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authorLinus Torvalds <torvalds@linux-foundation.org>2008-10-23 10:22:01 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-10-23 10:22:01 -0700
commit5b34653963de7a6d0d8c783527457d68fddc60fb (patch)
tree1a234741e1823a54cd0514616f783b4cf503a528 /arch/um/include/shared/um_uaccess.h
parent765426e8ee4c0ab2bc9d44951f4865b8494cdbd0 (diff)
parent5e1b00758b5a8bee9d42515bffdaf305a32f1b04 (diff)
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Merge branch 'x86/um-header' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86/um-header' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (26 commits) x86: canonicalize remaining header guards x86: drop double underscores from header guards x86: Fix ASM_X86__ header guards x86, um: get rid of uml-config.h x86, um: get rid of arch/um/Kconfig.arch x86, um: get rid of arch/um/os symlink x86, um: get rid of excessive includes of uml-config.h x86, um: get rid of header symlinks x86, um: merge Kconfig.i386 and Kconfig.x86_64 x86, um: get rid of sysdep symlink x86, um: trim the junk from uml ptrace-*.h x86, um: take vm-flags.h to sysdep x86, um: get rid of uml asm/arch x86, um: get rid of uml highmem.h x86, um: get rid of uml unistd.h x86, um: get rid of system.h -> system.h include x86, um: uml atomic.h is not needed anymore x86, um: untangle uml ldt.h x86, um: get rid of more uml asm/arch uses x86, um: remove dead header (uml module-generic.h; never used these days) ...
Diffstat (limited to 'arch/um/include/shared/um_uaccess.h')
-rw-r--r--arch/um/include/shared/um_uaccess.h97
1 files changed, 97 insertions, 0 deletions
diff --git a/arch/um/include/shared/um_uaccess.h b/arch/um/include/shared/um_uaccess.h
new file mode 100644
index 000000000000..45c04999d670
--- /dev/null
+++ b/arch/um/include/shared/um_uaccess.h
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __ARCH_UM_UACCESS_H
+#define __ARCH_UM_UACCESS_H
+
+#include <asm/elf.h>
+#include <asm/fixmap.h>
+#include "sysdep/archsetjmp.h"
+
+#define __under_task_size(addr, size) \
+ (((unsigned long) (addr) < TASK_SIZE) && \
+ (((unsigned long) (addr) + (size)) < TASK_SIZE))
+
+#define __access_ok_vsyscall(type, addr, size) \
+ ((type == VERIFY_READ) && \
+ ((unsigned long) (addr) >= FIXADDR_USER_START) && \
+ ((unsigned long) (addr) + (size) <= FIXADDR_USER_END) && \
+ ((unsigned long) (addr) + (size) >= (unsigned long)(addr)))
+
+#define __addr_range_nowrap(addr, size) \
+ ((unsigned long) (addr) <= ((unsigned long) (addr) + (size)))
+
+#define access_ok(type, addr, size) \
+ (__addr_range_nowrap(addr, size) && \
+ (__under_task_size(addr, size) || \
+ __access_ok_vsyscall(type, addr, size) || \
+ segment_eq(get_fs(), KERNEL_DS)))
+
+extern int copy_from_user(void *to, const void __user *from, int n);
+extern int copy_to_user(void __user *to, const void *from, int n);
+
+extern int __do_copy_to_user(void *to, const void *from, int n,
+ void **fault_addr, jmp_buf **fault_catcher);
+
+/*
+ * 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.
+ */
+
+extern int strncpy_from_user(char *dst, const char __user *src, int count);
+
+/*
+ * __clear_user: - Zero a block of memory in user space, with less checking.
+ * @to: Destination address, in user space.
+ * @n: Number of bytes to zero.
+ *
+ * Zero a block of memory in user space. Caller must check
+ * the specified block with access_ok() before calling this function.
+ *
+ * Returns number of bytes that could not be cleared.
+ * On success, this will be zero.
+ */
+extern int __clear_user(void __user *mem, int len);
+
+/*
+ * clear_user: - Zero a block of memory in user space.
+ * @to: Destination address, in user space.
+ * @n: Number of bytes to zero.
+ *
+ * Zero a block of memory in user space.
+ *
+ * Returns number of bytes that could not be cleared.
+ * On success, this will be zero.
+ */
+extern int clear_user(void __user *mem, int len);
+
+/*
+ * strlen_user: - Get the size of a string in user space.
+ * @str: The string to measure.
+ * @n: The maximum valid length
+ *
+ * Get the size of a NUL-terminated string in user space.
+ *
+ * Returns the size of the string INCLUDING the terminating NUL.
+ * On exception, returns 0.
+ * If the string is too long, returns a value greater than @n.
+ */
+extern int strnlen_user(const void __user *str, int len);
+
+#endif