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Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +00001#ifndef _VHOST_H
2#define _VHOST_H
3
4#include <linux/eventfd.h>
5#include <linux/vhost.h>
6#include <linux/mm.h>
7#include <linux/mutex.h>
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +00008#include <linux/poll.h>
9#include <linux/file.h>
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000010#include <linux/uio.h>
11#include <linux/virtio_config.h>
12#include <linux/virtio_ring.h>
Arun Sharma600634972011-07-26 16:09:06 -070013#include <linux/atomic.h>
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000014
Tejun Heoc23f34452010-06-02 20:40:00 +020015struct vhost_work;
16typedef void (*vhost_work_fn_t)(struct vhost_work *work);
17
Jason Wang04b96e52016-04-25 22:14:33 -040018#define VHOST_WORK_QUEUED 1
Tejun Heoc23f34452010-06-02 20:40:00 +020019struct vhost_work {
Jason Wang04b96e52016-04-25 22:14:33 -040020 struct llist_node node;
Tejun Heoc23f34452010-06-02 20:40:00 +020021 vhost_work_fn_t fn;
22 wait_queue_head_t done;
23 int flushing;
24 unsigned queue_seq;
25 unsigned done_seq;
Jason Wang04b96e52016-04-25 22:14:33 -040026 unsigned long flags;
Tejun Heoc23f34452010-06-02 20:40:00 +020027};
28
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000029/* Poll a file (eventfd or socket) */
30/* Note: there's nothing vhost specific about this structure. */
31struct vhost_poll {
32 poll_table table;
33 wait_queue_head_t *wqh;
34 wait_queue_t wait;
Tejun Heoc23f34452010-06-02 20:40:00 +020035 struct vhost_work work;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000036 unsigned long mask;
Tejun Heoc23f34452010-06-02 20:40:00 +020037 struct vhost_dev *dev;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000038};
39
Stefan Hajnoczi163049a2012-07-21 06:55:37 +000040void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn);
41void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work);
Jason Wang526d3e72016-03-04 06:24:51 -050042bool vhost_has_work(struct vhost_dev *dev);
Stefan Hajnoczi163049a2012-07-21 06:55:37 +000043
Tejun Heoc23f34452010-06-02 20:40:00 +020044void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,
45 unsigned long mask, struct vhost_dev *dev);
Jason Wang2b8b3282013-01-28 01:05:18 +000046int vhost_poll_start(struct vhost_poll *poll, struct file *file);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000047void vhost_poll_stop(struct vhost_poll *poll);
48void vhost_poll_flush(struct vhost_poll *poll);
49void vhost_poll_queue(struct vhost_poll *poll);
Asias He6ac1afb2013-05-06 16:38:21 +080050void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work);
51long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000052
53struct vhost_log {
54 u64 addr;
55 u64 len;
56};
57
Jason Wanga9709d62016-06-23 02:04:31 -040058#define START(node) ((node)->start)
59#define LAST(node) ((node)->last)
60
61struct vhost_umem_node {
62 struct rb_node rb;
63 struct list_head link;
64 __u64 start;
65 __u64 last;
66 __u64 size;
67 __u64 userspace_addr;
Jason Wang6b1e6cc2016-06-23 02:04:32 -040068 __u32 perm;
69 __u32 flags_padding;
Jason Wanga9709d62016-06-23 02:04:31 -040070 __u64 __subtree_last;
71};
72
73struct vhost_umem {
74 struct rb_root umem_tree;
75 struct list_head umem_list;
Jason Wang6b1e6cc2016-06-23 02:04:32 -040076 int numem;
Jason Wanga9709d62016-06-23 02:04:31 -040077};
78
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000079/* The virtqueue structure describes a queue attached to a device. */
80struct vhost_virtqueue {
81 struct vhost_dev *dev;
82
83 /* The actual ring of buffers. */
84 struct mutex mutex;
85 unsigned int num;
86 struct vring_desc __user *desc;
87 struct vring_avail __user *avail;
88 struct vring_used __user *used;
89 struct file *kick;
90 struct file *call;
91 struct file *error;
92 struct eventfd_ctx *call_ctx;
93 struct eventfd_ctx *error_ctx;
94 struct eventfd_ctx *log_ctx;
95
96 struct vhost_poll poll;
97
98 /* The routine to call when the Guest pings us, or timeout. */
Tejun Heoc23f34452010-06-02 20:40:00 +020099 vhost_work_fn_t handle_kick;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000100
101 /* Last available index we saw. */
102 u16 last_avail_idx;
103
104 /* Caches available index value from user. */
105 u16 avail_idx;
106
107 /* Last index we used. */
108 u16 last_used_idx;
109
110 /* Used flags */
111 u16 used_flags;
112
Michael S. Tsirkin8ea8cf82011-05-20 02:10:54 +0300113 /* Last used index value we have signalled on */
114 u16 signalled_used;
115
116 /* Last used index value we have signalled on */
117 bool signalled_used_valid;
118
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000119 /* Log writes to used structure. */
120 bool log_used;
121 u64 log_addr;
122
Jason Wange0e9b402010-09-14 23:53:05 +0800123 struct iovec iov[UIO_MAXIOV];
Jason Wang6b1e6cc2016-06-23 02:04:32 -0400124 struct iovec iotlb_iov[64];
Jason Wange0e9b402010-09-14 23:53:05 +0800125 struct iovec *indirect;
Jason Wange0e9b402010-09-14 23:53:05 +0800126 struct vring_used_elem *heads;
Asias He22fa90c2013-05-07 14:54:36 +0800127 /* Protected by virtqueue mutex. */
Jason Wanga9709d62016-06-23 02:04:31 -0400128 struct vhost_umem *umem;
Jason Wang6b1e6cc2016-06-23 02:04:32 -0400129 struct vhost_umem *iotlb;
Asias He22fa90c2013-05-07 14:54:36 +0800130 void *private_data;
Michael S. Tsirkinbd827522014-10-24 14:08:18 +0300131 u64 acked_features;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000132 /* Log write descriptors */
133 void __user *log_base;
Jason Wange0e9b402010-09-14 23:53:05 +0800134 struct vhost_log *log;
Greg Kurz2751c982015-04-24 14:27:24 +0200135
136 /* Ring endianness. Defaults to legacy native endianness.
137 * Set to true when starting a modern virtio device. */
138 bool is_le;
139#ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
140 /* Ring endianness requested by userspace for cross-endian support. */
141 bool user_be;
142#endif
Jason Wang03088132016-03-04 06:24:53 -0500143 u32 busyloop_timeout;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000144};
145
Jason Wang6b1e6cc2016-06-23 02:04:32 -0400146struct vhost_msg_node {
147 struct vhost_msg msg;
148 struct vhost_virtqueue *vq;
149 struct list_head node;
150};
151
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000152struct vhost_dev {
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000153 struct mm_struct *mm;
154 struct mutex mutex;
Asias He3ab2e422013-04-27 11:16:48 +0800155 struct vhost_virtqueue **vqs;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000156 int nvqs;
157 struct file *log_file;
158 struct eventfd_ctx *log_ctx;
Jason Wang04b96e52016-04-25 22:14:33 -0400159 struct llist_head work_list;
Tejun Heoc23f34452010-06-02 20:40:00 +0200160 struct task_struct *worker;
Jason Wanga9709d62016-06-23 02:04:31 -0400161 struct vhost_umem *umem;
Jason Wang6b1e6cc2016-06-23 02:04:32 -0400162 struct vhost_umem *iotlb;
163 spinlock_t iotlb_lock;
164 struct list_head read_list;
165 struct list_head pending_list;
166 wait_queue_head_t wait;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000167};
168
Zhi Yong Wu59566b6e2013-12-07 04:13:03 +0800169void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, int nvqs);
Asias He54db63c2013-05-06 11:15:59 +0800170long vhost_dev_set_owner(struct vhost_dev *dev);
Michael S. Tsirkin05c05352013-06-06 15:20:39 +0300171bool vhost_dev_has_owner(struct vhost_dev *dev);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000172long vhost_dev_check_owner(struct vhost_dev *);
Jason Wanga9709d62016-06-23 02:04:31 -0400173struct vhost_umem *vhost_dev_reset_owner_prepare(void);
174void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_umem *);
Michael S. Tsirkinea5d4042011-11-27 19:05:58 +0200175void vhost_dev_cleanup(struct vhost_dev *, bool locked);
Michael S. Tsirkinb2116162012-11-01 09:16:46 +0000176void vhost_dev_stop(struct vhost_dev *);
Michael S. Tsirkin935cdee2012-12-06 14:03:34 +0200177long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, void __user *argp);
178long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000179int vhost_vq_access_ok(struct vhost_virtqueue *vq);
180int vhost_log_access_ok(struct vhost_dev *);
181
Michael S. Tsirkin47283be2014-06-05 15:20:27 +0300182int vhost_get_vq_desc(struct vhost_virtqueue *,
Michael S. Tsirkind5675bd2010-06-24 16:59:59 +0300183 struct iovec iov[], unsigned int iov_count,
184 unsigned int *out_num, unsigned int *in_num,
185 struct vhost_log *log, unsigned int *log_num);
David Stevens8dd014a2010-07-27 18:52:21 +0300186void vhost_discard_vq_desc(struct vhost_virtqueue *, int n);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000187
Greg Kurz80f7d032016-02-16 15:59:44 +0100188int vhost_vq_init_access(struct vhost_virtqueue *);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000189int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len);
David Stevens8dd014a2010-07-27 18:52:21 +0300190int vhost_add_used_n(struct vhost_virtqueue *, struct vring_used_elem *heads,
191 unsigned count);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000192void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *,
David Stevens8dd014a2010-07-27 18:52:21 +0300193 unsigned int id, int len);
194void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *,
195 struct vring_used_elem *heads, unsigned count);
196void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *);
Michael S. Tsirkin8ea8cf82011-05-20 02:10:54 +0300197void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *);
Jason Wangd4a60602016-03-04 06:24:52 -0500198bool vhost_vq_avail_empty(struct vhost_dev *, struct vhost_virtqueue *);
Michael S. Tsirkin8ea8cf82011-05-20 02:10:54 +0300199bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000200
201int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
202 unsigned int log_num, u64 len);
Jason Wang6b1e6cc2016-06-23 02:04:32 -0400203int vq_iotlb_prefetch(struct vhost_virtqueue *vq);
204
205struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type);
206void vhost_enqueue_msg(struct vhost_dev *dev,
207 struct list_head *head,
208 struct vhost_msg_node *node);
209struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev,
210 struct list_head *head);
211unsigned int vhost_chr_poll(struct file *file, struct vhost_dev *dev,
212 poll_table *wait);
213ssize_t vhost_chr_read_iter(struct vhost_dev *dev, struct iov_iter *to,
214 int noblock);
215ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
216 struct iov_iter *from);
217int vhost_init_device_iotlb(struct vhost_dev *d, bool enabled);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000218
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000219#define vq_err(vq, fmt, ...) do { \
220 pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
221 if ((vq)->error_ctx) \
222 eventfd_signal((vq)->error_ctx, 1);\
223 } while (0)
224
225enum {
Michael S. Tsirkin8ea8cf82011-05-20 02:10:54 +0300226 VHOST_FEATURES = (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |
227 (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
228 (1ULL << VIRTIO_RING_F_EVENT_IDX) |
Michael S. Tsirkin4e9fa502015-09-09 22:24:56 +0300229 (1ULL << VHOST_F_LOG_ALL) |
230 (1ULL << VIRTIO_F_ANY_LAYOUT) |
231 (1ULL << VIRTIO_F_VERSION_1)
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000232};
233
Michael S. Tsirkinbd827522014-10-24 14:08:18 +0300234static inline bool vhost_has_feature(struct vhost_virtqueue *vq, int bit)
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000235{
Michael S. Tsirkinbd827522014-10-24 14:08:18 +0300236 return vq->acked_features & (1ULL << bit);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000237}
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300238
Michael S. Tsirkine407f392015-10-27 11:37:39 +0200239#ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
Greg Kurzab27c072015-04-24 14:25:12 +0200240static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq)
241{
Greg Kurz2751c982015-04-24 14:27:24 +0200242 return vq->is_le;
Greg Kurzab27c072015-04-24 14:25:12 +0200243}
Michael S. Tsirkine407f392015-10-27 11:37:39 +0200244#else
245static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq)
246{
247 return virtio_legacy_is_little_endian() || vq->is_le;
248}
249#endif
Greg Kurzab27c072015-04-24 14:25:12 +0200250
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300251/* Memory accessors */
252static inline u16 vhost16_to_cpu(struct vhost_virtqueue *vq, __virtio16 val)
253{
Greg Kurzab27c072015-04-24 14:25:12 +0200254 return __virtio16_to_cpu(vhost_is_little_endian(vq), val);
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300255}
256
257static inline __virtio16 cpu_to_vhost16(struct vhost_virtqueue *vq, u16 val)
258{
Greg Kurzab27c072015-04-24 14:25:12 +0200259 return __cpu_to_virtio16(vhost_is_little_endian(vq), val);
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300260}
261
262static inline u32 vhost32_to_cpu(struct vhost_virtqueue *vq, __virtio32 val)
263{
Greg Kurzab27c072015-04-24 14:25:12 +0200264 return __virtio32_to_cpu(vhost_is_little_endian(vq), val);
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300265}
266
267static inline __virtio32 cpu_to_vhost32(struct vhost_virtqueue *vq, u32 val)
268{
Greg Kurzab27c072015-04-24 14:25:12 +0200269 return __cpu_to_virtio32(vhost_is_little_endian(vq), val);
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300270}
271
272static inline u64 vhost64_to_cpu(struct vhost_virtqueue *vq, __virtio64 val)
273{
Greg Kurzab27c072015-04-24 14:25:12 +0200274 return __virtio64_to_cpu(vhost_is_little_endian(vq), val);
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300275}
276
277static inline __virtio64 cpu_to_vhost64(struct vhost_virtqueue *vq, u64 val)
278{
Greg Kurzab27c072015-04-24 14:25:12 +0200279 return __cpu_to_virtio64(vhost_is_little_endian(vq), val);
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300280}
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000281#endif