8956 Implement KPTI
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>

@@ -1,10 +1,10 @@
 /*
  * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
  */
 /*
- * Copyright 2016 Joyent, Inc.
+ * Copyright 2018 Joyent, Inc.
  */
 
 #ifndef _SYS_SEGMENTS_H
 #define _SYS_SEGMENTS_H
 

@@ -96,33 +96,34 @@
  * with a DPL below user (ring 3) the int $n will generate a #gp fault
  * which the hypervisor catches and forwards to the guest.
  */
 #if defined(__xpv)
 
-#if defined(__amd64)
-
 #define SEL_XPL         0               /* hypervisor privilege level */
 #define SEL_KPL         3               /* both kernel and user in ring 3 */
 #define TRP_KPL         1               /* system gate priv (user blocked) */
-
-#elif defined(__i386)
-
-#define SEL_XPL         0               /* hypervisor privilege level */
-#define SEL_KPL         1               /* kernel privilege level */
-#define TRP_KPL         SEL_KPL         /* system gate priv (user blocked) */
-
-#endif  /* __i386 */
-
 #define TRP_XPL         0               /* system gate priv (hypervisor) */
 
+#define IST_DBG         0
+
 #else   /* __xpv */
 
 #define SEL_KPL         0               /* kernel privilege level on metal */
 #define TRP_KPL         SEL_KPL         /* system gate priv (user blocked) */
 
+
+#define IST_DF          1
+#define IST_NMI         2
+#define IST_MCE         3
+#define IST_DBG         4
+#define IST_NESTABLE    5
+#define IST_DEFAULT     6
+
 #endif  /* __xpv */
 
+#define IST_NONE        0
+
 #define SEL_UPL         3               /* user priority level */
 #define TRP_UPL         3               /* system gate priv (user allowed) */
 #define SEL_TI_LDT      4               /* local descriptor table */
 #define SEL_LDT(s)      (IDXTOSEL(s) | SEL_TI_LDT | SEL_UPL)    /* local sel */
 #define CPL_MASK        3               /* RPL mask for selector */

@@ -399,10 +400,12 @@
 extern void set_usegd(user_desc_t *, void *, size_t, uint_t, uint_t,
     uint_t, uint_t);
 
 #endif  /* __i386 */
 
+extern uint_t idt_vector_to_ist(uint_t);
+
 extern void set_gatesegd(gate_desc_t *, void (*)(void), selector_t,
     uint_t, uint_t, uint_t);
 
 extern void set_syssegd(system_desc_t *, void *, size_t, uint_t, uint_t);
 

@@ -644,10 +647,14 @@
 #define LDT_ALTSIGCALL  5       /* EOL me, alternate call gate for sigreturn */
 #define LDT_UDBASE      6       /* user descriptor base index */
 #define MINNLDT         512     /* Current min solaris ldt size (1 4K page) */
 #define MAXNLDT         8192    /* max solaris ldt size (16 4K pages) */
 
+#ifdef _KERNEL
+#define LDT_CPU_SIZE    (16 * 4096)     /* Size of kernel per-CPU allocation */
+#endif
+
 #ifndef _ASM
 
 extern  gate_desc_t     *idt0;
 extern  desctbr_t       idt0_default_reg;
 extern  user_desc_t     *gdt0;

@@ -684,14 +691,31 @@
 extern void achktrap(), mcetrap();
 extern void xmtrap();
 extern void fasttrap();
 extern void dtrace_ret();
 
+/* KPTI trampolines */
+extern void tr_invaltrap();
+extern void tr_div0trap(), tr_dbgtrap(), tr_nmiint(), tr_brktrap();
+extern void tr_ovflotrap(), tr_boundstrap(), tr_invoptrap(), tr_ndptrap();
+#if !defined(__xpv)
+extern void tr_syserrtrap();
+#endif
+extern void tr_invaltrap(), tr_invtsstrap(), tr_segnptrap(), tr_stktrap();
+extern void tr_gptrap(), tr_pftrap(), tr_ndperr();
+extern void tr_overrun(), tr_resvtrap();
+extern void tr_achktrap(), tr_mcetrap();
+extern void tr_xmtrap();
+extern void tr_fasttrap();
+extern void tr_dtrace_ret();
+
 #if !defined(__amd64)
 extern void pentium_pftrap();
 #endif
 
+extern uint64_t kpti_enable;
+
 #endif /* _ASM */
 
 #ifdef  __cplusplus
 }
 #endif