1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 1993 Linus Torvalds
4 * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
5 * SMP-safe vmalloc/vfree/ioremap, Tigran Aivazian <tigran@veritas.com>, May 2000
6 * Major rework to support vmap/vunmap, Christoph Hellwig, SGI, August 2002
7 * Numa awareness, Christoph Lameter, SGI, June 2005
8 * Improving global KVA allocator, Uladzislau Rezki, Sony, May 2019
11 #include <linux/vmalloc.h>
13 #include <linux/module.h>
14 #include <linux/highmem.h>
15 #include <linux/sched/signal.h>
16 #include <linux/slab.h>
17 #include <linux/spinlock.h>
18 #include <linux/interrupt.h>
19 #include <linux/proc_fs.h>
20 #include <linux/seq_file.h>
21 #include <linux/set_memory.h>
22 #include <linux/debugobjects.h>
23 #include <linux/kallsyms.h>
24 #include <linux/list.h>
25 #include <linux/notifier.h>
26 #include <linux/rbtree.h>
27 #include <linux/xarray.h>
29 #include <linux/rcupdate.h>
30 #include <linux/pfn.h>
31 #include <linux/kmemleak.h>
32 #include <linux/atomic.h>
33 #include <linux/compiler.h>
34 #include <linux/memcontrol.h>
35 #include <linux/llist.h>
36 #include <linux/uio.h>
37 #include <linux/bitops.h>
38 #include <linux/rbtree_augmented.h>
39 #include <linux/overflow.h>
40 #include <linux/pgtable.h>
41 #include <linux/hugetlb.h>
42 #include <linux/sched/mm.h>
43 #include <asm/tlbflush.h>
44 #include <asm/shmparam.h>
46 #define CREATE_TRACE_POINTS
47 #include <trace/events/vmalloc.h>
50 #include "pgalloc-track.h"
52 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
53 static unsigned int __ro_after_init ioremap_max_page_shift = BITS_PER_LONG - 1;
55 static int __init set_nohugeiomap(char *str)
57 ioremap_max_page_shift = PAGE_SHIFT;
60 early_param("nohugeiomap", set_nohugeiomap);
61 #else /* CONFIG_HAVE_ARCH_HUGE_VMAP */
62 static const unsigned int ioremap_max_page_shift = PAGE_SHIFT;
63 #endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
65 #ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
66 static bool __ro_after_init vmap_allow_huge = true;
68 static int __init set_nohugevmalloc(char *str)
70 vmap_allow_huge = false;
73 early_param("nohugevmalloc", set_nohugevmalloc);
74 #else /* CONFIG_HAVE_ARCH_HUGE_VMALLOC */
75 static const bool vmap_allow_huge = false;
76 #endif /* CONFIG_HAVE_ARCH_HUGE_VMALLOC */
78 bool is_vmalloc_addr(const void *x)
80 unsigned long addr = (unsigned long)kasan_reset_tag(x);
82 return addr >= VMALLOC_START && addr < VMALLOC_END;
84 EXPORT_SYMBOL(is_vmalloc_addr);
86 struct vfree_deferred {
87 struct llist_head list;
88 struct work_struct wq;
90 static DEFINE_PER_CPU(struct vfree_deferred, vfree_deferred);
92 /*** Page table manipulation functions ***/
93 static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
94 phys_addr_t phys_addr, pgprot_t prot,
95 unsigned int max_page_shift, pgtbl_mod_mask *mask)
99 unsigned long size = PAGE_SIZE;
101 pfn = phys_addr >> PAGE_SHIFT;
102 pte = pte_alloc_kernel_track(pmd, addr, mask);
106 BUG_ON(!pte_none(*pte));
108 #ifdef CONFIG_HUGETLB_PAGE
109 size = arch_vmap_pte_range_map_size(addr, end, pfn, max_page_shift);
110 if (size != PAGE_SIZE) {
111 pte_t entry = pfn_pte(pfn, prot);
113 entry = arch_make_huge_pte(entry, ilog2(size), 0);
114 set_huge_pte_at(&init_mm, addr, pte, entry);
115 pfn += PFN_DOWN(size);
119 set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
121 } while (pte += PFN_DOWN(size), addr += size, addr != end);
122 *mask |= PGTBL_PTE_MODIFIED;
126 static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
127 phys_addr_t phys_addr, pgprot_t prot,
128 unsigned int max_page_shift)
130 if (max_page_shift < PMD_SHIFT)
133 if (!arch_vmap_pmd_supported(prot))
136 if ((end - addr) != PMD_SIZE)
139 if (!IS_ALIGNED(addr, PMD_SIZE))
142 if (!IS_ALIGNED(phys_addr, PMD_SIZE))
145 if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr))
148 return pmd_set_huge(pmd, phys_addr, prot);
151 static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
152 phys_addr_t phys_addr, pgprot_t prot,
153 unsigned int max_page_shift, pgtbl_mod_mask *mask)
158 pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
162 next = pmd_addr_end(addr, end);
164 if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot,
166 *mask |= PGTBL_PMD_MODIFIED;
170 if (vmap_pte_range(pmd, addr, next, phys_addr, prot, max_page_shift, mask))
172 } while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
176 static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
177 phys_addr_t phys_addr, pgprot_t prot,
178 unsigned int max_page_shift)
180 if (max_page_shift < PUD_SHIFT)
183 if (!arch_vmap_pud_supported(prot))
186 if ((end - addr) != PUD_SIZE)
189 if (!IS_ALIGNED(addr, PUD_SIZE))
192 if (!IS_ALIGNED(phys_addr, PUD_SIZE))
195 if (pud_present(*pud) && !pud_free_pmd_page(pud, addr))
198 return pud_set_huge(pud, phys_addr, prot);
201 static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
202 phys_addr_t phys_addr, pgprot_t prot,
203 unsigned int max_page_shift, pgtbl_mod_mask *mask)
208 pud = pud_alloc_track(&init_mm, p4d, addr, mask);
212 next = pud_addr_end(addr, end);
214 if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot,
216 *mask |= PGTBL_PUD_MODIFIED;
220 if (vmap_pmd_range(pud, addr, next, phys_addr, prot,
221 max_page_shift, mask))
223 } while (pud++, phys_addr += (next - addr), addr = next, addr != end);
227 static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
228 phys_addr_t phys_addr, pgprot_t prot,
229 unsigned int max_page_shift)
231 if (max_page_shift < P4D_SHIFT)
234 if (!arch_vmap_p4d_supported(prot))
237 if ((end - addr) != P4D_SIZE)
240 if (!IS_ALIGNED(addr, P4D_SIZE))
243 if (!IS_ALIGNED(phys_addr, P4D_SIZE))
246 if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr))
249 return p4d_set_huge(p4d, phys_addr, prot);
252 static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
253 phys_addr_t phys_addr, pgprot_t prot,
254 unsigned int max_page_shift, pgtbl_mod_mask *mask)
259 p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
263 next = p4d_addr_end(addr, end);
265 if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot,
267 *mask |= PGTBL_P4D_MODIFIED;
271 if (vmap_pud_range(p4d, addr, next, phys_addr, prot,
272 max_page_shift, mask))
274 } while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
278 static int vmap_range_noflush(unsigned long addr, unsigned long end,
279 phys_addr_t phys_addr, pgprot_t prot,
280 unsigned int max_page_shift)
286 pgtbl_mod_mask mask = 0;
292 pgd = pgd_offset_k(addr);
294 next = pgd_addr_end(addr, end);
295 err = vmap_p4d_range(pgd, addr, next, phys_addr, prot,
296 max_page_shift, &mask);
299 } while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
301 if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
302 arch_sync_kernel_mappings(start, end);
307 int ioremap_page_range(unsigned long addr, unsigned long end,
308 phys_addr_t phys_addr, pgprot_t prot)
312 err = vmap_range_noflush(addr, end, phys_addr, pgprot_nx(prot),
313 ioremap_max_page_shift);
314 flush_cache_vmap(addr, end);
316 err = kmsan_ioremap_page_range(addr, end, phys_addr, prot,
317 ioremap_max_page_shift);
321 static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
322 pgtbl_mod_mask *mask)
326 pte = pte_offset_kernel(pmd, addr);
328 pte_t ptent = ptep_get_and_clear(&init_mm, addr, pte);
329 WARN_ON(!pte_none(ptent) && !pte_present(ptent));
330 } while (pte++, addr += PAGE_SIZE, addr != end);
331 *mask |= PGTBL_PTE_MODIFIED;
334 static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
335 pgtbl_mod_mask *mask)
341 pmd = pmd_offset(pud, addr);
343 next = pmd_addr_end(addr, end);
345 cleared = pmd_clear_huge(pmd);
346 if (cleared || pmd_bad(*pmd))
347 *mask |= PGTBL_PMD_MODIFIED;
351 if (pmd_none_or_clear_bad(pmd))
353 vunmap_pte_range(pmd, addr, next, mask);
356 } while (pmd++, addr = next, addr != end);
359 static void vunmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
360 pgtbl_mod_mask *mask)
366 pud = pud_offset(p4d, addr);
368 next = pud_addr_end(addr, end);
370 cleared = pud_clear_huge(pud);
371 if (cleared || pud_bad(*pud))
372 *mask |= PGTBL_PUD_MODIFIED;
376 if (pud_none_or_clear_bad(pud))
378 vunmap_pmd_range(pud, addr, next, mask);
379 } while (pud++, addr = next, addr != end);
382 static void vunmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
383 pgtbl_mod_mask *mask)
388 p4d = p4d_offset(pgd, addr);
390 next = p4d_addr_end(addr, end);
394 *mask |= PGTBL_P4D_MODIFIED;
396 if (p4d_none_or_clear_bad(p4d))
398 vunmap_pud_range(p4d, addr, next, mask);
399 } while (p4d++, addr = next, addr != end);
403 * vunmap_range_noflush is similar to vunmap_range, but does not
404 * flush caches or TLBs.
406 * The caller is responsible for calling flush_cache_vmap() before calling
407 * this function, and flush_tlb_kernel_range after it has returned
408 * successfully (and before the addresses are expected to cause a page fault
409 * or be re-mapped for something else, if TLB flushes are being delayed or
412 * This is an internal function only. Do not use outside mm/.
414 void __vunmap_range_noflush(unsigned long start, unsigned long end)
418 unsigned long addr = start;
419 pgtbl_mod_mask mask = 0;
422 pgd = pgd_offset_k(addr);
424 next = pgd_addr_end(addr, end);
426 mask |= PGTBL_PGD_MODIFIED;
427 if (pgd_none_or_clear_bad(pgd))
429 vunmap_p4d_range(pgd, addr, next, &mask);
430 } while (pgd++, addr = next, addr != end);
432 if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
433 arch_sync_kernel_mappings(start, end);
436 void vunmap_range_noflush(unsigned long start, unsigned long end)
438 kmsan_vunmap_range_noflush(start, end);
439 __vunmap_range_noflush(start, end);
443 * vunmap_range - unmap kernel virtual addresses
444 * @addr: start of the VM area to unmap
445 * @end: end of the VM area to unmap (non-inclusive)
447 * Clears any present PTEs in the virtual address range, flushes TLBs and
448 * caches. Any subsequent access to the address before it has been re-mapped
451 void vunmap_range(unsigned long addr, unsigned long end)
453 flush_cache_vunmap(addr, end);
454 vunmap_range_noflush(addr, end);
455 flush_tlb_kernel_range(addr, end);
458 static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
459 unsigned long end, pgprot_t prot, struct page **pages, int *nr,
460 pgtbl_mod_mask *mask)
465 * nr is a running index into the array which helps higher level
466 * callers keep track of where we're up to.
469 pte = pte_alloc_kernel_track(pmd, addr, mask);
473 struct page *page = pages[*nr];
475 if (WARN_ON(!pte_none(*pte)))
479 if (WARN_ON(!pfn_valid(page_to_pfn(page))))
482 set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
484 } while (pte++, addr += PAGE_SIZE, addr != end);
485 *mask |= PGTBL_PTE_MODIFIED;
489 static int vmap_pages_pmd_range(pud_t *pud, unsigned long addr,
490 unsigned long end, pgprot_t prot, struct page **pages, int *nr,
491 pgtbl_mod_mask *mask)
496 pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
500 next = pmd_addr_end(addr, end);
501 if (vmap_pages_pte_range(pmd, addr, next, prot, pages, nr, mask))
503 } while (pmd++, addr = next, addr != end);
507 static int vmap_pages_pud_range(p4d_t *p4d, unsigned long addr,
508 unsigned long end, pgprot_t prot, struct page **pages, int *nr,
509 pgtbl_mod_mask *mask)
514 pud = pud_alloc_track(&init_mm, p4d, addr, mask);
518 next = pud_addr_end(addr, end);
519 if (vmap_pages_pmd_range(pud, addr, next, prot, pages, nr, mask))
521 } while (pud++, addr = next, addr != end);
525 static int vmap_pages_p4d_range(pgd_t *pgd, unsigned long addr,
526 unsigned long end, pgprot_t prot, struct page **pages, int *nr,
527 pgtbl_mod_mask *mask)
532 p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
536 next = p4d_addr_end(addr, end);
537 if (vmap_pages_pud_range(p4d, addr, next, prot, pages, nr, mask))
539 } while (p4d++, addr = next, addr != end);
543 static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end,
544 pgprot_t prot, struct page **pages)
546 unsigned long start = addr;
551 pgtbl_mod_mask mask = 0;
554 pgd = pgd_offset_k(addr);
556 next = pgd_addr_end(addr, end);
558 mask |= PGTBL_PGD_MODIFIED;
559 err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, &mask);
562 } while (pgd++, addr = next, addr != end);
564 if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
565 arch_sync_kernel_mappings(start, end);
571 * vmap_pages_range_noflush is similar to vmap_pages_range, but does not
574 * The caller is responsible for calling flush_cache_vmap() after this
575 * function returns successfully and before the addresses are accessed.
577 * This is an internal function only. Do not use outside mm/.
579 int __vmap_pages_range_noflush(unsigned long addr, unsigned long end,
580 pgprot_t prot, struct page **pages, unsigned int page_shift)
582 unsigned int i, nr = (end - addr) >> PAGE_SHIFT;
584 WARN_ON(page_shift < PAGE_SHIFT);
586 if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMALLOC) ||
587 page_shift == PAGE_SHIFT)
588 return vmap_small_pages_range_noflush(addr, end, prot, pages);
590 for (i = 0; i < nr; i += 1U << (page_shift - PAGE_SHIFT)) {
593 err = vmap_range_noflush(addr, addr + (1UL << page_shift),
594 page_to_phys(pages[i]), prot,
599 addr += 1UL << page_shift;
605 int vmap_pages_range_noflush(unsigned long addr, unsigned long end,
606 pgprot_t prot, struct page **pages, unsigned int page_shift)
608 int ret = kmsan_vmap_pages_range_noflush(addr, end, prot, pages,
613 return __vmap_pages_range_noflush(addr, end, prot, pages, page_shift);
617 * vmap_pages_range - map pages to a kernel virtual address
618 * @addr: start of the VM area to map
619 * @end: end of the VM area to map (non-inclusive)
620 * @prot: page protection flags to use
621 * @pages: pages to map (always PAGE_SIZE pages)
622 * @page_shift: maximum shift that the pages may be mapped with, @pages must
623 * be aligned and contiguous up to at least this shift.
626 * 0 on success, -errno on failure.
628 static int vmap_pages_range(unsigned long addr, unsigned long end,
629 pgprot_t prot, struct page **pages, unsigned int page_shift)
633 err = vmap_pages_range_noflush(addr, end, prot, pages, page_shift);
634 flush_cache_vmap(addr, end);
638 int is_vmalloc_or_module_addr(const void *x)
641 * ARM, x86-64 and sparc64 put modules in a special place,
642 * and fall back on vmalloc() if that fails. Others
643 * just put it in the vmalloc space.
645 #if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
646 unsigned long addr = (unsigned long)kasan_reset_tag(x);
647 if (addr >= MODULES_VADDR && addr < MODULES_END)
650 return is_vmalloc_addr(x);
652 EXPORT_SYMBOL_GPL(is_vmalloc_or_module_addr);
655 * Walk a vmap address to the struct page it maps. Huge vmap mappings will
656 * return the tail page that corresponds to the base page address, which
657 * matches small vmap mappings.
659 struct page *vmalloc_to_page(const void *vmalloc_addr)
661 unsigned long addr = (unsigned long) vmalloc_addr;
662 struct page *page = NULL;
663 pgd_t *pgd = pgd_offset_k(addr);
670 * XXX we might need to change this if we add VIRTUAL_BUG_ON for
671 * architectures that do not vmalloc module space
673 VIRTUAL_BUG_ON(!is_vmalloc_or_module_addr(vmalloc_addr));
677 if (WARN_ON_ONCE(pgd_leaf(*pgd)))
678 return NULL; /* XXX: no allowance for huge pgd */
679 if (WARN_ON_ONCE(pgd_bad(*pgd)))
682 p4d = p4d_offset(pgd, addr);
686 return p4d_page(*p4d) + ((addr & ~P4D_MASK) >> PAGE_SHIFT);
687 if (WARN_ON_ONCE(p4d_bad(*p4d)))
690 pud = pud_offset(p4d, addr);
694 return pud_page(*pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
695 if (WARN_ON_ONCE(pud_bad(*pud)))
698 pmd = pmd_offset(pud, addr);
702 return pmd_page(*pmd) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
703 if (WARN_ON_ONCE(pmd_bad(*pmd)))
706 ptep = pte_offset_map(pmd, addr);
708 if (pte_present(pte))
709 page = pte_page(pte);
714 EXPORT_SYMBOL(vmalloc_to_page);
717 * Map a vmalloc()-space virtual address to the physical page frame number.
719 unsigned long vmalloc_to_pfn(const void *vmalloc_addr)
721 return page_to_pfn(vmalloc_to_page(vmalloc_addr));
723 EXPORT_SYMBOL(vmalloc_to_pfn);
726 /*** Global kva allocator ***/
728 #define DEBUG_AUGMENT_PROPAGATE_CHECK 0
729 #define DEBUG_AUGMENT_LOWEST_MATCH_CHECK 0
732 static DEFINE_SPINLOCK(vmap_area_lock);
733 static DEFINE_SPINLOCK(free_vmap_area_lock);
734 /* Export for kexec only */
735 LIST_HEAD(vmap_area_list);
736 static struct rb_root vmap_area_root = RB_ROOT;
737 static bool vmap_initialized __read_mostly;
739 static struct rb_root purge_vmap_area_root = RB_ROOT;
740 static LIST_HEAD(purge_vmap_area_list);
741 static DEFINE_SPINLOCK(purge_vmap_area_lock);
744 * This kmem_cache is used for vmap_area objects. Instead of
745 * allocating from slab we reuse an object from this cache to
746 * make things faster. Especially in "no edge" splitting of
749 static struct kmem_cache *vmap_area_cachep;
752 * This linked list is used in pair with free_vmap_area_root.
753 * It gives O(1) access to prev/next to perform fast coalescing.
755 static LIST_HEAD(free_vmap_area_list);
758 * This augment red-black tree represents the free vmap space.
759 * All vmap_area objects in this tree are sorted by va->va_start
760 * address. It is used for allocation and merging when a vmap
761 * object is released.
763 * Each vmap_area node contains a maximum available free block
764 * of its sub-tree, right or left. Therefore it is possible to
765 * find a lowest match of free area.
767 static struct rb_root free_vmap_area_root = RB_ROOT;
770 * Preload a CPU with one object for "no edge" split case. The
771 * aim is to get rid of allocations from the atomic context, thus
772 * to use more permissive allocation masks.
774 static DEFINE_PER_CPU(struct vmap_area *, ne_fit_preload_node);
776 static __always_inline unsigned long
777 va_size(struct vmap_area *va)
779 return (va->va_end - va->va_start);
782 static __always_inline unsigned long
783 get_subtree_max_size(struct rb_node *node)
785 struct vmap_area *va;
787 va = rb_entry_safe(node, struct vmap_area, rb_node);
788 return va ? va->subtree_max_size : 0;
791 RB_DECLARE_CALLBACKS_MAX(static, free_vmap_area_rb_augment_cb,
792 struct vmap_area, rb_node, unsigned long, subtree_max_size, va_size)
794 static void purge_vmap_area_lazy(void);
795 static BLOCKING_NOTIFIER_HEAD(vmap_notify_list);
796 static void drain_vmap_area_work(struct work_struct *work);
797 static DECLARE_WORK(drain_vmap_work, drain_vmap_area_work);
799 static atomic_long_t nr_vmalloc_pages;
801 unsigned long vmalloc_nr_pages(void)
803 return atomic_long_read(&nr_vmalloc_pages);
806 /* Look up the first VA which satisfies addr < va_end, NULL if none. */
807 static struct vmap_area *find_vmap_area_exceed_addr(unsigned long addr)
809 struct vmap_area *va = NULL;
810 struct rb_node *n = vmap_area_root.rb_node;
812 addr = (unsigned long)kasan_reset_tag((void *)addr);
815 struct vmap_area *tmp;
817 tmp = rb_entry(n, struct vmap_area, rb_node);
818 if (tmp->va_end > addr) {
820 if (tmp->va_start <= addr)
831 static struct vmap_area *__find_vmap_area(unsigned long addr, struct rb_root *root)
833 struct rb_node *n = root->rb_node;
835 addr = (unsigned long)kasan_reset_tag((void *)addr);
838 struct vmap_area *va;
840 va = rb_entry(n, struct vmap_area, rb_node);
841 if (addr < va->va_start)
843 else if (addr >= va->va_end)
853 * This function returns back addresses of parent node
854 * and its left or right link for further processing.
856 * Otherwise NULL is returned. In that case all further
857 * steps regarding inserting of conflicting overlap range
858 * have to be declined and actually considered as a bug.
860 static __always_inline struct rb_node **
861 find_va_links(struct vmap_area *va,
862 struct rb_root *root, struct rb_node *from,
863 struct rb_node **parent)
865 struct vmap_area *tmp_va;
866 struct rb_node **link;
869 link = &root->rb_node;
870 if (unlikely(!*link)) {
879 * Go to the bottom of the tree. When we hit the last point
880 * we end up with parent rb_node and correct direction, i name
881 * it link, where the new va->rb_node will be attached to.
884 tmp_va = rb_entry(*link, struct vmap_area, rb_node);
887 * During the traversal we also do some sanity check.
888 * Trigger the BUG() if there are sides(left/right)
891 if (va->va_end <= tmp_va->va_start)
892 link = &(*link)->rb_left;
893 else if (va->va_start >= tmp_va->va_end)
894 link = &(*link)->rb_right;
896 WARN(1, "vmalloc bug: 0x%lx-0x%lx overlaps with 0x%lx-0x%lx\n",
897 va->va_start, va->va_end, tmp_va->va_start, tmp_va->va_end);
903 *parent = &tmp_va->rb_node;
907 static __always_inline struct list_head *
908 get_va_next_sibling(struct rb_node *parent, struct rb_node **link)
910 struct list_head *list;
912 if (unlikely(!parent))
914 * The red-black tree where we try to find VA neighbors
915 * before merging or inserting is empty, i.e. it means
916 * there is no free vmap space. Normally it does not
917 * happen but we handle this case anyway.
921 list = &rb_entry(parent, struct vmap_area, rb_node)->list;
922 return (&parent->rb_right == link ? list->next : list);
925 static __always_inline void
926 __link_va(struct vmap_area *va, struct rb_root *root,
927 struct rb_node *parent, struct rb_node **link,
928 struct list_head *head, bool augment)
931 * VA is still not in the list, but we can
932 * identify its future previous list_head node.
934 if (likely(parent)) {
935 head = &rb_entry(parent, struct vmap_area, rb_node)->list;
936 if (&parent->rb_right != link)
940 /* Insert to the rb-tree */
941 rb_link_node(&va->rb_node, parent, link);
944 * Some explanation here. Just perform simple insertion
945 * to the tree. We do not set va->subtree_max_size to
946 * its current size before calling rb_insert_augmented().
947 * It is because we populate the tree from the bottom
948 * to parent levels when the node _is_ in the tree.
950 * Therefore we set subtree_max_size to zero after insertion,
951 * to let __augment_tree_propagate_from() puts everything to
952 * the correct order later on.
954 rb_insert_augmented(&va->rb_node,
955 root, &free_vmap_area_rb_augment_cb);
956 va->subtree_max_size = 0;
958 rb_insert_color(&va->rb_node, root);
961 /* Address-sort this list */
962 list_add(&va->list, head);
965 static __always_inline void
966 link_va(struct vmap_area *va, struct rb_root *root,
967 struct rb_node *parent, struct rb_node **link,
968 struct list_head *head)
970 __link_va(va, root, parent, link, head, false);
973 static __always_inline void
974 link_va_augment(struct vmap_area *va, struct rb_root *root,
975 struct rb_node *parent, struct rb_node **link,
976 struct list_head *head)
978 __link_va(va, root, parent, link, head, true);
981 static __always_inline void
982 __unlink_va(struct vmap_area *va, struct rb_root *root, bool augment)
984 if (WARN_ON(RB_EMPTY_NODE(&va->rb_node)))
988 rb_erase_augmented(&va->rb_node,
989 root, &free_vmap_area_rb_augment_cb);
991 rb_erase(&va->rb_node, root);
993 list_del_init(&va->list);
994 RB_CLEAR_NODE(&va->rb_node);
997 static __always_inline void
998 unlink_va(struct vmap_area *va, struct rb_root *root)
1000 __unlink_va(va, root, false);
1003 static __always_inline void
1004 unlink_va_augment(struct vmap_area *va, struct rb_root *root)
1006 __unlink_va(va, root, true);
1009 #if DEBUG_AUGMENT_PROPAGATE_CHECK
1011 * Gets called when remove the node and rotate.
1013 static __always_inline unsigned long
1014 compute_subtree_max_size(struct vmap_area *va)
1016 return max3(va_size(va),
1017 get_subtree_max_size(va->rb_node.rb_left),
1018 get_subtree_max_size(va->rb_node.rb_right));
1022 augment_tree_propagate_check(void)
1024 struct vmap_area *va;
1025 unsigned long computed_size;
1027 list_for_each_entry(va, &free_vmap_area_list, list) {
1028 computed_size = compute_subtree_max_size(va);
1029 if (computed_size != va->subtree_max_size)
1030 pr_emerg("tree is corrupted: %lu, %lu\n",
1031 va_size(va), va->subtree_max_size);
1037 * This function populates subtree_max_size from bottom to upper
1038 * levels starting from VA point. The propagation must be done
1039 * when VA size is modified by changing its va_start/va_end. Or
1040 * in case of newly inserting of VA to the tree.
1042 * It means that __augment_tree_propagate_from() must be called:
1043 * - After VA has been inserted to the tree(free path);
1044 * - After VA has been shrunk(allocation path);
1045 * - After VA has been increased(merging path).
1047 * Please note that, it does not mean that upper parent nodes
1048 * and their subtree_max_size are recalculated all the time up
1057 * For example if we modify the node 4, shrinking it to 2, then
1058 * no any modification is required. If we shrink the node 2 to 1
1059 * its subtree_max_size is updated only, and set to 1. If we shrink
1060 * the node 8 to 6, then its subtree_max_size is set to 6 and parent
1061 * node becomes 4--6.
1063 static __always_inline void
1064 augment_tree_propagate_from(struct vmap_area *va)
1067 * Populate the tree from bottom towards the root until
1068 * the calculated maximum available size of checked node
1069 * is equal to its current one.
1071 free_vmap_area_rb_augment_cb_propagate(&va->rb_node, NULL);
1073 #if DEBUG_AUGMENT_PROPAGATE_CHECK
1074 augment_tree_propagate_check();
1079 insert_vmap_area(struct vmap_area *va,
1080 struct rb_root *root, struct list_head *head)
1082 struct rb_node **link;
1083 struct rb_node *parent;
1085 link = find_va_links(va, root, NULL, &parent);
1087 link_va(va, root, parent, link, head);
1091 insert_vmap_area_augment(struct vmap_area *va,
1092 struct rb_node *from, struct rb_root *root,
1093 struct list_head *head)
1095 struct rb_node **link;
1096 struct rb_node *parent;
1099 link = find_va_links(va, NULL, from, &parent);
1101 link = find_va_links(va, root, NULL, &parent);
1104 link_va_augment(va, root, parent, link, head);
1105 augment_tree_propagate_from(va);
1110 * Merge de-allocated chunk of VA memory with previous
1111 * and next free blocks. If coalesce is not done a new
1112 * free area is inserted. If VA has been merged, it is
1115 * Please note, it can return NULL in case of overlap
1116 * ranges, followed by WARN() report. Despite it is a
1117 * buggy behaviour, a system can be alive and keep
1120 static __always_inline struct vmap_area *
1121 __merge_or_add_vmap_area(struct vmap_area *va,
1122 struct rb_root *root, struct list_head *head, bool augment)
1124 struct vmap_area *sibling;
1125 struct list_head *next;
1126 struct rb_node **link;
1127 struct rb_node *parent;
1128 bool merged = false;
1131 * Find a place in the tree where VA potentially will be
1132 * inserted, unless it is merged with its sibling/siblings.
1134 link = find_va_links(va, root, NULL, &parent);
1139 * Get next node of VA to check if merging can be done.
1141 next = get_va_next_sibling(parent, link);
1142 if (unlikely(next == NULL))
1148 * |<------VA------>|<-----Next----->|
1153 sibling = list_entry(next, struct vmap_area, list);
1154 if (sibling->va_start == va->va_end) {
1155 sibling->va_start = va->va_start;
1157 /* Free vmap_area object. */
1158 kmem_cache_free(vmap_area_cachep, va);
1160 /* Point to the new merged area. */
1169 * |<-----Prev----->|<------VA------>|
1173 if (next->prev != head) {
1174 sibling = list_entry(next->prev, struct vmap_area, list);
1175 if (sibling->va_end == va->va_start) {
1177 * If both neighbors are coalesced, it is important
1178 * to unlink the "next" node first, followed by merging
1179 * with "previous" one. Otherwise the tree might not be
1180 * fully populated if a sibling's augmented value is
1181 * "normalized" because of rotation operations.
1184 __unlink_va(va, root, augment);
1186 sibling->va_end = va->va_end;
1188 /* Free vmap_area object. */
1189 kmem_cache_free(vmap_area_cachep, va);
1191 /* Point to the new merged area. */
1199 __link_va(va, root, parent, link, head, augment);
1204 static __always_inline struct vmap_area *
1205 merge_or_add_vmap_area(struct vmap_area *va,
1206 struct rb_root *root, struct list_head *head)
1208 return __merge_or_add_vmap_area(va, root, head, false);
1211 static __always_inline struct vmap_area *
1212 merge_or_add_vmap_area_augment(struct vmap_area *va,
1213 struct rb_root *root, struct list_head *head)
1215 va = __merge_or_add_vmap_area(va, root, head, true);
1217 augment_tree_propagate_from(va);
1222 static __always_inline bool
1223 is_within_this_va(struct vmap_area *va, unsigned long size,
1224 unsigned long align, unsigned long vstart)
1226 unsigned long nva_start_addr;
1228 if (va->va_start > vstart)
1229 nva_start_addr = ALIGN(va->va_start, align);
1231 nva_start_addr = ALIGN(vstart, align);
1233 /* Can be overflowed due to big size or alignment. */
1234 if (nva_start_addr + size < nva_start_addr ||
1235 nva_start_addr < vstart)
1238 return (nva_start_addr + size <= va->va_end);
1242 * Find the first free block(lowest start address) in the tree,
1243 * that will accomplish the request corresponding to passing
1244 * parameters. Please note, with an alignment bigger than PAGE_SIZE,
1245 * a search length is adjusted to account for worst case alignment
1248 static __always_inline struct vmap_area *
1249 find_vmap_lowest_match(struct rb_root *root, unsigned long size,
1250 unsigned long align, unsigned long vstart, bool adjust_search_size)
1252 struct vmap_area *va;
1253 struct rb_node *node;
1254 unsigned long length;
1256 /* Start from the root. */
1257 node = root->rb_node;
1259 /* Adjust the search size for alignment overhead. */
1260 length = adjust_search_size ? size + align - 1 : size;
1263 va = rb_entry(node, struct vmap_area, rb_node);
1265 if (get_subtree_max_size(node->rb_left) >= length &&
1266 vstart < va->va_start) {
1267 node = node->rb_left;
1269 if (is_within_this_va(va, size, align, vstart))
1273 * Does not make sense to go deeper towards the right
1274 * sub-tree if it does not have a free block that is
1275 * equal or bigger to the requested search length.
1277 if (get_subtree_max_size(node->rb_right) >= length) {
1278 node = node->rb_right;
1283 * OK. We roll back and find the first right sub-tree,
1284 * that will satisfy the search criteria. It can happen
1285 * due to "vstart" restriction or an alignment overhead
1286 * that is bigger then PAGE_SIZE.
1288 while ((node = rb_parent(node))) {
1289 va = rb_entry(node, struct vmap_area, rb_node);
1290 if (is_within_this_va(va, size, align, vstart))
1293 if (get_subtree_max_size(node->rb_right) >= length &&
1294 vstart <= va->va_start) {
1296 * Shift the vstart forward. Please note, we update it with
1297 * parent's start address adding "1" because we do not want
1298 * to enter same sub-tree after it has already been checked
1299 * and no suitable free block found there.
1301 vstart = va->va_start + 1;
1302 node = node->rb_right;
1312 #if DEBUG_AUGMENT_LOWEST_MATCH_CHECK
1313 #include <linux/random.h>
1315 static struct vmap_area *
1316 find_vmap_lowest_linear_match(struct list_head *head, unsigned long size,
1317 unsigned long align, unsigned long vstart)
1319 struct vmap_area *va;
1321 list_for_each_entry(va, head, list) {
1322 if (!is_within_this_va(va, size, align, vstart))
1332 find_vmap_lowest_match_check(struct rb_root *root, struct list_head *head,
1333 unsigned long size, unsigned long align)
1335 struct vmap_area *va_1, *va_2;
1336 unsigned long vstart;
1339 get_random_bytes(&rnd, sizeof(rnd));
1340 vstart = VMALLOC_START + rnd;
1342 va_1 = find_vmap_lowest_match(root, size, align, vstart, false);
1343 va_2 = find_vmap_lowest_linear_match(head, size, align, vstart);
1346 pr_emerg("not lowest: t: 0x%p, l: 0x%p, v: 0x%lx\n",
1347 va_1, va_2, vstart);
1353 FL_FIT_TYPE = 1, /* full fit */
1354 LE_FIT_TYPE = 2, /* left edge fit */
1355 RE_FIT_TYPE = 3, /* right edge fit */
1356 NE_FIT_TYPE = 4 /* no edge fit */
1359 static __always_inline enum fit_type
1360 classify_va_fit_type(struct vmap_area *va,
1361 unsigned long nva_start_addr, unsigned long size)
1365 /* Check if it is within VA. */
1366 if (nva_start_addr < va->va_start ||
1367 nva_start_addr + size > va->va_end)
1371 if (va->va_start == nva_start_addr) {
1372 if (va->va_end == nva_start_addr + size)
1376 } else if (va->va_end == nva_start_addr + size) {
1385 static __always_inline int
1386 adjust_va_to_fit_type(struct rb_root *root, struct list_head *head,
1387 struct vmap_area *va, unsigned long nva_start_addr,
1390 struct vmap_area *lva = NULL;
1391 enum fit_type type = classify_va_fit_type(va, nva_start_addr, size);
1393 if (type == FL_FIT_TYPE) {
1395 * No need to split VA, it fully fits.
1401 unlink_va_augment(va, root);
1402 kmem_cache_free(vmap_area_cachep, va);
1403 } else if (type == LE_FIT_TYPE) {
1405 * Split left edge of fit VA.
1411 va->va_start += size;
1412 } else if (type == RE_FIT_TYPE) {
1414 * Split right edge of fit VA.
1420 va->va_end = nva_start_addr;
1421 } else if (type == NE_FIT_TYPE) {
1423 * Split no edge of fit VA.
1429 lva = __this_cpu_xchg(ne_fit_preload_node, NULL);
1430 if (unlikely(!lva)) {
1432 * For percpu allocator we do not do any pre-allocation
1433 * and leave it as it is. The reason is it most likely
1434 * never ends up with NE_FIT_TYPE splitting. In case of
1435 * percpu allocations offsets and sizes are aligned to
1436 * fixed align request, i.e. RE_FIT_TYPE and FL_FIT_TYPE
1437 * are its main fitting cases.
1439 * There are a few exceptions though, as an example it is
1440 * a first allocation (early boot up) when we have "one"
1441 * big free space that has to be split.
1443 * Also we can hit this path in case of regular "vmap"
1444 * allocations, if "this" current CPU was not preloaded.
1445 * See the comment in alloc_vmap_area() why. If so, then
1446 * GFP_NOWAIT is used instead to get an extra object for
1447 * split purpose. That is rare and most time does not
1450 * What happens if an allocation gets failed. Basically,
1451 * an "overflow" path is triggered to purge lazily freed
1452 * areas to free some memory, then, the "retry" path is
1453 * triggered to repeat one more time. See more details
1454 * in alloc_vmap_area() function.
1456 lva = kmem_cache_alloc(vmap_area_cachep, GFP_NOWAIT);
1462 * Build the remainder.
1464 lva->va_start = va->va_start;
1465 lva->va_end = nva_start_addr;
1468 * Shrink this VA to remaining size.
1470 va->va_start = nva_start_addr + size;
1475 if (type != FL_FIT_TYPE) {
1476 augment_tree_propagate_from(va);
1478 if (lva) /* type == NE_FIT_TYPE */
1479 insert_vmap_area_augment(lva, &va->rb_node, root, head);
1486 * Returns a start address of the newly allocated area, if success.
1487 * Otherwise a vend is returned that indicates failure.
1489 static __always_inline unsigned long
1490 __alloc_vmap_area(struct rb_root *root, struct list_head *head,
1491 unsigned long size, unsigned long align,
1492 unsigned long vstart, unsigned long vend)
1494 bool adjust_search_size = true;
1495 unsigned long nva_start_addr;
1496 struct vmap_area *va;
1500 * Do not adjust when:
1501 * a) align <= PAGE_SIZE, because it does not make any sense.
1502 * All blocks(their start addresses) are at least PAGE_SIZE
1504 * b) a short range where a requested size corresponds to exactly
1505 * specified [vstart:vend] interval and an alignment > PAGE_SIZE.
1506 * With adjusted search length an allocation would not succeed.
1508 if (align <= PAGE_SIZE || (align > PAGE_SIZE && (vend - vstart) == size))
1509 adjust_search_size = false;
1511 va = find_vmap_lowest_match(root, size, align, vstart, adjust_search_size);
1515 if (va->va_start > vstart)
1516 nva_start_addr = ALIGN(va->va_start, align);
1518 nva_start_addr = ALIGN(vstart, align);
1520 /* Check the "vend" restriction. */
1521 if (nva_start_addr + size > vend)
1524 /* Update the free vmap_area. */
1525 ret = adjust_va_to_fit_type(root, head, va, nva_start_addr, size);
1526 if (WARN_ON_ONCE(ret))
1529 #if DEBUG_AUGMENT_LOWEST_MATCH_CHECK
1530 find_vmap_lowest_match_check(root, head, size, align);
1533 return nva_start_addr;
1537 * Free a region of KVA allocated by alloc_vmap_area
1539 static void free_vmap_area(struct vmap_area *va)
1542 * Remove from the busy tree/list.
1544 spin_lock(&vmap_area_lock);
1545 unlink_va(va, &vmap_area_root);
1546 spin_unlock(&vmap_area_lock);
1549 * Insert/Merge it back to the free tree/list.
1551 spin_lock(&free_vmap_area_lock);
1552 merge_or_add_vmap_area_augment(va, &free_vmap_area_root, &free_vmap_area_list);
1553 spin_unlock(&free_vmap_area_lock);
1557 preload_this_cpu_lock(spinlock_t *lock, gfp_t gfp_mask, int node)
1559 struct vmap_area *va = NULL;
1562 * Preload this CPU with one extra vmap_area object. It is used
1563 * when fit type of free area is NE_FIT_TYPE. It guarantees that
1564 * a CPU that does an allocation is preloaded.
1566 * We do it in non-atomic context, thus it allows us to use more
1567 * permissive allocation masks to be more stable under low memory
1568 * condition and high memory pressure.
1570 if (!this_cpu_read(ne_fit_preload_node))
1571 va = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
1575 if (va && __this_cpu_cmpxchg(ne_fit_preload_node, NULL, va))
1576 kmem_cache_free(vmap_area_cachep, va);
1580 * Allocate a region of KVA of the specified size and alignment, within the
1583 static struct vmap_area *alloc_vmap_area(unsigned long size,
1584 unsigned long align,
1585 unsigned long vstart, unsigned long vend,
1586 int node, gfp_t gfp_mask,
1587 unsigned long va_flags)
1589 struct vmap_area *va;
1590 unsigned long freed;
1595 if (unlikely(!size || offset_in_page(size) || !is_power_of_2(align)))
1596 return ERR_PTR(-EINVAL);
1598 if (unlikely(!vmap_initialized))
1599 return ERR_PTR(-EBUSY);
1602 gfp_mask = gfp_mask & GFP_RECLAIM_MASK;
1604 va = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
1606 return ERR_PTR(-ENOMEM);
1609 * Only scan the relevant parts containing pointers to other objects
1610 * to avoid false negatives.
1612 kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
1615 preload_this_cpu_lock(&free_vmap_area_lock, gfp_mask, node);
1616 addr = __alloc_vmap_area(&free_vmap_area_root, &free_vmap_area_list,
1617 size, align, vstart, vend);
1618 spin_unlock(&free_vmap_area_lock);
1620 trace_alloc_vmap_area(addr, size, align, vstart, vend, addr == vend);
1623 * If an allocation fails, the "vend" address is
1624 * returned. Therefore trigger the overflow path.
1626 if (unlikely(addr == vend))
1629 va->va_start = addr;
1630 va->va_end = addr + size;
1632 va->flags = va_flags;
1634 spin_lock(&vmap_area_lock);
1635 insert_vmap_area(va, &vmap_area_root, &vmap_area_list);
1636 spin_unlock(&vmap_area_lock);
1638 BUG_ON(!IS_ALIGNED(va->va_start, align));
1639 BUG_ON(va->va_start < vstart);
1640 BUG_ON(va->va_end > vend);
1642 ret = kasan_populate_vmalloc(addr, size);
1645 return ERR_PTR(ret);
1652 purge_vmap_area_lazy();
1658 blocking_notifier_call_chain(&vmap_notify_list, 0, &freed);
1665 if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit())
1666 pr_warn("vmap allocation for size %lu failed: use vmalloc=<size> to increase size\n",
1669 kmem_cache_free(vmap_area_cachep, va);
1670 return ERR_PTR(-EBUSY);
1673 int register_vmap_purge_notifier(struct notifier_block *nb)
1675 return blocking_notifier_chain_register(&vmap_notify_list, nb);
1677 EXPORT_SYMBOL_GPL(register_vmap_purge_notifier);
1679 int unregister_vmap_purge_notifier(struct notifier_block *nb)
1681 return blocking_notifier_chain_unregister(&vmap_notify_list, nb);
1683 EXPORT_SYMBOL_GPL(unregister_vmap_purge_notifier);
1686 * lazy_max_pages is the maximum amount of virtual address space we gather up
1687 * before attempting to purge with a TLB flush.
1689 * There is a tradeoff here: a larger number will cover more kernel page tables
1690 * and take slightly longer to purge, but it will linearly reduce the number of
1691 * global TLB flushes that must be performed. It would seem natural to scale
1692 * this number up linearly with the number of CPUs (because vmapping activity
1693 * could also scale linearly with the number of CPUs), however it is likely
1694 * that in practice, workloads might be constrained in other ways that mean
1695 * vmap activity will not scale linearly with CPUs. Also, I want to be
1696 * conservative and not introduce a big latency on huge systems, so go with
1697 * a less aggressive log scale. It will still be an improvement over the old
1698 * code, and it will be simple to change the scale factor if we find that it
1699 * becomes a problem on bigger systems.
1701 static unsigned long lazy_max_pages(void)
1705 log = fls(num_online_cpus());
1707 return log * (32UL * 1024 * 1024 / PAGE_SIZE);
1710 static atomic_long_t vmap_lazy_nr = ATOMIC_LONG_INIT(0);
1713 * Serialize vmap purging. There is no actual critical section protected
1714 * by this lock, but we want to avoid concurrent calls for performance
1715 * reasons and to make the pcpu_get_vm_areas more deterministic.
1717 static DEFINE_MUTEX(vmap_purge_lock);
1719 /* for per-CPU blocks */
1720 static void purge_fragmented_blocks_allcpus(void);
1723 * Purges all lazily-freed vmap areas.
1725 static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end)
1727 unsigned long resched_threshold;
1728 unsigned int num_purged_areas = 0;
1729 struct list_head local_purge_list;
1730 struct vmap_area *va, *n_va;
1732 lockdep_assert_held(&vmap_purge_lock);
1734 spin_lock(&purge_vmap_area_lock);
1735 purge_vmap_area_root = RB_ROOT;
1736 list_replace_init(&purge_vmap_area_list, &local_purge_list);
1737 spin_unlock(&purge_vmap_area_lock);
1739 if (unlikely(list_empty(&local_purge_list)))
1743 list_first_entry(&local_purge_list,
1744 struct vmap_area, list)->va_start);
1747 list_last_entry(&local_purge_list,
1748 struct vmap_area, list)->va_end);
1750 flush_tlb_kernel_range(start, end);
1751 resched_threshold = lazy_max_pages() << 1;
1753 spin_lock(&free_vmap_area_lock);
1754 list_for_each_entry_safe(va, n_va, &local_purge_list, list) {
1755 unsigned long nr = (va->va_end - va->va_start) >> PAGE_SHIFT;
1756 unsigned long orig_start = va->va_start;
1757 unsigned long orig_end = va->va_end;
1760 * Finally insert or merge lazily-freed area. It is
1761 * detached and there is no need to "unlink" it from
1764 va = merge_or_add_vmap_area_augment(va, &free_vmap_area_root,
1765 &free_vmap_area_list);
1770 if (is_vmalloc_or_module_addr((void *)orig_start))
1771 kasan_release_vmalloc(orig_start, orig_end,
1772 va->va_start, va->va_end);
1774 atomic_long_sub(nr, &vmap_lazy_nr);
1777 if (atomic_long_read(&vmap_lazy_nr) < resched_threshold)
1778 cond_resched_lock(&free_vmap_area_lock);
1780 spin_unlock(&free_vmap_area_lock);
1783 trace_purge_vmap_area_lazy(start, end, num_purged_areas);
1784 return num_purged_areas > 0;
1788 * Kick off a purge of the outstanding lazy areas.
1790 static void purge_vmap_area_lazy(void)
1792 mutex_lock(&vmap_purge_lock);
1793 purge_fragmented_blocks_allcpus();
1794 __purge_vmap_area_lazy(ULONG_MAX, 0);
1795 mutex_unlock(&vmap_purge_lock);
1798 static void drain_vmap_area_work(struct work_struct *work)
1800 unsigned long nr_lazy;
1803 mutex_lock(&vmap_purge_lock);
1804 __purge_vmap_area_lazy(ULONG_MAX, 0);
1805 mutex_unlock(&vmap_purge_lock);
1807 /* Recheck if further work is required. */
1808 nr_lazy = atomic_long_read(&vmap_lazy_nr);
1809 } while (nr_lazy > lazy_max_pages());
1813 * Free a vmap area, caller ensuring that the area has been unmapped,
1814 * unlinked and flush_cache_vunmap had been called for the correct
1817 static void free_vmap_area_noflush(struct vmap_area *va)
1819 unsigned long nr_lazy_max = lazy_max_pages();
1820 unsigned long va_start = va->va_start;
1821 unsigned long nr_lazy;
1823 if (WARN_ON_ONCE(!list_empty(&va->list)))
1826 nr_lazy = atomic_long_add_return((va->va_end - va->va_start) >>
1827 PAGE_SHIFT, &vmap_lazy_nr);
1830 * Merge or place it to the purge tree/list.
1832 spin_lock(&purge_vmap_area_lock);
1833 merge_or_add_vmap_area(va,
1834 &purge_vmap_area_root, &purge_vmap_area_list);
1835 spin_unlock(&purge_vmap_area_lock);
1837 trace_free_vmap_area_noflush(va_start, nr_lazy, nr_lazy_max);
1839 /* After this point, we may free va at any time */
1840 if (unlikely(nr_lazy > nr_lazy_max))
1841 schedule_work(&drain_vmap_work);
1845 * Free and unmap a vmap area
1847 static void free_unmap_vmap_area(struct vmap_area *va)
1849 flush_cache_vunmap(va->va_start, va->va_end);
1850 vunmap_range_noflush(va->va_start, va->va_end);
1851 if (debug_pagealloc_enabled_static())
1852 flush_tlb_kernel_range(va->va_start, va->va_end);
1854 free_vmap_area_noflush(va);
1857 struct vmap_area *find_vmap_area(unsigned long addr)
1859 struct vmap_area *va;
1861 spin_lock(&vmap_area_lock);
1862 va = __find_vmap_area(addr, &vmap_area_root);
1863 spin_unlock(&vmap_area_lock);
1868 static struct vmap_area *find_unlink_vmap_area(unsigned long addr)
1870 struct vmap_area *va;
1872 spin_lock(&vmap_area_lock);
1873 va = __find_vmap_area(addr, &vmap_area_root);
1875 unlink_va(va, &vmap_area_root);
1876 spin_unlock(&vmap_area_lock);
1881 /*** Per cpu kva allocator ***/
1884 * vmap space is limited especially on 32 bit architectures. Ensure there is
1885 * room for at least 16 percpu vmap blocks per CPU.
1888 * If we had a constant VMALLOC_START and VMALLOC_END, we'd like to be able
1889 * to #define VMALLOC_SPACE (VMALLOC_END-VMALLOC_START). Guess
1890 * instead (we just need a rough idea)
1892 #if BITS_PER_LONG == 32
1893 #define VMALLOC_SPACE (128UL*1024*1024)
1895 #define VMALLOC_SPACE (128UL*1024*1024*1024)
1898 #define VMALLOC_PAGES (VMALLOC_SPACE / PAGE_SIZE)
1899 #define VMAP_MAX_ALLOC BITS_PER_LONG /* 256K with 4K pages */
1900 #define VMAP_BBMAP_BITS_MAX 1024 /* 4MB with 4K pages */
1901 #define VMAP_BBMAP_BITS_MIN (VMAP_MAX_ALLOC*2)
1902 #define VMAP_MIN(x, y) ((x) < (y) ? (x) : (y)) /* can't use min() */
1903 #define VMAP_MAX(x, y) ((x) > (y) ? (x) : (y)) /* can't use max() */
1904 #define VMAP_BBMAP_BITS \
1905 VMAP_MIN(VMAP_BBMAP_BITS_MAX, \
1906 VMAP_MAX(VMAP_BBMAP_BITS_MIN, \
1907 VMALLOC_PAGES / roundup_pow_of_two(NR_CPUS) / 16))
1909 #define VMAP_BLOCK_SIZE (VMAP_BBMAP_BITS * PAGE_SIZE)
1911 #define VMAP_RAM 0x1 /* indicates vm_map_ram area*/
1912 #define VMAP_BLOCK 0x2 /* mark out the vmap_block sub-type*/
1913 #define VMAP_FLAGS_MASK 0x3
1915 struct vmap_block_queue {
1917 struct list_head free;
1920 * An xarray requires an extra memory dynamically to
1921 * be allocated. If it is an issue, we can use rb-tree
1924 struct xarray vmap_blocks;
1929 struct vmap_area *va;
1930 unsigned long free, dirty;
1931 DECLARE_BITMAP(used_map, VMAP_BBMAP_BITS);
1932 unsigned long dirty_min, dirty_max; /*< dirty range */
1933 struct list_head free_list;
1934 struct rcu_head rcu_head;
1935 struct list_head purge;
1938 /* Queue of free and dirty vmap blocks, for allocation and flushing purposes */
1939 static DEFINE_PER_CPU(struct vmap_block_queue, vmap_block_queue);
1942 * In order to fast access to any "vmap_block" associated with a
1943 * specific address, we use a hash.
1945 * A per-cpu vmap_block_queue is used in both ways, to serialize
1946 * an access to free block chains among CPUs(alloc path) and it
1947 * also acts as a vmap_block hash(alloc/free paths). It means we
1948 * overload it, since we already have the per-cpu array which is
1949 * used as a hash table. When used as a hash a 'cpu' passed to
1950 * per_cpu() is not actually a CPU but rather a hash index.
1952 * A hash function is addr_to_vb_xa() which hashes any address
1953 * to a specific index(in a hash) it belongs to. This then uses a
1954 * per_cpu() macro to access an array with generated index.
1961 * 0 10 20 30 40 50 60
1962 * |------|------|------|------|------|------|...<vmap address space>
1963 * CPU0 CPU1 CPU2 CPU0 CPU1 CPU2
1965 * - CPU_1 invokes vm_unmap_ram(6), 6 belongs to CPU0 zone, thus
1966 * it access: CPU0/INDEX0 -> vmap_blocks -> xa_lock;
1968 * - CPU_2 invokes vm_unmap_ram(11), 11 belongs to CPU1 zone, thus
1969 * it access: CPU1/INDEX1 -> vmap_blocks -> xa_lock;
1971 * - CPU_0 invokes vm_unmap_ram(20), 20 belongs to CPU2 zone, thus
1972 * it access: CPU2/INDEX2 -> vmap_blocks -> xa_lock.
1974 * This technique almost always avoids lock contention on insert/remove,
1975 * however xarray spinlocks protect against any contention that remains.
1977 static struct xarray *
1978 addr_to_vb_xa(unsigned long addr)
1980 int index = (addr / VMAP_BLOCK_SIZE) % num_possible_cpus();
1982 return &per_cpu(vmap_block_queue, index).vmap_blocks;
1986 * We should probably have a fallback mechanism to allocate virtual memory
1987 * out of partially filled vmap blocks. However vmap block sizing should be
1988 * fairly reasonable according to the vmalloc size, so it shouldn't be a
1992 static unsigned long addr_to_vb_idx(unsigned long addr)
1994 addr -= VMALLOC_START & ~(VMAP_BLOCK_SIZE-1);
1995 addr /= VMAP_BLOCK_SIZE;
1999 static void *vmap_block_vaddr(unsigned long va_start, unsigned long pages_off)
2003 addr = va_start + (pages_off << PAGE_SHIFT);
2004 BUG_ON(addr_to_vb_idx(addr) != addr_to_vb_idx(va_start));
2005 return (void *)addr;
2009 * new_vmap_block - allocates new vmap_block and occupies 2^order pages in this
2010 * block. Of course pages number can't exceed VMAP_BBMAP_BITS
2011 * @order: how many 2^order pages should be occupied in newly allocated block
2012 * @gfp_mask: flags for the page level allocator
2014 * Return: virtual address in a newly allocated block or ERR_PTR(-errno)
2016 static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
2018 struct vmap_block_queue *vbq;
2019 struct vmap_block *vb;
2020 struct vmap_area *va;
2022 unsigned long vb_idx;
2026 node = numa_node_id();
2028 vb = kmalloc_node(sizeof(struct vmap_block),
2029 gfp_mask & GFP_RECLAIM_MASK, node);
2031 return ERR_PTR(-ENOMEM);
2033 va = alloc_vmap_area(VMAP_BLOCK_SIZE, VMAP_BLOCK_SIZE,
2034 VMALLOC_START, VMALLOC_END,
2036 VMAP_RAM|VMAP_BLOCK);
2039 return ERR_CAST(va);
2042 vaddr = vmap_block_vaddr(va->va_start, 0);
2043 spin_lock_init(&vb->lock);
2045 /* At least something should be left free */
2046 BUG_ON(VMAP_BBMAP_BITS <= (1UL << order));
2047 bitmap_zero(vb->used_map, VMAP_BBMAP_BITS);
2048 vb->free = VMAP_BBMAP_BITS - (1UL << order);
2050 vb->dirty_min = VMAP_BBMAP_BITS;
2052 bitmap_set(vb->used_map, 0, (1UL << order));
2053 INIT_LIST_HEAD(&vb->free_list);
2055 xa = addr_to_vb_xa(va->va_start);
2056 vb_idx = addr_to_vb_idx(va->va_start);
2057 err = xa_insert(xa, vb_idx, vb, gfp_mask);
2061 return ERR_PTR(err);
2064 vbq = raw_cpu_ptr(&vmap_block_queue);
2065 spin_lock(&vbq->lock);
2066 list_add_tail_rcu(&vb->free_list, &vbq->free);
2067 spin_unlock(&vbq->lock);
2072 static void free_vmap_block(struct vmap_block *vb)
2074 struct vmap_block *tmp;
2077 xa = addr_to_vb_xa(vb->va->va_start);
2078 tmp = xa_erase(xa, addr_to_vb_idx(vb->va->va_start));
2081 spin_lock(&vmap_area_lock);
2082 unlink_va(vb->va, &vmap_area_root);
2083 spin_unlock(&vmap_area_lock);
2085 free_vmap_area_noflush(vb->va);
2086 kfree_rcu(vb, rcu_head);
2089 static void purge_fragmented_blocks(int cpu)
2092 struct vmap_block *vb;
2093 struct vmap_block *n_vb;
2094 struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
2097 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
2099 if (!(vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS))
2102 spin_lock(&vb->lock);
2103 if (vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS) {
2104 vb->free = 0; /* prevent further allocs after releasing lock */
2105 vb->dirty = VMAP_BBMAP_BITS; /* prevent purging it again */
2107 vb->dirty_max = VMAP_BBMAP_BITS;
2108 spin_lock(&vbq->lock);
2109 list_del_rcu(&vb->free_list);
2110 spin_unlock(&vbq->lock);
2111 spin_unlock(&vb->lock);
2112 list_add_tail(&vb->purge, &purge);
2114 spin_unlock(&vb->lock);
2118 list_for_each_entry_safe(vb, n_vb, &purge, purge) {
2119 list_del(&vb->purge);
2120 free_vmap_block(vb);
2124 static void purge_fragmented_blocks_allcpus(void)
2128 for_each_possible_cpu(cpu)
2129 purge_fragmented_blocks(cpu);
2132 static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
2134 struct vmap_block_queue *vbq;
2135 struct vmap_block *vb;
2139 BUG_ON(offset_in_page(size));
2140 BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
2141 if (WARN_ON(size == 0)) {
2143 * Allocating 0 bytes isn't what caller wants since
2144 * get_order(0) returns funny result. Just warn and terminate
2149 order = get_order(size);
2152 vbq = raw_cpu_ptr(&vmap_block_queue);
2153 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
2154 unsigned long pages_off;
2156 spin_lock(&vb->lock);
2157 if (vb->free < (1UL << order)) {
2158 spin_unlock(&vb->lock);
2162 pages_off = VMAP_BBMAP_BITS - vb->free;
2163 vaddr = vmap_block_vaddr(vb->va->va_start, pages_off);
2164 vb->free -= 1UL << order;
2165 bitmap_set(vb->used_map, pages_off, (1UL << order));
2166 if (vb->free == 0) {
2167 spin_lock(&vbq->lock);
2168 list_del_rcu(&vb->free_list);
2169 spin_unlock(&vbq->lock);
2172 spin_unlock(&vb->lock);
2178 /* Allocate new block if nothing was found */
2180 vaddr = new_vmap_block(order, gfp_mask);
2185 static void vb_free(unsigned long addr, unsigned long size)
2187 unsigned long offset;
2189 struct vmap_block *vb;
2192 BUG_ON(offset_in_page(size));
2193 BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
2195 flush_cache_vunmap(addr, addr + size);
2197 order = get_order(size);
2198 offset = (addr & (VMAP_BLOCK_SIZE - 1)) >> PAGE_SHIFT;
2200 xa = addr_to_vb_xa(addr);
2201 vb = xa_load(xa, addr_to_vb_idx(addr));
2203 spin_lock(&vb->lock);
2204 bitmap_clear(vb->used_map, offset, (1UL << order));
2205 spin_unlock(&vb->lock);
2207 vunmap_range_noflush(addr, addr + size);
2209 if (debug_pagealloc_enabled_static())
2210 flush_tlb_kernel_range(addr, addr + size);
2212 spin_lock(&vb->lock);
2214 /* Expand dirty range */
2215 vb->dirty_min = min(vb->dirty_min, offset);
2216 vb->dirty_max = max(vb->dirty_max, offset + (1UL << order));
2218 vb->dirty += 1UL << order;
2219 if (vb->dirty == VMAP_BBMAP_BITS) {
2221 spin_unlock(&vb->lock);
2222 free_vmap_block(vb);
2224 spin_unlock(&vb->lock);
2227 static void _vm_unmap_aliases(unsigned long start, unsigned long end, int flush)
2231 if (unlikely(!vmap_initialized))
2236 for_each_possible_cpu(cpu) {
2237 struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
2238 struct vmap_block *vb;
2241 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
2242 spin_lock(&vb->lock);
2243 if (vb->dirty && vb->dirty != VMAP_BBMAP_BITS) {
2244 unsigned long va_start = vb->va->va_start;
2247 s = va_start + (vb->dirty_min << PAGE_SHIFT);
2248 e = va_start + (vb->dirty_max << PAGE_SHIFT);
2250 start = min(s, start);
2255 spin_unlock(&vb->lock);
2260 mutex_lock(&vmap_purge_lock);
2261 purge_fragmented_blocks_allcpus();
2262 if (!__purge_vmap_area_lazy(start, end) && flush)
2263 flush_tlb_kernel_range(start, end);
2264 mutex_unlock(&vmap_purge_lock);
2268 * vm_unmap_aliases - unmap outstanding lazy aliases in the vmap layer
2270 * The vmap/vmalloc layer lazily flushes kernel virtual mappings primarily
2271 * to amortize TLB flushing overheads. What this means is that any page you
2272 * have now, may, in a former life, have been mapped into kernel virtual
2273 * address by the vmap layer and so there might be some CPUs with TLB entries
2274 * still referencing that page (additional to the regular 1:1 kernel mapping).
2276 * vm_unmap_aliases flushes all such lazy mappings. After it returns, we can
2277 * be sure that none of the pages we have control over will have any aliases
2278 * from the vmap layer.
2280 void vm_unmap_aliases(void)
2282 unsigned long start = ULONG_MAX, end = 0;
2285 _vm_unmap_aliases(start, end, flush);
2287 EXPORT_SYMBOL_GPL(vm_unmap_aliases);
2290 * vm_unmap_ram - unmap linear kernel address space set up by vm_map_ram
2291 * @mem: the pointer returned by vm_map_ram
2292 * @count: the count passed to that vm_map_ram call (cannot unmap partial)
2294 void vm_unmap_ram(const void *mem, unsigned int count)
2296 unsigned long size = (unsigned long)count << PAGE_SHIFT;
2297 unsigned long addr = (unsigned long)kasan_reset_tag(mem);
2298 struct vmap_area *va;
2302 BUG_ON(addr < VMALLOC_START);
2303 BUG_ON(addr > VMALLOC_END);
2304 BUG_ON(!PAGE_ALIGNED(addr));
2306 kasan_poison_vmalloc(mem, size);
2308 if (likely(count <= VMAP_MAX_ALLOC)) {
2309 debug_check_no_locks_freed(mem, size);
2310 vb_free(addr, size);
2314 va = find_unlink_vmap_area(addr);
2315 if (WARN_ON_ONCE(!va))
2318 debug_check_no_locks_freed((void *)va->va_start,
2319 (va->va_end - va->va_start));
2320 free_unmap_vmap_area(va);
2322 EXPORT_SYMBOL(vm_unmap_ram);
2325 * vm_map_ram - map pages linearly into kernel virtual address (vmalloc space)
2326 * @pages: an array of pointers to the pages to be mapped
2327 * @count: number of pages
2328 * @node: prefer to allocate data structures on this node
2330 * If you use this function for less than VMAP_MAX_ALLOC pages, it could be
2331 * faster than vmap so it's good. But if you mix long-life and short-life
2332 * objects with vm_map_ram(), it could consume lots of address space through
2333 * fragmentation (especially on a 32bit machine). You could see failures in
2334 * the end. Please use this function for short-lived objects.
2336 * Returns: a pointer to the address that has been mapped, or %NULL on failure
2338 void *vm_map_ram(struct page **pages, unsigned int count, int node)
2340 unsigned long size = (unsigned long)count << PAGE_SHIFT;
2344 if (likely(count <= VMAP_MAX_ALLOC)) {
2345 mem = vb_alloc(size, GFP_KERNEL);
2348 addr = (unsigned long)mem;
2350 struct vmap_area *va;
2351 va = alloc_vmap_area(size, PAGE_SIZE,
2352 VMALLOC_START, VMALLOC_END,
2353 node, GFP_KERNEL, VMAP_RAM);
2357 addr = va->va_start;
2361 if (vmap_pages_range(addr, addr + size, PAGE_KERNEL,
2362 pages, PAGE_SHIFT) < 0) {
2363 vm_unmap_ram(mem, count);
2368 * Mark the pages as accessible, now that they are mapped.
2369 * With hardware tag-based KASAN, marking is skipped for
2370 * non-VM_ALLOC mappings, see __kasan_unpoison_vmalloc().
2372 mem = kasan_unpoison_vmalloc(mem, size, KASAN_VMALLOC_PROT_NORMAL);
2376 EXPORT_SYMBOL(vm_map_ram);
2378 static struct vm_struct *vmlist __initdata;
2380 static inline unsigned int vm_area_page_order(struct vm_struct *vm)
2382 #ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
2383 return vm->page_order;
2389 static inline void set_vm_area_page_order(struct vm_struct *vm, unsigned int order)
2391 #ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
2392 vm->page_order = order;
2399 * vm_area_add_early - add vmap area early during boot
2400 * @vm: vm_struct to add
2402 * This function is used to add fixed kernel vm area to vmlist before
2403 * vmalloc_init() is called. @vm->addr, @vm->size, and @vm->flags
2404 * should contain proper values and the other fields should be zero.
2406 * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
2408 void __init vm_area_add_early(struct vm_struct *vm)
2410 struct vm_struct *tmp, **p;
2412 BUG_ON(vmap_initialized);
2413 for (p = &vmlist; (tmp = *p) != NULL; p = &tmp->next) {
2414 if (tmp->addr >= vm->addr) {
2415 BUG_ON(tmp->addr < vm->addr + vm->size);
2418 BUG_ON(tmp->addr + tmp->size > vm->addr);
2425 * vm_area_register_early - register vmap area early during boot
2426 * @vm: vm_struct to register
2427 * @align: requested alignment
2429 * This function is used to register kernel vm area before
2430 * vmalloc_init() is called. @vm->size and @vm->flags should contain
2431 * proper values on entry and other fields should be zero. On return,
2432 * vm->addr contains the allocated address.
2434 * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
2436 void __init vm_area_register_early(struct vm_struct *vm, size_t align)
2438 unsigned long addr = ALIGN(VMALLOC_START, align);
2439 struct vm_struct *cur, **p;
2441 BUG_ON(vmap_initialized);
2443 for (p = &vmlist; (cur = *p) != NULL; p = &cur->next) {
2444 if ((unsigned long)cur->addr - addr >= vm->size)
2446 addr = ALIGN((unsigned long)cur->addr + cur->size, align);
2449 BUG_ON(addr > VMALLOC_END - vm->size);
2450 vm->addr = (void *)addr;
2453 kasan_populate_early_vm_area_shadow(vm->addr, vm->size);
2456 static void vmap_init_free_space(void)
2458 unsigned long vmap_start = 1;
2459 const unsigned long vmap_end = ULONG_MAX;
2460 struct vmap_area *busy, *free;
2464 * -|-----|.....|-----|-----|-----|.....|-
2466 * |<--------------------------------->|
2468 list_for_each_entry(busy, &vmap_area_list, list) {
2469 if (busy->va_start - vmap_start > 0) {
2470 free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
2471 if (!WARN_ON_ONCE(!free)) {
2472 free->va_start = vmap_start;
2473 free->va_end = busy->va_start;
2475 insert_vmap_area_augment(free, NULL,
2476 &free_vmap_area_root,
2477 &free_vmap_area_list);
2481 vmap_start = busy->va_end;
2484 if (vmap_end - vmap_start > 0) {
2485 free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
2486 if (!WARN_ON_ONCE(!free)) {
2487 free->va_start = vmap_start;
2488 free->va_end = vmap_end;
2490 insert_vmap_area_augment(free, NULL,
2491 &free_vmap_area_root,
2492 &free_vmap_area_list);
2497 static inline void setup_vmalloc_vm_locked(struct vm_struct *vm,
2498 struct vmap_area *va, unsigned long flags, const void *caller)
2501 vm->addr = (void *)va->va_start;
2502 vm->size = va->va_end - va->va_start;
2503 vm->caller = caller;
2507 static void setup_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va,
2508 unsigned long flags, const void *caller)
2510 spin_lock(&vmap_area_lock);
2511 setup_vmalloc_vm_locked(vm, va, flags, caller);
2512 spin_unlock(&vmap_area_lock);
2515 static void clear_vm_uninitialized_flag(struct vm_struct *vm)
2518 * Before removing VM_UNINITIALIZED,
2519 * we should make sure that vm has proper values.
2520 * Pair with smp_rmb() in show_numa_info().
2523 vm->flags &= ~VM_UNINITIALIZED;
2526 static struct vm_struct *__get_vm_area_node(unsigned long size,
2527 unsigned long align, unsigned long shift, unsigned long flags,
2528 unsigned long start, unsigned long end, int node,
2529 gfp_t gfp_mask, const void *caller)
2531 struct vmap_area *va;
2532 struct vm_struct *area;
2533 unsigned long requested_size = size;
2535 BUG_ON(in_interrupt());
2536 size = ALIGN(size, 1ul << shift);
2537 if (unlikely(!size))
2540 if (flags & VM_IOREMAP)
2541 align = 1ul << clamp_t(int, get_count_order_long(size),
2542 PAGE_SHIFT, IOREMAP_MAX_ORDER);
2544 area = kzalloc_node(sizeof(*area), gfp_mask & GFP_RECLAIM_MASK, node);
2545 if (unlikely(!area))
2548 if (!(flags & VM_NO_GUARD))
2551 va = alloc_vmap_area(size, align, start, end, node, gfp_mask, 0);
2557 setup_vmalloc_vm(area, va, flags, caller);
2560 * Mark pages for non-VM_ALLOC mappings as accessible. Do it now as a
2561 * best-effort approach, as they can be mapped outside of vmalloc code.
2562 * For VM_ALLOC mappings, the pages are marked as accessible after
2563 * getting mapped in __vmalloc_node_range().
2564 * With hardware tag-based KASAN, marking is skipped for
2565 * non-VM_ALLOC mappings, see __kasan_unpoison_vmalloc().
2567 if (!(flags & VM_ALLOC))
2568 area->addr = kasan_unpoison_vmalloc(area->addr, requested_size,
2569 KASAN_VMALLOC_PROT_NORMAL);
2574 struct vm_struct *__get_vm_area_caller(unsigned long size, unsigned long flags,
2575 unsigned long start, unsigned long end,
2578 return __get_vm_area_node(size, 1, PAGE_SHIFT, flags, start, end,
2579 NUMA_NO_NODE, GFP_KERNEL, caller);
2583 * get_vm_area - reserve a contiguous kernel virtual area
2584 * @size: size of the area
2585 * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC
2587 * Search an area of @size in the kernel virtual mapping area,
2588 * and reserved it for out purposes. Returns the area descriptor
2589 * on success or %NULL on failure.
2591 * Return: the area descriptor on success or %NULL on failure.
2593 struct vm_struct *get_vm_area(unsigned long size, unsigned long flags)
2595 return __get_vm_area_node(size, 1, PAGE_SHIFT, flags,
2596 VMALLOC_START, VMALLOC_END,
2597 NUMA_NO_NODE, GFP_KERNEL,
2598 __builtin_return_address(0));
2601 struct vm_struct *get_vm_area_caller(unsigned long size, unsigned long flags,
2604 return __get_vm_area_node(size, 1, PAGE_SHIFT, flags,
2605 VMALLOC_START, VMALLOC_END,
2606 NUMA_NO_NODE, GFP_KERNEL, caller);
2610 * find_vm_area - find a continuous kernel virtual area
2611 * @addr: base address
2613 * Search for the kernel VM area starting at @addr, and return it.
2614 * It is up to the caller to do all required locking to keep the returned
2617 * Return: the area descriptor on success or %NULL on failure.
2619 struct vm_struct *find_vm_area(const void *addr)
2621 struct vmap_area *va;
2623 va = find_vmap_area((unsigned long)addr);
2631 * remove_vm_area - find and remove a continuous kernel virtual area
2632 * @addr: base address
2634 * Search for the kernel VM area starting at @addr, and remove it.
2635 * This function returns the found VM area, but using it is NOT safe
2636 * on SMP machines, except for its size or flags.
2638 * Return: the area descriptor on success or %NULL on failure.
2640 struct vm_struct *remove_vm_area(const void *addr)
2642 struct vmap_area *va;
2643 struct vm_struct *vm;
2647 if (WARN(!PAGE_ALIGNED(addr), "Trying to vfree() bad address (%p)\n",
2651 va = find_unlink_vmap_area((unsigned long)addr);
2656 debug_check_no_locks_freed(vm->addr, get_vm_area_size(vm));
2657 debug_check_no_obj_freed(vm->addr, get_vm_area_size(vm));
2658 kasan_free_module_shadow(vm);
2659 kasan_poison_vmalloc(vm->addr, get_vm_area_size(vm));
2661 free_unmap_vmap_area(va);
2665 static inline void set_area_direct_map(const struct vm_struct *area,
2666 int (*set_direct_map)(struct page *page))
2670 /* HUGE_VMALLOC passes small pages to set_direct_map */
2671 for (i = 0; i < area->nr_pages; i++)
2672 if (page_address(area->pages[i]))
2673 set_direct_map(area->pages[i]);
2677 * Flush the vm mapping and reset the direct map.
2679 static void vm_reset_perms(struct vm_struct *area)
2681 unsigned long start = ULONG_MAX, end = 0;
2682 unsigned int page_order = vm_area_page_order(area);
2687 * Find the start and end range of the direct mappings to make sure that
2688 * the vm_unmap_aliases() flush includes the direct map.
2690 for (i = 0; i < area->nr_pages; i += 1U << page_order) {
2691 unsigned long addr = (unsigned long)page_address(area->pages[i]);
2694 unsigned long page_size;
2696 page_size = PAGE_SIZE << page_order;
2697 start = min(addr, start);
2698 end = max(addr + page_size, end);
2704 * Set direct map to something invalid so that it won't be cached if
2705 * there are any accesses after the TLB flush, then flush the TLB and
2706 * reset the direct map permissions to the default.
2708 set_area_direct_map(area, set_direct_map_invalid_noflush);
2709 _vm_unmap_aliases(start, end, flush_dmap);
2710 set_area_direct_map(area, set_direct_map_default_noflush);
2713 static void delayed_vfree_work(struct work_struct *w)
2715 struct vfree_deferred *p = container_of(w, struct vfree_deferred, wq);
2716 struct llist_node *t, *llnode;
2718 llist_for_each_safe(llnode, t, llist_del_all(&p->list))
2723 * vfree_atomic - release memory allocated by vmalloc()
2724 * @addr: memory base address
2726 * This one is just like vfree() but can be called in any atomic context
2729 void vfree_atomic(const void *addr)
2731 struct vfree_deferred *p = raw_cpu_ptr(&vfree_deferred);
2734 kmemleak_free(addr);
2737 * Use raw_cpu_ptr() because this can be called from preemptible
2738 * context. Preemption is absolutely fine here, because the llist_add()
2739 * implementation is lockless, so it works even if we are adding to
2740 * another cpu's list. schedule_work() should be fine with this too.
2742 if (addr && llist_add((struct llist_node *)addr, &p->list))
2743 schedule_work(&p->wq);
2747 * vfree - Release memory allocated by vmalloc()
2748 * @addr: Memory base address
2750 * Free the virtually continuous memory area starting at @addr, as obtained
2751 * from one of the vmalloc() family of APIs. This will usually also free the
2752 * physical memory underlying the virtual allocation, but that memory is
2753 * reference counted, so it will not be freed until the last user goes away.
2755 * If @addr is NULL, no operation is performed.
2758 * May sleep if called *not* from interrupt context.
2759 * Must not be called in NMI context (strictly speaking, it could be
2760 * if we have CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG, but making the calling
2761 * conventions for vfree() arch-dependent would be a really bad idea).
2763 void vfree(const void *addr)
2765 struct vm_struct *vm;
2768 if (unlikely(in_interrupt())) {
2774 kmemleak_free(addr);
2780 vm = remove_vm_area(addr);
2781 if (unlikely(!vm)) {
2782 WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n",
2787 if (unlikely(vm->flags & VM_FLUSH_RESET_PERMS))
2789 for (i = 0; i < vm->nr_pages; i++) {
2790 struct page *page = vm->pages[i];
2793 mod_memcg_page_state(page, MEMCG_VMALLOC, -1);
2795 * High-order allocs for huge vmallocs are split, so
2796 * can be freed as an array of order-0 allocations
2801 atomic_long_sub(vm->nr_pages, &nr_vmalloc_pages);
2805 EXPORT_SYMBOL(vfree);
2808 * vunmap - release virtual mapping obtained by vmap()
2809 * @addr: memory base address
2811 * Free the virtually contiguous memory area starting at @addr,
2812 * which was created from the page array passed to vmap().
2814 * Must not be called in interrupt context.
2816 void vunmap(const void *addr)
2818 struct vm_struct *vm;
2820 BUG_ON(in_interrupt());
2825 vm = remove_vm_area(addr);
2826 if (unlikely(!vm)) {
2827 WARN(1, KERN_ERR "Trying to vunmap() nonexistent vm area (%p)\n",
2833 EXPORT_SYMBOL(vunmap);
2836 * vmap - map an array of pages into virtually contiguous space
2837 * @pages: array of page pointers
2838 * @count: number of pages to map
2839 * @flags: vm_area->flags
2840 * @prot: page protection for the mapping
2842 * Maps @count pages from @pages into contiguous kernel virtual space.
2843 * If @flags contains %VM_MAP_PUT_PAGES the ownership of the pages array itself
2844 * (which must be kmalloc or vmalloc memory) and one reference per pages in it
2845 * are transferred from the caller to vmap(), and will be freed / dropped when
2846 * vfree() is called on the return value.
2848 * Return: the address of the area or %NULL on failure
2850 void *vmap(struct page **pages, unsigned int count,
2851 unsigned long flags, pgprot_t prot)
2853 struct vm_struct *area;
2855 unsigned long size; /* In bytes */
2859 if (WARN_ON_ONCE(flags & VM_FLUSH_RESET_PERMS))
2863 * Your top guard is someone else's bottom guard. Not having a top
2864 * guard compromises someone else's mappings too.
2866 if (WARN_ON_ONCE(flags & VM_NO_GUARD))
2867 flags &= ~VM_NO_GUARD;
2869 if (count > totalram_pages())
2872 size = (unsigned long)count << PAGE_SHIFT;
2873 area = get_vm_area_caller(size, flags, __builtin_return_address(0));
2877 addr = (unsigned long)area->addr;
2878 if (vmap_pages_range(addr, addr + size, pgprot_nx(prot),
2879 pages, PAGE_SHIFT) < 0) {
2884 if (flags & VM_MAP_PUT_PAGES) {
2885 area->pages = pages;
2886 area->nr_pages = count;
2890 EXPORT_SYMBOL(vmap);
2892 #ifdef CONFIG_VMAP_PFN
2893 struct vmap_pfn_data {
2894 unsigned long *pfns;
2899 static int vmap_pfn_apply(pte_t *pte, unsigned long addr, void *private)
2901 struct vmap_pfn_data *data = private;
2903 if (WARN_ON_ONCE(pfn_valid(data->pfns[data->idx])))
2905 *pte = pte_mkspecial(pfn_pte(data->pfns[data->idx++], data->prot));
2910 * vmap_pfn - map an array of PFNs into virtually contiguous space
2911 * @pfns: array of PFNs
2912 * @count: number of pages to map
2913 * @prot: page protection for the mapping
2915 * Maps @count PFNs from @pfns into contiguous kernel virtual space and returns
2916 * the start address of the mapping.
2918 void *vmap_pfn(unsigned long *pfns, unsigned int count, pgprot_t prot)
2920 struct vmap_pfn_data data = { .pfns = pfns, .prot = pgprot_nx(prot) };
2921 struct vm_struct *area;
2923 area = get_vm_area_caller(count * PAGE_SIZE, VM_IOREMAP,
2924 __builtin_return_address(0));
2927 if (apply_to_page_range(&init_mm, (unsigned long)area->addr,
2928 count * PAGE_SIZE, vmap_pfn_apply, &data)) {
2933 flush_cache_vmap((unsigned long)area->addr,
2934 (unsigned long)area->addr + count * PAGE_SIZE);
2938 EXPORT_SYMBOL_GPL(vmap_pfn);
2939 #endif /* CONFIG_VMAP_PFN */
2941 static inline unsigned int
2942 vm_area_alloc_pages(gfp_t gfp, int nid,
2943 unsigned int order, unsigned int nr_pages, struct page **pages)
2945 unsigned int nr_allocated = 0;
2946 gfp_t alloc_gfp = gfp;
2947 bool nofail = false;
2952 * For order-0 pages we make use of bulk allocator, if
2953 * the page array is partly or not at all populated due
2954 * to fails, fallback to a single page allocator that is
2958 /* bulk allocator doesn't support nofail req. officially */
2959 gfp_t bulk_gfp = gfp & ~__GFP_NOFAIL;
2961 while (nr_allocated < nr_pages) {
2962 unsigned int nr, nr_pages_request;
2965 * A maximum allowed request is hard-coded and is 100
2966 * pages per call. That is done in order to prevent a
2967 * long preemption off scenario in the bulk-allocator
2968 * so the range is [1:100].
2970 nr_pages_request = min(100U, nr_pages - nr_allocated);
2972 /* memory allocation should consider mempolicy, we can't
2973 * wrongly use nearest node when nid == NUMA_NO_NODE,
2974 * otherwise memory may be allocated in only one node,
2975 * but mempolicy wants to alloc memory by interleaving.
2977 if (IS_ENABLED(CONFIG_NUMA) && nid == NUMA_NO_NODE)
2978 nr = alloc_pages_bulk_array_mempolicy(bulk_gfp,
2980 pages + nr_allocated);
2983 nr = alloc_pages_bulk_array_node(bulk_gfp, nid,
2985 pages + nr_allocated);
2991 * If zero or pages were obtained partly,
2992 * fallback to a single page allocator.
2994 if (nr != nr_pages_request)
2997 } else if (gfp & __GFP_NOFAIL) {
2999 * Higher order nofail allocations are really expensive and
3000 * potentially dangerous (pre-mature OOM, disruptive reclaim
3001 * and compaction etc.
3003 alloc_gfp &= ~__GFP_NOFAIL;
3007 /* High-order pages or fallback path if "bulk" fails. */
3008 while (nr_allocated < nr_pages) {
3009 if (fatal_signal_pending(current))
3012 if (nid == NUMA_NO_NODE)
3013 page = alloc_pages(alloc_gfp, order);
3015 page = alloc_pages_node(nid, alloc_gfp, order);
3016 if (unlikely(!page)) {
3020 /* fall back to the zero order allocations */
3021 alloc_gfp |= __GFP_NOFAIL;
3027 * Higher order allocations must be able to be treated as
3028 * indepdenent small pages by callers (as they can with
3029 * small-page vmallocs). Some drivers do their own refcounting
3030 * on vmalloc_to_page() pages, some use page->mapping,
3034 split_page(page, order);
3037 * Careful, we allocate and map page-order pages, but
3038 * tracking is done per PAGE_SIZE page so as to keep the
3039 * vm_struct APIs independent of the physical/mapped size.
3041 for (i = 0; i < (1U << order); i++)
3042 pages[nr_allocated + i] = page + i;
3045 nr_allocated += 1U << order;
3048 return nr_allocated;
3051 static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
3052 pgprot_t prot, unsigned int page_shift,
3055 const gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO;
3056 bool nofail = gfp_mask & __GFP_NOFAIL;
3057 unsigned long addr = (unsigned long)area->addr;
3058 unsigned long size = get_vm_area_size(area);
3059 unsigned long array_size;
3060 unsigned int nr_small_pages = size >> PAGE_SHIFT;
3061 unsigned int page_order;
3065 array_size = (unsigned long)nr_small_pages * sizeof(struct page *);
3067 if (!(gfp_mask & (GFP_DMA | GFP_DMA32)))
3068 gfp_mask |= __GFP_HIGHMEM;
3070 /* Please note that the recursion is strictly bounded. */
3071 if (array_size > PAGE_SIZE) {
3072 area->pages = __vmalloc_node(array_size, 1, nested_gfp, node,
3075 area->pages = kmalloc_node(array_size, nested_gfp, node);
3079 warn_alloc(gfp_mask, NULL,
3080 "vmalloc error: size %lu, failed to allocated page array size %lu",
3081 nr_small_pages * PAGE_SIZE, array_size);
3086 set_vm_area_page_order(area, page_shift - PAGE_SHIFT);
3087 page_order = vm_area_page_order(area);
3089 area->nr_pages = vm_area_alloc_pages(gfp_mask | __GFP_NOWARN,
3090 node, page_order, nr_small_pages, area->pages);
3092 atomic_long_add(area->nr_pages, &nr_vmalloc_pages);
3093 if (gfp_mask & __GFP_ACCOUNT) {
3096 for (i = 0; i < area->nr_pages; i++)
3097 mod_memcg_page_state(area->pages[i], MEMCG_VMALLOC, 1);
3101 * If not enough pages were obtained to accomplish an
3102 * allocation request, free them via vfree() if any.
3104 if (area->nr_pages != nr_small_pages) {
3106 * vm_area_alloc_pages() can fail due to insufficient memory but
3109 * - a pending fatal signal
3110 * - insufficient huge page-order pages
3112 * Since we always retry allocations at order-0 in the huge page
3113 * case a warning for either is spurious.
3115 if (!fatal_signal_pending(current) && page_order == 0)
3116 warn_alloc(gfp_mask, NULL,
3117 "vmalloc error: size %lu, failed to allocate pages",
3118 area->nr_pages * PAGE_SIZE);
3123 * page tables allocations ignore external gfp mask, enforce it
3126 if ((gfp_mask & (__GFP_FS | __GFP_IO)) == __GFP_IO)
3127 flags = memalloc_nofs_save();
3128 else if ((gfp_mask & (__GFP_FS | __GFP_IO)) == 0)
3129 flags = memalloc_noio_save();
3132 ret = vmap_pages_range(addr, addr + size, prot, area->pages,
3134 if (nofail && (ret < 0))
3135 schedule_timeout_uninterruptible(1);
3136 } while (nofail && (ret < 0));
3138 if ((gfp_mask & (__GFP_FS | __GFP_IO)) == __GFP_IO)
3139 memalloc_nofs_restore(flags);
3140 else if ((gfp_mask & (__GFP_FS | __GFP_IO)) == 0)
3141 memalloc_noio_restore(flags);
3144 warn_alloc(gfp_mask, NULL,
3145 "vmalloc error: size %lu, failed to map pages",
3146 area->nr_pages * PAGE_SIZE);
3158 * __vmalloc_node_range - allocate virtually contiguous memory
3159 * @size: allocation size
3160 * @align: desired alignment
3161 * @start: vm area range start
3162 * @end: vm area range end
3163 * @gfp_mask: flags for the page level allocator
3164 * @prot: protection mask for the allocated pages
3165 * @vm_flags: additional vm area flags (e.g. %VM_NO_GUARD)
3166 * @node: node to use for allocation or NUMA_NO_NODE
3167 * @caller: caller's return address
3169 * Allocate enough pages to cover @size from the page level
3170 * allocator with @gfp_mask flags. Please note that the full set of gfp
3171 * flags are not supported. GFP_KERNEL, GFP_NOFS and GFP_NOIO are all
3173 * Zone modifiers are not supported. From the reclaim modifiers
3174 * __GFP_DIRECT_RECLAIM is required (aka GFP_NOWAIT is not supported)
3175 * and only __GFP_NOFAIL is supported (i.e. __GFP_NORETRY and
3176 * __GFP_RETRY_MAYFAIL are not supported).
3178 * __GFP_NOWARN can be used to suppress failures messages.
3180 * Map them into contiguous kernel virtual space, using a pagetable
3181 * protection of @prot.
3183 * Return: the address of the area or %NULL on failure
3185 void *__vmalloc_node_range(unsigned long size, unsigned long align,
3186 unsigned long start, unsigned long end, gfp_t gfp_mask,
3187 pgprot_t prot, unsigned long vm_flags, int node,
3190 struct vm_struct *area;
3192 kasan_vmalloc_flags_t kasan_flags = KASAN_VMALLOC_NONE;
3193 unsigned long real_size = size;
3194 unsigned long real_align = align;
3195 unsigned int shift = PAGE_SHIFT;
3197 if (WARN_ON_ONCE(!size))
3200 if ((size >> PAGE_SHIFT) > totalram_pages()) {
3201 warn_alloc(gfp_mask, NULL,
3202 "vmalloc error: size %lu, exceeds total pages",
3207 if (vmap_allow_huge && (vm_flags & VM_ALLOW_HUGE_VMAP)) {
3208 unsigned long size_per_node;
3211 * Try huge pages. Only try for PAGE_KERNEL allocations,
3212 * others like modules don't yet expect huge pages in
3213 * their allocations due to apply_to_page_range not
3217 size_per_node = size;
3218 if (node == NUMA_NO_NODE)
3219 size_per_node /= num_online_nodes();
3220 if (arch_vmap_pmd_supported(prot) && size_per_node >= PMD_SIZE)
3223 shift = arch_vmap_pte_supported_shift(size_per_node);
3225 align = max(real_align, 1UL << shift);
3226 size = ALIGN(real_size, 1UL << shift);
3230 area = __get_vm_area_node(real_size, align, shift, VM_ALLOC |
3231 VM_UNINITIALIZED | vm_flags, start, end, node,
3234 bool nofail = gfp_mask & __GFP_NOFAIL;
3235 warn_alloc(gfp_mask, NULL,
3236 "vmalloc error: size %lu, vm_struct allocation failed%s",
3237 real_size, (nofail) ? ". Retrying." : "");
3239 schedule_timeout_uninterruptible(1);
3246 * Prepare arguments for __vmalloc_area_node() and
3247 * kasan_unpoison_vmalloc().
3249 if (pgprot_val(prot) == pgprot_val(PAGE_KERNEL)) {
3250 if (kasan_hw_tags_enabled()) {
3252 * Modify protection bits to allow tagging.
3253 * This must be done before mapping.
3255 prot = arch_vmap_pgprot_tagged(prot);
3258 * Skip page_alloc poisoning and zeroing for physical
3259 * pages backing VM_ALLOC mapping. Memory is instead
3260 * poisoned and zeroed by kasan_unpoison_vmalloc().
3262 gfp_mask |= __GFP_SKIP_KASAN | __GFP_SKIP_ZERO;
3265 /* Take note that the mapping is PAGE_KERNEL. */
3266 kasan_flags |= KASAN_VMALLOC_PROT_NORMAL;
3269 /* Allocate physical pages and map them into vmalloc space. */
3270 ret = __vmalloc_area_node(area, gfp_mask, prot, shift, node);
3275 * Mark the pages as accessible, now that they are mapped.
3276 * The condition for setting KASAN_VMALLOC_INIT should complement the
3277 * one in post_alloc_hook() with regards to the __GFP_SKIP_ZERO check
3278 * to make sure that memory is initialized under the same conditions.
3279 * Tag-based KASAN modes only assign tags to normal non-executable
3280 * allocations, see __kasan_unpoison_vmalloc().
3282 kasan_flags |= KASAN_VMALLOC_VM_ALLOC;
3283 if (!want_init_on_free() && want_init_on_alloc(gfp_mask) &&
3284 (gfp_mask & __GFP_SKIP_ZERO))
3285 kasan_flags |= KASAN_VMALLOC_INIT;
3286 /* KASAN_VMALLOC_PROT_NORMAL already set if required. */
3287 area->addr = kasan_unpoison_vmalloc(area->addr, real_size, kasan_flags);
3290 * In this function, newly allocated vm_struct has VM_UNINITIALIZED
3291 * flag. It means that vm_struct is not fully initialized.
3292 * Now, it is fully initialized, so remove this flag here.
3294 clear_vm_uninitialized_flag(area);
3296 size = PAGE_ALIGN(size);
3297 if (!(vm_flags & VM_DEFER_KMEMLEAK))
3298 kmemleak_vmalloc(area, size, gfp_mask);
3303 if (shift > PAGE_SHIFT) {
3314 * __vmalloc_node - allocate virtually contiguous memory
3315 * @size: allocation size
3316 * @align: desired alignment
3317 * @gfp_mask: flags for the page level allocator
3318 * @node: node to use for allocation or NUMA_NO_NODE
3319 * @caller: caller's return address
3321 * Allocate enough pages to cover @size from the page level allocator with
3322 * @gfp_mask flags. Map them into contiguous kernel virtual space.
3324 * Reclaim modifiers in @gfp_mask - __GFP_NORETRY, __GFP_RETRY_MAYFAIL
3325 * and __GFP_NOFAIL are not supported
3327 * Any use of gfp flags outside of GFP_KERNEL should be consulted
3330 * Return: pointer to the allocated memory or %NULL on error
3332 void *__vmalloc_node(unsigned long size, unsigned long align,
3333 gfp_t gfp_mask, int node, const void *caller)
3335 return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
3336 gfp_mask, PAGE_KERNEL, 0, node, caller);
3339 * This is only for performance analysis of vmalloc and stress purpose.
3340 * It is required by vmalloc test module, therefore do not use it other
3343 #ifdef CONFIG_TEST_VMALLOC_MODULE
3344 EXPORT_SYMBOL_GPL(__vmalloc_node);
3347 void *__vmalloc(unsigned long size, gfp_t gfp_mask)
3349 return __vmalloc_node(size, 1, gfp_mask, NUMA_NO_NODE,
3350 __builtin_return_address(0));
3352 EXPORT_SYMBOL(__vmalloc);
3355 * vmalloc - allocate virtually contiguous memory
3356 * @size: allocation size
3358 * Allocate enough pages to cover @size from the page level
3359 * allocator and map them into contiguous kernel virtual space.
3361 * For tight control over page level allocator and protection flags
3362 * use __vmalloc() instead.
3364 * Return: pointer to the allocated memory or %NULL on error
3366 void *vmalloc(unsigned long size)
3368 return __vmalloc_node(size, 1, GFP_KERNEL, NUMA_NO_NODE,
3369 __builtin_return_address(0));
3371 EXPORT_SYMBOL(vmalloc);
3374 * vmalloc_huge - allocate virtually contiguous memory, allow huge pages
3375 * @size: allocation size
3376 * @gfp_mask: flags for the page level allocator
3378 * Allocate enough pages to cover @size from the page level
3379 * allocator and map them into contiguous kernel virtual space.
3380 * If @size is greater than or equal to PMD_SIZE, allow using
3381 * huge pages for the memory
3383 * Return: pointer to the allocated memory or %NULL on error
3385 void *vmalloc_huge(unsigned long size, gfp_t gfp_mask)
3387 return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
3388 gfp_mask, PAGE_KERNEL, VM_ALLOW_HUGE_VMAP,
3389 NUMA_NO_NODE, __builtin_return_address(0));
3391 EXPORT_SYMBOL_GPL(vmalloc_huge);
3394 * vzalloc - allocate virtually contiguous memory with zero fill
3395 * @size: allocation size
3397 * Allocate enough pages to cover @size from the page level
3398 * allocator and map them into contiguous kernel virtual space.
3399 * The memory allocated is set to zero.
3401 * For tight control over page level allocator and protection flags
3402 * use __vmalloc() instead.
3404 * Return: pointer to the allocated memory or %NULL on error
3406 void *vzalloc(unsigned long size)
3408 return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_ZERO, NUMA_NO_NODE,
3409 __builtin_return_address(0));
3411 EXPORT_SYMBOL(vzalloc);
3414 * vmalloc_user - allocate zeroed virtually contiguous memory for userspace
3415 * @size: allocation size
3417 * The resulting memory area is zeroed so it can be mapped to userspace
3418 * without leaking data.
3420 * Return: pointer to the allocated memory or %NULL on error
3422 void *vmalloc_user(unsigned long size)
3424 return __vmalloc_node_range(size, SHMLBA, VMALLOC_START, VMALLOC_END,
3425 GFP_KERNEL | __GFP_ZERO, PAGE_KERNEL,
3426 VM_USERMAP, NUMA_NO_NODE,
3427 __builtin_return_address(0));
3429 EXPORT_SYMBOL(vmalloc_user);
3432 * vmalloc_node - allocate memory on a specific node
3433 * @size: allocation size
3436 * Allocate enough pages to cover @size from the page level
3437 * allocator and map them into contiguous kernel virtual space.
3439 * For tight control over page level allocator and protection flags
3440 * use __vmalloc() instead.
3442 * Return: pointer to the allocated memory or %NULL on error
3444 void *vmalloc_node(unsigned long size, int node)
3446 return __vmalloc_node(size, 1, GFP_KERNEL, node,
3447 __builtin_return_address(0));
3449 EXPORT_SYMBOL(vmalloc_node);
3452 * vzalloc_node - allocate memory on a specific node with zero fill
3453 * @size: allocation size
3456 * Allocate enough pages to cover @size from the page level
3457 * allocator and map them into contiguous kernel virtual space.
3458 * The memory allocated is set to zero.
3460 * Return: pointer to the allocated memory or %NULL on error
3462 void *vzalloc_node(unsigned long size, int node)
3464 return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_ZERO, node,
3465 __builtin_return_address(0));
3467 EXPORT_SYMBOL(vzalloc_node);
3469 #if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32)
3470 #define GFP_VMALLOC32 (GFP_DMA32 | GFP_KERNEL)
3471 #elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA)
3472 #define GFP_VMALLOC32 (GFP_DMA | GFP_KERNEL)
3475 * 64b systems should always have either DMA or DMA32 zones. For others
3476 * GFP_DMA32 should do the right thing and use the normal zone.
3478 #define GFP_VMALLOC32 (GFP_DMA32 | GFP_KERNEL)
3482 * vmalloc_32 - allocate virtually contiguous memory (32bit addressable)
3483 * @size: allocation size
3485 * Allocate enough 32bit PA addressable pages to cover @size from the
3486 * page level allocator and map them into contiguous kernel virtual space.
3488 * Return: pointer to the allocated memory or %NULL on error
3490 void *vmalloc_32(unsigned long size)
3492 return __vmalloc_node(size, 1, GFP_VMALLOC32, NUMA_NO_NODE,
3493 __builtin_return_address(0));
3495 EXPORT_SYMBOL(vmalloc_32);
3498 * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory
3499 * @size: allocation size
3501 * The resulting memory area is 32bit addressable and zeroed so it can be
3502 * mapped to userspace without leaking data.
3504 * Return: pointer to the allocated memory or %NULL on error
3506 void *vmalloc_32_user(unsigned long size)
3508 return __vmalloc_node_range(size, SHMLBA, VMALLOC_START, VMALLOC_END,
3509 GFP_VMALLOC32 | __GFP_ZERO, PAGE_KERNEL,
3510 VM_USERMAP, NUMA_NO_NODE,
3511 __builtin_return_address(0));
3513 EXPORT_SYMBOL(vmalloc_32_user);
3516 * Atomically zero bytes in the iterator.
3518 * Returns the number of zeroed bytes.
3520 static size_t zero_iter(struct iov_iter *iter, size_t count)
3522 size_t remains = count;
3524 while (remains > 0) {
3527 num = remains < PAGE_SIZE ? remains : PAGE_SIZE;
3528 copied = copy_page_to_iter_nofault(ZERO_PAGE(0), 0, num, iter);
3535 return count - remains;
3539 * small helper routine, copy contents to iter from addr.
3540 * If the page is not present, fill zero.
3542 * Returns the number of copied bytes.
3544 static size_t aligned_vread_iter(struct iov_iter *iter,
3545 const char *addr, size_t count)
3547 size_t remains = count;
3550 while (remains > 0) {
3551 unsigned long offset, length;
3554 offset = offset_in_page(addr);
3555 length = PAGE_SIZE - offset;
3556 if (length > remains)
3558 page = vmalloc_to_page(addr);
3560 * To do safe access to this _mapped_ area, we need lock. But
3561 * adding lock here means that we need to add overhead of
3562 * vmalloc()/vfree() calls for this _debug_ interface, rarely
3563 * used. Instead of that, we'll use an local mapping via
3564 * copy_page_to_iter_nofault() and accept a small overhead in
3565 * this access function.
3568 copied = copy_page_to_iter_nofault(page, offset,
3571 copied = zero_iter(iter, length);
3576 if (copied != length)
3580 return count - remains;
3584 * Read from a vm_map_ram region of memory.
3586 * Returns the number of copied bytes.
3588 static size_t vmap_ram_vread_iter(struct iov_iter *iter, const char *addr,
3589 size_t count, unsigned long flags)
3592 struct vmap_block *vb;
3594 unsigned long offset;
3595 unsigned int rs, re;
3599 * If it's area created by vm_map_ram() interface directly, but
3600 * not further subdividing and delegating management to vmap_block,
3603 if (!(flags & VMAP_BLOCK))
3604 return aligned_vread_iter(iter, addr, count);
3609 * Area is split into regions and tracked with vmap_block, read out
3610 * each region and zero fill the hole between regions.
3612 xa = addr_to_vb_xa((unsigned long) addr);
3613 vb = xa_load(xa, addr_to_vb_idx((unsigned long)addr));
3617 spin_lock(&vb->lock);
3618 if (bitmap_empty(vb->used_map, VMAP_BBMAP_BITS)) {
3619 spin_unlock(&vb->lock);
3623 for_each_set_bitrange(rs, re, vb->used_map, VMAP_BBMAP_BITS) {
3629 start = vmap_block_vaddr(vb->va->va_start, rs);
3632 size_t to_zero = min_t(size_t, start - addr, remains);
3633 size_t zeroed = zero_iter(iter, to_zero);
3638 if (remains == 0 || zeroed != to_zero)
3642 /*it could start reading from the middle of used region*/
3643 offset = offset_in_page(addr);
3644 n = ((re - rs + 1) << PAGE_SHIFT) - offset;
3648 copied = aligned_vread_iter(iter, start + offset, n);
3657 spin_unlock(&vb->lock);
3660 /* zero-fill the left dirty or free regions */
3661 return count - remains + zero_iter(iter, remains);
3663 /* We couldn't copy/zero everything */
3664 spin_unlock(&vb->lock);
3665 return count - remains;
3669 * vread_iter() - read vmalloc area in a safe way to an iterator.
3670 * @iter: the iterator to which data should be written.
3671 * @addr: vm address.
3672 * @count: number of bytes to be read.
3674 * This function checks that addr is a valid vmalloc'ed area, and
3675 * copy data from that area to a given buffer. If the given memory range
3676 * of [addr...addr+count) includes some valid address, data is copied to
3677 * proper area of @buf. If there are memory holes, they'll be zero-filled.
3678 * IOREMAP area is treated as memory hole and no copy is done.
3680 * If [addr...addr+count) doesn't includes any intersects with alive
3681 * vm_struct area, returns 0. @buf should be kernel's buffer.
3683 * Note: In usual ops, vread() is never necessary because the caller
3684 * should know vmalloc() area is valid and can use memcpy().
3685 * This is for routines which have to access vmalloc area without
3686 * any information, as /proc/kcore.
3688 * Return: number of bytes for which addr and buf should be increased
3689 * (same number as @count) or %0 if [addr...addr+count) doesn't
3690 * include any intersection with valid vmalloc area
3692 long vread_iter(struct iov_iter *iter, const char *addr, size_t count)
3694 struct vmap_area *va;
3695 struct vm_struct *vm;
3697 size_t n, size, flags, remains;
3699 addr = kasan_reset_tag(addr);
3701 /* Don't allow overflow */
3702 if ((unsigned long) addr + count < count)
3703 count = -(unsigned long) addr;
3707 spin_lock(&vmap_area_lock);
3708 va = find_vmap_area_exceed_addr((unsigned long)addr);
3712 /* no intersects with alive vmap_area */
3713 if ((unsigned long)addr + remains <= va->va_start)
3716 list_for_each_entry_from(va, &vmap_area_list, list) {
3723 flags = va->flags & VMAP_FLAGS_MASK;
3725 * VMAP_BLOCK indicates a sub-type of vm_map_ram area, need
3726 * be set together with VMAP_RAM.
3728 WARN_ON(flags == VMAP_BLOCK);
3733 if (vm && (vm->flags & VM_UNINITIALIZED))
3736 /* Pair with smp_wmb() in clear_vm_uninitialized_flag() */
3739 vaddr = (char *) va->va_start;
3740 size = vm ? get_vm_area_size(vm) : va_size(va);
3742 if (addr >= vaddr + size)
3746 size_t to_zero = min_t(size_t, vaddr - addr, remains);
3747 size_t zeroed = zero_iter(iter, to_zero);
3752 if (remains == 0 || zeroed != to_zero)
3756 n = vaddr + size - addr;
3760 if (flags & VMAP_RAM)
3761 copied = vmap_ram_vread_iter(iter, addr, n, flags);
3762 else if (!(vm->flags & VM_IOREMAP))
3763 copied = aligned_vread_iter(iter, addr, n);
3764 else /* IOREMAP area is treated as memory hole */
3765 copied = zero_iter(iter, n);
3775 spin_unlock(&vmap_area_lock);
3776 /* zero-fill memory holes */
3777 return count - remains + zero_iter(iter, remains);
3779 /* Nothing remains, or We couldn't copy/zero everything. */
3780 spin_unlock(&vmap_area_lock);
3782 return count - remains;
3786 * remap_vmalloc_range_partial - map vmalloc pages to userspace
3787 * @vma: vma to cover
3788 * @uaddr: target user address to start at
3789 * @kaddr: virtual address of vmalloc kernel memory
3790 * @pgoff: offset from @kaddr to start at
3791 * @size: size of map area
3793 * Returns: 0 for success, -Exxx on failure
3795 * This function checks that @kaddr is a valid vmalloc'ed area,
3796 * and that it is big enough to cover the range starting at
3797 * @uaddr in @vma. Will return failure if that criteria isn't
3800 * Similar to remap_pfn_range() (see mm/memory.c)
3802 int remap_vmalloc_range_partial(struct vm_area_struct *vma, unsigned long uaddr,
3803 void *kaddr, unsigned long pgoff,
3806 struct vm_struct *area;
3808 unsigned long end_index;
3810 if (check_shl_overflow(pgoff, PAGE_SHIFT, &off))
3813 size = PAGE_ALIGN(size);
3815 if (!PAGE_ALIGNED(uaddr) || !PAGE_ALIGNED(kaddr))
3818 area = find_vm_area(kaddr);
3822 if (!(area->flags & (VM_USERMAP | VM_DMA_COHERENT)))
3825 if (check_add_overflow(size, off, &end_index) ||
3826 end_index > get_vm_area_size(area))
3831 struct page *page = vmalloc_to_page(kaddr);
3834 ret = vm_insert_page(vma, uaddr, page);
3843 vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
3849 * remap_vmalloc_range - map vmalloc pages to userspace
3850 * @vma: vma to cover (map full range of vma)
3851 * @addr: vmalloc memory
3852 * @pgoff: number of pages into addr before first page to map
3854 * Returns: 0 for success, -Exxx on failure
3856 * This function checks that addr is a valid vmalloc'ed area, and
3857 * that it is big enough to cover the vma. Will return failure if
3858 * that criteria isn't met.
3860 * Similar to remap_pfn_range() (see mm/memory.c)
3862 int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
3863 unsigned long pgoff)
3865 return remap_vmalloc_range_partial(vma, vma->vm_start,
3867 vma->vm_end - vma->vm_start);
3869 EXPORT_SYMBOL(remap_vmalloc_range);
3871 void free_vm_area(struct vm_struct *area)
3873 struct vm_struct *ret;
3874 ret = remove_vm_area(area->addr);
3875 BUG_ON(ret != area);
3878 EXPORT_SYMBOL_GPL(free_vm_area);
3881 static struct vmap_area *node_to_va(struct rb_node *n)
3883 return rb_entry_safe(n, struct vmap_area, rb_node);
3887 * pvm_find_va_enclose_addr - find the vmap_area @addr belongs to
3888 * @addr: target address
3890 * Returns: vmap_area if it is found. If there is no such area
3891 * the first highest(reverse order) vmap_area is returned
3892 * i.e. va->va_start < addr && va->va_end < addr or NULL
3893 * if there are no any areas before @addr.
3895 static struct vmap_area *
3896 pvm_find_va_enclose_addr(unsigned long addr)
3898 struct vmap_area *va, *tmp;
3901 n = free_vmap_area_root.rb_node;
3905 tmp = rb_entry(n, struct vmap_area, rb_node);
3906 if (tmp->va_start <= addr) {
3908 if (tmp->va_end >= addr)
3921 * pvm_determine_end_from_reverse - find the highest aligned address
3922 * of free block below VMALLOC_END
3924 * in - the VA we start the search(reverse order);
3925 * out - the VA with the highest aligned end address.
3926 * @align: alignment for required highest address
3928 * Returns: determined end address within vmap_area
3930 static unsigned long
3931 pvm_determine_end_from_reverse(struct vmap_area **va, unsigned long align)
3933 unsigned long vmalloc_end = VMALLOC_END & ~(align - 1);
3937 list_for_each_entry_from_reverse((*va),
3938 &free_vmap_area_list, list) {
3939 addr = min((*va)->va_end & ~(align - 1), vmalloc_end);
3940 if ((*va)->va_start < addr)
3949 * pcpu_get_vm_areas - allocate vmalloc areas for percpu allocator
3950 * @offsets: array containing offset of each area
3951 * @sizes: array containing size of each area
3952 * @nr_vms: the number of areas to allocate
3953 * @align: alignment, all entries in @offsets and @sizes must be aligned to this
3955 * Returns: kmalloc'd vm_struct pointer array pointing to allocated
3956 * vm_structs on success, %NULL on failure
3958 * Percpu allocator wants to use congruent vm areas so that it can
3959 * maintain the offsets among percpu areas. This function allocates
3960 * congruent vmalloc areas for it with GFP_KERNEL. These areas tend to
3961 * be scattered pretty far, distance between two areas easily going up
3962 * to gigabytes. To avoid interacting with regular vmallocs, these
3963 * areas are allocated from top.
3965 * Despite its complicated look, this allocator is rather simple. It
3966 * does everything top-down and scans free blocks from the end looking
3967 * for matching base. While scanning, if any of the areas do not fit the
3968 * base address is pulled down to fit the area. Scanning is repeated till
3969 * all the areas fit and then all necessary data structures are inserted
3970 * and the result is returned.
3972 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
3973 const size_t *sizes, int nr_vms,
3976 const unsigned long vmalloc_start = ALIGN(VMALLOC_START, align);
3977 const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1);
3978 struct vmap_area **vas, *va;
3979 struct vm_struct **vms;
3980 int area, area2, last_area, term_area;
3981 unsigned long base, start, size, end, last_end, orig_start, orig_end;
3982 bool purged = false;
3984 /* verify parameters and allocate data structures */
3985 BUG_ON(offset_in_page(align) || !is_power_of_2(align));
3986 for (last_area = 0, area = 0; area < nr_vms; area++) {
3987 start = offsets[area];
3988 end = start + sizes[area];
3990 /* is everything aligned properly? */
3991 BUG_ON(!IS_ALIGNED(offsets[area], align));
3992 BUG_ON(!IS_ALIGNED(sizes[area], align));
3994 /* detect the area with the highest address */
3995 if (start > offsets[last_area])
3998 for (area2 = area + 1; area2 < nr_vms; area2++) {
3999 unsigned long start2 = offsets[area2];
4000 unsigned long end2 = start2 + sizes[area2];
4002 BUG_ON(start2 < end && start < end2);
4005 last_end = offsets[last_area] + sizes[last_area];
4007 if (vmalloc_end - vmalloc_start < last_end) {
4012 vms = kcalloc(nr_vms, sizeof(vms[0]), GFP_KERNEL);
4013 vas = kcalloc(nr_vms, sizeof(vas[0]), GFP_KERNEL);
4017 for (area = 0; area < nr_vms; area++) {
4018 vas[area] = kmem_cache_zalloc(vmap_area_cachep, GFP_KERNEL);
4019 vms[area] = kzalloc(sizeof(struct vm_struct), GFP_KERNEL);
4020 if (!vas[area] || !vms[area])
4024 spin_lock(&free_vmap_area_lock);
4026 /* start scanning - we scan from the top, begin with the last area */
4027 area = term_area = last_area;
4028 start = offsets[area];
4029 end = start + sizes[area];
4031 va = pvm_find_va_enclose_addr(vmalloc_end);
4032 base = pvm_determine_end_from_reverse(&va, align) - end;
4036 * base might have underflowed, add last_end before
4039 if (base + last_end < vmalloc_start + last_end)
4043 * Fitting base has not been found.
4049 * If required width exceeds current VA block, move
4050 * base downwards and then recheck.
4052 if (base + end > va->va_end) {
4053 base = pvm_determine_end_from_reverse(&va, align) - end;
4059 * If this VA does not fit, move base downwards and recheck.
4061 if (base + start < va->va_start) {
4062 va = node_to_va(rb_prev(&va->rb_node));
4063 base = pvm_determine_end_from_reverse(&va, align) - end;
4069 * This area fits, move on to the previous one. If
4070 * the previous one is the terminal one, we're done.
4072 area = (area + nr_vms - 1) % nr_vms;
4073 if (area == term_area)
4076 start = offsets[area];
4077 end = start + sizes[area];
4078 va = pvm_find_va_enclose_addr(base + end);
4081 /* we've found a fitting base, insert all va's */
4082 for (area = 0; area < nr_vms; area++) {
4085 start = base + offsets[area];
4088 va = pvm_find_va_enclose_addr(start);
4089 if (WARN_ON_ONCE(va == NULL))
4090 /* It is a BUG(), but trigger recovery instead. */
4093 ret = adjust_va_to_fit_type(&free_vmap_area_root,
4094 &free_vmap_area_list,
4096 if (WARN_ON_ONCE(unlikely(ret)))
4097 /* It is a BUG(), but trigger recovery instead. */
4100 /* Allocated area. */
4102 va->va_start = start;
4103 va->va_end = start + size;
4106 spin_unlock(&free_vmap_area_lock);
4108 /* populate the kasan shadow space */
4109 for (area = 0; area < nr_vms; area++) {
4110 if (kasan_populate_vmalloc(vas[area]->va_start, sizes[area]))
4111 goto err_free_shadow;
4114 /* insert all vm's */
4115 spin_lock(&vmap_area_lock);
4116 for (area = 0; area < nr_vms; area++) {
4117 insert_vmap_area(vas[area], &vmap_area_root, &vmap_area_list);
4119 setup_vmalloc_vm_locked(vms[area], vas[area], VM_ALLOC,
4122 spin_unlock(&vmap_area_lock);
4125 * Mark allocated areas as accessible. Do it now as a best-effort
4126 * approach, as they can be mapped outside of vmalloc code.
4127 * With hardware tag-based KASAN, marking is skipped for
4128 * non-VM_ALLOC mappings, see __kasan_unpoison_vmalloc().
4130 for (area = 0; area < nr_vms; area++)
4131 vms[area]->addr = kasan_unpoison_vmalloc(vms[area]->addr,
4132 vms[area]->size, KASAN_VMALLOC_PROT_NORMAL);
4139 * Remove previously allocated areas. There is no
4140 * need in removing these areas from the busy tree,
4141 * because they are inserted only on the final step
4142 * and when pcpu_get_vm_areas() is success.
4145 orig_start = vas[area]->va_start;
4146 orig_end = vas[area]->va_end;
4147 va = merge_or_add_vmap_area_augment(vas[area], &free_vmap_area_root,
4148 &free_vmap_area_list);
4150 kasan_release_vmalloc(orig_start, orig_end,
4151 va->va_start, va->va_end);
4156 spin_unlock(&free_vmap_area_lock);
4158 purge_vmap_area_lazy();
4161 /* Before "retry", check if we recover. */
4162 for (area = 0; area < nr_vms; area++) {
4166 vas[area] = kmem_cache_zalloc(
4167 vmap_area_cachep, GFP_KERNEL);
4176 for (area = 0; area < nr_vms; area++) {
4178 kmem_cache_free(vmap_area_cachep, vas[area]);
4188 spin_lock(&free_vmap_area_lock);
4190 * We release all the vmalloc shadows, even the ones for regions that
4191 * hadn't been successfully added. This relies on kasan_release_vmalloc
4192 * being able to tolerate this case.
4194 for (area = 0; area < nr_vms; area++) {
4195 orig_start = vas[area]->va_start;
4196 orig_end = vas[area]->va_end;
4197 va = merge_or_add_vmap_area_augment(vas[area], &free_vmap_area_root,
4198 &free_vmap_area_list);
4200 kasan_release_vmalloc(orig_start, orig_end,
4201 va->va_start, va->va_end);
4205 spin_unlock(&free_vmap_area_lock);
4212 * pcpu_free_vm_areas - free vmalloc areas for percpu allocator
4213 * @vms: vm_struct pointer array returned by pcpu_get_vm_areas()
4214 * @nr_vms: the number of allocated areas
4216 * Free vm_structs and the array allocated by pcpu_get_vm_areas().
4218 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
4222 for (i = 0; i < nr_vms; i++)
4223 free_vm_area(vms[i]);
4226 #endif /* CONFIG_SMP */
4228 #ifdef CONFIG_PRINTK
4229 bool vmalloc_dump_obj(void *object)
4231 struct vm_struct *vm;
4232 void *objp = (void *)PAGE_ALIGN((unsigned long)object);
4234 vm = find_vm_area(objp);
4237 pr_cont(" %u-page vmalloc region starting at %#lx allocated at %pS\n",
4238 vm->nr_pages, (unsigned long)vm->addr, vm->caller);
4243 #ifdef CONFIG_PROC_FS
4244 static void *s_start(struct seq_file *m, loff_t *pos)
4245 __acquires(&vmap_purge_lock)
4246 __acquires(&vmap_area_lock)
4248 mutex_lock(&vmap_purge_lock);
4249 spin_lock(&vmap_area_lock);
4251 return seq_list_start(&vmap_area_list, *pos);
4254 static void *s_next(struct seq_file *m, void *p, loff_t *pos)
4256 return seq_list_next(p, &vmap_area_list, pos);
4259 static void s_stop(struct seq_file *m, void *p)
4260 __releases(&vmap_area_lock)
4261 __releases(&vmap_purge_lock)
4263 spin_unlock(&vmap_area_lock);
4264 mutex_unlock(&vmap_purge_lock);
4267 static void show_numa_info(struct seq_file *m, struct vm_struct *v)
4269 if (IS_ENABLED(CONFIG_NUMA)) {
4270 unsigned int nr, *counters = m->private;
4271 unsigned int step = 1U << vm_area_page_order(v);
4276 if (v->flags & VM_UNINITIALIZED)
4278 /* Pair with smp_wmb() in clear_vm_uninitialized_flag() */
4281 memset(counters, 0, nr_node_ids * sizeof(unsigned int));
4283 for (nr = 0; nr < v->nr_pages; nr += step)
4284 counters[page_to_nid(v->pages[nr])] += step;
4285 for_each_node_state(nr, N_HIGH_MEMORY)
4287 seq_printf(m, " N%u=%u", nr, counters[nr]);
4291 static void show_purge_info(struct seq_file *m)
4293 struct vmap_area *va;
4295 spin_lock(&purge_vmap_area_lock);
4296 list_for_each_entry(va, &purge_vmap_area_list, list) {
4297 seq_printf(m, "0x%pK-0x%pK %7ld unpurged vm_area\n",
4298 (void *)va->va_start, (void *)va->va_end,
4299 va->va_end - va->va_start);
4301 spin_unlock(&purge_vmap_area_lock);
4304 static int s_show(struct seq_file *m, void *p)
4306 struct vmap_area *va;
4307 struct vm_struct *v;
4309 va = list_entry(p, struct vmap_area, list);
4312 if (va->flags & VMAP_RAM)
4313 seq_printf(m, "0x%pK-0x%pK %7ld vm_map_ram\n",
4314 (void *)va->va_start, (void *)va->va_end,
4315 va->va_end - va->va_start);
4322 seq_printf(m, "0x%pK-0x%pK %7ld",
4323 v->addr, v->addr + v->size, v->size);
4326 seq_printf(m, " %pS", v->caller);
4329 seq_printf(m, " pages=%d", v->nr_pages);
4332 seq_printf(m, " phys=%pa", &v->phys_addr);
4334 if (v->flags & VM_IOREMAP)
4335 seq_puts(m, " ioremap");
4337 if (v->flags & VM_ALLOC)
4338 seq_puts(m, " vmalloc");
4340 if (v->flags & VM_MAP)
4341 seq_puts(m, " vmap");
4343 if (v->flags & VM_USERMAP)
4344 seq_puts(m, " user");
4346 if (v->flags & VM_DMA_COHERENT)
4347 seq_puts(m, " dma-coherent");
4349 if (is_vmalloc_addr(v->pages))
4350 seq_puts(m, " vpages");
4352 show_numa_info(m, v);
4356 * As a final step, dump "unpurged" areas.
4359 if (list_is_last(&va->list, &vmap_area_list))
4365 static const struct seq_operations vmalloc_op = {
4372 static int __init proc_vmalloc_init(void)
4374 if (IS_ENABLED(CONFIG_NUMA))
4375 proc_create_seq_private("vmallocinfo", 0400, NULL,
4377 nr_node_ids * sizeof(unsigned int), NULL);
4379 proc_create_seq("vmallocinfo", 0400, NULL, &vmalloc_op);
4382 module_init(proc_vmalloc_init);
4386 void __init vmalloc_init(void)
4388 struct vmap_area *va;
4389 struct vm_struct *tmp;
4393 * Create the cache for vmap_area objects.
4395 vmap_area_cachep = KMEM_CACHE(vmap_area, SLAB_PANIC);
4397 for_each_possible_cpu(i) {
4398 struct vmap_block_queue *vbq;
4399 struct vfree_deferred *p;
4401 vbq = &per_cpu(vmap_block_queue, i);
4402 spin_lock_init(&vbq->lock);
4403 INIT_LIST_HEAD(&vbq->free);
4404 p = &per_cpu(vfree_deferred, i);
4405 init_llist_head(&p->list);
4406 INIT_WORK(&p->wq, delayed_vfree_work);
4407 xa_init(&vbq->vmap_blocks);
4410 /* Import existing vmlist entries. */
4411 for (tmp = vmlist; tmp; tmp = tmp->next) {
4412 va = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
4413 if (WARN_ON_ONCE(!va))
4416 va->va_start = (unsigned long)tmp->addr;
4417 va->va_end = va->va_start + tmp->size;
4419 insert_vmap_area(va, &vmap_area_root, &vmap_area_list);
4423 * Now we can initialize a free vmap space.
4425 vmap_init_free_space();
4426 vmap_initialized = true;