diff options
| -rw-r--r-- | arch/s390/lib/Makefile | 2 | ||||
| -rw-r--r-- | arch/s390/lib/uaccess_mvcos.c | 27 | ||||
| -rw-r--r-- | arch/s390/lib/uaccess_pt.c | 153 | ||||
| -rw-r--r-- | arch/s390/lib/uaccess_std.c | 67 |
4 files changed, 190 insertions, 59 deletions
diff --git a/arch/s390/lib/Makefile b/arch/s390/lib/Makefile index b0cfa6c4883d..b5f94cf3bde8 100644 --- a/arch/s390/lib/Makefile +++ b/arch/s390/lib/Makefile @@ -4,7 +4,7 @@ EXTRA_AFLAGS := -traditional -lib-y += delay.o string.o uaccess_std.o +lib-y += delay.o string.o uaccess_std.o uaccess_pt.o lib-$(CONFIG_32BIT) += div64.o lib-$(CONFIG_64BIT) += uaccess_mvcos.o lib-$(CONFIG_SMP) += spinlock.o diff --git a/arch/s390/lib/uaccess_mvcos.c b/arch/s390/lib/uaccess_mvcos.c index 121b2935a422..f9a23d57eb79 100644 --- a/arch/s390/lib/uaccess_mvcos.c +++ b/arch/s390/lib/uaccess_mvcos.c @@ -27,6 +27,9 @@ #define SLR "slgr" #endif +extern size_t copy_from_user_std(size_t, const void __user *, void *); +extern size_t copy_to_user_std(size_t, void __user *, const void *); + size_t copy_from_user_mvcos(size_t size, const void __user *ptr, void *x) { register unsigned long reg0 asm("0") = 0x81UL; @@ -66,6 +69,13 @@ size_t copy_from_user_mvcos(size_t size, const void __user *ptr, void *x) return size; } +size_t copy_from_user_mvcos_check(size_t size, const void __user *ptr, void *x) +{ + if (size <= 256) + return copy_from_user_std(size, ptr, x); + return copy_from_user_mvcos(size, ptr, x); +} + size_t copy_to_user_mvcos(size_t size, void __user *ptr, const void *x) { register unsigned long reg0 asm("0") = 0x810000UL; @@ -95,6 +105,13 @@ size_t copy_to_user_mvcos(size_t size, void __user *ptr, const void *x) return size; } +size_t copy_to_user_mvcos_check(size_t size, void __user *ptr, const void *x) +{ + if (size <= 256) + return copy_to_user_std(size, ptr, x); + return copy_to_user_mvcos(size, ptr, x); +} + size_t copy_in_user_mvcos(size_t size, void __user *to, const void __user *from) { register unsigned long reg0 asm("0") = 0x810081UL; @@ -145,18 +162,16 @@ size_t clear_user_mvcos(size_t size, void __user *to) return size; } -extern size_t copy_from_user_std_small(size_t, const void __user *, void *); -extern size_t copy_to_user_std_small(size_t, void __user *, const void *); extern size_t strnlen_user_std(size_t, const char __user *); extern size_t strncpy_from_user_std(size_t, const char __user *, char *); extern int futex_atomic_op(int, int __user *, int, int *); extern int futex_atomic_cmpxchg(int __user *, int, int); struct uaccess_ops uaccess_mvcos = { - .copy_from_user = copy_from_user_mvcos, - .copy_from_user_small = copy_from_user_std_small, - .copy_to_user = copy_to_user_mvcos, - .copy_to_user_small = copy_to_user_std_small, + .copy_from_user = copy_from_user_mvcos_check, + .copy_from_user_small = copy_from_user_std, + .copy_to_user = copy_to_user_mvcos_check, + .copy_to_user_small = copy_to_user_std, .copy_in_user = copy_in_user_mvcos, .clear_user = clear_user_mvcos, .strnlen_user = strnlen_user_std, diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c new file mode 100644 index 000000000000..8741bdc09299 --- /dev/null +++ b/arch/s390/lib/uaccess_pt.c @@ -0,0 +1,153 @@ +/* + * arch/s390/lib/uaccess_pt.c + * + * User access functions based on page table walks. + * + * Copyright IBM Corp. 2006 + * Author(s): Gerald Schaefer (gerald.schaefer@de.ibm.com) + */ + +#include <linux/errno.h> +#include <asm/uaccess.h> +#include <linux/mm.h> +#include <asm/futex.h> + +static inline int __handle_fault(struct mm_struct *mm, unsigned long address, + int write_access) +{ + struct vm_area_struct *vma; + int ret = -EFAULT; + + down_read(&mm->mmap_sem); + vma = find_vma(mm, address); + if (unlikely(!vma)) + goto out; + if (unlikely(vma->vm_start > address)) { + if (!(vma->vm_flags & VM_GROWSDOWN)) + goto out; + if (expand_stack(vma, address)) + goto out; + } + + if (!write_access) { + /* page not present, check vm flags */ + if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE))) + goto out; + } else { + if (!(vma->vm_flags & VM_WRITE)) + goto out; + } + +survive: + switch (handle_mm_fault(mm, vma, address, write_access)) { + case VM_FAULT_MINOR: + current->min_flt++; + break; + case VM_FAULT_MAJOR: + current->maj_flt++; + break; + case VM_FAULT_SIGBUS: + goto out_sigbus; + case VM_FAULT_OOM: + goto out_of_memory; + default: + BUG(); + } + ret = 0; +out: + up_read(&mm->mmap_sem); + return ret; + +out_of_memory: + up_read(&mm->mmap_sem); + if (current->pid == 1) { + yield(); + goto survive; + } + printk("VM: killing process %s\n", current->comm); + return ret; + +out_sigbus: + up_read(&mm->mmap_sem); + current->thread.prot_addr = address; + current->thread.trap_no = 0x11; + force_sig(SIGBUS, current); + return ret; +} + +static inline size_t __user_copy_pt(unsigned long uaddr, void *kptr, + size_t n, int write_user) +{ + struct mm_struct *mm = current->mm; + unsigned long offset, pfn, done, size; + pgd_t *pgd; + pmd_t *pmd; + pte_t *pte; + void *from, *to; + + done = 0; +retry: + spin_lock(&mm->page_table_lock); + do { + pgd = pgd_offset(mm, uaddr); + if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd))) + goto fault; + + pmd = pmd_offset(pgd, uaddr); + if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd))) + goto fault; + + pte = pte_offset_map(pmd, uaddr); + if (!pte || !pte_present(*pte) || + (write_user && !pte_write(*pte))) + goto fault; + + pfn = pte_pfn(*pte); + if (!pfn_valid(pfn)) + goto out; + + offset = uaddr & (PAGE_SIZE - 1); + size = min(n - done, PAGE_SIZE - offset); + if (write_user) { + to = (void *)((pfn << PAGE_SHIFT) + offset); + from = kptr + done; + } else { + from = (void *)((pfn << PAGE_SHIFT) + offset); + to = kptr + done; + } + memcpy(to, from, size); + done += size; + uaddr += size; + } while (done < n); +out: + spin_unlock(&mm->page_table_lock); + return n - done; +fault: + spin_unlock(&mm->page_table_lock); + if (__handle_fault(mm, uaddr, write_user)) + return n - done; + goto retry; +} + +size_t copy_from_user_pt(size_t n, const void __user *from, void *to) +{ + size_t rc; + + if (segment_eq(get_fs(), KERNEL_DS)) { + memcpy(to, (void __kernel __force *) from, n); + return 0; + } + rc = __user_copy_pt((unsigned long) from, to, n, 0); + if (unlikely(rc)) + memset(to + n - rc, 0, rc); + return rc; +} + +size_t copy_to_user_pt(size_t n, void __user *to, const void *from) +{ + if (segment_eq(get_fs(), KERNEL_DS)) { + memcpy((void __kernel __force *) to, from, n); + return 0; + } + return __user_copy_pt((unsigned long) to, (void *) from, n, 1); +} diff --git a/arch/s390/lib/uaccess_std.c b/arch/s390/lib/uaccess_std.c index f44f0078b354..2d549ed2e113 100644 --- a/arch/s390/lib/uaccess_std.c +++ b/arch/s390/lib/uaccess_std.c @@ -28,6 +28,9 @@ #define SLR "slgr" #endif +extern size_t copy_from_user_pt(size_t n, const void __user *from, void *to); +extern size_t copy_to_user_pt(size_t n, void __user *to, const void *from); + size_t copy_from_user_std(size_t size, const void __user *ptr, void *x) { unsigned long tmp1, tmp2; @@ -69,34 +72,11 @@ size_t copy_from_user_std(size_t size, const void __user *ptr, void *x) return size; } -size_t copy_from_user_std_small(size_t size, const void __user *ptr, void *x) +size_t copy_from_user_std_check(size_t size, const void __user *ptr, void *x) { - unsigned long tmp1, tmp2; - - tmp1 = 0UL; - asm volatile( - "0: mvcp 0(%0,%2),0(%1),%3\n" - " "SLR" %0,%0\n" - " j 5f\n" - "1: la %4,255(%1)\n" /* %4 = ptr + 255 */ - " "LHI" %3,-4096\n" - " nr %4,%3\n" /* %4 = (ptr + 255) & -4096 */ - " "SLR" %4,%1\n" - " "CLR" %0,%4\n" /* copy crosses next page boundary? */ - " jnh 5f\n" - "2: mvcp 0(%4,%2),0(%1),%3\n" - " "SLR" %0,%4\n" - " "ALR" %2,%4\n" - "3:"LHI" %4,-1\n" - " "ALR" %4,%0\n" /* copy remaining size, subtract 1 */ - " bras %3,4f\n" - " xc 0(1,%2),0(%2)\n" - "4: ex %4,0(%3)\n" - "5:\n" - EX_TABLE(0b,1b) EX_TABLE(2b,3b) - : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2) - : : "cc", "memory"); - return size; + if (size <= 1024) + return copy_from_user_std(size, ptr, x); + return copy_from_user_pt(size, ptr, x); } size_t copy_to_user_std(size_t size, void __user *ptr, const void *x) @@ -130,28 +110,11 @@ size_t copy_to_user_std(size_t size, void __user *ptr, const void *x) return size; } -size_t copy_to_user_std_small(size_t size, void __user *ptr, const void *x) +size_t copy_to_user_std_check(size_t size, void __user *ptr, const void *x) { - unsigned long tmp1, tmp2; - - tmp1 = 0UL; - asm volatile( - "0: mvcs 0(%0,%1),0(%2),%3\n" - " "SLR" %0,%0\n" - " j 3f\n" - "1: la %4,255(%1)\n" /* ptr + 255 */ - " "LHI" %3,-4096\n" - " nr %4,%3\n" /* (ptr + 255) & -4096UL */ - " "SLR" %4,%1\n" - " "CLR" %0,%4\n" /* copy crosses next page boundary? */ - " jnh 3f\n" - "2: mvcs 0(%4,%1),0(%2),%3\n" - " "SLR" %0,%4\n" - "3:\n" - EX_TABLE(0b,1b) EX_TABLE(2b,3b) - : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2) - : : "cc", "memory"); - return size; + if (size <= 1024) + return copy_to_user_std(size, ptr, x); + return copy_to_user_pt(size, ptr, x); } size_t copy_in_user_std(size_t size, void __user *to, const void __user *from) @@ -343,10 +306,10 @@ int futex_atomic_cmpxchg(int __user *uaddr, int oldval, int newval) } struct uaccess_ops uaccess_std = { - .copy_from_user = copy_from_user_std, - .copy_from_user_small = copy_from_user_std_small, - .copy_to_user = copy_to_user_std, - .copy_to_user_small = copy_to_user_std_small, + .copy_from_user = copy_from_user_std_check, + .copy_from_user_small = copy_from_user_std, + .copy_to_user = copy_to_user_std_check, + .copy_to_user_small = copy_to_user_std, .copy_in_user = copy_in_user_std, .clear_user = clear_user_std, .strnlen_user = strnlen_user_std, |