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-rw-r--r--arch/x86/lib/usercopy_32.c359
1 files changed, 359 insertions, 0 deletions
diff --git a/arch/x86/lib/usercopy_32.c b/arch/x86/lib/usercopy_32.c
new file mode 100644
index 000000000..7add8ba06
--- /dev/null
+++ b/arch/x86/lib/usercopy_32.c
@@ -0,0 +1,359 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * User address space access functions.
+ * The non inlined parts of asm-i386/uaccess.h are here.
+ *
+ * Copyright 1997 Andi Kleen <ak@muc.de>
+ * Copyright 1997 Linus Torvalds
+ */
+#include <linux/export.h>
+#include <linux/uaccess.h>
+#include <asm/mmx.h>
+#include <asm/asm.h>
+
+#ifdef CONFIG_X86_INTEL_USERCOPY
+/*
+ * Alignment at which movsl is preferred for bulk memory copies.
+ */
+struct movsl_mask movsl_mask __read_mostly;
+#endif
+
+static inline int __movsl_is_ok(unsigned long a1, unsigned long a2, unsigned long n)
+{
+#ifdef CONFIG_X86_INTEL_USERCOPY
+ if (n >= 64 && ((a1 ^ a2) & movsl_mask.mask))
+ return 0;
+#endif
+ return 1;
+}
+#define movsl_is_ok(a1, a2, n) \
+ __movsl_is_ok((unsigned long)(a1), (unsigned long)(a2), (n))
+
+/*
+ * Zero Userspace
+ */
+
+#define __do_clear_user(addr,size) \
+do { \
+ int __d0; \
+ might_fault(); \
+ __asm__ __volatile__( \
+ ASM_STAC "\n" \
+ "0: rep; stosl\n" \
+ " movl %2,%0\n" \
+ "1: rep; stosb\n" \
+ "2: " ASM_CLAC "\n" \
+ ".section .fixup,\"ax\"\n" \
+ "3: lea 0(%2,%0,4),%0\n" \
+ " jmp 2b\n" \
+ ".previous\n" \
+ _ASM_EXTABLE(0b,3b) \
+ _ASM_EXTABLE(1b,2b) \
+ : "=&c"(size), "=&D" (__d0) \
+ : "r"(size & 3), "0"(size / 4), "1"(addr), "a"(0)); \
+} while (0)
+
+/**
+ * clear_user: - Zero a block of memory in user space.
+ * @to: Destination address, in user space.
+ * @n: Number of bytes to zero.
+ *
+ * Zero a block of memory in user space.
+ *
+ * Returns number of bytes that could not be cleared.
+ * On success, this will be zero.
+ */
+unsigned long
+clear_user(void __user *to, unsigned long n)
+{
+ might_fault();
+ if (access_ok(VERIFY_WRITE, to, n))
+ __do_clear_user(to, n);
+ return n;
+}
+EXPORT_SYMBOL(clear_user);
+
+/**
+ * __clear_user: - Zero a block of memory in user space, with less checking.
+ * @to: Destination address, in user space.
+ * @n: Number of bytes to zero.
+ *
+ * Zero a block of memory in user space. Caller must check
+ * the specified block with access_ok() before calling this function.
+ *
+ * Returns number of bytes that could not be cleared.
+ * On success, this will be zero.
+ */
+unsigned long
+__clear_user(void __user *to, unsigned long n)
+{
+ __do_clear_user(to, n);
+ return n;
+}
+EXPORT_SYMBOL(__clear_user);
+
+#ifdef CONFIG_X86_INTEL_USERCOPY
+static unsigned long
+__copy_user_intel(void __user *to, const void *from, unsigned long size)
+{
+ int d0, d1;
+ __asm__ __volatile__(
+ " .align 2,0x90\n"
+ "1: movl 32(%4), %%eax\n"
+ " cmpl $67, %0\n"
+ " jbe 3f\n"
+ "2: movl 64(%4), %%eax\n"
+ " .align 2,0x90\n"
+ "3: movl 0(%4), %%eax\n"
+ "4: movl 4(%4), %%edx\n"
+ "5: movl %%eax, 0(%3)\n"
+ "6: movl %%edx, 4(%3)\n"
+ "7: movl 8(%4), %%eax\n"
+ "8: movl 12(%4),%%edx\n"
+ "9: movl %%eax, 8(%3)\n"
+ "10: movl %%edx, 12(%3)\n"
+ "11: movl 16(%4), %%eax\n"
+ "12: movl 20(%4), %%edx\n"
+ "13: movl %%eax, 16(%3)\n"
+ "14: movl %%edx, 20(%3)\n"
+ "15: movl 24(%4), %%eax\n"
+ "16: movl 28(%4), %%edx\n"
+ "17: movl %%eax, 24(%3)\n"
+ "18: movl %%edx, 28(%3)\n"
+ "19: movl 32(%4), %%eax\n"
+ "20: movl 36(%4), %%edx\n"
+ "21: movl %%eax, 32(%3)\n"
+ "22: movl %%edx, 36(%3)\n"
+ "23: movl 40(%4), %%eax\n"
+ "24: movl 44(%4), %%edx\n"
+ "25: movl %%eax, 40(%3)\n"
+ "26: movl %%edx, 44(%3)\n"
+ "27: movl 48(%4), %%eax\n"
+ "28: movl 52(%4), %%edx\n"
+ "29: movl %%eax, 48(%3)\n"
+ "30: movl %%edx, 52(%3)\n"
+ "31: movl 56(%4), %%eax\n"
+ "32: movl 60(%4), %%edx\n"
+ "33: movl %%eax, 56(%3)\n"
+ "34: movl %%edx, 60(%3)\n"
+ " addl $-64, %0\n"
+ " addl $64, %4\n"
+ " addl $64, %3\n"
+ " cmpl $63, %0\n"
+ " ja 1b\n"
+ "35: movl %0, %%eax\n"
+ " shrl $2, %0\n"
+ " andl $3, %%eax\n"
+ " cld\n"
+ "99: rep; movsl\n"
+ "36: movl %%eax, %0\n"
+ "37: rep; movsb\n"
+ "100:\n"
+ ".section .fixup,\"ax\"\n"
+ "101: lea 0(%%eax,%0,4),%0\n"
+ " jmp 100b\n"
+ ".previous\n"
+ _ASM_EXTABLE(1b,100b)
+ _ASM_EXTABLE(2b,100b)
+ _ASM_EXTABLE(3b,100b)
+ _ASM_EXTABLE(4b,100b)
+ _ASM_EXTABLE(5b,100b)
+ _ASM_EXTABLE(6b,100b)
+ _ASM_EXTABLE(7b,100b)
+ _ASM_EXTABLE(8b,100b)
+ _ASM_EXTABLE(9b,100b)
+ _ASM_EXTABLE(10b,100b)
+ _ASM_EXTABLE(11b,100b)
+ _ASM_EXTABLE(12b,100b)
+ _ASM_EXTABLE(13b,100b)
+ _ASM_EXTABLE(14b,100b)
+ _ASM_EXTABLE(15b,100b)
+ _ASM_EXTABLE(16b,100b)
+ _ASM_EXTABLE(17b,100b)
+ _ASM_EXTABLE(18b,100b)
+ _ASM_EXTABLE(19b,100b)
+ _ASM_EXTABLE(20b,100b)
+ _ASM_EXTABLE(21b,100b)
+ _ASM_EXTABLE(22b,100b)
+ _ASM_EXTABLE(23b,100b)
+ _ASM_EXTABLE(24b,100b)
+ _ASM_EXTABLE(25b,100b)
+ _ASM_EXTABLE(26b,100b)
+ _ASM_EXTABLE(27b,100b)
+ _ASM_EXTABLE(28b,100b)
+ _ASM_EXTABLE(29b,100b)
+ _ASM_EXTABLE(30b,100b)
+ _ASM_EXTABLE(31b,100b)
+ _ASM_EXTABLE(32b,100b)
+ _ASM_EXTABLE(33b,100b)
+ _ASM_EXTABLE(34b,100b)
+ _ASM_EXTABLE(35b,100b)
+ _ASM_EXTABLE(36b,100b)
+ _ASM_EXTABLE(37b,100b)
+ _ASM_EXTABLE(99b,101b)
+ : "=&c"(size), "=&D" (d0), "=&S" (d1)
+ : "1"(to), "2"(from), "0"(size)
+ : "eax", "edx", "memory");
+ return size;
+}
+
+static unsigned long __copy_user_intel_nocache(void *to,
+ const void __user *from, unsigned long size)
+{
+ int d0, d1;
+
+ __asm__ __volatile__(
+ " .align 2,0x90\n"
+ "0: movl 32(%4), %%eax\n"
+ " cmpl $67, %0\n"
+ " jbe 2f\n"
+ "1: movl 64(%4), %%eax\n"
+ " .align 2,0x90\n"
+ "2: movl 0(%4), %%eax\n"
+ "21: movl 4(%4), %%edx\n"
+ " movnti %%eax, 0(%3)\n"
+ " movnti %%edx, 4(%3)\n"
+ "3: movl 8(%4), %%eax\n"
+ "31: movl 12(%4),%%edx\n"
+ " movnti %%eax, 8(%3)\n"
+ " movnti %%edx, 12(%3)\n"
+ "4: movl 16(%4), %%eax\n"
+ "41: movl 20(%4), %%edx\n"
+ " movnti %%eax, 16(%3)\n"
+ " movnti %%edx, 20(%3)\n"
+ "10: movl 24(%4), %%eax\n"
+ "51: movl 28(%4), %%edx\n"
+ " movnti %%eax, 24(%3)\n"
+ " movnti %%edx, 28(%3)\n"
+ "11: movl 32(%4), %%eax\n"
+ "61: movl 36(%4), %%edx\n"
+ " movnti %%eax, 32(%3)\n"
+ " movnti %%edx, 36(%3)\n"
+ "12: movl 40(%4), %%eax\n"
+ "71: movl 44(%4), %%edx\n"
+ " movnti %%eax, 40(%3)\n"
+ " movnti %%edx, 44(%3)\n"
+ "13: movl 48(%4), %%eax\n"
+ "81: movl 52(%4), %%edx\n"
+ " movnti %%eax, 48(%3)\n"
+ " movnti %%edx, 52(%3)\n"
+ "14: movl 56(%4), %%eax\n"
+ "91: movl 60(%4), %%edx\n"
+ " movnti %%eax, 56(%3)\n"
+ " movnti %%edx, 60(%3)\n"
+ " addl $-64, %0\n"
+ " addl $64, %4\n"
+ " addl $64, %3\n"
+ " cmpl $63, %0\n"
+ " ja 0b\n"
+ " sfence \n"
+ "5: movl %0, %%eax\n"
+ " shrl $2, %0\n"
+ " andl $3, %%eax\n"
+ " cld\n"
+ "6: rep; movsl\n"
+ " movl %%eax,%0\n"
+ "7: rep; movsb\n"
+ "8:\n"
+ ".section .fixup,\"ax\"\n"
+ "9: lea 0(%%eax,%0,4),%0\n"
+ "16: jmp 8b\n"
+ ".previous\n"
+ _ASM_EXTABLE(0b,16b)
+ _ASM_EXTABLE(1b,16b)
+ _ASM_EXTABLE(2b,16b)
+ _ASM_EXTABLE(21b,16b)
+ _ASM_EXTABLE(3b,16b)
+ _ASM_EXTABLE(31b,16b)
+ _ASM_EXTABLE(4b,16b)
+ _ASM_EXTABLE(41b,16b)
+ _ASM_EXTABLE(10b,16b)
+ _ASM_EXTABLE(51b,16b)
+ _ASM_EXTABLE(11b,16b)
+ _ASM_EXTABLE(61b,16b)
+ _ASM_EXTABLE(12b,16b)
+ _ASM_EXTABLE(71b,16b)
+ _ASM_EXTABLE(13b,16b)
+ _ASM_EXTABLE(81b,16b)
+ _ASM_EXTABLE(14b,16b)
+ _ASM_EXTABLE(91b,16b)
+ _ASM_EXTABLE(6b,9b)
+ _ASM_EXTABLE(7b,16b)
+ : "=&c"(size), "=&D" (d0), "=&S" (d1)
+ : "1"(to), "2"(from), "0"(size)
+ : "eax", "edx", "memory");
+ return size;
+}
+
+#else
+
+/*
+ * Leave these declared but undefined. They should not be any references to
+ * them
+ */
+unsigned long __copy_user_intel(void __user *to, const void *from,
+ unsigned long size);
+#endif /* CONFIG_X86_INTEL_USERCOPY */
+
+/* Generic arbitrary sized copy. */
+#define __copy_user(to, from, size) \
+do { \
+ int __d0, __d1, __d2; \
+ __asm__ __volatile__( \
+ " cmp $7,%0\n" \
+ " jbe 1f\n" \
+ " movl %1,%0\n" \
+ " negl %0\n" \
+ " andl $7,%0\n" \
+ " subl %0,%3\n" \
+ "4: rep; movsb\n" \
+ " movl %3,%0\n" \
+ " shrl $2,%0\n" \
+ " andl $3,%3\n" \
+ " .align 2,0x90\n" \
+ "0: rep; movsl\n" \
+ " movl %3,%0\n" \
+ "1: rep; movsb\n" \
+ "2:\n" \
+ ".section .fixup,\"ax\"\n" \
+ "5: addl %3,%0\n" \
+ " jmp 2b\n" \
+ "3: lea 0(%3,%0,4),%0\n" \
+ " jmp 2b\n" \
+ ".previous\n" \
+ _ASM_EXTABLE(4b,5b) \
+ _ASM_EXTABLE(0b,3b) \
+ _ASM_EXTABLE(1b,2b) \
+ : "=&c"(size), "=&D" (__d0), "=&S" (__d1), "=r"(__d2) \
+ : "3"(size), "0"(size), "1"(to), "2"(from) \
+ : "memory"); \
+} while (0)
+
+unsigned long __copy_user_ll(void *to, const void *from, unsigned long n)
+{
+ __uaccess_begin_nospec();
+ if (movsl_is_ok(to, from, n))
+ __copy_user(to, from, n);
+ else
+ n = __copy_user_intel(to, from, n);
+ __uaccess_end();
+ return n;
+}
+EXPORT_SYMBOL(__copy_user_ll);
+
+unsigned long __copy_from_user_ll_nocache_nozero(void *to, const void __user *from,
+ unsigned long n)
+{
+ __uaccess_begin_nospec();
+#ifdef CONFIG_X86_INTEL_USERCOPY
+ if (n > 64 && static_cpu_has(X86_FEATURE_XMM2))
+ n = __copy_user_intel_nocache(to, from, n);
+ else
+ __copy_user(to, from, n);
+#else
+ __copy_user(to, from, n);
+#endif
+ __uaccess_end();
+ return n;
+}
+EXPORT_SYMBOL(__copy_from_user_ll_nocache_nozero);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-01 23:26:47 +0000