ibmvnic: Updated reset handling
[linux-2.6-block.git] / drivers / vhost / vhost.h
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3a4d5c94
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1#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>
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8#include <linux/poll.h>
9#include <linux/file.h>
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10#include <linux/uio.h>
11#include <linux/virtio_config.h>
12#include <linux/virtio_ring.h>
60063497 13#include <linux/atomic.h>
3a4d5c94 14
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TH
15struct vhost_work;
16typedef void (*vhost_work_fn_t)(struct vhost_work *work);
17
04b96e55 18#define VHOST_WORK_QUEUED 1
c23f3445 19struct vhost_work {
04b96e55 20 struct llist_node node;
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21 vhost_work_fn_t fn;
22 wait_queue_head_t done;
23 int flushing;
24 unsigned queue_seq;
25 unsigned done_seq;
04b96e55 26 unsigned long flags;
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27};
28
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29/* 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;
c23f3445 35 struct vhost_work work;
3a4d5c94 36 unsigned long mask;
c23f3445 37 struct vhost_dev *dev;
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38};
39
163049ae
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40void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn);
41void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work);
526d3e7f 42bool vhost_has_work(struct vhost_dev *dev);
163049ae 43
c23f3445
TH
44void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,
45 unsigned long mask, struct vhost_dev *dev);
2b8b328b 46int vhost_poll_start(struct vhost_poll *poll, struct file *file);
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47void vhost_poll_stop(struct vhost_poll *poll);
48void vhost_poll_flush(struct vhost_poll *poll);
49void vhost_poll_queue(struct vhost_poll *poll);
6ac1afbf
AH
50void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work);
51long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp);
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52
53struct vhost_log {
54 u64 addr;
55 u64 len;
56};
57
a9709d68
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58#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;
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68 __u32 perm;
69 __u32 flags_padding;
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70 __u64 __subtree_last;
71};
72
73struct vhost_umem {
74 struct rb_root umem_tree;
75 struct list_head umem_list;
6b1e6cc7 76 int numem;
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77};
78
f8894913
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79enum vhost_uaddr_type {
80 VHOST_ADDR_DESC = 0,
81 VHOST_ADDR_AVAIL = 1,
82 VHOST_ADDR_USED = 2,
83 VHOST_NUM_ADDRS = 3,
84};
85
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86/* The virtqueue structure describes a queue attached to a device. */
87struct vhost_virtqueue {
88 struct vhost_dev *dev;
89
90 /* The actual ring of buffers. */
91 struct mutex mutex;
92 unsigned int num;
93 struct vring_desc __user *desc;
94 struct vring_avail __user *avail;
95 struct vring_used __user *used;
f8894913 96 const struct vhost_umem_node *meta_iotlb[VHOST_NUM_ADDRS];
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97 struct file *kick;
98 struct file *call;
99 struct file *error;
100 struct eventfd_ctx *call_ctx;
101 struct eventfd_ctx *error_ctx;
102 struct eventfd_ctx *log_ctx;
103
104 struct vhost_poll poll;
105
106 /* The routine to call when the Guest pings us, or timeout. */
c23f3445 107 vhost_work_fn_t handle_kick;
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108
109 /* Last available index we saw. */
110 u16 last_avail_idx;
111
112 /* Caches available index value from user. */
113 u16 avail_idx;
114
115 /* Last index we used. */
116 u16 last_used_idx;
117
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118 /* Last used evet we've seen */
119 u16 last_used_event;
120
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121 /* Used flags */
122 u16 used_flags;
123
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124 /* Last used index value we have signalled on */
125 u16 signalled_used;
126
127 /* Last used index value we have signalled on */
128 bool signalled_used_valid;
129
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130 /* Log writes to used structure. */
131 bool log_used;
132 u64 log_addr;
133
e0e9b406 134 struct iovec iov[UIO_MAXIOV];
6b1e6cc7 135 struct iovec iotlb_iov[64];
e0e9b406 136 struct iovec *indirect;
e0e9b406 137 struct vring_used_elem *heads;
22fa90c7 138 /* Protected by virtqueue mutex. */
a9709d68 139 struct vhost_umem *umem;
6b1e6cc7 140 struct vhost_umem *iotlb;
22fa90c7 141 void *private_data;
bd82752a 142 u64 acked_features;
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143 /* Log write descriptors */
144 void __user *log_base;
e0e9b406 145 struct vhost_log *log;
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GK
146
147 /* Ring endianness. Defaults to legacy native endianness.
148 * Set to true when starting a modern virtio device. */
149 bool is_le;
150#ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
151 /* Ring endianness requested by userspace for cross-endian support. */
152 bool user_be;
153#endif
03088137 154 u32 busyloop_timeout;
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155};
156
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157struct vhost_msg_node {
158 struct vhost_msg msg;
159 struct vhost_virtqueue *vq;
160 struct list_head node;
161};
162
3a4d5c94 163struct vhost_dev {
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164 struct mm_struct *mm;
165 struct mutex mutex;
3ab2e420 166 struct vhost_virtqueue **vqs;
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167 int nvqs;
168 struct file *log_file;
169 struct eventfd_ctx *log_ctx;
04b96e55 170 struct llist_head work_list;
c23f3445 171 struct task_struct *worker;
a9709d68 172 struct vhost_umem *umem;
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173 struct vhost_umem *iotlb;
174 spinlock_t iotlb_lock;
175 struct list_head read_list;
176 struct list_head pending_list;
177 wait_queue_head_t wait;
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178};
179
59566b6e 180void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, int nvqs);
54db63c2 181long vhost_dev_set_owner(struct vhost_dev *dev);
05c05351 182bool vhost_dev_has_owner(struct vhost_dev *dev);
3a4d5c94 183long vhost_dev_check_owner(struct vhost_dev *);
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184struct vhost_umem *vhost_dev_reset_owner_prepare(void);
185void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_umem *);
ea5d4046 186void vhost_dev_cleanup(struct vhost_dev *, bool locked);
b211616d 187void vhost_dev_stop(struct vhost_dev *);
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188long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, void __user *argp);
189long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp);
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190int vhost_vq_access_ok(struct vhost_virtqueue *vq);
191int vhost_log_access_ok(struct vhost_dev *);
192
47283bef 193int vhost_get_vq_desc(struct vhost_virtqueue *,
d5675bd2
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194 struct iovec iov[], unsigned int iov_count,
195 unsigned int *out_num, unsigned int *in_num,
196 struct vhost_log *log, unsigned int *log_num);
8dd014ad 197void vhost_discard_vq_desc(struct vhost_virtqueue *, int n);
3a4d5c94 198
80f7d030 199int vhost_vq_init_access(struct vhost_virtqueue *);
3a4d5c94 200int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len);
8dd014ad
DS
201int vhost_add_used_n(struct vhost_virtqueue *, struct vring_used_elem *heads,
202 unsigned count);
3a4d5c94 203void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *,
8dd014ad
DS
204 unsigned int id, int len);
205void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *,
206 struct vring_used_elem *heads, unsigned count);
207void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *);
8ea8cf89 208void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *);
d4a60603 209bool vhost_vq_avail_empty(struct vhost_dev *, struct vhost_virtqueue *);
8ea8cf89 210bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *);
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211
212int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
213 unsigned int log_num, u64 len);
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214int vq_iotlb_prefetch(struct vhost_virtqueue *vq);
215
216struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type);
217void vhost_enqueue_msg(struct vhost_dev *dev,
218 struct list_head *head,
219 struct vhost_msg_node *node);
220struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev,
221 struct list_head *head);
222unsigned int vhost_chr_poll(struct file *file, struct vhost_dev *dev,
223 poll_table *wait);
224ssize_t vhost_chr_read_iter(struct vhost_dev *dev, struct iov_iter *to,
225 int noblock);
226ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
227 struct iov_iter *from);
228int vhost_init_device_iotlb(struct vhost_dev *d, bool enabled);
3a4d5c94 229
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230#define vq_err(vq, fmt, ...) do { \
231 pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
232 if ((vq)->error_ctx) \
233 eventfd_signal((vq)->error_ctx, 1);\
234 } while (0)
235
236enum {
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237 VHOST_FEATURES = (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |
238 (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
239 (1ULL << VIRTIO_RING_F_EVENT_IDX) |
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240 (1ULL << VHOST_F_LOG_ALL) |
241 (1ULL << VIRTIO_F_ANY_LAYOUT) |
242 (1ULL << VIRTIO_F_VERSION_1)
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243};
244
bd82752a 245static inline bool vhost_has_feature(struct vhost_virtqueue *vq, int bit)
3a4d5c94 246{
bd82752a 247 return vq->acked_features & (1ULL << bit);
3a4d5c94 248}
e05fd12b 249
e407f39a 250#ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
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251static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq)
252{
2751c988 253 return vq->is_le;
ab27c07f 254}
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255#else
256static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq)
257{
258 return virtio_legacy_is_little_endian() || vq->is_le;
259}
260#endif
ab27c07f 261
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262/* Memory accessors */
263static inline u16 vhost16_to_cpu(struct vhost_virtqueue *vq, __virtio16 val)
264{
ab27c07f 265 return __virtio16_to_cpu(vhost_is_little_endian(vq), val);
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266}
267
268static inline __virtio16 cpu_to_vhost16(struct vhost_virtqueue *vq, u16 val)
269{
ab27c07f 270 return __cpu_to_virtio16(vhost_is_little_endian(vq), val);
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271}
272
273static inline u32 vhost32_to_cpu(struct vhost_virtqueue *vq, __virtio32 val)
274{
ab27c07f 275 return __virtio32_to_cpu(vhost_is_little_endian(vq), val);
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276}
277
278static inline __virtio32 cpu_to_vhost32(struct vhost_virtqueue *vq, u32 val)
279{
ab27c07f 280 return __cpu_to_virtio32(vhost_is_little_endian(vq), val);
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281}
282
283static inline u64 vhost64_to_cpu(struct vhost_virtqueue *vq, __virtio64 val)
284{
ab27c07f 285 return __virtio64_to_cpu(vhost_is_little_endian(vq), val);
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286}
287
288static inline __virtio64 cpu_to_vhost64(struct vhost_virtqueue *vq, u64 val)
289{
ab27c07f 290 return __cpu_to_virtio64(vhost_is_little_endian(vq), val);
e05fd12b 291}
3a4d5c94 292#endif