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-rw-r--r--arch/s390/mm/Makefile2
-rw-r--r--arch/s390/mm/fault.c5
-rw-r--r--arch/s390/mm/maccess.c61
-rw-r--r--arch/s390/mm/mmap.c11
-rw-r--r--arch/s390/mm/pgtable.c35
5 files changed, 102 insertions, 12 deletions
diff --git a/arch/s390/mm/Makefile b/arch/s390/mm/Makefile
index 2a745813454..db05661ac89 100644
--- a/arch/s390/mm/Makefile
+++ b/arch/s390/mm/Makefile
@@ -2,7 +2,7 @@
# Makefile for the linux s390-specific parts of the memory manager.
#
-obj-y := init.o fault.o extmem.o mmap.o vmem.o pgtable.o
+obj-y := init.o fault.o extmem.o mmap.o vmem.o pgtable.o maccess.o
obj-$(CONFIG_CMM) += cmm.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
obj-$(CONFIG_PAGE_STATES) += page-states.o
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 833e8366c35..74eb26bf197 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -19,6 +19,7 @@
#include <linux/ptrace.h>
#include <linux/mman.h>
#include <linux/mm.h>
+#include <linux/compat.h>
#include <linux/smp.h>
#include <linux/kdebug.h>
#include <linux/smp_lock.h>
@@ -239,7 +240,7 @@ static int signal_return(struct mm_struct *mm, struct pt_regs *regs,
up_read(&mm->mmap_sem);
clear_tsk_thread_flag(current, TIF_SINGLE_STEP);
#ifdef CONFIG_COMPAT
- compat = test_tsk_thread_flag(current, TIF_31BIT);
+ compat = is_compat_task();
if (compat && instruction == 0x0a77)
sys32_sigreturn();
else if (compat && instruction == 0x0aad)
@@ -351,7 +352,7 @@ good_area:
* make sure we exit gracefully rather than endlessly redo
* the fault.
*/
- fault = handle_mm_fault(mm, vma, address, write);
+ fault = handle_mm_fault(mm, vma, address, write ? FAULT_FLAG_WRITE : 0);
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM) {
up_read(&mm->mmap_sem);
diff --git a/arch/s390/mm/maccess.c b/arch/s390/mm/maccess.c
new file mode 100644
index 00000000000..81756271dc4
--- /dev/null
+++ b/arch/s390/mm/maccess.c
@@ -0,0 +1,61 @@
+/*
+ * Access kernel memory without faulting -- s390 specific implementation.
+ *
+ * Copyright IBM Corp. 2009
+ *
+ * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
+ *
+ */
+
+#include <linux/uaccess.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <asm/system.h>
+
+/*
+ * This function writes to kernel memory bypassing DAT and possible
+ * write protection. It copies one to four bytes from src to dst
+ * using the stura instruction.
+ * Returns the number of bytes copied or -EFAULT.
+ */
+static long probe_kernel_write_odd(void *dst, void *src, size_t size)
+{
+ unsigned long count, aligned;
+ int offset, mask;
+ int rc = -EFAULT;
+
+ aligned = (unsigned long) dst & ~3UL;
+ offset = (unsigned long) dst & 3;
+ count = min_t(unsigned long, 4 - offset, size);
+ mask = (0xf << (4 - count)) & 0xf;
+ mask >>= offset;
+ asm volatile(
+ " bras 1,0f\n"
+ " icm 0,0,0(%3)\n"
+ "0: l 0,0(%1)\n"
+ " lra %1,0(%1)\n"
+ "1: ex %2,0(1)\n"
+ "2: stura 0,%1\n"
+ " la %0,0\n"
+ "3:\n"
+ EX_TABLE(0b,3b) EX_TABLE(1b,3b) EX_TABLE(2b,3b)
+ : "+d" (rc), "+a" (aligned)
+ : "a" (mask), "a" (src) : "cc", "memory", "0", "1");
+ return rc ? rc : count;
+}
+
+long probe_kernel_write(void *dst, void *src, size_t size)
+{
+ long copied = 0;
+
+ while (size) {
+ copied = probe_kernel_write_odd(dst, src, size);
+ if (copied < 0)
+ break;
+ dst += copied;
+ src += copied;
+ size -= copied;
+ }
+ return copied < 0 ? -EFAULT : 0;
+}
diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
index e008d236cc1..f4558ccf02b 100644
--- a/arch/s390/mm/mmap.c
+++ b/arch/s390/mm/mmap.c
@@ -28,6 +28,7 @@
#include <linux/mm.h>
#include <linux/module.h>
#include <asm/pgalloc.h>
+#include <asm/compat.h>
/*
* Top of mmap area (just below the process stack).
@@ -55,7 +56,7 @@ static inline int mmap_is_legacy(void)
/*
* Force standard allocation for 64 bit programs.
*/
- if (!test_thread_flag(TIF_31BIT))
+ if (!is_compat_task())
return 1;
#endif
return sysctl_legacy_va_layout ||
@@ -91,7 +92,7 @@ EXPORT_SYMBOL_GPL(arch_pick_mmap_layout);
int s390_mmap_check(unsigned long addr, unsigned long len)
{
- if (!test_thread_flag(TIF_31BIT) &&
+ if (!is_compat_task() &&
len >= TASK_SIZE && TASK_SIZE < (1UL << 53))
return crst_table_upgrade(current->mm, 1UL << 53);
return 0;
@@ -108,8 +109,7 @@ s390_get_unmapped_area(struct file *filp, unsigned long addr,
area = arch_get_unmapped_area(filp, addr, len, pgoff, flags);
if (!(area & ~PAGE_MASK))
return area;
- if (area == -ENOMEM &&
- !test_thread_flag(TIF_31BIT) && TASK_SIZE < (1UL << 53)) {
+ if (area == -ENOMEM && !is_compat_task() && TASK_SIZE < (1UL << 53)) {
/* Upgrade the page table to 4 levels and retry. */
rc = crst_table_upgrade(mm, 1UL << 53);
if (rc)
@@ -131,8 +131,7 @@ s390_get_unmapped_area_topdown(struct file *filp, const unsigned long addr,
area = arch_get_unmapped_area_topdown(filp, addr, len, pgoff, flags);
if (!(area & ~PAGE_MASK))
return area;
- if (area == -ENOMEM &&
- !test_thread_flag(TIF_31BIT) && TASK_SIZE < (1UL << 53)) {
+ if (area == -ENOMEM && !is_compat_task() && TASK_SIZE < (1UL << 53)) {
/* Upgrade the page table to 4 levels and retry. */
rc = crst_table_upgrade(mm, 1UL << 53);
if (rc)
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index be6c1cf4ad5..56566720798 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -1,7 +1,5 @@
/*
- * arch/s390/mm/pgtable.c
- *
- * Copyright IBM Corp. 2007
+ * Copyright IBM Corp. 2007,2009
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
*/
@@ -53,6 +51,18 @@ void clear_table_pgstes(unsigned long *table)
#endif
+unsigned long VMALLOC_START = VMALLOC_END - VMALLOC_SIZE;
+EXPORT_SYMBOL(VMALLOC_START);
+
+static int __init parse_vmalloc(char *arg)
+{
+ if (!arg)
+ return -EINVAL;
+ VMALLOC_START = (VMALLOC_END - memparse(arg, &arg)) & PAGE_MASK;
+ return 0;
+}
+early_param("vmalloc", parse_vmalloc);
+
unsigned long *crst_table_alloc(struct mm_struct *mm, int noexec)
{
struct page *page = alloc_pages(GFP_KERNEL, ALLOC_ORDER);
@@ -303,3 +313,22 @@ int s390_enable_sie(void)
return 0;
}
EXPORT_SYMBOL_GPL(s390_enable_sie);
+
+#ifdef CONFIG_DEBUG_PAGEALLOC
+#ifdef CONFIG_HIBERNATION
+bool kernel_page_present(struct page *page)
+{
+ unsigned long addr;
+ int cc;
+
+ addr = page_to_phys(page);
+ asm("lra %1,0(%1)\n"
+ "ipm %0\n"
+ "srl %0,28"
+ :"=d"(cc),"+a"(addr)::"cc");
+ return cc == 0;
+}
+
+#endif /* CONFIG_HIBERNATION */
+#endif /* CONFIG_DEBUG_PAGEALLOC */
+