From efd1ca52d04d2f6df337a3332cee56cd60e6d4c4 Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Wed, 30 Jan 2008 13:30:46 +0100 Subject: x86: TLS cleanup This consolidates the four different places that implemented the same encoding magic for the GDT-slot 32-bit TLS support. The old tls32.c was renamed and is now only slightly modified to be the shared implementation. Signed-off-by: Roland McGrath Cc: Andrew Morton Cc: Zachary Amsden Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/tls.c | 96 ++++++++++++++++++++------------------------------- 1 file changed, 37 insertions(+), 59 deletions(-) (limited to 'arch/x86/kernel/tls.c') diff --git a/arch/x86/kernel/tls.c b/arch/x86/kernel/tls.c index 5291596f19b0..67a377621b12 100644 --- a/arch/x86/kernel/tls.c +++ b/arch/x86/kernel/tls.c @@ -19,31 +19,34 @@ static int get_free_idx(void) int idx; for (idx = 0; idx < GDT_ENTRY_TLS_ENTRIES; idx++) - if (desc_empty((struct n_desc_struct *)(t->tls_array) + idx)) + if (desc_empty(&t->tls_array[idx])) return idx + GDT_ENTRY_TLS_MIN; return -ESRCH; } /* * Set a given TLS descriptor: - * When you want addresses > 32bit use arch_prctl() */ -int do_set_thread_area(struct thread_struct *t, struct user_desc __user *u_info) +int do_set_thread_area(struct task_struct *p, int idx, + struct user_desc __user *u_info, + int can_allocate) { + struct thread_struct *t = &p->thread; struct user_desc info; - struct n_desc_struct *desc; - int cpu, idx; + u32 *desc; + int cpu; if (copy_from_user(&info, u_info, sizeof(info))) return -EFAULT; - idx = info.entry_number; + if (idx == -1) + idx = info.entry_number; /* * index -1 means the kernel should try to find and * allocate an empty descriptor: */ - if (idx == -1) { + if (idx == -1 && can_allocate) { idx = get_free_idx(); if (idx < 0) return idx; @@ -54,7 +57,7 @@ int do_set_thread_area(struct thread_struct *t, struct user_desc __user *u_info) if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) return -EINVAL; - desc = ((struct n_desc_struct *)t->tls_array) + idx - GDT_ENTRY_TLS_MIN; + desc = (u32 *) &t->tls_array[idx - GDT_ENTRY_TLS_MIN]; /* * We must not get preempted while modifying the TLS. @@ -62,11 +65,11 @@ int do_set_thread_area(struct thread_struct *t, struct user_desc __user *u_info) cpu = get_cpu(); if (LDT_empty(&info)) { - desc->a = 0; - desc->b = 0; + desc[0] = 0; + desc[1] = 0; } else { - desc->a = LDT_entry_a(&info); - desc->b = LDT_entry_b(&info); + desc[0] = LDT_entry_a(&info); + desc[1] = LDT_entry_b(&info); } if (t == ¤t->thread) load_TLS(t, cpu); @@ -75,9 +78,9 @@ int do_set_thread_area(struct thread_struct *t, struct user_desc __user *u_info) return 0; } -asmlinkage long sys32_set_thread_area(struct user_desc __user *u_info) +asmlinkage int sys_set_thread_area(struct user_desc __user *u_info) { - return do_set_thread_area(¤t->thread, u_info); + return do_set_thread_area(current, -1, u_info, 1); } @@ -85,34 +88,32 @@ asmlinkage long sys32_set_thread_area(struct user_desc __user *u_info) * Get the current Thread-Local Storage area: */ -#define GET_LIMIT(desc) ( \ - ((desc)->a & 0x0ffff) | \ - ((desc)->b & 0xf0000) ) - -#define GET_32BIT(desc) (((desc)->b >> 22) & 1) -#define GET_CONTENTS(desc) (((desc)->b >> 10) & 3) -#define GET_WRITABLE(desc) (((desc)->b >> 9) & 1) -#define GET_LIMIT_PAGES(desc) (((desc)->b >> 23) & 1) -#define GET_PRESENT(desc) (((desc)->b >> 15) & 1) -#define GET_USEABLE(desc) (((desc)->b >> 20) & 1) -#define GET_LONGMODE(desc) (((desc)->b >> 21) & 1) - -int do_get_thread_area(struct thread_struct *t, struct user_desc __user *u_info) +#define GET_LIMIT(desc) (((desc)[0] & 0x0ffff) | ((desc)[1] & 0xf0000)) +#define GET_32BIT(desc) (((desc)[1] >> 22) & 1) +#define GET_CONTENTS(desc) (((desc)[1] >> 10) & 3) +#define GET_WRITABLE(desc) (((desc)[1] >> 9) & 1) +#define GET_LIMIT_PAGES(desc) (((desc)[1] >> 23) & 1) +#define GET_PRESENT(desc) (((desc)[1] >> 15) & 1) +#define GET_USEABLE(desc) (((desc)[1] >> 20) & 1) +#define GET_LONGMODE(desc) (((desc)[1] >> 21) & 1) + +int do_get_thread_area(struct task_struct *p, int idx, + struct user_desc __user *u_info) { + struct thread_struct *t = &p->thread; struct user_desc info; - struct n_desc_struct *desc; - int idx; + u32 *desc; - if (get_user(idx, &u_info->entry_number)) + if (idx == -1 && get_user(idx, &u_info->entry_number)) return -EFAULT; if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) return -EINVAL; - desc = ((struct n_desc_struct *)t->tls_array) + idx - GDT_ENTRY_TLS_MIN; + desc = (u32 *) &t->tls_array[idx - GDT_ENTRY_TLS_MIN]; memset(&info, 0, sizeof(struct user_desc)); info.entry_number = idx; - info.base_addr = get_desc_base(desc); + info.base_addr = get_desc_base((void *)desc); info.limit = GET_LIMIT(desc); info.seg_32bit = GET_32BIT(desc); info.contents = GET_CONTENTS(desc); @@ -120,39 +121,16 @@ int do_get_thread_area(struct thread_struct *t, struct user_desc __user *u_info) info.limit_in_pages = GET_LIMIT_PAGES(desc); info.seg_not_present = !GET_PRESENT(desc); info.useable = GET_USEABLE(desc); +#ifdef CONFIG_X86_64 info.lm = GET_LONGMODE(desc); +#endif if (copy_to_user(u_info, &info, sizeof(info))) return -EFAULT; return 0; } -asmlinkage long sys32_get_thread_area(struct user_desc __user *u_info) +asmlinkage int sys_get_thread_area(struct user_desc __user *u_info) { - return do_get_thread_area(¤t->thread, u_info); -} - - -int ia32_child_tls(struct task_struct *p, struct pt_regs *childregs) -{ - struct n_desc_struct *desc; - struct user_desc info; - struct user_desc __user *cp; - int idx; - - cp = (void __user *)childregs->rsi; - if (copy_from_user(&info, cp, sizeof(info))) - return -EFAULT; - if (LDT_empty(&info)) - return -EINVAL; - - idx = info.entry_number; - if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) - return -EINVAL; - - desc = (struct n_desc_struct *)(p->thread.tls_array) + idx - GDT_ENTRY_TLS_MIN; - desc->a = LDT_entry_a(&info); - desc->b = LDT_entry_b(&info); - - return 0; + return do_get_thread_area(current, -1, u_info); } -- cgit v1.2.3