![Linus Torvalds](/assets/img/avatar_default.png)
Pull x86 mm updates from Ingo Molnar: "The main changes in this cycle were: - Update and clean up x86 fault handling, by Andy Lutomirski. - Drop usage of __flush_tlb_all() in kernel_physical_mapping_init() and related fallout, by Dan Williams. - CPA cleanups and reorganization by Peter Zijlstra: simplify the flow and remove a few warts. - Other misc cleanups" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (29 commits) x86/mm/dump_pagetables: Use DEFINE_SHOW_ATTRIBUTE() x86/mm/cpa: Rename @addrinarray to @numpages x86/mm/cpa: Better use CLFLUSHOPT x86/mm/cpa: Fold cpa_flush_range() and cpa_flush_array() into a single cpa_flush() function x86/mm/cpa: Make cpa_data::numpages invariant x86/mm/cpa: Optimize cpa_flush_array() TLB invalidation x86/mm/cpa: Simplify the code after making cpa->vaddr invariant x86/mm/cpa: Make cpa_data::vaddr invariant x86/mm/cpa: Add __cpa_addr() helper x86/mm/cpa: Add ARRAY and PAGES_ARRAY selftests x86/mm: Drop usage of __flush_tlb_all() in kernel_physical_mapping_init() x86/mm: Validate kernel_physical_mapping_init() PTE population generic/pgtable: Introduce set_pte_safe() generic/pgtable: Introduce {p4d,pgd}_same() generic/pgtable: Make {pmd, pud}_same() unconditionally available x86/fault: Clean up the page fault oops decoder a bit x86/fault: Decode page fault OOPSes better x86/vsyscall/64: Use X86_PF constants in the simulated #PF error code x86/oops: Show the correct CS value in show_regs() x86/fault: Don't try to recover from an implicit supervisor access ...
2381 lines
57 KiB
C
2381 lines
57 KiB
C
/*
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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 <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/pat.h>
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#include <asm/set_memory.h>
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#include "mm_internal.h"
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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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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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static const int cpa_warn_level = CPA_PROTECT;
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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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#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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#ifdef CONFIG_PROC_FS
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static unsigned long direct_pages_count[PG_LEVEL_NUM];
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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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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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direct_pages_count[level]--;
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direct_pages_count[level - 1] += PTRS_PER_PTE;
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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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#ifdef CONFIG_X86_CPA_STATISTICS
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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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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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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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static inline void cpa_inc_4k_install(void)
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{
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cpa_4k_install++;
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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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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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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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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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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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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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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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#ifdef CONFIG_X86_64
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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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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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#endif
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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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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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* Flushing functions
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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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if (p >= vend)
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return;
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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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* 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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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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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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* 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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if (cache && boot_cpu_data.x86 >= 4)
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wbinvd();
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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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on_each_cpu(__cpa_flush_all, (void *) cache, 1);
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}
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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(__cpa_addr(cpa, i));
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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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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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if (cpa->numpages <= tlb_single_page_flush_ceiling)
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on_each_cpu(__cpa_flush_tlb, cpa, 1);
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else
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flush_tlb_all();
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if (!cache)
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return;
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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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pte_t *pte = lookup_address(addr, &level);
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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 *)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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#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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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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* 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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* 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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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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* 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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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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#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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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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}
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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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}
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/*
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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.
|
|
*/
|
|
static inline pgprot_t static_protections(pgprot_t prot, unsigned long start,
|
|
unsigned long pfn, unsigned long npg,
|
|
int warnlvl)
|
|
{
|
|
pgprotval_t forbidden, res;
|
|
unsigned long end;
|
|
|
|
/*
|
|
* There is no point in checking RW/NX conflicts when the requested
|
|
* mapping is setting the page !PRESENT.
|
|
*/
|
|
if (!(pgprot_val(prot) & _PAGE_PRESENT))
|
|
return prot;
|
|
|
|
/* Operate on the virtual address */
|
|
end = start + npg * PAGE_SIZE - 1;
|
|
|
|
res = protect_kernel_text(start, end);
|
|
check_conflict(warnlvl, prot, res, start, end, pfn, "Text NX");
|
|
forbidden = res;
|
|
|
|
res = protect_kernel_text_ro(start, end);
|
|
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);
|
|
|
|
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, old_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.
|
|
*/
|
|
old_pte = *kpte;
|
|
/* 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,
|
|
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,
|
|
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;
|
|
|
|
prot = static_protections(ref_prot, address, pfn, npg, 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();
|
|
new_prot = static_protections(new_prot, address, pfn, 1,
|
|
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;
|
|
|
|
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;
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
/*
|
|
* Machine check recovery code needs to change cache mode of poisoned
|
|
* pages to UC to avoid speculative access logging another error. But
|
|
* passing the address of the 1:1 mapping to set_memory_uc() is a fine
|
|
* way to encourage a speculative access. So we cheat and flip the top
|
|
* bit of the address. This works fine for the code that updates the
|
|
* page tables. But at the end of the process we need to flush the cache
|
|
* and the non-canonical address causes a #GP fault when used by the
|
|
* CLFLUSH instruction.
|
|
*
|
|
* But in the common case we already have a canonical address. This code
|
|
* will fix the top bit if needed and is a no-op otherwise.
|
|
*/
|
|
static inline unsigned long make_addr_canonical_again(unsigned long addr)
|
|
{
|
|
#ifdef CONFIG_X86_64
|
|
return (long)(addr << 1) >> 1;
|
|
#else
|
|
return addr;
|
|
#endif
|
|
}
|
|
|
|
|
|
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);
|
|
}
|
|
|
|
int _set_memory_uc(unsigned long addr, int numpages)
|
|
{
|
|
/*
|
|
* for now UC MINUS. see comments in ioremap_nocache()
|
|
* 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_nocache()
|
|
*/
|
|
ret = reserve_memtype(__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:
|
|
free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
|
|
out_err:
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(set_memory_uc);
|
|
|
|
static int _set_memory_array(unsigned long *addr, int numpages,
|
|
enum page_cache_mode new_type)
|
|
{
|
|
enum page_cache_mode set_type;
|
|
int i, j;
|
|
int ret;
|
|
|
|
for (i = 0; i < numpages; i++) {
|
|
ret = reserve_memtype(__pa(addr[i]), __pa(addr[i]) + PAGE_SIZE,
|
|
new_type, NULL);
|
|
if (ret)
|
|
goto out_free;
|
|
}
|
|
|
|
/* 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 = change_page_attr_set(addr, numpages,
|
|
cachemode2pgprot(set_type), 1);
|
|
|
|
if (!ret && new_type == _PAGE_CACHE_MODE_WC)
|
|
ret = change_page_attr_set_clr(addr, numpages,
|
|
cachemode2pgprot(
|
|
_PAGE_CACHE_MODE_WC),
|
|
__pgprot(_PAGE_CACHE_MASK),
|
|
0, CPA_ARRAY, NULL);
|
|
if (ret)
|
|
goto out_free;
|
|
|
|
return 0;
|
|
|
|
out_free:
|
|
for (j = 0; j < i; j++)
|
|
free_memtype(__pa(addr[j]), __pa(addr[j]) + PAGE_SIZE);
|
|
|
|
return ret;
|
|
}
|
|
|
|
int set_memory_array_uc(unsigned long *addr, int numpages)
|
|
{
|
|
return _set_memory_array(addr, numpages, _PAGE_CACHE_MODE_UC_MINUS);
|
|
}
|
|
EXPORT_SYMBOL(set_memory_array_uc);
|
|
|
|
int set_memory_array_wc(unsigned long *addr, int numpages)
|
|
{
|
|
return _set_memory_array(addr, numpages, _PAGE_CACHE_MODE_WC);
|
|
}
|
|
EXPORT_SYMBOL(set_memory_array_wc);
|
|
|
|
int set_memory_array_wt(unsigned long *addr, int numpages)
|
|
{
|
|
return _set_memory_array(addr, numpages, _PAGE_CACHE_MODE_WT);
|
|
}
|
|
EXPORT_SYMBOL_GPL(set_memory_array_wt);
|
|
|
|
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 = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
|
|
_PAGE_CACHE_MODE_WC, NULL);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = _set_memory_wc(addr, numpages);
|
|
if (ret)
|
|
free_memtype(__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_wt(unsigned long addr, int numpages)
|
|
{
|
|
int ret;
|
|
|
|
ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
|
|
_PAGE_CACHE_MODE_WT, NULL);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = _set_memory_wt(addr, numpages);
|
|
if (ret)
|
|
free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(set_memory_wt);
|
|
|
|
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;
|
|
|
|
free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(set_memory_wb);
|
|
|
|
int set_memory_array_wb(unsigned long *addr, int numpages)
|
|
{
|
|
int i;
|
|
int ret;
|
|
|
|
/* WB cache mode is hard wired to all cache attribute bits being 0 */
|
|
ret = change_page_attr_clear(addr, numpages,
|
|
__pgprot(_PAGE_CACHE_MASK), 1);
|
|
if (ret)
|
|
return ret;
|
|
|
|
for (i = 0; i < numpages; i++)
|
|
free_memtype(__pa(addr[i]), __pa(addr[i]) + PAGE_SIZE);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(set_memory_array_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);
|
|
}
|
|
EXPORT_SYMBOL(set_memory_x);
|
|
|
|
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);
|
|
}
|
|
EXPORT_SYMBOL(set_memory_nx);
|
|
|
|
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, 1);
|
|
|
|
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 (reserve_memtype(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;
|
|
free_memtype(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;
|
|
free_memtype(start, end);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(set_pages_array_wb);
|
|
|
|
int set_pages_x(struct page *page, int numpages)
|
|
{
|
|
unsigned long addr = (unsigned long)page_address(page);
|
|
|
|
return set_memory_x(addr, numpages);
|
|
}
|
|
EXPORT_SYMBOL(set_pages_x);
|
|
|
|
int set_pages_nx(struct page *page, int numpages)
|
|
{
|
|
unsigned long addr = (unsigned long)page_address(page);
|
|
|
|
return set_memory_nx(addr, numpages);
|
|
}
|
|
EXPORT_SYMBOL(set_pages_nx);
|
|
|
|
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);
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_PAGEALLOC
|
|
|
|
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);
|
|
}
|
|
|
|
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();
|
|
}
|
|
|
|
#ifdef CONFIG_HIBERNATION
|
|
|
|
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);
|
|
}
|
|
|
|
#endif /* CONFIG_HIBERNATION */
|
|
|
|
#endif /* CONFIG_DEBUG_PAGEALLOC */
|
|
|
|
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(0),
|
|
.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_NX))
|
|
cpa.mask_clr = __pgprot(_PAGE_NX);
|
|
|
|
if (!(page_flags & _PAGE_RW))
|
|
cpa.mask_clr = __pgprot(_PAGE_RW);
|
|
|
|
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 "pageattr-test.c"
|
|
#endif
|