/*
* 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>
#include <xen/page.h>
#include <linux/debugfs.h>
typedef unsigned int pending_ring_idx_t;
struct pending_tx_info {
struct xen_netif_tx_request req; /* tx request */
unsigned int extra_count;
/* Callback data for released SKBs. The callback is always
* xenvif_zerocopy_callback, desc contains the pending_idx, which is
* also an index in pending_tx_info array. It is initialized in
* xenvif_alloc and it never changes.
* skb_shinfo(skb)->destructor_arg points to the first mapped slot's
* callback_struct in this array of struct pending_tx_info's, then ctx
* to the next, or NULL if there is no more slot for this skb.
* ubuf_to_vif is a helper which finds the struct xenvif from a pointer
* to this field.
*/
struct ubuf_info_msgzc callback_struct;
};
#define XEN_NETIF_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, XEN_PAGE_SIZE)
#define XEN_NETIF_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, XEN_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_PENDING_REQS XEN_NETIF_TX_RING_SIZE
/* The maximum number of frags is derived from the size of a grant (same
* as a Xen page size for now).
*/
#define MAX_XEN_SKB_FRAGS (65536 / XEN_PAGE_SIZE + 1)
#define NETBACK_INVALID_HANDLE -1
/* To avoid confusion, we define XEN_NETBK_LEGACY_SLOTS_MAX indicating
* the maximum slots a valid packet can use. Now this value is defined
* to be XEN_NETIF_NR_SLOTS_MIN, which is supposed to be supported by
* all backend.
*/
#define XEN_NETBK_LEGACY_SLOTS_MAX XEN_NETIF_NR_SLOTS_MIN
/* Queue name is interface name with "-qNNN" appended */
#define QUEUE_NAME_SIZE (IFNAMSIZ + 5)
/* IRQ name is queue name with "-tx" or "-rx" appended */
#define IRQ_NAME_SIZE (QUEUE_NAME_SIZE + 3)
struct xenvif;
struct xenvif_stats {
/* Stats fields to be updated per-queue.
* A subset of struct net_device_stats that contains only the
* fields that are updated in netback.c for each queue.
*/
u64 rx_bytes;
u64 rx_packets;
u64 tx_bytes;
u64 tx_packets;
/* Additional stats used by xenvif */
unsigned long rx_gso_checksum_fixup;
unsigned long tx_zerocopy_sent;
unsigned long tx_zerocopy_success;
unsigned long tx_zerocopy_fail;
unsigned long tx_frag_overflow;
};
#define COPY_BATCH_SIZE 64
struct xenvif_copy_state {
struct gnttab_copy op[COPY_BATCH_SIZE];
RING_IDX idx[COPY_BATCH_SIZE];
unsigned int num;
struct sk_buff_head *completed;
};
struct xenvif_queue { /* Per-queue data for xenvif */
unsigned int id; /* Queue ID, 0-based */
char name[QUEUE_NAME_SIZE]; /* DEVNAME-qN */
struct xenvif *vif; /* Parent VIF */
/*
* TX/RX common EOI handling.
* When feature-split-event-channels = 0, interrupt handler sets
* NETBK_COMMON_EOI, otherwise NETBK_RX_EOI and NETBK_TX_EOI are set
* by the RX and TX interrupt handlers.
* RX and TX handler threads will issue an EOI when either
* NETBK_COMMON_EOI or their specific bits (NETBK_RX_EOI or
* NETBK_TX_EOI) are set and they will reset those bits.
*/
atomic_t eoi_pending;
#define NETBK_RX_EOI 0x01
#define NETBK_TX_EOI 0x02
#define NETBK_COMMON_EOI 0x04
/* 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[IRQ_NAME_SIZE]; /* DEVNAME-qN-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];
grant_handle_t grant_tx_handle[MAX_PENDING_REQS];
struct gnttab_copy tx_copy_ops[2 * MAX_PENDING_REQS];
struct gnttab_map_grant_ref tx_map_ops[MAX_PENDING_REQS];
struct gnttab_unmap_grant_ref tx_unmap_ops[MAX_PENDING_REQS];
/* passed to gnttab_[un]map_refs with pages under (un)mapping */
struct page *pages_to_map[MAX_PENDING_REQS];
struct page *pages_to_unmap[MAX_PENDING_REQS];
/* This prevents zerocopy callbacks to race over dealloc_ring */
spinlock_t callback_lock;
/* This prevents dealloc thread and NAPI instance to race over response
* creation and pending_ring in xenvif_idx_release. In xenvif_tx_err
* it only protect response creation
*/
spinlock_t response_lock;
pending_ring_idx_t dealloc_prod;
pending_ring_idx_t dealloc_cons;
u16 dealloc_ring[MAX_PENDING_REQS];
struct task_struct *dealloc_task;
wait_queue_head_t dealloc_wq;
atomic_t inflight_packets;
/* 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[IRQ_NAME_SIZE]; /* DEVNAME-qN-rx */
struct xen_netif_rx_back_ring rx;
struct sk_buff_head rx_queue;
unsigned int rx_queue_max;
unsigned int rx_queue_len;
unsigned long last_rx_time;
unsigned int rx_slots_needed;
bool stalled;
struct xenvif_copy_state rx_copy;
/* 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;
bool rate_limited;
/* Statistics */
struct xenvif_stats stats;
};
enum state_bit_shift {
/* This bit marks that the vif is connected */
VIF_STATUS_CONNECTED,
};
struct xenvif_mcast_addr {
struct list_head entry;
struct rcu_head rcu;
u8 addr[6];
};
#define XEN_NETBK_MCAST_MAX 64
#define XEN_NETBK_MAX_HASH_KEY_SIZE 40
#define XEN_NETBK_MAX_HASH_MAPPING_SIZE 128
#define XEN_NETBK_HASH_TAG_SIZE 40
struct xenvif_hash_cache_entry {
struct list_head link;
struct rcu_head rcu;
u8 tag[XEN_NETBK_HASH_TAG_SIZE];
unsigned int len;
u32 val;
int seq;
};
struct xenvif_hash_cache {
spinlock_t lock;
struct list_head list;
unsigned int count;
atomic_t seq;
};
struct xenvif_hash {
unsigned int alg;
u32 flags;
bool mapping_sel;
u8 key[XEN_NETBK_MAX_HASH_KEY_SIZE];
u32 mapping[2][XEN_NETBK_MAX_HASH_MAPPING_SIZE];
unsigned int size;
struct xenvif_hash_cache cache;
};
struct backend_info {
struct xenbus_device *dev;
struct xenvif *vif;
/* This is the state that will be reflected in xenstore when any
* active hotplug script completes.
*/
enum xenbus_state state;
enum xenbus_state frontend_state;
struct xenbus_watch hotplug_status_watch;
u8 have_hotplug_status_watch:1;
const char *hotplug_script;
};
struct xenvif {
/* Unique identifier for this interface. */
domid_t domid;
unsigned int handle;
u8 fe_dev_addr[6];
struct list_head fe_mcast_addr;
unsigned int fe_mcast_count;
/* Frontend feature information. */
int gso_mask;
u8 can_sg:1;
u8 ip_csum:1;
u8 ipv6_csum:1;
u8 multicast_control:1;
/* headroom requested by xen-netfront */
u16 xdp_headroom;
/* Is this interface disabled? True when backend discovers
* frontend is rogue.
*/
bool disabled;
unsigned long status;
unsigned long drain_timeout;
unsigned long stall_timeout;
/* Queues */
struct xenvif_queue *queues;
unsigned int num_queues; /* active queues, resource allocated */
unsigned int stalled_queues;
struct xenvif_hash hash;
struct xenbus_watch credit_watch;
struct xenbus_watch mcast_ctrl_watch;
struct backend_info *be;
spinlock_t lock;
#ifdef CONFIG_DEBUG_FS
struct dentry *xenvif_dbg_root;
#endif
struct xen_netif_ctrl_back_ring ctrl;
unsigned int ctrl_irq;
/* Miscellaneous private stuff. */
struct net_device *dev;
};
struct xenvif_rx_cb {
unsigned long expires;
int meta_slots_used;
};
#define XENVIF_RX_CB(skb) ((struct xenvif_rx_cb *)(skb)->cb)
static inline struct xenbus_device *xenvif_to_xenbus_device(struct xenvif *vif)
{
return to_xenbus_device(vif->dev->dev.parent);
}
void xenvif_tx_credit_callback(struct timer_list *t);
struct xenvif *xenvif_alloc(struct device *parent,
domid_t domid,
unsigned int handle);
int xenvif_init_queue(struct xenvif_queue *queue);
void xenvif_deinit_queue(struct xenvif_queue *queue);
int xenvif_connect_data(struct xenvif_queue *queue,
unsigned long tx_ring_ref,
unsigned long rx_ring_ref,
unsigned int tx_evtchn,
unsigned int rx_evtchn);
void xenvif_disconnect_data(struct xenvif *vif);
int xenvif_connect_ctrl(struct xenvif *vif, grant_ref_t ring_ref,
unsigned int evtchn);
void xenvif_disconnect_ctrl(struct xenvif *vif);
void xenvif_free(struct xenvif *vif);
int xenvif_xenbus_init(void);
void xenvif_xenbus_fini(void);
/* (Un)Map communication rings. */
void xenvif_unmap_frontend_data_rings(struct xenvif_queue *queue);
int xenvif_map_frontend_data_rings(struct xenvif_queue *queue,
grant_ref_t tx_ring_ref,
grant_ref_t rx_ring_ref);
/* Check for SKBs from frontend and schedule backend processing */
void xenvif_napi_schedule_or_enable_events(struct xenvif_queue *queue);
/* Prevent the device from generating any further traffic. */
void xenvif_carrier_off(struct xenvif *vif);
int xenvif_tx_action(struct xenvif_queue *queue, int budget);
int xenvif_kthread_guest_rx(void *data);
void xenvif_kick_thread(struct xenvif_queue *queue);
int xenvif_dealloc_kthread(void *data);
irqreturn_t xenvif_ctrl_irq_fn(int irq, void *data);
bool xenvif_have_rx_work(struct xenvif_queue *queue, bool test_kthread);
bool xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb);
void xenvif_carrier_on(struct xenvif *vif);
/* Callbacks from stack when TX packet can be released */
extern const struct ubuf_info_ops xenvif_ubuf_ops;
static inline pending_ring_idx_t nr_pending_reqs(struct xenvif_queue *queue)
{
return MAX_PENDING_REQS -
queue->pending_prod + queue->pending_cons;
}
irqreturn_t xenvif_interrupt(int irq, void *dev_id);
extern bool separate_tx_rx_irq;
extern bool provides_xdp_headroom;
extern unsigned int rx_drain_timeout_msecs;
extern unsigned int rx_stall_timeout_msecs;
extern unsigned int xenvif_max_queues;
extern unsigned int xenvif_hash_cache_size;
#ifdef CONFIG_DEBUG_FS
extern struct dentry *xen_netback_dbg_root;
#endif
void xenvif_skb_zerocopy_prepare(struct xenvif_queue *queue,
struct sk_buff *skb);
void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue);
/* Multicast control */
bool xenvif_mcast_match(struct xenvif *vif, const u8 *addr);
void xenvif_mcast_addr_list_free(struct xenvif *vif);
/* Hash */
void xenvif_init_hash(struct xenvif *vif);
void xenvif_deinit_hash(struct xenvif *vif);
u32 xenvif_set_hash_alg(struct xenvif *vif, u32 alg);
u32 xenvif_get_hash_flags(struct xenvif *vif, u32 *flags);
u32 xenvif_set_hash_flags(struct xenvif *vif, u32 flags);
u32 xenvif_set_hash_key(struct xenvif *vif, u32 gref, u32 len);
u32 xenvif_set_hash_mapping_size(struct xenvif *vif, u32 size);
u32 xenvif_set_hash_mapping(struct xenvif *vif, u32 gref, u32 len,
u32 off);
void xenvif_set_skb_hash(struct xenvif *vif, struct sk_buff *skb);
#ifdef CONFIG_DEBUG_FS
void xenvif_dump_hash_info(struct xenvif *vif, struct seq_file *m);
#endif
#endif /* __XEN_NETBACK__COMMON_H__ */
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