s390/protvirt: introduce host side setup

Add "prot_virt" command line option which controls if the kernel
protected VMs support is enabled at early boot time. This has to be
done early, because it needs large amounts of memory and will disable
some features like STP time sync for the lpar.

Extend ultravisor info definitions and expose it via uv_info struct
filled in during startup.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index dbc22d68462751d2bb59ab35784c1c61c84bbb0a..b0beae9b9e367216fbdbdfeb3da70ce85aa9a91f 100644 (file)
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3795,6 +3795,11 @@
                        before loading.
                        See Documentation/admin-guide/blockdev/ramdisk.rst.
 
+       prot_virt=      [S390] enable hosting protected virtual machines
+                       isolated from the hypervisor (if hardware supports
+                       that).
+                       Format: <bool>
+
        psi=            [KNL] Enable or disable pressure stall information
                        tracking.
                        Format: <bool>

diff --git a/arch/s390/boot/Makefile b/arch/s390/boot/Makefile
index e2c47d3a1c891b7bf5bb783f156ca902c69f1fdf..30f1811540c5e7820d2497ab9e6cf5fffc94f06d 100644 (file)
--- a/arch/s390/boot/Makefile
+++ b/arch/s390/boot/Makefile
@@ -37,7 +37,7 @@ CFLAGS_sclp_early_core.o += -I$(srctree)/drivers/s390/char
 obj-y  := head.o als.o startup.o mem_detect.o ipl_parm.o ipl_report.o
 obj-y  += string.o ebcdic.o sclp_early_core.o mem.o ipl_vmparm.o cmdline.o
 obj-y  += version.o pgm_check_info.o ctype.o text_dma.o
-obj-$(CONFIG_PROTECTED_VIRTUALIZATION_GUEST)   += uv.o
+obj-$(findstring y, $(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) $(CONFIG_PGSTE))  += uv.o
 obj-$(CONFIG_RELOCATABLE)      += machine_kexec_reloc.o
 obj-$(CONFIG_RANDOMIZE_BASE)   += kaslr.o
 targets        := bzImage startup.a section_cmp.boot.data section_cmp.boot.preserved.data $(obj-y)

diff --git a/arch/s390/boot/uv.c b/arch/s390/boot/uv.c
index 3f501159ee9fc2ac1200219337859a03bb02c99f..8fde561f1d07e3e905446c8f9b25d38f79f0b7b8 100644 (file)
--- a/arch/s390/boot/uv.c
+++ b/arch/s390/boot/uv.c
@@ -3,7 +3,13 @@
 #include <asm/facility.h>
 #include <asm/sections.h>
 
+/* will be used in arch/s390/kernel/uv.c */
+#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
 int __bootdata_preserved(prot_virt_guest);
+#endif
+#if IS_ENABLED(CONFIG_KVM)
+struct uv_info __bootdata_preserved(uv_info);
+#endif
 
 void uv_query_info(void)
 {
@@ -19,7 +25,21 @@ void uv_query_info(void)
        if (uv_call(0, (uint64_t)&uvcb) && uvcb.header.rc != 0x100)
                return;
 
+       if (IS_ENABLED(CONFIG_KVM)) {
+               memcpy(uv_info.inst_calls_list, uvcb.inst_calls_list, sizeof(uv_info.inst_calls_list));
+               uv_info.uv_base_stor_len = uvcb.uv_base_stor_len;
+               uv_info.guest_base_stor_len = uvcb.conf_base_phys_stor_len;
+               uv_info.guest_virt_base_stor_len = uvcb.conf_base_virt_stor_len;
+               uv_info.guest_virt_var_stor_len = uvcb.conf_virt_var_stor_len;
+               uv_info.guest_cpu_stor_len = uvcb.cpu_stor_len;
+               uv_info.max_sec_stor_addr = ALIGN(uvcb.max_guest_stor_addr, PAGE_SIZE);
+               uv_info.max_num_sec_conf = uvcb.max_num_sec_conf;
+               uv_info.max_guest_cpus = uvcb.max_guest_cpus;
+       }
+
+#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
        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;
+#endif
 }

diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h
index 4093a2856929a0a420b82c819116fc6d4da6e90b..c6a330740e5d610786159fc8278b9deebeb58aef 100644 (file)
--- a/arch/s390/include/asm/uv.h
+++ b/arch/s390/include/asm/uv.h
@@ -44,7 +44,19 @@ struct uv_cb_qui {
        struct uv_cb_header header;
        u64 reserved08;
        u64 inst_calls_list[4];
-       u64 reserved30[15];
+       u64 reserved30[2];
+       u64 uv_base_stor_len;
+       u64 reserved48;
+       u64 conf_base_phys_stor_len;
+       u64 conf_base_virt_stor_len;
+       u64 conf_virt_var_stor_len;
+       u64 cpu_stor_len;
+       u32 reserved70[3];
+       u32 max_num_sec_conf;
+       u64 max_guest_stor_addr;
+       u8  reserved88[158 - 136];
+       u16 max_guest_cpus;
+       u8  reserveda0[200 - 160];
 } __packed __aligned(8);
 
 struct uv_cb_share {
@@ -69,6 +81,20 @@ static inline int uv_call(unsigned long r1, unsigned long r2)
        return cc;
 }
 
+struct uv_info {
+       unsigned long inst_calls_list[4];
+       unsigned long uv_base_stor_len;
+       unsigned long guest_base_stor_len;
+       unsigned long guest_virt_base_stor_len;
+       unsigned long guest_virt_var_stor_len;
+       unsigned long guest_cpu_stor_len;
+       unsigned long max_sec_stor_addr;
+       unsigned int max_num_sec_conf;
+       unsigned short max_guest_cpus;
+};
+
+extern struct uv_info uv_info;
+
 #ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
 extern int prot_virt_guest;
 
@@ -121,11 +147,26 @@ 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; }
+#endif
+
+#if IS_ENABLED(CONFIG_KVM)
+extern int prot_virt_host;
+
+static inline int is_prot_virt_host(void)
+{
+       return prot_virt_host;
+}
+#else
+#define is_prot_virt_host() 0
+#endif
+
+#if defined(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) || IS_ENABLED(CONFIG_KVM)
+void uv_query_info(void);
+#else
 static inline void uv_query_info(void) {}
 #endif
 

diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
index 2b1203cf7be65880ebde434c16b658c70b559bd3..22bfb8d5084e9cd01fb92630f3397a95d150e069 100644 (file)
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile
@@ -78,6 +78,7 @@ obj-$(CONFIG_PERF_EVENTS)     += perf_cpum_cf_events.o perf_regs.o
 obj-$(CONFIG_PERF_EVENTS)      += perf_cpum_cf_diag.o
 
 obj-$(CONFIG_TRACEPOINTS)      += trace.o
+obj-$(findstring y, $(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) $(CONFIG_PGSTE))  += uv.o
 
 # vdso
 obj-y                          += vdso64/

diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index b2c2f75860e8874623aeab013374cc198f71a57c..a2496382175eafe20e5d5fbba6da274a1c1446d1 100644 (file)
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -92,10 +92,6 @@ 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);

diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c
new file mode 100644 (file)
index 0000000..b1f9367
--- /dev/null
+++ b/arch/s390/kernel/uv.c
@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Common Ultravisor functions and initialization
+ *
+ * Copyright IBM Corp. 2019, 2020
+ */
+#define KMSG_COMPONENT "prot_virt"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/sizes.h>
+#include <linux/bitmap.h>
+#include <linux/memblock.h>
+#include <asm/facility.h>
+#include <asm/sections.h>
+#include <asm/uv.h>
+
+/* the bootdata_preserved fields come from ones in arch/s390/boot/uv.c */
+#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
+int __bootdata_preserved(prot_virt_guest);
+#endif
+
+#if IS_ENABLED(CONFIG_KVM)
+int prot_virt_host;
+EXPORT_SYMBOL(prot_virt_host);
+struct uv_info __bootdata_preserved(uv_info);
+EXPORT_SYMBOL(uv_info);
+
+static int __init prot_virt_setup(char *val)
+{
+       bool enabled;
+       int rc;
+
+       rc = kstrtobool(val, &enabled);
+       if (!rc && enabled)
+               prot_virt_host = 1;
+
+       if (is_prot_virt_guest() && prot_virt_host) {
+               prot_virt_host = 0;
+               pr_warn("Protected virtualization not available in protected guests.");
+       }
+
+       if (prot_virt_host && !test_facility(158)) {
+               prot_virt_host = 0;
+               pr_warn("Protected virtualization not supported by the hardware.");
+       }
+
+       return rc;
+}
+early_param("prot_virt", prot_virt_setup);
+#endif