798 lines
20 KiB
C
798 lines
20 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Virtual Memory Map support
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*
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* (C) 2007 sgi. Christoph Lameter.
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*
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* Virtual memory maps allow VM primitives pfn_to_page, page_to_pfn,
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* virt_to_page, page_address() to be implemented as a base offset
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* calculation without memory access.
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*
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* However, virtual mappings need a page table and TLBs. Many Linux
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* architectures already map their physical space using 1-1 mappings
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* via TLBs. For those arches the virtual memory map is essentially
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* for free if we use the same page size as the 1-1 mappings. In that
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* case the overhead consists of a few additional pages that are
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* allocated to create a view of memory for vmemmap.
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*
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* The architecture is expected to provide a vmemmap_populate() function
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* to instantiate the mapping.
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*/
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#include <linux/mm.h>
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#include <linux/mmzone.h>
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#include <linux/memblock.h>
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#include <linux/memremap.h>
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#include <linux/highmem.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/vmalloc.h>
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#include <linux/sched.h>
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#include <linux/pgtable.h>
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#include <linux/bootmem_info.h>
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#include <asm/dma.h>
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#include <asm/pgalloc.h>
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#include <asm/tlbflush.h>
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#ifdef CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
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/**
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* struct vmemmap_remap_walk - walk vmemmap page table
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*
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* @remap_pte: called for each lowest-level entry (PTE).
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* @nr_walked: the number of walked pte.
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* @reuse_page: the page which is reused for the tail vmemmap pages.
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* @reuse_addr: the virtual address of the @reuse_page page.
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* @vmemmap_pages: the list head of the vmemmap pages that can be freed
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* or is mapped from.
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*/
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struct vmemmap_remap_walk {
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void (*remap_pte)(pte_t *pte, unsigned long addr,
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struct vmemmap_remap_walk *walk);
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unsigned long nr_walked;
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struct page *reuse_page;
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unsigned long reuse_addr;
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struct list_head *vmemmap_pages;
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};
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static int __split_vmemmap_huge_pmd(pmd_t *pmd, unsigned long start)
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{
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pmd_t __pmd;
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int i;
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unsigned long addr = start;
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struct page *page = pmd_page(*pmd);
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pte_t *pgtable = pte_alloc_one_kernel(&init_mm);
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if (!pgtable)
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return -ENOMEM;
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pmd_populate_kernel(&init_mm, &__pmd, pgtable);
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for (i = 0; i < PMD_SIZE / PAGE_SIZE; i++, addr += PAGE_SIZE) {
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pte_t entry, *pte;
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pgprot_t pgprot = PAGE_KERNEL;
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entry = mk_pte(page + i, pgprot);
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pte = pte_offset_kernel(&__pmd, addr);
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set_pte_at(&init_mm, addr, pte, entry);
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}
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spin_lock(&init_mm.page_table_lock);
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if (likely(pmd_leaf(*pmd))) {
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/*
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* Higher order allocations from buddy allocator must be able to
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* be treated as indepdenent small pages (as they can be freed
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* individually).
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*/
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if (!PageReserved(page))
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split_page(page, get_order(PMD_SIZE));
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/* Make pte visible before pmd. See comment in pmd_install(). */
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smp_wmb();
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pmd_populate_kernel(&init_mm, pmd, pgtable);
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flush_tlb_kernel_range(start, start + PMD_SIZE);
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} else {
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pte_free_kernel(&init_mm, pgtable);
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}
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spin_unlock(&init_mm.page_table_lock);
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return 0;
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}
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static int split_vmemmap_huge_pmd(pmd_t *pmd, unsigned long start)
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{
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int leaf;
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spin_lock(&init_mm.page_table_lock);
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leaf = pmd_leaf(*pmd);
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spin_unlock(&init_mm.page_table_lock);
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if (!leaf)
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return 0;
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return __split_vmemmap_huge_pmd(pmd, start);
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}
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static void vmemmap_pte_range(pmd_t *pmd, unsigned long addr,
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unsigned long end,
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struct vmemmap_remap_walk *walk)
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{
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pte_t *pte = pte_offset_kernel(pmd, addr);
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/*
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* The reuse_page is found 'first' in table walk before we start
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* remapping (which is calling @walk->remap_pte).
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*/
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if (!walk->reuse_page) {
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walk->reuse_page = pte_page(*pte);
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/*
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* Because the reuse address is part of the range that we are
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* walking, skip the reuse address range.
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*/
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addr += PAGE_SIZE;
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pte++;
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walk->nr_walked++;
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}
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for (; addr != end; addr += PAGE_SIZE, pte++) {
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walk->remap_pte(pte, addr, walk);
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walk->nr_walked++;
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}
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}
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static int vmemmap_pmd_range(pud_t *pud, unsigned long addr,
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unsigned long end,
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struct vmemmap_remap_walk *walk)
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{
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pmd_t *pmd;
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unsigned long next;
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pmd = pmd_offset(pud, addr);
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do {
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int ret;
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ret = split_vmemmap_huge_pmd(pmd, addr & PMD_MASK);
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if (ret)
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return ret;
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next = pmd_addr_end(addr, end);
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vmemmap_pte_range(pmd, addr, next, walk);
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} while (pmd++, addr = next, addr != end);
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return 0;
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}
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static int vmemmap_pud_range(p4d_t *p4d, unsigned long addr,
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unsigned long end,
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struct vmemmap_remap_walk *walk)
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{
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pud_t *pud;
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unsigned long next;
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pud = pud_offset(p4d, addr);
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do {
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int ret;
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next = pud_addr_end(addr, end);
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ret = vmemmap_pmd_range(pud, addr, next, walk);
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if (ret)
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return ret;
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} while (pud++, addr = next, addr != end);
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return 0;
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}
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static int vmemmap_p4d_range(pgd_t *pgd, unsigned long addr,
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unsigned long end,
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struct vmemmap_remap_walk *walk)
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{
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p4d_t *p4d;
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unsigned long next;
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p4d = p4d_offset(pgd, addr);
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do {
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int ret;
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next = p4d_addr_end(addr, end);
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ret = vmemmap_pud_range(p4d, addr, next, walk);
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if (ret)
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return ret;
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} while (p4d++, addr = next, addr != end);
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return 0;
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}
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static int vmemmap_remap_range(unsigned long start, unsigned long end,
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struct vmemmap_remap_walk *walk)
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{
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unsigned long addr = start;
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unsigned long next;
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pgd_t *pgd;
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VM_BUG_ON(!PAGE_ALIGNED(start));
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VM_BUG_ON(!PAGE_ALIGNED(end));
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pgd = pgd_offset_k(addr);
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do {
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int ret;
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next = pgd_addr_end(addr, end);
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ret = vmemmap_p4d_range(pgd, addr, next, walk);
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if (ret)
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return ret;
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} while (pgd++, addr = next, addr != end);
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/*
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* We only change the mapping of the vmemmap virtual address range
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* [@start + PAGE_SIZE, end), so we only need to flush the TLB which
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* belongs to the range.
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*/
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flush_tlb_kernel_range(start + PAGE_SIZE, end);
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return 0;
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}
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/*
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* Free a vmemmap page. A vmemmap page can be allocated from the memblock
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* allocator or buddy allocator. If the PG_reserved flag is set, it means
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* that it allocated from the memblock allocator, just free it via the
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* free_bootmem_page(). Otherwise, use __free_page().
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*/
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static inline void free_vmemmap_page(struct page *page)
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{
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if (PageReserved(page))
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free_bootmem_page(page);
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else
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__free_page(page);
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}
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/* Free a list of the vmemmap pages */
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static void free_vmemmap_page_list(struct list_head *list)
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{
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struct page *page, *next;
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list_for_each_entry_safe(page, next, list, lru) {
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list_del(&page->lru);
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free_vmemmap_page(page);
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}
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}
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static void vmemmap_remap_pte(pte_t *pte, unsigned long addr,
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struct vmemmap_remap_walk *walk)
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{
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/*
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* Remap the tail pages as read-only to catch illegal write operation
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* to the tail pages.
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*/
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pgprot_t pgprot = PAGE_KERNEL_RO;
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pte_t entry = mk_pte(walk->reuse_page, pgprot);
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struct page *page = pte_page(*pte);
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list_add_tail(&page->lru, walk->vmemmap_pages);
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set_pte_at(&init_mm, addr, pte, entry);
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}
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/*
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* How many struct page structs need to be reset. When we reuse the head
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* struct page, the special metadata (e.g. page->flags or page->mapping)
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* cannot copy to the tail struct page structs. The invalid value will be
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* checked in the free_tail_pages_check(). In order to avoid the message
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* of "corrupted mapping in tail page". We need to reset at least 3 (one
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* head struct page struct and two tail struct page structs) struct page
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* structs.
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*/
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#define NR_RESET_STRUCT_PAGE 3
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static inline void reset_struct_pages(struct page *start)
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{
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int i;
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struct page *from = start + NR_RESET_STRUCT_PAGE;
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for (i = 0; i < NR_RESET_STRUCT_PAGE; i++)
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memcpy(start + i, from, sizeof(*from));
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}
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static void vmemmap_restore_pte(pte_t *pte, unsigned long addr,
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struct vmemmap_remap_walk *walk)
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{
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pgprot_t pgprot = PAGE_KERNEL;
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struct page *page;
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void *to;
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BUG_ON(pte_page(*pte) != walk->reuse_page);
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page = list_first_entry(walk->vmemmap_pages, struct page, lru);
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list_del(&page->lru);
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to = page_to_virt(page);
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copy_page(to, (void *)walk->reuse_addr);
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reset_struct_pages(to);
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set_pte_at(&init_mm, addr, pte, mk_pte(page, pgprot));
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}
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/**
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* vmemmap_remap_free - remap the vmemmap virtual address range [@start, @end)
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* to the page which @reuse is mapped to, then free vmemmap
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* which the range are mapped to.
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* @start: start address of the vmemmap virtual address range that we want
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* to remap.
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* @end: end address of the vmemmap virtual address range that we want to
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* remap.
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* @reuse: reuse address.
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*
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* Return: %0 on success, negative error code otherwise.
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*/
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int vmemmap_remap_free(unsigned long start, unsigned long end,
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unsigned long reuse)
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{
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int ret;
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LIST_HEAD(vmemmap_pages);
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struct vmemmap_remap_walk walk = {
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.remap_pte = vmemmap_remap_pte,
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.reuse_addr = reuse,
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.vmemmap_pages = &vmemmap_pages,
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};
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/*
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* In order to make remapping routine most efficient for the huge pages,
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* the routine of vmemmap page table walking has the following rules
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* (see more details from the vmemmap_pte_range()):
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*
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* - The range [@start, @end) and the range [@reuse, @reuse + PAGE_SIZE)
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* should be continuous.
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* - The @reuse address is part of the range [@reuse, @end) that we are
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* walking which is passed to vmemmap_remap_range().
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* - The @reuse address is the first in the complete range.
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*
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* So we need to make sure that @start and @reuse meet the above rules.
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*/
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BUG_ON(start - reuse != PAGE_SIZE);
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mmap_read_lock(&init_mm);
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ret = vmemmap_remap_range(reuse, end, &walk);
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if (ret && walk.nr_walked) {
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end = reuse + walk.nr_walked * PAGE_SIZE;
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/*
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* vmemmap_pages contains pages from the previous
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* vmemmap_remap_range call which failed. These
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* are pages which were removed from the vmemmap.
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* They will be restored in the following call.
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*/
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walk = (struct vmemmap_remap_walk) {
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.remap_pte = vmemmap_restore_pte,
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.reuse_addr = reuse,
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.vmemmap_pages = &vmemmap_pages,
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};
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vmemmap_remap_range(reuse, end, &walk);
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}
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mmap_read_unlock(&init_mm);
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free_vmemmap_page_list(&vmemmap_pages);
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return ret;
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}
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static int alloc_vmemmap_page_list(unsigned long start, unsigned long end,
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gfp_t gfp_mask, struct list_head *list)
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{
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unsigned long nr_pages = (end - start) >> PAGE_SHIFT;
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int nid = page_to_nid((struct page *)start);
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struct page *page, *next;
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while (nr_pages--) {
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page = alloc_pages_node(nid, gfp_mask, 0);
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if (!page)
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goto out;
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list_add_tail(&page->lru, list);
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}
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return 0;
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out:
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list_for_each_entry_safe(page, next, list, lru)
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__free_pages(page, 0);
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return -ENOMEM;
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}
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/**
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* vmemmap_remap_alloc - remap the vmemmap virtual address range [@start, end)
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* to the page which is from the @vmemmap_pages
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* respectively.
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* @start: start address of the vmemmap virtual address range that we want
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* to remap.
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* @end: end address of the vmemmap virtual address range that we want to
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* remap.
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* @reuse: reuse address.
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* @gfp_mask: GFP flag for allocating vmemmap pages.
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*
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* Return: %0 on success, negative error code otherwise.
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*/
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int vmemmap_remap_alloc(unsigned long start, unsigned long end,
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unsigned long reuse, gfp_t gfp_mask)
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{
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LIST_HEAD(vmemmap_pages);
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struct vmemmap_remap_walk walk = {
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.remap_pte = vmemmap_restore_pte,
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.reuse_addr = reuse,
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.vmemmap_pages = &vmemmap_pages,
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};
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/* See the comment in the vmemmap_remap_free(). */
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BUG_ON(start - reuse != PAGE_SIZE);
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if (alloc_vmemmap_page_list(start, end, gfp_mask, &vmemmap_pages))
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return -ENOMEM;
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mmap_read_lock(&init_mm);
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vmemmap_remap_range(reuse, end, &walk);
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mmap_read_unlock(&init_mm);
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return 0;
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}
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#endif /* CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP */
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/*
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* Allocate a block of memory to be used to back the virtual memory map
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* or to back the page tables that are used to create the mapping.
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* Uses the main allocators if they are available, else bootmem.
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*/
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static void * __ref __earlyonly_bootmem_alloc(int node,
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unsigned long size,
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unsigned long align,
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unsigned long goal)
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{
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return memblock_alloc_try_nid_raw(size, align, goal,
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MEMBLOCK_ALLOC_ACCESSIBLE, node);
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}
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void * __meminit vmemmap_alloc_block(unsigned long size, int node)
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{
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/* If the main allocator is up use that, fallback to bootmem. */
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if (slab_is_available()) {
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gfp_t gfp_mask = GFP_KERNEL|__GFP_RETRY_MAYFAIL|__GFP_NOWARN;
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int order = get_order(size);
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static bool warned;
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struct page *page;
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page = alloc_pages_node(node, gfp_mask, order);
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if (page)
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return page_address(page);
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if (!warned) {
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warn_alloc(gfp_mask & ~__GFP_NOWARN, NULL,
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"vmemmap alloc failure: order:%u", order);
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warned = true;
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}
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return NULL;
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} else
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return __earlyonly_bootmem_alloc(node, size, size,
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__pa(MAX_DMA_ADDRESS));
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}
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static void * __meminit altmap_alloc_block_buf(unsigned long size,
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struct vmem_altmap *altmap);
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/* need to make sure size is all the same during early stage */
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void * __meminit vmemmap_alloc_block_buf(unsigned long size, int node,
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struct vmem_altmap *altmap)
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{
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void *ptr;
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if (altmap)
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return altmap_alloc_block_buf(size, altmap);
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ptr = sparse_buffer_alloc(size);
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if (!ptr)
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ptr = vmemmap_alloc_block(size, node);
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return ptr;
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}
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static unsigned long __meminit vmem_altmap_next_pfn(struct vmem_altmap *altmap)
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{
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return altmap->base_pfn + altmap->reserve + altmap->alloc
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+ altmap->align;
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}
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static unsigned long __meminit vmem_altmap_nr_free(struct vmem_altmap *altmap)
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{
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unsigned long allocated = altmap->alloc + altmap->align;
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if (altmap->free > allocated)
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return altmap->free - allocated;
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return 0;
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}
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static void * __meminit altmap_alloc_block_buf(unsigned long size,
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struct vmem_altmap *altmap)
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{
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unsigned long pfn, nr_pfns, nr_align;
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if (size & ~PAGE_MASK) {
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pr_warn_once("%s: allocations must be multiple of PAGE_SIZE (%ld)\n",
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__func__, size);
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|
return NULL;
|
|
}
|
|
|
|
pfn = vmem_altmap_next_pfn(altmap);
|
|
nr_pfns = size >> PAGE_SHIFT;
|
|
nr_align = 1UL << find_first_bit(&nr_pfns, BITS_PER_LONG);
|
|
nr_align = ALIGN(pfn, nr_align) - pfn;
|
|
if (nr_pfns + nr_align > vmem_altmap_nr_free(altmap))
|
|
return NULL;
|
|
|
|
altmap->alloc += nr_pfns;
|
|
altmap->align += nr_align;
|
|
pfn += nr_align;
|
|
|
|
pr_debug("%s: pfn: %#lx alloc: %ld align: %ld nr: %#lx\n",
|
|
__func__, pfn, altmap->alloc, altmap->align, nr_pfns);
|
|
return __va(__pfn_to_phys(pfn));
|
|
}
|
|
|
|
void __meminit vmemmap_verify(pte_t *pte, int node,
|
|
unsigned long start, unsigned long end)
|
|
{
|
|
unsigned long pfn = pte_pfn(*pte);
|
|
int actual_node = early_pfn_to_nid(pfn);
|
|
|
|
if (node_distance(actual_node, node) > LOCAL_DISTANCE)
|
|
pr_warn_once("[%lx-%lx] potential offnode page_structs\n",
|
|
start, end - 1);
|
|
}
|
|
|
|
pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node,
|
|
struct vmem_altmap *altmap,
|
|
struct page *reuse)
|
|
{
|
|
pte_t *pte = pte_offset_kernel(pmd, addr);
|
|
if (pte_none(*pte)) {
|
|
pte_t entry;
|
|
void *p;
|
|
|
|
if (!reuse) {
|
|
p = vmemmap_alloc_block_buf(PAGE_SIZE, node, altmap);
|
|
if (!p)
|
|
return NULL;
|
|
} else {
|
|
/*
|
|
* When a PTE/PMD entry is freed from the init_mm
|
|
* there's a free_pages() call to this page allocated
|
|
* above. Thus this get_page() is paired with the
|
|
* put_page_testzero() on the freeing path.
|
|
* This can only called by certain ZONE_DEVICE path,
|
|
* and through vmemmap_populate_compound_pages() when
|
|
* slab is available.
|
|
*/
|
|
get_page(reuse);
|
|
p = page_to_virt(reuse);
|
|
}
|
|
entry = pfn_pte(__pa(p) >> PAGE_SHIFT, PAGE_KERNEL);
|
|
set_pte_at(&init_mm, addr, pte, entry);
|
|
}
|
|
return pte;
|
|
}
|
|
|
|
static void * __meminit vmemmap_alloc_block_zero(unsigned long size, int node)
|
|
{
|
|
void *p = vmemmap_alloc_block(size, node);
|
|
|
|
if (!p)
|
|
return NULL;
|
|
memset(p, 0, size);
|
|
|
|
return p;
|
|
}
|
|
|
|
pmd_t * __meminit vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node)
|
|
{
|
|
pmd_t *pmd = pmd_offset(pud, addr);
|
|
if (pmd_none(*pmd)) {
|
|
void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
|
|
if (!p)
|
|
return NULL;
|
|
pmd_populate_kernel(&init_mm, pmd, p);
|
|
}
|
|
return pmd;
|
|
}
|
|
|
|
pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node)
|
|
{
|
|
pud_t *pud = pud_offset(p4d, addr);
|
|
if (pud_none(*pud)) {
|
|
void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
|
|
if (!p)
|
|
return NULL;
|
|
pud_populate(&init_mm, pud, p);
|
|
}
|
|
return pud;
|
|
}
|
|
|
|
p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node)
|
|
{
|
|
p4d_t *p4d = p4d_offset(pgd, addr);
|
|
if (p4d_none(*p4d)) {
|
|
void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
|
|
if (!p)
|
|
return NULL;
|
|
p4d_populate(&init_mm, p4d, p);
|
|
}
|
|
return p4d;
|
|
}
|
|
|
|
pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node)
|
|
{
|
|
pgd_t *pgd = pgd_offset_k(addr);
|
|
if (pgd_none(*pgd)) {
|
|
void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
|
|
if (!p)
|
|
return NULL;
|
|
pgd_populate(&init_mm, pgd, p);
|
|
}
|
|
return pgd;
|
|
}
|
|
|
|
static pte_t * __meminit vmemmap_populate_address(unsigned long addr, int node,
|
|
struct vmem_altmap *altmap,
|
|
struct page *reuse)
|
|
{
|
|
pgd_t *pgd;
|
|
p4d_t *p4d;
|
|
pud_t *pud;
|
|
pmd_t *pmd;
|
|
pte_t *pte;
|
|
|
|
pgd = vmemmap_pgd_populate(addr, node);
|
|
if (!pgd)
|
|
return NULL;
|
|
p4d = vmemmap_p4d_populate(pgd, addr, node);
|
|
if (!p4d)
|
|
return NULL;
|
|
pud = vmemmap_pud_populate(p4d, addr, node);
|
|
if (!pud)
|
|
return NULL;
|
|
pmd = vmemmap_pmd_populate(pud, addr, node);
|
|
if (!pmd)
|
|
return NULL;
|
|
pte = vmemmap_pte_populate(pmd, addr, node, altmap, reuse);
|
|
if (!pte)
|
|
return NULL;
|
|
vmemmap_verify(pte, node, addr, addr + PAGE_SIZE);
|
|
|
|
return pte;
|
|
}
|
|
|
|
static int __meminit vmemmap_populate_range(unsigned long start,
|
|
unsigned long end, int node,
|
|
struct vmem_altmap *altmap,
|
|
struct page *reuse)
|
|
{
|
|
unsigned long addr = start;
|
|
pte_t *pte;
|
|
|
|
for (; addr < end; addr += PAGE_SIZE) {
|
|
pte = vmemmap_populate_address(addr, node, altmap, reuse);
|
|
if (!pte)
|
|
return -ENOMEM;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int __meminit vmemmap_populate_basepages(unsigned long start, unsigned long end,
|
|
int node, struct vmem_altmap *altmap)
|
|
{
|
|
return vmemmap_populate_range(start, end, node, altmap, NULL);
|
|
}
|
|
|
|
/*
|
|
* For compound pages bigger than section size (e.g. x86 1G compound
|
|
* pages with 2M subsection size) fill the rest of sections as tail
|
|
* pages.
|
|
*
|
|
* Note that memremap_pages() resets @nr_range value and will increment
|
|
* it after each range successful onlining. Thus the value or @nr_range
|
|
* at section memmap populate corresponds to the in-progress range
|
|
* being onlined here.
|
|
*/
|
|
static bool __meminit reuse_compound_section(unsigned long start_pfn,
|
|
struct dev_pagemap *pgmap)
|
|
{
|
|
unsigned long nr_pages = pgmap_vmemmap_nr(pgmap);
|
|
unsigned long offset = start_pfn -
|
|
PHYS_PFN(pgmap->ranges[pgmap->nr_range].start);
|
|
|
|
return !IS_ALIGNED(offset, nr_pages) && nr_pages > PAGES_PER_SUBSECTION;
|
|
}
|
|
|
|
static pte_t * __meminit compound_section_tail_page(unsigned long addr)
|
|
{
|
|
pte_t *pte;
|
|
|
|
addr -= PAGE_SIZE;
|
|
|
|
/*
|
|
* Assuming sections are populated sequentially, the previous section's
|
|
* page data can be reused.
|
|
*/
|
|
pte = pte_offset_kernel(pmd_off_k(addr), addr);
|
|
if (!pte)
|
|
return NULL;
|
|
|
|
return pte;
|
|
}
|
|
|
|
static int __meminit vmemmap_populate_compound_pages(unsigned long start_pfn,
|
|
unsigned long start,
|
|
unsigned long end, int node,
|
|
struct dev_pagemap *pgmap)
|
|
{
|
|
unsigned long size, addr;
|
|
pte_t *pte;
|
|
int rc;
|
|
|
|
if (reuse_compound_section(start_pfn, pgmap)) {
|
|
pte = compound_section_tail_page(start);
|
|
if (!pte)
|
|
return -ENOMEM;
|
|
|
|
/*
|
|
* Reuse the page that was populated in the prior iteration
|
|
* with just tail struct pages.
|
|
*/
|
|
return vmemmap_populate_range(start, end, node, NULL,
|
|
pte_page(*pte));
|
|
}
|
|
|
|
size = min(end - start, pgmap_vmemmap_nr(pgmap) * sizeof(struct page));
|
|
for (addr = start; addr < end; addr += size) {
|
|
unsigned long next, last = addr + size;
|
|
|
|
/* Populate the head page vmemmap page */
|
|
pte = vmemmap_populate_address(addr, node, NULL, NULL);
|
|
if (!pte)
|
|
return -ENOMEM;
|
|
|
|
/* Populate the tail pages vmemmap page */
|
|
next = addr + PAGE_SIZE;
|
|
pte = vmemmap_populate_address(next, node, NULL, NULL);
|
|
if (!pte)
|
|
return -ENOMEM;
|
|
|
|
/*
|
|
* Reuse the previous page for the rest of tail pages
|
|
* See layout diagram in Documentation/mm/vmemmap_dedup.rst
|
|
*/
|
|
next += PAGE_SIZE;
|
|
rc = vmemmap_populate_range(next, last, node, NULL,
|
|
pte_page(*pte));
|
|
if (rc)
|
|
return -ENOMEM;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
struct page * __meminit __populate_section_memmap(unsigned long pfn,
|
|
unsigned long nr_pages, int nid, struct vmem_altmap *altmap,
|
|
struct dev_pagemap *pgmap)
|
|
{
|
|
unsigned long start = (unsigned long) pfn_to_page(pfn);
|
|
unsigned long end = start + nr_pages * sizeof(struct page);
|
|
int r;
|
|
|
|
if (WARN_ON_ONCE(!IS_ALIGNED(pfn, PAGES_PER_SUBSECTION) ||
|
|
!IS_ALIGNED(nr_pages, PAGES_PER_SUBSECTION)))
|
|
return NULL;
|
|
|
|
if (is_power_of_2(sizeof(struct page)) &&
|
|
pgmap && pgmap_vmemmap_nr(pgmap) > 1 && !altmap)
|
|
r = vmemmap_populate_compound_pages(pfn, start, end, nid, pgmap);
|
|
else
|
|
r = vmemmap_populate(start, end, nid, altmap);
|
|
|
|
if (r < 0)
|
|
return NULL;
|
|
|
|
return pfn_to_page(pfn);
|
|
}
|