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|
/******************************************************************************
* hypercall.h
*
* Linux-specific hypervisor handling.
*
* Copyright (c) 2002-2004, K A Fraser
*
* 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_X86_XEN_HYPERCALL_H
#define _ASM_X86_XEN_HYPERCALL_H
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/pgtable.h>
#include <trace/events/xen.h>
#include <asm/page.h>
#include <asm/smap.h>
#include <asm/nospec-branch.h>
#include <xen/interface/xen.h>
#include <xen/interface/sched.h>
#include <xen/interface/physdev.h>
#include <xen/interface/platform.h>
#include <xen/interface/xen-mca.h>
struct xen_dm_op_buf;
/*
* The hypercall asms have to meet several constraints:
* - Work on 32- and 64-bit.
* The two architectures put their arguments in different sets of
* registers.
*
* - Work around asm syntax quirks
* It isn't possible to specify one of the rNN registers in a
* constraint, so we use explicit register variables to get the
* args into the right place.
*
* - Mark all registers as potentially clobbered
* Even unused parameters can be clobbered by the hypervisor, so we
* need to make sure gcc knows it.
*
* - Avoid compiler bugs.
* This is the tricky part. Because x86_32 has such a constrained
* register set, gcc versions below 4.3 have trouble generating
* code when all the arg registers and memory are trashed by the
* asm. There are syntactically simpler ways of achieving the
* semantics below, but they cause the compiler to crash.
*
* The only combination I found which works is:
* - assign the __argX variables first
* - list all actually used parameters as "+r" (__argX)
* - clobber the rest
*
* The result certainly isn't pretty, and it really shows up cpp's
* weakness as a macro language. Sorry. (But let's just give thanks
* there aren't more than 5 arguments...)
*/
extern struct { char _entry[32]; } hypercall_page[];
#define __HYPERCALL "call hypercall_page+%c[offset]"
#define __HYPERCALL_ENTRY(x) \
[offset] "i" (__HYPERVISOR_##x * sizeof(hypercall_page[0]))
#ifdef CONFIG_X86_32
#define __HYPERCALL_RETREG "eax"
#define __HYPERCALL_ARG1REG "ebx"
#define __HYPERCALL_ARG2REG "ecx"
#define __HYPERCALL_ARG3REG "edx"
#define __HYPERCALL_ARG4REG "esi"
#define __HYPERCALL_ARG5REG "edi"
#else
#define __HYPERCALL_RETREG "rax"
#define __HYPERCALL_ARG1REG "rdi"
#define __HYPERCALL_ARG2REG "rsi"
#define __HYPERCALL_ARG3REG "rdx"
#define __HYPERCALL_ARG4REG "r10"
#define __HYPERCALL_ARG5REG "r8"
#endif
#define __HYPERCALL_DECLS \
register unsigned long __res asm(__HYPERCALL_RETREG); \
register unsigned long __arg1 asm(__HYPERCALL_ARG1REG) = __arg1; \
register unsigned long __arg2 asm(__HYPERCALL_ARG2REG) = __arg2; \
register unsigned long __arg3 asm(__HYPERCALL_ARG3REG) = __arg3; \
register unsigned long __arg4 asm(__HYPERCALL_ARG4REG) = __arg4; \
register unsigned long __arg5 asm(__HYPERCALL_ARG5REG) = __arg5;
#define __HYPERCALL_0PARAM "=r" (__res), ASM_CALL_CONSTRAINT
#define __HYPERCALL_1PARAM __HYPERCALL_0PARAM, "+r" (__arg1)
#define __HYPERCALL_2PARAM __HYPERCALL_1PARAM, "+r" (__arg2)
#define __HYPERCALL_3PARAM __HYPERCALL_2PARAM, "+r" (__arg3)
#define __HYPERCALL_4PARAM __HYPERCALL_3PARAM, "+r" (__arg4)
#define __HYPERCALL_5PARAM __HYPERCALL_4PARAM, "+r" (__arg5)
#define __HYPERCALL_0ARG()
#define __HYPERCALL_1ARG(a1) \
__HYPERCALL_0ARG() __arg1 = (unsigned long)(a1);
#define __HYPERCALL_2ARG(a1,a2) \
__HYPERCALL_1ARG(a1) __arg2 = (unsigned long)(a2);
#define __HYPERCALL_3ARG(a1,a2,a3) \
__HYPERCALL_2ARG(a1,a2) __arg3 = (unsigned long)(a3);
#define __HYPERCALL_4ARG(a1,a2,a3,a4) \
__HYPERCALL_3ARG(a1,a2,a3) __arg4 = (unsigned long)(a4);
#define __HYPERCALL_5ARG(a1,a2,a3,a4,a5) \
__HYPERCALL_4ARG(a1,a2,a3,a4) __arg5 = (unsigned long)(a5);
#define __HYPERCALL_CLOBBER5 "memory"
#define __HYPERCALL_CLOBBER4 __HYPERCALL_CLOBBER5, __HYPERCALL_ARG5REG
#define __HYPERCALL_CLOBBER3 __HYPERCALL_CLOBBER4, __HYPERCALL_ARG4REG
#define __HYPERCALL_CLOBBER2 __HYPERCALL_CLOBBER3, __HYPERCALL_ARG3REG
#define __HYPERCALL_CLOBBER1 __HYPERCALL_CLOBBER2, __HYPERCALL_ARG2REG
#define __HYPERCALL_CLOBBER0 __HYPERCALL_CLOBBER1, __HYPERCALL_ARG1REG
#define _hypercall0(type, name) \
({ \
__HYPERCALL_DECLS; \
__HYPERCALL_0ARG(); \
asm volatile (__HYPERCALL \
: __HYPERCALL_0PARAM \
: __HYPERCALL_ENTRY(name) \
: __HYPERCALL_CLOBBER0); \
(type)__res; \
})
#define _hypercall1(type, name, a1) \
({ \
__HYPERCALL_DECLS; \
__HYPERCALL_1ARG(a1); \
asm volatile (__HYPERCALL \
: __HYPERCALL_1PARAM \
: __HYPERCALL_ENTRY(name) \
: __HYPERCALL_CLOBBER1); \
(type)__res; \
})
#define _hypercall2(type, name, a1, a2) \
({ \
__HYPERCALL_DECLS; \
__HYPERCALL_2ARG(a1, a2); \
asm volatile (__HYPERCALL \
: __HYPERCALL_2PARAM \
: __HYPERCALL_ENTRY(name) \
: __HYPERCALL_CLOBBER2); \
(type)__res; \
})
#define _hypercall3(type, name, a1, a2, a3) \
({ \
__HYPERCALL_DECLS; \
__HYPERCALL_3ARG(a1, a2, a3); \
asm volatile (__HYPERCALL \
: __HYPERCALL_3PARAM \
: __HYPERCALL_ENTRY(name) \
: __HYPERCALL_CLOBBER3); \
(type)__res; \
})
#define _hypercall4(type, name, a1, a2, a3, a4) \
({ \
__HYPERCALL_DECLS; \
__HYPERCALL_4ARG(a1, a2, a3, a4); \
asm volatile (__HYPERCALL \
: __HYPERCALL_4PARAM \
: __HYPERCALL_ENTRY(name) \
: __HYPERCALL_CLOBBER4); \
(type)__res; \
})
static inline long
xen_single_call(unsigned int call,
unsigned long a1, unsigned long a2,
unsigned long a3, unsigned long a4,
unsigned long a5)
{
__HYPERCALL_DECLS;
__HYPERCALL_5ARG(a1, a2, a3, a4, a5);
if (call >= PAGE_SIZE / sizeof(hypercall_page[0]))
return -EINVAL;
asm volatile(CALL_NOSPEC
: __HYPERCALL_5PARAM
: [thunk_target] "a" (&hypercall_page[call])
: __HYPERCALL_CLOBBER5);
return (long)__res;
}
static __always_inline void __xen_stac(void)
{
/*
* Suppress objtool seeing the STAC/CLAC and getting confused about it
* calling random code with AC=1.
*/
asm volatile(ANNOTATE_IGNORE_ALTERNATIVE
ASM_STAC ::: "memory", "flags");
}
static __always_inline void __xen_clac(void)
{
asm volatile(ANNOTATE_IGNORE_ALTERNATIVE
ASM_CLAC ::: "memory", "flags");
}
static inline long
privcmd_call(unsigned int call,
unsigned long a1, unsigned long a2,
unsigned long a3, unsigned long a4,
unsigned long a5)
{
long res;
__xen_stac();
res = xen_single_call(call, a1, a2, a3, a4, a5);
__xen_clac();
return res;
}
static inline int
HYPERVISOR_set_trap_table(struct trap_info *table)
{
return _hypercall1(int, set_trap_table, table);
}
static inline int
HYPERVISOR_mmu_update(struct mmu_update *req, int count,
int *success_count, domid_t domid)
{
return _hypercall4(int, mmu_update, req, count, success_count, domid);
}
static inline int
HYPERVISOR_mmuext_op(struct mmuext_op *op, int count,
int *success_count, domid_t domid)
{
return _hypercall4(int, mmuext_op, op, count, success_count, domid);
}
static inline int
HYPERVISOR_set_gdt(unsigned long *frame_list, int entries)
{
return _hypercall2(int, set_gdt, frame_list, entries);
}
static inline int
HYPERVISOR_callback_op(int cmd, void *arg)
{
return _hypercall2(int, callback_op, cmd, arg);
}
static inline int
HYPERVISOR_sched_op(int cmd, void *arg)
{
return _hypercall2(int, sched_op, cmd, arg);
}
static inline long
HYPERVISOR_set_timer_op(u64 timeout)
{
unsigned long timeout_hi = (unsigned long)(timeout>>32);
unsigned long timeout_lo = (unsigned long)timeout;
return _hypercall2(long, set_timer_op, timeout_lo, timeout_hi);
}
static inline int
HYPERVISOR_mca(struct xen_mc *mc_op)
{
mc_op->interface_version = XEN_MCA_INTERFACE_VERSION;
return _hypercall1(int, mca, mc_op);
}
static inline int
HYPERVISOR_platform_op(struct xen_platform_op *op)
{
op->interface_version = XENPF_INTERFACE_VERSION;
return _hypercall1(int, platform_op, op);
}
static inline int
HYPERVISOR_set_debugreg(int reg, unsigned long value)
{
return _hypercall2(int, set_debugreg, reg, value);
}
static inline unsigned long
HYPERVISOR_get_debugreg(int reg)
{
return _hypercall1(unsigned long, get_debugreg, reg);
}
static inline int
HYPERVISOR_update_descriptor(u64 ma, u64 desc)
{
if (sizeof(u64) == sizeof(long))
return _hypercall2(int, update_descriptor, ma, desc);
return _hypercall4(int, update_descriptor, ma, ma>>32, desc, desc>>32);
}
static inline long
HYPERVISOR_memory_op(unsigned int cmd, void *arg)
{
return _hypercall2(long, memory_op, cmd, arg);
}
static inline int
HYPERVISOR_multicall(void *call_list, uint32_t nr_calls)
{
return _hypercall2(int, multicall, call_list, nr_calls);
}
static inline int
HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val,
unsigned long flags)
{
if (sizeof(new_val) == sizeof(long))
return _hypercall3(int, update_va_mapping, va,
new_val.pte, flags);
else
return _hypercall4(int
|