2007-01-06 02:30:30

by Chris Wright

[permalink] [raw]
Subject: [patch 22/50] fix aoe without scatter-gather [Bug 7662]

-stable review patch. If anyone has any objections, please let us know.
------------------

From: Ed L Cashin <[email protected]>

Fix a bug that only appears when AoE goes over a network card that does not
support scatter-gather. The headers in the linear part of the skb appeared
to be larger than they really were, resulting in data that was offset by 24
bytes.

This patch eliminates the offset data on cards that don't support
scatter-gather or have had scatter-gather turned off. There remains an
unrelated issue that I'll address in a separate email.

Fixes bugzilla #7662

Signed-off-by: "Ed L. Cashin" <[email protected]>
Cc: <[email protected]>
Cc: Greg KH <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Chris Wright <[email protected]>
---

drivers/block/aoe/aoecmd.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)

--- linux-2.6.19.1.orig/drivers/block/aoe/aoecmd.c
+++ linux-2.6.19.1/drivers/block/aoe/aoecmd.c
@@ -30,8 +30,6 @@ new_skb(ulong len)
skb->nh.raw = skb->mac.raw = skb->data;
skb->protocol = __constant_htons(ETH_P_AOE);
skb->priority = 0;
- skb_put(skb, len);
- memset(skb->head, 0, len);
skb->next = skb->prev = NULL;

/* tell the network layer not to perform IP checksums
@@ -122,8 +120,8 @@ aoecmd_ata_rw(struct aoedev *d, struct f
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, ETH_ZLEN);
+ skb_put(skb, sizeof *h + sizeof *ah);
+ memset(h, 0, skb->len);
f->tag = aoehdr_atainit(d, h);
f->waited = 0;
f->buf = buf;
@@ -149,7 +147,6 @@ aoecmd_ata_rw(struct aoedev *d, struct f
skb->len += bcnt;
skb->data_len = bcnt;
} else {
- skb->len = ETH_ZLEN;
writebit = 0;
}

@@ -206,6 +203,7 @@ aoecmd_cfg_pkts(ushort aoemajor, unsigne
printk(KERN_INFO "aoe: skb alloc failure\n");
continue;
}
+ skb_put(skb, sizeof *h + sizeof *ch);
skb->dev = ifp;
if (sl_tail == NULL)
sl_tail = skb;
@@ -243,6 +241,7 @@ freeframe(struct aoedev *d)
continue;
if (atomic_read(&skb_shinfo(f->skb)->dataref) == 1) {
skb_shinfo(f->skb)->nr_frags = f->skb->data_len = 0;
+ skb_trim(f->skb, 0);
return f;
}
n++;
@@ -698,8 +697,8 @@ aoecmd_ata_id(struct aoedev *d)
skb = f->skb;
h = (struct aoe_hdr *) skb->mac.raw;
ah = (struct aoe_atahdr *) (h+1);
- skb->len = ETH_ZLEN;
- memset(h, 0, ETH_ZLEN);
+ skb_put(skb, sizeof *h + sizeof *ah);
+ memset(h, 0, skb->len);
f->tag = aoehdr_atainit(d, h);
f->waited = 0;


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