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2315 lines
56 KiB
2315 lines
56 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* Copyright 2002 Andi Kleen, SuSE Labs. |
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* Thanks to Ben LaHaise for precious feedback. |
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*/ |
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#include <linux/highmem.h> |
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#include <linux/memblock.h> |
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#include <linux/sched.h> |
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#include <linux/mm.h> |
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#include <linux/interrupt.h> |
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#include <linux/seq_file.h> |
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#include <linux/debugfs.h> |
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#include <linux/pfn.h> |
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#include <linux/percpu.h> |
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#include <linux/gfp.h> |
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#include <linux/pci.h> |
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#include <linux/vmalloc.h> |
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#include <linux/libnvdimm.h> |
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|
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#include <asm/e820/api.h> |
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#include <asm/processor.h> |
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#include <asm/tlbflush.h> |
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#include <asm/sections.h> |
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#include <asm/setup.h> |
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#include <linux/uaccess.h> |
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#include <asm/pgalloc.h> |
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#include <asm/proto.h> |
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#include <asm/memtype.h> |
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#include <asm/set_memory.h> |
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|
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#include "../mm_internal.h" |
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|
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/* |
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* The current flushing context - we pass it instead of 5 arguments: |
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*/ |
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struct cpa_data { |
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unsigned long *vaddr; |
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pgd_t *pgd; |
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pgprot_t mask_set; |
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pgprot_t mask_clr; |
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unsigned long numpages; |
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unsigned long curpage; |
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unsigned long pfn; |
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unsigned int flags; |
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unsigned int force_split : 1, |
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force_static_prot : 1, |
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force_flush_all : 1; |
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struct page **pages; |
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}; |
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enum cpa_warn { |
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CPA_CONFLICT, |
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CPA_PROTECT, |
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CPA_DETECT, |
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}; |
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|
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static const int cpa_warn_level = CPA_PROTECT; |
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|
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/* |
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* Serialize cpa() (for !DEBUG_PAGEALLOC which uses large identity mappings) |
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* using cpa_lock. So that we don't allow any other cpu, with stale large tlb |
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* entries change the page attribute in parallel to some other cpu |
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* splitting a large page entry along with changing the attribute. |
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*/ |
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static DEFINE_SPINLOCK(cpa_lock); |
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|
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#define CPA_FLUSHTLB 1 |
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#define CPA_ARRAY 2 |
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#define CPA_PAGES_ARRAY 4 |
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#define CPA_NO_CHECK_ALIAS 8 /* Do not search for aliases */ |
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|
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static inline pgprot_t cachemode2pgprot(enum page_cache_mode pcm) |
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{ |
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return __pgprot(cachemode2protval(pcm)); |
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} |
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|
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#ifdef CONFIG_PROC_FS |
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static unsigned long direct_pages_count[PG_LEVEL_NUM]; |
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|
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void update_page_count(int level, unsigned long pages) |
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{ |
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/* Protect against CPA */ |
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spin_lock(&pgd_lock); |
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direct_pages_count[level] += pages; |
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spin_unlock(&pgd_lock); |
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} |
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|
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static void split_page_count(int level) |
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{ |
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if (direct_pages_count[level] == 0) |
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return; |
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|
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direct_pages_count[level]--; |
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direct_pages_count[level - 1] += PTRS_PER_PTE; |
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} |
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|
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void arch_report_meminfo(struct seq_file *m) |
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{ |
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seq_printf(m, "DirectMap4k: %8lu kB\n", |
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direct_pages_count[PG_LEVEL_4K] << 2); |
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#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE) |
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seq_printf(m, "DirectMap2M: %8lu kB\n", |
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direct_pages_count[PG_LEVEL_2M] << 11); |
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#else |
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seq_printf(m, "DirectMap4M: %8lu kB\n", |
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direct_pages_count[PG_LEVEL_2M] << 12); |
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#endif |
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if (direct_gbpages) |
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seq_printf(m, "DirectMap1G: %8lu kB\n", |
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direct_pages_count[PG_LEVEL_1G] << 20); |
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} |
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#else |
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static inline void split_page_count(int level) { } |
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#endif |
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|
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#ifdef CONFIG_X86_CPA_STATISTICS |
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|
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static unsigned long cpa_1g_checked; |
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static unsigned long cpa_1g_sameprot; |
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static unsigned long cpa_1g_preserved; |
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static unsigned long cpa_2m_checked; |
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static unsigned long cpa_2m_sameprot; |
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static unsigned long cpa_2m_preserved; |
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static unsigned long cpa_4k_install; |
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|
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static inline void cpa_inc_1g_checked(void) |
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{ |
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cpa_1g_checked++; |
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} |
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|
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static inline void cpa_inc_2m_checked(void) |
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{ |
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cpa_2m_checked++; |
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} |
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|
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static inline void cpa_inc_4k_install(void) |
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{ |
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data_race(cpa_4k_install++); |
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} |
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|
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static inline void cpa_inc_lp_sameprot(int level) |
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{ |
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if (level == PG_LEVEL_1G) |
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cpa_1g_sameprot++; |
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else |
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cpa_2m_sameprot++; |
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} |
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|
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static inline void cpa_inc_lp_preserved(int level) |
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{ |
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if (level == PG_LEVEL_1G) |
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cpa_1g_preserved++; |
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else |
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cpa_2m_preserved++; |
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} |
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|
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static int cpastats_show(struct seq_file *m, void *p) |
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{ |
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seq_printf(m, "1G pages checked: %16lu\n", cpa_1g_checked); |
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seq_printf(m, "1G pages sameprot: %16lu\n", cpa_1g_sameprot); |
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seq_printf(m, "1G pages preserved: %16lu\n", cpa_1g_preserved); |
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seq_printf(m, "2M pages checked: %16lu\n", cpa_2m_checked); |
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seq_printf(m, "2M pages sameprot: %16lu\n", cpa_2m_sameprot); |
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seq_printf(m, "2M pages preserved: %16lu\n", cpa_2m_preserved); |
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seq_printf(m, "4K pages set-checked: %16lu\n", cpa_4k_install); |
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return 0; |
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} |
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|
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static int cpastats_open(struct inode *inode, struct file *file) |
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{ |
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return single_open(file, cpastats_show, NULL); |
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} |
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|
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static const struct file_operations cpastats_fops = { |
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.open = cpastats_open, |
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.read = seq_read, |
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.llseek = seq_lseek, |
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.release = single_release, |
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}; |
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|
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static int __init cpa_stats_init(void) |
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{ |
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debugfs_create_file("cpa_stats", S_IRUSR, arch_debugfs_dir, NULL, |
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&cpastats_fops); |
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return 0; |
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} |
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late_initcall(cpa_stats_init); |
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#else |
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static inline void cpa_inc_1g_checked(void) { } |
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static inline void cpa_inc_2m_checked(void) { } |
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static inline void cpa_inc_4k_install(void) { } |
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static inline void cpa_inc_lp_sameprot(int level) { } |
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static inline void cpa_inc_lp_preserved(int level) { } |
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#endif |
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static inline int |
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within(unsigned long addr, unsigned long start, unsigned long end) |
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{ |
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return addr >= start && addr < end; |
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} |
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|
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static inline int |
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within_inclusive(unsigned long addr, unsigned long start, unsigned long end) |
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{ |
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return addr >= start && addr <= end; |
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} |
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|
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#ifdef CONFIG_X86_64 |
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|
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static inline unsigned long highmap_start_pfn(void) |
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{ |
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return __pa_symbol(_text) >> PAGE_SHIFT; |
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} |
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|
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static inline unsigned long highmap_end_pfn(void) |
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{ |
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/* Do not reference physical address outside the kernel. */ |
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return __pa_symbol(roundup(_brk_end, PMD_SIZE) - 1) >> PAGE_SHIFT; |
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} |
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static bool __cpa_pfn_in_highmap(unsigned long pfn) |
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{ |
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/* |
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* Kernel text has an alias mapping at a high address, known |
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* here as "highmap". |
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*/ |
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return within_inclusive(pfn, highmap_start_pfn(), highmap_end_pfn()); |
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} |
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#else |
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static bool __cpa_pfn_in_highmap(unsigned long pfn) |
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{ |
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/* There is no highmap on 32-bit */ |
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return false; |
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} |
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|
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#endif |
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|
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/* |
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* See set_mce_nospec(). |
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* |
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* Machine check recovery code needs to change cache mode of poisoned pages to |
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* UC to avoid speculative access logging another error. But passing the |
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* address of the 1:1 mapping to set_memory_uc() is a fine way to encourage a |
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* speculative access. So we cheat and flip the top bit of the address. This |
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* works fine for the code that updates the page tables. But at the end of the |
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* process we need to flush the TLB and cache and the non-canonical address |
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* causes a #GP fault when used by the INVLPG and CLFLUSH instructions. |
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* |
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* But in the common case we already have a canonical address. This code |
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* will fix the top bit if needed and is a no-op otherwise. |
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*/ |
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static inline unsigned long fix_addr(unsigned long addr) |
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{ |
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#ifdef CONFIG_X86_64 |
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return (long)(addr << 1) >> 1; |
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#else |
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return addr; |
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#endif |
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} |
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static unsigned long __cpa_addr(struct cpa_data *cpa, unsigned long idx) |
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{ |
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if (cpa->flags & CPA_PAGES_ARRAY) { |
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struct page *page = cpa->pages[idx]; |
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|
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if (unlikely(PageHighMem(page))) |
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return 0; |
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return (unsigned long)page_address(page); |
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} |
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if (cpa->flags & CPA_ARRAY) |
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return cpa->vaddr[idx]; |
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return *cpa->vaddr + idx * PAGE_SIZE; |
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} |
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|
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/* |
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* Flushing functions |
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*/ |
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|
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static void clflush_cache_range_opt(void *vaddr, unsigned int size) |
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{ |
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const unsigned long clflush_size = boot_cpu_data.x86_clflush_size; |
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void *p = (void *)((unsigned long)vaddr & ~(clflush_size - 1)); |
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void *vend = vaddr + size; |
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|
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if (p >= vend) |
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return; |
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|
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for (; p < vend; p += clflush_size) |
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clflushopt(p); |
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} |
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|
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/** |
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* clflush_cache_range - flush a cache range with clflush |
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* @vaddr: virtual start address |
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* @size: number of bytes to flush |
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* |
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* CLFLUSHOPT is an unordered instruction which needs fencing with MFENCE or |
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* SFENCE to avoid ordering issues. |
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*/ |
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void clflush_cache_range(void *vaddr, unsigned int size) |
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{ |
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mb(); |
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clflush_cache_range_opt(vaddr, size); |
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mb(); |
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} |
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EXPORT_SYMBOL_GPL(clflush_cache_range); |
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|
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#ifdef CONFIG_ARCH_HAS_PMEM_API |
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void arch_invalidate_pmem(void *addr, size_t size) |
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{ |
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clflush_cache_range(addr, size); |
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} |
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EXPORT_SYMBOL_GPL(arch_invalidate_pmem); |
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#endif |
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|
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static void __cpa_flush_all(void *arg) |
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{ |
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unsigned long cache = (unsigned long)arg; |
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|
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/* |
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* Flush all to work around Errata in early athlons regarding |
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* large page flushing. |
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*/ |
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__flush_tlb_all(); |
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|
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if (cache && boot_cpu_data.x86 >= 4) |
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wbinvd(); |
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} |
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|
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static void cpa_flush_all(unsigned long cache) |
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{ |
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BUG_ON(irqs_disabled() && !early_boot_irqs_disabled); |
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|
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on_each_cpu(__cpa_flush_all, (void *) cache, 1); |
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} |
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static void __cpa_flush_tlb(void *data) |
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{ |
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struct cpa_data *cpa = data; |
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unsigned int i; |
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for (i = 0; i < cpa->numpages; i++) |
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flush_tlb_one_kernel(fix_addr(__cpa_addr(cpa, i))); |
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} |
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|
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static void cpa_flush(struct cpa_data *data, int cache) |
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{ |
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struct cpa_data *cpa = data; |
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unsigned int i; |
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|
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BUG_ON(irqs_disabled() && !early_boot_irqs_disabled); |
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if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) { |
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cpa_flush_all(cache); |
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return; |
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} |
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|
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if (cpa->force_flush_all || cpa->numpages > tlb_single_page_flush_ceiling) |
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flush_tlb_all(); |
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else |
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on_each_cpu(__cpa_flush_tlb, cpa, 1); |
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|
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if (!cache) |
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return; |
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|
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mb(); |
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for (i = 0; i < cpa->numpages; i++) { |
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unsigned long addr = __cpa_addr(cpa, i); |
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unsigned int level; |
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|
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pte_t *pte = lookup_address(addr, &level); |
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|
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/* |
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* Only flush present addresses: |
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*/ |
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if (pte && (pte_val(*pte) & _PAGE_PRESENT)) |
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clflush_cache_range_opt((void *)fix_addr(addr), PAGE_SIZE); |
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} |
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mb(); |
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} |
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static bool overlaps(unsigned long r1_start, unsigned long r1_end, |
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unsigned long r2_start, unsigned long r2_end) |
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{ |
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return (r1_start <= r2_end && r1_end >= r2_start) || |
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(r2_start <= r1_end && r2_end >= r1_start); |
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} |
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|
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#ifdef CONFIG_PCI_BIOS |
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/* |
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* The BIOS area between 640k and 1Mb needs to be executable for PCI BIOS |
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* based config access (CONFIG_PCI_GOBIOS) support. |
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*/ |
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#define BIOS_PFN PFN_DOWN(BIOS_BEGIN) |
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#define BIOS_PFN_END PFN_DOWN(BIOS_END - 1) |
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|
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static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn) |
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{ |
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if (pcibios_enabled && overlaps(spfn, epfn, BIOS_PFN, BIOS_PFN_END)) |
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return _PAGE_NX; |
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return 0; |
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} |
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#else |
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static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn) |
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{ |
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return 0; |
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} |
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#endif |
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|
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/* |
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* The .rodata section needs to be read-only. Using the pfn catches all |
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* aliases. This also includes __ro_after_init, so do not enforce until |
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* kernel_set_to_readonly is true. |
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*/ |
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static pgprotval_t protect_rodata(unsigned long spfn, unsigned long epfn) |
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{ |
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unsigned long epfn_ro, spfn_ro = PFN_DOWN(__pa_symbol(__start_rodata)); |
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|
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/* |
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* Note: __end_rodata is at page aligned and not inclusive, so |
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* subtract 1 to get the last enforced PFN in the rodata area. |
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*/ |
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epfn_ro = PFN_DOWN(__pa_symbol(__end_rodata)) - 1; |
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|
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if (kernel_set_to_readonly && overlaps(spfn, epfn, spfn_ro, epfn_ro)) |
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return _PAGE_RW; |
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return 0; |
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} |
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|
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/* |
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* Protect kernel text against becoming non executable by forbidding |
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* _PAGE_NX. This protects only the high kernel mapping (_text -> _etext) |
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* out of which the kernel actually executes. Do not protect the low |
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* mapping. |
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* |
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* This does not cover __inittext since that is gone after boot. |
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*/ |
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static pgprotval_t protect_kernel_text(unsigned long start, unsigned long end) |
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{ |
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unsigned long t_end = (unsigned long)_etext - 1; |
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unsigned long t_start = (unsigned long)_text; |
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|
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if (overlaps(start, end, t_start, t_end)) |
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return _PAGE_NX; |
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return 0; |
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} |
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|
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#if defined(CONFIG_X86_64) |
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/* |
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* Once the kernel maps the text as RO (kernel_set_to_readonly is set), |
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* kernel text mappings for the large page aligned text, rodata sections |
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* will be always read-only. For the kernel identity mappings covering the |
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* holes caused by this alignment can be anything that user asks. |
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* |
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* This will preserve the large page mappings for kernel text/data at no |
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* extra cost. |
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*/ |
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static pgprotval_t protect_kernel_text_ro(unsigned long start, |
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unsigned long end) |
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{ |
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unsigned long t_end = (unsigned long)__end_rodata_hpage_align - 1; |
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unsigned long t_start = (unsigned long)_text; |
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unsigned int level; |
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|
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if (!kernel_set_to_readonly || !overlaps(start, end, t_start, t_end)) |
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return 0; |
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/* |
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* Don't enforce the !RW mapping for the kernel text mapping, if |
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* the current mapping is already using small page mapping. No |
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* need to work hard to preserve large page mappings in this case. |
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* |
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* This also fixes the Linux Xen paravirt guest boot failure caused |
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* by unexpected read-only mappings for kernel identity |
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* mappings. In this paravirt guest case, the kernel text mapping |
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* and the kernel identity mapping share the same page-table pages, |
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* so the protections for kernel text and identity mappings have to |
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* be the same. |
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*/ |
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if (lookup_address(start, &level) && (level != PG_LEVEL_4K)) |
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return _PAGE_RW; |
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return 0; |
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} |
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#else |
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static pgprotval_t protect_kernel_text_ro(unsigned long start, |
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unsigned long end) |
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{ |
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return 0; |
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} |
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#endif |
|
|
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static inline bool conflicts(pgprot_t prot, pgprotval_t val) |
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{ |
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return (pgprot_val(prot) & ~val) != pgprot_val(prot); |
|
} |
|
|
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static inline void check_conflict(int warnlvl, pgprot_t prot, pgprotval_t val, |
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unsigned long start, unsigned long end, |
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unsigned long pfn, const char *txt) |
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{ |
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static const char *lvltxt[] = { |
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[CPA_CONFLICT] = "conflict", |
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[CPA_PROTECT] = "protect", |
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[CPA_DETECT] = "detect", |
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}; |
|
|
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if (warnlvl > cpa_warn_level || !conflicts(prot, val)) |
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return; |
|
|
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pr_warn("CPA %8s %10s: 0x%016lx - 0x%016lx PFN %lx req %016llx prevent %016llx\n", |
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lvltxt[warnlvl], txt, start, end, pfn, (unsigned long long)pgprot_val(prot), |
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(unsigned long long)val); |
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} |
|
|
|
/* |
|
* Certain areas of memory on x86 require very specific protection flags, |
|
* for example the BIOS area or kernel text. Callers don't always get this |
|
* right (again, ioremap() on BIOS memory is not uncommon) so this function |
|
* checks and fixes these known static required protection bits. |
|
*/ |
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static inline pgprot_t static_protections(pgprot_t prot, unsigned long start, |
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unsigned long pfn, unsigned long npg, |
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unsigned long lpsize, int warnlvl) |
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{ |
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pgprotval_t forbidden, res; |
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unsigned long end; |
|
|
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/* |
|
* There is no point in checking RW/NX conflicts when the requested |
|
* mapping is setting the page !PRESENT. |
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*/ |
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if (!(pgprot_val(prot) & _PAGE_PRESENT)) |
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return prot; |
|
|
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/* Operate on the virtual address */ |
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end = start + npg * PAGE_SIZE - 1; |
|
|
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res = protect_kernel_text(start, end); |
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check_conflict(warnlvl, prot, res, start, end, pfn, "Text NX"); |
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forbidden = res; |
|
|
|
/* |
|
* Special case to preserve a large page. If the change spawns the |
|
* full large page mapping then there is no point to split it |
|
* up. Happens with ftrace and is going to be removed once ftrace |
|
* switched to text_poke(). |
|
*/ |
|
if (lpsize != (npg * PAGE_SIZE) || (start & (lpsize - 1))) { |
|
res = protect_kernel_text_ro(start, end); |
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check_conflict(warnlvl, prot, res, start, end, pfn, "Text RO"); |
|
forbidden |= res; |
|
} |
|
|
|
/* Check the PFN directly */ |
|
res = protect_pci_bios(pfn, pfn + npg - 1); |
|
check_conflict(warnlvl, prot, res, start, end, pfn, "PCIBIOS NX"); |
|
forbidden |= res; |
|
|
|
res = protect_rodata(pfn, pfn + npg - 1); |
|
check_conflict(warnlvl, prot, res, start, end, pfn, "Rodata RO"); |
|
forbidden |= res; |
|
|
|
return __pgprot(pgprot_val(prot) & ~forbidden); |
|
} |
|
|
|
/* |
|
* Lookup the page table entry for a virtual address in a specific pgd. |
|
* Return a pointer to the entry and the level of the mapping. |
|
*/ |
|
pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address, |
|
unsigned int *level) |
|
{ |
|
p4d_t *p4d; |
|
pud_t *pud; |
|
pmd_t *pmd; |
|
|
|
*level = PG_LEVEL_NONE; |
|
|
|
if (pgd_none(*pgd)) |
|
return NULL; |
|
|
|
p4d = p4d_offset(pgd, address); |
|
if (p4d_none(*p4d)) |
|
return NULL; |
|
|
|
*level = PG_LEVEL_512G; |
|
if (p4d_large(*p4d) || !p4d_present(*p4d)) |
|
return (pte_t *)p4d; |
|
|
|
pud = pud_offset(p4d, address); |
|
if (pud_none(*pud)) |
|
return NULL; |
|
|
|
*level = PG_LEVEL_1G; |
|
if (pud_large(*pud) || !pud_present(*pud)) |
|
return (pte_t *)pud; |
|
|
|
pmd = pmd_offset(pud, address); |
|
if (pmd_none(*pmd)) |
|
return NULL; |
|
|
|
*level = PG_LEVEL_2M; |
|
if (pmd_large(*pmd) || !pmd_present(*pmd)) |
|
return (pte_t *)pmd; |
|
|
|
*level = PG_LEVEL_4K; |
|
|
|
return pte_offset_kernel(pmd, address); |
|
} |
|
|
|
/* |
|
* Lookup the page table entry for a virtual address. Return a pointer |
|
* to the entry and the level of the mapping. |
|
* |
|
* Note: We return pud and pmd either when the entry is marked large |
|
* or when the present bit is not set. Otherwise we would return a |
|
* pointer to a nonexisting mapping. |
|
*/ |
|
pte_t *lookup_address(unsigned long address, unsigned int *level) |
|
{ |
|
return lookup_address_in_pgd(pgd_offset_k(address), address, level); |
|
} |
|
EXPORT_SYMBOL_GPL(lookup_address); |
|
|
|
/* |
|
* Lookup the page table entry for a virtual address in a given mm. Return a |
|
* pointer to the entry and the level of the mapping. |
|
*/ |
|
pte_t *lookup_address_in_mm(struct mm_struct *mm, unsigned long address, |
|
unsigned int *level) |
|
{ |
|
return lookup_address_in_pgd(pgd_offset(mm, address), address, level); |
|
} |
|
EXPORT_SYMBOL_GPL(lookup_address_in_mm); |
|
|
|
static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address, |
|
unsigned int *level) |
|
{ |
|
if (cpa->pgd) |
|
return lookup_address_in_pgd(cpa->pgd + pgd_index(address), |
|
address, level); |
|
|
|
return lookup_address(address, level); |
|
} |
|
|
|
/* |
|
* Lookup the PMD entry for a virtual address. Return a pointer to the entry |
|
* or NULL if not present. |
|
*/ |
|
pmd_t *lookup_pmd_address(unsigned long address) |
|
{ |
|
pgd_t *pgd; |
|
p4d_t *p4d; |
|
pud_t *pud; |
|
|
|
pgd = pgd_offset_k(address); |
|
if (pgd_none(*pgd)) |
|
return NULL; |
|
|
|
p4d = p4d_offset(pgd, address); |
|
if (p4d_none(*p4d) || p4d_large(*p4d) || !p4d_present(*p4d)) |
|
return NULL; |
|
|
|
pud = pud_offset(p4d, address); |
|
if (pud_none(*pud) || pud_large(*pud) || !pud_present(*pud)) |
|
return NULL; |
|
|
|
return pmd_offset(pud, address); |
|
} |
|
|
|
/* |
|
* This is necessary because __pa() does not work on some |
|
* kinds of memory, like vmalloc() or the alloc_remap() |
|
* areas on 32-bit NUMA systems. The percpu areas can |
|
* end up in this kind of memory, for instance. |
|
* |
|
* This could be optimized, but it is only intended to be |
|
* used at inititalization time, and keeping it |
|
* unoptimized should increase the testing coverage for |
|
* the more obscure platforms. |
|
*/ |
|
phys_addr_t slow_virt_to_phys(void *__virt_addr) |
|
{ |
|
unsigned long virt_addr = (unsigned long)__virt_addr; |
|
phys_addr_t phys_addr; |
|
unsigned long offset; |
|
enum pg_level level; |
|
pte_t *pte; |
|
|
|
pte = lookup_address(virt_addr, &level); |
|
BUG_ON(!pte); |
|
|
|
/* |
|
* pXX_pfn() returns unsigned long, which must be cast to phys_addr_t |
|
* before being left-shifted PAGE_SHIFT bits -- this trick is to |
|
* make 32-PAE kernel work correctly. |
|
*/ |
|
switch (level) { |
|
case PG_LEVEL_1G: |
|
phys_addr = (phys_addr_t)pud_pfn(*(pud_t *)pte) << PAGE_SHIFT; |
|
offset = virt_addr & ~PUD_PAGE_MASK; |
|
break; |
|
case PG_LEVEL_2M: |
|
phys_addr = (phys_addr_t)pmd_pfn(*(pmd_t *)pte) << PAGE_SHIFT; |
|
offset = virt_addr & ~PMD_PAGE_MASK; |
|
break; |
|
default: |
|
phys_addr = (phys_addr_t)pte_pfn(*pte) << PAGE_SHIFT; |
|
offset = virt_addr & ~PAGE_MASK; |
|
} |
|
|
|
return (phys_addr_t)(phys_addr | offset); |
|
} |
|
EXPORT_SYMBOL_GPL(slow_virt_to_phys); |
|
|
|
/* |
|
* Set the new pmd in all the pgds we know about: |
|
*/ |
|
static void __set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte) |
|
{ |
|
/* change init_mm */ |
|
set_pte_atomic(kpte, pte); |
|
#ifdef CONFIG_X86_32 |
|
if (!SHARED_KERNEL_PMD) { |
|
struct page *page; |
|
|
|
list_for_each_entry(page, &pgd_list, lru) { |
|
pgd_t *pgd; |
|
p4d_t *p4d; |
|
pud_t *pud; |
|
pmd_t *pmd; |
|
|
|
pgd = (pgd_t *)page_address(page) + pgd_index(address); |
|
p4d = p4d_offset(pgd, address); |
|
pud = pud_offset(p4d, address); |
|
pmd = pmd_offset(pud, address); |
|
set_pte_atomic((pte_t *)pmd, pte); |
|
} |
|
} |
|
#endif |
|
} |
|
|
|
static pgprot_t pgprot_clear_protnone_bits(pgprot_t prot) |
|
{ |
|
/* |
|
* _PAGE_GLOBAL means "global page" for present PTEs. |
|
* But, it is also used to indicate _PAGE_PROTNONE |
|
* for non-present PTEs. |
|
* |
|
* This ensures that a _PAGE_GLOBAL PTE going from |
|
* present to non-present is not confused as |
|
* _PAGE_PROTNONE. |
|
*/ |
|
if (!(pgprot_val(prot) & _PAGE_PRESENT)) |
|
pgprot_val(prot) &= ~_PAGE_GLOBAL; |
|
|
|
return prot; |
|
} |
|
|
|
static int __should_split_large_page(pte_t *kpte, unsigned long address, |
|
struct cpa_data *cpa) |
|
{ |
|
unsigned long numpages, pmask, psize, lpaddr, pfn, old_pfn; |
|
pgprot_t old_prot, new_prot, req_prot, chk_prot; |
|
pte_t new_pte, *tmp; |
|
enum pg_level level; |
|
|
|
/* |
|
* Check for races, another CPU might have split this page |
|
* up already: |
|
*/ |
|
tmp = _lookup_address_cpa(cpa, address, &level); |
|
if (tmp != kpte) |
|
return 1; |
|
|
|
switch (level) { |
|
case PG_LEVEL_2M: |
|
old_prot = pmd_pgprot(*(pmd_t *)kpte); |
|
old_pfn = pmd_pfn(*(pmd_t *)kpte); |
|
cpa_inc_2m_checked(); |
|
break; |
|
case PG_LEVEL_1G: |
|
old_prot = pud_pgprot(*(pud_t *)kpte); |
|
old_pfn = pud_pfn(*(pud_t *)kpte); |
|
cpa_inc_1g_checked(); |
|
break; |
|
default: |
|
return -EINVAL; |
|
} |
|
|
|
psize = page_level_size(level); |
|
pmask = page_level_mask(level); |
|
|
|
/* |
|
* Calculate the number of pages, which fit into this large |
|
* page starting at address: |
|
*/ |
|
lpaddr = (address + psize) & pmask; |
|
numpages = (lpaddr - address) >> PAGE_SHIFT; |
|
if (numpages < cpa->numpages) |
|
cpa->numpages = numpages; |
|
|
|
/* |
|
* We are safe now. Check whether the new pgprot is the same: |
|
* Convert protection attributes to 4k-format, as cpa->mask* are set |
|
* up accordingly. |
|
*/ |
|
|
|
/* Clear PSE (aka _PAGE_PAT) and move PAT bit to correct position */ |
|
req_prot = pgprot_large_2_4k(old_prot); |
|
|
|
pgprot_val(req_prot) &= ~pgprot_val(cpa->mask_clr); |
|
pgprot_val(req_prot) |= pgprot_val(cpa->mask_set); |
|
|
|
/* |
|
* req_prot is in format of 4k pages. It must be converted to large |
|
* page format: the caching mode includes the PAT bit located at |
|
* different bit positions in the two formats. |
|
*/ |
|
req_prot = pgprot_4k_2_large(req_prot); |
|
req_prot = pgprot_clear_protnone_bits(req_prot); |
|
if (pgprot_val(req_prot) & _PAGE_PRESENT) |
|
pgprot_val(req_prot) |= _PAGE_PSE; |
|
|
|
/* |
|
* old_pfn points to the large page base pfn. So we need to add the |
|
* offset of the virtual address: |
|
*/ |
|
pfn = old_pfn + ((address & (psize - 1)) >> PAGE_SHIFT); |
|
cpa->pfn = pfn; |
|
|
|
/* |
|
* Calculate the large page base address and the number of 4K pages |
|
* in the large page |
|
*/ |
|
lpaddr = address & pmask; |
|
numpages = psize >> PAGE_SHIFT; |
|
|
|
/* |
|
* Sanity check that the existing mapping is correct versus the static |
|
* protections. static_protections() guards against !PRESENT, so no |
|
* extra conditional required here. |
|
*/ |
|
chk_prot = static_protections(old_prot, lpaddr, old_pfn, numpages, |
|
psize, CPA_CONFLICT); |
|
|
|
if (WARN_ON_ONCE(pgprot_val(chk_prot) != pgprot_val(old_prot))) { |
|
/* |
|
* Split the large page and tell the split code to |
|
* enforce static protections. |
|
*/ |
|
cpa->force_static_prot = 1; |
|
return 1; |
|
} |
|
|
|
/* |
|
* Optimization: If the requested pgprot is the same as the current |
|
* pgprot, then the large page can be preserved and no updates are |
|
* required independent of alignment and length of the requested |
|
* range. The above already established that the current pgprot is |
|
* correct, which in consequence makes the requested pgprot correct |
|
* as well if it is the same. The static protection scan below will |
|
* not come to a different conclusion. |
|
*/ |
|
if (pgprot_val(req_prot) == pgprot_val(old_prot)) { |
|
cpa_inc_lp_sameprot(level); |
|
return 0; |
|
} |
|
|
|
/* |
|
* If the requested range does not cover the full page, split it up |
|
*/ |
|
if (address != lpaddr || cpa->numpages != numpages) |
|
return 1; |
|
|
|
/* |
|
* Check whether the requested pgprot is conflicting with a static |
|
* protection requirement in the large page. |
|
*/ |
|
new_prot = static_protections(req_prot, lpaddr, old_pfn, numpages, |
|
psize, CPA_DETECT); |
|
|
|
/* |
|
* If there is a conflict, split the large page. |
|
* |
|
* There used to be a 4k wise evaluation trying really hard to |
|
* preserve the large pages, but experimentation has shown, that this |
|
* does not help at all. There might be corner cases which would |
|
* preserve one large page occasionally, but it's really not worth the |
|
* extra code and cycles for the common case. |
|
*/ |
|
if (pgprot_val(req_prot) != pgprot_val(new_prot)) |
|
return 1; |
|
|
|
/* All checks passed. Update the large page mapping. */ |
|
new_pte = pfn_pte(old_pfn, new_prot); |
|
__set_pmd_pte(kpte, address, new_pte); |
|
cpa->flags |= CPA_FLUSHTLB; |
|
cpa_inc_lp_preserved(level); |
|
return 0; |
|
} |
|
|
|
static int should_split_large_page(pte_t *kpte, unsigned long address, |
|
struct cpa_data *cpa) |
|
{ |
|
int do_split; |
|
|
|
if (cpa->force_split) |
|
return 1; |
|
|
|
spin_lock(&pgd_lock); |
|
do_split = __should_split_large_page(kpte, address, cpa); |
|
spin_unlock(&pgd_lock); |
|
|
|
return do_split; |
|
} |
|
|
|
static void split_set_pte(struct cpa_data *cpa, pte_t *pte, unsigned long pfn, |
|
pgprot_t ref_prot, unsigned long address, |
|
unsigned long size) |
|
{ |
|
unsigned int npg = PFN_DOWN(size); |
|
pgprot_t prot; |
|
|
|
/* |
|
* If should_split_large_page() discovered an inconsistent mapping, |
|
* remove the invalid protection in the split mapping. |
|
*/ |
|
if (!cpa->force_static_prot) |
|
goto set; |
|
|
|
/* Hand in lpsize = 0 to enforce the protection mechanism */ |
|
prot = static_protections(ref_prot, address, pfn, npg, 0, CPA_PROTECT); |
|
|
|
if (pgprot_val(prot) == pgprot_val(ref_prot)) |
|
goto set; |
|
|
|
/* |
|
* If this is splitting a PMD, fix it up. PUD splits cannot be |
|
* fixed trivially as that would require to rescan the newly |
|
* installed PMD mappings after returning from split_large_page() |
|
* so an eventual further split can allocate the necessary PTE |
|
* pages. Warn for now and revisit it in case this actually |
|
* happens. |
|
*/ |
|
if (size == PAGE_SIZE) |
|
ref_prot = prot; |
|
else |
|
pr_warn_once("CPA: Cannot fixup static protections for PUD split\n"); |
|
set: |
|
set_pte(pte, pfn_pte(pfn, ref_prot)); |
|
} |
|
|
|
static int |
|
__split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address, |
|
struct page *base) |
|
{ |
|
unsigned long lpaddr, lpinc, ref_pfn, pfn, pfninc = 1; |
|
pte_t *pbase = (pte_t *)page_address(base); |
|
unsigned int i, level; |
|
pgprot_t ref_prot; |
|
pte_t *tmp; |
|
|
|
spin_lock(&pgd_lock); |
|
/* |
|
* Check for races, another CPU might have split this page |
|
* up for us already: |
|
*/ |
|
tmp = _lookup_address_cpa(cpa, address, &level); |
|
if (tmp != kpte) { |
|
spin_unlock(&pgd_lock); |
|
return 1; |
|
} |
|
|
|
paravirt_alloc_pte(&init_mm, page_to_pfn(base)); |
|
|
|
switch (level) { |
|
case PG_LEVEL_2M: |
|
ref_prot = pmd_pgprot(*(pmd_t *)kpte); |
|
/* |
|
* Clear PSE (aka _PAGE_PAT) and move |
|
* PAT bit to correct position. |
|
*/ |
|
ref_prot = pgprot_large_2_4k(ref_prot); |
|
ref_pfn = pmd_pfn(*(pmd_t *)kpte); |
|
lpaddr = address & PMD_MASK; |
|
lpinc = PAGE_SIZE; |
|
break; |
|
|
|
case PG_LEVEL_1G: |
|
ref_prot = pud_pgprot(*(pud_t *)kpte); |
|
ref_pfn = pud_pfn(*(pud_t *)kpte); |
|
pfninc = PMD_PAGE_SIZE >> PAGE_SHIFT; |
|
lpaddr = address & PUD_MASK; |
|
lpinc = PMD_SIZE; |
|
/* |
|
* Clear the PSE flags if the PRESENT flag is not set |
|
* otherwise pmd_present/pmd_huge will return true |
|
* even on a non present pmd. |
|
*/ |
|
if (!(pgprot_val(ref_prot) & _PAGE_PRESENT)) |
|
pgprot_val(ref_prot) &= ~_PAGE_PSE; |
|
break; |
|
|
|
default: |
|
spin_unlock(&pgd_lock); |
|
return 1; |
|
} |
|
|
|
ref_prot = pgprot_clear_protnone_bits(ref_prot); |
|
|
|
/* |
|
* Get the target pfn from the original entry: |
|
*/ |
|
pfn = ref_pfn; |
|
for (i = 0; i < PTRS_PER_PTE; i++, pfn += pfninc, lpaddr += lpinc) |
|
split_set_pte(cpa, pbase + i, pfn, ref_prot, lpaddr, lpinc); |
|
|
|
if (virt_addr_valid(address)) { |
|
unsigned long pfn = PFN_DOWN(__pa(address)); |
|
|
|
if (pfn_range_is_mapped(pfn, pfn + 1)) |
|
split_page_count(level); |
|
} |
|
|
|
/* |
|
* Install the new, split up pagetable. |
|
* |
|
* We use the standard kernel pagetable protections for the new |
|
* pagetable protections, the actual ptes set above control the |
|
* primary protection behavior: |
|
*/ |
|
__set_pmd_pte(kpte, address, mk_pte(base, __pgprot(_KERNPG_TABLE))); |
|
|
|
/* |
|
* Do a global flush tlb after splitting the large page |
|
* and before we do the actual change page attribute in the PTE. |
|
* |
|
* Without this, we violate the TLB application note, that says: |
|
* "The TLBs may contain both ordinary and large-page |
|
* translations for a 4-KByte range of linear addresses. This |
|
* may occur if software modifies the paging structures so that |
|
* the page size used for the address range changes. If the two |
|
* translations differ with respect to page frame or attributes |
|
* (e.g., permissions), processor behavior is undefined and may |
|
* be implementation-specific." |
|
* |
|
* We do this global tlb flush inside the cpa_lock, so that we |
|
* don't allow any other cpu, with stale tlb entries change the |
|
* page attribute in parallel, that also falls into the |
|
* just split large page entry. |
|
*/ |
|
flush_tlb_all(); |
|
spin_unlock(&pgd_lock); |
|
|
|
return 0; |
|
} |
|
|
|
static int split_large_page(struct cpa_data *cpa, pte_t *kpte, |
|
unsigned long address) |
|
{ |
|
struct page *base; |
|
|
|
if (!debug_pagealloc_enabled()) |
|
spin_unlock(&cpa_lock); |
|
base = alloc_pages(GFP_KERNEL, 0); |
|
if (!debug_pagealloc_enabled()) |
|
spin_lock(&cpa_lock); |
|
if (!base) |
|
return -ENOMEM; |
|
|
|
if (__split_large_page(cpa, kpte, address, base)) |
|
__free_page(base); |
|
|
|
return 0; |
|
} |
|
|
|
static bool try_to_free_pte_page(pte_t *pte) |
|
{ |
|
int i; |
|
|
|
for (i = 0; i < PTRS_PER_PTE; i++) |
|
if (!pte_none(pte[i])) |
|
return false; |
|
|
|
free_page((unsigned long)pte); |
|
return true; |
|
} |
|
|
|
static bool try_to_free_pmd_page(pmd_t *pmd) |
|
{ |
|
int i; |
|
|
|
for (i = 0; i < PTRS_PER_PMD; i++) |
|
if (!pmd_none(pmd[i])) |
|
return false; |
|
|
|
free_page((unsigned long)pmd); |
|
return true; |
|
} |
|
|
|
static bool unmap_pte_range(pmd_t *pmd, unsigned long start, unsigned long end) |
|
{ |
|
pte_t *pte = pte_offset_kernel(pmd, start); |
|
|
|
while (start < end) { |
|
set_pte(pte, __pte(0)); |
|
|
|
start += PAGE_SIZE; |
|
pte++; |
|
} |
|
|
|
if (try_to_free_pte_page((pte_t *)pmd_page_vaddr(*pmd))) { |
|
pmd_clear(pmd); |
|
return true; |
|
} |
|
return false; |
|
} |
|
|
|
static void __unmap_pmd_range(pud_t *pud, pmd_t *pmd, |
|
unsigned long start, unsigned long end) |
|
{ |
|
if (unmap_pte_range(pmd, start, end)) |
|
if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud))) |
|
pud_clear(pud); |
|
} |
|
|
|
static void unmap_pmd_range(pud_t *pud, unsigned long start, unsigned long end) |
|
{ |
|
pmd_t *pmd = pmd_offset(pud, start); |
|
|
|
/* |
|
* Not on a 2MB page boundary? |
|
*/ |
|
if (start & (PMD_SIZE - 1)) { |
|
unsigned long next_page = (start + PMD_SIZE) & PMD_MASK; |
|
unsigned long pre_end = min_t(unsigned long, end, next_page); |
|
|
|
__unmap_pmd_range(pud, pmd, start, pre_end); |
|
|
|
start = pre_end; |
|
pmd++; |
|
} |
|
|
|
/* |
|
* Try to unmap in 2M chunks. |
|
*/ |
|
while (end - start >= PMD_SIZE) { |
|
if (pmd_large(*pmd)) |
|
pmd_clear(pmd); |
|
else |
|
__unmap_pmd_range(pud, pmd, start, start + PMD_SIZE); |
|
|
|
start += PMD_SIZE; |
|
pmd++; |
|
} |
|
|
|
/* |
|
* 4K leftovers? |
|
*/ |
|
if (start < end) |
|
return __unmap_pmd_range(pud, pmd, start, end); |
|
|
|
/* |
|
* Try again to free the PMD page if haven't succeeded above. |
|
*/ |
|
if (!pud_none(*pud)) |
|
if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud))) |
|
pud_clear(pud); |
|
} |
|
|
|
static void unmap_pud_range(p4d_t *p4d, unsigned long start, unsigned long end) |
|
{ |
|
pud_t *pud = pud_offset(p4d, start); |
|
|
|
/* |
|
* Not on a GB page boundary? |
|
*/ |
|
if (start & (PUD_SIZE - 1)) { |
|
unsigned long next_page = (start + PUD_SIZE) & PUD_MASK; |
|
unsigned long pre_end = min_t(unsigned long, end, next_page); |
|
|
|
unmap_pmd_range(pud, start, pre_end); |
|
|
|
start = pre_end; |
|
pud++; |
|
} |
|
|
|
/* |
|
* Try to unmap in 1G chunks? |
|
*/ |
|
while (end - start >= PUD_SIZE) { |
|
|
|
if (pud_large(*pud)) |
|
pud_clear(pud); |
|
else |
|
unmap_pmd_range(pud, start, start + PUD_SIZE); |
|
|
|
start += PUD_SIZE; |
|
pud++; |
|
} |
|
|
|
/* |
|
* 2M leftovers? |
|
*/ |
|
if (start < end) |
|
unmap_pmd_range(pud, start, end); |
|
|
|
/* |
|
* No need to try to free the PUD page because we'll free it in |
|
* populate_pgd's error path |
|
*/ |
|
} |
|
|
|
static int alloc_pte_page(pmd_t *pmd) |
|
{ |
|
pte_t *pte = (pte_t *)get_zeroed_page(GFP_KERNEL); |
|
if (!pte) |
|
return -1; |
|
|
|
set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE)); |
|
return 0; |
|
} |
|
|
|
static int alloc_pmd_page(pud_t *pud) |
|
{ |
|
pmd_t *pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL); |
|
if (!pmd) |
|
return -1; |
|
|
|
set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE)); |
|
return 0; |
|
} |
|
|
|
static void populate_pte(struct cpa_data *cpa, |
|
unsigned long start, unsigned long end, |
|
unsigned num_pages, pmd_t *pmd, pgprot_t pgprot) |
|
{ |
|
pte_t *pte; |
|
|
|
pte = pte_offset_kernel(pmd, start); |
|
|
|
pgprot = pgprot_clear_protnone_bits(pgprot); |
|
|
|
while (num_pages-- && start < end) { |
|
set_pte(pte, pfn_pte(cpa->pfn, pgprot)); |
|
|
|
start += PAGE_SIZE; |
|
cpa->pfn++; |
|
pte++; |
|
} |
|
} |
|
|
|
static long populate_pmd(struct cpa_data *cpa, |
|
unsigned long start, unsigned long end, |
|
unsigned num_pages, pud_t *pud, pgprot_t pgprot) |
|
{ |
|
long cur_pages = 0; |
|
pmd_t *pmd; |
|
pgprot_t pmd_pgprot; |
|
|
|
/* |
|
* Not on a 2M boundary? |
|
*/ |
|
if (start & (PMD_SIZE - 1)) { |
|
unsigned long pre_end = start + (num_pages << PAGE_SHIFT); |
|
unsigned long next_page = (start + PMD_SIZE) & PMD_MASK; |
|
|
|
pre_end = min_t(unsigned long, pre_end, next_page); |
|
cur_pages = (pre_end - start) >> PAGE_SHIFT; |
|
cur_pages = min_t(unsigned int, num_pages, cur_pages); |
|
|
|
/* |
|
* Need a PTE page? |
|
*/ |
|
pmd = pmd_offset(pud, start); |
|
if (pmd_none(*pmd)) |
|
if (alloc_pte_page(pmd)) |
|
return -1; |
|
|
|
populate_pte(cpa, start, pre_end, cur_pages, pmd, pgprot); |
|
|
|
start = pre_end; |
|
} |
|
|
|
/* |
|
* We mapped them all? |
|
*/ |
|
if (num_pages == cur_pages) |
|
return cur_pages; |
|
|
|
pmd_pgprot = pgprot_4k_2_large(pgprot); |
|
|
|
while (end - start >= PMD_SIZE) { |
|
|
|
/* |
|
* We cannot use a 1G page so allocate a PMD page if needed. |
|
*/ |
|
if (pud_none(*pud)) |
|
if (alloc_pmd_page(pud)) |
|
return -1; |
|
|
|
pmd = pmd_offset(pud, start); |
|
|
|
set_pmd(pmd, pmd_mkhuge(pfn_pmd(cpa->pfn, |
|
canon_pgprot(pmd_pgprot)))); |
|
|
|
start += PMD_SIZE; |
|
cpa->pfn += PMD_SIZE >> PAGE_SHIFT; |
|
cur_pages += PMD_SIZE >> PAGE_SHIFT; |
|
} |
|
|
|
/* |
|
* Map trailing 4K pages. |
|
*/ |
|
if (start < end) { |
|
pmd = pmd_offset(pud, start); |
|
if (pmd_none(*pmd)) |
|
if (alloc_pte_page(pmd)) |
|
return -1; |
|
|
|
populate_pte(cpa, start, end, num_pages - cur_pages, |
|
pmd, pgprot); |
|
} |
|
return num_pages; |
|
} |
|
|
|
static int populate_pud(struct cpa_data *cpa, unsigned long start, p4d_t *p4d, |
|
pgprot_t pgprot) |
|
{ |
|
pud_t *pud; |
|
unsigned long end; |
|
long cur_pages = 0; |
|
pgprot_t pud_pgprot; |
|
|
|
end = start + (cpa->numpages << PAGE_SHIFT); |
|
|
|
/* |
|
* Not on a Gb page boundary? => map everything up to it with |
|
* smaller pages. |
|
*/ |
|
if (start & (PUD_SIZE - 1)) { |
|
unsigned long pre_end; |
|
unsigned long next_page = (start + PUD_SIZE) & PUD_MASK; |
|
|
|
pre_end = min_t(unsigned long, end, next_page); |
|
cur_pages = (pre_end - start) >> PAGE_SHIFT; |
|
cur_pages = min_t(int, (int)cpa->numpages, cur_pages); |
|
|
|
pud = pud_offset(p4d, start); |
|
|
|
/* |
|
* Need a PMD page? |
|
*/ |
|
if (pud_none(*pud)) |
|
if (alloc_pmd_page(pud)) |
|
return -1; |
|
|
|
cur_pages = populate_pmd(cpa, start, pre_end, cur_pages, |
|
pud, pgprot); |
|
if (cur_pages < 0) |
|
return cur_pages; |
|
|
|
start = pre_end; |
|
} |
|
|
|
/* We mapped them all? */ |
|
if (cpa->numpages == cur_pages) |
|
return cur_pages; |
|
|
|
pud = pud_offset(p4d, start); |
|
pud_pgprot = pgprot_4k_2_large(pgprot); |
|
|
|
/* |
|
* Map everything starting from the Gb boundary, possibly with 1G pages |
|
*/ |
|
while (boot_cpu_has(X86_FEATURE_GBPAGES) && end - start >= PUD_SIZE) { |
|
set_pud(pud, pud_mkhuge(pfn_pud(cpa->pfn, |
|
canon_pgprot(pud_pgprot)))); |
|
|
|
start += PUD_SIZE; |
|
cpa->pfn += PUD_SIZE >> PAGE_SHIFT; |
|
cur_pages += PUD_SIZE >> PAGE_SHIFT; |
|
pud++; |
|
} |
|
|
|
/* Map trailing leftover */ |
|
if (start < end) { |
|
long tmp; |
|
|
|
pud = pud_offset(p4d, start); |
|
if (pud_none(*pud)) |
|
if (alloc_pmd_page(pud)) |
|
return -1; |
|
|
|
tmp = populate_pmd(cpa, start, end, cpa->numpages - cur_pages, |
|
pud, pgprot); |
|
if (tmp < 0) |
|
return cur_pages; |
|
|
|
cur_pages += tmp; |
|
} |
|
return cur_pages; |
|
} |
|
|
|
/* |
|
* Restrictions for kernel page table do not necessarily apply when mapping in |
|
* an alternate PGD. |
|
*/ |
|
static int populate_pgd(struct cpa_data *cpa, unsigned long addr) |
|
{ |
|
pgprot_t pgprot = __pgprot(_KERNPG_TABLE); |
|
pud_t *pud = NULL; /* shut up gcc */ |
|
p4d_t *p4d; |
|
pgd_t *pgd_entry; |
|
long ret; |
|
|
|
pgd_entry = cpa->pgd + pgd_index(addr); |
|
|
|
if (pgd_none(*pgd_entry)) { |
|
p4d = (p4d_t *)get_zeroed_page(GFP_KERNEL); |
|
if (!p4d) |
|
return -1; |
|
|
|
set_pgd(pgd_entry, __pgd(__pa(p4d) | _KERNPG_TABLE)); |
|
} |
|
|
|
/* |
|
* Allocate a PUD page and hand it down for mapping. |
|
*/ |
|
p4d = p4d_offset(pgd_entry, addr); |
|
if (p4d_none(*p4d)) { |
|
pud = (pud_t *)get_zeroed_page(GFP_KERNEL); |
|
if (!pud) |
|
return -1; |
|
|
|
set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE)); |
|
} |
|
|
|
pgprot_val(pgprot) &= ~pgprot_val(cpa->mask_clr); |
|
pgprot_val(pgprot) |= pgprot_val(cpa->mask_set); |
|
|
|
ret = populate_pud(cpa, addr, p4d, pgprot); |
|
if (ret < 0) { |
|
/* |
|
* Leave the PUD page in place in case some other CPU or thread |
|
* already found it, but remove any useless entries we just |
|
* added to it. |
|
*/ |
|
unmap_pud_range(p4d, addr, |
|
addr + (cpa->numpages << PAGE_SHIFT)); |
|
return ret; |
|
} |
|
|
|
cpa->numpages = ret; |
|
return 0; |
|
} |
|
|
|
static int __cpa_process_fault(struct cpa_data *cpa, unsigned long vaddr, |
|
int primary) |
|
{ |
|
if (cpa->pgd) { |
|
/* |
|
* Right now, we only execute this code path when mapping |
|
* the EFI virtual memory map regions, no other users |
|
* provide a ->pgd value. This may change in the future. |
|
*/ |
|
return populate_pgd(cpa, vaddr); |
|
} |
|
|
|
/* |
|
* Ignore all non primary paths. |
|
*/ |
|
if (!primary) { |
|
cpa->numpages = 1; |
|
return 0; |
|
} |
|
|
|
/* |
|
* Ignore the NULL PTE for kernel identity mapping, as it is expected |
|
* to have holes. |
|
* Also set numpages to '1' indicating that we processed cpa req for |
|
* one virtual address page and its pfn. TBD: numpages can be set based |
|
* on the initial value and the level returned by lookup_address(). |
|
*/ |
|
if (within(vaddr, PAGE_OFFSET, |
|
PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT))) { |
|
cpa->numpages = 1; |
|
cpa->pfn = __pa(vaddr) >> PAGE_SHIFT; |
|
return 0; |
|
|
|
} else if (__cpa_pfn_in_highmap(cpa->pfn)) { |
|
/* Faults in the highmap are OK, so do not warn: */ |
|
return -EFAULT; |
|
} else { |
|
WARN(1, KERN_WARNING "CPA: called for zero pte. " |
|
"vaddr = %lx cpa->vaddr = %lx\n", vaddr, |
|
*cpa->vaddr); |
|
|
|
return -EFAULT; |
|
} |
|
} |
|
|
|
static int __change_page_attr(struct cpa_data *cpa, int primary) |
|
{ |
|
unsigned long address; |
|
int do_split, err; |
|
unsigned int level; |
|
pte_t *kpte, old_pte; |
|
|
|
address = __cpa_addr(cpa, cpa->curpage); |
|
repeat: |
|
kpte = _lookup_address_cpa(cpa, address, &level); |
|
if (!kpte) |
|
return __cpa_process_fault(cpa, address, primary); |
|
|
|
old_pte = *kpte; |
|
if (pte_none(old_pte)) |
|
return __cpa_process_fault(cpa, address, primary); |
|
|
|
if (level == PG_LEVEL_4K) { |
|
pte_t new_pte; |
|
pgprot_t new_prot = pte_pgprot(old_pte); |
|
unsigned long pfn = pte_pfn(old_pte); |
|
|
|
pgprot_val(new_prot) &= ~pgprot_val(cpa->mask_clr); |
|
pgprot_val(new_prot) |= pgprot_val(cpa->mask_set); |
|
|
|
cpa_inc_4k_install(); |
|
/* Hand in lpsize = 0 to enforce the protection mechanism */ |
|
new_prot = static_protections(new_prot, address, pfn, 1, 0, |
|
CPA_PROTECT); |
|
|
|
new_prot = pgprot_clear_protnone_bits(new_prot); |
|
|
|
/* |
|
* We need to keep the pfn from the existing PTE, |
|
* after all we're only going to change it's attributes |
|
* not the memory it points to |
|
*/ |
|
new_pte = pfn_pte(pfn, new_prot); |
|
cpa->pfn = pfn; |
|
/* |
|
* Do we really change anything ? |
|
*/ |
|
if (pte_val(old_pte) != pte_val(new_pte)) { |
|
set_pte_atomic(kpte, new_pte); |
|
cpa->flags |= CPA_FLUSHTLB; |
|
} |
|
cpa->numpages = 1; |
|
return 0; |
|
} |
|
|
|
/* |
|
* Check, whether we can keep the large page intact |
|
* and just change the pte: |
|
*/ |
|
do_split = should_split_large_page(kpte, address, cpa); |
|
/* |
|
* When the range fits into the existing large page, |
|
* return. cp->numpages and cpa->tlbflush have been updated in |
|
* try_large_page: |
|
*/ |
|
if (do_split <= 0) |
|
return do_split; |
|
|
|
/* |
|
* We have to split the large page: |
|
*/ |
|
err = split_large_page(cpa, kpte, address); |
|
if (!err) |
|
goto repeat; |
|
|
|
return err; |
|
} |
|
|
|
static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias); |
|
|
|
static int cpa_process_alias(struct cpa_data *cpa) |
|
{ |
|
struct cpa_data alias_cpa; |
|
unsigned long laddr = (unsigned long)__va(cpa->pfn << PAGE_SHIFT); |
|
unsigned long vaddr; |
|
int ret; |
|
|
|
if (!pfn_range_is_mapped(cpa->pfn, cpa->pfn + 1)) |
|
return 0; |
|
|
|
/* |
|
* No need to redo, when the primary call touched the direct |
|
* mapping already: |
|
*/ |
|
vaddr = __cpa_addr(cpa, cpa->curpage); |
|
if (!(within(vaddr, PAGE_OFFSET, |
|
PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT)))) { |
|
|
|
alias_cpa = *cpa; |
|
alias_cpa.vaddr = &laddr; |
|
alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY); |
|
alias_cpa.curpage = 0; |
|
|
|
cpa->force_flush_all = 1; |
|
|
|
ret = __change_page_attr_set_clr(&alias_cpa, 0); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
#ifdef CONFIG_X86_64 |
|
/* |
|
* If the primary call didn't touch the high mapping already |
|
* and the physical address is inside the kernel map, we need |
|
* to touch the high mapped kernel as well: |
|
*/ |
|
if (!within(vaddr, (unsigned long)_text, _brk_end) && |
|
__cpa_pfn_in_highmap(cpa->pfn)) { |
|
unsigned long temp_cpa_vaddr = (cpa->pfn << PAGE_SHIFT) + |
|
__START_KERNEL_map - phys_base; |
|
alias_cpa = *cpa; |
|
alias_cpa.vaddr = &temp_cpa_vaddr; |
|
alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY); |
|
alias_cpa.curpage = 0; |
|
|
|
cpa->force_flush_all = 1; |
|
/* |
|
* The high mapping range is imprecise, so ignore the |
|
* return value. |
|
*/ |
|
__change_page_attr_set_clr(&alias_cpa, 0); |
|
} |
|
#endif |
|
|
|
return 0; |
|
} |
|
|
|
static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias) |
|
{ |
|
unsigned long numpages = cpa->numpages; |
|
unsigned long rempages = numpages; |
|
int ret = 0; |
|
|
|
while (rempages) { |
|
/* |
|
* Store the remaining nr of pages for the large page |
|
* preservation check. |
|
*/ |
|
cpa->numpages = rempages; |
|
/* for array changes, we can't use large page */ |
|
if (cpa->flags & (CPA_ARRAY | CPA_PAGES_ARRAY)) |
|
cpa->numpages = 1; |
|
|
|
if (!debug_pagealloc_enabled()) |
|
spin_lock(&cpa_lock); |
|
ret = __change_page_attr(cpa, checkalias); |
|
if (!debug_pagealloc_enabled()) |
|
spin_unlock(&cpa_lock); |
|
if (ret) |
|
goto out; |
|
|
|
if (checkalias) { |
|
ret = cpa_process_alias(cpa); |
|
if (ret) |
|
goto out; |
|
} |
|
|
|
/* |
|
* Adjust the number of pages with the result of the |
|
* CPA operation. Either a large page has been |
|
* preserved or a single page update happened. |
|
*/ |
|
BUG_ON(cpa->numpages > rempages || !cpa->numpages); |
|
rempages -= cpa->numpages; |
|
cpa->curpage += cpa->numpages; |
|
} |
|
|
|
out: |
|
/* Restore the original numpages */ |
|
cpa->numpages = numpages; |
|
return ret; |
|
} |
|
|
|
static int change_page_attr_set_clr(unsigned long *addr, int numpages, |
|
pgprot_t mask_set, pgprot_t mask_clr, |
|
int force_split, int in_flag, |
|
struct page **pages) |
|
{ |
|
struct cpa_data cpa; |
|
int ret, cache, checkalias; |
|
|
|
memset(&cpa, 0, sizeof(cpa)); |
|
|
|
/* |
|
* Check, if we are requested to set a not supported |
|
* feature. Clearing non-supported features is OK. |
|
*/ |
|
mask_set = canon_pgprot(mask_set); |
|
|
|
if (!pgprot_val(mask_set) && !pgprot_val(mask_clr) && !force_split) |
|
return 0; |
|
|
|
/* Ensure we are PAGE_SIZE aligned */ |
|
if (in_flag & CPA_ARRAY) { |
|
int i; |
|
for (i = 0; i < numpages; i++) { |
|
if (addr[i] & ~PAGE_MASK) { |
|
addr[i] &= PAGE_MASK; |
|
WARN_ON_ONCE(1); |
|
} |
|
} |
|
} else if (!(in_flag & CPA_PAGES_ARRAY)) { |
|
/* |
|
* in_flag of CPA_PAGES_ARRAY implies it is aligned. |
|
* No need to check in that case |
|
*/ |
|
if (*addr & ~PAGE_MASK) { |
|
*addr &= PAGE_MASK; |
|
/* |
|
* People should not be passing in unaligned addresses: |
|
*/ |
|
WARN_ON_ONCE(1); |
|
} |
|
} |
|
|
|
/* Must avoid aliasing mappings in the highmem code */ |
|
kmap_flush_unused(); |
|
|
|
vm_unmap_aliases(); |
|
|
|
cpa.vaddr = addr; |
|
cpa.pages = pages; |
|
cpa.numpages = numpages; |
|
cpa.mask_set = mask_set; |
|
cpa.mask_clr = mask_clr; |
|
cpa.flags = 0; |
|
cpa.curpage = 0; |
|
cpa.force_split = force_split; |
|
|
|
if (in_flag & (CPA_ARRAY | CPA_PAGES_ARRAY)) |
|
cpa.flags |= in_flag; |
|
|
|
/* No alias checking for _NX bit modifications */ |
|
checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX; |
|
/* Has caller explicitly disabled alias checking? */ |
|
if (in_flag & CPA_NO_CHECK_ALIAS) |
|
checkalias = 0; |
|
|
|
ret = __change_page_attr_set_clr(&cpa, checkalias); |
|
|
|
/* |
|
* Check whether we really changed something: |
|
*/ |
|
if (!(cpa.flags & CPA_FLUSHTLB)) |
|
goto out; |
|
|
|
/* |
|
* No need to flush, when we did not set any of the caching |
|
* attributes: |
|
*/ |
|
cache = !!pgprot2cachemode(mask_set); |
|
|
|
/* |
|
* On error; flush everything to be sure. |
|
*/ |
|
if (ret) { |
|
cpa_flush_all(cache); |
|
goto out; |
|
} |
|
|
|
cpa_flush(&cpa, cache); |
|
out: |
|
return ret; |
|
} |
|
|
|
static inline int change_page_attr_set(unsigned long *addr, int numpages, |
|
pgprot_t mask, int array) |
|
{ |
|
return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0), 0, |
|
(array ? CPA_ARRAY : 0), NULL); |
|
} |
|
|
|
static inline int change_page_attr_clear(unsigned long *addr, int numpages, |
|
pgprot_t mask, int array) |
|
{ |
|
return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask, 0, |
|
(array ? CPA_ARRAY : 0), NULL); |
|
} |
|
|
|
static inline int cpa_set_pages_array(struct page **pages, int numpages, |
|
pgprot_t mask) |
|
{ |
|
return change_page_attr_set_clr(NULL, numpages, mask, __pgprot(0), 0, |
|
CPA_PAGES_ARRAY, pages); |
|
} |
|
|
|
static inline int cpa_clear_pages_array(struct page **pages, int numpages, |
|
pgprot_t mask) |
|
{ |
|
return change_page_attr_set_clr(NULL, numpages, __pgprot(0), mask, 0, |
|
CPA_PAGES_ARRAY, pages); |
|
} |
|
|
|
/* |
|
* _set_memory_prot is an internal helper for callers that have been passed |
|
* a pgprot_t value from upper layers and a reservation has already been taken. |
|
* If you want to set the pgprot to a specific page protocol, use the |
|
* set_memory_xx() functions. |
|
*/ |
|
int __set_memory_prot(unsigned long addr, int numpages, pgprot_t prot) |
|
{ |
|
return change_page_attr_set_clr(&addr, numpages, prot, |
|
__pgprot(~pgprot_val(prot)), 0, 0, |
|
NULL); |
|
} |
|
|
|
int _set_memory_uc(unsigned long addr, int numpages) |
|
{ |
|
/* |
|
* for now UC MINUS. see comments in ioremap() |
|
* If you really need strong UC use ioremap_uc(), but note |
|
* that you cannot override IO areas with set_memory_*() as |
|
* these helpers cannot work with IO memory. |
|
*/ |
|
return change_page_attr_set(&addr, numpages, |
|
cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS), |
|
0); |
|
} |
|
|
|
int set_memory_uc(unsigned long addr, int numpages) |
|
{ |
|
int ret; |
|
|
|
/* |
|
* for now UC MINUS. see comments in ioremap() |
|
*/ |
|
ret = memtype_reserve(__pa(addr), __pa(addr) + numpages * PAGE_SIZE, |
|
_PAGE_CACHE_MODE_UC_MINUS, NULL); |
|
if (ret) |
|
goto out_err; |
|
|
|
ret = _set_memory_uc(addr, numpages); |
|
if (ret) |
|
goto out_free; |
|
|
|
return 0; |
|
|
|
out_free: |
|
memtype_free(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); |
|
out_err: |
|
return ret; |
|
} |
|
EXPORT_SYMBOL(set_memory_uc); |
|
|
|
int _set_memory_wc(unsigned long addr, int numpages) |
|
{ |
|
int ret; |
|
|
|
ret = change_page_attr_set(&addr, numpages, |
|
cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS), |
|
0); |
|
if (!ret) { |
|
ret = change_page_attr_set_clr(&addr, numpages, |
|
cachemode2pgprot(_PAGE_CACHE_MODE_WC), |
|
__pgprot(_PAGE_CACHE_MASK), |
|
0, 0, NULL); |
|
} |
|
return ret; |
|
} |
|
|
|
int set_memory_wc(unsigned long addr, int numpages) |
|
{ |
|
int ret; |
|
|
|
ret = memtype_reserve(__pa(addr), __pa(addr) + numpages * PAGE_SIZE, |
|
_PAGE_CACHE_MODE_WC, NULL); |
|
if (ret) |
|
return ret; |
|
|
|
ret = _set_memory_wc(addr, numpages); |
|
if (ret) |
|
memtype_free(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); |
|
|
|
return ret; |
|
} |
|
EXPORT_SYMBOL(set_memory_wc); |
|
|
|
int _set_memory_wt(unsigned long addr, int numpages) |
|
{ |
|
return change_page_attr_set(&addr, numpages, |
|
cachemode2pgprot(_PAGE_CACHE_MODE_WT), 0); |
|
} |
|
|
|
int _set_memory_wb(unsigned long addr, int numpages) |
|
{ |
|
/* WB cache mode is hard wired to all cache attribute bits being 0 */ |
|
return change_page_attr_clear(&addr, numpages, |
|
__pgprot(_PAGE_CACHE_MASK), 0); |
|
} |
|
|
|
int set_memory_wb(unsigned long addr, int numpages) |
|
{ |
|
int ret; |
|
|
|
ret = _set_memory_wb(addr, numpages); |
|
if (ret) |
|
return ret; |
|
|
|
memtype_free(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); |
|
return 0; |
|
} |
|
EXPORT_SYMBOL(set_memory_wb); |
|
|
|
int set_memory_x(unsigned long addr, int numpages) |
|
{ |
|
if (!(__supported_pte_mask & _PAGE_NX)) |
|
return 0; |
|
|
|
return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_NX), 0); |
|
} |
|
|
|
int set_memory_nx(unsigned long addr, int numpages) |
|
{ |
|
if (!(__supported_pte_mask & _PAGE_NX)) |
|
return 0; |
|
|
|
return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_NX), 0); |
|
} |
|
|
|
int set_memory_ro(unsigned long addr, int numpages) |
|
{ |
|
return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_RW), 0); |
|
} |
|
|
|
int set_memory_rw(unsigned long addr, int numpages) |
|
{ |
|
return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_RW), 0); |
|
} |
|
|
|
int set_memory_np(unsigned long addr, int numpages) |
|
{ |
|
return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_PRESENT), 0); |
|
} |
|
|
|
int set_memory_np_noalias(unsigned long addr, int numpages) |
|
{ |
|
int cpa_flags = CPA_NO_CHECK_ALIAS; |
|
|
|
return change_page_attr_set_clr(&addr, numpages, __pgprot(0), |
|
__pgprot(_PAGE_PRESENT), 0, |
|
cpa_flags, NULL); |
|
} |
|
|
|
int set_memory_4k(unsigned long addr, int numpages) |
|
{ |
|
return change_page_attr_set_clr(&addr, numpages, __pgprot(0), |
|
__pgprot(0), 1, 0, NULL); |
|
} |
|
|
|
int set_memory_nonglobal(unsigned long addr, int numpages) |
|
{ |
|
return change_page_attr_clear(&addr, numpages, |
|
__pgprot(_PAGE_GLOBAL), 0); |
|
} |
|
|
|
int set_memory_global(unsigned long addr, int numpages) |
|
{ |
|
return change_page_attr_set(&addr, numpages, |
|
__pgprot(_PAGE_GLOBAL), 0); |
|
} |
|
|
|
static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc) |
|
{ |
|
struct cpa_data cpa; |
|
int ret; |
|
|
|
/* Nothing to do if memory encryption is not active */ |
|
if (!mem_encrypt_active()) |
|
return 0; |
|
|
|
/* Should not be working on unaligned addresses */ |
|
if (WARN_ONCE(addr & ~PAGE_MASK, "misaligned address: %#lx\n", addr)) |
|
addr &= PAGE_MASK; |
|
|
|
memset(&cpa, 0, sizeof(cpa)); |
|
cpa.vaddr = &addr; |
|
cpa.numpages = numpages; |
|
cpa.mask_set = enc ? __pgprot(_PAGE_ENC) : __pgprot(0); |
|
cpa.mask_clr = enc ? __pgprot(0) : __pgprot(_PAGE_ENC); |
|
cpa.pgd = init_mm.pgd; |
|
|
|
/* Must avoid aliasing mappings in the highmem code */ |
|
kmap_flush_unused(); |
|
vm_unmap_aliases(); |
|
|
|
/* |
|
* Before changing the encryption attribute, we need to flush caches. |
|
*/ |
|
cpa_flush(&cpa, !this_cpu_has(X86_FEATURE_SME_COHERENT)); |
|
|
|
ret = __change_page_attr_set_clr(&cpa, 1); |
|
|
|
/* |
|
* After changing the encryption attribute, we need to flush TLBs again |
|
* in case any speculative TLB caching occurred (but no need to flush |
|
* caches again). We could just use cpa_flush_all(), but in case TLB |
|
* flushing gets optimized in the cpa_flush() path use the same logic |
|
* as above. |
|
*/ |
|
cpa_flush(&cpa, 0); |
|
|
|
return ret; |
|
} |
|
|
|
int set_memory_encrypted(unsigned long addr, int numpages) |
|
{ |
|
return __set_memory_enc_dec(addr, numpages, true); |
|
} |
|
EXPORT_SYMBOL_GPL(set_memory_encrypted); |
|
|
|
int set_memory_decrypted(unsigned long addr, int numpages) |
|
{ |
|
return __set_memory_enc_dec(addr, numpages, false); |
|
} |
|
EXPORT_SYMBOL_GPL(set_memory_decrypted); |
|
|
|
int set_pages_uc(struct page *page, int numpages) |
|
{ |
|
unsigned long addr = (unsigned long)page_address(page); |
|
|
|
return set_memory_uc(addr, numpages); |
|
} |
|
EXPORT_SYMBOL(set_pages_uc); |
|
|
|
static int _set_pages_array(struct page **pages, int numpages, |
|
enum page_cache_mode new_type) |
|
{ |
|
unsigned long start; |
|
unsigned long end; |
|
enum page_cache_mode set_type; |
|
int i; |
|
int free_idx; |
|
int ret; |
|
|
|
for (i = 0; i < numpages; i++) { |
|
if (PageHighMem(pages[i])) |
|
continue; |
|
start = page_to_pfn(pages[i]) << PAGE_SHIFT; |
|
end = start + PAGE_SIZE; |
|
if (memtype_reserve(start, end, new_type, NULL)) |
|
goto err_out; |
|
} |
|
|
|
/* If WC, set to UC- first and then WC */ |
|
set_type = (new_type == _PAGE_CACHE_MODE_WC) ? |
|
_PAGE_CACHE_MODE_UC_MINUS : new_type; |
|
|
|
ret = cpa_set_pages_array(pages, numpages, |
|
cachemode2pgprot(set_type)); |
|
if (!ret && new_type == _PAGE_CACHE_MODE_WC) |
|
ret = change_page_attr_set_clr(NULL, numpages, |
|
cachemode2pgprot( |
|
_PAGE_CACHE_MODE_WC), |
|
__pgprot(_PAGE_CACHE_MASK), |
|
0, CPA_PAGES_ARRAY, pages); |
|
if (ret) |
|
goto err_out; |
|
return 0; /* Success */ |
|
err_out: |
|
free_idx = i; |
|
for (i = 0; i < free_idx; i++) { |
|
if (PageHighMem(pages[i])) |
|
continue; |
|
start = page_to_pfn(pages[i]) << PAGE_SHIFT; |
|
end = start + PAGE_SIZE; |
|
memtype_free(start, end); |
|
} |
|
return -EINVAL; |
|
} |
|
|
|
int set_pages_array_uc(struct page **pages, int numpages) |
|
{ |
|
return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_UC_MINUS); |
|
} |
|
EXPORT_SYMBOL(set_pages_array_uc); |
|
|
|
int set_pages_array_wc(struct page **pages, int numpages) |
|
{ |
|
return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_WC); |
|
} |
|
EXPORT_SYMBOL(set_pages_array_wc); |
|
|
|
int set_pages_array_wt(struct page **pages, int numpages) |
|
{ |
|
return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_WT); |
|
} |
|
EXPORT_SYMBOL_GPL(set_pages_array_wt); |
|
|
|
int set_pages_wb(struct page *page, int numpages) |
|
{ |
|
unsigned long addr = (unsigned long)page_address(page); |
|
|
|
return set_memory_wb(addr, numpages); |
|
} |
|
EXPORT_SYMBOL(set_pages_wb); |
|
|
|
int set_pages_array_wb(struct page **pages, int numpages) |
|
{ |
|
int retval; |
|
unsigned long start; |
|
unsigned long end; |
|
int i; |
|
|
|
/* WB cache mode is hard wired to all cache attribute bits being 0 */ |
|
retval = cpa_clear_pages_array(pages, numpages, |
|
__pgprot(_PAGE_CACHE_MASK)); |
|
if (retval) |
|
return retval; |
|
|
|
for (i = 0; i < numpages; i++) { |
|
if (PageHighMem(pages[i])) |
|
continue; |
|
start = page_to_pfn(pages[i]) << PAGE_SHIFT; |
|
end = start + PAGE_SIZE; |
|
memtype_free(start, end); |
|
} |
|
|
|
return 0; |
|
} |
|
EXPORT_SYMBOL(set_pages_array_wb); |
|
|
|
int set_pages_ro(struct page *page, int numpages) |
|
{ |
|
unsigned long addr = (unsigned long)page_address(page); |
|
|
|
return set_memory_ro(addr, numpages); |
|
} |
|
|
|
int set_pages_rw(struct page *page, int numpages) |
|
{ |
|
unsigned long addr = (unsigned long)page_address(page); |
|
|
|
return set_memory_rw(addr, numpages); |
|
} |
|
|
|
static int __set_pages_p(struct page *page, int numpages) |
|
{ |
|
unsigned long tempaddr = (unsigned long) page_address(page); |
|
struct cpa_data cpa = { .vaddr = &tempaddr, |
|
.pgd = NULL, |
|
.numpages = numpages, |
|
.mask_set = __pgprot(_PAGE_PRESENT | _PAGE_RW), |
|
.mask_clr = __pgprot(0), |
|
.flags = 0}; |
|
|
|
/* |
|
* No alias checking needed for setting present flag. otherwise, |
|
* we may need to break large pages for 64-bit kernel text |
|
* mappings (this adds to complexity if we want to do this from |
|
* atomic context especially). Let's keep it simple! |
|
*/ |
|
return __change_page_attr_set_clr(&cpa, 0); |
|
} |
|
|
|
static int __set_pages_np(struct page *page, int numpages) |
|
{ |
|
unsigned long tempaddr = (unsigned long) page_address(page); |
|
struct cpa_data cpa = { .vaddr = &tempaddr, |
|
.pgd = NULL, |
|
.numpages = numpages, |
|
.mask_set = __pgprot(0), |
|
.mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW), |
|
.flags = 0}; |
|
|
|
/* |
|
* No alias checking needed for setting not present flag. otherwise, |
|
* we may need to break large pages for 64-bit kernel text |
|
* mappings (this adds to complexity if we want to do this from |
|
* atomic context especially). Let's keep it simple! |
|
*/ |
|
return __change_page_attr_set_clr(&cpa, 0); |
|
} |
|
|
|
int set_direct_map_invalid_noflush(struct page *page) |
|
{ |
|
return __set_pages_np(page, 1); |
|
} |
|
|
|
int set_direct_map_default_noflush(struct page *page) |
|
{ |
|
return __set_pages_p(page, 1); |
|
} |
|
|
|
#ifdef CONFIG_DEBUG_PAGEALLOC |
|
void __kernel_map_pages(struct page *page, int numpages, int enable) |
|
{ |
|
if (PageHighMem(page)) |
|
return; |
|
if (!enable) { |
|
debug_check_no_locks_freed(page_address(page), |
|
numpages * PAGE_SIZE); |
|
} |
|
|
|
/* |
|
* The return value is ignored as the calls cannot fail. |
|
* Large pages for identity mappings are not used at boot time |
|
* and hence no memory allocations during large page split. |
|
*/ |
|
if (enable) |
|
__set_pages_p(page, numpages); |
|
else |
|
__set_pages_np(page, numpages); |
|
|
|
/* |
|
* We should perform an IPI and flush all tlbs, |
|
* but that can deadlock->flush only current cpu. |
|
* Preemption needs to be disabled around __flush_tlb_all() due to |
|
* CR3 reload in __native_flush_tlb(). |
|
*/ |
|
preempt_disable(); |
|
__flush_tlb_all(); |
|
preempt_enable(); |
|
|
|
arch_flush_lazy_mmu_mode(); |
|
} |
|
#endif /* CONFIG_DEBUG_PAGEALLOC */ |
|
|
|
bool kernel_page_present(struct page *page) |
|
{ |
|
unsigned int level; |
|
pte_t *pte; |
|
|
|
if (PageHighMem(page)) |
|
return false; |
|
|
|
pte = lookup_address((unsigned long)page_address(page), &level); |
|
return (pte_val(*pte) & _PAGE_PRESENT); |
|
} |
|
|
|
int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address, |
|
unsigned numpages, unsigned long page_flags) |
|
{ |
|
int retval = -EINVAL; |
|
|
|
struct cpa_data cpa = { |
|
.vaddr = &address, |
|
.pfn = pfn, |
|
.pgd = pgd, |
|
.numpages = numpages, |
|
.mask_set = __pgprot(0), |
|
.mask_clr = __pgprot(~page_flags & (_PAGE_NX|_PAGE_RW)), |
|
.flags = 0, |
|
}; |
|
|
|
WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP"); |
|
|
|
if (!(__supported_pte_mask & _PAGE_NX)) |
|
goto out; |
|
|
|
if (!(page_flags & _PAGE_ENC)) |
|
cpa.mask_clr = pgprot_encrypted(cpa.mask_clr); |
|
|
|
cpa.mask_set = __pgprot(_PAGE_PRESENT | page_flags); |
|
|
|
retval = __change_page_attr_set_clr(&cpa, 0); |
|
__flush_tlb_all(); |
|
|
|
out: |
|
return retval; |
|
} |
|
|
|
/* |
|
* __flush_tlb_all() flushes mappings only on current CPU and hence this |
|
* function shouldn't be used in an SMP environment. Presently, it's used only |
|
* during boot (way before smp_init()) by EFI subsystem and hence is ok. |
|
*/ |
|
int __init kernel_unmap_pages_in_pgd(pgd_t *pgd, unsigned long address, |
|
unsigned long numpages) |
|
{ |
|
int retval; |
|
|
|
/* |
|
* The typical sequence for unmapping is to find a pte through |
|
* lookup_address_in_pgd() (ideally, it should never return NULL because |
|
* the address is already mapped) and change it's protections. As pfn is |
|
* the *target* of a mapping, it's not useful while unmapping. |
|
*/ |
|
struct cpa_data cpa = { |
|
.vaddr = &address, |
|
.pfn = 0, |
|
.pgd = pgd, |
|
.numpages = numpages, |
|
.mask_set = __pgprot(0), |
|
.mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW), |
|
.flags = 0, |
|
}; |
|
|
|
WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP"); |
|
|
|
retval = __change_page_attr_set_clr(&cpa, 0); |
|
__flush_tlb_all(); |
|
|
|
return retval; |
|
} |
|
|
|
/* |
|
* The testcases use internal knowledge of the implementation that shouldn't |
|
* be exposed to the rest of the kernel. Include these directly here. |
|
*/ |
|
#ifdef CONFIG_CPA_DEBUG |
|
#include "cpa-test.c" |
|
#endif
|
|
|