xen-netback: add control protocol implementation
[linux-2.6-microblaze.git] / drivers / net / xen-netback / hash.c
diff --git a/drivers/net/xen-netback/hash.c b/drivers/net/xen-netback/hash.c
new file mode 100644 (file)
index 0000000..392e392
--- /dev/null
@@ -0,0 +1,384 @@
+/*
+ * Copyright (c) 2016 Citrix Systems Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Softare Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#define XEN_NETIF_DEFINE_TOEPLITZ
+
+#include "common.h"
+#include <linux/vmalloc.h>
+#include <linux/rculist.h>
+
+static void xenvif_del_hash(struct rcu_head *rcu)
+{
+       struct xenvif_hash_cache_entry *entry;
+
+       entry = container_of(rcu, struct xenvif_hash_cache_entry, rcu);
+
+       kfree(entry);
+}
+
+static void xenvif_add_hash(struct xenvif *vif, const u8 *tag,
+                           unsigned int len, u32 val)
+{
+       struct xenvif_hash_cache_entry *new, *entry, *oldest;
+       unsigned long flags;
+       bool found;
+
+       new = kmalloc(sizeof(*entry), GFP_KERNEL);
+       if (!new)
+               return;
+
+       memcpy(new->tag, tag, len);
+       new->len = len;
+       new->val = val;
+
+       spin_lock_irqsave(&vif->hash.cache.lock, flags);
+
+       found = false;
+       oldest = NULL;
+       list_for_each_entry_rcu(entry, &vif->hash.cache.list, link) {
+               /* Make sure we don't add duplicate entries */
+               if (entry->len == len &&
+                   memcmp(entry->tag, tag, len) == 0)
+                       found = true;
+               if (!oldest || entry->seq < oldest->seq)
+                       oldest = entry;
+       }
+
+       if (!found) {
+               new->seq = atomic_inc_return(&vif->hash.cache.seq);
+               list_add_rcu(&new->link, &vif->hash.cache.list);
+
+               if (++vif->hash.cache.count > xenvif_hash_cache_size) {
+                       list_del_rcu(&oldest->link);
+                       vif->hash.cache.count--;
+                       call_rcu(&oldest->rcu, xenvif_del_hash);
+               }
+       }
+
+       spin_unlock_irqrestore(&vif->hash.cache.lock, flags);
+
+       if (found)
+               kfree(new);
+}
+
+static u32 xenvif_new_hash(struct xenvif *vif, const u8 *data,
+                          unsigned int len)
+{
+       u32 val;
+
+       val = xen_netif_toeplitz_hash(vif->hash.key,
+                                     sizeof(vif->hash.key),
+                                     data, len);
+
+       if (xenvif_hash_cache_size != 0)
+               xenvif_add_hash(vif, data, len, val);
+
+       return val;
+}
+
+static void xenvif_flush_hash(struct xenvif *vif)
+{
+       struct xenvif_hash_cache_entry *entry;
+       unsigned long flags;
+
+       if (xenvif_hash_cache_size == 0)
+               return;
+
+       spin_lock_irqsave(&vif->hash.cache.lock, flags);
+
+       list_for_each_entry_rcu(entry, &vif->hash.cache.list, link) {
+               list_del_rcu(&entry->link);
+               vif->hash.cache.count--;
+               call_rcu(&entry->rcu, xenvif_del_hash);
+       }
+
+       spin_unlock_irqrestore(&vif->hash.cache.lock, flags);
+}
+
+static u32 xenvif_find_hash(struct xenvif *vif, const u8 *data,
+                           unsigned int len)
+{
+       struct xenvif_hash_cache_entry *entry;
+       u32 val;
+       bool found;
+
+       if (len >= XEN_NETBK_HASH_TAG_SIZE)
+               return 0;
+
+       if (xenvif_hash_cache_size == 0)
+               return xenvif_new_hash(vif, data, len);
+
+       rcu_read_lock();
+
+       found = false;
+
+       list_for_each_entry_rcu(entry, &vif->hash.cache.list, link) {
+               if (entry->len == len &&
+                   memcmp(entry->tag, data, len) == 0) {
+                       val = entry->val;
+                       entry->seq = atomic_inc_return(&vif->hash.cache.seq);
+                       found = true;
+                       break;
+               }
+       }
+
+       rcu_read_unlock();
+
+       if (!found)
+               val = xenvif_new_hash(vif, data, len);
+
+       return val;
+}
+
+void xenvif_set_skb_hash(struct xenvif *vif, struct sk_buff *skb)
+{
+       struct flow_keys flow;
+       u32 hash = 0;
+       enum pkt_hash_types type = PKT_HASH_TYPE_NONE;
+       u32 flags = vif->hash.flags;
+       bool has_tcp_hdr;
+
+       /* Quick rejection test: If the network protocol doesn't
+        * correspond to any enabled hash type then there's no point
+        * in parsing the packet header.
+        */
+       switch (skb->protocol) {
+       case htons(ETH_P_IP):
+               if (flags & (XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP |
+                            XEN_NETIF_CTRL_HASH_TYPE_IPV4))
+                       break;
+
+               goto done;
+
+       case htons(ETH_P_IPV6):
+               if (flags & (XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP |
+                            XEN_NETIF_CTRL_HASH_TYPE_IPV6))
+                       break;
+
+               goto done;
+
+       default:
+               goto done;
+       }
+
+       memset(&flow, 0, sizeof(flow));
+       if (!skb_flow_dissect_flow_keys(skb, &flow, 0))
+               goto done;
+
+       has_tcp_hdr = (flow.basic.ip_proto == IPPROTO_TCP) &&
+                     !(flow.control.flags & FLOW_DIS_IS_FRAGMENT);
+
+       switch (skb->protocol) {
+       case htons(ETH_P_IP):
+               if (has_tcp_hdr &&
+                   (flags & XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP)) {
+                       u8 data[12];
+
+                       memcpy(&data[0], &flow.addrs.v4addrs.src, 4);
+                       memcpy(&data[4], &flow.addrs.v4addrs.dst, 4);
+                       memcpy(&data[8], &flow.ports.src, 2);
+                       memcpy(&data[10], &flow.ports.dst, 2);
+
+                       hash = xenvif_find_hash(vif, data, sizeof(data));
+                       type = PKT_HASH_TYPE_L4;
+               } else if (flags & XEN_NETIF_CTRL_HASH_TYPE_IPV4) {
+                       u8 data[8];
+
+                       memcpy(&data[0], &flow.addrs.v4addrs.src, 4);
+                       memcpy(&data[4], &flow.addrs.v4addrs.dst, 4);
+
+                       hash = xenvif_find_hash(vif, data, sizeof(data));
+                       type = PKT_HASH_TYPE_L3;
+               }
+
+               break;
+
+       case htons(ETH_P_IPV6):
+               if (has_tcp_hdr &&
+                   (flags & XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP)) {
+                       u8 data[36];
+
+                       memcpy(&data[0], &flow.addrs.v6addrs.src, 16);
+                       memcpy(&data[16], &flow.addrs.v6addrs.dst, 16);
+                       memcpy(&data[32], &flow.ports.src, 2);
+                       memcpy(&data[34], &flow.ports.dst, 2);
+
+                       hash = xenvif_find_hash(vif, data, sizeof(data));
+                       type = PKT_HASH_TYPE_L4;
+               } else if (flags & XEN_NETIF_CTRL_HASH_TYPE_IPV6) {
+                       u8 data[32];
+
+                       memcpy(&data[0], &flow.addrs.v6addrs.src, 16);
+                       memcpy(&data[16], &flow.addrs.v6addrs.dst, 16);
+
+                       hash = xenvif_find_hash(vif, data, sizeof(data));
+                       type = PKT_HASH_TYPE_L3;
+               }
+
+               break;
+       }
+
+done:
+       if (type == PKT_HASH_TYPE_NONE)
+               skb_clear_hash(skb);
+       else
+               __skb_set_sw_hash(skb, hash, type == PKT_HASH_TYPE_L4);
+}
+
+u32 xenvif_set_hash_alg(struct xenvif *vif, u32 alg)
+{
+       switch (alg) {
+       case XEN_NETIF_CTRL_HASH_ALGORITHM_NONE:
+       case XEN_NETIF_CTRL_HASH_ALGORITHM_TOEPLITZ:
+               break;
+
+       default:
+               return XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER;
+       }
+
+       vif->hash.alg = alg;
+
+       return XEN_NETIF_CTRL_STATUS_SUCCESS;
+}
+
+u32 xenvif_get_hash_flags(struct xenvif *vif, u32 *flags)
+{
+       if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE)
+               return XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED;
+
+       *flags = XEN_NETIF_CTRL_HASH_TYPE_IPV4 |
+                XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP |
+                XEN_NETIF_CTRL_HASH_TYPE_IPV6 |
+                XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP;
+
+       return XEN_NETIF_CTRL_STATUS_SUCCESS;
+}
+
+u32 xenvif_set_hash_flags(struct xenvif *vif, u32 flags)
+{
+       if (flags & ~(XEN_NETIF_CTRL_HASH_TYPE_IPV4 |
+                     XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP |
+                     XEN_NETIF_CTRL_HASH_TYPE_IPV6 |
+                     XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP))
+               return XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER;
+
+       if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE)
+               return XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER;
+
+       vif->hash.flags = flags;
+
+       return XEN_NETIF_CTRL_STATUS_SUCCESS;
+}
+
+u32 xenvif_set_hash_key(struct xenvif *vif, u32 gref, u32 len)
+{
+       u8 *key = vif->hash.key;
+       struct gnttab_copy copy_op = {
+               .source.u.ref = gref,
+               .source.domid = vif->domid,
+               .dest.u.gmfn = virt_to_gfn(key),
+               .dest.domid = DOMID_SELF,
+               .dest.offset = xen_offset_in_page(key),
+               .len = len,
+               .flags = GNTCOPY_source_gref
+       };
+
+       if (len > XEN_NETBK_MAX_HASH_KEY_SIZE)
+               return XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER;
+
+       if (len != 0) {
+               gnttab_batch_copy(&copy_op, 1);
+
+               if (copy_op.status != GNTST_okay)
+                       return XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER;
+       }
+
+       /* Clear any remaining key octets */
+       if (len < XEN_NETBK_MAX_HASH_KEY_SIZE)
+               memset(key + len, 0, XEN_NETBK_MAX_HASH_KEY_SIZE - len);
+
+       xenvif_flush_hash(vif);
+
+       return XEN_NETIF_CTRL_STATUS_SUCCESS;
+}
+
+u32 xenvif_set_hash_mapping_size(struct xenvif *vif, u32 size)
+{
+       if (size > XEN_NETBK_MAX_HASH_MAPPING_SIZE)
+               return XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER;
+
+       vif->hash.size = size;
+       memset(vif->hash.mapping, 0, sizeof(u32) * size);
+
+       return XEN_NETIF_CTRL_STATUS_SUCCESS;
+}
+
+u32 xenvif_set_hash_mapping(struct xenvif *vif, u32 gref, u32 len,
+                           u32 off)
+{
+       u32 *mapping = &vif->hash.mapping[off];
+       struct gnttab_copy copy_op = {
+               .source.u.ref = gref,
+               .source.domid = vif->domid,
+               .dest.u.gmfn = virt_to_gfn(mapping),
+               .dest.domid = DOMID_SELF,
+               .dest.offset = xen_offset_in_page(mapping),
+               .len = len * sizeof(u32),
+               .flags = GNTCOPY_source_gref
+       };
+
+       if ((off + len > vif->hash.size) || copy_op.len > XEN_PAGE_SIZE)
+               return XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER;
+
+       while (len-- != 0)
+               if (mapping[off++] >= vif->num_queues)
+                       return XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER;
+
+       if (len != 0) {
+               gnttab_batch_copy(&copy_op, 1);
+
+               if (copy_op.status != GNTST_okay)
+                       return XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER;
+       }
+
+       return XEN_NETIF_CTRL_STATUS_SUCCESS;
+}
+
+void xenvif_init_hash(struct xenvif *vif)
+{
+       if (xenvif_hash_cache_size == 0)
+               return;
+
+       spin_lock_init(&vif->hash.cache.lock);
+       INIT_LIST_HEAD(&vif->hash.cache.list);
+}
+
+void xenvif_deinit_hash(struct xenvif *vif)
+{
+       xenvif_flush_hash(vif);
+}