blob: bb36b1e1dbcc68fd31490079fcb4e1feee0b70d7 [file] [log] [blame]
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001/******************************************************************************
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
Joe Perches283c0972013-06-28 03:21:41 -070034#define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt
35
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -070036#include <linux/sched.h>
37#include <linux/mm.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090038#include <linux/slab.h>
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -070039#include <linux/vmalloc.h>
40#include <linux/uaccess.h>
Stefano Stabellini183d03c2010-05-17 17:08:21 +010041#include <linux/io.h>
Andres Lagar-Cavillac5718982012-09-14 14:26:59 +000042#include <linux/delay.h>
Stefano Stabellinif62805f2012-04-24 11:55:43 +010043#include <linux/hardirq.h>
Jennifer Herbert3f9f1c62014-12-09 18:28:37 +000044#include <linux/workqueue.h>
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -070045
Jeremy Fitzhardinge1ccbf532009-10-06 15:11:14 -070046#include <xen/xen.h>
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -070047#include <xen/interface/xen.h>
48#include <xen/page.h>
49#include <xen/grant_table.h>
Stefano Stabellini183d03c2010-05-17 17:08:21 +010050#include <xen/interface/memory.h>
Annie Li85ff6ac2011-11-22 09:59:21 +080051#include <xen/hvc-console.h>
Stefano Stabellini3d24bbd2013-10-25 10:41:44 +000052#include <xen/swiotlb-xen.h>
David Vrabelff4b1562015-01-08 18:06:01 +000053#include <xen/balloon.h>
Jeremy Fitzhardingeecbf29c2008-12-16 12:37:07 -080054#include <asm/xen/hypercall.h>
Stefano Stabellini4d9310e2012-08-06 15:27:09 +010055#include <asm/xen/interface.h>
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -070056
57#include <asm/pgtable.h>
58#include <asm/sync_bitops.h>
59
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -070060/* External tools reserve first few grant table entries. */
61#define NR_RESERVED_ENTRIES 8
62#define GNTTAB_LIST_END 0xffffffff
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -070063
64static grant_ref_t **gnttab_list;
65static unsigned int nr_grant_frames;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -070066static int gnttab_free_count;
67static grant_ref_t gnttab_free_head;
68static DEFINE_SPINLOCK(gnttab_list_lock);
Konrad Rzeszutek Wilkefaf30a2014-01-06 10:40:36 -050069struct grant_frames xen_auto_xlat_grant_frames;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -070070
Annie Li0f9f5a92011-11-22 09:58:06 +080071static union {
72 struct grant_entry_v1 *v1;
73 void *addr;
74} gnttab_shared;
75
76/*This is a structure of function pointers for grant table*/
77struct gnttab_ops {
78 /*
Annie Li9dbc71d2011-12-12 18:13:57 +080079 * Mapping a list of frames for storing grant entries. Frames parameter
80 * is used to store grant table address when grant table being setup,
81 * nr_gframes is the number of frames to map grant table. Returning
82 * GNTST_okay means success and negative value means failure.
Annie Li0f9f5a92011-11-22 09:58:06 +080083 */
Ian Campbellef32f892012-10-17 09:39:14 +010084 int (*map_frames)(xen_pfn_t *frames, unsigned int nr_gframes);
Annie Li0f9f5a92011-11-22 09:58:06 +080085 /*
86 * Release a list of frames which are mapped in map_frames for grant
87 * entry status.
88 */
89 void (*unmap_frames)(void);
90 /*
Annie Li9dbc71d2011-12-12 18:13:57 +080091 * Introducing a valid entry into the grant table, granting the frame of
92 * this grant entry to domain for accessing or transfering. Ref
93 * parameter is reference of this introduced grant entry, domid is id of
94 * granted domain, frame is the page frame to be granted, and flags is
95 * status of the grant entry to be updated.
Annie Li0f9f5a92011-11-22 09:58:06 +080096 */
Annie Li9dbc71d2011-12-12 18:13:57 +080097 void (*update_entry)(grant_ref_t ref, domid_t domid,
98 unsigned long frame, unsigned flags);
Annie Li0f9f5a92011-11-22 09:58:06 +080099 /*
Annie Li9dbc71d2011-12-12 18:13:57 +0800100 * Stop granting a grant entry to domain for accessing. Ref parameter is
101 * reference of a grant entry whose grant access will be stopped,
102 * readonly is not in use in this function. If the grant entry is
Annie Li0f9f5a92011-11-22 09:58:06 +0800103 * currently mapped for reading or writing, just return failure(==0)
104 * directly and don't tear down the grant access. Otherwise, stop grant
105 * access for this entry and return success(==1).
106 */
Annie Li9dbc71d2011-12-12 18:13:57 +0800107 int (*end_foreign_access_ref)(grant_ref_t ref, int readonly);
Annie Li0f9f5a92011-11-22 09:58:06 +0800108 /*
Annie Li9dbc71d2011-12-12 18:13:57 +0800109 * Stop granting a grant entry to domain for transfer. Ref parameter is
110 * reference of a grant entry whose grant transfer will be stopped. If
111 * tranfer has not started, just reclaim the grant entry and return
112 * failure(==0). Otherwise, wait for the transfer to complete and then
113 * return the frame.
Annie Li0f9f5a92011-11-22 09:58:06 +0800114 */
Annie Li9dbc71d2011-12-12 18:13:57 +0800115 unsigned long (*end_foreign_transfer_ref)(grant_ref_t ref);
Annie Li0f9f5a92011-11-22 09:58:06 +0800116 /*
Annie Li9dbc71d2011-12-12 18:13:57 +0800117 * Query the status of a grant entry. Ref parameter is reference of
Annie Li0f9f5a92011-11-22 09:58:06 +0800118 * queried grant entry, return value is the status of queried entry.
119 * Detailed status(writing/reading) can be gotten from the return value
120 * by bit operations.
121 */
Annie Li9dbc71d2011-12-12 18:13:57 +0800122 int (*query_foreign_access)(grant_ref_t ref);
Annie Li0f9f5a92011-11-22 09:58:06 +0800123};
124
Bob Liub44166c2015-04-03 14:42:59 +0800125struct unmap_refs_callback_data {
126 struct completion completion;
127 int result;
128};
129
Julia Lawall86fc2132015-11-28 15:28:40 +0100130static const struct gnttab_ops *gnttab_interface;
Annie Li0f9f5a92011-11-22 09:58:06 +0800131
132static int grant_table_version;
Matt Wilsond0b4d642013-01-15 13:21:27 +0000133static int grefs_per_grant_frame;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700134
135static struct gnttab_free_callback *gnttab_free_callback_list;
136
137static int gnttab_expand(unsigned int req_entries);
138
139#define RPP (PAGE_SIZE / sizeof(grant_ref_t))
140
141static inline grant_ref_t *__gnttab_entry(grant_ref_t entry)
142{
143 return &gnttab_list[(entry) / RPP][(entry) % RPP];
144}
145/* This can be used as an l-value */
146#define gnttab_entry(entry) (*__gnttab_entry(entry))
147
148static int get_free_entries(unsigned count)
149{
150 unsigned long flags;
Konrad Rzeszutek Wilk272800d2011-07-22 14:00:06 -0400151 int ref, rc = 0;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700152 grant_ref_t head;
153
154 spin_lock_irqsave(&gnttab_list_lock, flags);
155
156 if ((gnttab_free_count < count) &&
157 ((rc = gnttab_expand(count - gnttab_free_count)) < 0)) {
158 spin_unlock_irqrestore(&gnttab_list_lock, flags);
159 return rc;
160 }
161
162 ref = head = gnttab_free_head;
163 gnttab_free_count -= count;
164 while (count-- > 1)
165 head = gnttab_entry(head);
166 gnttab_free_head = gnttab_entry(head);
167 gnttab_entry(head) = GNTTAB_LIST_END;
168
169 spin_unlock_irqrestore(&gnttab_list_lock, flags);
170
171 return ref;
172}
173
174static void do_free_callbacks(void)
175{
176 struct gnttab_free_callback *callback, *next;
177
178 callback = gnttab_free_callback_list;
179 gnttab_free_callback_list = NULL;
180
181 while (callback != NULL) {
182 next = callback->next;
183 if (gnttab_free_count >= callback->count) {
184 callback->next = NULL;
185 callback->fn(callback->arg);
186 } else {
187 callback->next = gnttab_free_callback_list;
188 gnttab_free_callback_list = callback;
189 }
190 callback = next;
191 }
192}
193
194static inline void check_free_callbacks(void)
195{
196 if (unlikely(gnttab_free_callback_list))
197 do_free_callbacks();
198}
199
200static void put_free_entry(grant_ref_t ref)
201{
202 unsigned long flags;
203 spin_lock_irqsave(&gnttab_list_lock, flags);
204 gnttab_entry(ref) = gnttab_free_head;
205 gnttab_free_head = ref;
206 gnttab_free_count++;
207 check_free_callbacks();
208 spin_unlock_irqrestore(&gnttab_list_lock, flags);
209}
210
Annie Li0f9f5a92011-11-22 09:58:06 +0800211/*
David Vrabel438b33c2014-07-02 11:25:29 +0100212 * Following applies to gnttab_update_entry_v1.
Annie Li0f9f5a92011-11-22 09:58:06 +0800213 * Introducing a valid entry into the grant table:
214 * 1. Write ent->domid.
215 * 2. Write ent->frame:
216 * GTF_permit_access: Frame to which access is permitted.
217 * GTF_accept_transfer: Pseudo-phys frame slot being filled by new
218 * frame, or zero if none.
219 * 3. Write memory barrier (WMB).
220 * 4. Write ent->flags, inc. valid type.
221 */
222static void gnttab_update_entry_v1(grant_ref_t ref, domid_t domid,
223 unsigned long frame, unsigned flags)
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700224{
Annie Li0f9f5a92011-11-22 09:58:06 +0800225 gnttab_shared.v1[ref].domid = domid;
226 gnttab_shared.v1[ref].frame = frame;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700227 wmb();
Annie Li0f9f5a92011-11-22 09:58:06 +0800228 gnttab_shared.v1[ref].flags = flags;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700229}
230
231/*
232 * Public grant-issuing interface functions
233 */
234void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
235 unsigned long frame, int readonly)
236{
Annie Li0f9f5a92011-11-22 09:58:06 +0800237 gnttab_interface->update_entry(ref, domid, frame,
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700238 GTF_permit_access | (readonly ? GTF_readonly : 0));
239}
240EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_ref);
241
242int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
243 int readonly)
244{
245 int ref;
246
247 ref = get_free_entries(1);
248 if (unlikely(ref < 0))
249 return -ENOSPC;
250
251 gnttab_grant_foreign_access_ref(ref, domid, frame, readonly);
252
253 return ref;
254}
255EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access);
256
Annie Li0f9f5a92011-11-22 09:58:06 +0800257static int gnttab_query_foreign_access_v1(grant_ref_t ref)
258{
259 return gnttab_shared.v1[ref].flags & (GTF_reading|GTF_writing);
260}
261
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700262int gnttab_query_foreign_access(grant_ref_t ref)
263{
Annie Li0f9f5a92011-11-22 09:58:06 +0800264 return gnttab_interface->query_foreign_access(ref);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700265}
266EXPORT_SYMBOL_GPL(gnttab_query_foreign_access);
267
Annie Li0f9f5a92011-11-22 09:58:06 +0800268static int gnttab_end_foreign_access_ref_v1(grant_ref_t ref, int readonly)
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700269{
270 u16 flags, nflags;
Annie Lib1e495b2011-11-22 09:58:47 +0800271 u16 *pflags;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700272
Annie Lib1e495b2011-11-22 09:58:47 +0800273 pflags = &gnttab_shared.v1[ref].flags;
274 nflags = *pflags;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700275 do {
276 flags = nflags;
Jan Beulich569ca5b2012-04-05 16:10:07 +0100277 if (flags & (GTF_reading|GTF_writing))
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700278 return 0;
Annie Lib1e495b2011-11-22 09:58:47 +0800279 } while ((nflags = sync_cmpxchg(pflags, flags, 0)) != flags);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700280
281 return 1;
282}
Annie Li0f9f5a92011-11-22 09:58:06 +0800283
Jan Beulich569ca5b2012-04-05 16:10:07 +0100284static inline int _gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly)
Annie Li0f9f5a92011-11-22 09:58:06 +0800285{
286 return gnttab_interface->end_foreign_access_ref(ref, readonly);
287}
Jan Beulich569ca5b2012-04-05 16:10:07 +0100288
289int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly)
290{
291 if (_gnttab_end_foreign_access_ref(ref, readonly))
292 return 1;
293 pr_warn("WARNING: g.e. %#x still in use!\n", ref);
294 return 0;
295}
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700296EXPORT_SYMBOL_GPL(gnttab_end_foreign_access_ref);
297
Jan Beulich569ca5b2012-04-05 16:10:07 +0100298struct deferred_entry {
299 struct list_head list;
300 grant_ref_t ref;
301 bool ro;
302 uint16_t warn_delay;
303 struct page *page;
304};
305static LIST_HEAD(deferred_list);
306static void gnttab_handle_deferred(unsigned long);
307static DEFINE_TIMER(deferred_timer, gnttab_handle_deferred, 0, 0);
308
309static void gnttab_handle_deferred(unsigned long unused)
310{
311 unsigned int nr = 10;
312 struct deferred_entry *first = NULL;
313 unsigned long flags;
314
315 spin_lock_irqsave(&gnttab_list_lock, flags);
316 while (nr--) {
317 struct deferred_entry *entry
318 = list_first_entry(&deferred_list,
319 struct deferred_entry, list);
320
321 if (entry == first)
322 break;
323 list_del(&entry->list);
324 spin_unlock_irqrestore(&gnttab_list_lock, flags);
325 if (_gnttab_end_foreign_access_ref(entry->ref, entry->ro)) {
326 put_free_entry(entry->ref);
327 if (entry->page) {
328 pr_debug("freeing g.e. %#x (pfn %#lx)\n",
329 entry->ref, page_to_pfn(entry->page));
330 __free_page(entry->page);
331 } else
332 pr_info("freeing g.e. %#x\n", entry->ref);
333 kfree(entry);
334 entry = NULL;
335 } else {
336 if (!--entry->warn_delay)
Joe Perches283c0972013-06-28 03:21:41 -0700337 pr_info("g.e. %#x still pending\n", entry->ref);
Jan Beulich569ca5b2012-04-05 16:10:07 +0100338 if (!first)
339 first = entry;
340 }
341 spin_lock_irqsave(&gnttab_list_lock, flags);
342 if (entry)
343 list_add_tail(&entry->list, &deferred_list);
344 else if (list_empty(&deferred_list))
345 break;
346 }
347 if (!list_empty(&deferred_list) && !timer_pending(&deferred_timer)) {
348 deferred_timer.expires = jiffies + HZ;
349 add_timer(&deferred_timer);
350 }
351 spin_unlock_irqrestore(&gnttab_list_lock, flags);
352}
353
354static void gnttab_add_deferred(grant_ref_t ref, bool readonly,
355 struct page *page)
356{
357 struct deferred_entry *entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
358 const char *what = KERN_WARNING "leaking";
359
360 if (entry) {
361 unsigned long flags;
362
363 entry->ref = ref;
364 entry->ro = readonly;
365 entry->page = page;
366 entry->warn_delay = 60;
367 spin_lock_irqsave(&gnttab_list_lock, flags);
368 list_add_tail(&entry->list, &deferred_list);
369 if (!timer_pending(&deferred_timer)) {
370 deferred_timer.expires = jiffies + HZ;
371 add_timer(&deferred_timer);
372 }
373 spin_unlock_irqrestore(&gnttab_list_lock, flags);
374 what = KERN_DEBUG "deferring";
375 }
376 printk("%s g.e. %#x (pfn %#lx)\n",
377 what, ref, page ? page_to_pfn(page) : -1);
378}
379
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700380void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
381 unsigned long page)
382{
383 if (gnttab_end_foreign_access_ref(ref, readonly)) {
384 put_free_entry(ref);
385 if (page != 0)
386 free_page(page);
Jan Beulich569ca5b2012-04-05 16:10:07 +0100387 } else
388 gnttab_add_deferred(ref, readonly,
389 page ? virt_to_page(page) : NULL);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700390}
391EXPORT_SYMBOL_GPL(gnttab_end_foreign_access);
392
393int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn)
394{
395 int ref;
396
397 ref = get_free_entries(1);
398 if (unlikely(ref < 0))
399 return -ENOSPC;
400 gnttab_grant_foreign_transfer_ref(ref, domid, pfn);
401
402 return ref;
403}
404EXPORT_SYMBOL_GPL(gnttab_grant_foreign_transfer);
405
406void gnttab_grant_foreign_transfer_ref(grant_ref_t ref, domid_t domid,
407 unsigned long pfn)
408{
Annie Li0f9f5a92011-11-22 09:58:06 +0800409 gnttab_interface->update_entry(ref, domid, pfn, GTF_accept_transfer);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700410}
411EXPORT_SYMBOL_GPL(gnttab_grant_foreign_transfer_ref);
412
Annie Li0f9f5a92011-11-22 09:58:06 +0800413static unsigned long gnttab_end_foreign_transfer_ref_v1(grant_ref_t ref)
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700414{
415 unsigned long frame;
416 u16 flags;
Annie Lib1e495b2011-11-22 09:58:47 +0800417 u16 *pflags;
418
419 pflags = &gnttab_shared.v1[ref].flags;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700420
421 /*
422 * If a transfer is not even yet started, try to reclaim the grant
423 * reference and return failure (== 0).
424 */
Annie Lib1e495b2011-11-22 09:58:47 +0800425 while (!((flags = *pflags) & GTF_transfer_committed)) {
426 if (sync_cmpxchg(pflags, flags, 0) == flags)
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700427 return 0;
428 cpu_relax();
429 }
430
431 /* If a transfer is in progress then wait until it is completed. */
432 while (!(flags & GTF_transfer_completed)) {
Annie Lib1e495b2011-11-22 09:58:47 +0800433 flags = *pflags;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700434 cpu_relax();
435 }
436
437 rmb(); /* Read the frame number /after/ reading completion status. */
Annie Li0f9f5a92011-11-22 09:58:06 +0800438 frame = gnttab_shared.v1[ref].frame;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700439 BUG_ON(frame == 0);
440
441 return frame;
442}
Annie Li0f9f5a92011-11-22 09:58:06 +0800443
444unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref)
445{
446 return gnttab_interface->end_foreign_transfer_ref(ref);
447}
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700448EXPORT_SYMBOL_GPL(gnttab_end_foreign_transfer_ref);
449
450unsigned long gnttab_end_foreign_transfer(grant_ref_t ref)
451{
452 unsigned long frame = gnttab_end_foreign_transfer_ref(ref);
453 put_free_entry(ref);
454 return frame;
455}
456EXPORT_SYMBOL_GPL(gnttab_end_foreign_transfer);
457
458void gnttab_free_grant_reference(grant_ref_t ref)
459{
460 put_free_entry(ref);
461}
462EXPORT_SYMBOL_GPL(gnttab_free_grant_reference);
463
464void gnttab_free_grant_references(grant_ref_t head)
465{
466 grant_ref_t ref;
467 unsigned long flags;
468 int count = 1;
469 if (head == GNTTAB_LIST_END)
470 return;
471 spin_lock_irqsave(&gnttab_list_lock, flags);
472 ref = head;
473 while (gnttab_entry(ref) != GNTTAB_LIST_END) {
474 ref = gnttab_entry(ref);
475 count++;
476 }
477 gnttab_entry(ref) = gnttab_free_head;
478 gnttab_free_head = head;
479 gnttab_free_count += count;
480 check_free_callbacks();
481 spin_unlock_irqrestore(&gnttab_list_lock, flags);
482}
483EXPORT_SYMBOL_GPL(gnttab_free_grant_references);
484
485int gnttab_alloc_grant_references(u16 count, grant_ref_t *head)
486{
487 int h = get_free_entries(count);
488
489 if (h < 0)
490 return -ENOSPC;
491
492 *head = h;
493
494 return 0;
495}
496EXPORT_SYMBOL_GPL(gnttab_alloc_grant_references);
497
498int gnttab_empty_grant_references(const grant_ref_t *private_head)
499{
500 return (*private_head == GNTTAB_LIST_END);
501}
502EXPORT_SYMBOL_GPL(gnttab_empty_grant_references);
503
504int gnttab_claim_grant_reference(grant_ref_t *private_head)
505{
506 grant_ref_t g = *private_head;
507 if (unlikely(g == GNTTAB_LIST_END))
508 return -ENOSPC;
509 *private_head = gnttab_entry(g);
510 return g;
511}
512EXPORT_SYMBOL_GPL(gnttab_claim_grant_reference);
513
514void gnttab_release_grant_reference(grant_ref_t *private_head,
515 grant_ref_t release)
516{
517 gnttab_entry(release) = *private_head;
518 *private_head = release;
519}
520EXPORT_SYMBOL_GPL(gnttab_release_grant_reference);
521
522void gnttab_request_free_callback(struct gnttab_free_callback *callback,
523 void (*fn)(void *), void *arg, u16 count)
524{
525 unsigned long flags;
Roger Pau Monne5f338d92013-07-31 17:00:42 +0200526 struct gnttab_free_callback *cb;
527
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700528 spin_lock_irqsave(&gnttab_list_lock, flags);
Roger Pau Monne5f338d92013-07-31 17:00:42 +0200529
530 /* Check if the callback is already on the list */
531 cb = gnttab_free_callback_list;
532 while (cb) {
533 if (cb == callback)
534 goto out;
535 cb = cb->next;
536 }
537
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700538 callback->fn = fn;
539 callback->arg = arg;
540 callback->count = count;
541 callback->next = gnttab_free_callback_list;
542 gnttab_free_callback_list = callback;
543 check_free_callbacks();
544out:
545 spin_unlock_irqrestore(&gnttab_list_lock, flags);
546}
547EXPORT_SYMBOL_GPL(gnttab_request_free_callback);
548
549void gnttab_cancel_free_callback(struct gnttab_free_callback *callback)
550{
551 struct gnttab_free_callback **pcb;
552 unsigned long flags;
553
554 spin_lock_irqsave(&gnttab_list_lock, flags);
555 for (pcb = &gnttab_free_callback_list; *pcb; pcb = &(*pcb)->next) {
556 if (*pcb == callback) {
557 *pcb = callback->next;
558 break;
559 }
560 }
561 spin_unlock_irqrestore(&gnttab_list_lock, flags);
562}
563EXPORT_SYMBOL_GPL(gnttab_cancel_free_callback);
564
565static int grow_gnttab_list(unsigned int more_frames)
566{
567 unsigned int new_nr_grant_frames, extra_entries, i;
Michael Abd-El-Malekbbc60c12008-04-04 02:33:48 -0700568 unsigned int nr_glist_frames, new_nr_glist_frames;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700569
Matt Wilsond0b4d642013-01-15 13:21:27 +0000570 BUG_ON(grefs_per_grant_frame == 0);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700571
Matt Wilsond0b4d642013-01-15 13:21:27 +0000572 new_nr_grant_frames = nr_grant_frames + more_frames;
573 extra_entries = more_frames * grefs_per_grant_frame;
574
575 nr_glist_frames = (nr_grant_frames * grefs_per_grant_frame + RPP - 1) / RPP;
Michael Abd-El-Malekbbc60c12008-04-04 02:33:48 -0700576 new_nr_glist_frames =
Matt Wilsond0b4d642013-01-15 13:21:27 +0000577 (new_nr_grant_frames * grefs_per_grant_frame + RPP - 1) / RPP;
Michael Abd-El-Malekbbc60c12008-04-04 02:33:48 -0700578 for (i = nr_glist_frames; i < new_nr_glist_frames; i++) {
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700579 gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_ATOMIC);
580 if (!gnttab_list[i])
581 goto grow_nomem;
582 }
583
584
Matt Wilsond0b4d642013-01-15 13:21:27 +0000585 for (i = grefs_per_grant_frame * nr_grant_frames;
586 i < grefs_per_grant_frame * new_nr_grant_frames - 1; i++)
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700587 gnttab_entry(i) = i + 1;
588
589 gnttab_entry(i) = gnttab_free_head;
Matt Wilsond0b4d642013-01-15 13:21:27 +0000590 gnttab_free_head = grefs_per_grant_frame * nr_grant_frames;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700591 gnttab_free_count += extra_entries;
592
593 nr_grant_frames = new_nr_grant_frames;
594
595 check_free_callbacks();
596
597 return 0;
598
599grow_nomem:
Chen Gang46e36262014-08-26 23:38:44 +0800600 while (i-- > nr_glist_frames)
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700601 free_page((unsigned long) gnttab_list[i]);
602 return -ENOMEM;
603}
604
605static unsigned int __max_nr_grant_frames(void)
606{
607 struct gnttab_query_size query;
608 int rc;
609
610 query.dom = DOMID_SELF;
611
612 rc = HYPERVISOR_grant_table_op(GNTTABOP_query_size, &query, 1);
613 if ((rc < 0) || (query.status != GNTST_okay))
614 return 4; /* Legacy max supported number of frames */
615
616 return query.max_nr_frames;
617}
618
Stefano Stabellini183d03c2010-05-17 17:08:21 +0100619unsigned int gnttab_max_grant_frames(void)
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700620{
621 unsigned int xen_max = __max_nr_grant_frames();
Konrad Rzeszutek Wilk7f256022013-12-31 15:55:39 -0500622 static unsigned int boot_max_nr_grant_frames;
623
624 /* First time, initialize it properly. */
625 if (!boot_max_nr_grant_frames)
626 boot_max_nr_grant_frames = __max_nr_grant_frames();
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700627
628 if (xen_max > boot_max_nr_grant_frames)
629 return boot_max_nr_grant_frames;
630 return xen_max;
631}
Stefano Stabellini183d03c2010-05-17 17:08:21 +0100632EXPORT_SYMBOL_GPL(gnttab_max_grant_frames);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700633
Julien Grall47c54202014-01-30 12:56:34 +0000634int gnttab_setup_auto_xlat_frames(phys_addr_t addr)
Konrad Rzeszutek Wilkefaf30a2014-01-06 10:40:36 -0500635{
636 xen_pfn_t *pfn;
637 unsigned int max_nr_gframes = __max_nr_grant_frames();
638 unsigned int i;
639 void *vaddr;
640
641 if (xen_auto_xlat_grant_frames.count)
642 return -EINVAL;
643
Julien Grall5ed54512015-05-05 16:37:49 +0100644 vaddr = xen_remap(addr, XEN_PAGE_SIZE * max_nr_gframes);
Konrad Rzeszutek Wilkefaf30a2014-01-06 10:40:36 -0500645 if (vaddr == NULL) {
Julien Grall47c54202014-01-30 12:56:34 +0000646 pr_warn("Failed to ioremap gnttab share frames (addr=%pa)!\n",
647 &addr);
Konrad Rzeszutek Wilkefaf30a2014-01-06 10:40:36 -0500648 return -ENOMEM;
649 }
650 pfn = kcalloc(max_nr_gframes, sizeof(pfn[0]), GFP_KERNEL);
651 if (!pfn) {
652 xen_unmap(vaddr);
653 return -ENOMEM;
654 }
655 for (i = 0; i < max_nr_gframes; i++)
Julien Grall5ed54512015-05-05 16:37:49 +0100656 pfn[i] = XEN_PFN_DOWN(addr) + i;
Konrad Rzeszutek Wilkefaf30a2014-01-06 10:40:36 -0500657
658 xen_auto_xlat_grant_frames.vaddr = vaddr;
659 xen_auto_xlat_grant_frames.pfn = pfn;
660 xen_auto_xlat_grant_frames.count = max_nr_gframes;
661
662 return 0;
663}
664EXPORT_SYMBOL_GPL(gnttab_setup_auto_xlat_frames);
665
666void gnttab_free_auto_xlat_frames(void)
667{
668 if (!xen_auto_xlat_grant_frames.count)
669 return;
670 kfree(xen_auto_xlat_grant_frames.pfn);
671 xen_unmap(xen_auto_xlat_grant_frames.vaddr);
672
673 xen_auto_xlat_grant_frames.pfn = NULL;
674 xen_auto_xlat_grant_frames.count = 0;
675 xen_auto_xlat_grant_frames.vaddr = NULL;
676}
677EXPORT_SYMBOL_GPL(gnttab_free_auto_xlat_frames);
678
David Vrabelff4b1562015-01-08 18:06:01 +0000679/**
680 * gnttab_alloc_pages - alloc pages suitable for grant mapping into
681 * @nr_pages: number of pages to alloc
682 * @pages: returns the pages
683 */
684int gnttab_alloc_pages(int nr_pages, struct page **pages)
685{
Jennifer Herbert8da76332014-12-24 14:17:06 +0000686 int i;
David Vrabelff4b1562015-01-08 18:06:01 +0000687 int ret;
688
David Vrabel81b286e2015-06-25 13:12:46 +0100689 ret = alloc_xenballooned_pages(nr_pages, pages);
David Vrabelff4b1562015-01-08 18:06:01 +0000690 if (ret < 0)
691 return ret;
692
Jennifer Herbert8da76332014-12-24 14:17:06 +0000693 for (i = 0; i < nr_pages; i++) {
694#if BITS_PER_LONG < 64
695 struct xen_page_foreign *foreign;
696
697 foreign = kzalloc(sizeof(*foreign), GFP_KERNEL);
698 if (!foreign) {
699 gnttab_free_pages(nr_pages, pages);
700 return -ENOMEM;
701 }
702 set_page_private(pages[i], (unsigned long)foreign);
703#endif
704 SetPagePrivate(pages[i]);
705 }
706
David Vrabelff4b1562015-01-08 18:06:01 +0000707 return 0;
708}
709EXPORT_SYMBOL(gnttab_alloc_pages);
710
711/**
712 * gnttab_free_pages - free pages allocated by gnttab_alloc_pages()
713 * @nr_pages; number of pages to free
714 * @pages: the pages
715 */
716void gnttab_free_pages(int nr_pages, struct page **pages)
717{
Jennifer Herbert8da76332014-12-24 14:17:06 +0000718 int i;
719
720 for (i = 0; i < nr_pages; i++) {
721 if (PagePrivate(pages[i])) {
722#if BITS_PER_LONG < 64
723 kfree((void *)page_private(pages[i]));
724#endif
725 ClearPagePrivate(pages[i]);
726 }
727 }
David Vrabelff4b1562015-01-08 18:06:01 +0000728 free_xenballooned_pages(nr_pages, pages);
729}
730EXPORT_SYMBOL(gnttab_free_pages);
731
Andres Lagar-Cavillac5718982012-09-14 14:26:59 +0000732/* Handling of paged out grant targets (GNTST_eagain) */
733#define MAX_DELAY 256
734static inline void
735gnttab_retry_eagain_gop(unsigned int cmd, void *gop, int16_t *status,
736 const char *func)
737{
738 unsigned delay = 1;
739
740 do {
741 BUG_ON(HYPERVISOR_grant_table_op(cmd, gop, 1));
742 if (*status == GNTST_eagain)
743 msleep(delay++);
744 } while ((*status == GNTST_eagain) && (delay < MAX_DELAY));
745
746 if (delay >= MAX_DELAY) {
Joe Perches283c0972013-06-28 03:21:41 -0700747 pr_err("%s: %s eagain grant\n", func, current->comm);
Andres Lagar-Cavillac5718982012-09-14 14:26:59 +0000748 *status = GNTST_bad_page;
749 }
750}
751
752void gnttab_batch_map(struct gnttab_map_grant_ref *batch, unsigned count)
753{
754 struct gnttab_map_grant_ref *op;
755
756 if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, batch, count))
757 BUG();
758 for (op = batch; op < batch + count; op++)
759 if (op->status == GNTST_eagain)
760 gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref, op,
761 &op->status, __func__);
762}
763EXPORT_SYMBOL_GPL(gnttab_batch_map);
764
765void gnttab_batch_copy(struct gnttab_copy *batch, unsigned count)
766{
767 struct gnttab_copy *op;
768
769 if (HYPERVISOR_grant_table_op(GNTTABOP_copy, batch, count))
770 BUG();
771 for (op = batch; op < batch + count; op++)
772 if (op->status == GNTST_eagain)
773 gnttab_retry_eagain_gop(GNTTABOP_copy, op,
774 &op->status, __func__);
775}
776EXPORT_SYMBOL_GPL(gnttab_batch_copy);
777
Julien Grall008c3202015-06-19 17:49:03 +0100778void gnttab_foreach_grant_in_range(struct page *page,
779 unsigned int offset,
780 unsigned int len,
781 xen_grant_fn_t fn,
782 void *data)
783{
784 unsigned int goffset;
785 unsigned int glen;
786 unsigned long xen_pfn;
787
788 len = min_t(unsigned int, PAGE_SIZE - offset, len);
789 goffset = xen_offset_in_page(offset);
790
791 xen_pfn = page_to_xen_pfn(page) + XEN_PFN_DOWN(offset);
792
793 while (len) {
794 glen = min_t(unsigned int, XEN_PAGE_SIZE - goffset, len);
795 fn(pfn_to_gfn(xen_pfn), goffset, glen, data);
796
797 goffset = 0;
798 xen_pfn++;
799 len -= glen;
800 }
801}
802EXPORT_SYMBOL_GPL(gnttab_foreach_grant_in_range);
803
Julien Grallf73314b2015-10-13 17:50:12 +0100804void gnttab_foreach_grant(struct page **pages,
805 unsigned int nr_grefs,
806 xen_grant_fn_t fn,
807 void *data)
808{
809 unsigned int goffset = 0;
810 unsigned long xen_pfn = 0;
811 unsigned int i;
812
813 for (i = 0; i < nr_grefs; i++) {
814 if ((i % XEN_PFN_PER_PAGE) == 0) {
815 xen_pfn = page_to_xen_pfn(pages[i / XEN_PFN_PER_PAGE]);
816 goffset = 0;
817 }
818
819 fn(pfn_to_gfn(xen_pfn), goffset, XEN_PAGE_SIZE, data);
820
821 goffset += XEN_PAGE_SIZE;
822 xen_pfn++;
823 }
824}
825
Konrad Rzeszutek Wilke85fc982014-02-03 06:43:59 -0500826int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
Annie Lic1237992011-11-22 09:59:56 +0800827 struct gnttab_map_grant_ref *kmap_ops,
Konrad Rzeszutek Wilke85fc982014-02-03 06:43:59 -0500828 struct page **pages, unsigned int count)
Stefano Stabellini289b7772010-12-10 14:54:44 +0000829{
830 int i, ret;
Stefano Stabellini289b7772010-12-10 14:54:44 +0000831
832 ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, map_ops, count);
Jeremy Fitzhardinge87f1d402010-12-13 14:42:30 +0000833 if (ret)
834 return ret;
Stefano Stabellini289b7772010-12-10 14:54:44 +0000835
Jennifer Herbert8da76332014-12-24 14:17:06 +0000836 for (i = 0; i < count; i++) {
837 /* Retry eagain maps */
Andres Lagar-Cavillac5718982012-09-14 14:26:59 +0000838 if (map_ops[i].status == GNTST_eagain)
839 gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref, map_ops + i,
840 &map_ops[i].status, __func__);
841
Jennifer Herbert8da76332014-12-24 14:17:06 +0000842 if (map_ops[i].status == GNTST_okay) {
843 struct xen_page_foreign *foreign;
844
845 SetPageForeign(pages[i]);
846 foreign = xen_page_foreign(pages[i]);
847 foreign->domid = map_ops[i].dom;
848 foreign->gref = map_ops[i].ref;
849 }
850 }
851
Zoltan Kiss1429d462014-02-27 15:55:30 +0000852 return set_foreign_p2m_mapping(map_ops, kmap_ops, pages, count);
Stefano Stabellini289b7772010-12-10 14:54:44 +0000853}
854EXPORT_SYMBOL_GPL(gnttab_map_refs);
855
Konrad Rzeszutek Wilke85fc982014-02-03 06:43:59 -0500856int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
David Vrabel853d0282015-01-05 14:13:41 +0000857 struct gnttab_unmap_grant_ref *kunmap_ops,
Konrad Rzeszutek Wilke85fc982014-02-03 06:43:59 -0500858 struct page **pages, unsigned int count)
Stefano Stabellini289b7772010-12-10 14:54:44 +0000859{
Jennifer Herbert8da76332014-12-24 14:17:06 +0000860 unsigned int i;
Zoltan Kiss1429d462014-02-27 15:55:30 +0000861 int ret;
Stefano Stabellini289b7772010-12-10 14:54:44 +0000862
863 ret = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap_ops, count);
Jeremy Fitzhardinge87f1d402010-12-13 14:42:30 +0000864 if (ret)
865 return ret;
866
Jennifer Herbert8da76332014-12-24 14:17:06 +0000867 for (i = 0; i < count; i++)
868 ClearPageForeign(pages[i]);
869
David Vrabel853d0282015-01-05 14:13:41 +0000870 return clear_foreign_p2m_mapping(unmap_ops, kunmap_ops, pages, count);
Stefano Stabellini289b7772010-12-10 14:54:44 +0000871}
872EXPORT_SYMBOL_GPL(gnttab_unmap_refs);
873
Jennifer Herbert3f9f1c62014-12-09 18:28:37 +0000874#define GNTTAB_UNMAP_REFS_DELAY 5
875
876static void __gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item);
877
878static void gnttab_unmap_work(struct work_struct *work)
879{
880 struct gntab_unmap_queue_data
881 *unmap_data = container_of(work,
882 struct gntab_unmap_queue_data,
883 gnttab_work.work);
884 if (unmap_data->age != UINT_MAX)
885 unmap_data->age++;
886 __gnttab_unmap_refs_async(unmap_data);
887}
888
889static void __gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item)
890{
891 int ret;
892 int pc;
893
894 for (pc = 0; pc < item->count; pc++) {
895 if (page_count(item->pages[pc]) > 1) {
896 unsigned long delay = GNTTAB_UNMAP_REFS_DELAY * (item->age + 1);
897 schedule_delayed_work(&item->gnttab_work,
898 msecs_to_jiffies(delay));
899 return;
900 }
901 }
902
903 ret = gnttab_unmap_refs(item->unmap_ops, item->kunmap_ops,
904 item->pages, item->count);
905 item->done(ret, item);
906}
907
908void gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item)
909{
910 INIT_DELAYED_WORK(&item->gnttab_work, gnttab_unmap_work);
911 item->age = 0;
912
913 __gnttab_unmap_refs_async(item);
914}
915EXPORT_SYMBOL_GPL(gnttab_unmap_refs_async);
916
Bob Liub44166c2015-04-03 14:42:59 +0800917static void unmap_refs_callback(int result,
918 struct gntab_unmap_queue_data *data)
919{
920 struct unmap_refs_callback_data *d = data->data;
921
922 d->result = result;
923 complete(&d->completion);
924}
925
926int gnttab_unmap_refs_sync(struct gntab_unmap_queue_data *item)
927{
928 struct unmap_refs_callback_data data;
929
930 init_completion(&data.completion);
931 item->data = &data;
932 item->done = &unmap_refs_callback;
933 gnttab_unmap_refs_async(item);
934 wait_for_completion(&data.completion);
935
936 return data.result;
937}
938EXPORT_SYMBOL_GPL(gnttab_unmap_refs_sync);
939
Ian Campbellef32f892012-10-17 09:39:14 +0100940static int gnttab_map_frames_v1(xen_pfn_t *frames, unsigned int nr_gframes)
Annie Li0f9f5a92011-11-22 09:58:06 +0800941{
942 int rc;
943
944 rc = arch_gnttab_map_shared(frames, nr_gframes,
945 gnttab_max_grant_frames(),
946 &gnttab_shared.addr);
947 BUG_ON(rc);
948
949 return 0;
950}
951
952static void gnttab_unmap_frames_v1(void)
953{
Annie Li85ff6ac2011-11-22 09:59:21 +0800954 arch_gnttab_unmap(gnttab_shared.addr, nr_grant_frames);
955}
956
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700957static int gnttab_map(unsigned int start_idx, unsigned int end_idx)
958{
959 struct gnttab_setup_table setup;
Ian Campbellef32f892012-10-17 09:39:14 +0100960 xen_pfn_t *frames;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700961 unsigned int nr_gframes = end_idx + 1;
962 int rc;
963
Konrad Rzeszutek Wilk6926f6d2014-01-03 10:20:18 -0500964 if (xen_feature(XENFEAT_auto_translated_physmap)) {
Stefano Stabellini183d03c2010-05-17 17:08:21 +0100965 struct xen_add_to_physmap xatp;
966 unsigned int i = end_idx;
967 rc = 0;
Konrad Rzeszutek Wilkefaf30a2014-01-06 10:40:36 -0500968 BUG_ON(xen_auto_xlat_grant_frames.count < nr_gframes);
Stefano Stabellini183d03c2010-05-17 17:08:21 +0100969 /*
970 * Loop backwards, so that the first hypercall has the largest
971 * index, ensuring that the table will grow only once.
972 */
973 do {
974 xatp.domid = DOMID_SELF;
975 xatp.idx = i;
976 xatp.space = XENMAPSPACE_grant_table;
Konrad Rzeszutek Wilkefaf30a2014-01-06 10:40:36 -0500977 xatp.gpfn = xen_auto_xlat_grant_frames.pfn[i];
Stefano Stabellini183d03c2010-05-17 17:08:21 +0100978 rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp);
979 if (rc != 0) {
Joe Perches283c0972013-06-28 03:21:41 -0700980 pr_warn("grant table add_to_physmap failed, err=%d\n",
981 rc);
Stefano Stabellini183d03c2010-05-17 17:08:21 +0100982 break;
983 }
984 } while (i-- > start_idx);
985
986 return rc;
987 }
988
Annie Li85ff6ac2011-11-22 09:59:21 +0800989 /* No need for kzalloc as it is initialized in following hypercall
990 * GNTTABOP_setup_table.
991 */
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700992 frames = kmalloc(nr_gframes * sizeof(unsigned long), GFP_ATOMIC);
993 if (!frames)
994 return -ENOMEM;
995
996 setup.dom = DOMID_SELF;
997 setup.nr_frames = nr_gframes;
Isaku Yamahata87e27cf2008-04-02 10:53:52 -0700998 set_xen_guest_handle(setup.frame_list, frames);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -0700999
1000 rc = HYPERVISOR_grant_table_op(GNTTABOP_setup_table, &setup, 1);
1001 if (rc == -ENOSYS) {
1002 kfree(frames);
1003 return -ENOSYS;
1004 }
1005
1006 BUG_ON(rc || setup.status);
1007
Annie Li0f9f5a92011-11-22 09:58:06 +08001008 rc = gnttab_interface->map_frames(frames, nr_gframes);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001009
1010 kfree(frames);
1011
Annie Li0f9f5a92011-11-22 09:58:06 +08001012 return rc;
1013}
1014
Julia Lawall86fc2132015-11-28 15:28:40 +01001015static const struct gnttab_ops gnttab_v1_ops = {
Annie Li0f9f5a92011-11-22 09:58:06 +08001016 .map_frames = gnttab_map_frames_v1,
1017 .unmap_frames = gnttab_unmap_frames_v1,
1018 .update_entry = gnttab_update_entry_v1,
1019 .end_foreign_access_ref = gnttab_end_foreign_access_ref_v1,
1020 .end_foreign_transfer_ref = gnttab_end_foreign_transfer_ref_v1,
1021 .query_foreign_access = gnttab_query_foreign_access_v1,
1022};
1023
1024static void gnttab_request_version(void)
1025{
David Vrabel438b33c2014-07-02 11:25:29 +01001026 /* Only version 1 is used, which will always be available. */
1027 grant_table_version = 1;
Julien Grall5ed54512015-05-05 16:37:49 +01001028 grefs_per_grant_frame = XEN_PAGE_SIZE / sizeof(struct grant_entry_v1);
David Vrabel438b33c2014-07-02 11:25:29 +01001029 gnttab_interface = &gnttab_v1_ops;
Annie Li85ff6ac2011-11-22 09:59:21 +08001030
Joe Perches283c0972013-06-28 03:21:41 -07001031 pr_info("Grant tables using version %d layout\n", grant_table_version);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001032}
1033
Matt Wilsond0b4d642013-01-15 13:21:27 +00001034static int gnttab_setup(void)
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001035{
Stefano Stabellini183d03c2010-05-17 17:08:21 +01001036 unsigned int max_nr_gframes;
1037
1038 max_nr_gframes = gnttab_max_grant_frames();
1039 if (max_nr_gframes < nr_grant_frames)
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001040 return -ENOSYS;
Stefano Stabellini183d03c2010-05-17 17:08:21 +01001041
Konrad Rzeszutek Wilk45684752013-12-31 16:33:31 -05001042 if (xen_feature(XENFEAT_auto_translated_physmap) && gnttab_shared.addr == NULL) {
Konrad Rzeszutek Wilkefaf30a2014-01-06 10:40:36 -05001043 gnttab_shared.addr = xen_auto_xlat_grant_frames.vaddr;
Annie Li0f9f5a92011-11-22 09:58:06 +08001044 if (gnttab_shared.addr == NULL) {
Konrad Rzeszutek Wilkefaf30a2014-01-06 10:40:36 -05001045 pr_warn("gnttab share frames (addr=0x%08lx) is not mapped!\n",
1046 (unsigned long)xen_auto_xlat_grant_frames.vaddr);
Stefano Stabellini183d03c2010-05-17 17:08:21 +01001047 return -ENOMEM;
1048 }
1049 }
Konrad Rzeszutek Wilk45684752013-12-31 16:33:31 -05001050 return gnttab_map(0, nr_grant_frames - 1);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001051}
1052
Matt Wilsond0b4d642013-01-15 13:21:27 +00001053int gnttab_resume(void)
1054{
1055 gnttab_request_version();
1056 return gnttab_setup();
1057}
1058
Jeremy Fitzhardinge0e913982008-05-26 23:31:27 +01001059int gnttab_suspend(void)
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001060{
David Vrabel13cd36a2014-06-16 11:12:03 +01001061 if (!xen_feature(XENFEAT_auto_translated_physmap))
1062 gnttab_interface->unmap_frames();
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001063 return 0;
1064}
1065
1066static int gnttab_expand(unsigned int req_entries)
1067{
1068 int rc;
1069 unsigned int cur, extra;
1070
Matt Wilsond0b4d642013-01-15 13:21:27 +00001071 BUG_ON(grefs_per_grant_frame == 0);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001072 cur = nr_grant_frames;
Matt Wilsond0b4d642013-01-15 13:21:27 +00001073 extra = ((req_entries + (grefs_per_grant_frame-1)) /
1074 grefs_per_grant_frame);
Stefano Stabellini183d03c2010-05-17 17:08:21 +01001075 if (cur + extra > gnttab_max_grant_frames())
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001076 return -ENOSPC;
1077
1078 rc = gnttab_map(cur, cur + extra - 1);
1079 if (rc == 0)
1080 rc = grow_gnttab_list(extra);
1081
1082 return rc;
1083}
1084
Stefano Stabellini183d03c2010-05-17 17:08:21 +01001085int gnttab_init(void)
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001086{
1087 int i;
David Vrabel162e3712014-07-11 16:42:34 +01001088 unsigned long max_nr_grant_frames;
Michael Abd-El-Malekbbc60c12008-04-04 02:33:48 -07001089 unsigned int max_nr_glist_frames, nr_glist_frames;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001090 unsigned int nr_init_grefs;
Julia Lawall6b5e7d92012-04-15 11:27:12 +02001091 int ret;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001092
Matt Wilsond0b4d642013-01-15 13:21:27 +00001093 gnttab_request_version();
David Vrabel162e3712014-07-11 16:42:34 +01001094 max_nr_grant_frames = gnttab_max_grant_frames();
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001095 nr_grant_frames = 1;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001096
1097 /* Determine the maximum number of frames required for the
1098 * grant reference free list on the current hypervisor.
1099 */
Matt Wilsond0b4d642013-01-15 13:21:27 +00001100 BUG_ON(grefs_per_grant_frame == 0);
David Vrabel162e3712014-07-11 16:42:34 +01001101 max_nr_glist_frames = (max_nr_grant_frames *
Matt Wilsond0b4d642013-01-15 13:21:27 +00001102 grefs_per_grant_frame / RPP);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001103
1104 gnttab_list = kmalloc(max_nr_glist_frames * sizeof(grant_ref_t *),
1105 GFP_KERNEL);
1106 if (gnttab_list == NULL)
1107 return -ENOMEM;
1108
Matt Wilsond0b4d642013-01-15 13:21:27 +00001109 nr_glist_frames = (nr_grant_frames * grefs_per_grant_frame + RPP - 1) / RPP;
Michael Abd-El-Malekbbc60c12008-04-04 02:33:48 -07001110 for (i = 0; i < nr_glist_frames; i++) {
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001111 gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_KERNEL);
Julia Lawall6b5e7d92012-04-15 11:27:12 +02001112 if (gnttab_list[i] == NULL) {
1113 ret = -ENOMEM;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001114 goto ini_nomem;
Julia Lawall6b5e7d92012-04-15 11:27:12 +02001115 }
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001116 }
1117
David Vrabel438b33c2014-07-02 11:25:29 +01001118 ret = arch_gnttab_init(max_nr_grant_frames);
David Vrabel162e3712014-07-11 16:42:34 +01001119 if (ret < 0)
1120 goto ini_nomem;
1121
Matt Wilsond0b4d642013-01-15 13:21:27 +00001122 if (gnttab_setup() < 0) {
Julia Lawall6b5e7d92012-04-15 11:27:12 +02001123 ret = -ENODEV;
1124 goto ini_nomem;
1125 }
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001126
Matt Wilsond0b4d642013-01-15 13:21:27 +00001127 nr_init_grefs = nr_grant_frames * grefs_per_grant_frame;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001128
1129 for (i = NR_RESERVED_ENTRIES; i < nr_init_grefs - 1; i++)
1130 gnttab_entry(i) = i + 1;
1131
1132 gnttab_entry(nr_init_grefs - 1) = GNTTAB_LIST_END;
1133 gnttab_free_count = nr_init_grefs - NR_RESERVED_ENTRIES;
1134 gnttab_free_head = NR_RESERVED_ENTRIES;
1135
1136 printk("Grant table initialized\n");
1137 return 0;
1138
1139 ini_nomem:
1140 for (i--; i >= 0; i--)
1141 free_page((unsigned long)gnttab_list[i]);
1142 kfree(gnttab_list);
Julia Lawall6b5e7d92012-04-15 11:27:12 +02001143 return ret;
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001144}
Stefano Stabellini183d03c2010-05-17 17:08:21 +01001145EXPORT_SYMBOL_GPL(gnttab_init);
Jeremy Fitzhardingead9a8612007-07-17 18:37:06 -07001146
Greg Kroah-Hartman345a5252012-12-21 13:00:00 -08001147static int __gnttab_init(void)
Stefano Stabellini183d03c2010-05-17 17:08:21 +01001148{
1149 /* Delay grant-table initialization in the PV on HVM case */
1150 if (xen_hvm_domain())
1151 return 0;
1152
1153 if (!xen_pv_domain())
1154 return -ENODEV;
1155
1156 return gnttab_init();
1157}
Konrad Rzeszutek Wilk6926f6d2014-01-03 10:20:18 -05001158/* Starts after core_initcall so that xen_pvh_gnttab_setup can be called
1159 * beforehand to initialize xen_auto_xlat_grant_frames. */
1160core_initcall_sync(__gnttab_init);