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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/alpha/include/asm/uaccess.h
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/alpha/include/asm/uaccess.h')
-rw-r--r--arch/alpha/include/asm/uaccess.h292
1 files changed, 292 insertions, 0 deletions
diff --git a/arch/alpha/include/asm/uaccess.h b/arch/alpha/include/asm/uaccess.h
new file mode 100644
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+++ b/arch/alpha/include/asm/uaccess.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ALPHA_UACCESS_H
+#define __ALPHA_UACCESS_H
+
+#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.
+ *
+ * As the alpha uses the same address space for kernel and user
+ * data, we can just do these as direct assignments. (Of course, the
+ * exception handling means that it's no longer "just"...)
+ *
+ * Careful to not
+ * (a) re-use the arguments for side effects (sizeof/typeof is ok)
+ * (b) require any knowledge of processes at this stage
+ */
+#define put_user(x, ptr) \
+ __put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
+#define get_user(x, ptr) \
+ __get_user_check((x), (ptr), sizeof(*(ptr)))
+
+/*
+ * The "__xxx" versions do not do address space checking, useful when
+ * doing multiple accesses to the same area (the programmer has to do the
+ * checks by hand with "access_ok()")
+ */
+#define __put_user(x, ptr) \
+ __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
+#define __get_user(x, ptr) \
+ __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
+
+/*
+ * The "lda %1, 2b-1b(%0)" bits are magic to get the assembler to
+ * encode the bits we need for resolving the exception. See the
+ * more extensive comments with fixup_inline_exception below for
+ * more information.
+ */
+#define EXC(label,cont,res,err) \
+ ".section __ex_table,\"a\"\n" \
+ " .long "#label"-.\n" \
+ " lda "#res","#cont"-"#label"("#err")\n" \
+ ".previous\n"
+
+extern void __get_user_unknown(void);
+
+#define __get_user_nocheck(x, ptr, size) \
+({ \
+ long __gu_err = 0; \
+ unsigned long __gu_val; \
+ __chk_user_ptr(ptr); \
+ switch (size) { \
+ case 1: __get_user_8(ptr); break; \
+ case 2: __get_user_16(ptr); break; \
+ case 4: __get_user_32(ptr); break; \
+ case 8: __get_user_64(ptr); break; \
+ default: __get_user_unknown(); break; \
+ } \
+ (x) = (__force __typeof__(*(ptr))) __gu_val; \
+ __gu_err; \
+})
+
+#define __get_user_check(x, ptr, size) \
+({ \
+ long __gu_err = -EFAULT; \
+ unsigned long __gu_val = 0; \
+ const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
+ if (__access_ok(__gu_addr, size)) { \
+ __gu_err = 0; \
+ switch (size) { \
+ case 1: __get_user_8(__gu_addr); break; \
+ case 2: __get_user_16(__gu_addr); break; \
+ case 4: __get_user_32(__gu_addr); break; \
+ case 8: __get_user_64(__gu_addr); break; \
+ default: __get_user_unknown(); break; \
+ } \
+ } \
+ (x) = (__force __typeof__(*(ptr))) __gu_val; \
+ __gu_err; \
+})
+
+struct __large_struct { unsigned long buf[100]; };
+#define __m(x) (*(struct __large_struct __user *)(x))
+
+#define __get_user_64(addr) \
+ __asm__("1: ldq %0,%2\n" \
+ "2:\n" \
+ EXC(1b,2b,%0,%1) \
+ : "=r"(__gu_val), "=r"(__gu_err) \
+ : "m"(__m(addr)), "1"(__gu_err))
+
+#define __get_user_32(addr) \
+ __asm__("1: ldl %0,%2\n" \
+ "2:\n" \
+ EXC(1b,2b,%0,%1) \
+ : "=r"(__gu_val), "=r"(__gu_err) \
+ : "m"(__m(addr)), "1"(__gu_err))
+
+#ifdef __alpha_bwx__
+/* Those lucky bastards with ev56 and later CPUs can do byte/word moves. */
+
+#define __get_user_16(addr) \
+ __asm__("1: ldwu %0,%2\n" \
+ "2:\n" \
+ EXC(1b,2b,%0,%1) \
+ : "=r"(__gu_val), "=r"(__gu_err) \
+ : "m"(__m(addr)), "1"(__gu_err))
+
+#define __get_user_8(addr) \
+ __asm__("1: ldbu %0,%2\n" \
+ "2:\n" \
+ EXC(1b,2b,%0,%1) \
+ : "=r"(__gu_val), "=r"(__gu_err) \
+ : "m"(__m(addr)), "1"(__gu_err))
+#else
+/* Unfortunately, we can't get an unaligned access trap for the sub-word
+ load, so we have to do a general unaligned operation. */
+
+#define __get_user_16(addr) \
+{ \
+ long __gu_tmp; \
+ __asm__("1: ldq_u %0,0(%3)\n" \
+ "2: ldq_u %1,1(%3)\n" \
+ " extwl %0,%3,%0\n" \
+ " extwh %1,%3,%1\n" \
+ " or %0,%1,%0\n" \
+ "3:\n" \
+ EXC(1b,3b,%0,%2) \
+ EXC(2b,3b,%0,%2) \
+ : "=&r"(__gu_val), "=&r"(__gu_tmp), "=r"(__gu_err) \
+ : "r"(addr), "2"(__gu_err)); \
+}
+
+#define __get_user_8(addr) \
+ __asm__("1: ldq_u %0,0(%2)\n" \
+ " extbl %0,%2,%0\n" \
+ "2:\n" \
+ EXC(1b,2b,%0,%1) \
+ : "=&r"(__gu_val), "=r"(__gu_err) \
+ : "r"(addr), "1"(__gu_err))
+#endif
+
+extern void __put_user_unknown(void);
+
+#define __put_user_nocheck(x, ptr, size) \
+({ \
+ long __pu_err = 0; \
+ __chk_user_ptr(ptr); \
+ switch (size) { \
+ case 1: __put_user_8(x, ptr); break; \
+ case 2: __put_user_16(x, ptr); break; \
+ case 4: __put_user_32(x, ptr); break; \
+ case 8: __put_user_64(x, ptr); break; \
+ default: __put_user_unknown(); break; \
+ } \
+ __pu_err; \
+})
+
+#define __put_user_check(x, ptr, size) \
+({ \
+ long __pu_err = -EFAULT; \
+ __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
+ if (__access_ok(__pu_addr, size)) { \
+ __pu_err = 0; \
+ switch (size) { \
+ case 1: __put_user_8(x, __pu_addr); break; \
+ case 2: __put_user_16(x, __pu_addr); break; \
+ case 4: __put_user_32(x, __pu_addr); break; \
+ case 8: __put_user_64(x, __pu_addr); break; \
+ default: __put_user_unknown(); break; \
+ } \
+ } \
+ __pu_err; \
+})
+
+/*
+ * The "__put_user_xx()" 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
+ */
+#define __put_user_64(x, addr) \
+__asm__ __volatile__("1: stq %r2,%1\n" \
+ "2:\n" \
+ EXC(1b,2b,$31,%0) \
+ : "=r"(__pu_err) \
+ : "m" (__m(addr)), "rJ" (x), "0"(__pu_err))
+
+#define __put_user_32(x, addr) \
+__asm__ __volatile__("1: stl %r2,%1\n" \
+ "2:\n" \
+ EXC(1b,2b,$31,%0) \
+ : "=r"(__pu_err) \
+ : "m"(__m(addr)), "rJ"(x), "0"(__pu_err))
+
+#ifdef __alpha_bwx__
+/* Those lucky bastards with ev56 and later CPUs can do byte/word moves. */
+
+#define __put_user_16(x, addr) \
+__asm__ __volatile__("1: stw %r2,%1\n" \
+ "2:\n" \
+ EXC(1b,2b,$31,%0) \
+ : "=r"(__pu_err) \
+ : "m"(__m(addr)), "rJ"(x), "0"(__pu_err))
+
+#define __put_user_8(x, addr) \
+__asm__ __volatile__("1: stb %r2,%1\n" \
+ "2:\n" \
+ EXC(1b,2b,$31,%0) \
+ : "=r"(__pu_err) \
+ : "m"(__m(addr)), "rJ"(x), "0"(__pu_err))
+#else
+/* Unfortunately, we can't get an unaligned access trap for the sub-word
+ write, so we have to do a general unaligned operation. */
+
+#define __put_user_16(x, addr) \
+{ \
+ long __pu_tmp1, __pu_tmp2, __pu_tmp3, __pu_tmp4; \
+ __asm__ __volatile__( \
+ "1: ldq_u %2,1(%5)\n" \
+ "2: ldq_u %1,0(%5)\n" \
+ " inswh %6,%5,%4\n" \
+ " inswl %6,%5,%3\n" \
+ " mskwh %2,%5,%2\n" \
+ " mskwl %1,%5,%1\n" \
+ " or %2,%4,%2\n" \
+ " or %1,%3,%1\n" \
+ "3: stq_u %2,1(%5)\n" \
+ "4: stq_u %1,0(%5)\n" \
+ "5:\n" \
+ EXC(1b,5b,$31,%0) \
+ EXC(2b,5b,$31,%0) \
+ EXC(3b,5b,$31,%0) \
+ EXC(4b,5b,$31,%0) \
+ : "=r"(__pu_err), "=&r"(__pu_tmp1), \
+ "=&r"(__pu_tmp2), "=&r"(__pu_tmp3), \
+ "=&r"(__pu_tmp4) \
+ : "r"(addr), "r"((unsigned long)(x)), "0"(__pu_err)); \
+}
+
+#define __put_user_8(x, addr) \
+{ \
+ long __pu_tmp1, __pu_tmp2; \
+ __asm__ __volatile__( \
+ "1: ldq_u %1,0(%4)\n" \
+ " insbl %3,%4,%2\n" \
+ " mskbl %1,%4,%1\n" \
+ " or %1,%2,%1\n" \
+ "2: stq_u %1,0(%4)\n" \
+ "3:\n" \
+ EXC(1b,3b,$31,%0) \
+ EXC(2b,3b,$31,%0) \
+ : "=r"(__pu_err), \
+ "=&r"(__pu_tmp1), "=&r"(__pu_tmp2) \
+ : "r"((unsigned long)(x)), "r"(addr), "0"(__pu_err)); \
+}
+#endif
+
+
+/*
+ * Complex access routines
+ */
+
+extern long __copy_user(void *to, const void *from, long len);
+
+static inline unsigned long
+raw_copy_from_user(void *to, const void __user *from, unsigned long len)
+{
+ return __copy_user(to, (__force const void *)from, len);
+}
+
+static inline unsigned long
+raw_copy_to_user(void __user *to, const void *from, unsigned long len)
+{
+ return __copy_user((__force void *)to, from, len);
+}
+
+extern long __clear_user(void __user *to, long len);
+
+static inline long
+clear_user(void __user *to, long len)
+{
+ if (__access_ok(to, len))
+ len = __clear_user(to, len);
+ return len;
+}
+
+extern long strncpy_from_user(char *dest, const char __user *src, long count);
+extern __must_check long strnlen_user(const char __user *str, long n);
+
+#include <asm/extable.h>
+
+#endif /* __ALPHA_UACCESS_H */