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authorRoland McGrath <roland@redhat.com>2008-01-30 13:30:46 +0100
committerIngo Molnar <mingo@elte.hu>2008-01-30 13:30:46 +0100
commitefd1ca52d04d2f6df337a3332cee56cd60e6d4c4 (patch)
treecf1e630d25cc45f399388f5fc996d86cf3bcf9ff /arch/x86/kernel/tls.c
parent13abd0e50433092c41551bc13c32268028b6d663 (diff)
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 <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Zachary Amsden <zach@vmware.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/kernel/tls.c')
-rw-r--r--arch/x86/kernel/tls.c96
1 files changed, 37 insertions, 59 deletions
diff --git a/arch/x86/kernel/tls.c b/arch/x86/kernel/tls.c
index 5291596f19b..67a377621b1 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 == &current->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(&current->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(&current->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);
}