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authorRussell King <rmk@dyn-67.arm.linux.org.uk>2008-08-02 10:55:55 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2008-08-02 21:32:35 +0100
commit4baa9922430662431231ac637adedddbb0cfb2d7 (patch)
treee8fb765ce3e41c01f33de34a0bc9494f0ae19818 /arch/arm/include/asm/uaccess.h
parentff4db0a043a5dee7180bdffd178e61cd02812c68 (diff)
[ARM] move include/asm-arm to arch/arm/include/asm
Move platform independent header files to arch/arm/include/asm, leaving those in asm/arch* and asm/plat* alone. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/include/asm/uaccess.h')
-rw-r--r--arch/arm/include/asm/uaccess.h444
1 files changed, 444 insertions, 0 deletions
diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h
new file mode 100644
index 00000000000..d0f51ff900b
--- /dev/null
+++ b/arch/arm/include/asm/uaccess.h
@@ -0,0 +1,444 @@
+/*
+ * arch/arm/include/asm/uaccess.h
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef _ASMARM_UACCESS_H
+#define _ASMARM_UACCESS_H
+
+/*
+ * User space memory access functions
+ */
+#include <linux/sched.h>
+#include <asm/errno.h>
+#include <asm/memory.h>
+#include <asm/domain.h>
+#include <asm/system.h>
+
+#define VERIFY_READ 0
+#define VERIFY_WRITE 1
+
+/*
+ * The exception table consists of pairs of addresses: the first is the
+ * address of an instruction that is allowed to fault, and the second is
+ * the address at which the program should continue. No registers are
+ * modified, so it is entirely up to the continuation code to figure out
+ * what to do.
+ *
+ * All the routines below use bits of fixup code that are out of line
+ * with the main instruction path. This means when everything is well,
+ * we don't even have to jump over them. Further, they do not intrude
+ * on our cache or tlb entries.
+ */
+
+struct exception_table_entry
+{
+ unsigned long insn, fixup;
+};
+
+extern int fixup_exception(struct pt_regs *regs);
+
+/*
+ * These two are intentionally not defined anywhere - if the kernel
+ * code generates any references to them, that's a bug.
+ */
+extern int __get_user_bad(void);
+extern int __put_user_bad(void);
+
+/*
+ * Note that this is actually 0x1,0000,0000
+ */
+#define KERNEL_DS 0x00000000
+#define get_ds() (KERNEL_DS)
+
+#ifdef CONFIG_MMU
+
+#define USER_DS TASK_SIZE
+#define get_fs() (current_thread_info()->addr_limit)
+
+static inline void set_fs(mm_segment_t fs)
+{
+ current_thread_info()->addr_limit = fs;
+ modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER);
+}
+
+#define segment_eq(a,b) ((a) == (b))
+
+#define __addr_ok(addr) ({ \
+ unsigned long flag; \
+ __asm__("cmp %2, %0; movlo %0, #0" \
+ : "=&r" (flag) \
+ : "0" (current_thread_info()->addr_limit), "r" (addr) \
+ : "cc"); \
+ (flag == 0); })
+
+/* We use 33-bit arithmetic here... */
+#define __range_ok(addr,size) ({ \
+ unsigned long flag, roksum; \
+ __chk_user_ptr(addr); \
+ __asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \
+ : "=&r" (flag), "=&r" (roksum) \
+ : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \
+ : "cc"); \
+ flag; })
+
+/*
+ * Single-value transfer routines. They automatically use the right
+ * size if we just have the right pointer type. Note that the functions
+ * which read from user space (*get_*) need to take care not to leak
+ * kernel data even if the calling code is buggy and fails to check
+ * the return value. This means zeroing out the destination variable
+ * or buffer on error. Normally this is done out of line by the
+ * fixup code, but there are a few places where it intrudes on the
+ * main code path. When we only write to user space, there is no
+ * problem.
+ */
+extern int __get_user_1(void *);
+extern int __get_user_2(void *);
+extern int __get_user_4(void *);
+
+#define __get_user_x(__r2,__p,__e,__s,__i...) \
+ __asm__ __volatile__ ( \
+ __asmeq("%0", "r0") __asmeq("%1", "r2") \
+ "bl __get_user_" #__s \
+ : "=&r" (__e), "=r" (__r2) \
+ : "0" (__p) \
+ : __i, "cc")
+
+#define get_user(x,p) \
+ ({ \
+ register const typeof(*(p)) __user *__p asm("r0") = (p);\
+ register unsigned long __r2 asm("r2"); \
+ register int __e asm("r0"); \
+ switch (sizeof(*(__p))) { \
+ case 1: \
+ __get_user_x(__r2, __p, __e, 1, "lr"); \
+ break; \
+ case 2: \
+ __get_user_x(__r2, __p, __e, 2, "r3", "lr"); \
+ break; \
+ case 4: \
+ __get_user_x(__r2, __p, __e, 4, "lr"); \
+ break; \
+ default: __e = __get_user_bad(); break; \
+ } \
+ x = (typeof(*(p))) __r2; \
+ __e; \
+ })
+
+extern int __put_user_1(void *, unsigned int);
+extern int __put_user_2(void *, unsigned int);
+extern int __put_user_4(void *, unsigned int);
+extern int __put_user_8(void *, unsigned long long);
+
+#define __put_user_x(__r2,__p,__e,__s) \
+ __asm__ __volatile__ ( \
+ __asmeq("%0", "r0") __asmeq("%2", "r2") \
+ "bl __put_user_" #__s \
+ : "=&r" (__e) \
+ : "0" (__p), "r" (__r2) \
+ : "ip", "lr", "cc")
+
+#define put_user(x,p) \
+ ({ \
+ register const typeof(*(p)) __r2 asm("r2") = (x); \
+ register const typeof(*(p)) __user *__p asm("r0") = (p);\
+ register int __e asm("r0"); \
+ switch (sizeof(*(__p))) { \
+ case 1: \
+ __put_user_x(__r2, __p, __e, 1); \
+ break; \
+ case 2: \
+ __put_user_x(__r2, __p, __e, 2); \
+ break; \
+ case 4: \
+ __put_user_x(__r2, __p, __e, 4); \
+ break; \
+ case 8: \
+ __put_user_x(__r2, __p, __e, 8); \
+ break; \
+ default: __e = __put_user_bad(); break; \
+ } \
+ __e; \
+ })
+
+#else /* CONFIG_MMU */
+
+/*
+ * uClinux has only one addr space, so has simplified address limits.
+ */
+#define USER_DS KERNEL_DS
+
+#define segment_eq(a,b) (1)
+#define __addr_ok(addr) (1)
+#define __range_ok(addr,size) (0)
+#define get_fs() (KERNEL_DS)
+
+static inline void set_fs(mm_segment_t fs)
+{
+}
+
+#define get_user(x,p) __get_user(x,p)
+#define put_user(x,p) __put_user(x,p)
+
+#endif /* CONFIG_MMU */
+
+#define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
+
+/*
+ * The "__xxx" versions of the user access functions do not verify the
+ * address space - it must have been done previously with a separate
+ * "access_ok()" call.
+ *
+ * The "xxx_error" versions set the third argument to EFAULT if an
+ * error occurs, and leave it unchanged on success. Note that these
+ * versions are void (ie, don't return a value as such).
+ */
+#define __get_user(x,ptr) \
+({ \
+ long __gu_err = 0; \
+ __get_user_err((x),(ptr),__gu_err); \
+ __gu_err; \
+})
+
+#define __get_user_error(x,ptr,err) \
+({ \
+ __get_user_err((x),(ptr),err); \
+ (void) 0; \
+})
+
+#define __get_user_err(x,ptr,err) \
+do { \
+ unsigned long __gu_addr = (unsigned long)(ptr); \
+ unsigned long __gu_val; \
+ __chk_user_ptr(ptr); \
+ switch (sizeof(*(ptr))) { \
+ case 1: __get_user_asm_byte(__gu_val,__gu_addr,err); break; \
+ case 2: __get_user_asm_half(__gu_val,__gu_addr,err); break; \
+ case 4: __get_user_asm_word(__gu_val,__gu_addr,err); break; \
+ default: (__gu_val) = __get_user_bad(); \
+ } \
+ (x) = (__typeof__(*(ptr)))__gu_val; \
+} while (0)
+
+#define __get_user_asm_byte(x,addr,err) \
+ __asm__ __volatile__( \
+ "1: ldrbt %1,[%2],#0\n" \
+ "2:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "3: mov %0, %3\n" \
+ " mov %1, #0\n" \
+ " b 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 3b\n" \
+ " .previous" \
+ : "+r" (err), "=&r" (x) \
+ : "r" (addr), "i" (-EFAULT) \
+ : "cc")
+
+#ifndef __ARMEB__
+#define __get_user_asm_half(x,__gu_addr,err) \
+({ \
+ unsigned long __b1, __b2; \
+ __get_user_asm_byte(__b1, __gu_addr, err); \
+ __get_user_asm_byte(__b2, __gu_addr + 1, err); \
+ (x) = __b1 | (__b2 << 8); \
+})
+#else
+#define __get_user_asm_half(x,__gu_addr,err) \
+({ \
+ unsigned long __b1, __b2; \
+ __get_user_asm_byte(__b1, __gu_addr, err); \
+ __get_user_asm_byte(__b2, __gu_addr + 1, err); \
+ (x) = (__b1 << 8) | __b2; \
+})
+#endif
+
+#define __get_user_asm_word(x,addr,err) \
+ __asm__ __volatile__( \
+ "1: ldrt %1,[%2],#0\n" \
+ "2:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "3: mov %0, %3\n" \
+ " mov %1, #0\n" \
+ " b 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 3b\n" \
+ " .previous" \
+ : "+r" (err), "=&r" (x) \
+ : "r" (addr), "i" (-EFAULT) \
+ : "cc")
+
+#define __put_user(x,ptr) \
+({ \
+ long __pu_err = 0; \
+ __put_user_err((x),(ptr),__pu_err); \
+ __pu_err; \
+})
+
+#define __put_user_error(x,ptr,err) \
+({ \
+ __put_user_err((x),(ptr),err); \
+ (void) 0; \
+})
+
+#define __put_user_err(x,ptr,err) \
+do { \
+ unsigned long __pu_addr = (unsigned long)(ptr); \
+ __typeof__(*(ptr)) __pu_val = (x); \
+ __chk_user_ptr(ptr); \
+ switch (sizeof(*(ptr))) { \
+ case 1: __put_user_asm_byte(__pu_val,__pu_addr,err); break; \
+ case 2: __put_user_asm_half(__pu_val,__pu_addr,err); break; \
+ case 4: __put_user_asm_word(__pu_val,__pu_addr,err); break; \
+ case 8: __put_user_asm_dword(__pu_val,__pu_addr,err); break; \
+ default: __put_user_bad(); \
+ } \
+} while (0)
+
+#define __put_user_asm_byte(x,__pu_addr,err) \
+ __asm__ __volatile__( \
+ "1: strbt %1,[%2],#0\n" \
+ "2:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "3: mov %0, %3\n" \
+ " b 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 3b\n" \
+ " .previous" \
+ : "+r" (err) \
+ : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
+ : "cc")
+
+#ifndef __ARMEB__
+#define __put_user_asm_half(x,__pu_addr,err) \
+({ \
+ unsigned long __temp = (unsigned long)(x); \
+ __put_user_asm_byte(__temp, __pu_addr, err); \
+ __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
+})
+#else
+#define __put_user_asm_half(x,__pu_addr,err) \
+({ \
+ unsigned long __temp = (unsigned long)(x); \
+ __put_user_asm_byte(__temp >> 8, __pu_addr, err); \
+ __put_user_asm_byte(__temp, __pu_addr + 1, err); \
+})
+#endif
+
+#define __put_user_asm_word(x,__pu_addr,err) \
+ __asm__ __volatile__( \
+ "1: strt %1,[%2],#0\n" \
+ "2:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "3: mov %0, %3\n" \
+ " b 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 3b\n" \
+ " .previous" \
+ : "+r" (err) \
+ : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
+ : "cc")
+
+#ifndef __ARMEB__
+#define __reg_oper0 "%R2"
+#define __reg_oper1 "%Q2"
+#else
+#define __reg_oper0 "%Q2"
+#define __reg_oper1 "%R2"
+#endif
+
+#define __put_user_asm_dword(x,__pu_addr,err) \
+ __asm__ __volatile__( \
+ "1: strt " __reg_oper1 ", [%1], #4\n" \
+ "2: strt " __reg_oper0 ", [%1], #0\n" \
+ "3:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "4: mov %0, %3\n" \
+ " b 3b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 4b\n" \
+ " .long 2b, 4b\n" \
+ " .previous" \
+ : "+r" (err), "+r" (__pu_addr) \
+ : "r" (x), "i" (-EFAULT) \
+ : "cc")
+
+
+#ifdef CONFIG_MMU
+extern unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n);
+extern unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n);
+extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
+#else
+#define __copy_from_user(to,from,n) (memcpy(to, (void __force *)from, n), 0)
+#define __copy_to_user(to,from,n) (memcpy((void __force *)to, from, n), 0)
+#define __clear_user(addr,n) (memset((void __force *)addr, 0, n), 0)
+#endif
+
+extern unsigned long __must_check __strncpy_from_user(char *to, const char __user *from, unsigned long count);
+extern unsigned long __must_check __strnlen_user(const char __user *s, long n);
+
+static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+ if (access_ok(VERIFY_READ, from, n))
+ n = __copy_from_user(to, from, n);
+ else /* security hole - plug it */
+ memzero(to, n);
+ return n;
+}
+
+static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+ if (access_ok(VERIFY_WRITE, to, n))
+ n = __copy_to_user(to, from, n);
+ return n;
+}
+
+#define __copy_to_user_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+
+static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
+{
+ if (access_ok(VERIFY_WRITE, to, n))
+ n = __clear_user(to, n);
+ return n;
+}
+
+static inline long __must_check strncpy_from_user(char *dst, const char __user *src, long count)
+{
+ long res = -EFAULT;
+ if (access_ok(VERIFY_READ, src, 1))
+ res = __strncpy_from_user(dst, src, count);
+ return res;
+}
+
+#define strlen_user(s) strnlen_user(s, ~0UL >> 1)
+
+static inline long __must_check strnlen_user(const char __user *s, long n)
+{
+ unsigned long res = 0;
+
+ if (__addr_ok(s))
+ res = __strnlen_user(s, n);
+
+ return res;
+}
+
+#endif /* _ASMARM_UACCESS_H */