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-rw-r--r--mm/sparse-vmemmap.c554
1 files changed, 464 insertions, 90 deletions
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index 27eeab3be757..37522d6cb398 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
/*
* Virtual Memory Map support
*
@@ -19,15 +20,27 @@
*/
#include <linux/mm.h>
#include <linux/mmzone.h>
-#include <linux/bootmem.h>
+#include <linux/memblock.h>
+#include <linux/memremap.h>
#include <linux/highmem.h>
#include <linux/slab.h>
#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
@@ -35,199 +48,560 @@
* Uses the main allocators if they are available, else bootmem.
*/
-static void * __init_refok __earlyonly_bootmem_alloc(int node,
+static void * __ref __earlyonly_bootmem_alloc(int node,
unsigned long size,
unsigned long align,
unsigned long goal)
{
- return __alloc_bootmem_node_high(NODE_DATA(node), size, align, goal);
+ return memmap_alloc(size, align, goal, node, false);
}
-static void *vmemmap_buf;
-static void *vmemmap_buf_end;
-
void * __meminit vmemmap_alloc_block(unsigned long size, int node)
{
/* If the main allocator is up use that, fallback to bootmem. */
if (slab_is_available()) {
+ gfp_t gfp_mask = GFP_KERNEL|__GFP_RETRY_MAYFAIL|__GFP_NOWARN;
+ int order = get_order(size);
+ static bool warned;
struct page *page;
- if (node_state(node, N_HIGH_MEMORY))
- page = alloc_pages_node(
- node, GFP_KERNEL | __GFP_ZERO | __GFP_REPEAT,
- get_order(size));
- else
- page = alloc_pages(
- GFP_KERNEL | __GFP_ZERO | __GFP_REPEAT,
- get_order(size));
+ page = alloc_pages_node(node, gfp_mask, order);
if (page)
return page_address(page);
+
+ if (!warned) {
+ warn_alloc(gfp_mask & ~__GFP_NOWARN, NULL,
+ "vmemmap alloc failure: order:%u", order);
+ warned = true;
+ }
return NULL;
} else
return __earlyonly_bootmem_alloc(node, size, size,
__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;
- if (!vmemmap_buf)
- return vmemmap_alloc_block(size, node);
+ if (altmap)
+ return altmap_alloc_block_buf(size, altmap);
- /* take the from buf */
- ptr = (void *)ALIGN((unsigned long)vmemmap_buf, size);
- if (ptr + size > vmemmap_buf_end)
- return vmemmap_alloc_block(size, node);
+ ptr = sparse_buffer_alloc(size);
+ if (!ptr)
+ ptr = vmemmap_alloc_block(size, node);
+ return ptr;
+}
- vmemmap_buf = ptr + size;
+static unsigned long __meminit vmem_altmap_next_pfn(struct vmem_altmap *altmap)
+{
+ return altmap->base_pfn + altmap->reserve + altmap->alloc
+ + altmap->align;
+}
- return ptr;
+static unsigned long __meminit vmem_altmap_nr_free(struct vmem_altmap *altmap)
+{
+ unsigned long allocated = altmap->alloc + altmap->align;
+
+ if (altmap->free > allocated)
+ return altmap->free - allocated;
+ return 0;
+}
+
+static void * __meminit altmap_alloc_block_buf(unsigned long size,
+ struct vmem_altmap *altmap)
+{
+ unsigned long pfn, nr_pfns, nr_align;
+
+ if (size & ~PAGE_MASK) {
+ pr_warn_once("%s: allocations must be multiple of PAGE_SIZE (%ld)\n",
+ __func__, size);
+ 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);
+ unsigned long pfn = pte_pfn(ptep_get(pte));
int actual_node = early_pfn_to_nid(pfn);
if (node_distance(actual_node, node) > LOCAL_DISTANCE)
- printk(KERN_WARNING "[%lx-%lx] potential offnode "
- "page_structs\n", start, end - 1);
+ 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;
}
+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(PAGE_SIZE, 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;
}
-pud_t * __meminit vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node)
+pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node)
{
- pud_t *pud = pud_offset(pgd, addr);
+ pud_t *pud = pud_offset(p4d, addr);
if (pud_none(*pud)) {
- void *p = vmemmap_alloc_block(PAGE_SIZE, 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;
}
+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;
+ pud_init(p);
+ p4d_populate_kernel(addr, 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(PAGE_SIZE, 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;
- pud = vmemmap_pud_populate(pgd, addr, node);
- if (!pud)
+
+ p4d = vmemmap_p4d_populate(pgd, addr, node);
+ if (!p4d)
return -ENOMEM;
- pmd = vmemmap_pmd_populate(pud, addr, node);
- if (!pmd)
+
+ pud = vmemmap_pud_populate(p4d, addr, node);
+ if (!pud)
return -ENOMEM;
- pte = vmemmap_pte_populate(pmd, addr, node);
- if (!pte)
+
+ 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;
- vmemmap_verify(pte, node, addr, addr + PAGE_SIZE);
}
-
return 0;
}
-struct page * __meminit sparse_mem_map_populate(unsigned long pnum, int nid)
+#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 start;
- unsigned long end;
- struct page *map;
+ 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;
+}
- map = pfn_to_page(pnum * PAGES_PER_SECTION);
- start = (unsigned long)map;
- end = (unsigned long)(map + PAGES_PER_SECTION);
+static pte_t * __meminit compound_section_tail_page(unsigned long addr)
+{
+ pte_t *pte;
- if (vmemmap_populate(start, end, nid))
+ 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 map;
+ return pte;
}
-void __init sparse_mem_maps_populate_node(struct page **map_map,
- unsigned long pnum_begin,
- unsigned long pnum_end,
- unsigned long map_count, int nodeid)
+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 pnum;
- unsigned long size = sizeof(struct page) * PAGES_PER_SECTION;
- void *vmemmap_buf_start;
+ unsigned long size, addr;
+ pte_t *pte;
+ int rc;
- size = ALIGN(size, PMD_SIZE);
- vmemmap_buf_start = __earlyonly_bootmem_alloc(nodeid, size * map_count,
- PMD_SIZE, __pa(MAX_DMA_ADDRESS));
+ if (reuse_compound_section(start_pfn, pgmap)) {
+ pte = compound_section_tail_page(start);
+ if (!pte)
+ return -ENOMEM;
- if (vmemmap_buf_start) {
- vmemmap_buf = vmemmap_buf_start;
- vmemmap_buf_end = vmemmap_buf_start + size * map_count;
+ /*
+ * 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);
}
- for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
- struct mem_section *ms;
+ size = min(end - start, pgmap_vmemmap_nr(pgmap) * sizeof(struct page));
+ for (addr = start; addr < end; addr += size) {
+ unsigned long next, last = addr + size;
- if (!present_section_nr(pnum))
- continue;
+ /* Populate the head page vmemmap page */
+ pte = vmemmap_populate_address(addr, node, NULL, -1, 0);
+ if (!pte)
+ return -ENOMEM;
- map_map[pnum] = sparse_mem_map_populate(pnum, nodeid);
- if (map_map[pnum])
- continue;
- ms = __nr_to_section(pnum);
- printk(KERN_ERR "%s: sparsemem memory map backing failed "
- "some memory will not be available.\n", __func__);
- ms->section_mem_map = 0;
- }
+ /* Populate the tail pages vmemmap page */
+ next = addr + PAGE_SIZE;
+ pte = vmemmap_populate_address(next, node, NULL, -1, 0);
+ if (!pte)
+ return -ENOMEM;
- if (vmemmap_buf_start) {
- /* need to free left buf */
- free_bootmem(__pa(vmemmap_buf), vmemmap_buf_end - vmemmap_buf);
- vmemmap_buf = NULL;
- vmemmap_buf_end = NULL;
+ /*
+ * 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;
+}
+
+#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) 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 (vmemmap_can_optimize(altmap, pgmap))
+ 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);
+}
+
+#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