LU-8056 lloop: fix bio_for_each_segment_all for newer kernels

Lustre patch http://review.whamcloud.com/20478 back ported
bio_for_each_segment_all from newer kernels but support
for newer kernels was done incorrectly. Update the code to
work with newer kernels.

Change-Id: I6a926320f80113169a13d2319190721c83d58b1d
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-on: http://review.whamcloud.com/20619
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Wang Shilong <wshilong@ddn.com>
Reviewed-by: Li Dongyang <dongyang.li@anu.edu.au>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/lustre/include/lustre_compat.h b/lustre/include/lustre_compat.h
index d777993..c45dc63 100644 (file)
--- a/lustre/include/lustre_compat.h
+++ b/lustre/include/lustre_compat.h
@@ -411,7 +411,12 @@ static inline void truncate_inode_pages_final(struct address_space *map)
 #endif
 
 #ifndef bio_for_each_segment_all /* since kernel version 3.9 */
+#ifdef HAVE_BVEC_ITER
+#define bio_for_each_segment_all(bv, bio, it) \
+       for (it = 0, bv = (bio)->bi_io_vec; it < (bio)->bi_vcnt; it++, bv++)
+#else
 #define bio_for_each_segment_all(bv, bio, it) bio_for_each_segment(bv, bio, it)
 #endif
+#endif
 
 #endif /* _LUSTRE_COMPAT_H */

diff --git a/lustre/llite/lloop.c b/lustre/llite/lloop.c
index 475185a..be6a112 100644 (file)
--- a/lustre/llite/lloop.c
+++ b/lustre/llite/lloop.c
@@ -193,13 +193,8 @@ static int do_bio_lustrebacked(struct lloop_device *lo, struct bio *head)
         struct cl_object     *obj = ll_i2info(inode)->lli_clob;
         pgoff_t               offset;
         int                   ret;
-#ifdef HAVE_BVEC_ITER
-       struct bvec_iter      iter;
-       struct bio_vec        bvec;
-#else
        int                   iter;
        struct bio_vec       *bvec;
-#endif
         int                   rw;
        size_t                page_count = 0;
         struct bio           *bio;
@@ -226,16 +221,9 @@ static int do_bio_lustrebacked(struct lloop_device *lo, struct bio *head)
 
 #ifdef HAVE_BVEC_ITER
                offset = (pgoff_t)(bio->bi_iter.bi_sector << 9) + lo->lo_offset;
-               bio_for_each_segment_all(bvec, bio, iter) {
-                       BUG_ON(bvec.bv_offset != 0);
-                       BUG_ON(bvec.bv_len != PAGE_CACHE_SIZE);
-
-                       pages[page_count] = bvec.bv_page;
-                       offsets[page_count] = offset;
-                       page_count++;
-                       offset += bvec.bv_len;
 #else
                offset = (pgoff_t)(bio->bi_sector << 9) + lo->lo_offset;
+#endif
                bio_for_each_segment_all(bvec, bio, iter) {
                        BUG_ON(bvec->bv_offset != 0);
                        BUG_ON(bvec->bv_len != PAGE_CACHE_SIZE);
@@ -244,7 +232,6 @@ static int do_bio_lustrebacked(struct lloop_device *lo, struct bio *head)
                        offsets[page_count] = offset;
                        page_count++;
                        offset += bvec->bv_len;
-#endif
                }
                LASSERT(page_count <= LLOOP_MAX_SEGMENTS);
        }