dm: clean up clone_bio

Remove the no-longer-used struct bio_set argument from clone_bio and split_bvec.
Use tio->ti in __map_bio() instead of passing in ti.
Factor out some code for setting up cloned bios.
Take target_request_nr as a parameter to alloc_tio().

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

1 files changed, 57 insertions, 45 deletions

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 38486df61f58..4521d72637c2 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -985,12 +985,13 @@ int dm_set_target_max_io_len(struct dm_target *ti, sector_t len)
 }
 EXPORT_SYMBOL_GPL(dm_set_target_max_io_len);
 
-static void __map_bio(struct dm_target *ti, struct dm_target_io *tio)
+static void __map_bio(struct dm_target_io *tio)
 {
         int r;
         sector_t sector;
         struct mapped_device *md;
         struct bio *clone = &tio->clone;
+        struct dm_target *ti = tio->ti;
 
         clone->bi_end_io = clone_endio;
         clone->bi_private = tio;
@@ -1031,32 +1032,54 @@ struct clone_info {
         unsigned short idx;
 };
 
+static void bio_setup_sector(struct bio *bio, sector_t sector, sector_t len)
+{
+        bio->bi_sector = sector;
+        bio->bi_size = to_bytes(len);
+}
+
+static void bio_setup_bv(struct bio *bio, unsigned short idx, unsigned short bv_count)
+{
+        bio->bi_idx = idx;
+        bio->bi_vcnt = idx + bv_count;
+        bio->bi_flags &= ~(1 << BIO_SEG_VALID);
+}
+
+static void clone_bio_integrity(struct bio *bio, struct bio *clone,
+                                unsigned short idx, unsigned len, unsigned offset,
+                                unsigned trim)
+{
+        if (!bio_integrity(bio))
+                return;
+
+        bio_integrity_clone(clone, bio, GFP_NOIO);
+
+        if (trim)
+                bio_integrity_trim(clone, bio_sector_offset(bio, idx, offset), len);
+}
+
 /*
  * Creates a little bio that just does part of a bvec.
  */
 static void split_bvec(struct dm_target_io *tio, struct bio *bio,
                        sector_t sector, unsigned short idx, unsigned int offset,
-                       unsigned int len, struct bio_set *bs)
+                       unsigned int len)
 {
         struct bio *clone = &tio->clone;
         struct bio_vec *bv = bio->bi_io_vec + idx;
 
         *clone->bi_io_vec = *bv;
 
-        clone->bi_sector = sector;
+        bio_setup_sector(clone, sector, len);
+
         clone->bi_bdev = bio->bi_bdev;
         clone->bi_rw = bio->bi_rw;
         clone->bi_vcnt = 1;
-        clone->bi_size = to_bytes(len);
         clone->bi_io_vec->bv_offset = offset;
         clone->bi_io_vec->bv_len = clone->bi_size;
         clone->bi_flags |= 1 << BIO_CLONED;
 
-        if (bio_integrity(bio)) {
-                bio_integrity_clone(clone, bio, GFP_NOIO);
-                bio_integrity_trim(clone,
-                                   bio_sector_offset(bio, idx, offset), len);
-        }
+        clone_bio_integrity(bio, clone, idx, len, offset, 1);
 }
 
 /*
@@ -1064,29 +1087,23 @@ static void split_bvec(struct dm_target_io *tio, struct bio *bio,
  */
 static void clone_bio(struct dm_target_io *tio, struct bio *bio,
                       sector_t sector, unsigned short idx,
-                      unsigned short bv_count, unsigned int len,
-                      struct bio_set *bs)
+                      unsigned short bv_count, unsigned int len)
 {
         struct bio *clone = &tio->clone;
+        unsigned trim = 0;
 
         __bio_clone(clone, bio);
-        clone->bi_sector = sector;
-        clone->bi_idx = idx;
-        clone->bi_vcnt = idx + bv_count;
-        clone->bi_size = to_bytes(len);
-        clone->bi_flags &= ~(1 << BIO_SEG_VALID);
-
-        if (bio_integrity(bio)) {
-                bio_integrity_clone(clone, bio, GFP_NOIO);
-
-                if (idx != bio->bi_idx || clone->bi_size < bio->bi_size)
-                        bio_integrity_trim(clone,
-                                           bio_sector_offset(bio, idx, 0), len);
-        }
+        bio_setup_sector(clone, sector, len);
+        bio_setup_bv(clone, idx, bv_count);
+
+        if (idx != bio->bi_idx || clone->bi_size < bio->bi_size)
+                trim = 1;
+        clone_bio_integrity(bio, clone, idx, len, 0, trim);
 }
 
 static struct dm_target_io *alloc_tio(struct clone_info *ci,
-                                      struct dm_target *ti, int nr_iovecs)
+                                      struct dm_target *ti, int nr_iovecs,
+                                      unsigned target_request_nr)
 {
         struct dm_target_io *tio;
         struct bio *clone;
@@ -1097,7 +1114,7 @@ static struct dm_target_io *alloc_tio(struct clone_info *ci,
         tio->io = ci->io;
         tio->ti = ti;
         memset(&tio->info, 0, sizeof(tio->info));
-        tio->target_request_nr = 0;
+        tio->target_request_nr = target_request_nr;
 
         return tio;
 }
@@ -1105,24 +1122,19 @@ static struct dm_target_io *alloc_tio(struct clone_info *ci,
 static void __issue_target_request(struct clone_info *ci, struct dm_target *ti,
                                    unsigned request_nr, sector_t len)
 {
-        struct dm_target_io *tio = alloc_tio(ci, ti, ci->bio->bi_max_vecs);
+        struct dm_target_io *tio = alloc_tio(ci, ti, ci->bio->bi_max_vecs, request_nr);
         struct bio *clone = &tio->clone;
 
-        tio->target_request_nr = request_nr;
-
         /*
          * Discard requests require the bio's inline iovecs be initialized.
          * ci->bio->bi_max_vecs is BIO_INLINE_VECS anyway, for both flush
          * and discard, so no need for concern about wasted bvec allocations.
          */
-
          __bio_clone(clone, ci->bio);
-        if (len) {
-                clone->bi_sector = ci->sector;
-                clone->bi_size = to_bytes(len);
-        }
+        if (len)
+                bio_setup_sector(clone, ci->sector, len);
 
-        __map_bio(ti, tio);
+        __map_bio(tio);
 }
 
 static void __issue_target_requests(struct clone_info *ci, struct dm_target *ti,
@@ -1154,10 +1166,10 @@ static void __clone_and_map_simple(struct clone_info *ci, struct dm_target *ti)
         struct bio *bio = ci->bio;
         struct dm_target_io *tio;
 
-        tio = alloc_tio(ci, ti, bio->bi_max_vecs);
+        tio = alloc_tio(ci, ti, bio->bi_max_vecs, 0);
         clone_bio(tio, bio, ci->sector, ci->idx, bio->bi_vcnt - ci->idx,
-                  ci->sector_count, ci->md->bs);
-        __map_bio(ti, tio);
+                  ci->sector_count);
+        __map_bio(tio);
         ci->sector_count = 0;
 }
 
@@ -1271,10 +1283,9 @@ static int __clone_and_map(struct clone_info *ci)
                         len += bv_len;
                 }
 
-                tio = alloc_tio(ci, ti, bio->bi_max_vecs);
-                clone_bio(tio, bio, ci->sector, ci->idx, i - ci->idx, len,
-                          ci->md->bs);
-                __map_bio(ti, tio);
+                tio = alloc_tio(ci, ti, bio->bi_max_vecs, 0);
+                clone_bio(tio, bio, ci->sector, ci->idx, i - ci->idx, len);
+                __map_bio(tio);
 
                 ci->sector += len;
                 ci->sector_count -= len;
@@ -1299,11 +1310,11 @@ static int __clone_and_map(struct clone_info *ci)
 
                         len = min(remaining, max);
 
-                        tio = alloc_tio(ci, ti, 1);
+                        tio = alloc_tio(ci, ti, 1, 0);
                         split_bvec(tio, bio, ci->sector, ci->idx,
-                                   bv->bv_offset + offset, len, ci->md->bs);
+                                   bv->bv_offset + offset, len);
 
-                        __map_bio(ti, tio);
+                        __map_bio(tio);
 
                         ci->sector += len;
                         ci->sector_count -= len;
@@ -1341,6 +1352,7 @@ static void __split_and_process_bio(struct mapped_device *md, struct bio *bio)
         ci.idx = bio->bi_idx;
 
         start_io_acct(ci.io);
+
         if (bio->bi_rw & REQ_FLUSH) {
                 ci.bio = &ci.md->flush_bio;
                 ci.sector_count = 0;