1 files changed, 83 insertions, 34 deletions

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index 1be5150bcd3b..b49e06ef121e 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -106,45 +106,104 @@ ifrotate(struct aoetgt *t)
         }
 }
 
+static void
+skb_pool_put(struct aoedev *d, struct sk_buff *skb)
+{
+        if (!d->skbpool_hd)
+                d->skbpool_hd = skb;
+        else
+                d->skbpool_tl->next = skb;
+        d->skbpool_tl = skb;
+}
+
+static struct sk_buff *
+skb_pool_get(struct aoedev *d)
+{
+        struct sk_buff *skb;
+
+        skb = d->skbpool_hd;
+        if (skb && atomic_read(&skb_shinfo(skb)->dataref) == 1) {
+                d->skbpool_hd = skb->next;
+                skb->next = NULL;
+                return skb;
+        }
+        if (d->nskbpool < NSKBPOOLMAX
+        && (skb = new_skb(ETH_ZLEN))) {
+                d->nskbpool++;
+                return skb;
+        }
+        return NULL;
+}
+
+/* freeframe is where we do our load balancing so it's a little hairy. */
 static struct frame *
 freeframe(struct aoedev *d)
 {
-        struct frame *f, *e;
+        struct frame *f, *e, *rf;
         struct aoetgt **t;
-        ulong n;
+        struct sk_buff *skb;
 
         if (d->targets[0] == NULL) {    /* shouldn't happen, but I'm paranoid */
                 printk(KERN_ERR "aoe: NULL TARGETS!\n");
                 return NULL;
         }
-        t = d->targets;
-        do {
-                if (t != d->htgt
-                && (*t)->ifp->nd
-                && (*t)->nout < (*t)->maxout) {
-                        n = (*t)->nframes;
+        t = d->tgt;
+        t++;
+        if (t >= &d->targets[NTARGETS] || !*t)
+                t = d->targets;
+        for (;;) {
+                if ((*t)->nout < (*t)->maxout
+                && t != d->htgt
+                && (*t)->ifp->nd) {
+                        rf = NULL;
                         f = (*t)->frames;
-                        e = f + n;
+                        e = f + (*t)->nframes;
                         for (; f < e; f++) {
                                 if (f->tag != FREETAG)
                                         continue;
-                                if (atomic_read(&skb_shinfo(f->skb)->dataref)
+                                skb = f->skb;
+                                if (!skb
+                                && !(f->skb = skb = new_skb(ETH_ZLEN)))
+                                        continue;
+                                if (atomic_read(&skb_shinfo(skb)->dataref)
                                         != 1) {
-                                        n--;
+                                        if (!rf)
+                                                rf = f;
                                         continue;
                                 }
-                                skb_shinfo(f->skb)->nr_frags = 0;
-                                f->skb->data_len = 0;
-                                skb_trim(f->skb, 0);
+gotone:                         skb_shinfo(skb)->nr_frags = skb->data_len = 0;
+                                skb_trim(skb, 0);
                                 d->tgt = t;
                                 ifrotate(*t);
                                 return f;
                         }
-                        if (n == 0)     /* slow polling network card */
+                        /* Work can be done, but the network layer is
+                           holding our precious packets.  Try to grab
+                           one from the pool. */
+                        f = rf;
+                        if (f == NULL) {        /* more paranoia */
+                                printk(KERN_ERR
+                                        "aoe: freeframe: %s.\n",
+                                        "unexpected null rf");
+                                d->flags |= DEVFL_KICKME;
+                                return NULL;
+                        }
+                        skb = skb_pool_get(d);
+                        if (skb) {
+                                skb_pool_put(d, f->skb);
+                                f->skb = skb;
+                                goto gotone;
+                        }
+                        (*t)->dataref++;
+                        if ((*t)->nout == 0)
                                 d->flags |= DEVFL_KICKME;
                 }
+                if (t == d->tgt)        /* we've looped and found nada */
+                        break;
                 t++;
-        } while (t < &d->targets[NTARGETS] && *t);
+                if (t >= &d->targets[NTARGETS] || !*t)
+                        t = d->targets;
+        }
         return NULL;
 }
 
@@ -894,33 +953,23 @@ addtgt(struct aoedev *d, char *addr, ulong nframes)
                 return NULL;
 
         t = kcalloc(1, sizeof *t, GFP_ATOMIC);
+        if (!t)
+                return NULL;
         f = kcalloc(nframes, sizeof *f, GFP_ATOMIC);
-        if (!t || !f)
-                goto bail;
+        if (!f) {
+                kfree(t);
+                return NULL;
+        }
+
         t->nframes = nframes;
         t->frames = f;
         e = f + nframes;
-        for (; f < e; f++) {
+        for (; f < e; f++)
                 f->tag = FREETAG;
-                f->skb = new_skb(ETH_ZLEN);
-                if (!f->skb)
-                        break;
-        }
-        if (f != e) {
-                while (f > t->frames) {
-                        f--;
-                        dev_kfree_skb(f->skb);
-                }
-                goto bail;
-        }
         memcpy(t->addr, addr, sizeof t->addr);
         t->ifp = t->ifs;
         t->maxout = t->nframes;
         return *tt = t;
-bail:
-        kfree(t);
-        kfree(f);
-        return NULL;
 }
 
 void