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ab5130186d
As an optimization, cpa_flush() was changed to optionally only flush
the range in @cpa if it was small enough. However, this range does
not include any direct map aliases changed in cpa_process_alias(). So
small set_memory_() calls that touch that alias don't get the direct
map changes flushed. This situation can happen when the virtual
address taking variants are passed an address in vmalloc or modules
space.
In these cases, force a full TLB flush.
Note this issue does not extend to cases where the set_memory_() calls are
passed a direct map address, or page array, etc, as the primary target. In
those cases the direct map would be flushed.
Fixes: 935f583982
("x86/mm/cpa: Optimize cpa_flush_array() TLB invalidation")
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200424105343.GA20730@hirez.programming.kicks-ass.net
2310 lines
56 KiB
C
2310 lines
56 KiB
C
// 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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#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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#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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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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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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/*
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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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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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#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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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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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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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->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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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 *)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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#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)
|
|
{
|
|
static const char *lvltxt[] = {
|
|
[CPA_CONFLICT] = "conflict",
|
|
[CPA_PROTECT] = "protect",
|
|
[CPA_DETECT] = "detect",
|
|
};
|
|
|
|
if (warnlvl > cpa_warn_level || !conflicts(prot, val))
|
|
return;
|
|
|
|
pr_warn("CPA %8s %10s: 0x%016lx - 0x%016lx PFN %lx req %016llx prevent %016llx\n",
|
|
lvltxt[warnlvl], txt, start, end, pfn, (unsigned long long)pgprot_val(prot),
|
|
(unsigned long long)val);
|
|
}
|
|
|
|
/*
|
|
* 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,
|
|
unsigned long lpsize, 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;
|
|
|
|
/*
|
|
* 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);
|
|
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, 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 (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);
|
|
}
|
|
|
|
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 */
|
|
|
|
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
|