| // 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/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" \ | |
| _ASM_EXTABLE_TYPE_REG(0b, 2b, EX_TYPE_UCOPY_LEN4, %2) \ | |
| _ASM_EXTABLE_UA(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. | |
| * | |
| * Return: 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(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. | |
| * | |
| * Return: 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" | |
| _ASM_EXTABLE_UA(1b, 100b) | |
| _ASM_EXTABLE_UA(2b, 100b) | |
| _ASM_EXTABLE_UA(3b, 100b) | |
| _ASM_EXTABLE_UA(4b, 100b) | |
| _ASM_EXTABLE_UA(5b, 100b) | |
| _ASM_EXTABLE_UA(6b, 100b) | |
| _ASM_EXTABLE_UA(7b, 100b) | |
| _ASM_EXTABLE_UA(8b, 100b) | |
| _ASM_EXTABLE_UA(9b, 100b) | |
| _ASM_EXTABLE_UA(10b, 100b) | |
| _ASM_EXTABLE_UA(11b, 100b) | |
| _ASM_EXTABLE_UA(12b, 100b) | |
| _ASM_EXTABLE_UA(13b, 100b) | |
| _ASM_EXTABLE_UA(14b, 100b) | |
| _ASM_EXTABLE_UA(15b, 100b) | |
| _ASM_EXTABLE_UA(16b, 100b) | |
| _ASM_EXTABLE_UA(17b, 100b) | |
| _ASM_EXTABLE_UA(18b, 100b) | |
| _ASM_EXTABLE_UA(19b, 100b) | |
| _ASM_EXTABLE_UA(20b, 100b) | |
| _ASM_EXTABLE_UA(21b, 100b) | |
| _ASM_EXTABLE_UA(22b, 100b) | |
| _ASM_EXTABLE_UA(23b, 100b) | |
| _ASM_EXTABLE_UA(24b, 100b) | |
| _ASM_EXTABLE_UA(25b, 100b) | |
| _ASM_EXTABLE_UA(26b, 100b) | |
| _ASM_EXTABLE_UA(27b, 100b) | |
| _ASM_EXTABLE_UA(28b, 100b) | |
| _ASM_EXTABLE_UA(29b, 100b) | |
| _ASM_EXTABLE_UA(30b, 100b) | |
| _ASM_EXTABLE_UA(31b, 100b) | |
| _ASM_EXTABLE_UA(32b, 100b) | |
| _ASM_EXTABLE_UA(33b, 100b) | |
| _ASM_EXTABLE_UA(34b, 100b) | |
| _ASM_EXTABLE_UA(35b, 100b) | |
| _ASM_EXTABLE_UA(36b, 100b) | |
| _ASM_EXTABLE_UA(37b, 100b) | |
| _ASM_EXTABLE_TYPE_REG(99b, 100b, EX_TYPE_UCOPY_LEN4, %%eax) | |
| : "=&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" | |
| _ASM_EXTABLE_UA(0b, 8b) | |
| _ASM_EXTABLE_UA(1b, 8b) | |
| _ASM_EXTABLE_UA(2b, 8b) | |
| _ASM_EXTABLE_UA(21b, 8b) | |
| _ASM_EXTABLE_UA(3b, 8b) | |
| _ASM_EXTABLE_UA(31b, 8b) | |
| _ASM_EXTABLE_UA(4b, 8b) | |
| _ASM_EXTABLE_UA(41b, 8b) | |
| _ASM_EXTABLE_UA(10b, 8b) | |
| _ASM_EXTABLE_UA(51b, 8b) | |
| _ASM_EXTABLE_UA(11b, 8b) | |
| _ASM_EXTABLE_UA(61b, 8b) | |
| _ASM_EXTABLE_UA(12b, 8b) | |
| _ASM_EXTABLE_UA(71b, 8b) | |
| _ASM_EXTABLE_UA(13b, 8b) | |
| _ASM_EXTABLE_UA(81b, 8b) | |
| _ASM_EXTABLE_UA(14b, 8b) | |
| _ASM_EXTABLE_UA(91b, 8b) | |
| _ASM_EXTABLE_TYPE_REG(6b, 8b, EX_TYPE_UCOPY_LEN4, %%eax) | |
| _ASM_EXTABLE_UA(7b, 8b) | |
| : "=&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" \ | |
| _ASM_EXTABLE_TYPE_REG(4b, 2b, EX_TYPE_UCOPY_LEN1, %3) \ | |
| _ASM_EXTABLE_TYPE_REG(0b, 2b, EX_TYPE_UCOPY_LEN4, %3) \ | |
| _ASM_EXTABLE_UA(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_inatomic_nontemporal(void *to, const void __user *from, | |
| unsigned long n) | |
| { | |
| if (!user_access_begin(from, n)) | |
| return n; | |
| #ifdef CONFIG_X86_INTEL_USERCOPY | |
| if (n > 64 && cpu_feature_enabled(X86_FEATURE_XMM2)) | |
| n = __copy_user_intel_nocache(to, from, n); | |
| else | |
| __copy_user(to, from, n); | |
| #else | |
| __copy_user(to, from, n); | |
| #endif | |
| user_access_end(); | |
| return n; | |
| } | |
| EXPORT_SYMBOL(copy_from_user_inatomic_nontemporal); |