* [PATCH v2 1/9] block: make generic_make_request handle arbitrarily sized bios
2015-01-12 11:49 [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs Dongsu Park
@ 2015-01-12 11:49 ` Dongsu Park
2015-01-12 11:49 ` [PATCH v2 2/9] block: simplify bio_add_page() Dongsu Park
` (8 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: Dongsu Park @ 2015-01-12 11:49 UTC (permalink / raw)
To: linux-kernel
Cc: Christoph Hellwig, Kent Overstreet, Jens Axboe, Ming Lin, Al Viro,
Ming Lei, Neil Brown, Alasdair Kergon, Mike Snitzer, dm-devel,
Lars Ellenberg, drbd-user, Jiri Kosina, Geoff Levand, Jim Paris,
Joshua Morris, Philip Kelleher, Minchan Kim, Nitin Gupta,
Oleg Drokin, Andreas Dilger, Dongsu Park
From: Kent Overstreet <kmo@daterainc.com>
The way the block layer is currently written, it goes to great lengths
to avoid having to split bios; upper layer code (such as bio_add_page())
checks what the underlying device can handle and tries to always create
bios that don't need to be split.
But this approach becomes unwieldy and eventually breaks down with
stacked devices and devices with dynamic limits, and it adds a lot of
complexity. If the block layer could split bios as needed, we could
eliminate a lot of complexity elsewhere - particularly in stacked
drivers. Code that creates bios can then create whatever size bios are
convenient, and more importantly stacked drivers don't have to deal with
both their own bio size limitations and the limitations of the
(potentially multiple) devices underneath them. In the future this will
let us delete merge_bvec_fn and a bunch of other code.
We do this by adding calls to blk_queue_split() to the various
make_request functions that need it - a few can already handle arbitrary
size bios. Note that we add the call _after_ any call to
blk_queue_bounce(); this means that blk_queue_split() and
blk_recalc_rq_segments() don't need to be concerned with bouncing
affecting segment merging.
Some make_request_fn() callbacks were simple enough to audit and verify
they don't need blk_queue_split() calls. The skipped ones are:
* nfhd_make_request (arch/m68k/emu/nfblock.c)
* axon_ram_make_request (arch/powerpc/sysdev/axonram.c)
* simdisk_make_request (arch/xtensa/platforms/iss/simdisk.c)
* brd_make_request (ramdisk - drivers/block/brd.c)
* mtip_submit_request (drivers/block/mtip32xx/mtip32xx.c)
* loop_make_request
* null_queue_bio
* bcache's make_request fns
Some others are almost certainly safe to remove now, but will be left
for future patches.
Cc: Ming Lin <mlin@minggr.net>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: dm-devel@redhat.com
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: drbd-user@lists.linbit.com
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Jim Paris <jim@jtan.com>
Cc: Joshua Morris <josh.h.morris@us.ibm.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
[dpark: skip more mq-based drivers, resolve merge conflicts, etc.]
Signed-off-by: Dongsu Park <dongsu.park@profitbricks.com>
---
block/blk-core.c | 19 ++--
block/blk-merge.c | 151 ++++++++++++++++++++++++++--
block/blk-mq.c | 2 +
drivers/block/drbd/drbd_req.c | 2 +
drivers/block/pktcdvd.c | 6 +-
drivers/block/ps3vram.c | 2 +
drivers/block/rsxx/dev.c | 2 +
drivers/block/umem.c | 2 +
drivers/block/zram/zram_drv.c | 2 +
drivers/md/dm.c | 2 +
drivers/md/md.c | 2 +
drivers/s390/block/dcssblk.c | 2 +
drivers/s390/block/xpram.c | 2 +
drivers/staging/lustre/lustre/llite/lloop.c | 2 +
include/linux/blkdev.h | 3 +
15 files changed, 179 insertions(+), 22 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index 30f6153..e86ad75 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -585,6 +585,10 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
if (q->id < 0)
goto fail_q;
+ q->bio_split = bioset_create(4, 0);
+ if (!q->bio_split)
+ goto fail_id;
+
q->backing_dev_info.ra_pages =
(VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
q->backing_dev_info.state = 0;
@@ -594,7 +598,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
err = bdi_init(&q->backing_dev_info);
if (err)
- goto fail_id;
+ goto fail_split;
setup_timer(&q->backing_dev_info.laptop_mode_wb_timer,
laptop_mode_timer_fn, (unsigned long) q);
@@ -636,6 +640,8 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
fail_bdi:
bdi_destroy(&q->backing_dev_info);
+fail_split:
+ bioset_free(q->bio_split);
fail_id:
ida_simple_remove(&blk_queue_ida, q->id);
fail_q:
@@ -1552,6 +1558,8 @@ void blk_queue_bio(struct request_queue *q, struct bio *bio)
struct request *req;
unsigned int request_count = 0;
+ blk_queue_split(q, &bio, q->bio_split);
+
/*
* low level driver can indicate that it wants pages above a
* certain limit bounced to low memory (ie for highmem, or even
@@ -1775,15 +1783,6 @@ generic_make_request_checks(struct bio *bio)
goto end_io;
}
- if (likely(bio_is_rw(bio) &&
- nr_sectors > queue_max_hw_sectors(q))) {
- printk(KERN_ERR "bio too big device %s (%u > %u)\n",
- bdevname(bio->bi_bdev, b),
- bio_sectors(bio),
- queue_max_hw_sectors(q));
- goto end_io;
- }
-
part = bio->bi_bdev->bd_part;
if (should_fail_request(part, bio->bi_iter.bi_size) ||
should_fail_request(&part_to_disk(part)->part0,
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 89b97b5..3bc2068 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -9,12 +9,150 @@
#include "blk.h"
+static struct bio *blk_bio_discard_split(struct request_queue *q,
+ struct bio *bio,
+ struct bio_set *bs)
+{
+ unsigned int max_discard_sectors, granularity;
+ int alignment;
+ sector_t tmp;
+ unsigned split_sectors;
+
+ /* Zero-sector (unknown) and one-sector granularities are the same. */
+ granularity = max(q->limits.discard_granularity >> 9, 1U);
+
+ max_discard_sectors = min(q->limits.max_discard_sectors, UINT_MAX >> 9);
+ max_discard_sectors -= max_discard_sectors % granularity;
+
+ if (unlikely(!max_discard_sectors)) {
+ /* XXX: warn */
+ return NULL;
+ }
+
+ if (bio_sectors(bio) <= max_discard_sectors)
+ return NULL;
+
+ split_sectors = max_discard_sectors;
+
+ /*
+ * If the next starting sector would be misaligned, stop the discard at
+ * the previous aligned sector.
+ */
+ alignment = (q->limits.discard_alignment >> 9) % granularity;
+
+ tmp = bio->bi_iter.bi_sector + split_sectors - alignment;
+ tmp = sector_div(tmp, granularity);
+
+ if (split_sectors > tmp)
+ split_sectors -= tmp;
+
+ return bio_split(bio, split_sectors, GFP_NOIO, bs);
+}
+
+static struct bio *blk_bio_write_same_split(struct request_queue *q,
+ struct bio *bio,
+ struct bio_set *bs)
+{
+ if (!q->limits.max_write_same_sectors)
+ return NULL;
+
+ if (bio_sectors(bio) <= q->limits.max_write_same_sectors)
+ return NULL;
+
+ return bio_split(bio, q->limits.max_write_same_sectors, GFP_NOIO, bs);
+}
+
+static struct bio *blk_bio_segment_split(struct request_queue *q,
+ struct bio *bio,
+ struct bio_set *bs)
+{
+ struct bio *split;
+ struct bio_vec bv = { 0 }, bvprv = { 0 };
+ struct bvec_iter iter;
+ unsigned seg_size = 0, nsegs = 0;
+ int prev = 0;
+
+ struct bvec_merge_data bvm = {
+ .bi_bdev = bio->bi_bdev,
+ .bi_sector = bio->bi_iter.bi_sector,
+ .bi_size = 0,
+ .bi_rw = bio->bi_rw,
+ };
+
+ bio_for_each_segment(bv, bio, iter) {
+ if (q->merge_bvec_fn &&
+ q->merge_bvec_fn(q, &bvm, &bv) < (int) bv.bv_len)
+ goto split;
+
+ bvm.bi_size += bv.bv_len;
+
+ if (bvm.bi_size >> 9 > queue_max_sectors(q))
+ goto split;
+
+ if (prev && blk_queue_cluster(q)) {
+ if (seg_size + bv.bv_len > queue_max_segment_size(q))
+ goto new_segment;
+ if (!BIOVEC_PHYS_MERGEABLE(&bvprv, &bv))
+ goto new_segment;
+ if (!BIOVEC_SEG_BOUNDARY(q, &bvprv, &bv))
+ goto new_segment;
+
+ seg_size += bv.bv_len;
+ bvprv = bv;
+ prev = 1;
+ continue;
+ }
+new_segment:
+ if (nsegs == queue_max_segments(q))
+ goto split;
+
+ nsegs++;
+ bvprv = bv;
+ prev = 1;
+ seg_size = bv.bv_len;
+ }
+
+ return NULL;
+split:
+ split = bio_clone_bioset(bio, GFP_NOIO, bs);
+
+ split->bi_iter.bi_size -= iter.bi_size;
+ bio->bi_iter = iter;
+
+ if (bio_integrity(bio)) {
+ bio_integrity_advance(bio, split->bi_iter.bi_size);
+ bio_integrity_trim(split, 0, bio_sectors(split));
+ }
+
+ return split;
+}
+
+void blk_queue_split(struct request_queue *q, struct bio **bio,
+ struct bio_set *bs)
+{
+ struct bio *split;
+
+ if ((*bio)->bi_rw & REQ_DISCARD)
+ split = blk_bio_discard_split(q, *bio, bs);
+ else if ((*bio)->bi_rw & REQ_WRITE_SAME)
+ split = blk_bio_write_same_split(q, *bio, bs);
+ else
+ split = blk_bio_segment_split(q, *bio, q->bio_split);
+
+ if (split) {
+ bio_chain(split, *bio);
+ generic_make_request(*bio);
+ *bio = split;
+ }
+}
+EXPORT_SYMBOL(blk_queue_split);
+
static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
struct bio *bio,
bool no_sg_merge)
{
struct bio_vec bv, bvprv = { NULL };
- int cluster, high, highprv = 1;
+ int cluster, prev = 0;
unsigned int seg_size, nr_phys_segs;
struct bio *fbio, *bbio;
struct bvec_iter iter;
@@ -36,7 +174,6 @@ static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
cluster = blk_queue_cluster(q);
seg_size = 0;
nr_phys_segs = 0;
- high = 0;
for_each_bio(bio) {
bio_for_each_segment(bv, bio, iter) {
/*
@@ -46,13 +183,7 @@ static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
if (no_sg_merge)
goto new_segment;
- /*
- * 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 && cluster) {
+ if (prev && cluster) {
if (seg_size + bv.bv_len
> queue_max_segment_size(q))
goto new_segment;
@@ -72,8 +203,8 @@ new_segment:
nr_phys_segs++;
bvprv = bv;
+ prev = 1;
seg_size = bv.bv_len;
- highprv = high;
}
bbio = bio;
}
diff --git a/block/blk-mq.c b/block/blk-mq.c
index da1ab56..20b3ddb 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1259,6 +1259,8 @@ static void blk_sq_make_request(struct request_queue *q, struct bio *bio)
return;
}
+ blk_queue_split(q, &bio, q->bio_split);
+
if (use_plug && !blk_queue_nomerges(q) &&
blk_attempt_plug_merge(q, bio, &request_count))
return;
diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
index 34f2f0b..dee706d 100644
--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -1496,6 +1496,8 @@ void drbd_make_request(struct request_queue *q, struct bio *bio)
struct drbd_device *device = (struct drbd_device *) q->queuedata;
unsigned long start_jif;
+ blk_queue_split(q, &bio, q->bio_split);
+
start_jif = jiffies;
/*
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 09e628da..ea10bd9 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -2446,6 +2446,10 @@ static void pkt_make_request(struct request_queue *q, struct bio *bio)
char b[BDEVNAME_SIZE];
struct bio *split;
+ blk_queue_bounce(q, &bio);
+
+ blk_queue_split(q, &bio, q->bio_split);
+
pd = q->queuedata;
if (!pd) {
pr_err("%s incorrect request queue\n",
@@ -2476,8 +2480,6 @@ static void pkt_make_request(struct request_queue *q, struct bio *bio)
goto end_io;
}
- blk_queue_bounce(q, &bio);
-
do {
sector_t zone = get_zone(bio->bi_iter.bi_sector, pd);
sector_t last_zone = get_zone(bio_end_sector(bio) - 1, pd);
diff --git a/drivers/block/ps3vram.c b/drivers/block/ps3vram.c
index ef45cfb..e32e799 100644
--- a/drivers/block/ps3vram.c
+++ b/drivers/block/ps3vram.c
@@ -605,6 +605,8 @@ static void ps3vram_make_request(struct request_queue *q, struct bio *bio)
dev_dbg(&dev->core, "%s\n", __func__);
+ blk_queue_split(q, &bio, q->bio_split);
+
spin_lock_irq(&priv->lock);
busy = !bio_list_empty(&priv->list);
bio_list_add(&priv->list, bio);
diff --git a/drivers/block/rsxx/dev.c b/drivers/block/rsxx/dev.c
index ac8c62c..50ef199 100644
--- a/drivers/block/rsxx/dev.c
+++ b/drivers/block/rsxx/dev.c
@@ -148,6 +148,8 @@ static void rsxx_make_request(struct request_queue *q, struct bio *bio)
struct rsxx_bio_meta *bio_meta;
int st = -EINVAL;
+ blk_queue_split(q, &bio, q->bio_split);
+
might_sleep();
if (!card)
diff --git a/drivers/block/umem.c b/drivers/block/umem.c
index 4cf81b5..13d577c 100644
--- a/drivers/block/umem.c
+++ b/drivers/block/umem.c
@@ -531,6 +531,8 @@ static void mm_make_request(struct request_queue *q, struct bio *bio)
(unsigned long long)bio->bi_iter.bi_sector,
bio->bi_iter.bi_size);
+ blk_queue_split(q, &bio, q->bio_split);
+
spin_lock_irq(&card->lock);
*card->biotail = bio;
bio->bi_next = NULL;
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index bd8bda3..19526d0 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -909,6 +909,8 @@ static void zram_make_request(struct request_queue *queue, struct bio *bio)
{
struct zram *zram = queue->queuedata;
+ blk_queue_split(queue, &bio, queue->bio_split);
+
down_read(&zram->init_lock);
if (unlikely(!init_done(zram)))
goto error;
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index b98cd9d..fe1e9b7 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1680,6 +1680,8 @@ static void dm_request(struct request_queue *q, struct bio *bio)
{
struct mapped_device *md = q->queuedata;
+ blk_queue_split(q, &bio, q->bio_split);
+
if (dm_request_based(md))
blk_queue_bio(q, bio);
else
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 709755f..48234eb 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -249,6 +249,8 @@ static void md_make_request(struct request_queue *q, struct bio *bio)
struct mddev *mddev = q->queuedata;
unsigned int sectors;
+ blk_queue_split(q, &bio, q->bio_split);
+
if (mddev == NULL || mddev->pers == NULL
|| !mddev->ready) {
bio_io_error(bio);
diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
index b550c8c..658bb7e 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -815,6 +815,8 @@ dcssblk_make_request(struct request_queue *q, struct bio *bio)
unsigned long source_addr;
unsigned long bytes_done;
+ blk_queue_split(q, &bio, q->bio_split);
+
bytes_done = 0;
dev_info = bio->bi_bdev->bd_disk->private_data;
if (dev_info == NULL)
diff --git a/drivers/s390/block/xpram.c b/drivers/s390/block/xpram.c
index 7d4e939..1305ed3 100644
--- a/drivers/s390/block/xpram.c
+++ b/drivers/s390/block/xpram.c
@@ -190,6 +190,8 @@ static void xpram_make_request(struct request_queue *q, struct bio *bio)
unsigned long page_addr;
unsigned long bytes;
+ blk_queue_split(q, &bio, q->bio_split);
+
if ((bio->bi_iter.bi_sector & 7) != 0 ||
(bio->bi_iter.bi_size & 4095) != 0)
/* Request is not page-aligned. */
diff --git a/drivers/staging/lustre/lustre/llite/lloop.c b/drivers/staging/lustre/lustre/llite/lloop.c
index 0312488..fc85916 100644
--- a/drivers/staging/lustre/lustre/llite/lloop.c
+++ b/drivers/staging/lustre/lustre/llite/lloop.c
@@ -341,6 +341,8 @@ static void loop_make_request(struct request_queue *q, struct bio *old_bio)
int rw = bio_rw(old_bio);
int inactive;
+ blk_queue_split(q, &old_bio, q->bio_split);
+
if (!lo)
goto err;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 9621b73..c03e37a 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -484,6 +484,7 @@ struct request_queue {
struct blk_mq_tag_set *tag_set;
struct list_head tag_set_list;
+ struct bio_set *bio_split;
};
#define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
@@ -807,6 +808,8 @@ extern void blk_rq_unprep_clone(struct request *rq);
extern int blk_insert_cloned_request(struct request_queue *q,
struct request *rq);
extern void blk_delay_queue(struct request_queue *, unsigned long);
+extern void blk_queue_split(struct request_queue *, struct bio **,
+ struct bio_set *);
extern void blk_recount_segments(struct request_queue *, struct bio *);
extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
--
2.1.0
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v2 2/9] block: simplify bio_add_page()
2015-01-12 11:49 [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs Dongsu Park
2015-01-12 11:49 ` [PATCH v2 1/9] block: make generic_make_request handle arbitrarily sized bios Dongsu Park
@ 2015-01-12 11:49 ` Dongsu Park
2015-01-12 11:49 ` [PATCH v2 3/9] block: allow __blk_queue_bounce() to handle bios larger than BIO_MAX_PAGES Dongsu Park
` (7 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: Dongsu Park @ 2015-01-12 11:49 UTC (permalink / raw)
To: linux-kernel
Cc: Christoph Hellwig, Kent Overstreet, Jens Axboe, Ming Lin,
Dongsu Park
From: Kent Overstreet <kmo@daterainc.com>
Since generic_make_request() can now handle arbitrary size bios, all we
have to do is make sure the bvec array doesn't overflow.
__bio_add_page() doesn't need to call ->merge_bvec_fn(), where
we can get rid of unnecessary code paths.
Note that removing call to ->merge_bvec_fn() is fine for
bio_add_pc_page(), as SCSI devices usually don't even need that.
Few exceptional cases like pscsi or osd are not affected either.
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ming Lin <mlin@minggr.net>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
[dpark: rebase and resolve merge conflicts, change a couple of comments,
make bio_add_page() warn once upon a cloned bio.]
Signed-off-by: Dongsu Park <dongsu.park@profitbricks.com>
---
block/bio.c | 135 +++++++++++++++++++++++++-----------------------------------
1 file changed, 55 insertions(+), 80 deletions(-)
diff --git a/block/bio.c b/block/bio.c
index 7ff846d..136b78b 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -700,9 +700,23 @@ int bio_get_nr_vecs(struct block_device *bdev)
}
EXPORT_SYMBOL(bio_get_nr_vecs);
-static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
- *page, unsigned int len, unsigned int offset,
- unsigned int max_sectors)
+/**
+ * bio_add_pc_page - attempt to add page to bio
+ * @q: the target queue
+ * @bio: destination bio
+ * @page: page to add
+ * @len: vec entry length
+ * @offset: vec entry offset
+ *
+ * Attempt to add a page to the bio_vec maplist. This can fail for a
+ * number of reasons, such as the bio being full or target block device
+ * limitations. The target block device must allow bio's up to PAGE_SIZE,
+ * so it is always possible to add a single page to an empty bio.
+ *
+ * This should only be used by REQ_PC bios.
+ */
+int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page
+ *page, unsigned int len, unsigned int offset)
{
int retried_segments = 0;
struct bio_vec *bvec;
@@ -713,7 +727,7 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
if (unlikely(bio_flagged(bio, BIO_CLONED)))
return 0;
- if (((bio->bi_iter.bi_size + len) >> 9) > max_sectors)
+ if (((bio->bi_iter.bi_size + len) >> 9) > queue_max_hw_sectors(q))
return 0;
/*
@@ -726,28 +740,7 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
if (page == prev->bv_page &&
offset == prev->bv_offset + prev->bv_len) {
- unsigned int prev_bv_len = prev->bv_len;
prev->bv_len += len;
-
- if (q->merge_bvec_fn) {
- struct bvec_merge_data bvm = {
- /* prev_bvec is already charged in
- bi_size, discharge it in order to
- simulate merging updated prev_bvec
- as new bvec. */
- .bi_bdev = bio->bi_bdev,
- .bi_sector = bio->bi_iter.bi_sector,
- .bi_size = bio->bi_iter.bi_size -
- prev_bv_len,
- .bi_rw = bio->bi_rw,
- };
-
- if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len) {
- prev->bv_len -= len;
- return 0;
- }
- }
-
bio->bi_iter.bi_size += len;
goto done;
}
@@ -790,27 +783,6 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
blk_recount_segments(q, bio);
}
- /*
- * if queue has other restrictions (eg varying max sector size
- * depending on offset), it can specify a merge_bvec_fn in the
- * queue to get further control
- */
- if (q->merge_bvec_fn) {
- struct bvec_merge_data bvm = {
- .bi_bdev = bio->bi_bdev,
- .bi_sector = bio->bi_iter.bi_sector,
- .bi_size = bio->bi_iter.bi_size - len,
- .bi_rw = bio->bi_rw,
- };
-
- /*
- * merge_bvec_fn() returns number of bytes it can accept
- * at this offset
- */
- if (q->merge_bvec_fn(q, &bvm, bvec) < bvec->bv_len)
- goto failed;
- }
-
/* If we may be able to merge these biovecs, force a recount */
if (bio->bi_vcnt > 1 && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec)))
bio->bi_flags &= ~(1 << BIO_SEG_VALID);
@@ -827,28 +799,6 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
blk_recount_segments(q, bio);
return 0;
}
-
-/**
- * bio_add_pc_page - attempt to add page to bio
- * @q: the target queue
- * @bio: destination bio
- * @page: page to add
- * @len: vec entry length
- * @offset: vec entry offset
- *
- * Attempt to add a page to the bio_vec maplist. This can fail for a
- * number of reasons, such as the bio being full or target block device
- * limitations. The target block device must allow bio's up to PAGE_SIZE,
- * so it is always possible to add a single page to an empty bio.
- *
- * This should only be used by REQ_PC bios.
- */
-int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page *page,
- unsigned int len, unsigned int offset)
-{
- return __bio_add_page(q, bio, page, len, offset,
- queue_max_hw_sectors(q));
-}
EXPORT_SYMBOL(bio_add_pc_page);
/**
@@ -858,22 +808,47 @@ EXPORT_SYMBOL(bio_add_pc_page);
* @len: vec entry length
* @offset: vec entry offset
*
- * Attempt to add a page to the bio_vec maplist. This can fail for a
- * number of reasons, such as the bio being full or target block device
- * limitations. The target block device must allow bio's up to PAGE_SIZE,
- * so it is always possible to add a single page to an empty bio.
+ * Attempt to add a page to the bio_vec maplist. This will only fail
+ * if either bio->bi_vcnt == bio->bi_max_vecs or it's a cloned bio.
*/
-int bio_add_page(struct bio *bio, struct page *page, unsigned int len,
- unsigned int offset)
+int bio_add_page(struct bio *bio, struct page *page,
+ unsigned int len, unsigned int offset)
{
- struct request_queue *q = bdev_get_queue(bio->bi_bdev);
- unsigned int max_sectors;
+ struct bio_vec *bv;
- max_sectors = blk_max_size_offset(q, bio->bi_iter.bi_sector);
- if ((max_sectors < (len >> 9)) && !bio->bi_iter.bi_size)
- max_sectors = len >> 9;
+ /*
+ * cloned bio must not modify vec list
+ */
+ if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)))
+ return 0;
- return __bio_add_page(q, bio, page, len, offset, max_sectors);
+ /*
+ * For filesystems with a blocksize smaller than the pagesize
+ * we will often be called with the same page as last time and
+ * a consecutive offset. Optimize this special case.
+ */
+ if (bio->bi_vcnt > 0) {
+ bv = &bio->bi_io_vec[bio->bi_vcnt - 1];
+
+ if (page == bv->bv_page &&
+ offset == bv->bv_offset + bv->bv_len) {
+ bv->bv_len += len;
+ goto done;
+ }
+ }
+
+ if (bio->bi_vcnt >= bio->bi_max_vecs)
+ return 0;
+
+ bv = &bio->bi_io_vec[bio->bi_vcnt];
+ bv->bv_page = page;
+ bv->bv_len = len;
+ bv->bv_offset = offset;
+
+ bio->bi_vcnt++;
+done:
+ bio->bi_iter.bi_size += len;
+ return len;
}
EXPORT_SYMBOL(bio_add_page);
--
2.1.0
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v2 3/9] block: allow __blk_queue_bounce() to handle bios larger than BIO_MAX_PAGES
2015-01-12 11:49 [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs Dongsu Park
2015-01-12 11:49 ` [PATCH v2 1/9] block: make generic_make_request handle arbitrarily sized bios Dongsu Park
2015-01-12 11:49 ` [PATCH v2 2/9] block: simplify bio_add_page() Dongsu Park
@ 2015-01-12 11:49 ` Dongsu Park
2015-01-12 11:49 ` [PATCH v2 4/9] bcache: clean up hacks around bio_split_pool Dongsu Park
` (6 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: Dongsu Park @ 2015-01-12 11:49 UTC (permalink / raw)
To: linux-kernel; +Cc: Christoph Hellwig, Kent Overstreet, Jens Axboe, Dongsu Park
From: Kent Overstreet <kmo@daterainc.com>
Allow __blk_queue_bounce() to handle bios with more than BIO_MAX_PAGES
segments. Doing that, it becomes possible to simplify the block layer
in the kernel.
The issue is that any code that clones the bio and must clone the biovec
(i.e. it can't use bio_clone_fast()) won't be able to allocate a bio with
more than BIO_MAX_PAGES - bio_alloc_bioset() always fails in that case.
Fortunately, it's easy to make __blk_queue_bounce() just process part of
the bio if necessary, using bi_remaining to count the splits and punting
the rest back to generic_make_request().
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
[dpark: add more description in commit message]
Signed-off-by: Dongsu Park <dongsu.park@profitbricks.com>
---
block/bounce.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++--------
1 file changed, 52 insertions(+), 8 deletions(-)
diff --git a/block/bounce.c b/block/bounce.c
index ab21ba2..689ea89 100644
--- a/block/bounce.c
+++ b/block/bounce.c
@@ -196,6 +196,43 @@ static int must_snapshot_stable_pages(struct request_queue *q, struct bio *bio)
}
#endif /* CONFIG_NEED_BOUNCE_POOL */
+static struct bio *bio_clone_segments(struct bio *bio_src, gfp_t gfp_mask,
+ struct bio_set *bs, unsigned nsegs)
+{
+ struct bvec_iter iter;
+ struct bio_vec bv;
+ struct bio *bio;
+
+ bio = bio_alloc_bioset(gfp_mask, nsegs, bs);
+ if (!bio)
+ return NULL;
+
+ bio->bi_bdev = bio_src->bi_bdev;
+ bio->bi_rw = bio_src->bi_rw;
+ bio->bi_iter.bi_sector = bio_src->bi_iter.bi_sector;
+
+ bio_for_each_segment(bv, bio_src, iter) {
+ bio->bi_io_vec[bio->bi_vcnt++] = bv;
+ bio->bi_iter.bi_size += bv.bv_len;
+ if (!--nsegs)
+ break;
+ }
+
+ if (bio_integrity(bio_src)) {
+ int ret;
+
+ ret = bio_integrity_clone(bio, bio_src, gfp_mask);
+ if (ret < 0) {
+ bio_put(bio);
+ return NULL;
+ }
+ }
+
+ bio_src->bi_iter = iter;
+
+ return bio;
+}
+
static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig,
mempool_t *pool, int force)
{
@@ -203,17 +240,24 @@ static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig,
int rw = bio_data_dir(*bio_orig);
struct bio_vec *to, from;
struct bvec_iter iter;
- unsigned i;
+ int i, nsegs = 0, bounce = force;
- if (force)
- goto bounce;
- bio_for_each_segment(from, *bio_orig, iter)
+ bio_for_each_segment(from, *bio_orig, iter) {
+ nsegs++;
if (page_to_pfn(from.bv_page) > queue_bounce_pfn(q))
- goto bounce;
+ bounce = 1;
+ }
+
+ if (!bounce)
+ return;
- return;
-bounce:
- bio = bio_clone_bioset(*bio_orig, GFP_NOIO, fs_bio_set);
+ bio = bio_clone_segments(*bio_orig, GFP_NOIO, fs_bio_set,
+ min(nsegs, BIO_MAX_PAGES));
+
+ if ((*bio_orig)->bi_iter.bi_size) {
+ atomic_inc(&(*bio_orig)->bi_remaining);
+ generic_make_request(*bio_orig);
+ }
bio_for_each_segment_all(to, bio, i) {
struct page *page = to->bv_page;
--
2.1.0
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v2 4/9] bcache: clean up hacks around bio_split_pool
2015-01-12 11:49 [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs Dongsu Park
` (2 preceding siblings ...)
2015-01-12 11:49 ` [PATCH v2 3/9] block: allow __blk_queue_bounce() to handle bios larger than BIO_MAX_PAGES Dongsu Park
@ 2015-01-12 11:49 ` Dongsu Park
2015-01-12 11:49 ` [PATCH v2 5/9] btrfs: remove bio splitting and merge_bvec_fn() calls Dongsu Park
` (5 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: Dongsu Park @ 2015-01-12 11:49 UTC (permalink / raw)
To: linux-kernel
Cc: Christoph Hellwig, Kent Overstreet, Jens Axboe, linux-bcache,
Dongsu Park
From: Kent Overstreet <kmo@daterainc.com>
There has been workarounds only in bcache, for splitting pool as well
as submitting bios. Since generic_make_request() is able to handle
arbitrarily sized bios, it's now possible to delete those hacks.
Cc: linux-bcache@vger.kernel.org
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
[dpark: add more description in commit message]
Signed-off-by: Dongsu Park <dongsu.park@profitbricks.com>
---
drivers/md/bcache/bcache.h | 18 --------
drivers/md/bcache/io.c | 100 +-----------------------------------------
drivers/md/bcache/journal.c | 4 +-
drivers/md/bcache/request.c | 16 +++----
drivers/md/bcache/super.c | 32 +-------------
drivers/md/bcache/util.h | 5 ++-
drivers/md/bcache/writeback.c | 4 +-
7 files changed, 18 insertions(+), 161 deletions(-)
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 04f7bc2..6b420a5 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -243,19 +243,6 @@ struct keybuf {
DECLARE_ARRAY_ALLOCATOR(struct keybuf_key, freelist, KEYBUF_NR);
};
-struct bio_split_pool {
- struct bio_set *bio_split;
- mempool_t *bio_split_hook;
-};
-
-struct bio_split_hook {
- struct closure cl;
- struct bio_split_pool *p;
- struct bio *bio;
- bio_end_io_t *bi_end_io;
- void *bi_private;
-};
-
struct bcache_device {
struct closure cl;
@@ -288,8 +275,6 @@ struct bcache_device {
int (*cache_miss)(struct btree *, struct search *,
struct bio *, unsigned);
int (*ioctl) (struct bcache_device *, fmode_t, unsigned, unsigned long);
-
- struct bio_split_pool bio_split_hook;
};
struct io {
@@ -454,8 +439,6 @@ struct cache {
atomic_long_t meta_sectors_written;
atomic_long_t btree_sectors_written;
atomic_long_t sectors_written;
-
- struct bio_split_pool bio_split_hook;
};
struct gc_stat {
@@ -873,7 +856,6 @@ void bch_bbio_endio(struct cache_set *, struct bio *, int, const char *);
void bch_bbio_free(struct bio *, struct cache_set *);
struct bio *bch_bbio_alloc(struct cache_set *);
-void bch_generic_make_request(struct bio *, struct bio_split_pool *);
void __bch_submit_bbio(struct bio *, struct cache_set *);
void bch_submit_bbio(struct bio *, struct cache_set *, struct bkey *, unsigned);
diff --git a/drivers/md/bcache/io.c b/drivers/md/bcache/io.c
index fa028fa..86a0bb8 100644
--- a/drivers/md/bcache/io.c
+++ b/drivers/md/bcache/io.c
@@ -11,104 +11,6 @@
#include <linux/blkdev.h>
-static unsigned bch_bio_max_sectors(struct bio *bio)
-{
- struct request_queue *q = bdev_get_queue(bio->bi_bdev);
- struct bio_vec bv;
- struct bvec_iter iter;
- unsigned ret = 0, seg = 0;
-
- if (bio->bi_rw & REQ_DISCARD)
- return min(bio_sectors(bio), q->limits.max_discard_sectors);
-
- bio_for_each_segment(bv, bio, iter) {
- struct bvec_merge_data bvm = {
- .bi_bdev = bio->bi_bdev,
- .bi_sector = bio->bi_iter.bi_sector,
- .bi_size = ret << 9,
- .bi_rw = bio->bi_rw,
- };
-
- if (seg == min_t(unsigned, BIO_MAX_PAGES,
- queue_max_segments(q)))
- break;
-
- if (q->merge_bvec_fn &&
- q->merge_bvec_fn(q, &bvm, &bv) < (int) bv.bv_len)
- break;
-
- seg++;
- ret += bv.bv_len >> 9;
- }
-
- ret = min(ret, queue_max_sectors(q));
-
- WARN_ON(!ret);
- ret = max_t(int, ret, bio_iovec(bio).bv_len >> 9);
-
- return ret;
-}
-
-static void bch_bio_submit_split_done(struct closure *cl)
-{
- struct bio_split_hook *s = container_of(cl, struct bio_split_hook, cl);
-
- s->bio->bi_end_io = s->bi_end_io;
- s->bio->bi_private = s->bi_private;
- bio_endio_nodec(s->bio, 0);
-
- closure_debug_destroy(&s->cl);
- mempool_free(s, s->p->bio_split_hook);
-}
-
-static void bch_bio_submit_split_endio(struct bio *bio, int error)
-{
- struct closure *cl = bio->bi_private;
- struct bio_split_hook *s = container_of(cl, struct bio_split_hook, cl);
-
- if (error)
- clear_bit(BIO_UPTODATE, &s->bio->bi_flags);
-
- bio_put(bio);
- closure_put(cl);
-}
-
-void bch_generic_make_request(struct bio *bio, struct bio_split_pool *p)
-{
- struct bio_split_hook *s;
- struct bio *n;
-
- if (!bio_has_data(bio) && !(bio->bi_rw & REQ_DISCARD))
- goto submit;
-
- if (bio_sectors(bio) <= bch_bio_max_sectors(bio))
- goto submit;
-
- s = mempool_alloc(p->bio_split_hook, GFP_NOIO);
- closure_init(&s->cl, NULL);
-
- s->bio = bio;
- s->p = p;
- s->bi_end_io = bio->bi_end_io;
- s->bi_private = bio->bi_private;
- bio_get(bio);
-
- do {
- n = bio_next_split(bio, bch_bio_max_sectors(bio),
- GFP_NOIO, s->p->bio_split);
-
- n->bi_end_io = bch_bio_submit_split_endio;
- n->bi_private = &s->cl;
-
- closure_get(&s->cl);
- generic_make_request(n);
- } while (n != bio);
-
- continue_at(&s->cl, bch_bio_submit_split_done, NULL);
-submit:
- generic_make_request(bio);
-}
-
/* Bios with headers */
void bch_bbio_free(struct bio *bio, struct cache_set *c)
@@ -138,7 +40,7 @@ void __bch_submit_bbio(struct bio *bio, struct cache_set *c)
bio->bi_bdev = PTR_CACHE(c, &b->key, 0)->bdev;
b->submit_time_us = local_clock_us();
- closure_bio_submit(bio, bio->bi_private, PTR_CACHE(c, &b->key, 0));
+ closure_bio_submit(bio, bio->bi_private);
}
void bch_submit_bbio(struct bio *bio, struct cache_set *c,
diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index fe080ad..af47e6c 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -61,7 +61,7 @@ reread: left = ca->sb.bucket_size - offset;
bio->bi_private = &cl;
bch_bio_map(bio, data);
- closure_bio_submit(bio, &cl, ca);
+ closure_bio_submit(bio, &cl);
closure_sync(&cl);
/* This function could be simpler now since we no longer write
@@ -646,7 +646,7 @@ static void journal_write_unlocked(struct closure *cl)
spin_unlock(&c->journal.lock);
while ((bio = bio_list_pop(&list)))
- closure_bio_submit(bio, cl, c->cache[0]);
+ closure_bio_submit(bio, cl);
continue_at(cl, journal_write_done, NULL);
}
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index ab43fad..89500e0 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -710,7 +710,7 @@ static void cached_dev_read_error(struct closure *cl)
/* XXX: invalidate cache */
- closure_bio_submit(bio, cl, s->d);
+ closure_bio_submit(bio, cl);
}
continue_at(cl, cached_dev_cache_miss_done, NULL);
@@ -833,7 +833,7 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s,
s->cache_miss = miss;
s->iop.bio = cache_bio;
bio_get(cache_bio);
- closure_bio_submit(cache_bio, &s->cl, s->d);
+ closure_bio_submit(cache_bio, &s->cl);
return ret;
out_put:
@@ -841,7 +841,7 @@ out_put:
out_submit:
miss->bi_end_io = request_endio;
miss->bi_private = &s->cl;
- closure_bio_submit(miss, &s->cl, s->d);
+ closure_bio_submit(miss, &s->cl);
return ret;
}
@@ -906,7 +906,7 @@ static void cached_dev_write(struct cached_dev *dc, struct search *s)
if (!(bio->bi_rw & REQ_DISCARD) ||
blk_queue_discard(bdev_get_queue(dc->bdev)))
- closure_bio_submit(bio, cl, s->d);
+ closure_bio_submit(bio, cl);
} else if (s->iop.writeback) {
bch_writeback_add(dc);
s->iop.bio = bio;
@@ -921,12 +921,12 @@ static void cached_dev_write(struct cached_dev *dc, struct search *s)
flush->bi_end_io = request_endio;
flush->bi_private = cl;
- closure_bio_submit(flush, cl, s->d);
+ closure_bio_submit(flush, cl);
}
} else {
s->iop.bio = bio_clone_fast(bio, GFP_NOIO, dc->disk.bio_split);
- closure_bio_submit(bio, cl, s->d);
+ closure_bio_submit(bio, cl);
}
closure_call(&s->iop.cl, bch_data_insert, NULL, cl);
@@ -942,7 +942,7 @@ static void cached_dev_nodata(struct closure *cl)
bch_journal_meta(s->iop.c, cl);
/* If it's a flush, we send the flush to the backing device too */
- closure_bio_submit(bio, cl, s->d);
+ closure_bio_submit(bio, cl);
continue_at(cl, cached_dev_bio_complete, NULL);
}
@@ -986,7 +986,7 @@ static void cached_dev_make_request(struct request_queue *q, struct bio *bio)
!blk_queue_discard(bdev_get_queue(dc->bdev)))
bio_endio(bio, 0);
else
- bch_generic_make_request(bio, &d->bio_split_hook);
+ generic_make_request(bio);
}
}
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 4dd2bb7..a542b58 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -59,29 +59,6 @@ struct workqueue_struct *bcache_wq;
#define BTREE_MAX_PAGES (256 * 1024 / PAGE_SIZE)
-static void bio_split_pool_free(struct bio_split_pool *p)
-{
- if (p->bio_split_hook)
- mempool_destroy(p->bio_split_hook);
-
- if (p->bio_split)
- bioset_free(p->bio_split);
-}
-
-static int bio_split_pool_init(struct bio_split_pool *p)
-{
- p->bio_split = bioset_create(4, 0);
- if (!p->bio_split)
- return -ENOMEM;
-
- p->bio_split_hook = mempool_create_kmalloc_pool(4,
- sizeof(struct bio_split_hook));
- if (!p->bio_split_hook)
- return -ENOMEM;
-
- return 0;
-}
-
/* Superblock */
static const char *read_super(struct cache_sb *sb, struct block_device *bdev,
@@ -537,7 +514,7 @@ static void prio_io(struct cache *ca, uint64_t bucket, unsigned long rw)
bio->bi_private = ca;
bch_bio_map(bio, ca->disk_buckets);
- closure_bio_submit(bio, &ca->prio, ca);
+ closure_bio_submit(bio, &ca->prio);
closure_sync(cl);
}
@@ -757,7 +734,6 @@ static void bcache_device_free(struct bcache_device *d)
put_disk(d->disk);
}
- bio_split_pool_free(&d->bio_split_hook);
if (d->bio_split)
bioset_free(d->bio_split);
if (is_vmalloc_addr(d->full_dirty_stripes))
@@ -810,7 +786,6 @@ static int bcache_device_init(struct bcache_device *d, unsigned block_size,
return minor;
if (!(d->bio_split = bioset_create(4, offsetof(struct bbio, bio))) ||
- bio_split_pool_init(&d->bio_split_hook) ||
!(d->disk = alloc_disk(1))) {
ida_simple_remove(&bcache_minor, minor);
return -ENOMEM;
@@ -1799,8 +1774,6 @@ void bch_cache_release(struct kobject *kobj)
ca->set->cache[ca->sb.nr_this_dev] = NULL;
}
- bio_split_pool_free(&ca->bio_split_hook);
-
free_pages((unsigned long) ca->disk_buckets, ilog2(bucket_pages(ca)));
kfree(ca->prio_buckets);
vfree(ca->buckets);
@@ -1845,8 +1818,7 @@ static int cache_alloc(struct cache_sb *sb, struct cache *ca)
ca->sb.nbuckets)) ||
!(ca->prio_buckets = kzalloc(sizeof(uint64_t) * prio_buckets(ca) *
2, GFP_KERNEL)) ||
- !(ca->disk_buckets = alloc_bucket_pages(GFP_KERNEL, ca)) ||
- bio_split_pool_init(&ca->bio_split_hook))
+ !(ca->disk_buckets = alloc_bucket_pages(GFP_KERNEL, ca)))
return -ENOMEM;
ca->prio_last_buckets = ca->prio_buckets + prio_buckets(ca);
diff --git a/drivers/md/bcache/util.h b/drivers/md/bcache/util.h
index 98df757..e3dee05 100644
--- a/drivers/md/bcache/util.h
+++ b/drivers/md/bcache/util.h
@@ -4,6 +4,7 @@
#include <linux/blkdev.h>
#include <linux/errno.h>
+#include <linux/blkdev.h>
#include <linux/kernel.h>
#include <linux/llist.h>
#include <linux/ratelimit.h>
@@ -576,10 +577,10 @@ static inline sector_t bdev_sectors(struct block_device *bdev)
return bdev->bd_inode->i_size >> 9;
}
-#define closure_bio_submit(bio, cl, dev) \
+#define closure_bio_submit(bio, cl) \
do { \
closure_get(cl); \
- bch_generic_make_request(bio, &(dev)->bio_split_hook); \
+ generic_make_request(bio); \
} while (0)
uint64_t bch_crc64_update(uint64_t, const void *, size_t);
diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index f1986bc..ca38362 100644
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -188,7 +188,7 @@ static void write_dirty(struct closure *cl)
io->bio.bi_bdev = io->dc->bdev;
io->bio.bi_end_io = dirty_endio;
- closure_bio_submit(&io->bio, cl, &io->dc->disk);
+ closure_bio_submit(&io->bio, cl);
continue_at(cl, write_dirty_finish, system_wq);
}
@@ -208,7 +208,7 @@ static void read_dirty_submit(struct closure *cl)
{
struct dirty_io *io = container_of(cl, struct dirty_io, cl);
- closure_bio_submit(&io->bio, cl, &io->dc->disk);
+ closure_bio_submit(&io->bio, cl);
continue_at(cl, write_dirty, system_wq);
}
--
2.1.0
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v2 5/9] btrfs: remove bio splitting and merge_bvec_fn() calls
2015-01-12 11:49 [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs Dongsu Park
` (3 preceding siblings ...)
2015-01-12 11:49 ` [PATCH v2 4/9] bcache: clean up hacks around bio_split_pool Dongsu Park
@ 2015-01-12 11:49 ` Dongsu Park
2015-01-12 11:49 ` [PATCH v2 6/9] md/raid5: get rid of bio_fits_rdev() Dongsu Park
` (4 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: Dongsu Park @ 2015-01-12 11:49 UTC (permalink / raw)
To: linux-kernel
Cc: Christoph Hellwig, Kent Overstreet, Jens Axboe, Chris Mason,
Josef Bacik, linux-btrfs, Dongsu Park
From: Kent Overstreet <kmo@daterainc.com>
Btrfs has been doing bio splitting from btrfs_map_bio(), by checking
device limits as well as calling ->merge_bvec_fn() etc. That is not
necessary any more, because generic_make_request() is now able to
handle arbitrarily sized bios. So clean up unnecessary code paths.
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: linux-btrfs@vger.kernel.org
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Chris Mason <clm@fb.com>
[dpark: add more description in commit message]
Signed-off-by: Dongsu Park <dongsu.park@profitbricks.com>
---
fs/btrfs/volumes.c | 73 ------------------------------------------------------
1 file changed, 73 deletions(-)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 50c5a87..c627bf8 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -5691,34 +5691,6 @@ static noinline void btrfs_schedule_bio(struct btrfs_root *root,
&device->work);
}
-static int bio_size_ok(struct block_device *bdev, struct bio *bio,
- sector_t sector)
-{
- struct bio_vec *prev;
- struct request_queue *q = bdev_get_queue(bdev);
- unsigned int max_sectors = queue_max_sectors(q);
- struct bvec_merge_data bvm = {
- .bi_bdev = bdev,
- .bi_sector = sector,
- .bi_rw = bio->bi_rw,
- };
-
- if (WARN_ON(bio->bi_vcnt == 0))
- return 1;
-
- prev = &bio->bi_io_vec[bio->bi_vcnt - 1];
- if (bio_sectors(bio) > max_sectors)
- return 0;
-
- if (!q->merge_bvec_fn)
- return 1;
-
- bvm.bi_size = bio->bi_iter.bi_size - prev->bv_len;
- if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len)
- return 0;
- return 1;
-}
-
static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
struct bio *bio, u64 physical, int dev_nr,
int rw, int async)
@@ -5752,38 +5724,6 @@ static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
btrfsic_submit_bio(rw, bio);
}
-static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
- struct bio *first_bio, struct btrfs_device *dev,
- int dev_nr, int rw, int async)
-{
- struct bio_vec *bvec = first_bio->bi_io_vec;
- struct bio *bio;
- int nr_vecs = bio_get_nr_vecs(dev->bdev);
- u64 physical = bbio->stripes[dev_nr].physical;
-
-again:
- bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS);
- if (!bio)
- return -ENOMEM;
-
- while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) {
- if (bio_add_page(bio, bvec->bv_page, bvec->bv_len,
- bvec->bv_offset) < bvec->bv_len) {
- u64 len = bio->bi_iter.bi_size;
-
- atomic_inc(&bbio->stripes_pending);
- submit_stripe_bio(root, bbio, bio, physical, dev_nr,
- rw, async);
- physical += len;
- goto again;
- }
- bvec++;
- }
-
- submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async);
- return 0;
-}
-
static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
{
atomic_inc(&bbio->error);
@@ -5862,19 +5802,6 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
continue;
}
- /*
- * Check and see if we're ok with this bio based on it's size
- * and offset with the given device.
- */
- if (!bio_size_ok(dev->bdev, first_bio,
- bbio->stripes[dev_nr].physical >> 9)) {
- ret = breakup_stripe_bio(root, bbio, first_bio, dev,
- dev_nr, rw, async_submit);
- BUG_ON(ret);
- dev_nr++;
- continue;
- }
-
if (dev_nr < total_devs - 1) {
bio = btrfs_bio_clone(first_bio, GFP_NOFS);
BUG_ON(!bio); /* -ENOMEM */
--
2.1.0
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v2 6/9] md/raid5: get rid of bio_fits_rdev()
2015-01-12 11:49 [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs Dongsu Park
` (4 preceding siblings ...)
2015-01-12 11:49 ` [PATCH v2 5/9] btrfs: remove bio splitting and merge_bvec_fn() calls Dongsu Park
@ 2015-01-12 11:49 ` Dongsu Park
2015-01-12 11:49 ` [PATCH v2 7/9] block: kill merge_bvec_fn() completely Dongsu Park
` (3 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: Dongsu Park @ 2015-01-12 11:49 UTC (permalink / raw)
To: linux-kernel
Cc: Christoph Hellwig, Kent Overstreet, Jens Axboe, Neil Brown,
linux-raid, Dongsu Park
From: Kent Overstreet <kmo@daterainc.com>
Remove bio_fits_rdev() completely, because ->merge_bvec_fn() has now
gone. There's no point in calling bio_fits_rdev() only for ensuring
aligned read from rdev.
Cc: Neil Brown <neilb@suse.de>
Cc: linux-raid@vger.kernel.org
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
[dpark: add more description in commit message]
Signed-off-by: Dongsu Park <dongsu.park@profitbricks.com>
---
drivers/md/raid5.c | 23 +----------------------
1 file changed, 1 insertion(+), 22 deletions(-)
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index c1b0d52..40e464c 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -4218,25 +4218,6 @@ static void raid5_align_endio(struct bio *bi, int error)
add_bio_to_retry(raid_bi, conf);
}
-static int bio_fits_rdev(struct bio *bi)
-{
- struct request_queue *q = bdev_get_queue(bi->bi_bdev);
-
- if (bio_sectors(bi) > queue_max_sectors(q))
- return 0;
- blk_recount_segments(q, bi);
- if (bi->bi_phys_segments > queue_max_segments(q))
- return 0;
-
- if (q->merge_bvec_fn)
- /* it's too hard to apply the merge_bvec_fn at this stage,
- * just just give up
- */
- return 0;
-
- return 1;
-}
-
static int chunk_aligned_read(struct mddev *mddev, struct bio * raid_bio)
{
struct r5conf *conf = mddev->private;
@@ -4290,11 +4271,9 @@ static int chunk_aligned_read(struct mddev *mddev, struct bio * raid_bio)
align_bi->bi_bdev = rdev->bdev;
__clear_bit(BIO_SEG_VALID, &align_bi->bi_flags);
- if (!bio_fits_rdev(align_bi) ||
- is_badblock(rdev, align_bi->bi_iter.bi_sector,
+ if (is_badblock(rdev, align_bi->bi_iter.bi_sector,
bio_sectors(align_bi),
&first_bad, &bad_sectors)) {
- /* too big in some way, or has a known bad block */
bio_put(align_bi);
rdev_dec_pending(rdev, mddev);
return 0;
--
2.1.0
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v2 7/9] block: kill merge_bvec_fn() completely
2015-01-12 11:49 [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs Dongsu Park
` (5 preceding siblings ...)
2015-01-12 11:49 ` [PATCH v2 6/9] md/raid5: get rid of bio_fits_rdev() Dongsu Park
@ 2015-01-12 11:49 ` Dongsu Park
2015-01-12 11:49 ` [PATCH v2 8/9] fs: use helper bio_add_page() instead of open coding on bi_io_vec Dongsu Park
` (2 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: Dongsu Park @ 2015-01-12 11:49 UTC (permalink / raw)
To: linux-kernel
Cc: Christoph Hellwig, Kent Overstreet, Jens Axboe, Lars Ellenberg,
drbd-user, Jiri Kosina, Yehuda Sadeh, Sage Weil, Alex Elder,
ceph-devel, Alasdair Kergon, Mike Snitzer, dm-devel, Neil Brown,
linux-raid, Martin K. Petersen, Dongsu Park
From: Kent Overstreet <kmo@daterainc.com>
As generic_make_request() is now able to handle arbitrarily sized bios,
it's no longer necessary for each individual block driver to define its
own ->merge_bvec_fn() callback. Remove every invocation completely.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: drbd-user@lists.linbit.com
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@kernel.org>
Cc: ceph-devel@vger.kernel.org
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: dm-devel@redhat.com
Cc: Neil Brown <neilb@suse.de>
Cc: linux-raid@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
[dpark: also remove ->merge_bvec_fn() in dm-thin as well as
dm-era-target, and resolve merge conflicts]
Signed-off-by: Dongsu Park <dongsu.park@profitbricks.com>
---
block/blk-merge.c | 17 +-----
block/blk-settings.c | 22 --------
drivers/block/drbd/drbd_int.h | 1 -
drivers/block/drbd/drbd_main.c | 1 -
drivers/block/drbd/drbd_req.c | 35 ------------
drivers/block/pktcdvd.c | 21 -------
drivers/block/rbd.c | 47 ----------------
drivers/md/dm-cache-target.c | 21 -------
drivers/md/dm-crypt.c | 16 ------
drivers/md/dm-era-target.c | 15 -----
drivers/md/dm-flakey.c | 16 ------
drivers/md/dm-linear.c | 16 ------
drivers/md/dm-snap.c | 15 -----
drivers/md/dm-stripe.c | 21 -------
drivers/md/dm-table.c | 8 ---
drivers/md/dm-thin.c | 31 -----------
drivers/md/dm-verity.c | 16 ------
drivers/md/dm.c | 120 +---------------------------------------
drivers/md/dm.h | 2 -
drivers/md/linear.c | 46 ----------------
drivers/md/md.c | 2 -
drivers/md/md.h | 8 ---
drivers/md/multipath.c | 21 -------
drivers/md/raid0.c | 57 -------------------
drivers/md/raid0.h | 2 -
drivers/md/raid1.c | 59 +-------------------
drivers/md/raid10.c | 122 +----------------------------------------
drivers/md/raid5.c | 28 ----------
include/linux/blkdev.h | 10 ----
include/linux/device-mapper.h | 4 --
30 files changed, 9 insertions(+), 791 deletions(-)
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 3bc2068..8cd7a83 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -69,24 +69,13 @@ static struct bio *blk_bio_segment_split(struct request_queue *q,
struct bio *split;
struct bio_vec bv = { 0 }, bvprv = { 0 };
struct bvec_iter iter;
- unsigned seg_size = 0, nsegs = 0;
+ unsigned seg_size = 0, nsegs = 0, sectors = 0;
int prev = 0;
- struct bvec_merge_data bvm = {
- .bi_bdev = bio->bi_bdev,
- .bi_sector = bio->bi_iter.bi_sector,
- .bi_size = 0,
- .bi_rw = bio->bi_rw,
- };
-
bio_for_each_segment(bv, bio, iter) {
- if (q->merge_bvec_fn &&
- q->merge_bvec_fn(q, &bvm, &bv) < (int) bv.bv_len)
- goto split;
-
- bvm.bi_size += bv.bv_len;
+ sectors += bv.bv_len >> 9;
- if (bvm.bi_size >> 9 > queue_max_sectors(q))
+ if (sectors > queue_max_sectors(q))
goto split;
if (prev && blk_queue_cluster(q)) {
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 6ed2cbe..463a10a 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -53,28 +53,6 @@ void blk_queue_unprep_rq(struct request_queue *q, unprep_rq_fn *ufn)
}
EXPORT_SYMBOL(blk_queue_unprep_rq);
-/**
- * blk_queue_merge_bvec - set a merge_bvec function for queue
- * @q: queue
- * @mbfn: merge_bvec_fn
- *
- * Usually queues have static limitations on the max sectors or segments that
- * we can put in a request. Stacking drivers may have some settings that
- * are dynamic, and thus we have to query the queue whether it is ok to
- * add a new bio_vec to a bio at a given offset or not. If the block device
- * has such limitations, it needs to register a merge_bvec_fn to control
- * the size of bio's sent to it. Note that a block device *must* allow a
- * single page to be added to an empty bio. The block device driver may want
- * to use the bio_split() function to deal with these bio's. By default
- * no merge_bvec_fn is defined for a queue, and only the fixed limits are
- * honored.
- */
-void blk_queue_merge_bvec(struct request_queue *q, merge_bvec_fn *mbfn)
-{
- q->merge_bvec_fn = mbfn;
-}
-EXPORT_SYMBOL(blk_queue_merge_bvec);
-
void blk_queue_softirq_done(struct request_queue *q, softirq_done_fn *fn)
{
q->softirq_done_fn = fn;
diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index b905e98..63ce2b0 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -1449,7 +1449,6 @@ extern void do_submit(struct work_struct *ws);
extern void __drbd_make_request(struct drbd_device *, struct bio *, unsigned long);
extern void drbd_make_request(struct request_queue *q, struct bio *bio);
extern int drbd_read_remote(struct drbd_device *device, struct drbd_request *req);
-extern int drbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bvm, struct bio_vec *bvec);
extern int is_valid_ar_handle(struct drbd_request *, sector_t);
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 1fc8342..f49f53e 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2775,7 +2775,6 @@ enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsig
This triggers a max_bio_size message upon first attach or connect */
blk_queue_max_hw_sectors(q, DRBD_MAX_BIO_SIZE_SAFE >> 8);
blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
- blk_queue_merge_bvec(q, drbd_merge_bvec);
q->queue_lock = &resource->req_lock;
device->md_io.page = alloc_page(GFP_KERNEL);
diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
index dee706d..b57d30b 100644
--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -1509,41 +1509,6 @@ void drbd_make_request(struct request_queue *q, struct bio *bio)
__drbd_make_request(device, bio, start_jif);
}
-/* This is called by bio_add_page().
- *
- * q->max_hw_sectors and other global limits are already enforced there.
- *
- * We need to call down to our lower level device,
- * in case it has special restrictions.
- *
- * We also may need to enforce configured max-bio-bvecs limits.
- *
- * As long as the BIO is empty we have to allow at least one bvec,
- * regardless of size and offset, so no need to ask lower levels.
- */
-int drbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bvm, struct bio_vec *bvec)
-{
- struct drbd_device *device = (struct drbd_device *) q->queuedata;
- unsigned int bio_size = bvm->bi_size;
- int limit = DRBD_MAX_BIO_SIZE;
- int backing_limit;
-
- if (bio_size && get_ldev(device)) {
- unsigned int max_hw_sectors = queue_max_hw_sectors(q);
- struct request_queue * const b =
- device->ldev->backing_bdev->bd_disk->queue;
- if (b->merge_bvec_fn) {
- bvm->bi_bdev = device->ldev->backing_bdev;
- backing_limit = b->merge_bvec_fn(b, bvm, bvec);
- limit = min(limit, backing_limit);
- }
- put_ldev(device);
- if ((limit >> 9) > max_hw_sectors)
- limit = max_hw_sectors << 9;
- }
- return limit;
-}
-
void request_timer_fn(unsigned long data)
{
struct drbd_device *device = (struct drbd_device *) data;
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index ea10bd9..85eac23 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -2505,26 +2505,6 @@ end_io:
-static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
- struct bio_vec *bvec)
-{
- struct pktcdvd_device *pd = q->queuedata;
- sector_t zone = get_zone(bmd->bi_sector, pd);
- int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size;
- int remaining = (pd->settings.size << 9) - used;
- int remaining2;
-
- /*
- * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
- * boundary, pkt_make_request() will split the bio.
- */
- remaining2 = PAGE_SIZE - bmd->bi_size;
- remaining = max(remaining, remaining2);
-
- BUG_ON(remaining < 0);
- return remaining;
-}
-
static void pkt_init_queue(struct pktcdvd_device *pd)
{
struct request_queue *q = pd->disk->queue;
@@ -2532,7 +2512,6 @@ static void pkt_init_queue(struct pktcdvd_device *pd)
blk_queue_make_request(q, pkt_make_request);
blk_queue_logical_block_size(q, CD_FRAMESIZE);
blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
- blk_queue_merge_bvec(q, pkt_merge_bvec);
q->queuedata = pd;
}
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 3ec85df..0c0e2d0 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -3459,52 +3459,6 @@ static void rbd_request_fn(struct request_queue *q)
queue_work(rbd_wq, &rbd_dev->rq_work);
}
-/*
- * a queue callback. Makes sure that we don't create a bio that spans across
- * multiple osd objects. One exception would be with a single page bios,
- * which we handle later at bio_chain_clone_range()
- */
-static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
- struct bio_vec *bvec)
-{
- struct rbd_device *rbd_dev = q->queuedata;
- sector_t sector_offset;
- sector_t sectors_per_obj;
- sector_t obj_sector_offset;
- int ret;
-
- /*
- * Find how far into its rbd object the partition-relative
- * bio start sector is to offset relative to the enclosing
- * device.
- */
- sector_offset = get_start_sect(bmd->bi_bdev) + bmd->bi_sector;
- sectors_per_obj = 1 << (rbd_dev->header.obj_order - SECTOR_SHIFT);
- obj_sector_offset = sector_offset & (sectors_per_obj - 1);
-
- /*
- * Compute the number of bytes from that offset to the end
- * of the object. Account for what's already used by the bio.
- */
- ret = (int) (sectors_per_obj - obj_sector_offset) << SECTOR_SHIFT;
- if (ret > bmd->bi_size)
- ret -= bmd->bi_size;
- else
- ret = 0;
-
- /*
- * Don't send back more than was asked for. And if the bio
- * was empty, let the whole thing through because: "Note
- * that a block device *must* allow a single page to be
- * added to an empty bio."
- */
- rbd_assert(bvec->bv_len <= PAGE_SIZE);
- if (ret > (int) bvec->bv_len || !bmd->bi_size)
- ret = (int) bvec->bv_len;
-
- return ret;
-}
-
static void rbd_free_disk(struct rbd_device *rbd_dev)
{
struct gendisk *disk = rbd_dev->disk;
@@ -3771,7 +3725,6 @@ static int rbd_init_disk(struct rbd_device *rbd_dev)
q->limits.max_discard_sectors = segment_size / SECTOR_SIZE;
q->limits.discard_zeroes_data = 1;
- blk_queue_merge_bvec(q, rbd_merge_bvec);
disk->queue = q;
q->queuedata = rbd_dev;
diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index 1e96d78..72fd9d3 100644
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -3277,26 +3277,6 @@ static int cache_iterate_devices(struct dm_target *ti,
return r;
}
-/*
- * We assume I/O is going to the origin (which is the volume
- * more likely to have restrictions e.g. by being striped).
- * (Looking up the exact location of the data would be expensive
- * and could always be out of date by the time the bio is submitted.)
- */
-static int cache_bvec_merge(struct dm_target *ti,
- struct bvec_merge_data *bvm,
- struct bio_vec *biovec, int max_size)
-{
- struct cache *cache = ti->private;
- struct request_queue *q = bdev_get_queue(cache->origin_dev->bdev);
-
- if (!q->merge_bvec_fn)
- return max_size;
-
- bvm->bi_bdev = cache->origin_dev->bdev;
- return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
-}
-
static void set_discard_limits(struct cache *cache, struct queue_limits *limits)
{
/*
@@ -3340,7 +3320,6 @@ static struct target_type cache_target = {
.status = cache_status,
.message = cache_message,
.iterate_devices = cache_iterate_devices,
- .merge = cache_bvec_merge,
.io_hints = cache_io_hints,
};
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 08981be..723c176 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -1951,21 +1951,6 @@ error:
return -EINVAL;
}
-static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
- struct bio_vec *biovec, int max_size)
-{
- struct crypt_config *cc = ti->private;
- struct request_queue *q = bdev_get_queue(cc->dev->bdev);
-
- if (!q->merge_bvec_fn)
- return max_size;
-
- bvm->bi_bdev = cc->dev->bdev;
- bvm->bi_sector = cc->start + dm_target_offset(ti, bvm->bi_sector);
-
- return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
-}
-
static int crypt_iterate_devices(struct dm_target *ti,
iterate_devices_callout_fn fn, void *data)
{
@@ -1986,7 +1971,6 @@ static struct target_type crypt_target = {
.preresume = crypt_preresume,
.resume = crypt_resume,
.message = crypt_message,
- .merge = crypt_merge,
.iterate_devices = crypt_iterate_devices,
};
diff --git a/drivers/md/dm-era-target.c b/drivers/md/dm-era-target.c
index ad913cd..0119ebf 100644
--- a/drivers/md/dm-era-target.c
+++ b/drivers/md/dm-era-target.c
@@ -1673,20 +1673,6 @@ static int era_iterate_devices(struct dm_target *ti,
return fn(ti, era->origin_dev, 0, get_dev_size(era->origin_dev), data);
}
-static int era_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
- struct bio_vec *biovec, int max_size)
-{
- struct era *era = ti->private;
- struct request_queue *q = bdev_get_queue(era->origin_dev->bdev);
-
- if (!q->merge_bvec_fn)
- return max_size;
-
- bvm->bi_bdev = era->origin_dev->bdev;
-
- return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
-}
-
static void era_io_hints(struct dm_target *ti, struct queue_limits *limits)
{
struct era *era = ti->private;
@@ -1717,7 +1703,6 @@ static struct target_type era_target = {
.status = era_status,
.message = era_message,
.iterate_devices = era_iterate_devices,
- .merge = era_merge,
.io_hints = era_io_hints
};
diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c
index b257e46..d955b3e 100644
--- a/drivers/md/dm-flakey.c
+++ b/drivers/md/dm-flakey.c
@@ -387,21 +387,6 @@ static int flakey_ioctl(struct dm_target *ti, unsigned int cmd, unsigned long ar
return r ? : __blkdev_driver_ioctl(dev->bdev, dev->mode, cmd, arg);
}
-static int flakey_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
- struct bio_vec *biovec, int max_size)
-{
- struct flakey_c *fc = ti->private;
- struct request_queue *q = bdev_get_queue(fc->dev->bdev);
-
- if (!q->merge_bvec_fn)
- return max_size;
-
- bvm->bi_bdev = fc->dev->bdev;
- bvm->bi_sector = flakey_map_sector(ti, bvm->bi_sector);
-
- return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
-}
-
static int flakey_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data)
{
struct flakey_c *fc = ti->private;
@@ -419,7 +404,6 @@ static struct target_type flakey_target = {
.end_io = flakey_end_io,
.status = flakey_status,
.ioctl = flakey_ioctl,
- .merge = flakey_merge,
.iterate_devices = flakey_iterate_devices,
};
diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c
index 53e848c..7dd5fc8 100644
--- a/drivers/md/dm-linear.c
+++ b/drivers/md/dm-linear.c
@@ -130,21 +130,6 @@ static int linear_ioctl(struct dm_target *ti, unsigned int cmd,
return r ? : __blkdev_driver_ioctl(dev->bdev, dev->mode, cmd, arg);
}
-static int linear_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
- struct bio_vec *biovec, int max_size)
-{
- struct linear_c *lc = ti->private;
- struct request_queue *q = bdev_get_queue(lc->dev->bdev);
-
- if (!q->merge_bvec_fn)
- return max_size;
-
- bvm->bi_bdev = lc->dev->bdev;
- bvm->bi_sector = linear_map_sector(ti, bvm->bi_sector);
-
- return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
-}
-
static int linear_iterate_devices(struct dm_target *ti,
iterate_devices_callout_fn fn, void *data)
{
@@ -162,7 +147,6 @@ static struct target_type linear_target = {
.map = linear_map,
.status = linear_status,
.ioctl = linear_ioctl,
- .merge = linear_merge,
.iterate_devices = linear_iterate_devices,
};
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 864b03f..2e6bb7e 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -2234,20 +2234,6 @@ static void origin_status(struct dm_target *ti, status_type_t type,
}
}
-static int origin_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
- struct bio_vec *biovec, int max_size)
-{
- struct dm_origin *o = ti->private;
- struct request_queue *q = bdev_get_queue(o->dev->bdev);
-
- if (!q->merge_bvec_fn)
- return max_size;
-
- bvm->bi_bdev = o->dev->bdev;
-
- return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
-}
-
static int origin_iterate_devices(struct dm_target *ti,
iterate_devices_callout_fn fn, void *data)
{
@@ -2265,7 +2251,6 @@ static struct target_type origin_target = {
.map = origin_map,
.resume = origin_resume,
.status = origin_status,
- .merge = origin_merge,
.iterate_devices = origin_iterate_devices,
};
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index f8b37d4..09bb2fe 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -412,26 +412,6 @@ static void stripe_io_hints(struct dm_target *ti,
blk_limits_io_opt(limits, chunk_size * sc->stripes);
}
-static int stripe_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
- struct bio_vec *biovec, int max_size)
-{
- struct stripe_c *sc = ti->private;
- sector_t bvm_sector = bvm->bi_sector;
- uint32_t stripe;
- struct request_queue *q;
-
- stripe_map_sector(sc, bvm_sector, &stripe, &bvm_sector);
-
- q = bdev_get_queue(sc->stripe[stripe].dev->bdev);
- if (!q->merge_bvec_fn)
- return max_size;
-
- bvm->bi_bdev = sc->stripe[stripe].dev->bdev;
- bvm->bi_sector = sc->stripe[stripe].physical_start + bvm_sector;
-
- return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
-}
-
static struct target_type stripe_target = {
.name = "striped",
.version = {1, 5, 1},
@@ -443,7 +423,6 @@ static struct target_type stripe_target = {
.status = stripe_status,
.iterate_devices = stripe_iterate_devices,
.io_hints = stripe_io_hints,
- .merge = stripe_merge,
};
int __init dm_stripe_init(void)
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 3afae9e..6c14cb4 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -443,14 +443,6 @@ static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
q->limits.alignment_offset,
(unsigned long long) start << SECTOR_SHIFT);
- /*
- * Check if merge fn is supported.
- * If not we'll force DM to use PAGE_SIZE or
- * smaller I/O, just to be safe.
- */
- if (dm_queue_merge_is_compulsory(q) && !ti->type->merge)
- blk_limits_max_hw_sectors(limits,
- (unsigned int) (PAGE_SIZE >> 9));
return 0;
}
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 4934789..2a4b677 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -3566,20 +3566,6 @@ static int pool_iterate_devices(struct dm_target *ti,
return fn(ti, pt->data_dev, 0, ti->len, data);
}
-static int pool_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
- struct bio_vec *biovec, int max_size)
-{
- struct pool_c *pt = ti->private;
- struct request_queue *q = bdev_get_queue(pt->data_dev->bdev);
-
- if (!q->merge_bvec_fn)
- return max_size;
-
- bvm->bi_bdev = pt->data_dev->bdev;
-
- return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
-}
-
static void set_discard_limits(struct pool_c *pt, struct queue_limits *limits)
{
struct pool *pool = pt->pool;
@@ -3671,7 +3657,6 @@ static struct target_type pool_target = {
.resume = pool_resume,
.message = pool_message,
.status = pool_status,
- .merge = pool_merge,
.iterate_devices = pool_iterate_devices,
.io_hints = pool_io_hints,
};
@@ -3996,21 +3981,6 @@ err:
DMEMIT("Error");
}
-static int thin_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
- struct bio_vec *biovec, int max_size)
-{
- struct thin_c *tc = ti->private;
- struct request_queue *q = bdev_get_queue(tc->pool_dev->bdev);
-
- if (!q->merge_bvec_fn)
- return max_size;
-
- bvm->bi_bdev = tc->pool_dev->bdev;
- bvm->bi_sector = dm_target_offset(ti, bvm->bi_sector);
-
- return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
-}
-
static int thin_iterate_devices(struct dm_target *ti,
iterate_devices_callout_fn fn, void *data)
{
@@ -4045,7 +4015,6 @@ static struct target_type thin_target = {
.presuspend = thin_presuspend,
.postsuspend = thin_postsuspend,
.status = thin_status,
- .merge = thin_merge,
.iterate_devices = thin_iterate_devices,
};
diff --git a/drivers/md/dm-verity.c b/drivers/md/dm-verity.c
index 7a7bab8..25d76a8 100644
--- a/drivers/md/dm-verity.c
+++ b/drivers/md/dm-verity.c
@@ -564,21 +564,6 @@ static int verity_ioctl(struct dm_target *ti, unsigned cmd,
cmd, arg);
}
-static int verity_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
- struct bio_vec *biovec, int max_size)
-{
- struct dm_verity *v = ti->private;
- struct request_queue *q = bdev_get_queue(v->data_dev->bdev);
-
- if (!q->merge_bvec_fn)
- return max_size;
-
- bvm->bi_bdev = v->data_dev->bdev;
- bvm->bi_sector = verity_map_sector(v, bvm->bi_sector);
-
- return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
-}
-
static int verity_iterate_devices(struct dm_target *ti,
iterate_devices_callout_fn fn, void *data)
{
@@ -872,7 +857,6 @@ static struct target_type verity_target = {
.map = verity_map,
.status = verity_status,
.ioctl = verity_ioctl,
- .merge = verity_merge,
.iterate_devices = verity_iterate_devices,
.io_hints = verity_io_hints,
};
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index fe1e9b7..90777df 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -116,9 +116,8 @@ EXPORT_SYMBOL_GPL(dm_get_rq_mapinfo);
#define DMF_FREEING 3
#define DMF_DELETING 4
#define DMF_NOFLUSH_SUSPENDING 5
-#define DMF_MERGE_IS_OPTIONAL 6
-#define DMF_DEFERRED_REMOVE 7
-#define DMF_SUSPENDED_INTERNALLY 8
+#define DMF_DEFERRED_REMOVE 6
+#define DMF_SUSPENDED_INTERNALLY 7
/*
* A dummy definition to make RCU happy.
@@ -1586,60 +1585,6 @@ static void __split_and_process_bio(struct mapped_device *md,
* CRUD END
*---------------------------------------------------------------*/
-static int dm_merge_bvec(struct request_queue *q,
- struct bvec_merge_data *bvm,
- struct bio_vec *biovec)
-{
- struct mapped_device *md = q->queuedata;
- struct dm_table *map = dm_get_live_table_fast(md);
- struct dm_target *ti;
- sector_t max_sectors;
- int max_size = 0;
-
- if (unlikely(!map))
- goto out;
-
- ti = dm_table_find_target(map, bvm->bi_sector);
- if (!dm_target_is_valid(ti))
- goto out;
-
- /*
- * Find maximum amount of I/O that won't need splitting
- */
- max_sectors = min(max_io_len(bvm->bi_sector, ti),
- (sector_t) queue_max_sectors(q));
- max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size;
- if (unlikely(max_size < 0)) /* this shouldn't _ever_ happen */
- max_size = 0;
-
- /*
- * merge_bvec_fn() returns number of bytes
- * it can accept at this offset
- * max is precomputed maximal io size
- */
- if (max_size && ti->type->merge)
- max_size = ti->type->merge(ti, bvm, biovec, max_size);
- /*
- * If the target doesn't support merge method and some of the devices
- * provided their merge_bvec method (we know this by looking for the
- * max_hw_sectors that dm_set_device_limits may set), then we can't
- * allow bios with multiple vector entries. So always set max_size
- * to 0, and the code below allows just one page.
- */
- else if (queue_max_hw_sectors(q) <= PAGE_SIZE >> 9)
- max_size = 0;
-
-out:
- dm_put_live_table_fast(md);
- /*
- * Always allow an entire first page
- */
- if (max_size <= biovec->bv_len && !(bvm->bi_size >> SECTOR_SHIFT))
- max_size = biovec->bv_len;
-
- return max_size;
-}
-
/*
* The request function that just remaps the bio built up by
* dm_merge_bvec.
@@ -2030,7 +1975,6 @@ static void dm_init_md_queue(struct mapped_device *md)
md->queue->backing_dev_info.congested_data = md;
blk_queue_make_request(md->queue, dm_request);
blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY);
- blk_queue_merge_bvec(md->queue, dm_merge_bvec);
}
/*
@@ -2241,59 +2185,6 @@ static void __set_size(struct mapped_device *md, sector_t size)
}
/*
- * Return 1 if the queue has a compulsory merge_bvec_fn function.
- *
- * If this function returns 0, then the device is either a non-dm
- * device without a merge_bvec_fn, or it is a dm device that is
- * able to split any bios it receives that are too big.
- */
-int dm_queue_merge_is_compulsory(struct request_queue *q)
-{
- struct mapped_device *dev_md;
-
- if (!q->merge_bvec_fn)
- return 0;
-
- if (q->make_request_fn == dm_request) {
- dev_md = q->queuedata;
- if (test_bit(DMF_MERGE_IS_OPTIONAL, &dev_md->flags))
- return 0;
- }
-
- return 1;
-}
-
-static int dm_device_merge_is_compulsory(struct dm_target *ti,
- struct dm_dev *dev, sector_t start,
- sector_t len, void *data)
-{
- struct block_device *bdev = dev->bdev;
- struct request_queue *q = bdev_get_queue(bdev);
-
- return dm_queue_merge_is_compulsory(q);
-}
-
-/*
- * Return 1 if it is acceptable to ignore merge_bvec_fn based
- * on the properties of the underlying devices.
- */
-static int dm_table_merge_is_optional(struct dm_table *table)
-{
- unsigned i = 0;
- struct dm_target *ti;
-
- while (i < dm_table_get_num_targets(table)) {
- ti = dm_table_get_target(table, i++);
-
- if (ti->type->iterate_devices &&
- ti->type->iterate_devices(ti, dm_device_merge_is_compulsory, NULL))
- return 0;
- }
-
- return 1;
-}
-
-/*
* Returns old map, which caller must destroy.
*/
static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t,
@@ -2302,7 +2193,6 @@ static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t,
struct dm_table *old_map;
struct request_queue *q = md->queue;
sector_t size;
- int merge_is_optional;
size = dm_table_get_size(t);
@@ -2328,17 +2218,11 @@ static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t,
__bind_mempools(md, t);
- merge_is_optional = dm_table_merge_is_optional(t);
-
old_map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock));
rcu_assign_pointer(md->map, t);
md->immutable_target_type = dm_table_get_immutable_target_type(t);
dm_table_set_restrictions(t, q, limits);
- if (merge_is_optional)
- set_bit(DMF_MERGE_IS_OPTIONAL, &md->flags);
- else
- clear_bit(DMF_MERGE_IS_OPTIONAL, &md->flags);
if (old_map)
dm_sync_table(md);
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 84b0f9e4..08f47fc 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -76,8 +76,6 @@ bool dm_table_request_based(struct dm_table *t);
void dm_table_free_md_mempools(struct dm_table *t);
struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
-int dm_queue_merge_is_compulsory(struct request_queue *q);
-
void dm_lock_md_type(struct mapped_device *md);
void dm_unlock_md_type(struct mapped_device *md);
void dm_set_md_type(struct mapped_device *md, unsigned type);
diff --git a/drivers/md/linear.c b/drivers/md/linear.c
index 64713b7..d831a5b 100644
--- a/drivers/md/linear.c
+++ b/drivers/md/linear.c
@@ -52,51 +52,6 @@ static inline struct dev_info *which_dev(struct mddev *mddev, sector_t sector)
return conf->disks + lo;
}
-/**
- * linear_mergeable_bvec -- tell bio layer if two requests can be merged
- * @q: request queue
- * @bvm: properties of new bio
- * @biovec: the request that could be merged to it.
- *
- * Return amount of bytes we can take at this offset
- */
-static int linear_mergeable_bvec(struct request_queue *q,
- struct bvec_merge_data *bvm,
- struct bio_vec *biovec)
-{
- struct mddev *mddev = q->queuedata;
- struct dev_info *dev0;
- unsigned long maxsectors, bio_sectors = bvm->bi_size >> 9;
- sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev);
- int maxbytes = biovec->bv_len;
- struct request_queue *subq;
-
- rcu_read_lock();
- dev0 = which_dev(mddev, sector);
- maxsectors = dev0->end_sector - sector;
- subq = bdev_get_queue(dev0->rdev->bdev);
- if (subq->merge_bvec_fn) {
- bvm->bi_bdev = dev0->rdev->bdev;
- bvm->bi_sector -= dev0->end_sector - dev0->rdev->sectors;
- maxbytes = min(maxbytes, subq->merge_bvec_fn(subq, bvm,
- biovec));
- }
- rcu_read_unlock();
-
- if (maxsectors < bio_sectors)
- maxsectors = 0;
- else
- maxsectors -= bio_sectors;
-
- if (maxsectors <= (PAGE_SIZE >> 9 ) && bio_sectors == 0)
- return maxbytes;
-
- if (maxsectors > (maxbytes >> 9))
- return maxbytes;
- else
- return maxsectors << 9;
-}
-
static int linear_congested(void *data, int bits)
{
struct mddev *mddev = data;
@@ -217,7 +172,6 @@ static int linear_run (struct mddev *mddev)
mddev->private = conf;
md_set_array_sectors(mddev, linear_size(mddev, 0, 0));
- blk_queue_merge_bvec(mddev->queue, linear_mergeable_bvec);
mddev->queue->backing_dev_info.congested_fn = linear_congested;
mddev->queue->backing_dev_info.congested_data = mddev;
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 48234eb..0e34b76 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -5033,7 +5033,6 @@ static void md_clean(struct mddev *mddev)
mddev->changed = 0;
mddev->degraded = 0;
mddev->safemode = 0;
- mddev->merge_check_needed = 0;
mddev->bitmap_info.offset = 0;
mddev->bitmap_info.default_offset = 0;
mddev->bitmap_info.default_space = 0;
@@ -5201,7 +5200,6 @@ static int do_md_stop(struct mddev *mddev, int mode,
__md_stop_writes(mddev);
__md_stop(mddev);
- mddev->queue->merge_bvec_fn = NULL;
mddev->queue->backing_dev_info.congested_fn = NULL;
/* tell userspace to handle 'inactive' */
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 03cec5b..4932445 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -132,10 +132,6 @@ enum flag_bits {
Bitmap_sync, /* ..actually, not quite In_sync. Need a
* bitmap-based recovery to get fully in sync
*/
- Unmerged, /* device is being added to array and should
- * be considerred for bvec_merge_fn but not
- * yet for actual IO
- */
WriteMostly, /* Avoid reading if at all possible */
AutoDetected, /* added by auto-detect */
Blocked, /* An error occurred but has not yet
@@ -366,10 +362,6 @@ struct mddev {
int degraded; /* whether md should consider
* adding a spare
*/
- int merge_check_needed; /* at least one
- * member device
- * has a
- * merge_bvec_fn */
atomic_t recovery_active; /* blocks scheduled, but not written */
wait_queue_head_t recovery_wait;
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index 399272f..2f82954 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -261,18 +261,6 @@ static int multipath_add_disk(struct mddev *mddev, struct md_rdev *rdev)
disk_stack_limits(mddev->gendisk, rdev->bdev,
rdev->data_offset << 9);
- /* as we don't honour merge_bvec_fn, we must never risk
- * violating it, so limit ->max_segments to one, lying
- * within a single page.
- * (Note: it is very unlikely that a device with
- * merge_bvec_fn will be involved in multipath.)
- */
- if (q->merge_bvec_fn) {
- blk_queue_max_segments(mddev->queue, 1);
- blk_queue_segment_boundary(mddev->queue,
- PAGE_CACHE_SIZE - 1);
- }
-
spin_lock_irq(&conf->device_lock);
mddev->degraded--;
rdev->raid_disk = path;
@@ -436,15 +424,6 @@ static int multipath_run (struct mddev *mddev)
disk_stack_limits(mddev->gendisk, rdev->bdev,
rdev->data_offset << 9);
- /* as we don't honour merge_bvec_fn, we must never risk
- * violating it, not that we ever expect a device with
- * a merge_bvec_fn to be involved in multipath */
- if (rdev->bdev->bd_disk->queue->merge_bvec_fn) {
- blk_queue_max_segments(mddev->queue, 1);
- blk_queue_segment_boundary(mddev->queue,
- PAGE_CACHE_SIZE - 1);
- }
-
if (!test_bit(Faulty, &rdev->flags))
working_disks++;
}
diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index ba6b85d..bc4c0b6 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -195,9 +195,6 @@ static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf)
disk_stack_limits(mddev->gendisk, rdev1->bdev,
rdev1->data_offset << 9);
- if (rdev1->bdev->bd_disk->queue->merge_bvec_fn)
- conf->has_merge_bvec = 1;
-
if (!smallest || (rdev1->sectors < smallest->sectors))
smallest = rdev1;
cnt++;
@@ -354,59 +351,6 @@ static struct md_rdev *map_sector(struct mddev *mddev, struct strip_zone *zone,
+ sector_div(sector, zone->nb_dev)];
}
-/**
- * raid0_mergeable_bvec -- tell bio layer if two requests can be merged
- * @q: request queue
- * @bvm: properties of new bio
- * @biovec: the request that could be merged to it.
- *
- * Return amount of bytes we can accept at this offset
- */
-static int raid0_mergeable_bvec(struct request_queue *q,
- struct bvec_merge_data *bvm,
- struct bio_vec *biovec)
-{
- struct mddev *mddev = q->queuedata;
- struct r0conf *conf = mddev->private;
- sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev);
- sector_t sector_offset = sector;
- int max;
- unsigned int chunk_sectors = mddev->chunk_sectors;
- unsigned int bio_sectors = bvm->bi_size >> 9;
- struct strip_zone *zone;
- struct md_rdev *rdev;
- struct request_queue *subq;
-
- if (is_power_of_2(chunk_sectors))
- max = (chunk_sectors - ((sector & (chunk_sectors-1))
- + bio_sectors)) << 9;
- else
- max = (chunk_sectors - (sector_div(sector, chunk_sectors)
- + bio_sectors)) << 9;
- if (max < 0)
- max = 0; /* bio_add cannot handle a negative return */
- if (max <= biovec->bv_len && bio_sectors == 0)
- return biovec->bv_len;
- if (max < biovec->bv_len)
- /* too small already, no need to check further */
- return max;
- if (!conf->has_merge_bvec)
- return max;
-
- /* May need to check subordinate device */
- sector = sector_offset;
- zone = find_zone(mddev->private, §or_offset);
- rdev = map_sector(mddev, zone, sector, §or_offset);
- subq = bdev_get_queue(rdev->bdev);
- if (subq->merge_bvec_fn) {
- bvm->bi_bdev = rdev->bdev;
- bvm->bi_sector = sector_offset + zone->dev_start +
- rdev->data_offset;
- return min(max, subq->merge_bvec_fn(subq, bvm, biovec));
- } else
- return max;
-}
-
static sector_t raid0_size(struct mddev *mddev, sector_t sectors, int raid_disks)
{
sector_t array_sectors = 0;
@@ -471,7 +415,6 @@ static int raid0_run(struct mddev *mddev)
mddev->queue->backing_dev_info.ra_pages = 2* stripe;
}
- blk_queue_merge_bvec(mddev->queue, raid0_mergeable_bvec);
dump_zones(mddev);
ret = md_integrity_register(mddev);
diff --git a/drivers/md/raid0.h b/drivers/md/raid0.h
index 05539d9..7127a62 100644
--- a/drivers/md/raid0.h
+++ b/drivers/md/raid0.h
@@ -12,8 +12,6 @@ struct r0conf {
struct md_rdev **devlist; /* lists of rdevs, pointed to
* by strip_zone->dev */
int nr_strip_zones;
- int has_merge_bvec; /* at least one member has
- * a merge_bvec_fn */
};
#endif
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 40b35be..c2f236c 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -551,7 +551,6 @@ static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sect
rdev = rcu_dereference(conf->mirrors[disk].rdev);
if (r1_bio->bios[disk] == IO_BLOCKED
|| rdev == NULL
- || test_bit(Unmerged, &rdev->flags)
|| test_bit(Faulty, &rdev->flags))
continue;
if (!test_bit(In_sync, &rdev->flags) &&
@@ -701,39 +700,6 @@ static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sect
return best_disk;
}
-static int raid1_mergeable_bvec(struct request_queue *q,
- struct bvec_merge_data *bvm,
- struct bio_vec *biovec)
-{
- struct mddev *mddev = q->queuedata;
- struct r1conf *conf = mddev->private;
- sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev);
- int max = biovec->bv_len;
-
- if (mddev->merge_check_needed) {
- int disk;
- rcu_read_lock();
- for (disk = 0; disk < conf->raid_disks * 2; disk++) {
- struct md_rdev *rdev = rcu_dereference(
- conf->mirrors[disk].rdev);
- if (rdev && !test_bit(Faulty, &rdev->flags)) {
- struct request_queue *q =
- bdev_get_queue(rdev->bdev);
- if (q->merge_bvec_fn) {
- bvm->bi_sector = sector +
- rdev->data_offset;
- bvm->bi_bdev = rdev->bdev;
- max = min(max, q->merge_bvec_fn(
- q, bvm, biovec));
- }
- }
- }
- rcu_read_unlock();
- }
- return max;
-
-}
-
int md_raid1_congested(struct mddev *mddev, int bits)
{
struct r1conf *conf = mddev->private;
@@ -1266,8 +1232,7 @@ read_again:
break;
}
r1_bio->bios[i] = NULL;
- if (!rdev || test_bit(Faulty, &rdev->flags)
- || test_bit(Unmerged, &rdev->flags)) {
+ if (!rdev || test_bit(Faulty, &rdev->flags)) {
if (i < conf->raid_disks)
set_bit(R1BIO_Degraded, &r1_bio->state);
continue;
@@ -1611,7 +1576,6 @@ static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev)
struct raid1_info *p;
int first = 0;
int last = conf->raid_disks - 1;
- struct request_queue *q = bdev_get_queue(rdev->bdev);
if (mddev->recovery_disabled == conf->recovery_disabled)
return -EBUSY;
@@ -1619,11 +1583,6 @@ static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev)
if (rdev->raid_disk >= 0)
first = last = rdev->raid_disk;
- if (q->merge_bvec_fn) {
- set_bit(Unmerged, &rdev->flags);
- mddev->merge_check_needed = 1;
- }
-
for (mirror = first; mirror <= last; mirror++) {
p = conf->mirrors+mirror;
if (!p->rdev) {
@@ -1655,19 +1614,6 @@ static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev)
break;
}
}
- if (err == 0 && test_bit(Unmerged, &rdev->flags)) {
- /* Some requests might not have seen this new
- * merge_bvec_fn. We must wait for them to complete
- * before merging the device fully.
- * First we make sure any code which has tested
- * our function has submitted the request, then
- * we wait for all outstanding requests to complete.
- */
- synchronize_sched();
- freeze_array(conf, 0);
- unfreeze_array(conf);
- clear_bit(Unmerged, &rdev->flags);
- }
md_integrity_add_rdev(rdev, mddev);
if (mddev->queue && blk_queue_discard(bdev_get_queue(rdev->bdev)))
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue);
@@ -2810,8 +2756,6 @@ static struct r1conf *setup_conf(struct mddev *mddev)
goto abort;
disk->rdev = rdev;
q = bdev_get_queue(rdev->bdev);
- if (q->merge_bvec_fn)
- mddev->merge_check_needed = 1;
disk->head_position = 0;
disk->seq_start = MaxSector;
@@ -2957,7 +2901,6 @@ static int run(struct mddev *mddev)
if (mddev->queue) {
mddev->queue->backing_dev_info.congested_fn = raid1_congested;
mddev->queue->backing_dev_info.congested_data = mddev;
- blk_queue_merge_bvec(mddev->queue, raid1_mergeable_bvec);
if (discard_supported)
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD,
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 4a40354..08772a9 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -672,94 +672,6 @@ static sector_t raid10_find_virt(struct r10conf *conf, sector_t sector, int dev)
return (vchunk << geo->chunk_shift) + offset;
}
-/**
- * raid10_mergeable_bvec -- tell bio layer if a two requests can be merged
- * @q: request queue
- * @bvm: properties of new bio
- * @biovec: the request that could be merged to it.
- *
- * Return amount of bytes we can accept at this offset
- * This requires checking for end-of-chunk if near_copies != raid_disks,
- * and for subordinate merge_bvec_fns if merge_check_needed.
- */
-static int raid10_mergeable_bvec(struct request_queue *q,
- struct bvec_merge_data *bvm,
- struct bio_vec *biovec)
-{
- struct mddev *mddev = q->queuedata;
- struct r10conf *conf = mddev->private;
- sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev);
- int max;
- unsigned int chunk_sectors;
- unsigned int bio_sectors = bvm->bi_size >> 9;
- struct geom *geo = &conf->geo;
-
- chunk_sectors = (conf->geo.chunk_mask & conf->prev.chunk_mask) + 1;
- if (conf->reshape_progress != MaxSector &&
- ((sector >= conf->reshape_progress) !=
- conf->mddev->reshape_backwards))
- geo = &conf->prev;
-
- if (geo->near_copies < geo->raid_disks) {
- max = (chunk_sectors - ((sector & (chunk_sectors - 1))
- + bio_sectors)) << 9;
- if (max < 0)
- /* bio_add cannot handle a negative return */
- max = 0;
- if (max <= biovec->bv_len && bio_sectors == 0)
- return biovec->bv_len;
- } else
- max = biovec->bv_len;
-
- if (mddev->merge_check_needed) {
- struct {
- struct r10bio r10_bio;
- struct r10dev devs[conf->copies];
- } on_stack;
- struct r10bio *r10_bio = &on_stack.r10_bio;
- int s;
- if (conf->reshape_progress != MaxSector) {
- /* Cannot give any guidance during reshape */
- if (max <= biovec->bv_len && bio_sectors == 0)
- return biovec->bv_len;
- return 0;
- }
- r10_bio->sector = sector;
- raid10_find_phys(conf, r10_bio);
- rcu_read_lock();
- for (s = 0; s < conf->copies; s++) {
- int disk = r10_bio->devs[s].devnum;
- struct md_rdev *rdev = rcu_dereference(
- conf->mirrors[disk].rdev);
- if (rdev && !test_bit(Faulty, &rdev->flags)) {
- struct request_queue *q =
- bdev_get_queue(rdev->bdev);
- if (q->merge_bvec_fn) {
- bvm->bi_sector = r10_bio->devs[s].addr
- + rdev->data_offset;
- bvm->bi_bdev = rdev->bdev;
- max = min(max, q->merge_bvec_fn(
- q, bvm, biovec));
- }
- }
- rdev = rcu_dereference(conf->mirrors[disk].replacement);
- if (rdev && !test_bit(Faulty, &rdev->flags)) {
- struct request_queue *q =
- bdev_get_queue(rdev->bdev);
- if (q->merge_bvec_fn) {
- bvm->bi_sector = r10_bio->devs[s].addr
- + rdev->data_offset;
- bvm->bi_bdev = rdev->bdev;
- max = min(max, q->merge_bvec_fn(
- q, bvm, biovec));
- }
- }
- }
- rcu_read_unlock();
- }
- return max;
-}
-
/*
* This routine returns the disk from which the requested read should
* be done. There is a per-array 'next expected sequential IO' sector
@@ -822,12 +734,10 @@ retry:
disk = r10_bio->devs[slot].devnum;
rdev = rcu_dereference(conf->mirrors[disk].replacement);
if (rdev == NULL || test_bit(Faulty, &rdev->flags) ||
- test_bit(Unmerged, &rdev->flags) ||
r10_bio->devs[slot].addr + sectors > rdev->recovery_offset)
rdev = rcu_dereference(conf->mirrors[disk].rdev);
if (rdev == NULL ||
- test_bit(Faulty, &rdev->flags) ||
- test_bit(Unmerged, &rdev->flags))
+ test_bit(Faulty, &rdev->flags))
continue;
if (!test_bit(In_sync, &rdev->flags) &&
r10_bio->devs[slot].addr + sectors > rdev->recovery_offset)
@@ -1336,11 +1246,9 @@ retry_write:
blocked_rdev = rrdev;
break;
}
- if (rdev && (test_bit(Faulty, &rdev->flags)
- || test_bit(Unmerged, &rdev->flags)))
+ if (rdev && (test_bit(Faulty, &rdev->flags)))
rdev = NULL;
- if (rrdev && (test_bit(Faulty, &rrdev->flags)
- || test_bit(Unmerged, &rrdev->flags)))
+ if (rrdev && (test_bit(Faulty, &rrdev->flags)))
rrdev = NULL;
r10_bio->devs[i].bio = NULL;
@@ -1787,7 +1695,6 @@ static int raid10_add_disk(struct mddev *mddev, struct md_rdev *rdev)
int mirror;
int first = 0;
int last = conf->geo.raid_disks - 1;
- struct request_queue *q = bdev_get_queue(rdev->bdev);
if (mddev->recovery_cp < MaxSector)
/* only hot-add to in-sync arrays, as recovery is
@@ -1800,11 +1707,6 @@ static int raid10_add_disk(struct mddev *mddev, struct md_rdev *rdev)
if (rdev->raid_disk >= 0)
first = last = rdev->raid_disk;
- if (q->merge_bvec_fn) {
- set_bit(Unmerged, &rdev->flags);
- mddev->merge_check_needed = 1;
- }
-
if (rdev->saved_raid_disk >= first &&
conf->mirrors[rdev->saved_raid_disk].rdev == NULL)
mirror = rdev->saved_raid_disk;
@@ -1843,19 +1745,6 @@ static int raid10_add_disk(struct mddev *mddev, struct md_rdev *rdev)
rcu_assign_pointer(p->rdev, rdev);
break;
}
- if (err == 0 && test_bit(Unmerged, &rdev->flags)) {
- /* Some requests might not have seen this new
- * merge_bvec_fn. We must wait for them to complete
- * before merging the device fully.
- * First we make sure any code which has tested
- * our function has submitted the request, then
- * we wait for all outstanding requests to complete.
- */
- synchronize_sched();
- freeze_array(conf, 0);
- unfreeze_array(conf);
- clear_bit(Unmerged, &rdev->flags);
- }
md_integrity_add_rdev(rdev, mddev);
if (mddev->queue && blk_queue_discard(bdev_get_queue(rdev->bdev)))
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue);
@@ -2404,7 +2293,6 @@ static void fix_read_error(struct r10conf *conf, struct mddev *mddev, struct r10
d = r10_bio->devs[sl].devnum;
rdev = rcu_dereference(conf->mirrors[d].rdev);
if (rdev &&
- !test_bit(Unmerged, &rdev->flags) &&
test_bit(In_sync, &rdev->flags) &&
is_badblock(rdev, r10_bio->devs[sl].addr + sect, s,
&first_bad, &bad_sectors) == 0) {
@@ -2458,7 +2346,6 @@ static void fix_read_error(struct r10conf *conf, struct mddev *mddev, struct r10
d = r10_bio->devs[sl].devnum;
rdev = rcu_dereference(conf->mirrors[d].rdev);
if (!rdev ||
- test_bit(Unmerged, &rdev->flags) ||
!test_bit(In_sync, &rdev->flags))
continue;
@@ -3657,8 +3544,6 @@ static int run(struct mddev *mddev)
disk->rdev = rdev;
}
q = bdev_get_queue(rdev->bdev);
- if (q->merge_bvec_fn)
- mddev->merge_check_needed = 1;
diff = (rdev->new_data_offset - rdev->data_offset);
if (!mddev->reshape_backwards)
diff = -diff;
@@ -3757,7 +3642,6 @@ static int run(struct mddev *mddev)
stripe /= conf->geo.near_copies;
if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe)
mddev->queue->backing_dev_info.ra_pages = 2 * stripe;
- blk_queue_merge_bvec(mddev->queue, raid10_mergeable_bvec);
}
if (md_integrity_register(mddev))
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 40e464c..6008a30 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -4103,32 +4103,6 @@ static int raid5_congested(void *data, int bits)
md_raid5_congested(mddev, bits);
}
-/* We want read requests to align with chunks where possible,
- * but write requests don't need to.
- */
-static int raid5_mergeable_bvec(struct request_queue *q,
- struct bvec_merge_data *bvm,
- struct bio_vec *biovec)
-{
- struct mddev *mddev = q->queuedata;
- sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev);
- int max;
- unsigned int chunk_sectors = mddev->chunk_sectors;
- unsigned int bio_sectors = bvm->bi_size >> 9;
-
- if ((bvm->bi_rw & 1) == WRITE)
- return biovec->bv_len; /* always allow writes to be mergeable */
-
- if (mddev->new_chunk_sectors < mddev->chunk_sectors)
- chunk_sectors = mddev->new_chunk_sectors;
- max = (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9;
- if (max < 0) max = 0;
- if (max <= biovec->bv_len && bio_sectors == 0)
- return biovec->bv_len;
- else
- return max;
-}
-
static int in_chunk_boundary(struct mddev *mddev, struct bio *bio)
{
sector_t sector = bio->bi_iter.bi_sector + get_start_sect(bio->bi_bdev);
@@ -6152,8 +6126,6 @@ static int run(struct mddev *mddev)
if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe)
mddev->queue->backing_dev_info.ra_pages = 2 * stripe;
- blk_queue_merge_bvec(mddev->queue, raid5_mergeable_bvec);
-
mddev->queue->backing_dev_info.congested_data = mddev;
mddev->queue->backing_dev_info.congested_fn = raid5_congested;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index c03e37a..7a8c95c 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -239,14 +239,6 @@ typedef int (prep_rq_fn) (struct request_queue *, struct request *);
typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
struct bio_vec;
-struct bvec_merge_data {
- struct block_device *bi_bdev;
- sector_t bi_sector;
- unsigned bi_size;
- unsigned long bi_rw;
-};
-typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *,
- struct bio_vec *);
typedef void (softirq_done_fn)(struct request *);
typedef int (dma_drain_needed_fn)(struct request *);
typedef int (lld_busy_fn) (struct request_queue *q);
@@ -327,7 +319,6 @@ struct request_queue {
make_request_fn *make_request_fn;
prep_rq_fn *prep_rq_fn;
unprep_rq_fn *unprep_rq_fn;
- merge_bvec_fn *merge_bvec_fn;
softirq_done_fn *softirq_done_fn;
rq_timed_out_fn *rq_timed_out_fn;
dma_drain_needed_fn *dma_drain_needed;
@@ -1036,7 +1027,6 @@ extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
-extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *);
extern void blk_queue_dma_alignment(struct request_queue *, int);
extern void blk_queue_update_dma_alignment(struct request_queue *, int);
extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index ca6d2acc..2f7f2df 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -77,9 +77,6 @@ typedef int (*dm_message_fn) (struct dm_target *ti, unsigned argc, char **argv);
typedef int (*dm_ioctl_fn) (struct dm_target *ti, unsigned int cmd,
unsigned long arg);
-typedef int (*dm_merge_fn) (struct dm_target *ti, struct bvec_merge_data *bvm,
- struct bio_vec *biovec, int max_size);
-
/*
* These iteration functions are typically used to check (and combine)
* properties of underlying devices.
@@ -153,7 +150,6 @@ struct target_type {
dm_status_fn status;
dm_message_fn message;
dm_ioctl_fn ioctl;
- dm_merge_fn merge;
dm_busy_fn busy;
dm_iterate_devices_fn iterate_devices;
dm_io_hints_fn io_hints;
--
2.1.0
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v2 8/9] fs: use helper bio_add_page() instead of open coding on bi_io_vec
2015-01-12 11:49 [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs Dongsu Park
` (6 preceding siblings ...)
2015-01-12 11:49 ` [PATCH v2 7/9] block: kill merge_bvec_fn() completely Dongsu Park
@ 2015-01-12 11:49 ` Dongsu Park
2015-01-12 11:49 ` [PATCH v2 9/9] Documentation: update notes in biovecs about arbitrarily sized bios Dongsu Park
2015-01-15 17:12 ` [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs Christoph Hellwig
9 siblings, 0 replies; 11+ messages in thread
From: Dongsu Park @ 2015-01-12 11:49 UTC (permalink / raw)
To: linux-kernel
Cc: Christoph Hellwig, Kent Overstreet, Jens Axboe, Al Viro,
linux-fsdevel, Dongsu Park
From: Kent Overstreet <kmo@daterainc.com>
Call pre-defined helper bio_add_page() instead of open coding for
iterating through bi_io_vec[]. Doing that, it's possible to make some
parts in filesystems and mm/page_io.c simpler than before.
Acked-by: Dave Kleikamp <shaggy@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
[dpark: add more description in commit message]
Signed-off-by: Dongsu Park <dongsu.park@profitbricks.com>
---
fs/buffer.c | 7 ++-----
fs/jfs/jfs_logmgr.c | 14 ++++----------
mm/page_io.c | 8 +++-----
3 files changed, 9 insertions(+), 20 deletions(-)
diff --git a/fs/buffer.c b/fs/buffer.c
index dbe5699..78e63e3 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -3022,12 +3022,9 @@ int _submit_bh(int rw, struct buffer_head *bh, unsigned long bio_flags)
bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
bio->bi_bdev = bh->b_bdev;
- bio->bi_io_vec[0].bv_page = bh->b_page;
- bio->bi_io_vec[0].bv_len = bh->b_size;
- bio->bi_io_vec[0].bv_offset = bh_offset(bh);
- bio->bi_vcnt = 1;
- bio->bi_iter.bi_size = bh->b_size;
+ bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh));
+ BUG_ON(bio->bi_iter.bi_size != bh->b_size);
bio->bi_end_io = end_bio_bh_io_sync;
bio->bi_private = bh;
diff --git a/fs/jfs/jfs_logmgr.c b/fs/jfs/jfs_logmgr.c
index bc462dc..46fae06 100644
--- a/fs/jfs/jfs_logmgr.c
+++ b/fs/jfs/jfs_logmgr.c
@@ -1999,12 +1999,9 @@ static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp)
bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
bio->bi_bdev = log->bdev;
- bio->bi_io_vec[0].bv_page = bp->l_page;
- bio->bi_io_vec[0].bv_len = LOGPSIZE;
- bio->bi_io_vec[0].bv_offset = bp->l_offset;
- bio->bi_vcnt = 1;
- bio->bi_iter.bi_size = LOGPSIZE;
+ bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
+ BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
bio->bi_end_io = lbmIODone;
bio->bi_private = bp;
@@ -2145,12 +2142,9 @@ static void lbmStartIO(struct lbuf * bp)
bio = bio_alloc(GFP_NOFS, 1);
bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
bio->bi_bdev = log->bdev;
- bio->bi_io_vec[0].bv_page = bp->l_page;
- bio->bi_io_vec[0].bv_len = LOGPSIZE;
- bio->bi_io_vec[0].bv_offset = bp->l_offset;
- bio->bi_vcnt = 1;
- bio->bi_iter.bi_size = LOGPSIZE;
+ bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
+ BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
bio->bi_end_io = lbmIODone;
bio->bi_private = bp;
diff --git a/mm/page_io.c b/mm/page_io.c
index 955db8b..8c878c7 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -33,12 +33,10 @@ static struct bio *get_swap_bio(gfp_t gfp_flags,
if (bio) {
bio->bi_iter.bi_sector = map_swap_page(page, &bio->bi_bdev);
bio->bi_iter.bi_sector <<= PAGE_SHIFT - 9;
- bio->bi_io_vec[0].bv_page = page;
- bio->bi_io_vec[0].bv_len = PAGE_SIZE;
- bio->bi_io_vec[0].bv_offset = 0;
- bio->bi_vcnt = 1;
- bio->bi_iter.bi_size = PAGE_SIZE;
bio->bi_end_io = end_io;
+
+ bio_add_page(bio, page, PAGE_SIZE, 0);
+ BUG_ON(bio->bi_iter.bi_size != PAGE_SIZE);
}
return bio;
}
--
2.1.0
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v2 9/9] Documentation: update notes in biovecs about arbitrarily sized bios
2015-01-12 11:49 [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs Dongsu Park
` (7 preceding siblings ...)
2015-01-12 11:49 ` [PATCH v2 8/9] fs: use helper bio_add_page() instead of open coding on bi_io_vec Dongsu Park
@ 2015-01-12 11:49 ` Dongsu Park
2015-01-15 17:12 ` [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs Christoph Hellwig
9 siblings, 0 replies; 11+ messages in thread
From: Dongsu Park @ 2015-01-12 11:49 UTC (permalink / raw)
To: linux-kernel
Cc: Christoph Hellwig, Kent Overstreet, Jens Axboe, Dongsu Park,
Jonathan Corbet, linux-doc
Update block/biovecs.txt so that it includes a note on what kind of
effects arbitrarily sized bios would bring to the block layer.
Also fix a trivial typo, bio_iter_iovec.
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Signed-off-by: Dongsu Park <dongsu.park@profitbricks.com>
---
Documentation/block/biovecs.txt | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/Documentation/block/biovecs.txt b/Documentation/block/biovecs.txt
index 74a32ad..2568958 100644
--- a/Documentation/block/biovecs.txt
+++ b/Documentation/block/biovecs.txt
@@ -24,7 +24,7 @@ particular, presenting the illusion of partially completed biovecs so that
normal code doesn't have to deal with bi_bvec_done.
* Driver code should no longer refer to biovecs directly; we now have
- bio_iovec() and bio_iovec_iter() macros that return literal struct biovecs,
+ bio_iovec() and bio_iter_iovec() macros that return literal struct biovecs,
constructed from the raw biovecs but taking into account bi_bvec_done and
bi_size.
@@ -109,3 +109,11 @@ Other implications:
over all the biovecs in the new bio - which is silly as it's not needed.
So, don't use bi_vcnt anymore.
+
+ * The current interface allows the block layer to split bios as needed, so we
+ could eliminate a lot of complexity particularly in stacked drivers. Code
+ that creates bios can then create whatever size bios are convenient, and
+ more importantly stacked drivers don't have to deal with both their own bio
+ size limitations and the limitations of the underlying devices. Thus
+ there's no need to define ->merge_bvec_fn() callbacks for individual block
+ drivers.
--
2.1.0
^ permalink raw reply related [flat|nested] 11+ messages in thread* Re: [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs
2015-01-12 11:49 [RFC PATCH v2 0/9] simplify block layer based on immutable biovecs Dongsu Park
` (8 preceding siblings ...)
2015-01-12 11:49 ` [PATCH v2 9/9] Documentation: update notes in biovecs about arbitrarily sized bios Dongsu Park
@ 2015-01-15 17:12 ` Christoph Hellwig
9 siblings, 0 replies; 11+ messages in thread
From: Christoph Hellwig @ 2015-01-15 17:12 UTC (permalink / raw)
To: Dongsu Park; +Cc: linux-kernel, Kent Overstreet, Jens Axboe
> - move a patch "btrfs: make use of immutable biovecs" to the upcoming series.
which upcoming series is that?
^ permalink raw reply [flat|nested] 11+ messages in thread