Commit 4f51dc5e authored by Ed L. Cashin's avatar Ed L. Cashin Committed by Greg Kroah-Hartman
Browse files

aoe: zero copy write 2 of 2



Avoid memory copy on writes.
(This patch follows patch 4.)

Signed-off-by: default avatar"Ed L. Cashin" <ecashin@coraid.com>
Acked-by: default avatarAlan Cox <alan@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent dced3a05
......@@ -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;
......
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment