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ad9a8612 JF |
1 | /****************************************************************************** |
2 | * grant_table.c | |
3 | * | |
4 | * Granting foreign access to our memory reservation. | |
5 | * | |
6 | * Copyright (c) 2005-2006, Christopher Clark | |
7 | * Copyright (c) 2004-2005, K A Fraser | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or | |
10 | * modify it under the terms of the GNU General Public License version 2 | |
11 | * as published by the Free Software Foundation; or, when distributed | |
12 | * separately from the Linux kernel or incorporated into other | |
13 | * software packages, subject to the following license: | |
14 | * | |
15 | * Permission is hereby granted, free of charge, to any person obtaining a copy | |
16 | * of this source file (the "Software"), to deal in the Software without | |
17 | * restriction, including without limitation the rights to use, copy, modify, | |
18 | * merge, publish, distribute, sublicense, and/or sell copies of the Software, | |
19 | * and to permit persons to whom the Software is furnished to do so, subject to | |
20 | * the following conditions: | |
21 | * | |
22 | * The above copyright notice and this permission notice shall be included in | |
23 | * all copies or substantial portions of the Software. | |
24 | * | |
25 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
26 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
27 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | |
28 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
29 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING | |
30 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS | |
31 | * IN THE SOFTWARE. | |
32 | */ | |
33 | ||
283c0972 JP |
34 | #define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt |
35 | ||
8dca4d96 | 36 | #include <linux/bootmem.h> |
ad9a8612 JF |
37 | #include <linux/sched.h> |
38 | #include <linux/mm.h> | |
5a0e3ad6 | 39 | #include <linux/slab.h> |
ad9a8612 JF |
40 | #include <linux/vmalloc.h> |
41 | #include <linux/uaccess.h> | |
183d03cc | 42 | #include <linux/io.h> |
c571898f | 43 | #include <linux/delay.h> |
f62805f1 | 44 | #include <linux/hardirq.h> |
3f9f1c67 | 45 | #include <linux/workqueue.h> |
29d11cfd | 46 | #include <linux/ratelimit.h> |
8dca4d96 | 47 | #include <linux/moduleparam.h> |
9bdc7304 OA |
48 | #ifdef CONFIG_XEN_GRANT_DMA_ALLOC |
49 | #include <linux/dma-mapping.h> | |
50 | #endif | |
ad9a8612 | 51 | |
1ccbf534 | 52 | #include <xen/xen.h> |
ad9a8612 JF |
53 | #include <xen/interface/xen.h> |
54 | #include <xen/page.h> | |
55 | #include <xen/grant_table.h> | |
183d03cc | 56 | #include <xen/interface/memory.h> |
85ff6acb | 57 | #include <xen/hvc-console.h> |
3d24bbd7 | 58 | #include <xen/swiotlb-xen.h> |
ff4b156f | 59 | #include <xen/balloon.h> |
8dca4d96 JG |
60 | #ifdef CONFIG_X86 |
61 | #include <asm/xen/cpuid.h> | |
62 | #endif | |
9bdc7304 | 63 | #include <xen/mem-reservation.h> |
ecbf29cd | 64 | #include <asm/xen/hypercall.h> |
4d9310e3 | 65 | #include <asm/xen/interface.h> |
ad9a8612 JF |
66 | |
67 | #include <asm/pgtable.h> | |
68 | #include <asm/sync_bitops.h> | |
69 | ||
ad9a8612 JF |
70 | /* External tools reserve first few grant table entries. */ |
71 | #define NR_RESERVED_ENTRIES 8 | |
72 | #define GNTTAB_LIST_END 0xffffffff | |
ad9a8612 JF |
73 | |
74 | static grant_ref_t **gnttab_list; | |
75 | static unsigned int nr_grant_frames; | |
ad9a8612 JF |
76 | static int gnttab_free_count; |
77 | static grant_ref_t gnttab_free_head; | |
78 | static DEFINE_SPINLOCK(gnttab_list_lock); | |
efaf30a3 | 79 | struct grant_frames xen_auto_xlat_grant_frames; |
8dca4d96 JG |
80 | static unsigned int xen_gnttab_version; |
81 | module_param_named(version, xen_gnttab_version, uint, 0); | |
ad9a8612 | 82 | |
0f9f5a95 AL |
83 | static union { |
84 | struct grant_entry_v1 *v1; | |
b988b8ff | 85 | union grant_entry_v2 *v2; |
0f9f5a95 AL |
86 | void *addr; |
87 | } gnttab_shared; | |
88 | ||
89 | /*This is a structure of function pointers for grant table*/ | |
90 | struct gnttab_ops { | |
83c69324 JG |
91 | /* |
92 | * Version of the grant interface. | |
93 | */ | |
94 | unsigned int version; | |
95 | /* | |
96 | * Grant refs per grant frame. | |
97 | */ | |
98 | unsigned int grefs_per_grant_frame; | |
0f9f5a95 | 99 | /* |
9dbc71d5 AL |
100 | * Mapping a list of frames for storing grant entries. Frames parameter |
101 | * is used to store grant table address when grant table being setup, | |
102 | * nr_gframes is the number of frames to map grant table. Returning | |
103 | * GNTST_okay means success and negative value means failure. | |
0f9f5a95 | 104 | */ |
ef32f892 | 105 | int (*map_frames)(xen_pfn_t *frames, unsigned int nr_gframes); |
0f9f5a95 AL |
106 | /* |
107 | * Release a list of frames which are mapped in map_frames for grant | |
108 | * entry status. | |
109 | */ | |
110 | void (*unmap_frames)(void); | |
111 | /* | |
9dbc71d5 AL |
112 | * Introducing a valid entry into the grant table, granting the frame of |
113 | * this grant entry to domain for accessing or transfering. Ref | |
114 | * parameter is reference of this introduced grant entry, domid is id of | |
115 | * granted domain, frame is the page frame to be granted, and flags is | |
116 | * status of the grant entry to be updated. | |
0f9f5a95 | 117 | */ |
9dbc71d5 AL |
118 | void (*update_entry)(grant_ref_t ref, domid_t domid, |
119 | unsigned long frame, unsigned flags); | |
0f9f5a95 | 120 | /* |
9dbc71d5 AL |
121 | * Stop granting a grant entry to domain for accessing. Ref parameter is |
122 | * reference of a grant entry whose grant access will be stopped, | |
123 | * readonly is not in use in this function. If the grant entry is | |
0f9f5a95 AL |
124 | * currently mapped for reading or writing, just return failure(==0) |
125 | * directly and don't tear down the grant access. Otherwise, stop grant | |
126 | * access for this entry and return success(==1). | |
127 | */ | |
9dbc71d5 | 128 | int (*end_foreign_access_ref)(grant_ref_t ref, int readonly); |
0f9f5a95 | 129 | /* |
9dbc71d5 AL |
130 | * Stop granting a grant entry to domain for transfer. Ref parameter is |
131 | * reference of a grant entry whose grant transfer will be stopped. If | |
132 | * tranfer has not started, just reclaim the grant entry and return | |
133 | * failure(==0). Otherwise, wait for the transfer to complete and then | |
134 | * return the frame. | |
0f9f5a95 | 135 | */ |
9dbc71d5 | 136 | unsigned long (*end_foreign_transfer_ref)(grant_ref_t ref); |
0f9f5a95 | 137 | /* |
9dbc71d5 | 138 | * Query the status of a grant entry. Ref parameter is reference of |
0f9f5a95 AL |
139 | * queried grant entry, return value is the status of queried entry. |
140 | * Detailed status(writing/reading) can be gotten from the return value | |
141 | * by bit operations. | |
142 | */ | |
9dbc71d5 | 143 | int (*query_foreign_access)(grant_ref_t ref); |
0f9f5a95 AL |
144 | }; |
145 | ||
b44166cd BL |
146 | struct unmap_refs_callback_data { |
147 | struct completion completion; | |
148 | int result; | |
149 | }; | |
150 | ||
86fc2136 | 151 | static const struct gnttab_ops *gnttab_interface; |
0f9f5a95 | 152 | |
b988b8ff JG |
153 | /* This reflects status of grant entries, so act as a global value. */ |
154 | static grant_status_t *grstatus; | |
ad9a8612 JF |
155 | |
156 | static struct gnttab_free_callback *gnttab_free_callback_list; | |
157 | ||
158 | static int gnttab_expand(unsigned int req_entries); | |
159 | ||
160 | #define RPP (PAGE_SIZE / sizeof(grant_ref_t)) | |
b988b8ff | 161 | #define SPP (PAGE_SIZE / sizeof(grant_status_t)) |
ad9a8612 JF |
162 | |
163 | static inline grant_ref_t *__gnttab_entry(grant_ref_t entry) | |
164 | { | |
165 | return &gnttab_list[(entry) / RPP][(entry) % RPP]; | |
166 | } | |
167 | /* This can be used as an l-value */ | |
168 | #define gnttab_entry(entry) (*__gnttab_entry(entry)) | |
169 | ||
170 | static int get_free_entries(unsigned count) | |
171 | { | |
172 | unsigned long flags; | |
272800dc | 173 | int ref, rc = 0; |
ad9a8612 JF |
174 | grant_ref_t head; |
175 | ||
176 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
177 | ||
178 | if ((gnttab_free_count < count) && | |
179 | ((rc = gnttab_expand(count - gnttab_free_count)) < 0)) { | |
180 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
181 | return rc; | |
182 | } | |
183 | ||
184 | ref = head = gnttab_free_head; | |
185 | gnttab_free_count -= count; | |
186 | while (count-- > 1) | |
187 | head = gnttab_entry(head); | |
188 | gnttab_free_head = gnttab_entry(head); | |
189 | gnttab_entry(head) = GNTTAB_LIST_END; | |
190 | ||
191 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
192 | ||
193 | return ref; | |
194 | } | |
195 | ||
196 | static void do_free_callbacks(void) | |
197 | { | |
198 | struct gnttab_free_callback *callback, *next; | |
199 | ||
200 | callback = gnttab_free_callback_list; | |
201 | gnttab_free_callback_list = NULL; | |
202 | ||
203 | while (callback != NULL) { | |
204 | next = callback->next; | |
205 | if (gnttab_free_count >= callback->count) { | |
206 | callback->next = NULL; | |
207 | callback->fn(callback->arg); | |
208 | } else { | |
209 | callback->next = gnttab_free_callback_list; | |
210 | gnttab_free_callback_list = callback; | |
211 | } | |
212 | callback = next; | |
213 | } | |
214 | } | |
215 | ||
216 | static inline void check_free_callbacks(void) | |
217 | { | |
218 | if (unlikely(gnttab_free_callback_list)) | |
219 | do_free_callbacks(); | |
220 | } | |
221 | ||
222 | static void put_free_entry(grant_ref_t ref) | |
223 | { | |
224 | unsigned long flags; | |
225 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
226 | gnttab_entry(ref) = gnttab_free_head; | |
227 | gnttab_free_head = ref; | |
228 | gnttab_free_count++; | |
229 | check_free_callbacks(); | |
230 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
231 | } | |
232 | ||
0f9f5a95 | 233 | /* |
b988b8ff | 234 | * Following applies to gnttab_update_entry_v1 and gnttab_update_entry_v2. |
0f9f5a95 AL |
235 | * Introducing a valid entry into the grant table: |
236 | * 1. Write ent->domid. | |
237 | * 2. Write ent->frame: | |
238 | * GTF_permit_access: Frame to which access is permitted. | |
239 | * GTF_accept_transfer: Pseudo-phys frame slot being filled by new | |
240 | * frame, or zero if none. | |
241 | * 3. Write memory barrier (WMB). | |
242 | * 4. Write ent->flags, inc. valid type. | |
243 | */ | |
244 | static void gnttab_update_entry_v1(grant_ref_t ref, domid_t domid, | |
245 | unsigned long frame, unsigned flags) | |
ad9a8612 | 246 | { |
0f9f5a95 AL |
247 | gnttab_shared.v1[ref].domid = domid; |
248 | gnttab_shared.v1[ref].frame = frame; | |
ad9a8612 | 249 | wmb(); |
0f9f5a95 | 250 | gnttab_shared.v1[ref].flags = flags; |
ad9a8612 JF |
251 | } |
252 | ||
b988b8ff JG |
253 | static void gnttab_update_entry_v2(grant_ref_t ref, domid_t domid, |
254 | unsigned long frame, unsigned int flags) | |
255 | { | |
256 | gnttab_shared.v2[ref].hdr.domid = domid; | |
257 | gnttab_shared.v2[ref].full_page.frame = frame; | |
258 | wmb(); /* Hypervisor concurrent accesses. */ | |
259 | gnttab_shared.v2[ref].hdr.flags = GTF_permit_access | flags; | |
260 | } | |
261 | ||
ad9a8612 JF |
262 | /* |
263 | * Public grant-issuing interface functions | |
264 | */ | |
265 | void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid, | |
266 | unsigned long frame, int readonly) | |
267 | { | |
0f9f5a95 | 268 | gnttab_interface->update_entry(ref, domid, frame, |
ad9a8612 JF |
269 | GTF_permit_access | (readonly ? GTF_readonly : 0)); |
270 | } | |
271 | EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_ref); | |
272 | ||
273 | int gnttab_grant_foreign_access(domid_t domid, unsigned long frame, | |
274 | int readonly) | |
275 | { | |
276 | int ref; | |
277 | ||
278 | ref = get_free_entries(1); | |
279 | if (unlikely(ref < 0)) | |
280 | return -ENOSPC; | |
281 | ||
282 | gnttab_grant_foreign_access_ref(ref, domid, frame, readonly); | |
283 | ||
284 | return ref; | |
285 | } | |
286 | EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access); | |
287 | ||
0f9f5a95 | 288 | static int gnttab_query_foreign_access_v1(grant_ref_t ref) |
ad9a8612 | 289 | { |
0f9f5a95 AL |
290 | return gnttab_shared.v1[ref].flags & (GTF_reading|GTF_writing); |
291 | } | |
ad9a8612 | 292 | |
b988b8ff JG |
293 | static int gnttab_query_foreign_access_v2(grant_ref_t ref) |
294 | { | |
295 | return grstatus[ref] & (GTF_reading|GTF_writing); | |
296 | } | |
297 | ||
0f9f5a95 AL |
298 | int gnttab_query_foreign_access(grant_ref_t ref) |
299 | { | |
300 | return gnttab_interface->query_foreign_access(ref); | |
ad9a8612 JF |
301 | } |
302 | EXPORT_SYMBOL_GPL(gnttab_query_foreign_access); | |
303 | ||
0f9f5a95 | 304 | static int gnttab_end_foreign_access_ref_v1(grant_ref_t ref, int readonly) |
ad9a8612 JF |
305 | { |
306 | u16 flags, nflags; | |
b1e495b2 | 307 | u16 *pflags; |
ad9a8612 | 308 | |
b1e495b2 AL |
309 | pflags = &gnttab_shared.v1[ref].flags; |
310 | nflags = *pflags; | |
ad9a8612 JF |
311 | do { |
312 | flags = nflags; | |
569ca5b3 | 313 | if (flags & (GTF_reading|GTF_writing)) |
ad9a8612 | 314 | return 0; |
b1e495b2 | 315 | } while ((nflags = sync_cmpxchg(pflags, flags, 0)) != flags); |
ad9a8612 JF |
316 | |
317 | return 1; | |
318 | } | |
0f9f5a95 | 319 | |
b988b8ff JG |
320 | static int gnttab_end_foreign_access_ref_v2(grant_ref_t ref, int readonly) |
321 | { | |
322 | gnttab_shared.v2[ref].hdr.flags = 0; | |
323 | mb(); /* Concurrent access by hypervisor. */ | |
324 | if (grstatus[ref] & (GTF_reading|GTF_writing)) { | |
325 | return 0; | |
326 | } else { | |
327 | /* | |
328 | * The read of grstatus needs to have acquire semantics. | |
329 | * On x86, reads already have that, and we just need to | |
330 | * protect against compiler reorderings. | |
331 | * On other architectures we may need a full barrier. | |
332 | */ | |
333 | #ifdef CONFIG_X86 | |
334 | barrier(); | |
335 | #else | |
336 | mb(); | |
337 | #endif | |
338 | } | |
339 | ||
340 | return 1; | |
341 | } | |
342 | ||
569ca5b3 | 343 | static inline int _gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly) |
0f9f5a95 AL |
344 | { |
345 | return gnttab_interface->end_foreign_access_ref(ref, readonly); | |
346 | } | |
569ca5b3 JB |
347 | |
348 | int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly) | |
349 | { | |
350 | if (_gnttab_end_foreign_access_ref(ref, readonly)) | |
351 | return 1; | |
352 | pr_warn("WARNING: g.e. %#x still in use!\n", ref); | |
353 | return 0; | |
354 | } | |
ad9a8612 JF |
355 | EXPORT_SYMBOL_GPL(gnttab_end_foreign_access_ref); |
356 | ||
569ca5b3 JB |
357 | struct deferred_entry { |
358 | struct list_head list; | |
359 | grant_ref_t ref; | |
360 | bool ro; | |
361 | uint16_t warn_delay; | |
362 | struct page *page; | |
363 | }; | |
364 | static LIST_HEAD(deferred_list); | |
24ed960a | 365 | static void gnttab_handle_deferred(struct timer_list *); |
1d27e3e2 | 366 | static DEFINE_TIMER(deferred_timer, gnttab_handle_deferred); |
569ca5b3 | 367 | |
24ed960a | 368 | static void gnttab_handle_deferred(struct timer_list *unused) |
569ca5b3 JB |
369 | { |
370 | unsigned int nr = 10; | |
371 | struct deferred_entry *first = NULL; | |
372 | unsigned long flags; | |
373 | ||
374 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
375 | while (nr--) { | |
376 | struct deferred_entry *entry | |
377 | = list_first_entry(&deferred_list, | |
378 | struct deferred_entry, list); | |
379 | ||
380 | if (entry == first) | |
381 | break; | |
382 | list_del(&entry->list); | |
383 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
384 | if (_gnttab_end_foreign_access_ref(entry->ref, entry->ro)) { | |
385 | put_free_entry(entry->ref); | |
386 | if (entry->page) { | |
387 | pr_debug("freeing g.e. %#x (pfn %#lx)\n", | |
388 | entry->ref, page_to_pfn(entry->page)); | |
3ac7292a | 389 | put_page(entry->page); |
569ca5b3 JB |
390 | } else |
391 | pr_info("freeing g.e. %#x\n", entry->ref); | |
392 | kfree(entry); | |
393 | entry = NULL; | |
394 | } else { | |
395 | if (!--entry->warn_delay) | |
283c0972 | 396 | pr_info("g.e. %#x still pending\n", entry->ref); |
569ca5b3 JB |
397 | if (!first) |
398 | first = entry; | |
399 | } | |
400 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
401 | if (entry) | |
402 | list_add_tail(&entry->list, &deferred_list); | |
403 | else if (list_empty(&deferred_list)) | |
404 | break; | |
405 | } | |
406 | if (!list_empty(&deferred_list) && !timer_pending(&deferred_timer)) { | |
407 | deferred_timer.expires = jiffies + HZ; | |
408 | add_timer(&deferred_timer); | |
409 | } | |
410 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
411 | } | |
412 | ||
413 | static void gnttab_add_deferred(grant_ref_t ref, bool readonly, | |
414 | struct page *page) | |
415 | { | |
416 | struct deferred_entry *entry = kmalloc(sizeof(*entry), GFP_ATOMIC); | |
417 | const char *what = KERN_WARNING "leaking"; | |
418 | ||
419 | if (entry) { | |
420 | unsigned long flags; | |
421 | ||
422 | entry->ref = ref; | |
423 | entry->ro = readonly; | |
424 | entry->page = page; | |
425 | entry->warn_delay = 60; | |
426 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
427 | list_add_tail(&entry->list, &deferred_list); | |
428 | if (!timer_pending(&deferred_timer)) { | |
429 | deferred_timer.expires = jiffies + HZ; | |
430 | add_timer(&deferred_timer); | |
431 | } | |
432 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
433 | what = KERN_DEBUG "deferring"; | |
434 | } | |
435 | printk("%s g.e. %#x (pfn %#lx)\n", | |
436 | what, ref, page ? page_to_pfn(page) : -1); | |
437 | } | |
438 | ||
ad9a8612 JF |
439 | void gnttab_end_foreign_access(grant_ref_t ref, int readonly, |
440 | unsigned long page) | |
441 | { | |
442 | if (gnttab_end_foreign_access_ref(ref, readonly)) { | |
443 | put_free_entry(ref); | |
444 | if (page != 0) | |
3ac7292a | 445 | put_page(virt_to_page(page)); |
569ca5b3 JB |
446 | } else |
447 | gnttab_add_deferred(ref, readonly, | |
448 | page ? virt_to_page(page) : NULL); | |
ad9a8612 JF |
449 | } |
450 | EXPORT_SYMBOL_GPL(gnttab_end_foreign_access); | |
451 | ||
452 | int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn) | |
453 | { | |
454 | int ref; | |
455 | ||
456 | ref = get_free_entries(1); | |
457 | if (unlikely(ref < 0)) | |
458 | return -ENOSPC; | |
459 | gnttab_grant_foreign_transfer_ref(ref, domid, pfn); | |
460 | ||
461 | return ref; | |
462 | } | |
463 | EXPORT_SYMBOL_GPL(gnttab_grant_foreign_transfer); | |
464 | ||
465 | void gnttab_grant_foreign_transfer_ref(grant_ref_t ref, domid_t domid, | |
466 | unsigned long pfn) | |
467 | { | |
0f9f5a95 | 468 | gnttab_interface->update_entry(ref, domid, pfn, GTF_accept_transfer); |
ad9a8612 JF |
469 | } |
470 | EXPORT_SYMBOL_GPL(gnttab_grant_foreign_transfer_ref); | |
471 | ||
0f9f5a95 | 472 | static unsigned long gnttab_end_foreign_transfer_ref_v1(grant_ref_t ref) |
ad9a8612 JF |
473 | { |
474 | unsigned long frame; | |
475 | u16 flags; | |
b1e495b2 AL |
476 | u16 *pflags; |
477 | ||
478 | pflags = &gnttab_shared.v1[ref].flags; | |
ad9a8612 JF |
479 | |
480 | /* | |
481 | * If a transfer is not even yet started, try to reclaim the grant | |
482 | * reference and return failure (== 0). | |
483 | */ | |
b1e495b2 AL |
484 | while (!((flags = *pflags) & GTF_transfer_committed)) { |
485 | if (sync_cmpxchg(pflags, flags, 0) == flags) | |
ad9a8612 JF |
486 | return 0; |
487 | cpu_relax(); | |
488 | } | |
489 | ||
490 | /* If a transfer is in progress then wait until it is completed. */ | |
491 | while (!(flags & GTF_transfer_completed)) { | |
b1e495b2 | 492 | flags = *pflags; |
ad9a8612 JF |
493 | cpu_relax(); |
494 | } | |
495 | ||
496 | rmb(); /* Read the frame number /after/ reading completion status. */ | |
0f9f5a95 | 497 | frame = gnttab_shared.v1[ref].frame; |
ad9a8612 JF |
498 | BUG_ON(frame == 0); |
499 | ||
500 | return frame; | |
501 | } | |
0f9f5a95 | 502 | |
b988b8ff JG |
503 | static unsigned long gnttab_end_foreign_transfer_ref_v2(grant_ref_t ref) |
504 | { | |
505 | unsigned long frame; | |
506 | u16 flags; | |
507 | u16 *pflags; | |
508 | ||
509 | pflags = &gnttab_shared.v2[ref].hdr.flags; | |
510 | ||
511 | /* | |
512 | * If a transfer is not even yet started, try to reclaim the grant | |
513 | * reference and return failure (== 0). | |
514 | */ | |
515 | while (!((flags = *pflags) & GTF_transfer_committed)) { | |
516 | if (sync_cmpxchg(pflags, flags, 0) == flags) | |
517 | return 0; | |
518 | cpu_relax(); | |
519 | } | |
520 | ||
521 | /* If a transfer is in progress then wait until it is completed. */ | |
522 | while (!(flags & GTF_transfer_completed)) { | |
523 | flags = *pflags; | |
524 | cpu_relax(); | |
525 | } | |
526 | ||
527 | rmb(); /* Read the frame number /after/ reading completion status. */ | |
528 | frame = gnttab_shared.v2[ref].full_page.frame; | |
529 | BUG_ON(frame == 0); | |
530 | ||
531 | return frame; | |
532 | } | |
533 | ||
0f9f5a95 AL |
534 | unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref) |
535 | { | |
536 | return gnttab_interface->end_foreign_transfer_ref(ref); | |
537 | } | |
ad9a8612 JF |
538 | EXPORT_SYMBOL_GPL(gnttab_end_foreign_transfer_ref); |
539 | ||
540 | unsigned long gnttab_end_foreign_transfer(grant_ref_t ref) | |
541 | { | |
542 | unsigned long frame = gnttab_end_foreign_transfer_ref(ref); | |
543 | put_free_entry(ref); | |
544 | return frame; | |
545 | } | |
546 | EXPORT_SYMBOL_GPL(gnttab_end_foreign_transfer); | |
547 | ||
548 | void gnttab_free_grant_reference(grant_ref_t ref) | |
549 | { | |
550 | put_free_entry(ref); | |
551 | } | |
552 | EXPORT_SYMBOL_GPL(gnttab_free_grant_reference); | |
553 | ||
554 | void gnttab_free_grant_references(grant_ref_t head) | |
555 | { | |
556 | grant_ref_t ref; | |
557 | unsigned long flags; | |
558 | int count = 1; | |
559 | if (head == GNTTAB_LIST_END) | |
560 | return; | |
561 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
562 | ref = head; | |
563 | while (gnttab_entry(ref) != GNTTAB_LIST_END) { | |
564 | ref = gnttab_entry(ref); | |
565 | count++; | |
566 | } | |
567 | gnttab_entry(ref) = gnttab_free_head; | |
568 | gnttab_free_head = head; | |
569 | gnttab_free_count += count; | |
570 | check_free_callbacks(); | |
571 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
572 | } | |
573 | EXPORT_SYMBOL_GPL(gnttab_free_grant_references); | |
574 | ||
575 | int gnttab_alloc_grant_references(u16 count, grant_ref_t *head) | |
576 | { | |
577 | int h = get_free_entries(count); | |
578 | ||
579 | if (h < 0) | |
580 | return -ENOSPC; | |
581 | ||
582 | *head = h; | |
583 | ||
584 | return 0; | |
585 | } | |
586 | EXPORT_SYMBOL_GPL(gnttab_alloc_grant_references); | |
587 | ||
588 | int gnttab_empty_grant_references(const grant_ref_t *private_head) | |
589 | { | |
590 | return (*private_head == GNTTAB_LIST_END); | |
591 | } | |
592 | EXPORT_SYMBOL_GPL(gnttab_empty_grant_references); | |
593 | ||
594 | int gnttab_claim_grant_reference(grant_ref_t *private_head) | |
595 | { | |
596 | grant_ref_t g = *private_head; | |
597 | if (unlikely(g == GNTTAB_LIST_END)) | |
598 | return -ENOSPC; | |
599 | *private_head = gnttab_entry(g); | |
600 | return g; | |
601 | } | |
602 | EXPORT_SYMBOL_GPL(gnttab_claim_grant_reference); | |
603 | ||
604 | void gnttab_release_grant_reference(grant_ref_t *private_head, | |
605 | grant_ref_t release) | |
606 | { | |
607 | gnttab_entry(release) = *private_head; | |
608 | *private_head = release; | |
609 | } | |
610 | EXPORT_SYMBOL_GPL(gnttab_release_grant_reference); | |
611 | ||
612 | void gnttab_request_free_callback(struct gnttab_free_callback *callback, | |
613 | void (*fn)(void *), void *arg, u16 count) | |
614 | { | |
615 | unsigned long flags; | |
5f338d90 RPM |
616 | struct gnttab_free_callback *cb; |
617 | ||
ad9a8612 | 618 | spin_lock_irqsave(&gnttab_list_lock, flags); |
5f338d90 RPM |
619 | |
620 | /* Check if the callback is already on the list */ | |
621 | cb = gnttab_free_callback_list; | |
622 | while (cb) { | |
623 | if (cb == callback) | |
624 | goto out; | |
625 | cb = cb->next; | |
626 | } | |
627 | ||
ad9a8612 JF |
628 | callback->fn = fn; |
629 | callback->arg = arg; | |
630 | callback->count = count; | |
631 | callback->next = gnttab_free_callback_list; | |
632 | gnttab_free_callback_list = callback; | |
633 | check_free_callbacks(); | |
634 | out: | |
635 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
636 | } | |
637 | EXPORT_SYMBOL_GPL(gnttab_request_free_callback); | |
638 | ||
639 | void gnttab_cancel_free_callback(struct gnttab_free_callback *callback) | |
640 | { | |
641 | struct gnttab_free_callback **pcb; | |
642 | unsigned long flags; | |
643 | ||
644 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
645 | for (pcb = &gnttab_free_callback_list; *pcb; pcb = &(*pcb)->next) { | |
646 | if (*pcb == callback) { | |
647 | *pcb = callback->next; | |
648 | break; | |
649 | } | |
650 | } | |
651 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
652 | } | |
653 | EXPORT_SYMBOL_GPL(gnttab_cancel_free_callback); | |
654 | ||
83c69324 JG |
655 | static unsigned int gnttab_frames(unsigned int frames, unsigned int align) |
656 | { | |
657 | return (frames * gnttab_interface->grefs_per_grant_frame + align - 1) / | |
658 | align; | |
659 | } | |
660 | ||
ad9a8612 JF |
661 | static int grow_gnttab_list(unsigned int more_frames) |
662 | { | |
663 | unsigned int new_nr_grant_frames, extra_entries, i; | |
bbc60c18 | 664 | unsigned int nr_glist_frames, new_nr_glist_frames; |
83c69324 | 665 | unsigned int grefs_per_frame; |
ad9a8612 | 666 | |
83c69324 JG |
667 | BUG_ON(gnttab_interface == NULL); |
668 | grefs_per_frame = gnttab_interface->grefs_per_grant_frame; | |
d0b4d64a | 669 | |
ad9a8612 | 670 | new_nr_grant_frames = nr_grant_frames + more_frames; |
83c69324 | 671 | extra_entries = more_frames * grefs_per_frame; |
ad9a8612 | 672 | |
83c69324 JG |
673 | nr_glist_frames = gnttab_frames(nr_grant_frames, RPP); |
674 | new_nr_glist_frames = gnttab_frames(new_nr_grant_frames, RPP); | |
bbc60c18 | 675 | for (i = nr_glist_frames; i < new_nr_glist_frames; i++) { |
ad9a8612 JF |
676 | gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_ATOMIC); |
677 | if (!gnttab_list[i]) | |
678 | goto grow_nomem; | |
679 | } | |
680 | ||
681 | ||
83c69324 JG |
682 | for (i = grefs_per_frame * nr_grant_frames; |
683 | i < grefs_per_frame * new_nr_grant_frames - 1; i++) | |
ad9a8612 JF |
684 | gnttab_entry(i) = i + 1; |
685 | ||
686 | gnttab_entry(i) = gnttab_free_head; | |
83c69324 | 687 | gnttab_free_head = grefs_per_frame * nr_grant_frames; |
ad9a8612 JF |
688 | gnttab_free_count += extra_entries; |
689 | ||
690 | nr_grant_frames = new_nr_grant_frames; | |
691 | ||
692 | check_free_callbacks(); | |
693 | ||
694 | return 0; | |
695 | ||
696 | grow_nomem: | |
46e3626a | 697 | while (i-- > nr_glist_frames) |
ad9a8612 JF |
698 | free_page((unsigned long) gnttab_list[i]); |
699 | return -ENOMEM; | |
700 | } | |
701 | ||
702 | static unsigned int __max_nr_grant_frames(void) | |
703 | { | |
704 | struct gnttab_query_size query; | |
705 | int rc; | |
706 | ||
707 | query.dom = DOMID_SELF; | |
708 | ||
709 | rc = HYPERVISOR_grant_table_op(GNTTABOP_query_size, &query, 1); | |
710 | if ((rc < 0) || (query.status != GNTST_okay)) | |
711 | return 4; /* Legacy max supported number of frames */ | |
712 | ||
713 | return query.max_nr_frames; | |
714 | } | |
715 | ||
183d03cc | 716 | unsigned int gnttab_max_grant_frames(void) |
ad9a8612 JF |
717 | { |
718 | unsigned int xen_max = __max_nr_grant_frames(); | |
7f256020 KRW |
719 | static unsigned int boot_max_nr_grant_frames; |
720 | ||
721 | /* First time, initialize it properly. */ | |
722 | if (!boot_max_nr_grant_frames) | |
723 | boot_max_nr_grant_frames = __max_nr_grant_frames(); | |
ad9a8612 JF |
724 | |
725 | if (xen_max > boot_max_nr_grant_frames) | |
726 | return boot_max_nr_grant_frames; | |
727 | return xen_max; | |
728 | } | |
183d03cc | 729 | EXPORT_SYMBOL_GPL(gnttab_max_grant_frames); |
ad9a8612 | 730 | |
47c54205 | 731 | int gnttab_setup_auto_xlat_frames(phys_addr_t addr) |
efaf30a3 KRW |
732 | { |
733 | xen_pfn_t *pfn; | |
734 | unsigned int max_nr_gframes = __max_nr_grant_frames(); | |
735 | unsigned int i; | |
736 | void *vaddr; | |
737 | ||
738 | if (xen_auto_xlat_grant_frames.count) | |
739 | return -EINVAL; | |
740 | ||
5ed5451d | 741 | vaddr = xen_remap(addr, XEN_PAGE_SIZE * max_nr_gframes); |
efaf30a3 | 742 | if (vaddr == NULL) { |
47c54205 JG |
743 | pr_warn("Failed to ioremap gnttab share frames (addr=%pa)!\n", |
744 | &addr); | |
efaf30a3 KRW |
745 | return -ENOMEM; |
746 | } | |
747 | pfn = kcalloc(max_nr_gframes, sizeof(pfn[0]), GFP_KERNEL); | |
748 | if (!pfn) { | |
749 | xen_unmap(vaddr); | |
750 | return -ENOMEM; | |
751 | } | |
752 | for (i = 0; i < max_nr_gframes; i++) | |
5ed5451d | 753 | pfn[i] = XEN_PFN_DOWN(addr) + i; |
efaf30a3 KRW |
754 | |
755 | xen_auto_xlat_grant_frames.vaddr = vaddr; | |
756 | xen_auto_xlat_grant_frames.pfn = pfn; | |
757 | xen_auto_xlat_grant_frames.count = max_nr_gframes; | |
758 | ||
759 | return 0; | |
760 | } | |
761 | EXPORT_SYMBOL_GPL(gnttab_setup_auto_xlat_frames); | |
762 | ||
763 | void gnttab_free_auto_xlat_frames(void) | |
764 | { | |
765 | if (!xen_auto_xlat_grant_frames.count) | |
766 | return; | |
767 | kfree(xen_auto_xlat_grant_frames.pfn); | |
768 | xen_unmap(xen_auto_xlat_grant_frames.vaddr); | |
769 | ||
770 | xen_auto_xlat_grant_frames.pfn = NULL; | |
771 | xen_auto_xlat_grant_frames.count = 0; | |
772 | xen_auto_xlat_grant_frames.vaddr = NULL; | |
773 | } | |
774 | EXPORT_SYMBOL_GPL(gnttab_free_auto_xlat_frames); | |
775 | ||
8c3799ee | 776 | int gnttab_pages_set_private(int nr_pages, struct page **pages) |
ff4b156f | 777 | { |
8da7633f | 778 | int i; |
ff4b156f | 779 | |
8da7633f JH |
780 | for (i = 0; i < nr_pages; i++) { |
781 | #if BITS_PER_LONG < 64 | |
782 | struct xen_page_foreign *foreign; | |
783 | ||
784 | foreign = kzalloc(sizeof(*foreign), GFP_KERNEL); | |
8c3799ee | 785 | if (!foreign) |
8da7633f | 786 | return -ENOMEM; |
8c3799ee | 787 | |
8da7633f JH |
788 | set_page_private(pages[i], (unsigned long)foreign); |
789 | #endif | |
790 | SetPagePrivate(pages[i]); | |
791 | } | |
792 | ||
ff4b156f DV |
793 | return 0; |
794 | } | |
8c3799ee | 795 | EXPORT_SYMBOL_GPL(gnttab_pages_set_private); |
ff4b156f DV |
796 | |
797 | /** | |
8c3799ee OA |
798 | * gnttab_alloc_pages - alloc pages suitable for grant mapping into |
799 | * @nr_pages: number of pages to alloc | |
800 | * @pages: returns the pages | |
ff4b156f | 801 | */ |
8c3799ee OA |
802 | int gnttab_alloc_pages(int nr_pages, struct page **pages) |
803 | { | |
804 | int ret; | |
805 | ||
806 | ret = alloc_xenballooned_pages(nr_pages, pages); | |
807 | if (ret < 0) | |
808 | return ret; | |
809 | ||
810 | ret = gnttab_pages_set_private(nr_pages, pages); | |
811 | if (ret < 0) | |
812 | gnttab_free_pages(nr_pages, pages); | |
813 | ||
814 | return ret; | |
815 | } | |
816 | EXPORT_SYMBOL_GPL(gnttab_alloc_pages); | |
817 | ||
818 | void gnttab_pages_clear_private(int nr_pages, struct page **pages) | |
ff4b156f | 819 | { |
8da7633f JH |
820 | int i; |
821 | ||
822 | for (i = 0; i < nr_pages; i++) { | |
823 | if (PagePrivate(pages[i])) { | |
824 | #if BITS_PER_LONG < 64 | |
825 | kfree((void *)page_private(pages[i])); | |
826 | #endif | |
827 | ClearPagePrivate(pages[i]); | |
828 | } | |
829 | } | |
8c3799ee OA |
830 | } |
831 | EXPORT_SYMBOL_GPL(gnttab_pages_clear_private); | |
832 | ||
833 | /** | |
834 | * gnttab_free_pages - free pages allocated by gnttab_alloc_pages() | |
835 | * @nr_pages; number of pages to free | |
836 | * @pages: the pages | |
837 | */ | |
838 | void gnttab_free_pages(int nr_pages, struct page **pages) | |
839 | { | |
840 | gnttab_pages_clear_private(nr_pages, pages); | |
ff4b156f DV |
841 | free_xenballooned_pages(nr_pages, pages); |
842 | } | |
6e3cc2a6 | 843 | EXPORT_SYMBOL_GPL(gnttab_free_pages); |
ff4b156f | 844 | |
9bdc7304 OA |
845 | #ifdef CONFIG_XEN_GRANT_DMA_ALLOC |
846 | /** | |
847 | * gnttab_dma_alloc_pages - alloc DMAable pages suitable for grant mapping into | |
848 | * @args: arguments to the function | |
849 | */ | |
850 | int gnttab_dma_alloc_pages(struct gnttab_dma_alloc_args *args) | |
851 | { | |
852 | unsigned long pfn, start_pfn; | |
853 | size_t size; | |
854 | int i, ret; | |
855 | ||
856 | size = args->nr_pages << PAGE_SHIFT; | |
857 | if (args->coherent) | |
858 | args->vaddr = dma_alloc_coherent(args->dev, size, | |
859 | &args->dev_bus_addr, | |
860 | GFP_KERNEL | __GFP_NOWARN); | |
861 | else | |
862 | args->vaddr = dma_alloc_wc(args->dev, size, | |
863 | &args->dev_bus_addr, | |
864 | GFP_KERNEL | __GFP_NOWARN); | |
865 | if (!args->vaddr) { | |
866 | pr_debug("Failed to allocate DMA buffer of size %zu\n", size); | |
867 | return -ENOMEM; | |
868 | } | |
869 | ||
870 | start_pfn = __phys_to_pfn(args->dev_bus_addr); | |
871 | for (pfn = start_pfn, i = 0; pfn < start_pfn + args->nr_pages; | |
872 | pfn++, i++) { | |
873 | struct page *page = pfn_to_page(pfn); | |
874 | ||
875 | args->pages[i] = page; | |
876 | args->frames[i] = xen_page_to_gfn(page); | |
877 | xenmem_reservation_scrub_page(page); | |
878 | } | |
879 | ||
880 | xenmem_reservation_va_mapping_reset(args->nr_pages, args->pages); | |
881 | ||
882 | ret = xenmem_reservation_decrease(args->nr_pages, args->frames); | |
883 | if (ret != args->nr_pages) { | |
884 | pr_debug("Failed to decrease reservation for DMA buffer\n"); | |
885 | ret = -EFAULT; | |
886 | goto fail; | |
887 | } | |
888 | ||
889 | ret = gnttab_pages_set_private(args->nr_pages, args->pages); | |
890 | if (ret < 0) | |
891 | goto fail; | |
892 | ||
893 | return 0; | |
894 | ||
895 | fail: | |
896 | gnttab_dma_free_pages(args); | |
897 | return ret; | |
898 | } | |
899 | EXPORT_SYMBOL_GPL(gnttab_dma_alloc_pages); | |
900 | ||
901 | /** | |
902 | * gnttab_dma_free_pages - free DMAable pages | |
903 | * @args: arguments to the function | |
904 | */ | |
905 | int gnttab_dma_free_pages(struct gnttab_dma_alloc_args *args) | |
906 | { | |
907 | size_t size; | |
908 | int i, ret; | |
909 | ||
910 | gnttab_pages_clear_private(args->nr_pages, args->pages); | |
911 | ||
912 | for (i = 0; i < args->nr_pages; i++) | |
913 | args->frames[i] = page_to_xen_pfn(args->pages[i]); | |
914 | ||
915 | ret = xenmem_reservation_increase(args->nr_pages, args->frames); | |
916 | if (ret != args->nr_pages) { | |
917 | pr_debug("Failed to decrease reservation for DMA buffer\n"); | |
918 | ret = -EFAULT; | |
919 | } else { | |
920 | ret = 0; | |
921 | } | |
922 | ||
923 | xenmem_reservation_va_mapping_update(args->nr_pages, args->pages, | |
924 | args->frames); | |
925 | ||
926 | size = args->nr_pages << PAGE_SHIFT; | |
927 | if (args->coherent) | |
928 | dma_free_coherent(args->dev, size, | |
929 | args->vaddr, args->dev_bus_addr); | |
930 | else | |
931 | dma_free_wc(args->dev, size, | |
932 | args->vaddr, args->dev_bus_addr); | |
933 | return ret; | |
934 | } | |
935 | EXPORT_SYMBOL_GPL(gnttab_dma_free_pages); | |
936 | #endif | |
937 | ||
c571898f ALC |
938 | /* Handling of paged out grant targets (GNTST_eagain) */ |
939 | #define MAX_DELAY 256 | |
940 | static inline void | |
941 | gnttab_retry_eagain_gop(unsigned int cmd, void *gop, int16_t *status, | |
942 | const char *func) | |
943 | { | |
944 | unsigned delay = 1; | |
945 | ||
946 | do { | |
947 | BUG_ON(HYPERVISOR_grant_table_op(cmd, gop, 1)); | |
948 | if (*status == GNTST_eagain) | |
949 | msleep(delay++); | |
950 | } while ((*status == GNTST_eagain) && (delay < MAX_DELAY)); | |
951 | ||
952 | if (delay >= MAX_DELAY) { | |
283c0972 | 953 | pr_err("%s: %s eagain grant\n", func, current->comm); |
c571898f ALC |
954 | *status = GNTST_bad_page; |
955 | } | |
956 | } | |
957 | ||
958 | void gnttab_batch_map(struct gnttab_map_grant_ref *batch, unsigned count) | |
959 | { | |
960 | struct gnttab_map_grant_ref *op; | |
961 | ||
962 | if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, batch, count)) | |
963 | BUG(); | |
964 | for (op = batch; op < batch + count; op++) | |
965 | if (op->status == GNTST_eagain) | |
966 | gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref, op, | |
967 | &op->status, __func__); | |
968 | } | |
969 | EXPORT_SYMBOL_GPL(gnttab_batch_map); | |
970 | ||
971 | void gnttab_batch_copy(struct gnttab_copy *batch, unsigned count) | |
972 | { | |
973 | struct gnttab_copy *op; | |
974 | ||
975 | if (HYPERVISOR_grant_table_op(GNTTABOP_copy, batch, count)) | |
976 | BUG(); | |
977 | for (op = batch; op < batch + count; op++) | |
978 | if (op->status == GNTST_eagain) | |
979 | gnttab_retry_eagain_gop(GNTTABOP_copy, op, | |
980 | &op->status, __func__); | |
981 | } | |
982 | EXPORT_SYMBOL_GPL(gnttab_batch_copy); | |
983 | ||
008c320a JG |
984 | void gnttab_foreach_grant_in_range(struct page *page, |
985 | unsigned int offset, | |
986 | unsigned int len, | |
987 | xen_grant_fn_t fn, | |
988 | void *data) | |
989 | { | |
990 | unsigned int goffset; | |
991 | unsigned int glen; | |
992 | unsigned long xen_pfn; | |
993 | ||
994 | len = min_t(unsigned int, PAGE_SIZE - offset, len); | |
995 | goffset = xen_offset_in_page(offset); | |
996 | ||
997 | xen_pfn = page_to_xen_pfn(page) + XEN_PFN_DOWN(offset); | |
998 | ||
999 | while (len) { | |
1000 | glen = min_t(unsigned int, XEN_PAGE_SIZE - goffset, len); | |
1001 | fn(pfn_to_gfn(xen_pfn), goffset, glen, data); | |
1002 | ||
1003 | goffset = 0; | |
1004 | xen_pfn++; | |
1005 | len -= glen; | |
1006 | } | |
1007 | } | |
1008 | EXPORT_SYMBOL_GPL(gnttab_foreach_grant_in_range); | |
1009 | ||
f73314b2 JG |
1010 | void gnttab_foreach_grant(struct page **pages, |
1011 | unsigned int nr_grefs, | |
1012 | xen_grant_fn_t fn, | |
1013 | void *data) | |
1014 | { | |
1015 | unsigned int goffset = 0; | |
1016 | unsigned long xen_pfn = 0; | |
1017 | unsigned int i; | |
1018 | ||
1019 | for (i = 0; i < nr_grefs; i++) { | |
1020 | if ((i % XEN_PFN_PER_PAGE) == 0) { | |
1021 | xen_pfn = page_to_xen_pfn(pages[i / XEN_PFN_PER_PAGE]); | |
1022 | goffset = 0; | |
1023 | } | |
1024 | ||
1025 | fn(pfn_to_gfn(xen_pfn), goffset, XEN_PAGE_SIZE, data); | |
1026 | ||
1027 | goffset += XEN_PAGE_SIZE; | |
1028 | xen_pfn++; | |
1029 | } | |
1030 | } | |
1031 | ||
e85fc980 | 1032 | int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, |
c123799a | 1033 | struct gnttab_map_grant_ref *kmap_ops, |
e85fc980 | 1034 | struct page **pages, unsigned int count) |
289b777e SS |
1035 | { |
1036 | int i, ret; | |
289b777e SS |
1037 | |
1038 | ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, map_ops, count); | |
87f1d40a JF |
1039 | if (ret) |
1040 | return ret; | |
289b777e | 1041 | |
8da7633f | 1042 | for (i = 0; i < count; i++) { |
d59f5324 JG |
1043 | switch (map_ops[i].status) { |
1044 | case GNTST_okay: | |
1045 | { | |
8da7633f JH |
1046 | struct xen_page_foreign *foreign; |
1047 | ||
1048 | SetPageForeign(pages[i]); | |
1049 | foreign = xen_page_foreign(pages[i]); | |
1050 | foreign->domid = map_ops[i].dom; | |
1051 | foreign->gref = map_ops[i].ref; | |
d59f5324 JG |
1052 | break; |
1053 | } | |
1054 | ||
1055 | case GNTST_no_device_space: | |
1056 | pr_warn_ratelimited("maptrack limit reached, can't map all guest pages\n"); | |
1057 | break; | |
1058 | ||
1059 | case GNTST_eagain: | |
1060 | /* Retry eagain maps */ | |
1061 | gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref, | |
1062 | map_ops + i, | |
1063 | &map_ops[i].status, __func__); | |
1064 | /* Test status in next loop iteration. */ | |
1065 | i--; | |
1066 | break; | |
1067 | ||
1068 | default: | |
1069 | break; | |
8da7633f JH |
1070 | } |
1071 | } | |
1072 | ||
1429d46d | 1073 | return set_foreign_p2m_mapping(map_ops, kmap_ops, pages, count); |
289b777e SS |
1074 | } |
1075 | EXPORT_SYMBOL_GPL(gnttab_map_refs); | |
1076 | ||
e85fc980 | 1077 | int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops, |
853d0289 | 1078 | struct gnttab_unmap_grant_ref *kunmap_ops, |
e85fc980 | 1079 | struct page **pages, unsigned int count) |
289b777e | 1080 | { |
8da7633f | 1081 | unsigned int i; |
1429d46d | 1082 | int ret; |
289b777e SS |
1083 | |
1084 | ret = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap_ops, count); | |
87f1d40a JF |
1085 | if (ret) |
1086 | return ret; | |
1087 | ||
8da7633f JH |
1088 | for (i = 0; i < count; i++) |
1089 | ClearPageForeign(pages[i]); | |
1090 | ||
853d0289 | 1091 | return clear_foreign_p2m_mapping(unmap_ops, kunmap_ops, pages, count); |
289b777e SS |
1092 | } |
1093 | EXPORT_SYMBOL_GPL(gnttab_unmap_refs); | |
1094 | ||
3f9f1c67 JH |
1095 | #define GNTTAB_UNMAP_REFS_DELAY 5 |
1096 | ||
1097 | static void __gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item); | |
1098 | ||
1099 | static void gnttab_unmap_work(struct work_struct *work) | |
1100 | { | |
1101 | struct gntab_unmap_queue_data | |
1102 | *unmap_data = container_of(work, | |
1103 | struct gntab_unmap_queue_data, | |
1104 | gnttab_work.work); | |
1105 | if (unmap_data->age != UINT_MAX) | |
1106 | unmap_data->age++; | |
1107 | __gnttab_unmap_refs_async(unmap_data); | |
1108 | } | |
1109 | ||
1110 | static void __gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item) | |
1111 | { | |
1112 | int ret; | |
1113 | int pc; | |
1114 | ||
1115 | for (pc = 0; pc < item->count; pc++) { | |
1116 | if (page_count(item->pages[pc]) > 1) { | |
1117 | unsigned long delay = GNTTAB_UNMAP_REFS_DELAY * (item->age + 1); | |
1118 | schedule_delayed_work(&item->gnttab_work, | |
1119 | msecs_to_jiffies(delay)); | |
1120 | return; | |
1121 | } | |
1122 | } | |
1123 | ||
1124 | ret = gnttab_unmap_refs(item->unmap_ops, item->kunmap_ops, | |
1125 | item->pages, item->count); | |
1126 | item->done(ret, item); | |
1127 | } | |
1128 | ||
1129 | void gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item) | |
1130 | { | |
1131 | INIT_DELAYED_WORK(&item->gnttab_work, gnttab_unmap_work); | |
1132 | item->age = 0; | |
1133 | ||
1134 | __gnttab_unmap_refs_async(item); | |
1135 | } | |
1136 | EXPORT_SYMBOL_GPL(gnttab_unmap_refs_async); | |
1137 | ||
b44166cd BL |
1138 | static void unmap_refs_callback(int result, |
1139 | struct gntab_unmap_queue_data *data) | |
1140 | { | |
1141 | struct unmap_refs_callback_data *d = data->data; | |
1142 | ||
1143 | d->result = result; | |
1144 | complete(&d->completion); | |
1145 | } | |
1146 | ||
1147 | int gnttab_unmap_refs_sync(struct gntab_unmap_queue_data *item) | |
1148 | { | |
1149 | struct unmap_refs_callback_data data; | |
1150 | ||
1151 | init_completion(&data.completion); | |
1152 | item->data = &data; | |
1153 | item->done = &unmap_refs_callback; | |
1154 | gnttab_unmap_refs_async(item); | |
1155 | wait_for_completion(&data.completion); | |
1156 | ||
1157 | return data.result; | |
1158 | } | |
1159 | EXPORT_SYMBOL_GPL(gnttab_unmap_refs_sync); | |
1160 | ||
b988b8ff JG |
1161 | static unsigned int nr_status_frames(unsigned int nr_grant_frames) |
1162 | { | |
83c69324 JG |
1163 | BUG_ON(gnttab_interface == NULL); |
1164 | return gnttab_frames(nr_grant_frames, SPP); | |
b988b8ff JG |
1165 | } |
1166 | ||
ef32f892 | 1167 | static int gnttab_map_frames_v1(xen_pfn_t *frames, unsigned int nr_gframes) |
0f9f5a95 AL |
1168 | { |
1169 | int rc; | |
1170 | ||
1171 | rc = arch_gnttab_map_shared(frames, nr_gframes, | |
1172 | gnttab_max_grant_frames(), | |
1173 | &gnttab_shared.addr); | |
1174 | BUG_ON(rc); | |
1175 | ||
1176 | return 0; | |
1177 | } | |
1178 | ||
1179 | static void gnttab_unmap_frames_v1(void) | |
1180 | { | |
85ff6acb AL |
1181 | arch_gnttab_unmap(gnttab_shared.addr, nr_grant_frames); |
1182 | } | |
1183 | ||
b988b8ff JG |
1184 | static int gnttab_map_frames_v2(xen_pfn_t *frames, unsigned int nr_gframes) |
1185 | { | |
1186 | uint64_t *sframes; | |
1187 | unsigned int nr_sframes; | |
1188 | struct gnttab_get_status_frames getframes; | |
1189 | int rc; | |
1190 | ||
1191 | nr_sframes = nr_status_frames(nr_gframes); | |
1192 | ||
1193 | /* No need for kzalloc as it is initialized in following hypercall | |
1194 | * GNTTABOP_get_status_frames. | |
1195 | */ | |
1196 | sframes = kmalloc_array(nr_sframes, sizeof(uint64_t), GFP_ATOMIC); | |
1197 | if (!sframes) | |
1198 | return -ENOMEM; | |
1199 | ||
1200 | getframes.dom = DOMID_SELF; | |
1201 | getframes.nr_frames = nr_sframes; | |
1202 | set_xen_guest_handle(getframes.frame_list, sframes); | |
1203 | ||
1204 | rc = HYPERVISOR_grant_table_op(GNTTABOP_get_status_frames, | |
1205 | &getframes, 1); | |
1206 | if (rc == -ENOSYS) { | |
1207 | kfree(sframes); | |
1208 | return -ENOSYS; | |
1209 | } | |
1210 | ||
1211 | BUG_ON(rc || getframes.status); | |
1212 | ||
1213 | rc = arch_gnttab_map_status(sframes, nr_sframes, | |
1214 | nr_status_frames(gnttab_max_grant_frames()), | |
1215 | &grstatus); | |
1216 | BUG_ON(rc); | |
1217 | kfree(sframes); | |
1218 | ||
1219 | rc = arch_gnttab_map_shared(frames, nr_gframes, | |
1220 | gnttab_max_grant_frames(), | |
1221 | &gnttab_shared.addr); | |
1222 | BUG_ON(rc); | |
1223 | ||
1224 | return 0; | |
1225 | } | |
1226 | ||
1227 | static void gnttab_unmap_frames_v2(void) | |
1228 | { | |
1229 | arch_gnttab_unmap(gnttab_shared.addr, nr_grant_frames); | |
1230 | arch_gnttab_unmap(grstatus, nr_status_frames(nr_grant_frames)); | |
1231 | } | |
1232 | ||
ad9a8612 JF |
1233 | static int gnttab_map(unsigned int start_idx, unsigned int end_idx) |
1234 | { | |
1235 | struct gnttab_setup_table setup; | |
ef32f892 | 1236 | xen_pfn_t *frames; |
ad9a8612 JF |
1237 | unsigned int nr_gframes = end_idx + 1; |
1238 | int rc; | |
1239 | ||
6926f6d6 | 1240 | if (xen_feature(XENFEAT_auto_translated_physmap)) { |
183d03cc SS |
1241 | struct xen_add_to_physmap xatp; |
1242 | unsigned int i = end_idx; | |
1243 | rc = 0; | |
efaf30a3 | 1244 | BUG_ON(xen_auto_xlat_grant_frames.count < nr_gframes); |
183d03cc SS |
1245 | /* |
1246 | * Loop backwards, so that the first hypercall has the largest | |
1247 | * index, ensuring that the table will grow only once. | |
1248 | */ | |
1249 | do { | |
1250 | xatp.domid = DOMID_SELF; | |
1251 | xatp.idx = i; | |
1252 | xatp.space = XENMAPSPACE_grant_table; | |
efaf30a3 | 1253 | xatp.gpfn = xen_auto_xlat_grant_frames.pfn[i]; |
183d03cc SS |
1254 | rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp); |
1255 | if (rc != 0) { | |
283c0972 JP |
1256 | pr_warn("grant table add_to_physmap failed, err=%d\n", |
1257 | rc); | |
183d03cc SS |
1258 | break; |
1259 | } | |
1260 | } while (i-- > start_idx); | |
1261 | ||
1262 | return rc; | |
1263 | } | |
1264 | ||
85ff6acb AL |
1265 | /* No need for kzalloc as it is initialized in following hypercall |
1266 | * GNTTABOP_setup_table. | |
1267 | */ | |
6da2ec56 | 1268 | frames = kmalloc_array(nr_gframes, sizeof(unsigned long), GFP_ATOMIC); |
ad9a8612 JF |
1269 | if (!frames) |
1270 | return -ENOMEM; | |
1271 | ||
1272 | setup.dom = DOMID_SELF; | |
1273 | setup.nr_frames = nr_gframes; | |
87e27cf6 | 1274 | set_xen_guest_handle(setup.frame_list, frames); |
ad9a8612 JF |
1275 | |
1276 | rc = HYPERVISOR_grant_table_op(GNTTABOP_setup_table, &setup, 1); | |
1277 | if (rc == -ENOSYS) { | |
1278 | kfree(frames); | |
1279 | return -ENOSYS; | |
1280 | } | |
1281 | ||
1282 | BUG_ON(rc || setup.status); | |
1283 | ||
0f9f5a95 | 1284 | rc = gnttab_interface->map_frames(frames, nr_gframes); |
ad9a8612 JF |
1285 | |
1286 | kfree(frames); | |
1287 | ||
0f9f5a95 AL |
1288 | return rc; |
1289 | } | |
1290 | ||
86fc2136 | 1291 | static const struct gnttab_ops gnttab_v1_ops = { |
83c69324 JG |
1292 | .version = 1, |
1293 | .grefs_per_grant_frame = XEN_PAGE_SIZE / | |
1294 | sizeof(struct grant_entry_v1), | |
0f9f5a95 AL |
1295 | .map_frames = gnttab_map_frames_v1, |
1296 | .unmap_frames = gnttab_unmap_frames_v1, | |
1297 | .update_entry = gnttab_update_entry_v1, | |
1298 | .end_foreign_access_ref = gnttab_end_foreign_access_ref_v1, | |
1299 | .end_foreign_transfer_ref = gnttab_end_foreign_transfer_ref_v1, | |
1300 | .query_foreign_access = gnttab_query_foreign_access_v1, | |
1301 | }; | |
1302 | ||
b988b8ff | 1303 | static const struct gnttab_ops gnttab_v2_ops = { |
83c69324 JG |
1304 | .version = 2, |
1305 | .grefs_per_grant_frame = XEN_PAGE_SIZE / | |
1306 | sizeof(union grant_entry_v2), | |
b988b8ff JG |
1307 | .map_frames = gnttab_map_frames_v2, |
1308 | .unmap_frames = gnttab_unmap_frames_v2, | |
1309 | .update_entry = gnttab_update_entry_v2, | |
1310 | .end_foreign_access_ref = gnttab_end_foreign_access_ref_v2, | |
1311 | .end_foreign_transfer_ref = gnttab_end_foreign_transfer_ref_v2, | |
1312 | .query_foreign_access = gnttab_query_foreign_access_v2, | |
b988b8ff JG |
1313 | }; |
1314 | ||
8dca4d96 | 1315 | static bool gnttab_need_v2(void) |
0f9f5a95 | 1316 | { |
8dca4d96 JG |
1317 | #ifdef CONFIG_X86 |
1318 | uint32_t base, width; | |
1319 | ||
1320 | if (xen_pv_domain()) { | |
1321 | base = xen_cpuid_base(); | |
1322 | if (cpuid_eax(base) < 5) | |
1323 | return false; /* Information not available, use V1. */ | |
1324 | width = cpuid_ebx(base + 5) & | |
1325 | XEN_CPUID_MACHINE_ADDRESS_WIDTH_MASK; | |
1326 | return width > 32 + PAGE_SHIFT; | |
1327 | } | |
1328 | #endif | |
1329 | return !!(max_possible_pfn >> 32); | |
1330 | } | |
85ff6acb | 1331 | |
0f9f5a95 AL |
1332 | static void gnttab_request_version(void) |
1333 | { | |
8dca4d96 | 1334 | long rc; |
b988b8ff | 1335 | struct gnttab_set_version gsv; |
85ff6acb | 1336 | |
8dca4d96 JG |
1337 | if (gnttab_need_v2()) |
1338 | gsv.version = 2; | |
1339 | else | |
1340 | gsv.version = 1; | |
1341 | ||
1342 | /* Boot parameter overrides automatic selection. */ | |
1343 | if (xen_gnttab_version >= 1 && xen_gnttab_version <= 2) | |
1344 | gsv.version = xen_gnttab_version; | |
b988b8ff JG |
1345 | |
1346 | rc = HYPERVISOR_grant_table_op(GNTTABOP_set_version, &gsv, 1); | |
83c69324 | 1347 | if (rc == 0 && gsv.version == 2) |
b988b8ff | 1348 | gnttab_interface = &gnttab_v2_ops; |
83c69324 | 1349 | else |
b988b8ff | 1350 | gnttab_interface = &gnttab_v1_ops; |
83c69324 JG |
1351 | pr_info("Grant tables using version %d layout\n", |
1352 | gnttab_interface->version); | |
ad9a8612 JF |
1353 | } |
1354 | ||
d0b4d64a | 1355 | static int gnttab_setup(void) |
ad9a8612 | 1356 | { |
183d03cc SS |
1357 | unsigned int max_nr_gframes; |
1358 | ||
1359 | max_nr_gframes = gnttab_max_grant_frames(); | |
1360 | if (max_nr_gframes < nr_grant_frames) | |
ad9a8612 | 1361 | return -ENOSYS; |
183d03cc | 1362 | |
45684753 | 1363 | if (xen_feature(XENFEAT_auto_translated_physmap) && gnttab_shared.addr == NULL) { |
efaf30a3 | 1364 | gnttab_shared.addr = xen_auto_xlat_grant_frames.vaddr; |
0f9f5a95 | 1365 | if (gnttab_shared.addr == NULL) { |
efaf30a3 KRW |
1366 | pr_warn("gnttab share frames (addr=0x%08lx) is not mapped!\n", |
1367 | (unsigned long)xen_auto_xlat_grant_frames.vaddr); | |
183d03cc SS |
1368 | return -ENOMEM; |
1369 | } | |
1370 | } | |
45684753 | 1371 | return gnttab_map(0, nr_grant_frames - 1); |
ad9a8612 JF |
1372 | } |
1373 | ||
d0b4d64a MW |
1374 | int gnttab_resume(void) |
1375 | { | |
1376 | gnttab_request_version(); | |
1377 | return gnttab_setup(); | |
1378 | } | |
1379 | ||
0e91398f | 1380 | int gnttab_suspend(void) |
ad9a8612 | 1381 | { |
13cd36a3 DV |
1382 | if (!xen_feature(XENFEAT_auto_translated_physmap)) |
1383 | gnttab_interface->unmap_frames(); | |
ad9a8612 JF |
1384 | return 0; |
1385 | } | |
1386 | ||
1387 | static int gnttab_expand(unsigned int req_entries) | |
1388 | { | |
1389 | int rc; | |
1390 | unsigned int cur, extra; | |
1391 | ||
83c69324 | 1392 | BUG_ON(gnttab_interface == NULL); |
ad9a8612 | 1393 | cur = nr_grant_frames; |
83c69324 JG |
1394 | extra = ((req_entries + gnttab_interface->grefs_per_grant_frame - 1) / |
1395 | gnttab_interface->grefs_per_grant_frame); | |
29d11cfd WW |
1396 | if (cur + extra > gnttab_max_grant_frames()) { |
1397 | pr_warn_ratelimited("xen/grant-table: max_grant_frames reached" | |
1398 | " cur=%u extra=%u limit=%u" | |
1399 | " gnttab_free_count=%u req_entries=%u\n", | |
1400 | cur, extra, gnttab_max_grant_frames(), | |
1401 | gnttab_free_count, req_entries); | |
ad9a8612 | 1402 | return -ENOSPC; |
29d11cfd | 1403 | } |
ad9a8612 JF |
1404 | |
1405 | rc = gnttab_map(cur, cur + extra - 1); | |
1406 | if (rc == 0) | |
1407 | rc = grow_gnttab_list(extra); | |
1408 | ||
1409 | return rc; | |
1410 | } | |
1411 | ||
183d03cc | 1412 | int gnttab_init(void) |
ad9a8612 JF |
1413 | { |
1414 | int i; | |
162e3717 | 1415 | unsigned long max_nr_grant_frames; |
bbc60c18 | 1416 | unsigned int max_nr_glist_frames, nr_glist_frames; |
ad9a8612 | 1417 | unsigned int nr_init_grefs; |
6b5e7d9e | 1418 | int ret; |
ad9a8612 | 1419 | |
d0b4d64a | 1420 | gnttab_request_version(); |
162e3717 | 1421 | max_nr_grant_frames = gnttab_max_grant_frames(); |
ad9a8612 | 1422 | nr_grant_frames = 1; |
ad9a8612 JF |
1423 | |
1424 | /* Determine the maximum number of frames required for the | |
1425 | * grant reference free list on the current hypervisor. | |
1426 | */ | |
83c69324 | 1427 | BUG_ON(gnttab_interface == NULL); |
162e3717 | 1428 | max_nr_glist_frames = (max_nr_grant_frames * |
83c69324 | 1429 | gnttab_interface->grefs_per_grant_frame / RPP); |
ad9a8612 | 1430 | |
6da2ec56 KC |
1431 | gnttab_list = kmalloc_array(max_nr_glist_frames, |
1432 | sizeof(grant_ref_t *), | |
1433 | GFP_KERNEL); | |
ad9a8612 JF |
1434 | if (gnttab_list == NULL) |
1435 | return -ENOMEM; | |
1436 | ||
83c69324 | 1437 | nr_glist_frames = gnttab_frames(nr_grant_frames, RPP); |
bbc60c18 | 1438 | for (i = 0; i < nr_glist_frames; i++) { |
ad9a8612 | 1439 | gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_KERNEL); |
6b5e7d9e JL |
1440 | if (gnttab_list[i] == NULL) { |
1441 | ret = -ENOMEM; | |
ad9a8612 | 1442 | goto ini_nomem; |
6b5e7d9e | 1443 | } |
ad9a8612 JF |
1444 | } |
1445 | ||
b988b8ff JG |
1446 | ret = arch_gnttab_init(max_nr_grant_frames, |
1447 | nr_status_frames(max_nr_grant_frames)); | |
162e3717 DV |
1448 | if (ret < 0) |
1449 | goto ini_nomem; | |
1450 | ||
d0b4d64a | 1451 | if (gnttab_setup() < 0) { |
6b5e7d9e JL |
1452 | ret = -ENODEV; |
1453 | goto ini_nomem; | |
1454 | } | |
ad9a8612 | 1455 | |
83c69324 JG |
1456 | nr_init_grefs = nr_grant_frames * |
1457 | gnttab_interface->grefs_per_grant_frame; | |
ad9a8612 JF |
1458 | |
1459 | for (i = NR_RESERVED_ENTRIES; i < nr_init_grefs - 1; i++) | |
1460 | gnttab_entry(i) = i + 1; | |
1461 | ||
1462 | gnttab_entry(nr_init_grefs - 1) = GNTTAB_LIST_END; | |
1463 | gnttab_free_count = nr_init_grefs - NR_RESERVED_ENTRIES; | |
1464 | gnttab_free_head = NR_RESERVED_ENTRIES; | |
1465 | ||
1466 | printk("Grant table initialized\n"); | |
1467 | return 0; | |
1468 | ||
1469 | ini_nomem: | |
1470 | for (i--; i >= 0; i--) | |
1471 | free_page((unsigned long)gnttab_list[i]); | |
1472 | kfree(gnttab_list); | |
6b5e7d9e | 1473 | return ret; |
ad9a8612 | 1474 | } |
183d03cc SS |
1475 | EXPORT_SYMBOL_GPL(gnttab_init); |
1476 | ||
345a5255 | 1477 | static int __gnttab_init(void) |
183d03cc | 1478 | { |
8613d78a BO |
1479 | if (!xen_domain()) |
1480 | return -ENODEV; | |
1481 | ||
183d03cc | 1482 | /* Delay grant-table initialization in the PV on HVM case */ |
8613d78a | 1483 | if (xen_hvm_domain() && !xen_pvh_domain()) |
183d03cc SS |
1484 | return 0; |
1485 | ||
183d03cc SS |
1486 | return gnttab_init(); |
1487 | } | |
6926f6d6 KRW |
1488 | /* Starts after core_initcall so that xen_pvh_gnttab_setup can be called |
1489 | * beforehand to initialize xen_auto_xlat_grant_frames. */ | |
1490 | core_initcall_sync(__gnttab_init); |