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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /arch/x86/include/asm/page_64.h | |
parent | Initial commit. (diff) | |
download | linux-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/x86/include/asm/page_64.h')
-rw-r--r-- | arch/x86/include/asm/page_64.h | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/arch/x86/include/asm/page_64.h b/arch/x86/include/asm/page_64.h new file mode 100644 index 0000000000..cc6b8e0871 --- /dev/null +++ b/arch/x86/include/asm/page_64.h @@ -0,0 +1,102 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_X86_PAGE_64_H +#define _ASM_X86_PAGE_64_H + +#include <asm/page_64_types.h> + +#ifndef __ASSEMBLY__ +#include <asm/cpufeatures.h> +#include <asm/alternative.h> + +#include <linux/kmsan-checks.h> + +/* duplicated to the one in bootmem.h */ +extern unsigned long max_pfn; +extern unsigned long phys_base; + +extern unsigned long page_offset_base; +extern unsigned long vmalloc_base; +extern unsigned long vmemmap_base; + +static __always_inline unsigned long __phys_addr_nodebug(unsigned long x) +{ + unsigned long y = x - __START_KERNEL_map; + + /* use the carry flag to determine if x was < __START_KERNEL_map */ + x = y + ((x > y) ? phys_base : (__START_KERNEL_map - PAGE_OFFSET)); + + return x; +} + +#ifdef CONFIG_DEBUG_VIRTUAL +extern unsigned long __phys_addr(unsigned long); +extern unsigned long __phys_addr_symbol(unsigned long); +#else +#define __phys_addr(x) __phys_addr_nodebug(x) +#define __phys_addr_symbol(x) \ + ((unsigned long)(x) - __START_KERNEL_map + phys_base) +#endif + +#define __phys_reloc_hide(x) (x) + +void clear_page_orig(void *page); +void clear_page_rep(void *page); +void clear_page_erms(void *page); + +static inline void clear_page(void *page) +{ + /* + * Clean up KMSAN metadata for the page being cleared. The assembly call + * below clobbers @page, so we perform unpoisoning before it. + */ + kmsan_unpoison_memory(page, PAGE_SIZE); + alternative_call_2(clear_page_orig, + clear_page_rep, X86_FEATURE_REP_GOOD, + clear_page_erms, X86_FEATURE_ERMS, + "=D" (page), + "0" (page) + : "cc", "memory", "rax", "rcx"); +} + +void copy_page(void *to, void *from); + +#ifdef CONFIG_X86_5LEVEL +/* + * User space process size. This is the first address outside the user range. + * There are a few constraints that determine this: + * + * On Intel CPUs, if a SYSCALL instruction is at the highest canonical + * address, then that syscall will enter the kernel with a + * non-canonical return address, and SYSRET will explode dangerously. + * We avoid this particular problem by preventing anything + * from being mapped at the maximum canonical address. + * + * On AMD CPUs in the Ryzen family, there's a nasty bug in which the + * CPUs malfunction if they execute code from the highest canonical page. + * They'll speculate right off the end of the canonical space, and + * bad things happen. This is worked around in the same way as the + * Intel problem. + * + * With page table isolation enabled, we map the LDT in ... [stay tuned] + */ +static __always_inline unsigned long task_size_max(void) +{ + unsigned long ret; + + alternative_io("movq %[small],%0","movq %[large],%0", + X86_FEATURE_LA57, + "=r" (ret), + [small] "i" ((1ul << 47)-PAGE_SIZE), + [large] "i" ((1ul << 56)-PAGE_SIZE)); + + return ret; +} +#endif /* CONFIG_X86_5LEVEL */ + +#endif /* !__ASSEMBLY__ */ + +#ifdef CONFIG_X86_VSYSCALL_EMULATION +# define __HAVE_ARCH_GATE_AREA 1 +#endif + +#endif /* _ASM_X86_PAGE_64_H */ |