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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
18struct vhost_work {
19 struct list_head node;
20 vhost_work_fn_t fn;
21 wait_queue_head_t done;
22 int flushing;
23 unsigned queue_seq;
24 unsigned done_seq;
25};
26
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000027/* Poll a file (eventfd or socket) */
28/* Note: there's nothing vhost specific about this structure. */
29struct vhost_poll {
30 poll_table table;
31 wait_queue_head_t *wqh;
32 wait_queue_t wait;
Tejun Heoc23f34452010-06-02 20:40:00 +020033 struct vhost_work work;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000034 unsigned long mask;
Tejun Heoc23f34452010-06-02 20:40:00 +020035 struct vhost_dev *dev;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000036};
37
Stefan Hajnoczi163049a2012-07-21 06:55:37 +000038void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn);
39void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work);
40
Tejun Heoc23f34452010-06-02 20:40:00 +020041void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,
42 unsigned long mask, struct vhost_dev *dev);
Jason Wang2b8b3282013-01-28 01:05:18 +000043int vhost_poll_start(struct vhost_poll *poll, struct file *file);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000044void vhost_poll_stop(struct vhost_poll *poll);
45void vhost_poll_flush(struct vhost_poll *poll);
46void vhost_poll_queue(struct vhost_poll *poll);
Asias He6ac1afb2013-05-06 16:38:21 +080047void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work);
48long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000049
50struct vhost_log {
51 u64 addr;
52 u64 len;
53};
54
55/* The virtqueue structure describes a queue attached to a device. */
56struct vhost_virtqueue {
57 struct vhost_dev *dev;
58
59 /* The actual ring of buffers. */
60 struct mutex mutex;
61 unsigned int num;
62 struct vring_desc __user *desc;
63 struct vring_avail __user *avail;
64 struct vring_used __user *used;
65 struct file *kick;
66 struct file *call;
67 struct file *error;
68 struct eventfd_ctx *call_ctx;
69 struct eventfd_ctx *error_ctx;
70 struct eventfd_ctx *log_ctx;
71
72 struct vhost_poll poll;
73
74 /* The routine to call when the Guest pings us, or timeout. */
Tejun Heoc23f34452010-06-02 20:40:00 +020075 vhost_work_fn_t handle_kick;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000076
77 /* Last available index we saw. */
78 u16 last_avail_idx;
79
80 /* Caches available index value from user. */
81 u16 avail_idx;
82
83 /* Last index we used. */
84 u16 last_used_idx;
85
86 /* Used flags */
87 u16 used_flags;
88
Michael S. Tsirkin8ea8cf82011-05-20 02:10:54 +030089 /* Last used index value we have signalled on */
90 u16 signalled_used;
91
92 /* Last used index value we have signalled on */
93 bool signalled_used_valid;
94
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +000095 /* Log writes to used structure. */
96 bool log_used;
97 u64 log_addr;
98
Jason Wange0e9b402010-09-14 23:53:05 +080099 struct iovec iov[UIO_MAXIOV];
Jason Wange0e9b402010-09-14 23:53:05 +0800100 struct iovec *indirect;
Jason Wange0e9b402010-09-14 23:53:05 +0800101 struct vring_used_elem *heads;
Asias He22fa90c2013-05-07 14:54:36 +0800102 /* Protected by virtqueue mutex. */
Michael S. Tsirkin47283be2014-06-05 15:20:27 +0300103 struct vhost_memory *memory;
Asias He22fa90c2013-05-07 14:54:36 +0800104 void *private_data;
Michael S. Tsirkinbd827522014-10-24 14:08:18 +0300105 u64 acked_features;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000106 /* Log write descriptors */
107 void __user *log_base;
Jason Wange0e9b402010-09-14 23:53:05 +0800108 struct vhost_log *log;
Greg Kurz2751c982015-04-24 14:27:24 +0200109
110 /* Ring endianness. Defaults to legacy native endianness.
111 * Set to true when starting a modern virtio device. */
112 bool is_le;
113#ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
114 /* Ring endianness requested by userspace for cross-endian support. */
115 bool user_be;
116#endif
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000117};
118
119struct vhost_dev {
Michael S. Tsirkin47283be2014-06-05 15:20:27 +0300120 struct vhost_memory *memory;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000121 struct mm_struct *mm;
122 struct mutex mutex;
Asias He3ab2e422013-04-27 11:16:48 +0800123 struct vhost_virtqueue **vqs;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000124 int nvqs;
125 struct file *log_file;
126 struct eventfd_ctx *log_ctx;
Tejun Heoc23f34452010-06-02 20:40:00 +0200127 spinlock_t work_lock;
128 struct list_head work_list;
129 struct task_struct *worker;
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000130};
131
Zhi Yong Wu59566b6e2013-12-07 04:13:03 +0800132void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, int nvqs);
Asias He54db63c2013-05-06 11:15:59 +0800133long vhost_dev_set_owner(struct vhost_dev *dev);
Michael S. Tsirkin05c05352013-06-06 15:20:39 +0300134bool vhost_dev_has_owner(struct vhost_dev *dev);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000135long vhost_dev_check_owner(struct vhost_dev *);
Michael S. Tsirkin150b9e52013-04-28 17:12:08 +0300136struct vhost_memory *vhost_dev_reset_owner_prepare(void);
137void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_memory *);
Michael S. Tsirkinea5d4042011-11-27 19:05:58 +0200138void vhost_dev_cleanup(struct vhost_dev *, bool locked);
Michael S. Tsirkinb2116162012-11-01 09:16:46 +0000139void vhost_dev_stop(struct vhost_dev *);
Michael S. Tsirkin935cdee2012-12-06 14:03:34 +0200140long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, void __user *argp);
141long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000142int vhost_vq_access_ok(struct vhost_virtqueue *vq);
143int vhost_log_access_ok(struct vhost_dev *);
144
Michael S. Tsirkin47283be2014-06-05 15:20:27 +0300145int vhost_get_vq_desc(struct vhost_virtqueue *,
Michael S. Tsirkind5675bd2010-06-24 16:59:59 +0300146 struct iovec iov[], unsigned int iov_count,
147 unsigned int *out_num, unsigned int *in_num,
148 struct vhost_log *log, unsigned int *log_num);
David Stevens8dd014a2010-07-27 18:52:21 +0300149void vhost_discard_vq_desc(struct vhost_virtqueue *, int n);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000150
Jason Wangf59281d2011-06-21 18:04:27 +0800151int vhost_init_used(struct vhost_virtqueue *);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000152int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len);
David Stevens8dd014a2010-07-27 18:52:21 +0300153int vhost_add_used_n(struct vhost_virtqueue *, struct vring_used_elem *heads,
154 unsigned count);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000155void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *,
David Stevens8dd014a2010-07-27 18:52:21 +0300156 unsigned int id, int len);
157void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *,
158 struct vring_used_elem *heads, unsigned count);
159void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *);
Michael S. Tsirkin8ea8cf82011-05-20 02:10:54 +0300160void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *);
161bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000162
163int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
164 unsigned int log_num, u64 len);
165
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000166#define vq_err(vq, fmt, ...) do { \
167 pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
168 if ((vq)->error_ctx) \
169 eventfd_signal((vq)->error_ctx, 1);\
170 } while (0)
171
172enum {
Michael S. Tsirkin8ea8cf82011-05-20 02:10:54 +0300173 VHOST_FEATURES = (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |
174 (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
175 (1ULL << VIRTIO_RING_F_EVENT_IDX) |
Michael S. Tsirkin4e9fa502015-09-09 22:24:56 +0300176 (1ULL << VHOST_F_LOG_ALL) |
177 (1ULL << VIRTIO_F_ANY_LAYOUT) |
178 (1ULL << VIRTIO_F_VERSION_1)
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000179};
180
Michael S. Tsirkinbd827522014-10-24 14:08:18 +0300181static inline bool vhost_has_feature(struct vhost_virtqueue *vq, int bit)
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000182{
Michael S. Tsirkinbd827522014-10-24 14:08:18 +0300183 return vq->acked_features & (1ULL << bit);
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000184}
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300185
Michael S. Tsirkine407f392015-10-27 11:37:39 +0200186#ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
Greg Kurzab27c072015-04-24 14:25:12 +0200187static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq)
188{
Greg Kurz2751c982015-04-24 14:27:24 +0200189 return vq->is_le;
Greg Kurzab27c072015-04-24 14:25:12 +0200190}
Michael S. Tsirkine407f392015-10-27 11:37:39 +0200191#else
192static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq)
193{
194 return virtio_legacy_is_little_endian() || vq->is_le;
195}
196#endif
Greg Kurzab27c072015-04-24 14:25:12 +0200197
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300198/* Memory accessors */
199static inline u16 vhost16_to_cpu(struct vhost_virtqueue *vq, __virtio16 val)
200{
Greg Kurzab27c072015-04-24 14:25:12 +0200201 return __virtio16_to_cpu(vhost_is_little_endian(vq), val);
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300202}
203
204static inline __virtio16 cpu_to_vhost16(struct vhost_virtqueue *vq, u16 val)
205{
Greg Kurzab27c072015-04-24 14:25:12 +0200206 return __cpu_to_virtio16(vhost_is_little_endian(vq), val);
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300207}
208
209static inline u32 vhost32_to_cpu(struct vhost_virtqueue *vq, __virtio32 val)
210{
Greg Kurzab27c072015-04-24 14:25:12 +0200211 return __virtio32_to_cpu(vhost_is_little_endian(vq), val);
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300212}
213
214static inline __virtio32 cpu_to_vhost32(struct vhost_virtqueue *vq, u32 val)
215{
Greg Kurzab27c072015-04-24 14:25:12 +0200216 return __cpu_to_virtio32(vhost_is_little_endian(vq), val);
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300217}
218
219static inline u64 vhost64_to_cpu(struct vhost_virtqueue *vq, __virtio64 val)
220{
Greg Kurzab27c072015-04-24 14:25:12 +0200221 return __virtio64_to_cpu(vhost_is_little_endian(vq), val);
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300222}
223
224static inline __virtio64 cpu_to_vhost64(struct vhost_virtqueue *vq, u64 val)
225{
Greg Kurzab27c072015-04-24 14:25:12 +0200226 return __cpu_to_virtio64(vhost_is_little_endian(vq), val);
Michael S. Tsirkine05fd122014-10-24 11:48:17 +0300227}
Michael S. Tsirkin3a4d5c94e2010-01-14 06:17:27 +0000228#endif