static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
struct bio *bio)
{
- struct bio_vec *bv, *bvprv = NULL;
- int cluster, i, high, highprv = 1;
+ struct bio_vec bv, bvprv = { NULL };
+ int cluster, high, highprv = 1;
unsigned int seg_size, nr_phys_segs;
struct bio *fbio, *bbio;
+ struct bvec_iter iter;
if (!bio)
return 0;
+ /*
+ * This should probably be returning 0, but blk_add_request_payload()
+ * (Christoph!!!!)
+ */
+ if (bio->bi_rw & REQ_DISCARD)
+ return 1;
+
+ if (bio->bi_rw & REQ_WRITE_SAME)
+ return 1;
+
fbio = bio;
cluster = blk_queue_cluster(q);
seg_size = 0;
nr_phys_segs = 0;
for_each_bio(bio) {
- bio_for_each_segment(bv, bio, i) {
+ bio_for_each_segment(bv, bio, iter) {
/*
* the trick here is making sure that a high page is
* never considered part of another segment, since that
* might change with the bounce page.
*/
- high = page_to_pfn(bv->bv_page) > queue_bounce_pfn(q);
- if (high || highprv)
- goto new_segment;
- if (cluster) {
- if (seg_size + bv->bv_len
+ high = page_to_pfn(bv.bv_page) > queue_bounce_pfn(q);
+ if (!high && !highprv && cluster) {
+ if (seg_size + bv.bv_len
> queue_max_segment_size(q))
goto new_segment;
- if (!BIOVEC_PHYS_MERGEABLE(bvprv, bv))
+ if (!BIOVEC_PHYS_MERGEABLE(&bvprv, &bv))
goto new_segment;
- if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bv))
+ if (!BIOVEC_SEG_BOUNDARY(q, &bvprv, &bv))
goto new_segment;
- seg_size += bv->bv_len;
+ seg_size += bv.bv_len;
bvprv = bv;
continue;
}
nr_phys_segs++;
bvprv = bv;
- seg_size = bv->bv_len;
+ seg_size = bv.bv_len;
highprv = high;
}
bbio = bio;
static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio,
struct bio *nxt)
{
+ struct bio_vec end_bv = { NULL }, nxt_bv;
+ struct bvec_iter iter;
+
if (!blk_queue_cluster(q))
return 0;
if (!bio_has_data(bio))
return 1;
- if (!BIOVEC_PHYS_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt)))
+ bio_for_each_segment(end_bv, bio, iter)
+ if (end_bv.bv_len == iter.bi_size)
+ break;
+
+ nxt_bv = bio_iovec(nxt);
+
+ if (!BIOVEC_PHYS_MERGEABLE(&end_bv, &nxt_bv))
return 0;
/*
* bio and nxt are contiguous in memory; check if the queue allows
* these two to be merged into one
*/
- if (BIO_SEG_BOUNDARY(q, bio, nxt))
+ if (BIOVEC_SEG_BOUNDARY(q, &end_bv, &nxt_bv))
return 1;
return 0;
}
-static void
+static inline void
__blk_segment_map_sg(struct request_queue *q, struct bio_vec *bvec,
- struct scatterlist *sglist, struct bio_vec **bvprv,
+ struct scatterlist *sglist, struct bio_vec *bvprv,
struct scatterlist **sg, int *nsegs, int *cluster)
{
int nbytes = bvec->bv_len;
- if (*bvprv && *cluster) {
+ if (*sg && *cluster) {
if ((*sg)->length + nbytes > queue_max_segment_size(q))
goto new_segment;
- if (!BIOVEC_PHYS_MERGEABLE(*bvprv, bvec))
+ if (!BIOVEC_PHYS_MERGEABLE(bvprv, bvec))
goto new_segment;
- if (!BIOVEC_SEG_BOUNDARY(q, *bvprv, bvec))
+ if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bvec))
goto new_segment;
(*sg)->length += nbytes;
sg_set_page(*sg, bvec->bv_page, nbytes, bvec->bv_offset);
(*nsegs)++;
}
- *bvprv = bvec;
+ *bvprv = *bvec;
+}
+
+static int __blk_bios_map_sg(struct request_queue *q, struct bio *bio,
+ struct scatterlist *sglist,
+ struct scatterlist **sg)
+{
+ struct bio_vec bvec, bvprv = { NULL };
+ struct bvec_iter iter;
+ int nsegs, cluster;
+
+ nsegs = 0;
+ cluster = blk_queue_cluster(q);
+
+ if (bio->bi_rw & REQ_DISCARD) {
+ /*
+ * This is a hack - drivers should be neither modifying the
+ * biovec, nor relying on bi_vcnt - but because of
+ * blk_add_request_payload(), a discard bio may or may not have
+ * a payload we need to set up here (thank you Christoph) and
+ * bi_vcnt is really the only way of telling if we need to.
+ */
+
+ if (bio->bi_vcnt)
+ goto single_segment;
+
+ return 0;
+ }
+
+ if (bio->bi_rw & REQ_WRITE_SAME) {
+single_segment:
+ *sg = sglist;
+ bvec = bio_iovec(bio);
+ sg_set_page(*sg, bvec.bv_page, bvec.bv_len, bvec.bv_offset);
+ return 1;
+ }
+
+ for_each_bio(bio)
+ bio_for_each_segment(bvec, bio, iter)
+ __blk_segment_map_sg(q, &bvec, sglist, &bvprv, sg,
+ &nsegs, &cluster);
+
+ return nsegs;
}
/*
int blk_rq_map_sg(struct request_queue *q, struct request *rq,
struct scatterlist *sglist)
{
- struct bio_vec *bvec, *bvprv;
- struct req_iterator iter;
- struct scatterlist *sg;
- int nsegs, cluster;
-
- nsegs = 0;
- cluster = blk_queue_cluster(q);
-
- /*
- * for each bio in rq
- */
- bvprv = NULL;
- sg = NULL;
- rq_for_each_segment(bvec, rq, iter) {
- __blk_segment_map_sg(q, bvec, sglist, &bvprv, &sg,
- &nsegs, &cluster);
- } /* segments in rq */
+ struct scatterlist *sg = NULL;
+ int nsegs = 0;
+ if (rq->bio)
+ nsegs = __blk_bios_map_sg(q, rq->bio, sglist, &sg);
if (unlikely(rq->cmd_flags & REQ_COPY_USER) &&
(blk_rq_bytes(rq) & q->dma_pad_mask)) {
int blk_bio_map_sg(struct request_queue *q, struct bio *bio,
struct scatterlist *sglist)
{
- struct bio_vec *bvec, *bvprv;
- struct scatterlist *sg;
- int nsegs, cluster;
- unsigned long i;
-
- nsegs = 0;
- cluster = blk_queue_cluster(q);
-
- bvprv = NULL;
- sg = NULL;
- bio_for_each_segment(bvec, bio, i) {
- __blk_segment_map_sg(q, bvec, sglist, &bvprv, &sg,
- &nsegs, &cluster);
- } /* segments in bio */
+ struct scatterlist *sg = NULL;
+ int nsegs;
+ struct bio *next = bio->bi_next;
+ bio->bi_next = NULL;
+ nsegs = __blk_bios_map_sg(q, bio, sglist, &sg);
+ bio->bi_next = next;
if (sg)
sg_mark_end(sg);
int blk_try_merge(struct request *rq, struct bio *bio)
{
- if (blk_rq_pos(rq) + blk_rq_sectors(rq) == bio->bi_sector)
+ if (blk_rq_pos(rq) + blk_rq_sectors(rq) == bio->bi_iter.bi_sector)
return ELEVATOR_BACK_MERGE;
- else if (blk_rq_pos(rq) - bio_sectors(bio) == bio->bi_sector)
+ else if (blk_rq_pos(rq) - bio_sectors(bio) == bio->bi_iter.bi_sector)
return ELEVATOR_FRONT_MERGE;
return ELEVATOR_NO_MERGE;
}
projects / ~andy / linux / blobdiff