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Diffstat (limited to 'ANDROID_3.4.5/arch/x86/lib/usercopy.c')
-rw-r--r--ANDROID_3.4.5/arch/x86/lib/usercopy.c146
1 files changed, 0 insertions, 146 deletions
diff --git a/ANDROID_3.4.5/arch/x86/lib/usercopy.c b/ANDROID_3.4.5/arch/x86/lib/usercopy.c
deleted file mode 100644
index d6ae30bb..00000000
--- a/ANDROID_3.4.5/arch/x86/lib/usercopy.c
+++ /dev/null
@@ -1,146 +0,0 @@
-/*
- * User address space access functions.
- *
- * For licencing details see kernel-base/COPYING
- */
-
-#include <linux/highmem.h>
-#include <linux/module.h>
-
-#include <asm/word-at-a-time.h>
-
-/*
- * best effort, GUP based copy_from_user() that is NMI-safe
- */
-unsigned long
-copy_from_user_nmi(void *to, const void __user *from, unsigned long n)
-{
- unsigned long offset, addr = (unsigned long)from;
- unsigned long size, len = 0;
- struct page *page;
- void *map;
- int ret;
-
- do {
- ret = __get_user_pages_fast(addr, 1, 0, &page);
- if (!ret)
- break;
-
- offset = addr & (PAGE_SIZE - 1);
- size = min(PAGE_SIZE - offset, n - len);
-
- map = kmap_atomic(page);
- memcpy(to, map+offset, size);
- kunmap_atomic(map);
- put_page(page);
-
- len += size;
- to += size;
- addr += size;
-
- } while (len < n);
-
- return len;
-}
-EXPORT_SYMBOL_GPL(copy_from_user_nmi);
-
-static inline unsigned long count_bytes(unsigned long mask)
-{
- mask = (mask - 1) & ~mask;
- mask >>= 7;
- return count_masked_bytes(mask);
-}
-
-/*
- * Do a strncpy, return length of string without final '\0'.
- * 'count' is the user-supplied count (return 'count' if we
- * hit it), 'max' is the address space maximum (and we return
- * -EFAULT if we hit it).
- */
-static inline long do_strncpy_from_user(char *dst, const char __user *src, long count, unsigned long max)
-{
- long res = 0;
-
- /*
- * Truncate 'max' to the user-specified limit, so that
- * we only have one limit we need to check in the loop
- */
- if (max > count)
- max = count;
-
- while (max >= sizeof(unsigned long)) {
- unsigned long c;
-
- /* Fall back to byte-at-a-time if we get a page fault */
- if (unlikely(__get_user(c,(unsigned long __user *)(src+res))))
- break;
- /* This can write a few bytes past the NUL character, but that's ok */
- *(unsigned long *)(dst+res) = c;
- c = has_zero(c);
- if (c)
- return res + count_bytes(c);
- res += sizeof(unsigned long);
- max -= sizeof(unsigned long);
- }
-
- while (max) {
- char c;
-
- if (unlikely(__get_user(c,src+res)))
- return -EFAULT;
- dst[res] = c;
- if (!c)
- return res;
- res++;
- max--;
- }
-
- /*
- * Uhhuh. We hit 'max'. But was that the user-specified maximum
- * too? If so, that's ok - we got as much as the user asked for.
- */
- if (res >= count)
- return res;
-
- /*
- * Nope: we hit the address space limit, and we still had more
- * characters the caller would have wanted. That's an EFAULT.
- */
- return -EFAULT;
-}
-
-/**
- * strncpy_from_user: - Copy a NUL terminated string from userspace.
- * @dst: Destination address, in kernel space. This buffer must be at
- * least @count bytes long.
- * @src: Source address, in user space.
- * @count: Maximum number of bytes to copy, including the trailing NUL.
- *
- * Copies a NUL-terminated string from userspace to kernel space.
- *
- * On success, returns the length of the string (not including the trailing
- * NUL).
- *
- * If access to userspace fails, returns -EFAULT (some data may have been
- * copied).
- *
- * If @count is smaller than the length of the string, copies @count bytes
- * and returns @count.
- */
-long
-strncpy_from_user(char *dst, const char __user *src, long count)
-{
- unsigned long max_addr, src_addr;
-
- if (unlikely(count <= 0))
- return 0;
-
- max_addr = current_thread_info()->addr_limit.seg;
- src_addr = (unsigned long)src;
- if (likely(src_addr < max_addr)) {
- unsigned long max = max_addr - src_addr;
- return do_strncpy_from_user(dst, src, count, max);
- }
- return -EFAULT;
-}
-EXPORT_SYMBOL(strncpy_from_user);