x86: x86 user_regset TLS

This adds accessor functions in the user_regset style for the TLS data. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

x86: x86 user_regset TLS
This adds accessor functions in the user_regset style for the TLS data. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Roland McGrath · Ingo Molnar
1 parent 1bd5718ce5
Showing 2 changed files with 104 additions and 6 deletions Side-by-side Diff
arch/x86/kernel/tls.c
arch/x86/kernel/tls.h
@@ -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 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 @@
 	 */
 	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 == &current->thread)
 		load_TLS(t, cpu);
@@ -77,7 +84,7 @@
 	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;
 }
@@ -133,5 +140,75 @@
 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;
 }
+/*
+ * 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 */
...	...	@@ -2,6 +2,7 @@
2	2	#include <linux/errno.h>
3	3	#include <linux/sched.h>
4	4	#include <linux/user.h>
	5	+#include <linux/regset.h>
5	6
6	7	#include <asm/uaccess.h>
7	8	#include <asm/desc.h>
...	...	@@ -10,6 +11,8 @@
10	11	#include <asm/processor.h>
11	12	#include <asm/proto.h>
12	13
	14	+#include "tls.h"
	15	+
13	16	/*
14	17	* sys_alloc_thread_area: get a yet unused TLS descriptor index.
15	18	*/
...	...	@@ -25,7 +28,7 @@
25	28	}
26	29
27	30	static void set_tls_desc(struct task_struct *p, int idx,
28		- const struct user_desc *info)
	31	+ const struct user_desc *info, int n)
29	32	{
30	33	struct thread_struct *t = &p->thread;
31	34	struct desc_struct *desc = &t->tls_array[idx - GDT_ENTRY_TLS_MIN];
...	...	@@ -36,10 +39,14 @@
36	39	*/
37	40	cpu = get_cpu();
38	41
39		- if (LDT_empty(info))
40		- desc->a = desc->b = 0;
41		- else
42		- fill_ldt(desc, info);
	42	+ while (n-- > 0) {
	43	+ if (LDT_empty(info))
	44	+ desc->a = desc->b = 0;
	45	+ else
	46	+ fill_ldt(desc, info);
	47	+ ++info;
	48	+ ++desc;
	49	+ }
43	50
44	51	if (t == &current->thread)
45	52	load_TLS(t, cpu);
...	...	@@ -77,7 +84,7 @@
77	84	if (idx < GDT_ENTRY_TLS_MIN \|\| idx > GDT_ENTRY_TLS_MAX)
78	85	return -EINVAL;
79	86
80		- set_tls_desc(p, idx, &info);
	87	+ set_tls_desc(p, idx, &info, 1);
81	88
82	89	return 0;
83	90	}
...	...	@@ -133,5 +140,75 @@
133	140	asmlinkage int sys_get_thread_area(struct user_desc __user *u_info)
134	141	{
135	142	return do_get_thread_area(current, -1, u_info);
	143	+}
	144	+
	145	+int regset_tls_active(struct task_struct *target,
	146	+ const struct user_regset *regset)
	147	+{
	148	+ struct thread_struct *t = &target->thread;
	149	+ int n = GDT_ENTRY_TLS_ENTRIES;
	150	+ while (n > 0 && desc_empty(&t->tls_array[n - 1]))
	151	+ --n;
	152	+ return n;
	153	+}
	154	+
	155	+int regset_tls_get(struct task_struct target, const struct user_regset regset,
	156	+ unsigned int pos, unsigned int count,
	157	+ void kbuf, void __user ubuf)
	158	+{
	159	+ const struct desc_struct *tls;
	160	+
	161	+ if (pos > GDT_ENTRY_TLS_ENTRIES * sizeof(struct user_desc) \|\|
	162	+ (pos % sizeof(struct user_desc)) != 0 \|\|
	163	+ (count % sizeof(struct user_desc)) != 0)
	164	+ return -EINVAL;
	165	+
	166	+ pos /= sizeof(struct user_desc);
	167	+ count /= sizeof(struct user_desc);
	168	+
	169	+ tls = &target->thread.tls_array[pos];
	170	+
	171	+ if (kbuf) {
	172	+ struct user_desc *info = kbuf;
	173	+ while (count-- > 0)
	174	+ fill_user_desc(info++, GDT_ENTRY_TLS_MIN + pos++,
	175	+ tls++);
	176	+ } else {
	177	+ struct user_desc __user *u_info = ubuf;
	178	+ while (count-- > 0) {
	179	+ struct user_desc info;
	180	+ fill_user_desc(&info, GDT_ENTRY_TLS_MIN + pos++, tls++);
	181	+ if (__copy_to_user(u_info++, &info, sizeof(info)))
	182	+ return -EFAULT;
	183	+ }
	184	+ }
	185	+
	186	+ return 0;
	187	+}
	188	+
	189	+int regset_tls_set(struct task_struct target, const struct user_regset regset,
	190	+ unsigned int pos, unsigned int count,
	191	+ const void kbuf, const void __user ubuf)
	192	+{
	193	+ struct user_desc infobuf[GDT_ENTRY_TLS_ENTRIES];
	194	+ const struct user_desc *info;
	195	+
	196	+ if (pos > GDT_ENTRY_TLS_ENTRIES * sizeof(struct user_desc) \|\|
	197	+ (pos % sizeof(struct user_desc)) != 0 \|\|
	198	+ (count % sizeof(struct user_desc)) != 0)
	199	+ return -EINVAL;
	200	+
	201	+ if (kbuf)
	202	+ info = kbuf;
	203	+ else if (__copy_from_user(infobuf, ubuf, count))
	204	+ return -EFAULT;
	205	+ else
	206	+ info = infobuf;
	207	+
	208	+ set_tls_desc(target,
	209	+ GDT_ENTRY_TLS_MIN + (pos / sizeof(struct user_desc)),
	210	+ info, count / sizeof(struct user_desc));
	211	+
	212	+ return 0;
136	213	}
	1	+/*
	2	+ * Internal declarations for x86 TLS implementation functions.
	3	+ *
	4	+ * Copyright (C) 2007 Red Hat, Inc. All rights reserved.
	5	+ *
	6	+ * This copyrighted material is made available to anyone wishing to use,
	7	+ * modify, copy, or redistribute it subject to the terms and conditions
	8	+ * of the GNU General Public License v.2.
	9	+ *
	10	+ * Red Hat Author: Roland McGrath.
	11	+ */
	12	+
	13	+#ifndef _ARCH_X86_KERNEL_TLS_H
	14	+
	15	+#include <linux/regset.h>
	16	+
	17	+extern user_regset_active_fn regset_tls_active;
	18	+extern user_regset_get_fn regset_tls_get;
	19	+extern user_regset_set_fn regset_tls_set;
	20	+
	21	+#endif /* _ARCH_X86_KERNEL_TLS_H */