/*
* 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 Software 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.
*/
#ifndef __XEN_NETBACK__COMMON_H__
#define __XEN_NETBACK__COMMON_H__
#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/ip.h>
#include <linux/in.h>
#include <linux/io.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <xen/interface/io/netif.h>
#include <xen/interface/grant_table.h>
#include <xen/grant_table.h>
#include <xen/xenbus.h>
typedef unsigned int pending_ring_idx_t;
#define INVALID_PENDING_RING_IDX (~0U)
/* For the head field in pending_tx_info: it is used to indicate
* whether this tx info is the head of one or more coalesced requests.
*
* When head != INVALID_PENDING_RING_IDX, it means the start of a new
* tx requests queue and the end of previous queue.
*
* An example sequence of head fields (I = INVALID_PENDING_RING_IDX):
*
* ...|0 I I I|5 I|9 I I I|...
* -->|<-INUSE----------------
*
* After consuming the first slot(s) we have:
*
* ...|V V V V|5 I|9 I I I|...
* -----FREE->|<-INUSE--------
*
* where V stands for "valid pending ring index". Any number other
* than INVALID_PENDING_RING_IDX is OK. These entries are considered
* free and can contain any number other than
* INVALID_PENDING_RING_IDX. In practice we use 0.
*
* The in use non-INVALID_PENDING_RING_IDX (say 0, 5 and 9 in the
* above example) number is the index into pending_tx_info and
* mmap_pages arrays.
*/
struct pending_tx_info {
struct xen_netif_tx_request req; /* coalesced tx request */
pending_ring_idx_t head; /* head != INVALID_PENDING_RING_IDX
* if it is head of one or more tx
* reqs
*/
};
#define XEN_NETIF_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE)
#define XEN_NETIF_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE)
struct xenvif_rx_meta {
int id;
int size;
int gso_type;
int gso_size;
};
#define GSO_BIT(type) \
(1 << XEN_NETIF_GSO_TYPE_ ## type)
/* Discriminate from any valid pending_idx value. */
#define INVALID_PENDING_IDX 0xFFFF
#define MAX_BUFFER_OFFSET PAGE_SIZE
#define MAX_PENDING_REQS 256
/* It's possible for an skb to have a maximal number of frags
* but still be less than MAX_BUFFER_OFFSET in size. Thus the
* worst-case number of copy operations is MAX_SKB_FRAGS per
* ring slot.
*/
#define MAX_GRANT_COPY_OPS (MAX_SKB_FRAGS * XEN_NETIF_RX_RING_SIZE)
struct xenvif {
/* Unique identifier for this interface. */
domid_t domid;
unsigned int handle;
/* Use NAPI for guest TX */
struct napi_struct napi;
/* When feature-split-event-channels = 0, tx_irq = rx_irq. */
unsigned int tx_irq;
/* Only used when feature-split-event-channels = 1 */
char tx_irq_name[IFNAMSIZ+4]; /* DEVNAME-tx */
struct xen_netif_tx_back_ring tx;
struct sk_buff_head tx_queue;
struct page *mmap_pages[MAX_PENDING_REQS];
pending_ring_idx_t pending_prod;
pending_ring_idx_t pending_cons;
u16 pending_ring[MAX_PENDING_REQS];
struct pending_tx_info pending_tx_info[MAX_PENDING_REQS];
/* Coalescing tx requests before copying makes number of grant
* copy ops greater or equal to number of slots required. In
* worst case a tx request consumes 2 gnttab_copy.
*/
struct gnttab_copy tx_copy_ops[2*MAX_PENDING_REQS];
/* Use kthread for guest RX */
struct task_struct *task;
wait_queue_head_t wq;
/* When feature-split-event-channels = 0, tx_irq = rx_irq. */
unsigned int rx_irq;
/* Only used when feature-split-event-channels = 1 */
char rx_irq_name[IFNAMSIZ+4]; /* DEVNAME-rx */
struct xen_netif_rx_back_ring rx;
struct sk_buff_head rx_queue;
/* Allow xenvif_start_xmit() to peek ahead in the rx request
* ring. This is a prediction of what rx_req_cons will be
* once all queued skbs are put on the ring.
*/
RING_IDX rx_req_cons_peek;
/* This array is allocated seperately as it is large */
struct gnttab_copy *grant_copy_op;
/* We create one meta structure per ring request we consume, so
* the maximum number is the same as the ring size.
*/
struct xenvif_rx_meta meta[XEN_NETIF_RX_RING_SIZE];
u8 fe_dev_addr[6];
/* Frontend feature information. */
int gso_mask;
int gso_prefix_mask;
u8 can_sg:1;
u8 ip_csum:1;
u8 ipv6_csum:1;
/* Internal feature information. */
u8 can_queue:1; /* can queue packets for receiver? */
/* Transmit shaping: allow 'credit_bytes' every 'credit_usec'. */
unsigned long credit_bytes;
unsigned long credit_usec;
unsigned long remaining_credit;
struct timer_list credit_timeout;
u64 credit_window_start;
/* Statistics */
unsigned long rx_gso_checksum_fixup;
/* Miscellaneous private stuff. */
struct net_device *dev;
};
static inline struct xenbus_device *xenvif_to_xenbus_device(struct xenvif *vif)
{
return to_xenbus_device(vif->dev->dev.parent);
}
struct xenvif *xenvif_alloc(struct device *parent,
domid_t domid,
unsigned int handle);
int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
unsigned long rx_ring_ref, unsigned int tx_evtchn,
unsigned int rx_evtchn);
void xenvif_disconnect(struct xenvif *vif);
void xenvif_free(struct xenvif *vif);
int xenvif_xenbus_init(void);
void xenvif_xenbus_fini(void);
int xenvif_schedulable(struct xenvif *vif);
int xenvif_rx_ring_full(struct xenvif *vif);
int xenvif_must_stop_queue(struct xenvif *vif);
/* (Un)Map communication rings. */
void xenvif_unmap_frontend_rings(struct xenvif *vif);
int xenvif_map_frontend_rings(struct xenvif *vif,
grant_ref_t tx_ring_ref,
grant_ref_t rx_ring_ref);
/* Check for SKBs from frontend and schedule backend processing */
void xenvif_check_rx_xenvif(struct xenvif *vif);
/* Queue an SKB for transmission to the frontend */
void xenvif_queue_tx_skb(struct xenvif *vif, struct sk_buff *skb);
/* Notify xenvif that ring now has space to send an skb to the frontend */
void xenvif_notify_tx_completion(struct xenvif *vif);
/* Prevent the device from generating any further traffic. */
void xenvif_carrier_off(struct xenvif *vif);
/* Returns number of ring slots required to send an skb to the frontend */
unsigned int xenvif_count_skb_slots(struct xenvif *vif, struct sk_buff *skb);
int xenvif_tx_action(struct xenvif *vif, int budget);
void xenvif_rx_action(struct xenvif *vif);
int xenvif_kthread(void *data);
extern bool separate_tx_rx_irq;
#endif /* __XEN_NETBACK__COMMON_H__ */
