diff options
| -rw-r--r-- | arch/s390/Kconfig | 11 | ||||
| -rw-r--r-- | arch/s390/boot/Makefile | 1 | ||||
| -rw-r--r-- | arch/s390/boot/startup.c | 2 | ||||
| -rw-r--r-- | arch/s390/boot/uv.c | 24 | ||||
| -rw-r--r-- | arch/s390/include/asm/uv.h | 132 | ||||
| -rw-r--r-- | arch/s390/kernel/setup.c | 5 |
6 files changed, 175 insertions, 0 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index b6e3d0653002..4ac8d49e206a 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -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" diff --git a/arch/s390/boot/Makefile b/arch/s390/boot/Makefile index 458d18c44c67..a5ae68b2aa84 100644 --- a/arch/s390/boot/Makefile +++ b/arch/s390/boot/Makefile @@ -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 diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c index 57d7f9446e29..2bd4a62d436c 100644 --- a/arch/s390/boot/startup.c +++ b/arch/s390/boot/startup.c @@ -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(); diff --git a/arch/s390/boot/uv.c b/arch/s390/boot/uv.c new file mode 100644 index 000000000000..ed007f4a6444 --- /dev/null +++ b/arch/s390/boot/uv.c @@ -0,0 +1,24 @@ +// 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; +} diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h new file mode 100644 index 000000000000..ef3c00b049ab --- /dev/null +++ b/arch/s390/include/asm/uv.h @@ -0,0 +1,132 @@ +/* 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 */ diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index 2c642af526ce..70197a68e6fa 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -70,6 +70,7 @@ #include <asm/alternative.h> #include <asm/nospec-branch.h> #include <asm/mem_detect.h> +#include <asm/uv.h> #include "entry.h" /* @@ -89,6 +90,10 @@ char elf_platform[ELF_PLATFORM_SIZE]; unsigned long int_hwcap = 0; +#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST +int __bootdata_preserved(prot_virt_guest); +#endif + int __bootdata(noexec_disabled); int __bootdata(memory_end_set); unsigned long __bootdata(memory_end); |