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mm: replace vma prio_tree with an interval tree

Browse source 
Implement an interval tree as a replacement for the VMA prio_tree.  The
algorithms are similar to lib/interval_tree.c; however that code can't be
directly reused as the interval endpoints are not explicitly stored in the
VMA.  So instead, the common algorithm is moved into a template and the
details (node type, how to get interval endpoints from the node, etc) are
filled in using the C preprocessor.

Once the interval tree functions are available, using them as a
replacement to the VMA prio tree is a relatively simple, mechanical job.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michel Lespinasse 2012-10-08 16:31:25 -07:00 committed by Linus Torvalds
parent fff3fd8a12
commit 6b2dbba8b6
25 changed files with 355 additions and 464 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
arch/arm/mm/fault-armv.c
View file

@ -134,7 +134,6 @@ make_coherent(struct address_space *mapping, struct vm_area_struct *vma,
{
struct mm_struct *mm = vma->vm_mm;
struct vm_area_struct *mpnt;
struct prio_tree_iter iter;
unsigned long offset;
pgoff_t pgoff;
int aliases = 0;
@ -147,7 +146,7 @@ make_coherent(struct address_space *mapping, struct vm_area_struct *vma,
* cache coherency.
*/
flush_dcache_mmap_lock(mapping);
vma_prio_tree_foreach(mpnt, &iter, &mapping->i_mmap, pgoff, pgoff) {
vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
/*
* If this VMA is not in our MM, we can ignore it.
* Note that we intentionally mask out the VMA

3
arch/arm/mm/flush.c
View file

@ -196,7 +196,6 @@ static void __flush_dcache_aliases(struct address_space *mapping, struct page *p
{
struct mm_struct *mm = current->active_mm;
struct vm_area_struct *mpnt;
struct prio_tree_iter iter;
pgoff_t pgoff;
/*
@ -208,7 +207,7 @@ static void __flush_dcache_aliases(struct address_space *mapping, struct page *p
pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
flush_dcache_mmap_lock(mapping);
vma_prio_tree_foreach(mpnt, &iter, &mapping->i_mmap, pgoff, pgoff) {
vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
unsigned long offset;
/*

3
arch/parisc/kernel/cache.c
View file

@ -276,7 +276,6 @@ void flush_dcache_page(struct page *page)
{
struct address_space *mapping = page_mapping(page);
struct vm_area_struct *mpnt;
struct prio_tree_iter iter;
unsigned long offset;
unsigned long addr, old_addr = 0;
pgoff_t pgoff;
@ -299,7 +298,7 @@ void flush_dcache_page(struct page *page)
* to flush one address here for them all to become coherent */
flush_dcache_mmap_lock(mapping);
vma_prio_tree_foreach(mpnt, &iter, &mapping->i_mmap, pgoff, pgoff) {
vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
addr = mpnt->vm_start + offset;

3
arch/x86/mm/hugetlbpage.c
View file

@ -71,7 +71,6 @@ huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
struct address_space *mapping = vma->vm_file->f_mapping;
pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) +
vma->vm_pgoff;
struct prio_tree_iter iter;
struct vm_area_struct *svma;
unsigned long saddr;
pte_t *spte = NULL;
@ -81,7 +80,7 @@ huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
return (pte_t *)pmd_alloc(mm, pud, addr);
mutex_lock(&mapping->i_mmap_mutex);
vma_prio_tree_foreach(svma, &iter, &mapping->i_mmap, idx, idx) {
vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) {
if (svma == vma)
continue;

9
fs/hugetlbfs/inode.c
View file

@ -397,17 +397,16 @@ static void hugetlbfs_evict_inode(struct inode *inode)
}
static inline void
hugetlb_vmtruncate_list(struct prio_tree_root *root, pgoff_t pgoff)
hugetlb_vmtruncate_list(struct rb_root *root, pgoff_t pgoff)
{
struct vm_area_struct *vma;
struct prio_tree_iter iter;
vma_prio_tree_foreach(vma, &iter, root, pgoff, ULONG_MAX) {
vma_interval_tree_foreach(vma, root, pgoff, ULONG_MAX) {
unsigned long v_offset;
/*
* Can the expression below overflow on 32-bit arches?
* No, because the prio_tree returns us only those vmas
* No, because the interval tree returns us only those vmas
* which overlap the truncated area starting at pgoff,
* and no vma on a 32-bit arch can span beyond the 4GB.
*/
@ -432,7 +431,7 @@ static int hugetlb_vmtruncate(struct inode *inode, loff_t offset)
i_size_write(inode, offset);
mutex_lock(&mapping->i_mmap_mutex);
if (!prio_tree_empty(&mapping->i_mmap))
if (!RB_EMPTY_ROOT(&mapping->i_mmap))
hugetlb_vmtruncate_list(&mapping->i_mmap, pgoff);
mutex_unlock(&mapping->i_mmap_mutex);
truncate_hugepages(inode, offset);

2
fs/inode.c
View file

@ -348,7 +348,7 @@ void address_space_init_once(struct address_space *mapping)
mutex_init(&mapping->i_mmap_mutex);
INIT_LIST_HEAD(&mapping->private_list);
spin_lock_init(&mapping->private_lock);
INIT_RAW_PRIO_TREE_ROOT(&mapping->i_mmap);
mapping->i_mmap = RB_ROOT;
INIT_LIST_HEAD(&mapping->i_mmap_nonlinear);
}
EXPORT_SYMBOL(address_space_init_once);

6
include/linux/fs.h
View file

@ -401,7 +401,7 @@ struct inodes_stat_t {
#include <linux/cache.h>
#include <linux/list.h>
#include <linux/radix-tree.h>
#include <linux/prio_tree.h>
#include <linux/rbtree.h>
#include <linux/init.h>
#include <linux/pid.h>
#include <linux/bug.h>
@ -669,7 +669,7 @@ struct address_space {
struct radix_tree_root page_tree; /* radix tree of all pages */
spinlock_t tree_lock; /* and lock protecting it */
unsigned int i_mmap_writable;/* count VM_SHARED mappings */
struct prio_tree_root i_mmap; /* tree of private and shared mappings */
struct rb_root i_mmap; /* tree of private and shared mappings */
struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */
struct mutex i_mmap_mutex; /* protect tree, count, list */
/* Protected by tree_lock together with the radix tree */
@ -741,7 +741,7 @@ int mapping_tagged(struct address_space *mapping, int tag);
*/
static inline int mapping_mapped(struct address_space *mapping)
{
return !prio_tree_empty(&mapping->i_mmap) ||
return !RB_EMPTY_ROOT(&mapping->i_mmap) ||
!list_empty(&mapping->i_mmap_nonlinear);
}

215
include/linux/interval_tree_tmpl.h Normal file
View file

@ -0,0 +1,215 @@
/*
Interval Trees
(C) 2012 Michel Lespinasse <walken@google.com>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
include/linux/interval_tree_tmpl.h
*/
/*
* Template for implementing interval trees
*
* ITSTRUCT: struct type of the interval tree nodes
* ITRB: name of struct rb_node field within ITSTRUCT
* ITTYPE: type of the interval endpoints
* ITSUBTREE: name of ITTYPE field within ITSTRUCT holding last-in-subtree
* ITSTART(n): start endpoint of ITSTRUCT node n
* ITLAST(n): last endpoing of ITSTRUCT node n
* ITSTATIC: 'static' or empty
* ITPREFIX: prefix to use for the inline tree definitions
*/
/* IT(name) -> ITPREFIX_name */
#define _ITNAME(prefix, name) prefix ## _ ## name
#define ITNAME(prefix, name) _ITNAME(prefix, name)
#define IT(name) ITNAME(ITPREFIX, name)
/* Callbacks for augmented rbtree insert and remove */
static inline ITTYPE IT(compute_subtree_last)(ITSTRUCT *node)
{
ITTYPE max = ITLAST(node), subtree_last;
if (node->ITRB.rb_left) {
subtree_last = rb_entry(node->ITRB.rb_left,
ITSTRUCT, ITRB)->ITSUBTREE;
if (max < subtree_last)
max = subtree_last;
}
if (node->ITRB.rb_right) {
subtree_last = rb_entry(node->ITRB.rb_right,
ITSTRUCT, ITRB)->ITSUBTREE;
if (max < subtree_last)
max = subtree_last;
}
return max;
}
static void IT(augment_propagate)(struct rb_node *rb, struct rb_node *stop)
{
while (rb != stop) {
ITSTRUCT *node = rb_entry(rb, ITSTRUCT, ITRB);
ITTYPE subtree_last = IT(compute_subtree_last)(node);
if (node->ITSUBTREE == subtree_last)
break;
node->ITSUBTREE = subtree_last;
rb = rb_parent(&node->ITRB);
}
}
static void IT(augment_copy)(struct rb_node *rb_old, struct rb_node *rb_new)
{
ITSTRUCT *old = rb_entry(rb_old, ITSTRUCT, ITRB);
ITSTRUCT *new = rb_entry(rb_new, ITSTRUCT, ITRB);
new->ITSUBTREE = old->ITSUBTREE;
}
static void IT(augment_rotate)(struct rb_node *rb_old, struct rb_node *rb_new)
{
ITSTRUCT *old = rb_entry(rb_old, ITSTRUCT, ITRB);
ITSTRUCT *new = rb_entry(rb_new, ITSTRUCT, ITRB);
new->ITSUBTREE = old->ITSUBTREE;
old->ITSUBTREE = IT(compute_subtree_last)(old);
}
static const struct rb_augment_callbacks IT(augment_callbacks) = {
IT(augment_propagate), IT(augment_copy), IT(augment_rotate)
};
/* Insert / remove interval nodes from the tree */
ITSTATIC void IT(insert)(ITSTRUCT *node, struct rb_root *root)
{
struct rb_node **link = &root->rb_node, *rb_parent = NULL;
ITTYPE start = ITSTART(node), last = ITLAST(node);
ITSTRUCT *parent;
while (*link) {
rb_parent = *link;
parent = rb_entry(rb_parent, ITSTRUCT, ITRB);
if (parent->ITSUBTREE < last)
parent->ITSUBTREE = last;
if (start < ITSTART(parent))
link = &parent->ITRB.rb_left;
else
link = &parent->ITRB.rb_right;
}
node->ITSUBTREE = last;
rb_link_node(&node->ITRB, rb_parent, link);
rb_insert_augmented(&node->ITRB, root, &IT(augment_callbacks));
}
ITSTATIC void IT(remove)(ITSTRUCT *node, struct rb_root *root)
{
rb_erase_augmented(&node->ITRB, root, &IT(augment_callbacks));
}
/*
* Iterate over intervals intersecting [start;last]
*
* Note that a node's interval intersects [start;last] iff:
* Cond1: ITSTART(node) <= last
* and
* Cond2: start <= ITLAST(node)
*/
static ITSTRUCT *IT(subtree_search)(ITSTRUCT *node, ITTYPE start, ITTYPE last)
{
while (true) {
/*
* Loop invariant: start <= node->ITSUBTREE
* (Cond2 is satisfied by one of the subtree nodes)
*/
if (node->ITRB.rb_left) {
ITSTRUCT *left = rb_entry(node->ITRB.rb_left,
ITSTRUCT, ITRB);
if (start <= left->ITSUBTREE) {
/*
* Some nodes in left subtree satisfy Cond2.
* Iterate to find the leftmost such node N.
* If it also satisfies Cond1, that's the match
* we are looking for. Otherwise, there is no
* matching interval as nodes to the right of N
* can't satisfy Cond1 either.
*/
node = left;
continue;
}
}
if (ITSTART(node) <= last) { /* Cond1 */
if (start <= ITLAST(node)) /* Cond2 */
return node; /* node is leftmost match */
if (node->ITRB.rb_right) {
node = rb_entry(node->ITRB.rb_right,
ITSTRUCT, ITRB);
if (start <= node->ITSUBTREE)
continue;
}
}
return NULL; /* No match */
}
}
ITSTATIC ITSTRUCT *IT(iter_first)(struct rb_root *root,
ITTYPE start, ITTYPE last)
{
ITSTRUCT *node;
if (!root->rb_node)
return NULL;
node = rb_entry(root->rb_node, ITSTRUCT, ITRB);
if (node->ITSUBTREE < start)
return NULL;
return IT(subtree_search)(node, start, last);
}
ITSTATIC ITSTRUCT *IT(iter_next)(ITSTRUCT *node, ITTYPE start, ITTYPE last)
{
struct rb_node *rb = node->ITRB.rb_right, *prev;
while (true) {
/*
* Loop invariants:
* Cond1: ITSTART(node) <= last
* rb == node->ITRB.rb_right
*
* First, search right subtree if suitable
*/
if (rb) {
ITSTRUCT *right = rb_entry(rb, ITSTRUCT, ITRB);
if (start <= right->ITSUBTREE)
return IT(subtree_search)(right, start, last);
}
/* Move up the tree until we come from a node's left child */
do {
rb = rb_parent(&node->ITRB);
if (!rb)
return NULL;
prev = &node->ITRB;
node = rb_entry(rb, ITSTRUCT, ITRB);
rb = node->ITRB.rb_right;
} while (prev == rb);
/* Check if the node intersects [start;last] */
if (last < ITSTART(node)) /* !Cond1 */
return NULL;
else if (start <= ITLAST(node)) /* Cond2 */
return node;
}
}

28
include/linux/mm.h
View file

@ -10,7 +10,6 @@
#include <linux/list.h>
#include <linux/mmzone.h>
#include <linux/rbtree.h>
#include <linux/prio_tree.h>
#include <linux/atomic.h>
#include <linux/debug_locks.h>
#include <linux/mm_types.h>
@ -1355,22 +1354,27 @@ extern void zone_pcp_reset(struct zone *zone);
extern atomic_long_t mmap_pages_allocated;
extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);
/* prio_tree.c */
void vma_prio_tree_add(struct vm_area_struct *, struct vm_area_struct *old);
void vma_prio_tree_insert(struct vm_area_struct *, struct prio_tree_root *);
void vma_prio_tree_remove(struct vm_area_struct *, struct prio_tree_root *);
struct vm_area_struct *vma_prio_tree_next(struct vm_area_struct *vma,
struct prio_tree_iter *iter);
/* interval_tree.c */
void vma_interval_tree_add(struct vm_area_struct *vma,
struct vm_area_struct *old,
struct address_space *mapping);
void vma_interval_tree_insert(struct vm_area_struct *node,
struct rb_root *root);
void vma_interval_tree_remove(struct vm_area_struct *node,
struct rb_root *root);
struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root *root,
unsigned long start, unsigned long last);
struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node,
unsigned long start, unsigned long last);
#define vma_prio_tree_foreach(vma, iter, root, begin, end) \
for (prio_tree_iter_init(iter, root, begin, end), vma = NULL; \
(vma = vma_prio_tree_next(vma, iter)); )
#define vma_interval_tree_foreach(vma, root, start, last) \
for (vma = vma_interval_tree_iter_first(root, start, last); \
vma; vma = vma_interval_tree_iter_next(vma, start, last))
static inline void vma_nonlinear_insert(struct vm_area_struct *vma,
struct list_head *list)
{
vma->shared.vm_set.parent = NULL;
list_add_tail(&vma->shared.vm_set.list, list);
list_add_tail(&vma->shared.nonlinear, list);
}
/* mmap.c */

14
include/linux/mm_types.h
View file

@ -6,7 +6,6 @@
#include <linux/threads.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/prio_tree.h>
#include <linux/rbtree.h>
#include <linux/rwsem.h>
#include <linux/completion.h>
@ -240,18 +239,15 @@ struct vm_area_struct {
/*
* For areas with an address space and backing store,
* linkage into the address_space->i_mmap prio tree, or
* linkage to the list of like vmas hanging off its node, or
* linkage into the address_space->i_mmap interval tree, or
* linkage of vma in the address_space->i_mmap_nonlinear list.
*/
union {
struct {
struct list_head list;
void *parent; /* aligns with prio_tree_node parent */
struct vm_area_struct *head;
} vm_set;
struct raw_prio_tree_node prio_tree_node;
struct rb_node rb;
unsigned long rb_subtree_last;
} linear;
struct list_head nonlinear;
} shared;
/*

3
kernel/events/uprobes.c
View file

@ -735,7 +735,6 @@ static struct map_info *
build_map_info(struct address_space *mapping, loff_t offset, bool is_register)
{
unsigned long pgoff = offset >> PAGE_SHIFT;
struct prio_tree_iter iter;
struct vm_area_struct *vma;
struct map_info *curr = NULL;
struct map_info *prev = NULL;
@ -744,7 +743,7 @@ build_map_info(struct address_space *mapping, loff_t offset, bool is_register)
again:
mutex_lock(&mapping->i_mmap_mutex);
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
if (!valid_vma(vma, is_register))
continue;

2
kernel/fork.c
View file

@ -423,7 +423,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
mapping->i_mmap_writable++;
flush_dcache_mmap_lock(mapping);
/* insert tmp into the share list, just after mpnt */
vma_prio_tree_add(tmp, mpnt);
vma_interval_tree_add(tmp, mpnt, mapping);
flush_dcache_mmap_unlock(mapping);
mutex_unlock(&mapping->i_mmap_mutex);
}

164
lib/interval_tree.c
View file

@ -1,159 +1,13 @@
#include <linux/init.h>
#include <linux/interval_tree.h>
/* Callbacks for augmented rbtree insert and remove */
#define ITSTRUCT struct interval_tree_node
#define ITRB rb
#define ITTYPE unsigned long
#define ITSUBTREE __subtree_last
#define ITSTART(n) ((n)->start)
#define ITLAST(n) ((n)->last)
#define ITSTATIC
#define ITPREFIX interval_tree
static inline unsigned long
compute_subtree_last(struct interval_tree_node *node)
{
unsigned long max = node->last, subtree_last;
if (node->rb.rb_left) {
subtree_last = rb_entry(node->rb.rb_left,
struct interval_tree_node, rb)->__subtree_last;
if (max < subtree_last)
max = subtree_last;
}
if (node->rb.rb_right) {
subtree_last = rb_entry(node->rb.rb_right,
struct interval_tree_node, rb)->__subtree_last;
if (max < subtree_last)
max = subtree_last;
}
return max;
}
RB_DECLARE_CALLBACKS(static, augment_callbacks, struct interval_tree_node, rb,
unsigned long, __subtree_last, compute_subtree_last)
/* Insert / remove interval nodes from the tree */
void interval_tree_insert(struct interval_tree_node *node,
struct rb_root *root)
{
struct rb_node **link = &root->rb_node, *rb_parent = NULL;
unsigned long start = node->start, last = node->last;
struct interval_tree_node *parent;
while (*link) {
rb_parent = *link;
parent = rb_entry(rb_parent, struct interval_tree_node, rb);
if (parent->__subtree_last < last)
parent->__subtree_last = last;
if (start < parent->start)
link = &parent->rb.rb_left;
else
link = &parent->rb.rb_right;
}
node->__subtree_last = last;
rb_link_node(&node->rb, rb_parent, link);
rb_insert_augmented(&node->rb, root, &augment_callbacks);
}
void interval_tree_remove(struct interval_tree_node *node,
struct rb_root *root)
{
rb_erase_augmented(&node->rb, root, &augment_callbacks);
}
/*
* Iterate over intervals intersecting [start;last]
*
* Note that a node's interval intersects [start;last] iff:
* Cond1: node->start <= last
* and
* Cond2: start <= node->last
*/
static struct interval_tree_node *
subtree_search(struct interval_tree_node *node,
unsigned long start, unsigned long last)
{
while (true) {
/*
* Loop invariant: start <= node->__subtree_last
* (Cond2 is satisfied by one of the subtree nodes)
*/
if (node->rb.rb_left) {
struct interval_tree_node *left =
rb_entry(node->rb.rb_left,
struct interval_tree_node, rb);
if (start <= left->__subtree_last) {
/*
* Some nodes in left subtree satisfy Cond2.
* Iterate to find the leftmost such node N.
* If it also satisfies Cond1, that's the match
* we are looking for. Otherwise, there is no
* matching interval as nodes to the right of N
* can't satisfy Cond1 either.
*/
node = left;
continue;
}
}
if (node->start <= last) { /* Cond1 */
if (start <= node->last) /* Cond2 */
return node; /* node is leftmost match */
if (node->rb.rb_right) {
node = rb_entry(node->rb.rb_right,
struct interval_tree_node, rb);
if (start <= node->__subtree_last)
continue;
}
}
return NULL; /* No match */
}
}
struct interval_tree_node *
interval_tree_iter_first(struct rb_root *root,
unsigned long start, unsigned long last)
{
struct interval_tree_node *node;
if (!root->rb_node)
return NULL;
node = rb_entry(root->rb_node, struct interval_tree_node, rb);
if (node->__subtree_last < start)
return NULL;
return subtree_search(node, start, last);
}
struct interval_tree_node *
interval_tree_iter_next(struct interval_tree_node *node,
unsigned long start, unsigned long last)
{
struct rb_node *rb = node->rb.rb_right, *prev;
while (true) {
/*
* Loop invariants:
* Cond1: node->start <= last
* rb == node->rb.rb_right
*
* First, search right subtree if suitable
*/
if (rb) {
struct interval_tree_node *right =
rb_entry(rb, struct interval_tree_node, rb);
if (start <= right->__subtree_last)
return subtree_search(right, start, last);
}
/* Move up the tree until we come from a node's left child */
do {
rb = rb_parent(&node->rb);
if (!rb)
return NULL;
prev = &node->rb;
node = rb_entry(rb, struct interval_tree_node, rb);
rb = node->rb.rb_right;
} while (prev == rb);
/* Check if the node intersects [start;last] */
if (last < node->start) /* !Cond1 */
return NULL;
else if (start <= node->last) /* Cond2 */
return node;
}
}
#include <linux/interval_tree_tmpl.h>

19
lib/prio_tree.c
View file

@ -44,27 +44,12 @@
* The following macros are used for implementing prio_tree for i_mmap
*/
#define RADIX_INDEX(vma) ((vma)->vm_pgoff)
#define VMA_SIZE(vma) (((vma)->vm_end - (vma)->vm_start) >> PAGE_SHIFT)
/* avoid overflow */
#define HEAP_INDEX(vma) ((vma)->vm_pgoff + (VMA_SIZE(vma) - 1))
static void get_index(const struct prio_tree_root *root,
const struct prio_tree_node *node,
unsigned long *radix, unsigned long *heap)
{
if (root->raw) {
struct vm_area_struct *vma = prio_tree_entry(
node, struct vm_area_struct, shared.prio_tree_node);
*radix = RADIX_INDEX(vma);
*heap = HEAP_INDEX(vma);
}
else {
*radix = node->start;
*heap = node->last;
}
*radix = node->start;
*heap = node->last;
}
static unsigned long index_bits_to_maxindex[BITS_PER_LONG];

4
mm/Makefile
View file

@ -14,9 +14,9 @@ endif
obj-y := filemap.o mempool.o oom_kill.o fadvise.o \
maccess.o page_alloc.o page-writeback.o \
readahead.o swap.o truncate.o vmscan.o shmem.o \
prio_tree.o util.o mmzone.o vmstat.o backing-dev.o \
util.o mmzone.o vmstat.o backing-dev.o \
mm_init.o mmu_context.o percpu.o slab_common.o \
compaction.o $(mmu-y)
compaction.o interval_tree.o $(mmu-y)
obj-y += init-mm.o

3
mm/filemap_xip.c
View file

@ -167,7 +167,6 @@ __xip_unmap (struct address_space * mapping,
{
struct vm_area_struct *vma;
struct mm_struct *mm;
struct prio_tree_iter iter;
unsigned long address;
pte_t *pte;
pte_t pteval;
@ -184,7 +183,7 @@ __xip_unmap (struct address_space * mapping,
retry:
mutex_lock(&mapping->i_mmap_mutex);
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
mm = vma->vm_mm;
address = vma->vm_start +
((pgoff - vma->vm_pgoff) << PAGE_SHIFT);

2
mm/fremap.c
View file

@ -214,7 +214,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
mutex_lock(&mapping->i_mmap_mutex);
flush_dcache_mmap_lock(mapping);
vma->vm_flags |= VM_NONLINEAR;
vma_prio_tree_remove(vma, &mapping->i_mmap);
vma_interval_tree_remove(vma, &mapping->i_mmap);
vma_nonlinear_insert(vma, &mapping->i_mmap_nonlinear);
flush_dcache_mmap_unlock(mapping);
mutex_unlock(&mapping->i_mmap_mutex);

3
mm/hugetlb.c
View file

@ -2474,7 +2474,6 @@ static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
struct hstate *h = hstate_vma(vma);
struct vm_area_struct *iter_vma;
struct address_space *mapping;
struct prio_tree_iter iter;
pgoff_t pgoff;
/*
@ -2491,7 +2490,7 @@ static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
* __unmap_hugepage_range() is called as the lock is already held
*/
mutex_lock(&mapping->i_mmap_mutex);
vma_prio_tree_foreach(iter_vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
vma_interval_tree_foreach(iter_vma, &mapping->i_mmap, pgoff, pgoff) {
/* Do not unmap the current VMA */
if (iter_vma == vma)
continue;

61
mm/interval_tree.c Normal file
View file

@ -0,0 +1,61 @@
/*
* mm/interval_tree.c - interval tree for mapping->i_mmap
*
* Copyright (C) 2012, Michel Lespinasse <walken@google.com>
*
* This file is released under the GPL v2.
*/
#include <linux/mm.h>
#include <linux/fs.h>
#define ITSTRUCT struct vm_area_struct
#define ITRB shared.linear.rb
#define ITTYPE unsigned long
#define ITSUBTREE shared.linear.rb_subtree_last
#define ITSTART(n) ((n)->vm_pgoff)
#define ITLAST(n) ((n)->vm_pgoff + \
(((n)->vm_end - (n)->vm_start) >> PAGE_SHIFT) - 1)
#define ITSTATIC
#define ITPREFIX vma_interval_tree
#include <linux/interval_tree_tmpl.h>
/* Insert old immediately after vma in the interval tree */
void vma_interval_tree_add(struct vm_area_struct *vma,
struct vm_area_struct *old,
struct address_space *mapping)
{
struct rb_node **link;
struct vm_area_struct *parent;
unsigned long last;
if (unlikely(vma->vm_flags & VM_NONLINEAR)) {
list_add(&vma->shared.nonlinear, &old->shared.nonlinear);
return;
}
last = ITLAST(vma);
if (!old->shared.linear.rb.rb_right) {
parent = old;
link = &old->shared.linear.rb.rb_right;
} else {
parent = rb_entry(old->shared.linear.rb.rb_right,
struct vm_area_struct, shared.linear.rb);
if (parent->shared.linear.rb_subtree_last < last)
parent->shared.linear.rb_subtree_last = last;
while (parent->shared.linear.rb.rb_left) {
parent = rb_entry(parent->shared.linear.rb.rb_left,
struct vm_area_struct, shared.linear.rb);
if (parent->shared.linear.rb_subtree_last < last)
parent->shared.linear.rb_subtree_last = last;
}
link = &parent->shared.linear.rb.rb_left;
}
vma->shared.linear.rb_subtree_last = last;
rb_link_node(&vma->shared.linear.rb, &parent->shared.linear.rb, link);
rb_insert_augmented(&vma->shared.linear.rb, &mapping->i_mmap,
&vma_interval_tree_augment_callbacks);
}

3
mm/memory-failure.c
View file

@ -431,7 +431,6 @@ static void collect_procs_file(struct page *page, struct list_head *to_kill,
{
struct vm_area_struct *vma;
struct task_struct *tsk;
struct prio_tree_iter iter;
struct address_space *mapping = page->mapping;
mutex_lock(&mapping->i_mmap_mutex);
@ -442,7 +441,7 @@ static void collect_procs_file(struct page *page, struct list_head *to_kill,
if (!task_early_kill(tsk))
continue;
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff,
vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff,
pgoff) {
/*
* Send early kill signal to tasks where a vma covers

9
mm/memory.c
View file

@ -2801,14 +2801,13 @@ static void unmap_mapping_range_vma(struct vm_area_struct *vma,
zap_page_range_single(vma, start_addr, end_addr - start_addr, details);
}
static inline void unmap_mapping_range_tree(struct prio_tree_root *root,
static inline void unmap_mapping_range_tree(struct rb_root *root,
struct zap_details *details)
{
struct vm_area_struct *vma;
struct prio_tree_iter iter;
pgoff_t vba, vea, zba, zea;
vma_prio_tree_foreach(vma, &iter, root,
vma_interval_tree_foreach(vma, root,
details->first_index, details->last_index) {
vba = vma->vm_pgoff;
@ -2839,7 +2838,7 @@ static inline void unmap_mapping_range_list(struct list_head *head,
* across *all* the pages in each nonlinear VMA, not just the pages
* whose virtual address lies outside the file truncation point.
*/
list_for_each_entry(vma, head, shared.vm_set.list) {
list_for_each_entry(vma, head, shared.nonlinear) {
details->nonlinear_vma = vma;
unmap_mapping_range_vma(vma, vma->vm_start, vma->vm_end, details);
}
@ -2883,7 +2882,7 @@ void unmap_mapping_range(struct address_space *mapping,
mutex_lock(&mapping->i_mmap_mutex);
if (unlikely(!prio_tree_empty(&mapping->i_mmap)))
if (unlikely(!RB_EMPTY_ROOT(&mapping->i_mmap)))
unmap_mapping_range_tree(&mapping->i_mmap, &details);
if (unlikely(!list_empty(&mapping->i_mmap_nonlinear)))
unmap_mapping_range_list(&mapping->i_mmap_nonlinear, &details);

22
mm/mmap.c
View file

@ -199,14 +199,14 @@ static void __remove_shared_vm_struct(struct vm_area_struct *vma,
flush_dcache_mmap_lock(mapping);
if (unlikely(vma->vm_flags & VM_NONLINEAR))
list_del_init(&vma->shared.vm_set.list);
list_del_init(&vma->shared.nonlinear);
else
vma_prio_tree_remove(vma, &mapping->i_mmap);
vma_interval_tree_remove(vma, &mapping->i_mmap);
flush_dcache_mmap_unlock(mapping);
}
/*
* Unlink a file-based vm structure from its prio_tree, to hide
* Unlink a file-based vm structure from its interval tree, to hide
* vma from rmap and vmtruncate before freeing its page tables.
*/
void unlink_file_vma(struct vm_area_struct *vma)
@ -411,7 +411,7 @@ static void __vma_link_file(struct vm_area_struct *vma)
if (unlikely(vma->vm_flags & VM_NONLINEAR))
vma_nonlinear_insert(vma, &mapping->i_mmap_nonlinear);
else
vma_prio_tree_insert(vma, &mapping->i_mmap);
vma_interval_tree_insert(vma, &mapping->i_mmap);
flush_dcache_mmap_unlock(mapping);
}
}
@ -449,7 +449,7 @@ static void vma_link(struct mm_struct *mm, struct vm_area_struct *vma,
/*
* Helper for vma_adjust() in the split_vma insert case: insert a vma into the
* mm's list and rbtree. It has already been inserted into the prio_tree.
* mm's list and rbtree. It has already been inserted into the interval tree.
*/
static void __insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
{
@ -491,7 +491,7 @@ int vma_adjust(struct vm_area_struct *vma, unsigned long start,
struct vm_area_struct *next = vma->vm_next;
struct vm_area_struct *importer = NULL;
struct address_space *mapping = NULL;
struct prio_tree_root *root = NULL;
struct rb_root *root = NULL;
struct anon_vma *anon_vma = NULL;
struct file *file = vma->vm_file;
long adjust_next = 0;
@ -554,7 +554,7 @@ again: remove_next = 1 + (end > next->vm_end);
mutex_lock(&mapping->i_mmap_mutex);
if (insert) {
/*
* Put into prio_tree now, so instantiated pages
* Put into interval tree now, so instantiated pages
* are visible to arm/parisc __flush_dcache_page
* throughout; but we cannot insert into address
* space until vma start or end is updated.
@ -582,9 +582,9 @@ again: remove_next = 1 + (end > next->vm_end);
if (root) {
flush_dcache_mmap_lock(mapping);
vma_prio_tree_remove(vma, root);
vma_interval_tree_remove(vma, root);
if (adjust_next)
vma_prio_tree_remove(next, root);
vma_interval_tree_remove(next, root);
}
vma->vm_start = start;
@ -597,8 +597,8 @@ again: remove_next = 1 + (end > next->vm_end);
if (root) {
if (adjust_next)
vma_prio_tree_insert(next, root);
vma_prio_tree_insert(vma, root);
vma_interval_tree_insert(next, root);
vma_interval_tree_insert(vma, root);
flush_dcache_mmap_unlock(mapping);
}

12
mm/nommu.c
View file

@ -698,7 +698,7 @@ static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma)
mutex_lock(&mapping->i_mmap_mutex);
flush_dcache_mmap_lock(mapping);
vma_prio_tree_insert(vma, &mapping->i_mmap);
vma_interval_tree_insert(vma, &mapping->i_mmap);
flush_dcache_mmap_unlock(mapping);
mutex_unlock(&mapping->i_mmap_mutex);
}
@ -764,7 +764,7 @@ static void delete_vma_from_mm(struct vm_area_struct *vma)
mutex_lock(&mapping->i_mmap_mutex);
flush_dcache_mmap_lock(mapping);
vma_prio_tree_remove(vma, &mapping->i_mmap);
vma_interval_tree_remove(vma, &mapping->i_mmap);
flush_dcache_mmap_unlock(mapping);
mutex_unlock(&mapping->i_mmap_mutex);
}
@ -2044,7 +2044,6 @@ int nommu_shrink_inode_mappings(struct inode *inode, size_t size,
size_t newsize)
{
struct vm_area_struct *vma;
struct prio_tree_iter iter;
struct vm_region *region;
pgoff_t low, high;
size_t r_size, r_top;
@ -2056,8 +2055,7 @@ int nommu_shrink_inode_mappings(struct inode *inode, size_t size,
mutex_lock(&inode->i_mapping->i_mmap_mutex);
/* search for VMAs that fall within the dead zone */
vma_prio_tree_foreach(vma, &iter, &inode->i_mapping->i_mmap,
low, high) {
vma_interval_tree_foreach(vma, &inode->i_mapping->i_mmap, low, high) {
/* found one - only interested if it's shared out of the page
* cache */
if (vma->vm_flags & VM_SHARED) {
@ -2073,8 +2071,8 @@ int nommu_shrink_inode_mappings(struct inode *inode, size_t size,
* we don't check for any regions that start beyond the EOF as there
* shouldn't be any
*/
vma_prio_tree_foreach(vma, &iter, &inode->i_mapping->i_mmap,
0, ULONG_MAX) {
vma_interval_tree_foreach(vma, &inode->i_mapping->i_mmap,
0, ULONG_MAX) {
if (!(vma->vm_flags & VM_SHARED))
continue;

208
mm/prio_tree.c
View file

@ -1,208 +0,0 @@
/*
* mm/prio_tree.c - priority search tree for mapping->i_mmap
*
* Copyright (C) 2004, Rajesh Venkatasubramanian <vrajesh@umich.edu>
*
* This file is released under the GPL v2.
*
* Based on the radix priority search tree proposed by Edward M. McCreight
* SIAM Journal of Computing, vol. 14, no.2, pages 257-276, May 1985
*
* 02Feb2004 Initial version
*/
#include <linux/mm.h>
#include <linux/prio_tree.h>
#include <linux/prefetch.h>
/*
* See lib/prio_tree.c for details on the general radix priority search tree
* code.
*/
/*
* The following #defines are mirrored from lib/prio_tree.c. They're only used
* for debugging, and should be removed (along with the debugging code using
* them) when switching also VMAs to the regular prio_tree code.
*/
#define RADIX_INDEX(vma) ((vma)->vm_pgoff)
#define VMA_SIZE(vma) (((vma)->vm_end - (vma)->vm_start) >> PAGE_SHIFT)
/* avoid overflow */
#define HEAP_INDEX(vma) ((vma)->vm_pgoff + (VMA_SIZE(vma) - 1))
/*
* Radix priority search tree for address_space->i_mmap
*
* For each vma that map a unique set of file pages i.e., unique [radix_index,
* heap_index] value, we have a corresponding priority search tree node. If
* multiple vmas have identical [radix_index, heap_index] value, then one of
* them is used as a tree node and others are stored in a vm_set list. The tree
* node points to the first vma (head) of the list using vm_set.head.
*
* prio_tree_root
* |
* A vm_set.head
* / \ /
* L R -> H-I-J-K-M-N-O-P-Q-S
* ^ ^ <-- vm_set.list -->
* tree nodes
*
* We need some way to identify whether a vma is a tree node, head of a vm_set
* list, or just a member of a vm_set list. We cannot use vm_flags to store
* such information. The reason is, in the above figure, it is possible that
* vm_flags' of R and H are covered by the different mmap_sems. When R is
* removed under R->mmap_sem, H replaces R as a tree node. Since we do not hold
* H->mmap_sem, we cannot use H->vm_flags for marking that H is a tree node now.
* That's why some trick involving shared.vm_set.parent is used for identifying
* tree nodes and list head nodes.
*
* vma radix priority search tree node rules:
*
* vma->shared.vm_set.parent != NULL ==> a tree node
* vma->shared.vm_set.head != NULL ==> list of others mapping same range
* vma->shared.vm_set.head == NULL ==> no others map the same range
*
* vma->shared.vm_set.parent == NULL
* vma->shared.vm_set.head != NULL ==> list head of vmas mapping same range
* vma->shared.vm_set.head == NULL ==> a list node
*/
/*
* Add a new vma known to map the same set of pages as the old vma:
* useful for fork's dup_mmap as well as vma_prio_tree_insert below.
* Note that it just happens to work correctly on i_mmap_nonlinear too.
*/
void vma_prio_tree_add(struct vm_area_struct *vma, struct vm_area_struct *old)
{
/* Leave these BUG_ONs till prio_tree patch stabilizes */
BUG_ON(RADIX_INDEX(vma) != RADIX_INDEX(old));
BUG_ON(HEAP_INDEX(vma) != HEAP_INDEX(old));
vma->shared.vm_set.head = NULL;
vma->shared.vm_set.parent = NULL;
if (!old->shared.vm_set.parent)
list_add(&vma->shared.vm_set.list,
&old->shared.vm_set.list);
else if (old->shared.vm_set.head)
list_add_tail(&vma->shared.vm_set.list,
&old->shared.vm_set.head->shared.vm_set.list);
else {
INIT_LIST_HEAD(&vma->shared.vm_set.list);
vma->shared.vm_set.head = old;
old->shared.vm_set.head = vma;
}
}
void vma_prio_tree_insert(struct vm_area_struct *vma,
struct prio_tree_root *root)
{
struct prio_tree_node *ptr;
struct vm_area_struct *old;
vma->shared.vm_set.head = NULL;
ptr = raw_prio_tree_insert(root, &vma->shared.prio_tree_node);
if (ptr != (struct prio_tree_node *) &vma->shared.prio_tree_node) {
old = prio_tree_entry(ptr, struct vm_area_struct,
shared.prio_tree_node);
vma_prio_tree_add(vma, old);
}
}
void vma_prio_tree_remove(struct vm_area_struct *vma,
struct prio_tree_root *root)
{
struct vm_area_struct *node, *head, *new_head;
if (!vma->shared.vm_set.head) {
if (!vma->shared.vm_set.parent)
list_del_init(&vma->shared.vm_set.list);
else
raw_prio_tree_remove(root, &vma->shared.prio_tree_node);
} else {
/* Leave this BUG_ON till prio_tree patch stabilizes */
BUG_ON(vma->shared.vm_set.head->shared.vm_set.head != vma);
if (vma->shared.vm_set.parent) {
head = vma->shared.vm_set.head;
if (!list_empty(&head->shared.vm_set.list)) {
new_head = list_entry(
head->shared.vm_set.list.next,
struct vm_area_struct,
shared.vm_set.list);
list_del_init(&head->shared.vm_set.list);
} else
new_head = NULL;
raw_prio_tree_replace(root, &vma->shared.prio_tree_node,
&head->shared.prio_tree_node);
head->shared.vm_set.head = new_head;
if (new_head)
new_head->shared.vm_set.head = head;
} else {
node = vma->shared.vm_set.head;
if (!list_empty(&vma->shared.vm_set.list)) {
new_head = list_entry(
vma->shared.vm_set.list.next,
struct vm_area_struct,
shared.vm_set.list);
list_del_init(&vma->shared.vm_set.list);
node->shared.vm_set.head = new_head;
new_head->shared.vm_set.head = node;
} else
node->shared.vm_set.head = NULL;
}
}
}
/*
* Helper function to enumerate vmas that map a given file page or a set of
* contiguous file pages. The function returns vmas that at least map a single
* page in the given range of contiguous file pages.
*/
struct vm_area_struct *vma_prio_tree_next(struct vm_area_struct *vma,
struct prio_tree_iter *iter)
{
struct prio_tree_node *ptr;
struct vm_area_struct *next;
if (!vma) {
/*
* First call is with NULL vma
*/
ptr = prio_tree_next(iter);
if (ptr) {
next = prio_tree_entry(ptr, struct vm_area_struct,
shared.prio_tree_node);
prefetch(next->shared.vm_set.head);
return next;
} else
return NULL;
}
if (vma->shared.vm_set.parent) {
if (vma->shared.vm_set.head) {
next = vma->shared.vm_set.head;
prefetch(next->shared.vm_set.list.next);
return next;
}
} else {
next = list_entry(vma->shared.vm_set.list.next,
struct vm_area_struct, shared.vm_set.list);
if (!next->shared.vm_set.head) {
prefetch(next->shared.vm_set.list.next);
return next;
}
}
ptr = prio_tree_next(iter);
if (ptr) {
next = prio_tree_entry(ptr, struct vm_area_struct,
shared.prio_tree_node);
prefetch(next->shared.vm_set.head);
return next;
} else
return NULL;
}

18
mm/rmap.c
View file

@ -820,7 +820,6 @@ static int page_referenced_file(struct page *page,
struct address_space *mapping = page->mapping;
pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
struct vm_area_struct *vma;
struct prio_tree_iter iter;
int referenced = 0;
/*
@ -846,7 +845,7 @@ static int page_referenced_file(struct page *page,
*/
mapcount = page_mapcount(page);
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
unsigned long address = vma_address(page, vma);
if (address == -EFAULT)
continue;
@ -945,13 +944,12 @@ static int page_mkclean_file(struct address_space *mapping, struct page *page)
{
pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
struct vm_area_struct *vma;
struct prio_tree_iter iter;
int ret = 0;
BUG_ON(PageAnon(page));
mutex_lock(&mapping->i_mmap_mutex);
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
if (vma->vm_flags & VM_SHARED) {
unsigned long address = vma_address(page, vma);
if (address == -EFAULT)
@ -1547,7 +1545,6 @@ static int try_to_unmap_file(struct page *page, enum ttu_flags flags)
struct address_space *mapping = page->mapping;
pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
struct vm_area_struct *vma;
struct prio_tree_iter iter;
int ret = SWAP_AGAIN;
unsigned long cursor;
unsigned long max_nl_cursor = 0;
@ -1555,7 +1552,7 @@ static int try_to_unmap_file(struct page *page, enum ttu_flags flags)
unsigned int mapcount;
mutex_lock(&mapping->i_mmap_mutex);
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
unsigned long address = vma_address(page, vma);
if (address == -EFAULT)
continue;
@ -1576,7 +1573,7 @@ static int try_to_unmap_file(struct page *page, enum ttu_flags flags)
goto out;
list_for_each_entry(vma, &mapping->i_mmap_nonlinear,
shared.vm_set.list) {
shared.nonlinear) {
cursor = (unsigned long) vma->vm_private_data;
if (cursor > max_nl_cursor)
max_nl_cursor = cursor;
@ -1608,7 +1605,7 @@ static int try_to_unmap_file(struct page *page, enum ttu_flags flags)
do {
list_for_each_entry(vma, &mapping->i_mmap_nonlinear,
shared.vm_set.list) {
shared.nonlinear) {
cursor = (unsigned long) vma->vm_private_data;
while ( cursor < max_nl_cursor &&
cursor < vma->vm_end - vma->vm_start) {
@ -1631,7 +1628,7 @@ static int try_to_unmap_file(struct page *page, enum ttu_flags flags)
* in locked vmas). Reset cursor on all unreserved nonlinear
* vmas, now forgetting on which ones it had fallen behind.
*/
list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list)
list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.nonlinear)
vma->vm_private_data = NULL;
out:
mutex_unlock(&mapping->i_mmap_mutex);
@ -1748,13 +1745,12 @@ static int rmap_walk_file(struct page *page, int (*rmap_one)(struct page *,
struct address_space *mapping = page->mapping;
pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
struct vm_area_struct *vma;
struct prio_tree_iter iter;
int ret = SWAP_AGAIN;
if (!mapping)
return ret;
mutex_lock(&mapping->i_mmap_mutex);
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
unsigned long address = vma_address(page, vma);
if (address == -EFAULT)
continue;