From 9d1c6e7c86ddc366d67f0c5fa77be9b93710037a Mon Sep 17 00:00:00 2001 From: Glauber de Oliveira Costa Date: Fri, 19 Oct 2007 20:35:03 +0200 Subject: [PATCH] x86: use descriptor's functions instead of inline assembly This patch provides a new set of functions for managing the descriptor tables that can be used instead of putting the raw assembly in .c files. Remodeling of store_tr() suggested by Frederik Deweerdt. [ tglx: arch/x86 adaptation ] Signed-off-by: Glauber de Oliveira Costa Signed-off-by: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/head64.c | 2 +- arch/x86/kernel/reboot_64.c | 3 ++- arch/x86/kernel/setup64.c | 4 ++-- arch/x86/kernel/suspend_64.c | 11 ++++++----- include/asm-x86/desc_64.h | 30 ++++++++++++++++++++++++++++++ 5 files changed, 41 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index a7eee0a..6b34693 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -58,7 +58,7 @@ void __init x86_64_start_kernel(char * real_mode_data) for (i = 0; i < IDT_ENTRIES; i++) set_intr_gate(i, early_idt_handler); - asm volatile("lidt %0" :: "m" (idt_descr)); + load_idt((const struct desc_ptr *)&idt_descr); early_printk("Kernel alive\n"); diff --git a/arch/x86/kernel/reboot_64.c b/arch/x86/kernel/reboot_64.c index 368db2b..776eb06 100644 --- a/arch/x86/kernel/reboot_64.c +++ b/arch/x86/kernel/reboot_64.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -136,7 +137,7 @@ void machine_emergency_restart(void) } case BOOT_TRIPLE: - __asm__ __volatile__("lidt (%0)": :"r" (&no_idt)); + load_idt((const struct desc_ptr *)&no_idt); __asm__ __volatile__("int3"); reboot_type = BOOT_KBD; diff --git a/arch/x86/kernel/setup64.c b/arch/x86/kernel/setup64.c index e11886e..3558ac7 100644 --- a/arch/x86/kernel/setup64.c +++ b/arch/x86/kernel/setup64.c @@ -230,8 +230,8 @@ void __cpuinit cpu_init (void) memcpy(cpu_gdt(cpu), cpu_gdt_table, GDT_SIZE); cpu_gdt_descr[cpu].size = GDT_SIZE; - asm volatile("lgdt %0" :: "m" (cpu_gdt_descr[cpu])); - asm volatile("lidt %0" :: "m" (idt_descr)); + load_gdt((const struct desc_ptr *)&cpu_gdt_descr[cpu]); + load_idt((const struct desc_ptr *)&idt_descr); memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8); syscall_init(); diff --git a/arch/x86/kernel/suspend_64.c b/arch/x86/kernel/suspend_64.c index f8fafe5..622bb02 100644 --- a/arch/x86/kernel/suspend_64.c +++ b/arch/x86/kernel/suspend_64.c @@ -32,9 +32,9 @@ void __save_processor_state(struct saved_context *ctxt) /* * descriptor tables */ - asm volatile ("sgdt %0" : "=m" (ctxt->gdt_limit)); - asm volatile ("sidt %0" : "=m" (ctxt->idt_limit)); - asm volatile ("str %0" : "=m" (ctxt->tr)); + store_gdt((struct desc_ptr *)&ctxt->gdt_limit); + store_idt((struct desc_ptr *)&ctxt->idt_limit); + store_tr(ctxt->tr); /* XMM0..XMM15 should be handled by kernel_fpu_begin(). */ /* @@ -91,8 +91,9 @@ void __restore_processor_state(struct saved_context *ctxt) * now restore the descriptor tables to their proper values * ltr is done i fix_processor_context(). */ - asm volatile ("lgdt %0" :: "m" (ctxt->gdt_limit)); - asm volatile ("lidt %0" :: "m" (ctxt->idt_limit)); + load_gdt((const struct desc_ptr *)&ctxt->gdt_limit); + load_idt((const struct desc_ptr *)&ctxt->idt_limit); + /* * segment registers diff --git a/include/asm-x86/desc_64.h b/include/asm-x86/desc_64.h index ac991b5..7d9c938 100644 --- a/include/asm-x86/desc_64.h +++ b/include/asm-x86/desc_64.h @@ -20,6 +20,16 @@ extern struct desc_struct cpu_gdt_table[GDT_ENTRIES]; #define load_LDT_desc() asm volatile("lldt %w0"::"r" (GDT_ENTRY_LDT*8)) #define clear_LDT() asm volatile("lldt %w0"::"r" (0)) +static inline unsigned long __store_tr(void) +{ + unsigned long tr; + + asm volatile ("str %w0":"=r" (tr)); + return tr; +} + +#define store_tr(tr) (tr) = __store_tr() + /* * This is the ldt that every process will get unless we need * something other than this. @@ -31,6 +41,16 @@ extern struct desc_ptr cpu_gdt_descr[]; /* the cpu gdt accessor */ #define cpu_gdt(_cpu) ((struct desc_struct *)cpu_gdt_descr[_cpu].address) +static inline void load_gdt(const struct desc_ptr *ptr) +{ + asm volatile("lgdt %w0"::"m" (*ptr)); +} + +static inline void store_gdt(struct desc_ptr *ptr) +{ + asm("sgdt %w0":"=m" (*ptr)); +} + static inline void _set_gate(void *adr, unsigned type, unsigned long func, unsigned dpl, unsigned ist) { struct gate_struct s; @@ -71,6 +91,16 @@ static inline void set_system_gate_ist(int nr, void *func, unsigned ist) _set_gate(&idt_table[nr], GATE_INTERRUPT, (unsigned long) func, 3, ist); } +static inline void load_idt(const struct desc_ptr *ptr) +{ + asm volatile("lidt %w0"::"m" (*ptr)); +} + +static inline void store_idt(struct desc_ptr *dtr) +{ + asm("sidt %w0":"=m" (*dtr)); +} + static inline void set_tssldt_descriptor(void *ptr, unsigned long tss, unsigned type, unsigned size) { -- 2.7.4