/* * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include typedef unsigned int pending_ring_idx_t; #define INVALID_PENDING_RING_IDX (~0U) struct pending_tx_info { struct xen_netif_tx_request req; /* tx request */ /* 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 callback_struct; }; #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 XEN_NETIF_TX_RING_SIZE /* 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) #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. */ unsigned int rx_bytes; unsigned int rx_packets; unsigned int tx_bytes; unsigned int 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; }; 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 */ /* 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[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; bool stalled; struct gnttab_copy grant_copy_op[MAX_GRANT_COPY_OPS]; /* 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]; /* 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; }; /* Maximum number of Rx slots a to-guest packet may use, including the * slot needed for GSO meta-data. */ #define XEN_NETBK_RX_SLOTS_MAX (MAX_SKB_FRAGS + 1) enum state_bit_shift { /* This bit marks that the vif is connected */ VIF_STATUS_CONNECTED, }; struct xenvif { /* Unique identifier for this interface. */ domid_t domid; unsigned int handle; 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; /* 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 xenbus_watch credit_watch; spinlock_t lock; #ifdef CONFIG_DEBUG_FS struct dentry *xenvif_dbg_root; #endif /* 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(unsigned long data); 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(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(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_queue_stopped(struct xenvif_queue *queue); void xenvif_wake_queue(struct xenvif_queue *queue); /* (Un)Map communication rings. */ void xenvif_unmap_frontend_rings(struct xenvif_queue *queue); int xenvif_map_frontend_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); void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb); /* Determine whether the needed number of slots (req) are available, * and set req_event if not. */ bool xenvif_rx_ring_slots_available(struct xenvif_queue *queue, int needed); void xenvif_carrier_on(struct xenvif *vif); /* Callback from stack when TX packet can be released */ void xenvif_zerocopy_callback(struct ubuf_info *ubuf, bool zerocopy_success); /* Unmap a pending page and release it back to the guest */ void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx); static inline pending_ring_idx_t nr_pending_reqs(struct xenvif_queue *queue) { return MAX_PENDING_REQS - queue->pending_prod + queue->pending_cons; } /* Callback from stack when TX packet can be released */ void xenvif_zerocopy_callback(struct ubuf_info *ubuf, bool zerocopy_success); irqreturn_t xenvif_interrupt(int irq, void *dev_id); extern bool separate_tx_rx_irq; extern unsigned int rx_drain_timeout_msecs; extern unsigned int rx_stall_timeout_msecs; extern unsigned int xenvif_max_queues; #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); #endif /* __XEN_NETBACK__COMMON_H__ */