When we start using immutable biovecs to for efficient bio splitting,
drivers need to be using the new primitives that handle
bvec_iter.bi_bvec_done. Otherwise, this should be eqivalent to the old
code.

Signed-off-by: Kent Overstreet <[email protected]>
Cc: "Ed L. Cashin" <[email protected]>
---
drivers/block/aoe/aoe.h | 10 +---
drivers/block/aoe/aoecmd.c | 130 +++++++++++++++++----------------------------
2 files changed, 51 insertions(+), 89 deletions(-)

diff --git a/drivers/block/aoe/aoe.h b/drivers/block/aoe/aoe.h
index 1756494..e959e6b 100644
--- a/drivers/block/aoe/aoe.h
+++ b/drivers/block/aoe/aoe.h
@@ -100,11 +100,8 @@ enum {

struct buf {
ulong nframesout;
- ulong resid;
- ulong bv_resid;
- sector_t sector;
struct bio *bio;
- struct bio_vec *bv;
+ struct bvec_iter iter;
struct request *rq;
};

@@ -120,13 +117,10 @@ struct frame {
ulong waited;
ulong waited_total;
struct aoetgt *t; /* parent target I belong to */
- sector_t lba;
struct sk_buff *skb; /* command skb freed on module exit */
struct sk_buff *r_skb; /* response skb for async processing */
struct buf *buf;
- struct bio_vec *bv;
- ulong bcnt;
- ulong bv_off;
+ struct bvec_iter iter;
char flags;
};

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index 63acfa1..08422a9 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -182,8 +182,7 @@ aoe_freetframe(struct frame *f)

t = f->t;
f->buf = NULL;
- f->lba = 0;
- f->bv = NULL;
+ memset(&f->iter, 0, sizeof(f->iter));
f->r_skb = NULL;
f->flags = 0;
list_add(&f->head, &t->ffree);
@@ -281,21 +280,17 @@ newframe(struct aoedev *d)
}

static void
-skb_fillup(struct sk_buff *skb, struct bio_vec *bv, ulong off, ulong cnt)
+skb_fillup(struct sk_buff *skb, struct bio *bio, struct bvec_iter *iter)
{
int frag = 0;
- ulong fcnt;
-loop:
- fcnt = bv->bv_len - (off - bv->bv_offset);
- if (fcnt > cnt)
- fcnt = cnt;
- skb_fill_page_desc(skb, frag++, bv->bv_page, off, fcnt);
- cnt -= fcnt;
- if (cnt <= 0)
- return;
- bv++;
- off = bv->bv_offset;
- goto loop;
+
+ while (iter->bi_size) {
+ struct bio_vec bv = bio_iovec_iter(bio, *iter);
+
+ skb_fill_page_desc(skb, frag++, bv.bv_page,
+ bv.bv_offset, bv.bv_len);
+ bio_advance_iter(bio, iter, bv.bv_len);
+ }
}

static void
@@ -332,12 +327,10 @@ ata_rw_frameinit(struct frame *f)
t->nout++;
f->waited = 0;
f->waited_total = 0;
- if (f->buf)
- f->lba = f->buf->sector;

/* set up ata header */
- ah->scnt = f->bcnt >> 9;
- put_lba(ah, f->lba);
+ ah->scnt = f->iter.bi_size >> 9;
+ put_lba(ah, f->iter.bi_sector);
if (t->d->flags & DEVFL_EXT) {
ah->aflags |= AOEAFL_EXT;
} else {
@@ -346,11 +339,11 @@ ata_rw_frameinit(struct frame *f)
ah->lba3 |= 0xe0; /* LBA bit + obsolete 0xa0 */
}
if (f->buf && bio_data_dir(f->buf->bio) == WRITE) {
- skb_fillup(skb, f->bv, f->bv_off, f->bcnt);
+ skb->len += f->iter.bi_size;
+ skb->data_len = f->iter.bi_size;
+ skb->truesize += f->iter.bi_size;
+ skb_fillup(skb, f->buf->bio, &f->iter);
ah->aflags |= AOEAFL_WRITE;
- skb->len += f->bcnt;
- skb->data_len = f->bcnt;
- skb->truesize += f->bcnt;
t->wpkts++;
} else {
t->rpkts++;
@@ -369,7 +362,7 @@ aoecmd_ata_rw(struct aoedev *d)
struct aoetgt *t;
struct sk_buff *skb;
struct sk_buff_head queue;
- ulong bcnt, fbcnt;
+ ulong bcnt;

buf = nextbuf(d);
if (buf == NULL)
@@ -381,36 +374,19 @@ aoecmd_ata_rw(struct aoedev *d)
bcnt = d->maxbcnt;
if (bcnt == 0)
bcnt = DEFAULTBCNT;
- if (bcnt > buf->resid)
- bcnt = buf->resid;
- fbcnt = bcnt;
- f->bv = buf->bv;
- f->bv_off = f->bv->bv_offset + (f->bv->bv_len - buf->bv_resid);
- do {
- if (fbcnt < buf->bv_resid) {
- buf->bv_resid -= fbcnt;
- buf->resid -= fbcnt;
- break;
- }
- fbcnt -= buf->bv_resid;
- buf->resid -= buf->bv_resid;
- if (buf->resid == 0) {
- d->ip.buf = NULL;
- break;
- }
- buf->bv++;
- buf->bv_resid = buf->bv->bv_len;
- WARN_ON(buf->bv_resid == 0);
- } while (fbcnt);
+ if (bcnt > buf->iter.bi_size)
+ bcnt = buf->iter.bi_size;
+
+ bio_advance_iter(buf->bio, &buf->iter, bcnt);

/* initialize the headers & frame */
f->buf = buf;
- f->bcnt = bcnt;
+ f->iter = buf->iter;
+ f->iter.bi_size = bcnt;
ata_rw_frameinit(f);

/* mark all tracking fields and load out */
buf->nframesout += 1;
- buf->sector += bcnt >> 9;

skb = skb_clone(f->skb, GFP_ATOMIC);
if (skb) {
@@ -603,10 +579,7 @@ reassign_frame(struct frame *f)
skb = nf->skb;
nf->skb = f->skb;
nf->buf = f->buf;
- nf->bcnt = f->bcnt;
- nf->lba = f->lba;
- nf->bv = f->bv;
- nf->bv_off = f->bv_off;
+ nf->iter = f->iter;
nf->waited = 0;
nf->waited_total = f->waited_total;
nf->sent = f->sent;
@@ -625,6 +598,7 @@ probe(struct aoetgt *t)
struct sk_buff_head queue;
size_t n, m;
int frag;
+ ulong bcnt;

d = t->d;
f = newtframe(d, t);
@@ -638,19 +612,20 @@ probe(struct aoetgt *t)
}
f->flags |= FFL_PROBE;
ifrotate(t);
- f->bcnt = t->d->maxbcnt ? t->d->maxbcnt : DEFAULTBCNT;
+ bcnt = t->d->maxbcnt ? t->d->maxbcnt : DEFAULTBCNT;
+ f->iter.bi_size = bcnt;
ata_rw_frameinit(f);
skb = f->skb;
- for (frag = 0, n = f->bcnt; n > 0; ++frag, n -= m) {
+ for (frag = 0, n = bcnt; n > 0; ++frag, n -= m) {
if (n < PAGE_SIZE)
m = n;
else
m = PAGE_SIZE;
skb_fill_page_desc(skb, frag, empty_page, 0, m);
}
- skb->len += f->bcnt;
- skb->data_len = f->bcnt;
- skb->truesize += f->bcnt;
+ skb->len += bcnt;
+ skb->data_len = bcnt;
+ skb->truesize += bcnt;

skb = skb_clone(f->skb, GFP_ATOMIC);
if (skb) {
@@ -919,17 +894,11 @@ bio_pagedec(struct bio *bio)
static void
bufinit(struct buf *buf, struct request *rq, struct bio *bio)
{
- struct bio_vec *bv;
-
memset(buf, 0, sizeof(*buf));
buf->rq = rq;
buf->bio = bio;
- buf->resid = bio->bi_iter.bi_size;
- buf->sector = bio->bi_iter.bi_sector;
+ buf->iter = bio->bi_iter;
bio_pageinc(bio);
- buf->bv = bv = __bio_iovec(bio);
- buf->bv_resid = bv->bv_len;
- WARN_ON(buf->bv_resid == 0);
}

static struct buf *
@@ -1114,24 +1083,24 @@ gettgt(struct aoedev *d, char *addr)
}

static void
-bvcpy(struct bio_vec *bv, ulong off, struct sk_buff *skb, long cnt)
+bvcpy(struct sk_buff *skb, struct bio *bio, struct bvec_iter *iter,
+ long cnt)
{
- ulong fcnt;
char *p;
int soff = 0;
-loop:
- fcnt = bv->bv_len - (off - bv->bv_offset);
- if (fcnt > cnt)
- fcnt = cnt;
- p = page_address(bv->bv_page) + off;
- skb_copy_bits(skb, soff, p, fcnt);
- soff += fcnt;
- cnt -= fcnt;
- if (cnt <= 0)
- return;
- bv++;
- off = bv->bv_offset;
- goto loop;
+
+ do {
+ struct bio_vec bv = bio_iovec_iter(bio, *iter);
+
+ p = page_address(bv.bv_page) + bv.bv_offset;
+ skb_copy_bits(skb, soff, p, bv.bv_len);
+
+ bio_advance_iter(bio, iter, bv.bv_len);
+ soff += bv.bv_len;
+ cnt -= bv.bv_len;
+ if (cnt <= 0)
+ return;
+ } while (cnt > 0);
}

void
@@ -1224,7 +1193,7 @@ noskb: if (buf)
clear_bit(BIO_UPTODATE, &buf->bio->bi_flags);
break;
}
- bvcpy(f->bv, f->bv_off, skb, n);
+ bvcpy(skb, f->buf->bio, &f->iter, n);
case ATA_CMD_PIO_WRITE:
case ATA_CMD_PIO_WRITE_EXT:
spin_lock_irq(&d->lock);
@@ -1267,7 +1236,7 @@ out:

aoe_freetframe(f);

- if (buf && --buf->nframesout == 0 && buf->resid == 0)
+ if (buf && --buf->nframesout == 0 && buf->iter.bi_size == 0)
aoe_end_buf(d, buf);

spin_unlock_irq(&d->lock);
@@ -1698,7 +1667,6 @@ aoe_failbuf(struct aoedev *d, struct buf *buf)
{
if (buf == NULL)
return;
- buf->resid = 0;
clear_bit(BIO_UPTODATE, &buf->bio->bi_flags);
if (buf->nframesout == 0)
aoe_end_buf(d, buf);
--
1.8.1.3

2013-03-27 17:47:07

by Kent Overstreet

[permalink] [raw]

Subject: [PATCH 07/22] dm-verity: convert to bvec iter

Use the new primitives which respect the current value of bi_idx and
bi_bvec_done.

Signed-off-by: Kent Overstreet <[email protected]>
Cc: Alasdair Kergon <[email protected]>
Cc: [email protected]
---
drivers/md/dm-verity.c | 51 +++++++++++++-------------------------------------
1 file changed, 13 insertions(+), 38 deletions(-)

diff --git a/drivers/md/dm-verity.c b/drivers/md/dm-verity.c
index 782ee42..2d01c33 100644
--- a/drivers/md/dm-verity.c
+++ b/drivers/md/dm-verity.c
@@ -73,15 +73,10 @@ struct dm_verity_io {
sector_t block;
unsigned n_blocks;

- /* saved bio vector */
- struct bio_vec *io_vec;
- unsigned io_vec_size;
+ struct bvec_iter iter;

struct work_struct work;

- /* A space for short vectors; longer vectors are allocated separately. */
- struct bio_vec io_vec_inline[DM_VERITY_IO_VEC_INLINE];
-
/*
* Three variably-size fields follow this struct:
*
@@ -277,9 +272,9 @@ release_ret_r:
static int verity_verify_io(struct dm_verity_io *io)
{
struct dm_verity *v = io->v;
+ struct bio *bio = dm_bio_from_per_bio_data(io, v->ti->per_bio_data_size);
unsigned b;
int i;
- unsigned vector = 0, offset = 0;

for (b = 0; b < io->n_blocks; b++) {
struct shash_desc *desc;
@@ -329,31 +324,22 @@ test_block_hash:
}

todo = 1 << v->data_dev_block_bits;
- do {
- struct bio_vec *bv;
+ while (io->iter.bi_size) {
u8 *page;
- unsigned len;
-
- BUG_ON(vector >= io->io_vec_size);
- bv = &io->io_vec[vector];
- page = kmap_atomic(bv->bv_page);
- len = bv->bv_len - offset;
- if (likely(len >= todo))
- len = todo;
- r = crypto_shash_update(desc,
- page + bv->bv_offset + offset, len);
+ struct bio_vec bv = bio_iovec_iter(bio, io->iter);
+
+ page = kmap_atomic(bv.bv_page);
+ r = crypto_shash_update(desc, page + bv.bv_offset,
+ bv.bv_len);
kunmap_atomic(page);
+
if (r < 0) {
DMERR("crypto_shash_update failed: %d", r);
return r;
}
- offset += len;
- if (likely(offset == bv->bv_len)) {
- offset = 0;
- vector++;
- }
- todo -= len;
- } while (todo);
+
+ bio_advance_iter(bio, &io->iter, bv.bv_len);
+ }

if (!v->version) {
r = crypto_shash_update(desc, v->salt, v->salt_size);
@@ -376,8 +362,6 @@ test_block_hash:
return -EIO;
}
}
- BUG_ON(vector != io->io_vec_size);
- BUG_ON(offset);

return 0;
}
@@ -393,9 +377,6 @@ static void verity_finish_io(struct dm_verity_io *io, int error)
bio->bi_end_io = io->orig_bi_end_io;
bio->bi_private = io->orig_bi_private;

- if (io->io_vec != io->io_vec_inline)
- mempool_free(io->io_vec, v->vec_mempool);
-
bio_endio(bio, error);
}

@@ -491,13 +472,7 @@ static int verity_map(struct dm_target *ti, struct bio *bio)

bio->bi_end_io = verity_end_io;
bio->bi_private = io;
- io->io_vec_size = bio_segments(bio);
- if (io->io_vec_size < DM_VERITY_IO_VEC_INLINE)
- io->io_vec = io->io_vec_inline;
- else
- io->io_vec = mempool_alloc(v->vec_mempool, GFP_NOIO);
- memcpy(io->io_vec, __bio_iovec(bio),
- io->io_vec_size * sizeof(struct bio_vec));
+ io->iter = bio->bi_iter;

verity_prefetch_io(v, io);

--
1.8.1.3