bcache: Use standard utility code

Some of bcache's utility code has made it into the rest of the kernel,
so drop the bcache versions.

Bcache used to have a workaround for allocating from a bio set under
generic_make_request() (if you allocated more than once, the bios you
already allocated would get stuck on current->bio_list when you
submitted, and you'd risk deadlock) - bcache would mask out __GFP_WAIT
when allocating bios under generic_make_request() so that allocation
could fail and it could retry from workqueue. But bio_alloc_bioset() has
a workaround now, so we can drop this hack and the associated error
handling.

Signed-off-by: Kent Overstreet <koverstreet@google.com>

1 files changed, 18 insertions, 69 deletions

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index bcdf1f782c3e..b6e74d3c8faf 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -509,10 +509,6 @@ static void bch_insert_data_loop(struct closure *cl)
                         goto err;
 
                 n = bch_bio_split(bio, KEY_SIZE(k), GFP_NOIO, split);
-                if (!n) {
-                        __bkey_put(op->c, k);
-                        continue_at(cl, bch_insert_data_loop, bcache_wq);
-                }
 
                 n->bi_end_io    = bch_insert_data_endio;
                 n->bi_private   = cl;
@@ -821,53 +817,13 @@ static void request_read_done(struct closure *cl)
          */
 
         if (s->op.cache_bio) {
-                struct bio_vec *src, *dst;
-                unsigned src_offset, dst_offset, bytes;
-                void *dst_ptr;
-
                 bio_reset(s->op.cache_bio);
                 s->op.cache_bio->bi_sector      = s->cache_miss->bi_sector;
                 s->op.cache_bio->bi_bdev        = s->cache_miss->bi_bdev;
                 s->op.cache_bio->bi_size        = s->cache_bio_sectors << 9;
                 bch_bio_map(s->op.cache_bio, NULL);
 
-                src = bio_iovec(s->op.cache_bio);
-                dst = bio_iovec(s->cache_miss);
-                src_offset = src->bv_offset;
-                dst_offset = dst->bv_offset;
-                dst_ptr = kmap(dst->bv_page);
-
-                while (1) {
-                        if (dst_offset == dst->bv_offset + dst->bv_len) {
-                                kunmap(dst->bv_page);
-                                dst++;
-                                if (dst == bio_iovec_idx(s->cache_miss,
-                                                s->cache_miss->bi_vcnt))
-                                        break;
-
-                                dst_offset = dst->bv_offset;
-                                dst_ptr = kmap(dst->bv_page);
-                        }
-
-                        if (src_offset == src->bv_offset + src->bv_len) {
-                                src++;
-                                if (src == bio_iovec_idx(s->op.cache_bio,
-                                                 s->op.cache_bio->bi_vcnt))
-                                        BUG();
-
-                                src_offset = src->bv_offset;
-                        }
-
-                        bytes = min(dst->bv_offset + dst->bv_len - dst_offset,
-                                    src->bv_offset + src->bv_len - src_offset);
-
-                        memcpy(dst_ptr + dst_offset,
-                               page_address(src->bv_page) + src_offset,
-                               bytes);
-
-                        src_offset      += bytes;
-                        dst_offset      += bytes;
-                }
+                bio_copy_data(s->cache_miss, s->op.cache_bio);
 
                 bio_put(s->cache_miss);
                 s->cache_miss = NULL;
@@ -912,9 +868,6 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s,
         struct bio *miss;
 
         miss = bch_bio_split(bio, sectors, GFP_NOIO, s->d->bio_split);
-        if (!miss)
-                return -EAGAIN;
-
         if (miss == bio)
                 s->op.lookup_done = true;
 
@@ -933,8 +886,9 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s,
                 reada = min(dc->readahead >> 9,
                             sectors - bio_sectors(miss));
 
-                if (bio_end(miss) + reada > bdev_sectors(miss->bi_bdev))
-                        reada = bdev_sectors(miss->bi_bdev) - bio_end(miss);
+                if (bio_end_sector(miss) + reada > bdev_sectors(miss->bi_bdev))
+                        reada = bdev_sectors(miss->bi_bdev) -
+                                bio_end_sector(miss);
         }
 
         s->cache_bio_sectors = bio_sectors(miss) + reada;
@@ -958,7 +912,7 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s,
                 goto out_put;
 
         bch_bio_map(s->op.cache_bio, NULL);
-        if (bch_bio_alloc_pages(s->op.cache_bio, __GFP_NOWARN|GFP_NOIO))
+        if (bio_alloc_pages(s->op.cache_bio, __GFP_NOWARN|GFP_NOIO))
                 goto out_put;
 
         s->cache_miss = miss;
@@ -1002,7 +956,7 @@ static void request_write(struct cached_dev *dc, struct search *s)
         struct bio *bio = &s->bio.bio;
         struct bkey start, end;
         start = KEY(dc->disk.id, bio->bi_sector, 0);
-        end = KEY(dc->disk.id, bio_end(bio), 0);
+        end = KEY(dc->disk.id, bio_end_sector(bio), 0);
 
         bch_keybuf_check_overlapping(&s->op.c->moving_gc_keys, &start, &end);
 
@@ -1176,7 +1130,7 @@ found:
                 if (i->sequential + bio->bi_size > i->sequential)
                         i->sequential   += bio->bi_size;
 
-                i->last                  = bio_end(bio);
+                i->last                  = bio_end_sector(bio);
                 i->jiffies               = jiffies + msecs_to_jiffies(5000);
                 s->task->sequential_io   = i->sequential;
 
@@ -1294,30 +1248,25 @@ void bch_cached_dev_request_init(struct cached_dev *dc)
 static int flash_dev_cache_miss(struct btree *b, struct search *s,
                                 struct bio *bio, unsigned sectors)
 {
+        struct bio_vec *bv;
+        int i;
+
         /* Zero fill bio */
 
-        while (bio->bi_idx != bio->bi_vcnt) {
-                struct bio_vec *bv = bio_iovec(bio);
+        bio_for_each_segment(bv, bio, i) {
                 unsigned j = min(bv->bv_len >> 9, sectors);
 
                 void *p = kmap(bv->bv_page);
                 memset(p + bv->bv_offset, 0, j << 9);
                 kunmap(bv->bv_page);
 
-                bv->bv_len      -= j << 9;
-                bv->bv_offset   += j << 9;
-
-                if (bv->bv_len)
-                        return 0;
-
-                bio->bi_sector  += j;
-                bio->bi_size    -= j << 9;
-
-                bio->bi_idx++;
-                sectors         -= j;
+                sectors -= j;
         }
 
-        s->op.lookup_done = true;
+        bio_advance(bio, min(sectors << 9, bio->bi_size));
+
+        if (!bio->bi_size)
+                s->op.lookup_done = true;
 
         return 0;
 }
@@ -1344,8 +1293,8 @@ static void flash_dev_make_request(struct request_queue *q, struct bio *bio)
                 closure_call(&s->op.cl, btree_read_async, NULL, cl);
         } else if (bio_has_data(bio) || s->op.skip) {
                 bch_keybuf_check_overlapping(&s->op.c->moving_gc_keys,
-                                             &KEY(d->id, bio->bi_sector, 0),
-                                             &KEY(d->id, bio_end(bio), 0));
+                                        &KEY(d->id, bio->bi_sector, 0),
+                                        &KEY(d->id, bio_end_sector(bio), 0));
 
                 s->writeback    = true;
                 s->op.cache_bio = bio;