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v5.14.15
  1/******************************************************************************
  2 * grant_table.h
  3 *
  4 * Two sets of functionality:
  5 * 1. Granting foreign access to our memory reservation.
  6 * 2. Accessing others' memory reservations via grant references.
  7 * (i.e., mechanisms for both sender and recipient of grant references)
  8 *
  9 * Copyright (c) 2004-2005, K A Fraser
 10 * Copyright (c) 2005, Christopher Clark
 11 *
 12 * This program is free software; you can redistribute it and/or
 13 * modify it under the terms of the GNU General Public License version 2
 14 * as published by the Free Software Foundation; or, when distributed
 15 * separately from the Linux kernel or incorporated into other
 16 * software packages, subject to the following license:
 17 *
 18 * Permission is hereby granted, free of charge, to any person obtaining a copy
 19 * of this source file (the "Software"), to deal in the Software without
 20 * restriction, including without limitation the rights to use, copy, modify,
 21 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
 22 * and to permit persons to whom the Software is furnished to do so, subject to
 23 * the following conditions:
 24 *
 25 * The above copyright notice and this permission notice shall be included in
 26 * all copies or substantial portions of the Software.
 27 *
 28 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 29 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 30 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 31 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 32 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 33 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 34 * IN THE SOFTWARE.
 35 */
 36
 37#ifndef __ASM_GNTTAB_H__
 38#define __ASM_GNTTAB_H__
 39
 40#include <asm/page.h>
 41
 42#include <xen/interface/xen.h>
 43#include <xen/interface/grant_table.h>
 44
 45#include <asm/xen/hypervisor.h>
 46
 47#include <xen/features.h>
 48#include <xen/page.h>
 49#include <linux/mm_types.h>
 50#include <linux/page-flags.h>
 51#include <linux/kernel.h>
 52
 53/*
 54 * Technically there's no reliably invalid grant reference or grant handle,
 55 * so pick the value that is the most unlikely one to be observed valid.
 56 */
 57#define INVALID_GRANT_REF          ((grant_ref_t)-1)
 58#define INVALID_GRANT_HANDLE       ((grant_handle_t)-1)
 59
 60#define GNTTAB_RESERVED_XENSTORE 1
 61
 62/* NR_GRANT_FRAMES must be less than or equal to that configured in Xen */
 63#define NR_GRANT_FRAMES 4
 64
 65struct gnttab_free_callback {
 66	struct gnttab_free_callback *next;
 67	void (*fn)(void *);
 68	void *arg;
 69	u16 count;
 70};
 71
 72struct gntab_unmap_queue_data;
 73
 74typedef void (*gnttab_unmap_refs_done)(int result, struct gntab_unmap_queue_data *data);
 75
 76struct gntab_unmap_queue_data
 77{
 78	struct delayed_work	gnttab_work;
 79	void *data;
 80	gnttab_unmap_refs_done	done;
 81	struct gnttab_unmap_grant_ref *unmap_ops;
 82	struct gnttab_unmap_grant_ref *kunmap_ops;
 83	struct page **pages;
 84	unsigned int count;
 85	unsigned int age;
 86};
 87
 88int gnttab_init(void);
 89int gnttab_suspend(void);
 90int gnttab_resume(void);
 91
 92int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
 93				int readonly);
 94
 95/*
 96 * End access through the given grant reference, iff the grant entry is no
 97 * longer in use.  Return 1 if the grant entry was freed, 0 if it is still in
 98 * use.
 99 */
100int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly);
101
102/*
103 * Eventually end access through the given grant reference, and once that
104 * access has been ended, free the given page too.  Access will be ended
105 * immediately iff the grant entry is not in use, otherwise it will happen
106 * some time later.  page may be 0, in which case no freeing will occur.
107 */
108void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
109			       unsigned long page);
110
111int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn);
112
113unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
114unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);
115
116int gnttab_query_foreign_access(grant_ref_t ref);
117
118/*
119 * operations on reserved batches of grant references
120 */
121int gnttab_alloc_grant_references(u16 count, grant_ref_t *pprivate_head);
122
123void gnttab_free_grant_reference(grant_ref_t ref);
124
125void gnttab_free_grant_references(grant_ref_t head);
126
127int gnttab_empty_grant_references(const grant_ref_t *pprivate_head);
128
129int gnttab_claim_grant_reference(grant_ref_t *pprivate_head);
130
131void gnttab_release_grant_reference(grant_ref_t *private_head,
132				    grant_ref_t release);
133
134void gnttab_request_free_callback(struct gnttab_free_callback *callback,
135				  void (*fn)(void *), void *arg, u16 count);
136void gnttab_cancel_free_callback(struct gnttab_free_callback *callback);
137
138void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
139				     unsigned long frame, int readonly);
140
141/* Give access to the first 4K of the page */
142static inline void gnttab_page_grant_foreign_access_ref_one(
143	grant_ref_t ref, domid_t domid,
144	struct page *page, int readonly)
145{
146	gnttab_grant_foreign_access_ref(ref, domid, xen_page_to_gfn(page),
147					readonly);
148}
149
150void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
151				       unsigned long pfn);
152
153static inline void
154gnttab_set_map_op(struct gnttab_map_grant_ref *map, phys_addr_t addr,
155		  uint32_t flags, grant_ref_t ref, domid_t domid)
156{
157	if (flags & GNTMAP_contains_pte)
158		map->host_addr = addr;
159	else if (xen_feature(XENFEAT_auto_translated_physmap))
160		map->host_addr = __pa(addr);
161	else
162		map->host_addr = addr;
163
164	map->flags = flags;
165	map->ref = ref;
166	map->dom = domid;
167	map->status = 1; /* arbitrary positive value */
168}
169
170static inline void
171gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, phys_addr_t addr,
172		    uint32_t flags, grant_handle_t handle)
173{
174	if (flags & GNTMAP_contains_pte)
175		unmap->host_addr = addr;
176	else if (xen_feature(XENFEAT_auto_translated_physmap))
177		unmap->host_addr = __pa(addr);
178	else
179		unmap->host_addr = addr;
180
181	unmap->handle = handle;
182	unmap->dev_bus_addr = 0;
183}
184
185int arch_gnttab_init(unsigned long nr_shared, unsigned long nr_status);
186int arch_gnttab_map_shared(xen_pfn_t *frames, unsigned long nr_gframes,
187			   unsigned long max_nr_gframes,
188			   void **__shared);
189int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
190			   unsigned long max_nr_gframes,
191			   grant_status_t **__shared);
192void arch_gnttab_unmap(void *shared, unsigned long nr_gframes);
193
194struct grant_frames {
195	xen_pfn_t *pfn;
196	unsigned int count;
197	void *vaddr;
198};
199extern struct grant_frames xen_auto_xlat_grant_frames;
200unsigned int gnttab_max_grant_frames(void);
201int gnttab_setup_auto_xlat_frames(phys_addr_t addr);
202void gnttab_free_auto_xlat_frames(void);
203
204#define gnttab_map_vaddr(map) ((void *)(map.host_virt_addr))
205
206int gnttab_alloc_pages(int nr_pages, struct page **pages);
207void gnttab_free_pages(int nr_pages, struct page **pages);
208
209struct gnttab_page_cache {
210	spinlock_t		lock;
211#ifdef CONFIG_XEN_UNPOPULATED_ALLOC
212	struct page		*pages;
213#else
214	struct list_head	pages;
215#endif
216	unsigned int		num_pages;
217};
218
219void gnttab_page_cache_init(struct gnttab_page_cache *cache);
220int gnttab_page_cache_get(struct gnttab_page_cache *cache, struct page **page);
221void gnttab_page_cache_put(struct gnttab_page_cache *cache, struct page **page,
222			   unsigned int num);
223void gnttab_page_cache_shrink(struct gnttab_page_cache *cache,
224			      unsigned int num);
225
226#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
227struct gnttab_dma_alloc_args {
228	/* Device for which DMA memory will be/was allocated. */
229	struct device *dev;
230	/* If set then DMA buffer is coherent and write-combine otherwise. */
231	bool coherent;
232
233	int nr_pages;
234	struct page **pages;
235	xen_pfn_t *frames;
236	void *vaddr;
237	dma_addr_t dev_bus_addr;
238};
239
240int gnttab_dma_alloc_pages(struct gnttab_dma_alloc_args *args);
241int gnttab_dma_free_pages(struct gnttab_dma_alloc_args *args);
242#endif
243
244int gnttab_pages_set_private(int nr_pages, struct page **pages);
245void gnttab_pages_clear_private(int nr_pages, struct page **pages);
246
247int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
248		    struct gnttab_map_grant_ref *kmap_ops,
249		    struct page **pages, unsigned int count);
250int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
251		      struct gnttab_unmap_grant_ref *kunmap_ops,
252		      struct page **pages, unsigned int count);
253void gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item);
254int gnttab_unmap_refs_sync(struct gntab_unmap_queue_data *item);
255
256
257/* Perform a batch of grant map/copy operations. Retry every batch slot
258 * for which the hypervisor returns GNTST_eagain. This is typically due
259 * to paged out target frames.
260 *
261 * Will retry for 1, 2, ... 255 ms, i.e. 256 times during 32 seconds.
262 *
263 * Return value in each iand every status field of the batch guaranteed
264 * to not be GNTST_eagain.
265 */
266void gnttab_batch_map(struct gnttab_map_grant_ref *batch, unsigned count);
267void gnttab_batch_copy(struct gnttab_copy *batch, unsigned count);
268
269
270struct xen_page_foreign {
271	domid_t domid;
272	grant_ref_t gref;
273};
274
275static inline struct xen_page_foreign *xen_page_foreign(struct page *page)
276{
277	if (!PageForeign(page))
278		return NULL;
279#if BITS_PER_LONG < 64
280	return (struct xen_page_foreign *)page->private;
281#else
282	BUILD_BUG_ON(sizeof(struct xen_page_foreign) > BITS_PER_LONG);
283	return (struct xen_page_foreign *)&page->private;
284#endif
285}
286
287/* Split Linux page in chunk of the size of the grant and call fn
288 *
289 * Parameters of fn:
290 *	gfn: guest frame number
291 *	offset: offset in the grant
292 *	len: length of the data in the grant.
293 *	data: internal information
294 */
295typedef void (*xen_grant_fn_t)(unsigned long gfn, unsigned int offset,
296			       unsigned int len, void *data);
297
298void gnttab_foreach_grant_in_range(struct page *page,
299				   unsigned int offset,
300				   unsigned int len,
301				   xen_grant_fn_t fn,
302				   void *data);
303
304/* Helper to get to call fn only on the first "grant chunk" */
305static inline void gnttab_for_one_grant(struct page *page, unsigned int offset,
306					unsigned len, xen_grant_fn_t fn,
307					void *data)
308{
309	/* The first request is limited to the size of one grant */
310	len = min_t(unsigned int, XEN_PAGE_SIZE - (offset & ~XEN_PAGE_MASK),
311		    len);
312
313	gnttab_foreach_grant_in_range(page, offset, len, fn, data);
314}
315
316/* Get @nr_grefs grants from an array of page and call fn for each grant */
317void gnttab_foreach_grant(struct page **pages,
318			  unsigned int nr_grefs,
319			  xen_grant_fn_t fn,
320			  void *data);
321
322/* Get the number of grant in a specified region
323 *
324 * start: Offset from the beginning of the first page
325 * len: total length of data (can cross multiple page)
326 */
327static inline unsigned int gnttab_count_grant(unsigned int start,
328					      unsigned int len)
329{
330	return XEN_PFN_UP(xen_offset_in_page(start) + len);
331}
332
333#endif /* __ASM_GNTTAB_H__ */
v4.6
  1/******************************************************************************
  2 * grant_table.h
  3 *
  4 * Two sets of functionality:
  5 * 1. Granting foreign access to our memory reservation.
  6 * 2. Accessing others' memory reservations via grant references.
  7 * (i.e., mechanisms for both sender and recipient of grant references)
  8 *
  9 * Copyright (c) 2004-2005, K A Fraser
 10 * Copyright (c) 2005, Christopher Clark
 11 *
 12 * This program is free software; you can redistribute it and/or
 13 * modify it under the terms of the GNU General Public License version 2
 14 * as published by the Free Software Foundation; or, when distributed
 15 * separately from the Linux kernel or incorporated into other
 16 * software packages, subject to the following license:
 17 *
 18 * Permission is hereby granted, free of charge, to any person obtaining a copy
 19 * of this source file (the "Software"), to deal in the Software without
 20 * restriction, including without limitation the rights to use, copy, modify,
 21 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
 22 * and to permit persons to whom the Software is furnished to do so, subject to
 23 * the following conditions:
 24 *
 25 * The above copyright notice and this permission notice shall be included in
 26 * all copies or substantial portions of the Software.
 27 *
 28 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 29 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 30 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 31 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 32 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 33 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 34 * IN THE SOFTWARE.
 35 */
 36
 37#ifndef __ASM_GNTTAB_H__
 38#define __ASM_GNTTAB_H__
 39
 40#include <asm/page.h>
 41
 42#include <xen/interface/xen.h>
 43#include <xen/interface/grant_table.h>
 44
 45#include <asm/xen/hypervisor.h>
 46
 47#include <xen/features.h>
 48#include <xen/page.h>
 49#include <linux/mm_types.h>
 50#include <linux/page-flags.h>
 51#include <linux/kernel.h>
 52
 
 
 
 
 
 
 
 53#define GNTTAB_RESERVED_XENSTORE 1
 54
 55/* NR_GRANT_FRAMES must be less than or equal to that configured in Xen */
 56#define NR_GRANT_FRAMES 4
 57
 58struct gnttab_free_callback {
 59	struct gnttab_free_callback *next;
 60	void (*fn)(void *);
 61	void *arg;
 62	u16 count;
 63};
 64
 65struct gntab_unmap_queue_data;
 66
 67typedef void (*gnttab_unmap_refs_done)(int result, struct gntab_unmap_queue_data *data);
 68
 69struct gntab_unmap_queue_data
 70{
 71	struct delayed_work	gnttab_work;
 72	void *data;
 73	gnttab_unmap_refs_done	done;
 74	struct gnttab_unmap_grant_ref *unmap_ops;
 75	struct gnttab_unmap_grant_ref *kunmap_ops;
 76	struct page **pages;
 77	unsigned int count;
 78	unsigned int age;
 79};
 80
 81int gnttab_init(void);
 82int gnttab_suspend(void);
 83int gnttab_resume(void);
 84
 85int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
 86				int readonly);
 87
 88/*
 89 * End access through the given grant reference, iff the grant entry is no
 90 * longer in use.  Return 1 if the grant entry was freed, 0 if it is still in
 91 * use.
 92 */
 93int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly);
 94
 95/*
 96 * Eventually end access through the given grant reference, and once that
 97 * access has been ended, free the given page too.  Access will be ended
 98 * immediately iff the grant entry is not in use, otherwise it will happen
 99 * some time later.  page may be 0, in which case no freeing will occur.
100 */
101void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
102			       unsigned long page);
103
104int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn);
105
106unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
107unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);
108
109int gnttab_query_foreign_access(grant_ref_t ref);
110
111/*
112 * operations on reserved batches of grant references
113 */
114int gnttab_alloc_grant_references(u16 count, grant_ref_t *pprivate_head);
115
116void gnttab_free_grant_reference(grant_ref_t ref);
117
118void gnttab_free_grant_references(grant_ref_t head);
119
120int gnttab_empty_grant_references(const grant_ref_t *pprivate_head);
121
122int gnttab_claim_grant_reference(grant_ref_t *pprivate_head);
123
124void gnttab_release_grant_reference(grant_ref_t *private_head,
125				    grant_ref_t release);
126
127void gnttab_request_free_callback(struct gnttab_free_callback *callback,
128				  void (*fn)(void *), void *arg, u16 count);
129void gnttab_cancel_free_callback(struct gnttab_free_callback *callback);
130
131void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
132				     unsigned long frame, int readonly);
133
134/* Give access to the first 4K of the page */
135static inline void gnttab_page_grant_foreign_access_ref_one(
136	grant_ref_t ref, domid_t domid,
137	struct page *page, int readonly)
138{
139	gnttab_grant_foreign_access_ref(ref, domid, xen_page_to_gfn(page),
140					readonly);
141}
142
143void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
144				       unsigned long pfn);
145
146static inline void
147gnttab_set_map_op(struct gnttab_map_grant_ref *map, phys_addr_t addr,
148		  uint32_t flags, grant_ref_t ref, domid_t domid)
149{
150	if (flags & GNTMAP_contains_pte)
151		map->host_addr = addr;
152	else if (xen_feature(XENFEAT_auto_translated_physmap))
153		map->host_addr = __pa(addr);
154	else
155		map->host_addr = addr;
156
157	map->flags = flags;
158	map->ref = ref;
159	map->dom = domid;
 
160}
161
162static inline void
163gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, phys_addr_t addr,
164		    uint32_t flags, grant_handle_t handle)
165{
166	if (flags & GNTMAP_contains_pte)
167		unmap->host_addr = addr;
168	else if (xen_feature(XENFEAT_auto_translated_physmap))
169		unmap->host_addr = __pa(addr);
170	else
171		unmap->host_addr = addr;
172
173	unmap->handle = handle;
174	unmap->dev_bus_addr = 0;
175}
176
177int arch_gnttab_init(unsigned long nr_shared);
178int arch_gnttab_map_shared(xen_pfn_t *frames, unsigned long nr_gframes,
179			   unsigned long max_nr_gframes,
180			   void **__shared);
 
 
 
181void arch_gnttab_unmap(void *shared, unsigned long nr_gframes);
182
183struct grant_frames {
184	xen_pfn_t *pfn;
185	unsigned int count;
186	void *vaddr;
187};
188extern struct grant_frames xen_auto_xlat_grant_frames;
189unsigned int gnttab_max_grant_frames(void);
190int gnttab_setup_auto_xlat_frames(phys_addr_t addr);
191void gnttab_free_auto_xlat_frames(void);
192
193#define gnttab_map_vaddr(map) ((void *)(map.host_virt_addr))
194
195int gnttab_alloc_pages(int nr_pages, struct page **pages);
196void gnttab_free_pages(int nr_pages, struct page **pages);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
197
198int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
199		    struct gnttab_map_grant_ref *kmap_ops,
200		    struct page **pages, unsigned int count);
201int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
202		      struct gnttab_unmap_grant_ref *kunmap_ops,
203		      struct page **pages, unsigned int count);
204void gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item);
205int gnttab_unmap_refs_sync(struct gntab_unmap_queue_data *item);
206
207
208/* Perform a batch of grant map/copy operations. Retry every batch slot
209 * for which the hypervisor returns GNTST_eagain. This is typically due
210 * to paged out target frames.
211 *
212 * Will retry for 1, 2, ... 255 ms, i.e. 256 times during 32 seconds.
213 *
214 * Return value in each iand every status field of the batch guaranteed
215 * to not be GNTST_eagain.
216 */
217void gnttab_batch_map(struct gnttab_map_grant_ref *batch, unsigned count);
218void gnttab_batch_copy(struct gnttab_copy *batch, unsigned count);
219
220
221struct xen_page_foreign {
222	domid_t domid;
223	grant_ref_t gref;
224};
225
226static inline struct xen_page_foreign *xen_page_foreign(struct page *page)
227{
228	if (!PageForeign(page))
229		return NULL;
230#if BITS_PER_LONG < 64
231	return (struct xen_page_foreign *)page->private;
232#else
233	BUILD_BUG_ON(sizeof(struct xen_page_foreign) > BITS_PER_LONG);
234	return (struct xen_page_foreign *)&page->private;
235#endif
236}
237
238/* Split Linux page in chunk of the size of the grant and call fn
239 *
240 * Parameters of fn:
241 *	gfn: guest frame number
242 *	offset: offset in the grant
243 *	len: length of the data in the grant.
244 *	data: internal information
245 */
246typedef void (*xen_grant_fn_t)(unsigned long gfn, unsigned int offset,
247			       unsigned int len, void *data);
248
249void gnttab_foreach_grant_in_range(struct page *page,
250				   unsigned int offset,
251				   unsigned int len,
252				   xen_grant_fn_t fn,
253				   void *data);
254
255/* Helper to get to call fn only on the first "grant chunk" */
256static inline void gnttab_for_one_grant(struct page *page, unsigned int offset,
257					unsigned len, xen_grant_fn_t fn,
258					void *data)
259{
260	/* The first request is limited to the size of one grant */
261	len = min_t(unsigned int, XEN_PAGE_SIZE - (offset & ~XEN_PAGE_MASK),
262		    len);
263
264	gnttab_foreach_grant_in_range(page, offset, len, fn, data);
265}
266
267/* Get @nr_grefs grants from an array of page and call fn for each grant */
268void gnttab_foreach_grant(struct page **pages,
269			  unsigned int nr_grefs,
270			  xen_grant_fn_t fn,
271			  void *data);
272
273/* Get the number of grant in a specified region
274 *
275 * start: Offset from the beginning of the first page
276 * len: total length of data (can cross multiple page)
277 */
278static inline unsigned int gnttab_count_grant(unsigned int start,
279					      unsigned int len)
280{
281	return XEN_PFN_UP(xen_offset_in_page(start) + len);
282}
283
284#endif /* __ASM_GNTTAB_H__ */