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| author | Glauber Costa <gcosta@redhat.com> | 2008-06-25 11:05:11 -0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-07-09 09:14:18 +0200 |
| commit | 865e5b76505cdade261773bde32f785b3ce579f1 (patch) | |
| tree | 3ac122f2b95162b286b1a136ec4460f422b0d8b9 /include/asm-x86/uaccess.h | |
| parent | ca23386216b9d4fc3bb211101205077d2b2916ae (diff) | |
| download | lwn-865e5b76505cdade261773bde32f785b3ce579f1.tar.gz lwn-865e5b76505cdade261773bde32f785b3ce579f1.zip | |
x86: merge getuser.
Merge versions of getuser from uaccess_32.h and uaccess_64.h into
uaccess.h. There is a part which is 64-bit only (for now), and for
that, we use a __get_user_8 macro.
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include/asm-x86/uaccess.h')
| -rw-r--r-- | include/asm-x86/uaccess.h | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/include/asm-x86/uaccess.h b/include/asm-x86/uaccess.h index 2fc30c2a8a98..8cb580c0b411 100644 --- a/include/asm-x86/uaccess.h +++ b/include/asm-x86/uaccess.h @@ -120,6 +120,61 @@ extern int __get_user_bad(void); : "=a" (ret),"=d" (x) \ : "0" (ptr)) \ +/* Careful: we have to cast the result to the type of the pointer + * for sign reasons */ + +/** + * get_user: - Get a simple variable from user space. + * @x: Variable to store result. + * @ptr: Source address, in user space. + * + * Context: User context only. This function may sleep. + * + * This macro copies a single simple variable from user space to kernel + * space. It supports simple types like char and int, but not larger + * data types like structures or arrays. + * + * @ptr must have pointer-to-simple-variable type, and the result of + * dereferencing @ptr must be assignable to @x without a cast. + * + * Returns zero on success, or -EFAULT on error. + * On error, the variable @x is set to zero. + */ +#ifdef CONFIG_X86_32 +#define __get_user_8(__ret_gu, __val_gu, ptr) \ + __get_user_x(X, __ret_gu, __val_gu, ptr) +#else +#define __get_user_8(__ret_gu, __val_gu, ptr) \ + __get_user_x(8, __ret_gu, __val_gu, ptr) +#endif + +#define get_user(x, ptr) \ +({ \ + int __ret_gu; \ + unsigned long __val_gu; \ + __chk_user_ptr(ptr); \ + switch (sizeof(*(ptr))) { \ + case 1: \ + __get_user_x(1, __ret_gu, __val_gu, ptr); \ + break; \ + case 2: \ + __get_user_x(2, __ret_gu, __val_gu, ptr); \ + break; \ + case 4: \ + __get_user_x(4, __ret_gu, __val_gu, ptr); \ + break; \ + case 8: \ + __get_user_8(__ret_gu, __val_gu, ptr); \ + break; \ + default: \ + __get_user_x(X, __ret_gu, __val_gu, ptr); \ + break; \ + } \ + (x) = (__typeof__(*(ptr)))__val_gu; \ + __ret_gu; \ +}) + + #ifdef CONFIG_X86_32 # include "uaccess_32.h" #else |