Commit | Line | Data |
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7a338472 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
3a4d5c94 MT |
2 | /* Copyright (C) 2009 Red Hat, Inc. |
3 | * Copyright (C) 2006 Rusty Russell IBM Corporation | |
4 | * | |
5 | * Author: Michael S. Tsirkin <mst@redhat.com> | |
6 | * | |
7 | * Inspiration, some code, and most witty comments come from | |
61516587 | 8 | * Documentation/virtual/lguest/lguest.c, by Rusty Russell |
3a4d5c94 | 9 | * |
3a4d5c94 MT |
10 | * Generic code for virtio server in host kernel. |
11 | */ | |
12 | ||
13 | #include <linux/eventfd.h> | |
14 | #include <linux/vhost.h> | |
35596b27 | 15 | #include <linux/uio.h> |
3a4d5c94 MT |
16 | #include <linux/mm.h> |
17 | #include <linux/miscdevice.h> | |
18 | #include <linux/mutex.h> | |
3a4d5c94 MT |
19 | #include <linux/poll.h> |
20 | #include <linux/file.h> | |
21 | #include <linux/highmem.h> | |
5a0e3ad6 | 22 | #include <linux/slab.h> |
4de7255f | 23 | #include <linux/vmalloc.h> |
c23f3445 | 24 | #include <linux/kthread.h> |
6ac1afbf | 25 | #include <linux/module.h> |
bcfeacab | 26 | #include <linux/sort.h> |
6e84f315 | 27 | #include <linux/sched/mm.h> |
174cd4b1 | 28 | #include <linux/sched/signal.h> |
6e890c5d | 29 | #include <linux/sched/vhost_task.h> |
a9709d68 | 30 | #include <linux/interval_tree_generic.h> |
ff002269 | 31 | #include <linux/nospec.h> |
8f6a7f96 | 32 | #include <linux/kcov.h> |
3a4d5c94 | 33 | |
3a4d5c94 MT |
34 | #include "vhost.h" |
35 | ||
c9ce42f7 IM |
36 | static ushort max_mem_regions = 64; |
37 | module_param(max_mem_regions, ushort, 0444); | |
38 | MODULE_PARM_DESC(max_mem_regions, | |
39 | "Maximum number of memory regions in memory map. (default: 64)"); | |
6b1e6cc7 JW |
40 | static int max_iotlb_entries = 2048; |
41 | module_param(max_iotlb_entries, int, 0444); | |
42 | MODULE_PARM_DESC(max_iotlb_entries, | |
43 | "Maximum number of iotlb entries. (default: 2048)"); | |
c9ce42f7 | 44 | |
3a4d5c94 | 45 | enum { |
3a4d5c94 MT |
46 | VHOST_MEMORY_F_LOG = 0x1, |
47 | }; | |
48 | ||
3b1bbe89 MT |
49 | #define vhost_used_event(vq) ((__virtio16 __user *)&vq->avail->ring[vq->num]) |
50 | #define vhost_avail_event(vq) ((__virtio16 __user *)&vq->used->ring[vq->num]) | |
8ea8cf89 | 51 | |
2751c988 | 52 | #ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY |
c5072037 | 53 | static void vhost_disable_cross_endian(struct vhost_virtqueue *vq) |
2751c988 GK |
54 | { |
55 | vq->user_be = !virtio_legacy_is_little_endian(); | |
56 | } | |
57 | ||
c5072037 GK |
58 | static void vhost_enable_cross_endian_big(struct vhost_virtqueue *vq) |
59 | { | |
60 | vq->user_be = true; | |
61 | } | |
62 | ||
63 | static void vhost_enable_cross_endian_little(struct vhost_virtqueue *vq) | |
64 | { | |
65 | vq->user_be = false; | |
66 | } | |
67 | ||
2751c988 GK |
68 | static long vhost_set_vring_endian(struct vhost_virtqueue *vq, int __user *argp) |
69 | { | |
70 | struct vhost_vring_state s; | |
71 | ||
72 | if (vq->private_data) | |
73 | return -EBUSY; | |
74 | ||
75 | if (copy_from_user(&s, argp, sizeof(s))) | |
76 | return -EFAULT; | |
77 | ||
78 | if (s.num != VHOST_VRING_LITTLE_ENDIAN && | |
79 | s.num != VHOST_VRING_BIG_ENDIAN) | |
80 | return -EINVAL; | |
81 | ||
c5072037 GK |
82 | if (s.num == VHOST_VRING_BIG_ENDIAN) |
83 | vhost_enable_cross_endian_big(vq); | |
84 | else | |
85 | vhost_enable_cross_endian_little(vq); | |
2751c988 GK |
86 | |
87 | return 0; | |
88 | } | |
89 | ||
90 | static long vhost_get_vring_endian(struct vhost_virtqueue *vq, u32 idx, | |
91 | int __user *argp) | |
92 | { | |
93 | struct vhost_vring_state s = { | |
94 | .index = idx, | |
95 | .num = vq->user_be | |
96 | }; | |
97 | ||
98 | if (copy_to_user(argp, &s, sizeof(s))) | |
99 | return -EFAULT; | |
100 | ||
101 | return 0; | |
102 | } | |
103 | ||
104 | static void vhost_init_is_le(struct vhost_virtqueue *vq) | |
105 | { | |
106 | /* Note for legacy virtio: user_be is initialized at reset time | |
107 | * according to the host endianness. If userspace does not set an | |
108 | * explicit endianness, the default behavior is native endian, as | |
109 | * expected by legacy virtio. | |
110 | */ | |
111 | vq->is_le = vhost_has_feature(vq, VIRTIO_F_VERSION_1) || !vq->user_be; | |
112 | } | |
113 | #else | |
c5072037 | 114 | static void vhost_disable_cross_endian(struct vhost_virtqueue *vq) |
2751c988 GK |
115 | { |
116 | } | |
117 | ||
118 | static long vhost_set_vring_endian(struct vhost_virtqueue *vq, int __user *argp) | |
119 | { | |
120 | return -ENOIOCTLCMD; | |
121 | } | |
122 | ||
123 | static long vhost_get_vring_endian(struct vhost_virtqueue *vq, u32 idx, | |
124 | int __user *argp) | |
125 | { | |
126 | return -ENOIOCTLCMD; | |
127 | } | |
128 | ||
129 | static void vhost_init_is_le(struct vhost_virtqueue *vq) | |
130 | { | |
cda8bba0 HP |
131 | vq->is_le = vhost_has_feature(vq, VIRTIO_F_VERSION_1) |
132 | || virtio_legacy_is_little_endian(); | |
2751c988 GK |
133 | } |
134 | #endif /* CONFIG_VHOST_CROSS_ENDIAN_LEGACY */ | |
135 | ||
c5072037 GK |
136 | static void vhost_reset_is_le(struct vhost_virtqueue *vq) |
137 | { | |
cda8bba0 | 138 | vhost_init_is_le(vq); |
c5072037 GK |
139 | } |
140 | ||
7235acdb JW |
141 | struct vhost_flush_struct { |
142 | struct vhost_work work; | |
143 | struct completion wait_event; | |
144 | }; | |
145 | ||
146 | static void vhost_flush_work(struct vhost_work *work) | |
147 | { | |
148 | struct vhost_flush_struct *s; | |
149 | ||
150 | s = container_of(work, struct vhost_flush_struct, work); | |
151 | complete(&s->wait_event); | |
152 | } | |
153 | ||
3a4d5c94 MT |
154 | static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh, |
155 | poll_table *pt) | |
156 | { | |
157 | struct vhost_poll *poll; | |
3a4d5c94 | 158 | |
d47effe1 | 159 | poll = container_of(pt, struct vhost_poll, table); |
3a4d5c94 MT |
160 | poll->wqh = wqh; |
161 | add_wait_queue(wqh, &poll->wait); | |
162 | } | |
163 | ||
ac6424b9 | 164 | static int vhost_poll_wakeup(wait_queue_entry_t *wait, unsigned mode, int sync, |
3a4d5c94 MT |
165 | void *key) |
166 | { | |
c23f3445 | 167 | struct vhost_poll *poll = container_of(wait, struct vhost_poll, wait); |
01fcb1cb | 168 | struct vhost_work *work = &poll->work; |
c23f3445 | 169 | |
3ad6f93e | 170 | if (!(key_to_poll(key) & poll->mask)) |
3a4d5c94 MT |
171 | return 0; |
172 | ||
01fcb1cb JW |
173 | if (!poll->dev->use_worker) |
174 | work->fn(work); | |
175 | else | |
176 | vhost_poll_queue(poll); | |
177 | ||
3a4d5c94 MT |
178 | return 0; |
179 | } | |
180 | ||
163049ae | 181 | void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn) |
87d6a412 | 182 | { |
04b96e55 | 183 | clear_bit(VHOST_WORK_QUEUED, &work->flags); |
87d6a412 | 184 | work->fn = fn; |
87d6a412 | 185 | } |
6ac1afbf | 186 | EXPORT_SYMBOL_GPL(vhost_work_init); |
87d6a412 | 187 | |
3a4d5c94 | 188 | /* Init poll structure */ |
c23f3445 | 189 | void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn, |
493b94bf MC |
190 | __poll_t mask, struct vhost_dev *dev, |
191 | struct vhost_virtqueue *vq) | |
3a4d5c94 | 192 | { |
3a4d5c94 MT |
193 | init_waitqueue_func_entry(&poll->wait, vhost_poll_wakeup); |
194 | init_poll_funcptr(&poll->table, vhost_poll_func); | |
195 | poll->mask = mask; | |
c23f3445 | 196 | poll->dev = dev; |
2b8b328b | 197 | poll->wqh = NULL; |
493b94bf | 198 | poll->vq = vq; |
c23f3445 | 199 | |
87d6a412 | 200 | vhost_work_init(&poll->work, fn); |
3a4d5c94 | 201 | } |
6ac1afbf | 202 | EXPORT_SYMBOL_GPL(vhost_poll_init); |
3a4d5c94 MT |
203 | |
204 | /* Start polling a file. We add ourselves to file's wait queue. The caller must | |
205 | * keep a reference to a file until after vhost_poll_stop is called. */ | |
2b8b328b | 206 | int vhost_poll_start(struct vhost_poll *poll, struct file *file) |
3a4d5c94 | 207 | { |
e6c8adca | 208 | __poll_t mask; |
d47effe1 | 209 | |
70181d51 JW |
210 | if (poll->wqh) |
211 | return 0; | |
212 | ||
9965ed17 | 213 | mask = vfs_poll(file, &poll->table); |
3a4d5c94 | 214 | if (mask) |
3ad6f93e | 215 | vhost_poll_wakeup(&poll->wait, 0, 0, poll_to_key(mask)); |
a9a08845 | 216 | if (mask & EPOLLERR) { |
dc6455a7 | 217 | vhost_poll_stop(poll); |
896fc242 | 218 | return -EINVAL; |
2b8b328b JW |
219 | } |
220 | ||
896fc242 | 221 | return 0; |
3a4d5c94 | 222 | } |
6ac1afbf | 223 | EXPORT_SYMBOL_GPL(vhost_poll_start); |
3a4d5c94 MT |
224 | |
225 | /* Stop polling a file. After this function returns, it becomes safe to drop the | |
226 | * file reference. You must also flush afterwards. */ | |
227 | void vhost_poll_stop(struct vhost_poll *poll) | |
228 | { | |
2b8b328b JW |
229 | if (poll->wqh) { |
230 | remove_wait_queue(poll->wqh, &poll->wait); | |
231 | poll->wqh = NULL; | |
232 | } | |
3a4d5c94 | 233 | } |
6ac1afbf | 234 | EXPORT_SYMBOL_GPL(vhost_poll_stop); |
3a4d5c94 | 235 | |
0921dddc MC |
236 | static bool vhost_worker_queue(struct vhost_worker *worker, |
237 | struct vhost_work *work) | |
3a4d5c94 | 238 | { |
0921dddc | 239 | if (!worker) |
c011bb66 MC |
240 | return false; |
241 | /* | |
242 | * vsock can queue while we do a VHOST_SET_OWNER, so we have a smp_wmb | |
243 | * when setting up the worker. We don't have a smp_rmb here because | |
244 | * test_and_set_bit gives us a mb already. | |
245 | */ | |
04b96e55 JW |
246 | if (!test_and_set_bit(VHOST_WORK_QUEUED, &work->flags)) { |
247 | /* We can only add the work to the list after we're | |
248 | * sure it was not in the list. | |
635abf01 | 249 | * test_and_set_bit() implies a memory barrier. |
04b96e55 | 250 | */ |
0921dddc MC |
251 | llist_add(&work->node, &worker->work_list); |
252 | vhost_task_wake(worker->vtsk); | |
c23f3445 | 253 | } |
c011bb66 MC |
254 | |
255 | return true; | |
3a4d5c94 | 256 | } |
0921dddc | 257 | |
0921dddc MC |
258 | bool vhost_vq_work_queue(struct vhost_virtqueue *vq, struct vhost_work *work) |
259 | { | |
260 | return vhost_worker_queue(vq->worker, work); | |
261 | } | |
262 | EXPORT_SYMBOL_GPL(vhost_vq_work_queue); | |
263 | ||
a6fc0473 | 264 | static void vhost_worker_flush(struct vhost_worker *worker) |
0921dddc MC |
265 | { |
266 | struct vhost_flush_struct flush; | |
267 | ||
268 | init_completion(&flush.wait_event); | |
269 | vhost_work_init(&flush.work, vhost_flush_work); | |
270 | ||
a6fc0473 | 271 | if (vhost_worker_queue(worker, &flush.work)) |
0921dddc MC |
272 | wait_for_completion(&flush.wait_event); |
273 | } | |
a6fc0473 MC |
274 | |
275 | void vhost_vq_flush(struct vhost_virtqueue *vq) | |
276 | { | |
277 | vhost_worker_flush(vq->worker); | |
278 | } | |
279 | EXPORT_SYMBOL_GPL(vhost_vq_flush); | |
280 | ||
281 | void vhost_dev_flush(struct vhost_dev *dev) | |
282 | { | |
283 | vhost_worker_flush(dev->worker); | |
284 | } | |
0921dddc MC |
285 | EXPORT_SYMBOL_GPL(vhost_dev_flush); |
286 | ||
526d3e7f | 287 | /* A lockless hint for busy polling code to exit the loop */ |
9784df15 | 288 | bool vhost_vq_has_work(struct vhost_virtqueue *vq) |
526d3e7f | 289 | { |
9784df15 | 290 | return !llist_empty(&vq->worker->work_list); |
526d3e7f | 291 | } |
9784df15 | 292 | EXPORT_SYMBOL_GPL(vhost_vq_has_work); |
526d3e7f | 293 | |
87d6a412 MT |
294 | void vhost_poll_queue(struct vhost_poll *poll) |
295 | { | |
493b94bf | 296 | vhost_vq_work_queue(poll->vq, &poll->work); |
87d6a412 | 297 | } |
6ac1afbf | 298 | EXPORT_SYMBOL_GPL(vhost_poll_queue); |
87d6a412 | 299 | |
f8894913 JW |
300 | static void __vhost_vq_meta_reset(struct vhost_virtqueue *vq) |
301 | { | |
302 | int j; | |
303 | ||
304 | for (j = 0; j < VHOST_NUM_ADDRS; j++) | |
305 | vq->meta_iotlb[j] = NULL; | |
306 | } | |
307 | ||
308 | static void vhost_vq_meta_reset(struct vhost_dev *d) | |
309 | { | |
310 | int i; | |
311 | ||
86a07da3 | 312 | for (i = 0; i < d->nvqs; ++i) |
f8894913 JW |
313 | __vhost_vq_meta_reset(d->vqs[i]); |
314 | } | |
315 | ||
265a0ad8 ZL |
316 | static void vhost_vring_call_reset(struct vhost_vring_call *call_ctx) |
317 | { | |
318 | call_ctx->ctx = NULL; | |
319 | memset(&call_ctx->producer, 0x0, sizeof(struct irq_bypass_producer)); | |
265a0ad8 ZL |
320 | } |
321 | ||
6bcf3422 MC |
322 | bool vhost_vq_is_setup(struct vhost_virtqueue *vq) |
323 | { | |
324 | return vq->avail && vq->desc && vq->used && vhost_vq_access_ok(vq); | |
325 | } | |
326 | EXPORT_SYMBOL_GPL(vhost_vq_is_setup); | |
327 | ||
3a4d5c94 MT |
328 | static void vhost_vq_reset(struct vhost_dev *dev, |
329 | struct vhost_virtqueue *vq) | |
330 | { | |
331 | vq->num = 1; | |
332 | vq->desc = NULL; | |
333 | vq->avail = NULL; | |
334 | vq->used = NULL; | |
335 | vq->last_avail_idx = 0; | |
336 | vq->avail_idx = 0; | |
337 | vq->last_used_idx = 0; | |
8ea8cf89 MT |
338 | vq->signalled_used = 0; |
339 | vq->signalled_used_valid = false; | |
3a4d5c94 | 340 | vq->used_flags = 0; |
3a4d5c94 MT |
341 | vq->log_used = false; |
342 | vq->log_addr = -1ull; | |
3a4d5c94 | 343 | vq->private_data = NULL; |
ea16c514 | 344 | vq->acked_features = 0; |
429711ae | 345 | vq->acked_backend_features = 0; |
3a4d5c94 MT |
346 | vq->log_base = NULL; |
347 | vq->error_ctx = NULL; | |
3a4d5c94 | 348 | vq->kick = NULL; |
73a99f08 | 349 | vq->log_ctx = NULL; |
c5072037 | 350 | vhost_disable_cross_endian(vq); |
beb691e6 | 351 | vhost_reset_is_le(vq); |
03088137 | 352 | vq->busyloop_timeout = 0; |
a9709d68 | 353 | vq->umem = NULL; |
6b1e6cc7 | 354 | vq->iotlb = NULL; |
737bdb64 | 355 | vq->worker = NULL; |
265a0ad8 | 356 | vhost_vring_call_reset(&vq->call_ctx); |
f8894913 | 357 | __vhost_vq_meta_reset(vq); |
3a4d5c94 MT |
358 | } |
359 | ||
f9010dbd | 360 | static bool vhost_worker(void *data) |
c23f3445 | 361 | { |
1a5f8090 | 362 | struct vhost_worker *worker = data; |
04b96e55 JW |
363 | struct vhost_work *work, *work_next; |
364 | struct llist_node *node; | |
c23f3445 | 365 | |
f9010dbd MC |
366 | node = llist_del_all(&worker->work_list); |
367 | if (node) { | |
4b13cbef MC |
368 | __set_current_state(TASK_RUNNING); |
369 | ||
04b96e55 JW |
370 | node = llist_reverse_order(node); |
371 | /* make sure flag is seen after deletion */ | |
372 | smp_wmb(); | |
373 | llist_for_each_entry_safe(work, work_next, node, node) { | |
374 | clear_bit(VHOST_WORK_QUEUED, &work->flags); | |
1a5f8090 | 375 | kcov_remote_start_common(worker->kcov_handle); |
c23f3445 | 376 | work->fn(work); |
8f6a7f96 | 377 | kcov_remote_stop(); |
05bfb338 | 378 | cond_resched(); |
04b96e55 | 379 | } |
c23f3445 | 380 | } |
6e890c5d | 381 | |
f9010dbd | 382 | return !!node; |
c23f3445 TH |
383 | } |
384 | ||
bab632d6 MT |
385 | static void vhost_vq_free_iovecs(struct vhost_virtqueue *vq) |
386 | { | |
387 | kfree(vq->indirect); | |
388 | vq->indirect = NULL; | |
389 | kfree(vq->log); | |
390 | vq->log = NULL; | |
391 | kfree(vq->heads); | |
392 | vq->heads = NULL; | |
bab632d6 MT |
393 | } |
394 | ||
e0e9b406 JW |
395 | /* Helper to allocate iovec buffers for all vqs. */ |
396 | static long vhost_dev_alloc_iovecs(struct vhost_dev *dev) | |
397 | { | |
6d5e6aa8 | 398 | struct vhost_virtqueue *vq; |
e0e9b406 | 399 | int i; |
d47effe1 | 400 | |
e0e9b406 | 401 | for (i = 0; i < dev->nvqs; ++i) { |
6d5e6aa8 | 402 | vq = dev->vqs[i]; |
6da2ec56 KC |
403 | vq->indirect = kmalloc_array(UIO_MAXIOV, |
404 | sizeof(*vq->indirect), | |
405 | GFP_KERNEL); | |
b46a0bf7 | 406 | vq->log = kmalloc_array(dev->iov_limit, sizeof(*vq->log), |
6da2ec56 | 407 | GFP_KERNEL); |
b46a0bf7 | 408 | vq->heads = kmalloc_array(dev->iov_limit, sizeof(*vq->heads), |
6da2ec56 | 409 | GFP_KERNEL); |
6d5e6aa8 | 410 | if (!vq->indirect || !vq->log || !vq->heads) |
e0e9b406 JW |
411 | goto err_nomem; |
412 | } | |
413 | return 0; | |
d47effe1 | 414 | |
e0e9b406 | 415 | err_nomem: |
bab632d6 | 416 | for (; i >= 0; --i) |
3ab2e420 | 417 | vhost_vq_free_iovecs(dev->vqs[i]); |
e0e9b406 JW |
418 | return -ENOMEM; |
419 | } | |
420 | ||
421 | static void vhost_dev_free_iovecs(struct vhost_dev *dev) | |
422 | { | |
423 | int i; | |
d47effe1 | 424 | |
bab632d6 | 425 | for (i = 0; i < dev->nvqs; ++i) |
3ab2e420 | 426 | vhost_vq_free_iovecs(dev->vqs[i]); |
e0e9b406 JW |
427 | } |
428 | ||
e82b9b07 JW |
429 | bool vhost_exceeds_weight(struct vhost_virtqueue *vq, |
430 | int pkts, int total_len) | |
431 | { | |
432 | struct vhost_dev *dev = vq->dev; | |
433 | ||
434 | if ((dev->byte_weight && total_len >= dev->byte_weight) || | |
435 | pkts >= dev->weight) { | |
436 | vhost_poll_queue(&vq->poll); | |
437 | return true; | |
438 | } | |
439 | ||
440 | return false; | |
441 | } | |
442 | EXPORT_SYMBOL_GPL(vhost_exceeds_weight); | |
443 | ||
4942e825 JW |
444 | static size_t vhost_get_avail_size(struct vhost_virtqueue *vq, |
445 | unsigned int num) | |
446 | { | |
447 | size_t event __maybe_unused = | |
448 | vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; | |
449 | ||
e4be66e5 | 450 | return size_add(struct_size(vq->avail, ring, num), event); |
4942e825 JW |
451 | } |
452 | ||
453 | static size_t vhost_get_used_size(struct vhost_virtqueue *vq, | |
454 | unsigned int num) | |
455 | { | |
456 | size_t event __maybe_unused = | |
457 | vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; | |
458 | ||
e4be66e5 | 459 | return size_add(struct_size(vq->used, ring, num), event); |
4942e825 JW |
460 | } |
461 | ||
462 | static size_t vhost_get_desc_size(struct vhost_virtqueue *vq, | |
463 | unsigned int num) | |
464 | { | |
465 | return sizeof(*vq->desc) * num; | |
466 | } | |
467 | ||
59566b6e | 468 | void vhost_dev_init(struct vhost_dev *dev, |
e82b9b07 | 469 | struct vhost_virtqueue **vqs, int nvqs, |
792a4f2e | 470 | int iov_limit, int weight, int byte_weight, |
01fcb1cb | 471 | bool use_worker, |
91233ad7 | 472 | int (*msg_handler)(struct vhost_dev *dev, u32 asid, |
792a4f2e | 473 | struct vhost_iotlb_msg *msg)) |
3a4d5c94 | 474 | { |
6d5e6aa8 | 475 | struct vhost_virtqueue *vq; |
3a4d5c94 | 476 | int i; |
c23f3445 | 477 | |
3a4d5c94 MT |
478 | dev->vqs = vqs; |
479 | dev->nvqs = nvqs; | |
480 | mutex_init(&dev->mutex); | |
481 | dev->log_ctx = NULL; | |
a9709d68 | 482 | dev->umem = NULL; |
6b1e6cc7 | 483 | dev->iotlb = NULL; |
3a4d5c94 | 484 | dev->mm = NULL; |
c011bb66 | 485 | dev->worker = NULL; |
b46a0bf7 | 486 | dev->iov_limit = iov_limit; |
e82b9b07 JW |
487 | dev->weight = weight; |
488 | dev->byte_weight = byte_weight; | |
01fcb1cb | 489 | dev->use_worker = use_worker; |
792a4f2e | 490 | dev->msg_handler = msg_handler; |
6b1e6cc7 JW |
491 | init_waitqueue_head(&dev->wait); |
492 | INIT_LIST_HEAD(&dev->read_list); | |
493 | INIT_LIST_HEAD(&dev->pending_list); | |
494 | spin_lock_init(&dev->iotlb_lock); | |
3d2c7d37 | 495 | |
3a4d5c94 MT |
496 | |
497 | for (i = 0; i < dev->nvqs; ++i) { | |
6d5e6aa8 AH |
498 | vq = dev->vqs[i]; |
499 | vq->log = NULL; | |
500 | vq->indirect = NULL; | |
501 | vq->heads = NULL; | |
502 | vq->dev = dev; | |
503 | mutex_init(&vq->mutex); | |
504 | vhost_vq_reset(dev, vq); | |
505 | if (vq->handle_kick) | |
506 | vhost_poll_init(&vq->poll, vq->handle_kick, | |
493b94bf | 507 | EPOLLIN, dev, vq); |
3a4d5c94 | 508 | } |
3a4d5c94 | 509 | } |
6ac1afbf | 510 | EXPORT_SYMBOL_GPL(vhost_dev_init); |
3a4d5c94 MT |
511 | |
512 | /* Caller should have device mutex */ | |
513 | long vhost_dev_check_owner(struct vhost_dev *dev) | |
514 | { | |
515 | /* Are you the owner? If not, I don't think you mean to do that */ | |
516 | return dev->mm == current->mm ? 0 : -EPERM; | |
517 | } | |
6ac1afbf | 518 | EXPORT_SYMBOL_GPL(vhost_dev_check_owner); |
3a4d5c94 | 519 | |
05c05351 MT |
520 | /* Caller should have device mutex */ |
521 | bool vhost_dev_has_owner(struct vhost_dev *dev) | |
522 | { | |
523 | return dev->mm; | |
524 | } | |
6ac1afbf | 525 | EXPORT_SYMBOL_GPL(vhost_dev_has_owner); |
05c05351 | 526 | |
5ce995f3 JW |
527 | static void vhost_attach_mm(struct vhost_dev *dev) |
528 | { | |
529 | /* No owner, become one */ | |
530 | if (dev->use_worker) { | |
531 | dev->mm = get_task_mm(current); | |
532 | } else { | |
533 | /* vDPA device does not use worker thead, so there's | |
534 | * no need to hold the address space for mm. This help | |
535 | * to avoid deadlock in the case of mmap() which may | |
536 | * held the refcnt of the file and depends on release | |
537 | * method to remove vma. | |
538 | */ | |
539 | dev->mm = current->mm; | |
540 | mmgrab(dev->mm); | |
541 | } | |
542 | } | |
543 | ||
544 | static void vhost_detach_mm(struct vhost_dev *dev) | |
545 | { | |
546 | if (!dev->mm) | |
547 | return; | |
548 | ||
549 | if (dev->use_worker) | |
550 | mmput(dev->mm); | |
551 | else | |
552 | mmdrop(dev->mm); | |
553 | ||
554 | dev->mm = NULL; | |
555 | } | |
556 | ||
1a5f8090 MC |
557 | static void vhost_worker_free(struct vhost_dev *dev) |
558 | { | |
c011bb66 | 559 | if (!dev->worker) |
1a5f8090 MC |
560 | return; |
561 | ||
c011bb66 MC |
562 | WARN_ON(!llist_empty(&dev->worker->work_list)); |
563 | vhost_task_stop(dev->worker->vtsk); | |
564 | kfree(dev->worker); | |
565 | dev->worker = NULL; | |
1a5f8090 MC |
566 | } |
567 | ||
737bdb64 | 568 | static struct vhost_worker *vhost_worker_create(struct vhost_dev *dev) |
1a5f8090 | 569 | { |
c011bb66 | 570 | struct vhost_worker *worker; |
6e890c5d MC |
571 | struct vhost_task *vtsk; |
572 | char name[TASK_COMM_LEN]; | |
1a5f8090 | 573 | |
c011bb66 MC |
574 | worker = kzalloc(sizeof(*worker), GFP_KERNEL_ACCOUNT); |
575 | if (!worker) | |
737bdb64 | 576 | return NULL; |
c011bb66 | 577 | |
6e890c5d | 578 | snprintf(name, sizeof(name), "vhost-%d", current->pid); |
1a5f8090 | 579 | |
c011bb66 | 580 | vtsk = vhost_task_create(vhost_worker, worker, name); |
a284f09e | 581 | if (!vtsk) |
c011bb66 MC |
582 | goto free_worker; |
583 | ||
584 | init_llist_head(&worker->work_list); | |
585 | worker->kcov_handle = kcov_common_handle(); | |
586 | worker->vtsk = vtsk; | |
587 | /* | |
588 | * vsock can already try to queue so make sure llist and vtsk are both | |
589 | * set before vhost_work_queue sees dev->worker is set. | |
590 | */ | |
591 | smp_wmb(); | |
592 | dev->worker = worker; | |
1a5f8090 | 593 | |
6e890c5d | 594 | vhost_task_start(vtsk); |
737bdb64 | 595 | return worker; |
c011bb66 MC |
596 | |
597 | free_worker: | |
598 | kfree(worker); | |
737bdb64 | 599 | return NULL; |
1a5f8090 MC |
600 | } |
601 | ||
cef25866 MC |
602 | static int vhost_get_vq_from_user(struct vhost_dev *dev, void __user *argp, |
603 | struct vhost_virtqueue **vq, u32 *id) | |
604 | { | |
605 | u32 __user *idxp = argp; | |
606 | u32 idx; | |
607 | long r; | |
608 | ||
609 | r = get_user(idx, idxp); | |
610 | if (r < 0) | |
611 | return r; | |
612 | ||
613 | if (idx >= dev->nvqs) | |
614 | return -ENOBUFS; | |
615 | ||
616 | idx = array_index_nospec(idx, dev->nvqs); | |
617 | ||
618 | *vq = dev->vqs[idx]; | |
619 | *id = idx; | |
620 | return 0; | |
621 | } | |
622 | ||
3a4d5c94 | 623 | /* Caller should have device mutex */ |
54db63c2 | 624 | long vhost_dev_set_owner(struct vhost_dev *dev) |
3a4d5c94 | 625 | { |
737bdb64 MC |
626 | struct vhost_worker *worker; |
627 | int err, i; | |
d47effe1 | 628 | |
3a4d5c94 | 629 | /* Is there an owner already? */ |
05c05351 | 630 | if (vhost_dev_has_owner(dev)) { |
c23f3445 TH |
631 | err = -EBUSY; |
632 | goto err_mm; | |
633 | } | |
d47effe1 | 634 | |
5ce995f3 JW |
635 | vhost_attach_mm(dev); |
636 | ||
3e11c6eb MC |
637 | err = vhost_dev_alloc_iovecs(dev); |
638 | if (err) | |
639 | goto err_iovecs; | |
640 | ||
01fcb1cb | 641 | if (dev->use_worker) { |
3e11c6eb MC |
642 | /* |
643 | * This should be done last, because vsock can queue work | |
644 | * before VHOST_SET_OWNER so it simplifies the failure path | |
645 | * below since we don't have to worry about vsock queueing | |
646 | * while we free the worker. | |
647 | */ | |
737bdb64 MC |
648 | worker = vhost_worker_create(dev); |
649 | if (!worker) { | |
650 | err = -ENOMEM; | |
1a5f8090 | 651 | goto err_worker; |
737bdb64 MC |
652 | } |
653 | ||
654 | for (i = 0; i < dev->nvqs; i++) | |
655 | dev->vqs[i]->worker = worker; | |
01fcb1cb | 656 | } |
c23f3445 | 657 | |
3a4d5c94 | 658 | return 0; |
3e11c6eb | 659 | |
c23f3445 | 660 | err_worker: |
3e11c6eb MC |
661 | vhost_dev_free_iovecs(dev); |
662 | err_iovecs: | |
5ce995f3 | 663 | vhost_detach_mm(dev); |
c23f3445 TH |
664 | err_mm: |
665 | return err; | |
3a4d5c94 | 666 | } |
6ac1afbf | 667 | EXPORT_SYMBOL_GPL(vhost_dev_set_owner); |
3a4d5c94 | 668 | |
0bbe3066 JW |
669 | static struct vhost_iotlb *iotlb_alloc(void) |
670 | { | |
671 | return vhost_iotlb_alloc(max_iotlb_entries, | |
672 | VHOST_IOTLB_FLAG_RETIRE); | |
673 | } | |
674 | ||
675 | struct vhost_iotlb *vhost_dev_reset_owner_prepare(void) | |
a9709d68 | 676 | { |
0bbe3066 | 677 | return iotlb_alloc(); |
150b9e51 | 678 | } |
6ac1afbf | 679 | EXPORT_SYMBOL_GPL(vhost_dev_reset_owner_prepare); |
3a4d5c94 | 680 | |
150b9e51 | 681 | /* Caller should have device mutex */ |
0bbe3066 | 682 | void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_iotlb *umem) |
150b9e51 | 683 | { |
47283bef MT |
684 | int i; |
685 | ||
f6f93f75 | 686 | vhost_dev_cleanup(dev); |
3a4d5c94 | 687 | |
a9709d68 | 688 | dev->umem = umem; |
47283bef MT |
689 | /* We don't need VQ locks below since vhost_dev_cleanup makes sure |
690 | * VQs aren't running. | |
691 | */ | |
692 | for (i = 0; i < dev->nvqs; ++i) | |
a9709d68 | 693 | dev->vqs[i]->umem = umem; |
3a4d5c94 | 694 | } |
6ac1afbf | 695 | EXPORT_SYMBOL_GPL(vhost_dev_reset_owner); |
3a4d5c94 | 696 | |
b211616d | 697 | void vhost_dev_stop(struct vhost_dev *dev) |
bab632d6 MT |
698 | { |
699 | int i; | |
b211616d MT |
700 | |
701 | for (i = 0; i < dev->nvqs; ++i) { | |
6ca84326 | 702 | if (dev->vqs[i]->kick && dev->vqs[i]->handle_kick) |
3ab2e420 | 703 | vhost_poll_stop(&dev->vqs[i]->poll); |
bab632d6 | 704 | } |
6ca84326 | 705 | |
b2ffa407 | 706 | vhost_dev_flush(dev); |
bab632d6 | 707 | } |
6ac1afbf | 708 | EXPORT_SYMBOL_GPL(vhost_dev_stop); |
bab632d6 | 709 | |
9526f9a2 | 710 | void vhost_clear_msg(struct vhost_dev *dev) |
6b1e6cc7 JW |
711 | { |
712 | struct vhost_msg_node *node, *n; | |
713 | ||
714 | spin_lock(&dev->iotlb_lock); | |
715 | ||
716 | list_for_each_entry_safe(node, n, &dev->read_list, node) { | |
717 | list_del(&node->node); | |
718 | kfree(node); | |
719 | } | |
720 | ||
721 | list_for_each_entry_safe(node, n, &dev->pending_list, node) { | |
722 | list_del(&node->node); | |
723 | kfree(node); | |
724 | } | |
725 | ||
726 | spin_unlock(&dev->iotlb_lock); | |
727 | } | |
9526f9a2 | 728 | EXPORT_SYMBOL_GPL(vhost_clear_msg); |
6b1e6cc7 | 729 | |
f6f93f75 | 730 | void vhost_dev_cleanup(struct vhost_dev *dev) |
3a4d5c94 MT |
731 | { |
732 | int i; | |
d47effe1 | 733 | |
3a4d5c94 | 734 | for (i = 0; i < dev->nvqs; ++i) { |
3ab2e420 AH |
735 | if (dev->vqs[i]->error_ctx) |
736 | eventfd_ctx_put(dev->vqs[i]->error_ctx); | |
3ab2e420 AH |
737 | if (dev->vqs[i]->kick) |
738 | fput(dev->vqs[i]->kick); | |
265a0ad8 ZL |
739 | if (dev->vqs[i]->call_ctx.ctx) |
740 | eventfd_ctx_put(dev->vqs[i]->call_ctx.ctx); | |
3ab2e420 | 741 | vhost_vq_reset(dev, dev->vqs[i]); |
3a4d5c94 | 742 | } |
e0e9b406 | 743 | vhost_dev_free_iovecs(dev); |
3a4d5c94 MT |
744 | if (dev->log_ctx) |
745 | eventfd_ctx_put(dev->log_ctx); | |
746 | dev->log_ctx = NULL; | |
3a4d5c94 | 747 | /* No one will access memory at this point */ |
0bbe3066 | 748 | vhost_iotlb_free(dev->umem); |
a9709d68 | 749 | dev->umem = NULL; |
0bbe3066 | 750 | vhost_iotlb_free(dev->iotlb); |
6b1e6cc7 JW |
751 | dev->iotlb = NULL; |
752 | vhost_clear_msg(dev); | |
a9a08845 | 753 | wake_up_interruptible_poll(&dev->wait, EPOLLIN | EPOLLRDNORM); |
1a5f8090 | 754 | vhost_worker_free(dev); |
5ce995f3 | 755 | vhost_detach_mm(dev); |
3a4d5c94 | 756 | } |
6ac1afbf | 757 | EXPORT_SYMBOL_GPL(vhost_dev_cleanup); |
3a4d5c94 | 758 | |
ddd3d408 | 759 | static bool log_access_ok(void __user *log_base, u64 addr, unsigned long sz) |
3a4d5c94 MT |
760 | { |
761 | u64 a = addr / VHOST_PAGE_SIZE / 8; | |
d47effe1 | 762 | |
3a4d5c94 MT |
763 | /* Make sure 64 bit math will not overflow. */ |
764 | if (a > ULONG_MAX - (unsigned long)log_base || | |
765 | a + (unsigned long)log_base > ULONG_MAX) | |
ddd3d408 | 766 | return false; |
3a4d5c94 | 767 | |
96d4f267 | 768 | return access_ok(log_base + a, |
3a4d5c94 MT |
769 | (sz + VHOST_PAGE_SIZE * 8 - 1) / VHOST_PAGE_SIZE / 8); |
770 | } | |
771 | ||
f7ad318e | 772 | /* Make sure 64 bit math will not overflow. */ |
ec33d031 MT |
773 | static bool vhost_overflow(u64 uaddr, u64 size) |
774 | { | |
f7ad318e XY |
775 | if (uaddr > ULONG_MAX || size > ULONG_MAX) |
776 | return true; | |
777 | ||
778 | if (!size) | |
779 | return false; | |
780 | ||
781 | return uaddr > ULONG_MAX - size + 1; | |
ec33d031 MT |
782 | } |
783 | ||
3a4d5c94 | 784 | /* Caller should have vq mutex and device mutex. */ |
0bbe3066 | 785 | static bool vq_memory_access_ok(void __user *log_base, struct vhost_iotlb *umem, |
ddd3d408 | 786 | int log_all) |
3a4d5c94 | 787 | { |
0bbe3066 | 788 | struct vhost_iotlb_map *map; |
179b284e | 789 | |
a9709d68 | 790 | if (!umem) |
ddd3d408 | 791 | return false; |
179b284e | 792 | |
0bbe3066 JW |
793 | list_for_each_entry(map, &umem->list, link) { |
794 | unsigned long a = map->addr; | |
a9709d68 | 795 | |
0bbe3066 | 796 | if (vhost_overflow(map->addr, map->size)) |
ddd3d408 | 797 | return false; |
ec33d031 MT |
798 | |
799 | ||
0bbe3066 | 800 | if (!access_ok((void __user *)a, map->size)) |
ddd3d408 | 801 | return false; |
3a4d5c94 | 802 | else if (log_all && !log_access_ok(log_base, |
0bbe3066 JW |
803 | map->start, |
804 | map->size)) | |
ddd3d408 | 805 | return false; |
3a4d5c94 | 806 | } |
ddd3d408 | 807 | return true; |
3a4d5c94 MT |
808 | } |
809 | ||
f8894913 JW |
810 | static inline void __user *vhost_vq_meta_fetch(struct vhost_virtqueue *vq, |
811 | u64 addr, unsigned int size, | |
812 | int type) | |
813 | { | |
0bbe3066 | 814 | const struct vhost_iotlb_map *map = vq->meta_iotlb[type]; |
f8894913 | 815 | |
0bbe3066 | 816 | if (!map) |
f8894913 JW |
817 | return NULL; |
818 | ||
1b0be99f | 819 | return (void __user *)(uintptr_t)(map->addr + addr - map->start); |
f8894913 JW |
820 | } |
821 | ||
3a4d5c94 MT |
822 | /* Can we switch to this memory table? */ |
823 | /* Caller should have device mutex but not vq mutex */ | |
0bbe3066 | 824 | static bool memory_access_ok(struct vhost_dev *d, struct vhost_iotlb *umem, |
ddd3d408 | 825 | int log_all) |
3a4d5c94 MT |
826 | { |
827 | int i; | |
d47effe1 | 828 | |
3a4d5c94 | 829 | for (i = 0; i < d->nvqs; ++i) { |
ddd3d408 | 830 | bool ok; |
ea16c514 MT |
831 | bool log; |
832 | ||
3ab2e420 | 833 | mutex_lock(&d->vqs[i]->mutex); |
ea16c514 | 834 | log = log_all || vhost_has_feature(d->vqs[i], VHOST_F_LOG_ALL); |
3a4d5c94 | 835 | /* If ring is inactive, will check when it's enabled. */ |
3ab2e420 | 836 | if (d->vqs[i]->private_data) |
a9709d68 JW |
837 | ok = vq_memory_access_ok(d->vqs[i]->log_base, |
838 | umem, log); | |
3a4d5c94 | 839 | else |
ddd3d408 | 840 | ok = true; |
3ab2e420 | 841 | mutex_unlock(&d->vqs[i]->mutex); |
3a4d5c94 | 842 | if (!ok) |
ddd3d408 | 843 | return false; |
3a4d5c94 | 844 | } |
ddd3d408 | 845 | return true; |
3a4d5c94 MT |
846 | } |
847 | ||
6b1e6cc7 JW |
848 | static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, |
849 | struct iovec iov[], int iov_size, int access); | |
bfe2bc51 | 850 | |
72952cc0 | 851 | static int vhost_copy_to_user(struct vhost_virtqueue *vq, void __user *to, |
bfe2bc51 JW |
852 | const void *from, unsigned size) |
853 | { | |
6b1e6cc7 | 854 | int ret; |
bfe2bc51 | 855 | |
6b1e6cc7 JW |
856 | if (!vq->iotlb) |
857 | return __copy_to_user(to, from, size); | |
858 | else { | |
859 | /* This function should be called after iotlb | |
860 | * prefetch, which means we're sure that all vq | |
861 | * could be access through iotlb. So -EAGAIN should | |
862 | * not happen in this case. | |
863 | */ | |
6b1e6cc7 | 864 | struct iov_iter t; |
f8894913 JW |
865 | void __user *uaddr = vhost_vq_meta_fetch(vq, |
866 | (u64)(uintptr_t)to, size, | |
7ced6c98 | 867 | VHOST_ADDR_USED); |
f8894913 JW |
868 | |
869 | if (uaddr) | |
870 | return __copy_to_user(uaddr, from, size); | |
871 | ||
6b1e6cc7 JW |
872 | ret = translate_desc(vq, (u64)(uintptr_t)to, size, vq->iotlb_iov, |
873 | ARRAY_SIZE(vq->iotlb_iov), | |
874 | VHOST_ACCESS_WO); | |
875 | if (ret < 0) | |
876 | goto out; | |
de4eda9d | 877 | iov_iter_init(&t, ITER_DEST, vq->iotlb_iov, ret, size); |
6b1e6cc7 JW |
878 | ret = copy_to_iter(from, size, &t); |
879 | if (ret == size) | |
880 | ret = 0; | |
881 | } | |
882 | out: | |
883 | return ret; | |
884 | } | |
bfe2bc51 JW |
885 | |
886 | static int vhost_copy_from_user(struct vhost_virtqueue *vq, void *to, | |
72952cc0 | 887 | void __user *from, unsigned size) |
bfe2bc51 | 888 | { |
6b1e6cc7 JW |
889 | int ret; |
890 | ||
891 | if (!vq->iotlb) | |
892 | return __copy_from_user(to, from, size); | |
893 | else { | |
894 | /* This function should be called after iotlb | |
895 | * prefetch, which means we're sure that vq | |
896 | * could be access through iotlb. So -EAGAIN should | |
897 | * not happen in this case. | |
898 | */ | |
f8894913 JW |
899 | void __user *uaddr = vhost_vq_meta_fetch(vq, |
900 | (u64)(uintptr_t)from, size, | |
901 | VHOST_ADDR_DESC); | |
6b1e6cc7 | 902 | struct iov_iter f; |
f8894913 JW |
903 | |
904 | if (uaddr) | |
905 | return __copy_from_user(to, uaddr, size); | |
906 | ||
6b1e6cc7 JW |
907 | ret = translate_desc(vq, (u64)(uintptr_t)from, size, vq->iotlb_iov, |
908 | ARRAY_SIZE(vq->iotlb_iov), | |
909 | VHOST_ACCESS_RO); | |
910 | if (ret < 0) { | |
911 | vq_err(vq, "IOTLB translation failure: uaddr " | |
912 | "%p size 0x%llx\n", from, | |
913 | (unsigned long long) size); | |
914 | goto out; | |
915 | } | |
de4eda9d | 916 | iov_iter_init(&f, ITER_SOURCE, vq->iotlb_iov, ret, size); |
6b1e6cc7 JW |
917 | ret = copy_from_iter(to, size, &f); |
918 | if (ret == size) | |
919 | ret = 0; | |
920 | } | |
921 | ||
922 | out: | |
923 | return ret; | |
924 | } | |
925 | ||
f8894913 JW |
926 | static void __user *__vhost_get_user_slow(struct vhost_virtqueue *vq, |
927 | void __user *addr, unsigned int size, | |
928 | int type) | |
6b1e6cc7 JW |
929 | { |
930 | int ret; | |
931 | ||
6b1e6cc7 JW |
932 | ret = translate_desc(vq, (u64)(uintptr_t)addr, size, vq->iotlb_iov, |
933 | ARRAY_SIZE(vq->iotlb_iov), | |
934 | VHOST_ACCESS_RO); | |
935 | if (ret < 0) { | |
936 | vq_err(vq, "IOTLB translation failure: uaddr " | |
937 | "%p size 0x%llx\n", addr, | |
938 | (unsigned long long) size); | |
939 | return NULL; | |
940 | } | |
941 | ||
942 | if (ret != 1 || vq->iotlb_iov[0].iov_len != size) { | |
943 | vq_err(vq, "Non atomic userspace memory access: uaddr " | |
944 | "%p size 0x%llx\n", addr, | |
945 | (unsigned long long) size); | |
946 | return NULL; | |
947 | } | |
948 | ||
949 | return vq->iotlb_iov[0].iov_base; | |
950 | } | |
951 | ||
f8894913 JW |
952 | /* This function should be called after iotlb |
953 | * prefetch, which means we're sure that vq | |
954 | * could be access through iotlb. So -EAGAIN should | |
955 | * not happen in this case. | |
956 | */ | |
957 | static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq, | |
1b0be99f | 958 | void __user *addr, unsigned int size, |
f8894913 JW |
959 | int type) |
960 | { | |
961 | void __user *uaddr = vhost_vq_meta_fetch(vq, | |
962 | (u64)(uintptr_t)addr, size, type); | |
963 | if (uaddr) | |
964 | return uaddr; | |
965 | ||
966 | return __vhost_get_user_slow(vq, addr, size, type); | |
967 | } | |
968 | ||
969 | #define vhost_put_user(vq, x, ptr) \ | |
6b1e6cc7 | 970 | ({ \ |
002ef18e | 971 | int ret; \ |
6b1e6cc7 JW |
972 | if (!vq->iotlb) { \ |
973 | ret = __put_user(x, ptr); \ | |
974 | } else { \ | |
975 | __typeof__(ptr) to = \ | |
f8894913 JW |
976 | (__typeof__(ptr)) __vhost_get_user(vq, ptr, \ |
977 | sizeof(*ptr), VHOST_ADDR_USED); \ | |
6b1e6cc7 JW |
978 | if (to != NULL) \ |
979 | ret = __put_user(x, to); \ | |
980 | else \ | |
981 | ret = -EFAULT; \ | |
982 | } \ | |
983 | ret; \ | |
984 | }) | |
985 | ||
7b5d753e JW |
986 | static inline int vhost_put_avail_event(struct vhost_virtqueue *vq) |
987 | { | |
988 | return vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx), | |
989 | vhost_avail_event(vq)); | |
990 | } | |
991 | ||
992 | static inline int vhost_put_used(struct vhost_virtqueue *vq, | |
993 | struct vring_used_elem *head, int idx, | |
994 | int count) | |
995 | { | |
996 | return vhost_copy_to_user(vq, vq->used->ring + idx, head, | |
997 | count * sizeof(*head)); | |
998 | } | |
999 | ||
1000 | static inline int vhost_put_used_flags(struct vhost_virtqueue *vq) | |
1001 | ||
1002 | { | |
1003 | return vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags), | |
1004 | &vq->used->flags); | |
1005 | } | |
1006 | ||
1007 | static inline int vhost_put_used_idx(struct vhost_virtqueue *vq) | |
1008 | ||
1009 | { | |
1010 | return vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx), | |
1011 | &vq->used->idx); | |
1012 | } | |
1013 | ||
f8894913 | 1014 | #define vhost_get_user(vq, x, ptr, type) \ |
6b1e6cc7 JW |
1015 | ({ \ |
1016 | int ret; \ | |
1017 | if (!vq->iotlb) { \ | |
1018 | ret = __get_user(x, ptr); \ | |
1019 | } else { \ | |
1020 | __typeof__(ptr) from = \ | |
f8894913 JW |
1021 | (__typeof__(ptr)) __vhost_get_user(vq, ptr, \ |
1022 | sizeof(*ptr), \ | |
1023 | type); \ | |
6b1e6cc7 JW |
1024 | if (from != NULL) \ |
1025 | ret = __get_user(x, from); \ | |
1026 | else \ | |
1027 | ret = -EFAULT; \ | |
1028 | } \ | |
1029 | ret; \ | |
1030 | }) | |
1031 | ||
f8894913 JW |
1032 | #define vhost_get_avail(vq, x, ptr) \ |
1033 | vhost_get_user(vq, x, ptr, VHOST_ADDR_AVAIL) | |
1034 | ||
1035 | #define vhost_get_used(vq, x, ptr) \ | |
1036 | vhost_get_user(vq, x, ptr, VHOST_ADDR_USED) | |
1037 | ||
86a07da3 JW |
1038 | static void vhost_dev_lock_vqs(struct vhost_dev *d) |
1039 | { | |
1040 | int i = 0; | |
1041 | for (i = 0; i < d->nvqs; ++i) | |
1042 | mutex_lock_nested(&d->vqs[i]->mutex, i); | |
1043 | } | |
1044 | ||
1045 | static void vhost_dev_unlock_vqs(struct vhost_dev *d) | |
1046 | { | |
1047 | int i = 0; | |
1048 | for (i = 0; i < d->nvqs; ++i) | |
1049 | mutex_unlock(&d->vqs[i]->mutex); | |
1050 | } | |
1051 | ||
7b5d753e JW |
1052 | static inline int vhost_get_avail_idx(struct vhost_virtqueue *vq, |
1053 | __virtio16 *idx) | |
1054 | { | |
1055 | return vhost_get_avail(vq, *idx, &vq->avail->idx); | |
1056 | } | |
1057 | ||
1058 | static inline int vhost_get_avail_head(struct vhost_virtqueue *vq, | |
1059 | __virtio16 *head, int idx) | |
1060 | { | |
1061 | return vhost_get_avail(vq, *head, | |
1062 | &vq->avail->ring[idx & (vq->num - 1)]); | |
1063 | } | |
1064 | ||
1065 | static inline int vhost_get_avail_flags(struct vhost_virtqueue *vq, | |
1066 | __virtio16 *flags) | |
1067 | { | |
1068 | return vhost_get_avail(vq, *flags, &vq->avail->flags); | |
1069 | } | |
1070 | ||
1071 | static inline int vhost_get_used_event(struct vhost_virtqueue *vq, | |
1072 | __virtio16 *event) | |
1073 | { | |
1074 | return vhost_get_avail(vq, *event, vhost_used_event(vq)); | |
1075 | } | |
1076 | ||
1077 | static inline int vhost_get_used_idx(struct vhost_virtqueue *vq, | |
1078 | __virtio16 *idx) | |
1079 | { | |
1080 | return vhost_get_used(vq, *idx, &vq->used->idx); | |
1081 | } | |
1082 | ||
1083 | static inline int vhost_get_desc(struct vhost_virtqueue *vq, | |
1084 | struct vring_desc *desc, int idx) | |
1085 | { | |
1086 | return vhost_copy_from_user(vq, desc, vq->desc + idx, sizeof(*desc)); | |
1087 | } | |
1088 | ||
6b1e6cc7 JW |
1089 | static void vhost_iotlb_notify_vq(struct vhost_dev *d, |
1090 | struct vhost_iotlb_msg *msg) | |
1091 | { | |
1092 | struct vhost_msg_node *node, *n; | |
1093 | ||
1094 | spin_lock(&d->iotlb_lock); | |
1095 | ||
1096 | list_for_each_entry_safe(node, n, &d->pending_list, node) { | |
1097 | struct vhost_iotlb_msg *vq_msg = &node->msg.iotlb; | |
1098 | if (msg->iova <= vq_msg->iova && | |
2d66f997 | 1099 | msg->iova + msg->size - 1 >= vq_msg->iova && |
6b1e6cc7 JW |
1100 | vq_msg->type == VHOST_IOTLB_MISS) { |
1101 | vhost_poll_queue(&node->vq->poll); | |
1102 | list_del(&node->node); | |
1103 | kfree(node); | |
1104 | } | |
1105 | } | |
1106 | ||
1107 | spin_unlock(&d->iotlb_lock); | |
1108 | } | |
1109 | ||
ddd3d408 | 1110 | static bool umem_access_ok(u64 uaddr, u64 size, int access) |
6b1e6cc7 JW |
1111 | { |
1112 | unsigned long a = uaddr; | |
1113 | ||
ec33d031 MT |
1114 | /* Make sure 64 bit math will not overflow. */ |
1115 | if (vhost_overflow(uaddr, size)) | |
ddd3d408 | 1116 | return false; |
ec33d031 | 1117 | |
6b1e6cc7 | 1118 | if ((access & VHOST_ACCESS_RO) && |
96d4f267 | 1119 | !access_ok((void __user *)a, size)) |
ddd3d408 | 1120 | return false; |
6b1e6cc7 | 1121 | if ((access & VHOST_ACCESS_WO) && |
96d4f267 | 1122 | !access_ok((void __user *)a, size)) |
ddd3d408 SH |
1123 | return false; |
1124 | return true; | |
6b1e6cc7 JW |
1125 | } |
1126 | ||
91233ad7 | 1127 | static int vhost_process_iotlb_msg(struct vhost_dev *dev, u32 asid, |
72952cc0 | 1128 | struct vhost_iotlb_msg *msg) |
6b1e6cc7 JW |
1129 | { |
1130 | int ret = 0; | |
1131 | ||
91233ad7 GD |
1132 | if (asid != 0) |
1133 | return -EINVAL; | |
1134 | ||
1b15ad68 | 1135 | mutex_lock(&dev->mutex); |
86a07da3 | 1136 | vhost_dev_lock_vqs(dev); |
6b1e6cc7 JW |
1137 | switch (msg->type) { |
1138 | case VHOST_IOTLB_UPDATE: | |
1139 | if (!dev->iotlb) { | |
1140 | ret = -EFAULT; | |
1141 | break; | |
1142 | } | |
ddd3d408 | 1143 | if (!umem_access_ok(msg->uaddr, msg->size, msg->perm)) { |
6b1e6cc7 JW |
1144 | ret = -EFAULT; |
1145 | break; | |
1146 | } | |
f8894913 | 1147 | vhost_vq_meta_reset(dev); |
0bbe3066 JW |
1148 | if (vhost_iotlb_add_range(dev->iotlb, msg->iova, |
1149 | msg->iova + msg->size - 1, | |
1150 | msg->uaddr, msg->perm)) { | |
6b1e6cc7 JW |
1151 | ret = -ENOMEM; |
1152 | break; | |
1153 | } | |
1154 | vhost_iotlb_notify_vq(dev, msg); | |
1155 | break; | |
1156 | case VHOST_IOTLB_INVALIDATE: | |
6f3180af JW |
1157 | if (!dev->iotlb) { |
1158 | ret = -EFAULT; | |
1159 | break; | |
1160 | } | |
f8894913 | 1161 | vhost_vq_meta_reset(dev); |
0bbe3066 JW |
1162 | vhost_iotlb_del_range(dev->iotlb, msg->iova, |
1163 | msg->iova + msg->size - 1); | |
6b1e6cc7 JW |
1164 | break; |
1165 | default: | |
1166 | ret = -EINVAL; | |
1167 | break; | |
1168 | } | |
1169 | ||
86a07da3 | 1170 | vhost_dev_unlock_vqs(dev); |
1b15ad68 JW |
1171 | mutex_unlock(&dev->mutex); |
1172 | ||
6b1e6cc7 JW |
1173 | return ret; |
1174 | } | |
1175 | ssize_t vhost_chr_write_iter(struct vhost_dev *dev, | |
1176 | struct iov_iter *from) | |
1177 | { | |
429711ae JW |
1178 | struct vhost_iotlb_msg msg; |
1179 | size_t offset; | |
1180 | int type, ret; | |
91233ad7 | 1181 | u32 asid = 0; |
6b1e6cc7 | 1182 | |
429711ae | 1183 | ret = copy_from_iter(&type, sizeof(type), from); |
74ad7419 PT |
1184 | if (ret != sizeof(type)) { |
1185 | ret = -EINVAL; | |
6b1e6cc7 | 1186 | goto done; |
74ad7419 | 1187 | } |
6b1e6cc7 | 1188 | |
429711ae | 1189 | switch (type) { |
6b1e6cc7 | 1190 | case VHOST_IOTLB_MSG: |
429711ae JW |
1191 | /* There maybe a hole after type for V1 message type, |
1192 | * so skip it here. | |
1193 | */ | |
1194 | offset = offsetof(struct vhost_msg, iotlb) - sizeof(int); | |
1195 | break; | |
1196 | case VHOST_IOTLB_MSG_V2: | |
91233ad7 GD |
1197 | if (vhost_backend_has_feature(dev->vqs[0], |
1198 | VHOST_BACKEND_F_IOTLB_ASID)) { | |
1199 | ret = copy_from_iter(&asid, sizeof(asid), from); | |
1200 | if (ret != sizeof(asid)) { | |
1201 | ret = -EINVAL; | |
1202 | goto done; | |
1203 | } | |
aaca8373 | 1204 | offset = 0; |
91233ad7 GD |
1205 | } else |
1206 | offset = sizeof(__u32); | |
6b1e6cc7 JW |
1207 | break; |
1208 | default: | |
1209 | ret = -EINVAL; | |
429711ae | 1210 | goto done; |
6b1e6cc7 JW |
1211 | } |
1212 | ||
429711ae JW |
1213 | iov_iter_advance(from, offset); |
1214 | ret = copy_from_iter(&msg, sizeof(msg), from); | |
74ad7419 PT |
1215 | if (ret != sizeof(msg)) { |
1216 | ret = -EINVAL; | |
429711ae | 1217 | goto done; |
74ad7419 | 1218 | } |
792a4f2e | 1219 | |
95932ab2 JW |
1220 | if ((msg.type == VHOST_IOTLB_UPDATE || |
1221 | msg.type == VHOST_IOTLB_INVALIDATE) && | |
1222 | msg.size == 0) { | |
e2ae38cf AR |
1223 | ret = -EINVAL; |
1224 | goto done; | |
1225 | } | |
1226 | ||
792a4f2e | 1227 | if (dev->msg_handler) |
91233ad7 | 1228 | ret = dev->msg_handler(dev, asid, &msg); |
792a4f2e | 1229 | else |
91233ad7 | 1230 | ret = vhost_process_iotlb_msg(dev, asid, &msg); |
792a4f2e | 1231 | if (ret) { |
429711ae JW |
1232 | ret = -EFAULT; |
1233 | goto done; | |
1234 | } | |
1235 | ||
1236 | ret = (type == VHOST_IOTLB_MSG) ? sizeof(struct vhost_msg) : | |
1237 | sizeof(struct vhost_msg_v2); | |
6b1e6cc7 JW |
1238 | done: |
1239 | return ret; | |
1240 | } | |
1241 | EXPORT_SYMBOL(vhost_chr_write_iter); | |
1242 | ||
afc9a42b | 1243 | __poll_t vhost_chr_poll(struct file *file, struct vhost_dev *dev, |
6b1e6cc7 JW |
1244 | poll_table *wait) |
1245 | { | |
afc9a42b | 1246 | __poll_t mask = 0; |
6b1e6cc7 JW |
1247 | |
1248 | poll_wait(file, &dev->wait, wait); | |
1249 | ||
1250 | if (!list_empty(&dev->read_list)) | |
a9a08845 | 1251 | mask |= EPOLLIN | EPOLLRDNORM; |
6b1e6cc7 JW |
1252 | |
1253 | return mask; | |
1254 | } | |
1255 | EXPORT_SYMBOL(vhost_chr_poll); | |
1256 | ||
1257 | ssize_t vhost_chr_read_iter(struct vhost_dev *dev, struct iov_iter *to, | |
1258 | int noblock) | |
1259 | { | |
1260 | DEFINE_WAIT(wait); | |
1261 | struct vhost_msg_node *node; | |
1262 | ssize_t ret = 0; | |
1263 | unsigned size = sizeof(struct vhost_msg); | |
1264 | ||
1265 | if (iov_iter_count(to) < size) | |
1266 | return 0; | |
1267 | ||
1268 | while (1) { | |
1269 | if (!noblock) | |
1270 | prepare_to_wait(&dev->wait, &wait, | |
1271 | TASK_INTERRUPTIBLE); | |
1272 | ||
1273 | node = vhost_dequeue_msg(dev, &dev->read_list); | |
1274 | if (node) | |
1275 | break; | |
1276 | if (noblock) { | |
1277 | ret = -EAGAIN; | |
1278 | break; | |
1279 | } | |
1280 | if (signal_pending(current)) { | |
1281 | ret = -ERESTARTSYS; | |
1282 | break; | |
1283 | } | |
1284 | if (!dev->iotlb) { | |
1285 | ret = -EBADFD; | |
1286 | break; | |
1287 | } | |
1288 | ||
1289 | schedule(); | |
1290 | } | |
1291 | ||
1292 | if (!noblock) | |
1293 | finish_wait(&dev->wait, &wait); | |
1294 | ||
1295 | if (node) { | |
429711ae JW |
1296 | struct vhost_iotlb_msg *msg; |
1297 | void *start = &node->msg; | |
6b1e6cc7 | 1298 | |
429711ae JW |
1299 | switch (node->msg.type) { |
1300 | case VHOST_IOTLB_MSG: | |
1301 | size = sizeof(node->msg); | |
1302 | msg = &node->msg.iotlb; | |
1303 | break; | |
1304 | case VHOST_IOTLB_MSG_V2: | |
1305 | size = sizeof(node->msg_v2); | |
1306 | msg = &node->msg_v2.iotlb; | |
1307 | break; | |
1308 | default: | |
1309 | BUG(); | |
1310 | break; | |
1311 | } | |
1312 | ||
1313 | ret = copy_to_iter(start, size, to); | |
1314 | if (ret != size || msg->type != VHOST_IOTLB_MISS) { | |
6b1e6cc7 JW |
1315 | kfree(node); |
1316 | return ret; | |
1317 | } | |
6b1e6cc7 JW |
1318 | vhost_enqueue_msg(dev, &dev->pending_list, node); |
1319 | } | |
1320 | ||
1321 | return ret; | |
1322 | } | |
1323 | EXPORT_SYMBOL_GPL(vhost_chr_read_iter); | |
1324 | ||
1325 | static int vhost_iotlb_miss(struct vhost_virtqueue *vq, u64 iova, int access) | |
1326 | { | |
1327 | struct vhost_dev *dev = vq->dev; | |
1328 | struct vhost_msg_node *node; | |
1329 | struct vhost_iotlb_msg *msg; | |
429711ae | 1330 | bool v2 = vhost_backend_has_feature(vq, VHOST_BACKEND_F_IOTLB_MSG_V2); |
6b1e6cc7 | 1331 | |
429711ae | 1332 | node = vhost_new_msg(vq, v2 ? VHOST_IOTLB_MSG_V2 : VHOST_IOTLB_MSG); |
6b1e6cc7 JW |
1333 | if (!node) |
1334 | return -ENOMEM; | |
1335 | ||
429711ae JW |
1336 | if (v2) { |
1337 | node->msg_v2.type = VHOST_IOTLB_MSG_V2; | |
1338 | msg = &node->msg_v2.iotlb; | |
1339 | } else { | |
1340 | msg = &node->msg.iotlb; | |
1341 | } | |
1342 | ||
6b1e6cc7 JW |
1343 | msg->type = VHOST_IOTLB_MISS; |
1344 | msg->iova = iova; | |
1345 | msg->perm = access; | |
1346 | ||
1347 | vhost_enqueue_msg(dev, &dev->read_list, node); | |
1348 | ||
1349 | return 0; | |
bfe2bc51 JW |
1350 | } |
1351 | ||
ddd3d408 | 1352 | static bool vq_access_ok(struct vhost_virtqueue *vq, unsigned int num, |
a865e420 MT |
1353 | vring_desc_t __user *desc, |
1354 | vring_avail_t __user *avail, | |
1355 | vring_used_t __user *used) | |
6b1e6cc7 | 1356 | |
3a4d5c94 | 1357 | { |
0210a8db GK |
1358 | /* If an IOTLB device is present, the vring addresses are |
1359 | * GIOVAs. Access validation occurs at prefetch time. */ | |
1360 | if (vq->iotlb) | |
1361 | return true; | |
1362 | ||
4942e825 JW |
1363 | return access_ok(desc, vhost_get_desc_size(vq, num)) && |
1364 | access_ok(avail, vhost_get_avail_size(vq, num)) && | |
1365 | access_ok(used, vhost_get_used_size(vq, num)); | |
3a4d5c94 MT |
1366 | } |
1367 | ||
f8894913 | 1368 | static void vhost_vq_meta_update(struct vhost_virtqueue *vq, |
0bbe3066 | 1369 | const struct vhost_iotlb_map *map, |
f8894913 JW |
1370 | int type) |
1371 | { | |
1372 | int access = (type == VHOST_ADDR_USED) ? | |
1373 | VHOST_ACCESS_WO : VHOST_ACCESS_RO; | |
1374 | ||
0bbe3066 JW |
1375 | if (likely(map->perm & access)) |
1376 | vq->meta_iotlb[type] = map; | |
f8894913 JW |
1377 | } |
1378 | ||
ddd3d408 SH |
1379 | static bool iotlb_access_ok(struct vhost_virtqueue *vq, |
1380 | int access, u64 addr, u64 len, int type) | |
6b1e6cc7 | 1381 | { |
0bbe3066 JW |
1382 | const struct vhost_iotlb_map *map; |
1383 | struct vhost_iotlb *umem = vq->iotlb; | |
ca2c5b33 | 1384 | u64 s = 0, size, orig_addr = addr, last = addr + len - 1; |
f8894913 JW |
1385 | |
1386 | if (vhost_vq_meta_fetch(vq, addr, len, type)) | |
1387 | return true; | |
6b1e6cc7 JW |
1388 | |
1389 | while (len > s) { | |
0bbe3066 JW |
1390 | map = vhost_iotlb_itree_first(umem, addr, last); |
1391 | if (map == NULL || map->start > addr) { | |
6b1e6cc7 JW |
1392 | vhost_iotlb_miss(vq, addr, access); |
1393 | return false; | |
0bbe3066 | 1394 | } else if (!(map->perm & access)) { |
6b1e6cc7 JW |
1395 | /* Report the possible access violation by |
1396 | * request another translation from userspace. | |
1397 | */ | |
1398 | return false; | |
1399 | } | |
1400 | ||
0bbe3066 | 1401 | size = map->size - addr + map->start; |
f8894913 JW |
1402 | |
1403 | if (orig_addr == addr && size >= len) | |
0bbe3066 | 1404 | vhost_vq_meta_update(vq, map, type); |
f8894913 | 1405 | |
6b1e6cc7 JW |
1406 | s += size; |
1407 | addr += size; | |
1408 | } | |
1409 | ||
1410 | return true; | |
1411 | } | |
1412 | ||
9b5e830b | 1413 | int vq_meta_prefetch(struct vhost_virtqueue *vq) |
6b1e6cc7 | 1414 | { |
6b1e6cc7 JW |
1415 | unsigned int num = vq->num; |
1416 | ||
3d2c7d37 | 1417 | if (!vq->iotlb) |
6b1e6cc7 JW |
1418 | return 1; |
1419 | ||
0bbe3066 | 1420 | return iotlb_access_ok(vq, VHOST_MAP_RO, (u64)(uintptr_t)vq->desc, |
4942e825 | 1421 | vhost_get_desc_size(vq, num), VHOST_ADDR_DESC) && |
0bbe3066 | 1422 | iotlb_access_ok(vq, VHOST_MAP_RO, (u64)(uintptr_t)vq->avail, |
4942e825 | 1423 | vhost_get_avail_size(vq, num), |
f8894913 | 1424 | VHOST_ADDR_AVAIL) && |
0bbe3066 | 1425 | iotlb_access_ok(vq, VHOST_MAP_WO, (u64)(uintptr_t)vq->used, |
4942e825 | 1426 | vhost_get_used_size(vq, num), VHOST_ADDR_USED); |
6b1e6cc7 | 1427 | } |
9b5e830b | 1428 | EXPORT_SYMBOL_GPL(vq_meta_prefetch); |
6b1e6cc7 | 1429 | |
3a4d5c94 MT |
1430 | /* Can we log writes? */ |
1431 | /* Caller should have device mutex but not vq mutex */ | |
ddd3d408 | 1432 | bool vhost_log_access_ok(struct vhost_dev *dev) |
3a4d5c94 | 1433 | { |
a9709d68 | 1434 | return memory_access_ok(dev, dev->umem, 1); |
3a4d5c94 | 1435 | } |
6ac1afbf | 1436 | EXPORT_SYMBOL_GPL(vhost_log_access_ok); |
3a4d5c94 | 1437 | |
ab512251 GK |
1438 | static bool vq_log_used_access_ok(struct vhost_virtqueue *vq, |
1439 | void __user *log_base, | |
1440 | bool log_used, | |
1441 | u64 log_addr) | |
1442 | { | |
1443 | /* If an IOTLB device is present, log_addr is a GIOVA that | |
1444 | * will never be logged by log_used(). */ | |
1445 | if (vq->iotlb) | |
1446 | return true; | |
1447 | ||
1448 | return !log_used || log_access_ok(log_base, log_addr, | |
1449 | vhost_get_used_size(vq, vq->num)); | |
1450 | } | |
1451 | ||
3a4d5c94 MT |
1452 | /* Verify access for write logging. */ |
1453 | /* Caller should have vq mutex and device mutex */ | |
ddd3d408 SH |
1454 | static bool vq_log_access_ok(struct vhost_virtqueue *vq, |
1455 | void __user *log_base) | |
3a4d5c94 | 1456 | { |
a9709d68 | 1457 | return vq_memory_access_ok(log_base, vq->umem, |
ea16c514 | 1458 | vhost_has_feature(vq, VHOST_F_LOG_ALL)) && |
ab512251 | 1459 | vq_log_used_access_ok(vq, log_base, vq->log_used, vq->log_addr); |
3a4d5c94 MT |
1460 | } |
1461 | ||
1462 | /* Can we start vq? */ | |
1463 | /* Caller should have vq mutex and device mutex */ | |
ddd3d408 | 1464 | bool vhost_vq_access_ok(struct vhost_virtqueue *vq) |
3a4d5c94 | 1465 | { |
d14d2b78 | 1466 | if (!vq_log_access_ok(vq, vq->log_base)) |
ddd3d408 | 1467 | return false; |
d65026c6 | 1468 | |
d65026c6 | 1469 | return vq_access_ok(vq, vq->num, vq->desc, vq->avail, vq->used); |
3a4d5c94 | 1470 | } |
6ac1afbf | 1471 | EXPORT_SYMBOL_GPL(vhost_vq_access_ok); |
3a4d5c94 MT |
1472 | |
1473 | static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) | |
1474 | { | |
a9709d68 JW |
1475 | struct vhost_memory mem, *newmem; |
1476 | struct vhost_memory_region *region; | |
0bbe3066 | 1477 | struct vhost_iotlb *newumem, *oldumem; |
3a4d5c94 | 1478 | unsigned long size = offsetof(struct vhost_memory, regions); |
98f9ca0a | 1479 | int i; |
d47effe1 | 1480 | |
7ad9c9d2 TY |
1481 | if (copy_from_user(&mem, m, size)) |
1482 | return -EFAULT; | |
3a4d5c94 MT |
1483 | if (mem.padding) |
1484 | return -EOPNOTSUPP; | |
c9ce42f7 | 1485 | if (mem.nregions > max_mem_regions) |
3a4d5c94 | 1486 | return -E2BIG; |
b2303d7b MW |
1487 | newmem = kvzalloc(struct_size(newmem, regions, mem.nregions), |
1488 | GFP_KERNEL); | |
3a4d5c94 MT |
1489 | if (!newmem) |
1490 | return -ENOMEM; | |
1491 | ||
1492 | memcpy(newmem, &mem, size); | |
7ad9c9d2 | 1493 | if (copy_from_user(newmem->regions, m->regions, |
bf11d71a | 1494 | flex_array_size(newmem, regions, mem.nregions))) { |
bcfeacab | 1495 | kvfree(newmem); |
7ad9c9d2 | 1496 | return -EFAULT; |
3a4d5c94 MT |
1497 | } |
1498 | ||
0bbe3066 | 1499 | newumem = iotlb_alloc(); |
a9709d68 | 1500 | if (!newumem) { |
4de7255f | 1501 | kvfree(newmem); |
a9709d68 JW |
1502 | return -ENOMEM; |
1503 | } | |
1504 | ||
a9709d68 JW |
1505 | for (region = newmem->regions; |
1506 | region < newmem->regions + mem.nregions; | |
1507 | region++) { | |
0bbe3066 JW |
1508 | if (vhost_iotlb_add_range(newumem, |
1509 | region->guest_phys_addr, | |
1510 | region->guest_phys_addr + | |
1511 | region->memory_size - 1, | |
1512 | region->userspace_addr, | |
1513 | VHOST_MAP_RW)) | |
a9709d68 | 1514 | goto err; |
a02c3789 | 1515 | } |
a9709d68 JW |
1516 | |
1517 | if (!memory_access_ok(d, newumem, 0)) | |
1518 | goto err; | |
1519 | ||
1520 | oldumem = d->umem; | |
1521 | d->umem = newumem; | |
98f9ca0a | 1522 | |
47283bef | 1523 | /* All memory accesses are done under some VQ mutex. */ |
98f9ca0a MT |
1524 | for (i = 0; i < d->nvqs; ++i) { |
1525 | mutex_lock(&d->vqs[i]->mutex); | |
a9709d68 | 1526 | d->vqs[i]->umem = newumem; |
98f9ca0a MT |
1527 | mutex_unlock(&d->vqs[i]->mutex); |
1528 | } | |
a9709d68 JW |
1529 | |
1530 | kvfree(newmem); | |
0bbe3066 | 1531 | vhost_iotlb_free(oldumem); |
3a4d5c94 | 1532 | return 0; |
a9709d68 JW |
1533 | |
1534 | err: | |
0bbe3066 | 1535 | vhost_iotlb_free(newumem); |
a9709d68 JW |
1536 | kvfree(newmem); |
1537 | return -EFAULT; | |
3a4d5c94 MT |
1538 | } |
1539 | ||
feebcaea JW |
1540 | static long vhost_vring_set_num(struct vhost_dev *d, |
1541 | struct vhost_virtqueue *vq, | |
1542 | void __user *argp) | |
1543 | { | |
1544 | struct vhost_vring_state s; | |
1545 | ||
1546 | /* Resizing ring with an active backend? | |
1547 | * You don't want to do that. */ | |
1548 | if (vq->private_data) | |
1549 | return -EBUSY; | |
1550 | ||
1551 | if (copy_from_user(&s, argp, sizeof s)) | |
1552 | return -EFAULT; | |
1553 | ||
1554 | if (!s.num || s.num > 0xffff || (s.num & (s.num - 1))) | |
1555 | return -EINVAL; | |
1556 | vq->num = s.num; | |
1557 | ||
1558 | return 0; | |
1559 | } | |
1560 | ||
1561 | static long vhost_vring_set_addr(struct vhost_dev *d, | |
1562 | struct vhost_virtqueue *vq, | |
1563 | void __user *argp) | |
1564 | { | |
1565 | struct vhost_vring_addr a; | |
1566 | ||
1567 | if (copy_from_user(&a, argp, sizeof a)) | |
1568 | return -EFAULT; | |
1569 | if (a.flags & ~(0x1 << VHOST_VRING_F_LOG)) | |
1570 | return -EOPNOTSUPP; | |
1571 | ||
1572 | /* For 32bit, verify that the top 32bits of the user | |
1573 | data are set to zero. */ | |
1574 | if ((u64)(unsigned long)a.desc_user_addr != a.desc_user_addr || | |
1575 | (u64)(unsigned long)a.used_user_addr != a.used_user_addr || | |
1576 | (u64)(unsigned long)a.avail_user_addr != a.avail_user_addr) | |
1577 | return -EFAULT; | |
1578 | ||
1579 | /* Make sure it's safe to cast pointers to vring types. */ | |
1580 | BUILD_BUG_ON(__alignof__ *vq->avail > VRING_AVAIL_ALIGN_SIZE); | |
1581 | BUILD_BUG_ON(__alignof__ *vq->used > VRING_USED_ALIGN_SIZE); | |
1582 | if ((a.avail_user_addr & (VRING_AVAIL_ALIGN_SIZE - 1)) || | |
1583 | (a.used_user_addr & (VRING_USED_ALIGN_SIZE - 1)) || | |
1584 | (a.log_guest_addr & (VRING_USED_ALIGN_SIZE - 1))) | |
1585 | return -EINVAL; | |
1586 | ||
1587 | /* We only verify access here if backend is configured. | |
1588 | * If it is not, we don't as size might not have been setup. | |
1589 | * We will verify when backend is configured. */ | |
1590 | if (vq->private_data) { | |
1591 | if (!vq_access_ok(vq, vq->num, | |
1592 | (void __user *)(unsigned long)a.desc_user_addr, | |
1593 | (void __user *)(unsigned long)a.avail_user_addr, | |
1594 | (void __user *)(unsigned long)a.used_user_addr)) | |
1595 | return -EINVAL; | |
1596 | ||
1597 | /* Also validate log access for used ring if enabled. */ | |
ab512251 GK |
1598 | if (!vq_log_used_access_ok(vq, vq->log_base, |
1599 | a.flags & (0x1 << VHOST_VRING_F_LOG), | |
1600 | a.log_guest_addr)) | |
feebcaea JW |
1601 | return -EINVAL; |
1602 | } | |
1603 | ||
1604 | vq->log_used = !!(a.flags & (0x1 << VHOST_VRING_F_LOG)); | |
1605 | vq->desc = (void __user *)(unsigned long)a.desc_user_addr; | |
1606 | vq->avail = (void __user *)(unsigned long)a.avail_user_addr; | |
1607 | vq->log_addr = a.log_guest_addr; | |
1608 | vq->used = (void __user *)(unsigned long)a.used_user_addr; | |
1609 | ||
1610 | return 0; | |
1611 | } | |
1612 | ||
1613 | static long vhost_vring_set_num_addr(struct vhost_dev *d, | |
1614 | struct vhost_virtqueue *vq, | |
1615 | unsigned int ioctl, | |
1616 | void __user *argp) | |
1617 | { | |
1618 | long r; | |
1619 | ||
1620 | mutex_lock(&vq->mutex); | |
1621 | ||
1622 | switch (ioctl) { | |
1623 | case VHOST_SET_VRING_NUM: | |
1624 | r = vhost_vring_set_num(d, vq, argp); | |
1625 | break; | |
1626 | case VHOST_SET_VRING_ADDR: | |
1627 | r = vhost_vring_set_addr(d, vq, argp); | |
1628 | break; | |
1629 | default: | |
1630 | BUG(); | |
1631 | } | |
1632 | ||
1633 | mutex_unlock(&vq->mutex); | |
1634 | ||
1635 | return r; | |
1636 | } | |
26b36604 | 1637 | long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) |
3a4d5c94 | 1638 | { |
cecb46f1 AV |
1639 | struct file *eventfp, *filep = NULL; |
1640 | bool pollstart = false, pollstop = false; | |
3a4d5c94 | 1641 | struct eventfd_ctx *ctx = NULL; |
3a4d5c94 MT |
1642 | struct vhost_virtqueue *vq; |
1643 | struct vhost_vring_state s; | |
1644 | struct vhost_vring_file f; | |
3a4d5c94 MT |
1645 | u32 idx; |
1646 | long r; | |
1647 | ||
cef25866 | 1648 | r = vhost_get_vq_from_user(d, argp, &vq, &idx); |
3a4d5c94 MT |
1649 | if (r < 0) |
1650 | return r; | |
3a4d5c94 | 1651 | |
feebcaea JW |
1652 | if (ioctl == VHOST_SET_VRING_NUM || |
1653 | ioctl == VHOST_SET_VRING_ADDR) { | |
1654 | return vhost_vring_set_num_addr(d, vq, ioctl, argp); | |
1655 | } | |
1656 | ||
3a4d5c94 MT |
1657 | mutex_lock(&vq->mutex); |
1658 | ||
1659 | switch (ioctl) { | |
3a4d5c94 MT |
1660 | case VHOST_SET_VRING_BASE: |
1661 | /* Moving base with an active backend? | |
1662 | * You don't want to do that. */ | |
1663 | if (vq->private_data) { | |
1664 | r = -EBUSY; | |
1665 | break; | |
1666 | } | |
7ad9c9d2 TY |
1667 | if (copy_from_user(&s, argp, sizeof s)) { |
1668 | r = -EFAULT; | |
3a4d5c94 | 1669 | break; |
7ad9c9d2 | 1670 | } |
55d8122f SN |
1671 | if (vhost_has_feature(vq, VIRTIO_F_RING_PACKED)) { |
1672 | vq->last_avail_idx = s.num & 0xffff; | |
1673 | vq->last_used_idx = (s.num >> 16) & 0xffff; | |
1674 | } else { | |
1675 | if (s.num > 0xffff) { | |
1676 | r = -EINVAL; | |
1677 | break; | |
1678 | } | |
1679 | vq->last_avail_idx = s.num; | |
3a4d5c94 | 1680 | } |
3a4d5c94 MT |
1681 | /* Forget the cached index value. */ |
1682 | vq->avail_idx = vq->last_avail_idx; | |
1683 | break; | |
1684 | case VHOST_GET_VRING_BASE: | |
1685 | s.index = idx; | |
55d8122f SN |
1686 | if (vhost_has_feature(vq, VIRTIO_F_RING_PACKED)) |
1687 | s.num = (u32)vq->last_avail_idx | ((u32)vq->last_used_idx << 16); | |
1688 | else | |
1689 | s.num = vq->last_avail_idx; | |
7ad9c9d2 TY |
1690 | if (copy_to_user(argp, &s, sizeof s)) |
1691 | r = -EFAULT; | |
3a4d5c94 | 1692 | break; |
3a4d5c94 | 1693 | case VHOST_SET_VRING_KICK: |
7ad9c9d2 TY |
1694 | if (copy_from_user(&f, argp, sizeof f)) { |
1695 | r = -EFAULT; | |
3a4d5c94 | 1696 | break; |
7ad9c9d2 | 1697 | } |
e0136c16 | 1698 | eventfp = f.fd == VHOST_FILE_UNBIND ? NULL : eventfd_fget(f.fd); |
535297a6 MT |
1699 | if (IS_ERR(eventfp)) { |
1700 | r = PTR_ERR(eventfp); | |
1701 | break; | |
1702 | } | |
3a4d5c94 | 1703 | if (eventfp != vq->kick) { |
cecb46f1 AV |
1704 | pollstop = (filep = vq->kick) != NULL; |
1705 | pollstart = (vq->kick = eventfp) != NULL; | |
3a4d5c94 MT |
1706 | } else |
1707 | filep = eventfp; | |
1708 | break; | |
1709 | case VHOST_SET_VRING_CALL: | |
7ad9c9d2 TY |
1710 | if (copy_from_user(&f, argp, sizeof f)) { |
1711 | r = -EFAULT; | |
3a4d5c94 | 1712 | break; |
7ad9c9d2 | 1713 | } |
e0136c16 | 1714 | ctx = f.fd == VHOST_FILE_UNBIND ? NULL : eventfd_ctx_fdget(f.fd); |
e050c7d9 EB |
1715 | if (IS_ERR(ctx)) { |
1716 | r = PTR_ERR(ctx); | |
535297a6 MT |
1717 | break; |
1718 | } | |
265a0ad8 | 1719 | |
265a0ad8 | 1720 | swap(ctx, vq->call_ctx.ctx); |
3a4d5c94 MT |
1721 | break; |
1722 | case VHOST_SET_VRING_ERR: | |
7ad9c9d2 TY |
1723 | if (copy_from_user(&f, argp, sizeof f)) { |
1724 | r = -EFAULT; | |
3a4d5c94 | 1725 | break; |
7ad9c9d2 | 1726 | } |
e0136c16 | 1727 | ctx = f.fd == VHOST_FILE_UNBIND ? NULL : eventfd_ctx_fdget(f.fd); |
09f332a5 EB |
1728 | if (IS_ERR(ctx)) { |
1729 | r = PTR_ERR(ctx); | |
535297a6 MT |
1730 | break; |
1731 | } | |
09f332a5 | 1732 | swap(ctx, vq->error_ctx); |
3a4d5c94 | 1733 | break; |
2751c988 GK |
1734 | case VHOST_SET_VRING_ENDIAN: |
1735 | r = vhost_set_vring_endian(vq, argp); | |
1736 | break; | |
1737 | case VHOST_GET_VRING_ENDIAN: | |
1738 | r = vhost_get_vring_endian(vq, idx, argp); | |
1739 | break; | |
03088137 JW |
1740 | case VHOST_SET_VRING_BUSYLOOP_TIMEOUT: |
1741 | if (copy_from_user(&s, argp, sizeof(s))) { | |
1742 | r = -EFAULT; | |
1743 | break; | |
1744 | } | |
1745 | vq->busyloop_timeout = s.num; | |
1746 | break; | |
1747 | case VHOST_GET_VRING_BUSYLOOP_TIMEOUT: | |
1748 | s.index = idx; | |
1749 | s.num = vq->busyloop_timeout; | |
1750 | if (copy_to_user(argp, &s, sizeof(s))) | |
1751 | r = -EFAULT; | |
1752 | break; | |
3a4d5c94 MT |
1753 | default: |
1754 | r = -ENOIOCTLCMD; | |
1755 | } | |
1756 | ||
1757 | if (pollstop && vq->handle_kick) | |
1758 | vhost_poll_stop(&vq->poll); | |
1759 | ||
e050c7d9 | 1760 | if (!IS_ERR_OR_NULL(ctx)) |
3a4d5c94 MT |
1761 | eventfd_ctx_put(ctx); |
1762 | if (filep) | |
1763 | fput(filep); | |
1764 | ||
1765 | if (pollstart && vq->handle_kick) | |
2b8b328b | 1766 | r = vhost_poll_start(&vq->poll, vq->kick); |
3a4d5c94 MT |
1767 | |
1768 | mutex_unlock(&vq->mutex); | |
1769 | ||
1770 | if (pollstop && vq->handle_kick) | |
b2ffa407 | 1771 | vhost_dev_flush(vq->poll.dev); |
3a4d5c94 MT |
1772 | return r; |
1773 | } | |
6ac1afbf | 1774 | EXPORT_SYMBOL_GPL(vhost_vring_ioctl); |
3a4d5c94 | 1775 | |
759aba1e | 1776 | int vhost_init_device_iotlb(struct vhost_dev *d) |
6b1e6cc7 | 1777 | { |
0bbe3066 | 1778 | struct vhost_iotlb *niotlb, *oiotlb; |
6b1e6cc7 JW |
1779 | int i; |
1780 | ||
0bbe3066 | 1781 | niotlb = iotlb_alloc(); |
6b1e6cc7 JW |
1782 | if (!niotlb) |
1783 | return -ENOMEM; | |
1784 | ||
1785 | oiotlb = d->iotlb; | |
1786 | d->iotlb = niotlb; | |
1787 | ||
1788 | for (i = 0; i < d->nvqs; ++i) { | |
b13f9c63 JW |
1789 | struct vhost_virtqueue *vq = d->vqs[i]; |
1790 | ||
1791 | mutex_lock(&vq->mutex); | |
1792 | vq->iotlb = niotlb; | |
1793 | __vhost_vq_meta_reset(vq); | |
1794 | mutex_unlock(&vq->mutex); | |
6b1e6cc7 JW |
1795 | } |
1796 | ||
0bbe3066 | 1797 | vhost_iotlb_free(oiotlb); |
6b1e6cc7 JW |
1798 | |
1799 | return 0; | |
1800 | } | |
1801 | EXPORT_SYMBOL_GPL(vhost_init_device_iotlb); | |
1802 | ||
3a4d5c94 | 1803 | /* Caller must have device mutex */ |
935cdee7 | 1804 | long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) |
3a4d5c94 | 1805 | { |
d25cc43c | 1806 | struct eventfd_ctx *ctx; |
3a4d5c94 MT |
1807 | u64 p; |
1808 | long r; | |
1809 | int i, fd; | |
1810 | ||
1811 | /* If you are not the owner, you can become one */ | |
1812 | if (ioctl == VHOST_SET_OWNER) { | |
1813 | r = vhost_dev_set_owner(d); | |
1814 | goto done; | |
1815 | } | |
1816 | ||
1817 | /* You must be the owner to do anything else */ | |
1818 | r = vhost_dev_check_owner(d); | |
1819 | if (r) | |
1820 | goto done; | |
1821 | ||
1822 | switch (ioctl) { | |
1823 | case VHOST_SET_MEM_TABLE: | |
1824 | r = vhost_set_memory(d, argp); | |
1825 | break; | |
1826 | case VHOST_SET_LOG_BASE: | |
7ad9c9d2 TY |
1827 | if (copy_from_user(&p, argp, sizeof p)) { |
1828 | r = -EFAULT; | |
3a4d5c94 | 1829 | break; |
7ad9c9d2 | 1830 | } |
3a4d5c94 MT |
1831 | if ((u64)(unsigned long)p != p) { |
1832 | r = -EFAULT; | |
1833 | break; | |
1834 | } | |
1835 | for (i = 0; i < d->nvqs; ++i) { | |
1836 | struct vhost_virtqueue *vq; | |
1837 | void __user *base = (void __user *)(unsigned long)p; | |
3ab2e420 | 1838 | vq = d->vqs[i]; |
3a4d5c94 MT |
1839 | mutex_lock(&vq->mutex); |
1840 | /* If ring is inactive, will check when it's enabled. */ | |
ea16c514 | 1841 | if (vq->private_data && !vq_log_access_ok(vq, base)) |
3a4d5c94 MT |
1842 | r = -EFAULT; |
1843 | else | |
1844 | vq->log_base = base; | |
1845 | mutex_unlock(&vq->mutex); | |
1846 | } | |
1847 | break; | |
1848 | case VHOST_SET_LOG_FD: | |
1849 | r = get_user(fd, (int __user *)argp); | |
1850 | if (r < 0) | |
1851 | break; | |
e0136c16 | 1852 | ctx = fd == VHOST_FILE_UNBIND ? NULL : eventfd_ctx_fdget(fd); |
d25cc43c EB |
1853 | if (IS_ERR(ctx)) { |
1854 | r = PTR_ERR(ctx); | |
3a4d5c94 MT |
1855 | break; |
1856 | } | |
d25cc43c | 1857 | swap(ctx, d->log_ctx); |
3a4d5c94 | 1858 | for (i = 0; i < d->nvqs; ++i) { |
3ab2e420 AH |
1859 | mutex_lock(&d->vqs[i]->mutex); |
1860 | d->vqs[i]->log_ctx = d->log_ctx; | |
1861 | mutex_unlock(&d->vqs[i]->mutex); | |
3a4d5c94 MT |
1862 | } |
1863 | if (ctx) | |
1864 | eventfd_ctx_put(ctx); | |
3a4d5c94 MT |
1865 | break; |
1866 | default: | |
935cdee7 | 1867 | r = -ENOIOCTLCMD; |
3a4d5c94 MT |
1868 | break; |
1869 | } | |
1870 | done: | |
1871 | return r; | |
1872 | } | |
6ac1afbf | 1873 | EXPORT_SYMBOL_GPL(vhost_dev_ioctl); |
3a4d5c94 | 1874 | |
3a4d5c94 MT |
1875 | /* TODO: This is really inefficient. We need something like get_user() |
1876 | * (instruction directly accesses the data, with an exception table entry | |
ff61f079 | 1877 | * returning -EFAULT). See Documentation/arch/x86/exception-tables.rst. |
3a4d5c94 MT |
1878 | */ |
1879 | static int set_bit_to_user(int nr, void __user *addr) | |
1880 | { | |
1881 | unsigned long log = (unsigned long)addr; | |
1882 | struct page *page; | |
1883 | void *base; | |
1884 | int bit = nr + (log % PAGE_SIZE) * 8; | |
1885 | int r; | |
d47effe1 | 1886 | |
690623e1 | 1887 | r = pin_user_pages_fast(log, 1, FOLL_WRITE, &page); |
d6db3f5c | 1888 | if (r < 0) |
3a4d5c94 | 1889 | return r; |
d6db3f5c | 1890 | BUG_ON(r != 1); |
c6daa7ff | 1891 | base = kmap_atomic(page); |
3a4d5c94 | 1892 | set_bit(bit, base); |
c6daa7ff | 1893 | kunmap_atomic(base); |
690623e1 | 1894 | unpin_user_pages_dirty_lock(&page, 1, true); |
3a4d5c94 MT |
1895 | return 0; |
1896 | } | |
1897 | ||
1898 | static int log_write(void __user *log_base, | |
1899 | u64 write_address, u64 write_length) | |
1900 | { | |
28831ee6 | 1901 | u64 write_page = write_address / VHOST_PAGE_SIZE; |
3a4d5c94 | 1902 | int r; |
d47effe1 | 1903 | |
3a4d5c94 MT |
1904 | if (!write_length) |
1905 | return 0; | |
3bf9be40 | 1906 | write_length += write_address % VHOST_PAGE_SIZE; |
3a4d5c94 MT |
1907 | for (;;) { |
1908 | u64 base = (u64)(unsigned long)log_base; | |
28831ee6 MT |
1909 | u64 log = base + write_page / 8; |
1910 | int bit = write_page % 8; | |
3a4d5c94 MT |
1911 | if ((u64)(unsigned long)log != log) |
1912 | return -EFAULT; | |
1913 | r = set_bit_to_user(bit, (void __user *)(unsigned long)log); | |
1914 | if (r < 0) | |
1915 | return r; | |
1916 | if (write_length <= VHOST_PAGE_SIZE) | |
1917 | break; | |
1918 | write_length -= VHOST_PAGE_SIZE; | |
28831ee6 | 1919 | write_page += 1; |
3a4d5c94 MT |
1920 | } |
1921 | return r; | |
1922 | } | |
1923 | ||
cc5e7107 JW |
1924 | static int log_write_hva(struct vhost_virtqueue *vq, u64 hva, u64 len) |
1925 | { | |
0bbe3066 JW |
1926 | struct vhost_iotlb *umem = vq->umem; |
1927 | struct vhost_iotlb_map *u; | |
cc5e7107 JW |
1928 | u64 start, end, l, min; |
1929 | int r; | |
1930 | bool hit = false; | |
1931 | ||
1932 | while (len) { | |
1933 | min = len; | |
1934 | /* More than one GPAs can be mapped into a single HVA. So | |
1935 | * iterate all possible umems here to be safe. | |
1936 | */ | |
0bbe3066 JW |
1937 | list_for_each_entry(u, &umem->list, link) { |
1938 | if (u->addr > hva - 1 + len || | |
1939 | u->addr - 1 + u->size < hva) | |
cc5e7107 | 1940 | continue; |
0bbe3066 JW |
1941 | start = max(u->addr, hva); |
1942 | end = min(u->addr - 1 + u->size, hva - 1 + len); | |
cc5e7107 JW |
1943 | l = end - start + 1; |
1944 | r = log_write(vq->log_base, | |
0bbe3066 | 1945 | u->start + start - u->addr, |
cc5e7107 JW |
1946 | l); |
1947 | if (r < 0) | |
1948 | return r; | |
1949 | hit = true; | |
1950 | min = min(l, min); | |
1951 | } | |
1952 | ||
1953 | if (!hit) | |
1954 | return -EFAULT; | |
1955 | ||
1956 | len -= min; | |
1957 | hva += min; | |
1958 | } | |
1959 | ||
1960 | return 0; | |
1961 | } | |
1962 | ||
1963 | static int log_used(struct vhost_virtqueue *vq, u64 used_offset, u64 len) | |
1964 | { | |
5e5e8736 | 1965 | struct iovec *iov = vq->log_iov; |
cc5e7107 JW |
1966 | int i, ret; |
1967 | ||
1968 | if (!vq->iotlb) | |
1969 | return log_write(vq->log_base, vq->log_addr + used_offset, len); | |
1970 | ||
1971 | ret = translate_desc(vq, (uintptr_t)vq->used + used_offset, | |
1972 | len, iov, 64, VHOST_ACCESS_WO); | |
816db766 | 1973 | if (ret < 0) |
cc5e7107 JW |
1974 | return ret; |
1975 | ||
1976 | for (i = 0; i < ret; i++) { | |
1977 | ret = log_write_hva(vq, (uintptr_t)iov[i].iov_base, | |
1978 | iov[i].iov_len); | |
1979 | if (ret) | |
1980 | return ret; | |
1981 | } | |
1982 | ||
1983 | return 0; | |
1984 | } | |
1985 | ||
3a4d5c94 | 1986 | int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log, |
cc5e7107 | 1987 | unsigned int log_num, u64 len, struct iovec *iov, int count) |
3a4d5c94 MT |
1988 | { |
1989 | int i, r; | |
1990 | ||
1991 | /* Make sure data written is seen before log. */ | |
5659338c | 1992 | smp_wmb(); |
cc5e7107 JW |
1993 | |
1994 | if (vq->iotlb) { | |
1995 | for (i = 0; i < count; i++) { | |
1996 | r = log_write_hva(vq, (uintptr_t)iov[i].iov_base, | |
1997 | iov[i].iov_len); | |
1998 | if (r < 0) | |
1999 | return r; | |
2000 | } | |
2001 | return 0; | |
2002 | } | |
2003 | ||
3a4d5c94 MT |
2004 | for (i = 0; i < log_num; ++i) { |
2005 | u64 l = min(log[i].len, len); | |
2006 | r = log_write(vq->log_base, log[i].addr, l); | |
2007 | if (r < 0) | |
2008 | return r; | |
2009 | len -= l; | |
5786aee8 MT |
2010 | if (!len) { |
2011 | if (vq->log_ctx) | |
2012 | eventfd_signal(vq->log_ctx, 1); | |
3a4d5c94 | 2013 | return 0; |
5786aee8 | 2014 | } |
3a4d5c94 | 2015 | } |
3a4d5c94 MT |
2016 | /* Length written exceeds what we have stored. This is a bug. */ |
2017 | BUG(); | |
2018 | return 0; | |
2019 | } | |
6ac1afbf | 2020 | EXPORT_SYMBOL_GPL(vhost_log_write); |
3a4d5c94 | 2021 | |
2723feaa JW |
2022 | static int vhost_update_used_flags(struct vhost_virtqueue *vq) |
2023 | { | |
2024 | void __user *used; | |
7b5d753e | 2025 | if (vhost_put_used_flags(vq)) |
2723feaa JW |
2026 | return -EFAULT; |
2027 | if (unlikely(vq->log_used)) { | |
2028 | /* Make sure the flag is seen before log. */ | |
2029 | smp_wmb(); | |
2030 | /* Log used flag write. */ | |
2031 | used = &vq->used->flags; | |
cc5e7107 JW |
2032 | log_used(vq, (used - (void __user *)vq->used), |
2033 | sizeof vq->used->flags); | |
2723feaa JW |
2034 | if (vq->log_ctx) |
2035 | eventfd_signal(vq->log_ctx, 1); | |
2036 | } | |
2037 | return 0; | |
2038 | } | |
2039 | ||
4c809363 | 2040 | static int vhost_update_avail_event(struct vhost_virtqueue *vq) |
2723feaa | 2041 | { |
7b5d753e | 2042 | if (vhost_put_avail_event(vq)) |
2723feaa JW |
2043 | return -EFAULT; |
2044 | if (unlikely(vq->log_used)) { | |
2045 | void __user *used; | |
2046 | /* Make sure the event is seen before log. */ | |
2047 | smp_wmb(); | |
2048 | /* Log avail event write */ | |
2049 | used = vhost_avail_event(vq); | |
cc5e7107 JW |
2050 | log_used(vq, (used - (void __user *)vq->used), |
2051 | sizeof *vhost_avail_event(vq)); | |
2723feaa JW |
2052 | if (vq->log_ctx) |
2053 | eventfd_signal(vq->log_ctx, 1); | |
2054 | } | |
2055 | return 0; | |
2056 | } | |
2057 | ||
80f7d030 | 2058 | int vhost_vq_init_access(struct vhost_virtqueue *vq) |
2723feaa | 2059 | { |
3b1bbe89 | 2060 | __virtio16 last_used_idx; |
2723feaa | 2061 | int r; |
e1f33be9 GK |
2062 | bool is_le = vq->is_le; |
2063 | ||
cda8bba0 | 2064 | if (!vq->private_data) |
2723feaa | 2065 | return 0; |
2751c988 GK |
2066 | |
2067 | vhost_init_is_le(vq); | |
2723feaa JW |
2068 | |
2069 | r = vhost_update_used_flags(vq); | |
2070 | if (r) | |
e1f33be9 | 2071 | goto err; |
2723feaa | 2072 | vq->signalled_used_valid = false; |
6b1e6cc7 | 2073 | if (!vq->iotlb && |
96d4f267 | 2074 | !access_ok(&vq->used->idx, sizeof vq->used->idx)) { |
e1f33be9 GK |
2075 | r = -EFAULT; |
2076 | goto err; | |
2077 | } | |
7b5d753e | 2078 | r = vhost_get_used_idx(vq, &last_used_idx); |
6b1e6cc7 JW |
2079 | if (r) { |
2080 | vq_err(vq, "Can't access used idx at %p\n", | |
2081 | &vq->used->idx); | |
e1f33be9 | 2082 | goto err; |
6b1e6cc7 | 2083 | } |
3b1bbe89 | 2084 | vq->last_used_idx = vhost16_to_cpu(vq, last_used_idx); |
64f7f051 | 2085 | return 0; |
6b1e6cc7 | 2086 | |
e1f33be9 GK |
2087 | err: |
2088 | vq->is_le = is_le; | |
2089 | return r; | |
2723feaa | 2090 | } |
80f7d030 | 2091 | EXPORT_SYMBOL_GPL(vhost_vq_init_access); |
2723feaa | 2092 | |
47283bef | 2093 | static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, |
6b1e6cc7 | 2094 | struct iovec iov[], int iov_size, int access) |
3a4d5c94 | 2095 | { |
0bbe3066 | 2096 | const struct vhost_iotlb_map *map; |
6b1e6cc7 | 2097 | struct vhost_dev *dev = vq->dev; |
0bbe3066 | 2098 | struct vhost_iotlb *umem = dev->iotlb ? dev->iotlb : dev->umem; |
3a4d5c94 | 2099 | struct iovec *_iov; |
98047313 | 2100 | u64 s = 0, last = addr + len - 1; |
3a4d5c94 MT |
2101 | int ret = 0; |
2102 | ||
3a4d5c94 MT |
2103 | while ((u64)len > s) { |
2104 | u64 size; | |
7b3384fc | 2105 | if (unlikely(ret >= iov_size)) { |
3a4d5c94 MT |
2106 | ret = -ENOBUFS; |
2107 | break; | |
2108 | } | |
6b1e6cc7 | 2109 | |
98047313 | 2110 | map = vhost_iotlb_itree_first(umem, addr, last); |
0bbe3066 | 2111 | if (map == NULL || map->start > addr) { |
6b1e6cc7 JW |
2112 | if (umem != dev->iotlb) { |
2113 | ret = -EFAULT; | |
2114 | break; | |
2115 | } | |
2116 | ret = -EAGAIN; | |
2117 | break; | |
0bbe3066 | 2118 | } else if (!(map->perm & access)) { |
6b1e6cc7 | 2119 | ret = -EPERM; |
3a4d5c94 MT |
2120 | break; |
2121 | } | |
6b1e6cc7 | 2122 | |
3a4d5c94 | 2123 | _iov = iov + ret; |
0bbe3066 | 2124 | size = map->size - addr + map->start; |
bd97120f | 2125 | _iov->iov_len = min((u64)len - s, size); |
0d4a3f2a | 2126 | _iov->iov_base = (void __user *)(unsigned long) |
0bbe3066 | 2127 | (map->addr + addr - map->start); |
3a4d5c94 MT |
2128 | s += size; |
2129 | addr += size; | |
2130 | ++ret; | |
2131 | } | |
2132 | ||
6b1e6cc7 JW |
2133 | if (ret == -EAGAIN) |
2134 | vhost_iotlb_miss(vq, addr, access); | |
3a4d5c94 MT |
2135 | return ret; |
2136 | } | |
2137 | ||
2138 | /* Each buffer in the virtqueues is actually a chain of descriptors. This | |
2139 | * function returns the next descriptor in the chain, | |
2140 | * or -1U if we're at the end. */ | |
3b1bbe89 | 2141 | static unsigned next_desc(struct vhost_virtqueue *vq, struct vring_desc *desc) |
3a4d5c94 MT |
2142 | { |
2143 | unsigned int next; | |
2144 | ||
2145 | /* If this descriptor says it doesn't chain, we're done. */ | |
3b1bbe89 | 2146 | if (!(desc->flags & cpu_to_vhost16(vq, VRING_DESC_F_NEXT))) |
3a4d5c94 MT |
2147 | return -1U; |
2148 | ||
2149 | /* Check they're not leading us off end of descriptors. */ | |
3a5db0b1 | 2150 | next = vhost16_to_cpu(vq, READ_ONCE(desc->next)); |
3a4d5c94 MT |
2151 | return next; |
2152 | } | |
2153 | ||
47283bef | 2154 | static int get_indirect(struct vhost_virtqueue *vq, |
7b3384fc MT |
2155 | struct iovec iov[], unsigned int iov_size, |
2156 | unsigned int *out_num, unsigned int *in_num, | |
2157 | struct vhost_log *log, unsigned int *log_num, | |
2158 | struct vring_desc *indirect) | |
3a4d5c94 MT |
2159 | { |
2160 | struct vring_desc desc; | |
2161 | unsigned int i = 0, count, found = 0; | |
3b1bbe89 | 2162 | u32 len = vhost32_to_cpu(vq, indirect->len); |
aad9a1ce | 2163 | struct iov_iter from; |
6b1e6cc7 | 2164 | int ret, access; |
3a4d5c94 MT |
2165 | |
2166 | /* Sanity check */ | |
3b1bbe89 | 2167 | if (unlikely(len % sizeof desc)) { |
3a4d5c94 MT |
2168 | vq_err(vq, "Invalid length in indirect descriptor: " |
2169 | "len 0x%llx not multiple of 0x%zx\n", | |
3b1bbe89 | 2170 | (unsigned long long)len, |
3a4d5c94 MT |
2171 | sizeof desc); |
2172 | return -EINVAL; | |
2173 | } | |
2174 | ||
3b1bbe89 | 2175 | ret = translate_desc(vq, vhost64_to_cpu(vq, indirect->addr), len, vq->indirect, |
6b1e6cc7 | 2176 | UIO_MAXIOV, VHOST_ACCESS_RO); |
7b3384fc | 2177 | if (unlikely(ret < 0)) { |
6b1e6cc7 JW |
2178 | if (ret != -EAGAIN) |
2179 | vq_err(vq, "Translation failure %d in indirect.\n", ret); | |
3a4d5c94 MT |
2180 | return ret; |
2181 | } | |
de4eda9d | 2182 | iov_iter_init(&from, ITER_SOURCE, vq->indirect, ret, len); |
3b1bbe89 | 2183 | count = len / sizeof desc; |
3a4d5c94 MT |
2184 | /* Buffers are chained via a 16 bit next field, so |
2185 | * we can have at most 2^16 of these. */ | |
7b3384fc | 2186 | if (unlikely(count > USHRT_MAX + 1)) { |
3a4d5c94 MT |
2187 | vq_err(vq, "Indirect buffer length too big: %d\n", |
2188 | indirect->len); | |
2189 | return -E2BIG; | |
2190 | } | |
2191 | ||
2192 | do { | |
2193 | unsigned iov_count = *in_num + *out_num; | |
7b3384fc | 2194 | if (unlikely(++found > count)) { |
3a4d5c94 MT |
2195 | vq_err(vq, "Loop detected: last one at %u " |
2196 | "indirect size %u\n", | |
2197 | i, count); | |
2198 | return -EINVAL; | |
2199 | } | |
cbbd26b8 | 2200 | if (unlikely(!copy_from_iter_full(&desc, sizeof(desc), &from))) { |
3a4d5c94 | 2201 | vq_err(vq, "Failed indirect descriptor: idx %d, %zx\n", |
3b1bbe89 | 2202 | i, (size_t)vhost64_to_cpu(vq, indirect->addr) + i * sizeof desc); |
3a4d5c94 MT |
2203 | return -EINVAL; |
2204 | } | |
3b1bbe89 | 2205 | if (unlikely(desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_INDIRECT))) { |
3a4d5c94 | 2206 | vq_err(vq, "Nested indirect descriptor: idx %d, %zx\n", |
3b1bbe89 | 2207 | i, (size_t)vhost64_to_cpu(vq, indirect->addr) + i * sizeof desc); |
3a4d5c94 MT |
2208 | return -EINVAL; |
2209 | } | |
2210 | ||
6b1e6cc7 JW |
2211 | if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) |
2212 | access = VHOST_ACCESS_WO; | |
2213 | else | |
2214 | access = VHOST_ACCESS_RO; | |
2215 | ||
3b1bbe89 MT |
2216 | ret = translate_desc(vq, vhost64_to_cpu(vq, desc.addr), |
2217 | vhost32_to_cpu(vq, desc.len), iov + iov_count, | |
6b1e6cc7 | 2218 | iov_size - iov_count, access); |
7b3384fc | 2219 | if (unlikely(ret < 0)) { |
6b1e6cc7 JW |
2220 | if (ret != -EAGAIN) |
2221 | vq_err(vq, "Translation failure %d indirect idx %d\n", | |
2222 | ret, i); | |
3a4d5c94 MT |
2223 | return ret; |
2224 | } | |
2225 | /* If this is an input descriptor, increment that count. */ | |
6b1e6cc7 | 2226 | if (access == VHOST_ACCESS_WO) { |
3a4d5c94 | 2227 | *in_num += ret; |
060423bf | 2228 | if (unlikely(log && ret)) { |
3b1bbe89 MT |
2229 | log[*log_num].addr = vhost64_to_cpu(vq, desc.addr); |
2230 | log[*log_num].len = vhost32_to_cpu(vq, desc.len); | |
3a4d5c94 MT |
2231 | ++*log_num; |
2232 | } | |
2233 | } else { | |
2234 | /* If it's an output descriptor, they're all supposed | |
2235 | * to come before any input descriptors. */ | |
7b3384fc | 2236 | if (unlikely(*in_num)) { |
3a4d5c94 MT |
2237 | vq_err(vq, "Indirect descriptor " |
2238 | "has out after in: idx %d\n", i); | |
2239 | return -EINVAL; | |
2240 | } | |
2241 | *out_num += ret; | |
2242 | } | |
3b1bbe89 | 2243 | } while ((i = next_desc(vq, &desc)) != -1); |
3a4d5c94 MT |
2244 | return 0; |
2245 | } | |
2246 | ||
2247 | /* This looks in the virtqueue and for the first available buffer, and converts | |
2248 | * it to an iovec for convenient access. Since descriptors consist of some | |
2249 | * number of output then some number of input descriptors, it's actually two | |
2250 | * iovecs, but we pack them into one and note how many of each there were. | |
2251 | * | |
d5675bd2 MT |
2252 | * This function returns the descriptor number found, or vq->num (which is |
2253 | * never a valid descriptor number) if none was found. A negative code is | |
2254 | * returned on error. */ | |
47283bef | 2255 | int vhost_get_vq_desc(struct vhost_virtqueue *vq, |
d5675bd2 MT |
2256 | struct iovec iov[], unsigned int iov_size, |
2257 | unsigned int *out_num, unsigned int *in_num, | |
2258 | struct vhost_log *log, unsigned int *log_num) | |
3a4d5c94 MT |
2259 | { |
2260 | struct vring_desc desc; | |
2261 | unsigned int i, head, found = 0; | |
2262 | u16 last_avail_idx; | |
3b1bbe89 MT |
2263 | __virtio16 avail_idx; |
2264 | __virtio16 ring_head; | |
6b1e6cc7 | 2265 | int ret, access; |
3a4d5c94 MT |
2266 | |
2267 | /* Check it isn't doing very strange things with descriptor numbers. */ | |
2268 | last_avail_idx = vq->last_avail_idx; | |
3a4d5c94 | 2269 | |
e3b56cdd | 2270 | if (vq->avail_idx == vq->last_avail_idx) { |
7b5d753e | 2271 | if (unlikely(vhost_get_avail_idx(vq, &avail_idx))) { |
e3b56cdd JW |
2272 | vq_err(vq, "Failed to access avail idx at %p\n", |
2273 | &vq->avail->idx); | |
2274 | return -EFAULT; | |
2275 | } | |
2276 | vq->avail_idx = vhost16_to_cpu(vq, avail_idx); | |
3a4d5c94 | 2277 | |
e3b56cdd JW |
2278 | if (unlikely((u16)(vq->avail_idx - last_avail_idx) > vq->num)) { |
2279 | vq_err(vq, "Guest moved used index from %u to %u", | |
2280 | last_avail_idx, vq->avail_idx); | |
2281 | return -EFAULT; | |
2282 | } | |
2283 | ||
2284 | /* If there's nothing new since last we looked, return | |
2285 | * invalid. | |
2286 | */ | |
2287 | if (vq->avail_idx == last_avail_idx) | |
2288 | return vq->num; | |
3a4d5c94 | 2289 | |
e3b56cdd JW |
2290 | /* Only get avail ring entries after they have been |
2291 | * exposed by guest. | |
2292 | */ | |
2293 | smp_rmb(); | |
2294 | } | |
3a4d5c94 MT |
2295 | |
2296 | /* Grab the next descriptor number they're advertising, and increment | |
2297 | * the index we've seen. */ | |
7b5d753e | 2298 | if (unlikely(vhost_get_avail_head(vq, &ring_head, last_avail_idx))) { |
3a4d5c94 MT |
2299 | vq_err(vq, "Failed to read head: idx %d address %p\n", |
2300 | last_avail_idx, | |
2301 | &vq->avail->ring[last_avail_idx % vq->num]); | |
d5675bd2 | 2302 | return -EFAULT; |
3a4d5c94 MT |
2303 | } |
2304 | ||
3b1bbe89 MT |
2305 | head = vhost16_to_cpu(vq, ring_head); |
2306 | ||
3a4d5c94 | 2307 | /* If their number is silly, that's an error. */ |
7b3384fc | 2308 | if (unlikely(head >= vq->num)) { |
3a4d5c94 MT |
2309 | vq_err(vq, "Guest says index %u > %u is available", |
2310 | head, vq->num); | |
d5675bd2 | 2311 | return -EINVAL; |
3a4d5c94 MT |
2312 | } |
2313 | ||
2314 | /* When we start there are none of either input nor output. */ | |
2315 | *out_num = *in_num = 0; | |
2316 | if (unlikely(log)) | |
2317 | *log_num = 0; | |
2318 | ||
2319 | i = head; | |
2320 | do { | |
2321 | unsigned iov_count = *in_num + *out_num; | |
7b3384fc | 2322 | if (unlikely(i >= vq->num)) { |
3a4d5c94 MT |
2323 | vq_err(vq, "Desc index is %u > %u, head = %u", |
2324 | i, vq->num, head); | |
d5675bd2 | 2325 | return -EINVAL; |
3a4d5c94 | 2326 | } |
7b3384fc | 2327 | if (unlikely(++found > vq->num)) { |
3a4d5c94 MT |
2328 | vq_err(vq, "Loop detected: last one at %u " |
2329 | "vq size %u head %u\n", | |
2330 | i, vq->num, head); | |
d5675bd2 | 2331 | return -EINVAL; |
3a4d5c94 | 2332 | } |
7b5d753e | 2333 | ret = vhost_get_desc(vq, &desc, i); |
7b3384fc | 2334 | if (unlikely(ret)) { |
3a4d5c94 MT |
2335 | vq_err(vq, "Failed to get descriptor: idx %d addr %p\n", |
2336 | i, vq->desc + i); | |
d5675bd2 | 2337 | return -EFAULT; |
3a4d5c94 | 2338 | } |
3b1bbe89 | 2339 | if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_INDIRECT)) { |
47283bef | 2340 | ret = get_indirect(vq, iov, iov_size, |
3a4d5c94 MT |
2341 | out_num, in_num, |
2342 | log, log_num, &desc); | |
7b3384fc | 2343 | if (unlikely(ret < 0)) { |
6b1e6cc7 JW |
2344 | if (ret != -EAGAIN) |
2345 | vq_err(vq, "Failure detected " | |
2346 | "in indirect descriptor at idx %d\n", i); | |
d5675bd2 | 2347 | return ret; |
3a4d5c94 MT |
2348 | } |
2349 | continue; | |
2350 | } | |
2351 | ||
6b1e6cc7 JW |
2352 | if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) |
2353 | access = VHOST_ACCESS_WO; | |
2354 | else | |
2355 | access = VHOST_ACCESS_RO; | |
3b1bbe89 MT |
2356 | ret = translate_desc(vq, vhost64_to_cpu(vq, desc.addr), |
2357 | vhost32_to_cpu(vq, desc.len), iov + iov_count, | |
6b1e6cc7 | 2358 | iov_size - iov_count, access); |
7b3384fc | 2359 | if (unlikely(ret < 0)) { |
6b1e6cc7 JW |
2360 | if (ret != -EAGAIN) |
2361 | vq_err(vq, "Translation failure %d descriptor idx %d\n", | |
2362 | ret, i); | |
d5675bd2 | 2363 | return ret; |
3a4d5c94 | 2364 | } |
6b1e6cc7 | 2365 | if (access == VHOST_ACCESS_WO) { |
3a4d5c94 MT |
2366 | /* If this is an input descriptor, |
2367 | * increment that count. */ | |
2368 | *in_num += ret; | |
060423bf | 2369 | if (unlikely(log && ret)) { |
3b1bbe89 MT |
2370 | log[*log_num].addr = vhost64_to_cpu(vq, desc.addr); |
2371 | log[*log_num].len = vhost32_to_cpu(vq, desc.len); | |
3a4d5c94 MT |
2372 | ++*log_num; |
2373 | } | |
2374 | } else { | |
2375 | /* If it's an output descriptor, they're all supposed | |
2376 | * to come before any input descriptors. */ | |
7b3384fc | 2377 | if (unlikely(*in_num)) { |
3a4d5c94 MT |
2378 | vq_err(vq, "Descriptor has out after in: " |
2379 | "idx %d\n", i); | |
d5675bd2 | 2380 | return -EINVAL; |
3a4d5c94 MT |
2381 | } |
2382 | *out_num += ret; | |
2383 | } | |
3b1bbe89 | 2384 | } while ((i = next_desc(vq, &desc)) != -1); |
3a4d5c94 MT |
2385 | |
2386 | /* On success, increment avail index. */ | |
2387 | vq->last_avail_idx++; | |
8ea8cf89 MT |
2388 | |
2389 | /* Assume notifications from guest are disabled at this point, | |
2390 | * if they aren't we would need to update avail_event index. */ | |
2391 | BUG_ON(!(vq->used_flags & VRING_USED_F_NO_NOTIFY)); | |
3a4d5c94 MT |
2392 | return head; |
2393 | } | |
6ac1afbf | 2394 | EXPORT_SYMBOL_GPL(vhost_get_vq_desc); |
3a4d5c94 MT |
2395 | |
2396 | /* Reverse the effect of vhost_get_vq_desc. Useful for error handling. */ | |
8dd014ad | 2397 | void vhost_discard_vq_desc(struct vhost_virtqueue *vq, int n) |
3a4d5c94 | 2398 | { |
8dd014ad | 2399 | vq->last_avail_idx -= n; |
3a4d5c94 | 2400 | } |
6ac1afbf | 2401 | EXPORT_SYMBOL_GPL(vhost_discard_vq_desc); |
3a4d5c94 MT |
2402 | |
2403 | /* After we've used one of their buffers, we tell them about it. We'll then | |
2404 | * want to notify the guest, using eventfd. */ | |
2405 | int vhost_add_used(struct vhost_virtqueue *vq, unsigned int head, int len) | |
2406 | { | |
3b1bbe89 MT |
2407 | struct vring_used_elem heads = { |
2408 | cpu_to_vhost32(vq, head), | |
2409 | cpu_to_vhost32(vq, len) | |
2410 | }; | |
3a4d5c94 | 2411 | |
c49e4e57 | 2412 | return vhost_add_used_n(vq, &heads, 1); |
3a4d5c94 | 2413 | } |
6ac1afbf | 2414 | EXPORT_SYMBOL_GPL(vhost_add_used); |
3a4d5c94 | 2415 | |
8dd014ad DS |
2416 | static int __vhost_add_used_n(struct vhost_virtqueue *vq, |
2417 | struct vring_used_elem *heads, | |
2418 | unsigned count) | |
2419 | { | |
a865e420 | 2420 | vring_used_elem_t __user *used; |
8ea8cf89 | 2421 | u16 old, new; |
8dd014ad DS |
2422 | int start; |
2423 | ||
5fba13b5 | 2424 | start = vq->last_used_idx & (vq->num - 1); |
8dd014ad | 2425 | used = vq->used->ring + start; |
7b5d753e | 2426 | if (vhost_put_used(vq, heads, start, count)) { |
8dd014ad DS |
2427 | vq_err(vq, "Failed to write used"); |
2428 | return -EFAULT; | |
2429 | } | |
2430 | if (unlikely(vq->log_used)) { | |
2431 | /* Make sure data is seen before log. */ | |
2432 | smp_wmb(); | |
2433 | /* Log used ring entry write. */ | |
cc5e7107 JW |
2434 | log_used(vq, ((void __user *)used - (void __user *)vq->used), |
2435 | count * sizeof *used); | |
8dd014ad | 2436 | } |
8ea8cf89 MT |
2437 | old = vq->last_used_idx; |
2438 | new = (vq->last_used_idx += count); | |
2439 | /* If the driver never bothers to signal in a very long while, | |
2440 | * used index might wrap around. If that happens, invalidate | |
2441 | * signalled_used index we stored. TODO: make sure driver | |
2442 | * signals at least once in 2^16 and remove this. */ | |
2443 | if (unlikely((u16)(new - vq->signalled_used) < (u16)(new - old))) | |
2444 | vq->signalled_used_valid = false; | |
8dd014ad DS |
2445 | return 0; |
2446 | } | |
2447 | ||
2448 | /* After we've used one of their buffers, we tell them about it. We'll then | |
2449 | * want to notify the guest, using eventfd. */ | |
2450 | int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, | |
2451 | unsigned count) | |
2452 | { | |
2453 | int start, n, r; | |
2454 | ||
5fba13b5 | 2455 | start = vq->last_used_idx & (vq->num - 1); |
8dd014ad DS |
2456 | n = vq->num - start; |
2457 | if (n < count) { | |
2458 | r = __vhost_add_used_n(vq, heads, n); | |
2459 | if (r < 0) | |
2460 | return r; | |
2461 | heads += n; | |
2462 | count -= n; | |
2463 | } | |
2464 | r = __vhost_add_used_n(vq, heads, count); | |
2465 | ||
2466 | /* Make sure buffer is written before we update index. */ | |
2467 | smp_wmb(); | |
7b5d753e | 2468 | if (vhost_put_used_idx(vq)) { |
8dd014ad DS |
2469 | vq_err(vq, "Failed to increment used idx"); |
2470 | return -EFAULT; | |
2471 | } | |
2472 | if (unlikely(vq->log_used)) { | |
841df922 JW |
2473 | /* Make sure used idx is seen before log. */ |
2474 | smp_wmb(); | |
8dd014ad | 2475 | /* Log used index update. */ |
cc5e7107 JW |
2476 | log_used(vq, offsetof(struct vring_used, idx), |
2477 | sizeof vq->used->idx); | |
8dd014ad DS |
2478 | if (vq->log_ctx) |
2479 | eventfd_signal(vq->log_ctx, 1); | |
2480 | } | |
2481 | return r; | |
2482 | } | |
6ac1afbf | 2483 | EXPORT_SYMBOL_GPL(vhost_add_used_n); |
8dd014ad | 2484 | |
8ea8cf89 | 2485 | static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) |
3a4d5c94 | 2486 | { |
3b1bbe89 MT |
2487 | __u16 old, new; |
2488 | __virtio16 event; | |
8ea8cf89 | 2489 | bool v; |
8d65843c JW |
2490 | /* Flush out used index updates. This is paired |
2491 | * with the barrier that the Guest executes when enabling | |
2492 | * interrupts. */ | |
2493 | smp_mb(); | |
0d499356 | 2494 | |
ea16c514 | 2495 | if (vhost_has_feature(vq, VIRTIO_F_NOTIFY_ON_EMPTY) && |
8ea8cf89 MT |
2496 | unlikely(vq->avail_idx == vq->last_avail_idx)) |
2497 | return true; | |
2498 | ||
ea16c514 | 2499 | if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) { |
3b1bbe89 | 2500 | __virtio16 flags; |
7b5d753e | 2501 | if (vhost_get_avail_flags(vq, &flags)) { |
8ea8cf89 MT |
2502 | vq_err(vq, "Failed to get flags"); |
2503 | return true; | |
2504 | } | |
3b1bbe89 | 2505 | return !(flags & cpu_to_vhost16(vq, VRING_AVAIL_F_NO_INTERRUPT)); |
3a4d5c94 | 2506 | } |
8ea8cf89 MT |
2507 | old = vq->signalled_used; |
2508 | v = vq->signalled_used_valid; | |
2509 | new = vq->signalled_used = vq->last_used_idx; | |
2510 | vq->signalled_used_valid = true; | |
3a4d5c94 | 2511 | |
8ea8cf89 MT |
2512 | if (unlikely(!v)) |
2513 | return true; | |
3a4d5c94 | 2514 | |
7b5d753e | 2515 | if (vhost_get_used_event(vq, &event)) { |
8ea8cf89 MT |
2516 | vq_err(vq, "Failed to get used event idx"); |
2517 | return true; | |
2518 | } | |
8d65843c | 2519 | return vring_need_event(vhost16_to_cpu(vq, event), new, old); |
8ea8cf89 MT |
2520 | } |
2521 | ||
2522 | /* This actually signals the guest, using eventfd. */ | |
2523 | void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq) | |
2524 | { | |
3a4d5c94 | 2525 | /* Signal the Guest tell them we used something up. */ |
265a0ad8 ZL |
2526 | if (vq->call_ctx.ctx && vhost_notify(dev, vq)) |
2527 | eventfd_signal(vq->call_ctx.ctx, 1); | |
3a4d5c94 | 2528 | } |
6ac1afbf | 2529 | EXPORT_SYMBOL_GPL(vhost_signal); |
3a4d5c94 MT |
2530 | |
2531 | /* And here's the combo meal deal. Supersize me! */ | |
2532 | void vhost_add_used_and_signal(struct vhost_dev *dev, | |
2533 | struct vhost_virtqueue *vq, | |
2534 | unsigned int head, int len) | |
2535 | { | |
2536 | vhost_add_used(vq, head, len); | |
2537 | vhost_signal(dev, vq); | |
2538 | } | |
6ac1afbf | 2539 | EXPORT_SYMBOL_GPL(vhost_add_used_and_signal); |
3a4d5c94 | 2540 | |
8dd014ad DS |
2541 | /* multi-buffer version of vhost_add_used_and_signal */ |
2542 | void vhost_add_used_and_signal_n(struct vhost_dev *dev, | |
2543 | struct vhost_virtqueue *vq, | |
2544 | struct vring_used_elem *heads, unsigned count) | |
2545 | { | |
2546 | vhost_add_used_n(vq, heads, count); | |
2547 | vhost_signal(dev, vq); | |
2548 | } | |
6ac1afbf | 2549 | EXPORT_SYMBOL_GPL(vhost_add_used_and_signal_n); |
8dd014ad | 2550 | |
d4a60603 JW |
2551 | /* return true if we're sure that avaiable ring is empty */ |
2552 | bool vhost_vq_avail_empty(struct vhost_dev *dev, struct vhost_virtqueue *vq) | |
2553 | { | |
2554 | __virtio16 avail_idx; | |
2555 | int r; | |
2556 | ||
275bf960 JW |
2557 | if (vq->avail_idx != vq->last_avail_idx) |
2558 | return false; | |
2559 | ||
7b5d753e | 2560 | r = vhost_get_avail_idx(vq, &avail_idx); |
275bf960 | 2561 | if (unlikely(r)) |
d4a60603 | 2562 | return false; |
275bf960 | 2563 | vq->avail_idx = vhost16_to_cpu(vq, avail_idx); |
d4a60603 | 2564 | |
275bf960 | 2565 | return vq->avail_idx == vq->last_avail_idx; |
d4a60603 JW |
2566 | } |
2567 | EXPORT_SYMBOL_GPL(vhost_vq_avail_empty); | |
2568 | ||
3a4d5c94 | 2569 | /* OK, now we need to know about added descriptors. */ |
8ea8cf89 | 2570 | bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) |
3a4d5c94 | 2571 | { |
3b1bbe89 | 2572 | __virtio16 avail_idx; |
3a4d5c94 | 2573 | int r; |
d47effe1 | 2574 | |
3a4d5c94 MT |
2575 | if (!(vq->used_flags & VRING_USED_F_NO_NOTIFY)) |
2576 | return false; | |
2577 | vq->used_flags &= ~VRING_USED_F_NO_NOTIFY; | |
ea16c514 | 2578 | if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) { |
2723feaa | 2579 | r = vhost_update_used_flags(vq); |
8ea8cf89 MT |
2580 | if (r) { |
2581 | vq_err(vq, "Failed to enable notification at %p: %d\n", | |
2582 | &vq->used->flags, r); | |
2583 | return false; | |
2584 | } | |
2585 | } else { | |
4c809363 | 2586 | r = vhost_update_avail_event(vq); |
8ea8cf89 MT |
2587 | if (r) { |
2588 | vq_err(vq, "Failed to update avail event index at %p: %d\n", | |
2589 | vhost_avail_event(vq), r); | |
2590 | return false; | |
2591 | } | |
2592 | } | |
3a4d5c94 MT |
2593 | /* They could have slipped one in as we were doing that: make |
2594 | * sure it's written, then check again. */ | |
5659338c | 2595 | smp_mb(); |
7b5d753e | 2596 | r = vhost_get_avail_idx(vq, &avail_idx); |
3a4d5c94 MT |
2597 | if (r) { |
2598 | vq_err(vq, "Failed to check avail idx at %p: %d\n", | |
2599 | &vq->avail->idx, r); | |
2600 | return false; | |
2601 | } | |
d3bb267b | 2602 | vq->avail_idx = vhost16_to_cpu(vq, avail_idx); |
3a4d5c94 | 2603 | |
d3bb267b | 2604 | return vq->avail_idx != vq->last_avail_idx; |
3a4d5c94 | 2605 | } |
6ac1afbf | 2606 | EXPORT_SYMBOL_GPL(vhost_enable_notify); |
3a4d5c94 MT |
2607 | |
2608 | /* We don't need to be notified again. */ | |
8ea8cf89 | 2609 | void vhost_disable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) |
3a4d5c94 MT |
2610 | { |
2611 | int r; | |
d47effe1 | 2612 | |
3a4d5c94 MT |
2613 | if (vq->used_flags & VRING_USED_F_NO_NOTIFY) |
2614 | return; | |
2615 | vq->used_flags |= VRING_USED_F_NO_NOTIFY; | |
ea16c514 | 2616 | if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) { |
2723feaa | 2617 | r = vhost_update_used_flags(vq); |
8ea8cf89 | 2618 | if (r) |
ae6961de | 2619 | vq_err(vq, "Failed to disable notification at %p: %d\n", |
8ea8cf89 MT |
2620 | &vq->used->flags, r); |
2621 | } | |
3a4d5c94 | 2622 | } |
6ac1afbf AH |
2623 | EXPORT_SYMBOL_GPL(vhost_disable_notify); |
2624 | ||
6b1e6cc7 JW |
2625 | /* Create a new message. */ |
2626 | struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type) | |
2627 | { | |
4d8df0f5 PB |
2628 | /* Make sure all padding within the structure is initialized. */ |
2629 | struct vhost_msg_node *node = kzalloc(sizeof(*node), GFP_KERNEL); | |
6b1e6cc7 JW |
2630 | if (!node) |
2631 | return NULL; | |
670ae9ca | 2632 | |
6b1e6cc7 JW |
2633 | node->vq = vq; |
2634 | node->msg.type = type; | |
2635 | return node; | |
2636 | } | |
2637 | EXPORT_SYMBOL_GPL(vhost_new_msg); | |
2638 | ||
2639 | void vhost_enqueue_msg(struct vhost_dev *dev, struct list_head *head, | |
2640 | struct vhost_msg_node *node) | |
2641 | { | |
2642 | spin_lock(&dev->iotlb_lock); | |
2643 | list_add_tail(&node->node, head); | |
2644 | spin_unlock(&dev->iotlb_lock); | |
2645 | ||
a9a08845 | 2646 | wake_up_interruptible_poll(&dev->wait, EPOLLIN | EPOLLRDNORM); |
6b1e6cc7 JW |
2647 | } |
2648 | EXPORT_SYMBOL_GPL(vhost_enqueue_msg); | |
2649 | ||
2650 | struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev, | |
2651 | struct list_head *head) | |
2652 | { | |
2653 | struct vhost_msg_node *node = NULL; | |
2654 | ||
2655 | spin_lock(&dev->iotlb_lock); | |
2656 | if (!list_empty(head)) { | |
2657 | node = list_first_entry(head, struct vhost_msg_node, | |
2658 | node); | |
2659 | list_del(&node->node); | |
2660 | } | |
2661 | spin_unlock(&dev->iotlb_lock); | |
2662 | ||
2663 | return node; | |
2664 | } | |
2665 | EXPORT_SYMBOL_GPL(vhost_dequeue_msg); | |
2666 | ||
460f7ce1 JW |
2667 | void vhost_set_backend_features(struct vhost_dev *dev, u64 features) |
2668 | { | |
2669 | struct vhost_virtqueue *vq; | |
2670 | int i; | |
2671 | ||
2672 | mutex_lock(&dev->mutex); | |
2673 | for (i = 0; i < dev->nvqs; ++i) { | |
2674 | vq = dev->vqs[i]; | |
2675 | mutex_lock(&vq->mutex); | |
2676 | vq->acked_backend_features = features; | |
2677 | mutex_unlock(&vq->mutex); | |
2678 | } | |
2679 | mutex_unlock(&dev->mutex); | |
2680 | } | |
2681 | EXPORT_SYMBOL_GPL(vhost_set_backend_features); | |
6b1e6cc7 | 2682 | |
6ac1afbf AH |
2683 | static int __init vhost_init(void) |
2684 | { | |
2685 | return 0; | |
2686 | } | |
2687 | ||
2688 | static void __exit vhost_exit(void) | |
2689 | { | |
2690 | } | |
2691 | ||
2692 | module_init(vhost_init); | |
2693 | module_exit(vhost_exit); | |
2694 | ||
2695 | MODULE_VERSION("0.0.1"); | |
2696 | MODULE_LICENSE("GPL v2"); | |
2697 | MODULE_AUTHOR("Michael S. Tsirkin"); | |
2698 | MODULE_DESCRIPTION("Host kernel accelerator for virtio"); |