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-rw-r--r--arch/parisc/include/asm/uaccess.h260
1 files changed, 260 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/uaccess.h b/arch/parisc/include/asm/uaccess.h
new file mode 100644
index 000000000..0abdd4c60
--- /dev/null
+++ b/arch/parisc/include/asm/uaccess.h
@@ -0,0 +1,260 @@
+#ifndef __PARISC_UACCESS_H
+#define __PARISC_UACCESS_H
+
+/*
+ * User space memory access functions
+ */
+#include <asm/page.h>
+#include <asm/cache.h>
+#include <asm/errno.h>
+#include <asm-generic/uaccess-unaligned.h>
+
+#include <linux/bug.h>
+
+#define VERIFY_READ 0
+#define VERIFY_WRITE 1
+
+#define KERNEL_DS ((mm_segment_t){0})
+#define USER_DS ((mm_segment_t){1})
+
+#define segment_eq(a, b) ((a).seg == (b).seg)
+
+#define get_ds() (KERNEL_DS)
+#define get_fs() (current_thread_info()->addr_limit)
+#define set_fs(x) (current_thread_info()->addr_limit = (x))
+
+/*
+ * Note that since kernel addresses are in a separate address space on
+ * parisc, we don't need to do anything for access_ok().
+ * We just let the page fault handler do the right thing. This also means
+ * that put_user is the same as __put_user, etc.
+ */
+
+static inline long access_ok(int type, const void __user * addr,
+ unsigned long size)
+{
+ return 1;
+}
+
+#define put_user __put_user
+#define get_user __get_user
+
+#if !defined(CONFIG_64BIT)
+#define LDD_KERNEL(ptr) BUILD_BUG()
+#define LDD_USER(ptr) BUILD_BUG()
+#define STD_KERNEL(x, ptr) __put_kernel_asm64(x, ptr)
+#define STD_USER(x, ptr) __put_user_asm64(x, ptr)
+#define ASM_WORD_INSN ".word\t"
+#else
+#define LDD_KERNEL(ptr) __get_kernel_asm("ldd", ptr)
+#define LDD_USER(ptr) __get_user_asm("ldd", ptr)
+#define STD_KERNEL(x, ptr) __put_kernel_asm("std", x, ptr)
+#define STD_USER(x, ptr) __put_user_asm("std", x, ptr)
+#define ASM_WORD_INSN ".dword\t"
+#endif
+
+/*
+ * The exception table contains two values: the first is an address
+ * for an instruction that is allowed to fault, and the second is
+ * the address to the fixup routine. Even on a 64bit kernel we could
+ * use a 32bit (unsigned int) address here.
+ */
+
+struct exception_table_entry {
+ unsigned long insn; /* address of insn that is allowed to fault. */
+ unsigned long fixup; /* fixup routine */
+};
+
+#define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\
+ ".section __ex_table,\"aw\"\n" \
+ ASM_WORD_INSN #fault_addr ", " #except_addr "\n\t" \
+ ".previous\n"
+
+/*
+ * The page fault handler stores, in a per-cpu area, the following information
+ * if a fixup routine is available.
+ */
+struct exception_data {
+ unsigned long fault_ip;
+ unsigned long fault_space;
+ unsigned long fault_addr;
+};
+
+#define __get_user(x, ptr) \
+({ \
+ register long __gu_err __asm__ ("r8") = 0; \
+ register long __gu_val __asm__ ("r9") = 0; \
+ \
+ if (segment_eq(get_fs(), KERNEL_DS)) { \
+ switch (sizeof(*(ptr))) { \
+ case 1: __get_kernel_asm("ldb", ptr); break; \
+ case 2: __get_kernel_asm("ldh", ptr); break; \
+ case 4: __get_kernel_asm("ldw", ptr); break; \
+ case 8: LDD_KERNEL(ptr); break; \
+ default: BUILD_BUG(); break; \
+ } \
+ } \
+ else { \
+ switch (sizeof(*(ptr))) { \
+ case 1: __get_user_asm("ldb", ptr); break; \
+ case 2: __get_user_asm("ldh", ptr); break; \
+ case 4: __get_user_asm("ldw", ptr); break; \
+ case 8: LDD_USER(ptr); break; \
+ default: BUILD_BUG(); break; \
+ } \
+ } \
+ \
+ (x) = (__force __typeof__(*(ptr))) __gu_val; \
+ __gu_err; \
+})
+
+#define __get_kernel_asm(ldx, ptr) \
+ __asm__("\n1:\t" ldx "\t0(%2),%0\n\t" \
+ ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
+ : "=r"(__gu_val), "=r"(__gu_err) \
+ : "r"(ptr), "1"(__gu_err) \
+ : "r1");
+
+#define __get_user_asm(ldx, ptr) \
+ __asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n\t" \
+ ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
+ : "=r"(__gu_val), "=r"(__gu_err) \
+ : "r"(ptr), "1"(__gu_err) \
+ : "r1");
+
+#define __put_user(x, ptr) \
+({ \
+ register long __pu_err __asm__ ("r8") = 0; \
+ __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \
+ \
+ if (segment_eq(get_fs(), KERNEL_DS)) { \
+ switch (sizeof(*(ptr))) { \
+ case 1: __put_kernel_asm("stb", __x, ptr); break; \
+ case 2: __put_kernel_asm("sth", __x, ptr); break; \
+ case 4: __put_kernel_asm("stw", __x, ptr); break; \
+ case 8: STD_KERNEL(__x, ptr); break; \
+ default: BUILD_BUG(); break; \
+ } \
+ } \
+ else { \
+ switch (sizeof(*(ptr))) { \
+ case 1: __put_user_asm("stb", __x, ptr); break; \
+ case 2: __put_user_asm("sth", __x, ptr); break; \
+ case 4: __put_user_asm("stw", __x, ptr); break; \
+ case 8: STD_USER(__x, ptr); break; \
+ default: BUILD_BUG(); break; \
+ } \
+ } \
+ \
+ __pu_err; \
+})
+
+/*
+ * The "__put_user/kernel_asm()" macros tell gcc they read from memory
+ * instead of writing. This is because they do not write to any memory
+ * gcc knows about, so there are no aliasing issues. These macros must
+ * also be aware that "fixup_put_user_skip_[12]" are executed in the
+ * context of the fault, and any registers used there must be listed
+ * as clobbers. In this case only "r1" is used by the current routines.
+ * r8/r9 are already listed as err/val.
+ */
+
+#define __put_kernel_asm(stx, x, ptr) \
+ __asm__ __volatile__ ( \
+ "\n1:\t" stx "\t%2,0(%1)\n\t" \
+ ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\
+ : "=r"(__pu_err) \
+ : "r"(ptr), "r"(x), "0"(__pu_err) \
+ : "r1")
+
+#define __put_user_asm(stx, x, ptr) \
+ __asm__ __volatile__ ( \
+ "\n1:\t" stx "\t%2,0(%%sr3,%1)\n\t" \
+ ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\
+ : "=r"(__pu_err) \
+ : "r"(ptr), "r"(x), "0"(__pu_err) \
+ : "r1")
+
+
+#if !defined(CONFIG_64BIT)
+
+#define __put_kernel_asm64(__val, ptr) do { \
+ __asm__ __volatile__ ( \
+ "\n1:\tstw %2,0(%1)" \
+ "\n2:\tstw %R2,4(%1)\n\t" \
+ ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\
+ ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\
+ : "=r"(__pu_err) \
+ : "r"(ptr), "r"(__val), "0"(__pu_err) \
+ : "r1"); \
+} while (0)
+
+#define __put_user_asm64(__val, ptr) do { \
+ __asm__ __volatile__ ( \
+ "\n1:\tstw %2,0(%%sr3,%1)" \
+ "\n2:\tstw %R2,4(%%sr3,%1)\n\t" \
+ ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\
+ ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\
+ : "=r"(__pu_err) \
+ : "r"(ptr), "r"(__val), "0"(__pu_err) \
+ : "r1"); \
+} while (0)
+
+#endif /* !defined(CONFIG_64BIT) */
+
+
+/*
+ * Complex access routines -- external declarations
+ */
+
+extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long);
+extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long);
+extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long);
+extern long strncpy_from_user(char *, const char __user *, long);
+extern unsigned lclear_user(void __user *, unsigned long);
+extern long lstrnlen_user(const char __user *, long);
+/*
+ * Complex access routines -- macros
+ */
+#define user_addr_max() (~0UL)
+
+#define strnlen_user lstrnlen_user
+#define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
+#define clear_user lclear_user
+#define __clear_user lclear_user
+
+unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len);
+#define __copy_to_user copy_to_user
+unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len);
+unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len);
+#define __copy_in_user copy_in_user
+#define __copy_to_user_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+
+extern void copy_from_user_overflow(void)
+#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
+ __compiletime_error("copy_from_user() buffer size is not provably correct")
+#else
+ __compiletime_warning("copy_from_user() buffer size is not provably correct")
+#endif
+;
+
+static inline unsigned long __must_check copy_from_user(void *to,
+ const void __user *from,
+ unsigned long n)
+{
+ int sz = __compiletime_object_size(to);
+ int ret = -EFAULT;
+
+ if (likely(sz == -1 || !__builtin_constant_p(n) || sz >= n))
+ ret = __copy_from_user(to, from, n);
+ else
+ copy_from_user_overflow();
+
+ return ret;
+}
+
+struct pt_regs;
+int fixup_exception(struct pt_regs *regs);
+
+#endif /* __PARISC_UACCESS_H */