Commit | Line | Data |
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fd534e9b | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
0a8a69dd RR |
2 | /* Virtio ring implementation. |
3 | * | |
4 | * Copyright 2007 Rusty Russell IBM Corporation | |
0a8a69dd RR |
5 | */ |
6 | #include <linux/virtio.h> | |
7 | #include <linux/virtio_ring.h> | |
e34f8725 | 8 | #include <linux/virtio_config.h> |
0a8a69dd | 9 | #include <linux/device.h> |
5a0e3ad6 | 10 | #include <linux/slab.h> |
b5a2c4f1 | 11 | #include <linux/module.h> |
e93300b1 | 12 | #include <linux/hrtimer.h> |
780bc790 | 13 | #include <linux/dma-mapping.h> |
88938359 | 14 | #include <linux/kmsan.h> |
f8ce7263 | 15 | #include <linux/spinlock.h> |
78fe3987 | 16 | #include <xen/xen.h> |
0a8a69dd RR |
17 | |
18 | #ifdef DEBUG | |
19 | /* For development, we want to crash whenever the ring is screwed. */ | |
9499f5e7 RR |
20 | #define BAD_RING(_vq, fmt, args...) \ |
21 | do { \ | |
22 | dev_err(&(_vq)->vq.vdev->dev, \ | |
23 | "%s:"fmt, (_vq)->vq.name, ##args); \ | |
24 | BUG(); \ | |
25 | } while (0) | |
c5f841f1 RR |
26 | /* Caller is supposed to guarantee no reentry. */ |
27 | #define START_USE(_vq) \ | |
28 | do { \ | |
29 | if ((_vq)->in_use) \ | |
9499f5e7 RR |
30 | panic("%s:in_use = %i\n", \ |
31 | (_vq)->vq.name, (_vq)->in_use); \ | |
c5f841f1 | 32 | (_vq)->in_use = __LINE__; \ |
9499f5e7 | 33 | } while (0) |
3a35ce7d | 34 | #define END_USE(_vq) \ |
97a545ab | 35 | do { BUG_ON(!(_vq)->in_use); (_vq)->in_use = 0; } while(0) |
4d6a105e TB |
36 | #define LAST_ADD_TIME_UPDATE(_vq) \ |
37 | do { \ | |
38 | ktime_t now = ktime_get(); \ | |
39 | \ | |
40 | /* No kick or get, with .1 second between? Warn. */ \ | |
41 | if ((_vq)->last_add_time_valid) \ | |
42 | WARN_ON(ktime_to_ms(ktime_sub(now, \ | |
43 | (_vq)->last_add_time)) > 100); \ | |
44 | (_vq)->last_add_time = now; \ | |
45 | (_vq)->last_add_time_valid = true; \ | |
46 | } while (0) | |
47 | #define LAST_ADD_TIME_CHECK(_vq) \ | |
48 | do { \ | |
49 | if ((_vq)->last_add_time_valid) { \ | |
50 | WARN_ON(ktime_to_ms(ktime_sub(ktime_get(), \ | |
51 | (_vq)->last_add_time)) > 100); \ | |
52 | } \ | |
53 | } while (0) | |
54 | #define LAST_ADD_TIME_INVALID(_vq) \ | |
55 | ((_vq)->last_add_time_valid = false) | |
0a8a69dd | 56 | #else |
9499f5e7 RR |
57 | #define BAD_RING(_vq, fmt, args...) \ |
58 | do { \ | |
59 | dev_err(&_vq->vq.vdev->dev, \ | |
60 | "%s:"fmt, (_vq)->vq.name, ##args); \ | |
61 | (_vq)->broken = true; \ | |
62 | } while (0) | |
0a8a69dd RR |
63 | #define START_USE(vq) |
64 | #define END_USE(vq) | |
4d6a105e TB |
65 | #define LAST_ADD_TIME_UPDATE(vq) |
66 | #define LAST_ADD_TIME_CHECK(vq) | |
67 | #define LAST_ADD_TIME_INVALID(vq) | |
0a8a69dd RR |
68 | #endif |
69 | ||
cbeedb72 | 70 | struct vring_desc_state_split { |
780bc790 AL |
71 | void *data; /* Data for callback. */ |
72 | struct vring_desc *indir_desc; /* Indirect descriptor, if any. */ | |
73 | }; | |
74 | ||
1ce9e605 TB |
75 | struct vring_desc_state_packed { |
76 | void *data; /* Data for callback. */ | |
77 | struct vring_packed_desc *indir_desc; /* Indirect descriptor, if any. */ | |
78 | u16 num; /* Descriptor list length. */ | |
1ce9e605 TB |
79 | u16 last; /* The last desc state in a list. */ |
80 | }; | |
81 | ||
1f28750f | 82 | struct vring_desc_extra { |
ef5c366f JW |
83 | dma_addr_t addr; /* Descriptor DMA addr. */ |
84 | u32 len; /* Descriptor length. */ | |
1ce9e605 | 85 | u16 flags; /* Descriptor flags. */ |
aeef9b47 | 86 | u16 next; /* The next desc state in a list. */ |
1ce9e605 TB |
87 | }; |
88 | ||
d76136e4 XZ |
89 | struct vring_virtqueue_split { |
90 | /* Actual memory layout for this queue. */ | |
91 | struct vring vring; | |
92 | ||
93 | /* Last written value to avail->flags */ | |
94 | u16 avail_flags_shadow; | |
95 | ||
96 | /* | |
97 | * Last written value to avail->idx in | |
98 | * guest byte order. | |
99 | */ | |
100 | u16 avail_idx_shadow; | |
101 | ||
102 | /* Per-descriptor state. */ | |
103 | struct vring_desc_state_split *desc_state; | |
104 | struct vring_desc_extra *desc_extra; | |
105 | ||
106 | /* DMA address and size information */ | |
107 | dma_addr_t queue_dma_addr; | |
108 | size_t queue_size_in_bytes; | |
af36b16f XZ |
109 | |
110 | /* | |
111 | * The parameters for creating vrings are reserved for creating new | |
112 | * vring. | |
113 | */ | |
114 | u32 vring_align; | |
115 | bool may_reduce_num; | |
d76136e4 XZ |
116 | }; |
117 | ||
118 | struct vring_virtqueue_packed { | |
119 | /* Actual memory layout for this queue. */ | |
120 | struct { | |
121 | unsigned int num; | |
122 | struct vring_packed_desc *desc; | |
123 | struct vring_packed_desc_event *driver; | |
124 | struct vring_packed_desc_event *device; | |
125 | } vring; | |
126 | ||
127 | /* Driver ring wrap counter. */ | |
128 | bool avail_wrap_counter; | |
129 | ||
130 | /* Avail used flags. */ | |
131 | u16 avail_used_flags; | |
132 | ||
133 | /* Index of the next avail descriptor. */ | |
134 | u16 next_avail_idx; | |
135 | ||
136 | /* | |
137 | * Last written value to driver->flags in | |
138 | * guest byte order. | |
139 | */ | |
140 | u16 event_flags_shadow; | |
141 | ||
142 | /* Per-descriptor state. */ | |
143 | struct vring_desc_state_packed *desc_state; | |
144 | struct vring_desc_extra *desc_extra; | |
145 | ||
146 | /* DMA address and size information */ | |
147 | dma_addr_t ring_dma_addr; | |
148 | dma_addr_t driver_event_dma_addr; | |
149 | dma_addr_t device_event_dma_addr; | |
150 | size_t ring_size_in_bytes; | |
151 | size_t event_size_in_bytes; | |
152 | }; | |
153 | ||
43b4f721 | 154 | struct vring_virtqueue { |
0a8a69dd RR |
155 | struct virtqueue vq; |
156 | ||
1ce9e605 TB |
157 | /* Is this a packed ring? */ |
158 | bool packed_ring; | |
159 | ||
fb3fba6b TB |
160 | /* Is DMA API used? */ |
161 | bool use_dma_api; | |
162 | ||
7b21e34f RR |
163 | /* Can we use weak barriers? */ |
164 | bool weak_barriers; | |
165 | ||
0a8a69dd RR |
166 | /* Other side has made a mess, don't try any more. */ |
167 | bool broken; | |
168 | ||
9fa29b9d MM |
169 | /* Host supports indirect buffers */ |
170 | bool indirect; | |
171 | ||
a5c262c5 MT |
172 | /* Host publishes avail event idx */ |
173 | bool event; | |
174 | ||
8daafe9e XZ |
175 | /* Do DMA mapping by driver */ |
176 | bool premapped; | |
177 | ||
b319940f XZ |
178 | /* Do unmap or not for desc. Just when premapped is False and |
179 | * use_dma_api is true, this is true. | |
180 | */ | |
181 | bool do_unmap; | |
182 | ||
0a8a69dd RR |
183 | /* Head of free buffer list. */ |
184 | unsigned int free_head; | |
185 | /* Number we've added since last sync. */ | |
186 | unsigned int num_added; | |
187 | ||
a7722890 | 188 | /* Last used index we've seen. |
189 | * for split ring, it just contains last used index | |
190 | * for packed ring: | |
191 | * bits up to VRING_PACKED_EVENT_F_WRAP_CTR include the last used index. | |
192 | * bits from VRING_PACKED_EVENT_F_WRAP_CTR include the used wrap counter. | |
193 | */ | |
1bc4953e | 194 | u16 last_used_idx; |
0a8a69dd | 195 | |
8d622d21 MT |
196 | /* Hint for event idx: already triggered no need to disable. */ |
197 | bool event_triggered; | |
198 | ||
1ce9e605 TB |
199 | union { |
200 | /* Available for split ring */ | |
d76136e4 | 201 | struct vring_virtqueue_split split; |
e593bf97 | 202 | |
1ce9e605 | 203 | /* Available for packed ring */ |
d76136e4 | 204 | struct vring_virtqueue_packed packed; |
1ce9e605 | 205 | }; |
f277ec42 | 206 | |
0a8a69dd | 207 | /* How to notify other side. FIXME: commonalize hcalls! */ |
46f9c2b9 | 208 | bool (*notify)(struct virtqueue *vq); |
0a8a69dd | 209 | |
2a2d1382 AL |
210 | /* DMA, allocation, and size information */ |
211 | bool we_own_ring; | |
2a2d1382 | 212 | |
2713ea3c JW |
213 | /* Device used for doing DMA */ |
214 | struct device *dma_dev; | |
215 | ||
0a8a69dd RR |
216 | #ifdef DEBUG |
217 | /* They're supposed to lock for us. */ | |
218 | unsigned int in_use; | |
e93300b1 RR |
219 | |
220 | /* Figure out if their kicks are too delayed. */ | |
221 | bool last_add_time_valid; | |
222 | ktime_t last_add_time; | |
0a8a69dd | 223 | #endif |
0a8a69dd RR |
224 | }; |
225 | ||
07d9629d | 226 | static struct virtqueue *__vring_new_virtqueue(unsigned int index, |
cd4c812a | 227 | struct vring_virtqueue_split *vring_split, |
07d9629d XZ |
228 | struct virtio_device *vdev, |
229 | bool weak_barriers, | |
230 | bool context, | |
231 | bool (*notify)(struct virtqueue *), | |
232 | void (*callback)(struct virtqueue *), | |
2713ea3c JW |
233 | const char *name, |
234 | struct device *dma_dev); | |
a2b36c8d | 235 | static struct vring_desc_extra *vring_alloc_desc_extra(unsigned int num); |
6fea20e5 | 236 | static void vring_free(struct virtqueue *_vq); |
e6f633e5 TB |
237 | |
238 | /* | |
239 | * Helpers. | |
240 | */ | |
241 | ||
4b6ec919 | 242 | #define to_vvq(_vq) container_of_const(_vq, struct vring_virtqueue, vq) |
0a8a69dd | 243 | |
4b6ec919 | 244 | static bool virtqueue_use_indirect(const struct vring_virtqueue *vq, |
1adbd6b2 | 245 | unsigned int total_sg) |
2f18c2d1 | 246 | { |
2f18c2d1 TB |
247 | /* |
248 | * If the host supports indirect descriptor tables, and we have multiple | |
249 | * buffers, then go indirect. FIXME: tune this threshold | |
250 | */ | |
251 | return (vq->indirect && total_sg > 1 && vq->vq.num_free); | |
252 | } | |
253 | ||
d26c96c8 | 254 | /* |
1a937693 MT |
255 | * Modern virtio devices have feature bits to specify whether they need a |
256 | * quirk and bypass the IOMMU. If not there, just use the DMA API. | |
257 | * | |
258 | * If there, the interaction between virtio and DMA API is messy. | |
d26c96c8 AL |
259 | * |
260 | * On most systems with virtio, physical addresses match bus addresses, | |
261 | * and it doesn't particularly matter whether we use the DMA API. | |
262 | * | |
263 | * On some systems, including Xen and any system with a physical device | |
264 | * that speaks virtio behind a physical IOMMU, we must use the DMA API | |
265 | * for virtio DMA to work at all. | |
266 | * | |
267 | * On other systems, including SPARC and PPC64, virtio-pci devices are | |
268 | * enumerated as though they are behind an IOMMU, but the virtio host | |
269 | * ignores the IOMMU, so we must either pretend that the IOMMU isn't | |
270 | * there or somehow map everything as the identity. | |
271 | * | |
272 | * For the time being, we preserve historic behavior and bypass the DMA | |
273 | * API. | |
1a937693 MT |
274 | * |
275 | * TODO: install a per-device DMA ops structure that does the right thing | |
276 | * taking into account all the above quirks, and use the DMA API | |
277 | * unconditionally on data path. | |
d26c96c8 AL |
278 | */ |
279 | ||
4b6ec919 | 280 | static bool vring_use_dma_api(const struct virtio_device *vdev) |
d26c96c8 | 281 | { |
24b6842a | 282 | if (!virtio_has_dma_quirk(vdev)) |
1a937693 MT |
283 | return true; |
284 | ||
285 | /* Otherwise, we are left to guess. */ | |
78fe3987 AL |
286 | /* |
287 | * In theory, it's possible to have a buggy QEMU-supposed | |
288 | * emulated Q35 IOMMU and Xen enabled at the same time. On | |
289 | * such a configuration, virtio has never worked and will | |
290 | * not work without an even larger kludge. Instead, enable | |
291 | * the DMA API if we're a Xen guest, which at least allows | |
292 | * all of the sensible Xen configurations to work correctly. | |
293 | */ | |
294 | if (xen_domain()) | |
295 | return true; | |
296 | ||
d26c96c8 AL |
297 | return false; |
298 | } | |
299 | ||
4b6ec919 | 300 | size_t virtio_max_dma_size(const struct virtio_device *vdev) |
e6d6dd6c JR |
301 | { |
302 | size_t max_segment_size = SIZE_MAX; | |
303 | ||
304 | if (vring_use_dma_api(vdev)) | |
817fc978 | 305 | max_segment_size = dma_max_mapping_size(vdev->dev.parent); |
e6d6dd6c JR |
306 | |
307 | return max_segment_size; | |
308 | } | |
309 | EXPORT_SYMBOL_GPL(virtio_max_dma_size); | |
310 | ||
d79dca75 | 311 | static void *vring_alloc_queue(struct virtio_device *vdev, size_t size, |
2713ea3c JW |
312 | dma_addr_t *dma_handle, gfp_t flag, |
313 | struct device *dma_dev) | |
d79dca75 TB |
314 | { |
315 | if (vring_use_dma_api(vdev)) { | |
2713ea3c | 316 | return dma_alloc_coherent(dma_dev, size, |
d79dca75 TB |
317 | dma_handle, flag); |
318 | } else { | |
319 | void *queue = alloc_pages_exact(PAGE_ALIGN(size), flag); | |
320 | ||
321 | if (queue) { | |
322 | phys_addr_t phys_addr = virt_to_phys(queue); | |
323 | *dma_handle = (dma_addr_t)phys_addr; | |
324 | ||
325 | /* | |
326 | * Sanity check: make sure we dind't truncate | |
327 | * the address. The only arches I can find that | |
328 | * have 64-bit phys_addr_t but 32-bit dma_addr_t | |
329 | * are certain non-highmem MIPS and x86 | |
330 | * configurations, but these configurations | |
331 | * should never allocate physical pages above 32 | |
332 | * bits, so this is fine. Just in case, throw a | |
333 | * warning and abort if we end up with an | |
334 | * unrepresentable address. | |
335 | */ | |
336 | if (WARN_ON_ONCE(*dma_handle != phys_addr)) { | |
337 | free_pages_exact(queue, PAGE_ALIGN(size)); | |
338 | return NULL; | |
339 | } | |
340 | } | |
341 | return queue; | |
342 | } | |
343 | } | |
344 | ||
345 | static void vring_free_queue(struct virtio_device *vdev, size_t size, | |
2713ea3c JW |
346 | void *queue, dma_addr_t dma_handle, |
347 | struct device *dma_dev) | |
d79dca75 TB |
348 | { |
349 | if (vring_use_dma_api(vdev)) | |
2713ea3c | 350 | dma_free_coherent(dma_dev, size, queue, dma_handle); |
d79dca75 TB |
351 | else |
352 | free_pages_exact(queue, PAGE_ALIGN(size)); | |
353 | } | |
354 | ||
780bc790 AL |
355 | /* |
356 | * The DMA ops on various arches are rather gnarly right now, and | |
357 | * making all of the arch DMA ops work on the vring device itself | |
2713ea3c | 358 | * is a mess. |
780bc790 | 359 | */ |
1adbd6b2 | 360 | static struct device *vring_dma_dev(const struct vring_virtqueue *vq) |
780bc790 | 361 | { |
2713ea3c | 362 | return vq->dma_dev; |
780bc790 AL |
363 | } |
364 | ||
365 | /* Map one sg entry. */ | |
0e27fa6d XZ |
366 | static int vring_map_one_sg(const struct vring_virtqueue *vq, struct scatterlist *sg, |
367 | enum dma_data_direction direction, dma_addr_t *addr) | |
780bc790 | 368 | { |
d7344a2f XZ |
369 | if (vq->premapped) { |
370 | *addr = sg_dma_address(sg); | |
371 | return 0; | |
372 | } | |
373 | ||
88938359 AP |
374 | if (!vq->use_dma_api) { |
375 | /* | |
376 | * If DMA is not used, KMSAN doesn't know that the scatterlist | |
377 | * is initialized by the hardware. Explicitly check/unpoison it | |
378 | * depending on the direction. | |
379 | */ | |
380 | kmsan_handle_dma(sg_page(sg), sg->offset, sg->length, direction); | |
0e27fa6d XZ |
381 | *addr = (dma_addr_t)sg_phys(sg); |
382 | return 0; | |
88938359 | 383 | } |
780bc790 AL |
384 | |
385 | /* | |
386 | * We can't use dma_map_sg, because we don't use scatterlists in | |
387 | * the way it expects (we don't guarantee that the scatterlist | |
388 | * will exist for the lifetime of the mapping). | |
389 | */ | |
0e27fa6d | 390 | *addr = dma_map_page(vring_dma_dev(vq), |
780bc790 AL |
391 | sg_page(sg), sg->offset, sg->length, |
392 | direction); | |
0e27fa6d XZ |
393 | |
394 | if (dma_mapping_error(vring_dma_dev(vq), *addr)) | |
395 | return -ENOMEM; | |
396 | ||
397 | return 0; | |
780bc790 AL |
398 | } |
399 | ||
400 | static dma_addr_t vring_map_single(const struct vring_virtqueue *vq, | |
401 | void *cpu_addr, size_t size, | |
402 | enum dma_data_direction direction) | |
403 | { | |
fb3fba6b | 404 | if (!vq->use_dma_api) |
780bc790 AL |
405 | return (dma_addr_t)virt_to_phys(cpu_addr); |
406 | ||
407 | return dma_map_single(vring_dma_dev(vq), | |
408 | cpu_addr, size, direction); | |
409 | } | |
410 | ||
e6f633e5 TB |
411 | static int vring_mapping_error(const struct vring_virtqueue *vq, |
412 | dma_addr_t addr) | |
413 | { | |
fb3fba6b | 414 | if (!vq->use_dma_api) |
e6f633e5 TB |
415 | return 0; |
416 | ||
417 | return dma_mapping_error(vring_dma_dev(vq), addr); | |
418 | } | |
419 | ||
3a897128 XZ |
420 | static void virtqueue_init(struct vring_virtqueue *vq, u32 num) |
421 | { | |
422 | vq->vq.num_free = num; | |
423 | ||
424 | if (vq->packed_ring) | |
425 | vq->last_used_idx = 0 | (1 << VRING_PACKED_EVENT_F_WRAP_CTR); | |
426 | else | |
427 | vq->last_used_idx = 0; | |
428 | ||
429 | vq->event_triggered = false; | |
430 | vq->num_added = 0; | |
431 | ||
432 | #ifdef DEBUG | |
433 | vq->in_use = false; | |
434 | vq->last_add_time_valid = false; | |
435 | #endif | |
436 | } | |
437 | ||
e6f633e5 TB |
438 | |
439 | /* | |
440 | * Split ring specific functions - *_split(). | |
441 | */ | |
442 | ||
72b5e895 | 443 | static void vring_unmap_one_split_indirect(const struct vring_virtqueue *vq, |
4b6ec919 | 444 | const struct vring_desc *desc) |
780bc790 AL |
445 | { |
446 | u16 flags; | |
447 | ||
b319940f | 448 | if (!vq->do_unmap) |
780bc790 AL |
449 | return; |
450 | ||
451 | flags = virtio16_to_cpu(vq->vq.vdev, desc->flags); | |
452 | ||
b4282ebc XZ |
453 | dma_unmap_page(vring_dma_dev(vq), |
454 | virtio64_to_cpu(vq->vq.vdev, desc->addr), | |
455 | virtio32_to_cpu(vq->vq.vdev, desc->len), | |
456 | (flags & VRING_DESC_F_WRITE) ? | |
457 | DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
780bc790 AL |
458 | } |
459 | ||
72b5e895 JW |
460 | static unsigned int vring_unmap_one_split(const struct vring_virtqueue *vq, |
461 | unsigned int i) | |
462 | { | |
463 | struct vring_desc_extra *extra = vq->split.desc_extra; | |
464 | u16 flags; | |
465 | ||
72b5e895 JW |
466 | flags = extra[i].flags; |
467 | ||
468 | if (flags & VRING_DESC_F_INDIRECT) { | |
b319940f XZ |
469 | if (!vq->use_dma_api) |
470 | goto out; | |
471 | ||
72b5e895 JW |
472 | dma_unmap_single(vring_dma_dev(vq), |
473 | extra[i].addr, | |
474 | extra[i].len, | |
475 | (flags & VRING_DESC_F_WRITE) ? | |
476 | DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
477 | } else { | |
b319940f XZ |
478 | if (!vq->do_unmap) |
479 | goto out; | |
480 | ||
72b5e895 JW |
481 | dma_unmap_page(vring_dma_dev(vq), |
482 | extra[i].addr, | |
483 | extra[i].len, | |
484 | (flags & VRING_DESC_F_WRITE) ? | |
485 | DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
486 | } | |
487 | ||
488 | out: | |
489 | return extra[i].next; | |
490 | } | |
491 | ||
138fd251 TB |
492 | static struct vring_desc *alloc_indirect_split(struct virtqueue *_vq, |
493 | unsigned int total_sg, | |
494 | gfp_t gfp) | |
9fa29b9d MM |
495 | { |
496 | struct vring_desc *desc; | |
b25bd251 | 497 | unsigned int i; |
9fa29b9d | 498 | |
b92b1b89 WD |
499 | /* |
500 | * We require lowmem mappings for the descriptors because | |
501 | * otherwise virt_to_phys will give us bogus addresses in the | |
502 | * virtqueue. | |
503 | */ | |
82107539 | 504 | gfp &= ~__GFP_HIGHMEM; |
b92b1b89 | 505 | |
6da2ec56 | 506 | desc = kmalloc_array(total_sg, sizeof(struct vring_desc), gfp); |
9fa29b9d | 507 | if (!desc) |
b25bd251 | 508 | return NULL; |
9fa29b9d | 509 | |
b25bd251 | 510 | for (i = 0; i < total_sg; i++) |
00e6f3d9 | 511 | desc[i].next = cpu_to_virtio16(_vq->vdev, i + 1); |
b25bd251 | 512 | return desc; |
9fa29b9d MM |
513 | } |
514 | ||
fe4c3862 JW |
515 | static inline unsigned int virtqueue_add_desc_split(struct virtqueue *vq, |
516 | struct vring_desc *desc, | |
517 | unsigned int i, | |
518 | dma_addr_t addr, | |
519 | unsigned int len, | |
72b5e895 JW |
520 | u16 flags, |
521 | bool indirect) | |
fe4c3862 | 522 | { |
72b5e895 JW |
523 | struct vring_virtqueue *vring = to_vvq(vq); |
524 | struct vring_desc_extra *extra = vring->split.desc_extra; | |
525 | u16 next; | |
526 | ||
fe4c3862 JW |
527 | desc[i].flags = cpu_to_virtio16(vq->vdev, flags); |
528 | desc[i].addr = cpu_to_virtio64(vq->vdev, addr); | |
529 | desc[i].len = cpu_to_virtio32(vq->vdev, len); | |
530 | ||
72b5e895 JW |
531 | if (!indirect) { |
532 | next = extra[i].next; | |
533 | desc[i].next = cpu_to_virtio16(vq->vdev, next); | |
534 | ||
535 | extra[i].addr = addr; | |
536 | extra[i].len = len; | |
537 | extra[i].flags = flags; | |
538 | } else | |
539 | next = virtio16_to_cpu(vq->vdev, desc[i].next); | |
540 | ||
541 | return next; | |
fe4c3862 JW |
542 | } |
543 | ||
138fd251 TB |
544 | static inline int virtqueue_add_split(struct virtqueue *_vq, |
545 | struct scatterlist *sgs[], | |
546 | unsigned int total_sg, | |
547 | unsigned int out_sgs, | |
548 | unsigned int in_sgs, | |
549 | void *data, | |
550 | void *ctx, | |
551 | gfp_t gfp) | |
0a8a69dd RR |
552 | { |
553 | struct vring_virtqueue *vq = to_vvq(_vq); | |
13816c76 | 554 | struct scatterlist *sg; |
b25bd251 | 555 | struct vring_desc *desc; |
3f649ab7 | 556 | unsigned int i, n, avail, descs_used, prev, err_idx; |
1fe9b6fe | 557 | int head; |
b25bd251 | 558 | bool indirect; |
0a8a69dd | 559 | |
9fa29b9d MM |
560 | START_USE(vq); |
561 | ||
0a8a69dd | 562 | BUG_ON(data == NULL); |
5a08b04f | 563 | BUG_ON(ctx && vq->indirect); |
9fa29b9d | 564 | |
70670444 RR |
565 | if (unlikely(vq->broken)) { |
566 | END_USE(vq); | |
567 | return -EIO; | |
568 | } | |
569 | ||
4d6a105e | 570 | LAST_ADD_TIME_UPDATE(vq); |
e93300b1 | 571 | |
b25bd251 RR |
572 | BUG_ON(total_sg == 0); |
573 | ||
574 | head = vq->free_head; | |
575 | ||
35c51e09 | 576 | if (virtqueue_use_indirect(vq, total_sg)) |
138fd251 | 577 | desc = alloc_indirect_split(_vq, total_sg, gfp); |
44ed8089 | 578 | else { |
b25bd251 | 579 | desc = NULL; |
e593bf97 | 580 | WARN_ON_ONCE(total_sg > vq->split.vring.num && !vq->indirect); |
44ed8089 | 581 | } |
b25bd251 RR |
582 | |
583 | if (desc) { | |
584 | /* Use a single buffer which doesn't continue */ | |
780bc790 | 585 | indirect = true; |
b25bd251 RR |
586 | /* Set up rest to use this indirect table. */ |
587 | i = 0; | |
588 | descs_used = 1; | |
b25bd251 | 589 | } else { |
780bc790 | 590 | indirect = false; |
e593bf97 | 591 | desc = vq->split.vring.desc; |
b25bd251 RR |
592 | i = head; |
593 | descs_used = total_sg; | |
9fa29b9d MM |
594 | } |
595 | ||
b4b4ff73 | 596 | if (unlikely(vq->vq.num_free < descs_used)) { |
0a8a69dd | 597 | pr_debug("Can't add buf len %i - avail = %i\n", |
b25bd251 | 598 | descs_used, vq->vq.num_free); |
44653eae RR |
599 | /* FIXME: for historical reasons, we force a notify here if |
600 | * there are outgoing parts to the buffer. Presumably the | |
601 | * host should service the ring ASAP. */ | |
13816c76 | 602 | if (out_sgs) |
44653eae | 603 | vq->notify(&vq->vq); |
58625edf WY |
604 | if (indirect) |
605 | kfree(desc); | |
0a8a69dd RR |
606 | END_USE(vq); |
607 | return -ENOSPC; | |
608 | } | |
609 | ||
13816c76 | 610 | for (n = 0; n < out_sgs; n++) { |
eeebf9b1 | 611 | for (sg = sgs[n]; sg; sg = sg_next(sg)) { |
0e27fa6d XZ |
612 | dma_addr_t addr; |
613 | ||
614 | if (vring_map_one_sg(vq, sg, DMA_TO_DEVICE, &addr)) | |
780bc790 AL |
615 | goto unmap_release; |
616 | ||
13816c76 | 617 | prev = i; |
72b5e895 JW |
618 | /* Note that we trust indirect descriptor |
619 | * table since it use stream DMA mapping. | |
620 | */ | |
fe4c3862 | 621 | i = virtqueue_add_desc_split(_vq, desc, i, addr, sg->length, |
72b5e895 JW |
622 | VRING_DESC_F_NEXT, |
623 | indirect); | |
13816c76 | 624 | } |
0a8a69dd | 625 | } |
13816c76 | 626 | for (; n < (out_sgs + in_sgs); n++) { |
eeebf9b1 | 627 | for (sg = sgs[n]; sg; sg = sg_next(sg)) { |
0e27fa6d XZ |
628 | dma_addr_t addr; |
629 | ||
630 | if (vring_map_one_sg(vq, sg, DMA_FROM_DEVICE, &addr)) | |
780bc790 AL |
631 | goto unmap_release; |
632 | ||
13816c76 | 633 | prev = i; |
72b5e895 JW |
634 | /* Note that we trust indirect descriptor |
635 | * table since it use stream DMA mapping. | |
636 | */ | |
fe4c3862 JW |
637 | i = virtqueue_add_desc_split(_vq, desc, i, addr, |
638 | sg->length, | |
639 | VRING_DESC_F_NEXT | | |
72b5e895 JW |
640 | VRING_DESC_F_WRITE, |
641 | indirect); | |
13816c76 | 642 | } |
0a8a69dd RR |
643 | } |
644 | /* Last one doesn't continue. */ | |
00e6f3d9 | 645 | desc[prev].flags &= cpu_to_virtio16(_vq->vdev, ~VRING_DESC_F_NEXT); |
b319940f | 646 | if (!indirect && vq->do_unmap) |
890d3356 | 647 | vq->split.desc_extra[prev & (vq->split.vring.num - 1)].flags &= |
72b5e895 | 648 | ~VRING_DESC_F_NEXT; |
0a8a69dd | 649 | |
780bc790 AL |
650 | if (indirect) { |
651 | /* Now that the indirect table is filled in, map it. */ | |
652 | dma_addr_t addr = vring_map_single( | |
653 | vq, desc, total_sg * sizeof(struct vring_desc), | |
654 | DMA_TO_DEVICE); | |
d7344a2f XZ |
655 | if (vring_mapping_error(vq, addr)) { |
656 | if (vq->premapped) | |
657 | goto free_indirect; | |
658 | ||
780bc790 | 659 | goto unmap_release; |
d7344a2f | 660 | } |
780bc790 | 661 | |
fe4c3862 JW |
662 | virtqueue_add_desc_split(_vq, vq->split.vring.desc, |
663 | head, addr, | |
664 | total_sg * sizeof(struct vring_desc), | |
72b5e895 JW |
665 | VRING_DESC_F_INDIRECT, |
666 | false); | |
780bc790 AL |
667 | } |
668 | ||
669 | /* We're using some buffers from the free list. */ | |
670 | vq->vq.num_free -= descs_used; | |
671 | ||
0a8a69dd | 672 | /* Update free pointer */ |
b25bd251 | 673 | if (indirect) |
72b5e895 | 674 | vq->free_head = vq->split.desc_extra[head].next; |
b25bd251 RR |
675 | else |
676 | vq->free_head = i; | |
0a8a69dd | 677 | |
780bc790 | 678 | /* Store token and indirect buffer state. */ |
cbeedb72 | 679 | vq->split.desc_state[head].data = data; |
780bc790 | 680 | if (indirect) |
cbeedb72 | 681 | vq->split.desc_state[head].indir_desc = desc; |
87646a34 | 682 | else |
cbeedb72 | 683 | vq->split.desc_state[head].indir_desc = ctx; |
0a8a69dd RR |
684 | |
685 | /* Put entry in available array (but don't update avail->idx until they | |
3b720b8c | 686 | * do sync). */ |
e593bf97 TB |
687 | avail = vq->split.avail_idx_shadow & (vq->split.vring.num - 1); |
688 | vq->split.vring.avail->ring[avail] = cpu_to_virtio16(_vq->vdev, head); | |
0a8a69dd | 689 | |
ee7cd898 RR |
690 | /* Descriptors and available array need to be set before we expose the |
691 | * new available array entries. */ | |
a9a0fef7 | 692 | virtio_wmb(vq->weak_barriers); |
e593bf97 TB |
693 | vq->split.avail_idx_shadow++; |
694 | vq->split.vring.avail->idx = cpu_to_virtio16(_vq->vdev, | |
695 | vq->split.avail_idx_shadow); | |
ee7cd898 RR |
696 | vq->num_added++; |
697 | ||
5e05bf58 TH |
698 | pr_debug("Added buffer head %i to %p\n", head, vq); |
699 | END_USE(vq); | |
700 | ||
ee7cd898 RR |
701 | /* This is very unlikely, but theoretically possible. Kick |
702 | * just in case. */ | |
703 | if (unlikely(vq->num_added == (1 << 16) - 1)) | |
704 | virtqueue_kick(_vq); | |
705 | ||
98e8c6bc | 706 | return 0; |
780bc790 AL |
707 | |
708 | unmap_release: | |
709 | err_idx = i; | |
cf8f1696 ML |
710 | |
711 | if (indirect) | |
712 | i = 0; | |
713 | else | |
714 | i = head; | |
780bc790 AL |
715 | |
716 | for (n = 0; n < total_sg; n++) { | |
717 | if (i == err_idx) | |
718 | break; | |
72b5e895 JW |
719 | if (indirect) { |
720 | vring_unmap_one_split_indirect(vq, &desc[i]); | |
721 | i = virtio16_to_cpu(_vq->vdev, desc[i].next); | |
722 | } else | |
723 | i = vring_unmap_one_split(vq, i); | |
780bc790 AL |
724 | } |
725 | ||
d7344a2f | 726 | free_indirect: |
780bc790 AL |
727 | if (indirect) |
728 | kfree(desc); | |
729 | ||
3cc36f6e | 730 | END_USE(vq); |
f7728002 | 731 | return -ENOMEM; |
0a8a69dd | 732 | } |
13816c76 | 733 | |
138fd251 | 734 | static bool virtqueue_kick_prepare_split(struct virtqueue *_vq) |
0a8a69dd RR |
735 | { |
736 | struct vring_virtqueue *vq = to_vvq(_vq); | |
a5c262c5 | 737 | u16 new, old; |
41f0377f RR |
738 | bool needs_kick; |
739 | ||
0a8a69dd | 740 | START_USE(vq); |
a72caae2 JW |
741 | /* We need to expose available array entries before checking avail |
742 | * event. */ | |
a9a0fef7 | 743 | virtio_mb(vq->weak_barriers); |
0a8a69dd | 744 | |
e593bf97 TB |
745 | old = vq->split.avail_idx_shadow - vq->num_added; |
746 | new = vq->split.avail_idx_shadow; | |
0a8a69dd RR |
747 | vq->num_added = 0; |
748 | ||
4d6a105e TB |
749 | LAST_ADD_TIME_CHECK(vq); |
750 | LAST_ADD_TIME_INVALID(vq); | |
e93300b1 | 751 | |
41f0377f | 752 | if (vq->event) { |
e593bf97 TB |
753 | needs_kick = vring_need_event(virtio16_to_cpu(_vq->vdev, |
754 | vring_avail_event(&vq->split.vring)), | |
41f0377f RR |
755 | new, old); |
756 | } else { | |
e593bf97 TB |
757 | needs_kick = !(vq->split.vring.used->flags & |
758 | cpu_to_virtio16(_vq->vdev, | |
759 | VRING_USED_F_NO_NOTIFY)); | |
41f0377f | 760 | } |
0a8a69dd | 761 | END_USE(vq); |
41f0377f RR |
762 | return needs_kick; |
763 | } | |
138fd251 | 764 | |
138fd251 TB |
765 | static void detach_buf_split(struct vring_virtqueue *vq, unsigned int head, |
766 | void **ctx) | |
0a8a69dd | 767 | { |
780bc790 | 768 | unsigned int i, j; |
c60923cb | 769 | __virtio16 nextflag = cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_NEXT); |
0a8a69dd RR |
770 | |
771 | /* Clear data ptr. */ | |
cbeedb72 | 772 | vq->split.desc_state[head].data = NULL; |
0a8a69dd | 773 | |
780bc790 | 774 | /* Put back on free list: unmap first-level descriptors and find end */ |
0a8a69dd | 775 | i = head; |
9fa29b9d | 776 | |
e593bf97 | 777 | while (vq->split.vring.desc[i].flags & nextflag) { |
72b5e895 JW |
778 | vring_unmap_one_split(vq, i); |
779 | i = vq->split.desc_extra[i].next; | |
06ca287d | 780 | vq->vq.num_free++; |
0a8a69dd RR |
781 | } |
782 | ||
72b5e895 JW |
783 | vring_unmap_one_split(vq, i); |
784 | vq->split.desc_extra[i].next = vq->free_head; | |
0a8a69dd | 785 | vq->free_head = head; |
780bc790 | 786 | |
0a8a69dd | 787 | /* Plus final descriptor */ |
06ca287d | 788 | vq->vq.num_free++; |
780bc790 | 789 | |
5a08b04f | 790 | if (vq->indirect) { |
cbeedb72 TB |
791 | struct vring_desc *indir_desc = |
792 | vq->split.desc_state[head].indir_desc; | |
5a08b04f MT |
793 | u32 len; |
794 | ||
795 | /* Free the indirect table, if any, now that it's unmapped. */ | |
796 | if (!indir_desc) | |
797 | return; | |
798 | ||
72b5e895 | 799 | len = vq->split.desc_extra[head].len; |
780bc790 | 800 | |
72b5e895 JW |
801 | BUG_ON(!(vq->split.desc_extra[head].flags & |
802 | VRING_DESC_F_INDIRECT)); | |
780bc790 AL |
803 | BUG_ON(len == 0 || len % sizeof(struct vring_desc)); |
804 | ||
b319940f | 805 | if (vq->do_unmap) { |
610c708b XZ |
806 | for (j = 0; j < len / sizeof(struct vring_desc); j++) |
807 | vring_unmap_one_split_indirect(vq, &indir_desc[j]); | |
808 | } | |
780bc790 | 809 | |
5a08b04f | 810 | kfree(indir_desc); |
cbeedb72 | 811 | vq->split.desc_state[head].indir_desc = NULL; |
5a08b04f | 812 | } else if (ctx) { |
cbeedb72 | 813 | *ctx = vq->split.desc_state[head].indir_desc; |
780bc790 | 814 | } |
0a8a69dd RR |
815 | } |
816 | ||
1adbd6b2 | 817 | static bool more_used_split(const struct vring_virtqueue *vq) |
0a8a69dd | 818 | { |
e593bf97 TB |
819 | return vq->last_used_idx != virtio16_to_cpu(vq->vq.vdev, |
820 | vq->split.vring.used->idx); | |
0a8a69dd RR |
821 | } |
822 | ||
138fd251 TB |
823 | static void *virtqueue_get_buf_ctx_split(struct virtqueue *_vq, |
824 | unsigned int *len, | |
825 | void **ctx) | |
0a8a69dd RR |
826 | { |
827 | struct vring_virtqueue *vq = to_vvq(_vq); | |
828 | void *ret; | |
829 | unsigned int i; | |
3b720b8c | 830 | u16 last_used; |
0a8a69dd RR |
831 | |
832 | START_USE(vq); | |
833 | ||
5ef82752 RR |
834 | if (unlikely(vq->broken)) { |
835 | END_USE(vq); | |
836 | return NULL; | |
837 | } | |
838 | ||
138fd251 | 839 | if (!more_used_split(vq)) { |
0a8a69dd RR |
840 | pr_debug("No more buffers in queue\n"); |
841 | END_USE(vq); | |
842 | return NULL; | |
843 | } | |
844 | ||
2d61ba95 | 845 | /* Only get used array entries after they have been exposed by host. */ |
a9a0fef7 | 846 | virtio_rmb(vq->weak_barriers); |
2d61ba95 | 847 | |
e593bf97 TB |
848 | last_used = (vq->last_used_idx & (vq->split.vring.num - 1)); |
849 | i = virtio32_to_cpu(_vq->vdev, | |
850 | vq->split.vring.used->ring[last_used].id); | |
851 | *len = virtio32_to_cpu(_vq->vdev, | |
852 | vq->split.vring.used->ring[last_used].len); | |
0a8a69dd | 853 | |
e593bf97 | 854 | if (unlikely(i >= vq->split.vring.num)) { |
0a8a69dd RR |
855 | BAD_RING(vq, "id %u out of range\n", i); |
856 | return NULL; | |
857 | } | |
cbeedb72 | 858 | if (unlikely(!vq->split.desc_state[i].data)) { |
0a8a69dd RR |
859 | BAD_RING(vq, "id %u is not a head!\n", i); |
860 | return NULL; | |
861 | } | |
862 | ||
138fd251 | 863 | /* detach_buf_split clears data, so grab it now. */ |
cbeedb72 | 864 | ret = vq->split.desc_state[i].data; |
138fd251 | 865 | detach_buf_split(vq, i, ctx); |
0a8a69dd | 866 | vq->last_used_idx++; |
a5c262c5 MT |
867 | /* If we expect an interrupt for the next entry, tell host |
868 | * by writing event index and flush out the write before | |
869 | * the read in the next get_buf call. */ | |
e593bf97 | 870 | if (!(vq->split.avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) |
788e5b3a | 871 | virtio_store_mb(vq->weak_barriers, |
e593bf97 | 872 | &vring_used_event(&vq->split.vring), |
788e5b3a | 873 | cpu_to_virtio16(_vq->vdev, vq->last_used_idx)); |
a5c262c5 | 874 | |
4d6a105e | 875 | LAST_ADD_TIME_INVALID(vq); |
e93300b1 | 876 | |
0a8a69dd RR |
877 | END_USE(vq); |
878 | return ret; | |
879 | } | |
138fd251 | 880 | |
138fd251 | 881 | static void virtqueue_disable_cb_split(struct virtqueue *_vq) |
18445c4d RR |
882 | { |
883 | struct vring_virtqueue *vq = to_vvq(_vq); | |
884 | ||
e593bf97 TB |
885 | if (!(vq->split.avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) { |
886 | vq->split.avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT; | |
6c0b057c AH |
887 | |
888 | /* | |
889 | * If device triggered an event already it won't trigger one again: | |
890 | * no need to disable. | |
891 | */ | |
892 | if (vq->event_triggered) | |
893 | return; | |
894 | ||
8d622d21 MT |
895 | if (vq->event) |
896 | /* TODO: this is a hack. Figure out a cleaner value to write. */ | |
897 | vring_used_event(&vq->split.vring) = 0x0; | |
898 | else | |
e593bf97 TB |
899 | vq->split.vring.avail->flags = |
900 | cpu_to_virtio16(_vq->vdev, | |
901 | vq->split.avail_flags_shadow); | |
f277ec42 | 902 | } |
18445c4d RR |
903 | } |
904 | ||
31532340 | 905 | static unsigned int virtqueue_enable_cb_prepare_split(struct virtqueue *_vq) |
0a8a69dd RR |
906 | { |
907 | struct vring_virtqueue *vq = to_vvq(_vq); | |
cc229884 | 908 | u16 last_used_idx; |
0a8a69dd RR |
909 | |
910 | START_USE(vq); | |
0a8a69dd RR |
911 | |
912 | /* We optimistically turn back on interrupts, then check if there was | |
913 | * more to do. */ | |
a5c262c5 MT |
914 | /* Depending on the VIRTIO_RING_F_EVENT_IDX feature, we need to |
915 | * either clear the flags bit or point the event index at the next | |
916 | * entry. Always do both to keep code simple. */ | |
e593bf97 TB |
917 | if (vq->split.avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT) { |
918 | vq->split.avail_flags_shadow &= ~VRING_AVAIL_F_NO_INTERRUPT; | |
0ea1e4a6 | 919 | if (!vq->event) |
e593bf97 TB |
920 | vq->split.vring.avail->flags = |
921 | cpu_to_virtio16(_vq->vdev, | |
922 | vq->split.avail_flags_shadow); | |
f277ec42 | 923 | } |
e593bf97 TB |
924 | vring_used_event(&vq->split.vring) = cpu_to_virtio16(_vq->vdev, |
925 | last_used_idx = vq->last_used_idx); | |
cc229884 MT |
926 | END_USE(vq); |
927 | return last_used_idx; | |
928 | } | |
138fd251 | 929 | |
31532340 | 930 | static bool virtqueue_poll_split(struct virtqueue *_vq, unsigned int last_used_idx) |
138fd251 TB |
931 | { |
932 | struct vring_virtqueue *vq = to_vvq(_vq); | |
933 | ||
934 | return (u16)last_used_idx != virtio16_to_cpu(_vq->vdev, | |
e593bf97 | 935 | vq->split.vring.used->idx); |
138fd251 TB |
936 | } |
937 | ||
138fd251 | 938 | static bool virtqueue_enable_cb_delayed_split(struct virtqueue *_vq) |
7ab358c2 MT |
939 | { |
940 | struct vring_virtqueue *vq = to_vvq(_vq); | |
941 | u16 bufs; | |
942 | ||
943 | START_USE(vq); | |
944 | ||
945 | /* We optimistically turn back on interrupts, then check if there was | |
946 | * more to do. */ | |
947 | /* Depending on the VIRTIO_RING_F_USED_EVENT_IDX feature, we need to | |
948 | * either clear the flags bit or point the event index at the next | |
0ea1e4a6 | 949 | * entry. Always update the event index to keep code simple. */ |
e593bf97 TB |
950 | if (vq->split.avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT) { |
951 | vq->split.avail_flags_shadow &= ~VRING_AVAIL_F_NO_INTERRUPT; | |
0ea1e4a6 | 952 | if (!vq->event) |
e593bf97 TB |
953 | vq->split.vring.avail->flags = |
954 | cpu_to_virtio16(_vq->vdev, | |
955 | vq->split.avail_flags_shadow); | |
f277ec42 | 956 | } |
7ab358c2 | 957 | /* TODO: tune this threshold */ |
e593bf97 | 958 | bufs = (u16)(vq->split.avail_idx_shadow - vq->last_used_idx) * 3 / 4; |
788e5b3a MT |
959 | |
960 | virtio_store_mb(vq->weak_barriers, | |
e593bf97 | 961 | &vring_used_event(&vq->split.vring), |
788e5b3a MT |
962 | cpu_to_virtio16(_vq->vdev, vq->last_used_idx + bufs)); |
963 | ||
e593bf97 TB |
964 | if (unlikely((u16)(virtio16_to_cpu(_vq->vdev, vq->split.vring.used->idx) |
965 | - vq->last_used_idx) > bufs)) { | |
7ab358c2 MT |
966 | END_USE(vq); |
967 | return false; | |
968 | } | |
969 | ||
970 | END_USE(vq); | |
971 | return true; | |
972 | } | |
7ab358c2 | 973 | |
138fd251 | 974 | static void *virtqueue_detach_unused_buf_split(struct virtqueue *_vq) |
c021eac4 SM |
975 | { |
976 | struct vring_virtqueue *vq = to_vvq(_vq); | |
977 | unsigned int i; | |
978 | void *buf; | |
979 | ||
980 | START_USE(vq); | |
981 | ||
e593bf97 | 982 | for (i = 0; i < vq->split.vring.num; i++) { |
cbeedb72 | 983 | if (!vq->split.desc_state[i].data) |
c021eac4 | 984 | continue; |
138fd251 | 985 | /* detach_buf_split clears data, so grab it now. */ |
cbeedb72 | 986 | buf = vq->split.desc_state[i].data; |
138fd251 | 987 | detach_buf_split(vq, i, NULL); |
e593bf97 TB |
988 | vq->split.avail_idx_shadow--; |
989 | vq->split.vring.avail->idx = cpu_to_virtio16(_vq->vdev, | |
990 | vq->split.avail_idx_shadow); | |
c021eac4 SM |
991 | END_USE(vq); |
992 | return buf; | |
993 | } | |
994 | /* That should have freed everything. */ | |
e593bf97 | 995 | BUG_ON(vq->vq.num_free != vq->split.vring.num); |
c021eac4 SM |
996 | |
997 | END_USE(vq); | |
998 | return NULL; | |
999 | } | |
138fd251 | 1000 | |
198fa7be XZ |
1001 | static void virtqueue_vring_init_split(struct vring_virtqueue_split *vring_split, |
1002 | struct vring_virtqueue *vq) | |
1003 | { | |
1004 | struct virtio_device *vdev; | |
1005 | ||
1006 | vdev = vq->vq.vdev; | |
1007 | ||
1008 | vring_split->avail_flags_shadow = 0; | |
1009 | vring_split->avail_idx_shadow = 0; | |
1010 | ||
1011 | /* No callback? Tell other side not to bother us. */ | |
1012 | if (!vq->vq.callback) { | |
1013 | vring_split->avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT; | |
1014 | if (!vq->event) | |
1015 | vring_split->vring.avail->flags = cpu_to_virtio16(vdev, | |
1016 | vring_split->avail_flags_shadow); | |
1017 | } | |
1018 | } | |
1019 | ||
e5175b41 XZ |
1020 | static void virtqueue_reinit_split(struct vring_virtqueue *vq) |
1021 | { | |
1022 | int num; | |
1023 | ||
1024 | num = vq->split.vring.num; | |
1025 | ||
1026 | vq->split.vring.avail->flags = 0; | |
1027 | vq->split.vring.avail->idx = 0; | |
1028 | ||
1029 | /* reset avail event */ | |
1030 | vq->split.vring.avail->ring[num] = 0; | |
1031 | ||
1032 | vq->split.vring.used->flags = 0; | |
1033 | vq->split.vring.used->idx = 0; | |
1034 | ||
1035 | /* reset used event */ | |
1036 | *(__virtio16 *)&(vq->split.vring.used->ring[num]) = 0; | |
1037 | ||
1038 | virtqueue_init(vq, num); | |
1039 | ||
1040 | virtqueue_vring_init_split(&vq->split, vq); | |
1041 | } | |
1042 | ||
e1d6a423 XZ |
1043 | static void virtqueue_vring_attach_split(struct vring_virtqueue *vq, |
1044 | struct vring_virtqueue_split *vring_split) | |
1045 | { | |
1046 | vq->split = *vring_split; | |
1047 | ||
1048 | /* Put everything in free lists. */ | |
1049 | vq->free_head = 0; | |
1050 | } | |
1051 | ||
a2b36c8d XZ |
1052 | static int vring_alloc_state_extra_split(struct vring_virtqueue_split *vring_split) |
1053 | { | |
1054 | struct vring_desc_state_split *state; | |
1055 | struct vring_desc_extra *extra; | |
1056 | u32 num = vring_split->vring.num; | |
1057 | ||
1058 | state = kmalloc_array(num, sizeof(struct vring_desc_state_split), GFP_KERNEL); | |
1059 | if (!state) | |
1060 | goto err_state; | |
1061 | ||
1062 | extra = vring_alloc_desc_extra(num); | |
1063 | if (!extra) | |
1064 | goto err_extra; | |
1065 | ||
1066 | memset(state, 0, num * sizeof(struct vring_desc_state_split)); | |
1067 | ||
1068 | vring_split->desc_state = state; | |
1069 | vring_split->desc_extra = extra; | |
1070 | return 0; | |
1071 | ||
1072 | err_extra: | |
1073 | kfree(state); | |
1074 | err_state: | |
1075 | return -ENOMEM; | |
1076 | } | |
1077 | ||
89f05d94 | 1078 | static void vring_free_split(struct vring_virtqueue_split *vring_split, |
2713ea3c | 1079 | struct virtio_device *vdev, struct device *dma_dev) |
89f05d94 XZ |
1080 | { |
1081 | vring_free_queue(vdev, vring_split->queue_size_in_bytes, | |
1082 | vring_split->vring.desc, | |
2713ea3c JW |
1083 | vring_split->queue_dma_addr, |
1084 | dma_dev); | |
89f05d94 XZ |
1085 | |
1086 | kfree(vring_split->desc_state); | |
1087 | kfree(vring_split->desc_extra); | |
1088 | } | |
1089 | ||
c2d87fe6 XZ |
1090 | static int vring_alloc_queue_split(struct vring_virtqueue_split *vring_split, |
1091 | struct virtio_device *vdev, | |
1092 | u32 num, | |
1093 | unsigned int vring_align, | |
2713ea3c JW |
1094 | bool may_reduce_num, |
1095 | struct device *dma_dev) | |
d79dca75 | 1096 | { |
d79dca75 TB |
1097 | void *queue = NULL; |
1098 | dma_addr_t dma_addr; | |
d79dca75 TB |
1099 | |
1100 | /* We assume num is a power of 2. */ | |
b9d978a8 | 1101 | if (!is_power_of_2(num)) { |
d79dca75 | 1102 | dev_warn(&vdev->dev, "Bad virtqueue length %u\n", num); |
c2d87fe6 | 1103 | return -EINVAL; |
d79dca75 TB |
1104 | } |
1105 | ||
1106 | /* TODO: allocate each queue chunk individually */ | |
1107 | for (; num && vring_size(num, vring_align) > PAGE_SIZE; num /= 2) { | |
1108 | queue = vring_alloc_queue(vdev, vring_size(num, vring_align), | |
1109 | &dma_addr, | |
2713ea3c JW |
1110 | GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO, |
1111 | dma_dev); | |
d79dca75 TB |
1112 | if (queue) |
1113 | break; | |
cf94db21 | 1114 | if (!may_reduce_num) |
c2d87fe6 | 1115 | return -ENOMEM; |
d79dca75 TB |
1116 | } |
1117 | ||
1118 | if (!num) | |
c2d87fe6 | 1119 | return -ENOMEM; |
d79dca75 TB |
1120 | |
1121 | if (!queue) { | |
1122 | /* Try to get a single page. You are my only hope! */ | |
1123 | queue = vring_alloc_queue(vdev, vring_size(num, vring_align), | |
2713ea3c JW |
1124 | &dma_addr, GFP_KERNEL | __GFP_ZERO, |
1125 | dma_dev); | |
d79dca75 TB |
1126 | } |
1127 | if (!queue) | |
c2d87fe6 XZ |
1128 | return -ENOMEM; |
1129 | ||
1130 | vring_init(&vring_split->vring, num, queue, vring_align); | |
1131 | ||
1132 | vring_split->queue_dma_addr = dma_addr; | |
1133 | vring_split->queue_size_in_bytes = vring_size(num, vring_align); | |
d79dca75 | 1134 | |
af36b16f XZ |
1135 | vring_split->vring_align = vring_align; |
1136 | vring_split->may_reduce_num = may_reduce_num; | |
1137 | ||
c2d87fe6 XZ |
1138 | return 0; |
1139 | } | |
1140 | ||
1141 | static struct virtqueue *vring_create_virtqueue_split( | |
1142 | unsigned int index, | |
1143 | unsigned int num, | |
1144 | unsigned int vring_align, | |
1145 | struct virtio_device *vdev, | |
1146 | bool weak_barriers, | |
1147 | bool may_reduce_num, | |
1148 | bool context, | |
1149 | bool (*notify)(struct virtqueue *), | |
1150 | void (*callback)(struct virtqueue *), | |
2713ea3c JW |
1151 | const char *name, |
1152 | struct device *dma_dev) | |
c2d87fe6 XZ |
1153 | { |
1154 | struct vring_virtqueue_split vring_split = {}; | |
1155 | struct virtqueue *vq; | |
1156 | int err; | |
1157 | ||
1158 | err = vring_alloc_queue_split(&vring_split, vdev, num, vring_align, | |
2713ea3c | 1159 | may_reduce_num, dma_dev); |
c2d87fe6 XZ |
1160 | if (err) |
1161 | return NULL; | |
d79dca75 | 1162 | |
cd4c812a | 1163 | vq = __vring_new_virtqueue(index, &vring_split, vdev, weak_barriers, |
2713ea3c | 1164 | context, notify, callback, name, dma_dev); |
d79dca75 | 1165 | if (!vq) { |
2713ea3c | 1166 | vring_free_split(&vring_split, vdev, dma_dev); |
d79dca75 TB |
1167 | return NULL; |
1168 | } | |
1169 | ||
d79dca75 TB |
1170 | to_vvq(vq)->we_own_ring = true; |
1171 | ||
1172 | return vq; | |
1173 | } | |
1174 | ||
6fea20e5 XZ |
1175 | static int virtqueue_resize_split(struct virtqueue *_vq, u32 num) |
1176 | { | |
1177 | struct vring_virtqueue_split vring_split = {}; | |
1178 | struct vring_virtqueue *vq = to_vvq(_vq); | |
1179 | struct virtio_device *vdev = _vq->vdev; | |
1180 | int err; | |
1181 | ||
1182 | err = vring_alloc_queue_split(&vring_split, vdev, num, | |
1183 | vq->split.vring_align, | |
2713ea3c JW |
1184 | vq->split.may_reduce_num, |
1185 | vring_dma_dev(vq)); | |
6fea20e5 XZ |
1186 | if (err) |
1187 | goto err; | |
1188 | ||
1189 | err = vring_alloc_state_extra_split(&vring_split); | |
1190 | if (err) | |
1191 | goto err_state_extra; | |
1192 | ||
1193 | vring_free(&vq->vq); | |
1194 | ||
1195 | virtqueue_vring_init_split(&vring_split, vq); | |
1196 | ||
1197 | virtqueue_init(vq, vring_split.vring.num); | |
1198 | virtqueue_vring_attach_split(vq, &vring_split); | |
1199 | ||
1200 | return 0; | |
1201 | ||
1202 | err_state_extra: | |
2713ea3c | 1203 | vring_free_split(&vring_split, vdev, vring_dma_dev(vq)); |
6fea20e5 XZ |
1204 | err: |
1205 | virtqueue_reinit_split(vq); | |
1206 | return -ENOMEM; | |
1207 | } | |
1208 | ||
e6f633e5 | 1209 | |
1ce9e605 TB |
1210 | /* |
1211 | * Packed ring specific functions - *_packed(). | |
1212 | */ | |
1adbd6b2 | 1213 | static bool packed_used_wrap_counter(u16 last_used_idx) |
a7722890 | 1214 | { |
1215 | return !!(last_used_idx & (1 << VRING_PACKED_EVENT_F_WRAP_CTR)); | |
1216 | } | |
1217 | ||
1adbd6b2 | 1218 | static u16 packed_last_used(u16 last_used_idx) |
a7722890 | 1219 | { |
1220 | return last_used_idx & ~(-(1 << VRING_PACKED_EVENT_F_WRAP_CTR)); | |
1221 | } | |
1ce9e605 | 1222 | |
d80dc15b | 1223 | static void vring_unmap_extra_packed(const struct vring_virtqueue *vq, |
4b6ec919 | 1224 | const struct vring_desc_extra *extra) |
1ce9e605 TB |
1225 | { |
1226 | u16 flags; | |
1227 | ||
d80dc15b | 1228 | flags = extra->flags; |
1ce9e605 TB |
1229 | |
1230 | if (flags & VRING_DESC_F_INDIRECT) { | |
b319940f XZ |
1231 | if (!vq->use_dma_api) |
1232 | return; | |
1233 | ||
1ce9e605 | 1234 | dma_unmap_single(vring_dma_dev(vq), |
d80dc15b | 1235 | extra->addr, extra->len, |
1ce9e605 TB |
1236 | (flags & VRING_DESC_F_WRITE) ? |
1237 | DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
1238 | } else { | |
b319940f XZ |
1239 | if (!vq->do_unmap) |
1240 | return; | |
1241 | ||
1ce9e605 | 1242 | dma_unmap_page(vring_dma_dev(vq), |
d80dc15b | 1243 | extra->addr, extra->len, |
1ce9e605 TB |
1244 | (flags & VRING_DESC_F_WRITE) ? |
1245 | DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
1246 | } | |
1247 | } | |
1248 | ||
1249 | static void vring_unmap_desc_packed(const struct vring_virtqueue *vq, | |
4b6ec919 | 1250 | const struct vring_packed_desc *desc) |
1ce9e605 TB |
1251 | { |
1252 | u16 flags; | |
1253 | ||
b319940f | 1254 | if (!vq->do_unmap) |
1ce9e605 TB |
1255 | return; |
1256 | ||
1257 | flags = le16_to_cpu(desc->flags); | |
1258 | ||
920379a4 XZ |
1259 | dma_unmap_page(vring_dma_dev(vq), |
1260 | le64_to_cpu(desc->addr), | |
1261 | le32_to_cpu(desc->len), | |
1262 | (flags & VRING_DESC_F_WRITE) ? | |
1263 | DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
1ce9e605 TB |
1264 | } |
1265 | ||
1266 | static struct vring_packed_desc *alloc_indirect_packed(unsigned int total_sg, | |
1267 | gfp_t gfp) | |
1268 | { | |
1269 | struct vring_packed_desc *desc; | |
1270 | ||
1271 | /* | |
1272 | * We require lowmem mappings for the descriptors because | |
1273 | * otherwise virt_to_phys will give us bogus addresses in the | |
1274 | * virtqueue. | |
1275 | */ | |
1276 | gfp &= ~__GFP_HIGHMEM; | |
1277 | ||
1278 | desc = kmalloc_array(total_sg, sizeof(struct vring_packed_desc), gfp); | |
1279 | ||
1280 | return desc; | |
1281 | } | |
1282 | ||
1283 | static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq, | |
8d7670f3 XZ |
1284 | struct scatterlist *sgs[], |
1285 | unsigned int total_sg, | |
1286 | unsigned int out_sgs, | |
1287 | unsigned int in_sgs, | |
1288 | void *data, | |
1289 | gfp_t gfp) | |
1ce9e605 TB |
1290 | { |
1291 | struct vring_packed_desc *desc; | |
1292 | struct scatterlist *sg; | |
1293 | unsigned int i, n, err_idx; | |
1294 | u16 head, id; | |
1295 | dma_addr_t addr; | |
1296 | ||
1297 | head = vq->packed.next_avail_idx; | |
1298 | desc = alloc_indirect_packed(total_sg, gfp); | |
fc6d70f4 XZ |
1299 | if (!desc) |
1300 | return -ENOMEM; | |
1ce9e605 TB |
1301 | |
1302 | if (unlikely(vq->vq.num_free < 1)) { | |
1303 | pr_debug("Can't add buf len 1 - avail = 0\n"); | |
df0bfe75 | 1304 | kfree(desc); |
1ce9e605 TB |
1305 | END_USE(vq); |
1306 | return -ENOSPC; | |
1307 | } | |
1308 | ||
1309 | i = 0; | |
1310 | id = vq->free_head; | |
1311 | BUG_ON(id == vq->packed.vring.num); | |
1312 | ||
1313 | for (n = 0; n < out_sgs + in_sgs; n++) { | |
1314 | for (sg = sgs[n]; sg; sg = sg_next(sg)) { | |
0e27fa6d XZ |
1315 | if (vring_map_one_sg(vq, sg, n < out_sgs ? |
1316 | DMA_TO_DEVICE : DMA_FROM_DEVICE, &addr)) | |
1ce9e605 TB |
1317 | goto unmap_release; |
1318 | ||
1319 | desc[i].flags = cpu_to_le16(n < out_sgs ? | |
1320 | 0 : VRING_DESC_F_WRITE); | |
1321 | desc[i].addr = cpu_to_le64(addr); | |
1322 | desc[i].len = cpu_to_le32(sg->length); | |
1323 | i++; | |
1324 | } | |
1325 | } | |
1326 | ||
1327 | /* Now that the indirect table is filled in, map it. */ | |
1328 | addr = vring_map_single(vq, desc, | |
1329 | total_sg * sizeof(struct vring_packed_desc), | |
1330 | DMA_TO_DEVICE); | |
d7344a2f XZ |
1331 | if (vring_mapping_error(vq, addr)) { |
1332 | if (vq->premapped) | |
1333 | goto free_desc; | |
1334 | ||
1ce9e605 | 1335 | goto unmap_release; |
d7344a2f | 1336 | } |
1ce9e605 TB |
1337 | |
1338 | vq->packed.vring.desc[head].addr = cpu_to_le64(addr); | |
1339 | vq->packed.vring.desc[head].len = cpu_to_le32(total_sg * | |
1340 | sizeof(struct vring_packed_desc)); | |
1341 | vq->packed.vring.desc[head].id = cpu_to_le16(id); | |
1342 | ||
b319940f | 1343 | if (vq->do_unmap) { |
1ce9e605 TB |
1344 | vq->packed.desc_extra[id].addr = addr; |
1345 | vq->packed.desc_extra[id].len = total_sg * | |
1346 | sizeof(struct vring_packed_desc); | |
1347 | vq->packed.desc_extra[id].flags = VRING_DESC_F_INDIRECT | | |
1348 | vq->packed.avail_used_flags; | |
1349 | } | |
1350 | ||
1351 | /* | |
1352 | * A driver MUST NOT make the first descriptor in the list | |
1353 | * available before all subsequent descriptors comprising | |
1354 | * the list are made available. | |
1355 | */ | |
1356 | virtio_wmb(vq->weak_barriers); | |
1357 | vq->packed.vring.desc[head].flags = cpu_to_le16(VRING_DESC_F_INDIRECT | | |
1358 | vq->packed.avail_used_flags); | |
1359 | ||
1360 | /* We're using some buffers from the free list. */ | |
1361 | vq->vq.num_free -= 1; | |
1362 | ||
1363 | /* Update free pointer */ | |
1364 | n = head + 1; | |
1365 | if (n >= vq->packed.vring.num) { | |
1366 | n = 0; | |
1367 | vq->packed.avail_wrap_counter ^= 1; | |
1368 | vq->packed.avail_used_flags ^= | |
1369 | 1 << VRING_PACKED_DESC_F_AVAIL | | |
1370 | 1 << VRING_PACKED_DESC_F_USED; | |
1371 | } | |
1372 | vq->packed.next_avail_idx = n; | |
aeef9b47 | 1373 | vq->free_head = vq->packed.desc_extra[id].next; |
1ce9e605 TB |
1374 | |
1375 | /* Store token and indirect buffer state. */ | |
1376 | vq->packed.desc_state[id].num = 1; | |
1377 | vq->packed.desc_state[id].data = data; | |
1378 | vq->packed.desc_state[id].indir_desc = desc; | |
1379 | vq->packed.desc_state[id].last = id; | |
1380 | ||
1381 | vq->num_added += 1; | |
1382 | ||
1383 | pr_debug("Added buffer head %i to %p\n", head, vq); | |
1384 | END_USE(vq); | |
1385 | ||
1386 | return 0; | |
1387 | ||
1388 | unmap_release: | |
1389 | err_idx = i; | |
1390 | ||
1391 | for (i = 0; i < err_idx; i++) | |
1392 | vring_unmap_desc_packed(vq, &desc[i]); | |
1393 | ||
d7344a2f | 1394 | free_desc: |
1ce9e605 TB |
1395 | kfree(desc); |
1396 | ||
1397 | END_USE(vq); | |
f7728002 | 1398 | return -ENOMEM; |
1ce9e605 TB |
1399 | } |
1400 | ||
1401 | static inline int virtqueue_add_packed(struct virtqueue *_vq, | |
1402 | struct scatterlist *sgs[], | |
1403 | unsigned int total_sg, | |
1404 | unsigned int out_sgs, | |
1405 | unsigned int in_sgs, | |
1406 | void *data, | |
1407 | void *ctx, | |
1408 | gfp_t gfp) | |
1409 | { | |
1410 | struct vring_virtqueue *vq = to_vvq(_vq); | |
1411 | struct vring_packed_desc *desc; | |
1412 | struct scatterlist *sg; | |
1413 | unsigned int i, n, c, descs_used, err_idx; | |
3f649ab7 KC |
1414 | __le16 head_flags, flags; |
1415 | u16 head, id, prev, curr, avail_used_flags; | |
fc6d70f4 | 1416 | int err; |
1ce9e605 TB |
1417 | |
1418 | START_USE(vq); | |
1419 | ||
1420 | BUG_ON(data == NULL); | |
1421 | BUG_ON(ctx && vq->indirect); | |
1422 | ||
1423 | if (unlikely(vq->broken)) { | |
1424 | END_USE(vq); | |
1425 | return -EIO; | |
1426 | } | |
1427 | ||
1428 | LAST_ADD_TIME_UPDATE(vq); | |
1429 | ||
1430 | BUG_ON(total_sg == 0); | |
1431 | ||
35c51e09 | 1432 | if (virtqueue_use_indirect(vq, total_sg)) { |
fc6d70f4 XZ |
1433 | err = virtqueue_add_indirect_packed(vq, sgs, total_sg, out_sgs, |
1434 | in_sgs, data, gfp); | |
1861ba62 MT |
1435 | if (err != -ENOMEM) { |
1436 | END_USE(vq); | |
fc6d70f4 | 1437 | return err; |
1861ba62 | 1438 | } |
fc6d70f4 XZ |
1439 | |
1440 | /* fall back on direct */ | |
1441 | } | |
1ce9e605 TB |
1442 | |
1443 | head = vq->packed.next_avail_idx; | |
1444 | avail_used_flags = vq->packed.avail_used_flags; | |
1445 | ||
1446 | WARN_ON_ONCE(total_sg > vq->packed.vring.num && !vq->indirect); | |
1447 | ||
1448 | desc = vq->packed.vring.desc; | |
1449 | i = head; | |
1450 | descs_used = total_sg; | |
1451 | ||
1452 | if (unlikely(vq->vq.num_free < descs_used)) { | |
1453 | pr_debug("Can't add buf len %i - avail = %i\n", | |
1454 | descs_used, vq->vq.num_free); | |
1455 | END_USE(vq); | |
1456 | return -ENOSPC; | |
1457 | } | |
1458 | ||
1459 | id = vq->free_head; | |
1460 | BUG_ON(id == vq->packed.vring.num); | |
1461 | ||
1462 | curr = id; | |
1463 | c = 0; | |
1464 | for (n = 0; n < out_sgs + in_sgs; n++) { | |
1465 | for (sg = sgs[n]; sg; sg = sg_next(sg)) { | |
0e27fa6d XZ |
1466 | dma_addr_t addr; |
1467 | ||
1468 | if (vring_map_one_sg(vq, sg, n < out_sgs ? | |
1469 | DMA_TO_DEVICE : DMA_FROM_DEVICE, &addr)) | |
1ce9e605 TB |
1470 | goto unmap_release; |
1471 | ||
1472 | flags = cpu_to_le16(vq->packed.avail_used_flags | | |
1473 | (++c == total_sg ? 0 : VRING_DESC_F_NEXT) | | |
1474 | (n < out_sgs ? 0 : VRING_DESC_F_WRITE)); | |
1475 | if (i == head) | |
1476 | head_flags = flags; | |
1477 | else | |
1478 | desc[i].flags = flags; | |
1479 | ||
1480 | desc[i].addr = cpu_to_le64(addr); | |
1481 | desc[i].len = cpu_to_le32(sg->length); | |
1482 | desc[i].id = cpu_to_le16(id); | |
1483 | ||
b319940f | 1484 | if (unlikely(vq->do_unmap)) { |
1ce9e605 TB |
1485 | vq->packed.desc_extra[curr].addr = addr; |
1486 | vq->packed.desc_extra[curr].len = sg->length; | |
1487 | vq->packed.desc_extra[curr].flags = | |
1488 | le16_to_cpu(flags); | |
1489 | } | |
1490 | prev = curr; | |
aeef9b47 | 1491 | curr = vq->packed.desc_extra[curr].next; |
1ce9e605 TB |
1492 | |
1493 | if ((unlikely(++i >= vq->packed.vring.num))) { | |
1494 | i = 0; | |
1495 | vq->packed.avail_used_flags ^= | |
1496 | 1 << VRING_PACKED_DESC_F_AVAIL | | |
1497 | 1 << VRING_PACKED_DESC_F_USED; | |
1498 | } | |
1499 | } | |
1500 | } | |
1501 | ||
1502 | if (i < head) | |
1503 | vq->packed.avail_wrap_counter ^= 1; | |
1504 | ||
1505 | /* We're using some buffers from the free list. */ | |
1506 | vq->vq.num_free -= descs_used; | |
1507 | ||
1508 | /* Update free pointer */ | |
1509 | vq->packed.next_avail_idx = i; | |
1510 | vq->free_head = curr; | |
1511 | ||
1512 | /* Store token. */ | |
1513 | vq->packed.desc_state[id].num = descs_used; | |
1514 | vq->packed.desc_state[id].data = data; | |
1515 | vq->packed.desc_state[id].indir_desc = ctx; | |
1516 | vq->packed.desc_state[id].last = prev; | |
1517 | ||
1518 | /* | |
1519 | * A driver MUST NOT make the first descriptor in the list | |
1520 | * available before all subsequent descriptors comprising | |
1521 | * the list are made available. | |
1522 | */ | |
1523 | virtio_wmb(vq->weak_barriers); | |
1524 | vq->packed.vring.desc[head].flags = head_flags; | |
1525 | vq->num_added += descs_used; | |
1526 | ||
1527 | pr_debug("Added buffer head %i to %p\n", head, vq); | |
1528 | END_USE(vq); | |
1529 | ||
1530 | return 0; | |
1531 | ||
1532 | unmap_release: | |
1533 | err_idx = i; | |
1534 | i = head; | |
44593865 | 1535 | curr = vq->free_head; |
1ce9e605 TB |
1536 | |
1537 | vq->packed.avail_used_flags = avail_used_flags; | |
1538 | ||
1539 | for (n = 0; n < total_sg; n++) { | |
1540 | if (i == err_idx) | |
1541 | break; | |
d80dc15b | 1542 | vring_unmap_extra_packed(vq, &vq->packed.desc_extra[curr]); |
44593865 | 1543 | curr = vq->packed.desc_extra[curr].next; |
1ce9e605 TB |
1544 | i++; |
1545 | if (i >= vq->packed.vring.num) | |
1546 | i = 0; | |
1547 | } | |
1548 | ||
1549 | END_USE(vq); | |
1550 | return -EIO; | |
1551 | } | |
1552 | ||
1553 | static bool virtqueue_kick_prepare_packed(struct virtqueue *_vq) | |
1554 | { | |
1555 | struct vring_virtqueue *vq = to_vvq(_vq); | |
f51f9826 | 1556 | u16 new, old, off_wrap, flags, wrap_counter, event_idx; |
1ce9e605 TB |
1557 | bool needs_kick; |
1558 | union { | |
1559 | struct { | |
1560 | __le16 off_wrap; | |
1561 | __le16 flags; | |
1562 | }; | |
1563 | u32 u32; | |
1564 | } snapshot; | |
1565 | ||
1566 | START_USE(vq); | |
1567 | ||
1568 | /* | |
1569 | * We need to expose the new flags value before checking notification | |
1570 | * suppressions. | |
1571 | */ | |
1572 | virtio_mb(vq->weak_barriers); | |
1573 | ||
f51f9826 TB |
1574 | old = vq->packed.next_avail_idx - vq->num_added; |
1575 | new = vq->packed.next_avail_idx; | |
1ce9e605 TB |
1576 | vq->num_added = 0; |
1577 | ||
1578 | snapshot.u32 = *(u32 *)vq->packed.vring.device; | |
1579 | flags = le16_to_cpu(snapshot.flags); | |
1580 | ||
1581 | LAST_ADD_TIME_CHECK(vq); | |
1582 | LAST_ADD_TIME_INVALID(vq); | |
1583 | ||
f51f9826 TB |
1584 | if (flags != VRING_PACKED_EVENT_FLAG_DESC) { |
1585 | needs_kick = (flags != VRING_PACKED_EVENT_FLAG_DISABLE); | |
1586 | goto out; | |
1587 | } | |
1588 | ||
1589 | off_wrap = le16_to_cpu(snapshot.off_wrap); | |
1590 | ||
1591 | wrap_counter = off_wrap >> VRING_PACKED_EVENT_F_WRAP_CTR; | |
1592 | event_idx = off_wrap & ~(1 << VRING_PACKED_EVENT_F_WRAP_CTR); | |
1593 | if (wrap_counter != vq->packed.avail_wrap_counter) | |
1594 | event_idx -= vq->packed.vring.num; | |
1595 | ||
1596 | needs_kick = vring_need_event(event_idx, new, old); | |
1597 | out: | |
1ce9e605 TB |
1598 | END_USE(vq); |
1599 | return needs_kick; | |
1600 | } | |
1601 | ||
1602 | static void detach_buf_packed(struct vring_virtqueue *vq, | |
1603 | unsigned int id, void **ctx) | |
1604 | { | |
1605 | struct vring_desc_state_packed *state = NULL; | |
1606 | struct vring_packed_desc *desc; | |
1607 | unsigned int i, curr; | |
1608 | ||
1609 | state = &vq->packed.desc_state[id]; | |
1610 | ||
1611 | /* Clear data ptr. */ | |
1612 | state->data = NULL; | |
1613 | ||
aeef9b47 | 1614 | vq->packed.desc_extra[state->last].next = vq->free_head; |
1ce9e605 TB |
1615 | vq->free_head = id; |
1616 | vq->vq.num_free += state->num; | |
1617 | ||
b319940f | 1618 | if (unlikely(vq->do_unmap)) { |
1ce9e605 TB |
1619 | curr = id; |
1620 | for (i = 0; i < state->num; i++) { | |
d80dc15b XZ |
1621 | vring_unmap_extra_packed(vq, |
1622 | &vq->packed.desc_extra[curr]); | |
aeef9b47 | 1623 | curr = vq->packed.desc_extra[curr].next; |
1ce9e605 TB |
1624 | } |
1625 | } | |
1626 | ||
1627 | if (vq->indirect) { | |
1628 | u32 len; | |
1629 | ||
1630 | /* Free the indirect table, if any, now that it's unmapped. */ | |
1631 | desc = state->indir_desc; | |
1632 | if (!desc) | |
1633 | return; | |
1634 | ||
b319940f | 1635 | if (vq->do_unmap) { |
1ce9e605 TB |
1636 | len = vq->packed.desc_extra[id].len; |
1637 | for (i = 0; i < len / sizeof(struct vring_packed_desc); | |
1638 | i++) | |
1639 | vring_unmap_desc_packed(vq, &desc[i]); | |
1640 | } | |
1641 | kfree(desc); | |
1642 | state->indir_desc = NULL; | |
1643 | } else if (ctx) { | |
1644 | *ctx = state->indir_desc; | |
1645 | } | |
1646 | } | |
1647 | ||
1648 | static inline bool is_used_desc_packed(const struct vring_virtqueue *vq, | |
1649 | u16 idx, bool used_wrap_counter) | |
1650 | { | |
1651 | bool avail, used; | |
1652 | u16 flags; | |
1653 | ||
1654 | flags = le16_to_cpu(vq->packed.vring.desc[idx].flags); | |
1655 | avail = !!(flags & (1 << VRING_PACKED_DESC_F_AVAIL)); | |
1656 | used = !!(flags & (1 << VRING_PACKED_DESC_F_USED)); | |
1657 | ||
1658 | return avail == used && used == used_wrap_counter; | |
1659 | } | |
1660 | ||
1adbd6b2 | 1661 | static bool more_used_packed(const struct vring_virtqueue *vq) |
1ce9e605 | 1662 | { |
a7722890 | 1663 | u16 last_used; |
1664 | u16 last_used_idx; | |
1665 | bool used_wrap_counter; | |
1666 | ||
1667 | last_used_idx = READ_ONCE(vq->last_used_idx); | |
1668 | last_used = packed_last_used(last_used_idx); | |
1669 | used_wrap_counter = packed_used_wrap_counter(last_used_idx); | |
1670 | return is_used_desc_packed(vq, last_used, used_wrap_counter); | |
1ce9e605 TB |
1671 | } |
1672 | ||
1673 | static void *virtqueue_get_buf_ctx_packed(struct virtqueue *_vq, | |
1674 | unsigned int *len, | |
1675 | void **ctx) | |
1676 | { | |
1677 | struct vring_virtqueue *vq = to_vvq(_vq); | |
a7722890 | 1678 | u16 last_used, id, last_used_idx; |
1679 | bool used_wrap_counter; | |
1ce9e605 TB |
1680 | void *ret; |
1681 | ||
1682 | START_USE(vq); | |
1683 | ||
1684 | if (unlikely(vq->broken)) { | |
1685 | END_USE(vq); | |
1686 | return NULL; | |
1687 | } | |
1688 | ||
1689 | if (!more_used_packed(vq)) { | |
1690 | pr_debug("No more buffers in queue\n"); | |
1691 | END_USE(vq); | |
1692 | return NULL; | |
1693 | } | |
1694 | ||
1695 | /* Only get used elements after they have been exposed by host. */ | |
1696 | virtio_rmb(vq->weak_barriers); | |
1697 | ||
a7722890 | 1698 | last_used_idx = READ_ONCE(vq->last_used_idx); |
1699 | used_wrap_counter = packed_used_wrap_counter(last_used_idx); | |
1700 | last_used = packed_last_used(last_used_idx); | |
1ce9e605 TB |
1701 | id = le16_to_cpu(vq->packed.vring.desc[last_used].id); |
1702 | *len = le32_to_cpu(vq->packed.vring.desc[last_used].len); | |
1703 | ||
1704 | if (unlikely(id >= vq->packed.vring.num)) { | |
1705 | BAD_RING(vq, "id %u out of range\n", id); | |
1706 | return NULL; | |
1707 | } | |
1708 | if (unlikely(!vq->packed.desc_state[id].data)) { | |
1709 | BAD_RING(vq, "id %u is not a head!\n", id); | |
1710 | return NULL; | |
1711 | } | |
1712 | ||
1713 | /* detach_buf_packed clears data, so grab it now. */ | |
1714 | ret = vq->packed.desc_state[id].data; | |
1715 | detach_buf_packed(vq, id, ctx); | |
1716 | ||
a7722890 | 1717 | last_used += vq->packed.desc_state[id].num; |
1718 | if (unlikely(last_used >= vq->packed.vring.num)) { | |
1719 | last_used -= vq->packed.vring.num; | |
1720 | used_wrap_counter ^= 1; | |
1ce9e605 TB |
1721 | } |
1722 | ||
a7722890 | 1723 | last_used = (last_used | (used_wrap_counter << VRING_PACKED_EVENT_F_WRAP_CTR)); |
1724 | WRITE_ONCE(vq->last_used_idx, last_used); | |
1725 | ||
f51f9826 TB |
1726 | /* |
1727 | * If we expect an interrupt for the next entry, tell host | |
1728 | * by writing event index and flush out the write before | |
1729 | * the read in the next get_buf call. | |
1730 | */ | |
1731 | if (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DESC) | |
1732 | virtio_store_mb(vq->weak_barriers, | |
1733 | &vq->packed.vring.driver->off_wrap, | |
a7722890 | 1734 | cpu_to_le16(vq->last_used_idx)); |
f51f9826 | 1735 | |
1ce9e605 TB |
1736 | LAST_ADD_TIME_INVALID(vq); |
1737 | ||
1738 | END_USE(vq); | |
1739 | return ret; | |
1740 | } | |
1741 | ||
1742 | static void virtqueue_disable_cb_packed(struct virtqueue *_vq) | |
1743 | { | |
1744 | struct vring_virtqueue *vq = to_vvq(_vq); | |
1745 | ||
1746 | if (vq->packed.event_flags_shadow != VRING_PACKED_EVENT_FLAG_DISABLE) { | |
1747 | vq->packed.event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE; | |
6c0b057c AH |
1748 | |
1749 | /* | |
1750 | * If device triggered an event already it won't trigger one again: | |
1751 | * no need to disable. | |
1752 | */ | |
1753 | if (vq->event_triggered) | |
1754 | return; | |
1755 | ||
1ce9e605 TB |
1756 | vq->packed.vring.driver->flags = |
1757 | cpu_to_le16(vq->packed.event_flags_shadow); | |
1758 | } | |
1759 | } | |
1760 | ||
31532340 | 1761 | static unsigned int virtqueue_enable_cb_prepare_packed(struct virtqueue *_vq) |
1ce9e605 TB |
1762 | { |
1763 | struct vring_virtqueue *vq = to_vvq(_vq); | |
1764 | ||
1765 | START_USE(vq); | |
1766 | ||
1767 | /* | |
1768 | * We optimistically turn back on interrupts, then check if there was | |
1769 | * more to do. | |
1770 | */ | |
1771 | ||
f51f9826 TB |
1772 | if (vq->event) { |
1773 | vq->packed.vring.driver->off_wrap = | |
a7722890 | 1774 | cpu_to_le16(vq->last_used_idx); |
f51f9826 TB |
1775 | /* |
1776 | * We need to update event offset and event wrap | |
1777 | * counter first before updating event flags. | |
1778 | */ | |
1779 | virtio_wmb(vq->weak_barriers); | |
1780 | } | |
1781 | ||
1ce9e605 | 1782 | if (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DISABLE) { |
f51f9826 TB |
1783 | vq->packed.event_flags_shadow = vq->event ? |
1784 | VRING_PACKED_EVENT_FLAG_DESC : | |
1785 | VRING_PACKED_EVENT_FLAG_ENABLE; | |
1ce9e605 TB |
1786 | vq->packed.vring.driver->flags = |
1787 | cpu_to_le16(vq->packed.event_flags_shadow); | |
1788 | } | |
1789 | ||
1790 | END_USE(vq); | |
a7722890 | 1791 | return vq->last_used_idx; |
1ce9e605 TB |
1792 | } |
1793 | ||
1794 | static bool virtqueue_poll_packed(struct virtqueue *_vq, u16 off_wrap) | |
1795 | { | |
1796 | struct vring_virtqueue *vq = to_vvq(_vq); | |
1797 | bool wrap_counter; | |
1798 | u16 used_idx; | |
1799 | ||
1800 | wrap_counter = off_wrap >> VRING_PACKED_EVENT_F_WRAP_CTR; | |
1801 | used_idx = off_wrap & ~(1 << VRING_PACKED_EVENT_F_WRAP_CTR); | |
1802 | ||
1803 | return is_used_desc_packed(vq, used_idx, wrap_counter); | |
1804 | } | |
1805 | ||
1806 | static bool virtqueue_enable_cb_delayed_packed(struct virtqueue *_vq) | |
1807 | { | |
1808 | struct vring_virtqueue *vq = to_vvq(_vq); | |
a7722890 | 1809 | u16 used_idx, wrap_counter, last_used_idx; |
f51f9826 | 1810 | u16 bufs; |
1ce9e605 TB |
1811 | |
1812 | START_USE(vq); | |
1813 | ||
1814 | /* | |
1815 | * We optimistically turn back on interrupts, then check if there was | |
1816 | * more to do. | |
1817 | */ | |
1818 | ||
f51f9826 TB |
1819 | if (vq->event) { |
1820 | /* TODO: tune this threshold */ | |
1821 | bufs = (vq->packed.vring.num - vq->vq.num_free) * 3 / 4; | |
a7722890 | 1822 | last_used_idx = READ_ONCE(vq->last_used_idx); |
1823 | wrap_counter = packed_used_wrap_counter(last_used_idx); | |
f51f9826 | 1824 | |
a7722890 | 1825 | used_idx = packed_last_used(last_used_idx) + bufs; |
f51f9826 TB |
1826 | if (used_idx >= vq->packed.vring.num) { |
1827 | used_idx -= vq->packed.vring.num; | |
1828 | wrap_counter ^= 1; | |
1829 | } | |
1830 | ||
1831 | vq->packed.vring.driver->off_wrap = cpu_to_le16(used_idx | | |
1832 | (wrap_counter << VRING_PACKED_EVENT_F_WRAP_CTR)); | |
1833 | ||
1834 | /* | |
1835 | * We need to update event offset and event wrap | |
1836 | * counter first before updating event flags. | |
1837 | */ | |
1838 | virtio_wmb(vq->weak_barriers); | |
f51f9826 | 1839 | } |
1ce9e605 TB |
1840 | |
1841 | if (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DISABLE) { | |
f51f9826 TB |
1842 | vq->packed.event_flags_shadow = vq->event ? |
1843 | VRING_PACKED_EVENT_FLAG_DESC : | |
1844 | VRING_PACKED_EVENT_FLAG_ENABLE; | |
1ce9e605 TB |
1845 | vq->packed.vring.driver->flags = |
1846 | cpu_to_le16(vq->packed.event_flags_shadow); | |
1847 | } | |
1848 | ||
1849 | /* | |
1850 | * We need to update event suppression structure first | |
1851 | * before re-checking for more used buffers. | |
1852 | */ | |
1853 | virtio_mb(vq->weak_barriers); | |
1854 | ||
a7722890 | 1855 | last_used_idx = READ_ONCE(vq->last_used_idx); |
1856 | wrap_counter = packed_used_wrap_counter(last_used_idx); | |
1857 | used_idx = packed_last_used(last_used_idx); | |
1858 | if (is_used_desc_packed(vq, used_idx, wrap_counter)) { | |
1ce9e605 TB |
1859 | END_USE(vq); |
1860 | return false; | |
1861 | } | |
1862 | ||
1863 | END_USE(vq); | |
1864 | return true; | |
1865 | } | |
1866 | ||
1867 | static void *virtqueue_detach_unused_buf_packed(struct virtqueue *_vq) | |
1868 | { | |
1869 | struct vring_virtqueue *vq = to_vvq(_vq); | |
1870 | unsigned int i; | |
1871 | void *buf; | |
1872 | ||
1873 | START_USE(vq); | |
1874 | ||
1875 | for (i = 0; i < vq->packed.vring.num; i++) { | |
1876 | if (!vq->packed.desc_state[i].data) | |
1877 | continue; | |
1878 | /* detach_buf clears data, so grab it now. */ | |
1879 | buf = vq->packed.desc_state[i].data; | |
1880 | detach_buf_packed(vq, i, NULL); | |
1881 | END_USE(vq); | |
1882 | return buf; | |
1883 | } | |
1884 | /* That should have freed everything. */ | |
1885 | BUG_ON(vq->vq.num_free != vq->packed.vring.num); | |
1886 | ||
1887 | END_USE(vq); | |
1888 | return NULL; | |
1889 | } | |
1890 | ||
96ef18a2 | 1891 | static struct vring_desc_extra *vring_alloc_desc_extra(unsigned int num) |
5a222421 JW |
1892 | { |
1893 | struct vring_desc_extra *desc_extra; | |
1894 | unsigned int i; | |
1895 | ||
1896 | desc_extra = kmalloc_array(num, sizeof(struct vring_desc_extra), | |
1897 | GFP_KERNEL); | |
1898 | if (!desc_extra) | |
1899 | return NULL; | |
1900 | ||
1901 | memset(desc_extra, 0, num * sizeof(struct vring_desc_extra)); | |
1902 | ||
1903 | for (i = 0; i < num - 1; i++) | |
1904 | desc_extra[i].next = i + 1; | |
1905 | ||
1906 | return desc_extra; | |
1907 | } | |
1908 | ||
6356f8bb | 1909 | static void vring_free_packed(struct vring_virtqueue_packed *vring_packed, |
2713ea3c JW |
1910 | struct virtio_device *vdev, |
1911 | struct device *dma_dev) | |
6356f8bb XZ |
1912 | { |
1913 | if (vring_packed->vring.desc) | |
1914 | vring_free_queue(vdev, vring_packed->ring_size_in_bytes, | |
1915 | vring_packed->vring.desc, | |
2713ea3c JW |
1916 | vring_packed->ring_dma_addr, |
1917 | dma_dev); | |
6356f8bb XZ |
1918 | |
1919 | if (vring_packed->vring.driver) | |
1920 | vring_free_queue(vdev, vring_packed->event_size_in_bytes, | |
1921 | vring_packed->vring.driver, | |
2713ea3c JW |
1922 | vring_packed->driver_event_dma_addr, |
1923 | dma_dev); | |
6356f8bb XZ |
1924 | |
1925 | if (vring_packed->vring.device) | |
1926 | vring_free_queue(vdev, vring_packed->event_size_in_bytes, | |
1927 | vring_packed->vring.device, | |
2713ea3c JW |
1928 | vring_packed->device_event_dma_addr, |
1929 | dma_dev); | |
6356f8bb XZ |
1930 | |
1931 | kfree(vring_packed->desc_state); | |
1932 | kfree(vring_packed->desc_extra); | |
1933 | } | |
1934 | ||
6b60b9c0 XZ |
1935 | static int vring_alloc_queue_packed(struct vring_virtqueue_packed *vring_packed, |
1936 | struct virtio_device *vdev, | |
2713ea3c | 1937 | u32 num, struct device *dma_dev) |
1ce9e605 | 1938 | { |
1ce9e605 TB |
1939 | struct vring_packed_desc *ring; |
1940 | struct vring_packed_desc_event *driver, *device; | |
1941 | dma_addr_t ring_dma_addr, driver_event_dma_addr, device_event_dma_addr; | |
1942 | size_t ring_size_in_bytes, event_size_in_bytes; | |
1ce9e605 TB |
1943 | |
1944 | ring_size_in_bytes = num * sizeof(struct vring_packed_desc); | |
1945 | ||
1946 | ring = vring_alloc_queue(vdev, ring_size_in_bytes, | |
1947 | &ring_dma_addr, | |
2713ea3c JW |
1948 | GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO, |
1949 | dma_dev); | |
1ce9e605 | 1950 | if (!ring) |
6b60b9c0 XZ |
1951 | goto err; |
1952 | ||
1953 | vring_packed->vring.desc = ring; | |
1954 | vring_packed->ring_dma_addr = ring_dma_addr; | |
1955 | vring_packed->ring_size_in_bytes = ring_size_in_bytes; | |
1ce9e605 TB |
1956 | |
1957 | event_size_in_bytes = sizeof(struct vring_packed_desc_event); | |
1958 | ||
1959 | driver = vring_alloc_queue(vdev, event_size_in_bytes, | |
1960 | &driver_event_dma_addr, | |
2713ea3c JW |
1961 | GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO, |
1962 | dma_dev); | |
1ce9e605 | 1963 | if (!driver) |
6b60b9c0 XZ |
1964 | goto err; |
1965 | ||
1966 | vring_packed->vring.driver = driver; | |
1967 | vring_packed->event_size_in_bytes = event_size_in_bytes; | |
1968 | vring_packed->driver_event_dma_addr = driver_event_dma_addr; | |
1ce9e605 TB |
1969 | |
1970 | device = vring_alloc_queue(vdev, event_size_in_bytes, | |
1971 | &device_event_dma_addr, | |
2713ea3c JW |
1972 | GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO, |
1973 | dma_dev); | |
1ce9e605 | 1974 | if (!device) |
6b60b9c0 XZ |
1975 | goto err; |
1976 | ||
1977 | vring_packed->vring.device = device; | |
1978 | vring_packed->device_event_dma_addr = device_event_dma_addr; | |
1979 | ||
1980 | vring_packed->vring.num = num; | |
1981 | ||
1982 | return 0; | |
1983 | ||
1984 | err: | |
2713ea3c | 1985 | vring_free_packed(vring_packed, vdev, dma_dev); |
6b60b9c0 XZ |
1986 | return -ENOMEM; |
1987 | } | |
1988 | ||
ef3167cf XZ |
1989 | static int vring_alloc_state_extra_packed(struct vring_virtqueue_packed *vring_packed) |
1990 | { | |
1991 | struct vring_desc_state_packed *state; | |
1992 | struct vring_desc_extra *extra; | |
1993 | u32 num = vring_packed->vring.num; | |
1994 | ||
1995 | state = kmalloc_array(num, sizeof(struct vring_desc_state_packed), GFP_KERNEL); | |
1996 | if (!state) | |
1997 | goto err_desc_state; | |
1998 | ||
1999 | memset(state, 0, num * sizeof(struct vring_desc_state_packed)); | |
2000 | ||
2001 | extra = vring_alloc_desc_extra(num); | |
2002 | if (!extra) | |
2003 | goto err_desc_extra; | |
2004 | ||
2005 | vring_packed->desc_state = state; | |
2006 | vring_packed->desc_extra = extra; | |
2007 | ||
2008 | return 0; | |
2009 | ||
2010 | err_desc_extra: | |
2011 | kfree(state); | |
2012 | err_desc_state: | |
2013 | return -ENOMEM; | |
2014 | } | |
2015 | ||
1a107c87 XZ |
2016 | static void virtqueue_vring_init_packed(struct vring_virtqueue_packed *vring_packed, |
2017 | bool callback) | |
2018 | { | |
2019 | vring_packed->next_avail_idx = 0; | |
2020 | vring_packed->avail_wrap_counter = 1; | |
2021 | vring_packed->event_flags_shadow = 0; | |
2022 | vring_packed->avail_used_flags = 1 << VRING_PACKED_DESC_F_AVAIL; | |
2023 | ||
2024 | /* No callback? Tell other side not to bother us. */ | |
2025 | if (!callback) { | |
2026 | vring_packed->event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE; | |
2027 | vring_packed->vring.driver->flags = | |
2028 | cpu_to_le16(vring_packed->event_flags_shadow); | |
2029 | } | |
2030 | } | |
2031 | ||
51d649f1 XZ |
2032 | static void virtqueue_vring_attach_packed(struct vring_virtqueue *vq, |
2033 | struct vring_virtqueue_packed *vring_packed) | |
2034 | { | |
2035 | vq->packed = *vring_packed; | |
2036 | ||
2037 | /* Put everything in free lists. */ | |
2038 | vq->free_head = 0; | |
2039 | } | |
2040 | ||
56775e14 XZ |
2041 | static void virtqueue_reinit_packed(struct vring_virtqueue *vq) |
2042 | { | |
2043 | memset(vq->packed.vring.device, 0, vq->packed.event_size_in_bytes); | |
2044 | memset(vq->packed.vring.driver, 0, vq->packed.event_size_in_bytes); | |
2045 | ||
2046 | /* we need to reset the desc.flags. For more, see is_used_desc_packed() */ | |
2047 | memset(vq->packed.vring.desc, 0, vq->packed.ring_size_in_bytes); | |
2048 | ||
2049 | virtqueue_init(vq, vq->packed.vring.num); | |
2050 | virtqueue_vring_init_packed(&vq->packed, !!vq->vq.callback); | |
2051 | } | |
2052 | ||
6b60b9c0 XZ |
2053 | static struct virtqueue *vring_create_virtqueue_packed( |
2054 | unsigned int index, | |
2055 | unsigned int num, | |
2056 | unsigned int vring_align, | |
2057 | struct virtio_device *vdev, | |
2058 | bool weak_barriers, | |
2059 | bool may_reduce_num, | |
2060 | bool context, | |
2061 | bool (*notify)(struct virtqueue *), | |
2062 | void (*callback)(struct virtqueue *), | |
2713ea3c JW |
2063 | const char *name, |
2064 | struct device *dma_dev) | |
6b60b9c0 XZ |
2065 | { |
2066 | struct vring_virtqueue_packed vring_packed = {}; | |
2067 | struct vring_virtqueue *vq; | |
ef3167cf | 2068 | int err; |
6b60b9c0 | 2069 | |
2713ea3c | 2070 | if (vring_alloc_queue_packed(&vring_packed, vdev, num, dma_dev)) |
6b60b9c0 | 2071 | goto err_ring; |
1ce9e605 TB |
2072 | |
2073 | vq = kmalloc(sizeof(*vq), GFP_KERNEL); | |
2074 | if (!vq) | |
2075 | goto err_vq; | |
2076 | ||
2077 | vq->vq.callback = callback; | |
2078 | vq->vq.vdev = vdev; | |
2079 | vq->vq.name = name; | |
1ce9e605 | 2080 | vq->vq.index = index; |
4913e854 | 2081 | vq->vq.reset = false; |
1ce9e605 TB |
2082 | vq->we_own_ring = true; |
2083 | vq->notify = notify; | |
2084 | vq->weak_barriers = weak_barriers; | |
c346dae4 | 2085 | #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION |
8b4ec69d | 2086 | vq->broken = true; |
c346dae4 JW |
2087 | #else |
2088 | vq->broken = false; | |
2089 | #endif | |
1ce9e605 | 2090 | vq->packed_ring = true; |
2713ea3c | 2091 | vq->dma_dev = dma_dev; |
1ce9e605 | 2092 | vq->use_dma_api = vring_use_dma_api(vdev); |
8daafe9e | 2093 | vq->premapped = false; |
b319940f | 2094 | vq->do_unmap = vq->use_dma_api; |
1ce9e605 TB |
2095 | |
2096 | vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) && | |
2097 | !context; | |
2098 | vq->event = virtio_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX); | |
2099 | ||
45383fb0 TB |
2100 | if (virtio_has_feature(vdev, VIRTIO_F_ORDER_PLATFORM)) |
2101 | vq->weak_barriers = false; | |
2102 | ||
ef3167cf XZ |
2103 | err = vring_alloc_state_extra_packed(&vring_packed); |
2104 | if (err) | |
2105 | goto err_state_extra; | |
1ce9e605 | 2106 | |
1a107c87 | 2107 | virtqueue_vring_init_packed(&vring_packed, !!callback); |
1ce9e605 | 2108 | |
3a897128 | 2109 | virtqueue_init(vq, num); |
51d649f1 | 2110 | virtqueue_vring_attach_packed(vq, &vring_packed); |
3a897128 | 2111 | |
0e566c8f | 2112 | spin_lock(&vdev->vqs_list_lock); |
e152d8af | 2113 | list_add_tail(&vq->vq.list, &vdev->vqs); |
0e566c8f | 2114 | spin_unlock(&vdev->vqs_list_lock); |
1ce9e605 TB |
2115 | return &vq->vq; |
2116 | ||
ef3167cf | 2117 | err_state_extra: |
1ce9e605 TB |
2118 | kfree(vq); |
2119 | err_vq: | |
2713ea3c | 2120 | vring_free_packed(&vring_packed, vdev, dma_dev); |
1ce9e605 TB |
2121 | err_ring: |
2122 | return NULL; | |
2123 | } | |
2124 | ||
947f9fcf XZ |
2125 | static int virtqueue_resize_packed(struct virtqueue *_vq, u32 num) |
2126 | { | |
2127 | struct vring_virtqueue_packed vring_packed = {}; | |
2128 | struct vring_virtqueue *vq = to_vvq(_vq); | |
2129 | struct virtio_device *vdev = _vq->vdev; | |
2130 | int err; | |
2131 | ||
2713ea3c | 2132 | if (vring_alloc_queue_packed(&vring_packed, vdev, num, vring_dma_dev(vq))) |
947f9fcf XZ |
2133 | goto err_ring; |
2134 | ||
2135 | err = vring_alloc_state_extra_packed(&vring_packed); | |
2136 | if (err) | |
2137 | goto err_state_extra; | |
2138 | ||
2139 | vring_free(&vq->vq); | |
2140 | ||
2141 | virtqueue_vring_init_packed(&vring_packed, !!vq->vq.callback); | |
2142 | ||
2143 | virtqueue_init(vq, vring_packed.vring.num); | |
2144 | virtqueue_vring_attach_packed(vq, &vring_packed); | |
2145 | ||
2146 | return 0; | |
2147 | ||
2148 | err_state_extra: | |
2713ea3c | 2149 | vring_free_packed(&vring_packed, vdev, vring_dma_dev(vq)); |
947f9fcf XZ |
2150 | err_ring: |
2151 | virtqueue_reinit_packed(vq); | |
2152 | return -ENOMEM; | |
2153 | } | |
2154 | ||
ad48d53b XZ |
2155 | static int virtqueue_disable_and_recycle(struct virtqueue *_vq, |
2156 | void (*recycle)(struct virtqueue *vq, void *buf)) | |
2157 | { | |
2158 | struct vring_virtqueue *vq = to_vvq(_vq); | |
2159 | struct virtio_device *vdev = vq->vq.vdev; | |
2160 | void *buf; | |
2161 | int err; | |
2162 | ||
2163 | if (!vq->we_own_ring) | |
2164 | return -EPERM; | |
2165 | ||
2166 | if (!vdev->config->disable_vq_and_reset) | |
2167 | return -ENOENT; | |
2168 | ||
2169 | if (!vdev->config->enable_vq_after_reset) | |
2170 | return -ENOENT; | |
2171 | ||
2172 | err = vdev->config->disable_vq_and_reset(_vq); | |
2173 | if (err) | |
2174 | return err; | |
2175 | ||
2176 | while ((buf = virtqueue_detach_unused_buf(_vq)) != NULL) | |
2177 | recycle(_vq, buf); | |
2178 | ||
2179 | return 0; | |
2180 | } | |
2181 | ||
2182 | static int virtqueue_enable_after_reset(struct virtqueue *_vq) | |
2183 | { | |
2184 | struct vring_virtqueue *vq = to_vvq(_vq); | |
2185 | struct virtio_device *vdev = vq->vq.vdev; | |
2186 | ||
2187 | if (vdev->config->enable_vq_after_reset(_vq)) | |
2188 | return -EBUSY; | |
2189 | ||
2190 | return 0; | |
2191 | } | |
1ce9e605 | 2192 | |
e6f633e5 TB |
2193 | /* |
2194 | * Generic functions and exported symbols. | |
2195 | */ | |
2196 | ||
2197 | static inline int virtqueue_add(struct virtqueue *_vq, | |
2198 | struct scatterlist *sgs[], | |
2199 | unsigned int total_sg, | |
2200 | unsigned int out_sgs, | |
2201 | unsigned int in_sgs, | |
2202 | void *data, | |
2203 | void *ctx, | |
2204 | gfp_t gfp) | |
2205 | { | |
1ce9e605 TB |
2206 | struct vring_virtqueue *vq = to_vvq(_vq); |
2207 | ||
2208 | return vq->packed_ring ? virtqueue_add_packed(_vq, sgs, total_sg, | |
2209 | out_sgs, in_sgs, data, ctx, gfp) : | |
2210 | virtqueue_add_split(_vq, sgs, total_sg, | |
2211 | out_sgs, in_sgs, data, ctx, gfp); | |
e6f633e5 TB |
2212 | } |
2213 | ||
2214 | /** | |
2215 | * virtqueue_add_sgs - expose buffers to other end | |
a5581206 | 2216 | * @_vq: the struct virtqueue we're talking about. |
e6f633e5 | 2217 | * @sgs: array of terminated scatterlists. |
a5581206 JB |
2218 | * @out_sgs: the number of scatterlists readable by other side |
2219 | * @in_sgs: the number of scatterlists which are writable (after readable ones) | |
e6f633e5 TB |
2220 | * @data: the token identifying the buffer. |
2221 | * @gfp: how to do memory allocations (if necessary). | |
2222 | * | |
2223 | * Caller must ensure we don't call this with other virtqueue operations | |
2224 | * at the same time (except where noted). | |
2225 | * | |
2226 | * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). | |
2227 | */ | |
2228 | int virtqueue_add_sgs(struct virtqueue *_vq, | |
2229 | struct scatterlist *sgs[], | |
2230 | unsigned int out_sgs, | |
2231 | unsigned int in_sgs, | |
2232 | void *data, | |
2233 | gfp_t gfp) | |
2234 | { | |
2235 | unsigned int i, total_sg = 0; | |
2236 | ||
2237 | /* Count them first. */ | |
2238 | for (i = 0; i < out_sgs + in_sgs; i++) { | |
2239 | struct scatterlist *sg; | |
2240 | ||
2241 | for (sg = sgs[i]; sg; sg = sg_next(sg)) | |
2242 | total_sg++; | |
2243 | } | |
2244 | return virtqueue_add(_vq, sgs, total_sg, out_sgs, in_sgs, | |
2245 | data, NULL, gfp); | |
2246 | } | |
2247 | EXPORT_SYMBOL_GPL(virtqueue_add_sgs); | |
2248 | ||
2249 | /** | |
2250 | * virtqueue_add_outbuf - expose output buffers to other end | |
2251 | * @vq: the struct virtqueue we're talking about. | |
2252 | * @sg: scatterlist (must be well-formed and terminated!) | |
2253 | * @num: the number of entries in @sg readable by other side | |
2254 | * @data: the token identifying the buffer. | |
2255 | * @gfp: how to do memory allocations (if necessary). | |
2256 | * | |
2257 | * Caller must ensure we don't call this with other virtqueue operations | |
2258 | * at the same time (except where noted). | |
2259 | * | |
2260 | * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). | |
2261 | */ | |
2262 | int virtqueue_add_outbuf(struct virtqueue *vq, | |
2263 | struct scatterlist *sg, unsigned int num, | |
2264 | void *data, | |
2265 | gfp_t gfp) | |
2266 | { | |
2267 | return virtqueue_add(vq, &sg, num, 1, 0, data, NULL, gfp); | |
2268 | } | |
2269 | EXPORT_SYMBOL_GPL(virtqueue_add_outbuf); | |
2270 | ||
2271 | /** | |
2272 | * virtqueue_add_inbuf - expose input buffers to other end | |
2273 | * @vq: the struct virtqueue we're talking about. | |
2274 | * @sg: scatterlist (must be well-formed and terminated!) | |
2275 | * @num: the number of entries in @sg writable by other side | |
2276 | * @data: the token identifying the buffer. | |
2277 | * @gfp: how to do memory allocations (if necessary). | |
2278 | * | |
2279 | * Caller must ensure we don't call this with other virtqueue operations | |
2280 | * at the same time (except where noted). | |
2281 | * | |
2282 | * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). | |
2283 | */ | |
2284 | int virtqueue_add_inbuf(struct virtqueue *vq, | |
2285 | struct scatterlist *sg, unsigned int num, | |
2286 | void *data, | |
2287 | gfp_t gfp) | |
2288 | { | |
2289 | return virtqueue_add(vq, &sg, num, 0, 1, data, NULL, gfp); | |
2290 | } | |
2291 | EXPORT_SYMBOL_GPL(virtqueue_add_inbuf); | |
2292 | ||
2293 | /** | |
2294 | * virtqueue_add_inbuf_ctx - expose input buffers to other end | |
2295 | * @vq: the struct virtqueue we're talking about. | |
2296 | * @sg: scatterlist (must be well-formed and terminated!) | |
2297 | * @num: the number of entries in @sg writable by other side | |
2298 | * @data: the token identifying the buffer. | |
2299 | * @ctx: extra context for the token | |
2300 | * @gfp: how to do memory allocations (if necessary). | |
2301 | * | |
2302 | * Caller must ensure we don't call this with other virtqueue operations | |
2303 | * at the same time (except where noted). | |
2304 | * | |
2305 | * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). | |
2306 | */ | |
2307 | int virtqueue_add_inbuf_ctx(struct virtqueue *vq, | |
2308 | struct scatterlist *sg, unsigned int num, | |
2309 | void *data, | |
2310 | void *ctx, | |
2311 | gfp_t gfp) | |
2312 | { | |
2313 | return virtqueue_add(vq, &sg, num, 0, 1, data, ctx, gfp); | |
2314 | } | |
2315 | EXPORT_SYMBOL_GPL(virtqueue_add_inbuf_ctx); | |
2316 | ||
2df64759 XZ |
2317 | /** |
2318 | * virtqueue_dma_dev - get the dma dev | |
2319 | * @_vq: the struct virtqueue we're talking about. | |
2320 | * | |
2321 | * Returns the dma dev. That can been used for dma api. | |
2322 | */ | |
2323 | struct device *virtqueue_dma_dev(struct virtqueue *_vq) | |
2324 | { | |
2325 | struct vring_virtqueue *vq = to_vvq(_vq); | |
2326 | ||
2327 | if (vq->use_dma_api) | |
2328 | return vring_dma_dev(vq); | |
2329 | else | |
2330 | return NULL; | |
2331 | } | |
2332 | EXPORT_SYMBOL_GPL(virtqueue_dma_dev); | |
2333 | ||
e6f633e5 TB |
2334 | /** |
2335 | * virtqueue_kick_prepare - first half of split virtqueue_kick call. | |
a5581206 | 2336 | * @_vq: the struct virtqueue |
e6f633e5 TB |
2337 | * |
2338 | * Instead of virtqueue_kick(), you can do: | |
2339 | * if (virtqueue_kick_prepare(vq)) | |
2340 | * virtqueue_notify(vq); | |
2341 | * | |
2342 | * This is sometimes useful because the virtqueue_kick_prepare() needs | |
2343 | * to be serialized, but the actual virtqueue_notify() call does not. | |
2344 | */ | |
2345 | bool virtqueue_kick_prepare(struct virtqueue *_vq) | |
2346 | { | |
1ce9e605 TB |
2347 | struct vring_virtqueue *vq = to_vvq(_vq); |
2348 | ||
2349 | return vq->packed_ring ? virtqueue_kick_prepare_packed(_vq) : | |
2350 | virtqueue_kick_prepare_split(_vq); | |
e6f633e5 TB |
2351 | } |
2352 | EXPORT_SYMBOL_GPL(virtqueue_kick_prepare); | |
2353 | ||
2354 | /** | |
2355 | * virtqueue_notify - second half of split virtqueue_kick call. | |
a5581206 | 2356 | * @_vq: the struct virtqueue |
e6f633e5 TB |
2357 | * |
2358 | * This does not need to be serialized. | |
2359 | * | |
2360 | * Returns false if host notify failed or queue is broken, otherwise true. | |
2361 | */ | |
2362 | bool virtqueue_notify(struct virtqueue *_vq) | |
2363 | { | |
2364 | struct vring_virtqueue *vq = to_vvq(_vq); | |
2365 | ||
2366 | if (unlikely(vq->broken)) | |
2367 | return false; | |
2368 | ||
2369 | /* Prod other side to tell it about changes. */ | |
2370 | if (!vq->notify(_vq)) { | |
2371 | vq->broken = true; | |
2372 | return false; | |
2373 | } | |
2374 | return true; | |
2375 | } | |
2376 | EXPORT_SYMBOL_GPL(virtqueue_notify); | |
2377 | ||
2378 | /** | |
2379 | * virtqueue_kick - update after add_buf | |
2380 | * @vq: the struct virtqueue | |
2381 | * | |
2382 | * After one or more virtqueue_add_* calls, invoke this to kick | |
2383 | * the other side. | |
2384 | * | |
2385 | * Caller must ensure we don't call this with other virtqueue | |
2386 | * operations at the same time (except where noted). | |
2387 | * | |
2388 | * Returns false if kick failed, otherwise true. | |
2389 | */ | |
2390 | bool virtqueue_kick(struct virtqueue *vq) | |
2391 | { | |
2392 | if (virtqueue_kick_prepare(vq)) | |
2393 | return virtqueue_notify(vq); | |
2394 | return true; | |
2395 | } | |
2396 | EXPORT_SYMBOL_GPL(virtqueue_kick); | |
2397 | ||
2398 | /** | |
31c11db6 | 2399 | * virtqueue_get_buf_ctx - get the next used buffer |
a5581206 | 2400 | * @_vq: the struct virtqueue we're talking about. |
e6f633e5 | 2401 | * @len: the length written into the buffer |
a5581206 | 2402 | * @ctx: extra context for the token |
e6f633e5 TB |
2403 | * |
2404 | * If the device wrote data into the buffer, @len will be set to the | |
2405 | * amount written. This means you don't need to clear the buffer | |
2406 | * beforehand to ensure there's no data leakage in the case of short | |
2407 | * writes. | |
2408 | * | |
2409 | * Caller must ensure we don't call this with other virtqueue | |
2410 | * operations at the same time (except where noted). | |
2411 | * | |
2412 | * Returns NULL if there are no used buffers, or the "data" token | |
2413 | * handed to virtqueue_add_*(). | |
2414 | */ | |
2415 | void *virtqueue_get_buf_ctx(struct virtqueue *_vq, unsigned int *len, | |
2416 | void **ctx) | |
2417 | { | |
1ce9e605 TB |
2418 | struct vring_virtqueue *vq = to_vvq(_vq); |
2419 | ||
2420 | return vq->packed_ring ? virtqueue_get_buf_ctx_packed(_vq, len, ctx) : | |
2421 | virtqueue_get_buf_ctx_split(_vq, len, ctx); | |
e6f633e5 TB |
2422 | } |
2423 | EXPORT_SYMBOL_GPL(virtqueue_get_buf_ctx); | |
2424 | ||
2425 | void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len) | |
2426 | { | |
2427 | return virtqueue_get_buf_ctx(_vq, len, NULL); | |
2428 | } | |
2429 | EXPORT_SYMBOL_GPL(virtqueue_get_buf); | |
e6f633e5 TB |
2430 | /** |
2431 | * virtqueue_disable_cb - disable callbacks | |
a5581206 | 2432 | * @_vq: the struct virtqueue we're talking about. |
e6f633e5 TB |
2433 | * |
2434 | * Note that this is not necessarily synchronous, hence unreliable and only | |
2435 | * useful as an optimization. | |
2436 | * | |
2437 | * Unlike other operations, this need not be serialized. | |
2438 | */ | |
2439 | void virtqueue_disable_cb(struct virtqueue *_vq) | |
2440 | { | |
1ce9e605 TB |
2441 | struct vring_virtqueue *vq = to_vvq(_vq); |
2442 | ||
2443 | if (vq->packed_ring) | |
2444 | virtqueue_disable_cb_packed(_vq); | |
2445 | else | |
2446 | virtqueue_disable_cb_split(_vq); | |
e6f633e5 TB |
2447 | } |
2448 | EXPORT_SYMBOL_GPL(virtqueue_disable_cb); | |
2449 | ||
2450 | /** | |
2451 | * virtqueue_enable_cb_prepare - restart callbacks after disable_cb | |
a5581206 | 2452 | * @_vq: the struct virtqueue we're talking about. |
e6f633e5 TB |
2453 | * |
2454 | * This re-enables callbacks; it returns current queue state | |
2455 | * in an opaque unsigned value. This value should be later tested by | |
2456 | * virtqueue_poll, to detect a possible race between the driver checking for | |
2457 | * more work, and enabling callbacks. | |
2458 | * | |
2459 | * Caller must ensure we don't call this with other virtqueue | |
2460 | * operations at the same time (except where noted). | |
2461 | */ | |
31532340 | 2462 | unsigned int virtqueue_enable_cb_prepare(struct virtqueue *_vq) |
e6f633e5 | 2463 | { |
1ce9e605 TB |
2464 | struct vring_virtqueue *vq = to_vvq(_vq); |
2465 | ||
8d622d21 MT |
2466 | if (vq->event_triggered) |
2467 | vq->event_triggered = false; | |
2468 | ||
1ce9e605 TB |
2469 | return vq->packed_ring ? virtqueue_enable_cb_prepare_packed(_vq) : |
2470 | virtqueue_enable_cb_prepare_split(_vq); | |
e6f633e5 TB |
2471 | } |
2472 | EXPORT_SYMBOL_GPL(virtqueue_enable_cb_prepare); | |
2473 | ||
2474 | /** | |
2475 | * virtqueue_poll - query pending used buffers | |
a5581206 | 2476 | * @_vq: the struct virtqueue we're talking about. |
e6f633e5 TB |
2477 | * @last_used_idx: virtqueue state (from call to virtqueue_enable_cb_prepare). |
2478 | * | |
2479 | * Returns "true" if there are pending used buffers in the queue. | |
2480 | * | |
2481 | * This does not need to be serialized. | |
2482 | */ | |
31532340 | 2483 | bool virtqueue_poll(struct virtqueue *_vq, unsigned int last_used_idx) |
e6f633e5 TB |
2484 | { |
2485 | struct vring_virtqueue *vq = to_vvq(_vq); | |
2486 | ||
481a0d74 MW |
2487 | if (unlikely(vq->broken)) |
2488 | return false; | |
2489 | ||
e6f633e5 | 2490 | virtio_mb(vq->weak_barriers); |
1ce9e605 TB |
2491 | return vq->packed_ring ? virtqueue_poll_packed(_vq, last_used_idx) : |
2492 | virtqueue_poll_split(_vq, last_used_idx); | |
e6f633e5 TB |
2493 | } |
2494 | EXPORT_SYMBOL_GPL(virtqueue_poll); | |
2495 | ||
2496 | /** | |
2497 | * virtqueue_enable_cb - restart callbacks after disable_cb. | |
a5581206 | 2498 | * @_vq: the struct virtqueue we're talking about. |
e6f633e5 TB |
2499 | * |
2500 | * This re-enables callbacks; it returns "false" if there are pending | |
2501 | * buffers in the queue, to detect a possible race between the driver | |
2502 | * checking for more work, and enabling callbacks. | |
2503 | * | |
2504 | * Caller must ensure we don't call this with other virtqueue | |
2505 | * operations at the same time (except where noted). | |
2506 | */ | |
2507 | bool virtqueue_enable_cb(struct virtqueue *_vq) | |
2508 | { | |
31532340 | 2509 | unsigned int last_used_idx = virtqueue_enable_cb_prepare(_vq); |
e6f633e5 TB |
2510 | |
2511 | return !virtqueue_poll(_vq, last_used_idx); | |
2512 | } | |
2513 | EXPORT_SYMBOL_GPL(virtqueue_enable_cb); | |
2514 | ||
2515 | /** | |
2516 | * virtqueue_enable_cb_delayed - restart callbacks after disable_cb. | |
a5581206 | 2517 | * @_vq: the struct virtqueue we're talking about. |
e6f633e5 TB |
2518 | * |
2519 | * This re-enables callbacks but hints to the other side to delay | |
2520 | * interrupts until most of the available buffers have been processed; | |
2521 | * it returns "false" if there are many pending buffers in the queue, | |
2522 | * to detect a possible race between the driver checking for more work, | |
2523 | * and enabling callbacks. | |
2524 | * | |
2525 | * Caller must ensure we don't call this with other virtqueue | |
2526 | * operations at the same time (except where noted). | |
2527 | */ | |
2528 | bool virtqueue_enable_cb_delayed(struct virtqueue *_vq) | |
2529 | { | |
1ce9e605 TB |
2530 | struct vring_virtqueue *vq = to_vvq(_vq); |
2531 | ||
8d622d21 MT |
2532 | if (vq->event_triggered) |
2533 | vq->event_triggered = false; | |
2534 | ||
1ce9e605 TB |
2535 | return vq->packed_ring ? virtqueue_enable_cb_delayed_packed(_vq) : |
2536 | virtqueue_enable_cb_delayed_split(_vq); | |
e6f633e5 TB |
2537 | } |
2538 | EXPORT_SYMBOL_GPL(virtqueue_enable_cb_delayed); | |
2539 | ||
138fd251 TB |
2540 | /** |
2541 | * virtqueue_detach_unused_buf - detach first unused buffer | |
a5581206 | 2542 | * @_vq: the struct virtqueue we're talking about. |
138fd251 TB |
2543 | * |
2544 | * Returns NULL or the "data" token handed to virtqueue_add_*(). | |
a62eecb3 XZ |
2545 | * This is not valid on an active queue; it is useful for device |
2546 | * shutdown or the reset queue. | |
138fd251 TB |
2547 | */ |
2548 | void *virtqueue_detach_unused_buf(struct virtqueue *_vq) | |
2549 | { | |
1ce9e605 TB |
2550 | struct vring_virtqueue *vq = to_vvq(_vq); |
2551 | ||
2552 | return vq->packed_ring ? virtqueue_detach_unused_buf_packed(_vq) : | |
2553 | virtqueue_detach_unused_buf_split(_vq); | |
138fd251 | 2554 | } |
7c5e9ed0 | 2555 | EXPORT_SYMBOL_GPL(virtqueue_detach_unused_buf); |
c021eac4 | 2556 | |
138fd251 TB |
2557 | static inline bool more_used(const struct vring_virtqueue *vq) |
2558 | { | |
1ce9e605 | 2559 | return vq->packed_ring ? more_used_packed(vq) : more_used_split(vq); |
138fd251 TB |
2560 | } |
2561 | ||
5c669c4a RC |
2562 | /** |
2563 | * vring_interrupt - notify a virtqueue on an interrupt | |
2564 | * @irq: the IRQ number (ignored) | |
2565 | * @_vq: the struct virtqueue to notify | |
2566 | * | |
2567 | * Calls the callback function of @_vq to process the virtqueue | |
2568 | * notification. | |
2569 | */ | |
0a8a69dd RR |
2570 | irqreturn_t vring_interrupt(int irq, void *_vq) |
2571 | { | |
2572 | struct vring_virtqueue *vq = to_vvq(_vq); | |
2573 | ||
2574 | if (!more_used(vq)) { | |
2575 | pr_debug("virtqueue interrupt with no work for %p\n", vq); | |
2576 | return IRQ_NONE; | |
2577 | } | |
2578 | ||
8b4ec69d | 2579 | if (unlikely(vq->broken)) { |
c346dae4 | 2580 | #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION |
8b4ec69d JW |
2581 | dev_warn_once(&vq->vq.vdev->dev, |
2582 | "virtio vring IRQ raised before DRIVER_OK"); | |
2583 | return IRQ_NONE; | |
c346dae4 JW |
2584 | #else |
2585 | return IRQ_HANDLED; | |
2586 | #endif | |
8b4ec69d | 2587 | } |
0a8a69dd | 2588 | |
8d622d21 MT |
2589 | /* Just a hint for performance: so it's ok that this can be racy! */ |
2590 | if (vq->event) | |
2591 | vq->event_triggered = true; | |
2592 | ||
0a8a69dd | 2593 | pr_debug("virtqueue callback for %p (%p)\n", vq, vq->vq.callback); |
18445c4d RR |
2594 | if (vq->vq.callback) |
2595 | vq->vq.callback(&vq->vq); | |
0a8a69dd RR |
2596 | |
2597 | return IRQ_HANDLED; | |
2598 | } | |
c6fd4701 | 2599 | EXPORT_SYMBOL_GPL(vring_interrupt); |
0a8a69dd | 2600 | |
1ce9e605 | 2601 | /* Only available for split ring */ |
07d9629d | 2602 | static struct virtqueue *__vring_new_virtqueue(unsigned int index, |
cd4c812a | 2603 | struct vring_virtqueue_split *vring_split, |
07d9629d XZ |
2604 | struct virtio_device *vdev, |
2605 | bool weak_barriers, | |
2606 | bool context, | |
2607 | bool (*notify)(struct virtqueue *), | |
2608 | void (*callback)(struct virtqueue *), | |
2713ea3c JW |
2609 | const char *name, |
2610 | struct device *dma_dev) | |
0a8a69dd | 2611 | { |
2a2d1382 | 2612 | struct vring_virtqueue *vq; |
a2b36c8d | 2613 | int err; |
0a8a69dd | 2614 | |
1ce9e605 TB |
2615 | if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) |
2616 | return NULL; | |
2617 | ||
cbeedb72 | 2618 | vq = kmalloc(sizeof(*vq), GFP_KERNEL); |
0a8a69dd RR |
2619 | if (!vq) |
2620 | return NULL; | |
2621 | ||
1ce9e605 | 2622 | vq->packed_ring = false; |
0a8a69dd RR |
2623 | vq->vq.callback = callback; |
2624 | vq->vq.vdev = vdev; | |
9499f5e7 | 2625 | vq->vq.name = name; |
06ca287d | 2626 | vq->vq.index = index; |
4913e854 | 2627 | vq->vq.reset = false; |
2a2d1382 | 2628 | vq->we_own_ring = false; |
0a8a69dd | 2629 | vq->notify = notify; |
7b21e34f | 2630 | vq->weak_barriers = weak_barriers; |
c346dae4 | 2631 | #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION |
8b4ec69d | 2632 | vq->broken = true; |
c346dae4 JW |
2633 | #else |
2634 | vq->broken = false; | |
2635 | #endif | |
2713ea3c | 2636 | vq->dma_dev = dma_dev; |
fb3fba6b | 2637 | vq->use_dma_api = vring_use_dma_api(vdev); |
8daafe9e | 2638 | vq->premapped = false; |
b319940f | 2639 | vq->do_unmap = vq->use_dma_api; |
0a8a69dd | 2640 | |
5a08b04f MT |
2641 | vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) && |
2642 | !context; | |
a5c262c5 | 2643 | vq->event = virtio_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX); |
9fa29b9d | 2644 | |
45383fb0 TB |
2645 | if (virtio_has_feature(vdev, VIRTIO_F_ORDER_PLATFORM)) |
2646 | vq->weak_barriers = false; | |
2647 | ||
a2b36c8d XZ |
2648 | err = vring_alloc_state_extra_split(vring_split); |
2649 | if (err) { | |
2650 | kfree(vq); | |
2651 | return NULL; | |
2652 | } | |
72b5e895 | 2653 | |
198fa7be XZ |
2654 | virtqueue_vring_init_split(vring_split, vq); |
2655 | ||
cd4c812a | 2656 | virtqueue_init(vq, vring_split->vring.num); |
e1d6a423 | 2657 | virtqueue_vring_attach_split(vq, vring_split); |
3a897128 | 2658 | |
0e566c8f | 2659 | spin_lock(&vdev->vqs_list_lock); |
e152d8af | 2660 | list_add_tail(&vq->vq.list, &vdev->vqs); |
0e566c8f | 2661 | spin_unlock(&vdev->vqs_list_lock); |
0a8a69dd RR |
2662 | return &vq->vq; |
2663 | } | |
2a2d1382 | 2664 | |
2a2d1382 AL |
2665 | struct virtqueue *vring_create_virtqueue( |
2666 | unsigned int index, | |
2667 | unsigned int num, | |
2668 | unsigned int vring_align, | |
2669 | struct virtio_device *vdev, | |
2670 | bool weak_barriers, | |
2671 | bool may_reduce_num, | |
f94682dd | 2672 | bool context, |
2a2d1382 AL |
2673 | bool (*notify)(struct virtqueue *), |
2674 | void (*callback)(struct virtqueue *), | |
2675 | const char *name) | |
2676 | { | |
1ce9e605 TB |
2677 | |
2678 | if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) | |
2679 | return vring_create_virtqueue_packed(index, num, vring_align, | |
2680 | vdev, weak_barriers, may_reduce_num, | |
2713ea3c | 2681 | context, notify, callback, name, vdev->dev.parent); |
1ce9e605 | 2682 | |
d79dca75 TB |
2683 | return vring_create_virtqueue_split(index, num, vring_align, |
2684 | vdev, weak_barriers, may_reduce_num, | |
2713ea3c | 2685 | context, notify, callback, name, vdev->dev.parent); |
2a2d1382 AL |
2686 | } |
2687 | EXPORT_SYMBOL_GPL(vring_create_virtqueue); | |
2688 | ||
2713ea3c JW |
2689 | struct virtqueue *vring_create_virtqueue_dma( |
2690 | unsigned int index, | |
2691 | unsigned int num, | |
2692 | unsigned int vring_align, | |
2693 | struct virtio_device *vdev, | |
2694 | bool weak_barriers, | |
2695 | bool may_reduce_num, | |
2696 | bool context, | |
2697 | bool (*notify)(struct virtqueue *), | |
2698 | void (*callback)(struct virtqueue *), | |
2699 | const char *name, | |
2700 | struct device *dma_dev) | |
2701 | { | |
2702 | ||
2703 | if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) | |
2704 | return vring_create_virtqueue_packed(index, num, vring_align, | |
2705 | vdev, weak_barriers, may_reduce_num, | |
2706 | context, notify, callback, name, dma_dev); | |
2707 | ||
2708 | return vring_create_virtqueue_split(index, num, vring_align, | |
2709 | vdev, weak_barriers, may_reduce_num, | |
2710 | context, notify, callback, name, dma_dev); | |
2711 | } | |
2712 | EXPORT_SYMBOL_GPL(vring_create_virtqueue_dma); | |
2713 | ||
c790e8e1 XZ |
2714 | /** |
2715 | * virtqueue_resize - resize the vring of vq | |
2716 | * @_vq: the struct virtqueue we're talking about. | |
2717 | * @num: new ring num | |
4d09f240 | 2718 | * @recycle: callback to recycle unused buffers |
c790e8e1 XZ |
2719 | * |
2720 | * When it is really necessary to create a new vring, it will set the current vq | |
2721 | * into the reset state. Then call the passed callback to recycle the buffer | |
2722 | * that is no longer used. Only after the new vring is successfully created, the | |
2723 | * old vring will be released. | |
2724 | * | |
2725 | * Caller must ensure we don't call this with other virtqueue operations | |
2726 | * at the same time (except where noted). | |
2727 | * | |
2728 | * Returns zero or a negative error. | |
2729 | * 0: success. | |
2730 | * -ENOMEM: Failed to allocate a new ring, fall back to the original ring size. | |
2731 | * vq can still work normally | |
2732 | * -EBUSY: Failed to sync with device, vq may not work properly | |
2733 | * -ENOENT: Transport or device not supported | |
2734 | * -E2BIG/-EINVAL: num error | |
2735 | * -EPERM: Operation not permitted | |
2736 | * | |
2737 | */ | |
2738 | int virtqueue_resize(struct virtqueue *_vq, u32 num, | |
2739 | void (*recycle)(struct virtqueue *vq, void *buf)) | |
2740 | { | |
2741 | struct vring_virtqueue *vq = to_vvq(_vq); | |
c790e8e1 XZ |
2742 | int err; |
2743 | ||
c790e8e1 XZ |
2744 | if (num > vq->vq.num_max) |
2745 | return -E2BIG; | |
2746 | ||
2747 | if (!num) | |
2748 | return -EINVAL; | |
2749 | ||
2750 | if ((vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num) == num) | |
2751 | return 0; | |
2752 | ||
ad48d53b | 2753 | err = virtqueue_disable_and_recycle(_vq, recycle); |
c790e8e1 XZ |
2754 | if (err) |
2755 | return err; | |
2756 | ||
c790e8e1 XZ |
2757 | if (vq->packed_ring) |
2758 | err = virtqueue_resize_packed(_vq, num); | |
2759 | else | |
2760 | err = virtqueue_resize_split(_vq, num); | |
2761 | ||
ad48d53b | 2762 | return virtqueue_enable_after_reset(_vq); |
c790e8e1 XZ |
2763 | } |
2764 | EXPORT_SYMBOL_GPL(virtqueue_resize); | |
2765 | ||
8daafe9e XZ |
2766 | /** |
2767 | * virtqueue_set_dma_premapped - set the vring premapped mode | |
2768 | * @_vq: the struct virtqueue we're talking about. | |
2769 | * | |
2770 | * Enable the premapped mode of the vq. | |
2771 | * | |
2772 | * The vring in premapped mode does not do dma internally, so the driver must | |
2773 | * do dma mapping in advance. The driver must pass the dma_address through | |
2774 | * dma_address of scatterlist. When the driver got a used buffer from | |
2775 | * the vring, it has to unmap the dma address. | |
2776 | * | |
2777 | * This function must be called immediately after creating the vq, or after vq | |
2778 | * reset, and before adding any buffers to it. | |
2779 | * | |
2780 | * Caller must ensure we don't call this with other virtqueue operations | |
2781 | * at the same time (except where noted). | |
2782 | * | |
2783 | * Returns zero or a negative error. | |
2784 | * 0: success. | |
2785 | * -EINVAL: vring does not use the dma api, so we can not enable premapped mode. | |
2786 | */ | |
2787 | int virtqueue_set_dma_premapped(struct virtqueue *_vq) | |
2788 | { | |
2789 | struct vring_virtqueue *vq = to_vvq(_vq); | |
2790 | u32 num; | |
2791 | ||
2792 | START_USE(vq); | |
2793 | ||
2794 | num = vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num; | |
2795 | ||
2796 | if (num != vq->vq.num_free) { | |
2797 | END_USE(vq); | |
2798 | return -EINVAL; | |
2799 | } | |
2800 | ||
2801 | if (!vq->use_dma_api) { | |
2802 | END_USE(vq); | |
2803 | return -EINVAL; | |
2804 | } | |
2805 | ||
2806 | vq->premapped = true; | |
b319940f | 2807 | vq->do_unmap = false; |
8daafe9e XZ |
2808 | |
2809 | END_USE(vq); | |
2810 | ||
2811 | return 0; | |
2812 | } | |
2813 | EXPORT_SYMBOL_GPL(virtqueue_set_dma_premapped); | |
2814 | ||
ba3e0c47 XZ |
2815 | /** |
2816 | * virtqueue_reset - detach and recycle all unused buffers | |
2817 | * @_vq: the struct virtqueue we're talking about. | |
2818 | * @recycle: callback to recycle unused buffers | |
2819 | * | |
2820 | * Caller must ensure we don't call this with other virtqueue operations | |
2821 | * at the same time (except where noted). | |
2822 | * | |
2823 | * Returns zero or a negative error. | |
2824 | * 0: success. | |
2825 | * -EBUSY: Failed to sync with device, vq may not work properly | |
2826 | * -ENOENT: Transport or device not supported | |
2827 | * -EPERM: Operation not permitted | |
2828 | */ | |
2829 | int virtqueue_reset(struct virtqueue *_vq, | |
2830 | void (*recycle)(struct virtqueue *vq, void *buf)) | |
2831 | { | |
2832 | struct vring_virtqueue *vq = to_vvq(_vq); | |
2833 | int err; | |
2834 | ||
2835 | err = virtqueue_disable_and_recycle(_vq, recycle); | |
2836 | if (err) | |
2837 | return err; | |
2838 | ||
2839 | if (vq->packed_ring) | |
2840 | virtqueue_reinit_packed(vq); | |
2841 | else | |
2842 | virtqueue_reinit_split(vq); | |
2843 | ||
2844 | return virtqueue_enable_after_reset(_vq); | |
2845 | } | |
2846 | EXPORT_SYMBOL_GPL(virtqueue_reset); | |
2847 | ||
1ce9e605 | 2848 | /* Only available for split ring */ |
2a2d1382 AL |
2849 | struct virtqueue *vring_new_virtqueue(unsigned int index, |
2850 | unsigned int num, | |
2851 | unsigned int vring_align, | |
2852 | struct virtio_device *vdev, | |
2853 | bool weak_barriers, | |
f94682dd | 2854 | bool context, |
2a2d1382 AL |
2855 | void *pages, |
2856 | bool (*notify)(struct virtqueue *vq), | |
2857 | void (*callback)(struct virtqueue *vq), | |
2858 | const char *name) | |
2859 | { | |
cd4c812a | 2860 | struct vring_virtqueue_split vring_split = {}; |
1ce9e605 TB |
2861 | |
2862 | if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) | |
2863 | return NULL; | |
2864 | ||
cd4c812a XZ |
2865 | vring_init(&vring_split.vring, num, pages, vring_align); |
2866 | return __vring_new_virtqueue(index, &vring_split, vdev, weak_barriers, | |
2713ea3c JW |
2867 | context, notify, callback, name, |
2868 | vdev->dev.parent); | |
2a2d1382 | 2869 | } |
c6fd4701 | 2870 | EXPORT_SYMBOL_GPL(vring_new_virtqueue); |
0a8a69dd | 2871 | |
3ea19e32 | 2872 | static void vring_free(struct virtqueue *_vq) |
0a8a69dd | 2873 | { |
2a2d1382 AL |
2874 | struct vring_virtqueue *vq = to_vvq(_vq); |
2875 | ||
2876 | if (vq->we_own_ring) { | |
1ce9e605 TB |
2877 | if (vq->packed_ring) { |
2878 | vring_free_queue(vq->vq.vdev, | |
2879 | vq->packed.ring_size_in_bytes, | |
2880 | vq->packed.vring.desc, | |
2713ea3c JW |
2881 | vq->packed.ring_dma_addr, |
2882 | vring_dma_dev(vq)); | |
1ce9e605 TB |
2883 | |
2884 | vring_free_queue(vq->vq.vdev, | |
2885 | vq->packed.event_size_in_bytes, | |
2886 | vq->packed.vring.driver, | |
2713ea3c JW |
2887 | vq->packed.driver_event_dma_addr, |
2888 | vring_dma_dev(vq)); | |
1ce9e605 TB |
2889 | |
2890 | vring_free_queue(vq->vq.vdev, | |
2891 | vq->packed.event_size_in_bytes, | |
2892 | vq->packed.vring.device, | |
2713ea3c JW |
2893 | vq->packed.device_event_dma_addr, |
2894 | vring_dma_dev(vq)); | |
1ce9e605 TB |
2895 | |
2896 | kfree(vq->packed.desc_state); | |
2897 | kfree(vq->packed.desc_extra); | |
2898 | } else { | |
2899 | vring_free_queue(vq->vq.vdev, | |
2900 | vq->split.queue_size_in_bytes, | |
2901 | vq->split.vring.desc, | |
2713ea3c JW |
2902 | vq->split.queue_dma_addr, |
2903 | vring_dma_dev(vq)); | |
1ce9e605 | 2904 | } |
2a2d1382 | 2905 | } |
72b5e895 | 2906 | if (!vq->packed_ring) { |
f13f09a1 | 2907 | kfree(vq->split.desc_state); |
72b5e895 JW |
2908 | kfree(vq->split.desc_extra); |
2909 | } | |
3ea19e32 XZ |
2910 | } |
2911 | ||
2912 | void vring_del_virtqueue(struct virtqueue *_vq) | |
2913 | { | |
2914 | struct vring_virtqueue *vq = to_vvq(_vq); | |
2915 | ||
2916 | spin_lock(&vq->vq.vdev->vqs_list_lock); | |
2917 | list_del(&_vq->list); | |
2918 | spin_unlock(&vq->vq.vdev->vqs_list_lock); | |
2919 | ||
2920 | vring_free(_vq); | |
2921 | ||
2a2d1382 | 2922 | kfree(vq); |
0a8a69dd | 2923 | } |
c6fd4701 | 2924 | EXPORT_SYMBOL_GPL(vring_del_virtqueue); |
0a8a69dd | 2925 | |
af8ececd VP |
2926 | u32 vring_notification_data(struct virtqueue *_vq) |
2927 | { | |
2928 | struct vring_virtqueue *vq = to_vvq(_vq); | |
2929 | u16 next; | |
2930 | ||
2931 | if (vq->packed_ring) | |
2932 | next = (vq->packed.next_avail_idx & | |
2933 | ~(-(1 << VRING_PACKED_EVENT_F_WRAP_CTR))) | | |
2934 | vq->packed.avail_wrap_counter << | |
2935 | VRING_PACKED_EVENT_F_WRAP_CTR; | |
2936 | else | |
2937 | next = vq->split.avail_idx_shadow; | |
2938 | ||
2939 | return next << 16 | _vq->index; | |
2940 | } | |
2941 | EXPORT_SYMBOL_GPL(vring_notification_data); | |
2942 | ||
e34f8725 RR |
2943 | /* Manipulates transport-specific feature bits. */ |
2944 | void vring_transport_features(struct virtio_device *vdev) | |
2945 | { | |
2946 | unsigned int i; | |
2947 | ||
2948 | for (i = VIRTIO_TRANSPORT_F_START; i < VIRTIO_TRANSPORT_F_END; i++) { | |
2949 | switch (i) { | |
9fa29b9d MM |
2950 | case VIRTIO_RING_F_INDIRECT_DESC: |
2951 | break; | |
a5c262c5 MT |
2952 | case VIRTIO_RING_F_EVENT_IDX: |
2953 | break; | |
747ae34a MT |
2954 | case VIRTIO_F_VERSION_1: |
2955 | break; | |
321bd212 | 2956 | case VIRTIO_F_ACCESS_PLATFORM: |
1a937693 | 2957 | break; |
f959a128 TB |
2958 | case VIRTIO_F_RING_PACKED: |
2959 | break; | |
45383fb0 TB |
2960 | case VIRTIO_F_ORDER_PLATFORM: |
2961 | break; | |
af8ececd VP |
2962 | case VIRTIO_F_NOTIFICATION_DATA: |
2963 | break; | |
e34f8725 RR |
2964 | default: |
2965 | /* We don't understand this bit. */ | |
e16e12be | 2966 | __virtio_clear_bit(vdev, i); |
e34f8725 RR |
2967 | } |
2968 | } | |
2969 | } | |
2970 | EXPORT_SYMBOL_GPL(vring_transport_features); | |
2971 | ||
5dfc1762 RR |
2972 | /** |
2973 | * virtqueue_get_vring_size - return the size of the virtqueue's vring | |
a5581206 | 2974 | * @_vq: the struct virtqueue containing the vring of interest. |
5dfc1762 RR |
2975 | * |
2976 | * Returns the size of the vring. This is mainly used for boasting to | |
2977 | * userspace. Unlike other operations, this need not be serialized. | |
2978 | */ | |
4b6ec919 | 2979 | unsigned int virtqueue_get_vring_size(const struct virtqueue *_vq) |
8f9f4668 RJ |
2980 | { |
2981 | ||
4b6ec919 | 2982 | const struct vring_virtqueue *vq = to_vvq(_vq); |
8f9f4668 | 2983 | |
1ce9e605 | 2984 | return vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num; |
8f9f4668 RJ |
2985 | } |
2986 | EXPORT_SYMBOL_GPL(virtqueue_get_vring_size); | |
2987 | ||
32510631 XZ |
2988 | /* |
2989 | * This function should only be called by the core, not directly by the driver. | |
2990 | */ | |
2991 | void __virtqueue_break(struct virtqueue *_vq) | |
2992 | { | |
2993 | struct vring_virtqueue *vq = to_vvq(_vq); | |
2994 | ||
2995 | /* Pairs with READ_ONCE() in virtqueue_is_broken(). */ | |
2996 | WRITE_ONCE(vq->broken, true); | |
2997 | } | |
2998 | EXPORT_SYMBOL_GPL(__virtqueue_break); | |
2999 | ||
3000 | /* | |
3001 | * This function should only be called by the core, not directly by the driver. | |
3002 | */ | |
3003 | void __virtqueue_unbreak(struct virtqueue *_vq) | |
3004 | { | |
3005 | struct vring_virtqueue *vq = to_vvq(_vq); | |
3006 | ||
3007 | /* Pairs with READ_ONCE() in virtqueue_is_broken(). */ | |
3008 | WRITE_ONCE(vq->broken, false); | |
3009 | } | |
3010 | EXPORT_SYMBOL_GPL(__virtqueue_unbreak); | |
3011 | ||
4b6ec919 | 3012 | bool virtqueue_is_broken(const struct virtqueue *_vq) |
b3b32c94 | 3013 | { |
4b6ec919 | 3014 | const struct vring_virtqueue *vq = to_vvq(_vq); |
b3b32c94 | 3015 | |
60f07798 | 3016 | return READ_ONCE(vq->broken); |
b3b32c94 HG |
3017 | } |
3018 | EXPORT_SYMBOL_GPL(virtqueue_is_broken); | |
3019 | ||
e2dcdfe9 RR |
3020 | /* |
3021 | * This should prevent the device from being used, allowing drivers to | |
3022 | * recover. You may need to grab appropriate locks to flush. | |
3023 | */ | |
3024 | void virtio_break_device(struct virtio_device *dev) | |
3025 | { | |
3026 | struct virtqueue *_vq; | |
3027 | ||
0e566c8f | 3028 | spin_lock(&dev->vqs_list_lock); |
e2dcdfe9 RR |
3029 | list_for_each_entry(_vq, &dev->vqs, list) { |
3030 | struct vring_virtqueue *vq = to_vvq(_vq); | |
60f07798 PP |
3031 | |
3032 | /* Pairs with READ_ONCE() in virtqueue_is_broken(). */ | |
3033 | WRITE_ONCE(vq->broken, true); | |
e2dcdfe9 | 3034 | } |
0e566c8f | 3035 | spin_unlock(&dev->vqs_list_lock); |
e2dcdfe9 RR |
3036 | } |
3037 | EXPORT_SYMBOL_GPL(virtio_break_device); | |
3038 | ||
be83f04d JW |
3039 | /* |
3040 | * This should allow the device to be used by the driver. You may | |
3041 | * need to grab appropriate locks to flush the write to | |
3042 | * vq->broken. This should only be used in some specific case e.g | |
3043 | * (probing and restoring). This function should only be called by the | |
3044 | * core, not directly by the driver. | |
3045 | */ | |
3046 | void __virtio_unbreak_device(struct virtio_device *dev) | |
3047 | { | |
3048 | struct virtqueue *_vq; | |
3049 | ||
3050 | spin_lock(&dev->vqs_list_lock); | |
3051 | list_for_each_entry(_vq, &dev->vqs, list) { | |
3052 | struct vring_virtqueue *vq = to_vvq(_vq); | |
3053 | ||
3054 | /* Pairs with READ_ONCE() in virtqueue_is_broken(). */ | |
3055 | WRITE_ONCE(vq->broken, false); | |
3056 | } | |
3057 | spin_unlock(&dev->vqs_list_lock); | |
3058 | } | |
3059 | EXPORT_SYMBOL_GPL(__virtio_unbreak_device); | |
3060 | ||
4b6ec919 | 3061 | dma_addr_t virtqueue_get_desc_addr(const struct virtqueue *_vq) |
89062652 | 3062 | { |
4b6ec919 | 3063 | const struct vring_virtqueue *vq = to_vvq(_vq); |
89062652 | 3064 | |
2a2d1382 AL |
3065 | BUG_ON(!vq->we_own_ring); |
3066 | ||
1ce9e605 TB |
3067 | if (vq->packed_ring) |
3068 | return vq->packed.ring_dma_addr; | |
3069 | ||
d79dca75 | 3070 | return vq->split.queue_dma_addr; |
89062652 | 3071 | } |
2a2d1382 | 3072 | EXPORT_SYMBOL_GPL(virtqueue_get_desc_addr); |
89062652 | 3073 | |
4b6ec919 | 3074 | dma_addr_t virtqueue_get_avail_addr(const struct virtqueue *_vq) |
89062652 | 3075 | { |
4b6ec919 | 3076 | const struct vring_virtqueue *vq = to_vvq(_vq); |
89062652 | 3077 | |
2a2d1382 AL |
3078 | BUG_ON(!vq->we_own_ring); |
3079 | ||
1ce9e605 TB |
3080 | if (vq->packed_ring) |
3081 | return vq->packed.driver_event_dma_addr; | |
3082 | ||
d79dca75 | 3083 | return vq->split.queue_dma_addr + |
e593bf97 | 3084 | ((char *)vq->split.vring.avail - (char *)vq->split.vring.desc); |
2a2d1382 AL |
3085 | } |
3086 | EXPORT_SYMBOL_GPL(virtqueue_get_avail_addr); | |
3087 | ||
4b6ec919 | 3088 | dma_addr_t virtqueue_get_used_addr(const struct virtqueue *_vq) |
2a2d1382 | 3089 | { |
4b6ec919 | 3090 | const struct vring_virtqueue *vq = to_vvq(_vq); |
2a2d1382 AL |
3091 | |
3092 | BUG_ON(!vq->we_own_ring); | |
3093 | ||
1ce9e605 TB |
3094 | if (vq->packed_ring) |
3095 | return vq->packed.device_event_dma_addr; | |
3096 | ||
d79dca75 | 3097 | return vq->split.queue_dma_addr + |
e593bf97 | 3098 | ((char *)vq->split.vring.used - (char *)vq->split.vring.desc); |
2a2d1382 AL |
3099 | } |
3100 | EXPORT_SYMBOL_GPL(virtqueue_get_used_addr); | |
3101 | ||
1ce9e605 | 3102 | /* Only available for split ring */ |
4b6ec919 | 3103 | const struct vring *virtqueue_get_vring(const struct virtqueue *vq) |
2a2d1382 | 3104 | { |
e593bf97 | 3105 | return &to_vvq(vq)->split.vring; |
89062652 | 3106 | } |
2a2d1382 | 3107 | EXPORT_SYMBOL_GPL(virtqueue_get_vring); |
89062652 | 3108 | |
b6253b4e XZ |
3109 | /** |
3110 | * virtqueue_dma_map_single_attrs - map DMA for _vq | |
3111 | * @_vq: the struct virtqueue we're talking about. | |
3112 | * @ptr: the pointer of the buffer to do dma | |
3113 | * @size: the size of the buffer to do dma | |
3114 | * @dir: DMA direction | |
3115 | * @attrs: DMA Attrs | |
3116 | * | |
3117 | * The caller calls this to do dma mapping in advance. The DMA address can be | |
3118 | * passed to this _vq when it is in pre-mapped mode. | |
3119 | * | |
3120 | * return DMA address. Caller should check that by virtqueue_dma_mapping_error(). | |
3121 | */ | |
3122 | dma_addr_t virtqueue_dma_map_single_attrs(struct virtqueue *_vq, void *ptr, | |
3123 | size_t size, | |
3124 | enum dma_data_direction dir, | |
3125 | unsigned long attrs) | |
3126 | { | |
3127 | struct vring_virtqueue *vq = to_vvq(_vq); | |
3128 | ||
3129 | if (!vq->use_dma_api) | |
3130 | return (dma_addr_t)virt_to_phys(ptr); | |
3131 | ||
3132 | return dma_map_single_attrs(vring_dma_dev(vq), ptr, size, dir, attrs); | |
3133 | } | |
3134 | EXPORT_SYMBOL_GPL(virtqueue_dma_map_single_attrs); | |
3135 | ||
3136 | /** | |
3137 | * virtqueue_dma_unmap_single_attrs - unmap DMA for _vq | |
3138 | * @_vq: the struct virtqueue we're talking about. | |
3139 | * @addr: the dma address to unmap | |
3140 | * @size: the size of the buffer | |
3141 | * @dir: DMA direction | |
3142 | * @attrs: DMA Attrs | |
3143 | * | |
3144 | * Unmap the address that is mapped by the virtqueue_dma_map_* APIs. | |
3145 | * | |
3146 | */ | |
3147 | void virtqueue_dma_unmap_single_attrs(struct virtqueue *_vq, dma_addr_t addr, | |
3148 | size_t size, enum dma_data_direction dir, | |
3149 | unsigned long attrs) | |
3150 | { | |
3151 | struct vring_virtqueue *vq = to_vvq(_vq); | |
3152 | ||
3153 | if (!vq->use_dma_api) | |
3154 | return; | |
3155 | ||
3156 | dma_unmap_single_attrs(vring_dma_dev(vq), addr, size, dir, attrs); | |
3157 | } | |
3158 | EXPORT_SYMBOL_GPL(virtqueue_dma_unmap_single_attrs); | |
3159 | ||
3160 | /** | |
3161 | * virtqueue_dma_mapping_error - check dma address | |
3162 | * @_vq: the struct virtqueue we're talking about. | |
3163 | * @addr: DMA address | |
3164 | * | |
3165 | * Returns 0 means dma valid. Other means invalid dma address. | |
3166 | */ | |
3167 | int virtqueue_dma_mapping_error(struct virtqueue *_vq, dma_addr_t addr) | |
3168 | { | |
3169 | struct vring_virtqueue *vq = to_vvq(_vq); | |
3170 | ||
3171 | if (!vq->use_dma_api) | |
3172 | return 0; | |
3173 | ||
3174 | return dma_mapping_error(vring_dma_dev(vq), addr); | |
3175 | } | |
3176 | EXPORT_SYMBOL_GPL(virtqueue_dma_mapping_error); | |
3177 | ||
c6fd4701 | 3178 | MODULE_LICENSE("GPL"); |