s390/protvirt: introduce host side setup

BugLink: https://bugs.launchpad.net/bugs/1835531
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>
(cherry picked from commit ecdc5d842bb3c166c3d549e52ba91a3955b257f2 linux-next)
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 287c3b439c068d65caf8baff97ee42802675e358..8ee3b81cfacd5926c8d2c21836d74c98c2548975 100644 (file)
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3748,6 +3748,11 @@
                        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 0ff9261c915e3fa64369b9e484c3baaed909b6aa..45b33b83de08c7e0458afe43768c4dd102e2e625 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 ef3c00b049ab45b4cd050d97a30e8210b63f7676..e7161ed74a5af2d8930cb97a45abc7dedbc63174 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 d868f94d649b36a02ffb8c71bd9c9a1720601bfb..1efbad27277646aa5d039a2b310fca924db73089 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 dc5df18ec7551d77ecd0d0d9e19ac9fbbdb8d36e..55bff556e67aa60495aca7b4ebe60430bbea7018 100644 (file)
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -93,10 +93,6 @@ 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