/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ARCH_POWERPC_UACCESS_H #define _ARCH_POWERPC_UACCESS_H #include <asm/processor.h> #include <asm/page.h> #include <asm/extable.h> #include <asm/kup.h> #ifdef __powerpc64__ /* We use TASK_SIZE_USER64 as TASK_SIZE is not constant */ #define TASK_SIZE_MAX TASK_SIZE_USER64 #endif #include <asm-generic/access_ok.h> /* * These are the main single-value transfer routines. They automatically * use the right size if we just have the right pointer type. * * This gets kind of ugly. We want to return _two_ values in "get_user()" * and yet we don't want to do any pointers, because that is too much * of a performance impact. Thus we have a few rather ugly macros here, * and hide all the ugliness from the user. * * The "__xxx" versions of the user access functions are versions that * do not verify the address space, that must have been done previously * with a separate "access_ok()" call (this is used when we do multiple * accesses to the same area of user memory). * * As we use the same address space for kernel and user data on the * PowerPC, we can just do these as direct assignments. (Of course, the * exception handling means that it's no longer "just"...) * */ #define __put_user(x, ptr) \ ({ \ long __pu_err; \ __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ __typeof__(*(ptr)) __pu_val = (__typeof__(*(ptr)))(x); \ __typeof__(sizeof(*(ptr))) __pu_size = sizeof(*(ptr)); \ \ might_fault(); \ do { \ __label__ __pu_failed; \ \ allow_write_to_user(__pu_addr, __pu_size); \ __put_user_size_goto(__pu_val, __pu_addr, __pu_size, __pu_failed); \ prevent_write_to_user(__pu_addr, __pu_size); \ __pu_err = 0; \ break; \ \ __pu_failed: \ prevent_write_to_user(__pu_addr, __pu_size); \ __pu_err = -EFAULT; \ } while (0); \ \ __pu_err; \ }) #define put_user(x, ptr) \ ({ \ __typeof__(*(ptr)) __user *_pu_addr = (ptr); \ \ access_ok(_pu_addr, sizeof(*(ptr))) ? \ __put_user(x, _pu_addr) : -EFAULT; \ }) /* * We don't tell gcc that we are accessing memory, but this is OK * because we do not write to any memory gcc knows about, so there * are no aliasing issues. */ /* -mprefixed can generate offsets beyond range, fall back hack */ #ifdef CONFIG_PPC_KERNEL_PREFIXED #define __put_user_asm_goto(x, addr, label, op) \ asm_volatile_goto( \ "1: " op " %0,0(%1) # put_user\n" \ EX_TABLE(1b, %l2) \ : \ : "r" (x), "b" (addr) \ : \ : label) #else #define __put_user_asm_goto(x, addr, label, op) \ asm_volatile_goto( \ "1: " op "%U1%X1 %0,%1 # put_user\n" \ EX_TABLE(1b, %l2) \ : \ : "r" (x), "m<>" (*addr) \ : \ : label) #endif #ifdef __powerpc64__ #define __put_user_asm2_goto(x, ptr, label) \ __put_user_asm_goto(x, ptr, label, "std") #else /* __powerpc64__ */ #define __put_user_asm2_goto(x, addr, label) \ asm_volatile_goto( \ "1: stw%X1 %0, %1\n" \ "2: stw%X1 %L0, %L1\n" \ EX_TABLE(1b, %l2) \ EX_TABLE(2b, %l2) \ : \ : "r" (x), "m" (*addr) \ : \ : label) #endif /* __powerpc64__ */ #define __put_user_size_goto(x, ptr, size, label) \ do { \ __typeof__(*(ptr)) __user *__pus_addr = (ptr); \ \ switch (size) { \ case 1: __put_user_asm_goto(x, __pus_addr, label, "stb"); break; \ case 2: __put_user_asm_goto(x, __pus_addr, label, "sth"); break; \ case 4: __put_user_asm_goto(x, __pus_addr, label, "stw"); break; \ case 8: __put_user_asm2_goto(x, __pus_addr, label); break; \ default: BUILD_BUG(); \ } \ } while (0) /* * This does an atomic 128 byte aligned load from userspace. * Upto caller to do enable_kernel_vmx() before calling! */ #define __get_user_atomic_128_aligned(kaddr, uaddr, err) \ __asm__ __volatile__( \ ".machine push\n" \ ".machine altivec\n" \ "1: lvx 0,0,%1 # get user\n" \ " stvx 0,0,%2 # put kernel\n" \ ".machine pop\n" \ "2:\n" \ ".section .fixup,\"ax\"\n" \ "3: li %0,%3\n" \ " b 2b\n" \ ".previous\n" \ EX_TABLE(1b, 3b) \ : "=r" (err) \ : "b" (uaddr), "b" (kaddr), "i" (-EFAULT), "0" (err)) #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT /* -mprefixed can generate offsets beyond range, fall back hack */ #ifdef CONFIG_PPC_KERNEL_PREFIXED #define __get_user_asm_goto(x, addr, label, op) \ asm_volatile_goto( \ "1: "op" %0,0(%1) # get_user\n" \ EX_TABLE(1b, %l2) \ : "=r" (x) \ : "b" (addr) \ : \ : label) #else #define __get_user_asm_goto(x, addr, label, op) \ asm_volatile_goto( \ "1: "op"%U1%X1 %0, %1 # get_user\n" \ EX_TABLE(1b, %l2) \ : "=r" (x) \ : "m<>" (*addr) \ : \ : label) #endif #ifdef __powerpc64__ #define __get_user_asm2_goto(x, addr, label) \ __get_user_asm_goto(x, addr, label, "ld") #else /* __powerpc64__ */ #define __get_user_asm2_goto(x, addr, label) \ asm_volatile_goto( \ "1: lwz%X1 %0, %1\n" \ "2: lwz%X1 %L0, %L1\n" \ EX_TABLE(1b, %l2) \ EX_TABLE(2b, %l2) \ : "=&r" (x) \ : "m" (*addr) \ : \ : label) #endif /* __powerpc64__ */ #define __get_user_size_goto(x, ptr, size, label) \ do { \ BUILD_BUG_ON(size > sizeof(x)); \ switch (size) { \ case 1: __get_user_asm_goto(x, (u8 __user *)ptr, label, "lbz"); break; \ case 2: __get_user_asm_goto(x, (u16 __user *)ptr, label, "lhz"); break; \ case 4: __get_user_asm_goto(x, (u32 __user *)ptr, label, "lwz"); break; \ case 8: __get_user_asm2_goto(x, (u64 __user *)ptr, label); break; \ default: x = 0; BUILD_BUG(); \ } \ } while (0) #define __get_user_size_allowed(x, ptr, size, retval) \ do { \ __label__ __gus_failed; \ \ __get_user_size_goto(x, ptr, size, __gus_failed); \ retval = 0; \ break; \ __gus_failed: \ x = 0; \ retval = -EFAULT; \ } while (0) #else /* CONFIG_CC_HAS_ASM_GOTO_OUTPUT */ #define __get_user_asm(x, addr, err, op) \ __asm__ __volatile__( \ "1: "op"%U2%X2 %1, %2 # get_user\n" \ "2:\n" \ ".section .fixup,\"ax\"\n" \ "3: li %0,%3\n" \ " li %1,0\n" \ " b 2b\n" \ ".previous\n" \ EX_TABLE(1b, 3b) \ : "=r" (err), "=r" (x) \ : "m<>" (*addr), "i" (-EFAULT), "0" (err)) #ifdef __powerpc64__ #define __get_user_asm2(x, addr, err) \ __get_user_asm(x, addr, err, "ld") #else /* __powerpc64__ */ #define __get_user_asm2(x, addr, err) \ __asm__ __volatile__( \ "1: lwz%X2 %1, %2\n" \ "2: lwz%X2 %L1, %L2\n" \ "3:\n" \ ".section .fixup,\"ax\"\n" \ "4: li %0,%3\n" \ " li %1,0\n" \ " li %1+1,0\n" \ " b 3b\n" \ ".previous\n" \ EX_TABLE(1b, 4b) \ EX_TABLE(2b, 4b) \ : "=r" (err), "=&r" (x) \ : "m" (*addr), "i" (-EFAULT), "0" (err)) #endif /* __powerpc64__ */ #define __get_user_size_allowed(x, ptr, size, retval) \ do { \ retval = 0; \ BUILD_BUG_ON(size > sizeof(x)); \ switch (size) { \ case 1: __get_user_asm(x, (u8 __user *)ptr, retval, "lbz"); break; \ case 2: __get_user_asm(x, (u16 __user *)ptr, retval, "lhz"); break; \ case 4: __get_user_asm(x, (u32 __user *)ptr, retval, "lwz"); break; \ case 8: __get_user_asm2(x, (u64 __user *)ptr, retval); break; \ default: x = 0; BUILD_BUG(); \ } \ } while (0) #define __get_user_size_goto(x, ptr, size, label) \ do { \ long __gus_retval; \ \ __get_user_size_allowed(x, ptr, size, __gus_retval); \ if (__gus_retval) \ goto label; \ } while (0) #endif /* CONFIG_CC_HAS_ASM_GOTO_OUTPUT */ /* * This is a type: either unsigned long, if the argument fits into * that type, or otherwise unsigned long long. */ #define __long_type(x) \ __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) #define __get_user(x, ptr) \ ({ \ long __gu_err; \ __long_type(*(ptr)) __gu_val; \ __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ __typeof__(sizeof(*(ptr))) __gu_size = sizeof(*(ptr)); \ \ might_fault(); \ allow_read_from_user(__gu_addr, __gu_size); \ __get_user_size_allowed(__gu_val, __gu_addr, __gu_size, __gu_err); \ prevent_read_from_user(__gu_addr, __gu_size); \ (x) = (__typeof__(*(ptr)))__gu_val; \ \ __gu_err; \ }) #define get_user(x, ptr) \ ({ \ __typeof__(*(ptr)) __user *_gu_addr = (ptr); \ \ access_ok(_gu_addr, sizeof(*(ptr))) ? \ __get_user(x, _gu_addr) : \ ((x) = (__force __typeof__(*(ptr)))0, -EFAULT); \ }) /* more complex routines */ extern unsigned long __copy_tofrom_user(void __user *to, const void __user *from, unsigned long size); #ifdef __powerpc64__ static inline unsigned long raw_copy_in_user(void __user *to, const void __user *from, unsigned long n) { unsigned long ret; allow_read_write_user(to, from, n); ret = __copy_tofrom_user(to, from, n); prevent_read_write_user(to, from, n); return ret; } #endif /* __powerpc64__ */ static inline unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n) { unsigned long ret; allow_read_from_user(from, n); ret = __copy_tofrom_user((__force void __user *)to, from, n); prevent_read_from_user(from, n); return ret; } static inline unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n) { unsigned long ret; allow_write_to_user(to, n); ret = __copy_tofrom_user(to, (__force const void __user *)from, n); prevent_write_to_user(to, n); return ret; } unsigned long __arch_clear_user(void __user *addr, unsigned long size); static inline unsigned long __clear_user(void __user *addr, unsigned long size) { unsigned long ret; might_fault(); allow_write_to_user(addr, size); ret = __arch_clear_user(addr, size); prevent_write_to_user(addr, size); return ret; } static inline unsigned long clear_user(void __user *addr, unsigned long size) { return likely(access_ok(addr, size)) ? __clear_user(addr, size) : size; } extern long strncpy_from_user(char *dst, const char __user *src, long count); extern __must_check long strnlen_user(const char __user *str, long n); #ifdef CONFIG_ARCH_HAS_COPY_MC unsigned long __must_check copy_mc_generic(void *to, const void *from, unsigned long size); static inline unsigned long __must_check copy_mc_to_kernel(void *to, const void *from, unsigned long size) { return copy_mc_generic(to, from, size); } #define copy_mc_to_kernel copy_mc_to_kernel static inline unsigned long __must_check copy_mc_to_user(void __user *to, const void *from, unsigned long n) { if (check_copy_size(from, n, true)) { if (access_ok(to, n)) { allow_write_to_user(to, n); n = copy_mc_generic((void *)to, from, n); prevent_write_to_user(to, n); } } return n; } #endif extern long __copy_from_user_flushcache(void *dst, const void __user *src, unsigned size); static __must_check __always_inline bool user_access_begin(const void __user *ptr, size_t len) { if (unlikely(!access_ok(ptr, len))) return false; might_fault(); allow_read_write_user((void __user *)ptr, ptr, len); return true; } #define user_access_begin user_access_begin #define user_access_end prevent_current_access_user #define user_access_save prevent_user_access_return #define user_access_restore restore_user_access static __must_check __always_inline bool user_read_access_begin(const void __user *ptr, size_t len) { if (unlikely(!access_ok(ptr, len))) return false; might_fault(); allow_read_from_user(ptr, len); return true; } #define user_read_access_begin user_read_access_begin #define user_read_access_end prevent_current_read_from_user static __must_check __always_inline bool user_write_access_begin(const void __user *ptr, size_t len) { if (unlikely(!access_ok(ptr, len))) return false; might_fault(); allow_write_to_user((void __user *)ptr, len); return true; } #define user_write_access_begin user_write_access_begin #define user_write_access_end prevent_current_write_to_user #define unsafe_get_user(x, p, e) do { \ __long_type(*(p)) __gu_val; \ __typeof__(*(p)) __user *__gu_addr = (p); \ \ __get_user_size_goto(__gu_val, __gu_addr, sizeof(*(p)), e); \ (x) = (__typeof__(*(p)))__gu_val; \ } while (0) #define unsafe_put_user(x, p, e) \ __put_user_size_goto((__typeof__(*(p)))(x), (p), sizeof(*(p)), e) #define unsafe_copy_from_user(d, s, l, e) \ do { \ u8 *_dst = (u8 *)(d); \ const u8 __user *_src = (const u8 __user *)(s); \ size_t _len = (l); \ int _i; \ \ for (_i = 0; _i < (_len & ~(sizeof(u64) - 1)); _i += sizeof(u64)) \ unsafe_get_user(*(u64 *)(_dst + _i), (u64 __user *)(_src + _i), e); \ if (_len & 4) { \ unsafe_get_user(*(u32 *)(_dst + _i), (u32 __user *)(_src + _i), e); \ _i += 4; \ } \ if (_len & 2) { \ unsafe_get_user(*(u16 *)(_dst + _i), (u16 __user *)(_src + _i), e); \ _i += 2; \ } \ if (_len & 1) \ unsafe_get_user(*(u8 *)(_dst + _i), (u8 __user *)(_src + _i), e); \ } while (0) #define unsafe_copy_to_user(d, s, l, e) \ do { \ u8 __user *_dst = (u8 __user *)(d); \ const u8 *_src = (const u8 *)(s); \ size_t _len = (l); \ int _i; \ \ for (_i = 0; _i < (_len & ~(sizeof(u64) - 1)); _i += sizeof(u64)) \ unsafe_put_user(*(u64 *)(_src + _i), (u64 __user *)(_dst + _i), e); \ if (_len & 4) { \ unsafe_put_user(*(u32*)(_src + _i), (u32 __user *)(_dst + _i), e); \ _i += 4; \ } \ if (_len & 2) { \ unsafe_put_user(*(u16*)(_src + _i), (u16 __user *)(_dst + _i), e); \ _i += 2; \ } \ if (_len & 1) \ unsafe_put_user(*(u8*)(_src + _i), (u8 __user *)(_dst + _i), e); \ } while (0) #define __get_kernel_nofault(dst, src, type, err_label) \ __get_user_size_goto(*((type *)(dst)), \ (__force type __user *)(src), sizeof(type), err_label) #define __put_kernel_nofault(dst, src, type, err_label) \ __put_user_size_goto(*((type *)(src)), \ (__force type __user *)(dst), sizeof(type), err_label) #endif /* _ARCH_POWERPC_UACCESS_H */