diff options
Diffstat (limited to 'ANDROID_3.4.5/arch/s390/lib/uaccess_pt.c')
-rw-r--r-- | ANDROID_3.4.5/arch/s390/lib/uaccess_pt.c | 406 |
1 files changed, 0 insertions, 406 deletions
diff --git a/ANDROID_3.4.5/arch/s390/lib/uaccess_pt.c b/ANDROID_3.4.5/arch/s390/lib/uaccess_pt.c deleted file mode 100644 index 342ae35a..00000000 --- a/ANDROID_3.4.5/arch/s390/lib/uaccess_pt.c +++ /dev/null @@ -1,406 +0,0 @@ -/* - * arch/s390/lib/uaccess_pt.c - * - * User access functions based on page table walks for enhanced - * system layout without hardware support. - * - * Copyright IBM Corp. 2006 - * Author(s): Gerald Schaefer (gerald.schaefer@de.ibm.com) - */ - -#include <linux/errno.h> -#include <linux/hardirq.h> -#include <linux/mm.h> -#include <asm/uaccess.h> -#include <asm/futex.h> -#include "uaccess.h" - -static inline pte_t *follow_table(struct mm_struct *mm, unsigned long addr) -{ - pgd_t *pgd; - pud_t *pud; - pmd_t *pmd; - - pgd = pgd_offset(mm, addr); - if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd))) - return (pte_t *) 0x3a; - - pud = pud_offset(pgd, addr); - if (pud_none(*pud) || unlikely(pud_bad(*pud))) - return (pte_t *) 0x3b; - - pmd = pmd_offset(pud, addr); - if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd))) - return (pte_t *) 0x10; - - return pte_offset_map(pmd, addr); -} - -static __always_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; - pte_t *pte; - void *from, *to; - - done = 0; -retry: - spin_lock(&mm->page_table_lock); - do { - pte = follow_table(mm, uaddr); - if ((unsigned long) pte < 0x1000) - goto fault; - if (!pte_present(*pte)) { - pte = (pte_t *) 0x11; - goto fault; - } else if (write_user && !pte_write(*pte)) { - pte = (pte_t *) 0x04; - goto fault; - } - - pfn = pte_pfn(*pte); - 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); - spin_unlock(&mm->page_table_lock); - return n - done; -fault: - spin_unlock(&mm->page_table_lock); - if (__handle_fault(uaddr, (unsigned long) pte, write_user)) - return n - done; - goto retry; -} - -/* - * Do DAT for user address by page table walk, return kernel address. - * This function needs to be called with current->mm->page_table_lock held. - */ -static __always_inline unsigned long __dat_user_addr(unsigned long uaddr) -{ - struct mm_struct *mm = current->mm; - unsigned long pfn; - pte_t *pte; - int rc; - -retry: - pte = follow_table(mm, uaddr); - if ((unsigned long) pte < 0x1000) - goto fault; - if (!pte_present(*pte)) { - pte = (pte_t *) 0x11; - goto fault; - } - - pfn = pte_pfn(*pte); - return (pfn << PAGE_SHIFT) + (uaddr & (PAGE_SIZE - 1)); -fault: - spin_unlock(&mm->page_table_lock); - rc = __handle_fault(uaddr, (unsigned long) pte, 0); - spin_lock(&mm->page_table_lock); - if (!rc) - goto retry; - return 0; -} - -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); -} - -static size_t clear_user_pt(size_t n, void __user *to) -{ - long done, size, ret; - - if (segment_eq(get_fs(), KERNEL_DS)) { - memset((void __kernel __force *) to, 0, n); - return 0; - } - done = 0; - do { - if (n - done > PAGE_SIZE) - size = PAGE_SIZE; - else - size = n - done; - ret = __user_copy_pt((unsigned long) to + done, - &empty_zero_page, size, 1); - done += size; - if (ret) - return ret + n - done; - } while (done < n); - return 0; -} - -static size_t strnlen_user_pt(size_t count, const char __user *src) -{ - char *addr; - unsigned long uaddr = (unsigned long) src; - struct mm_struct *mm = current->mm; - unsigned long offset, pfn, done, len; - pte_t *pte; - size_t len_str; - - if (segment_eq(get_fs(), KERNEL_DS)) - return strnlen((const char __kernel __force *) src, count) + 1; - done = 0; -retry: - spin_lock(&mm->page_table_lock); - do { - pte = follow_table(mm, uaddr); - if ((unsigned long) pte < 0x1000) - goto fault; - if (!pte_present(*pte)) { - pte = (pte_t *) 0x11; - goto fault; - } - - pfn = pte_pfn(*pte); - offset = uaddr & (PAGE_SIZE-1); - addr = (char *)(pfn << PAGE_SHIFT) + offset; - len = min(count - done, PAGE_SIZE - offset); - len_str = strnlen(addr, len); - done += len_str; - uaddr += len_str; - } while ((len_str == len) && (done < count)); - spin_unlock(&mm->page_table_lock); - return done + 1; -fault: - spin_unlock(&mm->page_table_lock); - if (__handle_fault(uaddr, (unsigned long) pte, 0)) - return 0; - goto retry; -} - -static size_t strncpy_from_user_pt(size_t count, const char __user *src, - char *dst) -{ - size_t n = strnlen_user_pt(count, src); - - if (!n) - return -EFAULT; - if (n > count) - n = count; - if (segment_eq(get_fs(), KERNEL_DS)) { - memcpy(dst, (const char __kernel __force *) src, n); - if (dst[n-1] == '\0') - return n-1; - else - return n; - } - if (__user_copy_pt((unsigned long) src, dst, n, 0)) - return -EFAULT; - if (dst[n-1] == '\0') - return n-1; - else - return n; -} - -static size_t copy_in_user_pt(size_t n, void __user *to, - const void __user *from) -{ - struct mm_struct *mm = current->mm; - unsigned long offset_from, offset_to, offset_max, pfn_from, pfn_to, - uaddr, done, size, error_code; - unsigned long uaddr_from = (unsigned long) from; - unsigned long uaddr_to = (unsigned long) to; - pte_t *pte_from, *pte_to; - int write_user; - - if (segment_eq(get_fs(), KERNEL_DS)) { - memcpy((void __force *) to, (void __force *) from, n); - return 0; - } - done = 0; -retry: - spin_lock(&mm->page_table_lock); - do { - write_user = 0; - uaddr = uaddr_from; - pte_from = follow_table(mm, uaddr_from); - error_code = (unsigned long) pte_from; - if (error_code < 0x1000) - goto fault; - if (!pte_present(*pte_from)) { - error_code = 0x11; - goto fault; - } - - write_user = 1; - uaddr = uaddr_to; - pte_to = follow_table(mm, uaddr_to); - error_code = (unsigned long) pte_to; - if (error_code < 0x1000) - goto fault; - if (!pte_present(*pte_to)) { - error_code = 0x11; - goto fault; - } else if (!pte_write(*pte_to)) { - error_code = 0x04; - goto fault; - } - - pfn_from = pte_pfn(*pte_from); - pfn_to = pte_pfn(*pte_to); - offset_from = uaddr_from & (PAGE_SIZE-1); - offset_to = uaddr_from & (PAGE_SIZE-1); - offset_max = max(offset_from, offset_to); - size = min(n - done, PAGE_SIZE - offset_max); - - memcpy((void *)(pfn_to << PAGE_SHIFT) + offset_to, - (void *)(pfn_from << PAGE_SHIFT) + offset_from, size); - done += size; - uaddr_from += size; - uaddr_to += size; - } while (done < n); - spin_unlock(&mm->page_table_lock); - return n - done; -fault: - spin_unlock(&mm->page_table_lock); - if (__handle_fault(uaddr, error_code, write_user)) - return n - done; - goto retry; -} - -#define __futex_atomic_op(insn, ret, oldval, newval, uaddr, oparg) \ - asm volatile("0: l %1,0(%6)\n" \ - "1: " insn \ - "2: cs %1,%2,0(%6)\n" \ - "3: jl 1b\n" \ - " lhi %0,0\n" \ - "4:\n" \ - EX_TABLE(0b,4b) EX_TABLE(2b,4b) EX_TABLE(3b,4b) \ - : "=d" (ret), "=&d" (oldval), "=&d" (newval), \ - "=m" (*uaddr) \ - : "0" (-EFAULT), "d" (oparg), "a" (uaddr), \ - "m" (*uaddr) : "cc" ); - -static int __futex_atomic_op_pt(int op, u32 __user *uaddr, int oparg, int *old) -{ - int oldval = 0, newval, ret; - - switch (op) { - case FUTEX_OP_SET: - __futex_atomic_op("lr %2,%5\n", - ret, oldval, newval, uaddr, oparg); - break; - case FUTEX_OP_ADD: - __futex_atomic_op("lr %2,%1\nar %2,%5\n", - ret, oldval, newval, uaddr, oparg); - break; - case FUTEX_OP_OR: - __futex_atomic_op("lr %2,%1\nor %2,%5\n", - ret, oldval, newval, uaddr, oparg); - break; - case FUTEX_OP_ANDN: - __futex_atomic_op("lr %2,%1\nnr %2,%5\n", - ret, oldval, newval, uaddr, oparg); - break; - case FUTEX_OP_XOR: - __futex_atomic_op("lr %2,%1\nxr %2,%5\n", - ret, oldval, newval, uaddr, oparg); - break; - default: - ret = -ENOSYS; - } - if (ret == 0) - *old = oldval; - return ret; -} - -int futex_atomic_op_pt(int op, u32 __user *uaddr, int oparg, int *old) -{ - int ret; - - if (segment_eq(get_fs(), KERNEL_DS)) - return __futex_atomic_op_pt(op, uaddr, oparg, old); - spin_lock(¤t->mm->page_table_lock); - uaddr = (u32 __force __user *) - __dat_user_addr((__force unsigned long) uaddr); - if (!uaddr) { - spin_unlock(¤t->mm->page_table_lock); - return -EFAULT; - } - get_page(virt_to_page(uaddr)); - spin_unlock(¤t->mm->page_table_lock); - ret = __futex_atomic_op_pt(op, uaddr, oparg, old); - put_page(virt_to_page(uaddr)); - return ret; -} - -static int __futex_atomic_cmpxchg_pt(u32 *uval, u32 __user *uaddr, - u32 oldval, u32 newval) -{ - int ret; - - asm volatile("0: cs %1,%4,0(%5)\n" - "1: la %0,0\n" - "2:\n" - EX_TABLE(0b,2b) EX_TABLE(1b,2b) - : "=d" (ret), "+d" (oldval), "=m" (*uaddr) - : "0" (-EFAULT), "d" (newval), "a" (uaddr), "m" (*uaddr) - : "cc", "memory" ); - *uval = oldval; - return ret; -} - -int futex_atomic_cmpxchg_pt(u32 *uval, u32 __user *uaddr, - u32 oldval, u32 newval) -{ - int ret; - - if (segment_eq(get_fs(), KERNEL_DS)) - return __futex_atomic_cmpxchg_pt(uval, uaddr, oldval, newval); - spin_lock(¤t->mm->page_table_lock); - uaddr = (u32 __force __user *) - __dat_user_addr((__force unsigned long) uaddr); - if (!uaddr) { - spin_unlock(¤t->mm->page_table_lock); - return -EFAULT; - } - get_page(virt_to_page(uaddr)); - spin_unlock(¤t->mm->page_table_lock); - ret = __futex_atomic_cmpxchg_pt(uval, uaddr, oldval, newval); - put_page(virt_to_page(uaddr)); - return ret; -} - -struct uaccess_ops uaccess_pt = { - .copy_from_user = copy_from_user_pt, - .copy_from_user_small = copy_from_user_pt, - .copy_to_user = copy_to_user_pt, - .copy_to_user_small = copy_to_user_pt, - .copy_in_user = copy_in_user_pt, - .clear_user = clear_user_pt, - .strnlen_user = strnlen_user_pt, - .strncpy_from_user = strncpy_from_user_pt, - .futex_atomic_op = futex_atomic_op_pt, - .futex_atomic_cmpxchg = futex_atomic_cmpxchg_pt, -}; |