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fc2c22693c
A lockdep reports a possible deadlock in the find_vmap_area_exceed_addr_lock()
function:
============================================
WARNING: possible recursive locking detected
6.9.0-rc1-00060-ged3ccc57b108-dirty #6140 Not tainted
--------------------------------------------
drgn/455 is trying to acquire lock:
ffff0000c00131d0 (&vn->busy.lock/1){+.+.}-{2:2}, at: find_vmap_area_exceed_addr_lock+0x64/0x124
but task is already holding lock:
ffff0000c0011878 (&vn->busy.lock/1){+.+.}-{2:2}, at: find_vmap_area_exceed_addr_lock+0x64/0x124
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&vn->busy.lock/1);
lock(&vn->busy.lock/1);
*** DEADLOCK ***
indeed it can happen if the find_vmap_area_exceed_addr_lock() gets called
concurrently because it tries to acquire two nodes locks. It was done to
prevent removing a lowest VA found on a previous step.
To address this a lowest VA is found first without holding a node lock
where it resides. As a last step we check if a VA still there because it
can go away, if removed, proceed with next lowest.
[akpm@linux-foundation.org: fix comment typos, per Baoquan]
Link: https://lkml.kernel.org/r/20240328140330.4747-1-urezki@gmail.com
Fixes: 53becf32ae
("mm: vmalloc: support multiple nodes in vread_iter")
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Tested-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Omar Sandoval <osandov@fb.com>
Reported-by: Jens Axboe <axboe@kernel.dk>
Cc: Baoquan He <bhe@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
5133 lines
131 KiB
C
5133 lines
131 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/io.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/memcontrol.h>
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#include <linux/llist.h>
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#include <linux/uio.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/pgtable.h>
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#include <linux/hugetlb.h>
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#include <linux/sched/mm.h>
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#include <asm/tlbflush.h>
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#include <asm/shmparam.h>
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#define CREATE_TRACE_POINTS
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#include <trace/events/vmalloc.h>
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#include "internal.h"
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#include "pgalloc-track.h"
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#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
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static unsigned int __ro_after_init ioremap_max_page_shift = BITS_PER_LONG - 1;
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static int __init set_nohugeiomap(char *str)
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{
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ioremap_max_page_shift = PAGE_SHIFT;
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return 0;
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}
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early_param("nohugeiomap", set_nohugeiomap);
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#else /* CONFIG_HAVE_ARCH_HUGE_VMAP */
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static const unsigned int ioremap_max_page_shift = PAGE_SHIFT;
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#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
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#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
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static bool __ro_after_init vmap_allow_huge = true;
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static int __init set_nohugevmalloc(char *str)
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{
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vmap_allow_huge = false;
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return 0;
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}
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early_param("nohugevmalloc", set_nohugevmalloc);
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#else /* CONFIG_HAVE_ARCH_HUGE_VMALLOC */
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static const bool vmap_allow_huge = false;
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#endif /* CONFIG_HAVE_ARCH_HUGE_VMALLOC */
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bool is_vmalloc_addr(const void *x)
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{
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unsigned long addr = (unsigned long)kasan_reset_tag(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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/*** Page table manipulation functions ***/
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static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
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phys_addr_t phys_addr, pgprot_t prot,
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unsigned int max_page_shift, pgtbl_mod_mask *mask)
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{
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pte_t *pte;
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u64 pfn;
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unsigned long size = PAGE_SIZE;
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pfn = phys_addr >> PAGE_SHIFT;
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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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BUG_ON(!pte_none(ptep_get(pte)));
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#ifdef CONFIG_HUGETLB_PAGE
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size = arch_vmap_pte_range_map_size(addr, end, pfn, max_page_shift);
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if (size != PAGE_SIZE) {
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pte_t entry = pfn_pte(pfn, prot);
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entry = arch_make_huge_pte(entry, ilog2(size), 0);
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set_huge_pte_at(&init_mm, addr, pte, entry, size);
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pfn += PFN_DOWN(size);
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continue;
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}
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#endif
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set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
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pfn++;
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} while (pte += PFN_DOWN(size), addr += 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_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
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phys_addr_t phys_addr, pgprot_t prot,
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unsigned int max_page_shift)
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{
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if (max_page_shift < PMD_SHIFT)
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return 0;
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if (!arch_vmap_pmd_supported(prot))
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return 0;
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if ((end - addr) != PMD_SIZE)
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return 0;
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if (!IS_ALIGNED(addr, PMD_SIZE))
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return 0;
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if (!IS_ALIGNED(phys_addr, PMD_SIZE))
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return 0;
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if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr))
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return 0;
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return pmd_set_huge(pmd, phys_addr, prot);
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}
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static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
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phys_addr_t phys_addr, pgprot_t prot,
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unsigned int max_page_shift, 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_try_huge_pmd(pmd, addr, next, phys_addr, prot,
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max_page_shift)) {
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*mask |= PGTBL_PMD_MODIFIED;
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continue;
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}
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if (vmap_pte_range(pmd, addr, next, phys_addr, prot, max_page_shift, mask))
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return -ENOMEM;
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} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
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return 0;
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}
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static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
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phys_addr_t phys_addr, pgprot_t prot,
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unsigned int max_page_shift)
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{
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if (max_page_shift < PUD_SHIFT)
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return 0;
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if (!arch_vmap_pud_supported(prot))
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return 0;
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if ((end - addr) != PUD_SIZE)
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return 0;
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if (!IS_ALIGNED(addr, PUD_SIZE))
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return 0;
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if (!IS_ALIGNED(phys_addr, PUD_SIZE))
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return 0;
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if (pud_present(*pud) && !pud_free_pmd_page(pud, addr))
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return 0;
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return pud_set_huge(pud, phys_addr, prot);
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}
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static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
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phys_addr_t phys_addr, pgprot_t prot,
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unsigned int max_page_shift, 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_try_huge_pud(pud, addr, next, phys_addr, prot,
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max_page_shift)) {
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*mask |= PGTBL_PUD_MODIFIED;
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continue;
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}
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if (vmap_pmd_range(pud, addr, next, phys_addr, prot,
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max_page_shift, mask))
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return -ENOMEM;
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} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
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return 0;
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}
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static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
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phys_addr_t phys_addr, pgprot_t prot,
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unsigned int max_page_shift)
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{
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if (max_page_shift < P4D_SHIFT)
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return 0;
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if (!arch_vmap_p4d_supported(prot))
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return 0;
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if ((end - addr) != P4D_SIZE)
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return 0;
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if (!IS_ALIGNED(addr, P4D_SIZE))
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return 0;
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if (!IS_ALIGNED(phys_addr, P4D_SIZE))
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return 0;
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if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr))
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return 0;
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return p4d_set_huge(p4d, phys_addr, prot);
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}
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static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
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phys_addr_t phys_addr, pgprot_t prot,
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unsigned int max_page_shift, 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_try_huge_p4d(p4d, addr, next, phys_addr, prot,
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max_page_shift)) {
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*mask |= PGTBL_P4D_MODIFIED;
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continue;
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}
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if (vmap_pud_range(p4d, addr, next, phys_addr, prot,
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max_page_shift, mask))
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return -ENOMEM;
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} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
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return 0;
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}
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static int vmap_range_noflush(unsigned long addr, unsigned long end,
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phys_addr_t phys_addr, pgprot_t prot,
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unsigned int max_page_shift)
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{
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pgd_t *pgd;
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unsigned long start;
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unsigned long next;
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int err;
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pgtbl_mod_mask mask = 0;
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might_sleep();
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BUG_ON(addr >= end);
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start = addr;
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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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err = vmap_p4d_range(pgd, addr, next, phys_addr, prot,
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max_page_shift, &mask);
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if (err)
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break;
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} while (pgd++, phys_addr += (next - addr), 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 err;
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}
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int vmap_page_range(unsigned long addr, unsigned long end,
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phys_addr_t phys_addr, pgprot_t prot)
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{
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int err;
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err = vmap_range_noflush(addr, end, phys_addr, pgprot_nx(prot),
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ioremap_max_page_shift);
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flush_cache_vmap(addr, end);
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if (!err)
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err = kmsan_ioremap_page_range(addr, end, phys_addr, prot,
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ioremap_max_page_shift);
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return err;
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}
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int ioremap_page_range(unsigned long addr, unsigned long end,
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phys_addr_t phys_addr, pgprot_t prot)
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{
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struct vm_struct *area;
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area = find_vm_area((void *)addr);
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if (!area || !(area->flags & VM_IOREMAP)) {
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WARN_ONCE(1, "vm_area at addr %lx is not marked as VM_IOREMAP\n", addr);
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return -EINVAL;
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}
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if (addr != (unsigned long)area->addr ||
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(void *)end != area->addr + get_vm_area_size(area)) {
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WARN_ONCE(1, "ioremap request [%lx,%lx) doesn't match vm_area [%lx, %lx)\n",
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addr, end, (long)area->addr,
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(long)area->addr + get_vm_area_size(area));
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return -ERANGE;
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}
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return vmap_page_range(addr, end, phys_addr, prot);
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}
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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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p4d = p4d_offset(pgd, addr);
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do {
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next = p4d_addr_end(addr, end);
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p4d_clear_huge(p4d);
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if (p4d_bad(*p4d))
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*mask |= PGTBL_P4D_MODIFIED;
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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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* vunmap_range_noflush is similar to vunmap_range, but does not
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* flush caches or TLBs.
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*
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* The caller is responsible for calling flush_cache_vmap() before calling
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* this function, and flush_tlb_kernel_range after it has returned
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* successfully (and before the addresses are expected to cause a page fault
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* or be re-mapped for something else, if TLB flushes are being delayed or
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* coalesced).
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*
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* This is an internal function only. Do not use outside mm/.
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*/
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void __vunmap_range_noflush(unsigned long start, unsigned long end)
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{
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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);
|
|
} while (pgd++, addr = next, addr != end);
|
|
|
|
if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
|
|
arch_sync_kernel_mappings(start, end);
|
|
}
|
|
|
|
void vunmap_range_noflush(unsigned long start, unsigned long end)
|
|
{
|
|
kmsan_vunmap_range_noflush(start, end);
|
|
__vunmap_range_noflush(start, end);
|
|
}
|
|
|
|
/**
|
|
* vunmap_range - unmap kernel virtual addresses
|
|
* @addr: start of the VM area to unmap
|
|
* @end: end of the VM area to unmap (non-inclusive)
|
|
*
|
|
* Clears any present PTEs in the virtual address range, flushes TLBs and
|
|
* caches. Any subsequent access to the address before it has been re-mapped
|
|
* is a kernel bug.
|
|
*/
|
|
void vunmap_range(unsigned long addr, unsigned long end)
|
|
{
|
|
flush_cache_vunmap(addr, end);
|
|
vunmap_range_noflush(addr, end);
|
|
flush_tlb_kernel_range(addr, end);
|
|
}
|
|
|
|
static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
|
|
unsigned long end, pgprot_t prot, struct page **pages, int *nr,
|
|
pgtbl_mod_mask *mask)
|
|
{
|
|
pte_t *pte;
|
|
|
|
/*
|
|
* nr is a running index into the array which helps higher level
|
|
* callers keep track of where we're up to.
|
|
*/
|
|
|
|
pte = pte_alloc_kernel_track(pmd, addr, mask);
|
|
if (!pte)
|
|
return -ENOMEM;
|
|
do {
|
|
struct page *page = pages[*nr];
|
|
|
|
if (WARN_ON(!pte_none(ptep_get(pte))))
|
|
return -EBUSY;
|
|
if (WARN_ON(!page))
|
|
return -ENOMEM;
|
|
if (WARN_ON(!pfn_valid(page_to_pfn(page))))
|
|
return -EINVAL;
|
|
|
|
set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
|
|
(*nr)++;
|
|
} while (pte++, addr += PAGE_SIZE, addr != end);
|
|
*mask |= PGTBL_PTE_MODIFIED;
|
|
return 0;
|
|
}
|
|
|
|
static int vmap_pages_pmd_range(pud_t *pud, unsigned long addr,
|
|
unsigned long end, pgprot_t prot, struct page **pages, int *nr,
|
|
pgtbl_mod_mask *mask)
|
|
{
|
|
pmd_t *pmd;
|
|
unsigned long next;
|
|
|
|
pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
|
|
if (!pmd)
|
|
return -ENOMEM;
|
|
do {
|
|
next = pmd_addr_end(addr, end);
|
|
if (vmap_pages_pte_range(pmd, addr, next, prot, pages, nr, mask))
|
|
return -ENOMEM;
|
|
} while (pmd++, addr = next, addr != end);
|
|
return 0;
|
|
}
|
|
|
|
static int vmap_pages_pud_range(p4d_t *p4d, unsigned long addr,
|
|
unsigned long end, pgprot_t prot, struct page **pages, int *nr,
|
|
pgtbl_mod_mask *mask)
|
|
{
|
|
pud_t *pud;
|
|
unsigned long next;
|
|
|
|
pud = pud_alloc_track(&init_mm, p4d, addr, mask);
|
|
if (!pud)
|
|
return -ENOMEM;
|
|
do {
|
|
next = pud_addr_end(addr, end);
|
|
if (vmap_pages_pmd_range(pud, addr, next, prot, pages, nr, mask))
|
|
return -ENOMEM;
|
|
} while (pud++, addr = next, addr != end);
|
|
return 0;
|
|
}
|
|
|
|
static int vmap_pages_p4d_range(pgd_t *pgd, unsigned long addr,
|
|
unsigned long end, pgprot_t prot, struct page **pages, int *nr,
|
|
pgtbl_mod_mask *mask)
|
|
{
|
|
p4d_t *p4d;
|
|
unsigned long next;
|
|
|
|
p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
|
|
if (!p4d)
|
|
return -ENOMEM;
|
|
do {
|
|
next = p4d_addr_end(addr, end);
|
|
if (vmap_pages_pud_range(p4d, addr, next, prot, pages, nr, mask))
|
|
return -ENOMEM;
|
|
} while (p4d++, addr = next, addr != end);
|
|
return 0;
|
|
}
|
|
|
|
static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end,
|
|
pgprot_t prot, struct page **pages)
|
|
{
|
|
unsigned long start = addr;
|
|
pgd_t *pgd;
|
|
unsigned long next;
|
|
int err = 0;
|
|
int nr = 0;
|
|
pgtbl_mod_mask mask = 0;
|
|
|
|
BUG_ON(addr >= end);
|
|
pgd = pgd_offset_k(addr);
|
|
do {
|
|
next = pgd_addr_end(addr, end);
|
|
if (pgd_bad(*pgd))
|
|
mask |= PGTBL_PGD_MODIFIED;
|
|
err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, &mask);
|
|
if (err)
|
|
return err;
|
|
} while (pgd++, addr = next, addr != end);
|
|
|
|
if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
|
|
arch_sync_kernel_mappings(start, end);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* vmap_pages_range_noflush is similar to vmap_pages_range, but does not
|
|
* flush caches.
|
|
*
|
|
* The caller is responsible for calling flush_cache_vmap() after this
|
|
* function returns successfully and before the addresses are accessed.
|
|
*
|
|
* This is an internal function only. Do not use outside mm/.
|
|
*/
|
|
int __vmap_pages_range_noflush(unsigned long addr, unsigned long end,
|
|
pgprot_t prot, struct page **pages, unsigned int page_shift)
|
|
{
|
|
unsigned int i, nr = (end - addr) >> PAGE_SHIFT;
|
|
|
|
WARN_ON(page_shift < PAGE_SHIFT);
|
|
|
|
if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMALLOC) ||
|
|
page_shift == PAGE_SHIFT)
|
|
return vmap_small_pages_range_noflush(addr, end, prot, pages);
|
|
|
|
for (i = 0; i < nr; i += 1U << (page_shift - PAGE_SHIFT)) {
|
|
int err;
|
|
|
|
err = vmap_range_noflush(addr, addr + (1UL << page_shift),
|
|
page_to_phys(pages[i]), prot,
|
|
page_shift);
|
|
if (err)
|
|
return err;
|
|
|
|
addr += 1UL << page_shift;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int vmap_pages_range_noflush(unsigned long addr, unsigned long end,
|
|
pgprot_t prot, struct page **pages, unsigned int page_shift)
|
|
{
|
|
int ret = kmsan_vmap_pages_range_noflush(addr, end, prot, pages,
|
|
page_shift);
|
|
|
|
if (ret)
|
|
return ret;
|
|
return __vmap_pages_range_noflush(addr, end, prot, pages, page_shift);
|
|
}
|
|
|
|
/**
|
|
* vmap_pages_range - map pages to a kernel virtual address
|
|
* @addr: start of the VM area to map
|
|
* @end: end of the VM area to map (non-inclusive)
|
|
* @prot: page protection flags to use
|
|
* @pages: pages to map (always PAGE_SIZE pages)
|
|
* @page_shift: maximum shift that the pages may be mapped with, @pages must
|
|
* be aligned and contiguous up to at least this shift.
|
|
*
|
|
* RETURNS:
|
|
* 0 on success, -errno on failure.
|
|
*/
|
|
static int vmap_pages_range(unsigned long addr, unsigned long end,
|
|
pgprot_t prot, struct page **pages, unsigned int page_shift)
|
|
{
|
|
int err;
|
|
|
|
err = vmap_pages_range_noflush(addr, end, prot, pages, page_shift);
|
|
flush_cache_vmap(addr, end);
|
|
return err;
|
|
}
|
|
|
|
static int check_sparse_vm_area(struct vm_struct *area, unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
might_sleep();
|
|
if (WARN_ON_ONCE(area->flags & VM_FLUSH_RESET_PERMS))
|
|
return -EINVAL;
|
|
if (WARN_ON_ONCE(area->flags & VM_NO_GUARD))
|
|
return -EINVAL;
|
|
if (WARN_ON_ONCE(!(area->flags & VM_SPARSE)))
|
|
return -EINVAL;
|
|
if ((end - start) >> PAGE_SHIFT > totalram_pages())
|
|
return -E2BIG;
|
|
if (start < (unsigned long)area->addr ||
|
|
(void *)end > area->addr + get_vm_area_size(area))
|
|
return -ERANGE;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* vm_area_map_pages - map pages inside given sparse vm_area
|
|
* @area: vm_area
|
|
* @start: start address inside vm_area
|
|
* @end: end address inside vm_area
|
|
* @pages: pages to map (always PAGE_SIZE pages)
|
|
*/
|
|
int vm_area_map_pages(struct vm_struct *area, unsigned long start,
|
|
unsigned long end, struct page **pages)
|
|
{
|
|
int err;
|
|
|
|
err = check_sparse_vm_area(area, start, end);
|
|
if (err)
|
|
return err;
|
|
|
|
return vmap_pages_range(start, end, PAGE_KERNEL, pages, PAGE_SHIFT);
|
|
}
|
|
|
|
/**
|
|
* vm_area_unmap_pages - unmap pages inside given sparse vm_area
|
|
* @area: vm_area
|
|
* @start: start address inside vm_area
|
|
* @end: end address inside vm_area
|
|
*/
|
|
void vm_area_unmap_pages(struct vm_struct *area, unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
if (check_sparse_vm_area(area, start, end))
|
|
return;
|
|
|
|
vunmap_range(start, end);
|
|
}
|
|
|
|
int is_vmalloc_or_module_addr(const void *x)
|
|
{
|
|
/*
|
|
* ARM, x86-64 and sparc64 put modules in a special place,
|
|
* and fall back on vmalloc() if that fails. Others
|
|
* just put it in the vmalloc space.
|
|
*/
|
|
#if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
|
|
unsigned long addr = (unsigned long)kasan_reset_tag(x);
|
|
if (addr >= MODULES_VADDR && addr < MODULES_END)
|
|
return 1;
|
|
#endif
|
|
return is_vmalloc_addr(x);
|
|
}
|
|
EXPORT_SYMBOL_GPL(is_vmalloc_or_module_addr);
|
|
|
|
/*
|
|
* Walk a vmap address to the struct page it maps. Huge vmap mappings will
|
|
* return the tail page that corresponds to the base page address, which
|
|
* matches small vmap mappings.
|
|
*/
|
|
struct page *vmalloc_to_page(const void *vmalloc_addr)
|
|
{
|
|
unsigned long addr = (unsigned long) vmalloc_addr;
|
|
struct page *page = NULL;
|
|
pgd_t *pgd = pgd_offset_k(addr);
|
|
p4d_t *p4d;
|
|
pud_t *pud;
|
|
pmd_t *pmd;
|
|
pte_t *ptep, pte;
|
|
|
|
/*
|
|
* XXX we might need to change this if we add VIRTUAL_BUG_ON for
|
|
* architectures that do not vmalloc module space
|
|
*/
|
|
VIRTUAL_BUG_ON(!is_vmalloc_or_module_addr(vmalloc_addr));
|
|
|
|
if (pgd_none(*pgd))
|
|
return NULL;
|
|
if (WARN_ON_ONCE(pgd_leaf(*pgd)))
|
|
return NULL; /* XXX: no allowance for huge pgd */
|
|
if (WARN_ON_ONCE(pgd_bad(*pgd)))
|
|
return NULL;
|
|
|
|
p4d = p4d_offset(pgd, addr);
|
|
if (p4d_none(*p4d))
|
|
return NULL;
|
|
if (p4d_leaf(*p4d))
|
|
return p4d_page(*p4d) + ((addr & ~P4D_MASK) >> PAGE_SHIFT);
|
|
if (WARN_ON_ONCE(p4d_bad(*p4d)))
|
|
return NULL;
|
|
|
|
pud = pud_offset(p4d, addr);
|
|
if (pud_none(*pud))
|
|
return NULL;
|
|
if (pud_leaf(*pud))
|
|
return pud_page(*pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
|
|
if (WARN_ON_ONCE(pud_bad(*pud)))
|
|
return NULL;
|
|
|
|
pmd = pmd_offset(pud, addr);
|
|
if (pmd_none(*pmd))
|
|
return NULL;
|
|
if (pmd_leaf(*pmd))
|
|
return pmd_page(*pmd) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
|
|
if (WARN_ON_ONCE(pmd_bad(*pmd)))
|
|
return NULL;
|
|
|
|
ptep = pte_offset_kernel(pmd, addr);
|
|
pte = ptep_get(ptep);
|
|
if (pte_present(pte))
|
|
page = pte_page(pte);
|
|
|
|
return page;
|
|
}
|
|
EXPORT_SYMBOL(vmalloc_to_page);
|
|
|
|
/*
|
|
* Map a vmalloc()-space virtual address to the physical page frame number.
|
|
*/
|
|
unsigned long vmalloc_to_pfn(const void *vmalloc_addr)
|
|
{
|
|
return page_to_pfn(vmalloc_to_page(vmalloc_addr));
|
|
}
|
|
EXPORT_SYMBOL(vmalloc_to_pfn);
|
|
|
|
|
|
/*** Global kva allocator ***/
|
|
|
|
#define DEBUG_AUGMENT_PROPAGATE_CHECK 0
|
|
#define DEBUG_AUGMENT_LOWEST_MATCH_CHECK 0
|
|
|
|
|
|
static DEFINE_SPINLOCK(free_vmap_area_lock);
|
|
static bool vmap_initialized __read_mostly;
|
|
|
|
/*
|
|
* This kmem_cache is used for vmap_area objects. Instead of
|
|
* allocating from slab we reuse an object from this cache to
|
|
* make things faster. Especially in "no edge" splitting of
|
|
* free block.
|
|
*/
|
|
static struct kmem_cache *vmap_area_cachep;
|
|
|
|
/*
|
|
* This linked list is used in pair with free_vmap_area_root.
|
|
* It gives O(1) access to prev/next to perform fast coalescing.
|
|
*/
|
|
static LIST_HEAD(free_vmap_area_list);
|
|
|
|
/*
|
|
* This augment red-black tree represents the free vmap space.
|
|
* All vmap_area objects in this tree are sorted by va->va_start
|
|
* address. It is used for allocation and merging when a vmap
|
|
* object is released.
|
|
*
|
|
* Each vmap_area node contains a maximum available free block
|
|
* of its sub-tree, right or left. Therefore it is possible to
|
|
* find a lowest match of free area.
|
|
*/
|
|
static struct rb_root free_vmap_area_root = RB_ROOT;
|
|
|
|
/*
|
|
* Preload a CPU with one object for "no edge" split case. The
|
|
* aim is to get rid of allocations from the atomic context, thus
|
|
* to use more permissive allocation masks.
|
|
*/
|
|
static DEFINE_PER_CPU(struct vmap_area *, ne_fit_preload_node);
|
|
|
|
/*
|
|
* This structure defines a single, solid model where a list and
|
|
* rb-tree are part of one entity protected by the lock. Nodes are
|
|
* sorted in ascending order, thus for O(1) access to left/right
|
|
* neighbors a list is used as well as for sequential traversal.
|
|
*/
|
|
struct rb_list {
|
|
struct rb_root root;
|
|
struct list_head head;
|
|
spinlock_t lock;
|
|
};
|
|
|
|
/*
|
|
* A fast size storage contains VAs up to 1M size. A pool consists
|
|
* of linked between each other ready to go VAs of certain sizes.
|
|
* An index in the pool-array corresponds to number of pages + 1.
|
|
*/
|
|
#define MAX_VA_SIZE_PAGES 256
|
|
|
|
struct vmap_pool {
|
|
struct list_head head;
|
|
unsigned long len;
|
|
};
|
|
|
|
/*
|
|
* An effective vmap-node logic. Users make use of nodes instead
|
|
* of a global heap. It allows to balance an access and mitigate
|
|
* contention.
|
|
*/
|
|
static struct vmap_node {
|
|
/* Simple size segregated storage. */
|
|
struct vmap_pool pool[MAX_VA_SIZE_PAGES];
|
|
spinlock_t pool_lock;
|
|
bool skip_populate;
|
|
|
|
/* Bookkeeping data of this node. */
|
|
struct rb_list busy;
|
|
struct rb_list lazy;
|
|
|
|
/*
|
|
* Ready-to-free areas.
|
|
*/
|
|
struct list_head purge_list;
|
|
struct work_struct purge_work;
|
|
unsigned long nr_purged;
|
|
} single;
|
|
|
|
/*
|
|
* Initial setup consists of one single node, i.e. a balancing
|
|
* is fully disabled. Later on, after vmap is initialized these
|
|
* parameters are updated based on a system capacity.
|
|
*/
|
|
static struct vmap_node *vmap_nodes = &single;
|
|
static __read_mostly unsigned int nr_vmap_nodes = 1;
|
|
static __read_mostly unsigned int vmap_zone_size = 1;
|
|
|
|
static inline unsigned int
|
|
addr_to_node_id(unsigned long addr)
|
|
{
|
|
return (addr / vmap_zone_size) % nr_vmap_nodes;
|
|
}
|
|
|
|
static inline struct vmap_node *
|
|
addr_to_node(unsigned long addr)
|
|
{
|
|
return &vmap_nodes[addr_to_node_id(addr)];
|
|
}
|
|
|
|
static inline struct vmap_node *
|
|
id_to_node(unsigned int id)
|
|
{
|
|
return &vmap_nodes[id % nr_vmap_nodes];
|
|
}
|
|
|
|
/*
|
|
* We use the value 0 to represent "no node", that is why
|
|
* an encoded value will be the node-id incremented by 1.
|
|
* It is always greater then 0. A valid node_id which can
|
|
* be encoded is [0:nr_vmap_nodes - 1]. If a passed node_id
|
|
* is not valid 0 is returned.
|
|
*/
|
|
static unsigned int
|
|
encode_vn_id(unsigned int node_id)
|
|
{
|
|
/* Can store U8_MAX [0:254] nodes. */
|
|
if (node_id < nr_vmap_nodes)
|
|
return (node_id + 1) << BITS_PER_BYTE;
|
|
|
|
/* Warn and no node encoded. */
|
|
WARN_ONCE(1, "Encode wrong node id (%u)\n", node_id);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Returns an encoded node-id, the valid range is within
|
|
* [0:nr_vmap_nodes-1] values. Otherwise nr_vmap_nodes is
|
|
* returned if extracted data is wrong.
|
|
*/
|
|
static unsigned int
|
|
decode_vn_id(unsigned int val)
|
|
{
|
|
unsigned int node_id = (val >> BITS_PER_BYTE) - 1;
|
|
|
|
/* Can store U8_MAX [0:254] nodes. */
|
|
if (node_id < nr_vmap_nodes)
|
|
return node_id;
|
|
|
|
/* If it was _not_ zero, warn. */
|
|
WARN_ONCE(node_id != UINT_MAX,
|
|
"Decode wrong node id (%d)\n", node_id);
|
|
|
|
return nr_vmap_nodes;
|
|
}
|
|
|
|
static bool
|
|
is_vn_id_valid(unsigned int node_id)
|
|
{
|
|
if (node_id < nr_vmap_nodes)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
static __always_inline unsigned long
|
|
va_size(struct vmap_area *va)
|
|
{
|
|
return (va->va_end - va->va_start);
|
|
}
|
|
|
|
static __always_inline unsigned long
|
|
get_subtree_max_size(struct rb_node *node)
|
|
{
|
|
struct vmap_area *va;
|
|
|
|
va = rb_entry_safe(node, struct vmap_area, rb_node);
|
|
return va ? va->subtree_max_size : 0;
|
|
}
|
|
|
|
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 reclaim_and_purge_vmap_areas(void);
|
|
static BLOCKING_NOTIFIER_HEAD(vmap_notify_list);
|
|
static void drain_vmap_area_work(struct work_struct *work);
|
|
static DECLARE_WORK(drain_vmap_work, drain_vmap_area_work);
|
|
|
|
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_root *root)
|
|
{
|
|
struct rb_node *n = root->rb_node;
|
|
|
|
addr = (unsigned long)kasan_reset_tag((void *)addr);
|
|
|
|
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;
|
|
}
|
|
|
|
/* Look up the first VA which satisfies addr < va_end, NULL if none. */
|
|
static struct vmap_area *
|
|
__find_vmap_area_exceed_addr(unsigned long addr, struct rb_root *root)
|
|
{
|
|
struct vmap_area *va = NULL;
|
|
struct rb_node *n = root->rb_node;
|
|
|
|
addr = (unsigned long)kasan_reset_tag((void *)addr);
|
|
|
|
while (n) {
|
|
struct vmap_area *tmp;
|
|
|
|
tmp = rb_entry(n, struct vmap_area, rb_node);
|
|
if (tmp->va_end > addr) {
|
|
va = tmp;
|
|
if (tmp->va_start <= addr)
|
|
break;
|
|
|
|
n = n->rb_left;
|
|
} else
|
|
n = n->rb_right;
|
|
}
|
|
|
|
return va;
|
|
}
|
|
|
|
/*
|
|
* Returns a node where a first VA, that satisfies addr < va_end, resides.
|
|
* If success, a node is locked. A user is responsible to unlock it when a
|
|
* VA is no longer needed to be accessed.
|
|
*
|
|
* Returns NULL if nothing found.
|
|
*/
|
|
static struct vmap_node *
|
|
find_vmap_area_exceed_addr_lock(unsigned long addr, struct vmap_area **va)
|
|
{
|
|
unsigned long va_start_lowest;
|
|
struct vmap_node *vn;
|
|
int i;
|
|
|
|
repeat:
|
|
for (i = 0, va_start_lowest = 0; i < nr_vmap_nodes; i++) {
|
|
vn = &vmap_nodes[i];
|
|
|
|
spin_lock(&vn->busy.lock);
|
|
*va = __find_vmap_area_exceed_addr(addr, &vn->busy.root);
|
|
|
|
if (*va)
|
|
if (!va_start_lowest || (*va)->va_start < va_start_lowest)
|
|
va_start_lowest = (*va)->va_start;
|
|
spin_unlock(&vn->busy.lock);
|
|
}
|
|
|
|
/*
|
|
* Check if found VA exists, it might have gone away. In this case we
|
|
* repeat the search because a VA has been removed concurrently and we
|
|
* need to proceed to the next one, which is a rare case.
|
|
*/
|
|
if (va_start_lowest) {
|
|
vn = addr_to_node(va_start_lowest);
|
|
|
|
spin_lock(&vn->busy.lock);
|
|
*va = __find_vmap_area(va_start_lowest, &vn->busy.root);
|
|
|
|
if (*va)
|
|
return vn;
|
|
|
|
spin_unlock(&vn->busy.lock);
|
|
goto repeat;
|
|
}
|
|
|
|
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_end <= tmp_va->va_start)
|
|
link = &(*link)->rb_left;
|
|
else if (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, bool augment)
|
|
{
|
|
/*
|
|
* 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 (augment) {
|
|
/*
|
|
* 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 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
|
|
link_va(struct vmap_area *va, struct rb_root *root,
|
|
struct rb_node *parent, struct rb_node **link,
|
|
struct list_head *head)
|
|
{
|
|
__link_va(va, root, parent, link, head, false);
|
|
}
|
|
|
|
static __always_inline void
|
|
link_va_augment(struct vmap_area *va, struct rb_root *root,
|
|
struct rb_node *parent, struct rb_node **link,
|
|
struct list_head *head)
|
|
{
|
|
__link_va(va, root, parent, link, head, true);
|
|
}
|
|
|
|
static __always_inline void
|
|
__unlink_va(struct vmap_area *va, struct rb_root *root, bool augment)
|
|
{
|
|
if (WARN_ON(RB_EMPTY_NODE(&va->rb_node)))
|
|
return;
|
|
|
|
if (augment)
|
|
rb_erase_augmented(&va->rb_node,
|
|
root, &free_vmap_area_rb_augment_cb);
|
|
else
|
|
rb_erase(&va->rb_node, root);
|
|
|
|
list_del_init(&va->list);
|
|
RB_CLEAR_NODE(&va->rb_node);
|
|
}
|
|
|
|
static __always_inline void
|
|
unlink_va(struct vmap_area *va, struct rb_root *root)
|
|
{
|
|
__unlink_va(va, root, false);
|
|
}
|
|
|
|
static __always_inline void
|
|
unlink_va_augment(struct vmap_area *va, struct rb_root *root)
|
|
{
|
|
__unlink_va(va, root, true);
|
|
}
|
|
|
|
#if DEBUG_AUGMENT_PROPAGATE_CHECK
|
|
/*
|
|
* Gets called when remove the node and rotate.
|
|
*/
|
|
static __always_inline unsigned long
|
|
compute_subtree_max_size(struct vmap_area *va)
|
|
{
|
|
return max3(va_size(va),
|
|
get_subtree_max_size(va->rb_node.rb_left),
|
|
get_subtree_max_size(va->rb_node.rb_right));
|
|
}
|
|
|
|
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_augment(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, bool augment)
|
|
{
|
|
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, augment);
|
|
|
|
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, augment);
|
|
|
|
return va;
|
|
}
|
|
|
|
static __always_inline struct vmap_area *
|
|
merge_or_add_vmap_area(struct vmap_area *va,
|
|
struct rb_root *root, struct list_head *head)
|
|
{
|
|
return __merge_or_add_vmap_area(va, root, head, false);
|
|
}
|
|
|
|
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, true);
|
|
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. Please note, with an alignment bigger than PAGE_SIZE,
|
|
* a search length is adjusted to account for worst case alignment
|
|
* overhead.
|
|
*/
|
|
static __always_inline struct vmap_area *
|
|
find_vmap_lowest_match(struct rb_root *root, unsigned long size,
|
|
unsigned long align, unsigned long vstart, bool adjust_search_size)
|
|
{
|
|
struct vmap_area *va;
|
|
struct rb_node *node;
|
|
unsigned long length;
|
|
|
|
/* Start from the root. */
|
|
node = root->rb_node;
|
|
|
|
/* Adjust the search size for alignment overhead. */
|
|
length = adjust_search_size ? size + align - 1 : size;
|
|
|
|
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
|
|
* due to "vstart" restriction or an alignment overhead
|
|
* that is bigger then PAGE_SIZE.
|
|
*/
|
|
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) {
|
|
/*
|
|
* Shift the vstart forward. Please note, we update it with
|
|
* parent's start address adding "1" because we do not want
|
|
* to enter same sub-tree after it has already been checked
|
|
* and no suitable free block found there.
|
|
*/
|
|
vstart = va->va_start + 1;
|
|
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(struct list_head *head, unsigned long size,
|
|
unsigned long align, unsigned long vstart)
|
|
{
|
|
struct vmap_area *va;
|
|
|
|
list_for_each_entry(va, head, list) {
|
|
if (!is_within_this_va(va, size, align, vstart))
|
|
continue;
|
|
|
|
return va;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void
|
|
find_vmap_lowest_match_check(struct rb_root *root, struct list_head *head,
|
|
unsigned long size, unsigned long align)
|
|
{
|
|
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(root, size, align, vstart, false);
|
|
va_2 = find_vmap_lowest_linear_match(head, size, align, 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
|
|
va_clip(struct rb_root *root, struct list_head *head,
|
|
struct vmap_area *va, unsigned long nva_start_addr,
|
|
unsigned long size)
|
|
{
|
|
struct vmap_area *lva = NULL;
|
|
enum fit_type type = classify_va_fit_type(va, nva_start_addr, size);
|
|
|
|
if (type == FL_FIT_TYPE) {
|
|
/*
|
|
* No need to split VA, it fully fits.
|
|
*
|
|
* | |
|
|
* V NVA V
|
|
* |---------------|
|
|
*/
|
|
unlink_va_augment(va, 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, root, head);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static unsigned long
|
|
va_alloc(struct vmap_area *va,
|
|
struct rb_root *root, struct list_head *head,
|
|
unsigned long size, unsigned long align,
|
|
unsigned long vstart, unsigned long vend)
|
|
{
|
|
unsigned long nva_start_addr;
|
|
int ret;
|
|
|
|
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;
|
|
|
|
/* Update the free vmap_area. */
|
|
ret = va_clip(root, head, va, nva_start_addr, size);
|
|
if (WARN_ON_ONCE(ret))
|
|
return vend;
|
|
|
|
return nva_start_addr;
|
|
}
|
|
|
|
/*
|
|
* 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(struct rb_root *root, struct list_head *head,
|
|
unsigned long size, unsigned long align,
|
|
unsigned long vstart, unsigned long vend)
|
|
{
|
|
bool adjust_search_size = true;
|
|
unsigned long nva_start_addr;
|
|
struct vmap_area *va;
|
|
|
|
/*
|
|
* Do not adjust when:
|
|
* a) align <= PAGE_SIZE, because it does not make any sense.
|
|
* All blocks(their start addresses) are at least PAGE_SIZE
|
|
* aligned anyway;
|
|
* b) a short range where a requested size corresponds to exactly
|
|
* specified [vstart:vend] interval and an alignment > PAGE_SIZE.
|
|
* With adjusted search length an allocation would not succeed.
|
|
*/
|
|
if (align <= PAGE_SIZE || (align > PAGE_SIZE && (vend - vstart) == size))
|
|
adjust_search_size = false;
|
|
|
|
va = find_vmap_lowest_match(root, size, align, vstart, adjust_search_size);
|
|
if (unlikely(!va))
|
|
return vend;
|
|
|
|
nva_start_addr = va_alloc(va, root, head, size, align, vstart, vend);
|
|
if (nva_start_addr == vend)
|
|
return vend;
|
|
|
|
#if DEBUG_AUGMENT_LOWEST_MATCH_CHECK
|
|
find_vmap_lowest_match_check(root, head, size, align);
|
|
#endif
|
|
|
|
return nva_start_addr;
|
|
}
|
|
|
|
/*
|
|
* Free a region of KVA allocated by alloc_vmap_area
|
|
*/
|
|
static void free_vmap_area(struct vmap_area *va)
|
|
{
|
|
struct vmap_node *vn = addr_to_node(va->va_start);
|
|
|
|
/*
|
|
* Remove from the busy tree/list.
|
|
*/
|
|
spin_lock(&vn->busy.lock);
|
|
unlink_va(va, &vn->busy.root);
|
|
spin_unlock(&vn->busy.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);
|
|
}
|
|
|
|
static inline void
|
|
preload_this_cpu_lock(spinlock_t *lock, gfp_t gfp_mask, int node)
|
|
{
|
|
struct vmap_area *va = NULL;
|
|
|
|
/*
|
|
* Preload this CPU with one extra vmap_area object. It is used
|
|
* when fit type of free area is NE_FIT_TYPE. It guarantees that
|
|
* a CPU that does an allocation is preloaded.
|
|
*
|
|
* We do it 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.
|
|
*/
|
|
if (!this_cpu_read(ne_fit_preload_node))
|
|
va = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
|
|
|
|
spin_lock(lock);
|
|
|
|
if (va && __this_cpu_cmpxchg(ne_fit_preload_node, NULL, va))
|
|
kmem_cache_free(vmap_area_cachep, va);
|
|
}
|
|
|
|
static struct vmap_pool *
|
|
size_to_va_pool(struct vmap_node *vn, unsigned long size)
|
|
{
|
|
unsigned int idx = (size - 1) / PAGE_SIZE;
|
|
|
|
if (idx < MAX_VA_SIZE_PAGES)
|
|
return &vn->pool[idx];
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static bool
|
|
node_pool_add_va(struct vmap_node *n, struct vmap_area *va)
|
|
{
|
|
struct vmap_pool *vp;
|
|
|
|
vp = size_to_va_pool(n, va_size(va));
|
|
if (!vp)
|
|
return false;
|
|
|
|
spin_lock(&n->pool_lock);
|
|
list_add(&va->list, &vp->head);
|
|
WRITE_ONCE(vp->len, vp->len + 1);
|
|
spin_unlock(&n->pool_lock);
|
|
|
|
return true;
|
|
}
|
|
|
|
static struct vmap_area *
|
|
node_pool_del_va(struct vmap_node *vn, unsigned long size,
|
|
unsigned long align, unsigned long vstart,
|
|
unsigned long vend)
|
|
{
|
|
struct vmap_area *va = NULL;
|
|
struct vmap_pool *vp;
|
|
int err = 0;
|
|
|
|
vp = size_to_va_pool(vn, size);
|
|
if (!vp || list_empty(&vp->head))
|
|
return NULL;
|
|
|
|
spin_lock(&vn->pool_lock);
|
|
if (!list_empty(&vp->head)) {
|
|
va = list_first_entry(&vp->head, struct vmap_area, list);
|
|
|
|
if (IS_ALIGNED(va->va_start, align)) {
|
|
/*
|
|
* Do some sanity check and emit a warning
|
|
* if one of below checks detects an error.
|
|
*/
|
|
err |= (va_size(va) != size);
|
|
err |= (va->va_start < vstart);
|
|
err |= (va->va_end > vend);
|
|
|
|
if (!WARN_ON_ONCE(err)) {
|
|
list_del_init(&va->list);
|
|
WRITE_ONCE(vp->len, vp->len - 1);
|
|
} else {
|
|
va = NULL;
|
|
}
|
|
} else {
|
|
list_move_tail(&va->list, &vp->head);
|
|
va = NULL;
|
|
}
|
|
}
|
|
spin_unlock(&vn->pool_lock);
|
|
|
|
return va;
|
|
}
|
|
|
|
static struct vmap_area *
|
|
node_alloc(unsigned long size, unsigned long align,
|
|
unsigned long vstart, unsigned long vend,
|
|
unsigned long *addr, unsigned int *vn_id)
|
|
{
|
|
struct vmap_area *va;
|
|
|
|
*vn_id = 0;
|
|
*addr = vend;
|
|
|
|
/*
|
|
* Fallback to a global heap if not vmalloc or there
|
|
* is only one node.
|
|
*/
|
|
if (vstart != VMALLOC_START || vend != VMALLOC_END ||
|
|
nr_vmap_nodes == 1)
|
|
return NULL;
|
|
|
|
*vn_id = raw_smp_processor_id() % nr_vmap_nodes;
|
|
va = node_pool_del_va(id_to_node(*vn_id), size, align, vstart, vend);
|
|
*vn_id = encode_vn_id(*vn_id);
|
|
|
|
if (va)
|
|
*addr = va->va_start;
|
|
|
|
return va;
|
|
}
|
|
|
|
/*
|
|
* 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,
|
|
unsigned long va_flags)
|
|
{
|
|
struct vmap_node *vn;
|
|
struct vmap_area *va;
|
|
unsigned long freed;
|
|
unsigned long addr;
|
|
unsigned int vn_id;
|
|
int purged = 0;
|
|
int ret;
|
|
|
|
if (unlikely(!size || offset_in_page(size) || !is_power_of_2(align)))
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
if (unlikely(!vmap_initialized))
|
|
return ERR_PTR(-EBUSY);
|
|
|
|
might_sleep();
|
|
|
|
/*
|
|
* If a VA is obtained from a global heap(if it fails here)
|
|
* it is anyway marked with this "vn_id" so it is returned
|
|
* to this pool's node later. Such way gives a possibility
|
|
* to populate pools based on users demand.
|
|
*
|
|
* On success a ready to go VA is returned.
|
|
*/
|
|
va = node_alloc(size, align, vstart, vend, &addr, &vn_id);
|
|
if (!va) {
|
|
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:
|
|
if (addr == vend) {
|
|
preload_this_cpu_lock(&free_vmap_area_lock, gfp_mask, node);
|
|
addr = __alloc_vmap_area(&free_vmap_area_root, &free_vmap_area_list,
|
|
size, align, vstart, vend);
|
|
spin_unlock(&free_vmap_area_lock);
|
|
}
|
|
|
|
trace_alloc_vmap_area(addr, size, align, vstart, vend, addr == vend);
|
|
|
|
/*
|
|
* If an allocation fails, the "vend" address is
|
|
* returned. Therefore trigger the overflow path.
|
|
*/
|
|
if (unlikely(addr == vend))
|
|
goto overflow;
|
|
|
|
va->va_start = addr;
|
|
va->va_end = addr + size;
|
|
va->vm = NULL;
|
|
va->flags = (va_flags | vn_id);
|
|
|
|
vn = addr_to_node(va->va_start);
|
|
|
|
spin_lock(&vn->busy.lock);
|
|
insert_vmap_area(va, &vn->busy.root, &vn->busy.head);
|
|
spin_unlock(&vn->busy.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) {
|
|
reclaim_and_purge_vmap_areas();
|
|
purged = 1;
|
|
goto retry;
|
|
}
|
|
|
|
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 critical section protected
|
|
* by this lock, 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);
|
|
static cpumask_t purge_nodes;
|
|
|
|
static void
|
|
reclaim_list_global(struct list_head *head)
|
|
{
|
|
struct vmap_area *va, *n;
|
|
|
|
if (list_empty(head))
|
|
return;
|
|
|
|
spin_lock(&free_vmap_area_lock);
|
|
list_for_each_entry_safe(va, n, head, list)
|
|
merge_or_add_vmap_area_augment(va,
|
|
&free_vmap_area_root, &free_vmap_area_list);
|
|
spin_unlock(&free_vmap_area_lock);
|
|
}
|
|
|
|
static void
|
|
decay_va_pool_node(struct vmap_node *vn, bool full_decay)
|
|
{
|
|
struct vmap_area *va, *nva;
|
|
struct list_head decay_list;
|
|
struct rb_root decay_root;
|
|
unsigned long n_decay;
|
|
int i;
|
|
|
|
decay_root = RB_ROOT;
|
|
INIT_LIST_HEAD(&decay_list);
|
|
|
|
for (i = 0; i < MAX_VA_SIZE_PAGES; i++) {
|
|
struct list_head tmp_list;
|
|
|
|
if (list_empty(&vn->pool[i].head))
|
|
continue;
|
|
|
|
INIT_LIST_HEAD(&tmp_list);
|
|
|
|
/* Detach the pool, so no-one can access it. */
|
|
spin_lock(&vn->pool_lock);
|
|
list_replace_init(&vn->pool[i].head, &tmp_list);
|
|
spin_unlock(&vn->pool_lock);
|
|
|
|
if (full_decay)
|
|
WRITE_ONCE(vn->pool[i].len, 0);
|
|
|
|
/* Decay a pool by ~25% out of left objects. */
|
|
n_decay = vn->pool[i].len >> 2;
|
|
|
|
list_for_each_entry_safe(va, nva, &tmp_list, list) {
|
|
list_del_init(&va->list);
|
|
merge_or_add_vmap_area(va, &decay_root, &decay_list);
|
|
|
|
if (!full_decay) {
|
|
WRITE_ONCE(vn->pool[i].len, vn->pool[i].len - 1);
|
|
|
|
if (!--n_decay)
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Attach the pool back if it has been partly decayed.
|
|
* Please note, it is supposed that nobody(other contexts)
|
|
* can populate the pool therefore a simple list replace
|
|
* operation takes place here.
|
|
*/
|
|
if (!full_decay && !list_empty(&tmp_list)) {
|
|
spin_lock(&vn->pool_lock);
|
|
list_replace_init(&tmp_list, &vn->pool[i].head);
|
|
spin_unlock(&vn->pool_lock);
|
|
}
|
|
}
|
|
|
|
reclaim_list_global(&decay_list);
|
|
}
|
|
|
|
static void purge_vmap_node(struct work_struct *work)
|
|
{
|
|
struct vmap_node *vn = container_of(work,
|
|
struct vmap_node, purge_work);
|
|
struct vmap_area *va, *n_va;
|
|
LIST_HEAD(local_list);
|
|
|
|
vn->nr_purged = 0;
|
|
|
|
list_for_each_entry_safe(va, n_va, &vn->purge_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;
|
|
unsigned int vn_id = decode_vn_id(va->flags);
|
|
|
|
list_del_init(&va->list);
|
|
|
|
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);
|
|
vn->nr_purged++;
|
|
|
|
if (is_vn_id_valid(vn_id) && !vn->skip_populate)
|
|
if (node_pool_add_va(vn, va))
|
|
continue;
|
|
|
|
/* Go back to global. */
|
|
list_add(&va->list, &local_list);
|
|
}
|
|
|
|
reclaim_list_global(&local_list);
|
|
}
|
|
|
|
/*
|
|
* Purges all lazily-freed vmap areas.
|
|
*/
|
|
static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end,
|
|
bool full_pool_decay)
|
|
{
|
|
unsigned long nr_purged_areas = 0;
|
|
unsigned int nr_purge_helpers;
|
|
unsigned int nr_purge_nodes;
|
|
struct vmap_node *vn;
|
|
int i;
|
|
|
|
lockdep_assert_held(&vmap_purge_lock);
|
|
|
|
/*
|
|
* Use cpumask to mark which node has to be processed.
|
|
*/
|
|
purge_nodes = CPU_MASK_NONE;
|
|
|
|
for (i = 0; i < nr_vmap_nodes; i++) {
|
|
vn = &vmap_nodes[i];
|
|
|
|
INIT_LIST_HEAD(&vn->purge_list);
|
|
vn->skip_populate = full_pool_decay;
|
|
decay_va_pool_node(vn, full_pool_decay);
|
|
|
|
if (RB_EMPTY_ROOT(&vn->lazy.root))
|
|
continue;
|
|
|
|
spin_lock(&vn->lazy.lock);
|
|
WRITE_ONCE(vn->lazy.root.rb_node, NULL);
|
|
list_replace_init(&vn->lazy.head, &vn->purge_list);
|
|
spin_unlock(&vn->lazy.lock);
|
|
|
|
start = min(start, list_first_entry(&vn->purge_list,
|
|
struct vmap_area, list)->va_start);
|
|
|
|
end = max(end, list_last_entry(&vn->purge_list,
|
|
struct vmap_area, list)->va_end);
|
|
|
|
cpumask_set_cpu(i, &purge_nodes);
|
|
}
|
|
|
|
nr_purge_nodes = cpumask_weight(&purge_nodes);
|
|
if (nr_purge_nodes > 0) {
|
|
flush_tlb_kernel_range(start, end);
|
|
|
|
/* One extra worker is per a lazy_max_pages() full set minus one. */
|
|
nr_purge_helpers = atomic_long_read(&vmap_lazy_nr) / lazy_max_pages();
|
|
nr_purge_helpers = clamp(nr_purge_helpers, 1U, nr_purge_nodes) - 1;
|
|
|
|
for_each_cpu(i, &purge_nodes) {
|
|
vn = &vmap_nodes[i];
|
|
|
|
if (nr_purge_helpers > 0) {
|
|
INIT_WORK(&vn->purge_work, purge_vmap_node);
|
|
|
|
if (cpumask_test_cpu(i, cpu_online_mask))
|
|
schedule_work_on(i, &vn->purge_work);
|
|
else
|
|
schedule_work(&vn->purge_work);
|
|
|
|
nr_purge_helpers--;
|
|
} else {
|
|
vn->purge_work.func = NULL;
|
|
purge_vmap_node(&vn->purge_work);
|
|
nr_purged_areas += vn->nr_purged;
|
|
}
|
|
}
|
|
|
|
for_each_cpu(i, &purge_nodes) {
|
|
vn = &vmap_nodes[i];
|
|
|
|
if (vn->purge_work.func) {
|
|
flush_work(&vn->purge_work);
|
|
nr_purged_areas += vn->nr_purged;
|
|
}
|
|
}
|
|
}
|
|
|
|
trace_purge_vmap_area_lazy(start, end, nr_purged_areas);
|
|
return nr_purged_areas > 0;
|
|
}
|
|
|
|
/*
|
|
* Reclaim vmap areas by purging fragmented blocks and purge_vmap_area_list.
|
|
*/
|
|
static void reclaim_and_purge_vmap_areas(void)
|
|
|
|
{
|
|
mutex_lock(&vmap_purge_lock);
|
|
purge_fragmented_blocks_allcpus();
|
|
__purge_vmap_area_lazy(ULONG_MAX, 0, true);
|
|
mutex_unlock(&vmap_purge_lock);
|
|
}
|
|
|
|
static void drain_vmap_area_work(struct work_struct *work)
|
|
{
|
|
mutex_lock(&vmap_purge_lock);
|
|
__purge_vmap_area_lazy(ULONG_MAX, 0, false);
|
|
mutex_unlock(&vmap_purge_lock);
|
|
}
|
|
|
|
/*
|
|
* Free a vmap area, caller ensuring that the area has been unmapped,
|
|
* unlinked 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_max = lazy_max_pages();
|
|
unsigned long va_start = va->va_start;
|
|
unsigned int vn_id = decode_vn_id(va->flags);
|
|
struct vmap_node *vn;
|
|
unsigned long nr_lazy;
|
|
|
|
if (WARN_ON_ONCE(!list_empty(&va->list)))
|
|
return;
|
|
|
|
nr_lazy = atomic_long_add_return((va->va_end - va->va_start) >>
|
|
PAGE_SHIFT, &vmap_lazy_nr);
|
|
|
|
/*
|
|
* If it was request by a certain node we would like to
|
|
* return it to that node, i.e. its pool for later reuse.
|
|
*/
|
|
vn = is_vn_id_valid(vn_id) ?
|
|
id_to_node(vn_id):addr_to_node(va->va_start);
|
|
|
|
spin_lock(&vn->lazy.lock);
|
|
insert_vmap_area(va, &vn->lazy.root, &vn->lazy.head);
|
|
spin_unlock(&vn->lazy.lock);
|
|
|
|
trace_free_vmap_area_noflush(va_start, nr_lazy, nr_lazy_max);
|
|
|
|
/* After this point, we may free va at any time */
|
|
if (unlikely(nr_lazy > nr_lazy_max))
|
|
schedule_work(&drain_vmap_work);
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
vunmap_range_noflush(va->va_start, va->va_end);
|
|
if (debug_pagealloc_enabled_static())
|
|
flush_tlb_kernel_range(va->va_start, va->va_end);
|
|
|
|
free_vmap_area_noflush(va);
|
|
}
|
|
|
|
struct vmap_area *find_vmap_area(unsigned long addr)
|
|
{
|
|
struct vmap_node *vn;
|
|
struct vmap_area *va;
|
|
int i, j;
|
|
|
|
if (unlikely(!vmap_initialized))
|
|
return NULL;
|
|
|
|
/*
|
|
* An addr_to_node_id(addr) converts an address to a node index
|
|
* where a VA is located. If VA spans several zones and passed
|
|
* addr is not the same as va->va_start, what is not common, we
|
|
* may need to scan extra nodes. See an example:
|
|
*
|
|
* <----va---->
|
|
* -|-----|-----|-----|-----|-
|
|
* 1 2 0 1
|
|
*
|
|
* VA resides in node 1 whereas it spans 1, 2 an 0. If passed
|
|
* addr is within 2 or 0 nodes we should do extra work.
|
|
*/
|
|
i = j = addr_to_node_id(addr);
|
|
do {
|
|
vn = &vmap_nodes[i];
|
|
|
|
spin_lock(&vn->busy.lock);
|
|
va = __find_vmap_area(addr, &vn->busy.root);
|
|
spin_unlock(&vn->busy.lock);
|
|
|
|
if (va)
|
|
return va;
|
|
} while ((i = (i + 1) % nr_vmap_nodes) != j);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static struct vmap_area *find_unlink_vmap_area(unsigned long addr)
|
|
{
|
|
struct vmap_node *vn;
|
|
struct vmap_area *va;
|
|
int i, j;
|
|
|
|
/*
|
|
* Check the comment in the find_vmap_area() about the loop.
|
|
*/
|
|
i = j = addr_to_node_id(addr);
|
|
do {
|
|
vn = &vmap_nodes[i];
|
|
|
|
spin_lock(&vn->busy.lock);
|
|
va = __find_vmap_area(addr, &vn->busy.root);
|
|
if (va)
|
|
unlink_va(va, &vn->busy.root);
|
|
spin_unlock(&vn->busy.lock);
|
|
|
|
if (va)
|
|
return va;
|
|
} while ((i = (i + 1) % nr_vmap_nodes) != j);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*** 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)
|
|
|
|
/*
|
|
* Purge threshold to prevent overeager purging of fragmented blocks for
|
|
* regular operations: Purge if vb->free is less than 1/4 of the capacity.
|
|
*/
|
|
#define VMAP_PURGE_THRESHOLD (VMAP_BBMAP_BITS / 4)
|
|
|
|
#define VMAP_RAM 0x1 /* indicates vm_map_ram area*/
|
|
#define VMAP_BLOCK 0x2 /* mark out the vmap_block sub-type*/
|
|
#define VMAP_FLAGS_MASK 0x3
|
|
|
|
struct vmap_block_queue {
|
|
spinlock_t lock;
|
|
struct list_head free;
|
|
|
|
/*
|
|
* An xarray requires an extra memory dynamically to
|
|
* be allocated. If it is an issue, we can use rb-tree
|
|
* instead.
|
|
*/
|
|
struct xarray vmap_blocks;
|
|
};
|
|
|
|
struct vmap_block {
|
|
spinlock_t lock;
|
|
struct vmap_area *va;
|
|
unsigned long free, dirty;
|
|
DECLARE_BITMAP(used_map, VMAP_BBMAP_BITS);
|
|
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);
|
|
|
|
/*
|
|
* In order to fast access to any "vmap_block" associated with a
|
|
* specific address, we use a hash.
|
|
*
|
|
* A per-cpu vmap_block_queue is used in both ways, to serialize
|
|
* an access to free block chains among CPUs(alloc path) and it
|
|
* also acts as a vmap_block hash(alloc/free paths). It means we
|
|
* overload it, since we already have the per-cpu array which is
|
|
* used as a hash table. When used as a hash a 'cpu' passed to
|
|
* per_cpu() is not actually a CPU but rather a hash index.
|
|
*
|
|
* A hash function is addr_to_vb_xa() which hashes any address
|
|
* to a specific index(in a hash) it belongs to. This then uses a
|
|
* per_cpu() macro to access an array with generated index.
|
|
*
|
|
* An example:
|
|
*
|
|
* CPU_1 CPU_2 CPU_0
|
|
* | | |
|
|
* V V V
|
|
* 0 10 20 30 40 50 60
|
|
* |------|------|------|------|------|------|...<vmap address space>
|
|
* CPU0 CPU1 CPU2 CPU0 CPU1 CPU2
|
|
*
|
|
* - CPU_1 invokes vm_unmap_ram(6), 6 belongs to CPU0 zone, thus
|
|
* it access: CPU0/INDEX0 -> vmap_blocks -> xa_lock;
|
|
*
|
|
* - CPU_2 invokes vm_unmap_ram(11), 11 belongs to CPU1 zone, thus
|
|
* it access: CPU1/INDEX1 -> vmap_blocks -> xa_lock;
|
|
*
|
|
* - CPU_0 invokes vm_unmap_ram(20), 20 belongs to CPU2 zone, thus
|
|
* it access: CPU2/INDEX2 -> vmap_blocks -> xa_lock.
|
|
*
|
|
* This technique almost always avoids lock contention on insert/remove,
|
|
* however xarray spinlocks protect against any contention that remains.
|
|
*/
|
|
static struct xarray *
|
|
addr_to_vb_xa(unsigned long addr)
|
|
{
|
|
int index = (addr / VMAP_BLOCK_SIZE) % num_possible_cpus();
|
|
|
|
return &per_cpu(vmap_block_queue, index).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;
|
|
struct xarray *xa;
|
|
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,
|
|
VMAP_RAM|VMAP_BLOCK);
|
|
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));
|
|
bitmap_zero(vb->used_map, VMAP_BBMAP_BITS);
|
|
vb->free = VMAP_BBMAP_BITS - (1UL << order);
|
|
vb->dirty = 0;
|
|
vb->dirty_min = VMAP_BBMAP_BITS;
|
|
vb->dirty_max = 0;
|
|
bitmap_set(vb->used_map, 0, (1UL << order));
|
|
INIT_LIST_HEAD(&vb->free_list);
|
|
|
|
xa = addr_to_vb_xa(va->va_start);
|
|
vb_idx = addr_to_vb_idx(va->va_start);
|
|
err = xa_insert(xa, vb_idx, vb, gfp_mask);
|
|
if (err) {
|
|
kfree(vb);
|
|
free_vmap_area(va);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
vbq = raw_cpu_ptr(&vmap_block_queue);
|
|
spin_lock(&vbq->lock);
|
|
list_add_tail_rcu(&vb->free_list, &vbq->free);
|
|
spin_unlock(&vbq->lock);
|
|
|
|
return vaddr;
|
|
}
|
|
|
|
static void free_vmap_block(struct vmap_block *vb)
|
|
{
|
|
struct vmap_node *vn;
|
|
struct vmap_block *tmp;
|
|
struct xarray *xa;
|
|
|
|
xa = addr_to_vb_xa(vb->va->va_start);
|
|
tmp = xa_erase(xa, addr_to_vb_idx(vb->va->va_start));
|
|
BUG_ON(tmp != vb);
|
|
|
|
vn = addr_to_node(vb->va->va_start);
|
|
spin_lock(&vn->busy.lock);
|
|
unlink_va(vb->va, &vn->busy.root);
|
|
spin_unlock(&vn->busy.lock);
|
|
|
|
free_vmap_area_noflush(vb->va);
|
|
kfree_rcu(vb, rcu_head);
|
|
}
|
|
|
|
static bool purge_fragmented_block(struct vmap_block *vb,
|
|
struct vmap_block_queue *vbq, struct list_head *purge_list,
|
|
bool force_purge)
|
|
{
|
|
if (vb->free + vb->dirty != VMAP_BBMAP_BITS ||
|
|
vb->dirty == VMAP_BBMAP_BITS)
|
|
return false;
|
|
|
|
/* Don't overeagerly purge usable blocks unless requested */
|
|
if (!(force_purge || vb->free < VMAP_PURGE_THRESHOLD))
|
|
return false;
|
|
|
|
/* prevent further allocs after releasing lock */
|
|
WRITE_ONCE(vb->free, 0);
|
|
/* prevent purging it again */
|
|
WRITE_ONCE(vb->dirty, VMAP_BBMAP_BITS);
|
|
vb->dirty_min = 0;
|
|
vb->dirty_max = VMAP_BBMAP_BITS;
|
|
spin_lock(&vbq->lock);
|
|
list_del_rcu(&vb->free_list);
|
|
spin_unlock(&vbq->lock);
|
|
list_add_tail(&vb->purge, purge_list);
|
|
return true;
|
|
}
|
|
|
|
static void free_purged_blocks(struct list_head *purge_list)
|
|
{
|
|
struct vmap_block *vb, *n_vb;
|
|
|
|
list_for_each_entry_safe(vb, n_vb, purge_list, purge) {
|
|
list_del(&vb->purge);
|
|
free_vmap_block(vb);
|
|
}
|
|
}
|
|
|
|
static void purge_fragmented_blocks(int cpu)
|
|
{
|
|
LIST_HEAD(purge);
|
|
struct vmap_block *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) {
|
|
unsigned long free = READ_ONCE(vb->free);
|
|
unsigned long dirty = READ_ONCE(vb->dirty);
|
|
|
|
if (free + dirty != VMAP_BBMAP_BITS ||
|
|
dirty == VMAP_BBMAP_BITS)
|
|
continue;
|
|
|
|
spin_lock(&vb->lock);
|
|
purge_fragmented_block(vb, vbq, &purge, true);
|
|
spin_unlock(&vb->lock);
|
|
}
|
|
rcu_read_unlock();
|
|
free_purged_blocks(&purge);
|
|
}
|
|
|
|
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 = raw_cpu_ptr(&vmap_block_queue);
|
|
list_for_each_entry_rcu(vb, &vbq->free, free_list) {
|
|
unsigned long pages_off;
|
|
|
|
if (READ_ONCE(vb->free) < (1UL << order))
|
|
continue;
|
|
|
|
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);
|
|
WRITE_ONCE(vb->free, vb->free - (1UL << order));
|
|
bitmap_set(vb->used_map, pages_off, (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;
|
|
}
|
|
|
|
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;
|
|
struct xarray *xa;
|
|
|
|
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;
|
|
|
|
xa = addr_to_vb_xa(addr);
|
|
vb = xa_load(xa, addr_to_vb_idx(addr));
|
|
|
|
spin_lock(&vb->lock);
|
|
bitmap_clear(vb->used_map, offset, (1UL << order));
|
|
spin_unlock(&vb->lock);
|
|
|
|
vunmap_range_noflush(addr, addr + size);
|
|
|
|
if (debug_pagealloc_enabled_static())
|
|
flush_tlb_kernel_range(addr, addr + size);
|
|
|
|
spin_lock(&vb->lock);
|
|
|
|
/* Expand the not yet TLB flushed dirty range */
|
|
vb->dirty_min = min(vb->dirty_min, offset);
|
|
vb->dirty_max = max(vb->dirty_max, offset + (1UL << order));
|
|
|
|
WRITE_ONCE(vb->dirty, 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)
|
|
{
|
|
LIST_HEAD(purge_list);
|
|
int cpu;
|
|
|
|
if (unlikely(!vmap_initialized))
|
|
return;
|
|
|
|
mutex_lock(&vmap_purge_lock);
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
|
|
struct vmap_block *vb;
|
|
unsigned long idx;
|
|
|
|
rcu_read_lock();
|
|
xa_for_each(&vbq->vmap_blocks, idx, vb) {
|
|
spin_lock(&vb->lock);
|
|
|
|
/*
|
|
* Try to purge a fragmented block first. If it's
|
|
* not purgeable, check whether there is dirty
|
|
* space to be flushed.
|
|
*/
|
|
if (!purge_fragmented_block(vb, vbq, &purge_list, false) &&
|
|
vb->dirty_max && vb->dirty != VMAP_BBMAP_BITS) {
|
|
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);
|
|
|
|
/* Prevent that this is flushed again */
|
|
vb->dirty_min = VMAP_BBMAP_BITS;
|
|
vb->dirty_max = 0;
|
|
|
|
flush = 1;
|
|
}
|
|
spin_unlock(&vb->lock);
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
free_purged_blocks(&purge_list);
|
|
|
|
if (!__purge_vmap_area_lazy(start, end, false) && 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)kasan_reset_tag(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_unlink_vmap_area(addr);
|
|
if (WARN_ON_ONCE(!va))
|
|
return;
|
|
|
|
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, VMAP_RAM);
|
|
if (IS_ERR(va))
|
|
return NULL;
|
|
|
|
addr = va->va_start;
|
|
mem = (void *)addr;
|
|
}
|
|
|
|
if (vmap_pages_range(addr, addr + size, PAGE_KERNEL,
|
|
pages, PAGE_SHIFT) < 0) {
|
|
vm_unmap_ram(mem, count);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Mark the pages as accessible, now that they are mapped.
|
|
* With hardware tag-based KASAN, marking is skipped for
|
|
* non-VM_ALLOC mappings, see __kasan_unpoison_vmalloc().
|
|
*/
|
|
mem = kasan_unpoison_vmalloc(mem, size, KASAN_VMALLOC_PROT_NORMAL);
|
|
|
|
return mem;
|
|
}
|
|
EXPORT_SYMBOL(vm_map_ram);
|
|
|
|
static struct vm_struct *vmlist __initdata;
|
|
|
|
static inline unsigned int vm_area_page_order(struct vm_struct *vm)
|
|
{
|
|
#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
|
|
return vm->page_order;
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
static inline void set_vm_area_page_order(struct vm_struct *vm, unsigned int order)
|
|
{
|
|
#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
|
|
vm->page_order = order;
|
|
#else
|
|
BUG_ON(order != 0);
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* 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)
|
|
{
|
|
unsigned long addr = ALIGN(VMALLOC_START, align);
|
|
struct vm_struct *cur, **p;
|
|
|
|
BUG_ON(vmap_initialized);
|
|
|
|
for (p = &vmlist; (cur = *p) != NULL; p = &cur->next) {
|
|
if ((unsigned long)cur->addr - addr >= vm->size)
|
|
break;
|
|
addr = ALIGN((unsigned long)cur->addr + cur->size, align);
|
|
}
|
|
|
|
BUG_ON(addr > VMALLOC_END - vm->size);
|
|
vm->addr = (void *)addr;
|
|
vm->next = *p;
|
|
*p = vm;
|
|
kasan_populate_early_vm_area_shadow(vm->addr, vm->size);
|
|
}
|
|
|
|
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)
|
|
{
|
|
struct vmap_node *vn = addr_to_node(va->va_start);
|
|
|
|
spin_lock(&vn->busy.lock);
|
|
setup_vmalloc_vm_locked(vm, va, flags, caller);
|
|
spin_unlock(&vn->busy.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 shift, 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 = ALIGN(size, 1ul << shift);
|
|
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, 0);
|
|
if (IS_ERR(va)) {
|
|
kfree(area);
|
|
return NULL;
|
|
}
|
|
|
|
setup_vmalloc_vm(area, va, flags, caller);
|
|
|
|
/*
|
|
* Mark pages for non-VM_ALLOC mappings as accessible. Do it now as a
|
|
* best-effort approach, as they can be mapped outside of vmalloc code.
|
|
* For VM_ALLOC mappings, the pages are marked as accessible after
|
|
* getting mapped in __vmalloc_node_range().
|
|
* With hardware tag-based KASAN, marking is skipped for
|
|
* non-VM_ALLOC mappings, see __kasan_unpoison_vmalloc().
|
|
*/
|
|
if (!(flags & VM_ALLOC))
|
|
area->addr = kasan_unpoison_vmalloc(area->addr, requested_size,
|
|
KASAN_VMALLOC_PROT_NORMAL);
|
|
|
|
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, PAGE_SHIFT, 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, PAGE_SHIFT, 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, PAGE_SHIFT, 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;
|
|
struct vm_struct *vm;
|
|
|
|
might_sleep();
|
|
|
|
if (WARN(!PAGE_ALIGNED(addr), "Trying to vfree() bad address (%p)\n",
|
|
addr))
|
|
return NULL;
|
|
|
|
va = find_unlink_vmap_area((unsigned long)addr);
|
|
if (!va || !va->vm)
|
|
return NULL;
|
|
vm = va->vm;
|
|
|
|
debug_check_no_locks_freed(vm->addr, get_vm_area_size(vm));
|
|
debug_check_no_obj_freed(vm->addr, get_vm_area_size(vm));
|
|
kasan_free_module_shadow(vm);
|
|
kasan_poison_vmalloc(vm->addr, get_vm_area_size(vm));
|
|
|
|
free_unmap_vmap_area(va);
|
|
return vm;
|
|
}
|
|
|
|
static inline void set_area_direct_map(const struct vm_struct *area,
|
|
int (*set_direct_map)(struct page *page))
|
|
{
|
|
int i;
|
|
|
|
/* HUGE_VMALLOC passes small pages to set_direct_map */
|
|
for (i = 0; i < area->nr_pages; i++)
|
|
if (page_address(area->pages[i]))
|
|
set_direct_map(area->pages[i]);
|
|
}
|
|
|
|
/*
|
|
* Flush the vm mapping and reset the direct map.
|
|
*/
|
|
static void vm_reset_perms(struct vm_struct *area)
|
|
{
|
|
unsigned long start = ULONG_MAX, end = 0;
|
|
unsigned int page_order = vm_area_page_order(area);
|
|
int flush_dmap = 0;
|
|
int i;
|
|
|
|
/*
|
|
* Find the start and end range of the direct mappings to make sure that
|
|
* the vm_unmap_aliases() flush includes the direct map.
|
|
*/
|
|
for (i = 0; i < area->nr_pages; i += 1U << page_order) {
|
|
unsigned long addr = (unsigned long)page_address(area->pages[i]);
|
|
|
|
if (addr) {
|
|
unsigned long page_size;
|
|
|
|
page_size = PAGE_SIZE << page_order;
|
|
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 delayed_vfree_work(struct work_struct *w)
|
|
{
|
|
struct vfree_deferred *p = container_of(w, struct vfree_deferred, wq);
|
|
struct llist_node *t, *llnode;
|
|
|
|
llist_for_each_safe(llnode, t, llist_del_all(&p->list))
|
|
vfree(llnode);
|
|
}
|
|
|
|
/**
|
|
* 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)
|
|
{
|
|
struct vfree_deferred *p = raw_cpu_ptr(&vfree_deferred);
|
|
|
|
BUG_ON(in_nmi());
|
|
kmemleak_free(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.
|
|
*/
|
|
if (addr && llist_add((struct llist_node *)addr, &p->list))
|
|
schedule_work(&p->wq);
|
|
}
|
|
|
|
/**
|
|
* 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-dependent would be a really bad idea).
|
|
*/
|
|
void vfree(const void *addr)
|
|
{
|
|
struct vm_struct *vm;
|
|
int i;
|
|
|
|
if (unlikely(in_interrupt())) {
|
|
vfree_atomic(addr);
|
|
return;
|
|
}
|
|
|
|
BUG_ON(in_nmi());
|
|
kmemleak_free(addr);
|
|
might_sleep();
|
|
|
|
if (!addr)
|
|
return;
|
|
|
|
vm = remove_vm_area(addr);
|
|
if (unlikely(!vm)) {
|
|
WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n",
|
|
addr);
|
|
return;
|
|
}
|
|
|
|
if (unlikely(vm->flags & VM_FLUSH_RESET_PERMS))
|
|
vm_reset_perms(vm);
|
|
for (i = 0; i < vm->nr_pages; i++) {
|
|
struct page *page = vm->pages[i];
|
|
|
|
BUG_ON(!page);
|
|
mod_memcg_page_state(page, MEMCG_VMALLOC, -1);
|
|
/*
|
|
* High-order allocs for huge vmallocs are split, so
|
|
* can be freed as an array of order-0 allocations
|
|
*/
|
|
__free_page(page);
|
|
cond_resched();
|
|
}
|
|
atomic_long_sub(vm->nr_pages, &nr_vmalloc_pages);
|
|
kvfree(vm->pages);
|
|
kfree(vm);
|
|
}
|
|
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)
|
|
{
|
|
struct vm_struct *vm;
|
|
|
|
BUG_ON(in_interrupt());
|
|
might_sleep();
|
|
|
|
if (!addr)
|
|
return;
|
|
vm = remove_vm_area(addr);
|
|
if (unlikely(!vm)) {
|
|
WARN(1, KERN_ERR "Trying to vunmap() nonexistent vm area (%p)\n",
|
|
addr);
|
|
return;
|
|
}
|
|
kfree(vm);
|
|
}
|
|
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 addr;
|
|
unsigned long size; /* In bytes */
|
|
|
|
might_sleep();
|
|
|
|
if (WARN_ON_ONCE(flags & VM_FLUSH_RESET_PERMS))
|
|
return NULL;
|
|
|
|
/*
|
|
* Your top guard is someone else's bottom guard. Not having a top
|
|
* guard compromises someone else's mappings too.
|
|
*/
|
|
if (WARN_ON_ONCE(flags & VM_NO_GUARD))
|
|
flags &= ~VM_NO_GUARD;
|
|
|
|
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;
|
|
|
|
addr = (unsigned long)area->addr;
|
|
if (vmap_pages_range(addr, addr + size, pgprot_nx(prot),
|
|
pages, PAGE_SHIFT) < 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;
|
|
unsigned long pfn = data->pfns[data->idx];
|
|
pte_t ptent;
|
|
|
|
if (WARN_ON_ONCE(pfn_valid(pfn)))
|
|
return -EINVAL;
|
|
|
|
ptent = pte_mkspecial(pfn_pte(pfn, data->prot));
|
|
set_pte_at(&init_mm, addr, pte, ptent);
|
|
|
|
data->idx++;
|
|
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;
|
|
}
|
|
|
|
flush_cache_vmap((unsigned long)area->addr,
|
|
(unsigned long)area->addr + count * PAGE_SIZE);
|
|
|
|
return area->addr;
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmap_pfn);
|
|
#endif /* CONFIG_VMAP_PFN */
|
|
|
|
static inline unsigned int
|
|
vm_area_alloc_pages(gfp_t gfp, int nid,
|
|
unsigned int order, unsigned int nr_pages, struct page **pages)
|
|
{
|
|
unsigned int nr_allocated = 0;
|
|
gfp_t alloc_gfp = gfp;
|
|
bool nofail = false;
|
|
struct page *page;
|
|
int i;
|
|
|
|
/*
|
|
* For order-0 pages we make use of bulk allocator, if
|
|
* the page array is partly or not at all populated due
|
|
* to fails, fallback to a single page allocator that is
|
|
* more permissive.
|
|
*/
|
|
if (!order) {
|
|
/* bulk allocator doesn't support nofail req. officially */
|
|
gfp_t bulk_gfp = gfp & ~__GFP_NOFAIL;
|
|
|
|
while (nr_allocated < nr_pages) {
|
|
unsigned int nr, nr_pages_request;
|
|
|
|
/*
|
|
* A maximum allowed request is hard-coded and is 100
|
|
* pages per call. That is done in order to prevent a
|
|
* long preemption off scenario in the bulk-allocator
|
|
* so the range is [1:100].
|
|
*/
|
|
nr_pages_request = min(100U, nr_pages - nr_allocated);
|
|
|
|
/* memory allocation should consider mempolicy, we can't
|
|
* wrongly use nearest node when nid == NUMA_NO_NODE,
|
|
* otherwise memory may be allocated in only one node,
|
|
* but mempolicy wants to alloc memory by interleaving.
|
|
*/
|
|
if (IS_ENABLED(CONFIG_NUMA) && nid == NUMA_NO_NODE)
|
|
nr = alloc_pages_bulk_array_mempolicy(bulk_gfp,
|
|
nr_pages_request,
|
|
pages + nr_allocated);
|
|
|
|
else
|
|
nr = alloc_pages_bulk_array_node(bulk_gfp, nid,
|
|
nr_pages_request,
|
|
pages + nr_allocated);
|
|
|
|
nr_allocated += nr;
|
|
cond_resched();
|
|
|
|
/*
|
|
* If zero or pages were obtained partly,
|
|
* fallback to a single page allocator.
|
|
*/
|
|
if (nr != nr_pages_request)
|
|
break;
|
|
}
|
|
} else if (gfp & __GFP_NOFAIL) {
|
|
/*
|
|
* Higher order nofail allocations are really expensive and
|
|
* potentially dangerous (pre-mature OOM, disruptive reclaim
|
|
* and compaction etc.
|
|
*/
|
|
alloc_gfp &= ~__GFP_NOFAIL;
|
|
nofail = true;
|
|
}
|
|
|
|
/* High-order pages or fallback path if "bulk" fails. */
|
|
while (nr_allocated < nr_pages) {
|
|
if (fatal_signal_pending(current))
|
|
break;
|
|
|
|
if (nid == NUMA_NO_NODE)
|
|
page = alloc_pages(alloc_gfp, order);
|
|
else
|
|
page = alloc_pages_node(nid, alloc_gfp, order);
|
|
if (unlikely(!page)) {
|
|
if (!nofail)
|
|
break;
|
|
|
|
/* fall back to the zero order allocations */
|
|
alloc_gfp |= __GFP_NOFAIL;
|
|
order = 0;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Higher order allocations must be able to be treated as
|
|
* indepdenent small pages by callers (as they can with
|
|
* small-page vmallocs). Some drivers do their own refcounting
|
|
* on vmalloc_to_page() pages, some use page->mapping,
|
|
* page->lru, etc.
|
|
*/
|
|
if (order)
|
|
split_page(page, order);
|
|
|
|
/*
|
|
* Careful, we allocate and map page-order pages, but
|
|
* tracking is done per PAGE_SIZE page so as to keep the
|
|
* vm_struct APIs independent of the physical/mapped size.
|
|
*/
|
|
for (i = 0; i < (1U << order); i++)
|
|
pages[nr_allocated + i] = page + i;
|
|
|
|
cond_resched();
|
|
nr_allocated += 1U << order;
|
|
}
|
|
|
|
return nr_allocated;
|
|
}
|
|
|
|
static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
|
|
pgprot_t prot, unsigned int page_shift,
|
|
int node)
|
|
{
|
|
const gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO;
|
|
bool nofail = gfp_mask & __GFP_NOFAIL;
|
|
unsigned long addr = (unsigned long)area->addr;
|
|
unsigned long size = get_vm_area_size(area);
|
|
unsigned long array_size;
|
|
unsigned int nr_small_pages = size >> PAGE_SHIFT;
|
|
unsigned int page_order;
|
|
unsigned int flags;
|
|
int ret;
|
|
|
|
array_size = (unsigned long)nr_small_pages * sizeof(struct page *);
|
|
|
|
if (!(gfp_mask & (GFP_DMA | GFP_DMA32)))
|
|
gfp_mask |= __GFP_HIGHMEM;
|
|
|
|
/* Please note that the recursion is strictly bounded. */
|
|
if (array_size > PAGE_SIZE) {
|
|
area->pages = __vmalloc_node(array_size, 1, nested_gfp, node,
|
|
area->caller);
|
|
} else {
|
|
area->pages = kmalloc_node(array_size, nested_gfp, node);
|
|
}
|
|
|
|
if (!area->pages) {
|
|
warn_alloc(gfp_mask, NULL,
|
|
"vmalloc error: size %lu, failed to allocated page array size %lu",
|
|
nr_small_pages * PAGE_SIZE, array_size);
|
|
free_vm_area(area);
|
|
return NULL;
|
|
}
|
|
|
|
set_vm_area_page_order(area, page_shift - PAGE_SHIFT);
|
|
page_order = vm_area_page_order(area);
|
|
|
|
area->nr_pages = vm_area_alloc_pages(gfp_mask | __GFP_NOWARN,
|
|
node, page_order, nr_small_pages, area->pages);
|
|
|
|
atomic_long_add(area->nr_pages, &nr_vmalloc_pages);
|
|
if (gfp_mask & __GFP_ACCOUNT) {
|
|
int i;
|
|
|
|
for (i = 0; i < area->nr_pages; i++)
|
|
mod_memcg_page_state(area->pages[i], MEMCG_VMALLOC, 1);
|
|
}
|
|
|
|
/*
|
|
* If not enough pages were obtained to accomplish an
|
|
* allocation request, free them via vfree() if any.
|
|
*/
|
|
if (area->nr_pages != nr_small_pages) {
|
|
/*
|
|
* vm_area_alloc_pages() can fail due to insufficient memory but
|
|
* also:-
|
|
*
|
|
* - a pending fatal signal
|
|
* - insufficient huge page-order pages
|
|
*
|
|
* Since we always retry allocations at order-0 in the huge page
|
|
* case a warning for either is spurious.
|
|
*/
|
|
if (!fatal_signal_pending(current) && page_order == 0)
|
|
warn_alloc(gfp_mask, NULL,
|
|
"vmalloc error: size %lu, failed to allocate pages",
|
|
area->nr_pages * PAGE_SIZE);
|
|
goto fail;
|
|
}
|
|
|
|
/*
|
|
* page tables allocations ignore external gfp mask, enforce it
|
|
* by the scope API
|
|
*/
|
|
if ((gfp_mask & (__GFP_FS | __GFP_IO)) == __GFP_IO)
|
|
flags = memalloc_nofs_save();
|
|
else if ((gfp_mask & (__GFP_FS | __GFP_IO)) == 0)
|
|
flags = memalloc_noio_save();
|
|
|
|
do {
|
|
ret = vmap_pages_range(addr, addr + size, prot, area->pages,
|
|
page_shift);
|
|
if (nofail && (ret < 0))
|
|
schedule_timeout_uninterruptible(1);
|
|
} while (nofail && (ret < 0));
|
|
|
|
if ((gfp_mask & (__GFP_FS | __GFP_IO)) == __GFP_IO)
|
|
memalloc_nofs_restore(flags);
|
|
else if ((gfp_mask & (__GFP_FS | __GFP_IO)) == 0)
|
|
memalloc_noio_restore(flags);
|
|
|
|
if (ret < 0) {
|
|
warn_alloc(gfp_mask, NULL,
|
|
"vmalloc error: size %lu, failed to map pages",
|
|
area->nr_pages * PAGE_SIZE);
|
|
goto fail;
|
|
}
|
|
|
|
return area->addr;
|
|
|
|
fail:
|
|
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. Please note that the full set of gfp
|
|
* flags are not supported. GFP_KERNEL, GFP_NOFS and GFP_NOIO are all
|
|
* supported.
|
|
* Zone modifiers are not supported. From the reclaim modifiers
|
|
* __GFP_DIRECT_RECLAIM is required (aka GFP_NOWAIT is not supported)
|
|
* and only __GFP_NOFAIL is supported (i.e. __GFP_NORETRY and
|
|
* __GFP_RETRY_MAYFAIL are not supported).
|
|
*
|
|
* __GFP_NOWARN can be used to suppress failures messages.
|
|
*
|
|
* 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 *ret;
|
|
kasan_vmalloc_flags_t kasan_flags = KASAN_VMALLOC_NONE;
|
|
unsigned long real_size = size;
|
|
unsigned long real_align = align;
|
|
unsigned int shift = PAGE_SHIFT;
|
|
|
|
if (WARN_ON_ONCE(!size))
|
|
return NULL;
|
|
|
|
if ((size >> PAGE_SHIFT) > totalram_pages()) {
|
|
warn_alloc(gfp_mask, NULL,
|
|
"vmalloc error: size %lu, exceeds total pages",
|
|
real_size);
|
|
return NULL;
|
|
}
|
|
|
|
if (vmap_allow_huge && (vm_flags & VM_ALLOW_HUGE_VMAP)) {
|
|
unsigned long size_per_node;
|
|
|
|
/*
|
|
* Try huge pages. Only try for PAGE_KERNEL allocations,
|
|
* others like modules don't yet expect huge pages in
|
|
* their allocations due to apply_to_page_range not
|
|
* supporting them.
|
|
*/
|
|
|
|
size_per_node = size;
|
|
if (node == NUMA_NO_NODE)
|
|
size_per_node /= num_online_nodes();
|
|
if (arch_vmap_pmd_supported(prot) && size_per_node >= PMD_SIZE)
|
|
shift = PMD_SHIFT;
|
|
else
|
|
shift = arch_vmap_pte_supported_shift(size_per_node);
|
|
|
|
align = max(real_align, 1UL << shift);
|
|
size = ALIGN(real_size, 1UL << shift);
|
|
}
|
|
|
|
again:
|
|
area = __get_vm_area_node(real_size, align, shift, VM_ALLOC |
|
|
VM_UNINITIALIZED | vm_flags, start, end, node,
|
|
gfp_mask, caller);
|
|
if (!area) {
|
|
bool nofail = gfp_mask & __GFP_NOFAIL;
|
|
warn_alloc(gfp_mask, NULL,
|
|
"vmalloc error: size %lu, vm_struct allocation failed%s",
|
|
real_size, (nofail) ? ". Retrying." : "");
|
|
if (nofail) {
|
|
schedule_timeout_uninterruptible(1);
|
|
goto again;
|
|
}
|
|
goto fail;
|
|
}
|
|
|
|
/*
|
|
* Prepare arguments for __vmalloc_area_node() and
|
|
* kasan_unpoison_vmalloc().
|
|
*/
|
|
if (pgprot_val(prot) == pgprot_val(PAGE_KERNEL)) {
|
|
if (kasan_hw_tags_enabled()) {
|
|
/*
|
|
* Modify protection bits to allow tagging.
|
|
* This must be done before mapping.
|
|
*/
|
|
prot = arch_vmap_pgprot_tagged(prot);
|
|
|
|
/*
|
|
* Skip page_alloc poisoning and zeroing for physical
|
|
* pages backing VM_ALLOC mapping. Memory is instead
|
|
* poisoned and zeroed by kasan_unpoison_vmalloc().
|
|
*/
|
|
gfp_mask |= __GFP_SKIP_KASAN | __GFP_SKIP_ZERO;
|
|
}
|
|
|
|
/* Take note that the mapping is PAGE_KERNEL. */
|
|
kasan_flags |= KASAN_VMALLOC_PROT_NORMAL;
|
|
}
|
|
|
|
/* Allocate physical pages and map them into vmalloc space. */
|
|
ret = __vmalloc_area_node(area, gfp_mask, prot, shift, node);
|
|
if (!ret)
|
|
goto fail;
|
|
|
|
/*
|
|
* Mark the pages as accessible, now that they are mapped.
|
|
* The condition for setting KASAN_VMALLOC_INIT should complement the
|
|
* one in post_alloc_hook() with regards to the __GFP_SKIP_ZERO check
|
|
* to make sure that memory is initialized under the same conditions.
|
|
* Tag-based KASAN modes only assign tags to normal non-executable
|
|
* allocations, see __kasan_unpoison_vmalloc().
|
|
*/
|
|
kasan_flags |= KASAN_VMALLOC_VM_ALLOC;
|
|
if (!want_init_on_free() && want_init_on_alloc(gfp_mask) &&
|
|
(gfp_mask & __GFP_SKIP_ZERO))
|
|
kasan_flags |= KASAN_VMALLOC_INIT;
|
|
/* KASAN_VMALLOC_PROT_NORMAL already set if required. */
|
|
area->addr = kasan_unpoison_vmalloc(area->addr, real_size, kasan_flags);
|
|
|
|
/*
|
|
* 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);
|
|
|
|
size = PAGE_ALIGN(size);
|
|
if (!(vm_flags & VM_DEFER_KMEMLEAK))
|
|
kmemleak_vmalloc(area, size, gfp_mask);
|
|
|
|
return area->addr;
|
|
|
|
fail:
|
|
if (shift > PAGE_SHIFT) {
|
|
shift = PAGE_SHIFT;
|
|
align = real_align;
|
|
size = real_size;
|
|
goto again;
|
|
}
|
|
|
|
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);
|
|
|
|
/**
|
|
* vmalloc_huge - allocate virtually contiguous memory, allow huge pages
|
|
* @size: allocation size
|
|
* @gfp_mask: flags for the page level allocator
|
|
*
|
|
* Allocate enough pages to cover @size from the page level
|
|
* allocator and map them into contiguous kernel virtual space.
|
|
* If @size is greater than or equal to PMD_SIZE, allow using
|
|
* huge pages for the memory
|
|
*
|
|
* Return: pointer to the allocated memory or %NULL on error
|
|
*/
|
|
void *vmalloc_huge(unsigned long size, gfp_t gfp_mask)
|
|
{
|
|
return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
|
|
gfp_mask, PAGE_KERNEL, VM_ALLOW_HUGE_VMAP,
|
|
NUMA_NO_NODE, __builtin_return_address(0));
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmalloc_huge);
|
|
|
|
/**
|
|
* 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);
|
|
|
|
/*
|
|
* Atomically zero bytes in the iterator.
|
|
*
|
|
* Returns the number of zeroed bytes.
|
|
*/
|
|
static size_t zero_iter(struct iov_iter *iter, size_t count)
|
|
{
|
|
size_t remains = count;
|
|
|
|
while (remains > 0) {
|
|
size_t num, copied;
|
|
|
|
num = min_t(size_t, remains, PAGE_SIZE);
|
|
copied = copy_page_to_iter_nofault(ZERO_PAGE(0), 0, num, iter);
|
|
remains -= copied;
|
|
|
|
if (copied < num)
|
|
break;
|
|
}
|
|
|
|
return count - remains;
|
|
}
|
|
|
|
/*
|
|
* small helper routine, copy contents to iter from addr.
|
|
* If the page is not present, fill zero.
|
|
*
|
|
* Returns the number of copied bytes.
|
|
*/
|
|
static size_t aligned_vread_iter(struct iov_iter *iter,
|
|
const char *addr, size_t count)
|
|
{
|
|
size_t remains = count;
|
|
struct page *page;
|
|
|
|
while (remains > 0) {
|
|
unsigned long offset, length;
|
|
size_t copied = 0;
|
|
|
|
offset = offset_in_page(addr);
|
|
length = PAGE_SIZE - offset;
|
|
if (length > remains)
|
|
length = remains;
|
|
page = 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() calls for this _debug_ interface, rarely
|
|
* used. Instead of that, we'll use an local mapping via
|
|
* copy_page_to_iter_nofault() and accept a small overhead in
|
|
* this access function.
|
|
*/
|
|
if (page)
|
|
copied = copy_page_to_iter_nofault(page, offset,
|
|
length, iter);
|
|
else
|
|
copied = zero_iter(iter, length);
|
|
|
|
addr += copied;
|
|
remains -= copied;
|
|
|
|
if (copied != length)
|
|
break;
|
|
}
|
|
|
|
return count - remains;
|
|
}
|
|
|
|
/*
|
|
* Read from a vm_map_ram region of memory.
|
|
*
|
|
* Returns the number of copied bytes.
|
|
*/
|
|
static size_t vmap_ram_vread_iter(struct iov_iter *iter, const char *addr,
|
|
size_t count, unsigned long flags)
|
|
{
|
|
char *start;
|
|
struct vmap_block *vb;
|
|
struct xarray *xa;
|
|
unsigned long offset;
|
|
unsigned int rs, re;
|
|
size_t remains, n;
|
|
|
|
/*
|
|
* If it's area created by vm_map_ram() interface directly, but
|
|
* not further subdividing and delegating management to vmap_block,
|
|
* handle it here.
|
|
*/
|
|
if (!(flags & VMAP_BLOCK))
|
|
return aligned_vread_iter(iter, addr, count);
|
|
|
|
remains = count;
|
|
|
|
/*
|
|
* Area is split into regions and tracked with vmap_block, read out
|
|
* each region and zero fill the hole between regions.
|
|
*/
|
|
xa = addr_to_vb_xa((unsigned long) addr);
|
|
vb = xa_load(xa, addr_to_vb_idx((unsigned long)addr));
|
|
if (!vb)
|
|
goto finished_zero;
|
|
|
|
spin_lock(&vb->lock);
|
|
if (bitmap_empty(vb->used_map, VMAP_BBMAP_BITS)) {
|
|
spin_unlock(&vb->lock);
|
|
goto finished_zero;
|
|
}
|
|
|
|
for_each_set_bitrange(rs, re, vb->used_map, VMAP_BBMAP_BITS) {
|
|
size_t copied;
|
|
|
|
if (remains == 0)
|
|
goto finished;
|
|
|
|
start = vmap_block_vaddr(vb->va->va_start, rs);
|
|
|
|
if (addr < start) {
|
|
size_t to_zero = min_t(size_t, start - addr, remains);
|
|
size_t zeroed = zero_iter(iter, to_zero);
|
|
|
|
addr += zeroed;
|
|
remains -= zeroed;
|
|
|
|
if (remains == 0 || zeroed != to_zero)
|
|
goto finished;
|
|
}
|
|
|
|
/*it could start reading from the middle of used region*/
|
|
offset = offset_in_page(addr);
|
|
n = ((re - rs + 1) << PAGE_SHIFT) - offset;
|
|
if (n > remains)
|
|
n = remains;
|
|
|
|
copied = aligned_vread_iter(iter, start + offset, n);
|
|
|
|
addr += copied;
|
|
remains -= copied;
|
|
|
|
if (copied != n)
|
|
goto finished;
|
|
}
|
|
|
|
spin_unlock(&vb->lock);
|
|
|
|
finished_zero:
|
|
/* zero-fill the left dirty or free regions */
|
|
return count - remains + zero_iter(iter, remains);
|
|
finished:
|
|
/* We couldn't copy/zero everything */
|
|
spin_unlock(&vb->lock);
|
|
return count - remains;
|
|
}
|
|
|
|
/**
|
|
* vread_iter() - read vmalloc area in a safe way to an iterator.
|
|
* @iter: the iterator to which data should be written.
|
|
* @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 /proc/kcore.
|
|
*
|
|
* 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_iter(struct iov_iter *iter, const char *addr, size_t count)
|
|
{
|
|
struct vmap_node *vn;
|
|
struct vmap_area *va;
|
|
struct vm_struct *vm;
|
|
char *vaddr;
|
|
size_t n, size, flags, remains;
|
|
unsigned long next;
|
|
|
|
addr = kasan_reset_tag(addr);
|
|
|
|
/* Don't allow overflow */
|
|
if ((unsigned long) addr + count < count)
|
|
count = -(unsigned long) addr;
|
|
|
|
remains = count;
|
|
|
|
vn = find_vmap_area_exceed_addr_lock((unsigned long) addr, &va);
|
|
if (!vn)
|
|
goto finished_zero;
|
|
|
|
/* no intersects with alive vmap_area */
|
|
if ((unsigned long)addr + remains <= va->va_start)
|
|
goto finished_zero;
|
|
|
|
do {
|
|
size_t copied;
|
|
|
|
if (remains == 0)
|
|
goto finished;
|
|
|
|
vm = va->vm;
|
|
flags = va->flags & VMAP_FLAGS_MASK;
|
|
/*
|
|
* VMAP_BLOCK indicates a sub-type of vm_map_ram area, need
|
|
* be set together with VMAP_RAM.
|
|
*/
|
|
WARN_ON(flags == VMAP_BLOCK);
|
|
|
|
if (!vm && !flags)
|
|
goto next_va;
|
|
|
|
if (vm && (vm->flags & VM_UNINITIALIZED))
|
|
goto next_va;
|
|
|
|
/* Pair with smp_wmb() in clear_vm_uninitialized_flag() */
|
|
smp_rmb();
|
|
|
|
vaddr = (char *) va->va_start;
|
|
size = vm ? get_vm_area_size(vm) : va_size(va);
|
|
|
|
if (addr >= vaddr + size)
|
|
goto next_va;
|
|
|
|
if (addr < vaddr) {
|
|
size_t to_zero = min_t(size_t, vaddr - addr, remains);
|
|
size_t zeroed = zero_iter(iter, to_zero);
|
|
|
|
addr += zeroed;
|
|
remains -= zeroed;
|
|
|
|
if (remains == 0 || zeroed != to_zero)
|
|
goto finished;
|
|
}
|
|
|
|
n = vaddr + size - addr;
|
|
if (n > remains)
|
|
n = remains;
|
|
|
|
if (flags & VMAP_RAM)
|
|
copied = vmap_ram_vread_iter(iter, addr, n, flags);
|
|
else if (!(vm && (vm->flags & (VM_IOREMAP | VM_SPARSE))))
|
|
copied = aligned_vread_iter(iter, addr, n);
|
|
else /* IOREMAP | SPARSE area is treated as memory hole */
|
|
copied = zero_iter(iter, n);
|
|
|
|
addr += copied;
|
|
remains -= copied;
|
|
|
|
if (copied != n)
|
|
goto finished;
|
|
|
|
next_va:
|
|
next = va->va_end;
|
|
spin_unlock(&vn->busy.lock);
|
|
} while ((vn = find_vmap_area_exceed_addr_lock(next, &va)));
|
|
|
|
finished_zero:
|
|
if (vn)
|
|
spin_unlock(&vn->busy.lock);
|
|
|
|
/* zero-fill memory holes */
|
|
return count - remains + zero_iter(iter, remains);
|
|
finished:
|
|
/* Nothing remains, or We couldn't copy/zero everything. */
|
|
if (vn)
|
|
spin_unlock(&vn->busy.lock);
|
|
|
|
return count - remains;
|
|
}
|
|
|
|
/**
|
|
* 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);
|
|
|
|
vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* 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;
|
|
|
|
/* 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;
|
|
|
|
ret = va_clip(&free_vmap_area_root,
|
|
&free_vmap_area_list, va, start, size);
|
|
if (WARN_ON_ONCE(unlikely(ret)))
|
|
/* It is a BUG(), but trigger recovery instead. */
|
|
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;
|
|
}
|
|
|
|
/* insert all vm's */
|
|
for (area = 0; area < nr_vms; area++) {
|
|
struct vmap_node *vn = addr_to_node(vas[area]->va_start);
|
|
|
|
spin_lock(&vn->busy.lock);
|
|
insert_vmap_area(vas[area], &vn->busy.root, &vn->busy.head);
|
|
setup_vmalloc_vm_locked(vms[area], vas[area], VM_ALLOC,
|
|
pcpu_get_vm_areas);
|
|
spin_unlock(&vn->busy.lock);
|
|
}
|
|
|
|
/*
|
|
* Mark allocated areas as accessible. Do it now as a best-effort
|
|
* approach, as they can be mapped outside of vmalloc code.
|
|
* With hardware tag-based KASAN, marking is skipped for
|
|
* non-VM_ALLOC mappings, see __kasan_unpoison_vmalloc().
|
|
*/
|
|
for (area = 0; area < nr_vms; area++)
|
|
vms[area]->addr = kasan_unpoison_vmalloc(vms[area]->addr,
|
|
vms[area]->size, KASAN_VMALLOC_PROT_NORMAL);
|
|
|
|
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) {
|
|
reclaim_and_purge_vmap_areas();
|
|
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 */
|
|
|
|
#ifdef CONFIG_PRINTK
|
|
bool vmalloc_dump_obj(void *object)
|
|
{
|
|
const void *caller;
|
|
struct vm_struct *vm;
|
|
struct vmap_area *va;
|
|
struct vmap_node *vn;
|
|
unsigned long addr;
|
|
unsigned int nr_pages;
|
|
|
|
addr = PAGE_ALIGN((unsigned long) object);
|
|
vn = addr_to_node(addr);
|
|
|
|
if (!spin_trylock(&vn->busy.lock))
|
|
return false;
|
|
|
|
va = __find_vmap_area(addr, &vn->busy.root);
|
|
if (!va || !va->vm) {
|
|
spin_unlock(&vn->busy.lock);
|
|
return false;
|
|
}
|
|
|
|
vm = va->vm;
|
|
addr = (unsigned long) vm->addr;
|
|
caller = vm->caller;
|
|
nr_pages = vm->nr_pages;
|
|
spin_unlock(&vn->busy.lock);
|
|
|
|
pr_cont(" %u-page vmalloc region starting at %#lx allocated at %pS\n",
|
|
nr_pages, addr, caller);
|
|
|
|
return true;
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static void show_numa_info(struct seq_file *m, struct vm_struct *v)
|
|
{
|
|
if (IS_ENABLED(CONFIG_NUMA)) {
|
|
unsigned int nr, *counters = m->private;
|
|
unsigned int step = 1U << vm_area_page_order(v);
|
|
|
|
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 += step)
|
|
counters[page_to_nid(v->pages[nr])] += step;
|
|
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_node *vn;
|
|
struct vmap_area *va;
|
|
int i;
|
|
|
|
for (i = 0; i < nr_vmap_nodes; i++) {
|
|
vn = &vmap_nodes[i];
|
|
|
|
spin_lock(&vn->lazy.lock);
|
|
list_for_each_entry(va, &vn->lazy.head, 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(&vn->lazy.lock);
|
|
}
|
|
}
|
|
|
|
static int vmalloc_info_show(struct seq_file *m, void *p)
|
|
{
|
|
struct vmap_node *vn;
|
|
struct vmap_area *va;
|
|
struct vm_struct *v;
|
|
int i;
|
|
|
|
for (i = 0; i < nr_vmap_nodes; i++) {
|
|
vn = &vmap_nodes[i];
|
|
|
|
spin_lock(&vn->busy.lock);
|
|
list_for_each_entry(va, &vn->busy.head, list) {
|
|
if (!va->vm) {
|
|
if (va->flags & VMAP_RAM)
|
|
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);
|
|
|
|
continue;
|
|
}
|
|
|
|
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_SPARSE)
|
|
seq_puts(m, " sparse");
|
|
|
|
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');
|
|
}
|
|
spin_unlock(&vn->busy.lock);
|
|
}
|
|
|
|
/*
|
|
* As a final step, dump "unpurged" areas.
|
|
*/
|
|
show_purge_info(m);
|
|
return 0;
|
|
}
|
|
|
|
static int __init proc_vmalloc_init(void)
|
|
{
|
|
void *priv_data = NULL;
|
|
|
|
if (IS_ENABLED(CONFIG_NUMA))
|
|
priv_data = kmalloc(nr_node_ids * sizeof(unsigned int), GFP_KERNEL);
|
|
|
|
proc_create_single_data("vmallocinfo",
|
|
0400, NULL, vmalloc_info_show, priv_data);
|
|
|
|
return 0;
|
|
}
|
|
module_init(proc_vmalloc_init);
|
|
|
|
#endif
|
|
|
|
static void __init vmap_init_free_space(void)
|
|
{
|
|
unsigned long vmap_start = 1;
|
|
const unsigned long vmap_end = ULONG_MAX;
|
|
struct vmap_area *free;
|
|
struct vm_struct *busy;
|
|
|
|
/*
|
|
* B F B B B F
|
|
* -|-----|.....|-----|-----|-----|.....|-
|
|
* | The KVA space |
|
|
* |<--------------------------------->|
|
|
*/
|
|
for (busy = vmlist; busy; busy = busy->next) {
|
|
if ((unsigned long) busy->addr - 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 = (unsigned long) busy->addr;
|
|
|
|
insert_vmap_area_augment(free, NULL,
|
|
&free_vmap_area_root,
|
|
&free_vmap_area_list);
|
|
}
|
|
}
|
|
|
|
vmap_start = (unsigned long) busy->addr + busy->size;
|
|
}
|
|
|
|
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);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void vmap_init_nodes(void)
|
|
{
|
|
struct vmap_node *vn;
|
|
int i, n;
|
|
|
|
#if BITS_PER_LONG == 64
|
|
/*
|
|
* A high threshold of max nodes is fixed and bound to 128,
|
|
* thus a scale factor is 1 for systems where number of cores
|
|
* are less or equal to specified threshold.
|
|
*
|
|
* As for NUMA-aware notes. For bigger systems, for example
|
|
* NUMA with multi-sockets, where we can end-up with thousands
|
|
* of cores in total, a "sub-numa-clustering" should be added.
|
|
*
|
|
* In this case a NUMA domain is considered as a single entity
|
|
* with dedicated sub-nodes in it which describe one group or
|
|
* set of cores. Therefore a per-domain purging is supposed to
|
|
* be added as well as a per-domain balancing.
|
|
*/
|
|
n = clamp_t(unsigned int, num_possible_cpus(), 1, 128);
|
|
|
|
if (n > 1) {
|
|
vn = kmalloc_array(n, sizeof(*vn), GFP_NOWAIT | __GFP_NOWARN);
|
|
if (vn) {
|
|
/* Node partition is 16 pages. */
|
|
vmap_zone_size = (1 << 4) * PAGE_SIZE;
|
|
nr_vmap_nodes = n;
|
|
vmap_nodes = vn;
|
|
} else {
|
|
pr_err("Failed to allocate an array. Disable a node layer\n");
|
|
}
|
|
}
|
|
#endif
|
|
|
|
for (n = 0; n < nr_vmap_nodes; n++) {
|
|
vn = &vmap_nodes[n];
|
|
vn->busy.root = RB_ROOT;
|
|
INIT_LIST_HEAD(&vn->busy.head);
|
|
spin_lock_init(&vn->busy.lock);
|
|
|
|
vn->lazy.root = RB_ROOT;
|
|
INIT_LIST_HEAD(&vn->lazy.head);
|
|
spin_lock_init(&vn->lazy.lock);
|
|
|
|
for (i = 0; i < MAX_VA_SIZE_PAGES; i++) {
|
|
INIT_LIST_HEAD(&vn->pool[i].head);
|
|
WRITE_ONCE(vn->pool[i].len, 0);
|
|
}
|
|
|
|
spin_lock_init(&vn->pool_lock);
|
|
}
|
|
}
|
|
|
|
static unsigned long
|
|
vmap_node_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
|
|
{
|
|
unsigned long count;
|
|
struct vmap_node *vn;
|
|
int i, j;
|
|
|
|
for (count = 0, i = 0; i < nr_vmap_nodes; i++) {
|
|
vn = &vmap_nodes[i];
|
|
|
|
for (j = 0; j < MAX_VA_SIZE_PAGES; j++)
|
|
count += READ_ONCE(vn->pool[j].len);
|
|
}
|
|
|
|
return count ? count : SHRINK_EMPTY;
|
|
}
|
|
|
|
static unsigned long
|
|
vmap_node_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < nr_vmap_nodes; i++)
|
|
decay_va_pool_node(&vmap_nodes[i], true);
|
|
|
|
return SHRINK_STOP;
|
|
}
|
|
|
|
void __init vmalloc_init(void)
|
|
{
|
|
struct shrinker *vmap_node_shrinker;
|
|
struct vmap_area *va;
|
|
struct vmap_node *vn;
|
|
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, delayed_vfree_work);
|
|
xa_init(&vbq->vmap_blocks);
|
|
}
|
|
|
|
/*
|
|
* Setup nodes before importing vmlist.
|
|
*/
|
|
vmap_init_nodes();
|
|
|
|
/* 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;
|
|
|
|
vn = addr_to_node(va->va_start);
|
|
insert_vmap_area(va, &vn->busy.root, &vn->busy.head);
|
|
}
|
|
|
|
/*
|
|
* Now we can initialize a free vmap space.
|
|
*/
|
|
vmap_init_free_space();
|
|
vmap_initialized = true;
|
|
|
|
vmap_node_shrinker = shrinker_alloc(0, "vmap-node");
|
|
if (!vmap_node_shrinker) {
|
|
pr_err("Failed to allocate vmap-node shrinker!\n");
|
|
return;
|
|
}
|
|
|
|
vmap_node_shrinker->count_objects = vmap_node_shrink_count;
|
|
vmap_node_shrinker->scan_objects = vmap_node_shrink_scan;
|
|
shrinker_register(vmap_node_shrinker);
|
|
}
|