/******************************************************************************
* grant_table.h
*
* Two sets of functionality:
* 1. Granting foreign access to our memory reservation.
* 2. Accessing others' memory reservations via grant references.
* (i.e., mechanisms for both sender and recipient of grant references)
*
* Copyright (c) 2004-2005, K A Fraser
* Copyright (c) 2005, Christopher Clark
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation; or, when distributed
* separately from the Linux kernel or incorporated into other
* software packages, subject to the following license:
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this source file (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#ifndef __ASM_GNTTAB_H__
#define __ASM_GNTTAB_H__
#include <asm/page.h>
#include <xen/interface/xen.h>
#include <xen/interface/grant_table.h>
#include <asm/xen/hypervisor.h>
#include <xen/features.h>
#define GNTTAB_RESERVED_XENSTORE 1
/* NR_GRANT_FRAMES must be less than or equal to that configured in Xen */
#define NR_GRANT_FRAMES 4
struct gnttab_free_callback {
struct gnttab_free_callback *next;
void (*fn)(void *);
void *arg;
u16 count;
};
int gnttab_init(void);
int gnttab_suspend(void);
int gnttab_resume(void);
int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
int readonly);
int gnttab_grant_foreign_access_subpage(domid_t domid, unsigned long frame,
int flags, unsigned page_off,
unsigned length);
int gnttab_grant_foreign_access_trans(domid_t domid, int flags,
domid_t trans_domid,
grant_ref_t trans_gref);
/*
* Are sub-page grants available on this version of Xen? Returns true if they
* are, and false if they're not.
*/
bool gnttab_subpage_grants_available(void);
/*
* Are transitive grants available on this version of Xen? Returns true if they
* are, and false if they're not.
*/
bool gnttab_trans_grants_available(void);
/*
* End access through the given grant reference, iff the grant entry is no
* longer in use. Return 1 if the grant entry was freed, 0 if it is still in
* use.
*/
int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly);
/*
* Eventually end access through the given grant reference, and once that
* access has been ended, free the given page too. Access will be ended
* immediately iff the grant entry is not in use, otherwise it will happen
* some time later. page may be 0, in which case no freeing will occur.
*/
void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
unsigned long page);
int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn);
unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);
int gnttab_query_foreign_access(grant_ref_t ref);
/*
* operations on reserved batches of grant references
*/
int gnttab_alloc_grant_references(u16 count, grant_ref_t *pprivate_head);
void gnttab_free_grant_reference(grant_ref_t ref);
void gnttab_free_grant_references(grant_ref_t head);
int gnttab_empty_grant_references(const grant_ref_t *pprivate_head);
int gnttab_claim_grant_reference(grant_ref_t *pprivate_head);
void gnttab_release_grant_reference(grant_ref_t *private_head,
grant_ref_t release);
void gnttab_request_free_callback(struct gnttab_free_callback *callback,
void (*fn)(void *), void *arg, u16 count);
void gnttab_cancel_free_callback(struct gnttab_free_callback *callback);
void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
unsigned long frame, int readonly);
int gnttab_grant_foreign_access_subpage_ref(grant_ref_t ref, domid_t domid,
unsigned long frame, int flags,
unsigned page_off,
unsigned length);
int gnttab_grant_foreign_access_trans_ref(grant_ref_t ref, domid_t domid,
int flags, domid_t trans_domid,
grant_ref_t trans_gref);
void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
unsigned long pfn);
static inline void
gnttab_set_map_op(struct gnttab_map_grant_ref *map, phys_addr_t addr,
uint32_t flags, grant_ref_t ref, domid_t domid)
{
if (flags & GNTMAP_contains_pte)
map->host_addr = addr;
else if (xen_feature(XENFEAT_auto_translated_physmap))
map->host_addr = __pa(addr);
else
map->host_addr = addr;
map->flags = flags;
map->ref = ref;
map->dom = domid;
}
static inline void
gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, phys_addr_t addr,
uint32_t flags, grant_handle_t handle)
{
if (flags & GNTMAP_contains_pte)
unmap->host_addr = addr;
else if (xen_feature(XENFEAT_auto_translated_physmap))
unmap->host_addr = __pa(addr);
else
unmap->host_addr = addr;
unmap->handle = handle;
unmap->dev_bus_addr = 0;
}
int arch_gnttab_map_shared(xen_pfn_t *frames, unsigned long nr_gframes,
unsigned long max_nr_gframes,
void **__shared);
int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
unsigned long max_nr_gframes,
grant_status_t **__shared);
void arch_gnttab_unmap(void *shared, unsigned long nr_gframes);
extern unsigned long xen_hvm_resume_frames;
unsigned int gnttab_max_grant_frames(void);
#define gnttab_map_vaddr(map) ((void *)(map.host_virt_addr))
int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count);
int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
struct gnttab_map_grant_ref *kunmap_ops,
struct page **pages, unsigned int count);
/* Perform a batch of grant map/copy operations. Retry every batch slot
* for which the hypervisor returns GNTST_eagain. This is typically due
* to paged out target frames.
*
* Will retry for 1, 2, ... 255 ms, i.e. 256 times during 32 seconds.
*
* Return value in each iand every status field of the batch guaranteed
* to not be GNTST_eagain.
*/
void gnttab_batch_map(struct gnttab_map_grant_ref *batch, unsigned count);
void gnttab_batch_copy(struct gnttab_copy *batch, unsigned count);
#endif /* __ASM_GNTTAB_H__ */
