--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2002 Andi Kleen, SuSE Labs.
+ * Thanks to Ben LaHaise for precious feedback.
+ */
+#include <linux/highmem.h>
+#include <linux/memblock.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+#include <linux/pfn.h>
+#include <linux/percpu.h>
+#include <linux/gfp.h>
+#include <linux/pci.h>
+#include <linux/vmalloc.h>
+
+#include <asm/e820/api.h>
+#include <asm/processor.h>
+#include <asm/tlbflush.h>
+#include <asm/sections.h>
+#include <asm/setup.h>
+#include <linux/uaccess.h>
+#include <asm/pgalloc.h>
+#include <asm/proto.h>
+#include <asm/memtype.h>
+#include <asm/set_memory.h>
+
+#include "../mm_internal.h"
+
+/*
+ * The current flushing context - we pass it instead of 5 arguments:
+ */
+struct cpa_data {
+ unsigned long *vaddr;
+ pgd_t *pgd;
+ pgprot_t mask_set;
+ pgprot_t mask_clr;
+ unsigned long numpages;
+ unsigned long curpage;
+ unsigned long pfn;
+ unsigned int flags;
+ unsigned int force_split : 1,
+ force_static_prot : 1;
+ struct page **pages;
+};
+
+enum cpa_warn {
+ CPA_CONFLICT,
+ CPA_PROTECT,
+ CPA_DETECT,
+};
+
+static const int cpa_warn_level = CPA_PROTECT;
+
+/*
+ * Serialize cpa() (for !DEBUG_PAGEALLOC which uses large identity mappings)
+ * using cpa_lock. So that we don't allow any other cpu, with stale large tlb
+ * entries change the page attribute in parallel to some other cpu
+ * splitting a large page entry along with changing the attribute.
+ */
+static DEFINE_SPINLOCK(cpa_lock);
+
+#define CPA_FLUSHTLB 1
+#define CPA_ARRAY 2
+#define CPA_PAGES_ARRAY 4
+#define CPA_NO_CHECK_ALIAS 8 /* Do not search for aliases */
+
+#ifdef CONFIG_PROC_FS
+static unsigned long direct_pages_count[PG_LEVEL_NUM];
+
+void update_page_count(int level, unsigned long pages)
+{
+ /* Protect against CPA */
+ spin_lock(&pgd_lock);
+ direct_pages_count[level] += pages;
+ spin_unlock(&pgd_lock);
+}
+
+static void split_page_count(int level)
+{
+ if (direct_pages_count[level] == 0)
+ return;
+
+ direct_pages_count[level]--;
+ direct_pages_count[level - 1] += PTRS_PER_PTE;
+}
+
+void arch_report_meminfo(struct seq_file *m)
+{
+ seq_printf(m, "DirectMap4k: %8lu kB\n",
+ direct_pages_count[PG_LEVEL_4K] << 2);
+#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
+ seq_printf(m, "DirectMap2M: %8lu kB\n",
+ direct_pages_count[PG_LEVEL_2M] << 11);
+#else
+ seq_printf(m, "DirectMap4M: %8lu kB\n",
+ direct_pages_count[PG_LEVEL_2M] << 12);
+#endif
+ if (direct_gbpages)
+ seq_printf(m, "DirectMap1G: %8lu kB\n",
+ direct_pages_count[PG_LEVEL_1G] << 20);
+}
+#else
+static inline void split_page_count(int level) { }
+#endif
+
+#ifdef CONFIG_X86_CPA_STATISTICS
+
+static unsigned long cpa_1g_checked;
+static unsigned long cpa_1g_sameprot;
+static unsigned long cpa_1g_preserved;
+static unsigned long cpa_2m_checked;
+static unsigned long cpa_2m_sameprot;
+static unsigned long cpa_2m_preserved;
+static unsigned long cpa_4k_install;
+
+static inline void cpa_inc_1g_checked(void)
+{
+ cpa_1g_checked++;
+}
+
+static inline void cpa_inc_2m_checked(void)
+{
+ cpa_2m_checked++;
+}
+
+static inline void cpa_inc_4k_install(void)
+{
+ cpa_4k_install++;
+}
+
+static inline void cpa_inc_lp_sameprot(int level)
+{
+ if (level == PG_LEVEL_1G)
+ cpa_1g_sameprot++;
+ else
+ cpa_2m_sameprot++;
+}
+
+static inline void cpa_inc_lp_preserved(int level)
+{
+ if (level == PG_LEVEL_1G)
+ cpa_1g_preserved++;
+ else
+ cpa_2m_preserved++;
+}
+
+static int cpastats_show(struct seq_file *m, void *p)
+{
+ seq_printf(m, "1G pages checked: %16lu\n", cpa_1g_checked);
+ seq_printf(m, "1G pages sameprot: %16lu\n", cpa_1g_sameprot);
+ seq_printf(m, "1G pages preserved: %16lu\n", cpa_1g_preserved);
+ seq_printf(m, "2M pages checked: %16lu\n", cpa_2m_checked);
+ seq_printf(m, "2M pages sameprot: %16lu\n", cpa_2m_sameprot);
+ seq_printf(m, "2M pages preserved: %16lu\n", cpa_2m_preserved);
+ seq_printf(m, "4K pages set-checked: %16lu\n", cpa_4k_install);
+ return 0;
+}
+
+static int cpastats_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, cpastats_show, NULL);
+}
+
+static const struct file_operations cpastats_fops = {
+ .open = cpastats_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int __init cpa_stats_init(void)
+{
+ debugfs_create_file("cpa_stats", S_IRUSR, arch_debugfs_dir, NULL,
+ &cpastats_fops);
+ return 0;
+}
+late_initcall(cpa_stats_init);
+#else
+static inline void cpa_inc_1g_checked(void) { }
+static inline void cpa_inc_2m_checked(void) { }
+static inline void cpa_inc_4k_install(void) { }
+static inline void cpa_inc_lp_sameprot(int level) { }
+static inline void cpa_inc_lp_preserved(int level) { }
+#endif
+
+
+static inline int
+within(unsigned long addr, unsigned long start, unsigned long end)
+{
+ return addr >= start && addr < end;
+}
+
+static inline int
+within_inclusive(unsigned long addr, unsigned long start, unsigned long end)
+{
+ return addr >= start && addr <= end;
+}
+
+#ifdef CONFIG_X86_64
+
+static inline unsigned long highmap_start_pfn(void)
+{
+ return __pa_symbol(_text) >> PAGE_SHIFT;
+}
+
+static inline unsigned long highmap_end_pfn(void)
+{
+ /* Do not reference physical address outside the kernel. */
+ return __pa_symbol(roundup(_brk_end, PMD_SIZE) - 1) >> PAGE_SHIFT;
+}
+
+static bool __cpa_pfn_in_highmap(unsigned long pfn)
+{
+ /*
+ * Kernel text has an alias mapping at a high address, known
+ * here as "highmap".
+ */
+ return within_inclusive(pfn, highmap_start_pfn(), highmap_end_pfn());
+}
+
+#else
+
+static bool __cpa_pfn_in_highmap(unsigned long pfn)
+{
+ /* There is no highmap on 32-bit */
+ return false;
+}
+
+#endif
+
+/*
+ * See set_mce_nospec().
+ *
+ * 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 TLB and cache and the non-canonical address
+ * causes a #GP fault when used by the INVLPG and CLFLUSH instructions.
+ *
+ * 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 fix_addr(unsigned long addr)
+{
+#ifdef CONFIG_X86_64
+ return (long)(addr << 1) >> 1;
+#else
+ return addr;
+#endif
+}
+
+static unsigned long __cpa_addr(struct cpa_data *cpa, unsigned long idx)
+{
+ if (cpa->flags & CPA_PAGES_ARRAY) {
+ struct page *page = cpa->pages[idx];
+
+ if (unlikely(PageHighMem(page)))
+ return 0;
+
+ return (unsigned long)page_address(page);
+ }
+
+ if (cpa->flags & CPA_ARRAY)
+ return cpa->vaddr[idx];
+
+ return *cpa->vaddr + idx * PAGE_SIZE;
+}
+
+/*
+ * Flushing functions
+ */
+
+static void clflush_cache_range_opt(void *vaddr, unsigned int size)
+{
+ const unsigned long clflush_size = boot_cpu_data.x86_clflush_size;
+ void *p = (void *)((unsigned long)vaddr & ~(clflush_size - 1));
+ void *vend = vaddr + size;
+
+ if (p >= vend)
+ return;
+
+ for (; p < vend; p += clflush_size)
+ clflushopt(p);
+}
+
+/**
+ * clflush_cache_range - flush a cache range with clflush
+ * @vaddr: virtual start address
+ * @size: number of bytes to flush
+ *
+ * CLFLUSHOPT is an unordered instruction which needs fencing with MFENCE or
+ * SFENCE to avoid ordering issues.
+ */
+void clflush_cache_range(void *vaddr, unsigned int size)
+{
+ mb();
+ clflush_cache_range_opt(vaddr, size);
+ mb();
+}
+EXPORT_SYMBOL_GPL(clflush_cache_range);
+
+void arch_invalidate_pmem(void *addr, size_t size)
+{
+ clflush_cache_range(addr, size);
+}
+EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
+
+static void __cpa_flush_all(void *arg)
+{
+ unsigned long cache = (unsigned long)arg;
+
+ /*
+ * Flush all to work around Errata in early athlons regarding
+ * large page flushing.
+ */
+ __flush_tlb_all();
+
+ if (cache && boot_cpu_data.x86 >= 4)
+ wbinvd();
+}
+
+static void cpa_flush_all(unsigned long cache)
+{
+ BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
+
+ on_each_cpu(__cpa_flush_all, (void *) cache, 1);
+}
+
+static void __cpa_flush_tlb(void *data)
+{
+ struct cpa_data *cpa = data;
+ unsigned int i;
+
+ for (i = 0; i < cpa->numpages; i++)
+ __flush_tlb_one_kernel(fix_addr(__cpa_addr(cpa, i)));
+}
+
+static void cpa_flush(struct cpa_data *data, int cache)
+{
+ struct cpa_data *cpa = data;
+ unsigned int i;
+
+ BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
+
+ if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) {
+ cpa_flush_all(cache);
+ return;
+ }
+
+ if (cpa->numpages <= tlb_single_page_flush_ceiling)
+ on_each_cpu(__cpa_flush_tlb, cpa, 1);
+ else
+ flush_tlb_all();
+
+ if (!cache)
+ return;
+
+ mb();
+ for (i = 0; i < cpa->numpages; i++) {
+ unsigned long addr = __cpa_addr(cpa, i);
+ unsigned int level;
+
+ pte_t *pte = lookup_address(addr, &level);
+
+ /*
+ * Only flush present addresses:
+ */
+ if (pte && (pte_val(*pte) & _PAGE_PRESENT))
+ clflush_cache_range_opt((void *)fix_addr(addr), PAGE_SIZE);
+ }
+ mb();
+}
+
+static bool overlaps(unsigned long r1_start, unsigned long r1_end,
+ unsigned long r2_start, unsigned long r2_end)
+{
+ return (r1_start <= r2_end && r1_end >= r2_start) ||
+ (r2_start <= r1_end && r2_end >= r1_start);
+}
+
+#ifdef CONFIG_PCI_BIOS
+/*
+ * The BIOS area between 640k and 1Mb needs to be executable for PCI BIOS
+ * based config access (CONFIG_PCI_GOBIOS) support.
+ */
+#define BIOS_PFN PFN_DOWN(BIOS_BEGIN)
+#define BIOS_PFN_END PFN_DOWN(BIOS_END - 1)
+
+static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn)
+{
+ if (pcibios_enabled && overlaps(spfn, epfn, BIOS_PFN, BIOS_PFN_END))
+ return _PAGE_NX;
+ return 0;
+}
+#else
+static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn)
+{
+ return 0;
+}
+#endif
+
+/*
+ * The .rodata section needs to be read-only. Using the pfn catches all
+ * aliases. This also includes __ro_after_init, so do not enforce until
+ * kernel_set_to_readonly is true.
+ */
+static pgprotval_t protect_rodata(unsigned long spfn, unsigned long epfn)
+{
+ unsigned long epfn_ro, spfn_ro = PFN_DOWN(__pa_symbol(__start_rodata));
+
+ /*
+ * Note: __end_rodata is at page aligned and not inclusive, so
+ * subtract 1 to get the last enforced PFN in the rodata area.
+ */
+ epfn_ro = PFN_DOWN(__pa_symbol(__end_rodata)) - 1;
+
+ if (kernel_set_to_readonly && overlaps(spfn, epfn, spfn_ro, epfn_ro))
+ return _PAGE_RW;
+ return 0;
+}
+
+/*
+ * Protect kernel text against becoming non executable by forbidding
+ * _PAGE_NX. This protects only the high kernel mapping (_text -> _etext)
+ * out of which the kernel actually executes. Do not protect the low
+ * mapping.
+ *
+ * This does not cover __inittext since that is gone after boot.
+ */
+static pgprotval_t protect_kernel_text(unsigned long start, unsigned long end)
+{
+ unsigned long t_end = (unsigned long)_etext - 1;
+ unsigned long t_start = (unsigned long)_text;
+
+ if (overlaps(start, end, t_start, t_end))
+ return _PAGE_NX;
+ return 0;
+}
+
+#if defined(CONFIG_X86_64)
+/*
+ * Once the kernel maps the text as RO (kernel_set_to_readonly is set),
+ * kernel text mappings for the large page aligned text, rodata sections
+ * will be always read-only. For the kernel identity mappings covering the
+ * holes caused by this alignment can be anything that user asks.
+ *
+ * This will preserve the large page mappings for kernel text/data at no
+ * extra cost.
+ */
+static pgprotval_t protect_kernel_text_ro(unsigned long start,
+ unsigned long end)
+{
+ unsigned long t_end = (unsigned long)__end_rodata_hpage_align - 1;
+ unsigned long t_start = (unsigned long)_text;
+ unsigned int level;
+
+ if (!kernel_set_to_readonly || !overlaps(start, end, t_start, t_end))
+ return 0;
+ /*
+ * Don't enforce the !RW mapping for the kernel text mapping, if
+ * the current mapping is already using small page mapping. No
+ * need to work hard to preserve large page mappings in this case.
+ *
+ * This also fixes the Linux Xen paravirt guest boot failure caused
+ * by unexpected read-only mappings for kernel identity
+ * mappings. In this paravirt guest case, the kernel text mapping
+ * and the kernel identity mapping share the same page-table pages,
+ * so the protections for kernel text and identity mappings have to
+ * be the same.
+ */
+ if (lookup_address(start, &level) && (level != PG_LEVEL_4K))
+ return _PAGE_RW;
+ return 0;
+}
+#else
+static pgprotval_t protect_kernel_text_ro(unsigned long start,
+ unsigned long end)
+{
+ return 0;
+}
+#endif
+
+static inline bool conflicts(pgprot_t prot, pgprotval_t val)
+{
+ return (pgprot_val(prot) & ~val) != pgprot_val(prot);
+}
+
+static inline void check_conflict(int warnlvl, pgprot_t prot, pgprotval_t val,
+ unsigned long start, unsigned long end,
+ 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;
+
+ 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;
+}
+
+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()
+ * 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
projects / platform / kernel / linux-rpi.git / commitdiff