cregit-Linux how code gets into the kernel

Release 4.7 mm/sparse-vmemmap.c

Directory: mm
/*
 * Virtual Memory Map support
 *
 * (C) 2007 sgi. Christoph Lameter.
 *
 * Virtual memory maps allow VM primitives pfn_to_page, page_to_pfn,
 * virt_to_page, page_address() to be implemented as a base offset
 * calculation without memory access.
 *
 * However, virtual mappings need a page table and TLBs. Many Linux
 * architectures already map their physical space using 1-1 mappings
 * via TLBs. For those arches the virtual memory map is essentially
 * for free if we use the same page size as the 1-1 mappings. In that
 * case the overhead consists of a few additional pages that are
 * allocated to create a view of memory for vmemmap.
 *
 * The architecture is expected to provide a vmemmap_populate() function
 * to instantiate the mapping.
 */
#include <linux/mm.h>
#include <linux/mmzone.h>
#include <linux/bootmem.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 <asm/dma.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>

/*
 * Allocate a block of memory to be used to back the virtual memory map
 * or to back the page tables that are used to create the mapping.
 * Uses the main allocators if they are available, else bootmem.
 */


static void * __init_refok __earlyonly_bootmem_alloc(int node, unsigned long size, unsigned long align, unsigned long goal) { return memblock_virt_alloc_try_nid(size, align, goal, BOOTMEM_ALLOC_ACCESSIBLE, node); }

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kamezawa hiroyukikamezawa hiroyuki3286.49%150.00%
santosh shilimkarsantosh shilimkar513.51%150.00%
Total37100.00%2100.00%

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()) { 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)); if (page) return page_address(page); return NULL; } else return __earlyonly_bootmem_alloc(node, size, size, __pa(MAX_DMA_ADDRESS)); }

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PersonTokensPropCommitsCommitProp
christoph lameterchristoph lameter6767.00%125.00%
li shaohuali shaohua2828.00%125.00%
ben hutchingsben hutchings44.00%125.00%
kamezawa hiroyukikamezawa hiroyuki11.00%125.00%
Total100100.00%4100.00%

/* need to make sure size is all the same during early stage */
static void * __meminit alloc_block_buf(unsigned long size, int node) { void *ptr; if (!vmemmap_buf) return vmemmap_alloc_block(size, node); /* take the from buf */ ptr = (void *)ALIGN((unsigned long)vmemmap_buf, size); if (ptr + size > vmemmap_buf_end) return vmemmap_alloc_block(size, node); vmemmap_buf = ptr + size; return ptr; }

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yinghai luyinghai lu7397.33%150.00%
dan williamsdan williams22.67%150.00%
Total75100.00%2100.00%


static unsigned long __meminit vmem_altmap_next_pfn(struct vmem_altmap *altmap) { return altmap->base_pfn + altmap->reserve + altmap->alloc + altmap->align; }

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dan williamsdan williams30100.00%1100.00%
Total30100.00%1100.00%


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; }

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dan williamsdan williams43100.00%1100.00%
Total43100.00%1100.00%

/** * vmem_altmap_alloc - allocate pages from the vmem_altmap reservation * @altmap - reserved page pool for the allocation * @nr_pfns - size (in pages) of the allocation * * Allocations are aligned to the size of the request */
static unsigned long __meminit vmem_altmap_alloc(struct vmem_altmap *altmap, unsigned long nr_pfns) { unsigned long pfn = vmem_altmap_next_pfn(altmap); unsigned long nr_align; 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 ULONG_MAX; altmap->alloc += nr_pfns; altmap->align += nr_align; return pfn + nr_align; }

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dan williamsdan williams84100.00%1100.00%
Total84100.00%1100.00%


static void * __meminit altmap_alloc_block_buf(unsigned long size, struct vmem_altmap *altmap) { unsigned long pfn, nr_pfns; void *ptr; if (size & ~PAGE_MASK) { pr_warn_once("%s: allocations must be multiple of PAGE_SIZE (%ld)\n", __func__, size); return NULL; } nr_pfns = size >> PAGE_SHIFT; pfn = vmem_altmap_alloc(altmap, nr_pfns); if (pfn < ULONG_MAX) ptr = __va(__pfn_to_phys(pfn)); else ptr = NULL; pr_debug("%s: pfn: %#lx alloc: %ld align: %ld nr: %#lx\n", __func__, pfn, altmap->alloc, altmap->align, nr_pfns); return ptr; }

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dan williamsdan williams106100.00%1100.00%
Total106100.00%1100.00%

/* need to make sure size is all the same during early stage */
void * __meminit __vmemmap_alloc_block_buf(unsigned long size, int node, struct vmem_altmap *altmap) { if (altmap) return altmap_alloc_block_buf(size, altmap); return alloc_block_buf(size, node); }

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dan williamsdan williams39100.00%1100.00%
Total39100.00%1100.00%


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("[%lx-%lx] potential offnode page_structs\n", start, end - 1); }

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christoph lameterchristoph lameter5386.89%125.00%
david rientjesdavid rientjes69.84%125.00%
joe perchesjoe perches23.28%250.00%
Total61100.00%4100.00%


pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node) { pte_t *pte = pte_offset_kernel(pmd, addr); if (pte_none(*pte)) { pte_t entry; void *p = alloc_block_buf(PAGE_SIZE, node); if (!p) return NULL; entry = pfn_pte(__pa(p) >> PAGE_SHIFT, PAGE_KERNEL); set_pte_at(&init_mm, addr, pte, entry); } return pte; }

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christoph lameterchristoph lameter7684.44%125.00%
andy whitcroftandy whitcroft1213.33%125.00%
al viroal viro11.11%125.00%
dan williamsdan williams11.11%125.00%
Total90100.00%4100.00%


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); if (!p) return NULL; pmd_populate_kernel(&init_mm, pmd, p); } return pmd; }

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christoph lameterchristoph lameter6591.55%133.33%
andy whitcroftandy whitcroft57.04%133.33%
al viroal viro11.41%133.33%
Total71100.00%3100.00%


pud_t * __meminit vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node) { pud_t *pud = pud_offset(pgd, addr); if (pud_none(*pud)) { void *p = vmemmap_alloc_block(PAGE_SIZE, node); if (!p) return NULL; pud_populate(&init_mm, pud, p); } return pud; }

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christoph lameterchristoph lameter6287.32%133.33%
andy whitcroftandy whitcroft811.27%133.33%
al viroal viro11.41%133.33%
Total71100.00%3100.00%


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); if (!p) return NULL; pgd_populate(&init_mm, pgd, p); } return pgd; }

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andy whitcroftandy whitcroft5178.46%133.33%
christoph lameterchristoph lameter1320.00%133.33%
al viroal viro11.54%133.33%
Total65100.00%3100.00%


int __meminit vmemmap_populate_basepages(unsigned long start, unsigned long end, int node) { unsigned long addr = start; pgd_t *pgd; pud_t *pud; pmd_t *pmd; pte_t *pte; for (; addr < end; addr += PAGE_SIZE) { pgd = vmemmap_pgd_populate(addr, node); if (!pgd) return -ENOMEM; pud = vmemmap_pud_populate(pgd, addr, node); if (!pud) return -ENOMEM; pmd = vmemmap_pmd_populate(pud, addr, node); if (!pmd) return -ENOMEM; pte = vmemmap_pte_populate(pmd, addr, node); if (!pte) return -ENOMEM; vmemmap_verify(pte, node, addr, addr + PAGE_SIZE); } return 0; }

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andy whitcroftandy whitcroft7652.05%133.33%
christoph lameterchristoph lameter6544.52%133.33%
johannes weinerjohannes weiner53.42%133.33%
Total146100.00%3100.00%


struct page * __meminit sparse_mem_map_populate(unsigned long pnum, int nid) { unsigned long start; unsigned long end; struct page *map; map = pfn_to_page(pnum * PAGES_PER_SECTION); start = (unsigned long)map; end = (unsigned long)(map + PAGES_PER_SECTION); if (vmemmap_populate(start, end, nid)) return NULL; return map; }

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christoph lameterchristoph lameter3648.65%133.33%
johannes weinerjohannes weiner3648.65%133.33%
yasunori gotoyasunori goto22.70%133.33%
Total74100.00%3100.00%


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) { unsigned long pnum; unsigned long size = sizeof(struct page) * PAGES_PER_SECTION; void *vmemmap_buf_start; size = ALIGN(size, PMD_SIZE); vmemmap_buf_start = __earlyonly_bootmem_alloc(nodeid, size * map_count, PMD_SIZE, __pa(MAX_DMA_ADDRESS)); if (vmemmap_buf_start) { vmemmap_buf = vmemmap_buf_start; vmemmap_buf_end = vmemmap_buf_start + size * map_count; } for (pnum = pnum_begin; pnum < pnum_end; pnum++) { struct mem_section *ms; if (!present_section_nr(pnum)) continue; map_map[pnum] = sparse_mem_map_populate(pnum, nodeid); if (map_map[pnum]) continue; ms = __nr_to_section(pnum); pr_err("%s: sparsemem memory map backing failed some memory will not be available\n", __func__); ms->section_mem_map = 0; } if (vmemmap_buf_start) { /* need to free left buf */ memblock_free_early(__pa(vmemmap_buf), vmemmap_buf_end - vmemmap_buf); vmemmap_buf = NULL; vmemmap_buf_end = NULL; } }

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yinghai luyinghai lu18598.40%133.33%
joe perchesjoe perches21.06%133.33%
santosh shilimkarsantosh shilimkar10.53%133.33%
Total188100.00%3100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
christoph lameterchristoph lameter46534.94%15.88%
dan williamsdan williams31023.29%15.88%
yinghai luyinghai lu26920.21%15.88%
andy whitcroftandy whitcroft15211.42%15.88%
johannes weinerjohannes weiner413.08%15.88%
kamezawa hiroyukikamezawa hiroyuki332.48%15.88%
li shaohuali shaohua282.10%15.88%
santosh shilimkarsantosh shilimkar60.45%15.88%
david rientjesdavid rientjes60.45%15.88%
ben hutchingsben hutchings40.30%15.88%
joe perchesjoe perches40.30%211.76%
al viroal viro40.30%15.88%
glauber de oliveira costaglauber de oliveira costa30.23%15.88%
tejun heotejun heo30.23%15.88%
yasunori gotoyasunori goto20.15%15.88%
uwe kleine-koeniguwe kleine-koenig10.08%15.88%
Total1331100.00%17100.00%
Directory: mm
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