diff options
Diffstat (limited to 'mm/sparse-vmemmap.c')
| -rw-r--r-- | mm/sparse-vmemmap.c | 428 |
1 files changed, 386 insertions, 42 deletions
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c index 7fec05796796..37522d6cb398 100644 --- a/mm/sparse-vmemmap.c +++ b/mm/sparse-vmemmap.c @@ -27,9 +27,20 @@ #include <linux/spinlock.h> #include <linux/vmalloc.h> #include <linux/sched.h> +#include <linux/pgalloc.h> + #include <asm/dma.h> -#include <asm/pgalloc.h> -#include <asm/pgtable.h> +#include <asm/tlbflush.h> + +#include "hugetlb_vmemmap.h" + +/* + * Flags for vmemmap_populate_range and friends. + */ +/* Get a ref on the head page struct page, for ZONE_DEVICE compound pages */ +#define VMEMMAP_POPULATE_PAGEREF 0x0001 + +#include "internal.h" /* * Allocate a block of memory to be used to back the virtual memory map @@ -42,8 +53,7 @@ static void * __ref __earlyonly_bootmem_alloc(int node, unsigned long align, unsigned long goal) { - return memblock_alloc_try_nid_raw(size, align, goal, - MEMBLOCK_ALLOC_ACCESSIBLE, node); + return memmap_alloc(size, align, goal, node, false); } void * __meminit vmemmap_alloc_block(unsigned long size, int node) @@ -70,11 +80,19 @@ void * __meminit vmemmap_alloc_block(unsigned long size, int node) __pa(MAX_DMA_ADDRESS)); } +static void * __meminit altmap_alloc_block_buf(unsigned long size, + struct vmem_altmap *altmap); + /* need to make sure size is all the same during early stage */ -void * __meminit vmemmap_alloc_block_buf(unsigned long size, int node) +void * __meminit vmemmap_alloc_block_buf(unsigned long size, int node, + struct vmem_altmap *altmap) { - void *ptr = sparse_buffer_alloc(size); + void *ptr; + if (altmap) + return altmap_alloc_block_buf(size, altmap); + + ptr = sparse_buffer_alloc(size); if (!ptr) ptr = vmemmap_alloc_block(size, node); return ptr; @@ -95,15 +113,8 @@ static unsigned long __meminit vmem_altmap_nr_free(struct vmem_altmap *altmap) return 0; } -/** - * altmap_alloc_block_buf - allocate pages from the device page map - * @altmap: device page map - * @size: size (in bytes) of the allocation - * - * Allocations are aligned to the size of the request. - */ -void * __meminit altmap_alloc_block_buf(unsigned long size, - struct vmem_altmap *altmap) +static void * __meminit altmap_alloc_block_buf(unsigned long size, + struct vmem_altmap *altmap) { unsigned long pfn, nr_pfns, nr_align; @@ -132,23 +143,42 @@ void * __meminit altmap_alloc_block_buf(unsigned long size, void __meminit vmemmap_verify(pte_t *pte, int node, unsigned long start, unsigned long end) { - unsigned long pfn = pte_pfn(*pte); + unsigned long pfn = pte_pfn(ptep_get(pte)); int actual_node = early_pfn_to_nid(pfn); if (node_distance(actual_node, node) > LOCAL_DISTANCE) - pr_warn("[%lx-%lx] potential offnode page_structs\n", + 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) +pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node, + struct vmem_altmap *altmap, + unsigned long ptpfn, unsigned long flags) { pte_t *pte = pte_offset_kernel(pmd, addr); - if (pte_none(*pte)) { + if (pte_none(ptep_get(pte))) { pte_t entry; - void *p = vmemmap_alloc_block_buf(PAGE_SIZE, node); - if (!p) - return NULL; - entry = pfn_pte(__pa(p) >> PAGE_SHIFT, PAGE_KERNEL); + void *p; + + if (ptpfn == (unsigned long)-1) { + p = vmemmap_alloc_block_buf(PAGE_SIZE, node, altmap); + if (!p) + return NULL; + ptpfn = PHYS_PFN(__pa(p)); + } 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. + */ + if (flags & VMEMMAP_POPULATE_PAGEREF) + get_page(pfn_to_page(ptpfn)); + } + entry = pfn_pte(ptpfn, PAGE_KERNEL); set_pte_at(&init_mm, addr, pte, entry); } return pte; @@ -172,6 +202,7 @@ pmd_t * __meminit vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node) void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node); if (!p) return NULL; + kernel_pte_init(p); pmd_populate_kernel(&init_mm, pmd, p); } return pmd; @@ -184,6 +215,7 @@ pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node) void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node); if (!p) return NULL; + pmd_init(p); pud_populate(&init_mm, pud, p); } return pud; @@ -196,7 +228,8 @@ p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node) void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node); if (!p) return NULL; - p4d_populate(&init_mm, p4d, p); + pud_init(p); + p4d_populate_kernel(addr, p4d, p); } return p4d; } @@ -208,56 +241,367 @@ pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node) void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node); if (!p) return NULL; - pgd_populate(&init_mm, pgd, p); + pgd_populate_kernel(addr, pgd, p); } return pgd; } -int __meminit vmemmap_populate_basepages(unsigned long start, - unsigned long end, int node) +static pte_t * __meminit vmemmap_populate_address(unsigned long addr, int node, + struct vmem_altmap *altmap, + unsigned long ptpfn, + unsigned long flags) { - unsigned long addr = start; 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, ptpfn, flags); + 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, + unsigned long ptpfn, + unsigned long flags) +{ + unsigned long addr = start; + pte_t *pte; + for (; addr < end; addr += PAGE_SIZE) { + pte = vmemmap_populate_address(addr, node, altmap, + ptpfn, flags); + 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, -1, 0); +} + +/* + * Undo populate_hvo, and replace it with a normal base page mapping. + * Used in memory init in case a HVO mapping needs to be undone. + * + * This can happen when it is discovered that a memblock allocated + * hugetlb page spans multiple zones, which can only be verified + * after zones have been initialized. + * + * We know that: + * 1) The first @headsize / PAGE_SIZE vmemmap pages were individually + * allocated through memblock, and mapped. + * + * 2) The rest of the vmemmap pages are mirrors of the last head page. + */ +int __meminit vmemmap_undo_hvo(unsigned long addr, unsigned long end, + int node, unsigned long headsize) +{ + unsigned long maddr, pfn; + pte_t *pte; + int headpages; + + /* + * Should only be called early in boot, so nothing will + * be accessing these page structures. + */ + WARN_ON(!early_boot_irqs_disabled); + + headpages = headsize >> PAGE_SHIFT; + + /* + * Clear mirrored mappings for tail page structs. + */ + for (maddr = addr + headsize; maddr < end; maddr += PAGE_SIZE) { + pte = virt_to_kpte(maddr); + pte_clear(&init_mm, maddr, pte); + } + + /* + * Clear and free mappings for head page and first tail page + * structs. + */ + for (maddr = addr; headpages-- > 0; maddr += PAGE_SIZE) { + pte = virt_to_kpte(maddr); + pfn = pte_pfn(ptep_get(pte)); + pte_clear(&init_mm, maddr, pte); + memblock_phys_free(PFN_PHYS(pfn), PAGE_SIZE); + } + + flush_tlb_kernel_range(addr, end); + + return vmemmap_populate(addr, end, node, NULL); +} + +/* + * Write protect the mirrored tail page structs for HVO. This will be + * called from the hugetlb code when gathering and initializing the + * memblock allocated gigantic pages. The write protect can't be + * done earlier, since it can't be guaranteed that the reserved + * page structures will not be written to during initialization, + * even if CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled. + * + * The PTEs are known to exist, and nothing else should be touching + * these pages. The caller is responsible for any TLB flushing. + */ +void vmemmap_wrprotect_hvo(unsigned long addr, unsigned long end, + int node, unsigned long headsize) +{ + unsigned long maddr; + pte_t *pte; + + for (maddr = addr + headsize; maddr < end; maddr += PAGE_SIZE) { + pte = virt_to_kpte(maddr); + ptep_set_wrprotect(&init_mm, maddr, pte); + } +} + +/* + * Populate vmemmap pages HVO-style. The first page contains the head + * page and needed tail pages, the other ones are mirrors of the first + * page. + */ +int __meminit vmemmap_populate_hvo(unsigned long addr, unsigned long end, + int node, unsigned long headsize) +{ + pte_t *pte; + unsigned long maddr; + + for (maddr = addr; maddr < addr + headsize; maddr += PAGE_SIZE) { + pte = vmemmap_populate_address(maddr, node, NULL, -1, 0); + if (!pte) + return -ENOMEM; + } + + /* + * Reuse the last page struct page mapped above for the rest. + */ + return vmemmap_populate_range(maddr, end, node, NULL, + pte_pfn(ptep_get(pte)), 0); +} + +void __weak __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node, + unsigned long addr, unsigned long next) +{ +} + +int __weak __meminit vmemmap_check_pmd(pmd_t *pmd, int node, + unsigned long addr, unsigned long next) +{ + return 0; +} + +int __meminit vmemmap_populate_hugepages(unsigned long start, unsigned long end, + int node, struct vmem_altmap *altmap) +{ + unsigned long addr; + unsigned long next; + pgd_t *pgd; + p4d_t *p4d; + pud_t *pud; + pmd_t *pmd; + + for (addr = start; addr < end; addr = next) { + next = pmd_addr_end(addr, end); + pgd = vmemmap_pgd_populate(addr, node); if (!pgd) return -ENOMEM; + p4d = vmemmap_p4d_populate(pgd, addr, node); if (!p4d) return -ENOMEM; + pud = vmemmap_pud_populate(p4d, addr, node); if (!pud) return -ENOMEM; - pmd = vmemmap_pmd_populate(pud, addr, node); - if (!pmd) + + pmd = pmd_offset(pud, addr); + if (pmd_none(pmdp_get(pmd))) { + void *p; + + p = vmemmap_alloc_block_buf(PMD_SIZE, node, altmap); + if (p) { + vmemmap_set_pmd(pmd, p, node, addr, next); + continue; + } else if (altmap) { + /* + * No fallback: In any case we care about, the + * altmap should be reasonably sized and aligned + * such that vmemmap_alloc_block_buf() will always + * succeed. For consistency with the PTE case, + * return an error here as failure could indicate + * a configuration issue with the size of the altmap. + */ + return -ENOMEM; + } + } else if (vmemmap_check_pmd(pmd, node, addr, next)) + continue; + if (vmemmap_populate_basepages(addr, next, node, altmap)) return -ENOMEM; - pte = vmemmap_pte_populate(pmd, addr, node); + } + return 0; +} + +#ifndef vmemmap_populate_compound_pages +/* + * 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; - vmemmap_verify(pte, node, addr, addr + PAGE_SIZE); + + /* + * Reuse the page that was populated in the prior iteration + * with just tail struct pages. + */ + return vmemmap_populate_range(start, end, node, NULL, + pte_pfn(ptep_get(pte)), + VMEMMAP_POPULATE_PAGEREF); + } + + 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, -1, 0); + if (!pte) + return -ENOMEM; + + /* Populate the tail pages vmemmap page */ + next = addr + PAGE_SIZE; + pte = vmemmap_populate_address(next, node, NULL, -1, 0); + 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_pfn(ptep_get(pte)), + VMEMMAP_POPULATE_PAGEREF); + if (rc) + return -ENOMEM; } return 0; } -struct page * __meminit sparse_mem_map_populate(unsigned long pnum, int nid, - struct vmem_altmap *altmap) +#endif + +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 end; - struct page *map; + unsigned long start = (unsigned long) pfn_to_page(pfn); + unsigned long end = start + nr_pages * sizeof(struct page); + int r; - map = pfn_to_page(pnum * PAGES_PER_SECTION); - start = (unsigned long)map; - end = (unsigned long)(map + PAGES_PER_SECTION); + if (WARN_ON_ONCE(!IS_ALIGNED(pfn, PAGES_PER_SUBSECTION) || + !IS_ALIGNED(nr_pages, PAGES_PER_SUBSECTION))) + return NULL; + + if (vmemmap_can_optimize(altmap, pgmap)) + r = vmemmap_populate_compound_pages(pfn, start, end, nid, pgmap); + else + r = vmemmap_populate(start, end, nid, altmap); - if (vmemmap_populate(start, end, nid, altmap)) + if (r < 0) return NULL; - return map; + return pfn_to_page(pfn); +} + +#ifdef CONFIG_SPARSEMEM_VMEMMAP_PREINIT +/* + * This is called just before initializing sections for a NUMA node. + * Any special initialization that needs to be done before the + * generic initialization can be done from here. Sections that + * are initialized in hooks called from here will be skipped by + * the generic initialization. + */ +void __init sparse_vmemmap_init_nid_early(int nid) +{ + hugetlb_vmemmap_init_early(nid); +} + +/* + * This is called just before the initialization of page structures + * through memmap_init. Zones are now initialized, so any work that + * needs to be done that needs zone information can be done from + * here. + */ +void __init sparse_vmemmap_init_nid_late(int nid) +{ + hugetlb_vmemmap_init_late(nid); } +#endif |