aoe: zero copy write 2 of 2
Avoid memory copy on writes. (This patch follows patch 4.) Signed-off-by: "Ed L. Cashin" <ecashin@coraid.com> Acked-by: Alan Cox <alan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
parent
dced3a053d
commit
4f51dc5e9a
3 changed files with 64 additions and 20 deletions
|
@ -84,6 +84,7 @@ enum {
|
|||
DEVFL_PAUSE = (1<<5),
|
||||
DEVFL_NEWSIZE = (1<<6), /* need to update dev size in block layer */
|
||||
DEVFL_MAXBCNT = (1<<7), /* d->maxbcnt is not changeable */
|
||||
DEVFL_KICKME = (1<<8),
|
||||
|
||||
BUFFL_FAIL = 1,
|
||||
};
|
||||
|
|
|
@ -120,7 +120,7 @@ aoecmd_ata_rw(struct aoedev *d, struct frame *f)
|
|||
h = (struct aoe_hdr *) skb->mac.raw;
|
||||
ah = (struct aoe_atahdr *) (h+1);
|
||||
skb->len = sizeof *h + sizeof *ah;
|
||||
memset(h, 0, skb->len);
|
||||
memset(h, 0, ETH_ZLEN);
|
||||
f->tag = aoehdr_atainit(d, h);
|
||||
f->waited = 0;
|
||||
f->buf = buf;
|
||||
|
@ -143,8 +143,9 @@ aoecmd_ata_rw(struct aoedev *d, struct frame *f)
|
|||
skb_fill_page_desc(skb, 0, virt_to_page(f->bufaddr),
|
||||
offset_in_page(f->bufaddr), bcnt);
|
||||
ah->aflags |= AOEAFL_WRITE;
|
||||
skb->len += bcnt;
|
||||
skb->data_len = bcnt;
|
||||
} else {
|
||||
skb_shinfo(skb)->nr_frags = 0;
|
||||
skb->len = ETH_ZLEN;
|
||||
writebit = 0;
|
||||
}
|
||||
|
@ -167,8 +168,9 @@ aoecmd_ata_rw(struct aoedev *d, struct frame *f)
|
|||
}
|
||||
|
||||
skb->dev = d->ifp;
|
||||
skb_get(skb);
|
||||
skb->next = NULL;
|
||||
skb = skb_clone(skb, GFP_ATOMIC);
|
||||
if (skb == NULL)
|
||||
return;
|
||||
if (d->sendq_hd)
|
||||
d->sendq_tl->next = skb;
|
||||
else
|
||||
|
@ -224,6 +226,29 @@ aoecmd_cfg_pkts(ushort aoemajor, unsigned char aoeminor, struct sk_buff **tail)
|
|||
return sl;
|
||||
}
|
||||
|
||||
static struct frame *
|
||||
freeframe(struct aoedev *d)
|
||||
{
|
||||
struct frame *f, *e;
|
||||
int n = 0;
|
||||
|
||||
f = d->frames;
|
||||
e = f + d->nframes;
|
||||
for (; f<e; f++) {
|
||||
if (f->tag != FREETAG)
|
||||
continue;
|
||||
if (atomic_read(&skb_shinfo(f->skb)->dataref) == 1) {
|
||||
skb_shinfo(f->skb)->nr_frags = f->skb->data_len = 0;
|
||||
return f;
|
||||
}
|
||||
n++;
|
||||
}
|
||||
if (n == d->nframes) /* wait for network layer */
|
||||
d->flags |= DEVFL_KICKME;
|
||||
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* enters with d->lock held */
|
||||
void
|
||||
aoecmd_work(struct aoedev *d)
|
||||
|
@ -239,7 +264,7 @@ aoecmd_work(struct aoedev *d)
|
|||
}
|
||||
|
||||
loop:
|
||||
f = getframe(d, FREETAG);
|
||||
f = freeframe(d);
|
||||
if (f == NULL)
|
||||
return;
|
||||
if (d->inprocess == NULL) {
|
||||
|
@ -282,20 +307,25 @@ rexmit(struct aoedev *d, struct frame *f)
|
|||
n = DEFAULTBCNT / 512;
|
||||
if (ah->scnt > n) {
|
||||
ah->scnt = n;
|
||||
if (ah->aflags & AOEAFL_WRITE)
|
||||
if (ah->aflags & AOEAFL_WRITE) {
|
||||
skb_fill_page_desc(skb, 0, virt_to_page(f->bufaddr),
|
||||
offset_in_page(f->bufaddr), DEFAULTBCNT);
|
||||
skb->len = sizeof *h + sizeof *ah + DEFAULTBCNT;
|
||||
skb->data_len = DEFAULTBCNT;
|
||||
}
|
||||
if (++d->lostjumbo > (d->nframes << 1))
|
||||
if (d->maxbcnt != DEFAULTBCNT) {
|
||||
iprintk("too many lost jumbo - using 1KB frames.\n");
|
||||
iprintk("e%ld.%ld: too many lost jumbo on %s - using 1KB frames.\n",
|
||||
d->aoemajor, d->aoeminor, d->ifp->name);
|
||||
d->maxbcnt = DEFAULTBCNT;
|
||||
d->flags |= DEVFL_MAXBCNT;
|
||||
}
|
||||
}
|
||||
|
||||
skb->dev = d->ifp;
|
||||
skb_get(skb);
|
||||
skb->next = NULL;
|
||||
skb = skb_clone(skb, GFP_ATOMIC);
|
||||
if (skb == NULL)
|
||||
return;
|
||||
if (d->sendq_hd)
|
||||
d->sendq_tl->next = skb;
|
||||
else
|
||||
|
@ -350,6 +380,10 @@ rexmit_timer(ulong vp)
|
|||
rexmit(d, f);
|
||||
}
|
||||
}
|
||||
if (d->flags & DEVFL_KICKME) {
|
||||
d->flags &= ~DEVFL_KICKME;
|
||||
aoecmd_work(d);
|
||||
}
|
||||
|
||||
sl = d->sendq_hd;
|
||||
d->sendq_hd = d->sendq_tl = NULL;
|
||||
|
@ -552,23 +586,27 @@ aoecmd_ata_rsp(struct sk_buff *skb)
|
|||
case WIN_WRITE:
|
||||
case WIN_WRITE_EXT:
|
||||
if (f->bcnt -= n) {
|
||||
skb = f->skb;
|
||||
f->bufaddr += n;
|
||||
put_lba(ahout, f->lba += ahout->scnt);
|
||||
n = f->bcnt;
|
||||
if (n > DEFAULTBCNT)
|
||||
n = DEFAULTBCNT;
|
||||
ahout->scnt = n >> 9;
|
||||
if (ahout->aflags & AOEAFL_WRITE)
|
||||
skb_fill_page_desc(f->skb, 0,
|
||||
if (ahout->aflags & AOEAFL_WRITE) {
|
||||
skb_fill_page_desc(skb, 0,
|
||||
virt_to_page(f->bufaddr),
|
||||
offset_in_page(f->bufaddr), n);
|
||||
skb->len = sizeof *hout + sizeof *ahout + n;
|
||||
skb->data_len = n;
|
||||
}
|
||||
f->tag = newtag(d);
|
||||
hout->tag = cpu_to_be32(f->tag);
|
||||
skb->dev = d->ifp;
|
||||
skb_get(f->skb);
|
||||
f->skb->next = NULL;
|
||||
skb = skb_clone(skb, GFP_ATOMIC);
|
||||
spin_unlock_irqrestore(&d->lock, flags);
|
||||
aoenet_xmit(f->skb);
|
||||
if (skb)
|
||||
aoenet_xmit(skb);
|
||||
return;
|
||||
}
|
||||
if (n > DEFAULTBCNT)
|
||||
|
@ -642,7 +680,7 @@ aoecmd_ata_id(struct aoedev *d)
|
|||
struct frame *f;
|
||||
struct sk_buff *skb;
|
||||
|
||||
f = getframe(d, FREETAG);
|
||||
f = freeframe(d);
|
||||
if (f == NULL) {
|
||||
eprintk("can't get a frame. This shouldn't happen.\n");
|
||||
return NULL;
|
||||
|
@ -652,8 +690,8 @@ aoecmd_ata_id(struct aoedev *d)
|
|||
skb = f->skb;
|
||||
h = (struct aoe_hdr *) skb->mac.raw;
|
||||
ah = (struct aoe_atahdr *) (h+1);
|
||||
skb->len = sizeof *h + sizeof *ah;
|
||||
memset(h, 0, skb->len);
|
||||
skb->len = ETH_ZLEN;
|
||||
memset(h, 0, ETH_ZLEN);
|
||||
f->tag = aoehdr_atainit(d, h);
|
||||
f->waited = 0;
|
||||
|
||||
|
@ -663,12 +701,11 @@ aoecmd_ata_id(struct aoedev *d)
|
|||
ah->lba3 = 0xa0;
|
||||
|
||||
skb->dev = d->ifp;
|
||||
skb_get(skb);
|
||||
|
||||
d->rttavg = MAXTIMER;
|
||||
d->timer.function = rexmit_timer;
|
||||
|
||||
return skb;
|
||||
return skb_clone(skb, GFP_ATOMIC);
|
||||
}
|
||||
|
||||
void
|
||||
|
@ -724,7 +761,12 @@ aoecmd_cfg_rsp(struct sk_buff *skb)
|
|||
n /= 512;
|
||||
if (n > ch->scnt)
|
||||
n = ch->scnt;
|
||||
d->maxbcnt = n ? n * 512 : DEFAULTBCNT;
|
||||
n = n ? n * 512 : DEFAULTBCNT;
|
||||
if (n != d->maxbcnt) {
|
||||
iprintk("e%ld.%ld: setting %d byte data frames on %s\n",
|
||||
d->aoemajor, d->aoeminor, n, d->ifp->name);
|
||||
d->maxbcnt = n;
|
||||
}
|
||||
}
|
||||
|
||||
/* don't change users' perspective */
|
||||
|
|
|
@ -121,6 +121,7 @@ aoedev_downdev(struct aoedev *d)
|
|||
mempool_free(buf, d->bufpool);
|
||||
bio_endio(bio, bio->bi_size, -EIO);
|
||||
}
|
||||
skb_shinfo(f->skb)->nr_frags = f->skb->data_len = 0;
|
||||
}
|
||||
d->inprocess = NULL;
|
||||
|
||||
|
|
Loading…
Reference in a new issue