s390/uv: introduce guest side ultravisor code (5abb9351) · Commits · 戴 / test

arch/s390/Kconfig

+11 −0

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		@@ -837,6 +837,17 @@ config HAVE_PNETID

		menu "Virtualization"

		config PROTECTED_VIRTUALIZATION_GUEST
		def_bool n
		prompt "Protected virtualization guest support"
		help
		Select this option, if you want to be able to run this
		kernel as a protected virtualization KVM guest.
		Protected virtualization capable machines have a mini hypervisor
		located at machine level (an ultravisor). With help of the
		Ultravisor, KVM will be able to run "protected" VMs, special
		VMs whose memory and management data are unavailable to KVM.

		config PFAULT
		def_bool y
		prompt "Pseudo page fault support"

arch/s390/boot/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -30,6 +30,7 @@ CFLAGS_sclp_early_core.o += -I$(srctree)/drivers/s390/char

		obj-y := head.o als.o startup.o mem_detect.o ipl_parm.o string.o ebcdic.o
		obj-y += sclp_early_core.o mem.o ipl_vmparm.o cmdline.o ctype.o
		obj-$(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) += uv.o
		targets := bzImage startup.a section_cmp.boot.data section_cmp.boot.preserved.data $(obj-y)
		subdir- := compressed

arch/s390/boot/startup.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -2,6 +2,7 @@
		#include <linux/string.h>
		#include <asm/setup.h>
		#include <asm/sclp.h>
		#include <asm/uv.h>
		#include "compressed/decompressor.h"
		#include "boot.h"

		@@ -53,6 +54,7 @@ void startup_kernel(void)
		{
		void *img;

		uv_query_info();
		rescue_initrd();
		sclp_early_read_info();
		store_ipl_parmblock();

arch/s390/boot/uv.c

0 → 100644

+24 −0

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0
		#include <asm/uv.h>
		#include <asm/facility.h>
		#include <asm/sections.h>

		int __bootdata_preserved(prot_virt_guest);

		void uv_query_info(void)
		{
		struct uv_cb_qui uvcb = {
		.header.cmd = UVC_CMD_QUI,
		.header.len = sizeof(uvcb)
		};

		if (!test_facility(158))
		return;

		if (uv_call(0, (uint64_t)&uvcb))
		return;

		if (test_bit_inv(BIT_UVC_CMD_SET_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list) &&
		test_bit_inv(BIT_UVC_CMD_REMOVE_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list))
		prot_virt_guest = 1;
		}

arch/s390/include/asm/uv.h

0 → 100644

+132 −0

Original line number	Diff line number	Diff line
		/* 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 */

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