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06164d2b GZ |
1 | /* |
2 | * VMware VMCI Driver | |
3 | * | |
4 | * Copyright (C) 2012 VMware, Inc. All rights reserved. | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify it | |
7 | * under the terms of the GNU General Public License as published by the | |
8 | * Free Software Foundation version 2 and no later version. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, but | |
11 | * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY | |
12 | * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
13 | * for more details. | |
14 | */ | |
15 | ||
06164d2b GZ |
16 | #include <linux/vmw_vmci_defs.h> |
17 | #include <linux/vmw_vmci_api.h> | |
42281d20 | 18 | #include <linux/highmem.h> |
06164d2b | 19 | #include <linux/kernel.h> |
42281d20 | 20 | #include <linux/mm.h> |
06164d2b GZ |
21 | #include <linux/module.h> |
22 | #include <linux/mutex.h> | |
42281d20 | 23 | #include <linux/pagemap.h> |
6d6dfb4f | 24 | #include <linux/pci.h> |
42281d20 AK |
25 | #include <linux/sched.h> |
26 | #include <linux/slab.h> | |
d2f83e90 | 27 | #include <linux/uio.h> |
06164d2b | 28 | #include <linux/wait.h> |
f6dcf8e7 | 29 | #include <linux/vmalloc.h> |
06164d2b GZ |
30 | |
31 | #include "vmci_handle_array.h" | |
32 | #include "vmci_queue_pair.h" | |
33 | #include "vmci_datagram.h" | |
34 | #include "vmci_resource.h" | |
35 | #include "vmci_context.h" | |
36 | #include "vmci_driver.h" | |
37 | #include "vmci_event.h" | |
38 | #include "vmci_route.h" | |
39 | ||
40 | /* | |
41 | * In the following, we will distinguish between two kinds of VMX processes - | |
42 | * the ones with versions lower than VMCI_VERSION_NOVMVM that use specialized | |
43 | * VMCI page files in the VMX and supporting VM to VM communication and the | |
44 | * newer ones that use the guest memory directly. We will in the following | |
45 | * refer to the older VMX versions as old-style VMX'en, and the newer ones as | |
46 | * new-style VMX'en. | |
47 | * | |
48 | * The state transition datagram is as follows (the VMCIQPB_ prefix has been | |
49 | * removed for readability) - see below for more details on the transtions: | |
50 | * | |
51 | * -------------- NEW ------------- | |
52 | * | | | |
53 | * \_/ \_/ | |
54 | * CREATED_NO_MEM <-----------------> CREATED_MEM | |
55 | * | | | | |
56 | * | o-----------------------o | | |
57 | * | | | | |
58 | * \_/ \_/ \_/ | |
59 | * ATTACHED_NO_MEM <----------------> ATTACHED_MEM | |
60 | * | | | | |
61 | * | o----------------------o | | |
62 | * | | | | |
63 | * \_/ \_/ \_/ | |
64 | * SHUTDOWN_NO_MEM <----------------> SHUTDOWN_MEM | |
65 | * | | | |
66 | * | | | |
67 | * -------------> gone <------------- | |
68 | * | |
69 | * In more detail. When a VMCI queue pair is first created, it will be in the | |
70 | * VMCIQPB_NEW state. It will then move into one of the following states: | |
71 | * | |
72 | * - VMCIQPB_CREATED_NO_MEM: this state indicates that either: | |
73 | * | |
74 | * - the created was performed by a host endpoint, in which case there is | |
75 | * no backing memory yet. | |
76 | * | |
77 | * - the create was initiated by an old-style VMX, that uses | |
78 | * vmci_qp_broker_set_page_store to specify the UVAs of the queue pair at | |
79 | * a later point in time. This state can be distinguished from the one | |
80 | * above by the context ID of the creator. A host side is not allowed to | |
81 | * attach until the page store has been set. | |
82 | * | |
83 | * - VMCIQPB_CREATED_MEM: this state is the result when the queue pair | |
84 | * is created by a VMX using the queue pair device backend that | |
85 | * sets the UVAs of the queue pair immediately and stores the | |
86 | * information for later attachers. At this point, it is ready for | |
87 | * the host side to attach to it. | |
88 | * | |
89 | * Once the queue pair is in one of the created states (with the exception of | |
90 | * the case mentioned for older VMX'en above), it is possible to attach to the | |
91 | * queue pair. Again we have two new states possible: | |
92 | * | |
93 | * - VMCIQPB_ATTACHED_MEM: this state can be reached through the following | |
94 | * paths: | |
95 | * | |
96 | * - from VMCIQPB_CREATED_NO_MEM when a new-style VMX allocates a queue | |
97 | * pair, and attaches to a queue pair previously created by the host side. | |
98 | * | |
99 | * - from VMCIQPB_CREATED_MEM when the host side attaches to a queue pair | |
100 | * already created by a guest. | |
101 | * | |
102 | * - from VMCIQPB_ATTACHED_NO_MEM, when an old-style VMX calls | |
103 | * vmci_qp_broker_set_page_store (see below). | |
104 | * | |
105 | * - VMCIQPB_ATTACHED_NO_MEM: If the queue pair already was in the | |
106 | * VMCIQPB_CREATED_NO_MEM due to a host side create, an old-style VMX will | |
107 | * bring the queue pair into this state. Once vmci_qp_broker_set_page_store | |
108 | * is called to register the user memory, the VMCIQPB_ATTACH_MEM state | |
109 | * will be entered. | |
110 | * | |
111 | * From the attached queue pair, the queue pair can enter the shutdown states | |
112 | * when either side of the queue pair detaches. If the guest side detaches | |
113 | * first, the queue pair will enter the VMCIQPB_SHUTDOWN_NO_MEM state, where | |
114 | * the content of the queue pair will no longer be available. If the host | |
115 | * side detaches first, the queue pair will either enter the | |
116 | * VMCIQPB_SHUTDOWN_MEM, if the guest memory is currently mapped, or | |
117 | * VMCIQPB_SHUTDOWN_NO_MEM, if the guest memory is not mapped | |
118 | * (e.g., the host detaches while a guest is stunned). | |
119 | * | |
120 | * New-style VMX'en will also unmap guest memory, if the guest is | |
121 | * quiesced, e.g., during a snapshot operation. In that case, the guest | |
122 | * memory will no longer be available, and the queue pair will transition from | |
123 | * *_MEM state to a *_NO_MEM state. The VMX may later map the memory once more, | |
124 | * in which case the queue pair will transition from the *_NO_MEM state at that | |
125 | * point back to the *_MEM state. Note that the *_NO_MEM state may have changed, | |
126 | * since the peer may have either attached or detached in the meantime. The | |
127 | * values are laid out such that ++ on a state will move from a *_NO_MEM to a | |
128 | * *_MEM state, and vice versa. | |
129 | */ | |
130 | ||
131 | /* | |
132 | * VMCIMemcpy{To,From}QueueFunc() prototypes. Functions of these | |
133 | * types are passed around to enqueue and dequeue routines. Note that | |
134 | * often the functions passed are simply wrappers around memcpy | |
135 | * itself. | |
136 | * | |
137 | * Note: In order for the memcpy typedefs to be compatible with the VMKernel, | |
138 | * there's an unused last parameter for the hosted side. In | |
139 | * ESX, that parameter holds a buffer type. | |
140 | */ | |
141 | typedef int vmci_memcpy_to_queue_func(struct vmci_queue *queue, | |
142 | u64 queue_offset, const void *src, | |
143 | size_t src_offset, size_t size); | |
144 | typedef int vmci_memcpy_from_queue_func(void *dest, size_t dest_offset, | |
145 | const struct vmci_queue *queue, | |
146 | u64 queue_offset, size_t size); | |
147 | ||
148 | /* The Kernel specific component of the struct vmci_queue structure. */ | |
149 | struct vmci_queue_kern_if { | |
06164d2b GZ |
150 | struct mutex __mutex; /* Protects the queue. */ |
151 | struct mutex *mutex; /* Shared by producer and consumer queues. */ | |
6d6dfb4f AK |
152 | size_t num_pages; /* Number of pages incl. header. */ |
153 | bool host; /* Host or guest? */ | |
154 | union { | |
155 | struct { | |
156 | dma_addr_t *pas; | |
157 | void **vas; | |
158 | } g; /* Used by the guest. */ | |
159 | struct { | |
160 | struct page **page; | |
161 | struct page **header_page; | |
162 | } h; /* Used by the host. */ | |
163 | } u; | |
06164d2b GZ |
164 | }; |
165 | ||
166 | /* | |
167 | * This structure is opaque to the clients. | |
168 | */ | |
169 | struct vmci_qp { | |
170 | struct vmci_handle handle; | |
171 | struct vmci_queue *produce_q; | |
172 | struct vmci_queue *consume_q; | |
173 | u64 produce_q_size; | |
174 | u64 consume_q_size; | |
175 | u32 peer; | |
176 | u32 flags; | |
177 | u32 priv_flags; | |
178 | bool guest_endpoint; | |
179 | unsigned int blocked; | |
180 | unsigned int generation; | |
181 | wait_queue_head_t event; | |
182 | }; | |
183 | ||
184 | enum qp_broker_state { | |
185 | VMCIQPB_NEW, | |
186 | VMCIQPB_CREATED_NO_MEM, | |
187 | VMCIQPB_CREATED_MEM, | |
188 | VMCIQPB_ATTACHED_NO_MEM, | |
189 | VMCIQPB_ATTACHED_MEM, | |
190 | VMCIQPB_SHUTDOWN_NO_MEM, | |
191 | VMCIQPB_SHUTDOWN_MEM, | |
192 | VMCIQPB_GONE | |
193 | }; | |
194 | ||
195 | #define QPBROKERSTATE_HAS_MEM(_qpb) (_qpb->state == VMCIQPB_CREATED_MEM || \ | |
196 | _qpb->state == VMCIQPB_ATTACHED_MEM || \ | |
197 | _qpb->state == VMCIQPB_SHUTDOWN_MEM) | |
198 | ||
199 | /* | |
200 | * In the queue pair broker, we always use the guest point of view for | |
201 | * the produce and consume queue values and references, e.g., the | |
202 | * produce queue size stored is the guests produce queue size. The | |
203 | * host endpoint will need to swap these around. The only exception is | |
204 | * the local queue pairs on the host, in which case the host endpoint | |
205 | * that creates the queue pair will have the right orientation, and | |
206 | * the attaching host endpoint will need to swap. | |
207 | */ | |
208 | struct qp_entry { | |
209 | struct list_head list_item; | |
210 | struct vmci_handle handle; | |
211 | u32 peer; | |
212 | u32 flags; | |
213 | u64 produce_size; | |
214 | u64 consume_size; | |
215 | u32 ref_count; | |
216 | }; | |
217 | ||
218 | struct qp_broker_entry { | |
219 | struct vmci_resource resource; | |
220 | struct qp_entry qp; | |
221 | u32 create_id; | |
222 | u32 attach_id; | |
223 | enum qp_broker_state state; | |
224 | bool require_trusted_attach; | |
225 | bool created_by_trusted; | |
226 | bool vmci_page_files; /* Created by VMX using VMCI page files */ | |
227 | struct vmci_queue *produce_q; | |
228 | struct vmci_queue *consume_q; | |
229 | struct vmci_queue_header saved_produce_q; | |
230 | struct vmci_queue_header saved_consume_q; | |
231 | vmci_event_release_cb wakeup_cb; | |
232 | void *client_data; | |
233 | void *local_mem; /* Kernel memory for local queue pair */ | |
234 | }; | |
235 | ||
236 | struct qp_guest_endpoint { | |
237 | struct vmci_resource resource; | |
238 | struct qp_entry qp; | |
239 | u64 num_ppns; | |
240 | void *produce_q; | |
241 | void *consume_q; | |
e6389a13 | 242 | struct ppn_set ppn_set; |
06164d2b GZ |
243 | }; |
244 | ||
245 | struct qp_list { | |
246 | struct list_head head; | |
247 | struct mutex mutex; /* Protect queue list. */ | |
248 | }; | |
249 | ||
250 | static struct qp_list qp_broker_list = { | |
251 | .head = LIST_HEAD_INIT(qp_broker_list.head), | |
252 | .mutex = __MUTEX_INITIALIZER(qp_broker_list.mutex), | |
253 | }; | |
254 | ||
255 | static struct qp_list qp_guest_endpoints = { | |
256 | .head = LIST_HEAD_INIT(qp_guest_endpoints.head), | |
257 | .mutex = __MUTEX_INITIALIZER(qp_guest_endpoints.mutex), | |
258 | }; | |
259 | ||
260 | #define INVALID_VMCI_GUEST_MEM_ID 0 | |
42281d20 AK |
261 | #define QPE_NUM_PAGES(_QPE) ((u32) \ |
262 | (DIV_ROUND_UP(_QPE.produce_size, PAGE_SIZE) + \ | |
263 | DIV_ROUND_UP(_QPE.consume_size, PAGE_SIZE) + 2)) | |
06164d2b GZ |
264 | |
265 | ||
266 | /* | |
267 | * Frees kernel VA space for a given queue and its queue header, and | |
268 | * frees physical data pages. | |
269 | */ | |
270 | static void qp_free_queue(void *q, u64 size) | |
271 | { | |
272 | struct vmci_queue *queue = q; | |
273 | ||
274 | if (queue) { | |
6d6dfb4f | 275 | u64 i; |
06164d2b | 276 | |
6d6dfb4f AK |
277 | /* Given size does not include header, so add in a page here. */ |
278 | for (i = 0; i < DIV_ROUND_UP(size, PAGE_SIZE) + 1; i++) { | |
279 | dma_free_coherent(&vmci_pdev->dev, PAGE_SIZE, | |
280 | queue->kernel_if->u.g.vas[i], | |
281 | queue->kernel_if->u.g.pas[i]); | |
282 | } | |
06164d2b | 283 | |
6d6dfb4f | 284 | vfree(queue); |
06164d2b GZ |
285 | } |
286 | } | |
287 | ||
288 | /* | |
6d6dfb4f AK |
289 | * Allocates kernel queue pages of specified size with IOMMU mappings, |
290 | * plus space for the queue structure/kernel interface and the queue | |
291 | * header. | |
06164d2b GZ |
292 | */ |
293 | static void *qp_alloc_queue(u64 size, u32 flags) | |
294 | { | |
295 | u64 i; | |
296 | struct vmci_queue *queue; | |
6d6dfb4f AK |
297 | const size_t num_pages = DIV_ROUND_UP(size, PAGE_SIZE) + 1; |
298 | const size_t pas_size = num_pages * sizeof(*queue->kernel_if->u.g.pas); | |
299 | const size_t vas_size = num_pages * sizeof(*queue->kernel_if->u.g.vas); | |
300 | const size_t queue_size = | |
301 | sizeof(*queue) + sizeof(*queue->kernel_if) + | |
302 | pas_size + vas_size; | |
303 | ||
304 | queue = vmalloc(queue_size); | |
305 | if (!queue) | |
06164d2b GZ |
306 | return NULL; |
307 | ||
6d6dfb4f | 308 | queue->q_header = NULL; |
06164d2b GZ |
309 | queue->saved_header = NULL; |
310 | queue->kernel_if = (struct vmci_queue_kern_if *)(queue + 1); | |
6d6dfb4f AK |
311 | queue->kernel_if->mutex = NULL; |
312 | queue->kernel_if->num_pages = num_pages; | |
313 | queue->kernel_if->u.g.pas = (dma_addr_t *)(queue->kernel_if + 1); | |
314 | queue->kernel_if->u.g.vas = | |
315 | (void **)((u8 *)queue->kernel_if->u.g.pas + pas_size); | |
06164d2b | 316 | queue->kernel_if->host = false; |
06164d2b | 317 | |
6d6dfb4f AK |
318 | for (i = 0; i < num_pages; i++) { |
319 | queue->kernel_if->u.g.vas[i] = | |
320 | dma_alloc_coherent(&vmci_pdev->dev, PAGE_SIZE, | |
321 | &queue->kernel_if->u.g.pas[i], | |
322 | GFP_KERNEL); | |
323 | if (!queue->kernel_if->u.g.vas[i]) { | |
324 | /* Size excl. the header. */ | |
325 | qp_free_queue(queue, i * PAGE_SIZE); | |
326 | return NULL; | |
327 | } | |
06164d2b GZ |
328 | } |
329 | ||
6d6dfb4f AK |
330 | /* Queue header is the first page. */ |
331 | queue->q_header = queue->kernel_if->u.g.vas[0]; | |
06164d2b | 332 | |
6d6dfb4f | 333 | return queue; |
06164d2b GZ |
334 | } |
335 | ||
336 | /* | |
337 | * Copies from a given buffer or iovector to a VMCI Queue. Uses | |
338 | * kmap()/kunmap() to dynamically map/unmap required portions of the queue | |
339 | * by traversing the offset -> page translation structure for the queue. | |
340 | * Assumes that offset + size does not wrap around in the queue. | |
341 | */ | |
342 | static int __qp_memcpy_to_queue(struct vmci_queue *queue, | |
343 | u64 queue_offset, | |
344 | const void *src, | |
345 | size_t size, | |
346 | bool is_iovec) | |
347 | { | |
348 | struct vmci_queue_kern_if *kernel_if = queue->kernel_if; | |
349 | size_t bytes_copied = 0; | |
350 | ||
351 | while (bytes_copied < size) { | |
6d6dfb4f AK |
352 | const u64 page_index = |
353 | (queue_offset + bytes_copied) / PAGE_SIZE; | |
354 | const size_t page_offset = | |
06164d2b GZ |
355 | (queue_offset + bytes_copied) & (PAGE_SIZE - 1); |
356 | void *va; | |
357 | size_t to_copy; | |
358 | ||
6d6dfb4f AK |
359 | if (kernel_if->host) |
360 | va = kmap(kernel_if->u.h.page[page_index]); | |
361 | else | |
362 | va = kernel_if->u.g.vas[page_index + 1]; | |
363 | /* Skip header. */ | |
06164d2b GZ |
364 | |
365 | if (size - bytes_copied > PAGE_SIZE - page_offset) | |
366 | /* Enough payload to fill up from this page. */ | |
367 | to_copy = PAGE_SIZE - page_offset; | |
368 | else | |
369 | to_copy = size - bytes_copied; | |
370 | ||
371 | if (is_iovec) { | |
372 | struct iovec *iov = (struct iovec *)src; | |
373 | int err; | |
374 | ||
375 | /* The iovec will track bytes_copied internally. */ | |
376 | err = memcpy_fromiovec((u8 *)va + page_offset, | |
377 | iov, to_copy); | |
378 | if (err != 0) { | |
6d6dfb4f AK |
379 | if (kernel_if->host) |
380 | kunmap(kernel_if->u.h.page[page_index]); | |
06164d2b GZ |
381 | return VMCI_ERROR_INVALID_ARGS; |
382 | } | |
383 | } else { | |
384 | memcpy((u8 *)va + page_offset, | |
385 | (u8 *)src + bytes_copied, to_copy); | |
386 | } | |
387 | ||
388 | bytes_copied += to_copy; | |
6d6dfb4f AK |
389 | if (kernel_if->host) |
390 | kunmap(kernel_if->u.h.page[page_index]); | |
06164d2b GZ |
391 | } |
392 | ||
393 | return VMCI_SUCCESS; | |
394 | } | |
395 | ||
396 | /* | |
397 | * Copies to a given buffer or iovector from a VMCI Queue. Uses | |
398 | * kmap()/kunmap() to dynamically map/unmap required portions of the queue | |
399 | * by traversing the offset -> page translation structure for the queue. | |
400 | * Assumes that offset + size does not wrap around in the queue. | |
401 | */ | |
402 | static int __qp_memcpy_from_queue(void *dest, | |
403 | const struct vmci_queue *queue, | |
404 | u64 queue_offset, | |
405 | size_t size, | |
406 | bool is_iovec) | |
407 | { | |
408 | struct vmci_queue_kern_if *kernel_if = queue->kernel_if; | |
409 | size_t bytes_copied = 0; | |
410 | ||
411 | while (bytes_copied < size) { | |
6d6dfb4f AK |
412 | const u64 page_index = |
413 | (queue_offset + bytes_copied) / PAGE_SIZE; | |
414 | const size_t page_offset = | |
06164d2b GZ |
415 | (queue_offset + bytes_copied) & (PAGE_SIZE - 1); |
416 | void *va; | |
417 | size_t to_copy; | |
418 | ||
6d6dfb4f AK |
419 | if (kernel_if->host) |
420 | va = kmap(kernel_if->u.h.page[page_index]); | |
421 | else | |
422 | va = kernel_if->u.g.vas[page_index + 1]; | |
423 | /* Skip header. */ | |
06164d2b GZ |
424 | |
425 | if (size - bytes_copied > PAGE_SIZE - page_offset) | |
426 | /* Enough payload to fill up this page. */ | |
427 | to_copy = PAGE_SIZE - page_offset; | |
428 | else | |
429 | to_copy = size - bytes_copied; | |
430 | ||
431 | if (is_iovec) { | |
432 | struct iovec *iov = (struct iovec *)dest; | |
433 | int err; | |
434 | ||
435 | /* The iovec will track bytes_copied internally. */ | |
436 | err = memcpy_toiovec(iov, (u8 *)va + page_offset, | |
437 | to_copy); | |
438 | if (err != 0) { | |
6d6dfb4f AK |
439 | if (kernel_if->host) |
440 | kunmap(kernel_if->u.h.page[page_index]); | |
06164d2b GZ |
441 | return VMCI_ERROR_INVALID_ARGS; |
442 | } | |
443 | } else { | |
444 | memcpy((u8 *)dest + bytes_copied, | |
445 | (u8 *)va + page_offset, to_copy); | |
446 | } | |
447 | ||
448 | bytes_copied += to_copy; | |
6d6dfb4f AK |
449 | if (kernel_if->host) |
450 | kunmap(kernel_if->u.h.page[page_index]); | |
06164d2b GZ |
451 | } |
452 | ||
453 | return VMCI_SUCCESS; | |
454 | } | |
455 | ||
456 | /* | |
457 | * Allocates two list of PPNs --- one for the pages in the produce queue, | |
458 | * and the other for the pages in the consume queue. Intializes the list | |
459 | * of PPNs with the page frame numbers of the KVA for the two queues (and | |
460 | * the queue headers). | |
461 | */ | |
462 | static int qp_alloc_ppn_set(void *prod_q, | |
463 | u64 num_produce_pages, | |
464 | void *cons_q, | |
e6389a13 | 465 | u64 num_consume_pages, struct ppn_set *ppn_set) |
06164d2b GZ |
466 | { |
467 | u32 *produce_ppns; | |
468 | u32 *consume_ppns; | |
469 | struct vmci_queue *produce_q = prod_q; | |
470 | struct vmci_queue *consume_q = cons_q; | |
471 | u64 i; | |
472 | ||
473 | if (!produce_q || !num_produce_pages || !consume_q || | |
474 | !num_consume_pages || !ppn_set) | |
475 | return VMCI_ERROR_INVALID_ARGS; | |
476 | ||
477 | if (ppn_set->initialized) | |
478 | return VMCI_ERROR_ALREADY_EXISTS; | |
479 | ||
480 | produce_ppns = | |
481 | kmalloc(num_produce_pages * sizeof(*produce_ppns), GFP_KERNEL); | |
482 | if (!produce_ppns) | |
483 | return VMCI_ERROR_NO_MEM; | |
484 | ||
485 | consume_ppns = | |
486 | kmalloc(num_consume_pages * sizeof(*consume_ppns), GFP_KERNEL); | |
487 | if (!consume_ppns) { | |
488 | kfree(produce_ppns); | |
489 | return VMCI_ERROR_NO_MEM; | |
490 | } | |
491 | ||
6d6dfb4f | 492 | for (i = 0; i < num_produce_pages; i++) { |
06164d2b GZ |
493 | unsigned long pfn; |
494 | ||
495 | produce_ppns[i] = | |
6d6dfb4f | 496 | produce_q->kernel_if->u.g.pas[i] >> PAGE_SHIFT; |
06164d2b GZ |
497 | pfn = produce_ppns[i]; |
498 | ||
499 | /* Fail allocation if PFN isn't supported by hypervisor. */ | |
500 | if (sizeof(pfn) > sizeof(*produce_ppns) | |
501 | && pfn != produce_ppns[i]) | |
502 | goto ppn_error; | |
503 | } | |
504 | ||
6d6dfb4f | 505 | for (i = 0; i < num_consume_pages; i++) { |
06164d2b GZ |
506 | unsigned long pfn; |
507 | ||
508 | consume_ppns[i] = | |
6d6dfb4f | 509 | consume_q->kernel_if->u.g.pas[i] >> PAGE_SHIFT; |
06164d2b GZ |
510 | pfn = consume_ppns[i]; |
511 | ||
512 | /* Fail allocation if PFN isn't supported by hypervisor. */ | |
513 | if (sizeof(pfn) > sizeof(*consume_ppns) | |
514 | && pfn != consume_ppns[i]) | |
515 | goto ppn_error; | |
516 | } | |
517 | ||
518 | ppn_set->num_produce_pages = num_produce_pages; | |
519 | ppn_set->num_consume_pages = num_consume_pages; | |
520 | ppn_set->produce_ppns = produce_ppns; | |
521 | ppn_set->consume_ppns = consume_ppns; | |
522 | ppn_set->initialized = true; | |
523 | return VMCI_SUCCESS; | |
524 | ||
525 | ppn_error: | |
526 | kfree(produce_ppns); | |
527 | kfree(consume_ppns); | |
528 | return VMCI_ERROR_INVALID_ARGS; | |
529 | } | |
530 | ||
531 | /* | |
532 | * Frees the two list of PPNs for a queue pair. | |
533 | */ | |
e6389a13 | 534 | static void qp_free_ppn_set(struct ppn_set *ppn_set) |
06164d2b GZ |
535 | { |
536 | if (ppn_set->initialized) { | |
537 | /* Do not call these functions on NULL inputs. */ | |
538 | kfree(ppn_set->produce_ppns); | |
539 | kfree(ppn_set->consume_ppns); | |
540 | } | |
541 | memset(ppn_set, 0, sizeof(*ppn_set)); | |
542 | } | |
543 | ||
544 | /* | |
545 | * Populates the list of PPNs in the hypercall structure with the PPNS | |
546 | * of the produce queue and the consume queue. | |
547 | */ | |
e6389a13 | 548 | static int qp_populate_ppn_set(u8 *call_buf, const struct ppn_set *ppn_set) |
06164d2b GZ |
549 | { |
550 | memcpy(call_buf, ppn_set->produce_ppns, | |
551 | ppn_set->num_produce_pages * sizeof(*ppn_set->produce_ppns)); | |
552 | memcpy(call_buf + | |
553 | ppn_set->num_produce_pages * sizeof(*ppn_set->produce_ppns), | |
554 | ppn_set->consume_ppns, | |
555 | ppn_set->num_consume_pages * sizeof(*ppn_set->consume_ppns)); | |
556 | ||
557 | return VMCI_SUCCESS; | |
558 | } | |
559 | ||
560 | static int qp_memcpy_to_queue(struct vmci_queue *queue, | |
561 | u64 queue_offset, | |
562 | const void *src, size_t src_offset, size_t size) | |
563 | { | |
564 | return __qp_memcpy_to_queue(queue, queue_offset, | |
565 | (u8 *)src + src_offset, size, false); | |
566 | } | |
567 | ||
568 | static int qp_memcpy_from_queue(void *dest, | |
569 | size_t dest_offset, | |
570 | const struct vmci_queue *queue, | |
571 | u64 queue_offset, size_t size) | |
572 | { | |
573 | return __qp_memcpy_from_queue((u8 *)dest + dest_offset, | |
574 | queue, queue_offset, size, false); | |
575 | } | |
576 | ||
577 | /* | |
578 | * Copies from a given iovec from a VMCI Queue. | |
579 | */ | |
580 | static int qp_memcpy_to_queue_iov(struct vmci_queue *queue, | |
581 | u64 queue_offset, | |
582 | const void *src, | |
583 | size_t src_offset, size_t size) | |
584 | { | |
585 | ||
586 | /* | |
587 | * We ignore src_offset because src is really a struct iovec * and will | |
588 | * maintain offset internally. | |
589 | */ | |
590 | return __qp_memcpy_to_queue(queue, queue_offset, src, size, true); | |
591 | } | |
592 | ||
593 | /* | |
594 | * Copies to a given iovec from a VMCI Queue. | |
595 | */ | |
596 | static int qp_memcpy_from_queue_iov(void *dest, | |
597 | size_t dest_offset, | |
598 | const struct vmci_queue *queue, | |
599 | u64 queue_offset, size_t size) | |
600 | { | |
601 | /* | |
602 | * We ignore dest_offset because dest is really a struct iovec * and | |
603 | * will maintain offset internally. | |
604 | */ | |
605 | return __qp_memcpy_from_queue(dest, queue, queue_offset, size, true); | |
606 | } | |
607 | ||
608 | /* | |
609 | * Allocates kernel VA space of specified size plus space for the queue | |
610 | * and kernel interface. This is different from the guest queue allocator, | |
611 | * because we do not allocate our own queue header/data pages here but | |
612 | * share those of the guest. | |
613 | */ | |
614 | static struct vmci_queue *qp_host_alloc_queue(u64 size) | |
615 | { | |
616 | struct vmci_queue *queue; | |
42281d20 | 617 | const size_t num_pages = DIV_ROUND_UP(size, PAGE_SIZE) + 1; |
06164d2b GZ |
618 | const size_t queue_size = sizeof(*queue) + sizeof(*(queue->kernel_if)); |
619 | const size_t queue_page_size = | |
6d6dfb4f | 620 | num_pages * sizeof(*queue->kernel_if->u.h.page); |
06164d2b GZ |
621 | |
622 | queue = kzalloc(queue_size + queue_page_size, GFP_KERNEL); | |
623 | if (queue) { | |
624 | queue->q_header = NULL; | |
625 | queue->saved_header = NULL; | |
6d6dfb4f | 626 | queue->kernel_if = (struct vmci_queue_kern_if *)(queue + 1); |
06164d2b GZ |
627 | queue->kernel_if->host = true; |
628 | queue->kernel_if->mutex = NULL; | |
629 | queue->kernel_if->num_pages = num_pages; | |
6d6dfb4f | 630 | queue->kernel_if->u.h.header_page = |
06164d2b | 631 | (struct page **)((u8 *)queue + queue_size); |
6d6dfb4f AK |
632 | queue->kernel_if->u.h.page = |
633 | &queue->kernel_if->u.h.header_page[1]; | |
06164d2b GZ |
634 | } |
635 | ||
636 | return queue; | |
637 | } | |
638 | ||
639 | /* | |
640 | * Frees kernel memory for a given queue (header plus translation | |
641 | * structure). | |
642 | */ | |
643 | static void qp_host_free_queue(struct vmci_queue *queue, u64 queue_size) | |
644 | { | |
645 | kfree(queue); | |
646 | } | |
647 | ||
648 | /* | |
649 | * Initialize the mutex for the pair of queues. This mutex is used to | |
650 | * protect the q_header and the buffer from changing out from under any | |
651 | * users of either queue. Of course, it's only any good if the mutexes | |
652 | * are actually acquired. Queue structure must lie on non-paged memory | |
653 | * or we cannot guarantee access to the mutex. | |
654 | */ | |
655 | static void qp_init_queue_mutex(struct vmci_queue *produce_q, | |
656 | struct vmci_queue *consume_q) | |
657 | { | |
658 | /* | |
659 | * Only the host queue has shared state - the guest queues do not | |
660 | * need to synchronize access using a queue mutex. | |
661 | */ | |
662 | ||
663 | if (produce_q->kernel_if->host) { | |
664 | produce_q->kernel_if->mutex = &produce_q->kernel_if->__mutex; | |
665 | consume_q->kernel_if->mutex = &produce_q->kernel_if->__mutex; | |
666 | mutex_init(produce_q->kernel_if->mutex); | |
667 | } | |
668 | } | |
669 | ||
670 | /* | |
671 | * Cleans up the mutex for the pair of queues. | |
672 | */ | |
673 | static void qp_cleanup_queue_mutex(struct vmci_queue *produce_q, | |
674 | struct vmci_queue *consume_q) | |
675 | { | |
676 | if (produce_q->kernel_if->host) { | |
677 | produce_q->kernel_if->mutex = NULL; | |
678 | consume_q->kernel_if->mutex = NULL; | |
679 | } | |
680 | } | |
681 | ||
682 | /* | |
683 | * Acquire the mutex for the queue. Note that the produce_q and | |
684 | * the consume_q share a mutex. So, only one of the two need to | |
685 | * be passed in to this routine. Either will work just fine. | |
686 | */ | |
687 | static void qp_acquire_queue_mutex(struct vmci_queue *queue) | |
688 | { | |
689 | if (queue->kernel_if->host) | |
690 | mutex_lock(queue->kernel_if->mutex); | |
691 | } | |
692 | ||
693 | /* | |
694 | * Release the mutex for the queue. Note that the produce_q and | |
695 | * the consume_q share a mutex. So, only one of the two need to | |
696 | * be passed in to this routine. Either will work just fine. | |
697 | */ | |
698 | static void qp_release_queue_mutex(struct vmci_queue *queue) | |
699 | { | |
700 | if (queue->kernel_if->host) | |
701 | mutex_unlock(queue->kernel_if->mutex); | |
702 | } | |
703 | ||
704 | /* | |
705 | * Helper function to release pages in the PageStoreAttachInfo | |
706 | * previously obtained using get_user_pages. | |
707 | */ | |
708 | static void qp_release_pages(struct page **pages, | |
709 | u64 num_pages, bool dirty) | |
710 | { | |
711 | int i; | |
712 | ||
713 | for (i = 0; i < num_pages; i++) { | |
714 | if (dirty) | |
715 | set_page_dirty(pages[i]); | |
716 | ||
717 | page_cache_release(pages[i]); | |
718 | pages[i] = NULL; | |
719 | } | |
720 | } | |
721 | ||
722 | /* | |
723 | * Lock the user pages referenced by the {produce,consume}Buffer | |
724 | * struct into memory and populate the {produce,consume}Pages | |
725 | * arrays in the attach structure with them. | |
726 | */ | |
727 | static int qp_host_get_user_memory(u64 produce_uva, | |
728 | u64 consume_uva, | |
729 | struct vmci_queue *produce_q, | |
730 | struct vmci_queue *consume_q) | |
731 | { | |
732 | int retval; | |
733 | int err = VMCI_SUCCESS; | |
734 | ||
240ddd49 JK |
735 | retval = get_user_pages_fast((uintptr_t) produce_uva, |
736 | produce_q->kernel_if->num_pages, 1, | |
737 | produce_q->kernel_if->u.h.header_page); | |
06164d2b GZ |
738 | if (retval < produce_q->kernel_if->num_pages) { |
739 | pr_warn("get_user_pages(produce) failed (retval=%d)", retval); | |
6d6dfb4f AK |
740 | qp_release_pages(produce_q->kernel_if->u.h.header_page, |
741 | retval, false); | |
06164d2b GZ |
742 | err = VMCI_ERROR_NO_MEM; |
743 | goto out; | |
744 | } | |
745 | ||
240ddd49 JK |
746 | retval = get_user_pages_fast((uintptr_t) consume_uva, |
747 | consume_q->kernel_if->num_pages, 1, | |
748 | consume_q->kernel_if->u.h.header_page); | |
06164d2b GZ |
749 | if (retval < consume_q->kernel_if->num_pages) { |
750 | pr_warn("get_user_pages(consume) failed (retval=%d)", retval); | |
6d6dfb4f AK |
751 | qp_release_pages(consume_q->kernel_if->u.h.header_page, |
752 | retval, false); | |
753 | qp_release_pages(produce_q->kernel_if->u.h.header_page, | |
06164d2b GZ |
754 | produce_q->kernel_if->num_pages, false); |
755 | err = VMCI_ERROR_NO_MEM; | |
756 | } | |
757 | ||
758 | out: | |
06164d2b GZ |
759 | return err; |
760 | } | |
761 | ||
762 | /* | |
763 | * Registers the specification of the user pages used for backing a queue | |
764 | * pair. Enough information to map in pages is stored in the OS specific | |
765 | * part of the struct vmci_queue structure. | |
766 | */ | |
767 | static int qp_host_register_user_memory(struct vmci_qp_page_store *page_store, | |
768 | struct vmci_queue *produce_q, | |
769 | struct vmci_queue *consume_q) | |
770 | { | |
771 | u64 produce_uva; | |
772 | u64 consume_uva; | |
773 | ||
774 | /* | |
775 | * The new style and the old style mapping only differs in | |
776 | * that we either get a single or two UVAs, so we split the | |
777 | * single UVA range at the appropriate spot. | |
778 | */ | |
779 | produce_uva = page_store->pages; | |
780 | consume_uva = page_store->pages + | |
781 | produce_q->kernel_if->num_pages * PAGE_SIZE; | |
782 | return qp_host_get_user_memory(produce_uva, consume_uva, produce_q, | |
783 | consume_q); | |
784 | } | |
785 | ||
786 | /* | |
787 | * Releases and removes the references to user pages stored in the attach | |
788 | * struct. Pages are released from the page cache and may become | |
789 | * swappable again. | |
790 | */ | |
791 | static void qp_host_unregister_user_memory(struct vmci_queue *produce_q, | |
792 | struct vmci_queue *consume_q) | |
793 | { | |
6d6dfb4f | 794 | qp_release_pages(produce_q->kernel_if->u.h.header_page, |
06164d2b | 795 | produce_q->kernel_if->num_pages, true); |
6d6dfb4f AK |
796 | memset(produce_q->kernel_if->u.h.header_page, 0, |
797 | sizeof(*produce_q->kernel_if->u.h.header_page) * | |
06164d2b | 798 | produce_q->kernel_if->num_pages); |
6d6dfb4f | 799 | qp_release_pages(consume_q->kernel_if->u.h.header_page, |
06164d2b | 800 | consume_q->kernel_if->num_pages, true); |
6d6dfb4f AK |
801 | memset(consume_q->kernel_if->u.h.header_page, 0, |
802 | sizeof(*consume_q->kernel_if->u.h.header_page) * | |
06164d2b GZ |
803 | consume_q->kernel_if->num_pages); |
804 | } | |
805 | ||
806 | /* | |
807 | * Once qp_host_register_user_memory has been performed on a | |
808 | * queue, the queue pair headers can be mapped into the | |
809 | * kernel. Once mapped, they must be unmapped with | |
810 | * qp_host_unmap_queues prior to calling | |
811 | * qp_host_unregister_user_memory. | |
812 | * Pages are pinned. | |
813 | */ | |
814 | static int qp_host_map_queues(struct vmci_queue *produce_q, | |
815 | struct vmci_queue *consume_q) | |
816 | { | |
817 | int result; | |
818 | ||
819 | if (!produce_q->q_header || !consume_q->q_header) { | |
820 | struct page *headers[2]; | |
821 | ||
822 | if (produce_q->q_header != consume_q->q_header) | |
823 | return VMCI_ERROR_QUEUEPAIR_MISMATCH; | |
824 | ||
6d6dfb4f AK |
825 | if (produce_q->kernel_if->u.h.header_page == NULL || |
826 | *produce_q->kernel_if->u.h.header_page == NULL) | |
06164d2b GZ |
827 | return VMCI_ERROR_UNAVAILABLE; |
828 | ||
6d6dfb4f AK |
829 | headers[0] = *produce_q->kernel_if->u.h.header_page; |
830 | headers[1] = *consume_q->kernel_if->u.h.header_page; | |
06164d2b GZ |
831 | |
832 | produce_q->q_header = vmap(headers, 2, VM_MAP, PAGE_KERNEL); | |
833 | if (produce_q->q_header != NULL) { | |
834 | consume_q->q_header = | |
835 | (struct vmci_queue_header *)((u8 *) | |
836 | produce_q->q_header + | |
837 | PAGE_SIZE); | |
838 | result = VMCI_SUCCESS; | |
839 | } else { | |
840 | pr_warn("vmap failed\n"); | |
841 | result = VMCI_ERROR_NO_MEM; | |
842 | } | |
843 | } else { | |
844 | result = VMCI_SUCCESS; | |
845 | } | |
846 | ||
847 | return result; | |
848 | } | |
849 | ||
850 | /* | |
851 | * Unmaps previously mapped queue pair headers from the kernel. | |
852 | * Pages are unpinned. | |
853 | */ | |
854 | static int qp_host_unmap_queues(u32 gid, | |
855 | struct vmci_queue *produce_q, | |
856 | struct vmci_queue *consume_q) | |
857 | { | |
858 | if (produce_q->q_header) { | |
859 | if (produce_q->q_header < consume_q->q_header) | |
860 | vunmap(produce_q->q_header); | |
861 | else | |
862 | vunmap(consume_q->q_header); | |
863 | ||
864 | produce_q->q_header = NULL; | |
865 | consume_q->q_header = NULL; | |
866 | } | |
867 | ||
868 | return VMCI_SUCCESS; | |
869 | } | |
870 | ||
871 | /* | |
872 | * Finds the entry in the list corresponding to a given handle. Assumes | |
873 | * that the list is locked. | |
874 | */ | |
875 | static struct qp_entry *qp_list_find(struct qp_list *qp_list, | |
876 | struct vmci_handle handle) | |
877 | { | |
878 | struct qp_entry *entry; | |
879 | ||
880 | if (vmci_handle_is_invalid(handle)) | |
881 | return NULL; | |
882 | ||
883 | list_for_each_entry(entry, &qp_list->head, list_item) { | |
884 | if (vmci_handle_is_equal(entry->handle, handle)) | |
885 | return entry; | |
886 | } | |
887 | ||
888 | return NULL; | |
889 | } | |
890 | ||
891 | /* | |
892 | * Finds the entry in the list corresponding to a given handle. | |
893 | */ | |
894 | static struct qp_guest_endpoint * | |
895 | qp_guest_handle_to_entry(struct vmci_handle handle) | |
896 | { | |
897 | struct qp_guest_endpoint *entry; | |
898 | struct qp_entry *qp = qp_list_find(&qp_guest_endpoints, handle); | |
899 | ||
900 | entry = qp ? container_of( | |
901 | qp, struct qp_guest_endpoint, qp) : NULL; | |
902 | return entry; | |
903 | } | |
904 | ||
905 | /* | |
906 | * Finds the entry in the list corresponding to a given handle. | |
907 | */ | |
908 | static struct qp_broker_entry * | |
909 | qp_broker_handle_to_entry(struct vmci_handle handle) | |
910 | { | |
911 | struct qp_broker_entry *entry; | |
912 | struct qp_entry *qp = qp_list_find(&qp_broker_list, handle); | |
913 | ||
914 | entry = qp ? container_of( | |
915 | qp, struct qp_broker_entry, qp) : NULL; | |
916 | return entry; | |
917 | } | |
918 | ||
919 | /* | |
920 | * Dispatches a queue pair event message directly into the local event | |
921 | * queue. | |
922 | */ | |
923 | static int qp_notify_peer_local(bool attach, struct vmci_handle handle) | |
924 | { | |
925 | u32 context_id = vmci_get_context_id(); | |
926 | struct vmci_event_qp ev; | |
927 | ||
928 | ev.msg.hdr.dst = vmci_make_handle(context_id, VMCI_EVENT_HANDLER); | |
929 | ev.msg.hdr.src = vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID, | |
930 | VMCI_CONTEXT_RESOURCE_ID); | |
931 | ev.msg.hdr.payload_size = sizeof(ev) - sizeof(ev.msg.hdr); | |
932 | ev.msg.event_data.event = | |
933 | attach ? VMCI_EVENT_QP_PEER_ATTACH : VMCI_EVENT_QP_PEER_DETACH; | |
934 | ev.payload.peer_id = context_id; | |
935 | ev.payload.handle = handle; | |
936 | ||
937 | return vmci_event_dispatch(&ev.msg.hdr); | |
938 | } | |
939 | ||
940 | /* | |
941 | * Allocates and initializes a qp_guest_endpoint structure. | |
942 | * Allocates a queue_pair rid (and handle) iff the given entry has | |
943 | * an invalid handle. 0 through VMCI_RESERVED_RESOURCE_ID_MAX | |
944 | * are reserved handles. Assumes that the QP list mutex is held | |
945 | * by the caller. | |
946 | */ | |
947 | static struct qp_guest_endpoint * | |
948 | qp_guest_endpoint_create(struct vmci_handle handle, | |
949 | u32 peer, | |
950 | u32 flags, | |
951 | u64 produce_size, | |
952 | u64 consume_size, | |
953 | void *produce_q, | |
954 | void *consume_q) | |
955 | { | |
956 | int result; | |
957 | struct qp_guest_endpoint *entry; | |
958 | /* One page each for the queue headers. */ | |
42281d20 AK |
959 | const u64 num_ppns = DIV_ROUND_UP(produce_size, PAGE_SIZE) + |
960 | DIV_ROUND_UP(consume_size, PAGE_SIZE) + 2; | |
06164d2b GZ |
961 | |
962 | if (vmci_handle_is_invalid(handle)) { | |
963 | u32 context_id = vmci_get_context_id(); | |
964 | ||
965 | handle = vmci_make_handle(context_id, VMCI_INVALID_ID); | |
966 | } | |
967 | ||
968 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | |
969 | if (entry) { | |
970 | entry->qp.peer = peer; | |
971 | entry->qp.flags = flags; | |
972 | entry->qp.produce_size = produce_size; | |
973 | entry->qp.consume_size = consume_size; | |
974 | entry->qp.ref_count = 0; | |
975 | entry->num_ppns = num_ppns; | |
976 | entry->produce_q = produce_q; | |
977 | entry->consume_q = consume_q; | |
978 | INIT_LIST_HEAD(&entry->qp.list_item); | |
979 | ||
980 | /* Add resource obj */ | |
981 | result = vmci_resource_add(&entry->resource, | |
982 | VMCI_RESOURCE_TYPE_QPAIR_GUEST, | |
983 | handle); | |
984 | entry->qp.handle = vmci_resource_handle(&entry->resource); | |
985 | if ((result != VMCI_SUCCESS) || | |
986 | qp_list_find(&qp_guest_endpoints, entry->qp.handle)) { | |
987 | pr_warn("Failed to add new resource (handle=0x%x:0x%x), error: %d", | |
988 | handle.context, handle.resource, result); | |
989 | kfree(entry); | |
990 | entry = NULL; | |
991 | } | |
992 | } | |
993 | return entry; | |
994 | } | |
995 | ||
996 | /* | |
997 | * Frees a qp_guest_endpoint structure. | |
998 | */ | |
999 | static void qp_guest_endpoint_destroy(struct qp_guest_endpoint *entry) | |
1000 | { | |
1001 | qp_free_ppn_set(&entry->ppn_set); | |
1002 | qp_cleanup_queue_mutex(entry->produce_q, entry->consume_q); | |
1003 | qp_free_queue(entry->produce_q, entry->qp.produce_size); | |
1004 | qp_free_queue(entry->consume_q, entry->qp.consume_size); | |
1005 | /* Unlink from resource hash table and free callback */ | |
1006 | vmci_resource_remove(&entry->resource); | |
1007 | ||
1008 | kfree(entry); | |
1009 | } | |
1010 | ||
1011 | /* | |
1012 | * Helper to make a queue_pairAlloc hypercall when the driver is | |
1013 | * supporting a guest device. | |
1014 | */ | |
1015 | static int qp_alloc_hypercall(const struct qp_guest_endpoint *entry) | |
1016 | { | |
1017 | struct vmci_qp_alloc_msg *alloc_msg; | |
1018 | size_t msg_size; | |
1019 | int result; | |
1020 | ||
1021 | if (!entry || entry->num_ppns <= 2) | |
1022 | return VMCI_ERROR_INVALID_ARGS; | |
1023 | ||
1024 | msg_size = sizeof(*alloc_msg) + | |
1025 | (size_t) entry->num_ppns * sizeof(u32); | |
1026 | alloc_msg = kmalloc(msg_size, GFP_KERNEL); | |
1027 | if (!alloc_msg) | |
1028 | return VMCI_ERROR_NO_MEM; | |
1029 | ||
1030 | alloc_msg->hdr.dst = vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID, | |
1031 | VMCI_QUEUEPAIR_ALLOC); | |
1032 | alloc_msg->hdr.src = VMCI_ANON_SRC_HANDLE; | |
1033 | alloc_msg->hdr.payload_size = msg_size - VMCI_DG_HEADERSIZE; | |
1034 | alloc_msg->handle = entry->qp.handle; | |
1035 | alloc_msg->peer = entry->qp.peer; | |
1036 | alloc_msg->flags = entry->qp.flags; | |
1037 | alloc_msg->produce_size = entry->qp.produce_size; | |
1038 | alloc_msg->consume_size = entry->qp.consume_size; | |
1039 | alloc_msg->num_ppns = entry->num_ppns; | |
1040 | ||
1041 | result = qp_populate_ppn_set((u8 *)alloc_msg + sizeof(*alloc_msg), | |
1042 | &entry->ppn_set); | |
1043 | if (result == VMCI_SUCCESS) | |
1044 | result = vmci_send_datagram(&alloc_msg->hdr); | |
1045 | ||
1046 | kfree(alloc_msg); | |
1047 | ||
1048 | return result; | |
1049 | } | |
1050 | ||
1051 | /* | |
1052 | * Helper to make a queue_pairDetach hypercall when the driver is | |
1053 | * supporting a guest device. | |
1054 | */ | |
1055 | static int qp_detatch_hypercall(struct vmci_handle handle) | |
1056 | { | |
1057 | struct vmci_qp_detach_msg detach_msg; | |
1058 | ||
1059 | detach_msg.hdr.dst = vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID, | |
1060 | VMCI_QUEUEPAIR_DETACH); | |
1061 | detach_msg.hdr.src = VMCI_ANON_SRC_HANDLE; | |
1062 | detach_msg.hdr.payload_size = sizeof(handle); | |
1063 | detach_msg.handle = handle; | |
1064 | ||
1065 | return vmci_send_datagram(&detach_msg.hdr); | |
1066 | } | |
1067 | ||
1068 | /* | |
1069 | * Adds the given entry to the list. Assumes that the list is locked. | |
1070 | */ | |
1071 | static void qp_list_add_entry(struct qp_list *qp_list, struct qp_entry *entry) | |
1072 | { | |
1073 | if (entry) | |
1074 | list_add(&entry->list_item, &qp_list->head); | |
1075 | } | |
1076 | ||
1077 | /* | |
1078 | * Removes the given entry from the list. Assumes that the list is locked. | |
1079 | */ | |
1080 | static void qp_list_remove_entry(struct qp_list *qp_list, | |
1081 | struct qp_entry *entry) | |
1082 | { | |
1083 | if (entry) | |
1084 | list_del(&entry->list_item); | |
1085 | } | |
1086 | ||
1087 | /* | |
1088 | * Helper for VMCI queue_pair detach interface. Frees the physical | |
1089 | * pages for the queue pair. | |
1090 | */ | |
1091 | static int qp_detatch_guest_work(struct vmci_handle handle) | |
1092 | { | |
1093 | int result; | |
1094 | struct qp_guest_endpoint *entry; | |
1095 | u32 ref_count = ~0; /* To avoid compiler warning below */ | |
1096 | ||
1097 | mutex_lock(&qp_guest_endpoints.mutex); | |
1098 | ||
1099 | entry = qp_guest_handle_to_entry(handle); | |
1100 | if (!entry) { | |
1101 | mutex_unlock(&qp_guest_endpoints.mutex); | |
1102 | return VMCI_ERROR_NOT_FOUND; | |
1103 | } | |
1104 | ||
1105 | if (entry->qp.flags & VMCI_QPFLAG_LOCAL) { | |
1106 | result = VMCI_SUCCESS; | |
1107 | ||
1108 | if (entry->qp.ref_count > 1) { | |
1109 | result = qp_notify_peer_local(false, handle); | |
1110 | /* | |
1111 | * We can fail to notify a local queuepair | |
1112 | * because we can't allocate. We still want | |
1113 | * to release the entry if that happens, so | |
1114 | * don't bail out yet. | |
1115 | */ | |
1116 | } | |
1117 | } else { | |
1118 | result = qp_detatch_hypercall(handle); | |
1119 | if (result < VMCI_SUCCESS) { | |
1120 | /* | |
1121 | * We failed to notify a non-local queuepair. | |
1122 | * That other queuepair might still be | |
1123 | * accessing the shared memory, so don't | |
1124 | * release the entry yet. It will get cleaned | |
1125 | * up by VMCIqueue_pair_Exit() if necessary | |
1126 | * (assuming we are going away, otherwise why | |
1127 | * did this fail?). | |
1128 | */ | |
1129 | ||
1130 | mutex_unlock(&qp_guest_endpoints.mutex); | |
1131 | return result; | |
1132 | } | |
1133 | } | |
1134 | ||
1135 | /* | |
1136 | * If we get here then we either failed to notify a local queuepair, or | |
1137 | * we succeeded in all cases. Release the entry if required. | |
1138 | */ | |
1139 | ||
1140 | entry->qp.ref_count--; | |
1141 | if (entry->qp.ref_count == 0) | |
1142 | qp_list_remove_entry(&qp_guest_endpoints, &entry->qp); | |
1143 | ||
1144 | /* If we didn't remove the entry, this could change once we unlock. */ | |
1145 | if (entry) | |
1146 | ref_count = entry->qp.ref_count; | |
1147 | ||
1148 | mutex_unlock(&qp_guest_endpoints.mutex); | |
1149 | ||
1150 | if (ref_count == 0) | |
1151 | qp_guest_endpoint_destroy(entry); | |
1152 | ||
1153 | return result; | |
1154 | } | |
1155 | ||
1156 | /* | |
1157 | * This functions handles the actual allocation of a VMCI queue | |
1158 | * pair guest endpoint. Allocates physical pages for the queue | |
1159 | * pair. It makes OS dependent calls through generic wrappers. | |
1160 | */ | |
1161 | static int qp_alloc_guest_work(struct vmci_handle *handle, | |
1162 | struct vmci_queue **produce_q, | |
1163 | u64 produce_size, | |
1164 | struct vmci_queue **consume_q, | |
1165 | u64 consume_size, | |
1166 | u32 peer, | |
1167 | u32 flags, | |
1168 | u32 priv_flags) | |
1169 | { | |
1170 | const u64 num_produce_pages = | |
42281d20 | 1171 | DIV_ROUND_UP(produce_size, PAGE_SIZE) + 1; |
06164d2b | 1172 | const u64 num_consume_pages = |
42281d20 | 1173 | DIV_ROUND_UP(consume_size, PAGE_SIZE) + 1; |
06164d2b GZ |
1174 | void *my_produce_q = NULL; |
1175 | void *my_consume_q = NULL; | |
1176 | int result; | |
1177 | struct qp_guest_endpoint *queue_pair_entry = NULL; | |
1178 | ||
1179 | if (priv_flags != VMCI_NO_PRIVILEGE_FLAGS) | |
1180 | return VMCI_ERROR_NO_ACCESS; | |
1181 | ||
1182 | mutex_lock(&qp_guest_endpoints.mutex); | |
1183 | ||
1184 | queue_pair_entry = qp_guest_handle_to_entry(*handle); | |
1185 | if (queue_pair_entry) { | |
1186 | if (queue_pair_entry->qp.flags & VMCI_QPFLAG_LOCAL) { | |
1187 | /* Local attach case. */ | |
1188 | if (queue_pair_entry->qp.ref_count > 1) { | |
1189 | pr_devel("Error attempting to attach more than once\n"); | |
1190 | result = VMCI_ERROR_UNAVAILABLE; | |
1191 | goto error_keep_entry; | |
1192 | } | |
1193 | ||
1194 | if (queue_pair_entry->qp.produce_size != consume_size || | |
1195 | queue_pair_entry->qp.consume_size != | |
1196 | produce_size || | |
1197 | queue_pair_entry->qp.flags != | |
1198 | (flags & ~VMCI_QPFLAG_ATTACH_ONLY)) { | |
1199 | pr_devel("Error mismatched queue pair in local attach\n"); | |
1200 | result = VMCI_ERROR_QUEUEPAIR_MISMATCH; | |
1201 | goto error_keep_entry; | |
1202 | } | |
1203 | ||
1204 | /* | |
1205 | * Do a local attach. We swap the consume and | |
1206 | * produce queues for the attacher and deliver | |
1207 | * an attach event. | |
1208 | */ | |
1209 | result = qp_notify_peer_local(true, *handle); | |
1210 | if (result < VMCI_SUCCESS) | |
1211 | goto error_keep_entry; | |
1212 | ||
1213 | my_produce_q = queue_pair_entry->consume_q; | |
1214 | my_consume_q = queue_pair_entry->produce_q; | |
1215 | goto out; | |
1216 | } | |
1217 | ||
1218 | result = VMCI_ERROR_ALREADY_EXISTS; | |
1219 | goto error_keep_entry; | |
1220 | } | |
1221 | ||
1222 | my_produce_q = qp_alloc_queue(produce_size, flags); | |
1223 | if (!my_produce_q) { | |
1224 | pr_warn("Error allocating pages for produce queue\n"); | |
1225 | result = VMCI_ERROR_NO_MEM; | |
1226 | goto error; | |
1227 | } | |
1228 | ||
1229 | my_consume_q = qp_alloc_queue(consume_size, flags); | |
1230 | if (!my_consume_q) { | |
1231 | pr_warn("Error allocating pages for consume queue\n"); | |
1232 | result = VMCI_ERROR_NO_MEM; | |
1233 | goto error; | |
1234 | } | |
1235 | ||
1236 | queue_pair_entry = qp_guest_endpoint_create(*handle, peer, flags, | |
1237 | produce_size, consume_size, | |
1238 | my_produce_q, my_consume_q); | |
1239 | if (!queue_pair_entry) { | |
1240 | pr_warn("Error allocating memory in %s\n", __func__); | |
1241 | result = VMCI_ERROR_NO_MEM; | |
1242 | goto error; | |
1243 | } | |
1244 | ||
1245 | result = qp_alloc_ppn_set(my_produce_q, num_produce_pages, my_consume_q, | |
1246 | num_consume_pages, | |
1247 | &queue_pair_entry->ppn_set); | |
1248 | if (result < VMCI_SUCCESS) { | |
1249 | pr_warn("qp_alloc_ppn_set failed\n"); | |
1250 | goto error; | |
1251 | } | |
1252 | ||
1253 | /* | |
1254 | * It's only necessary to notify the host if this queue pair will be | |
1255 | * attached to from another context. | |
1256 | */ | |
1257 | if (queue_pair_entry->qp.flags & VMCI_QPFLAG_LOCAL) { | |
1258 | /* Local create case. */ | |
1259 | u32 context_id = vmci_get_context_id(); | |
1260 | ||
1261 | /* | |
1262 | * Enforce similar checks on local queue pairs as we | |
1263 | * do for regular ones. The handle's context must | |
1264 | * match the creator or attacher context id (here they | |
1265 | * are both the current context id) and the | |
1266 | * attach-only flag cannot exist during create. We | |
1267 | * also ensure specified peer is this context or an | |
1268 | * invalid one. | |
1269 | */ | |
1270 | if (queue_pair_entry->qp.handle.context != context_id || | |
1271 | (queue_pair_entry->qp.peer != VMCI_INVALID_ID && | |
1272 | queue_pair_entry->qp.peer != context_id)) { | |
1273 | result = VMCI_ERROR_NO_ACCESS; | |
1274 | goto error; | |
1275 | } | |
1276 | ||
1277 | if (queue_pair_entry->qp.flags & VMCI_QPFLAG_ATTACH_ONLY) { | |
1278 | result = VMCI_ERROR_NOT_FOUND; | |
1279 | goto error; | |
1280 | } | |
1281 | } else { | |
1282 | result = qp_alloc_hypercall(queue_pair_entry); | |
1283 | if (result < VMCI_SUCCESS) { | |
1284 | pr_warn("qp_alloc_hypercall result = %d\n", result); | |
1285 | goto error; | |
1286 | } | |
1287 | } | |
1288 | ||
1289 | qp_init_queue_mutex((struct vmci_queue *)my_produce_q, | |
1290 | (struct vmci_queue *)my_consume_q); | |
1291 | ||
1292 | qp_list_add_entry(&qp_guest_endpoints, &queue_pair_entry->qp); | |
1293 | ||
1294 | out: | |
1295 | queue_pair_entry->qp.ref_count++; | |
1296 | *handle = queue_pair_entry->qp.handle; | |
1297 | *produce_q = (struct vmci_queue *)my_produce_q; | |
1298 | *consume_q = (struct vmci_queue *)my_consume_q; | |
1299 | ||
1300 | /* | |
1301 | * We should initialize the queue pair header pages on a local | |
1302 | * queue pair create. For non-local queue pairs, the | |
1303 | * hypervisor initializes the header pages in the create step. | |
1304 | */ | |
1305 | if ((queue_pair_entry->qp.flags & VMCI_QPFLAG_LOCAL) && | |
1306 | queue_pair_entry->qp.ref_count == 1) { | |
1307 | vmci_q_header_init((*produce_q)->q_header, *handle); | |
1308 | vmci_q_header_init((*consume_q)->q_header, *handle); | |
1309 | } | |
1310 | ||
1311 | mutex_unlock(&qp_guest_endpoints.mutex); | |
1312 | ||
1313 | return VMCI_SUCCESS; | |
1314 | ||
1315 | error: | |
1316 | mutex_unlock(&qp_guest_endpoints.mutex); | |
1317 | if (queue_pair_entry) { | |
1318 | /* The queues will be freed inside the destroy routine. */ | |
1319 | qp_guest_endpoint_destroy(queue_pair_entry); | |
1320 | } else { | |
1321 | qp_free_queue(my_produce_q, produce_size); | |
1322 | qp_free_queue(my_consume_q, consume_size); | |
1323 | } | |
1324 | return result; | |
1325 | ||
1326 | error_keep_entry: | |
1327 | /* This path should only be used when an existing entry was found. */ | |
1328 | mutex_unlock(&qp_guest_endpoints.mutex); | |
1329 | return result; | |
1330 | } | |
1331 | ||
1332 | /* | |
1333 | * The first endpoint issuing a queue pair allocation will create the state | |
1334 | * of the queue pair in the queue pair broker. | |
1335 | * | |
1336 | * If the creator is a guest, it will associate a VMX virtual address range | |
1337 | * with the queue pair as specified by the page_store. For compatibility with | |
1338 | * older VMX'en, that would use a separate step to set the VMX virtual | |
1339 | * address range, the virtual address range can be registered later using | |
1340 | * vmci_qp_broker_set_page_store. In that case, a page_store of NULL should be | |
1341 | * used. | |
1342 | * | |
1343 | * If the creator is the host, a page_store of NULL should be used as well, | |
1344 | * since the host is not able to supply a page store for the queue pair. | |
1345 | * | |
1346 | * For older VMX and host callers, the queue pair will be created in the | |
1347 | * VMCIQPB_CREATED_NO_MEM state, and for current VMX callers, it will be | |
1348 | * created in VMCOQPB_CREATED_MEM state. | |
1349 | */ | |
1350 | static int qp_broker_create(struct vmci_handle handle, | |
1351 | u32 peer, | |
1352 | u32 flags, | |
1353 | u32 priv_flags, | |
1354 | u64 produce_size, | |
1355 | u64 consume_size, | |
1356 | struct vmci_qp_page_store *page_store, | |
1357 | struct vmci_ctx *context, | |
1358 | vmci_event_release_cb wakeup_cb, | |
1359 | void *client_data, struct qp_broker_entry **ent) | |
1360 | { | |
1361 | struct qp_broker_entry *entry = NULL; | |
1362 | const u32 context_id = vmci_ctx_get_id(context); | |
1363 | bool is_local = flags & VMCI_QPFLAG_LOCAL; | |
1364 | int result; | |
1365 | u64 guest_produce_size; | |
1366 | u64 guest_consume_size; | |
1367 | ||
1368 | /* Do not create if the caller asked not to. */ | |
1369 | if (flags & VMCI_QPFLAG_ATTACH_ONLY) | |
1370 | return VMCI_ERROR_NOT_FOUND; | |
1371 | ||
1372 | /* | |
1373 | * Creator's context ID should match handle's context ID or the creator | |
1374 | * must allow the context in handle's context ID as the "peer". | |
1375 | */ | |
1376 | if (handle.context != context_id && handle.context != peer) | |
1377 | return VMCI_ERROR_NO_ACCESS; | |
1378 | ||
1379 | if (VMCI_CONTEXT_IS_VM(context_id) && VMCI_CONTEXT_IS_VM(peer)) | |
1380 | return VMCI_ERROR_DST_UNREACHABLE; | |
1381 | ||
1382 | /* | |
1383 | * Creator's context ID for local queue pairs should match the | |
1384 | * peer, if a peer is specified. | |
1385 | */ | |
1386 | if (is_local && peer != VMCI_INVALID_ID && context_id != peer) | |
1387 | return VMCI_ERROR_NO_ACCESS; | |
1388 | ||
1389 | entry = kzalloc(sizeof(*entry), GFP_ATOMIC); | |
1390 | if (!entry) | |
1391 | return VMCI_ERROR_NO_MEM; | |
1392 | ||
1393 | if (vmci_ctx_get_id(context) == VMCI_HOST_CONTEXT_ID && !is_local) { | |
1394 | /* | |
1395 | * The queue pair broker entry stores values from the guest | |
1396 | * point of view, so a creating host side endpoint should swap | |
1397 | * produce and consume values -- unless it is a local queue | |
1398 | * pair, in which case no swapping is necessary, since the local | |
1399 | * attacher will swap queues. | |
1400 | */ | |
1401 | ||
1402 | guest_produce_size = consume_size; | |
1403 | guest_consume_size = produce_size; | |
1404 | } else { | |
1405 | guest_produce_size = produce_size; | |
1406 | guest_consume_size = consume_size; | |
1407 | } | |
1408 | ||
1409 | entry->qp.handle = handle; | |
1410 | entry->qp.peer = peer; | |
1411 | entry->qp.flags = flags; | |
1412 | entry->qp.produce_size = guest_produce_size; | |
1413 | entry->qp.consume_size = guest_consume_size; | |
1414 | entry->qp.ref_count = 1; | |
1415 | entry->create_id = context_id; | |
1416 | entry->attach_id = VMCI_INVALID_ID; | |
1417 | entry->state = VMCIQPB_NEW; | |
1418 | entry->require_trusted_attach = | |
1419 | !!(context->priv_flags & VMCI_PRIVILEGE_FLAG_RESTRICTED); | |
1420 | entry->created_by_trusted = | |
1421 | !!(priv_flags & VMCI_PRIVILEGE_FLAG_TRUSTED); | |
1422 | entry->vmci_page_files = false; | |
1423 | entry->wakeup_cb = wakeup_cb; | |
1424 | entry->client_data = client_data; | |
1425 | entry->produce_q = qp_host_alloc_queue(guest_produce_size); | |
1426 | if (entry->produce_q == NULL) { | |
1427 | result = VMCI_ERROR_NO_MEM; | |
1428 | goto error; | |
1429 | } | |
1430 | entry->consume_q = qp_host_alloc_queue(guest_consume_size); | |
1431 | if (entry->consume_q == NULL) { | |
1432 | result = VMCI_ERROR_NO_MEM; | |
1433 | goto error; | |
1434 | } | |
1435 | ||
1436 | qp_init_queue_mutex(entry->produce_q, entry->consume_q); | |
1437 | ||
1438 | INIT_LIST_HEAD(&entry->qp.list_item); | |
1439 | ||
1440 | if (is_local) { | |
1441 | u8 *tmp; | |
1442 | ||
1443 | entry->local_mem = kcalloc(QPE_NUM_PAGES(entry->qp), | |
1444 | PAGE_SIZE, GFP_KERNEL); | |
1445 | if (entry->local_mem == NULL) { | |
1446 | result = VMCI_ERROR_NO_MEM; | |
1447 | goto error; | |
1448 | } | |
1449 | entry->state = VMCIQPB_CREATED_MEM; | |
1450 | entry->produce_q->q_header = entry->local_mem; | |
1451 | tmp = (u8 *)entry->local_mem + PAGE_SIZE * | |
42281d20 | 1452 | (DIV_ROUND_UP(entry->qp.produce_size, PAGE_SIZE) + 1); |
06164d2b GZ |
1453 | entry->consume_q->q_header = (struct vmci_queue_header *)tmp; |
1454 | } else if (page_store) { | |
1455 | /* | |
1456 | * The VMX already initialized the queue pair headers, so no | |
1457 | * need for the kernel side to do that. | |
1458 | */ | |
1459 | result = qp_host_register_user_memory(page_store, | |
1460 | entry->produce_q, | |
1461 | entry->consume_q); | |
1462 | if (result < VMCI_SUCCESS) | |
1463 | goto error; | |
1464 | ||
1465 | entry->state = VMCIQPB_CREATED_MEM; | |
1466 | } else { | |
1467 | /* | |
1468 | * A create without a page_store may be either a host | |
1469 | * side create (in which case we are waiting for the | |
1470 | * guest side to supply the memory) or an old style | |
1471 | * queue pair create (in which case we will expect a | |
1472 | * set page store call as the next step). | |
1473 | */ | |
1474 | entry->state = VMCIQPB_CREATED_NO_MEM; | |
1475 | } | |
1476 | ||
1477 | qp_list_add_entry(&qp_broker_list, &entry->qp); | |
1478 | if (ent != NULL) | |
1479 | *ent = entry; | |
1480 | ||
1481 | /* Add to resource obj */ | |
1482 | result = vmci_resource_add(&entry->resource, | |
1483 | VMCI_RESOURCE_TYPE_QPAIR_HOST, | |
1484 | handle); | |
1485 | if (result != VMCI_SUCCESS) { | |
1486 | pr_warn("Failed to add new resource (handle=0x%x:0x%x), error: %d", | |
1487 | handle.context, handle.resource, result); | |
1488 | goto error; | |
1489 | } | |
1490 | ||
1491 | entry->qp.handle = vmci_resource_handle(&entry->resource); | |
1492 | if (is_local) { | |
1493 | vmci_q_header_init(entry->produce_q->q_header, | |
1494 | entry->qp.handle); | |
1495 | vmci_q_header_init(entry->consume_q->q_header, | |
1496 | entry->qp.handle); | |
1497 | } | |
1498 | ||
1499 | vmci_ctx_qp_create(context, entry->qp.handle); | |
1500 | ||
1501 | return VMCI_SUCCESS; | |
1502 | ||
1503 | error: | |
1504 | if (entry != NULL) { | |
1505 | qp_host_free_queue(entry->produce_q, guest_produce_size); | |
1506 | qp_host_free_queue(entry->consume_q, guest_consume_size); | |
1507 | kfree(entry); | |
1508 | } | |
1509 | ||
1510 | return result; | |
1511 | } | |
1512 | ||
1513 | /* | |
1514 | * Enqueues an event datagram to notify the peer VM attached to | |
1515 | * the given queue pair handle about attach/detach event by the | |
1516 | * given VM. Returns Payload size of datagram enqueued on | |
1517 | * success, error code otherwise. | |
1518 | */ | |
1519 | static int qp_notify_peer(bool attach, | |
1520 | struct vmci_handle handle, | |
1521 | u32 my_id, | |
1522 | u32 peer_id) | |
1523 | { | |
1524 | int rv; | |
1525 | struct vmci_event_qp ev; | |
1526 | ||
1527 | if (vmci_handle_is_invalid(handle) || my_id == VMCI_INVALID_ID || | |
1528 | peer_id == VMCI_INVALID_ID) | |
1529 | return VMCI_ERROR_INVALID_ARGS; | |
1530 | ||
1531 | /* | |
1532 | * In vmci_ctx_enqueue_datagram() we enforce the upper limit on | |
1533 | * number of pending events from the hypervisor to a given VM | |
1534 | * otherwise a rogue VM could do an arbitrary number of attach | |
1535 | * and detach operations causing memory pressure in the host | |
1536 | * kernel. | |
1537 | */ | |
1538 | ||
1539 | ev.msg.hdr.dst = vmci_make_handle(peer_id, VMCI_EVENT_HANDLER); | |
1540 | ev.msg.hdr.src = vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID, | |
1541 | VMCI_CONTEXT_RESOURCE_ID); | |
1542 | ev.msg.hdr.payload_size = sizeof(ev) - sizeof(ev.msg.hdr); | |
1543 | ev.msg.event_data.event = attach ? | |
1544 | VMCI_EVENT_QP_PEER_ATTACH : VMCI_EVENT_QP_PEER_DETACH; | |
1545 | ev.payload.handle = handle; | |
1546 | ev.payload.peer_id = my_id; | |
1547 | ||
1548 | rv = vmci_datagram_dispatch(VMCI_HYPERVISOR_CONTEXT_ID, | |
1549 | &ev.msg.hdr, false); | |
1550 | if (rv < VMCI_SUCCESS) | |
1551 | pr_warn("Failed to enqueue queue_pair %s event datagram for context (ID=0x%x)\n", | |
1552 | attach ? "ATTACH" : "DETACH", peer_id); | |
1553 | ||
1554 | return rv; | |
1555 | } | |
1556 | ||
1557 | /* | |
1558 | * The second endpoint issuing a queue pair allocation will attach to | |
1559 | * the queue pair registered with the queue pair broker. | |
1560 | * | |
1561 | * If the attacher is a guest, it will associate a VMX virtual address | |
1562 | * range with the queue pair as specified by the page_store. At this | |
1563 | * point, the already attach host endpoint may start using the queue | |
1564 | * pair, and an attach event is sent to it. For compatibility with | |
1565 | * older VMX'en, that used a separate step to set the VMX virtual | |
1566 | * address range, the virtual address range can be registered later | |
1567 | * using vmci_qp_broker_set_page_store. In that case, a page_store of | |
1568 | * NULL should be used, and the attach event will be generated once | |
1569 | * the actual page store has been set. | |
1570 | * | |
1571 | * If the attacher is the host, a page_store of NULL should be used as | |
1572 | * well, since the page store information is already set by the guest. | |
1573 | * | |
1574 | * For new VMX and host callers, the queue pair will be moved to the | |
1575 | * VMCIQPB_ATTACHED_MEM state, and for older VMX callers, it will be | |
1576 | * moved to the VMCOQPB_ATTACHED_NO_MEM state. | |
1577 | */ | |
1578 | static int qp_broker_attach(struct qp_broker_entry *entry, | |
1579 | u32 peer, | |
1580 | u32 flags, | |
1581 | u32 priv_flags, | |
1582 | u64 produce_size, | |
1583 | u64 consume_size, | |
1584 | struct vmci_qp_page_store *page_store, | |
1585 | struct vmci_ctx *context, | |
1586 | vmci_event_release_cb wakeup_cb, | |
1587 | void *client_data, | |
1588 | struct qp_broker_entry **ent) | |
1589 | { | |
1590 | const u32 context_id = vmci_ctx_get_id(context); | |
1591 | bool is_local = flags & VMCI_QPFLAG_LOCAL; | |
1592 | int result; | |
1593 | ||
1594 | if (entry->state != VMCIQPB_CREATED_NO_MEM && | |
1595 | entry->state != VMCIQPB_CREATED_MEM) | |
1596 | return VMCI_ERROR_UNAVAILABLE; | |
1597 | ||
1598 | if (is_local) { | |
1599 | if (!(entry->qp.flags & VMCI_QPFLAG_LOCAL) || | |
1600 | context_id != entry->create_id) { | |
1601 | return VMCI_ERROR_INVALID_ARGS; | |
1602 | } | |
1603 | } else if (context_id == entry->create_id || | |
1604 | context_id == entry->attach_id) { | |
1605 | return VMCI_ERROR_ALREADY_EXISTS; | |
1606 | } | |
1607 | ||
1608 | if (VMCI_CONTEXT_IS_VM(context_id) && | |
1609 | VMCI_CONTEXT_IS_VM(entry->create_id)) | |
1610 | return VMCI_ERROR_DST_UNREACHABLE; | |
1611 | ||
1612 | /* | |
1613 | * If we are attaching from a restricted context then the queuepair | |
1614 | * must have been created by a trusted endpoint. | |
1615 | */ | |
1616 | if ((context->priv_flags & VMCI_PRIVILEGE_FLAG_RESTRICTED) && | |
1617 | !entry->created_by_trusted) | |
1618 | return VMCI_ERROR_NO_ACCESS; | |
1619 | ||
1620 | /* | |
1621 | * If we are attaching to a queuepair that was created by a restricted | |
1622 | * context then we must be trusted. | |
1623 | */ | |
1624 | if (entry->require_trusted_attach && | |
1625 | (!(priv_flags & VMCI_PRIVILEGE_FLAG_TRUSTED))) | |
1626 | return VMCI_ERROR_NO_ACCESS; | |
1627 | ||
1628 | /* | |
1629 | * If the creator specifies VMCI_INVALID_ID in "peer" field, access | |
1630 | * control check is not performed. | |
1631 | */ | |
1632 | if (entry->qp.peer != VMCI_INVALID_ID && entry->qp.peer != context_id) | |
1633 | return VMCI_ERROR_NO_ACCESS; | |
1634 | ||
1635 | if (entry->create_id == VMCI_HOST_CONTEXT_ID) { | |
1636 | /* | |
1637 | * Do not attach if the caller doesn't support Host Queue Pairs | |
1638 | * and a host created this queue pair. | |
1639 | */ | |
1640 | ||
1641 | if (!vmci_ctx_supports_host_qp(context)) | |
1642 | return VMCI_ERROR_INVALID_RESOURCE; | |
1643 | ||
1644 | } else if (context_id == VMCI_HOST_CONTEXT_ID) { | |
1645 | struct vmci_ctx *create_context; | |
1646 | bool supports_host_qp; | |
1647 | ||
1648 | /* | |
1649 | * Do not attach a host to a user created queue pair if that | |
1650 | * user doesn't support host queue pair end points. | |
1651 | */ | |
1652 | ||
1653 | create_context = vmci_ctx_get(entry->create_id); | |
1654 | supports_host_qp = vmci_ctx_supports_host_qp(create_context); | |
1655 | vmci_ctx_put(create_context); | |
1656 | ||
1657 | if (!supports_host_qp) | |
1658 | return VMCI_ERROR_INVALID_RESOURCE; | |
1659 | } | |
1660 | ||
1661 | if ((entry->qp.flags & ~VMCI_QP_ASYMM) != (flags & ~VMCI_QP_ASYMM_PEER)) | |
1662 | return VMCI_ERROR_QUEUEPAIR_MISMATCH; | |
1663 | ||
1664 | if (context_id != VMCI_HOST_CONTEXT_ID) { | |
1665 | /* | |
1666 | * The queue pair broker entry stores values from the guest | |
1667 | * point of view, so an attaching guest should match the values | |
1668 | * stored in the entry. | |
1669 | */ | |
1670 | ||
1671 | if (entry->qp.produce_size != produce_size || | |
1672 | entry->qp.consume_size != consume_size) { | |
1673 | return VMCI_ERROR_QUEUEPAIR_MISMATCH; | |
1674 | } | |
1675 | } else if (entry->qp.produce_size != consume_size || | |
1676 | entry->qp.consume_size != produce_size) { | |
1677 | return VMCI_ERROR_QUEUEPAIR_MISMATCH; | |
1678 | } | |
1679 | ||
1680 | if (context_id != VMCI_HOST_CONTEXT_ID) { | |
1681 | /* | |
1682 | * If a guest attached to a queue pair, it will supply | |
1683 | * the backing memory. If this is a pre NOVMVM vmx, | |
1684 | * the backing memory will be supplied by calling | |
1685 | * vmci_qp_broker_set_page_store() following the | |
1686 | * return of the vmci_qp_broker_alloc() call. If it is | |
1687 | * a vmx of version NOVMVM or later, the page store | |
1688 | * must be supplied as part of the | |
1689 | * vmci_qp_broker_alloc call. Under all circumstances | |
1690 | * must the initially created queue pair not have any | |
1691 | * memory associated with it already. | |
1692 | */ | |
1693 | ||
1694 | if (entry->state != VMCIQPB_CREATED_NO_MEM) | |
1695 | return VMCI_ERROR_INVALID_ARGS; | |
1696 | ||
1697 | if (page_store != NULL) { | |
1698 | /* | |
1699 | * Patch up host state to point to guest | |
1700 | * supplied memory. The VMX already | |
1701 | * initialized the queue pair headers, so no | |
1702 | * need for the kernel side to do that. | |
1703 | */ | |
1704 | ||
1705 | result = qp_host_register_user_memory(page_store, | |
1706 | entry->produce_q, | |
1707 | entry->consume_q); | |
1708 | if (result < VMCI_SUCCESS) | |
1709 | return result; | |
1710 | ||
06164d2b GZ |
1711 | entry->state = VMCIQPB_ATTACHED_MEM; |
1712 | } else { | |
1713 | entry->state = VMCIQPB_ATTACHED_NO_MEM; | |
1714 | } | |
1715 | } else if (entry->state == VMCIQPB_CREATED_NO_MEM) { | |
1716 | /* | |
1717 | * The host side is attempting to attach to a queue | |
1718 | * pair that doesn't have any memory associated with | |
1719 | * it. This must be a pre NOVMVM vmx that hasn't set | |
1720 | * the page store information yet, or a quiesced VM. | |
1721 | */ | |
1722 | ||
1723 | return VMCI_ERROR_UNAVAILABLE; | |
1724 | } else { | |
06164d2b GZ |
1725 | /* The host side has successfully attached to a queue pair. */ |
1726 | entry->state = VMCIQPB_ATTACHED_MEM; | |
1727 | } | |
1728 | ||
1729 | if (entry->state == VMCIQPB_ATTACHED_MEM) { | |
1730 | result = | |
1731 | qp_notify_peer(true, entry->qp.handle, context_id, | |
1732 | entry->create_id); | |
1733 | if (result < VMCI_SUCCESS) | |
1734 | pr_warn("Failed to notify peer (ID=0x%x) of attach to queue pair (handle=0x%x:0x%x)\n", | |
1735 | entry->create_id, entry->qp.handle.context, | |
1736 | entry->qp.handle.resource); | |
1737 | } | |
1738 | ||
1739 | entry->attach_id = context_id; | |
1740 | entry->qp.ref_count++; | |
1741 | if (wakeup_cb) { | |
1742 | entry->wakeup_cb = wakeup_cb; | |
1743 | entry->client_data = client_data; | |
1744 | } | |
1745 | ||
1746 | /* | |
1747 | * When attaching to local queue pairs, the context already has | |
1748 | * an entry tracking the queue pair, so don't add another one. | |
1749 | */ | |
1750 | if (!is_local) | |
1751 | vmci_ctx_qp_create(context, entry->qp.handle); | |
1752 | ||
1753 | if (ent != NULL) | |
1754 | *ent = entry; | |
1755 | ||
1756 | return VMCI_SUCCESS; | |
1757 | } | |
1758 | ||
1759 | /* | |
1760 | * queue_pair_Alloc for use when setting up queue pair endpoints | |
1761 | * on the host. | |
1762 | */ | |
1763 | static int qp_broker_alloc(struct vmci_handle handle, | |
1764 | u32 peer, | |
1765 | u32 flags, | |
1766 | u32 priv_flags, | |
1767 | u64 produce_size, | |
1768 | u64 consume_size, | |
1769 | struct vmci_qp_page_store *page_store, | |
1770 | struct vmci_ctx *context, | |
1771 | vmci_event_release_cb wakeup_cb, | |
1772 | void *client_data, | |
1773 | struct qp_broker_entry **ent, | |
1774 | bool *swap) | |
1775 | { | |
1776 | const u32 context_id = vmci_ctx_get_id(context); | |
1777 | bool create; | |
1778 | struct qp_broker_entry *entry = NULL; | |
1779 | bool is_local = flags & VMCI_QPFLAG_LOCAL; | |
1780 | int result; | |
1781 | ||
1782 | if (vmci_handle_is_invalid(handle) || | |
1783 | (flags & ~VMCI_QP_ALL_FLAGS) || is_local || | |
1784 | !(produce_size || consume_size) || | |
1785 | !context || context_id == VMCI_INVALID_ID || | |
1786 | handle.context == VMCI_INVALID_ID) { | |
1787 | return VMCI_ERROR_INVALID_ARGS; | |
1788 | } | |
1789 | ||
1790 | if (page_store && !VMCI_QP_PAGESTORE_IS_WELLFORMED(page_store)) | |
1791 | return VMCI_ERROR_INVALID_ARGS; | |
1792 | ||
1793 | /* | |
1794 | * In the initial argument check, we ensure that non-vmkernel hosts | |
1795 | * are not allowed to create local queue pairs. | |
1796 | */ | |
1797 | ||
1798 | mutex_lock(&qp_broker_list.mutex); | |
1799 | ||
1800 | if (!is_local && vmci_ctx_qp_exists(context, handle)) { | |
1801 | pr_devel("Context (ID=0x%x) already attached to queue pair (handle=0x%x:0x%x)\n", | |
1802 | context_id, handle.context, handle.resource); | |
1803 | mutex_unlock(&qp_broker_list.mutex); | |
1804 | return VMCI_ERROR_ALREADY_EXISTS; | |
1805 | } | |
1806 | ||
1807 | if (handle.resource != VMCI_INVALID_ID) | |
1808 | entry = qp_broker_handle_to_entry(handle); | |
1809 | ||
1810 | if (!entry) { | |
1811 | create = true; | |
1812 | result = | |
1813 | qp_broker_create(handle, peer, flags, priv_flags, | |
1814 | produce_size, consume_size, page_store, | |
1815 | context, wakeup_cb, client_data, ent); | |
1816 | } else { | |
1817 | create = false; | |
1818 | result = | |
1819 | qp_broker_attach(entry, peer, flags, priv_flags, | |
1820 | produce_size, consume_size, page_store, | |
1821 | context, wakeup_cb, client_data, ent); | |
1822 | } | |
1823 | ||
1824 | mutex_unlock(&qp_broker_list.mutex); | |
1825 | ||
1826 | if (swap) | |
1827 | *swap = (context_id == VMCI_HOST_CONTEXT_ID) && | |
1828 | !(create && is_local); | |
1829 | ||
1830 | return result; | |
1831 | } | |
1832 | ||
1833 | /* | |
1834 | * This function implements the kernel API for allocating a queue | |
1835 | * pair. | |
1836 | */ | |
1837 | static int qp_alloc_host_work(struct vmci_handle *handle, | |
1838 | struct vmci_queue **produce_q, | |
1839 | u64 produce_size, | |
1840 | struct vmci_queue **consume_q, | |
1841 | u64 consume_size, | |
1842 | u32 peer, | |
1843 | u32 flags, | |
1844 | u32 priv_flags, | |
1845 | vmci_event_release_cb wakeup_cb, | |
1846 | void *client_data) | |
1847 | { | |
1848 | struct vmci_handle new_handle; | |
1849 | struct vmci_ctx *context; | |
1850 | struct qp_broker_entry *entry; | |
1851 | int result; | |
1852 | bool swap; | |
1853 | ||
1854 | if (vmci_handle_is_invalid(*handle)) { | |
1855 | new_handle = vmci_make_handle( | |
1856 | VMCI_HOST_CONTEXT_ID, VMCI_INVALID_ID); | |
1857 | } else | |
1858 | new_handle = *handle; | |
1859 | ||
1860 | context = vmci_ctx_get(VMCI_HOST_CONTEXT_ID); | |
1861 | entry = NULL; | |
1862 | result = | |
1863 | qp_broker_alloc(new_handle, peer, flags, priv_flags, | |
1864 | produce_size, consume_size, NULL, context, | |
1865 | wakeup_cb, client_data, &entry, &swap); | |
1866 | if (result == VMCI_SUCCESS) { | |
1867 | if (swap) { | |
1868 | /* | |
1869 | * If this is a local queue pair, the attacher | |
1870 | * will swap around produce and consume | |
1871 | * queues. | |
1872 | */ | |
1873 | ||
1874 | *produce_q = entry->consume_q; | |
1875 | *consume_q = entry->produce_q; | |
1876 | } else { | |
1877 | *produce_q = entry->produce_q; | |
1878 | *consume_q = entry->consume_q; | |
1879 | } | |
1880 | ||
1881 | *handle = vmci_resource_handle(&entry->resource); | |
1882 | } else { | |
1883 | *handle = VMCI_INVALID_HANDLE; | |
1884 | pr_devel("queue pair broker failed to alloc (result=%d)\n", | |
1885 | result); | |
1886 | } | |
1887 | vmci_ctx_put(context); | |
1888 | return result; | |
1889 | } | |
1890 | ||
1891 | /* | |
1892 | * Allocates a VMCI queue_pair. Only checks validity of input | |
1893 | * arguments. The real work is done in the host or guest | |
1894 | * specific function. | |
1895 | */ | |
1896 | int vmci_qp_alloc(struct vmci_handle *handle, | |
1897 | struct vmci_queue **produce_q, | |
1898 | u64 produce_size, | |
1899 | struct vmci_queue **consume_q, | |
1900 | u64 consume_size, | |
1901 | u32 peer, | |
1902 | u32 flags, | |
1903 | u32 priv_flags, | |
1904 | bool guest_endpoint, | |
1905 | vmci_event_release_cb wakeup_cb, | |
1906 | void *client_data) | |
1907 | { | |
1908 | if (!handle || !produce_q || !consume_q || | |
1909 | (!produce_size && !consume_size) || (flags & ~VMCI_QP_ALL_FLAGS)) | |
1910 | return VMCI_ERROR_INVALID_ARGS; | |
1911 | ||
1912 | if (guest_endpoint) { | |
1913 | return qp_alloc_guest_work(handle, produce_q, | |
1914 | produce_size, consume_q, | |
1915 | consume_size, peer, | |
1916 | flags, priv_flags); | |
1917 | } else { | |
1918 | return qp_alloc_host_work(handle, produce_q, | |
1919 | produce_size, consume_q, | |
1920 | consume_size, peer, flags, | |
1921 | priv_flags, wakeup_cb, client_data); | |
1922 | } | |
1923 | } | |
1924 | ||
1925 | /* | |
1926 | * This function implements the host kernel API for detaching from | |
1927 | * a queue pair. | |
1928 | */ | |
1929 | static int qp_detatch_host_work(struct vmci_handle handle) | |
1930 | { | |
1931 | int result; | |
1932 | struct vmci_ctx *context; | |
1933 | ||
1934 | context = vmci_ctx_get(VMCI_HOST_CONTEXT_ID); | |
1935 | ||
1936 | result = vmci_qp_broker_detach(handle, context); | |
1937 | ||
1938 | vmci_ctx_put(context); | |
1939 | return result; | |
1940 | } | |
1941 | ||
1942 | /* | |
1943 | * Detaches from a VMCI queue_pair. Only checks validity of input argument. | |
1944 | * Real work is done in the host or guest specific function. | |
1945 | */ | |
1946 | static int qp_detatch(struct vmci_handle handle, bool guest_endpoint) | |
1947 | { | |
1948 | if (vmci_handle_is_invalid(handle)) | |
1949 | return VMCI_ERROR_INVALID_ARGS; | |
1950 | ||
1951 | if (guest_endpoint) | |
1952 | return qp_detatch_guest_work(handle); | |
1953 | else | |
1954 | return qp_detatch_host_work(handle); | |
1955 | } | |
1956 | ||
1957 | /* | |
1958 | * Returns the entry from the head of the list. Assumes that the list is | |
1959 | * locked. | |
1960 | */ | |
1961 | static struct qp_entry *qp_list_get_head(struct qp_list *qp_list) | |
1962 | { | |
1963 | if (!list_empty(&qp_list->head)) { | |
1964 | struct qp_entry *entry = | |
1965 | list_first_entry(&qp_list->head, struct qp_entry, | |
1966 | list_item); | |
1967 | return entry; | |
1968 | } | |
1969 | ||
1970 | return NULL; | |
1971 | } | |
1972 | ||
1973 | void vmci_qp_broker_exit(void) | |
1974 | { | |
1975 | struct qp_entry *entry; | |
1976 | struct qp_broker_entry *be; | |
1977 | ||
1978 | mutex_lock(&qp_broker_list.mutex); | |
1979 | ||
1980 | while ((entry = qp_list_get_head(&qp_broker_list))) { | |
1981 | be = (struct qp_broker_entry *)entry; | |
1982 | ||
1983 | qp_list_remove_entry(&qp_broker_list, entry); | |
1984 | kfree(be); | |
1985 | } | |
1986 | ||
1987 | mutex_unlock(&qp_broker_list.mutex); | |
1988 | } | |
1989 | ||
1990 | /* | |
1991 | * Requests that a queue pair be allocated with the VMCI queue | |
1992 | * pair broker. Allocates a queue pair entry if one does not | |
1993 | * exist. Attaches to one if it exists, and retrieves the page | |
1994 | * files backing that queue_pair. Assumes that the queue pair | |
1995 | * broker lock is held. | |
1996 | */ | |
1997 | int vmci_qp_broker_alloc(struct vmci_handle handle, | |
1998 | u32 peer, | |
1999 | u32 flags, | |
2000 | u32 priv_flags, | |
2001 | u64 produce_size, | |
2002 | u64 consume_size, | |
2003 | struct vmci_qp_page_store *page_store, | |
2004 | struct vmci_ctx *context) | |
2005 | { | |
2006 | return qp_broker_alloc(handle, peer, flags, priv_flags, | |
2007 | produce_size, consume_size, | |
2008 | page_store, context, NULL, NULL, NULL, NULL); | |
2009 | } | |
2010 | ||
2011 | /* | |
2012 | * VMX'en with versions lower than VMCI_VERSION_NOVMVM use a separate | |
2013 | * step to add the UVAs of the VMX mapping of the queue pair. This function | |
2014 | * provides backwards compatibility with such VMX'en, and takes care of | |
2015 | * registering the page store for a queue pair previously allocated by the | |
2016 | * VMX during create or attach. This function will move the queue pair state | |
2017 | * to either from VMCIQBP_CREATED_NO_MEM to VMCIQBP_CREATED_MEM or | |
2018 | * VMCIQBP_ATTACHED_NO_MEM to VMCIQBP_ATTACHED_MEM. If moving to the | |
2019 | * attached state with memory, the queue pair is ready to be used by the | |
2020 | * host peer, and an attached event will be generated. | |
2021 | * | |
2022 | * Assumes that the queue pair broker lock is held. | |
2023 | * | |
2024 | * This function is only used by the hosted platform, since there is no | |
2025 | * issue with backwards compatibility for vmkernel. | |
2026 | */ | |
2027 | int vmci_qp_broker_set_page_store(struct vmci_handle handle, | |
2028 | u64 produce_uva, | |
2029 | u64 consume_uva, | |
2030 | struct vmci_ctx *context) | |
2031 | { | |
2032 | struct qp_broker_entry *entry; | |
2033 | int result; | |
2034 | const u32 context_id = vmci_ctx_get_id(context); | |
2035 | ||
2036 | if (vmci_handle_is_invalid(handle) || !context || | |
2037 | context_id == VMCI_INVALID_ID) | |
2038 | return VMCI_ERROR_INVALID_ARGS; | |
2039 | ||
2040 | /* | |
2041 | * We only support guest to host queue pairs, so the VMX must | |
2042 | * supply UVAs for the mapped page files. | |
2043 | */ | |
2044 | ||
2045 | if (produce_uva == 0 || consume_uva == 0) | |
2046 | return VMCI_ERROR_INVALID_ARGS; | |
2047 | ||
2048 | mutex_lock(&qp_broker_list.mutex); | |
2049 | ||
2050 | if (!vmci_ctx_qp_exists(context, handle)) { | |
2051 | pr_warn("Context (ID=0x%x) not attached to queue pair (handle=0x%x:0x%x)\n", | |
2052 | context_id, handle.context, handle.resource); | |
2053 | result = VMCI_ERROR_NOT_FOUND; | |
2054 | goto out; | |
2055 | } | |
2056 | ||
2057 | entry = qp_broker_handle_to_entry(handle); | |
2058 | if (!entry) { | |
2059 | result = VMCI_ERROR_NOT_FOUND; | |
2060 | goto out; | |
2061 | } | |
2062 | ||
2063 | /* | |
2064 | * If I'm the owner then I can set the page store. | |
2065 | * | |
2066 | * Or, if a host created the queue_pair and I'm the attached peer | |
2067 | * then I can set the page store. | |
2068 | */ | |
2069 | if (entry->create_id != context_id && | |
2070 | (entry->create_id != VMCI_HOST_CONTEXT_ID || | |
2071 | entry->attach_id != context_id)) { | |
2072 | result = VMCI_ERROR_QUEUEPAIR_NOTOWNER; | |
2073 | goto out; | |
2074 | } | |
2075 | ||
2076 | if (entry->state != VMCIQPB_CREATED_NO_MEM && | |
2077 | entry->state != VMCIQPB_ATTACHED_NO_MEM) { | |
2078 | result = VMCI_ERROR_UNAVAILABLE; | |
2079 | goto out; | |
2080 | } | |
2081 | ||
2082 | result = qp_host_get_user_memory(produce_uva, consume_uva, | |
2083 | entry->produce_q, entry->consume_q); | |
2084 | if (result < VMCI_SUCCESS) | |
2085 | goto out; | |
2086 | ||
2087 | result = qp_host_map_queues(entry->produce_q, entry->consume_q); | |
2088 | if (result < VMCI_SUCCESS) { | |
2089 | qp_host_unregister_user_memory(entry->produce_q, | |
2090 | entry->consume_q); | |
2091 | goto out; | |
2092 | } | |
2093 | ||
2094 | if (entry->state == VMCIQPB_CREATED_NO_MEM) | |
2095 | entry->state = VMCIQPB_CREATED_MEM; | |
2096 | else | |
2097 | entry->state = VMCIQPB_ATTACHED_MEM; | |
2098 | ||
2099 | entry->vmci_page_files = true; | |
2100 | ||
2101 | if (entry->state == VMCIQPB_ATTACHED_MEM) { | |
2102 | result = | |
2103 | qp_notify_peer(true, handle, context_id, entry->create_id); | |
2104 | if (result < VMCI_SUCCESS) { | |
2105 | pr_warn("Failed to notify peer (ID=0x%x) of attach to queue pair (handle=0x%x:0x%x)\n", | |
2106 | entry->create_id, entry->qp.handle.context, | |
2107 | entry->qp.handle.resource); | |
2108 | } | |
2109 | } | |
2110 | ||
2111 | result = VMCI_SUCCESS; | |
2112 | out: | |
2113 | mutex_unlock(&qp_broker_list.mutex); | |
2114 | return result; | |
2115 | } | |
2116 | ||
2117 | /* | |
2118 | * Resets saved queue headers for the given QP broker | |
2119 | * entry. Should be used when guest memory becomes available | |
2120 | * again, or the guest detaches. | |
2121 | */ | |
2122 | static void qp_reset_saved_headers(struct qp_broker_entry *entry) | |
2123 | { | |
2124 | entry->produce_q->saved_header = NULL; | |
2125 | entry->consume_q->saved_header = NULL; | |
2126 | } | |
2127 | ||
2128 | /* | |
2129 | * The main entry point for detaching from a queue pair registered with the | |
2130 | * queue pair broker. If more than one endpoint is attached to the queue | |
2131 | * pair, the first endpoint will mainly decrement a reference count and | |
2132 | * generate a notification to its peer. The last endpoint will clean up | |
2133 | * the queue pair state registered with the broker. | |
2134 | * | |
2135 | * When a guest endpoint detaches, it will unmap and unregister the guest | |
2136 | * memory backing the queue pair. If the host is still attached, it will | |
2137 | * no longer be able to access the queue pair content. | |
2138 | * | |
2139 | * If the queue pair is already in a state where there is no memory | |
2140 | * registered for the queue pair (any *_NO_MEM state), it will transition to | |
2141 | * the VMCIQPB_SHUTDOWN_NO_MEM state. This will also happen, if a guest | |
2142 | * endpoint is the first of two endpoints to detach. If the host endpoint is | |
2143 | * the first out of two to detach, the queue pair will move to the | |
2144 | * VMCIQPB_SHUTDOWN_MEM state. | |
2145 | */ | |
2146 | int vmci_qp_broker_detach(struct vmci_handle handle, struct vmci_ctx *context) | |
2147 | { | |
2148 | struct qp_broker_entry *entry; | |
2149 | const u32 context_id = vmci_ctx_get_id(context); | |
2150 | u32 peer_id; | |
2151 | bool is_local = false; | |
2152 | int result; | |
2153 | ||
2154 | if (vmci_handle_is_invalid(handle) || !context || | |
2155 | context_id == VMCI_INVALID_ID) { | |
2156 | return VMCI_ERROR_INVALID_ARGS; | |
2157 | } | |
2158 | ||
2159 | mutex_lock(&qp_broker_list.mutex); | |
2160 | ||
2161 | if (!vmci_ctx_qp_exists(context, handle)) { | |
2162 | pr_devel("Context (ID=0x%x) not attached to queue pair (handle=0x%x:0x%x)\n", | |
2163 | context_id, handle.context, handle.resource); | |
2164 | result = VMCI_ERROR_NOT_FOUND; | |
2165 | goto out; | |
2166 | } | |
2167 | ||
2168 | entry = qp_broker_handle_to_entry(handle); | |
2169 | if (!entry) { | |
2170 | pr_devel("Context (ID=0x%x) reports being attached to queue pair(handle=0x%x:0x%x) that isn't present in broker\n", | |
2171 | context_id, handle.context, handle.resource); | |
2172 | result = VMCI_ERROR_NOT_FOUND; | |
2173 | goto out; | |
2174 | } | |
2175 | ||
2176 | if (context_id != entry->create_id && context_id != entry->attach_id) { | |
2177 | result = VMCI_ERROR_QUEUEPAIR_NOTATTACHED; | |
2178 | goto out; | |
2179 | } | |
2180 | ||
2181 | if (context_id == entry->create_id) { | |
2182 | peer_id = entry->attach_id; | |
2183 | entry->create_id = VMCI_INVALID_ID; | |
2184 | } else { | |
2185 | peer_id = entry->create_id; | |
2186 | entry->attach_id = VMCI_INVALID_ID; | |
2187 | } | |
2188 | entry->qp.ref_count--; | |
2189 | ||
2190 | is_local = entry->qp.flags & VMCI_QPFLAG_LOCAL; | |
2191 | ||
2192 | if (context_id != VMCI_HOST_CONTEXT_ID) { | |
2193 | bool headers_mapped; | |
2194 | ||
2195 | /* | |
2196 | * Pre NOVMVM vmx'en may detach from a queue pair | |
2197 | * before setting the page store, and in that case | |
2198 | * there is no user memory to detach from. Also, more | |
2199 | * recent VMX'en may detach from a queue pair in the | |
2200 | * quiesced state. | |
2201 | */ | |
2202 | ||
2203 | qp_acquire_queue_mutex(entry->produce_q); | |
2204 | headers_mapped = entry->produce_q->q_header || | |
2205 | entry->consume_q->q_header; | |
2206 | if (QPBROKERSTATE_HAS_MEM(entry)) { | |
2207 | result = | |
2208 | qp_host_unmap_queues(INVALID_VMCI_GUEST_MEM_ID, | |
2209 | entry->produce_q, | |
2210 | entry->consume_q); | |
2211 | if (result < VMCI_SUCCESS) | |
2212 | pr_warn("Failed to unmap queue headers for queue pair (handle=0x%x:0x%x,result=%d)\n", | |
2213 | handle.context, handle.resource, | |
2214 | result); | |
2215 | ||
2216 | if (entry->vmci_page_files) | |
2217 | qp_host_unregister_user_memory(entry->produce_q, | |
2218 | entry-> | |
2219 | consume_q); | |
2220 | else | |
2221 | qp_host_unregister_user_memory(entry->produce_q, | |
2222 | entry-> | |
2223 | consume_q); | |
2224 | ||
2225 | } | |
2226 | ||
2227 | if (!headers_mapped) | |
2228 | qp_reset_saved_headers(entry); | |
2229 | ||
2230 | qp_release_queue_mutex(entry->produce_q); | |
2231 | ||
2232 | if (!headers_mapped && entry->wakeup_cb) | |
2233 | entry->wakeup_cb(entry->client_data); | |
2234 | ||
2235 | } else { | |
2236 | if (entry->wakeup_cb) { | |
2237 | entry->wakeup_cb = NULL; | |
2238 | entry->client_data = NULL; | |
2239 | } | |
2240 | } | |
2241 | ||
2242 | if (entry->qp.ref_count == 0) { | |
2243 | qp_list_remove_entry(&qp_broker_list, &entry->qp); | |
2244 | ||
2245 | if (is_local) | |
2246 | kfree(entry->local_mem); | |
2247 | ||
2248 | qp_cleanup_queue_mutex(entry->produce_q, entry->consume_q); | |
2249 | qp_host_free_queue(entry->produce_q, entry->qp.produce_size); | |
2250 | qp_host_free_queue(entry->consume_q, entry->qp.consume_size); | |
2251 | /* Unlink from resource hash table and free callback */ | |
2252 | vmci_resource_remove(&entry->resource); | |
2253 | ||
2254 | kfree(entry); | |
2255 | ||
2256 | vmci_ctx_qp_destroy(context, handle); | |
2257 | } else { | |
2258 | qp_notify_peer(false, handle, context_id, peer_id); | |
2259 | if (context_id == VMCI_HOST_CONTEXT_ID && | |
2260 | QPBROKERSTATE_HAS_MEM(entry)) { | |
2261 | entry->state = VMCIQPB_SHUTDOWN_MEM; | |
2262 | } else { | |
2263 | entry->state = VMCIQPB_SHUTDOWN_NO_MEM; | |
2264 | } | |
2265 | ||
2266 | if (!is_local) | |
2267 | vmci_ctx_qp_destroy(context, handle); | |
2268 | ||
2269 | } | |
2270 | result = VMCI_SUCCESS; | |
2271 | out: | |
2272 | mutex_unlock(&qp_broker_list.mutex); | |
2273 | return result; | |
2274 | } | |
2275 | ||
2276 | /* | |
2277 | * Establishes the necessary mappings for a queue pair given a | |
2278 | * reference to the queue pair guest memory. This is usually | |
2279 | * called when a guest is unquiesced and the VMX is allowed to | |
2280 | * map guest memory once again. | |
2281 | */ | |
2282 | int vmci_qp_broker_map(struct vmci_handle handle, | |
2283 | struct vmci_ctx *context, | |
2284 | u64 guest_mem) | |
2285 | { | |
2286 | struct qp_broker_entry *entry; | |
2287 | const u32 context_id = vmci_ctx_get_id(context); | |
2288 | bool is_local = false; | |
2289 | int result; | |
2290 | ||
2291 | if (vmci_handle_is_invalid(handle) || !context || | |
2292 | context_id == VMCI_INVALID_ID) | |
2293 | return VMCI_ERROR_INVALID_ARGS; | |
2294 | ||
2295 | mutex_lock(&qp_broker_list.mutex); | |
2296 | ||
2297 | if (!vmci_ctx_qp_exists(context, handle)) { | |
2298 | pr_devel("Context (ID=0x%x) not attached to queue pair (handle=0x%x:0x%x)\n", | |
2299 | context_id, handle.context, handle.resource); | |
2300 | result = VMCI_ERROR_NOT_FOUND; | |
2301 | goto out; | |
2302 | } | |
2303 | ||
2304 | entry = qp_broker_handle_to_entry(handle); | |
2305 | if (!entry) { | |
2306 | pr_devel("Context (ID=0x%x) reports being attached to queue pair (handle=0x%x:0x%x) that isn't present in broker\n", | |
2307 | context_id, handle.context, handle.resource); | |
2308 | result = VMCI_ERROR_NOT_FOUND; | |
2309 | goto out; | |
2310 | } | |
2311 | ||
2312 | if (context_id != entry->create_id && context_id != entry->attach_id) { | |
2313 | result = VMCI_ERROR_QUEUEPAIR_NOTATTACHED; | |
2314 | goto out; | |
2315 | } | |
2316 | ||
2317 | is_local = entry->qp.flags & VMCI_QPFLAG_LOCAL; | |
2318 | result = VMCI_SUCCESS; | |
2319 | ||
2320 | if (context_id != VMCI_HOST_CONTEXT_ID) { | |
2321 | struct vmci_qp_page_store page_store; | |
2322 | ||
2323 | page_store.pages = guest_mem; | |
2324 | page_store.len = QPE_NUM_PAGES(entry->qp); | |
2325 | ||
2326 | qp_acquire_queue_mutex(entry->produce_q); | |
2327 | qp_reset_saved_headers(entry); | |
2328 | result = | |
2329 | qp_host_register_user_memory(&page_store, | |
2330 | entry->produce_q, | |
2331 | entry->consume_q); | |
2332 | qp_release_queue_mutex(entry->produce_q); | |
2333 | if (result == VMCI_SUCCESS) { | |
2334 | /* Move state from *_NO_MEM to *_MEM */ | |
2335 | ||
2336 | entry->state++; | |
2337 | ||
2338 | if (entry->wakeup_cb) | |
2339 | entry->wakeup_cb(entry->client_data); | |
2340 | } | |
2341 | } | |
2342 | ||
2343 | out: | |
2344 | mutex_unlock(&qp_broker_list.mutex); | |
2345 | return result; | |
2346 | } | |
2347 | ||
2348 | /* | |
2349 | * Saves a snapshot of the queue headers for the given QP broker | |
2350 | * entry. Should be used when guest memory is unmapped. | |
2351 | * Results: | |
2352 | * VMCI_SUCCESS on success, appropriate error code if guest memory | |
2353 | * can't be accessed.. | |
2354 | */ | |
2355 | static int qp_save_headers(struct qp_broker_entry *entry) | |
2356 | { | |
2357 | int result; | |
2358 | ||
2359 | if (entry->produce_q->saved_header != NULL && | |
2360 | entry->consume_q->saved_header != NULL) { | |
2361 | /* | |
2362 | * If the headers have already been saved, we don't need to do | |
2363 | * it again, and we don't want to map in the headers | |
2364 | * unnecessarily. | |
2365 | */ | |
2366 | ||
2367 | return VMCI_SUCCESS; | |
2368 | } | |
2369 | ||
2370 | if (NULL == entry->produce_q->q_header || | |
2371 | NULL == entry->consume_q->q_header) { | |
2372 | result = qp_host_map_queues(entry->produce_q, entry->consume_q); | |
2373 | if (result < VMCI_SUCCESS) | |
2374 | return result; | |
2375 | } | |
2376 | ||
2377 | memcpy(&entry->saved_produce_q, entry->produce_q->q_header, | |
2378 | sizeof(entry->saved_produce_q)); | |
2379 | entry->produce_q->saved_header = &entry->saved_produce_q; | |
2380 | memcpy(&entry->saved_consume_q, entry->consume_q->q_header, | |
2381 | sizeof(entry->saved_consume_q)); | |
2382 | entry->consume_q->saved_header = &entry->saved_consume_q; | |
2383 | ||
2384 | return VMCI_SUCCESS; | |
2385 | } | |
2386 | ||
2387 | /* | |
2388 | * Removes all references to the guest memory of a given queue pair, and | |
2389 | * will move the queue pair from state *_MEM to *_NO_MEM. It is usually | |
2390 | * called when a VM is being quiesced where access to guest memory should | |
2391 | * avoided. | |
2392 | */ | |
2393 | int vmci_qp_broker_unmap(struct vmci_handle handle, | |
2394 | struct vmci_ctx *context, | |
2395 | u32 gid) | |
2396 | { | |
2397 | struct qp_broker_entry *entry; | |
2398 | const u32 context_id = vmci_ctx_get_id(context); | |
2399 | bool is_local = false; | |
2400 | int result; | |
2401 | ||
2402 | if (vmci_handle_is_invalid(handle) || !context || | |
2403 | context_id == VMCI_INVALID_ID) | |
2404 | return VMCI_ERROR_INVALID_ARGS; | |
2405 | ||
2406 | mutex_lock(&qp_broker_list.mutex); | |
2407 | ||
2408 | if (!vmci_ctx_qp_exists(context, handle)) { | |
2409 | pr_devel("Context (ID=0x%x) not attached to queue pair (handle=0x%x:0x%x)\n", | |
2410 | context_id, handle.context, handle.resource); | |
2411 | result = VMCI_ERROR_NOT_FOUND; | |
2412 | goto out; | |
2413 | } | |
2414 | ||
2415 | entry = qp_broker_handle_to_entry(handle); | |
2416 | if (!entry) { | |
2417 | pr_devel("Context (ID=0x%x) reports being attached to queue pair (handle=0x%x:0x%x) that isn't present in broker\n", | |
2418 | context_id, handle.context, handle.resource); | |
2419 | result = VMCI_ERROR_NOT_FOUND; | |
2420 | goto out; | |
2421 | } | |
2422 | ||
2423 | if (context_id != entry->create_id && context_id != entry->attach_id) { | |
2424 | result = VMCI_ERROR_QUEUEPAIR_NOTATTACHED; | |
2425 | goto out; | |
2426 | } | |
2427 | ||
2428 | is_local = entry->qp.flags & VMCI_QPFLAG_LOCAL; | |
2429 | ||
2430 | if (context_id != VMCI_HOST_CONTEXT_ID) { | |
2431 | qp_acquire_queue_mutex(entry->produce_q); | |
2432 | result = qp_save_headers(entry); | |
2433 | if (result < VMCI_SUCCESS) | |
2434 | pr_warn("Failed to save queue headers for queue pair (handle=0x%x:0x%x,result=%d)\n", | |
2435 | handle.context, handle.resource, result); | |
2436 | ||
2437 | qp_host_unmap_queues(gid, entry->produce_q, entry->consume_q); | |
2438 | ||
2439 | /* | |
2440 | * On hosted, when we unmap queue pairs, the VMX will also | |
2441 | * unmap the guest memory, so we invalidate the previously | |
2442 | * registered memory. If the queue pair is mapped again at a | |
2443 | * later point in time, we will need to reregister the user | |
2444 | * memory with a possibly new user VA. | |
2445 | */ | |
2446 | qp_host_unregister_user_memory(entry->produce_q, | |
2447 | entry->consume_q); | |
2448 | ||
2449 | /* | |
2450 | * Move state from *_MEM to *_NO_MEM. | |
2451 | */ | |
2452 | entry->state--; | |
2453 | ||
2454 | qp_release_queue_mutex(entry->produce_q); | |
2455 | } | |
2456 | ||
2457 | result = VMCI_SUCCESS; | |
2458 | ||
2459 | out: | |
2460 | mutex_unlock(&qp_broker_list.mutex); | |
2461 | return result; | |
2462 | } | |
2463 | ||
2464 | /* | |
2465 | * Destroys all guest queue pair endpoints. If active guest queue | |
2466 | * pairs still exist, hypercalls to attempt detach from these | |
2467 | * queue pairs will be made. Any failure to detach is silently | |
2468 | * ignored. | |
2469 | */ | |
2470 | void vmci_qp_guest_endpoints_exit(void) | |
2471 | { | |
2472 | struct qp_entry *entry; | |
2473 | struct qp_guest_endpoint *ep; | |
2474 | ||
2475 | mutex_lock(&qp_guest_endpoints.mutex); | |
2476 | ||
2477 | while ((entry = qp_list_get_head(&qp_guest_endpoints))) { | |
2478 | ep = (struct qp_guest_endpoint *)entry; | |
2479 | ||
2480 | /* Don't make a hypercall for local queue_pairs. */ | |
2481 | if (!(entry->flags & VMCI_QPFLAG_LOCAL)) | |
2482 | qp_detatch_hypercall(entry->handle); | |
2483 | ||
2484 | /* We cannot fail the exit, so let's reset ref_count. */ | |
2485 | entry->ref_count = 0; | |
2486 | qp_list_remove_entry(&qp_guest_endpoints, entry); | |
2487 | ||
2488 | qp_guest_endpoint_destroy(ep); | |
2489 | } | |
2490 | ||
2491 | mutex_unlock(&qp_guest_endpoints.mutex); | |
2492 | } | |
2493 | ||
2494 | /* | |
2495 | * Helper routine that will lock the queue pair before subsequent | |
2496 | * operations. | |
2497 | * Note: Non-blocking on the host side is currently only implemented in ESX. | |
2498 | * Since non-blocking isn't yet implemented on the host personality we | |
2499 | * have no reason to acquire a spin lock. So to avoid the use of an | |
2500 | * unnecessary lock only acquire the mutex if we can block. | |
06164d2b GZ |
2501 | */ |
2502 | static void qp_lock(const struct vmci_qp *qpair) | |
2503 | { | |
45412bef | 2504 | qp_acquire_queue_mutex(qpair->produce_q); |
06164d2b GZ |
2505 | } |
2506 | ||
2507 | /* | |
2508 | * Helper routine that unlocks the queue pair after calling | |
45412bef | 2509 | * qp_lock. |
06164d2b GZ |
2510 | */ |
2511 | static void qp_unlock(const struct vmci_qp *qpair) | |
2512 | { | |
45412bef | 2513 | qp_release_queue_mutex(qpair->produce_q); |
06164d2b GZ |
2514 | } |
2515 | ||
2516 | /* | |
2517 | * The queue headers may not be mapped at all times. If a queue is | |
2518 | * currently not mapped, it will be attempted to do so. | |
2519 | */ | |
2520 | static int qp_map_queue_headers(struct vmci_queue *produce_q, | |
45412bef | 2521 | struct vmci_queue *consume_q) |
06164d2b GZ |
2522 | { |
2523 | int result; | |
2524 | ||
2525 | if (NULL == produce_q->q_header || NULL == consume_q->q_header) { | |
45412bef | 2526 | result = qp_host_map_queues(produce_q, consume_q); |
06164d2b GZ |
2527 | if (result < VMCI_SUCCESS) |
2528 | return (produce_q->saved_header && | |
2529 | consume_q->saved_header) ? | |
2530 | VMCI_ERROR_QUEUEPAIR_NOT_READY : | |
2531 | VMCI_ERROR_QUEUEPAIR_NOTATTACHED; | |
2532 | } | |
2533 | ||
2534 | return VMCI_SUCCESS; | |
2535 | } | |
2536 | ||
2537 | /* | |
2538 | * Helper routine that will retrieve the produce and consume | |
2539 | * headers of a given queue pair. If the guest memory of the | |
2540 | * queue pair is currently not available, the saved queue headers | |
2541 | * will be returned, if these are available. | |
2542 | */ | |
2543 | static int qp_get_queue_headers(const struct vmci_qp *qpair, | |
2544 | struct vmci_queue_header **produce_q_header, | |
2545 | struct vmci_queue_header **consume_q_header) | |
2546 | { | |
2547 | int result; | |
2548 | ||
45412bef | 2549 | result = qp_map_queue_headers(qpair->produce_q, qpair->consume_q); |
06164d2b GZ |
2550 | if (result == VMCI_SUCCESS) { |
2551 | *produce_q_header = qpair->produce_q->q_header; | |
2552 | *consume_q_header = qpair->consume_q->q_header; | |
2553 | } else if (qpair->produce_q->saved_header && | |
2554 | qpair->consume_q->saved_header) { | |
2555 | *produce_q_header = qpair->produce_q->saved_header; | |
2556 | *consume_q_header = qpair->consume_q->saved_header; | |
2557 | result = VMCI_SUCCESS; | |
2558 | } | |
2559 | ||
2560 | return result; | |
2561 | } | |
2562 | ||
2563 | /* | |
2564 | * Callback from VMCI queue pair broker indicating that a queue | |
2565 | * pair that was previously not ready, now either is ready or | |
2566 | * gone forever. | |
2567 | */ | |
2568 | static int qp_wakeup_cb(void *client_data) | |
2569 | { | |
2570 | struct vmci_qp *qpair = (struct vmci_qp *)client_data; | |
2571 | ||
2572 | qp_lock(qpair); | |
2573 | while (qpair->blocked > 0) { | |
2574 | qpair->blocked--; | |
2575 | qpair->generation++; | |
2576 | wake_up(&qpair->event); | |
2577 | } | |
2578 | qp_unlock(qpair); | |
2579 | ||
2580 | return VMCI_SUCCESS; | |
2581 | } | |
2582 | ||
2583 | /* | |
2584 | * Makes the calling thread wait for the queue pair to become | |
2585 | * ready for host side access. Returns true when thread is | |
2586 | * woken up after queue pair state change, false otherwise. | |
2587 | */ | |
2588 | static bool qp_wait_for_ready_queue(struct vmci_qp *qpair) | |
2589 | { | |
2590 | unsigned int generation; | |
2591 | ||
06164d2b GZ |
2592 | qpair->blocked++; |
2593 | generation = qpair->generation; | |
2594 | qp_unlock(qpair); | |
2595 | wait_event(qpair->event, generation != qpair->generation); | |
2596 | qp_lock(qpair); | |
2597 | ||
2598 | return true; | |
2599 | } | |
2600 | ||
2601 | /* | |
2602 | * Enqueues a given buffer to the produce queue using the provided | |
2603 | * function. As many bytes as possible (space available in the queue) | |
2604 | * are enqueued. Assumes the queue->mutex has been acquired. Returns | |
2605 | * VMCI_ERROR_QUEUEPAIR_NOSPACE if no space was available to enqueue | |
2606 | * data, VMCI_ERROR_INVALID_SIZE, if any queue pointer is outside the | |
2607 | * queue (as defined by the queue size), VMCI_ERROR_INVALID_ARGS, if | |
2608 | * an error occured when accessing the buffer, | |
2609 | * VMCI_ERROR_QUEUEPAIR_NOTATTACHED, if the queue pair pages aren't | |
2610 | * available. Otherwise, the number of bytes written to the queue is | |
2611 | * returned. Updates the tail pointer of the produce queue. | |
2612 | */ | |
2613 | static ssize_t qp_enqueue_locked(struct vmci_queue *produce_q, | |
2614 | struct vmci_queue *consume_q, | |
2615 | const u64 produce_q_size, | |
2616 | const void *buf, | |
2617 | size_t buf_size, | |
45412bef | 2618 | vmci_memcpy_to_queue_func memcpy_to_queue) |
06164d2b GZ |
2619 | { |
2620 | s64 free_space; | |
2621 | u64 tail; | |
2622 | size_t written; | |
2623 | ssize_t result; | |
2624 | ||
45412bef | 2625 | result = qp_map_queue_headers(produce_q, consume_q); |
06164d2b GZ |
2626 | if (unlikely(result != VMCI_SUCCESS)) |
2627 | return result; | |
2628 | ||
2629 | free_space = vmci_q_header_free_space(produce_q->q_header, | |
2630 | consume_q->q_header, | |
2631 | produce_q_size); | |
2632 | if (free_space == 0) | |
2633 | return VMCI_ERROR_QUEUEPAIR_NOSPACE; | |
2634 | ||
2635 | if (free_space < VMCI_SUCCESS) | |
2636 | return (ssize_t) free_space; | |
2637 | ||
2638 | written = (size_t) (free_space > buf_size ? buf_size : free_space); | |
2639 | tail = vmci_q_header_producer_tail(produce_q->q_header); | |
2640 | if (likely(tail + written < produce_q_size)) { | |
2641 | result = memcpy_to_queue(produce_q, tail, buf, 0, written); | |
2642 | } else { | |
2643 | /* Tail pointer wraps around. */ | |
2644 | ||
2645 | const size_t tmp = (size_t) (produce_q_size - tail); | |
2646 | ||
2647 | result = memcpy_to_queue(produce_q, tail, buf, 0, tmp); | |
2648 | if (result >= VMCI_SUCCESS) | |
2649 | result = memcpy_to_queue(produce_q, 0, buf, tmp, | |
2650 | written - tmp); | |
2651 | } | |
2652 | ||
2653 | if (result < VMCI_SUCCESS) | |
2654 | return result; | |
2655 | ||
2656 | vmci_q_header_add_producer_tail(produce_q->q_header, written, | |
2657 | produce_q_size); | |
2658 | return written; | |
2659 | } | |
2660 | ||
2661 | /* | |
2662 | * Dequeues data (if available) from the given consume queue. Writes data | |
2663 | * to the user provided buffer using the provided function. | |
2664 | * Assumes the queue->mutex has been acquired. | |
2665 | * Results: | |
2666 | * VMCI_ERROR_QUEUEPAIR_NODATA if no data was available to dequeue. | |
2667 | * VMCI_ERROR_INVALID_SIZE, if any queue pointer is outside the queue | |
2668 | * (as defined by the queue size). | |
2669 | * VMCI_ERROR_INVALID_ARGS, if an error occured when accessing the buffer. | |
2670 | * Otherwise the number of bytes dequeued is returned. | |
2671 | * Side effects: | |
2672 | * Updates the head pointer of the consume queue. | |
2673 | */ | |
2674 | static ssize_t qp_dequeue_locked(struct vmci_queue *produce_q, | |
2675 | struct vmci_queue *consume_q, | |
2676 | const u64 consume_q_size, | |
2677 | void *buf, | |
2678 | size_t buf_size, | |
2679 | vmci_memcpy_from_queue_func memcpy_from_queue, | |
45412bef | 2680 | bool update_consumer) |
06164d2b GZ |
2681 | { |
2682 | s64 buf_ready; | |
2683 | u64 head; | |
2684 | size_t read; | |
2685 | ssize_t result; | |
2686 | ||
45412bef | 2687 | result = qp_map_queue_headers(produce_q, consume_q); |
06164d2b GZ |
2688 | if (unlikely(result != VMCI_SUCCESS)) |
2689 | return result; | |
2690 | ||
2691 | buf_ready = vmci_q_header_buf_ready(consume_q->q_header, | |
2692 | produce_q->q_header, | |
2693 | consume_q_size); | |
2694 | if (buf_ready == 0) | |
2695 | return VMCI_ERROR_QUEUEPAIR_NODATA; | |
2696 | ||
2697 | if (buf_ready < VMCI_SUCCESS) | |
2698 | return (ssize_t) buf_ready; | |
2699 | ||
2700 | read = (size_t) (buf_ready > buf_size ? buf_size : buf_ready); | |
2701 | head = vmci_q_header_consumer_head(produce_q->q_header); | |
2702 | if (likely(head + read < consume_q_size)) { | |
2703 | result = memcpy_from_queue(buf, 0, consume_q, head, read); | |
2704 | } else { | |
2705 | /* Head pointer wraps around. */ | |
2706 | ||
2707 | const size_t tmp = (size_t) (consume_q_size - head); | |
2708 | ||
2709 | result = memcpy_from_queue(buf, 0, consume_q, head, tmp); | |
2710 | if (result >= VMCI_SUCCESS) | |
2711 | result = memcpy_from_queue(buf, tmp, consume_q, 0, | |
2712 | read - tmp); | |
2713 | ||
2714 | } | |
2715 | ||
2716 | if (result < VMCI_SUCCESS) | |
2717 | return result; | |
2718 | ||
2719 | if (update_consumer) | |
2720 | vmci_q_header_add_consumer_head(produce_q->q_header, | |
2721 | read, consume_q_size); | |
2722 | ||
2723 | return read; | |
2724 | } | |
2725 | ||
2726 | /* | |
2727 | * vmci_qpair_alloc() - Allocates a queue pair. | |
2728 | * @qpair: Pointer for the new vmci_qp struct. | |
2729 | * @handle: Handle to track the resource. | |
2730 | * @produce_qsize: Desired size of the producer queue. | |
2731 | * @consume_qsize: Desired size of the consumer queue. | |
2732 | * @peer: ContextID of the peer. | |
2733 | * @flags: VMCI flags. | |
2734 | * @priv_flags: VMCI priviledge flags. | |
2735 | * | |
2736 | * This is the client interface for allocating the memory for a | |
2737 | * vmci_qp structure and then attaching to the underlying | |
2738 | * queue. If an error occurs allocating the memory for the | |
2739 | * vmci_qp structure no attempt is made to attach. If an | |
2740 | * error occurs attaching, then the structure is freed. | |
2741 | */ | |
2742 | int vmci_qpair_alloc(struct vmci_qp **qpair, | |
2743 | struct vmci_handle *handle, | |
2744 | u64 produce_qsize, | |
2745 | u64 consume_qsize, | |
2746 | u32 peer, | |
2747 | u32 flags, | |
2748 | u32 priv_flags) | |
2749 | { | |
2750 | struct vmci_qp *my_qpair; | |
2751 | int retval; | |
2752 | struct vmci_handle src = VMCI_INVALID_HANDLE; | |
2753 | struct vmci_handle dst = vmci_make_handle(peer, VMCI_INVALID_ID); | |
2754 | enum vmci_route route; | |
2755 | vmci_event_release_cb wakeup_cb; | |
2756 | void *client_data; | |
2757 | ||
2758 | /* | |
2759 | * Restrict the size of a queuepair. The device already | |
2760 | * enforces a limit on the total amount of memory that can be | |
2761 | * allocated to queuepairs for a guest. However, we try to | |
2762 | * allocate this memory before we make the queuepair | |
2763 | * allocation hypercall. On Linux, we allocate each page | |
2764 | * separately, which means rather than fail, the guest will | |
2765 | * thrash while it tries to allocate, and will become | |
2766 | * increasingly unresponsive to the point where it appears to | |
2767 | * be hung. So we place a limit on the size of an individual | |
2768 | * queuepair here, and leave the device to enforce the | |
2769 | * restriction on total queuepair memory. (Note that this | |
2770 | * doesn't prevent all cases; a user with only this much | |
2771 | * physical memory could still get into trouble.) The error | |
2772 | * used by the device is NO_RESOURCES, so use that here too. | |
2773 | */ | |
2774 | ||
2775 | if (produce_qsize + consume_qsize < max(produce_qsize, consume_qsize) || | |
2776 | produce_qsize + consume_qsize > VMCI_MAX_GUEST_QP_MEMORY) | |
2777 | return VMCI_ERROR_NO_RESOURCES; | |
2778 | ||
2779 | retval = vmci_route(&src, &dst, false, &route); | |
2780 | if (retval < VMCI_SUCCESS) | |
2781 | route = vmci_guest_code_active() ? | |
2782 | VMCI_ROUTE_AS_GUEST : VMCI_ROUTE_AS_HOST; | |
2783 | ||
45412bef AK |
2784 | if (flags & (VMCI_QPFLAG_NONBLOCK | VMCI_QPFLAG_PINNED)) { |
2785 | pr_devel("NONBLOCK OR PINNED set"); | |
06164d2b GZ |
2786 | return VMCI_ERROR_INVALID_ARGS; |
2787 | } | |
2788 | ||
06164d2b GZ |
2789 | my_qpair = kzalloc(sizeof(*my_qpair), GFP_KERNEL); |
2790 | if (!my_qpair) | |
2791 | return VMCI_ERROR_NO_MEM; | |
2792 | ||
2793 | my_qpair->produce_q_size = produce_qsize; | |
2794 | my_qpair->consume_q_size = consume_qsize; | |
2795 | my_qpair->peer = peer; | |
2796 | my_qpair->flags = flags; | |
2797 | my_qpair->priv_flags = priv_flags; | |
2798 | ||
2799 | wakeup_cb = NULL; | |
2800 | client_data = NULL; | |
2801 | ||
2802 | if (VMCI_ROUTE_AS_HOST == route) { | |
2803 | my_qpair->guest_endpoint = false; | |
2804 | if (!(flags & VMCI_QPFLAG_LOCAL)) { | |
2805 | my_qpair->blocked = 0; | |
2806 | my_qpair->generation = 0; | |
2807 | init_waitqueue_head(&my_qpair->event); | |
2808 | wakeup_cb = qp_wakeup_cb; | |
2809 | client_data = (void *)my_qpair; | |
2810 | } | |
2811 | } else { | |
2812 | my_qpair->guest_endpoint = true; | |
2813 | } | |
2814 | ||
2815 | retval = vmci_qp_alloc(handle, | |
2816 | &my_qpair->produce_q, | |
2817 | my_qpair->produce_q_size, | |
2818 | &my_qpair->consume_q, | |
2819 | my_qpair->consume_q_size, | |
2820 | my_qpair->peer, | |
2821 | my_qpair->flags, | |
2822 | my_qpair->priv_flags, | |
2823 | my_qpair->guest_endpoint, | |
2824 | wakeup_cb, client_data); | |
2825 | ||
2826 | if (retval < VMCI_SUCCESS) { | |
2827 | kfree(my_qpair); | |
2828 | return retval; | |
2829 | } | |
2830 | ||
2831 | *qpair = my_qpair; | |
2832 | my_qpair->handle = *handle; | |
2833 | ||
2834 | return retval; | |
2835 | } | |
2836 | EXPORT_SYMBOL_GPL(vmci_qpair_alloc); | |
2837 | ||
2838 | /* | |
2839 | * vmci_qpair_detach() - Detatches the client from a queue pair. | |
2840 | * @qpair: Reference of a pointer to the qpair struct. | |
2841 | * | |
2842 | * This is the client interface for detaching from a VMCIQPair. | |
2843 | * Note that this routine will free the memory allocated for the | |
2844 | * vmci_qp structure too. | |
2845 | */ | |
2846 | int vmci_qpair_detach(struct vmci_qp **qpair) | |
2847 | { | |
2848 | int result; | |
2849 | struct vmci_qp *old_qpair; | |
2850 | ||
2851 | if (!qpair || !(*qpair)) | |
2852 | return VMCI_ERROR_INVALID_ARGS; | |
2853 | ||
2854 | old_qpair = *qpair; | |
2855 | result = qp_detatch(old_qpair->handle, old_qpair->guest_endpoint); | |
2856 | ||
2857 | /* | |
2858 | * The guest can fail to detach for a number of reasons, and | |
2859 | * if it does so, it will cleanup the entry (if there is one). | |
2860 | * The host can fail too, but it won't cleanup the entry | |
2861 | * immediately, it will do that later when the context is | |
2862 | * freed. Either way, we need to release the qpair struct | |
2863 | * here; there isn't much the caller can do, and we don't want | |
2864 | * to leak. | |
2865 | */ | |
2866 | ||
2867 | memset(old_qpair, 0, sizeof(*old_qpair)); | |
2868 | old_qpair->handle = VMCI_INVALID_HANDLE; | |
2869 | old_qpair->peer = VMCI_INVALID_ID; | |
2870 | kfree(old_qpair); | |
2871 | *qpair = NULL; | |
2872 | ||
2873 | return result; | |
2874 | } | |
2875 | EXPORT_SYMBOL_GPL(vmci_qpair_detach); | |
2876 | ||
2877 | /* | |
2878 | * vmci_qpair_get_produce_indexes() - Retrieves the indexes of the producer. | |
2879 | * @qpair: Pointer to the queue pair struct. | |
2880 | * @producer_tail: Reference used for storing producer tail index. | |
2881 | * @consumer_head: Reference used for storing the consumer head index. | |
2882 | * | |
2883 | * This is the client interface for getting the current indexes of the | |
2884 | * QPair from the point of the view of the caller as the producer. | |
2885 | */ | |
2886 | int vmci_qpair_get_produce_indexes(const struct vmci_qp *qpair, | |
2887 | u64 *producer_tail, | |
2888 | u64 *consumer_head) | |
2889 | { | |
2890 | struct vmci_queue_header *produce_q_header; | |
2891 | struct vmci_queue_header *consume_q_header; | |
2892 | int result; | |
2893 | ||
2894 | if (!qpair) | |
2895 | return VMCI_ERROR_INVALID_ARGS; | |
2896 | ||
2897 | qp_lock(qpair); | |
2898 | result = | |
2899 | qp_get_queue_headers(qpair, &produce_q_header, &consume_q_header); | |
2900 | if (result == VMCI_SUCCESS) | |
2901 | vmci_q_header_get_pointers(produce_q_header, consume_q_header, | |
2902 | producer_tail, consumer_head); | |
2903 | qp_unlock(qpair); | |
2904 | ||
2905 | if (result == VMCI_SUCCESS && | |
2906 | ((producer_tail && *producer_tail >= qpair->produce_q_size) || | |
2907 | (consumer_head && *consumer_head >= qpair->produce_q_size))) | |
2908 | return VMCI_ERROR_INVALID_SIZE; | |
2909 | ||
2910 | return result; | |
2911 | } | |
2912 | EXPORT_SYMBOL_GPL(vmci_qpair_get_produce_indexes); | |
2913 | ||
2914 | /* | |
2915 | * vmci_qpair_get_consume_indexes() - Retrieves the indexes of the comsumer. | |
2916 | * @qpair: Pointer to the queue pair struct. | |
2917 | * @consumer_tail: Reference used for storing consumer tail index. | |
2918 | * @producer_head: Reference used for storing the producer head index. | |
2919 | * | |
2920 | * This is the client interface for getting the current indexes of the | |
2921 | * QPair from the point of the view of the caller as the consumer. | |
2922 | */ | |
2923 | int vmci_qpair_get_consume_indexes(const struct vmci_qp *qpair, | |
2924 | u64 *consumer_tail, | |
2925 | u64 *producer_head) | |
2926 | { | |
2927 | struct vmci_queue_header *produce_q_header; | |
2928 | struct vmci_queue_header *consume_q_header; | |
2929 | int result; | |
2930 | ||
2931 | if (!qpair) | |
2932 | return VMCI_ERROR_INVALID_ARGS; | |
2933 | ||
2934 | qp_lock(qpair); | |
2935 | result = | |
2936 | qp_get_queue_headers(qpair, &produce_q_header, &consume_q_header); | |
2937 | if (result == VMCI_SUCCESS) | |
2938 | vmci_q_header_get_pointers(consume_q_header, produce_q_header, | |
2939 | consumer_tail, producer_head); | |
2940 | qp_unlock(qpair); | |
2941 | ||
2942 | if (result == VMCI_SUCCESS && | |
2943 | ((consumer_tail && *consumer_tail >= qpair->consume_q_size) || | |
2944 | (producer_head && *producer_head >= qpair->consume_q_size))) | |
2945 | return VMCI_ERROR_INVALID_SIZE; | |
2946 | ||
2947 | return result; | |
2948 | } | |
2949 | EXPORT_SYMBOL_GPL(vmci_qpair_get_consume_indexes); | |
2950 | ||
2951 | /* | |
2952 | * vmci_qpair_produce_free_space() - Retrieves free space in producer queue. | |
2953 | * @qpair: Pointer to the queue pair struct. | |
2954 | * | |
2955 | * This is the client interface for getting the amount of free | |
2956 | * space in the QPair from the point of the view of the caller as | |
2957 | * the producer which is the common case. Returns < 0 if err, else | |
2958 | * available bytes into which data can be enqueued if > 0. | |
2959 | */ | |
2960 | s64 vmci_qpair_produce_free_space(const struct vmci_qp *qpair) | |
2961 | { | |
2962 | struct vmci_queue_header *produce_q_header; | |
2963 | struct vmci_queue_header *consume_q_header; | |
2964 | s64 result; | |
2965 | ||
2966 | if (!qpair) | |
2967 | return VMCI_ERROR_INVALID_ARGS; | |
2968 | ||
2969 | qp_lock(qpair); | |
2970 | result = | |
2971 | qp_get_queue_headers(qpair, &produce_q_header, &consume_q_header); | |
2972 | if (result == VMCI_SUCCESS) | |
2973 | result = vmci_q_header_free_space(produce_q_header, | |
2974 | consume_q_header, | |
2975 | qpair->produce_q_size); | |
2976 | else | |
2977 | result = 0; | |
2978 | ||
2979 | qp_unlock(qpair); | |
2980 | ||
2981 | return result; | |
2982 | } | |
2983 | EXPORT_SYMBOL_GPL(vmci_qpair_produce_free_space); | |
2984 | ||
2985 | /* | |
2986 | * vmci_qpair_consume_free_space() - Retrieves free space in consumer queue. | |
2987 | * @qpair: Pointer to the queue pair struct. | |
2988 | * | |
2989 | * This is the client interface for getting the amount of free | |
2990 | * space in the QPair from the point of the view of the caller as | |
2991 | * the consumer which is not the common case. Returns < 0 if err, else | |
2992 | * available bytes into which data can be enqueued if > 0. | |
2993 | */ | |
2994 | s64 vmci_qpair_consume_free_space(const struct vmci_qp *qpair) | |
2995 | { | |
2996 | struct vmci_queue_header *produce_q_header; | |
2997 | struct vmci_queue_header *consume_q_header; | |
2998 | s64 result; | |
2999 | ||
3000 | if (!qpair) | |
3001 | return VMCI_ERROR_INVALID_ARGS; | |
3002 | ||
3003 | qp_lock(qpair); | |
3004 | result = | |
3005 | qp_get_queue_headers(qpair, &produce_q_header, &consume_q_header); | |
3006 | if (result == VMCI_SUCCESS) | |
3007 | result = vmci_q_header_free_space(consume_q_header, | |
3008 | produce_q_header, | |
3009 | qpair->consume_q_size); | |
3010 | else | |
3011 | result = 0; | |
3012 | ||
3013 | qp_unlock(qpair); | |
3014 | ||
3015 | return result; | |
3016 | } | |
3017 | EXPORT_SYMBOL_GPL(vmci_qpair_consume_free_space); | |
3018 | ||
3019 | /* | |
3020 | * vmci_qpair_produce_buf_ready() - Gets bytes ready to read from | |
3021 | * producer queue. | |
3022 | * @qpair: Pointer to the queue pair struct. | |
3023 | * | |
3024 | * This is the client interface for getting the amount of | |
3025 | * enqueued data in the QPair from the point of the view of the | |
3026 | * caller as the producer which is not the common case. Returns < 0 if err, | |
3027 | * else available bytes that may be read. | |
3028 | */ | |
3029 | s64 vmci_qpair_produce_buf_ready(const struct vmci_qp *qpair) | |
3030 | { | |
3031 | struct vmci_queue_header *produce_q_header; | |
3032 | struct vmci_queue_header *consume_q_header; | |
3033 | s64 result; | |
3034 | ||
3035 | if (!qpair) | |
3036 | return VMCI_ERROR_INVALID_ARGS; | |
3037 | ||
3038 | qp_lock(qpair); | |
3039 | result = | |
3040 | qp_get_queue_headers(qpair, &produce_q_header, &consume_q_header); | |
3041 | if (result == VMCI_SUCCESS) | |
3042 | result = vmci_q_header_buf_ready(produce_q_header, | |
3043 | consume_q_header, | |
3044 | qpair->produce_q_size); | |
3045 | else | |
3046 | result = 0; | |
3047 | ||
3048 | qp_unlock(qpair); | |
3049 | ||
3050 | return result; | |
3051 | } | |
3052 | EXPORT_SYMBOL_GPL(vmci_qpair_produce_buf_ready); | |
3053 | ||
3054 | /* | |
3055 | * vmci_qpair_consume_buf_ready() - Gets bytes ready to read from | |
3056 | * consumer queue. | |
3057 | * @qpair: Pointer to the queue pair struct. | |
3058 | * | |
3059 | * This is the client interface for getting the amount of | |
3060 | * enqueued data in the QPair from the point of the view of the | |
3061 | * caller as the consumer which is the normal case. Returns < 0 if err, | |
3062 | * else available bytes that may be read. | |
3063 | */ | |
3064 | s64 vmci_qpair_consume_buf_ready(const struct vmci_qp *qpair) | |
3065 | { | |
3066 | struct vmci_queue_header *produce_q_header; | |
3067 | struct vmci_queue_header *consume_q_header; | |
3068 | s64 result; | |
3069 | ||
3070 | if (!qpair) | |
3071 | return VMCI_ERROR_INVALID_ARGS; | |
3072 | ||
3073 | qp_lock(qpair); | |
3074 | result = | |
3075 | qp_get_queue_headers(qpair, &produce_q_header, &consume_q_header); | |
3076 | if (result == VMCI_SUCCESS) | |
3077 | result = vmci_q_header_buf_ready(consume_q_header, | |
3078 | produce_q_header, | |
3079 | qpair->consume_q_size); | |
3080 | else | |
3081 | result = 0; | |
3082 | ||
3083 | qp_unlock(qpair); | |
3084 | ||
3085 | return result; | |
3086 | } | |
3087 | EXPORT_SYMBOL_GPL(vmci_qpair_consume_buf_ready); | |
3088 | ||
3089 | /* | |
3090 | * vmci_qpair_enqueue() - Throw data on the queue. | |
3091 | * @qpair: Pointer to the queue pair struct. | |
3092 | * @buf: Pointer to buffer containing data | |
3093 | * @buf_size: Length of buffer. | |
3094 | * @buf_type: Buffer type (Unused). | |
3095 | * | |
3096 | * This is the client interface for enqueueing data into the queue. | |
3097 | * Returns number of bytes enqueued or < 0 on error. | |
3098 | */ | |
3099 | ssize_t vmci_qpair_enqueue(struct vmci_qp *qpair, | |
3100 | const void *buf, | |
3101 | size_t buf_size, | |
3102 | int buf_type) | |
3103 | { | |
3104 | ssize_t result; | |
3105 | ||
3106 | if (!qpair || !buf) | |
3107 | return VMCI_ERROR_INVALID_ARGS; | |
3108 | ||
3109 | qp_lock(qpair); | |
3110 | ||
3111 | do { | |
3112 | result = qp_enqueue_locked(qpair->produce_q, | |
3113 | qpair->consume_q, | |
3114 | qpair->produce_q_size, | |
3115 | buf, buf_size, | |
45412bef | 3116 | qp_memcpy_to_queue); |
06164d2b GZ |
3117 | |
3118 | if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY && | |
3119 | !qp_wait_for_ready_queue(qpair)) | |
3120 | result = VMCI_ERROR_WOULD_BLOCK; | |
3121 | ||
3122 | } while (result == VMCI_ERROR_QUEUEPAIR_NOT_READY); | |
3123 | ||
3124 | qp_unlock(qpair); | |
3125 | ||
3126 | return result; | |
3127 | } | |
3128 | EXPORT_SYMBOL_GPL(vmci_qpair_enqueue); | |
3129 | ||
3130 | /* | |
3131 | * vmci_qpair_dequeue() - Get data from the queue. | |
3132 | * @qpair: Pointer to the queue pair struct. | |
3133 | * @buf: Pointer to buffer for the data | |
3134 | * @buf_size: Length of buffer. | |
3135 | * @buf_type: Buffer type (Unused). | |
3136 | * | |
3137 | * This is the client interface for dequeueing data from the queue. | |
3138 | * Returns number of bytes dequeued or < 0 on error. | |
3139 | */ | |
3140 | ssize_t vmci_qpair_dequeue(struct vmci_qp *qpair, | |
3141 | void *buf, | |
3142 | size_t buf_size, | |
3143 | int buf_type) | |
3144 | { | |
3145 | ssize_t result; | |
3146 | ||
3147 | if (!qpair || !buf) | |
3148 | return VMCI_ERROR_INVALID_ARGS; | |
3149 | ||
3150 | qp_lock(qpair); | |
3151 | ||
3152 | do { | |
3153 | result = qp_dequeue_locked(qpair->produce_q, | |
3154 | qpair->consume_q, | |
3155 | qpair->consume_q_size, | |
3156 | buf, buf_size, | |
45412bef | 3157 | qp_memcpy_from_queue, true); |
06164d2b GZ |
3158 | |
3159 | if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY && | |
3160 | !qp_wait_for_ready_queue(qpair)) | |
3161 | result = VMCI_ERROR_WOULD_BLOCK; | |
3162 | ||
3163 | } while (result == VMCI_ERROR_QUEUEPAIR_NOT_READY); | |
3164 | ||
3165 | qp_unlock(qpair); | |
3166 | ||
3167 | return result; | |
3168 | } | |
3169 | EXPORT_SYMBOL_GPL(vmci_qpair_dequeue); | |
3170 | ||
3171 | /* | |
3172 | * vmci_qpair_peek() - Peek at the data in the queue. | |
3173 | * @qpair: Pointer to the queue pair struct. | |
3174 | * @buf: Pointer to buffer for the data | |
3175 | * @buf_size: Length of buffer. | |
3176 | * @buf_type: Buffer type (Unused on Linux). | |
3177 | * | |
3178 | * This is the client interface for peeking into a queue. (I.e., | |
3179 | * copy data from the queue without updating the head pointer.) | |
3180 | * Returns number of bytes dequeued or < 0 on error. | |
3181 | */ | |
3182 | ssize_t vmci_qpair_peek(struct vmci_qp *qpair, | |
3183 | void *buf, | |
3184 | size_t buf_size, | |
3185 | int buf_type) | |
3186 | { | |
3187 | ssize_t result; | |
3188 | ||
3189 | if (!qpair || !buf) | |
3190 | return VMCI_ERROR_INVALID_ARGS; | |
3191 | ||
3192 | qp_lock(qpair); | |
3193 | ||
3194 | do { | |
3195 | result = qp_dequeue_locked(qpair->produce_q, | |
3196 | qpair->consume_q, | |
3197 | qpair->consume_q_size, | |
3198 | buf, buf_size, | |
45412bef | 3199 | qp_memcpy_from_queue, false); |
06164d2b GZ |
3200 | |
3201 | if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY && | |
3202 | !qp_wait_for_ready_queue(qpair)) | |
3203 | result = VMCI_ERROR_WOULD_BLOCK; | |
3204 | ||
3205 | } while (result == VMCI_ERROR_QUEUEPAIR_NOT_READY); | |
3206 | ||
3207 | qp_unlock(qpair); | |
3208 | ||
3209 | return result; | |
3210 | } | |
3211 | EXPORT_SYMBOL_GPL(vmci_qpair_peek); | |
3212 | ||
3213 | /* | |
3214 | * vmci_qpair_enquev() - Throw data on the queue using iov. | |
3215 | * @qpair: Pointer to the queue pair struct. | |
3216 | * @iov: Pointer to buffer containing data | |
3217 | * @iov_size: Length of buffer. | |
3218 | * @buf_type: Buffer type (Unused). | |
3219 | * | |
3220 | * This is the client interface for enqueueing data into the queue. | |
3221 | * This function uses IO vectors to handle the work. Returns number | |
3222 | * of bytes enqueued or < 0 on error. | |
3223 | */ | |
3224 | ssize_t vmci_qpair_enquev(struct vmci_qp *qpair, | |
3225 | void *iov, | |
3226 | size_t iov_size, | |
3227 | int buf_type) | |
3228 | { | |
3229 | ssize_t result; | |
3230 | ||
3231 | if (!qpair || !iov) | |
3232 | return VMCI_ERROR_INVALID_ARGS; | |
3233 | ||
3234 | qp_lock(qpair); | |
3235 | ||
3236 | do { | |
3237 | result = qp_enqueue_locked(qpair->produce_q, | |
3238 | qpair->consume_q, | |
3239 | qpair->produce_q_size, | |
3240 | iov, iov_size, | |
45412bef | 3241 | qp_memcpy_to_queue_iov); |
06164d2b GZ |
3242 | |
3243 | if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY && | |
3244 | !qp_wait_for_ready_queue(qpair)) | |
3245 | result = VMCI_ERROR_WOULD_BLOCK; | |
3246 | ||
3247 | } while (result == VMCI_ERROR_QUEUEPAIR_NOT_READY); | |
3248 | ||
3249 | qp_unlock(qpair); | |
3250 | ||
3251 | return result; | |
3252 | } | |
3253 | EXPORT_SYMBOL_GPL(vmci_qpair_enquev); | |
3254 | ||
3255 | /* | |
3256 | * vmci_qpair_dequev() - Get data from the queue using iov. | |
3257 | * @qpair: Pointer to the queue pair struct. | |
3258 | * @iov: Pointer to buffer for the data | |
3259 | * @iov_size: Length of buffer. | |
3260 | * @buf_type: Buffer type (Unused). | |
3261 | * | |
3262 | * This is the client interface for dequeueing data from the queue. | |
3263 | * This function uses IO vectors to handle the work. Returns number | |
3264 | * of bytes dequeued or < 0 on error. | |
3265 | */ | |
3266 | ssize_t vmci_qpair_dequev(struct vmci_qp *qpair, | |
3267 | void *iov, | |
3268 | size_t iov_size, | |
3269 | int buf_type) | |
3270 | { | |
3271 | ssize_t result; | |
3272 | ||
06164d2b GZ |
3273 | if (!qpair || !iov) |
3274 | return VMCI_ERROR_INVALID_ARGS; | |
3275 | ||
32b083a3 AK |
3276 | qp_lock(qpair); |
3277 | ||
06164d2b GZ |
3278 | do { |
3279 | result = qp_dequeue_locked(qpair->produce_q, | |
3280 | qpair->consume_q, | |
3281 | qpair->consume_q_size, | |
3282 | iov, iov_size, | |
3283 | qp_memcpy_from_queue_iov, | |
45412bef | 3284 | true); |
06164d2b GZ |
3285 | |
3286 | if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY && | |
3287 | !qp_wait_for_ready_queue(qpair)) | |
3288 | result = VMCI_ERROR_WOULD_BLOCK; | |
3289 | ||
3290 | } while (result == VMCI_ERROR_QUEUEPAIR_NOT_READY); | |
3291 | ||
3292 | qp_unlock(qpair); | |
3293 | ||
3294 | return result; | |
3295 | } | |
3296 | EXPORT_SYMBOL_GPL(vmci_qpair_dequev); | |
3297 | ||
3298 | /* | |
3299 | * vmci_qpair_peekv() - Peek at the data in the queue using iov. | |
3300 | * @qpair: Pointer to the queue pair struct. | |
3301 | * @iov: Pointer to buffer for the data | |
3302 | * @iov_size: Length of buffer. | |
3303 | * @buf_type: Buffer type (Unused on Linux). | |
3304 | * | |
3305 | * This is the client interface for peeking into a queue. (I.e., | |
3306 | * copy data from the queue without updating the head pointer.) | |
3307 | * This function uses IO vectors to handle the work. Returns number | |
3308 | * of bytes peeked or < 0 on error. | |
3309 | */ | |
3310 | ssize_t vmci_qpair_peekv(struct vmci_qp *qpair, | |
3311 | void *iov, | |
3312 | size_t iov_size, | |
3313 | int buf_type) | |
3314 | { | |
3315 | ssize_t result; | |
3316 | ||
3317 | if (!qpair || !iov) | |
3318 | return VMCI_ERROR_INVALID_ARGS; | |
3319 | ||
3320 | qp_lock(qpair); | |
3321 | ||
3322 | do { | |
3323 | result = qp_dequeue_locked(qpair->produce_q, | |
3324 | qpair->consume_q, | |
3325 | qpair->consume_q_size, | |
3326 | iov, iov_size, | |
3327 | qp_memcpy_from_queue_iov, | |
45412bef | 3328 | false); |
06164d2b GZ |
3329 | |
3330 | if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY && | |
3331 | !qp_wait_for_ready_queue(qpair)) | |
3332 | result = VMCI_ERROR_WOULD_BLOCK; | |
3333 | ||
3334 | } while (result == VMCI_ERROR_QUEUEPAIR_NOT_READY); | |
3335 | ||
3336 | qp_unlock(qpair); | |
3337 | return result; | |
3338 | } | |
3339 | EXPORT_SYMBOL_GPL(vmci_qpair_peekv); |