x86: TLS cleanup
authorRoland McGrath <roland@redhat.com>
Wed, 30 Jan 2008 12:30:46 +0000 (13:30 +0100)
committerIngo Molnar <mingo@elte.hu>
Wed, 30 Jan 2008 12:30:46 +0000 (13:30 +0100)
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>
arch/x86/ia32/ia32entry.S
arch/x86/kernel/Makefile_32
arch/x86/kernel/process_32.c
arch/x86/kernel/process_64.c
arch/x86/kernel/ptrace_32.c
arch/x86/kernel/ptrace_64.c
arch/x86/kernel/tls.c
include/asm-x86/ia32.h
include/asm-x86/ptrace.h

index 2499a324feaab9c576692ae6f0933d1d9d14c33b..0db0a6291bbd06d059c654ce58f8e5d387d685c0 100644 (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
index 2c9596b9349cf44a699d337592b80c7acc2e5253..9a6577a746bab8071db2096fb0cbd41d33320fcc 100644 (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/
index 631af167bc51c376c38571518799a38d0e77c6bf..4d66a56280d3ee86f048cd1d998a8dd7c1ed24e0 100644 (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;
-
-               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);
-       }
+       if (clone_flags & CLONE_SETTLS)
+               err = do_set_thread_area(p, -1,
+                       (struct user_desc __user *)childregs->esi, 0);
 
-       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)
index 9ea1d7546f808cd9f6c98c4bdad8d05f69ea53c3..ccc9d68d5a586717a23a88508cbdc72f12c2b413 100644 (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); 
index ff5431cc03ee8ea949704fa19d6f289afc7f74bd..09227cfb7c4c3733021620a00fc66fbf18266402 100644 (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:
index 1edece36044c5471dbccc112fe8c9a9115746bae..375fadc23a25317fa26ad937f1935813ef3d850d 100644 (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
index 5291596f19b0b3a5658247e029a5f6567b11f8c7..67a377621b129df6a414d7f8f999cc9965dbe5c8 100644 (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_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);
 }
index 0190b7c4e319cc1a153a23ba2030267ba8694b4e..aa9733206e29cdb6c46fba5a6d00d6db7ecceafe 100644 (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);
index 51ddb2590870f96d0e6f0b373cd7a91e22b61d49..105d1534eaf46cb418db16e6819ba88d7779be3e 100644 (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