diff options
| -rw-r--r-- | arch/x86/kernel/tls.c | 89 | ||||
| -rw-r--r-- | arch/x86/kernel/tls.h | 21 |
2 files changed, 104 insertions, 6 deletions
diff --git a/arch/x86/kernel/tls.c b/arch/x86/kernel/tls.c index f11c92a3faac..6dfd4e76661a 100644 --- a/arch/x86/kernel/tls.c +++ b/arch/x86/kernel/tls.c @@ -2,6 +2,7 @@ #include <linux/errno.h> #include <linux/sched.h> #include <linux/user.h> +#include <linux/regset.h> #include <asm/uaccess.h> #include <asm/desc.h> @@ -10,6 +11,8 @@ #include <asm/processor.h> #include <asm/proto.h> +#include "tls.h" + /* * sys_alloc_thread_area: get a yet unused TLS descriptor index. */ @@ -25,7 +28,7 @@ static int get_free_idx(void) } static void set_tls_desc(struct task_struct *p, int idx, - const struct user_desc *info) + const struct user_desc *info, int n) { struct thread_struct *t = &p->thread; struct desc_struct *desc = &t->tls_array[idx - GDT_ENTRY_TLS_MIN]; @@ -36,10 +39,14 @@ static void set_tls_desc(struct task_struct *p, int idx, */ cpu = get_cpu(); - if (LDT_empty(info)) - desc->a = desc->b = 0; - else - fill_ldt(desc, info); + while (n-- > 0) { + if (LDT_empty(info)) + desc->a = desc->b = 0; + else + fill_ldt(desc, info); + ++info; + ++desc; + } if (t == ¤t->thread) load_TLS(t, cpu); @@ -77,7 +84,7 @@ int do_set_thread_area(struct task_struct *p, int idx, if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) return -EINVAL; - set_tls_desc(p, idx, &info); + set_tls_desc(p, idx, &info, 1); return 0; } @@ -134,3 +141,73 @@ asmlinkage int sys_get_thread_area(struct user_desc __user *u_info) { return do_get_thread_area(current, -1, u_info); } + +int regset_tls_active(struct task_struct *target, + const struct user_regset *regset) +{ + struct thread_struct *t = &target->thread; + int n = GDT_ENTRY_TLS_ENTRIES; + while (n > 0 && desc_empty(&t->tls_array[n - 1])) + --n; + return n; +} + +int regset_tls_get(struct task_struct *target, const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + const struct desc_struct *tls; + + if (pos > GDT_ENTRY_TLS_ENTRIES * sizeof(struct user_desc) || + (pos % sizeof(struct user_desc)) != 0 || + (count % sizeof(struct user_desc)) != 0) + return -EINVAL; + + pos /= sizeof(struct user_desc); + count /= sizeof(struct user_desc); + + tls = &target->thread.tls_array[pos]; + + if (kbuf) { + struct user_desc *info = kbuf; + while (count-- > 0) + fill_user_desc(info++, GDT_ENTRY_TLS_MIN + pos++, + tls++); + } else { + struct user_desc __user *u_info = ubuf; + while (count-- > 0) { + struct user_desc info; + fill_user_desc(&info, GDT_ENTRY_TLS_MIN + pos++, tls++); + if (__copy_to_user(u_info++, &info, sizeof(info))) + return -EFAULT; + } + } + + return 0; +} + +int regset_tls_set(struct task_struct *target, const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + struct user_desc infobuf[GDT_ENTRY_TLS_ENTRIES]; + const struct user_desc *info; + + if (pos > GDT_ENTRY_TLS_ENTRIES * sizeof(struct user_desc) || + (pos % sizeof(struct user_desc)) != 0 || + (count % sizeof(struct user_desc)) != 0) + return -EINVAL; + + if (kbuf) + info = kbuf; + else if (__copy_from_user(infobuf, ubuf, count)) + return -EFAULT; + else + info = infobuf; + + set_tls_desc(target, + GDT_ENTRY_TLS_MIN + (pos / sizeof(struct user_desc)), + info, count / sizeof(struct user_desc)); + + return 0; +} diff --git a/arch/x86/kernel/tls.h b/arch/x86/kernel/tls.h new file mode 100644 index 000000000000..2f083a2fe216 --- /dev/null +++ b/arch/x86/kernel/tls.h @@ -0,0 +1,21 @@ +/* + * Internal declarations for x86 TLS implementation functions. + * + * Copyright (C) 2007 Red Hat, Inc. All rights reserved. + * + * This copyrighted material is made available to anyone wishing to use, + * modify, copy, or redistribute it subject to the terms and conditions + * of the GNU General Public License v.2. + * + * Red Hat Author: Roland McGrath. + */ + +#ifndef _ARCH_X86_KERNEL_TLS_H + +#include <linux/regset.h> + +extern user_regset_active_fn regset_tls_active; +extern user_regset_get_fn regset_tls_get; +extern user_regset_set_fn regset_tls_set; + +#endif /* _ARCH_X86_KERNEL_TLS_H */ |