),       \
-        .bv_len         = bvec_iter_len((bvec), (iter)),        \
-        .bv_offset      = bvec_iter_offset((bvec), (iter)),     \
-})
-
 #define bio_iter_iovec(bio, iter)                               \
         bvec_iter_bvec((bio)->bi_io_vec, (iter))
 
@@ -188,33 +166,6 @@ static inline void *bio_data(struct bio *bio)
 #define bio_for_each_segment_all(bvl, bio, i)                           \
         for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
 
-static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter,
-                                     unsigned bytes)
-{
-        WARN_ONCE(bytes > iter->bi_size,
-                  "Attempted to advance past end of bvec iter\n");
-
-        while (bytes) {
-                unsigned len = min(bytes, bvec_iter_len(bv, *iter));
-
-                bytes -= len;
-                iter->bi_size -= len;
-                iter->bi_bvec_done += len;
-
-                if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
-                        iter->bi_bvec_done = 0;
-                        iter->bi_idx++;
-                }
-        }
-}
-
-#define for_each_bvec(bvl, bio_vec, iter, start)                        \
-        for (iter = (start);                                            \
-             (iter).bi_size &&                                          \
-                ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \
-             bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len))
-
-
 static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
                                     unsigned bytes)
 {
diff --git a/include/linux/bvec.h b/include/linux/bvec.h
new file mode 100644
index 000000000000..29c459da277e
--- /dev/null
+++ b/include/linux/bvec.h
@@ -0,0 +1,74 @@
+/*
+ * bvec iterator
+ *
+ * Copyright (C) 2001 Ming Lei <ming.lei@canonical.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public Licens
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
+ */
+#ifndef __LINUX_BVEC_ITER_H
+#define __LINUX_BVEC_ITER_H
+
+#include <linux/blk_types.h>
+
+/*
+ * various member access, note that bio_data should of course not be used
+ * on highmem page vectors
+ */
+#define __bvec_iter_bvec(bvec, iter)    (&(bvec)[(iter).bi_idx])
+
+#define bvec_iter_page(bvec, iter)                              \
+        (__bvec_iter_bvec((bvec), (iter))->bv_page)
+
+#define bvec_iter_len(bvec, iter)                               \
+        min((iter).bi_size,                                     \
+            __bvec_iter_bvec((bvec), (iter))->bv_len - (iter).bi_bvec_done)
+
+#define bvec_iter_offset(bvec, iter)                            \
+        (__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done)
+
+#define bvec_iter_bvec(bvec, iter)                              \
+((struct bio_vec) {                                             \
+        .bv_page        = bvec_iter_page((bvec), (iter)),       \
+        .bv_len         = bvec_iter_len((bvec), (iter)),        \
+        .bv_offset      = bvec_iter_offset((bvec), (iter)),     \
+})
+
+static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter,
+                                     unsigned bytes)
+{
+        WARN_ONCE(bytes > iter->bi_size,
+                  "Attempted to advance past end of bvec iter\n");
+
+        while (bytes) {
+                unsigned len = min(bytes, bvec_iter_len(bv, *iter));
+
+                bytes -= len;
+                iter->bi_size -= len;
+                iter->bi_bvec_done += len;
+
+                if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
+                        iter->bi_bvec_done = 0;
+                        iter->bi_idx++;
+                }
+        }
+}
+
+#define for_each_bvec(bvl, bio_vec, iter, start)                        \
+        for (iter = (start);                                            \
+             (iter).bi_size &&                                          \
+                ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \
+             bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len))
+
+#endif /* __LINUX_BVEC_ITER_H */