linux/linux-5.4.31/arch/s390/include/asm/uv.h

133 lines
2.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Ultravisor Interfaces
*
* Copyright IBM Corp. 2019
*
* Author(s):
* Vasily Gorbik <gor@linux.ibm.com>
* Janosch Frank <frankja@linux.ibm.com>
*/
#ifndef _ASM_S390_UV_H
#define _ASM_S390_UV_H
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/bug.h>
#include <asm/page.h>
#define UVC_RC_EXECUTED 0x0001
#define UVC_RC_INV_CMD 0x0002
#define UVC_RC_INV_STATE 0x0003
#define UVC_RC_INV_LEN 0x0005
#define UVC_RC_NO_RESUME 0x0007
#define UVC_CMD_QUI 0x0001
#define UVC_CMD_SET_SHARED_ACCESS 0x1000
#define UVC_CMD_REMOVE_SHARED_ACCESS 0x1001
/* Bits in installed uv calls */
enum uv_cmds_inst {
BIT_UVC_CMD_QUI = 0,
BIT_UVC_CMD_SET_SHARED_ACCESS = 8,
BIT_UVC_CMD_REMOVE_SHARED_ACCESS = 9,
};
struct uv_cb_header {
u16 len;
u16 cmd; /* Command Code */
u16 rc; /* Response Code */
u16 rrc; /* Return Reason Code */
} __packed __aligned(8);
struct uv_cb_qui {
struct uv_cb_header header;
u64 reserved08;
u64 inst_calls_list[4];
u64 reserved30[15];
} __packed __aligned(8);
struct uv_cb_share {
struct uv_cb_header header;
u64 reserved08[3];
u64 paddr;
u64 reserved28;
} __packed __aligned(8);
static inline int uv_call(unsigned long r1, unsigned long r2)
{
int cc;
asm volatile(
"0: .insn rrf,0xB9A40000,%[r1],%[r2],0,0\n"
" brc 3,0b\n"
" ipm %[cc]\n"
" srl %[cc],28\n"
: [cc] "=d" (cc)
: [r1] "a" (r1), [r2] "a" (r2)
: "memory", "cc");
return cc;
}
#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
extern int prot_virt_guest;
static inline int is_prot_virt_guest(void)
{
return prot_virt_guest;
}
static inline int share(unsigned long addr, u16 cmd)
{
struct uv_cb_share uvcb = {
.header.cmd = cmd,
.header.len = sizeof(uvcb),
.paddr = addr
};
if (!is_prot_virt_guest())
return -ENOTSUPP;
/*
* Sharing is page wise, if we encounter addresses that are
* not page aligned, we assume something went wrong. If
* malloced structs are passed to this function, we could leak
* data to the hypervisor.
*/
BUG_ON(addr & ~PAGE_MASK);
if (!uv_call(0, (u64)&uvcb))
return 0;
return -EINVAL;
}
/*
* Guest 2 request to the Ultravisor to make a page shared with the
* hypervisor for IO.
*
* @addr: Real or absolute address of the page to be shared
*/
static inline int uv_set_shared(unsigned long addr)
{
return share(addr, UVC_CMD_SET_SHARED_ACCESS);
}
/*
* Guest 2 request to the Ultravisor to make a page unshared.
*
* @addr: Real or absolute address of the page to be unshared
*/
static inline int uv_remove_shared(unsigned long addr)
{
return share(addr, UVC_CMD_REMOVE_SHARED_ACCESS);
}
void uv_query_info(void);
#else
#define is_prot_virt_guest() 0
static inline int uv_set_shared(unsigned long addr) { return 0; }
static inline int uv_remove_shared(unsigned long addr) { return 0; }
static inline void uv_query_info(void) {}
#endif
#endif /* _ASM_S390_UV_H */