bcache: Refactor read request code a bit

More refactoring, and renaming.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index dbc2ef6e7a353c5d0f569f247ec5d8588d14359d..3b85f33ae4c76603fff2014f7b9e94790719a20c 100644 (file)
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -884,7 +884,7 @@ skip:
 
 /* Process reads */
 
-static void cached_dev_read_complete(struct closure *cl)
+static void cached_dev_cache_miss_done(struct closure *cl)
 {
        struct search *s = container_of(cl, struct search, cl);
 
@@ -902,9 +902,10 @@ static void cached_dev_read_complete(struct closure *cl)
        cached_dev_bio_complete(cl);
 }
 
-static void request_read_error(struct closure *cl)
+static void cached_dev_read_error(struct closure *cl)
 {
        struct search *s = container_of(cl, struct search, cl);
+       struct bio *bio = &s->bio.bio;
        struct bio_vec *bv;
        int i;
 
@@ -928,20 +929,20 @@ static void request_read_error(struct closure *cl)
 
                /* XXX: invalidate cache */
 
-               closure_bio_submit(&s->bio.bio, &s->cl, s->d);
+               closure_bio_submit(bio, cl, s->d);
        }
 
-       continue_at(cl, cached_dev_read_complete, NULL);
+       continue_at(cl, cached_dev_cache_miss_done, NULL);
 }
 
-static void request_read_done(struct closure *cl)
+static void cached_dev_read_done(struct closure *cl)
 {
        struct search *s = container_of(cl, struct search, cl);
        struct cached_dev *dc = container_of(s->d, struct cached_dev, disk);
 
        /*
-        * s->cache_bio != NULL implies that we had a cache miss; cache_bio now
-        * contains data ready to be inserted into the cache.
+        * We had a cache miss; cache_bio now contains data ready to be inserted
+        * into the cache.
         *
         * First, we copy the data we just read from cache_bio's bounce buffers
         * to the buffers the original bio pointed to:
@@ -971,10 +972,10 @@ static void request_read_done(struct closure *cl)
                closure_call(&s->op.cl, bch_insert_data, NULL, cl);
        }
 
-       continue_at(cl, cached_dev_read_complete, NULL);
+       continue_at(cl, cached_dev_cache_miss_done, NULL);
 }
 
-static void request_read_done_bh(struct closure *cl)
+static void cached_dev_read_done_bh(struct closure *cl)
 {
        struct search *s = container_of(cl, struct search, cl);
        struct cached_dev *dc = container_of(s->d, struct cached_dev, disk);
@@ -983,11 +984,11 @@ static void request_read_done_bh(struct closure *cl)
        trace_bcache_read(s->orig_bio, !s->cache_miss, s->op.bypass);
 
        if (s->error)
-               continue_at_nobarrier(cl, request_read_error, bcache_wq);
+               continue_at_nobarrier(cl, cached_dev_read_error, bcache_wq);
        else if (s->op.cache_bio || verify(dc, &s->bio.bio))
-               continue_at_nobarrier(cl, request_read_done, bcache_wq);
+               continue_at_nobarrier(cl, cached_dev_read_done, bcache_wq);
        else
-               continue_at_nobarrier(cl, cached_dev_read_complete, NULL);
+               continue_at_nobarrier(cl, cached_dev_bio_complete, NULL);
 }
 
 static int cached_dev_cache_miss(struct btree *b, struct search *s,
@@ -996,7 +997,7 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s,
        int ret = 0;
        unsigned reada = 0;
        struct cached_dev *dc = container_of(s->d, struct cached_dev, disk);
-       struct bio *miss;
+       struct bio *miss, *cache_bio;
 
        if (s->cache_miss || s->op.bypass) {
                miss = bch_bio_split(bio, sectors, GFP_NOIO, s->d->bio_split);
@@ -1027,33 +1028,31 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s,
                /* btree_search_recurse()'s btree iterator is no good anymore */
                ret = -EINTR;
 
-       s->op.cache_bio = bio_alloc_bioset(GFP_NOWAIT,
+       cache_bio = bio_alloc_bioset(GFP_NOWAIT,
                        DIV_ROUND_UP(s->cache_bio_sectors, PAGE_SECTORS),
                        dc->disk.bio_split);
-
-       if (!s->op.cache_bio)
+       if (!cache_bio)
                goto out_submit;
 
-       s->op.cache_bio->bi_sector      = miss->bi_sector;
-       s->op.cache_bio->bi_bdev        = miss->bi_bdev;
-       s->op.cache_bio->bi_size        = s->cache_bio_sectors << 9;
+       cache_bio->bi_sector    = miss->bi_sector;
+       cache_bio->bi_bdev      = miss->bi_bdev;
+       cache_bio->bi_size      = s->cache_bio_sectors << 9;
 
-       s->op.cache_bio->bi_end_io      = request_endio;
-       s->op.cache_bio->bi_private     = &s->cl;
+       cache_bio->bi_end_io    = request_endio;
+       cache_bio->bi_private   = &s->cl;
 
-       bch_bio_map(s->op.cache_bio, NULL);
-       if (bio_alloc_pages(s->op.cache_bio, __GFP_NOWARN|GFP_NOIO))
+       bch_bio_map(cache_bio, NULL);
+       if (bio_alloc_pages(cache_bio, __GFP_NOWARN|GFP_NOIO))
                goto out_put;
 
-       s->cache_miss = miss;
-       bio_get(s->op.cache_bio);
-
-       closure_bio_submit(s->op.cache_bio, &s->cl, s->d);
+       s->cache_miss   = miss;
+       s->op.cache_bio = cache_bio;
+       bio_get(cache_bio);
+       closure_bio_submit(cache_bio, &s->cl, s->d);
 
        return ret;
 out_put:
-       bio_put(s->op.cache_bio);
-       s->op.cache_bio = NULL;
+       bio_put(cache_bio);
 out_submit:
        miss->bi_end_io         = request_endio;
        miss->bi_private        = &s->cl;
@@ -1061,12 +1060,12 @@ out_submit:
        return ret;
 }
 
-static void request_read(struct cached_dev *dc, struct search *s)
+static void cached_dev_read(struct cached_dev *dc, struct search *s)
 {
        struct closure *cl = &s->cl;
 
        closure_call(&s->op.cl, btree_read_async, NULL, cl);
-       continue_at(cl, request_read_done_bh, NULL);
+       continue_at(cl, cached_dev_read_done_bh, NULL);
 }
 
 /* Process writes */
@@ -1080,7 +1079,7 @@ static void cached_dev_write_complete(struct closure *cl)
        cached_dev_bio_complete(cl);
 }
 
-static void request_write(struct cached_dev *dc, struct search *s)
+static void cached_dev_write(struct cached_dev *dc, struct search *s)
 {
        struct closure *cl = &s->cl;
        struct bio *bio = &s->bio.bio;
@@ -1152,7 +1151,7 @@ static void request_write(struct cached_dev *dc, struct search *s)
        continue_at(cl, cached_dev_write_complete, NULL);
 }
 
-static void request_nodata(struct cached_dev *dc, struct search *s)
+static void cached_dev_nodata(struct cached_dev *dc, struct search *s)
 {
        struct closure *cl = &s->cl;
        struct bio *bio = &s->bio.bio;
@@ -1188,14 +1187,14 @@ static void cached_dev_make_request(struct request_queue *q, struct bio *bio)
                trace_bcache_request_start(s, bio);
 
                if (!bio->bi_size)
-                       request_nodata(dc, s);
+                       cached_dev_nodata(dc, s);
                else {
                        s->op.bypass = check_should_bypass(dc, s);
 
                        if (rw)
-                               request_write(dc, s);
+                               cached_dev_write(dc, s);
                        else
-                               request_read(dc, s);
+                               cached_dev_read(dc, s);
                }
        } else {
                if ((bio->bi_rw & REQ_DISCARD) &&