x86: Merge struct msr_policy into struct cpu_policy

As with the cpuid side, use a temporary define to make struct msr_policy still
work.

Note, this means that domains now have two separate struct cpu_policy
allocations with disjoint information, and system policies are in a similar
position, as well as xc_cpu_policy objects in libxenguest.  All of these
duplications will be addressed in the following patches.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 03812da375)

tools/fuzz/cpu-policy/afl-policy-fuzzer.c

@@ -10,7 +10,6 @@
 
 #include <xen-tools/libs.h>
 #include <xen/lib/x86/cpu-policy.h>
-#include <xen/lib/x86/msr.h>
 #include <xen/domctl.h>
 
 static bool debug;

xen/include/asm-x86/msr.h

@@ -6,8 +6,9 @@
 #include <xen/types.h>
 #include <xen/percpu.h>
 #include <xen/errno.h>
+#include <xen/kernel.h>
 
-#include <xen/lib/x86/msr.h>
+#include <xen/lib/x86/cpu-policy.h>
 
 #include <asm/asm_defns.h>
 #include <asm/cpufeature.h>

xen/include/xen/lib/x86/cpu-policy.h

@@ -3,7 +3,6 @@
 #define XEN_LIB_X86_POLICIES_H
 
 #include <xen/lib/x86/cpuid-autogen.h>
-#include <xen/lib/x86/msr.h>
 
 #define FEATURESET_1d     0 /* 0x00000001.edx      */
 #define FEATURESET_1c     1 /* 0x00000001.ecx      */
@@ -107,6 +106,9 @@ const char *x86_cpuid_vendor_to_str(unsigned int vendor);
      CPUID_GUEST_NR_XSTATE - !!CPUID_GUEST_NR_XSTATE +  \
      CPUID_GUEST_NR_EXTD + 2 /* hv_limit and hv2_limit */ )
 
+/* Maximum number of MSRs written when serialising a cpu_policy. */
+#define MSR_MAX_SERIALISED_ENTRIES 2
+
 struct cpu_policy
 {
 #define DECL_BITFIELD(word) _DECL_BITFIELD(FEATURESET_ ## word)
@@ -324,6 +326,44 @@ struct cpu_policy
         };
     } extd;
 
+    /*
+     * 0x000000ce - MSR_INTEL_PLATFORM_INFO
+     *
+     * This MSR is non-architectural, but for simplicy we allow it to be read
+     * unconditionally.  CPUID Faulting support can be fully emulated for HVM
+     * guests so can be offered unconditionally, while support for PV guests
+     * is dependent on real hardware support.
+     */
+    union {
+        uint32_t raw;
+        struct {
+            uint32_t :31;
+            bool cpuid_faulting:1;
+        };
+    } platform_info;
+
+    /*
+     * 0x0000010a - MSR_ARCH_CAPABILITIES
+     *
+     * This is an Intel-only MSR, which provides miscellaneous enumeration,
+     * including those which indicate that microarchitectrual sidechannels are
+     * fixed in hardware.
+     */
+    union {
+        uint32_t raw;
+        struct {
+            bool rdcl_no:1;
+            bool ibrs_all:1;
+            bool rsba:1;
+            bool skip_l1dfl:1;
+            bool ssb_no:1;
+            bool mds_no:1;
+            bool if_pschange_mc_no:1;
+            bool tsx_ctrl:1;
+            bool taa_no:1;
+        };
+    } arch_caps;
+
 #undef __DECL_BITFIELD
 #undef _DECL_BITFIELD
 #undef DECL_BITFIELD
@@ -337,6 +377,7 @@ struct cpu_policy
 
 /* Temporary */
 #define cpuid_policy cpu_policy
+#define msr_policy cpu_policy
 
 struct old_cpu_policy
 {
@@ -438,9 +479,11 @@ void x86_cpuid_policy_clear_out_of_range_leaves(struct cpuid_policy *p);
 #ifdef __XEN__
 #include <public/arch-x86/xen.h>
 typedef XEN_GUEST_HANDLE_64(xen_cpuid_leaf_t) cpuid_leaf_buffer_t;
+typedef XEN_GUEST_HANDLE_64(xen_msr_entry_t) msr_entry_buffer_t;
 #else
 #include <xen/arch-x86/xen.h>
 typedef xen_cpuid_leaf_t cpuid_leaf_buffer_t[];
+typedef xen_msr_entry_t msr_entry_buffer_t[];
 #endif
 
 /**
@@ -480,6 +523,42 @@ int x86_cpuid_copy_from_buffer(struct cpuid_policy *policy,
                                uint32_t nr_entries, uint32_t *err_leaf,
                                uint32_t *err_subleaf);
 
+/**
+ * Serialise an msr_policy object into an array.
+ *
+ * @param policy     The msr_policy to serialise.
+ * @param msrs       The array of msrs to serialise into.
+ * @param nr_entries The number of entries in 'msrs'.
+ * @returns -errno
+ *
+ * Writes at most MSR_MAX_SERIALISED_ENTRIES.  May fail with -ENOBUFS if the
+ * buffer array is too short.  On success, nr_entries is updated with the
+ * actual number of msrs written.
+ */
+int x86_msr_copy_to_buffer(const struct msr_policy *policy,
+                           msr_entry_buffer_t msrs, uint32_t *nr_entries);
+
+/**
+ * Unserialise an msr_policy object from an array of msrs.
+ *
+ * @param policy     The msr_policy object to unserialise into.
+ * @param msrs       The array of msrs to unserialise from.
+ * @param nr_entries The number of entries in 'msrs'.
+ * @param err_msr    Optional hint for error diagnostics.
+ * @returns -errno
+ *
+ * Reads at most MSR_MAX_SERIALISED_ENTRIES.  May fail for a number of reasons
+ * based on the content in an individual 'msrs' entry, including the MSR index
+ * not being valid in the policy, the flags field being nonzero, or if the
+ * value provided would truncate when stored in the policy.  In such cases,
+ * the optional err_* pointer will identify the problematic MSR.
+ *
+ * No content validation is performed on the data stored in the policy object.
+ */
+int x86_msr_copy_from_buffer(struct msr_policy *policy,
+                             const msr_entry_buffer_t msrs, uint32_t nr_entries,
+                             uint32_t *err_msr);
+
 /*
  * Calculate whether two policies are compatible.
  *

xen/include/xen/lib/x86/msr.h

@@ -1,104 +0,0 @@
-/* Common data structures and functions consumed by hypervisor and toolstack */
-#ifndef XEN_LIB_X86_MSR_H
-#define XEN_LIB_X86_MSR_H
-
-/* Maximum number of MSRs written when serialising msr_policy. */
-#define MSR_MAX_SERIALISED_ENTRIES 2
-
-/* MSR policy object for shared per-domain MSRs */
-struct msr_policy
-{
-    /*
-     * 0x000000ce - MSR_INTEL_PLATFORM_INFO
-     *
-     * This MSR is non-architectural, but for simplicy we allow it to be read
-     * unconditionally.  CPUID Faulting support can be fully emulated for HVM
-     * guests so can be offered unconditionally, while support for PV guests
-     * is dependent on real hardware support.
-     */
-    union {
-        uint32_t raw;
-        struct {
-            uint32_t :31;
-            bool cpuid_faulting:1;
-        };
-    } platform_info;
-
-    /*
-     * 0x0000010a - MSR_ARCH_CAPABILITIES
-     *
-     * This is an Intel-only MSR, which provides miscellaneous enumeration,
-     * including those which indicate that microarchitectrual sidechannels are
-     * fixed in hardware.
-     */
-    union {
-        uint32_t raw;
-        struct {
-            bool rdcl_no:1;
-            bool ibrs_all:1;
-            bool rsba:1;
-            bool skip_l1dfl:1;
-            bool ssb_no:1;
-            bool mds_no:1;
-            bool if_pschange_mc_no:1;
-            bool tsx_ctrl:1;
-            bool taa_no:1;
-        };
-    } arch_caps;
-};
-
-#ifdef __XEN__
-#include <public/arch-x86/xen.h>
-typedef XEN_GUEST_HANDLE_64(xen_msr_entry_t) msr_entry_buffer_t;
-#else
-#include <xen/arch-x86/xen.h>
-typedef xen_msr_entry_t msr_entry_buffer_t[];
-#endif
-
-/**
- * Serialise an msr_policy object into an array.
- *
- * @param policy     The msr_policy to serialise.
- * @param msrs       The array of msrs to serialise into.
- * @param nr_entries The number of entries in 'msrs'.
- * @returns -errno
- *
- * Writes at most MSR_MAX_SERIALISED_ENTRIES.  May fail with -ENOBUFS if the
- * buffer array is too short.  On success, nr_entries is updated with the
- * actual number of msrs written.
- */
-int x86_msr_copy_to_buffer(const struct msr_policy *policy,
-                           msr_entry_buffer_t msrs, uint32_t *nr_entries);
-
-/**
- * Unserialise an msr_policy object from an array of msrs.
- *
- * @param policy     The msr_policy object to unserialise into.
- * @param msrs       The array of msrs to unserialise from.
- * @param nr_entries The number of entries in 'msrs'.
- * @param err_msr    Optional hint for error diagnostics.
- * @returns -errno
- *
- * Reads at most MSR_MAX_SERIALISED_ENTRIES.  May fail for a number of reasons
- * based on the content in an individual 'msrs' entry, including the MSR index
- * not being valid in the policy, the flags field being nonzero, or if the
- * value provided would truncate when stored in the policy.  In such cases,
- * the optional err_* pointer will identify the problematic MSR.
- *
- * No content validation is performed on the data stored in the policy object.
- */
-int x86_msr_copy_from_buffer(struct msr_policy *policy,
-                             const msr_entry_buffer_t msrs, uint32_t nr_entries,
-                             uint32_t *err_msr);
-
-#endif /* !XEN_LIB_X86_MSR_H */
-
-/*
- * Local variables:
- * mode: C
- * c-file-style: "BSD"
- * c-basic-offset: 4
- * tab-width: 4
- * indent-tabs-mode: nil
- * End:
- */

xen/lib/x86/msr.c

@@ -1,6 +1,6 @@
 #include "private.h"
 
-#include <xen/lib/x86/msr.h>
+#include <xen/lib/x86/cpu-policy.h>
 
 /*
  * Copy a single MSR into the provided msr_entry_buffer_t buffer, performing a