Next patch is going to make generic_make_request() handle arbitrary
sized bios by splitting them if necessary. It makes more sense to call
blk_queue_bounce() first, before the bios have been fragmented.
Also, __blk_recalc_rq_segments() now doesn't have to take into account
potential bouncing - it's already been done.
Signed-off-by: Kent Overstreet <koverstr...@google.com>
Cc: Jens Axboe <ax...@kernel.dk>
Cc: Jiri Kosina <jkos...@suse.cz>
Cc: Asai Thambi S P <asamymuth...@micron.com>
---
block/blk-core.c | 14 +++++++-------
block/blk-merge.c | 15 ++++-----------
drivers/block/mtip32xx/mtip32xx.c | 2 --
drivers/block/pktcdvd.c | 2 --
4 files changed, 11 insertions(+), 22 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index 0704c5c..4d6eb60 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1470,13 +1470,6 @@ void blk_queue_bio(struct request_queue *q, struct bio
*bio)
struct request *req;
unsigned int request_count = 0;
- /*
- * low level driver can indicate that it wants pages above a
- * certain limit bounced to low memory (ie for highmem, or even
- * ISA dma in theory)
- */
- blk_queue_bounce(q, &bio);
-
if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) {
bio_endio(bio, -EIO);
return;
@@ -1828,6 +1821,13 @@ void generic_make_request(struct bio *bio)
do {
struct request_queue *q = bdev_get_queue(bio->bi_bdev);
+ /*
+ * low level driver can indicate that it wants pages above a
+ * certain limit bounced to low memory (ie for highmem, or even
+ * ISA dma in theory)
+ */
+ blk_queue_bounce(q, &bio);
+
q->make_request_fn(q, bio);
bio = bio_list_pop(current->bio_list);
diff --git a/block/blk-merge.c b/block/blk-merge.c
index b53ddac..ba48830 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -13,7 +13,7 @@ static unsigned int __blk_recalc_rq_segments(struct
request_queue *q,
struct bio *bio)
{
struct bio_vec bv, bvprv;
- int cluster, high, highprv = 1;
+ int cluster, prev = 0;
unsigned int seg_size, nr_phys_segs;
struct bio *fbio, *bbio;
struct bvec_iter iter;
@@ -27,15 +27,7 @@ static unsigned int __blk_recalc_rq_segments(struct
request_queue *q,
nr_phys_segs = 0;
for_each_bio(bio) {
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 (prev && cluster) {
if (seg_size + bv.bv_len
> queue_max_segment_size(q))
goto new_segment;
@@ -46,6 +38,7 @@ static unsigned int __blk_recalc_rq_segments(struct
request_queue *q,
seg_size += bv.bv_len;
bvprv = bv;
+ prev = 1;
continue;
}
new_segment:
@@ -55,8 +48,8 @@ new_segment:
nr_phys_segs++;
bvprv = bv;
+ prev = 1;
seg_size = bv.bv_len;
- highprv = high;
}
bbio = bio;
}
diff --git a/drivers/block/mtip32xx/mtip32xx.c
b/drivers/block/mtip32xx/mtip32xx.c
index 9fd1751..089cda3 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -3912,8 +3912,6 @@ static void mtip_make_request(struct request_queue
*queue, struct bio *bio)
sg = mtip_hw_get_scatterlist(dd, &tag, unaligned);
if (likely(sg != NULL)) {
- blk_queue_bounce(queue, &bio);
-
if (unlikely((bio)->bi_vcnt > MTIP_MAX_SG)) {
dev_warn(&dd->pdev->dev,
"Maximum number of SGL entries exceeded\n");
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index a929817..3f6ad2b 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -2486,8 +2486,6 @@ static void pkt_make_request(struct request_queue *q,
struct bio *bio)
goto end_io;
}
- blk_queue_bounce(q, &bio);
-
do {
sector_t zone = ZONE(bio->bi_iter.bi_sector, pd);
sector_t last_zone = ZONE(bio_end_sector(bio) - 1, pd);
--
1.8.3.rc1
--
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