From 57594742a2b545f8f114cda34f15650be8ae976d Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Sun, 19 Jul 2009 00:11:06 +0900 Subject: [PATCH] x86: Introduce set_desc_base() and set_desc_limit() Rename set_base()/set_limit to set_desc_base()/set_desc_limit() and rewrite them in C. These are naturally introduced by the idea of get_desc_base()/get_desc_limit(). The conversion actually found the bug in apm_32.c: bad_bios_desc is written at run-time, but it is defined const variable. Signed-off-by: Akinobu Mita LKML-Reference: <20090718151105.GC11294@localhost.localdomain> Signed-off-by: Ingo Molnar --- arch/x86/include/asm/desc.h | 13 +++++++++++++ arch/x86/include/asm/stackprotector.h | 4 +--- arch/x86/include/asm/system.h | 27 --------------------------- arch/x86/kernel/apm_32.c | 18 +++++++++--------- drivers/pnp/pnpbios/bioscalls.c | 21 +++++++++++---------- 5 files changed, 34 insertions(+), 49 deletions(-) diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h index c993e9e0fed4..e8de2f6f5ca5 100644 --- a/arch/x86/include/asm/desc.h +++ b/arch/x86/include/asm/desc.h @@ -291,11 +291,24 @@ static inline unsigned long get_desc_base(const struct desc_struct *desc) return desc->base0 | ((desc->base1) << 16) | ((desc->base2) << 24); } +static inline void set_desc_base(struct desc_struct *desc, unsigned long base) +{ + desc->base0 = base & 0xffff; + desc->base1 = (base >> 16) & 0xff; + desc->base2 = (base >> 24) & 0xff; +} + static inline unsigned long get_desc_limit(const struct desc_struct *desc) { return desc->limit0 | (desc->limit << 16); } +static inline void set_desc_limit(struct desc_struct *desc, unsigned long limit) +{ + desc->limit0 = limit & 0xffff; + desc->limit = (limit >> 16) & 0xf; +} + static inline void _set_gate(int gate, unsigned type, void *addr, unsigned dpl, unsigned ist, unsigned seg) { diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h index c2d742c6e15f..cdc5e0b126a7 100644 --- a/arch/x86/include/asm/stackprotector.h +++ b/arch/x86/include/asm/stackprotector.h @@ -90,9 +90,7 @@ static inline void setup_stack_canary_segment(int cpu) struct desc_struct desc; desc = gdt_table[GDT_ENTRY_STACK_CANARY]; - desc.base0 = canary & 0xffff; - desc.base1 = (canary >> 16) & 0xff; - desc.base2 = (canary >> 24) & 0xff; + set_desc_base(&desc, canary); write_gdt_entry(gdt_table, GDT_ENTRY_STACK_CANARY, &desc, DESCTYPE_S); #endif } diff --git a/arch/x86/include/asm/system.h b/arch/x86/include/asm/system.h index 643c59b4bc6e..75c49c782e20 100644 --- a/arch/x86/include/asm/system.h +++ b/arch/x86/include/asm/system.h @@ -150,33 +150,6 @@ do { \ #endif #ifdef __KERNEL__ -#define _set_base(addr, base) do { unsigned long __pr; \ -__asm__ __volatile__ ("movw %%dx,%1\n\t" \ - "rorl $16,%%edx\n\t" \ - "movb %%dl,%2\n\t" \ - "movb %%dh,%3" \ - :"=&d" (__pr) \ - :"m" (*((addr)+2)), \ - "m" (*((addr)+4)), \ - "m" (*((addr)+7)), \ - "0" (base) \ - ); } while (0) - -#define _set_limit(addr, limit) do { unsigned long __lr; \ -__asm__ __volatile__ ("movw %%dx,%1\n\t" \ - "rorl $16,%%edx\n\t" \ - "movb %2,%%dh\n\t" \ - "andb $0xf0,%%dh\n\t" \ - "orb %%dh,%%dl\n\t" \ - "movb %%dl,%2" \ - :"=&d" (__lr) \ - :"m" (*(addr)), \ - "m" (*((addr)+6)), \ - "0" (limit) \ - ); } while (0) - -#define set_base(ldt, base) _set_base(((char *)&(ldt)) , (base)) -#define set_limit(ldt, limit) _set_limit(((char *)&(ldt)) , ((limit)-1)) extern void native_load_gs_index(unsigned); diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c index 79302e9a33a4..b5e841bd60d9 100644 --- a/arch/x86/kernel/apm_32.c +++ b/arch/x86/kernel/apm_32.c @@ -403,7 +403,7 @@ static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue); static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue); static struct apm_user *user_list; static DEFINE_SPINLOCK(user_list_lock); -static const struct desc_struct bad_bios_desc = { { { 0, 0x00409200 } } }; +static struct desc_struct bad_bios_desc = { { { 0, 0x00409200 } } }; static const char driver_version[] = "1.16ac"; /* no spaces */ @@ -2337,8 +2337,8 @@ static int __init apm_init(void) * This is for buggy BIOS's that refer to (real mode) segment 0x40 * even though they are called in protected mode. */ - set_base(bad_bios_desc, __va((unsigned long)0x40 << 4)); - _set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4)); + set_desc_base(&bad_bios_desc, (unsigned long)__va(0x40UL << 4)); + set_desc_limit(&bad_bios_desc, 4095 - (0x40 << 4)); /* * Set up the long jump entry point to the APM BIOS, which is called @@ -2358,12 +2358,12 @@ static int __init apm_init(void) * code to that CPU. */ gdt = get_cpu_gdt_table(0); - set_base(gdt[APM_CS >> 3], - __va((unsigned long)apm_info.bios.cseg << 4)); - set_base(gdt[APM_CS_16 >> 3], - __va((unsigned long)apm_info.bios.cseg_16 << 4)); - set_base(gdt[APM_DS >> 3], - __va((unsigned long)apm_info.bios.dseg << 4)); + set_desc_base(&gdt[APM_CS >> 3], + (unsigned long)__va((unsigned long)apm_info.bios.cseg << 4)); + set_desc_base(&gdt[APM_CS_16 >> 3], + (unsigned long)__va((unsigned long)apm_info.bios.cseg_16 << 4)); + set_desc_base(&gdt[APM_DS >> 3], + (unsigned long)__va((unsigned long)apm_info.bios.dseg << 4)); proc_create("apm", 0, NULL, &apm_file_ops); diff --git a/drivers/pnp/pnpbios/bioscalls.c b/drivers/pnp/pnpbios/bioscalls.c index 7e6b5a3b3281..45ad3e9cc362 100644 --- a/drivers/pnp/pnpbios/bioscalls.c +++ b/drivers/pnp/pnpbios/bioscalls.c @@ -55,9 +55,9 @@ __asm__(".text \n" #define Q2_SET_SEL(cpu, selname, address, size) \ do { \ -struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \ -set_base(gdt[(selname) >> 3], (u32)(address)); \ -set_limit(gdt[(selname) >> 3], size); \ + struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \ + set_desc_base(&gdt[(selname) >> 3], (u32)(address)); \ + set_desc_limit(&gdt[(selname) >> 3], (size) - 1); \ } while(0) static struct desc_struct bad_bios_desc; @@ -479,16 +479,17 @@ void pnpbios_calls_init(union pnp_bios_install_struct *header) bad_bios_desc.a = 0; bad_bios_desc.b = 0x00409200; - set_base(bad_bios_desc, __va((unsigned long)0x40 << 4)); - _set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4)); + set_desc_base(&bad_bios_desc, (unsigned long)__va(0x40UL << 4)); + set_desc_limit(&bad_bios_desc, 4095 - (0x40 << 4)); for_each_possible_cpu(i) { struct desc_struct *gdt = get_cpu_gdt_table(i); if (!gdt) continue; - set_base(gdt[GDT_ENTRY_PNPBIOS_CS32], &pnp_bios_callfunc); - set_base(gdt[GDT_ENTRY_PNPBIOS_CS16], - __va(header->fields.pm16cseg)); - set_base(gdt[GDT_ENTRY_PNPBIOS_DS], - __va(header->fields.pm16dseg)); + set_desc_base(&gdt[GDT_ENTRY_PNPBIOS_CS32], + (unsigned long)&pnp_bios_callfunc); + set_desc_base(&gdt[GDT_ENTRY_PNPBIOS_CS16], + (unsigned long)__va(header->fields.pm16cseg)); + set_desc_base(&gdt[GDT_ENTRY_PNPBIOS_DS], + (unsigned long)__va(header->fields.pm16dseg)); } } -- GitLab