linux-stable/include/xen/grant_table.h
Stefano Stabellini 2fc136eecd xen/m2p: do not reuse kmap_op->dev_bus_addr
If the caller passes a valid kmap_op to m2p_add_override, we use
kmap_op->dev_bus_addr to store the original mfn, but dev_bus_addr is
part of the interface with Xen and if we are batching the hypercalls it
might not have been written by the hypervisor yet. That means that later
on Xen will write to it and we'll think that the original mfn is
actually what Xen has written to it.

Rather than "stealing" struct members from kmap_op, keep using
page->index to store the original mfn and add another parameter to
m2p_remove_override to get the corresponding kmap_op instead.
It is now responsibility of the caller to keep track of which kmap_op
corresponds to a particular page in the m2p_override (gntdev, the only
user of this interface that passes a valid kmap_op, is already doing that).

CC: stable@kernel.org
Reported-and-Tested-By: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-09-12 11:21:40 -04:00

193 lines
6.5 KiB
C

/******************************************************************************
* 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(unsigned long *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);
#endif /* __ASM_GNTTAB_H__ */