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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> |
ad9a8612 | 48 | |
1ccbf534 | 49 | #include <xen/xen.h> |
ad9a8612 JF |
50 | #include <xen/interface/xen.h> |
51 | #include <xen/page.h> | |
52 | #include <xen/grant_table.h> | |
183d03cc | 53 | #include <xen/interface/memory.h> |
85ff6acb | 54 | #include <xen/hvc-console.h> |
3d24bbd7 | 55 | #include <xen/swiotlb-xen.h> |
ff4b156f | 56 | #include <xen/balloon.h> |
8dca4d96 JG |
57 | #ifdef CONFIG_X86 |
58 | #include <asm/xen/cpuid.h> | |
59 | #endif | |
ecbf29cd | 60 | #include <asm/xen/hypercall.h> |
4d9310e3 | 61 | #include <asm/xen/interface.h> |
ad9a8612 JF |
62 | |
63 | #include <asm/pgtable.h> | |
64 | #include <asm/sync_bitops.h> | |
65 | ||
ad9a8612 JF |
66 | /* External tools reserve first few grant table entries. */ |
67 | #define NR_RESERVED_ENTRIES 8 | |
68 | #define GNTTAB_LIST_END 0xffffffff | |
ad9a8612 JF |
69 | |
70 | static grant_ref_t **gnttab_list; | |
71 | static unsigned int nr_grant_frames; | |
ad9a8612 JF |
72 | static int gnttab_free_count; |
73 | static grant_ref_t gnttab_free_head; | |
74 | static DEFINE_SPINLOCK(gnttab_list_lock); | |
efaf30a3 | 75 | struct grant_frames xen_auto_xlat_grant_frames; |
8dca4d96 JG |
76 | static unsigned int xen_gnttab_version; |
77 | module_param_named(version, xen_gnttab_version, uint, 0); | |
ad9a8612 | 78 | |
0f9f5a95 AL |
79 | static union { |
80 | struct grant_entry_v1 *v1; | |
b988b8ff | 81 | union grant_entry_v2 *v2; |
0f9f5a95 AL |
82 | void *addr; |
83 | } gnttab_shared; | |
84 | ||
85 | /*This is a structure of function pointers for grant table*/ | |
86 | struct gnttab_ops { | |
83c69324 JG |
87 | /* |
88 | * Version of the grant interface. | |
89 | */ | |
90 | unsigned int version; | |
91 | /* | |
92 | * Grant refs per grant frame. | |
93 | */ | |
94 | unsigned int grefs_per_grant_frame; | |
0f9f5a95 | 95 | /* |
9dbc71d5 AL |
96 | * Mapping a list of frames for storing grant entries. Frames parameter |
97 | * is used to store grant table address when grant table being setup, | |
98 | * nr_gframes is the number of frames to map grant table. Returning | |
99 | * GNTST_okay means success and negative value means failure. | |
0f9f5a95 | 100 | */ |
ef32f892 | 101 | int (*map_frames)(xen_pfn_t *frames, unsigned int nr_gframes); |
0f9f5a95 AL |
102 | /* |
103 | * Release a list of frames which are mapped in map_frames for grant | |
104 | * entry status. | |
105 | */ | |
106 | void (*unmap_frames)(void); | |
107 | /* | |
9dbc71d5 AL |
108 | * Introducing a valid entry into the grant table, granting the frame of |
109 | * this grant entry to domain for accessing or transfering. Ref | |
110 | * parameter is reference of this introduced grant entry, domid is id of | |
111 | * granted domain, frame is the page frame to be granted, and flags is | |
112 | * status of the grant entry to be updated. | |
0f9f5a95 | 113 | */ |
9dbc71d5 AL |
114 | void (*update_entry)(grant_ref_t ref, domid_t domid, |
115 | unsigned long frame, unsigned flags); | |
0f9f5a95 | 116 | /* |
9dbc71d5 AL |
117 | * Stop granting a grant entry to domain for accessing. Ref parameter is |
118 | * reference of a grant entry whose grant access will be stopped, | |
119 | * readonly is not in use in this function. If the grant entry is | |
0f9f5a95 AL |
120 | * currently mapped for reading or writing, just return failure(==0) |
121 | * directly and don't tear down the grant access. Otherwise, stop grant | |
122 | * access for this entry and return success(==1). | |
123 | */ | |
9dbc71d5 | 124 | int (*end_foreign_access_ref)(grant_ref_t ref, int readonly); |
0f9f5a95 | 125 | /* |
9dbc71d5 AL |
126 | * Stop granting a grant entry to domain for transfer. Ref parameter is |
127 | * reference of a grant entry whose grant transfer will be stopped. If | |
128 | * tranfer has not started, just reclaim the grant entry and return | |
129 | * failure(==0). Otherwise, wait for the transfer to complete and then | |
130 | * return the frame. | |
0f9f5a95 | 131 | */ |
9dbc71d5 | 132 | unsigned long (*end_foreign_transfer_ref)(grant_ref_t ref); |
0f9f5a95 | 133 | /* |
9dbc71d5 | 134 | * Query the status of a grant entry. Ref parameter is reference of |
0f9f5a95 AL |
135 | * queried grant entry, return value is the status of queried entry. |
136 | * Detailed status(writing/reading) can be gotten from the return value | |
137 | * by bit operations. | |
138 | */ | |
9dbc71d5 | 139 | int (*query_foreign_access)(grant_ref_t ref); |
0f9f5a95 AL |
140 | }; |
141 | ||
b44166cd BL |
142 | struct unmap_refs_callback_data { |
143 | struct completion completion; | |
144 | int result; | |
145 | }; | |
146 | ||
86fc2136 | 147 | static const struct gnttab_ops *gnttab_interface; |
0f9f5a95 | 148 | |
b988b8ff JG |
149 | /* This reflects status of grant entries, so act as a global value. */ |
150 | static grant_status_t *grstatus; | |
ad9a8612 JF |
151 | |
152 | static struct gnttab_free_callback *gnttab_free_callback_list; | |
153 | ||
154 | static int gnttab_expand(unsigned int req_entries); | |
155 | ||
156 | #define RPP (PAGE_SIZE / sizeof(grant_ref_t)) | |
b988b8ff | 157 | #define SPP (PAGE_SIZE / sizeof(grant_status_t)) |
ad9a8612 JF |
158 | |
159 | static inline grant_ref_t *__gnttab_entry(grant_ref_t entry) | |
160 | { | |
161 | return &gnttab_list[(entry) / RPP][(entry) % RPP]; | |
162 | } | |
163 | /* This can be used as an l-value */ | |
164 | #define gnttab_entry(entry) (*__gnttab_entry(entry)) | |
165 | ||
166 | static int get_free_entries(unsigned count) | |
167 | { | |
168 | unsigned long flags; | |
272800dc | 169 | int ref, rc = 0; |
ad9a8612 JF |
170 | grant_ref_t head; |
171 | ||
172 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
173 | ||
174 | if ((gnttab_free_count < count) && | |
175 | ((rc = gnttab_expand(count - gnttab_free_count)) < 0)) { | |
176 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
177 | return rc; | |
178 | } | |
179 | ||
180 | ref = head = gnttab_free_head; | |
181 | gnttab_free_count -= count; | |
182 | while (count-- > 1) | |
183 | head = gnttab_entry(head); | |
184 | gnttab_free_head = gnttab_entry(head); | |
185 | gnttab_entry(head) = GNTTAB_LIST_END; | |
186 | ||
187 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
188 | ||
189 | return ref; | |
190 | } | |
191 | ||
192 | static void do_free_callbacks(void) | |
193 | { | |
194 | struct gnttab_free_callback *callback, *next; | |
195 | ||
196 | callback = gnttab_free_callback_list; | |
197 | gnttab_free_callback_list = NULL; | |
198 | ||
199 | while (callback != NULL) { | |
200 | next = callback->next; | |
201 | if (gnttab_free_count >= callback->count) { | |
202 | callback->next = NULL; | |
203 | callback->fn(callback->arg); | |
204 | } else { | |
205 | callback->next = gnttab_free_callback_list; | |
206 | gnttab_free_callback_list = callback; | |
207 | } | |
208 | callback = next; | |
209 | } | |
210 | } | |
211 | ||
212 | static inline void check_free_callbacks(void) | |
213 | { | |
214 | if (unlikely(gnttab_free_callback_list)) | |
215 | do_free_callbacks(); | |
216 | } | |
217 | ||
218 | static void put_free_entry(grant_ref_t ref) | |
219 | { | |
220 | unsigned long flags; | |
221 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
222 | gnttab_entry(ref) = gnttab_free_head; | |
223 | gnttab_free_head = ref; | |
224 | gnttab_free_count++; | |
225 | check_free_callbacks(); | |
226 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
227 | } | |
228 | ||
0f9f5a95 | 229 | /* |
b988b8ff | 230 | * Following applies to gnttab_update_entry_v1 and gnttab_update_entry_v2. |
0f9f5a95 AL |
231 | * Introducing a valid entry into the grant table: |
232 | * 1. Write ent->domid. | |
233 | * 2. Write ent->frame: | |
234 | * GTF_permit_access: Frame to which access is permitted. | |
235 | * GTF_accept_transfer: Pseudo-phys frame slot being filled by new | |
236 | * frame, or zero if none. | |
237 | * 3. Write memory barrier (WMB). | |
238 | * 4. Write ent->flags, inc. valid type. | |
239 | */ | |
240 | static void gnttab_update_entry_v1(grant_ref_t ref, domid_t domid, | |
241 | unsigned long frame, unsigned flags) | |
ad9a8612 | 242 | { |
0f9f5a95 AL |
243 | gnttab_shared.v1[ref].domid = domid; |
244 | gnttab_shared.v1[ref].frame = frame; | |
ad9a8612 | 245 | wmb(); |
0f9f5a95 | 246 | gnttab_shared.v1[ref].flags = flags; |
ad9a8612 JF |
247 | } |
248 | ||
b988b8ff JG |
249 | static void gnttab_update_entry_v2(grant_ref_t ref, domid_t domid, |
250 | unsigned long frame, unsigned int flags) | |
251 | { | |
252 | gnttab_shared.v2[ref].hdr.domid = domid; | |
253 | gnttab_shared.v2[ref].full_page.frame = frame; | |
254 | wmb(); /* Hypervisor concurrent accesses. */ | |
255 | gnttab_shared.v2[ref].hdr.flags = GTF_permit_access | flags; | |
256 | } | |
257 | ||
ad9a8612 JF |
258 | /* |
259 | * Public grant-issuing interface functions | |
260 | */ | |
261 | void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid, | |
262 | unsigned long frame, int readonly) | |
263 | { | |
0f9f5a95 | 264 | gnttab_interface->update_entry(ref, domid, frame, |
ad9a8612 JF |
265 | GTF_permit_access | (readonly ? GTF_readonly : 0)); |
266 | } | |
267 | EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_ref); | |
268 | ||
269 | int gnttab_grant_foreign_access(domid_t domid, unsigned long frame, | |
270 | int readonly) | |
271 | { | |
272 | int ref; | |
273 | ||
274 | ref = get_free_entries(1); | |
275 | if (unlikely(ref < 0)) | |
276 | return -ENOSPC; | |
277 | ||
278 | gnttab_grant_foreign_access_ref(ref, domid, frame, readonly); | |
279 | ||
280 | return ref; | |
281 | } | |
282 | EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access); | |
283 | ||
0f9f5a95 | 284 | static int gnttab_query_foreign_access_v1(grant_ref_t ref) |
ad9a8612 | 285 | { |
0f9f5a95 AL |
286 | return gnttab_shared.v1[ref].flags & (GTF_reading|GTF_writing); |
287 | } | |
ad9a8612 | 288 | |
b988b8ff JG |
289 | static int gnttab_query_foreign_access_v2(grant_ref_t ref) |
290 | { | |
291 | return grstatus[ref] & (GTF_reading|GTF_writing); | |
292 | } | |
293 | ||
0f9f5a95 AL |
294 | int gnttab_query_foreign_access(grant_ref_t ref) |
295 | { | |
296 | return gnttab_interface->query_foreign_access(ref); | |
ad9a8612 JF |
297 | } |
298 | EXPORT_SYMBOL_GPL(gnttab_query_foreign_access); | |
299 | ||
0f9f5a95 | 300 | static int gnttab_end_foreign_access_ref_v1(grant_ref_t ref, int readonly) |
ad9a8612 JF |
301 | { |
302 | u16 flags, nflags; | |
b1e495b2 | 303 | u16 *pflags; |
ad9a8612 | 304 | |
b1e495b2 AL |
305 | pflags = &gnttab_shared.v1[ref].flags; |
306 | nflags = *pflags; | |
ad9a8612 JF |
307 | do { |
308 | flags = nflags; | |
569ca5b3 | 309 | if (flags & (GTF_reading|GTF_writing)) |
ad9a8612 | 310 | return 0; |
b1e495b2 | 311 | } while ((nflags = sync_cmpxchg(pflags, flags, 0)) != flags); |
ad9a8612 JF |
312 | |
313 | return 1; | |
314 | } | |
0f9f5a95 | 315 | |
b988b8ff JG |
316 | static int gnttab_end_foreign_access_ref_v2(grant_ref_t ref, int readonly) |
317 | { | |
318 | gnttab_shared.v2[ref].hdr.flags = 0; | |
319 | mb(); /* Concurrent access by hypervisor. */ | |
320 | if (grstatus[ref] & (GTF_reading|GTF_writing)) { | |
321 | return 0; | |
322 | } else { | |
323 | /* | |
324 | * The read of grstatus needs to have acquire semantics. | |
325 | * On x86, reads already have that, and we just need to | |
326 | * protect against compiler reorderings. | |
327 | * On other architectures we may need a full barrier. | |
328 | */ | |
329 | #ifdef CONFIG_X86 | |
330 | barrier(); | |
331 | #else | |
332 | mb(); | |
333 | #endif | |
334 | } | |
335 | ||
336 | return 1; | |
337 | } | |
338 | ||
569ca5b3 | 339 | static inline int _gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly) |
0f9f5a95 AL |
340 | { |
341 | return gnttab_interface->end_foreign_access_ref(ref, readonly); | |
342 | } | |
569ca5b3 JB |
343 | |
344 | int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly) | |
345 | { | |
346 | if (_gnttab_end_foreign_access_ref(ref, readonly)) | |
347 | return 1; | |
348 | pr_warn("WARNING: g.e. %#x still in use!\n", ref); | |
349 | return 0; | |
350 | } | |
ad9a8612 JF |
351 | EXPORT_SYMBOL_GPL(gnttab_end_foreign_access_ref); |
352 | ||
569ca5b3 JB |
353 | struct deferred_entry { |
354 | struct list_head list; | |
355 | grant_ref_t ref; | |
356 | bool ro; | |
357 | uint16_t warn_delay; | |
358 | struct page *page; | |
359 | }; | |
360 | static LIST_HEAD(deferred_list); | |
24ed960a | 361 | static void gnttab_handle_deferred(struct timer_list *); |
1d27e3e2 | 362 | static DEFINE_TIMER(deferred_timer, gnttab_handle_deferred); |
569ca5b3 | 363 | |
24ed960a | 364 | static void gnttab_handle_deferred(struct timer_list *unused) |
569ca5b3 JB |
365 | { |
366 | unsigned int nr = 10; | |
367 | struct deferred_entry *first = NULL; | |
368 | unsigned long flags; | |
369 | ||
370 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
371 | while (nr--) { | |
372 | struct deferred_entry *entry | |
373 | = list_first_entry(&deferred_list, | |
374 | struct deferred_entry, list); | |
375 | ||
376 | if (entry == first) | |
377 | break; | |
378 | list_del(&entry->list); | |
379 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
380 | if (_gnttab_end_foreign_access_ref(entry->ref, entry->ro)) { | |
381 | put_free_entry(entry->ref); | |
382 | if (entry->page) { | |
383 | pr_debug("freeing g.e. %#x (pfn %#lx)\n", | |
384 | entry->ref, page_to_pfn(entry->page)); | |
3ac7292a | 385 | put_page(entry->page); |
569ca5b3 JB |
386 | } else |
387 | pr_info("freeing g.e. %#x\n", entry->ref); | |
388 | kfree(entry); | |
389 | entry = NULL; | |
390 | } else { | |
391 | if (!--entry->warn_delay) | |
283c0972 | 392 | pr_info("g.e. %#x still pending\n", entry->ref); |
569ca5b3 JB |
393 | if (!first) |
394 | first = entry; | |
395 | } | |
396 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
397 | if (entry) | |
398 | list_add_tail(&entry->list, &deferred_list); | |
399 | else if (list_empty(&deferred_list)) | |
400 | break; | |
401 | } | |
402 | if (!list_empty(&deferred_list) && !timer_pending(&deferred_timer)) { | |
403 | deferred_timer.expires = jiffies + HZ; | |
404 | add_timer(&deferred_timer); | |
405 | } | |
406 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
407 | } | |
408 | ||
409 | static void gnttab_add_deferred(grant_ref_t ref, bool readonly, | |
410 | struct page *page) | |
411 | { | |
412 | struct deferred_entry *entry = kmalloc(sizeof(*entry), GFP_ATOMIC); | |
413 | const char *what = KERN_WARNING "leaking"; | |
414 | ||
415 | if (entry) { | |
416 | unsigned long flags; | |
417 | ||
418 | entry->ref = ref; | |
419 | entry->ro = readonly; | |
420 | entry->page = page; | |
421 | entry->warn_delay = 60; | |
422 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
423 | list_add_tail(&entry->list, &deferred_list); | |
424 | if (!timer_pending(&deferred_timer)) { | |
425 | deferred_timer.expires = jiffies + HZ; | |
426 | add_timer(&deferred_timer); | |
427 | } | |
428 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
429 | what = KERN_DEBUG "deferring"; | |
430 | } | |
431 | printk("%s g.e. %#x (pfn %#lx)\n", | |
432 | what, ref, page ? page_to_pfn(page) : -1); | |
433 | } | |
434 | ||
ad9a8612 JF |
435 | void gnttab_end_foreign_access(grant_ref_t ref, int readonly, |
436 | unsigned long page) | |
437 | { | |
438 | if (gnttab_end_foreign_access_ref(ref, readonly)) { | |
439 | put_free_entry(ref); | |
440 | if (page != 0) | |
3ac7292a | 441 | put_page(virt_to_page(page)); |
569ca5b3 JB |
442 | } else |
443 | gnttab_add_deferred(ref, readonly, | |
444 | page ? virt_to_page(page) : NULL); | |
ad9a8612 JF |
445 | } |
446 | EXPORT_SYMBOL_GPL(gnttab_end_foreign_access); | |
447 | ||
448 | int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn) | |
449 | { | |
450 | int ref; | |
451 | ||
452 | ref = get_free_entries(1); | |
453 | if (unlikely(ref < 0)) | |
454 | return -ENOSPC; | |
455 | gnttab_grant_foreign_transfer_ref(ref, domid, pfn); | |
456 | ||
457 | return ref; | |
458 | } | |
459 | EXPORT_SYMBOL_GPL(gnttab_grant_foreign_transfer); | |
460 | ||
461 | void gnttab_grant_foreign_transfer_ref(grant_ref_t ref, domid_t domid, | |
462 | unsigned long pfn) | |
463 | { | |
0f9f5a95 | 464 | gnttab_interface->update_entry(ref, domid, pfn, GTF_accept_transfer); |
ad9a8612 JF |
465 | } |
466 | EXPORT_SYMBOL_GPL(gnttab_grant_foreign_transfer_ref); | |
467 | ||
0f9f5a95 | 468 | static unsigned long gnttab_end_foreign_transfer_ref_v1(grant_ref_t ref) |
ad9a8612 JF |
469 | { |
470 | unsigned long frame; | |
471 | u16 flags; | |
b1e495b2 AL |
472 | u16 *pflags; |
473 | ||
474 | pflags = &gnttab_shared.v1[ref].flags; | |
ad9a8612 JF |
475 | |
476 | /* | |
477 | * If a transfer is not even yet started, try to reclaim the grant | |
478 | * reference and return failure (== 0). | |
479 | */ | |
b1e495b2 AL |
480 | while (!((flags = *pflags) & GTF_transfer_committed)) { |
481 | if (sync_cmpxchg(pflags, flags, 0) == flags) | |
ad9a8612 JF |
482 | return 0; |
483 | cpu_relax(); | |
484 | } | |
485 | ||
486 | /* If a transfer is in progress then wait until it is completed. */ | |
487 | while (!(flags & GTF_transfer_completed)) { | |
b1e495b2 | 488 | flags = *pflags; |
ad9a8612 JF |
489 | cpu_relax(); |
490 | } | |
491 | ||
492 | rmb(); /* Read the frame number /after/ reading completion status. */ | |
0f9f5a95 | 493 | frame = gnttab_shared.v1[ref].frame; |
ad9a8612 JF |
494 | BUG_ON(frame == 0); |
495 | ||
496 | return frame; | |
497 | } | |
0f9f5a95 | 498 | |
b988b8ff JG |
499 | static unsigned long gnttab_end_foreign_transfer_ref_v2(grant_ref_t ref) |
500 | { | |
501 | unsigned long frame; | |
502 | u16 flags; | |
503 | u16 *pflags; | |
504 | ||
505 | pflags = &gnttab_shared.v2[ref].hdr.flags; | |
506 | ||
507 | /* | |
508 | * If a transfer is not even yet started, try to reclaim the grant | |
509 | * reference and return failure (== 0). | |
510 | */ | |
511 | while (!((flags = *pflags) & GTF_transfer_committed)) { | |
512 | if (sync_cmpxchg(pflags, flags, 0) == flags) | |
513 | return 0; | |
514 | cpu_relax(); | |
515 | } | |
516 | ||
517 | /* If a transfer is in progress then wait until it is completed. */ | |
518 | while (!(flags & GTF_transfer_completed)) { | |
519 | flags = *pflags; | |
520 | cpu_relax(); | |
521 | } | |
522 | ||
523 | rmb(); /* Read the frame number /after/ reading completion status. */ | |
524 | frame = gnttab_shared.v2[ref].full_page.frame; | |
525 | BUG_ON(frame == 0); | |
526 | ||
527 | return frame; | |
528 | } | |
529 | ||
0f9f5a95 AL |
530 | unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref) |
531 | { | |
532 | return gnttab_interface->end_foreign_transfer_ref(ref); | |
533 | } | |
ad9a8612 JF |
534 | EXPORT_SYMBOL_GPL(gnttab_end_foreign_transfer_ref); |
535 | ||
536 | unsigned long gnttab_end_foreign_transfer(grant_ref_t ref) | |
537 | { | |
538 | unsigned long frame = gnttab_end_foreign_transfer_ref(ref); | |
539 | put_free_entry(ref); | |
540 | return frame; | |
541 | } | |
542 | EXPORT_SYMBOL_GPL(gnttab_end_foreign_transfer); | |
543 | ||
544 | void gnttab_free_grant_reference(grant_ref_t ref) | |
545 | { | |
546 | put_free_entry(ref); | |
547 | } | |
548 | EXPORT_SYMBOL_GPL(gnttab_free_grant_reference); | |
549 | ||
550 | void gnttab_free_grant_references(grant_ref_t head) | |
551 | { | |
552 | grant_ref_t ref; | |
553 | unsigned long flags; | |
554 | int count = 1; | |
555 | if (head == GNTTAB_LIST_END) | |
556 | return; | |
557 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
558 | ref = head; | |
559 | while (gnttab_entry(ref) != GNTTAB_LIST_END) { | |
560 | ref = gnttab_entry(ref); | |
561 | count++; | |
562 | } | |
563 | gnttab_entry(ref) = gnttab_free_head; | |
564 | gnttab_free_head = head; | |
565 | gnttab_free_count += count; | |
566 | check_free_callbacks(); | |
567 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
568 | } | |
569 | EXPORT_SYMBOL_GPL(gnttab_free_grant_references); | |
570 | ||
571 | int gnttab_alloc_grant_references(u16 count, grant_ref_t *head) | |
572 | { | |
573 | int h = get_free_entries(count); | |
574 | ||
575 | if (h < 0) | |
576 | return -ENOSPC; | |
577 | ||
578 | *head = h; | |
579 | ||
580 | return 0; | |
581 | } | |
582 | EXPORT_SYMBOL_GPL(gnttab_alloc_grant_references); | |
583 | ||
584 | int gnttab_empty_grant_references(const grant_ref_t *private_head) | |
585 | { | |
586 | return (*private_head == GNTTAB_LIST_END); | |
587 | } | |
588 | EXPORT_SYMBOL_GPL(gnttab_empty_grant_references); | |
589 | ||
590 | int gnttab_claim_grant_reference(grant_ref_t *private_head) | |
591 | { | |
592 | grant_ref_t g = *private_head; | |
593 | if (unlikely(g == GNTTAB_LIST_END)) | |
594 | return -ENOSPC; | |
595 | *private_head = gnttab_entry(g); | |
596 | return g; | |
597 | } | |
598 | EXPORT_SYMBOL_GPL(gnttab_claim_grant_reference); | |
599 | ||
600 | void gnttab_release_grant_reference(grant_ref_t *private_head, | |
601 | grant_ref_t release) | |
602 | { | |
603 | gnttab_entry(release) = *private_head; | |
604 | *private_head = release; | |
605 | } | |
606 | EXPORT_SYMBOL_GPL(gnttab_release_grant_reference); | |
607 | ||
608 | void gnttab_request_free_callback(struct gnttab_free_callback *callback, | |
609 | void (*fn)(void *), void *arg, u16 count) | |
610 | { | |
611 | unsigned long flags; | |
5f338d90 RPM |
612 | struct gnttab_free_callback *cb; |
613 | ||
ad9a8612 | 614 | spin_lock_irqsave(&gnttab_list_lock, flags); |
5f338d90 RPM |
615 | |
616 | /* Check if the callback is already on the list */ | |
617 | cb = gnttab_free_callback_list; | |
618 | while (cb) { | |
619 | if (cb == callback) | |
620 | goto out; | |
621 | cb = cb->next; | |
622 | } | |
623 | ||
ad9a8612 JF |
624 | callback->fn = fn; |
625 | callback->arg = arg; | |
626 | callback->count = count; | |
627 | callback->next = gnttab_free_callback_list; | |
628 | gnttab_free_callback_list = callback; | |
629 | check_free_callbacks(); | |
630 | out: | |
631 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
632 | } | |
633 | EXPORT_SYMBOL_GPL(gnttab_request_free_callback); | |
634 | ||
635 | void gnttab_cancel_free_callback(struct gnttab_free_callback *callback) | |
636 | { | |
637 | struct gnttab_free_callback **pcb; | |
638 | unsigned long flags; | |
639 | ||
640 | spin_lock_irqsave(&gnttab_list_lock, flags); | |
641 | for (pcb = &gnttab_free_callback_list; *pcb; pcb = &(*pcb)->next) { | |
642 | if (*pcb == callback) { | |
643 | *pcb = callback->next; | |
644 | break; | |
645 | } | |
646 | } | |
647 | spin_unlock_irqrestore(&gnttab_list_lock, flags); | |
648 | } | |
649 | EXPORT_SYMBOL_GPL(gnttab_cancel_free_callback); | |
650 | ||
83c69324 JG |
651 | static unsigned int gnttab_frames(unsigned int frames, unsigned int align) |
652 | { | |
653 | return (frames * gnttab_interface->grefs_per_grant_frame + align - 1) / | |
654 | align; | |
655 | } | |
656 | ||
ad9a8612 JF |
657 | static int grow_gnttab_list(unsigned int more_frames) |
658 | { | |
659 | unsigned int new_nr_grant_frames, extra_entries, i; | |
bbc60c18 | 660 | unsigned int nr_glist_frames, new_nr_glist_frames; |
83c69324 | 661 | unsigned int grefs_per_frame; |
ad9a8612 | 662 | |
83c69324 JG |
663 | BUG_ON(gnttab_interface == NULL); |
664 | grefs_per_frame = gnttab_interface->grefs_per_grant_frame; | |
d0b4d64a | 665 | |
ad9a8612 | 666 | new_nr_grant_frames = nr_grant_frames + more_frames; |
83c69324 | 667 | extra_entries = more_frames * grefs_per_frame; |
ad9a8612 | 668 | |
83c69324 JG |
669 | nr_glist_frames = gnttab_frames(nr_grant_frames, RPP); |
670 | new_nr_glist_frames = gnttab_frames(new_nr_grant_frames, RPP); | |
bbc60c18 | 671 | for (i = nr_glist_frames; i < new_nr_glist_frames; i++) { |
ad9a8612 JF |
672 | gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_ATOMIC); |
673 | if (!gnttab_list[i]) | |
674 | goto grow_nomem; | |
675 | } | |
676 | ||
677 | ||
83c69324 JG |
678 | for (i = grefs_per_frame * nr_grant_frames; |
679 | i < grefs_per_frame * new_nr_grant_frames - 1; i++) | |
ad9a8612 JF |
680 | gnttab_entry(i) = i + 1; |
681 | ||
682 | gnttab_entry(i) = gnttab_free_head; | |
83c69324 | 683 | gnttab_free_head = grefs_per_frame * nr_grant_frames; |
ad9a8612 JF |
684 | gnttab_free_count += extra_entries; |
685 | ||
686 | nr_grant_frames = new_nr_grant_frames; | |
687 | ||
688 | check_free_callbacks(); | |
689 | ||
690 | return 0; | |
691 | ||
692 | grow_nomem: | |
46e3626a | 693 | while (i-- > nr_glist_frames) |
ad9a8612 JF |
694 | free_page((unsigned long) gnttab_list[i]); |
695 | return -ENOMEM; | |
696 | } | |
697 | ||
698 | static unsigned int __max_nr_grant_frames(void) | |
699 | { | |
700 | struct gnttab_query_size query; | |
701 | int rc; | |
702 | ||
703 | query.dom = DOMID_SELF; | |
704 | ||
705 | rc = HYPERVISOR_grant_table_op(GNTTABOP_query_size, &query, 1); | |
706 | if ((rc < 0) || (query.status != GNTST_okay)) | |
707 | return 4; /* Legacy max supported number of frames */ | |
708 | ||
709 | return query.max_nr_frames; | |
710 | } | |
711 | ||
183d03cc | 712 | unsigned int gnttab_max_grant_frames(void) |
ad9a8612 JF |
713 | { |
714 | unsigned int xen_max = __max_nr_grant_frames(); | |
7f256020 KRW |
715 | static unsigned int boot_max_nr_grant_frames; |
716 | ||
717 | /* First time, initialize it properly. */ | |
718 | if (!boot_max_nr_grant_frames) | |
719 | boot_max_nr_grant_frames = __max_nr_grant_frames(); | |
ad9a8612 JF |
720 | |
721 | if (xen_max > boot_max_nr_grant_frames) | |
722 | return boot_max_nr_grant_frames; | |
723 | return xen_max; | |
724 | } | |
183d03cc | 725 | EXPORT_SYMBOL_GPL(gnttab_max_grant_frames); |
ad9a8612 | 726 | |
47c54205 | 727 | int gnttab_setup_auto_xlat_frames(phys_addr_t addr) |
efaf30a3 KRW |
728 | { |
729 | xen_pfn_t *pfn; | |
730 | unsigned int max_nr_gframes = __max_nr_grant_frames(); | |
731 | unsigned int i; | |
732 | void *vaddr; | |
733 | ||
734 | if (xen_auto_xlat_grant_frames.count) | |
735 | return -EINVAL; | |
736 | ||
5ed5451d | 737 | vaddr = xen_remap(addr, XEN_PAGE_SIZE * max_nr_gframes); |
efaf30a3 | 738 | if (vaddr == NULL) { |
47c54205 JG |
739 | pr_warn("Failed to ioremap gnttab share frames (addr=%pa)!\n", |
740 | &addr); | |
efaf30a3 KRW |
741 | return -ENOMEM; |
742 | } | |
743 | pfn = kcalloc(max_nr_gframes, sizeof(pfn[0]), GFP_KERNEL); | |
744 | if (!pfn) { | |
745 | xen_unmap(vaddr); | |
746 | return -ENOMEM; | |
747 | } | |
748 | for (i = 0; i < max_nr_gframes; i++) | |
5ed5451d | 749 | pfn[i] = XEN_PFN_DOWN(addr) + i; |
efaf30a3 KRW |
750 | |
751 | xen_auto_xlat_grant_frames.vaddr = vaddr; | |
752 | xen_auto_xlat_grant_frames.pfn = pfn; | |
753 | xen_auto_xlat_grant_frames.count = max_nr_gframes; | |
754 | ||
755 | return 0; | |
756 | } | |
757 | EXPORT_SYMBOL_GPL(gnttab_setup_auto_xlat_frames); | |
758 | ||
759 | void gnttab_free_auto_xlat_frames(void) | |
760 | { | |
761 | if (!xen_auto_xlat_grant_frames.count) | |
762 | return; | |
763 | kfree(xen_auto_xlat_grant_frames.pfn); | |
764 | xen_unmap(xen_auto_xlat_grant_frames.vaddr); | |
765 | ||
766 | xen_auto_xlat_grant_frames.pfn = NULL; | |
767 | xen_auto_xlat_grant_frames.count = 0; | |
768 | xen_auto_xlat_grant_frames.vaddr = NULL; | |
769 | } | |
770 | EXPORT_SYMBOL_GPL(gnttab_free_auto_xlat_frames); | |
771 | ||
ff4b156f DV |
772 | /** |
773 | * gnttab_alloc_pages - alloc pages suitable for grant mapping into | |
774 | * @nr_pages: number of pages to alloc | |
775 | * @pages: returns the pages | |
776 | */ | |
777 | int gnttab_alloc_pages(int nr_pages, struct page **pages) | |
778 | { | |
8da7633f | 779 | int i; |
ff4b156f DV |
780 | int ret; |
781 | ||
81b286e0 | 782 | ret = alloc_xenballooned_pages(nr_pages, pages); |
ff4b156f DV |
783 | if (ret < 0) |
784 | return ret; | |
785 | ||
8da7633f JH |
786 | for (i = 0; i < nr_pages; i++) { |
787 | #if BITS_PER_LONG < 64 | |
788 | struct xen_page_foreign *foreign; | |
789 | ||
790 | foreign = kzalloc(sizeof(*foreign), GFP_KERNEL); | |
791 | if (!foreign) { | |
792 | gnttab_free_pages(nr_pages, pages); | |
793 | return -ENOMEM; | |
794 | } | |
795 | set_page_private(pages[i], (unsigned long)foreign); | |
796 | #endif | |
797 | SetPagePrivate(pages[i]); | |
798 | } | |
799 | ||
ff4b156f DV |
800 | return 0; |
801 | } | |
802 | EXPORT_SYMBOL(gnttab_alloc_pages); | |
803 | ||
804 | /** | |
805 | * gnttab_free_pages - free pages allocated by gnttab_alloc_pages() | |
806 | * @nr_pages; number of pages to free | |
807 | * @pages: the pages | |
808 | */ | |
809 | void gnttab_free_pages(int nr_pages, struct page **pages) | |
810 | { | |
8da7633f JH |
811 | int i; |
812 | ||
813 | for (i = 0; i < nr_pages; i++) { | |
814 | if (PagePrivate(pages[i])) { | |
815 | #if BITS_PER_LONG < 64 | |
816 | kfree((void *)page_private(pages[i])); | |
817 | #endif | |
818 | ClearPagePrivate(pages[i]); | |
819 | } | |
820 | } | |
ff4b156f DV |
821 | free_xenballooned_pages(nr_pages, pages); |
822 | } | |
823 | EXPORT_SYMBOL(gnttab_free_pages); | |
824 | ||
c571898f ALC |
825 | /* Handling of paged out grant targets (GNTST_eagain) */ |
826 | #define MAX_DELAY 256 | |
827 | static inline void | |
828 | gnttab_retry_eagain_gop(unsigned int cmd, void *gop, int16_t *status, | |
829 | const char *func) | |
830 | { | |
831 | unsigned delay = 1; | |
832 | ||
833 | do { | |
834 | BUG_ON(HYPERVISOR_grant_table_op(cmd, gop, 1)); | |
835 | if (*status == GNTST_eagain) | |
836 | msleep(delay++); | |
837 | } while ((*status == GNTST_eagain) && (delay < MAX_DELAY)); | |
838 | ||
839 | if (delay >= MAX_DELAY) { | |
283c0972 | 840 | pr_err("%s: %s eagain grant\n", func, current->comm); |
c571898f ALC |
841 | *status = GNTST_bad_page; |
842 | } | |
843 | } | |
844 | ||
845 | void gnttab_batch_map(struct gnttab_map_grant_ref *batch, unsigned count) | |
846 | { | |
847 | struct gnttab_map_grant_ref *op; | |
848 | ||
849 | if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, batch, count)) | |
850 | BUG(); | |
851 | for (op = batch; op < batch + count; op++) | |
852 | if (op->status == GNTST_eagain) | |
853 | gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref, op, | |
854 | &op->status, __func__); | |
855 | } | |
856 | EXPORT_SYMBOL_GPL(gnttab_batch_map); | |
857 | ||
858 | void gnttab_batch_copy(struct gnttab_copy *batch, unsigned count) | |
859 | { | |
860 | struct gnttab_copy *op; | |
861 | ||
862 | if (HYPERVISOR_grant_table_op(GNTTABOP_copy, batch, count)) | |
863 | BUG(); | |
864 | for (op = batch; op < batch + count; op++) | |
865 | if (op->status == GNTST_eagain) | |
866 | gnttab_retry_eagain_gop(GNTTABOP_copy, op, | |
867 | &op->status, __func__); | |
868 | } | |
869 | EXPORT_SYMBOL_GPL(gnttab_batch_copy); | |
870 | ||
008c320a JG |
871 | void gnttab_foreach_grant_in_range(struct page *page, |
872 | unsigned int offset, | |
873 | unsigned int len, | |
874 | xen_grant_fn_t fn, | |
875 | void *data) | |
876 | { | |
877 | unsigned int goffset; | |
878 | unsigned int glen; | |
879 | unsigned long xen_pfn; | |
880 | ||
881 | len = min_t(unsigned int, PAGE_SIZE - offset, len); | |
882 | goffset = xen_offset_in_page(offset); | |
883 | ||
884 | xen_pfn = page_to_xen_pfn(page) + XEN_PFN_DOWN(offset); | |
885 | ||
886 | while (len) { | |
887 | glen = min_t(unsigned int, XEN_PAGE_SIZE - goffset, len); | |
888 | fn(pfn_to_gfn(xen_pfn), goffset, glen, data); | |
889 | ||
890 | goffset = 0; | |
891 | xen_pfn++; | |
892 | len -= glen; | |
893 | } | |
894 | } | |
895 | EXPORT_SYMBOL_GPL(gnttab_foreach_grant_in_range); | |
896 | ||
f73314b2 JG |
897 | void gnttab_foreach_grant(struct page **pages, |
898 | unsigned int nr_grefs, | |
899 | xen_grant_fn_t fn, | |
900 | void *data) | |
901 | { | |
902 | unsigned int goffset = 0; | |
903 | unsigned long xen_pfn = 0; | |
904 | unsigned int i; | |
905 | ||
906 | for (i = 0; i < nr_grefs; i++) { | |
907 | if ((i % XEN_PFN_PER_PAGE) == 0) { | |
908 | xen_pfn = page_to_xen_pfn(pages[i / XEN_PFN_PER_PAGE]); | |
909 | goffset = 0; | |
910 | } | |
911 | ||
912 | fn(pfn_to_gfn(xen_pfn), goffset, XEN_PAGE_SIZE, data); | |
913 | ||
914 | goffset += XEN_PAGE_SIZE; | |
915 | xen_pfn++; | |
916 | } | |
917 | } | |
918 | ||
e85fc980 | 919 | int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, |
c123799a | 920 | struct gnttab_map_grant_ref *kmap_ops, |
e85fc980 | 921 | struct page **pages, unsigned int count) |
289b777e SS |
922 | { |
923 | int i, ret; | |
289b777e SS |
924 | |
925 | ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, map_ops, count); | |
87f1d40a JF |
926 | if (ret) |
927 | return ret; | |
289b777e | 928 | |
8da7633f JH |
929 | for (i = 0; i < count; i++) { |
930 | /* Retry eagain maps */ | |
c571898f ALC |
931 | if (map_ops[i].status == GNTST_eagain) |
932 | gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref, map_ops + i, | |
933 | &map_ops[i].status, __func__); | |
934 | ||
8da7633f JH |
935 | if (map_ops[i].status == GNTST_okay) { |
936 | struct xen_page_foreign *foreign; | |
937 | ||
938 | SetPageForeign(pages[i]); | |
939 | foreign = xen_page_foreign(pages[i]); | |
940 | foreign->domid = map_ops[i].dom; | |
941 | foreign->gref = map_ops[i].ref; | |
942 | } | |
943 | } | |
944 | ||
1429d46d | 945 | return set_foreign_p2m_mapping(map_ops, kmap_ops, pages, count); |
289b777e SS |
946 | } |
947 | EXPORT_SYMBOL_GPL(gnttab_map_refs); | |
948 | ||
e85fc980 | 949 | int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops, |
853d0289 | 950 | struct gnttab_unmap_grant_ref *kunmap_ops, |
e85fc980 | 951 | struct page **pages, unsigned int count) |
289b777e | 952 | { |
8da7633f | 953 | unsigned int i; |
1429d46d | 954 | int ret; |
289b777e SS |
955 | |
956 | ret = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap_ops, count); | |
87f1d40a JF |
957 | if (ret) |
958 | return ret; | |
959 | ||
8da7633f JH |
960 | for (i = 0; i < count; i++) |
961 | ClearPageForeign(pages[i]); | |
962 | ||
853d0289 | 963 | return clear_foreign_p2m_mapping(unmap_ops, kunmap_ops, pages, count); |
289b777e SS |
964 | } |
965 | EXPORT_SYMBOL_GPL(gnttab_unmap_refs); | |
966 | ||
3f9f1c67 JH |
967 | #define GNTTAB_UNMAP_REFS_DELAY 5 |
968 | ||
969 | static void __gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item); | |
970 | ||
971 | static void gnttab_unmap_work(struct work_struct *work) | |
972 | { | |
973 | struct gntab_unmap_queue_data | |
974 | *unmap_data = container_of(work, | |
975 | struct gntab_unmap_queue_data, | |
976 | gnttab_work.work); | |
977 | if (unmap_data->age != UINT_MAX) | |
978 | unmap_data->age++; | |
979 | __gnttab_unmap_refs_async(unmap_data); | |
980 | } | |
981 | ||
982 | static void __gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item) | |
983 | { | |
984 | int ret; | |
985 | int pc; | |
986 | ||
987 | for (pc = 0; pc < item->count; pc++) { | |
988 | if (page_count(item->pages[pc]) > 1) { | |
989 | unsigned long delay = GNTTAB_UNMAP_REFS_DELAY * (item->age + 1); | |
990 | schedule_delayed_work(&item->gnttab_work, | |
991 | msecs_to_jiffies(delay)); | |
992 | return; | |
993 | } | |
994 | } | |
995 | ||
996 | ret = gnttab_unmap_refs(item->unmap_ops, item->kunmap_ops, | |
997 | item->pages, item->count); | |
998 | item->done(ret, item); | |
999 | } | |
1000 | ||
1001 | void gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item) | |
1002 | { | |
1003 | INIT_DELAYED_WORK(&item->gnttab_work, gnttab_unmap_work); | |
1004 | item->age = 0; | |
1005 | ||
1006 | __gnttab_unmap_refs_async(item); | |
1007 | } | |
1008 | EXPORT_SYMBOL_GPL(gnttab_unmap_refs_async); | |
1009 | ||
b44166cd BL |
1010 | static void unmap_refs_callback(int result, |
1011 | struct gntab_unmap_queue_data *data) | |
1012 | { | |
1013 | struct unmap_refs_callback_data *d = data->data; | |
1014 | ||
1015 | d->result = result; | |
1016 | complete(&d->completion); | |
1017 | } | |
1018 | ||
1019 | int gnttab_unmap_refs_sync(struct gntab_unmap_queue_data *item) | |
1020 | { | |
1021 | struct unmap_refs_callback_data data; | |
1022 | ||
1023 | init_completion(&data.completion); | |
1024 | item->data = &data; | |
1025 | item->done = &unmap_refs_callback; | |
1026 | gnttab_unmap_refs_async(item); | |
1027 | wait_for_completion(&data.completion); | |
1028 | ||
1029 | return data.result; | |
1030 | } | |
1031 | EXPORT_SYMBOL_GPL(gnttab_unmap_refs_sync); | |
1032 | ||
b988b8ff JG |
1033 | static unsigned int nr_status_frames(unsigned int nr_grant_frames) |
1034 | { | |
83c69324 JG |
1035 | BUG_ON(gnttab_interface == NULL); |
1036 | return gnttab_frames(nr_grant_frames, SPP); | |
b988b8ff JG |
1037 | } |
1038 | ||
ef32f892 | 1039 | static int gnttab_map_frames_v1(xen_pfn_t *frames, unsigned int nr_gframes) |
0f9f5a95 AL |
1040 | { |
1041 | int rc; | |
1042 | ||
1043 | rc = arch_gnttab_map_shared(frames, nr_gframes, | |
1044 | gnttab_max_grant_frames(), | |
1045 | &gnttab_shared.addr); | |
1046 | BUG_ON(rc); | |
1047 | ||
1048 | return 0; | |
1049 | } | |
1050 | ||
1051 | static void gnttab_unmap_frames_v1(void) | |
1052 | { | |
85ff6acb AL |
1053 | arch_gnttab_unmap(gnttab_shared.addr, nr_grant_frames); |
1054 | } | |
1055 | ||
b988b8ff JG |
1056 | static int gnttab_map_frames_v2(xen_pfn_t *frames, unsigned int nr_gframes) |
1057 | { | |
1058 | uint64_t *sframes; | |
1059 | unsigned int nr_sframes; | |
1060 | struct gnttab_get_status_frames getframes; | |
1061 | int rc; | |
1062 | ||
1063 | nr_sframes = nr_status_frames(nr_gframes); | |
1064 | ||
1065 | /* No need for kzalloc as it is initialized in following hypercall | |
1066 | * GNTTABOP_get_status_frames. | |
1067 | */ | |
1068 | sframes = kmalloc_array(nr_sframes, sizeof(uint64_t), GFP_ATOMIC); | |
1069 | if (!sframes) | |
1070 | return -ENOMEM; | |
1071 | ||
1072 | getframes.dom = DOMID_SELF; | |
1073 | getframes.nr_frames = nr_sframes; | |
1074 | set_xen_guest_handle(getframes.frame_list, sframes); | |
1075 | ||
1076 | rc = HYPERVISOR_grant_table_op(GNTTABOP_get_status_frames, | |
1077 | &getframes, 1); | |
1078 | if (rc == -ENOSYS) { | |
1079 | kfree(sframes); | |
1080 | return -ENOSYS; | |
1081 | } | |
1082 | ||
1083 | BUG_ON(rc || getframes.status); | |
1084 | ||
1085 | rc = arch_gnttab_map_status(sframes, nr_sframes, | |
1086 | nr_status_frames(gnttab_max_grant_frames()), | |
1087 | &grstatus); | |
1088 | BUG_ON(rc); | |
1089 | kfree(sframes); | |
1090 | ||
1091 | rc = arch_gnttab_map_shared(frames, nr_gframes, | |
1092 | gnttab_max_grant_frames(), | |
1093 | &gnttab_shared.addr); | |
1094 | BUG_ON(rc); | |
1095 | ||
1096 | return 0; | |
1097 | } | |
1098 | ||
1099 | static void gnttab_unmap_frames_v2(void) | |
1100 | { | |
1101 | arch_gnttab_unmap(gnttab_shared.addr, nr_grant_frames); | |
1102 | arch_gnttab_unmap(grstatus, nr_status_frames(nr_grant_frames)); | |
1103 | } | |
1104 | ||
ad9a8612 JF |
1105 | static int gnttab_map(unsigned int start_idx, unsigned int end_idx) |
1106 | { | |
1107 | struct gnttab_setup_table setup; | |
ef32f892 | 1108 | xen_pfn_t *frames; |
ad9a8612 JF |
1109 | unsigned int nr_gframes = end_idx + 1; |
1110 | int rc; | |
1111 | ||
6926f6d6 | 1112 | if (xen_feature(XENFEAT_auto_translated_physmap)) { |
183d03cc SS |
1113 | struct xen_add_to_physmap xatp; |
1114 | unsigned int i = end_idx; | |
1115 | rc = 0; | |
efaf30a3 | 1116 | BUG_ON(xen_auto_xlat_grant_frames.count < nr_gframes); |
183d03cc SS |
1117 | /* |
1118 | * Loop backwards, so that the first hypercall has the largest | |
1119 | * index, ensuring that the table will grow only once. | |
1120 | */ | |
1121 | do { | |
1122 | xatp.domid = DOMID_SELF; | |
1123 | xatp.idx = i; | |
1124 | xatp.space = XENMAPSPACE_grant_table; | |
efaf30a3 | 1125 | xatp.gpfn = xen_auto_xlat_grant_frames.pfn[i]; |
183d03cc SS |
1126 | rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp); |
1127 | if (rc != 0) { | |
283c0972 JP |
1128 | pr_warn("grant table add_to_physmap failed, err=%d\n", |
1129 | rc); | |
183d03cc SS |
1130 | break; |
1131 | } | |
1132 | } while (i-- > start_idx); | |
1133 | ||
1134 | return rc; | |
1135 | } | |
1136 | ||
85ff6acb AL |
1137 | /* No need for kzalloc as it is initialized in following hypercall |
1138 | * GNTTABOP_setup_table. | |
1139 | */ | |
ad9a8612 JF |
1140 | frames = kmalloc(nr_gframes * sizeof(unsigned long), GFP_ATOMIC); |
1141 | if (!frames) | |
1142 | return -ENOMEM; | |
1143 | ||
1144 | setup.dom = DOMID_SELF; | |
1145 | setup.nr_frames = nr_gframes; | |
87e27cf6 | 1146 | set_xen_guest_handle(setup.frame_list, frames); |
ad9a8612 JF |
1147 | |
1148 | rc = HYPERVISOR_grant_table_op(GNTTABOP_setup_table, &setup, 1); | |
1149 | if (rc == -ENOSYS) { | |
1150 | kfree(frames); | |
1151 | return -ENOSYS; | |
1152 | } | |
1153 | ||
1154 | BUG_ON(rc || setup.status); | |
1155 | ||
0f9f5a95 | 1156 | rc = gnttab_interface->map_frames(frames, nr_gframes); |
ad9a8612 JF |
1157 | |
1158 | kfree(frames); | |
1159 | ||
0f9f5a95 AL |
1160 | return rc; |
1161 | } | |
1162 | ||
86fc2136 | 1163 | static const struct gnttab_ops gnttab_v1_ops = { |
83c69324 JG |
1164 | .version = 1, |
1165 | .grefs_per_grant_frame = XEN_PAGE_SIZE / | |
1166 | sizeof(struct grant_entry_v1), | |
0f9f5a95 AL |
1167 | .map_frames = gnttab_map_frames_v1, |
1168 | .unmap_frames = gnttab_unmap_frames_v1, | |
1169 | .update_entry = gnttab_update_entry_v1, | |
1170 | .end_foreign_access_ref = gnttab_end_foreign_access_ref_v1, | |
1171 | .end_foreign_transfer_ref = gnttab_end_foreign_transfer_ref_v1, | |
1172 | .query_foreign_access = gnttab_query_foreign_access_v1, | |
1173 | }; | |
1174 | ||
b988b8ff | 1175 | static const struct gnttab_ops gnttab_v2_ops = { |
83c69324 JG |
1176 | .version = 2, |
1177 | .grefs_per_grant_frame = XEN_PAGE_SIZE / | |
1178 | sizeof(union grant_entry_v2), | |
b988b8ff JG |
1179 | .map_frames = gnttab_map_frames_v2, |
1180 | .unmap_frames = gnttab_unmap_frames_v2, | |
1181 | .update_entry = gnttab_update_entry_v2, | |
1182 | .end_foreign_access_ref = gnttab_end_foreign_access_ref_v2, | |
1183 | .end_foreign_transfer_ref = gnttab_end_foreign_transfer_ref_v2, | |
1184 | .query_foreign_access = gnttab_query_foreign_access_v2, | |
b988b8ff JG |
1185 | }; |
1186 | ||
8dca4d96 | 1187 | static bool gnttab_need_v2(void) |
0f9f5a95 | 1188 | { |
8dca4d96 JG |
1189 | #ifdef CONFIG_X86 |
1190 | uint32_t base, width; | |
1191 | ||
1192 | if (xen_pv_domain()) { | |
1193 | base = xen_cpuid_base(); | |
1194 | if (cpuid_eax(base) < 5) | |
1195 | return false; /* Information not available, use V1. */ | |
1196 | width = cpuid_ebx(base + 5) & | |
1197 | XEN_CPUID_MACHINE_ADDRESS_WIDTH_MASK; | |
1198 | return width > 32 + PAGE_SHIFT; | |
1199 | } | |
1200 | #endif | |
1201 | return !!(max_possible_pfn >> 32); | |
1202 | } | |
85ff6acb | 1203 | |
0f9f5a95 AL |
1204 | static void gnttab_request_version(void) |
1205 | { | |
8dca4d96 | 1206 | long rc; |
b988b8ff | 1207 | struct gnttab_set_version gsv; |
85ff6acb | 1208 | |
8dca4d96 JG |
1209 | if (gnttab_need_v2()) |
1210 | gsv.version = 2; | |
1211 | else | |
1212 | gsv.version = 1; | |
1213 | ||
1214 | /* Boot parameter overrides automatic selection. */ | |
1215 | if (xen_gnttab_version >= 1 && xen_gnttab_version <= 2) | |
1216 | gsv.version = xen_gnttab_version; | |
b988b8ff JG |
1217 | |
1218 | rc = HYPERVISOR_grant_table_op(GNTTABOP_set_version, &gsv, 1); | |
83c69324 | 1219 | if (rc == 0 && gsv.version == 2) |
b988b8ff | 1220 | gnttab_interface = &gnttab_v2_ops; |
83c69324 | 1221 | else |
b988b8ff | 1222 | gnttab_interface = &gnttab_v1_ops; |
83c69324 JG |
1223 | pr_info("Grant tables using version %d layout\n", |
1224 | gnttab_interface->version); | |
ad9a8612 JF |
1225 | } |
1226 | ||
d0b4d64a | 1227 | static int gnttab_setup(void) |
ad9a8612 | 1228 | { |
183d03cc SS |
1229 | unsigned int max_nr_gframes; |
1230 | ||
1231 | max_nr_gframes = gnttab_max_grant_frames(); | |
1232 | if (max_nr_gframes < nr_grant_frames) | |
ad9a8612 | 1233 | return -ENOSYS; |
183d03cc | 1234 | |
45684753 | 1235 | if (xen_feature(XENFEAT_auto_translated_physmap) && gnttab_shared.addr == NULL) { |
efaf30a3 | 1236 | gnttab_shared.addr = xen_auto_xlat_grant_frames.vaddr; |
0f9f5a95 | 1237 | if (gnttab_shared.addr == NULL) { |
efaf30a3 KRW |
1238 | pr_warn("gnttab share frames (addr=0x%08lx) is not mapped!\n", |
1239 | (unsigned long)xen_auto_xlat_grant_frames.vaddr); | |
183d03cc SS |
1240 | return -ENOMEM; |
1241 | } | |
1242 | } | |
45684753 | 1243 | return gnttab_map(0, nr_grant_frames - 1); |
ad9a8612 JF |
1244 | } |
1245 | ||
d0b4d64a MW |
1246 | int gnttab_resume(void) |
1247 | { | |
1248 | gnttab_request_version(); | |
1249 | return gnttab_setup(); | |
1250 | } | |
1251 | ||
0e91398f | 1252 | int gnttab_suspend(void) |
ad9a8612 | 1253 | { |
13cd36a3 DV |
1254 | if (!xen_feature(XENFEAT_auto_translated_physmap)) |
1255 | gnttab_interface->unmap_frames(); | |
ad9a8612 JF |
1256 | return 0; |
1257 | } | |
1258 | ||
1259 | static int gnttab_expand(unsigned int req_entries) | |
1260 | { | |
1261 | int rc; | |
1262 | unsigned int cur, extra; | |
1263 | ||
83c69324 | 1264 | BUG_ON(gnttab_interface == NULL); |
ad9a8612 | 1265 | cur = nr_grant_frames; |
83c69324 JG |
1266 | extra = ((req_entries + gnttab_interface->grefs_per_grant_frame - 1) / |
1267 | gnttab_interface->grefs_per_grant_frame); | |
29d11cfd WW |
1268 | if (cur + extra > gnttab_max_grant_frames()) { |
1269 | pr_warn_ratelimited("xen/grant-table: max_grant_frames reached" | |
1270 | " cur=%u extra=%u limit=%u" | |
1271 | " gnttab_free_count=%u req_entries=%u\n", | |
1272 | cur, extra, gnttab_max_grant_frames(), | |
1273 | gnttab_free_count, req_entries); | |
ad9a8612 | 1274 | return -ENOSPC; |
29d11cfd | 1275 | } |
ad9a8612 JF |
1276 | |
1277 | rc = gnttab_map(cur, cur + extra - 1); | |
1278 | if (rc == 0) | |
1279 | rc = grow_gnttab_list(extra); | |
1280 | ||
1281 | return rc; | |
1282 | } | |
1283 | ||
183d03cc | 1284 | int gnttab_init(void) |
ad9a8612 JF |
1285 | { |
1286 | int i; | |
162e3717 | 1287 | unsigned long max_nr_grant_frames; |
bbc60c18 | 1288 | unsigned int max_nr_glist_frames, nr_glist_frames; |
ad9a8612 | 1289 | unsigned int nr_init_grefs; |
6b5e7d9e | 1290 | int ret; |
ad9a8612 | 1291 | |
d0b4d64a | 1292 | gnttab_request_version(); |
162e3717 | 1293 | max_nr_grant_frames = gnttab_max_grant_frames(); |
ad9a8612 | 1294 | nr_grant_frames = 1; |
ad9a8612 JF |
1295 | |
1296 | /* Determine the maximum number of frames required for the | |
1297 | * grant reference free list on the current hypervisor. | |
1298 | */ | |
83c69324 | 1299 | BUG_ON(gnttab_interface == NULL); |
162e3717 | 1300 | max_nr_glist_frames = (max_nr_grant_frames * |
83c69324 | 1301 | gnttab_interface->grefs_per_grant_frame / RPP); |
ad9a8612 JF |
1302 | |
1303 | gnttab_list = kmalloc(max_nr_glist_frames * sizeof(grant_ref_t *), | |
1304 | GFP_KERNEL); | |
1305 | if (gnttab_list == NULL) | |
1306 | return -ENOMEM; | |
1307 | ||
83c69324 | 1308 | nr_glist_frames = gnttab_frames(nr_grant_frames, RPP); |
bbc60c18 | 1309 | for (i = 0; i < nr_glist_frames; i++) { |
ad9a8612 | 1310 | gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_KERNEL); |
6b5e7d9e JL |
1311 | if (gnttab_list[i] == NULL) { |
1312 | ret = -ENOMEM; | |
ad9a8612 | 1313 | goto ini_nomem; |
6b5e7d9e | 1314 | } |
ad9a8612 JF |
1315 | } |
1316 | ||
b988b8ff JG |
1317 | ret = arch_gnttab_init(max_nr_grant_frames, |
1318 | nr_status_frames(max_nr_grant_frames)); | |
162e3717 DV |
1319 | if (ret < 0) |
1320 | goto ini_nomem; | |
1321 | ||
d0b4d64a | 1322 | if (gnttab_setup() < 0) { |
6b5e7d9e JL |
1323 | ret = -ENODEV; |
1324 | goto ini_nomem; | |
1325 | } | |
ad9a8612 | 1326 | |
83c69324 JG |
1327 | nr_init_grefs = nr_grant_frames * |
1328 | gnttab_interface->grefs_per_grant_frame; | |
ad9a8612 JF |
1329 | |
1330 | for (i = NR_RESERVED_ENTRIES; i < nr_init_grefs - 1; i++) | |
1331 | gnttab_entry(i) = i + 1; | |
1332 | ||
1333 | gnttab_entry(nr_init_grefs - 1) = GNTTAB_LIST_END; | |
1334 | gnttab_free_count = nr_init_grefs - NR_RESERVED_ENTRIES; | |
1335 | gnttab_free_head = NR_RESERVED_ENTRIES; | |
1336 | ||
1337 | printk("Grant table initialized\n"); | |
1338 | return 0; | |
1339 | ||
1340 | ini_nomem: | |
1341 | for (i--; i >= 0; i--) | |
1342 | free_page((unsigned long)gnttab_list[i]); | |
1343 | kfree(gnttab_list); | |
6b5e7d9e | 1344 | return ret; |
ad9a8612 | 1345 | } |
183d03cc SS |
1346 | EXPORT_SYMBOL_GPL(gnttab_init); |
1347 | ||
345a5255 | 1348 | static int __gnttab_init(void) |
183d03cc | 1349 | { |
8613d78a BO |
1350 | if (!xen_domain()) |
1351 | return -ENODEV; | |
1352 | ||
183d03cc | 1353 | /* Delay grant-table initialization in the PV on HVM case */ |
8613d78a | 1354 | if (xen_hvm_domain() && !xen_pvh_domain()) |
183d03cc SS |
1355 | return 0; |
1356 | ||
183d03cc SS |
1357 | return gnttab_init(); |
1358 | } | |
6926f6d6 KRW |
1359 | /* Starts after core_initcall so that xen_pvh_gnttab_setup can be called |
1360 | * beforehand to initialize xen_auto_xlat_grant_frames. */ | |
1361 | core_initcall_sync(__gnttab_init); |