/* SPDX-License-Identifier: GPL-2.0 */ #ifndef __PARISC_UACCESS_H #define __PARISC_UACCESS_H /* * User space memory access functions */ #include #include #include #include /* * 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. */ #define access_ok(uaddr, size) \ ( (uaddr) == (uaddr) ) #define put_user __put_user #define get_user __get_user #if !defined(CONFIG_64BIT) #define LDD_USER(sr, val, ptr) __get_user_asm64(sr, val, ptr) #define STD_USER(sr, x, ptr) __put_user_asm64(sr, x, ptr) #else #define LDD_USER(sr, val, ptr) __get_user_asm(sr, val, "ldd", ptr) #define STD_USER(sr, x, ptr) __put_user_asm(sr, "std", x, ptr) #endif /* * The exception table contains two values: the first is the relative offset to * the address of the instruction that is allowed to fault, and the second is * the relative offset to the address of the fixup routine. Since relative * addresses are used, 32bit values are sufficient even on 64bit kernel. */ #define ARCH_HAS_RELATIVE_EXTABLE struct exception_table_entry { int insn; /* relative address of insn that is allowed to fault. */ int fixup; /* relative address of fixup routine */ }; #define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\ ".section __ex_table,\"aw\"\n" \ ".word (" #fault_addr " - .), (" #except_addr " - .)\n\t" \ ".previous\n" /* * ASM_EXCEPTIONTABLE_ENTRY_EFAULT() creates a special exception table entry * (with lowest bit set) for which the fault handler in fixup_exception() will * load -EFAULT into %r29 for a read or write fault, and zeroes the target * register in case of a read fault in get_user(). */ #define ASM_EXCEPTIONTABLE_REG 29 #define ASM_EXCEPTIONTABLE_VAR(__variable) \ register long __variable __asm__ ("r29") = 0 #define ASM_EXCEPTIONTABLE_ENTRY_EFAULT( fault_addr, except_addr )\ ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr + 1) #define __get_user_internal(sr, val, ptr) \ ({ \ ASM_EXCEPTIONTABLE_VAR(__gu_err); \ \ switch (sizeof(*(ptr))) { \ case 1: __get_user_asm(sr, val, "ldb", ptr); break; \ case 2: __get_user_asm(sr, val, "ldh", ptr); break; \ case 4: __get_user_asm(sr, val, "ldw", ptr); break; \ case 8: LDD_USER(sr, val, ptr); break; \ default: BUILD_BUG(); \ } \ \ __gu_err; \ }) #define __get_user(val, ptr) \ ({ \ __get_user_internal("%%sr3,", val, ptr); \ }) #define __get_user_asm(sr, val, ldx, ptr) \ { \ register long __gu_val; \ \ __asm__("1: " ldx " 0(" sr "%2),%0\n" \ "9:\n" \ ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \ : "=r"(__gu_val), "+r"(__gu_err) \ : "r"(ptr)); \ \ (val) = (__force __typeof__(*(ptr))) __gu_val; \ } #define HAVE_GET_KERNEL_NOFAULT #define __get_kernel_nofault(dst, src, type, err_label) \ { \ type __z; \ long __err; \ __err = __get_user_internal("%%sr0,", __z, (type *)(src)); \ if (unlikely(__err)) \ goto err_label; \ else \ *(type *)(dst) = __z; \ } #if !defined(CONFIG_64BIT) #define __get_user_asm64(sr, val, ptr) \ { \ union { \ unsigned long long l; \ __typeof__(*(ptr)) t; \ } __gu_tmp; \ \ __asm__(" copy %%r0,%R0\n" \ "1: ldw 0(" sr "%2),%0\n" \ "2: ldw 4(" sr "%2),%R0\n" \ "9:\n" \ ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \ ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \ : "=&r"(__gu_tmp.l), "+r"(__gu_err) \ : "r"(ptr)); \ \ (val) = __gu_tmp.t; \ } #endif /* !defined(CONFIG_64BIT) */ #define __put_user_internal(sr, x, ptr) \ ({ \ ASM_EXCEPTIONTABLE_VAR(__pu_err); \ \ switch (sizeof(*(ptr))) { \ case 1: __put_user_asm(sr, "stb", x, ptr); break; \ case 2: __put_user_asm(sr, "sth", x, ptr); break; \ case 4: __put_user_asm(sr, "stw", x, ptr); break; \ case 8: STD_USER(sr, x, ptr); break; \ default: BUILD_BUG(); \ } \ \ __pu_err; \ }) #define __put_user(x, ptr) \ ({ \ __typeof__(&*(ptr)) __ptr = ptr; \ __typeof__(*(__ptr)) __x = (__typeof__(*(__ptr)))(x); \ __put_user_internal("%%sr3,", __x, __ptr); \ }) #define __put_kernel_nofault(dst, src, type, err_label) \ { \ type __z = *(type *)(src); \ long __err; \ __err = __put_user_internal("%%sr0,", __z, (type *)(dst)); \ if (unlikely(__err)) \ goto err_label; \ } /* * 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 fixups are executed in the context of the fault, * and any registers used there must be listed as clobbers. * The register holding the possible EFAULT error (ASM_EXCEPTIONTABLE_REG) * is already listed as input and output register. */ #define __put_user_asm(sr, stx, x, ptr) \ __asm__ __volatile__ ( \ "1: " stx " %2,0(" sr "%1)\n" \ "9:\n" \ ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \ : "+r"(__pu_err) \ : "r"(ptr), "r"(x)) #if !defined(CONFIG_64BIT) #define __put_user_asm64(sr, __val, ptr) do { \ __asm__ __volatile__ ( \ "1: stw %2,0(" sr "%1)\n" \ "2: stw %R2,4(" sr "%1)\n" \ "9:\n" \ ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \ ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \ : "+r"(__pu_err) \ : "r"(ptr), "r"(__val)); \ } while (0) #endif /* !defined(CONFIG_64BIT) */ /* * Complex access routines -- external declarations */ extern long strncpy_from_user(char *, const char __user *, long); extern __must_check unsigned lclear_user(void __user *, unsigned long); extern __must_check long strnlen_user(const char __user *src, long n); /* * Complex access routines -- macros */ #define clear_user lclear_user #define __clear_user lclear_user unsigned long __must_check raw_copy_to_user(void __user *dst, const void *src, unsigned long len); unsigned long __must_check raw_copy_from_user(void *dst, const void __user *src, unsigned long len); #define INLINE_COPY_TO_USER #define INLINE_COPY_FROM_USER struct pt_regs; int fixup_exception(struct pt_regs *regs); #endif /* __PARISC_UACCESS_H */