kvm tools: Introduce ethernet frame buffer system for uip

- uip_buf_get_free()
  Get a free buffer from buffer pool, sleep if there is no free buffer.

- uip_buf_get_used()
  Get a used buffer from buffer pool, sleep if there is no used buffer.

- uip_buf_set_free()
  Set a buffer as free, so it can be reused by the buffer producer.

- uip_buf_set_used()
  Set a buffer as used, uip rx code will inject the ethernet frame in
  this buffer into guest.

- uip_buf_clone()
  Get a free buffer, and clone data into it.

Signed-off-by: Asias He <asias.hejun@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

diff --git a/tools/kvm/Makefile b/tools/kvm/Makefile
index d368c2216b0afb3f50739c989bfb975b781088c7..91539de76234bde1091753d30c17caaede2f6101 100644 (file)
--- a/tools/kvm/Makefile
+++ b/tools/kvm/Makefile
@@ -45,6 +45,7 @@ OBJS  += disk/qcow.o
 OBJS   += disk/raw.o
 OBJS   += ioeventfd.o
 OBJS   += irq.o
+OBJS   += uip/buf.o
 OBJS   += kvm-cmd.o
 OBJS   += kvm-debug.o
 OBJS   += kvm-help.o

diff --git a/tools/kvm/include/kvm/uip.h b/tools/kvm/include/kvm/uip.h
new file mode 100644 (file)
index 0000000..32a5da3
--- /dev/null
+++ b/tools/kvm/include/kvm/uip.h
@@ -0,0 +1,69 @@
+#ifndef KVM__UIP_H
+#define KVM__UIP_H
+
+#include "linux/types.h"
+#include "kvm/mutex.h"
+
+#include <netinet/in.h>
+#include <sys/uio.h>
+
+#define UIP_BUF_STATUS_FREE    0
+#define UIP_BUF_STATUS_INUSE   1
+#define UIP_BUF_STATUS_USED    2
+
+struct uip_eth_addr {
+       u8 addr[6];
+};
+
+struct uip_eth {
+       struct uip_eth_addr dst;
+       struct uip_eth_addr src;
+       u16 type;
+} __attribute__((packed));
+
+struct uip_info {
+       struct list_head udp_socket_head;
+       struct list_head tcp_socket_head;
+       pthread_mutex_t udp_socket_lock;
+       pthread_mutex_t tcp_socket_lock;
+       struct uip_eth_addr guest_mac;
+       struct uip_eth_addr host_mac;
+       pthread_cond_t buf_free_cond;
+       pthread_cond_t buf_used_cond;
+       struct list_head buf_head;
+       pthread_mutex_t buf_lock;
+       pthread_t udp_thread;
+       int udp_epollfd;
+       int buf_free_nr;
+       int buf_used_nr;
+       u32 host_ip;
+       u32 buf_nr;
+};
+
+struct uip_buf {
+       struct list_head list;
+       struct uip_info *info;
+       u32 payload;
+       int vnet_len;
+       int eth_len;
+       int status;
+       char *vnet;
+       char *eth;
+       int id;
+};
+
+struct uip_tx_arg {
+       struct virtio_net_hdr *vnet;
+       struct uip_info *info;
+       struct uip_eth *eth;
+       int vnet_len;
+       int eth_len;
+};
+
+struct uip_buf *uip_buf_set_used(struct uip_info *info, struct uip_buf *buf);
+struct uip_buf *uip_buf_set_free(struct uip_info *info, struct uip_buf *buf);
+struct uip_buf *uip_buf_get_used(struct uip_info *info);
+struct uip_buf *uip_buf_get_free(struct uip_info *info);
+struct uip_buf *uip_buf_clone(struct uip_tx_arg *arg);
+
+#endif /* KVM__UIP_H */

diff --git a/tools/kvm/uip/buf.c b/tools/kvm/uip/buf.c
new file mode 100644 (file)
index 0000000..5e564a9
--- /dev/null
+++ b/tools/kvm/uip/buf.c
@@ -0,0 +1,114 @@
+#include "kvm/uip.h"
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+
+struct uip_buf *uip_buf_get_used(struct uip_info *info)
+{
+       struct uip_buf *buf;
+       bool found = false;
+
+       mutex_lock(&info->buf_lock);
+
+       while (!(info->buf_used_nr > 0))
+               pthread_cond_wait(&info->buf_used_cond, &info->buf_lock);
+
+       list_for_each_entry(buf, &info->buf_head, list) {
+               if (buf->status == UIP_BUF_STATUS_USED) {
+                       /*
+                        * Set status to INUSE immediately to prevent
+                        * someone from using this buf until we free it
+                        */
+                       buf->status = UIP_BUF_STATUS_INUSE;
+                       info->buf_used_nr--;
+                       found = true;
+                       break;
+               }
+       }
+
+       mutex_unlock(&info->buf_lock);
+
+       return found ? buf : NULL;
+}
+
+struct uip_buf *uip_buf_get_free(struct uip_info *info)
+{
+       struct uip_buf *buf;
+       bool found = false;
+
+       mutex_lock(&info->buf_lock);
+
+       while (!(info->buf_free_nr > 0))
+               pthread_cond_wait(&info->buf_free_cond, &info->buf_lock);
+
+       list_for_each_entry(buf, &info->buf_head, list) {
+               if (buf->status == UIP_BUF_STATUS_FREE) {
+                       /*
+                        * Set status to INUSE immediately to prevent
+                        * someone from using this buf until we free it
+                        */
+                       buf->status = UIP_BUF_STATUS_INUSE;
+                       info->buf_free_nr--;
+                       found = true;
+                       break;
+               }
+       }
+
+       mutex_unlock(&info->buf_lock);
+
+       return found ? buf : NULL;
+}
+
+struct uip_buf *uip_buf_set_used(struct uip_info *info, struct uip_buf *buf)
+{
+       mutex_lock(&info->buf_lock);
+
+       buf->status = UIP_BUF_STATUS_USED;
+       info->buf_used_nr++;
+       pthread_cond_signal(&info->buf_used_cond);
+
+       mutex_unlock(&info->buf_lock);
+
+       return buf;
+}
+
+struct uip_buf *uip_buf_set_free(struct uip_info *info, struct uip_buf *buf)
+{
+       mutex_lock(&info->buf_lock);
+
+       buf->status = UIP_BUF_STATUS_FREE;
+       info->buf_free_nr++;
+       pthread_cond_signal(&info->buf_free_cond);
+
+       mutex_unlock(&info->buf_lock);
+
+       return buf;
+}
+
+struct uip_buf *uip_buf_clone(struct uip_tx_arg *arg)
+{
+       struct uip_buf *buf;
+       struct uip_eth *eth2;
+       struct uip_info *info;
+
+       info = arg->info;
+
+       /*
+        * Get buffer from device to guest
+        */
+       buf = uip_buf_get_free(info);
+
+       /*
+        * Clone buffer
+        */
+       memcpy(buf->vnet, arg->vnet, arg->vnet_len);
+       memcpy(buf->eth, arg->eth, arg->eth_len);
+       buf->vnet_len   = arg->vnet_len;
+       buf->eth_len    = arg->eth_len;
+
+       eth2            = (struct uip_eth *)buf->eth;
+       eth2->src       = info->host_mac;
+       eth2->dst       = arg->eth->src;
+
+       return buf;
+}