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yaml
---
r: 79732
b: refs/heads/master
c: 78aa1f6
h: refs/heads/master
v: v3
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Thomas Gleixner authored and Ingo Molnar committed Jan 30, 2008
1 parent 3089ed1 commit aa44ffe
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Showing 3 changed files with 70 additions and 61 deletions.
2 changes: 1 addition & 1 deletion [refs]
View file
Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: 2f36fa13ce49ffd000249feaedfcbefbcc83a72f
refs/heads/master: 78aa1f66f77da078357bd263fcac95fbf6bca15b
60 changes: 33 additions & 27 deletions trunk/arch/x86/kernel/ldt_32.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -17,7 +17,7 @@
#include <asm/desc.h>
#include <asm/mmu_context.h>

#ifdef CONFIG_SMP /* avoids "defined but not used" warnig */
#ifdef CONFIG_SMP
static void flush_ldt(void *null)
{
if (current->active_mm)
Expand All @@ -34,19 +34,20 @@ static int alloc_ldt(mm_context_t *pc, int mincount, int reload)
if (mincount <= pc->size)
return 0;
oldsize = pc->size;
mincount = (mincount+511)&(~511);
if (mincount*LDT_ENTRY_SIZE > PAGE_SIZE)
newldt = vmalloc(mincount*LDT_ENTRY_SIZE);
mincount = (mincount + 511) & (~511);
if (mincount * LDT_ENTRY_SIZE > PAGE_SIZE)
newldt = vmalloc(mincount * LDT_ENTRY_SIZE);
else
newldt = kmalloc(mincount*LDT_ENTRY_SIZE, GFP_KERNEL);
newldt = kmalloc(mincount * LDT_ENTRY_SIZE, GFP_KERNEL);

if (!newldt)
return -ENOMEM;

if (oldsize)
memcpy(newldt, pc->ldt, oldsize*LDT_ENTRY_SIZE);
memcpy(newldt, pc->ldt, oldsize * LDT_ENTRY_SIZE);
oldldt = pc->ldt;
memset(newldt+oldsize*LDT_ENTRY_SIZE, 0, (mincount-oldsize)*LDT_ENTRY_SIZE);
memset(newldt + oldsize * LDT_ENTRY_SIZE, 0,
(mincount - oldsize) * LDT_ENTRY_SIZE);
pc->ldt = newldt;
wmb();
pc->size = mincount;
Expand All @@ -55,6 +56,7 @@ static int alloc_ldt(mm_context_t *pc, int mincount, int reload)
if (reload) {
#ifdef CONFIG_SMP
cpumask_t mask;

preempt_disable();
load_LDT(pc);
mask = cpumask_of_cpu(smp_processor_id());
Expand All @@ -66,7 +68,7 @@ static int alloc_ldt(mm_context_t *pc, int mincount, int reload)
#endif
}
if (oldsize) {
if (oldsize*LDT_ENTRY_SIZE > PAGE_SIZE)
if (oldsize * LDT_ENTRY_SIZE > PAGE_SIZE)
vfree(oldldt);
else
kfree(oldldt);
Expand All @@ -77,9 +79,10 @@ static int alloc_ldt(mm_context_t *pc, int mincount, int reload)
static inline int copy_ldt(mm_context_t *new, mm_context_t *old)
{
int err = alloc_ldt(new, old->size, 0);

if (err < 0)
return err;
memcpy(new->ldt, old->ldt, old->size*LDT_ENTRY_SIZE);
memcpy(new->ldt, old->ldt, old->size * LDT_ENTRY_SIZE);
return 0;
}

Expand All @@ -89,7 +92,7 @@ static inline int copy_ldt(mm_context_t *new, mm_context_t *old)
*/
int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
{
struct mm_struct * old_mm;
struct mm_struct *old_mm;
int retval = 0;

mutex_init(&mm->context.lock);
Expand All @@ -111,27 +114,27 @@ void destroy_context(struct mm_struct *mm)
if (mm->context.size) {
if (mm == current->active_mm)
clear_LDT();
if (mm->context.size*LDT_ENTRY_SIZE > PAGE_SIZE)
if (mm->context.size * LDT_ENTRY_SIZE > PAGE_SIZE)
vfree(mm->context.ldt);
else
kfree(mm->context.ldt);
mm->context.size = 0;
}
}

static int read_ldt(void __user * ptr, unsigned long bytecount)
static int read_ldt(void __user *ptr, unsigned long bytecount)
{
int err;
unsigned long size;
struct mm_struct * mm = current->mm;
struct mm_struct *mm = current->mm;

if (!mm->context.size)
return 0;
if (bytecount > LDT_ENTRY_SIZE*LDT_ENTRIES)
bytecount = LDT_ENTRY_SIZE*LDT_ENTRIES;
if (bytecount > LDT_ENTRY_SIZE * LDT_ENTRIES)
bytecount = LDT_ENTRY_SIZE * LDT_ENTRIES;

mutex_lock(&mm->context.lock);
size = mm->context.size*LDT_ENTRY_SIZE;
size = mm->context.size * LDT_ENTRY_SIZE;
if (size > bytecount)
size = bytecount;

Expand All @@ -143,7 +146,7 @@ static int read_ldt(void __user * ptr, unsigned long bytecount)
goto error_return;
if (size != bytecount) {
/* zero-fill the rest */
if (clear_user(ptr+size, bytecount-size) != 0) {
if (clear_user(ptr + size, bytecount - size) != 0) {
err = -EFAULT;
goto error_return;
}
Expand All @@ -153,13 +156,13 @@ static int read_ldt(void __user * ptr, unsigned long bytecount)
return err;
}

static int read_default_ldt(void __user * ptr, unsigned long bytecount)
static int read_default_ldt(void __user *ptr, unsigned long bytecount)
{
int err;
unsigned long size;

err = 0;
size = 5*sizeof(struct desc_struct);
size = 5 * sizeof(struct desc_struct);
if (size > bytecount)
size = bytecount;

Expand All @@ -170,17 +173,17 @@ static int read_default_ldt(void __user * ptr, unsigned long bytecount)
return err;
}

static int write_ldt(void __user * ptr, unsigned long bytecount, int oldmode)
static int write_ldt(void __user *ptr, unsigned long bytecount, int oldmode)
{
struct mm_struct * mm = current->mm;
struct mm_struct *mm = current->mm;
__u32 entry_1, entry_2;
int error;
struct user_desc ldt_info;

error = -EINVAL;
if (bytecount != sizeof(ldt_info))
goto out;
error = -EFAULT;
error = -EFAULT;
if (copy_from_user(&ldt_info, ptr, sizeof(ldt_info)))
goto out;

Expand All @@ -196,13 +199,14 @@ static int write_ldt(void __user * ptr, unsigned long bytecount, int oldmode)

mutex_lock(&mm->context.lock);
if (ldt_info.entry_number >= mm->context.size) {
error = alloc_ldt(&current->mm->context, ldt_info.entry_number+1, 1);
error = alloc_ldt(&current->mm->context,
ldt_info.entry_number + 1, 1);
if (error < 0)
goto out_unlock;
}

/* Allow LDTs to be cleared by the user. */
if (ldt_info.base_addr == 0 && ldt_info.limit == 0) {
/* Allow LDTs to be cleared by the user. */
if (ldt_info.base_addr == 0 && ldt_info.limit == 0) {
if (oldmode || LDT_empty(&ldt_info)) {
entry_1 = 0;
entry_2 = 0;
Expand All @@ -217,7 +221,8 @@ static int write_ldt(void __user * ptr, unsigned long bytecount, int oldmode)

/* Install the new entry ... */
install:
write_ldt_entry(mm->context.ldt, ldt_info.entry_number, entry_1, entry_2);
write_ldt_entry(mm->context.ldt, ldt_info.entry_number, entry_1,
entry_2);
error = 0;

out_unlock:
Expand All @@ -226,7 +231,8 @@ static int write_ldt(void __user * ptr, unsigned long bytecount, int oldmode)
return error;
}

asmlinkage int sys_modify_ldt(int func, void __user *ptr, unsigned long bytecount)
asmlinkage int sys_modify_ldt(int func, void __user *ptr,
unsigned long bytecount)
{
int ret = -ENOSYS;

Expand Down
69 changes: 36 additions & 33 deletions trunk/arch/x86/kernel/ldt_64.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2,7 +2,7 @@
* Copyright (C) 1992 Krishna Balasubramanian and Linus Torvalds
* Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
* Copyright (C) 2002 Andi Kleen
*
*
* This handles calls from both 32bit and 64bit mode.
*/

Expand All @@ -20,11 +20,11 @@
#include <asm/desc.h>
#include <asm/proto.h>

#ifdef CONFIG_SMP /* avoids "defined but not used" warnig */
#ifdef CONFIG_SMP
static void flush_ldt(void *null)
{
if (current->active_mm)
load_LDT(&current->active_mm->context);
load_LDT(&current->active_mm->context);
}
#endif

Expand All @@ -37,19 +37,20 @@ static int alloc_ldt(mm_context_t *pc, unsigned mincount, int reload)
if (mincount <= (unsigned)pc->size)
return 0;
oldsize = pc->size;
mincount = (mincount+511)&(~511);
if (mincount*LDT_ENTRY_SIZE > PAGE_SIZE)
newldt = vmalloc(mincount*LDT_ENTRY_SIZE);
mincount = (mincount + 511) & (~511);
if (mincount * LDT_ENTRY_SIZE > PAGE_SIZE)
newldt = vmalloc(mincount * LDT_ENTRY_SIZE);
else
newldt = kmalloc(mincount*LDT_ENTRY_SIZE, GFP_KERNEL);
newldt = kmalloc(mincount * LDT_ENTRY_SIZE, GFP_KERNEL);

if (!newldt)
return -ENOMEM;

if (oldsize)
memcpy(newldt, pc->ldt, oldsize*LDT_ENTRY_SIZE);
memcpy(newldt, pc->ldt, oldsize * LDT_ENTRY_SIZE);
oldldt = pc->ldt;
memset(newldt+oldsize*LDT_ENTRY_SIZE, 0, (mincount-oldsize)*LDT_ENTRY_SIZE);
memset(newldt + oldsize * LDT_ENTRY_SIZE, 0,
(mincount - oldsize) * LDT_ENTRY_SIZE);
wmb();
pc->ldt = newldt;
wmb();
Expand All @@ -70,7 +71,7 @@ static int alloc_ldt(mm_context_t *pc, unsigned mincount, int reload)
#endif
}
if (oldsize) {
if (oldsize*LDT_ENTRY_SIZE > PAGE_SIZE)
if (oldsize * LDT_ENTRY_SIZE > PAGE_SIZE)
vfree(oldldt);
else
kfree(oldldt);
Expand All @@ -81,9 +82,10 @@ static int alloc_ldt(mm_context_t *pc, unsigned mincount, int reload)
static inline int copy_ldt(mm_context_t *new, mm_context_t *old)
{
int err = alloc_ldt(new, old->size, 0);

if (err < 0)
return err;
memcpy(new->ldt, old->ldt, old->size*LDT_ENTRY_SIZE);
memcpy(new->ldt, old->ldt, old->size * LDT_ENTRY_SIZE);
return 0;
}

Expand All @@ -93,7 +95,7 @@ static inline int copy_ldt(mm_context_t *new, mm_context_t *old)
*/
int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
{
struct mm_struct * old_mm;
struct mm_struct *old_mm;
int retval = 0;

mutex_init(&mm->context.lock);
Expand All @@ -108,33 +110,32 @@ int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
}

/*
*
* Don't touch the LDT register - we're already in the next thread.
*/
void destroy_context(struct mm_struct *mm)
{
if (mm->context.size) {
if ((unsigned)mm->context.size*LDT_ENTRY_SIZE > PAGE_SIZE)
if ((unsigned)mm->context.size * LDT_ENTRY_SIZE > PAGE_SIZE)
vfree(mm->context.ldt);
else
kfree(mm->context.ldt);
mm->context.size = 0;
}
}

static int read_ldt(void __user * ptr, unsigned long bytecount)
static int read_ldt(void __user *ptr, unsigned long bytecount)
{
int err;
unsigned long size;
struct mm_struct * mm = current->mm;
struct mm_struct *mm = current->mm;

if (!mm->context.size)
return 0;
if (bytecount > LDT_ENTRY_SIZE*LDT_ENTRIES)
bytecount = LDT_ENTRY_SIZE*LDT_ENTRIES;
if (bytecount > LDT_ENTRY_SIZE * LDT_ENTRIES)
bytecount = LDT_ENTRY_SIZE * LDT_ENTRIES;

mutex_lock(&mm->context.lock);
size = mm->context.size*LDT_ENTRY_SIZE;
size = mm->context.size * LDT_ENTRY_SIZE;
if (size > bytecount)
size = bytecount;

Expand All @@ -146,7 +147,7 @@ static int read_ldt(void __user * ptr, unsigned long bytecount)
goto error_return;
if (size != bytecount) {
/* zero-fill the rest */
if (clear_user(ptr+size, bytecount-size) != 0) {
if (clear_user(ptr + size, bytecount - size) != 0) {
err = -EFAULT;
goto error_return;
}
Expand All @@ -156,21 +157,21 @@ static int read_ldt(void __user * ptr, unsigned long bytecount)
return err;
}

static int read_default_ldt(void __user * ptr, unsigned long bytecount)
static int read_default_ldt(void __user *ptr, unsigned long bytecount)
{
/* Arbitrary number */
/* Arbitrary number */
/* x86-64 default LDT is all zeros */
if (bytecount > 128)
bytecount = 128;
if (bytecount > 128)
bytecount = 128;
if (clear_user(ptr, bytecount))
return -EFAULT;
return bytecount;
return bytecount;
}

static int write_ldt(void __user * ptr, unsigned long bytecount, int oldmode)
static int write_ldt(void __user *ptr, unsigned long bytecount, int oldmode)
{
struct task_struct *me = current;
struct mm_struct * mm = me->mm;
struct mm_struct *mm = me->mm;
__u32 entry_1, entry_2, *lp;
int error;
struct user_desc ldt_info;
Expand All @@ -179,7 +180,7 @@ static int write_ldt(void __user * ptr, unsigned long bytecount, int oldmode)

if (bytecount != sizeof(ldt_info))
goto out;
error = -EFAULT;
error = -EFAULT;
if (copy_from_user(&ldt_info, ptr, bytecount))
goto out;

Expand All @@ -195,15 +196,16 @@ static int write_ldt(void __user * ptr, unsigned long bytecount, int oldmode)

mutex_lock(&mm->context.lock);
if (ldt_info.entry_number >= (unsigned)mm->context.size) {
error = alloc_ldt(&current->mm->context, ldt_info.entry_number+1, 1);
error = alloc_ldt(&current->mm->context,
ldt_info.entry_number + 1, 1);
if (error < 0)
goto out_unlock;
}

lp = (__u32 *) ((ldt_info.entry_number << 3) + (char *) mm->context.ldt);
lp = (__u32 *)((ldt_info.entry_number << 3) + (char *)mm->context.ldt);

/* Allow LDTs to be cleared by the user. */
if (ldt_info.base_addr == 0 && ldt_info.limit == 0) {
/* Allow LDTs to be cleared by the user. */
if (ldt_info.base_addr == 0 && ldt_info.limit == 0) {
if (oldmode || LDT_empty(&ldt_info)) {
entry_1 = 0;
entry_2 = 0;
Expand All @@ -228,7 +230,8 @@ static int write_ldt(void __user * ptr, unsigned long bytecount, int oldmode)
return error;
}

asmlinkage int sys_modify_ldt(int func, void __user *ptr, unsigned long bytecount)
asmlinkage int sys_modify_ldt(int func, void __user *ptr,
unsigned long bytecount)
{
int ret = -ENOSYS;

Expand Down

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