x86/public: Split the struct cpu_user_regs type

In order to support FRED, we're going to have to remove the {ds..gs} fields
from struct cpu_user_regs, meaning that it is going to have to become a
different type to the structure embedded in vcpu_guest_context_u.

struct cpu_user_regs is a name used in common Xen code (i.e. needs to stay
using this name), so renaming the public struct to be guest_user_regs in Xen's
view only.

Introduce a brand hew cpu-user-regs.h, currently containing a duplicate
structure.  This removes the need for current.h to include public/xen.h, and
highlights a case where the emulator was picking up cpu_user_regs
transitively.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
CC: Jan Beulich <JBeulich@suse.com>
CC: Roger Pau Monné <roger.pau@citrix.com>
Jan: Is this what you intended?

cpu_user_regs_t and the guest handle don't seem to be used anywhere.  I'm
tempted to exclude them from Xen builds.

diff --git a/xen/arch/x86/include/asm/cpu-user-regs.h b/xen/arch/x86/include/asm/cpu-user-regs.h
new file mode 100644 (file)
index 0000000..845b41a
--- /dev/null
+++ b/xen/arch/x86/include/asm/cpu-user-regs.h
@@ -0,0 +1,69 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef X86_CPU_USER_REGS_H
+#define X86_CPU_USER_REGS_H
+
+#define DECL_REG_LOHI(which) union { \
+    uint64_t r ## which ## x; \
+    uint32_t e ## which ## x; \
+    uint16_t which ## x; \
+    struct { \
+        uint8_t which ## l; \
+        uint8_t which ## h; \
+    }; \
+}
+#define DECL_REG_LO8(name) union { \
+    uint64_t r ## name; \
+    uint32_t e ## name; \
+    uint16_t name; \
+    uint8_t name ## l; \
+}
+#define DECL_REG_LO16(name) union { \
+    uint64_t r ## name; \
+    uint32_t e ## name; \
+    uint16_t name; \
+}
+#define DECL_REG_HI(num) union { \
+    uint64_t r ## num; \
+    uint32_t r ## num ## d; \
+    uint16_t r ## num ## w; \
+    uint8_t r ## num ## b; \
+}
+
+struct cpu_user_regs
+{
+    DECL_REG_HI(15);
+    DECL_REG_HI(14);
+    DECL_REG_HI(13);
+    DECL_REG_HI(12);
+    DECL_REG_LO8(bp);
+    DECL_REG_LOHI(b);
+    DECL_REG_HI(11);
+    DECL_REG_HI(10);
+    DECL_REG_HI(9);
+    DECL_REG_HI(8);
+    DECL_REG_LOHI(a);
+    DECL_REG_LOHI(c);
+    DECL_REG_LOHI(d);
+    DECL_REG_LO8(si);
+    DECL_REG_LO8(di);
+    uint32_t error_code;
+    uint32_t entry_vector;
+    DECL_REG_LO16(ip);
+    uint16_t cs, _pad0[1];
+    uint8_t  saved_upcall_mask;
+    uint8_t  _pad1[3];
+    DECL_REG_LO16(flags); /* rflags.IF == !saved_upcall_mask */
+    DECL_REG_LO8(sp);
+    uint16_t ss, _pad2[3];
+    uint16_t es, _pad3[3];
+    uint16_t ds, _pad4[3];
+    uint16_t fs, _pad5[3];
+    uint16_t gs, _pad6[3];
+};
+
+#undef DECL_REG_HI
+#undef DECL_REG_LO16
+#undef DECL_REG_LO8
+#undef DECL_REG_LOHI
+
+#endif /* X86_CPU_USER_REGS_H */

diff --git a/xen/arch/x86/include/asm/current.h b/xen/arch/x86/include/asm/current.h
index bcec328c9875145d45d1d763a7bd371a564eb441..243d17ef79fd23c022b3078acc908f2cb96a71d6 100644 (file)
--- a/xen/arch/x86/include/asm/current.h
+++ b/xen/arch/x86/include/asm/current.h
@@ -9,7 +9,8 @@
 
 #include <xen/percpu.h>
 #include <xen/page-size.h>
-#include <public/xen.h>
+
+#include <asm/cpu-user-regs.h>
 
 /*
  * Xen's cpu stacks are 8 pages (8-page aligned), arranged as:

diff --git a/xen/arch/x86/x86_emulate/private.h b/xen/arch/x86/x86_emulate/private.h
index ef4745f56e27d1e7caf75c124a32908fdd152051..dde4d3e3ccef5b913e29874b0d4d837ccb8f3d21 100644 (file)
--- a/xen/arch/x86/x86_emulate/private.h
+++ b/xen/arch/x86/x86_emulate/private.h
@@ -10,6 +10,8 @@
 
 # include <xen/bug.h>
 # include <xen/kernel.h>
+
+# include <asm/cpu-user-regs.h>
 # include <asm/endbr.h>
 # include <asm/msr-index.h>
 # include <asm/x86-vendors.h>

diff --git a/xen/include/public/arch-x86/xen-x86_32.h b/xen/include/public/arch-x86/xen-x86_32.h
index 9e3bf06b121e73622e6547f638e0eaafb236a713..cd21438ab12bc0c7b12cf6620393b0035176eeaf 100644 (file)
--- a/xen/include/public/arch-x86/xen-x86_32.h
+++ b/xen/include/public/arch-x86/xen-x86_32.h
@@ -114,6 +114,10 @@
 #define __DECL_REG_LO16(name) uint32_t e ## name
 #endif
 
+#ifdef __XEN__
+#define cpu_user_regs guest_user_regs
+#endif
+
 struct cpu_user_regs {
     __DECL_REG_LO8(b);
     __DECL_REG_LO8(c);
@@ -139,6 +143,10 @@ struct cpu_user_regs {
 typedef struct cpu_user_regs cpu_user_regs_t;
 DEFINE_XEN_GUEST_HANDLE(cpu_user_regs_t);
 
+#ifdef __XEN__
+#undef cpu_user_regs
+#endif
+
 #undef __DECL_REG_LO8
 #undef __DECL_REG_LO16
 

diff --git a/xen/include/public/arch-x86/xen-x86_64.h b/xen/include/public/arch-x86/xen-x86_64.h
index 43f6e3d22001fe3335ef61a478e19ef47e27d1cc..4388e20eaf49e11dc6d765d64e3c995e250d41c4 100644 (file)
--- a/xen/include/public/arch-x86/xen-x86_64.h
+++ b/xen/include/public/arch-x86/xen-x86_64.h
@@ -159,6 +159,10 @@ struct iret_context {
 #define __DECL_REG_HI(num)    uint64_t r ## num
 #endif
 
+#ifdef __XEN__
+#define cpu_user_regs guest_user_regs
+#endif
+
 struct cpu_user_regs {
     __DECL_REG_HI(15);
     __DECL_REG_HI(14);
@@ -192,6 +196,10 @@ struct cpu_user_regs {
 typedef struct cpu_user_regs cpu_user_regs_t;
 DEFINE_XEN_GUEST_HANDLE(cpu_user_regs_t);
 
+#ifdef __XEN__
+#undef cpu_user_regs
+#endif
+
 #undef __DECL_REG
 #undef __DECL_REG_LOHI
 #undef __DECL_REG_LO8

diff --git a/xen/include/public/arch-x86/xen.h b/xen/include/public/arch-x86/xen.h
index fc2487986642a7694578ab9d2f5f16d09761bff8..3b0fd05432f498c5b9042e799d8a200a56193c84 100644 (file)
--- a/xen/include/public/arch-x86/xen.h
+++ b/xen/include/public/arch-x86/xen.h
@@ -173,7 +173,13 @@ struct vcpu_guest_context {
 #define _VGCF_online                   5
 #define VGCF_online                    (1<<_VGCF_online)
     unsigned long flags;                    /* VGCF_* flags                 */
+
+#ifdef __XEN__
+    struct guest_user_regs user_regs;       /* User-level CPU registers     */
+#else
     struct cpu_user_regs user_regs;         /* User-level CPU registers     */
+#endif
+
     struct trap_info trap_ctxt[256];        /* Virtual IDT                  */
     unsigned long ldt_base, ldt_ents;       /* LDT (linear address, # ents) */
     unsigned long gdt_frames[16], gdt_ents; /* GDT (machine frames, # ents) */