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>
This commit is contained in:
Roland McGrath 2008-01-30 13:30:46 +01:00 committed by Ingo Molnar
parent 13abd0e504
commit efd1ca52d0
9 changed files with 76 additions and 301 deletions

View File

@ -643,8 +643,8 @@ ia32_sys_call_table:
.quad compat_sys_futex /* 240 */
.quad compat_sys_sched_setaffinity
.quad compat_sys_sched_getaffinity
.quad sys32_set_thread_area
.quad sys32_get_thread_area
.quad sys_set_thread_area
.quad sys_get_thread_area
.quad compat_sys_io_setup /* 245 */
.quad sys_io_destroy
.quad compat_sys_io_getevents

View File

@ -10,6 +10,7 @@ obj-y := process_32.o signal_32.o entry_32.o traps_32.o irq_32.o \
pci-dma_32.o i386_ksyms_32.o i387_32.o bootflag.o e820_32.o\
quirks.o i8237.o topology.o alternative.o i8253.o tsc_32.o io_delay.o rtc.o
obj-y += tls.o
obj-$(CONFIG_STACKTRACE) += stacktrace.o
obj-y += cpu/
obj-y += acpi/

View File

@ -501,32 +501,15 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long esp,
set_tsk_thread_flag(p, TIF_IO_BITMAP);
}
err = 0;
/*
* Set a new TLS for the child thread?
*/
if (clone_flags & CLONE_SETTLS) {
struct desc_struct *desc;
struct user_desc info;
int idx;
if (clone_flags & CLONE_SETTLS)
err = do_set_thread_area(p, -1,
(struct user_desc __user *)childregs->esi, 0);
err = -EFAULT;
if (copy_from_user(&info, (void __user *)childregs->esi, sizeof(info)))
goto out;
err = -EINVAL;
if (LDT_empty(&info))
goto out;
idx = info.entry_number;
if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
goto out;
desc = p->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
desc->a = LDT_entry_a(&info);
desc->b = LDT_entry_b(&info);
}
err = 0;
out:
if (err && p->thread.io_bitmap_ptr) {
kfree(p->thread.io_bitmap_ptr);
p->thread.io_bitmap_max = 0;
@ -872,120 +855,6 @@ unsigned long get_wchan(struct task_struct *p)
return 0;
}
/*
* sys_alloc_thread_area: get a yet unused TLS descriptor index.
*/
static int get_free_idx(void)
{
struct thread_struct *t = &current->thread;
int idx;
for (idx = 0; idx < GDT_ENTRY_TLS_ENTRIES; idx++)
if (desc_empty(t->tls_array + idx))
return idx + GDT_ENTRY_TLS_MIN;
return -ESRCH;
}
/*
* Set a given TLS descriptor:
*/
asmlinkage int sys_set_thread_area(struct user_desc __user *u_info)
{
struct thread_struct *t = &current->thread;
struct user_desc info;
struct desc_struct *desc;
int cpu, idx;
if (copy_from_user(&info, u_info, sizeof(info)))
return -EFAULT;
idx = info.entry_number;
/*
* index -1 means the kernel should try to find and
* allocate an empty descriptor:
*/
if (idx == -1) {
idx = get_free_idx();
if (idx < 0)
return idx;
if (put_user(idx, &u_info->entry_number))
return -EFAULT;
}
if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
return -EINVAL;
desc = t->tls_array + idx - GDT_ENTRY_TLS_MIN;
/*
* We must not get preempted while modifying the TLS.
*/
cpu = get_cpu();
if (LDT_empty(&info)) {
desc->a = 0;
desc->b = 0;
} else {
desc->a = LDT_entry_a(&info);
desc->b = LDT_entry_b(&info);
}
load_TLS(t, cpu);
put_cpu();
return 0;
}
/*
* Get the current Thread-Local Storage area:
*/
#define GET_BASE(desc) ( \
(((desc)->a >> 16) & 0x0000ffff) | \
(((desc)->b << 16) & 0x00ff0000) | \
( (desc)->b & 0xff000000) )
#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)
asmlinkage int sys_get_thread_area(struct user_desc __user *u_info)
{
struct user_desc info;
struct desc_struct *desc;
int idx;
if (get_user(idx, &u_info->entry_number))
return -EFAULT;
if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
return -EINVAL;
memset(&info, 0, sizeof(info));
desc = current->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
info.entry_number = idx;
info.base_addr = GET_BASE(desc);
info.limit = GET_LIMIT(desc);
info.seg_32bit = GET_32BIT(desc);
info.contents = GET_CONTENTS(desc);
info.read_exec_only = !GET_WRITABLE(desc);
info.limit_in_pages = GET_LIMIT_PAGES(desc);
info.seg_not_present = !GET_PRESENT(desc);
info.useable = GET_USEABLE(desc);
if (copy_to_user(u_info, &info, sizeof(info)))
return -EFAULT;
return 0;
}
unsigned long arch_align_stack(unsigned long sp)
{
if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)

View File

@ -524,7 +524,8 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long rsp,
if (clone_flags & CLONE_SETTLS) {
#ifdef CONFIG_IA32_EMULATION
if (test_thread_flag(TIF_IA32))
err = ia32_child_tls(p, childregs);
err = do_set_thread_area(p, -1,
(struct user_desc __user *)childregs->rsi, 0);
else
#endif
err = do_arch_prctl(p, ARCH_SET_FS, childregs->r8);

View File

@ -276,85 +276,6 @@ void ptrace_disable(struct task_struct *child)
clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
}
/*
* Perform get_thread_area on behalf of the traced child.
*/
static int
ptrace_get_thread_area(struct task_struct *child,
int idx, struct user_desc __user *user_desc)
{
struct user_desc info;
struct desc_struct *desc;
/*
* Get the current Thread-Local Storage area:
*/
#define GET_BASE(desc) ( \
(((desc)->a >> 16) & 0x0000ffff) | \
(((desc)->b << 16) & 0x00ff0000) | \
( (desc)->b & 0xff000000) )
#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)
if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
return -EINVAL;
desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
info.entry_number = idx;
info.base_addr = GET_BASE(desc);
info.limit = GET_LIMIT(desc);
info.seg_32bit = GET_32BIT(desc);
info.contents = GET_CONTENTS(desc);
info.read_exec_only = !GET_WRITABLE(desc);
info.limit_in_pages = GET_LIMIT_PAGES(desc);
info.seg_not_present = !GET_PRESENT(desc);
info.useable = GET_USEABLE(desc);
if (copy_to_user(user_desc, &info, sizeof(info)))
return -EFAULT;
return 0;
}
/*
* Perform set_thread_area on behalf of the traced child.
*/
static int
ptrace_set_thread_area(struct task_struct *child,
int idx, struct user_desc __user *user_desc)
{
struct user_desc info;
struct desc_struct *desc;
if (copy_from_user(&info, user_desc, sizeof(info)))
return -EFAULT;
if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
return -EINVAL;
desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
if (LDT_empty(&info)) {
desc->a = 0;
desc->b = 0;
} else {
desc->a = LDT_entry_a(&info);
desc->b = LDT_entry_b(&info);
}
return 0;
}
long arch_ptrace(struct task_struct *child, long request, long addr, long data)
{
struct user * dummy = NULL;
@ -601,13 +522,17 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
}
case PTRACE_GET_THREAD_AREA:
ret = ptrace_get_thread_area(child, addr,
(struct user_desc __user *) data);
if (addr < 0)
return -EIO;
ret = do_get_thread_area(child, addr,
(struct user_desc __user *) data);
break;
case PTRACE_SET_THREAD_AREA:
ret = ptrace_set_thread_area(child, addr,
(struct user_desc __user *) data);
if (addr < 0)
return -EIO;
ret = do_set_thread_area(child, addr,
(struct user_desc __user *) data, 0);
break;
default:

View File

@ -474,23 +474,19 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
64bit debugger to fully examine them too. Better
don't use it against 64bit processes, use
PTRACE_ARCH_PRCTL instead. */
case PTRACE_SET_THREAD_AREA: {
struct user_desc __user *p;
int old;
p = (struct user_desc __user *)data;
get_user(old, &p->entry_number);
put_user(addr, &p->entry_number);
ret = do_set_thread_area(&child->thread, p);
put_user(old, &p->entry_number);
break;
case PTRACE_GET_THREAD_AREA:
p = (struct user_desc __user *)data;
get_user(old, &p->entry_number);
put_user(addr, &p->entry_number);
ret = do_get_thread_area(&child->thread, p);
put_user(old, &p->entry_number);
if (addr < 0)
return -EIO;
ret = do_get_thread_area(child, addr,
(struct user_desc __user *) data);
break;
case PTRACE_SET_THREAD_AREA:
if (addr < 0)
return -EIO;
ret = do_set_thread_area(child, addr,
(struct user_desc __user *) data, 0);
break;
}
#endif
/* normal 64bit interface to access TLS data.
Works just like arch_prctl, except that the arguments

View File

@ -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_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)
#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)
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);
}

View File

@ -159,12 +159,6 @@ struct ustat32 {
#define IA32_STACK_TOP IA32_PAGE_OFFSET
#ifdef __KERNEL__
struct user_desc;
struct siginfo_t;
int do_get_thread_area(struct thread_struct *t, struct user_desc __user *info);
int do_set_thread_area(struct thread_struct *t, struct user_desc __user *info);
int ia32_child_tls(struct task_struct *p, struct pt_regs *childregs);
struct linux_binprm;
extern int ia32_setup_arg_pages(struct linux_binprm *bprm,
unsigned long stack_top, int exec_stack);

View File

@ -137,6 +137,17 @@ enum {
};
#endif /* __KERNEL__ */
#endif /* !__i386__ */
#ifdef __KERNEL__
struct user_desc;
extern int do_get_thread_area(struct task_struct *p, int idx,
struct user_desc __user *info);
extern int do_set_thread_area(struct task_struct *p, int idx,
struct user_desc __user *info, int can_allocate);
#endif /* __KERNEL__ */
#endif /* !__ASSEMBLY__ */
#endif