[PATCH 04/24] PVH xen: add params to read_segment_register

[Mukesh Rathor <mukesh.rathor@oracle.com>]

In this preparatory patch, read_segment_register macro is changed to take
vcpu and regs parameters. No functionality change.

Changes in V2:  None
Changes in V3:
   - Replace read_sreg with read_segment_register

Changes in V7:
   - Don't make emulate_privileged_op() public here.

Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>
---
 xen/arch/x86/domain.c        |    8 ++++----
 xen/arch/x86/traps.c         |   26 ++++++++++++--------------
 xen/arch/x86/x86_64/traps.c  |   16 ++++++++--------
 xen/include/asm-x86/system.h |    2 +-
 4 files changed, 25 insertions(+), 27 deletions(-)

diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index 73ddad7..5de5e49 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -1221,10 +1221,10 @@ static void save_segments(struct vcpu *v)
     struct cpu_user_regs *regs = &v->arch.user_regs;
     unsigned int dirty_segment_mask = 0;
 
-    regs->ds = read_segment_register(ds);
-    regs->es = read_segment_register(es);
-    regs->fs = read_segment_register(fs);
-    regs->gs = read_segment_register(gs);
+    regs->ds = read_segment_register(v, regs, ds);
+    regs->es = read_segment_register(v, regs, es);
+    regs->fs = read_segment_register(v, regs, fs);
+    regs->gs = read_segment_register(v, regs, gs);
 
     if ( regs->ds )
         dirty_segment_mask |= DIRTY_DS;
diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c
index 57dbd0c..378ef0a 100644
--- a/xen/arch/x86/traps.c
+++ b/xen/arch/x86/traps.c
@@ -1831,8 +1831,6 @@ static inline uint64_t guest_misc_enable(uint64_t val)
     }                                                                       \
     (eip) += sizeof(_x); _x; })
 
-#define read_sreg(regs, sr) read_segment_register(sr)
-
 static int is_cpufreq_controller(struct domain *d)
 {
     return ((cpufreq_controller == FREQCTL_dom0_kernel) &&
@@ -1877,7 +1875,7 @@ static int emulate_privileged_op(struct cpu_user_regs *regs)
         goto fail;
 
     /* emulating only opcodes not allowing SS to be default */
-    data_sel = read_sreg(regs, ds);
+    data_sel = read_segment_register(v, regs, ds);
 
     /* Legacy prefixes. */
     for ( i = 0; i < 8; i++, rex == opcode || (rex = 0) )
@@ -1895,17 +1893,17 @@ static int emulate_privileged_op(struct cpu_user_regs *regs)
             data_sel = regs->cs;
             continue;
         case 0x3e: /* DS override */
-            data_sel = read_sreg(regs, ds);
+            data_sel = read_segment_register(v, regs, ds);
             continue;
         case 0x26: /* ES override */
-            data_sel = read_sreg(regs, es);
+            data_sel = read_segment_register(v, regs, es);
             continue;
         case 0x64: /* FS override */
-            data_sel = read_sreg(regs, fs);
+            data_sel = read_segment_register(v, regs, fs);
             lm_ovr = lm_seg_fs;
             continue;
         case 0x65: /* GS override */
-            data_sel = read_sreg(regs, gs);
+            data_sel = read_segment_register(v, regs, gs);
             lm_ovr = lm_seg_gs;
             continue;
         case 0x36: /* SS override */
@@ -1952,7 +1950,7 @@ static int emulate_privileged_op(struct cpu_user_regs *regs)
 
         if ( !(opcode & 2) )
         {
-            data_sel = read_sreg(regs, es);
+            data_sel = read_segment_register(v, regs, es);
             lm_ovr = lm_seg_none;
         }
 
@@ -2685,22 +2683,22 @@ static void emulate_gate_op(struct cpu_user_regs *regs)
             ASSERT(opnd_sel);
             continue;
         case 0x3e: /* DS override */
-            opnd_sel = read_sreg(regs, ds);
+            opnd_sel = read_segment_register(v, regs, ds);
             if ( !opnd_sel )
                 opnd_sel = dpl;
             continue;
         case 0x26: /* ES override */
-            opnd_sel = read_sreg(regs, es);
+            opnd_sel = read_segment_register(v, regs, es);
             if ( !opnd_sel )
                 opnd_sel = dpl;
             continue;
         case 0x64: /* FS override */
-            opnd_sel = read_sreg(regs, fs);
+            opnd_sel = read_segment_register(v, regs, fs);
             if ( !opnd_sel )
                 opnd_sel = dpl;
             continue;
         case 0x65: /* GS override */
-            opnd_sel = read_sreg(regs, gs);
+            opnd_sel = read_segment_register(v, regs, gs);
             if ( !opnd_sel )
                 opnd_sel = dpl;
             continue;
@@ -2753,7 +2751,7 @@ static void emulate_gate_op(struct cpu_user_regs *regs)
                             switch ( modrm & 7 )
                             {
                             default:
-                                opnd_sel = read_sreg(regs, ds);
+                                opnd_sel = read_segment_register(v, regs, ds);
                                 break;
                             case 4: case 5:
                                 opnd_sel = regs->ss;
@@ -2781,7 +2779,7 @@ static void emulate_gate_op(struct cpu_user_regs *regs)
                             break;
                         }
                         if ( !opnd_sel )
-                            opnd_sel = read_sreg(regs, ds);
+                            opnd_sel = read_segment_register(v, regs, ds);
                         switch ( modrm & 7 )
                         {
                         case 0: case 2: case 4:
diff --git a/xen/arch/x86/x86_64/traps.c b/xen/arch/x86/x86_64/traps.c
index bcd7609..9e0571d 100644
--- a/xen/arch/x86/x86_64/traps.c
+++ b/xen/arch/x86/x86_64/traps.c
@@ -122,10 +122,10 @@ void show_registers(struct cpu_user_regs *regs)
         fault_crs[0] = read_cr0();
         fault_crs[3] = read_cr3();
         fault_crs[4] = read_cr4();
-        fault_regs.ds = read_segment_register(ds);
-        fault_regs.es = read_segment_register(es);
-        fault_regs.fs = read_segment_register(fs);
-        fault_regs.gs = read_segment_register(gs);
+        fault_regs.ds = read_segment_register(v, regs, ds);
+        fault_regs.es = read_segment_register(v, regs, es);
+        fault_regs.fs = read_segment_register(v, regs, fs);
+        fault_regs.gs = read_segment_register(v, regs, gs);
     }
 
     print_xen_info();
@@ -240,10 +240,10 @@ void do_double_fault(struct cpu_user_regs *regs)
     crs[2] = read_cr2();
     crs[3] = read_cr3();
     crs[4] = read_cr4();
-    regs->ds = read_segment_register(ds);
-    regs->es = read_segment_register(es);
-    regs->fs = read_segment_register(fs);
-    regs->gs = read_segment_register(gs);
+    regs->ds = read_segment_register(current, regs, ds);
+    regs->es = read_segment_register(current, regs, es);
+    regs->fs = read_segment_register(current, regs, fs);
+    regs->gs = read_segment_register(current, regs, gs);
 
     printk("CPU:    %d\n", cpu);
     _show_registers(regs, crs, CTXT_hypervisor, NULL);
diff --git a/xen/include/asm-x86/system.h b/xen/include/asm-x86/system.h
index 6ab7d56..9bb22cb 100644
--- a/xen/include/asm-x86/system.h
+++ b/xen/include/asm-x86/system.h
@@ -4,7 +4,7 @@
 #include <xen/lib.h>
 #include <xen/bitops.h>
 
-#define read_segment_register(name)                             \
+#define read_segment_register(vcpu, regs, name)                 \
 ({  u16 __sel;                                                  \
     asm volatile ( "movw %%" STR(name) ",%0" : "=r" (__sel) );  \
     __sel;                                                      \
-- 
1.7.2.3