Move idt.c into lib code

Make it compilable in 32 and 64 bit mode.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

config-x86-common.mak

@@ -11,6 +11,7 @@ cflatobjs += \
 cflatobjs += lib/x86/fwcfg.o
 cflatobjs += lib/x86/apic.o
 cflatobjs += lib/x86/atomic.o
+cflatobjs += lib/x86/idt.o
 
 $(libcflat): LDFLAGS += -nostdlib
 $(libcflat): CFLAGS += -ffreestanding -I lib
@@ -53,7 +54,7 @@ $(TEST_DIR)/vmexit.elf: $(cstart.o) $(TEST_DIR)/vmexit.o
 $(TEST_DIR)/smptest.elf: $(cstart.o) $(TEST_DIR)/smptest.o
 
 $(TEST_DIR)/emulator.elf: $(cstart.o) $(TEST_DIR)/emulator.o \
-			   $(TEST_DIR)/vm.o $(TEST_DIR)/idt.o
+			   $(TEST_DIR)/vm.o
 
 $(TEST_DIR)/port80.elf: $(cstart.o) $(TEST_DIR)/port80.o
 
@@ -68,9 +69,9 @@ $(TEST_DIR)/realmode.o: bits = 32
 
 $(TEST_DIR)/msr.elf: $(cstart.o) $(TEST_DIR)/msr.o
 
-$(TEST_DIR)/idt_test.elf: $(cstart.o) $(TEST_DIR)/idt.o $(TEST_DIR)/idt_test.o
+$(TEST_DIR)/idt_test.elf: $(cstart.o) $(TEST_DIR)/idt_test.o
 
-$(TEST_DIR)/xsave.elf: $(cstart.o) $(TEST_DIR)/idt.o $(TEST_DIR)/xsave.o
+$(TEST_DIR)/xsave.elf: $(cstart.o) $(TEST_DIR)/xsave.o
 
 $(TEST_DIR)/rmap_chain.elf: $(cstart.o) $(TEST_DIR)/rmap_chain.o \
 			     $(TEST_DIR)/vm.o

x86/idt.c → lib/x86/idt.c

 #include "idt.h"
 #include "libcflat.h"
+#include "processor.h"
 
 typedef struct {
     unsigned short offset0;
@@ -11,36 +12,27 @@ typedef struct {
     unsigned short dpl : 2;
     unsigned short p : 1;
     unsigned short offset1;
+#ifdef __x86_64__
     unsigned offset2;
     unsigned reserved;
+#endif
 } idt_entry_t;
 
 static idt_entry_t idt[256];
 
-typedef struct {
-    unsigned short limit;
-    unsigned long linear_addr;
-} __attribute__((packed)) descriptor_table_t;
-
-void lidt(idt_entry_t *idt, int nentries)
+void load_lidt(idt_entry_t *idt, int nentries)
 {
-    descriptor_table_t dt;
+    struct descriptor_table_ptr dt;
 
     dt.limit = nentries * sizeof(*idt) - 1;
-    dt.linear_addr = (unsigned long)idt;
+    dt.base = (unsigned long)idt;
+    lidt(&dt);
     asm volatile ("lidt %0" : : "m"(dt));
 }
 
-unsigned short read_cs()
-{
-    unsigned short r;
-
-    asm volatile ("mov %%cs, %0" : "=r"(r));
-    return r;
-}
-
-void set_idt_entry(idt_entry_t *e, void *addr, int dpl)
+void set_idt_entry(int vec, void *addr, int dpl)
 {
+    idt_entry_t *e = &idt[vec];
     memset(e, 0, sizeof *e);
     e->offset0 = (unsigned long)addr;
     e->selector = read_cs();
@@ -49,14 +41,18 @@ void set_idt_entry(idt_entry_t *e, void *addr, int dpl)
     e->dpl = dpl;
     e->p = 1;
     e->offset1 = (unsigned long)addr >> 16;
+#ifdef __x86_64__
     e->offset2 = (unsigned long)addr >> 32;
+#endif
 }
 
 struct ex_regs {
     unsigned long rax, rcx, rdx, rbx;
     unsigned long dummy, rbp, rsi, rdi;
+#ifdef __x86_64__
     unsigned long r8, r9, r10, r11;
     unsigned long r12, r13, r14, r15;
+#endif
     unsigned long vector;
     unsigned long error_code;
     unsigned long rip;
@@ -90,34 +86,49 @@ void do_handle_exception(struct ex_regs *regs)
     exit(7);
 }
 
+#ifdef __x86_64__
+#  define R "r"
+#  define W "q"
+#  define S "8"
+#else
+#  define R "e"
+#  define W "l"
+#  define S "4"
+#endif
+
 asm (".pushsection .text \n\t"
      "ud_fault: \n\t"
-     "pushq $0 \n\t"
-     "pushq $6 \n\t"
+     "push"W" $0 \n\t"
+     "push"W" $6 \n\t"
      "jmp handle_exception \n\t"
 
      "gp_fault: \n\t"
-     "pushq $13 \n\t"
+     "push"W" $13 \n\t"
      "jmp handle_exception \n\t"
 
      "de_fault: \n\t"
-     "pushq $0 \n\t"
-     "pushq $0 \n\t"
+     "push"W" $0 \n\t"
+     "push"W" $0 \n\t"
      "jmp handle_exception \n\t"
 
      "handle_exception: \n\t"
+#ifdef __x86_64__
      "push %r15; push %r14; push %r13; push %r12 \n\t"
      "push %r11; push %r10; push %r9; push %r8 \n\t"
-     "push %rdi; push %rsi; push %rbp; sub $8, %rsp \n\t"
-     "push %rbx; push %rdx; push %rcx; push %rax \n\t"
-     "mov %rsp, %rdi \n\t"
+#endif
+     "push %"R"di; push %"R"si; push %"R"bp; sub $"S", %"R"sp \n\t"
+     "push %"R"bx; push %"R"dx; push %"R"cx; push %"R"ax \n\t"
+     "mov %"R"sp, %"R"di \n\t"
      "call do_handle_exception \n\t"
-     "pop %rax; pop %rcx; pop %rdx; pop %rbx \n\t"
-     "add $8, %rsp; pop %rbp; pop %rsi; pop %rdi \n\t"
+     "pop %"R"ax; pop %"R"cx; pop %"R"dx; pop %"R"bx \n\t"
+     "add $"S", %"R"sp; pop %"R"bp; pop %"R"si; pop %"R"di \n\t"
+#ifdef __x86_64__
      "pop %r8; pop %r9; pop %r10; pop %r11 \n\t"
      "pop %r12; pop %r13; pop %r14; pop %r15 \n\t"
-     "add $16, %rsp \n\t"
-     "iretq \n\t"
+#endif
+     "add $"S", %"R"sp \n\t"
+     "add $"S", %"R"sp \n\t"
+     "iret"W" \n\t"
      ".popsection");
 
 
@@ -125,10 +136,10 @@ void setup_idt(void)
 {
     extern char ud_fault, gp_fault, de_fault;
 
-    lidt(idt, 256);
-    set_idt_entry(&idt[0], &de_fault, 0);
-    set_idt_entry(&idt[6], &ud_fault, 0);
-    set_idt_entry(&idt[13], &gp_fault, 0);
+    load_lidt(idt, 256);
+    set_idt_entry(0, &de_fault, 0);
+    set_idt_entry(6, &ud_fault, 0);
+    set_idt_entry(13, &gp_fault, 0);
 }
 
 unsigned exception_vector(void)

lib/x86/idt.h

@@ -15,5 +15,6 @@ void setup_idt(void);
 
 unsigned exception_vector(void);
 unsigned exception_error_code(void);
+void set_idt_entry(int vec, void *addr, int dpl);
 
 #endif