mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-11-01 08:58:07 +00:00
85e853c5ec
Pull RCU updates from Paul E. McKenney: - Documentation updates. - Miscellaneous fixes. - kfree_rcu() updates: Addition of mem_dump_obj() to provide allocator return addresses to more easily locate bugs. This has a couple of RCU-related commits, but is mostly MM. Was pulled in with akpm's agreement. - Per-callback-batch tracking of numbers of callbacks, which enables better debugging information and smarter reactions to large numbers of callbacks. - The first round of changes to allow CPUs to be runtime switched from and to callback-offloaded state. - CONFIG_PREEMPT_RT-related changes. - RCU CPU stall warning updates. - Addition of polling grace-period APIs for SRCU. - Torture-test and torture-test scripting updates, including a "torture everything" script that runs rcutorture, locktorture, scftorture, rcuscale, and refscale. Plus does an allmodconfig build. Signed-off-by: Ingo Molnar <mingo@kernel.org>
3609 lines
92 KiB
C
3609 lines
92 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (C) 1993 Linus Torvalds
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* Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
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* SMP-safe vmalloc/vfree/ioremap, Tigran Aivazian <tigran@veritas.com>, May 2000
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* Major rework to support vmap/vunmap, Christoph Hellwig, SGI, August 2002
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* Numa awareness, Christoph Lameter, SGI, June 2005
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* Improving global KVA allocator, Uladzislau Rezki, Sony, May 2019
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*/
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#include <linux/vmalloc.h>
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#include <linux/mm.h>
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#include <linux/module.h>
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#include <linux/highmem.h>
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#include <linux/sched/signal.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/interrupt.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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#include <linux/set_memory.h>
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#include <linux/debugobjects.h>
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#include <linux/kallsyms.h>
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#include <linux/list.h>
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#include <linux/notifier.h>
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#include <linux/rbtree.h>
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#include <linux/xarray.h>
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#include <linux/rcupdate.h>
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#include <linux/pfn.h>
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#include <linux/kmemleak.h>
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#include <linux/atomic.h>
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#include <linux/compiler.h>
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#include <linux/llist.h>
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#include <linux/bitops.h>
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#include <linux/rbtree_augmented.h>
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#include <linux/overflow.h>
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#include <linux/uaccess.h>
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#include <asm/tlbflush.h>
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#include <asm/shmparam.h>
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#include "internal.h"
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#include "pgalloc-track.h"
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bool is_vmalloc_addr(const void *x)
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{
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unsigned long addr = (unsigned long)x;
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return addr >= VMALLOC_START && addr < VMALLOC_END;
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}
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EXPORT_SYMBOL(is_vmalloc_addr);
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struct vfree_deferred {
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struct llist_head list;
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struct work_struct wq;
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};
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static DEFINE_PER_CPU(struct vfree_deferred, vfree_deferred);
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static void __vunmap(const void *, int);
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static void free_work(struct work_struct *w)
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{
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struct vfree_deferred *p = container_of(w, struct vfree_deferred, wq);
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struct llist_node *t, *llnode;
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llist_for_each_safe(llnode, t, llist_del_all(&p->list))
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__vunmap((void *)llnode, 1);
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}
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/*** Page table manipulation functions ***/
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static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
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pgtbl_mod_mask *mask)
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{
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pte_t *pte;
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pte = pte_offset_kernel(pmd, addr);
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do {
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pte_t ptent = ptep_get_and_clear(&init_mm, addr, pte);
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WARN_ON(!pte_none(ptent) && !pte_present(ptent));
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} while (pte++, addr += PAGE_SIZE, addr != end);
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*mask |= PGTBL_PTE_MODIFIED;
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}
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static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
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pgtbl_mod_mask *mask)
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{
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pmd_t *pmd;
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unsigned long next;
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int cleared;
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pmd = pmd_offset(pud, addr);
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do {
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next = pmd_addr_end(addr, end);
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cleared = pmd_clear_huge(pmd);
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if (cleared || pmd_bad(*pmd))
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*mask |= PGTBL_PMD_MODIFIED;
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if (cleared)
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continue;
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if (pmd_none_or_clear_bad(pmd))
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continue;
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vunmap_pte_range(pmd, addr, next, mask);
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cond_resched();
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} while (pmd++, addr = next, addr != end);
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}
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static void vunmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
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pgtbl_mod_mask *mask)
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{
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pud_t *pud;
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unsigned long next;
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int cleared;
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pud = pud_offset(p4d, addr);
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do {
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next = pud_addr_end(addr, end);
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cleared = pud_clear_huge(pud);
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if (cleared || pud_bad(*pud))
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*mask |= PGTBL_PUD_MODIFIED;
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if (cleared)
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continue;
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if (pud_none_or_clear_bad(pud))
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continue;
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vunmap_pmd_range(pud, addr, next, mask);
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} while (pud++, addr = next, addr != end);
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}
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static void vunmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
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pgtbl_mod_mask *mask)
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{
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p4d_t *p4d;
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unsigned long next;
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int cleared;
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p4d = p4d_offset(pgd, addr);
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do {
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next = p4d_addr_end(addr, end);
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cleared = p4d_clear_huge(p4d);
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if (cleared || p4d_bad(*p4d))
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*mask |= PGTBL_P4D_MODIFIED;
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if (cleared)
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continue;
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if (p4d_none_or_clear_bad(p4d))
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continue;
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vunmap_pud_range(p4d, addr, next, mask);
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} while (p4d++, addr = next, addr != end);
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}
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/**
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* unmap_kernel_range_noflush - unmap kernel VM area
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* @start: start of the VM area to unmap
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* @size: size of the VM area to unmap
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*
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* Unmap PFN_UP(@size) pages at @addr. The VM area @addr and @size specify
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* should have been allocated using get_vm_area() and its friends.
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*
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* NOTE:
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* This function does NOT do any cache flushing. The caller is responsible
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* for calling flush_cache_vunmap() on to-be-mapped areas before calling this
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* function and flush_tlb_kernel_range() after.
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*/
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void unmap_kernel_range_noflush(unsigned long start, unsigned long size)
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{
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unsigned long end = start + size;
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unsigned long next;
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pgd_t *pgd;
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unsigned long addr = start;
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pgtbl_mod_mask mask = 0;
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BUG_ON(addr >= end);
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pgd = pgd_offset_k(addr);
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do {
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next = pgd_addr_end(addr, end);
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if (pgd_bad(*pgd))
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mask |= PGTBL_PGD_MODIFIED;
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if (pgd_none_or_clear_bad(pgd))
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continue;
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vunmap_p4d_range(pgd, addr, next, &mask);
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} while (pgd++, addr = next, addr != end);
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if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
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arch_sync_kernel_mappings(start, end);
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}
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static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
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unsigned long end, pgprot_t prot, struct page **pages, int *nr,
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pgtbl_mod_mask *mask)
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{
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pte_t *pte;
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/*
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* nr is a running index into the array which helps higher level
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* callers keep track of where we're up to.
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*/
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pte = pte_alloc_kernel_track(pmd, addr, mask);
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if (!pte)
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return -ENOMEM;
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do {
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struct page *page = pages[*nr];
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if (WARN_ON(!pte_none(*pte)))
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return -EBUSY;
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if (WARN_ON(!page))
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return -ENOMEM;
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set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
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(*nr)++;
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} while (pte++, addr += PAGE_SIZE, addr != end);
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*mask |= PGTBL_PTE_MODIFIED;
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return 0;
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}
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static int vmap_pmd_range(pud_t *pud, unsigned long addr,
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unsigned long end, pgprot_t prot, struct page **pages, int *nr,
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pgtbl_mod_mask *mask)
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{
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pmd_t *pmd;
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unsigned long next;
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pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
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if (!pmd)
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return -ENOMEM;
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do {
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next = pmd_addr_end(addr, end);
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if (vmap_pte_range(pmd, addr, next, prot, pages, nr, mask))
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return -ENOMEM;
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} while (pmd++, addr = next, addr != end);
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return 0;
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}
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static int vmap_pud_range(p4d_t *p4d, unsigned long addr,
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unsigned long end, pgprot_t prot, struct page **pages, int *nr,
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pgtbl_mod_mask *mask)
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{
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pud_t *pud;
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unsigned long next;
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pud = pud_alloc_track(&init_mm, p4d, addr, mask);
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if (!pud)
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return -ENOMEM;
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do {
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next = pud_addr_end(addr, end);
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if (vmap_pmd_range(pud, addr, next, prot, pages, nr, mask))
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return -ENOMEM;
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} while (pud++, addr = next, addr != end);
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return 0;
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}
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static int vmap_p4d_range(pgd_t *pgd, unsigned long addr,
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unsigned long end, pgprot_t prot, struct page **pages, int *nr,
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pgtbl_mod_mask *mask)
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{
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p4d_t *p4d;
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unsigned long next;
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p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
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if (!p4d)
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return -ENOMEM;
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do {
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next = p4d_addr_end(addr, end);
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if (vmap_pud_range(p4d, addr, next, prot, pages, nr, mask))
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return -ENOMEM;
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} while (p4d++, addr = next, addr != end);
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return 0;
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}
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/**
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* map_kernel_range_noflush - map kernel VM area with the specified pages
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* @addr: start of the VM area to map
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* @size: size of the VM area to map
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* @prot: page protection flags to use
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* @pages: pages to map
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*
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* Map PFN_UP(@size) pages at @addr. The VM area @addr and @size specify should
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* have been allocated using get_vm_area() and its friends.
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*
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* NOTE:
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* This function does NOT do any cache flushing. The caller is responsible for
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* calling flush_cache_vmap() on to-be-mapped areas before calling this
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* function.
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*
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* RETURNS:
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* 0 on success, -errno on failure.
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*/
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int map_kernel_range_noflush(unsigned long addr, unsigned long size,
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pgprot_t prot, struct page **pages)
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{
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unsigned long start = addr;
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unsigned long end = addr + size;
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unsigned long next;
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pgd_t *pgd;
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int err = 0;
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int nr = 0;
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pgtbl_mod_mask mask = 0;
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BUG_ON(addr >= end);
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pgd = pgd_offset_k(addr);
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do {
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next = pgd_addr_end(addr, end);
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if (pgd_bad(*pgd))
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mask |= PGTBL_PGD_MODIFIED;
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err = vmap_p4d_range(pgd, addr, next, prot, pages, &nr, &mask);
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if (err)
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return err;
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} while (pgd++, addr = next, addr != end);
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if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
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arch_sync_kernel_mappings(start, end);
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return 0;
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}
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int map_kernel_range(unsigned long start, unsigned long size, pgprot_t prot,
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struct page **pages)
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{
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int ret;
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ret = map_kernel_range_noflush(start, size, prot, pages);
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flush_cache_vmap(start, start + size);
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return ret;
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}
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int is_vmalloc_or_module_addr(const void *x)
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{
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/*
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* ARM, x86-64 and sparc64 put modules in a special place,
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* and fall back on vmalloc() if that fails. Others
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* just put it in the vmalloc space.
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*/
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#if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
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unsigned long addr = (unsigned long)x;
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if (addr >= MODULES_VADDR && addr < MODULES_END)
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return 1;
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#endif
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return is_vmalloc_addr(x);
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}
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/*
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* Walk a vmap address to the struct page it maps.
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*/
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struct page *vmalloc_to_page(const void *vmalloc_addr)
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{
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unsigned long addr = (unsigned long) vmalloc_addr;
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struct page *page = NULL;
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pgd_t *pgd = pgd_offset_k(addr);
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p4d_t *p4d;
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pud_t *pud;
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pmd_t *pmd;
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pte_t *ptep, pte;
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/*
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* XXX we might need to change this if we add VIRTUAL_BUG_ON for
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* architectures that do not vmalloc module space
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*/
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VIRTUAL_BUG_ON(!is_vmalloc_or_module_addr(vmalloc_addr));
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if (pgd_none(*pgd))
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return NULL;
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p4d = p4d_offset(pgd, addr);
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if (p4d_none(*p4d))
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return NULL;
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pud = pud_offset(p4d, addr);
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/*
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* Don't dereference bad PUD or PMD (below) entries. This will also
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* identify huge mappings, which we may encounter on architectures
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* that define CONFIG_HAVE_ARCH_HUGE_VMAP=y. Such regions will be
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* identified as vmalloc addresses by is_vmalloc_addr(), but are
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* not [unambiguously] associated with a struct page, so there is
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* no correct value to return for them.
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*/
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WARN_ON_ONCE(pud_bad(*pud));
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if (pud_none(*pud) || pud_bad(*pud))
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return NULL;
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pmd = pmd_offset(pud, addr);
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WARN_ON_ONCE(pmd_bad(*pmd));
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if (pmd_none(*pmd) || pmd_bad(*pmd))
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return NULL;
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ptep = pte_offset_map(pmd, addr);
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pte = *ptep;
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if (pte_present(pte))
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page = pte_page(pte);
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pte_unmap(ptep);
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return page;
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}
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EXPORT_SYMBOL(vmalloc_to_page);
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/*
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* Map a vmalloc()-space virtual address to the physical page frame number.
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*/
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unsigned long vmalloc_to_pfn(const void *vmalloc_addr)
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{
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return page_to_pfn(vmalloc_to_page(vmalloc_addr));
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}
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EXPORT_SYMBOL(vmalloc_to_pfn);
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/*** Global kva allocator ***/
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#define DEBUG_AUGMENT_PROPAGATE_CHECK 0
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#define DEBUG_AUGMENT_LOWEST_MATCH_CHECK 0
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static DEFINE_SPINLOCK(vmap_area_lock);
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static DEFINE_SPINLOCK(free_vmap_area_lock);
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/* Export for kexec only */
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LIST_HEAD(vmap_area_list);
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static struct rb_root vmap_area_root = RB_ROOT;
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static bool vmap_initialized __read_mostly;
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static struct rb_root purge_vmap_area_root = RB_ROOT;
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static LIST_HEAD(purge_vmap_area_list);
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static DEFINE_SPINLOCK(purge_vmap_area_lock);
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/*
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* This kmem_cache is used for vmap_area objects. Instead of
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* allocating from slab we reuse an object from this cache to
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* make things faster. Especially in "no edge" splitting of
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* free block.
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*/
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static struct kmem_cache *vmap_area_cachep;
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/*
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* This linked list is used in pair with free_vmap_area_root.
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* It gives O(1) access to prev/next to perform fast coalescing.
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*/
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static LIST_HEAD(free_vmap_area_list);
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/*
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* This augment red-black tree represents the free vmap space.
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* All vmap_area objects in this tree are sorted by va->va_start
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* address. It is used for allocation and merging when a vmap
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* object is released.
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*
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* Each vmap_area node contains a maximum available free block
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* of its sub-tree, right or left. Therefore it is possible to
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* find a lowest match of free area.
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*/
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static struct rb_root free_vmap_area_root = RB_ROOT;
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/*
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* Preload a CPU with one object for "no edge" split case. The
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* aim is to get rid of allocations from the atomic context, thus
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* to use more permissive allocation masks.
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*/
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static DEFINE_PER_CPU(struct vmap_area *, ne_fit_preload_node);
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static __always_inline unsigned long
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va_size(struct vmap_area *va)
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{
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return (va->va_end - va->va_start);
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}
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static __always_inline unsigned long
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get_subtree_max_size(struct rb_node *node)
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{
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struct vmap_area *va;
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va = rb_entry_safe(node, struct vmap_area, rb_node);
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return va ? va->subtree_max_size : 0;
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}
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/*
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* Gets called when remove the node and rotate.
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*/
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static __always_inline unsigned long
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compute_subtree_max_size(struct vmap_area *va)
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{
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return max3(va_size(va),
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get_subtree_max_size(va->rb_node.rb_left),
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get_subtree_max_size(va->rb_node.rb_right));
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}
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|
|
RB_DECLARE_CALLBACKS_MAX(static, free_vmap_area_rb_augment_cb,
|
|
struct vmap_area, rb_node, unsigned long, subtree_max_size, va_size)
|
|
|
|
static void purge_vmap_area_lazy(void);
|
|
static BLOCKING_NOTIFIER_HEAD(vmap_notify_list);
|
|
static unsigned long lazy_max_pages(void);
|
|
|
|
static atomic_long_t nr_vmalloc_pages;
|
|
|
|
unsigned long vmalloc_nr_pages(void)
|
|
{
|
|
return atomic_long_read(&nr_vmalloc_pages);
|
|
}
|
|
|
|
static struct vmap_area *__find_vmap_area(unsigned long addr)
|
|
{
|
|
struct rb_node *n = vmap_area_root.rb_node;
|
|
|
|
while (n) {
|
|
struct vmap_area *va;
|
|
|
|
va = rb_entry(n, struct vmap_area, rb_node);
|
|
if (addr < va->va_start)
|
|
n = n->rb_left;
|
|
else if (addr >= va->va_end)
|
|
n = n->rb_right;
|
|
else
|
|
return va;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* This function returns back addresses of parent node
|
|
* and its left or right link for further processing.
|
|
*
|
|
* Otherwise NULL is returned. In that case all further
|
|
* steps regarding inserting of conflicting overlap range
|
|
* have to be declined and actually considered as a bug.
|
|
*/
|
|
static __always_inline struct rb_node **
|
|
find_va_links(struct vmap_area *va,
|
|
struct rb_root *root, struct rb_node *from,
|
|
struct rb_node **parent)
|
|
{
|
|
struct vmap_area *tmp_va;
|
|
struct rb_node **link;
|
|
|
|
if (root) {
|
|
link = &root->rb_node;
|
|
if (unlikely(!*link)) {
|
|
*parent = NULL;
|
|
return link;
|
|
}
|
|
} else {
|
|
link = &from;
|
|
}
|
|
|
|
/*
|
|
* Go to the bottom of the tree. When we hit the last point
|
|
* we end up with parent rb_node and correct direction, i name
|
|
* it link, where the new va->rb_node will be attached to.
|
|
*/
|
|
do {
|
|
tmp_va = rb_entry(*link, struct vmap_area, rb_node);
|
|
|
|
/*
|
|
* During the traversal we also do some sanity check.
|
|
* Trigger the BUG() if there are sides(left/right)
|
|
* or full overlaps.
|
|
*/
|
|
if (va->va_start < tmp_va->va_end &&
|
|
va->va_end <= tmp_va->va_start)
|
|
link = &(*link)->rb_left;
|
|
else if (va->va_end > tmp_va->va_start &&
|
|
va->va_start >= tmp_va->va_end)
|
|
link = &(*link)->rb_right;
|
|
else {
|
|
WARN(1, "vmalloc bug: 0x%lx-0x%lx overlaps with 0x%lx-0x%lx\n",
|
|
va->va_start, va->va_end, tmp_va->va_start, tmp_va->va_end);
|
|
|
|
return NULL;
|
|
}
|
|
} while (*link);
|
|
|
|
*parent = &tmp_va->rb_node;
|
|
return link;
|
|
}
|
|
|
|
static __always_inline struct list_head *
|
|
get_va_next_sibling(struct rb_node *parent, struct rb_node **link)
|
|
{
|
|
struct list_head *list;
|
|
|
|
if (unlikely(!parent))
|
|
/*
|
|
* The red-black tree where we try to find VA neighbors
|
|
* before merging or inserting is empty, i.e. it means
|
|
* there is no free vmap space. Normally it does not
|
|
* happen but we handle this case anyway.
|
|
*/
|
|
return NULL;
|
|
|
|
list = &rb_entry(parent, struct vmap_area, rb_node)->list;
|
|
return (&parent->rb_right == link ? list->next : list);
|
|
}
|
|
|
|
static __always_inline void
|
|
link_va(struct vmap_area *va, struct rb_root *root,
|
|
struct rb_node *parent, struct rb_node **link, struct list_head *head)
|
|
{
|
|
/*
|
|
* VA is still not in the list, but we can
|
|
* identify its future previous list_head node.
|
|
*/
|
|
if (likely(parent)) {
|
|
head = &rb_entry(parent, struct vmap_area, rb_node)->list;
|
|
if (&parent->rb_right != link)
|
|
head = head->prev;
|
|
}
|
|
|
|
/* Insert to the rb-tree */
|
|
rb_link_node(&va->rb_node, parent, link);
|
|
if (root == &free_vmap_area_root) {
|
|
/*
|
|
* Some explanation here. Just perform simple insertion
|
|
* to the tree. We do not set va->subtree_max_size to
|
|
* its current size before calling rb_insert_augmented().
|
|
* It is because of we populate the tree from the bottom
|
|
* to parent levels when the node _is_ in the tree.
|
|
*
|
|
* Therefore we set subtree_max_size to zero after insertion,
|
|
* to let __augment_tree_propagate_from() puts everything to
|
|
* the correct order later on.
|
|
*/
|
|
rb_insert_augmented(&va->rb_node,
|
|
root, &free_vmap_area_rb_augment_cb);
|
|
va->subtree_max_size = 0;
|
|
} else {
|
|
rb_insert_color(&va->rb_node, root);
|
|
}
|
|
|
|
/* Address-sort this list */
|
|
list_add(&va->list, head);
|
|
}
|
|
|
|
static __always_inline void
|
|
unlink_va(struct vmap_area *va, struct rb_root *root)
|
|
{
|
|
if (WARN_ON(RB_EMPTY_NODE(&va->rb_node)))
|
|
return;
|
|
|
|
if (root == &free_vmap_area_root)
|
|
rb_erase_augmented(&va->rb_node,
|
|
root, &free_vmap_area_rb_augment_cb);
|
|
else
|
|
rb_erase(&va->rb_node, root);
|
|
|
|
list_del(&va->list);
|
|
RB_CLEAR_NODE(&va->rb_node);
|
|
}
|
|
|
|
#if DEBUG_AUGMENT_PROPAGATE_CHECK
|
|
static void
|
|
augment_tree_propagate_check(void)
|
|
{
|
|
struct vmap_area *va;
|
|
unsigned long computed_size;
|
|
|
|
list_for_each_entry(va, &free_vmap_area_list, list) {
|
|
computed_size = compute_subtree_max_size(va);
|
|
if (computed_size != va->subtree_max_size)
|
|
pr_emerg("tree is corrupted: %lu, %lu\n",
|
|
va_size(va), va->subtree_max_size);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* This function populates subtree_max_size from bottom to upper
|
|
* levels starting from VA point. The propagation must be done
|
|
* when VA size is modified by changing its va_start/va_end. Or
|
|
* in case of newly inserting of VA to the tree.
|
|
*
|
|
* It means that __augment_tree_propagate_from() must be called:
|
|
* - After VA has been inserted to the tree(free path);
|
|
* - After VA has been shrunk(allocation path);
|
|
* - After VA has been increased(merging path).
|
|
*
|
|
* Please note that, it does not mean that upper parent nodes
|
|
* and their subtree_max_size are recalculated all the time up
|
|
* to the root node.
|
|
*
|
|
* 4--8
|
|
* /\
|
|
* / \
|
|
* / \
|
|
* 2--2 8--8
|
|
*
|
|
* For example if we modify the node 4, shrinking it to 2, then
|
|
* no any modification is required. If we shrink the node 2 to 1
|
|
* its subtree_max_size is updated only, and set to 1. If we shrink
|
|
* the node 8 to 6, then its subtree_max_size is set to 6 and parent
|
|
* node becomes 4--6.
|
|
*/
|
|
static __always_inline void
|
|
augment_tree_propagate_from(struct vmap_area *va)
|
|
{
|
|
/*
|
|
* Populate the tree from bottom towards the root until
|
|
* the calculated maximum available size of checked node
|
|
* is equal to its current one.
|
|
*/
|
|
free_vmap_area_rb_augment_cb_propagate(&va->rb_node, NULL);
|
|
|
|
#if DEBUG_AUGMENT_PROPAGATE_CHECK
|
|
augment_tree_propagate_check();
|
|
#endif
|
|
}
|
|
|
|
static void
|
|
insert_vmap_area(struct vmap_area *va,
|
|
struct rb_root *root, struct list_head *head)
|
|
{
|
|
struct rb_node **link;
|
|
struct rb_node *parent;
|
|
|
|
link = find_va_links(va, root, NULL, &parent);
|
|
if (link)
|
|
link_va(va, root, parent, link, head);
|
|
}
|
|
|
|
static void
|
|
insert_vmap_area_augment(struct vmap_area *va,
|
|
struct rb_node *from, struct rb_root *root,
|
|
struct list_head *head)
|
|
{
|
|
struct rb_node **link;
|
|
struct rb_node *parent;
|
|
|
|
if (from)
|
|
link = find_va_links(va, NULL, from, &parent);
|
|
else
|
|
link = find_va_links(va, root, NULL, &parent);
|
|
|
|
if (link) {
|
|
link_va(va, root, parent, link, head);
|
|
augment_tree_propagate_from(va);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Merge de-allocated chunk of VA memory with previous
|
|
* and next free blocks. If coalesce is not done a new
|
|
* free area is inserted. If VA has been merged, it is
|
|
* freed.
|
|
*
|
|
* Please note, it can return NULL in case of overlap
|
|
* ranges, followed by WARN() report. Despite it is a
|
|
* buggy behaviour, a system can be alive and keep
|
|
* ongoing.
|
|
*/
|
|
static __always_inline struct vmap_area *
|
|
merge_or_add_vmap_area(struct vmap_area *va,
|
|
struct rb_root *root, struct list_head *head)
|
|
{
|
|
struct vmap_area *sibling;
|
|
struct list_head *next;
|
|
struct rb_node **link;
|
|
struct rb_node *parent;
|
|
bool merged = false;
|
|
|
|
/*
|
|
* Find a place in the tree where VA potentially will be
|
|
* inserted, unless it is merged with its sibling/siblings.
|
|
*/
|
|
link = find_va_links(va, root, NULL, &parent);
|
|
if (!link)
|
|
return NULL;
|
|
|
|
/*
|
|
* Get next node of VA to check if merging can be done.
|
|
*/
|
|
next = get_va_next_sibling(parent, link);
|
|
if (unlikely(next == NULL))
|
|
goto insert;
|
|
|
|
/*
|
|
* start end
|
|
* | |
|
|
* |<------VA------>|<-----Next----->|
|
|
* | |
|
|
* start end
|
|
*/
|
|
if (next != head) {
|
|
sibling = list_entry(next, struct vmap_area, list);
|
|
if (sibling->va_start == va->va_end) {
|
|
sibling->va_start = va->va_start;
|
|
|
|
/* Free vmap_area object. */
|
|
kmem_cache_free(vmap_area_cachep, va);
|
|
|
|
/* Point to the new merged area. */
|
|
va = sibling;
|
|
merged = true;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* start end
|
|
* | |
|
|
* |<-----Prev----->|<------VA------>|
|
|
* | |
|
|
* start end
|
|
*/
|
|
if (next->prev != head) {
|
|
sibling = list_entry(next->prev, struct vmap_area, list);
|
|
if (sibling->va_end == va->va_start) {
|
|
/*
|
|
* If both neighbors are coalesced, it is important
|
|
* to unlink the "next" node first, followed by merging
|
|
* with "previous" one. Otherwise the tree might not be
|
|
* fully populated if a sibling's augmented value is
|
|
* "normalized" because of rotation operations.
|
|
*/
|
|
if (merged)
|
|
unlink_va(va, root);
|
|
|
|
sibling->va_end = va->va_end;
|
|
|
|
/* Free vmap_area object. */
|
|
kmem_cache_free(vmap_area_cachep, va);
|
|
|
|
/* Point to the new merged area. */
|
|
va = sibling;
|
|
merged = true;
|
|
}
|
|
}
|
|
|
|
insert:
|
|
if (!merged)
|
|
link_va(va, root, parent, link, head);
|
|
|
|
return va;
|
|
}
|
|
|
|
static __always_inline struct vmap_area *
|
|
merge_or_add_vmap_area_augment(struct vmap_area *va,
|
|
struct rb_root *root, struct list_head *head)
|
|
{
|
|
va = merge_or_add_vmap_area(va, root, head);
|
|
if (va)
|
|
augment_tree_propagate_from(va);
|
|
|
|
return va;
|
|
}
|
|
|
|
static __always_inline bool
|
|
is_within_this_va(struct vmap_area *va, unsigned long size,
|
|
unsigned long align, unsigned long vstart)
|
|
{
|
|
unsigned long nva_start_addr;
|
|
|
|
if (va->va_start > vstart)
|
|
nva_start_addr = ALIGN(va->va_start, align);
|
|
else
|
|
nva_start_addr = ALIGN(vstart, align);
|
|
|
|
/* Can be overflowed due to big size or alignment. */
|
|
if (nva_start_addr + size < nva_start_addr ||
|
|
nva_start_addr < vstart)
|
|
return false;
|
|
|
|
return (nva_start_addr + size <= va->va_end);
|
|
}
|
|
|
|
/*
|
|
* Find the first free block(lowest start address) in the tree,
|
|
* that will accomplish the request corresponding to passing
|
|
* parameters.
|
|
*/
|
|
static __always_inline struct vmap_area *
|
|
find_vmap_lowest_match(unsigned long size,
|
|
unsigned long align, unsigned long vstart)
|
|
{
|
|
struct vmap_area *va;
|
|
struct rb_node *node;
|
|
unsigned long length;
|
|
|
|
/* Start from the root. */
|
|
node = free_vmap_area_root.rb_node;
|
|
|
|
/* Adjust the search size for alignment overhead. */
|
|
length = size + align - 1;
|
|
|
|
while (node) {
|
|
va = rb_entry(node, struct vmap_area, rb_node);
|
|
|
|
if (get_subtree_max_size(node->rb_left) >= length &&
|
|
vstart < va->va_start) {
|
|
node = node->rb_left;
|
|
} else {
|
|
if (is_within_this_va(va, size, align, vstart))
|
|
return va;
|
|
|
|
/*
|
|
* Does not make sense to go deeper towards the right
|
|
* sub-tree if it does not have a free block that is
|
|
* equal or bigger to the requested search length.
|
|
*/
|
|
if (get_subtree_max_size(node->rb_right) >= length) {
|
|
node = node->rb_right;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* OK. We roll back and find the first right sub-tree,
|
|
* that will satisfy the search criteria. It can happen
|
|
* only once due to "vstart" restriction.
|
|
*/
|
|
while ((node = rb_parent(node))) {
|
|
va = rb_entry(node, struct vmap_area, rb_node);
|
|
if (is_within_this_va(va, size, align, vstart))
|
|
return va;
|
|
|
|
if (get_subtree_max_size(node->rb_right) >= length &&
|
|
vstart <= va->va_start) {
|
|
node = node->rb_right;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
#if DEBUG_AUGMENT_LOWEST_MATCH_CHECK
|
|
#include <linux/random.h>
|
|
|
|
static struct vmap_area *
|
|
find_vmap_lowest_linear_match(unsigned long size,
|
|
unsigned long align, unsigned long vstart)
|
|
{
|
|
struct vmap_area *va;
|
|
|
|
list_for_each_entry(va, &free_vmap_area_list, list) {
|
|
if (!is_within_this_va(va, size, align, vstart))
|
|
continue;
|
|
|
|
return va;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void
|
|
find_vmap_lowest_match_check(unsigned long size)
|
|
{
|
|
struct vmap_area *va_1, *va_2;
|
|
unsigned long vstart;
|
|
unsigned int rnd;
|
|
|
|
get_random_bytes(&rnd, sizeof(rnd));
|
|
vstart = VMALLOC_START + rnd;
|
|
|
|
va_1 = find_vmap_lowest_match(size, 1, vstart);
|
|
va_2 = find_vmap_lowest_linear_match(size, 1, vstart);
|
|
|
|
if (va_1 != va_2)
|
|
pr_emerg("not lowest: t: 0x%p, l: 0x%p, v: 0x%lx\n",
|
|
va_1, va_2, vstart);
|
|
}
|
|
#endif
|
|
|
|
enum fit_type {
|
|
NOTHING_FIT = 0,
|
|
FL_FIT_TYPE = 1, /* full fit */
|
|
LE_FIT_TYPE = 2, /* left edge fit */
|
|
RE_FIT_TYPE = 3, /* right edge fit */
|
|
NE_FIT_TYPE = 4 /* no edge fit */
|
|
};
|
|
|
|
static __always_inline enum fit_type
|
|
classify_va_fit_type(struct vmap_area *va,
|
|
unsigned long nva_start_addr, unsigned long size)
|
|
{
|
|
enum fit_type type;
|
|
|
|
/* Check if it is within VA. */
|
|
if (nva_start_addr < va->va_start ||
|
|
nva_start_addr + size > va->va_end)
|
|
return NOTHING_FIT;
|
|
|
|
/* Now classify. */
|
|
if (va->va_start == nva_start_addr) {
|
|
if (va->va_end == nva_start_addr + size)
|
|
type = FL_FIT_TYPE;
|
|
else
|
|
type = LE_FIT_TYPE;
|
|
} else if (va->va_end == nva_start_addr + size) {
|
|
type = RE_FIT_TYPE;
|
|
} else {
|
|
type = NE_FIT_TYPE;
|
|
}
|
|
|
|
return type;
|
|
}
|
|
|
|
static __always_inline int
|
|
adjust_va_to_fit_type(struct vmap_area *va,
|
|
unsigned long nva_start_addr, unsigned long size,
|
|
enum fit_type type)
|
|
{
|
|
struct vmap_area *lva = NULL;
|
|
|
|
if (type == FL_FIT_TYPE) {
|
|
/*
|
|
* No need to split VA, it fully fits.
|
|
*
|
|
* | |
|
|
* V NVA V
|
|
* |---------------|
|
|
*/
|
|
unlink_va(va, &free_vmap_area_root);
|
|
kmem_cache_free(vmap_area_cachep, va);
|
|
} else if (type == LE_FIT_TYPE) {
|
|
/*
|
|
* Split left edge of fit VA.
|
|
*
|
|
* | |
|
|
* V NVA V R
|
|
* |-------|-------|
|
|
*/
|
|
va->va_start += size;
|
|
} else if (type == RE_FIT_TYPE) {
|
|
/*
|
|
* Split right edge of fit VA.
|
|
*
|
|
* | |
|
|
* L V NVA V
|
|
* |-------|-------|
|
|
*/
|
|
va->va_end = nva_start_addr;
|
|
} else if (type == NE_FIT_TYPE) {
|
|
/*
|
|
* Split no edge of fit VA.
|
|
*
|
|
* | |
|
|
* L V NVA V R
|
|
* |---|-------|---|
|
|
*/
|
|
lva = __this_cpu_xchg(ne_fit_preload_node, NULL);
|
|
if (unlikely(!lva)) {
|
|
/*
|
|
* For percpu allocator we do not do any pre-allocation
|
|
* and leave it as it is. The reason is it most likely
|
|
* never ends up with NE_FIT_TYPE splitting. In case of
|
|
* percpu allocations offsets and sizes are aligned to
|
|
* fixed align request, i.e. RE_FIT_TYPE and FL_FIT_TYPE
|
|
* are its main fitting cases.
|
|
*
|
|
* There are a few exceptions though, as an example it is
|
|
* a first allocation (early boot up) when we have "one"
|
|
* big free space that has to be split.
|
|
*
|
|
* Also we can hit this path in case of regular "vmap"
|
|
* allocations, if "this" current CPU was not preloaded.
|
|
* See the comment in alloc_vmap_area() why. If so, then
|
|
* GFP_NOWAIT is used instead to get an extra object for
|
|
* split purpose. That is rare and most time does not
|
|
* occur.
|
|
*
|
|
* What happens if an allocation gets failed. Basically,
|
|
* an "overflow" path is triggered to purge lazily freed
|
|
* areas to free some memory, then, the "retry" path is
|
|
* triggered to repeat one more time. See more details
|
|
* in alloc_vmap_area() function.
|
|
*/
|
|
lva = kmem_cache_alloc(vmap_area_cachep, GFP_NOWAIT);
|
|
if (!lva)
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Build the remainder.
|
|
*/
|
|
lva->va_start = va->va_start;
|
|
lva->va_end = nva_start_addr;
|
|
|
|
/*
|
|
* Shrink this VA to remaining size.
|
|
*/
|
|
va->va_start = nva_start_addr + size;
|
|
} else {
|
|
return -1;
|
|
}
|
|
|
|
if (type != FL_FIT_TYPE) {
|
|
augment_tree_propagate_from(va);
|
|
|
|
if (lva) /* type == NE_FIT_TYPE */
|
|
insert_vmap_area_augment(lva, &va->rb_node,
|
|
&free_vmap_area_root, &free_vmap_area_list);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Returns a start address of the newly allocated area, if success.
|
|
* Otherwise a vend is returned that indicates failure.
|
|
*/
|
|
static __always_inline unsigned long
|
|
__alloc_vmap_area(unsigned long size, unsigned long align,
|
|
unsigned long vstart, unsigned long vend)
|
|
{
|
|
unsigned long nva_start_addr;
|
|
struct vmap_area *va;
|
|
enum fit_type type;
|
|
int ret;
|
|
|
|
va = find_vmap_lowest_match(size, align, vstart);
|
|
if (unlikely(!va))
|
|
return vend;
|
|
|
|
if (va->va_start > vstart)
|
|
nva_start_addr = ALIGN(va->va_start, align);
|
|
else
|
|
nva_start_addr = ALIGN(vstart, align);
|
|
|
|
/* Check the "vend" restriction. */
|
|
if (nva_start_addr + size > vend)
|
|
return vend;
|
|
|
|
/* Classify what we have found. */
|
|
type = classify_va_fit_type(va, nva_start_addr, size);
|
|
if (WARN_ON_ONCE(type == NOTHING_FIT))
|
|
return vend;
|
|
|
|
/* Update the free vmap_area. */
|
|
ret = adjust_va_to_fit_type(va, nva_start_addr, size, type);
|
|
if (ret)
|
|
return vend;
|
|
|
|
#if DEBUG_AUGMENT_LOWEST_MATCH_CHECK
|
|
find_vmap_lowest_match_check(size);
|
|
#endif
|
|
|
|
return nva_start_addr;
|
|
}
|
|
|
|
/*
|
|
* Free a region of KVA allocated by alloc_vmap_area
|
|
*/
|
|
static void free_vmap_area(struct vmap_area *va)
|
|
{
|
|
/*
|
|
* Remove from the busy tree/list.
|
|
*/
|
|
spin_lock(&vmap_area_lock);
|
|
unlink_va(va, &vmap_area_root);
|
|
spin_unlock(&vmap_area_lock);
|
|
|
|
/*
|
|
* Insert/Merge it back to the free tree/list.
|
|
*/
|
|
spin_lock(&free_vmap_area_lock);
|
|
merge_or_add_vmap_area_augment(va, &free_vmap_area_root, &free_vmap_area_list);
|
|
spin_unlock(&free_vmap_area_lock);
|
|
}
|
|
|
|
/*
|
|
* Allocate a region of KVA of the specified size and alignment, within the
|
|
* vstart and vend.
|
|
*/
|
|
static struct vmap_area *alloc_vmap_area(unsigned long size,
|
|
unsigned long align,
|
|
unsigned long vstart, unsigned long vend,
|
|
int node, gfp_t gfp_mask)
|
|
{
|
|
struct vmap_area *va, *pva;
|
|
unsigned long addr;
|
|
int purged = 0;
|
|
int ret;
|
|
|
|
BUG_ON(!size);
|
|
BUG_ON(offset_in_page(size));
|
|
BUG_ON(!is_power_of_2(align));
|
|
|
|
if (unlikely(!vmap_initialized))
|
|
return ERR_PTR(-EBUSY);
|
|
|
|
might_sleep();
|
|
gfp_mask = gfp_mask & GFP_RECLAIM_MASK;
|
|
|
|
va = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
|
|
if (unlikely(!va))
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
/*
|
|
* Only scan the relevant parts containing pointers to other objects
|
|
* to avoid false negatives.
|
|
*/
|
|
kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
|
|
|
|
retry:
|
|
/*
|
|
* Preload this CPU with one extra vmap_area object. It is used
|
|
* when fit type of free area is NE_FIT_TYPE. Please note, it
|
|
* does not guarantee that an allocation occurs on a CPU that
|
|
* is preloaded, instead we minimize the case when it is not.
|
|
* It can happen because of cpu migration, because there is a
|
|
* race until the below spinlock is taken.
|
|
*
|
|
* The preload is done in non-atomic context, thus it allows us
|
|
* to use more permissive allocation masks to be more stable under
|
|
* low memory condition and high memory pressure. In rare case,
|
|
* if not preloaded, GFP_NOWAIT is used.
|
|
*
|
|
* Set "pva" to NULL here, because of "retry" path.
|
|
*/
|
|
pva = NULL;
|
|
|
|
if (!this_cpu_read(ne_fit_preload_node))
|
|
/*
|
|
* Even if it fails we do not really care about that.
|
|
* Just proceed as it is. If needed "overflow" path
|
|
* will refill the cache we allocate from.
|
|
*/
|
|
pva = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
|
|
|
|
spin_lock(&free_vmap_area_lock);
|
|
|
|
if (pva && __this_cpu_cmpxchg(ne_fit_preload_node, NULL, pva))
|
|
kmem_cache_free(vmap_area_cachep, pva);
|
|
|
|
/*
|
|
* If an allocation fails, the "vend" address is
|
|
* returned. Therefore trigger the overflow path.
|
|
*/
|
|
addr = __alloc_vmap_area(size, align, vstart, vend);
|
|
spin_unlock(&free_vmap_area_lock);
|
|
|
|
if (unlikely(addr == vend))
|
|
goto overflow;
|
|
|
|
va->va_start = addr;
|
|
va->va_end = addr + size;
|
|
va->vm = NULL;
|
|
|
|
|
|
spin_lock(&vmap_area_lock);
|
|
insert_vmap_area(va, &vmap_area_root, &vmap_area_list);
|
|
spin_unlock(&vmap_area_lock);
|
|
|
|
BUG_ON(!IS_ALIGNED(va->va_start, align));
|
|
BUG_ON(va->va_start < vstart);
|
|
BUG_ON(va->va_end > vend);
|
|
|
|
ret = kasan_populate_vmalloc(addr, size);
|
|
if (ret) {
|
|
free_vmap_area(va);
|
|
return ERR_PTR(ret);
|
|
}
|
|
|
|
return va;
|
|
|
|
overflow:
|
|
if (!purged) {
|
|
purge_vmap_area_lazy();
|
|
purged = 1;
|
|
goto retry;
|
|
}
|
|
|
|
if (gfpflags_allow_blocking(gfp_mask)) {
|
|
unsigned long freed = 0;
|
|
blocking_notifier_call_chain(&vmap_notify_list, 0, &freed);
|
|
if (freed > 0) {
|
|
purged = 0;
|
|
goto retry;
|
|
}
|
|
}
|
|
|
|
if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit())
|
|
pr_warn("vmap allocation for size %lu failed: use vmalloc=<size> to increase size\n",
|
|
size);
|
|
|
|
kmem_cache_free(vmap_area_cachep, va);
|
|
return ERR_PTR(-EBUSY);
|
|
}
|
|
|
|
int register_vmap_purge_notifier(struct notifier_block *nb)
|
|
{
|
|
return blocking_notifier_chain_register(&vmap_notify_list, nb);
|
|
}
|
|
EXPORT_SYMBOL_GPL(register_vmap_purge_notifier);
|
|
|
|
int unregister_vmap_purge_notifier(struct notifier_block *nb)
|
|
{
|
|
return blocking_notifier_chain_unregister(&vmap_notify_list, nb);
|
|
}
|
|
EXPORT_SYMBOL_GPL(unregister_vmap_purge_notifier);
|
|
|
|
/*
|
|
* lazy_max_pages is the maximum amount of virtual address space we gather up
|
|
* before attempting to purge with a TLB flush.
|
|
*
|
|
* There is a tradeoff here: a larger number will cover more kernel page tables
|
|
* and take slightly longer to purge, but it will linearly reduce the number of
|
|
* global TLB flushes that must be performed. It would seem natural to scale
|
|
* this number up linearly with the number of CPUs (because vmapping activity
|
|
* could also scale linearly with the number of CPUs), however it is likely
|
|
* that in practice, workloads might be constrained in other ways that mean
|
|
* vmap activity will not scale linearly with CPUs. Also, I want to be
|
|
* conservative and not introduce a big latency on huge systems, so go with
|
|
* a less aggressive log scale. It will still be an improvement over the old
|
|
* code, and it will be simple to change the scale factor if we find that it
|
|
* becomes a problem on bigger systems.
|
|
*/
|
|
static unsigned long lazy_max_pages(void)
|
|
{
|
|
unsigned int log;
|
|
|
|
log = fls(num_online_cpus());
|
|
|
|
return log * (32UL * 1024 * 1024 / PAGE_SIZE);
|
|
}
|
|
|
|
static atomic_long_t vmap_lazy_nr = ATOMIC_LONG_INIT(0);
|
|
|
|
/*
|
|
* Serialize vmap purging. There is no actual criticial section protected
|
|
* by this look, but we want to avoid concurrent calls for performance
|
|
* reasons and to make the pcpu_get_vm_areas more deterministic.
|
|
*/
|
|
static DEFINE_MUTEX(vmap_purge_lock);
|
|
|
|
/* for per-CPU blocks */
|
|
static void purge_fragmented_blocks_allcpus(void);
|
|
|
|
/*
|
|
* called before a call to iounmap() if the caller wants vm_area_struct's
|
|
* immediately freed.
|
|
*/
|
|
void set_iounmap_nonlazy(void)
|
|
{
|
|
atomic_long_set(&vmap_lazy_nr, lazy_max_pages()+1);
|
|
}
|
|
|
|
/*
|
|
* Purges all lazily-freed vmap areas.
|
|
*/
|
|
static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end)
|
|
{
|
|
unsigned long resched_threshold;
|
|
struct list_head local_pure_list;
|
|
struct vmap_area *va, *n_va;
|
|
|
|
lockdep_assert_held(&vmap_purge_lock);
|
|
|
|
spin_lock(&purge_vmap_area_lock);
|
|
purge_vmap_area_root = RB_ROOT;
|
|
list_replace_init(&purge_vmap_area_list, &local_pure_list);
|
|
spin_unlock(&purge_vmap_area_lock);
|
|
|
|
if (unlikely(list_empty(&local_pure_list)))
|
|
return false;
|
|
|
|
start = min(start,
|
|
list_first_entry(&local_pure_list,
|
|
struct vmap_area, list)->va_start);
|
|
|
|
end = max(end,
|
|
list_last_entry(&local_pure_list,
|
|
struct vmap_area, list)->va_end);
|
|
|
|
flush_tlb_kernel_range(start, end);
|
|
resched_threshold = lazy_max_pages() << 1;
|
|
|
|
spin_lock(&free_vmap_area_lock);
|
|
list_for_each_entry_safe(va, n_va, &local_pure_list, list) {
|
|
unsigned long nr = (va->va_end - va->va_start) >> PAGE_SHIFT;
|
|
unsigned long orig_start = va->va_start;
|
|
unsigned long orig_end = va->va_end;
|
|
|
|
/*
|
|
* Finally insert or merge lazily-freed area. It is
|
|
* detached and there is no need to "unlink" it from
|
|
* anything.
|
|
*/
|
|
va = merge_or_add_vmap_area_augment(va, &free_vmap_area_root,
|
|
&free_vmap_area_list);
|
|
|
|
if (!va)
|
|
continue;
|
|
|
|
if (is_vmalloc_or_module_addr((void *)orig_start))
|
|
kasan_release_vmalloc(orig_start, orig_end,
|
|
va->va_start, va->va_end);
|
|
|
|
atomic_long_sub(nr, &vmap_lazy_nr);
|
|
|
|
if (atomic_long_read(&vmap_lazy_nr) < resched_threshold)
|
|
cond_resched_lock(&free_vmap_area_lock);
|
|
}
|
|
spin_unlock(&free_vmap_area_lock);
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Kick off a purge of the outstanding lazy areas. Don't bother if somebody
|
|
* is already purging.
|
|
*/
|
|
static void try_purge_vmap_area_lazy(void)
|
|
{
|
|
if (mutex_trylock(&vmap_purge_lock)) {
|
|
__purge_vmap_area_lazy(ULONG_MAX, 0);
|
|
mutex_unlock(&vmap_purge_lock);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Kick off a purge of the outstanding lazy areas.
|
|
*/
|
|
static void purge_vmap_area_lazy(void)
|
|
{
|
|
mutex_lock(&vmap_purge_lock);
|
|
purge_fragmented_blocks_allcpus();
|
|
__purge_vmap_area_lazy(ULONG_MAX, 0);
|
|
mutex_unlock(&vmap_purge_lock);
|
|
}
|
|
|
|
/*
|
|
* Free a vmap area, caller ensuring that the area has been unmapped
|
|
* and flush_cache_vunmap had been called for the correct range
|
|
* previously.
|
|
*/
|
|
static void free_vmap_area_noflush(struct vmap_area *va)
|
|
{
|
|
unsigned long nr_lazy;
|
|
|
|
spin_lock(&vmap_area_lock);
|
|
unlink_va(va, &vmap_area_root);
|
|
spin_unlock(&vmap_area_lock);
|
|
|
|
nr_lazy = atomic_long_add_return((va->va_end - va->va_start) >>
|
|
PAGE_SHIFT, &vmap_lazy_nr);
|
|
|
|
/*
|
|
* Merge or place it to the purge tree/list.
|
|
*/
|
|
spin_lock(&purge_vmap_area_lock);
|
|
merge_or_add_vmap_area(va,
|
|
&purge_vmap_area_root, &purge_vmap_area_list);
|
|
spin_unlock(&purge_vmap_area_lock);
|
|
|
|
/* After this point, we may free va at any time */
|
|
if (unlikely(nr_lazy > lazy_max_pages()))
|
|
try_purge_vmap_area_lazy();
|
|
}
|
|
|
|
/*
|
|
* Free and unmap a vmap area
|
|
*/
|
|
static void free_unmap_vmap_area(struct vmap_area *va)
|
|
{
|
|
flush_cache_vunmap(va->va_start, va->va_end);
|
|
unmap_kernel_range_noflush(va->va_start, va->va_end - va->va_start);
|
|
if (debug_pagealloc_enabled_static())
|
|
flush_tlb_kernel_range(va->va_start, va->va_end);
|
|
|
|
free_vmap_area_noflush(va);
|
|
}
|
|
|
|
static struct vmap_area *find_vmap_area(unsigned long addr)
|
|
{
|
|
struct vmap_area *va;
|
|
|
|
spin_lock(&vmap_area_lock);
|
|
va = __find_vmap_area(addr);
|
|
spin_unlock(&vmap_area_lock);
|
|
|
|
return va;
|
|
}
|
|
|
|
/*** Per cpu kva allocator ***/
|
|
|
|
/*
|
|
* vmap space is limited especially on 32 bit architectures. Ensure there is
|
|
* room for at least 16 percpu vmap blocks per CPU.
|
|
*/
|
|
/*
|
|
* If we had a constant VMALLOC_START and VMALLOC_END, we'd like to be able
|
|
* to #define VMALLOC_SPACE (VMALLOC_END-VMALLOC_START). Guess
|
|
* instead (we just need a rough idea)
|
|
*/
|
|
#if BITS_PER_LONG == 32
|
|
#define VMALLOC_SPACE (128UL*1024*1024)
|
|
#else
|
|
#define VMALLOC_SPACE (128UL*1024*1024*1024)
|
|
#endif
|
|
|
|
#define VMALLOC_PAGES (VMALLOC_SPACE / PAGE_SIZE)
|
|
#define VMAP_MAX_ALLOC BITS_PER_LONG /* 256K with 4K pages */
|
|
#define VMAP_BBMAP_BITS_MAX 1024 /* 4MB with 4K pages */
|
|
#define VMAP_BBMAP_BITS_MIN (VMAP_MAX_ALLOC*2)
|
|
#define VMAP_MIN(x, y) ((x) < (y) ? (x) : (y)) /* can't use min() */
|
|
#define VMAP_MAX(x, y) ((x) > (y) ? (x) : (y)) /* can't use max() */
|
|
#define VMAP_BBMAP_BITS \
|
|
VMAP_MIN(VMAP_BBMAP_BITS_MAX, \
|
|
VMAP_MAX(VMAP_BBMAP_BITS_MIN, \
|
|
VMALLOC_PAGES / roundup_pow_of_two(NR_CPUS) / 16))
|
|
|
|
#define VMAP_BLOCK_SIZE (VMAP_BBMAP_BITS * PAGE_SIZE)
|
|
|
|
struct vmap_block_queue {
|
|
spinlock_t lock;
|
|
struct list_head free;
|
|
};
|
|
|
|
struct vmap_block {
|
|
spinlock_t lock;
|
|
struct vmap_area *va;
|
|
unsigned long free, dirty;
|
|
unsigned long dirty_min, dirty_max; /*< dirty range */
|
|
struct list_head free_list;
|
|
struct rcu_head rcu_head;
|
|
struct list_head purge;
|
|
};
|
|
|
|
/* Queue of free and dirty vmap blocks, for allocation and flushing purposes */
|
|
static DEFINE_PER_CPU(struct vmap_block_queue, vmap_block_queue);
|
|
|
|
/*
|
|
* XArray of vmap blocks, indexed by address, to quickly find a vmap block
|
|
* in the free path. Could get rid of this if we change the API to return a
|
|
* "cookie" from alloc, to be passed to free. But no big deal yet.
|
|
*/
|
|
static DEFINE_XARRAY(vmap_blocks);
|
|
|
|
/*
|
|
* We should probably have a fallback mechanism to allocate virtual memory
|
|
* out of partially filled vmap blocks. However vmap block sizing should be
|
|
* fairly reasonable according to the vmalloc size, so it shouldn't be a
|
|
* big problem.
|
|
*/
|
|
|
|
static unsigned long addr_to_vb_idx(unsigned long addr)
|
|
{
|
|
addr -= VMALLOC_START & ~(VMAP_BLOCK_SIZE-1);
|
|
addr /= VMAP_BLOCK_SIZE;
|
|
return addr;
|
|
}
|
|
|
|
static void *vmap_block_vaddr(unsigned long va_start, unsigned long pages_off)
|
|
{
|
|
unsigned long addr;
|
|
|
|
addr = va_start + (pages_off << PAGE_SHIFT);
|
|
BUG_ON(addr_to_vb_idx(addr) != addr_to_vb_idx(va_start));
|
|
return (void *)addr;
|
|
}
|
|
|
|
/**
|
|
* new_vmap_block - allocates new vmap_block and occupies 2^order pages in this
|
|
* block. Of course pages number can't exceed VMAP_BBMAP_BITS
|
|
* @order: how many 2^order pages should be occupied in newly allocated block
|
|
* @gfp_mask: flags for the page level allocator
|
|
*
|
|
* Return: virtual address in a newly allocated block or ERR_PTR(-errno)
|
|
*/
|
|
static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
|
|
{
|
|
struct vmap_block_queue *vbq;
|
|
struct vmap_block *vb;
|
|
struct vmap_area *va;
|
|
unsigned long vb_idx;
|
|
int node, err;
|
|
void *vaddr;
|
|
|
|
node = numa_node_id();
|
|
|
|
vb = kmalloc_node(sizeof(struct vmap_block),
|
|
gfp_mask & GFP_RECLAIM_MASK, node);
|
|
if (unlikely(!vb))
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
va = alloc_vmap_area(VMAP_BLOCK_SIZE, VMAP_BLOCK_SIZE,
|
|
VMALLOC_START, VMALLOC_END,
|
|
node, gfp_mask);
|
|
if (IS_ERR(va)) {
|
|
kfree(vb);
|
|
return ERR_CAST(va);
|
|
}
|
|
|
|
vaddr = vmap_block_vaddr(va->va_start, 0);
|
|
spin_lock_init(&vb->lock);
|
|
vb->va = va;
|
|
/* At least something should be left free */
|
|
BUG_ON(VMAP_BBMAP_BITS <= (1UL << order));
|
|
vb->free = VMAP_BBMAP_BITS - (1UL << order);
|
|
vb->dirty = 0;
|
|
vb->dirty_min = VMAP_BBMAP_BITS;
|
|
vb->dirty_max = 0;
|
|
INIT_LIST_HEAD(&vb->free_list);
|
|
|
|
vb_idx = addr_to_vb_idx(va->va_start);
|
|
err = xa_insert(&vmap_blocks, vb_idx, vb, gfp_mask);
|
|
if (err) {
|
|
kfree(vb);
|
|
free_vmap_area(va);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
vbq = &get_cpu_var(vmap_block_queue);
|
|
spin_lock(&vbq->lock);
|
|
list_add_tail_rcu(&vb->free_list, &vbq->free);
|
|
spin_unlock(&vbq->lock);
|
|
put_cpu_var(vmap_block_queue);
|
|
|
|
return vaddr;
|
|
}
|
|
|
|
static void free_vmap_block(struct vmap_block *vb)
|
|
{
|
|
struct vmap_block *tmp;
|
|
|
|
tmp = xa_erase(&vmap_blocks, addr_to_vb_idx(vb->va->va_start));
|
|
BUG_ON(tmp != vb);
|
|
|
|
free_vmap_area_noflush(vb->va);
|
|
kfree_rcu(vb, rcu_head);
|
|
}
|
|
|
|
static void purge_fragmented_blocks(int cpu)
|
|
{
|
|
LIST_HEAD(purge);
|
|
struct vmap_block *vb;
|
|
struct vmap_block *n_vb;
|
|
struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(vb, &vbq->free, free_list) {
|
|
|
|
if (!(vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS))
|
|
continue;
|
|
|
|
spin_lock(&vb->lock);
|
|
if (vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS) {
|
|
vb->free = 0; /* prevent further allocs after releasing lock */
|
|
vb->dirty = VMAP_BBMAP_BITS; /* prevent purging it again */
|
|
vb->dirty_min = 0;
|
|
vb->dirty_max = VMAP_BBMAP_BITS;
|
|
spin_lock(&vbq->lock);
|
|
list_del_rcu(&vb->free_list);
|
|
spin_unlock(&vbq->lock);
|
|
spin_unlock(&vb->lock);
|
|
list_add_tail(&vb->purge, &purge);
|
|
} else
|
|
spin_unlock(&vb->lock);
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
list_for_each_entry_safe(vb, n_vb, &purge, purge) {
|
|
list_del(&vb->purge);
|
|
free_vmap_block(vb);
|
|
}
|
|
}
|
|
|
|
static void purge_fragmented_blocks_allcpus(void)
|
|
{
|
|
int cpu;
|
|
|
|
for_each_possible_cpu(cpu)
|
|
purge_fragmented_blocks(cpu);
|
|
}
|
|
|
|
static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
|
|
{
|
|
struct vmap_block_queue *vbq;
|
|
struct vmap_block *vb;
|
|
void *vaddr = NULL;
|
|
unsigned int order;
|
|
|
|
BUG_ON(offset_in_page(size));
|
|
BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
|
|
if (WARN_ON(size == 0)) {
|
|
/*
|
|
* Allocating 0 bytes isn't what caller wants since
|
|
* get_order(0) returns funny result. Just warn and terminate
|
|
* early.
|
|
*/
|
|
return NULL;
|
|
}
|
|
order = get_order(size);
|
|
|
|
rcu_read_lock();
|
|
vbq = &get_cpu_var(vmap_block_queue);
|
|
list_for_each_entry_rcu(vb, &vbq->free, free_list) {
|
|
unsigned long pages_off;
|
|
|
|
spin_lock(&vb->lock);
|
|
if (vb->free < (1UL << order)) {
|
|
spin_unlock(&vb->lock);
|
|
continue;
|
|
}
|
|
|
|
pages_off = VMAP_BBMAP_BITS - vb->free;
|
|
vaddr = vmap_block_vaddr(vb->va->va_start, pages_off);
|
|
vb->free -= 1UL << order;
|
|
if (vb->free == 0) {
|
|
spin_lock(&vbq->lock);
|
|
list_del_rcu(&vb->free_list);
|
|
spin_unlock(&vbq->lock);
|
|
}
|
|
|
|
spin_unlock(&vb->lock);
|
|
break;
|
|
}
|
|
|
|
put_cpu_var(vmap_block_queue);
|
|
rcu_read_unlock();
|
|
|
|
/* Allocate new block if nothing was found */
|
|
if (!vaddr)
|
|
vaddr = new_vmap_block(order, gfp_mask);
|
|
|
|
return vaddr;
|
|
}
|
|
|
|
static void vb_free(unsigned long addr, unsigned long size)
|
|
{
|
|
unsigned long offset;
|
|
unsigned int order;
|
|
struct vmap_block *vb;
|
|
|
|
BUG_ON(offset_in_page(size));
|
|
BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
|
|
|
|
flush_cache_vunmap(addr, addr + size);
|
|
|
|
order = get_order(size);
|
|
offset = (addr & (VMAP_BLOCK_SIZE - 1)) >> PAGE_SHIFT;
|
|
vb = xa_load(&vmap_blocks, addr_to_vb_idx(addr));
|
|
|
|
unmap_kernel_range_noflush(addr, size);
|
|
|
|
if (debug_pagealloc_enabled_static())
|
|
flush_tlb_kernel_range(addr, addr + size);
|
|
|
|
spin_lock(&vb->lock);
|
|
|
|
/* Expand dirty range */
|
|
vb->dirty_min = min(vb->dirty_min, offset);
|
|
vb->dirty_max = max(vb->dirty_max, offset + (1UL << order));
|
|
|
|
vb->dirty += 1UL << order;
|
|
if (vb->dirty == VMAP_BBMAP_BITS) {
|
|
BUG_ON(vb->free);
|
|
spin_unlock(&vb->lock);
|
|
free_vmap_block(vb);
|
|
} else
|
|
spin_unlock(&vb->lock);
|
|
}
|
|
|
|
static void _vm_unmap_aliases(unsigned long start, unsigned long end, int flush)
|
|
{
|
|
int cpu;
|
|
|
|
if (unlikely(!vmap_initialized))
|
|
return;
|
|
|
|
might_sleep();
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
|
|
struct vmap_block *vb;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(vb, &vbq->free, free_list) {
|
|
spin_lock(&vb->lock);
|
|
if (vb->dirty) {
|
|
unsigned long va_start = vb->va->va_start;
|
|
unsigned long s, e;
|
|
|
|
s = va_start + (vb->dirty_min << PAGE_SHIFT);
|
|
e = va_start + (vb->dirty_max << PAGE_SHIFT);
|
|
|
|
start = min(s, start);
|
|
end = max(e, end);
|
|
|
|
flush = 1;
|
|
}
|
|
spin_unlock(&vb->lock);
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
mutex_lock(&vmap_purge_lock);
|
|
purge_fragmented_blocks_allcpus();
|
|
if (!__purge_vmap_area_lazy(start, end) && flush)
|
|
flush_tlb_kernel_range(start, end);
|
|
mutex_unlock(&vmap_purge_lock);
|
|
}
|
|
|
|
/**
|
|
* vm_unmap_aliases - unmap outstanding lazy aliases in the vmap layer
|
|
*
|
|
* The vmap/vmalloc layer lazily flushes kernel virtual mappings primarily
|
|
* to amortize TLB flushing overheads. What this means is that any page you
|
|
* have now, may, in a former life, have been mapped into kernel virtual
|
|
* address by the vmap layer and so there might be some CPUs with TLB entries
|
|
* still referencing that page (additional to the regular 1:1 kernel mapping).
|
|
*
|
|
* vm_unmap_aliases flushes all such lazy mappings. After it returns, we can
|
|
* be sure that none of the pages we have control over will have any aliases
|
|
* from the vmap layer.
|
|
*/
|
|
void vm_unmap_aliases(void)
|
|
{
|
|
unsigned long start = ULONG_MAX, end = 0;
|
|
int flush = 0;
|
|
|
|
_vm_unmap_aliases(start, end, flush);
|
|
}
|
|
EXPORT_SYMBOL_GPL(vm_unmap_aliases);
|
|
|
|
/**
|
|
* vm_unmap_ram - unmap linear kernel address space set up by vm_map_ram
|
|
* @mem: the pointer returned by vm_map_ram
|
|
* @count: the count passed to that vm_map_ram call (cannot unmap partial)
|
|
*/
|
|
void vm_unmap_ram(const void *mem, unsigned int count)
|
|
{
|
|
unsigned long size = (unsigned long)count << PAGE_SHIFT;
|
|
unsigned long addr = (unsigned long)mem;
|
|
struct vmap_area *va;
|
|
|
|
might_sleep();
|
|
BUG_ON(!addr);
|
|
BUG_ON(addr < VMALLOC_START);
|
|
BUG_ON(addr > VMALLOC_END);
|
|
BUG_ON(!PAGE_ALIGNED(addr));
|
|
|
|
kasan_poison_vmalloc(mem, size);
|
|
|
|
if (likely(count <= VMAP_MAX_ALLOC)) {
|
|
debug_check_no_locks_freed(mem, size);
|
|
vb_free(addr, size);
|
|
return;
|
|
}
|
|
|
|
va = find_vmap_area(addr);
|
|
BUG_ON(!va);
|
|
debug_check_no_locks_freed((void *)va->va_start,
|
|
(va->va_end - va->va_start));
|
|
free_unmap_vmap_area(va);
|
|
}
|
|
EXPORT_SYMBOL(vm_unmap_ram);
|
|
|
|
/**
|
|
* vm_map_ram - map pages linearly into kernel virtual address (vmalloc space)
|
|
* @pages: an array of pointers to the pages to be mapped
|
|
* @count: number of pages
|
|
* @node: prefer to allocate data structures on this node
|
|
*
|
|
* If you use this function for less than VMAP_MAX_ALLOC pages, it could be
|
|
* faster than vmap so it's good. But if you mix long-life and short-life
|
|
* objects with vm_map_ram(), it could consume lots of address space through
|
|
* fragmentation (especially on a 32bit machine). You could see failures in
|
|
* the end. Please use this function for short-lived objects.
|
|
*
|
|
* Returns: a pointer to the address that has been mapped, or %NULL on failure
|
|
*/
|
|
void *vm_map_ram(struct page **pages, unsigned int count, int node)
|
|
{
|
|
unsigned long size = (unsigned long)count << PAGE_SHIFT;
|
|
unsigned long addr;
|
|
void *mem;
|
|
|
|
if (likely(count <= VMAP_MAX_ALLOC)) {
|
|
mem = vb_alloc(size, GFP_KERNEL);
|
|
if (IS_ERR(mem))
|
|
return NULL;
|
|
addr = (unsigned long)mem;
|
|
} else {
|
|
struct vmap_area *va;
|
|
va = alloc_vmap_area(size, PAGE_SIZE,
|
|
VMALLOC_START, VMALLOC_END, node, GFP_KERNEL);
|
|
if (IS_ERR(va))
|
|
return NULL;
|
|
|
|
addr = va->va_start;
|
|
mem = (void *)addr;
|
|
}
|
|
|
|
kasan_unpoison_vmalloc(mem, size);
|
|
|
|
if (map_kernel_range(addr, size, PAGE_KERNEL, pages) < 0) {
|
|
vm_unmap_ram(mem, count);
|
|
return NULL;
|
|
}
|
|
return mem;
|
|
}
|
|
EXPORT_SYMBOL(vm_map_ram);
|
|
|
|
static struct vm_struct *vmlist __initdata;
|
|
|
|
/**
|
|
* vm_area_add_early - add vmap area early during boot
|
|
* @vm: vm_struct to add
|
|
*
|
|
* This function is used to add fixed kernel vm area to vmlist before
|
|
* vmalloc_init() is called. @vm->addr, @vm->size, and @vm->flags
|
|
* should contain proper values and the other fields should be zero.
|
|
*
|
|
* DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
|
|
*/
|
|
void __init vm_area_add_early(struct vm_struct *vm)
|
|
{
|
|
struct vm_struct *tmp, **p;
|
|
|
|
BUG_ON(vmap_initialized);
|
|
for (p = &vmlist; (tmp = *p) != NULL; p = &tmp->next) {
|
|
if (tmp->addr >= vm->addr) {
|
|
BUG_ON(tmp->addr < vm->addr + vm->size);
|
|
break;
|
|
} else
|
|
BUG_ON(tmp->addr + tmp->size > vm->addr);
|
|
}
|
|
vm->next = *p;
|
|
*p = vm;
|
|
}
|
|
|
|
/**
|
|
* vm_area_register_early - register vmap area early during boot
|
|
* @vm: vm_struct to register
|
|
* @align: requested alignment
|
|
*
|
|
* This function is used to register kernel vm area before
|
|
* vmalloc_init() is called. @vm->size and @vm->flags should contain
|
|
* proper values on entry and other fields should be zero. On return,
|
|
* vm->addr contains the allocated address.
|
|
*
|
|
* DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
|
|
*/
|
|
void __init vm_area_register_early(struct vm_struct *vm, size_t align)
|
|
{
|
|
static size_t vm_init_off __initdata;
|
|
unsigned long addr;
|
|
|
|
addr = ALIGN(VMALLOC_START + vm_init_off, align);
|
|
vm_init_off = PFN_ALIGN(addr + vm->size) - VMALLOC_START;
|
|
|
|
vm->addr = (void *)addr;
|
|
|
|
vm_area_add_early(vm);
|
|
}
|
|
|
|
static void vmap_init_free_space(void)
|
|
{
|
|
unsigned long vmap_start = 1;
|
|
const unsigned long vmap_end = ULONG_MAX;
|
|
struct vmap_area *busy, *free;
|
|
|
|
/*
|
|
* B F B B B F
|
|
* -|-----|.....|-----|-----|-----|.....|-
|
|
* | The KVA space |
|
|
* |<--------------------------------->|
|
|
*/
|
|
list_for_each_entry(busy, &vmap_area_list, list) {
|
|
if (busy->va_start - vmap_start > 0) {
|
|
free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
|
|
if (!WARN_ON_ONCE(!free)) {
|
|
free->va_start = vmap_start;
|
|
free->va_end = busy->va_start;
|
|
|
|
insert_vmap_area_augment(free, NULL,
|
|
&free_vmap_area_root,
|
|
&free_vmap_area_list);
|
|
}
|
|
}
|
|
|
|
vmap_start = busy->va_end;
|
|
}
|
|
|
|
if (vmap_end - vmap_start > 0) {
|
|
free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
|
|
if (!WARN_ON_ONCE(!free)) {
|
|
free->va_start = vmap_start;
|
|
free->va_end = vmap_end;
|
|
|
|
insert_vmap_area_augment(free, NULL,
|
|
&free_vmap_area_root,
|
|
&free_vmap_area_list);
|
|
}
|
|
}
|
|
}
|
|
|
|
void __init vmalloc_init(void)
|
|
{
|
|
struct vmap_area *va;
|
|
struct vm_struct *tmp;
|
|
int i;
|
|
|
|
/*
|
|
* Create the cache for vmap_area objects.
|
|
*/
|
|
vmap_area_cachep = KMEM_CACHE(vmap_area, SLAB_PANIC);
|
|
|
|
for_each_possible_cpu(i) {
|
|
struct vmap_block_queue *vbq;
|
|
struct vfree_deferred *p;
|
|
|
|
vbq = &per_cpu(vmap_block_queue, i);
|
|
spin_lock_init(&vbq->lock);
|
|
INIT_LIST_HEAD(&vbq->free);
|
|
p = &per_cpu(vfree_deferred, i);
|
|
init_llist_head(&p->list);
|
|
INIT_WORK(&p->wq, free_work);
|
|
}
|
|
|
|
/* Import existing vmlist entries. */
|
|
for (tmp = vmlist; tmp; tmp = tmp->next) {
|
|
va = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
|
|
if (WARN_ON_ONCE(!va))
|
|
continue;
|
|
|
|
va->va_start = (unsigned long)tmp->addr;
|
|
va->va_end = va->va_start + tmp->size;
|
|
va->vm = tmp;
|
|
insert_vmap_area(va, &vmap_area_root, &vmap_area_list);
|
|
}
|
|
|
|
/*
|
|
* Now we can initialize a free vmap space.
|
|
*/
|
|
vmap_init_free_space();
|
|
vmap_initialized = true;
|
|
}
|
|
|
|
/**
|
|
* unmap_kernel_range - unmap kernel VM area and flush cache and TLB
|
|
* @addr: start of the VM area to unmap
|
|
* @size: size of the VM area to unmap
|
|
*
|
|
* Similar to unmap_kernel_range_noflush() but flushes vcache before
|
|
* the unmapping and tlb after.
|
|
*/
|
|
void unmap_kernel_range(unsigned long addr, unsigned long size)
|
|
{
|
|
unsigned long end = addr + size;
|
|
|
|
flush_cache_vunmap(addr, end);
|
|
unmap_kernel_range_noflush(addr, size);
|
|
flush_tlb_kernel_range(addr, end);
|
|
}
|
|
|
|
static inline void setup_vmalloc_vm_locked(struct vm_struct *vm,
|
|
struct vmap_area *va, unsigned long flags, const void *caller)
|
|
{
|
|
vm->flags = flags;
|
|
vm->addr = (void *)va->va_start;
|
|
vm->size = va->va_end - va->va_start;
|
|
vm->caller = caller;
|
|
va->vm = vm;
|
|
}
|
|
|
|
static void setup_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va,
|
|
unsigned long flags, const void *caller)
|
|
{
|
|
spin_lock(&vmap_area_lock);
|
|
setup_vmalloc_vm_locked(vm, va, flags, caller);
|
|
spin_unlock(&vmap_area_lock);
|
|
}
|
|
|
|
static void clear_vm_uninitialized_flag(struct vm_struct *vm)
|
|
{
|
|
/*
|
|
* Before removing VM_UNINITIALIZED,
|
|
* we should make sure that vm has proper values.
|
|
* Pair with smp_rmb() in show_numa_info().
|
|
*/
|
|
smp_wmb();
|
|
vm->flags &= ~VM_UNINITIALIZED;
|
|
}
|
|
|
|
static struct vm_struct *__get_vm_area_node(unsigned long size,
|
|
unsigned long align, unsigned long flags, unsigned long start,
|
|
unsigned long end, int node, gfp_t gfp_mask, const void *caller)
|
|
{
|
|
struct vmap_area *va;
|
|
struct vm_struct *area;
|
|
unsigned long requested_size = size;
|
|
|
|
BUG_ON(in_interrupt());
|
|
size = PAGE_ALIGN(size);
|
|
if (unlikely(!size))
|
|
return NULL;
|
|
|
|
if (flags & VM_IOREMAP)
|
|
align = 1ul << clamp_t(int, get_count_order_long(size),
|
|
PAGE_SHIFT, IOREMAP_MAX_ORDER);
|
|
|
|
area = kzalloc_node(sizeof(*area), gfp_mask & GFP_RECLAIM_MASK, node);
|
|
if (unlikely(!area))
|
|
return NULL;
|
|
|
|
if (!(flags & VM_NO_GUARD))
|
|
size += PAGE_SIZE;
|
|
|
|
va = alloc_vmap_area(size, align, start, end, node, gfp_mask);
|
|
if (IS_ERR(va)) {
|
|
kfree(area);
|
|
return NULL;
|
|
}
|
|
|
|
kasan_unpoison_vmalloc((void *)va->va_start, requested_size);
|
|
|
|
setup_vmalloc_vm(area, va, flags, caller);
|
|
|
|
return area;
|
|
}
|
|
|
|
struct vm_struct *__get_vm_area_caller(unsigned long size, unsigned long flags,
|
|
unsigned long start, unsigned long end,
|
|
const void *caller)
|
|
{
|
|
return __get_vm_area_node(size, 1, flags, start, end, NUMA_NO_NODE,
|
|
GFP_KERNEL, caller);
|
|
}
|
|
|
|
/**
|
|
* get_vm_area - reserve a contiguous kernel virtual area
|
|
* @size: size of the area
|
|
* @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC
|
|
*
|
|
* Search an area of @size in the kernel virtual mapping area,
|
|
* and reserved it for out purposes. Returns the area descriptor
|
|
* on success or %NULL on failure.
|
|
*
|
|
* Return: the area descriptor on success or %NULL on failure.
|
|
*/
|
|
struct vm_struct *get_vm_area(unsigned long size, unsigned long flags)
|
|
{
|
|
return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END,
|
|
NUMA_NO_NODE, GFP_KERNEL,
|
|
__builtin_return_address(0));
|
|
}
|
|
|
|
struct vm_struct *get_vm_area_caller(unsigned long size, unsigned long flags,
|
|
const void *caller)
|
|
{
|
|
return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END,
|
|
NUMA_NO_NODE, GFP_KERNEL, caller);
|
|
}
|
|
|
|
/**
|
|
* find_vm_area - find a continuous kernel virtual area
|
|
* @addr: base address
|
|
*
|
|
* Search for the kernel VM area starting at @addr, and return it.
|
|
* It is up to the caller to do all required locking to keep the returned
|
|
* pointer valid.
|
|
*
|
|
* Return: the area descriptor on success or %NULL on failure.
|
|
*/
|
|
struct vm_struct *find_vm_area(const void *addr)
|
|
{
|
|
struct vmap_area *va;
|
|
|
|
va = find_vmap_area((unsigned long)addr);
|
|
if (!va)
|
|
return NULL;
|
|
|
|
return va->vm;
|
|
}
|
|
|
|
/**
|
|
* remove_vm_area - find and remove a continuous kernel virtual area
|
|
* @addr: base address
|
|
*
|
|
* Search for the kernel VM area starting at @addr, and remove it.
|
|
* This function returns the found VM area, but using it is NOT safe
|
|
* on SMP machines, except for its size or flags.
|
|
*
|
|
* Return: the area descriptor on success or %NULL on failure.
|
|
*/
|
|
struct vm_struct *remove_vm_area(const void *addr)
|
|
{
|
|
struct vmap_area *va;
|
|
|
|
might_sleep();
|
|
|
|
spin_lock(&vmap_area_lock);
|
|
va = __find_vmap_area((unsigned long)addr);
|
|
if (va && va->vm) {
|
|
struct vm_struct *vm = va->vm;
|
|
|
|
va->vm = NULL;
|
|
spin_unlock(&vmap_area_lock);
|
|
|
|
kasan_free_shadow(vm);
|
|
free_unmap_vmap_area(va);
|
|
|
|
return vm;
|
|
}
|
|
|
|
spin_unlock(&vmap_area_lock);
|
|
return NULL;
|
|
}
|
|
|
|
static inline void set_area_direct_map(const struct vm_struct *area,
|
|
int (*set_direct_map)(struct page *page))
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < area->nr_pages; i++)
|
|
if (page_address(area->pages[i]))
|
|
set_direct_map(area->pages[i]);
|
|
}
|
|
|
|
/* Handle removing and resetting vm mappings related to the vm_struct. */
|
|
static void vm_remove_mappings(struct vm_struct *area, int deallocate_pages)
|
|
{
|
|
unsigned long start = ULONG_MAX, end = 0;
|
|
int flush_reset = area->flags & VM_FLUSH_RESET_PERMS;
|
|
int flush_dmap = 0;
|
|
int i;
|
|
|
|
remove_vm_area(area->addr);
|
|
|
|
/* If this is not VM_FLUSH_RESET_PERMS memory, no need for the below. */
|
|
if (!flush_reset)
|
|
return;
|
|
|
|
/*
|
|
* If not deallocating pages, just do the flush of the VM area and
|
|
* return.
|
|
*/
|
|
if (!deallocate_pages) {
|
|
vm_unmap_aliases();
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If execution gets here, flush the vm mapping and reset the direct
|
|
* map. Find the start and end range of the direct mappings to make sure
|
|
* the vm_unmap_aliases() flush includes the direct map.
|
|
*/
|
|
for (i = 0; i < area->nr_pages; i++) {
|
|
unsigned long addr = (unsigned long)page_address(area->pages[i]);
|
|
if (addr) {
|
|
start = min(addr, start);
|
|
end = max(addr + PAGE_SIZE, end);
|
|
flush_dmap = 1;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Set direct map to something invalid so that it won't be cached if
|
|
* there are any accesses after the TLB flush, then flush the TLB and
|
|
* reset the direct map permissions to the default.
|
|
*/
|
|
set_area_direct_map(area, set_direct_map_invalid_noflush);
|
|
_vm_unmap_aliases(start, end, flush_dmap);
|
|
set_area_direct_map(area, set_direct_map_default_noflush);
|
|
}
|
|
|
|
static void __vunmap(const void *addr, int deallocate_pages)
|
|
{
|
|
struct vm_struct *area;
|
|
|
|
if (!addr)
|
|
return;
|
|
|
|
if (WARN(!PAGE_ALIGNED(addr), "Trying to vfree() bad address (%p)\n",
|
|
addr))
|
|
return;
|
|
|
|
area = find_vm_area(addr);
|
|
if (unlikely(!area)) {
|
|
WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n",
|
|
addr);
|
|
return;
|
|
}
|
|
|
|
debug_check_no_locks_freed(area->addr, get_vm_area_size(area));
|
|
debug_check_no_obj_freed(area->addr, get_vm_area_size(area));
|
|
|
|
kasan_poison_vmalloc(area->addr, get_vm_area_size(area));
|
|
|
|
vm_remove_mappings(area, deallocate_pages);
|
|
|
|
if (deallocate_pages) {
|
|
int i;
|
|
|
|
for (i = 0; i < area->nr_pages; i++) {
|
|
struct page *page = area->pages[i];
|
|
|
|
BUG_ON(!page);
|
|
__free_pages(page, 0);
|
|
}
|
|
atomic_long_sub(area->nr_pages, &nr_vmalloc_pages);
|
|
|
|
kvfree(area->pages);
|
|
}
|
|
|
|
kfree(area);
|
|
}
|
|
|
|
static inline void __vfree_deferred(const void *addr)
|
|
{
|
|
/*
|
|
* Use raw_cpu_ptr() because this can be called from preemptible
|
|
* context. Preemption is absolutely fine here, because the llist_add()
|
|
* implementation is lockless, so it works even if we are adding to
|
|
* another cpu's list. schedule_work() should be fine with this too.
|
|
*/
|
|
struct vfree_deferred *p = raw_cpu_ptr(&vfree_deferred);
|
|
|
|
if (llist_add((struct llist_node *)addr, &p->list))
|
|
schedule_work(&p->wq);
|
|
}
|
|
|
|
/**
|
|
* vfree_atomic - release memory allocated by vmalloc()
|
|
* @addr: memory base address
|
|
*
|
|
* This one is just like vfree() but can be called in any atomic context
|
|
* except NMIs.
|
|
*/
|
|
void vfree_atomic(const void *addr)
|
|
{
|
|
BUG_ON(in_nmi());
|
|
|
|
kmemleak_free(addr);
|
|
|
|
if (!addr)
|
|
return;
|
|
__vfree_deferred(addr);
|
|
}
|
|
|
|
static void __vfree(const void *addr)
|
|
{
|
|
if (unlikely(in_interrupt()))
|
|
__vfree_deferred(addr);
|
|
else
|
|
__vunmap(addr, 1);
|
|
}
|
|
|
|
/**
|
|
* vfree - Release memory allocated by vmalloc()
|
|
* @addr: Memory base address
|
|
*
|
|
* Free the virtually continuous memory area starting at @addr, as obtained
|
|
* from one of the vmalloc() family of APIs. This will usually also free the
|
|
* physical memory underlying the virtual allocation, but that memory is
|
|
* reference counted, so it will not be freed until the last user goes away.
|
|
*
|
|
* If @addr is NULL, no operation is performed.
|
|
*
|
|
* Context:
|
|
* May sleep if called *not* from interrupt context.
|
|
* Must not be called in NMI context (strictly speaking, it could be
|
|
* if we have CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG, but making the calling
|
|
* conventions for vfree() arch-depenedent would be a really bad idea).
|
|
*/
|
|
void vfree(const void *addr)
|
|
{
|
|
BUG_ON(in_nmi());
|
|
|
|
kmemleak_free(addr);
|
|
|
|
might_sleep_if(!in_interrupt());
|
|
|
|
if (!addr)
|
|
return;
|
|
|
|
__vfree(addr);
|
|
}
|
|
EXPORT_SYMBOL(vfree);
|
|
|
|
/**
|
|
* vunmap - release virtual mapping obtained by vmap()
|
|
* @addr: memory base address
|
|
*
|
|
* Free the virtually contiguous memory area starting at @addr,
|
|
* which was created from the page array passed to vmap().
|
|
*
|
|
* Must not be called in interrupt context.
|
|
*/
|
|
void vunmap(const void *addr)
|
|
{
|
|
BUG_ON(in_interrupt());
|
|
might_sleep();
|
|
if (addr)
|
|
__vunmap(addr, 0);
|
|
}
|
|
EXPORT_SYMBOL(vunmap);
|
|
|
|
/**
|
|
* vmap - map an array of pages into virtually contiguous space
|
|
* @pages: array of page pointers
|
|
* @count: number of pages to map
|
|
* @flags: vm_area->flags
|
|
* @prot: page protection for the mapping
|
|
*
|
|
* Maps @count pages from @pages into contiguous kernel virtual space.
|
|
* If @flags contains %VM_MAP_PUT_PAGES the ownership of the pages array itself
|
|
* (which must be kmalloc or vmalloc memory) and one reference per pages in it
|
|
* are transferred from the caller to vmap(), and will be freed / dropped when
|
|
* vfree() is called on the return value.
|
|
*
|
|
* Return: the address of the area or %NULL on failure
|
|
*/
|
|
void *vmap(struct page **pages, unsigned int count,
|
|
unsigned long flags, pgprot_t prot)
|
|
{
|
|
struct vm_struct *area;
|
|
unsigned long size; /* In bytes */
|
|
|
|
might_sleep();
|
|
|
|
if (count > totalram_pages())
|
|
return NULL;
|
|
|
|
size = (unsigned long)count << PAGE_SHIFT;
|
|
area = get_vm_area_caller(size, flags, __builtin_return_address(0));
|
|
if (!area)
|
|
return NULL;
|
|
|
|
if (map_kernel_range((unsigned long)area->addr, size, pgprot_nx(prot),
|
|
pages) < 0) {
|
|
vunmap(area->addr);
|
|
return NULL;
|
|
}
|
|
|
|
if (flags & VM_MAP_PUT_PAGES) {
|
|
area->pages = pages;
|
|
area->nr_pages = count;
|
|
}
|
|
return area->addr;
|
|
}
|
|
EXPORT_SYMBOL(vmap);
|
|
|
|
#ifdef CONFIG_VMAP_PFN
|
|
struct vmap_pfn_data {
|
|
unsigned long *pfns;
|
|
pgprot_t prot;
|
|
unsigned int idx;
|
|
};
|
|
|
|
static int vmap_pfn_apply(pte_t *pte, unsigned long addr, void *private)
|
|
{
|
|
struct vmap_pfn_data *data = private;
|
|
|
|
if (WARN_ON_ONCE(pfn_valid(data->pfns[data->idx])))
|
|
return -EINVAL;
|
|
*pte = pte_mkspecial(pfn_pte(data->pfns[data->idx++], data->prot));
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* vmap_pfn - map an array of PFNs into virtually contiguous space
|
|
* @pfns: array of PFNs
|
|
* @count: number of pages to map
|
|
* @prot: page protection for the mapping
|
|
*
|
|
* Maps @count PFNs from @pfns into contiguous kernel virtual space and returns
|
|
* the start address of the mapping.
|
|
*/
|
|
void *vmap_pfn(unsigned long *pfns, unsigned int count, pgprot_t prot)
|
|
{
|
|
struct vmap_pfn_data data = { .pfns = pfns, .prot = pgprot_nx(prot) };
|
|
struct vm_struct *area;
|
|
|
|
area = get_vm_area_caller(count * PAGE_SIZE, VM_IOREMAP,
|
|
__builtin_return_address(0));
|
|
if (!area)
|
|
return NULL;
|
|
if (apply_to_page_range(&init_mm, (unsigned long)area->addr,
|
|
count * PAGE_SIZE, vmap_pfn_apply, &data)) {
|
|
free_vm_area(area);
|
|
return NULL;
|
|
}
|
|
return area->addr;
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmap_pfn);
|
|
#endif /* CONFIG_VMAP_PFN */
|
|
|
|
static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
|
|
pgprot_t prot, int node)
|
|
{
|
|
const gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO;
|
|
unsigned int nr_pages = get_vm_area_size(area) >> PAGE_SHIFT;
|
|
unsigned long array_size;
|
|
unsigned int i;
|
|
struct page **pages;
|
|
|
|
array_size = (unsigned long)nr_pages * sizeof(struct page *);
|
|
gfp_mask |= __GFP_NOWARN;
|
|
if (!(gfp_mask & (GFP_DMA | GFP_DMA32)))
|
|
gfp_mask |= __GFP_HIGHMEM;
|
|
|
|
/* Please note that the recursion is strictly bounded. */
|
|
if (array_size > PAGE_SIZE) {
|
|
pages = __vmalloc_node(array_size, 1, nested_gfp, node,
|
|
area->caller);
|
|
} else {
|
|
pages = kmalloc_node(array_size, nested_gfp, node);
|
|
}
|
|
|
|
if (!pages) {
|
|
free_vm_area(area);
|
|
return NULL;
|
|
}
|
|
|
|
area->pages = pages;
|
|
area->nr_pages = nr_pages;
|
|
|
|
for (i = 0; i < area->nr_pages; i++) {
|
|
struct page *page;
|
|
|
|
if (node == NUMA_NO_NODE)
|
|
page = alloc_page(gfp_mask);
|
|
else
|
|
page = alloc_pages_node(node, gfp_mask, 0);
|
|
|
|
if (unlikely(!page)) {
|
|
/* Successfully allocated i pages, free them in __vfree() */
|
|
area->nr_pages = i;
|
|
atomic_long_add(area->nr_pages, &nr_vmalloc_pages);
|
|
goto fail;
|
|
}
|
|
area->pages[i] = page;
|
|
if (gfpflags_allow_blocking(gfp_mask))
|
|
cond_resched();
|
|
}
|
|
atomic_long_add(area->nr_pages, &nr_vmalloc_pages);
|
|
|
|
if (map_kernel_range((unsigned long)area->addr, get_vm_area_size(area),
|
|
prot, pages) < 0)
|
|
goto fail;
|
|
|
|
return area->addr;
|
|
|
|
fail:
|
|
warn_alloc(gfp_mask, NULL,
|
|
"vmalloc: allocation failure, allocated %ld of %ld bytes",
|
|
(area->nr_pages*PAGE_SIZE), area->size);
|
|
__vfree(area->addr);
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* __vmalloc_node_range - allocate virtually contiguous memory
|
|
* @size: allocation size
|
|
* @align: desired alignment
|
|
* @start: vm area range start
|
|
* @end: vm area range end
|
|
* @gfp_mask: flags for the page level allocator
|
|
* @prot: protection mask for the allocated pages
|
|
* @vm_flags: additional vm area flags (e.g. %VM_NO_GUARD)
|
|
* @node: node to use for allocation or NUMA_NO_NODE
|
|
* @caller: caller's return address
|
|
*
|
|
* Allocate enough pages to cover @size from the page level
|
|
* allocator with @gfp_mask flags. Map them into contiguous
|
|
* kernel virtual space, using a pagetable protection of @prot.
|
|
*
|
|
* Return: the address of the area or %NULL on failure
|
|
*/
|
|
void *__vmalloc_node_range(unsigned long size, unsigned long align,
|
|
unsigned long start, unsigned long end, gfp_t gfp_mask,
|
|
pgprot_t prot, unsigned long vm_flags, int node,
|
|
const void *caller)
|
|
{
|
|
struct vm_struct *area;
|
|
void *addr;
|
|
unsigned long real_size = size;
|
|
|
|
size = PAGE_ALIGN(size);
|
|
if (!size || (size >> PAGE_SHIFT) > totalram_pages())
|
|
goto fail;
|
|
|
|
area = __get_vm_area_node(real_size, align, VM_ALLOC | VM_UNINITIALIZED |
|
|
vm_flags, start, end, node, gfp_mask, caller);
|
|
if (!area)
|
|
goto fail;
|
|
|
|
addr = __vmalloc_area_node(area, gfp_mask, prot, node);
|
|
if (!addr)
|
|
return NULL;
|
|
|
|
/*
|
|
* In this function, newly allocated vm_struct has VM_UNINITIALIZED
|
|
* flag. It means that vm_struct is not fully initialized.
|
|
* Now, it is fully initialized, so remove this flag here.
|
|
*/
|
|
clear_vm_uninitialized_flag(area);
|
|
|
|
kmemleak_vmalloc(area, size, gfp_mask);
|
|
|
|
return addr;
|
|
|
|
fail:
|
|
warn_alloc(gfp_mask, NULL,
|
|
"vmalloc: allocation failure: %lu bytes", real_size);
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* __vmalloc_node - allocate virtually contiguous memory
|
|
* @size: allocation size
|
|
* @align: desired alignment
|
|
* @gfp_mask: flags for the page level allocator
|
|
* @node: node to use for allocation or NUMA_NO_NODE
|
|
* @caller: caller's return address
|
|
*
|
|
* Allocate enough pages to cover @size from the page level allocator with
|
|
* @gfp_mask flags. Map them into contiguous kernel virtual space.
|
|
*
|
|
* Reclaim modifiers in @gfp_mask - __GFP_NORETRY, __GFP_RETRY_MAYFAIL
|
|
* and __GFP_NOFAIL are not supported
|
|
*
|
|
* Any use of gfp flags outside of GFP_KERNEL should be consulted
|
|
* with mm people.
|
|
*
|
|
* Return: pointer to the allocated memory or %NULL on error
|
|
*/
|
|
void *__vmalloc_node(unsigned long size, unsigned long align,
|
|
gfp_t gfp_mask, int node, const void *caller)
|
|
{
|
|
return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
|
|
gfp_mask, PAGE_KERNEL, 0, node, caller);
|
|
}
|
|
/*
|
|
* This is only for performance analysis of vmalloc and stress purpose.
|
|
* It is required by vmalloc test module, therefore do not use it other
|
|
* than that.
|
|
*/
|
|
#ifdef CONFIG_TEST_VMALLOC_MODULE
|
|
EXPORT_SYMBOL_GPL(__vmalloc_node);
|
|
#endif
|
|
|
|
void *__vmalloc(unsigned long size, gfp_t gfp_mask)
|
|
{
|
|
return __vmalloc_node(size, 1, gfp_mask, NUMA_NO_NODE,
|
|
__builtin_return_address(0));
|
|
}
|
|
EXPORT_SYMBOL(__vmalloc);
|
|
|
|
/**
|
|
* vmalloc - allocate virtually contiguous memory
|
|
* @size: allocation size
|
|
*
|
|
* Allocate enough pages to cover @size from the page level
|
|
* allocator and map them into contiguous kernel virtual space.
|
|
*
|
|
* For tight control over page level allocator and protection flags
|
|
* use __vmalloc() instead.
|
|
*
|
|
* Return: pointer to the allocated memory or %NULL on error
|
|
*/
|
|
void *vmalloc(unsigned long size)
|
|
{
|
|
return __vmalloc_node(size, 1, GFP_KERNEL, NUMA_NO_NODE,
|
|
__builtin_return_address(0));
|
|
}
|
|
EXPORT_SYMBOL(vmalloc);
|
|
|
|
/**
|
|
* vzalloc - allocate virtually contiguous memory with zero fill
|
|
* @size: allocation size
|
|
*
|
|
* Allocate enough pages to cover @size from the page level
|
|
* allocator and map them into contiguous kernel virtual space.
|
|
* The memory allocated is set to zero.
|
|
*
|
|
* For tight control over page level allocator and protection flags
|
|
* use __vmalloc() instead.
|
|
*
|
|
* Return: pointer to the allocated memory or %NULL on error
|
|
*/
|
|
void *vzalloc(unsigned long size)
|
|
{
|
|
return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_ZERO, NUMA_NO_NODE,
|
|
__builtin_return_address(0));
|
|
}
|
|
EXPORT_SYMBOL(vzalloc);
|
|
|
|
/**
|
|
* vmalloc_user - allocate zeroed virtually contiguous memory for userspace
|
|
* @size: allocation size
|
|
*
|
|
* The resulting memory area is zeroed so it can be mapped to userspace
|
|
* without leaking data.
|
|
*
|
|
* Return: pointer to the allocated memory or %NULL on error
|
|
*/
|
|
void *vmalloc_user(unsigned long size)
|
|
{
|
|
return __vmalloc_node_range(size, SHMLBA, VMALLOC_START, VMALLOC_END,
|
|
GFP_KERNEL | __GFP_ZERO, PAGE_KERNEL,
|
|
VM_USERMAP, NUMA_NO_NODE,
|
|
__builtin_return_address(0));
|
|
}
|
|
EXPORT_SYMBOL(vmalloc_user);
|
|
|
|
/**
|
|
* vmalloc_node - allocate memory on a specific node
|
|
* @size: allocation size
|
|
* @node: numa node
|
|
*
|
|
* Allocate enough pages to cover @size from the page level
|
|
* allocator and map them into contiguous kernel virtual space.
|
|
*
|
|
* For tight control over page level allocator and protection flags
|
|
* use __vmalloc() instead.
|
|
*
|
|
* Return: pointer to the allocated memory or %NULL on error
|
|
*/
|
|
void *vmalloc_node(unsigned long size, int node)
|
|
{
|
|
return __vmalloc_node(size, 1, GFP_KERNEL, node,
|
|
__builtin_return_address(0));
|
|
}
|
|
EXPORT_SYMBOL(vmalloc_node);
|
|
|
|
/**
|
|
* vzalloc_node - allocate memory on a specific node with zero fill
|
|
* @size: allocation size
|
|
* @node: numa node
|
|
*
|
|
* Allocate enough pages to cover @size from the page level
|
|
* allocator and map them into contiguous kernel virtual space.
|
|
* The memory allocated is set to zero.
|
|
*
|
|
* Return: pointer to the allocated memory or %NULL on error
|
|
*/
|
|
void *vzalloc_node(unsigned long size, int node)
|
|
{
|
|
return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_ZERO, node,
|
|
__builtin_return_address(0));
|
|
}
|
|
EXPORT_SYMBOL(vzalloc_node);
|
|
|
|
#if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32)
|
|
#define GFP_VMALLOC32 (GFP_DMA32 | GFP_KERNEL)
|
|
#elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA)
|
|
#define GFP_VMALLOC32 (GFP_DMA | GFP_KERNEL)
|
|
#else
|
|
/*
|
|
* 64b systems should always have either DMA or DMA32 zones. For others
|
|
* GFP_DMA32 should do the right thing and use the normal zone.
|
|
*/
|
|
#define GFP_VMALLOC32 GFP_DMA32 | GFP_KERNEL
|
|
#endif
|
|
|
|
/**
|
|
* vmalloc_32 - allocate virtually contiguous memory (32bit addressable)
|
|
* @size: allocation size
|
|
*
|
|
* Allocate enough 32bit PA addressable pages to cover @size from the
|
|
* page level allocator and map them into contiguous kernel virtual space.
|
|
*
|
|
* Return: pointer to the allocated memory or %NULL on error
|
|
*/
|
|
void *vmalloc_32(unsigned long size)
|
|
{
|
|
return __vmalloc_node(size, 1, GFP_VMALLOC32, NUMA_NO_NODE,
|
|
__builtin_return_address(0));
|
|
}
|
|
EXPORT_SYMBOL(vmalloc_32);
|
|
|
|
/**
|
|
* vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory
|
|
* @size: allocation size
|
|
*
|
|
* The resulting memory area is 32bit addressable and zeroed so it can be
|
|
* mapped to userspace without leaking data.
|
|
*
|
|
* Return: pointer to the allocated memory or %NULL on error
|
|
*/
|
|
void *vmalloc_32_user(unsigned long size)
|
|
{
|
|
return __vmalloc_node_range(size, SHMLBA, VMALLOC_START, VMALLOC_END,
|
|
GFP_VMALLOC32 | __GFP_ZERO, PAGE_KERNEL,
|
|
VM_USERMAP, NUMA_NO_NODE,
|
|
__builtin_return_address(0));
|
|
}
|
|
EXPORT_SYMBOL(vmalloc_32_user);
|
|
|
|
/*
|
|
* small helper routine , copy contents to buf from addr.
|
|
* If the page is not present, fill zero.
|
|
*/
|
|
|
|
static int aligned_vread(char *buf, char *addr, unsigned long count)
|
|
{
|
|
struct page *p;
|
|
int copied = 0;
|
|
|
|
while (count) {
|
|
unsigned long offset, length;
|
|
|
|
offset = offset_in_page(addr);
|
|
length = PAGE_SIZE - offset;
|
|
if (length > count)
|
|
length = count;
|
|
p = vmalloc_to_page(addr);
|
|
/*
|
|
* To do safe access to this _mapped_ area, we need
|
|
* lock. But adding lock here means that we need to add
|
|
* overhead of vmalloc()/vfree() calles for this _debug_
|
|
* interface, rarely used. Instead of that, we'll use
|
|
* kmap() and get small overhead in this access function.
|
|
*/
|
|
if (p) {
|
|
/*
|
|
* we can expect USER0 is not used (see vread/vwrite's
|
|
* function description)
|
|
*/
|
|
void *map = kmap_atomic(p);
|
|
memcpy(buf, map + offset, length);
|
|
kunmap_atomic(map);
|
|
} else
|
|
memset(buf, 0, length);
|
|
|
|
addr += length;
|
|
buf += length;
|
|
copied += length;
|
|
count -= length;
|
|
}
|
|
return copied;
|
|
}
|
|
|
|
static int aligned_vwrite(char *buf, char *addr, unsigned long count)
|
|
{
|
|
struct page *p;
|
|
int copied = 0;
|
|
|
|
while (count) {
|
|
unsigned long offset, length;
|
|
|
|
offset = offset_in_page(addr);
|
|
length = PAGE_SIZE - offset;
|
|
if (length > count)
|
|
length = count;
|
|
p = vmalloc_to_page(addr);
|
|
/*
|
|
* To do safe access to this _mapped_ area, we need
|
|
* lock. But adding lock here means that we need to add
|
|
* overhead of vmalloc()/vfree() calles for this _debug_
|
|
* interface, rarely used. Instead of that, we'll use
|
|
* kmap() and get small overhead in this access function.
|
|
*/
|
|
if (p) {
|
|
/*
|
|
* we can expect USER0 is not used (see vread/vwrite's
|
|
* function description)
|
|
*/
|
|
void *map = kmap_atomic(p);
|
|
memcpy(map + offset, buf, length);
|
|
kunmap_atomic(map);
|
|
}
|
|
addr += length;
|
|
buf += length;
|
|
copied += length;
|
|
count -= length;
|
|
}
|
|
return copied;
|
|
}
|
|
|
|
/**
|
|
* vread() - read vmalloc area in a safe way.
|
|
* @buf: buffer for reading data
|
|
* @addr: vm address.
|
|
* @count: number of bytes to be read.
|
|
*
|
|
* This function checks that addr is a valid vmalloc'ed area, and
|
|
* copy data from that area to a given buffer. If the given memory range
|
|
* of [addr...addr+count) includes some valid address, data is copied to
|
|
* proper area of @buf. If there are memory holes, they'll be zero-filled.
|
|
* IOREMAP area is treated as memory hole and no copy is done.
|
|
*
|
|
* If [addr...addr+count) doesn't includes any intersects with alive
|
|
* vm_struct area, returns 0. @buf should be kernel's buffer.
|
|
*
|
|
* Note: In usual ops, vread() is never necessary because the caller
|
|
* should know vmalloc() area is valid and can use memcpy().
|
|
* This is for routines which have to access vmalloc area without
|
|
* any information, as /dev/kmem.
|
|
*
|
|
* Return: number of bytes for which addr and buf should be increased
|
|
* (same number as @count) or %0 if [addr...addr+count) doesn't
|
|
* include any intersection with valid vmalloc area
|
|
*/
|
|
long vread(char *buf, char *addr, unsigned long count)
|
|
{
|
|
struct vmap_area *va;
|
|
struct vm_struct *vm;
|
|
char *vaddr, *buf_start = buf;
|
|
unsigned long buflen = count;
|
|
unsigned long n;
|
|
|
|
/* Don't allow overflow */
|
|
if ((unsigned long) addr + count < count)
|
|
count = -(unsigned long) addr;
|
|
|
|
spin_lock(&vmap_area_lock);
|
|
list_for_each_entry(va, &vmap_area_list, list) {
|
|
if (!count)
|
|
break;
|
|
|
|
if (!va->vm)
|
|
continue;
|
|
|
|
vm = va->vm;
|
|
vaddr = (char *) vm->addr;
|
|
if (addr >= vaddr + get_vm_area_size(vm))
|
|
continue;
|
|
while (addr < vaddr) {
|
|
if (count == 0)
|
|
goto finished;
|
|
*buf = '\0';
|
|
buf++;
|
|
addr++;
|
|
count--;
|
|
}
|
|
n = vaddr + get_vm_area_size(vm) - addr;
|
|
if (n > count)
|
|
n = count;
|
|
if (!(vm->flags & VM_IOREMAP))
|
|
aligned_vread(buf, addr, n);
|
|
else /* IOREMAP area is treated as memory hole */
|
|
memset(buf, 0, n);
|
|
buf += n;
|
|
addr += n;
|
|
count -= n;
|
|
}
|
|
finished:
|
|
spin_unlock(&vmap_area_lock);
|
|
|
|
if (buf == buf_start)
|
|
return 0;
|
|
/* zero-fill memory holes */
|
|
if (buf != buf_start + buflen)
|
|
memset(buf, 0, buflen - (buf - buf_start));
|
|
|
|
return buflen;
|
|
}
|
|
|
|
/**
|
|
* vwrite() - write vmalloc area in a safe way.
|
|
* @buf: buffer for source data
|
|
* @addr: vm address.
|
|
* @count: number of bytes to be read.
|
|
*
|
|
* This function checks that addr is a valid vmalloc'ed area, and
|
|
* copy data from a buffer to the given addr. If specified range of
|
|
* [addr...addr+count) includes some valid address, data is copied from
|
|
* proper area of @buf. If there are memory holes, no copy to hole.
|
|
* IOREMAP area is treated as memory hole and no copy is done.
|
|
*
|
|
* If [addr...addr+count) doesn't includes any intersects with alive
|
|
* vm_struct area, returns 0. @buf should be kernel's buffer.
|
|
*
|
|
* Note: In usual ops, vwrite() is never necessary because the caller
|
|
* should know vmalloc() area is valid and can use memcpy().
|
|
* This is for routines which have to access vmalloc area without
|
|
* any information, as /dev/kmem.
|
|
*
|
|
* Return: number of bytes for which addr and buf should be
|
|
* increased (same number as @count) or %0 if [addr...addr+count)
|
|
* doesn't include any intersection with valid vmalloc area
|
|
*/
|
|
long vwrite(char *buf, char *addr, unsigned long count)
|
|
{
|
|
struct vmap_area *va;
|
|
struct vm_struct *vm;
|
|
char *vaddr;
|
|
unsigned long n, buflen;
|
|
int copied = 0;
|
|
|
|
/* Don't allow overflow */
|
|
if ((unsigned long) addr + count < count)
|
|
count = -(unsigned long) addr;
|
|
buflen = count;
|
|
|
|
spin_lock(&vmap_area_lock);
|
|
list_for_each_entry(va, &vmap_area_list, list) {
|
|
if (!count)
|
|
break;
|
|
|
|
if (!va->vm)
|
|
continue;
|
|
|
|
vm = va->vm;
|
|
vaddr = (char *) vm->addr;
|
|
if (addr >= vaddr + get_vm_area_size(vm))
|
|
continue;
|
|
while (addr < vaddr) {
|
|
if (count == 0)
|
|
goto finished;
|
|
buf++;
|
|
addr++;
|
|
count--;
|
|
}
|
|
n = vaddr + get_vm_area_size(vm) - addr;
|
|
if (n > count)
|
|
n = count;
|
|
if (!(vm->flags & VM_IOREMAP)) {
|
|
aligned_vwrite(buf, addr, n);
|
|
copied++;
|
|
}
|
|
buf += n;
|
|
addr += n;
|
|
count -= n;
|
|
}
|
|
finished:
|
|
spin_unlock(&vmap_area_lock);
|
|
if (!copied)
|
|
return 0;
|
|
return buflen;
|
|
}
|
|
|
|
/**
|
|
* remap_vmalloc_range_partial - map vmalloc pages to userspace
|
|
* @vma: vma to cover
|
|
* @uaddr: target user address to start at
|
|
* @kaddr: virtual address of vmalloc kernel memory
|
|
* @pgoff: offset from @kaddr to start at
|
|
* @size: size of map area
|
|
*
|
|
* Returns: 0 for success, -Exxx on failure
|
|
*
|
|
* This function checks that @kaddr is a valid vmalloc'ed area,
|
|
* and that it is big enough to cover the range starting at
|
|
* @uaddr in @vma. Will return failure if that criteria isn't
|
|
* met.
|
|
*
|
|
* Similar to remap_pfn_range() (see mm/memory.c)
|
|
*/
|
|
int remap_vmalloc_range_partial(struct vm_area_struct *vma, unsigned long uaddr,
|
|
void *kaddr, unsigned long pgoff,
|
|
unsigned long size)
|
|
{
|
|
struct vm_struct *area;
|
|
unsigned long off;
|
|
unsigned long end_index;
|
|
|
|
if (check_shl_overflow(pgoff, PAGE_SHIFT, &off))
|
|
return -EINVAL;
|
|
|
|
size = PAGE_ALIGN(size);
|
|
|
|
if (!PAGE_ALIGNED(uaddr) || !PAGE_ALIGNED(kaddr))
|
|
return -EINVAL;
|
|
|
|
area = find_vm_area(kaddr);
|
|
if (!area)
|
|
return -EINVAL;
|
|
|
|
if (!(area->flags & (VM_USERMAP | VM_DMA_COHERENT)))
|
|
return -EINVAL;
|
|
|
|
if (check_add_overflow(size, off, &end_index) ||
|
|
end_index > get_vm_area_size(area))
|
|
return -EINVAL;
|
|
kaddr += off;
|
|
|
|
do {
|
|
struct page *page = vmalloc_to_page(kaddr);
|
|
int ret;
|
|
|
|
ret = vm_insert_page(vma, uaddr, page);
|
|
if (ret)
|
|
return ret;
|
|
|
|
uaddr += PAGE_SIZE;
|
|
kaddr += PAGE_SIZE;
|
|
size -= PAGE_SIZE;
|
|
} while (size > 0);
|
|
|
|
vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(remap_vmalloc_range_partial);
|
|
|
|
/**
|
|
* remap_vmalloc_range - map vmalloc pages to userspace
|
|
* @vma: vma to cover (map full range of vma)
|
|
* @addr: vmalloc memory
|
|
* @pgoff: number of pages into addr before first page to map
|
|
*
|
|
* Returns: 0 for success, -Exxx on failure
|
|
*
|
|
* This function checks that addr is a valid vmalloc'ed area, and
|
|
* that it is big enough to cover the vma. Will return failure if
|
|
* that criteria isn't met.
|
|
*
|
|
* Similar to remap_pfn_range() (see mm/memory.c)
|
|
*/
|
|
int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
|
|
unsigned long pgoff)
|
|
{
|
|
return remap_vmalloc_range_partial(vma, vma->vm_start,
|
|
addr, pgoff,
|
|
vma->vm_end - vma->vm_start);
|
|
}
|
|
EXPORT_SYMBOL(remap_vmalloc_range);
|
|
|
|
void free_vm_area(struct vm_struct *area)
|
|
{
|
|
struct vm_struct *ret;
|
|
ret = remove_vm_area(area->addr);
|
|
BUG_ON(ret != area);
|
|
kfree(area);
|
|
}
|
|
EXPORT_SYMBOL_GPL(free_vm_area);
|
|
|
|
#ifdef CONFIG_SMP
|
|
static struct vmap_area *node_to_va(struct rb_node *n)
|
|
{
|
|
return rb_entry_safe(n, struct vmap_area, rb_node);
|
|
}
|
|
|
|
/**
|
|
* pvm_find_va_enclose_addr - find the vmap_area @addr belongs to
|
|
* @addr: target address
|
|
*
|
|
* Returns: vmap_area if it is found. If there is no such area
|
|
* the first highest(reverse order) vmap_area is returned
|
|
* i.e. va->va_start < addr && va->va_end < addr or NULL
|
|
* if there are no any areas before @addr.
|
|
*/
|
|
static struct vmap_area *
|
|
pvm_find_va_enclose_addr(unsigned long addr)
|
|
{
|
|
struct vmap_area *va, *tmp;
|
|
struct rb_node *n;
|
|
|
|
n = free_vmap_area_root.rb_node;
|
|
va = NULL;
|
|
|
|
while (n) {
|
|
tmp = rb_entry(n, struct vmap_area, rb_node);
|
|
if (tmp->va_start <= addr) {
|
|
va = tmp;
|
|
if (tmp->va_end >= addr)
|
|
break;
|
|
|
|
n = n->rb_right;
|
|
} else {
|
|
n = n->rb_left;
|
|
}
|
|
}
|
|
|
|
return va;
|
|
}
|
|
|
|
/**
|
|
* pvm_determine_end_from_reverse - find the highest aligned address
|
|
* of free block below VMALLOC_END
|
|
* @va:
|
|
* in - the VA we start the search(reverse order);
|
|
* out - the VA with the highest aligned end address.
|
|
* @align: alignment for required highest address
|
|
*
|
|
* Returns: determined end address within vmap_area
|
|
*/
|
|
static unsigned long
|
|
pvm_determine_end_from_reverse(struct vmap_area **va, unsigned long align)
|
|
{
|
|
unsigned long vmalloc_end = VMALLOC_END & ~(align - 1);
|
|
unsigned long addr;
|
|
|
|
if (likely(*va)) {
|
|
list_for_each_entry_from_reverse((*va),
|
|
&free_vmap_area_list, list) {
|
|
addr = min((*va)->va_end & ~(align - 1), vmalloc_end);
|
|
if ((*va)->va_start < addr)
|
|
return addr;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* pcpu_get_vm_areas - allocate vmalloc areas for percpu allocator
|
|
* @offsets: array containing offset of each area
|
|
* @sizes: array containing size of each area
|
|
* @nr_vms: the number of areas to allocate
|
|
* @align: alignment, all entries in @offsets and @sizes must be aligned to this
|
|
*
|
|
* Returns: kmalloc'd vm_struct pointer array pointing to allocated
|
|
* vm_structs on success, %NULL on failure
|
|
*
|
|
* Percpu allocator wants to use congruent vm areas so that it can
|
|
* maintain the offsets among percpu areas. This function allocates
|
|
* congruent vmalloc areas for it with GFP_KERNEL. These areas tend to
|
|
* be scattered pretty far, distance between two areas easily going up
|
|
* to gigabytes. To avoid interacting with regular vmallocs, these
|
|
* areas are allocated from top.
|
|
*
|
|
* Despite its complicated look, this allocator is rather simple. It
|
|
* does everything top-down and scans free blocks from the end looking
|
|
* for matching base. While scanning, if any of the areas do not fit the
|
|
* base address is pulled down to fit the area. Scanning is repeated till
|
|
* all the areas fit and then all necessary data structures are inserted
|
|
* and the result is returned.
|
|
*/
|
|
struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
|
|
const size_t *sizes, int nr_vms,
|
|
size_t align)
|
|
{
|
|
const unsigned long vmalloc_start = ALIGN(VMALLOC_START, align);
|
|
const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1);
|
|
struct vmap_area **vas, *va;
|
|
struct vm_struct **vms;
|
|
int area, area2, last_area, term_area;
|
|
unsigned long base, start, size, end, last_end, orig_start, orig_end;
|
|
bool purged = false;
|
|
enum fit_type type;
|
|
|
|
/* verify parameters and allocate data structures */
|
|
BUG_ON(offset_in_page(align) || !is_power_of_2(align));
|
|
for (last_area = 0, area = 0; area < nr_vms; area++) {
|
|
start = offsets[area];
|
|
end = start + sizes[area];
|
|
|
|
/* is everything aligned properly? */
|
|
BUG_ON(!IS_ALIGNED(offsets[area], align));
|
|
BUG_ON(!IS_ALIGNED(sizes[area], align));
|
|
|
|
/* detect the area with the highest address */
|
|
if (start > offsets[last_area])
|
|
last_area = area;
|
|
|
|
for (area2 = area + 1; area2 < nr_vms; area2++) {
|
|
unsigned long start2 = offsets[area2];
|
|
unsigned long end2 = start2 + sizes[area2];
|
|
|
|
BUG_ON(start2 < end && start < end2);
|
|
}
|
|
}
|
|
last_end = offsets[last_area] + sizes[last_area];
|
|
|
|
if (vmalloc_end - vmalloc_start < last_end) {
|
|
WARN_ON(true);
|
|
return NULL;
|
|
}
|
|
|
|
vms = kcalloc(nr_vms, sizeof(vms[0]), GFP_KERNEL);
|
|
vas = kcalloc(nr_vms, sizeof(vas[0]), GFP_KERNEL);
|
|
if (!vas || !vms)
|
|
goto err_free2;
|
|
|
|
for (area = 0; area < nr_vms; area++) {
|
|
vas[area] = kmem_cache_zalloc(vmap_area_cachep, GFP_KERNEL);
|
|
vms[area] = kzalloc(sizeof(struct vm_struct), GFP_KERNEL);
|
|
if (!vas[area] || !vms[area])
|
|
goto err_free;
|
|
}
|
|
retry:
|
|
spin_lock(&free_vmap_area_lock);
|
|
|
|
/* start scanning - we scan from the top, begin with the last area */
|
|
area = term_area = last_area;
|
|
start = offsets[area];
|
|
end = start + sizes[area];
|
|
|
|
va = pvm_find_va_enclose_addr(vmalloc_end);
|
|
base = pvm_determine_end_from_reverse(&va, align) - end;
|
|
|
|
while (true) {
|
|
/*
|
|
* base might have underflowed, add last_end before
|
|
* comparing.
|
|
*/
|
|
if (base + last_end < vmalloc_start + last_end)
|
|
goto overflow;
|
|
|
|
/*
|
|
* Fitting base has not been found.
|
|
*/
|
|
if (va == NULL)
|
|
goto overflow;
|
|
|
|
/*
|
|
* If required width exceeds current VA block, move
|
|
* base downwards and then recheck.
|
|
*/
|
|
if (base + end > va->va_end) {
|
|
base = pvm_determine_end_from_reverse(&va, align) - end;
|
|
term_area = area;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* If this VA does not fit, move base downwards and recheck.
|
|
*/
|
|
if (base + start < va->va_start) {
|
|
va = node_to_va(rb_prev(&va->rb_node));
|
|
base = pvm_determine_end_from_reverse(&va, align) - end;
|
|
term_area = area;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* This area fits, move on to the previous one. If
|
|
* the previous one is the terminal one, we're done.
|
|
*/
|
|
area = (area + nr_vms - 1) % nr_vms;
|
|
if (area == term_area)
|
|
break;
|
|
|
|
start = offsets[area];
|
|
end = start + sizes[area];
|
|
va = pvm_find_va_enclose_addr(base + end);
|
|
}
|
|
|
|
/* we've found a fitting base, insert all va's */
|
|
for (area = 0; area < nr_vms; area++) {
|
|
int ret;
|
|
|
|
start = base + offsets[area];
|
|
size = sizes[area];
|
|
|
|
va = pvm_find_va_enclose_addr(start);
|
|
if (WARN_ON_ONCE(va == NULL))
|
|
/* It is a BUG(), but trigger recovery instead. */
|
|
goto recovery;
|
|
|
|
type = classify_va_fit_type(va, start, size);
|
|
if (WARN_ON_ONCE(type == NOTHING_FIT))
|
|
/* It is a BUG(), but trigger recovery instead. */
|
|
goto recovery;
|
|
|
|
ret = adjust_va_to_fit_type(va, start, size, type);
|
|
if (unlikely(ret))
|
|
goto recovery;
|
|
|
|
/* Allocated area. */
|
|
va = vas[area];
|
|
va->va_start = start;
|
|
va->va_end = start + size;
|
|
}
|
|
|
|
spin_unlock(&free_vmap_area_lock);
|
|
|
|
/* populate the kasan shadow space */
|
|
for (area = 0; area < nr_vms; area++) {
|
|
if (kasan_populate_vmalloc(vas[area]->va_start, sizes[area]))
|
|
goto err_free_shadow;
|
|
|
|
kasan_unpoison_vmalloc((void *)vas[area]->va_start,
|
|
sizes[area]);
|
|
}
|
|
|
|
/* insert all vm's */
|
|
spin_lock(&vmap_area_lock);
|
|
for (area = 0; area < nr_vms; area++) {
|
|
insert_vmap_area(vas[area], &vmap_area_root, &vmap_area_list);
|
|
|
|
setup_vmalloc_vm_locked(vms[area], vas[area], VM_ALLOC,
|
|
pcpu_get_vm_areas);
|
|
}
|
|
spin_unlock(&vmap_area_lock);
|
|
|
|
kfree(vas);
|
|
return vms;
|
|
|
|
recovery:
|
|
/*
|
|
* Remove previously allocated areas. There is no
|
|
* need in removing these areas from the busy tree,
|
|
* because they are inserted only on the final step
|
|
* and when pcpu_get_vm_areas() is success.
|
|
*/
|
|
while (area--) {
|
|
orig_start = vas[area]->va_start;
|
|
orig_end = vas[area]->va_end;
|
|
va = merge_or_add_vmap_area_augment(vas[area], &free_vmap_area_root,
|
|
&free_vmap_area_list);
|
|
if (va)
|
|
kasan_release_vmalloc(orig_start, orig_end,
|
|
va->va_start, va->va_end);
|
|
vas[area] = NULL;
|
|
}
|
|
|
|
overflow:
|
|
spin_unlock(&free_vmap_area_lock);
|
|
if (!purged) {
|
|
purge_vmap_area_lazy();
|
|
purged = true;
|
|
|
|
/* Before "retry", check if we recover. */
|
|
for (area = 0; area < nr_vms; area++) {
|
|
if (vas[area])
|
|
continue;
|
|
|
|
vas[area] = kmem_cache_zalloc(
|
|
vmap_area_cachep, GFP_KERNEL);
|
|
if (!vas[area])
|
|
goto err_free;
|
|
}
|
|
|
|
goto retry;
|
|
}
|
|
|
|
err_free:
|
|
for (area = 0; area < nr_vms; area++) {
|
|
if (vas[area])
|
|
kmem_cache_free(vmap_area_cachep, vas[area]);
|
|
|
|
kfree(vms[area]);
|
|
}
|
|
err_free2:
|
|
kfree(vas);
|
|
kfree(vms);
|
|
return NULL;
|
|
|
|
err_free_shadow:
|
|
spin_lock(&free_vmap_area_lock);
|
|
/*
|
|
* We release all the vmalloc shadows, even the ones for regions that
|
|
* hadn't been successfully added. This relies on kasan_release_vmalloc
|
|
* being able to tolerate this case.
|
|
*/
|
|
for (area = 0; area < nr_vms; area++) {
|
|
orig_start = vas[area]->va_start;
|
|
orig_end = vas[area]->va_end;
|
|
va = merge_or_add_vmap_area_augment(vas[area], &free_vmap_area_root,
|
|
&free_vmap_area_list);
|
|
if (va)
|
|
kasan_release_vmalloc(orig_start, orig_end,
|
|
va->va_start, va->va_end);
|
|
vas[area] = NULL;
|
|
kfree(vms[area]);
|
|
}
|
|
spin_unlock(&free_vmap_area_lock);
|
|
kfree(vas);
|
|
kfree(vms);
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* pcpu_free_vm_areas - free vmalloc areas for percpu allocator
|
|
* @vms: vm_struct pointer array returned by pcpu_get_vm_areas()
|
|
* @nr_vms: the number of allocated areas
|
|
*
|
|
* Free vm_structs and the array allocated by pcpu_get_vm_areas().
|
|
*/
|
|
void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < nr_vms; i++)
|
|
free_vm_area(vms[i]);
|
|
kfree(vms);
|
|
}
|
|
#endif /* CONFIG_SMP */
|
|
|
|
bool vmalloc_dump_obj(void *object)
|
|
{
|
|
struct vm_struct *vm;
|
|
void *objp = (void *)PAGE_ALIGN((unsigned long)object);
|
|
|
|
vm = find_vm_area(objp);
|
|
if (!vm)
|
|
return false;
|
|
pr_cont(" %u-page vmalloc region starting at %#lx allocated at %pS\n",
|
|
vm->nr_pages, (unsigned long)vm->addr, vm->caller);
|
|
return true;
|
|
}
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static void *s_start(struct seq_file *m, loff_t *pos)
|
|
__acquires(&vmap_purge_lock)
|
|
__acquires(&vmap_area_lock)
|
|
{
|
|
mutex_lock(&vmap_purge_lock);
|
|
spin_lock(&vmap_area_lock);
|
|
|
|
return seq_list_start(&vmap_area_list, *pos);
|
|
}
|
|
|
|
static void *s_next(struct seq_file *m, void *p, loff_t *pos)
|
|
{
|
|
return seq_list_next(p, &vmap_area_list, pos);
|
|
}
|
|
|
|
static void s_stop(struct seq_file *m, void *p)
|
|
__releases(&vmap_area_lock)
|
|
__releases(&vmap_purge_lock)
|
|
{
|
|
spin_unlock(&vmap_area_lock);
|
|
mutex_unlock(&vmap_purge_lock);
|
|
}
|
|
|
|
static void show_numa_info(struct seq_file *m, struct vm_struct *v)
|
|
{
|
|
if (IS_ENABLED(CONFIG_NUMA)) {
|
|
unsigned int nr, *counters = m->private;
|
|
|
|
if (!counters)
|
|
return;
|
|
|
|
if (v->flags & VM_UNINITIALIZED)
|
|
return;
|
|
/* Pair with smp_wmb() in clear_vm_uninitialized_flag() */
|
|
smp_rmb();
|
|
|
|
memset(counters, 0, nr_node_ids * sizeof(unsigned int));
|
|
|
|
for (nr = 0; nr < v->nr_pages; nr++)
|
|
counters[page_to_nid(v->pages[nr])]++;
|
|
|
|
for_each_node_state(nr, N_HIGH_MEMORY)
|
|
if (counters[nr])
|
|
seq_printf(m, " N%u=%u", nr, counters[nr]);
|
|
}
|
|
}
|
|
|
|
static void show_purge_info(struct seq_file *m)
|
|
{
|
|
struct vmap_area *va;
|
|
|
|
spin_lock(&purge_vmap_area_lock);
|
|
list_for_each_entry(va, &purge_vmap_area_list, list) {
|
|
seq_printf(m, "0x%pK-0x%pK %7ld unpurged vm_area\n",
|
|
(void *)va->va_start, (void *)va->va_end,
|
|
va->va_end - va->va_start);
|
|
}
|
|
spin_unlock(&purge_vmap_area_lock);
|
|
}
|
|
|
|
static int s_show(struct seq_file *m, void *p)
|
|
{
|
|
struct vmap_area *va;
|
|
struct vm_struct *v;
|
|
|
|
va = list_entry(p, struct vmap_area, list);
|
|
|
|
/*
|
|
* s_show can encounter race with remove_vm_area, !vm on behalf
|
|
* of vmap area is being tear down or vm_map_ram allocation.
|
|
*/
|
|
if (!va->vm) {
|
|
seq_printf(m, "0x%pK-0x%pK %7ld vm_map_ram\n",
|
|
(void *)va->va_start, (void *)va->va_end,
|
|
va->va_end - va->va_start);
|
|
|
|
return 0;
|
|
}
|
|
|
|
v = va->vm;
|
|
|
|
seq_printf(m, "0x%pK-0x%pK %7ld",
|
|
v->addr, v->addr + v->size, v->size);
|
|
|
|
if (v->caller)
|
|
seq_printf(m, " %pS", v->caller);
|
|
|
|
if (v->nr_pages)
|
|
seq_printf(m, " pages=%d", v->nr_pages);
|
|
|
|
if (v->phys_addr)
|
|
seq_printf(m, " phys=%pa", &v->phys_addr);
|
|
|
|
if (v->flags & VM_IOREMAP)
|
|
seq_puts(m, " ioremap");
|
|
|
|
if (v->flags & VM_ALLOC)
|
|
seq_puts(m, " vmalloc");
|
|
|
|
if (v->flags & VM_MAP)
|
|
seq_puts(m, " vmap");
|
|
|
|
if (v->flags & VM_USERMAP)
|
|
seq_puts(m, " user");
|
|
|
|
if (v->flags & VM_DMA_COHERENT)
|
|
seq_puts(m, " dma-coherent");
|
|
|
|
if (is_vmalloc_addr(v->pages))
|
|
seq_puts(m, " vpages");
|
|
|
|
show_numa_info(m, v);
|
|
seq_putc(m, '\n');
|
|
|
|
/*
|
|
* As a final step, dump "unpurged" areas.
|
|
*/
|
|
if (list_is_last(&va->list, &vmap_area_list))
|
|
show_purge_info(m);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct seq_operations vmalloc_op = {
|
|
.start = s_start,
|
|
.next = s_next,
|
|
.stop = s_stop,
|
|
.show = s_show,
|
|
};
|
|
|
|
static int __init proc_vmalloc_init(void)
|
|
{
|
|
if (IS_ENABLED(CONFIG_NUMA))
|
|
proc_create_seq_private("vmallocinfo", 0400, NULL,
|
|
&vmalloc_op,
|
|
nr_node_ids * sizeof(unsigned int), NULL);
|
|
else
|
|
proc_create_seq("vmallocinfo", 0400, NULL, &vmalloc_op);
|
|
return 0;
|
|
}
|
|
module_init(proc_vmalloc_init);
|
|
|
|
#endif
|