[deliverable/linux.git] / include / asm-x86 / lguest_hcall.h

/* Architecture specific portion of the lguest hypercalls */
#ifndef _X86_LGUEST_HCALL_H
#define _X86_LGUEST_HCALL_H

#include <asm/hw_irq.h>

#define LHCALL_FLUSH_ASYNC	0
#define LHCALL_LGUEST_INIT	1
#define LHCALL_CRASH		2
#define LHCALL_LOAD_GDT		3
#define LHCALL_NEW_PGTABLE	4
#define LHCALL_FLUSH_TLB	5
#define LHCALL_LOAD_IDT_ENTRY	6
#define LHCALL_SET_STACK	7
#define LHCALL_TS		8
#define LHCALL_SET_CLOCKEVENT	9
#define LHCALL_HALT		10
#define LHCALL_BIND_DMA		12
#define LHCALL_SEND_DMA		13
#define LHCALL_SET_PTE		14
#define LHCALL_SET_PMD		15
#define LHCALL_LOAD_TLS		16

/*G:031 First, how does our Guest contact the Host to ask for privileged
 * operations?  There are two ways: the direct way is to make a "hypercall",
 * to make requests of the Host Itself.
 *
 * Our hypercall mechanism uses the highest unused trap code (traps 32 and
 * above are used by real hardware interrupts).  Seventeen hypercalls are
 * available: the hypercall number is put in the %eax register, and the
 * arguments (when required) are placed in %edx, %ebx and %ecx.  If a return
 * value makes sense, it's returned in %eax.
 *
 * Grossly invalid calls result in Sudden Death at the hands of the vengeful
 * Host, rather than returning failure.  This reflects Winston Churchill's
 * definition of a gentleman: "someone who is only rude intentionally". */
#define LGUEST_TRAP_ENTRY 0x1F

static inline unsigned long
hcall(unsigned long call,
      unsigned long arg1, unsigned long arg2, unsigned long arg3)
{
	/* "int" is the Intel instruction to trigger a trap. */
	asm volatile("int $" __stringify(LGUEST_TRAP_ENTRY)
		       /* The call is in %eax (aka "a"), and can be replaced */
		     : "=a"(call)
		       /* The other arguments are in %eax, %edx, %ebx & %ecx */
		     : "a"(call), "d"(arg1), "b"(arg2), "c"(arg3)
		       /* "memory" means this might write somewhere in memory.
			* This isn't true for all calls, but it's safe to tell
			* gcc that it might happen so it doesn't get clever. */
		     : "memory");
	return call;
}
/*:*/

void async_hcall(unsigned long call,
		 unsigned long arg1, unsigned long arg2, unsigned long arg3);

/* Can't use our min() macro here: needs to be a constant */
#define LGUEST_IRQS (NR_IRQS < 32 ? NR_IRQS: 32)

#define LHCALL_RING_SIZE 64
struct hcall_args
{
	/* These map directly onto eax, ebx, ecx, edx in struct lguest_regs */
	unsigned long arg0, arg2, arg3, arg1;
};
#endif	/* _I386_LGUEST_HCALL_H */
Commit	Line	Data
c37ae93d JS	1	/* Architecture specific portion of the lguest hypercalls */
	2	#ifndef _X86_LGUEST_HCALL_H
	3	#define _X86_LGUEST_HCALL_H
	4
b410e7b1 JS	5	#include <asm/hw_irq.h>
b410e7b1 JS	6
c37ae93d JS	7	#define LHCALL_FLUSH_ASYNC 0
	8	#define LHCALL_LGUEST_INIT 1
	9	#define LHCALL_CRASH 2
	10	#define LHCALL_LOAD_GDT 3
	11	#define LHCALL_NEW_PGTABLE 4
	12	#define LHCALL_FLUSH_TLB 5
	13	#define LHCALL_LOAD_IDT_ENTRY 6
	14	#define LHCALL_SET_STACK 7
	15	#define LHCALL_TS 8
	16	#define LHCALL_SET_CLOCKEVENT 9
	17	#define LHCALL_HALT 10
	18	#define LHCALL_BIND_DMA 12
	19	#define LHCALL_SEND_DMA 13
	20	#define LHCALL_SET_PTE 14
	21	#define LHCALL_SET_PMD 15
	22	#define LHCALL_LOAD_TLS 16
	23
	24	/*G:031 First, how does our Guest contact the Host to ask for privileged
	25	* operations? There are two ways: the direct way is to make a "hypercall",
	26	* to make requests of the Host Itself.
	27	*
	28	* Our hypercall mechanism uses the highest unused trap code (traps 32 and
	29	* above are used by real hardware interrupts). Seventeen hypercalls are
	30	* available: the hypercall number is put in the %eax register, and the
	31	* arguments (when required) are placed in %edx, %ebx and %ecx. If a return
	32	* value makes sense, it's returned in %eax.
	33	*
	34	* Grossly invalid calls result in Sudden Death at the hands of the vengeful
	35	* Host, rather than returning failure. This reflects Winston Churchill's
	36	* definition of a gentleman: "someone who is only rude intentionally". */
	37	#define LGUEST_TRAP_ENTRY 0x1F
	38
	39	static inline unsigned long
	40	hcall(unsigned long call,
	41	unsigned long arg1, unsigned long arg2, unsigned long arg3)
	42	{
	43	/* "int" is the Intel instruction to trigger a trap. */
	44	asm volatile("int $" __stringify(LGUEST_TRAP_ENTRY)
	45	/* The call is in %eax (aka "a"), and can be replaced */
	46	: "=a"(call)
	47	/* The other arguments are in %eax, %edx, %ebx & %ecx */
	48	: "a"(call), "d"(arg1), "b"(arg2), "c"(arg3)
	49	/* "memory" means this might write somewhere in memory.
	50	* This isn't true for all calls, but it's safe to tell
	51	* gcc that it might happen so it doesn't get clever. */
	52	: "memory");
	53	return call;
	54	}
	55	/:/
	56
	57	void async_hcall(unsigned long call,
	58	unsigned long arg1, unsigned long arg2, unsigned long arg3);
	59
	60	/* Can't use our min() macro here: needs to be a constant */
	61	#define LGUEST_IRQS (NR_IRQS < 32 ? NR_IRQS: 32)
	62
	63	#define LHCALL_RING_SIZE 64
b410e7b1	64	struct hcall_args
c37ae93d	65	{
b410e7b1 JS	66	/* These map directly onto eax, ebx, ecx, edx in struct lguest_regs */
b410e7b1 JS	67	unsigned long arg0, arg2, arg3, arg1;
c37ae93d	68	};
c37ae93d	69	#endif /* _I386_LGUEST_HCALL_H */