[patch 07/10] mm + fs: store shadow entries in page cache

From: Johannes Weiner
Date: Mon Feb 03 2014 - 20:00:09 EST

Reclaim will be leaving shadow entries in the page cache radix tree
upon evicting the real page. As those pages are found from the LRU,
an iput() can lead to the inode being freed concurrently. At this
point, reclaim must no longer install shadow pages because the inode
freeing code needs to ensure the page tree is really empty.

Add an address_space flag, AS_EXITING, that the inode freeing code
sets under the tree lock before doing the final truncate. Reclaim
will check for this flag before installing shadow pages.

Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Reviewed-by: Rik van Riel <riel@xxxxxxxxxx>
Reviewed-by: Minchan Kim <minchan@xxxxxxxxxx>
---
Documentation/filesystems/porting | 6 +--
drivers/staging/lustre/lustre/llite/llite_lib.c | 2 +-
fs/9p/vfs_inode.c | 2 +-
fs/affs/inode.c | 2 +-
fs/afs/inode.c | 2 +-
fs/bfs/inode.c | 2 +-
fs/block_dev.c | 4 +-
fs/btrfs/inode.c | 2 +-
fs/cifs/cifsfs.c | 2 +-
fs/coda/inode.c | 2 +-
fs/ecryptfs/super.c | 2 +-
fs/exofs/inode.c | 2 +-
fs/ext2/inode.c | 2 +-
fs/ext3/inode.c | 2 +-
fs/ext4/inode.c | 4 +-
fs/f2fs/inode.c | 2 +-
fs/fat/inode.c | 2 +-
fs/freevxfs/vxfs_inode.c | 2 +-
fs/fuse/inode.c | 2 +-
fs/gfs2/super.c | 2 +-
fs/hfs/inode.c | 2 +-
fs/hfsplus/super.c | 2 +-
fs/hostfs/hostfs_kern.c | 2 +-
fs/hpfs/inode.c | 2 +-
fs/inode.c | 4 +-
fs/jffs2/fs.c | 2 +-
fs/jfs/inode.c | 4 +-
fs/kernfs/inode.c | 2 +-
fs/logfs/readwrite.c | 2 +-
fs/minix/inode.c | 2 +-
fs/ncpfs/inode.c | 2 +-
fs/nfs/inode.c | 2 +-
fs/nfs/nfs4super.c | 2 +-
fs/nilfs2/inode.c | 6 +--
fs/ntfs/inode.c | 2 +-
fs/ocfs2/inode.c | 4 +-
fs/omfs/inode.c | 2 +-
fs/proc/inode.c | 2 +-
fs/reiserfs/inode.c | 2 +-
fs/sysv/inode.c | 2 +-
fs/ubifs/super.c | 2 +-
fs/udf/inode.c | 4 +-
fs/ufs/inode.c | 2 +-
fs/xfs/xfs_super.c | 2 +-
include/linux/fs.h | 1 +
include/linux/mm.h | 1 +
include/linux/pagemap.h | 13 +++++-
mm/filemap.c | 33 ++++++++++++---
mm/truncate.c | 54 +++++++++++++++++++++++--
mm/vmscan.c | 2 +-
50 files changed, 147 insertions(+), 65 deletions(-)

diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting
index fe2b7ae6f962..0f3a1390bf00 100644
--- a/Documentation/filesystems/porting
+++ b/Documentation/filesystems/porting
@@ -295,9 +295,9 @@ in the beginning of ->setattr unconditionally.
->clear_inode() and ->delete_inode() are gone; ->evict_inode() should
be used instead. It gets called whenever the inode is evicted, whether it has
remaining links or not. Caller does *not* evict the pagecache or inode-associated
-metadata buffers; getting rid of those is responsibility of method, as it had
-been for ->delete_inode(). Caller makes sure async writeback cannot be running
-for the inode while (or after) ->evict_inode() is called.
+metadata buffers; the method has to use truncate_inode_pages_final() to get rid
+of those. Caller makes sure async writeback cannot be running for the inode while
+(or after) ->evict_inode() is called.

->drop_inode() returns int now; it's called on final iput() with
inode->i_lock held and it returns true if filesystems wants the inode to be
diff --git a/drivers/staging/lustre/lustre/llite/llite_lib.c b/drivers/staging/lustre/lustre/llite/llite_lib.c
index 6cfdb9e4b74b..fc6aac3cfe00 100644
--- a/drivers/staging/lustre/lustre/llite/llite_lib.c
+++ b/drivers/staging/lustre/lustre/llite/llite_lib.c
@@ -1877,7 +1877,7 @@ void ll_delete_inode(struct inode *inode)
cl_sync_file_range(inode, 0, OBD_OBJECT_EOF,
CL_FSYNC_DISCARD, 1);

- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);

/* Workaround for LU-118 */
if (inode->i_data.nrpages) {
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index bb7991c7e5c7..53161ec058a7 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -451,7 +451,7 @@ void v9fs_evict_inode(struct inode *inode)
{
struct v9fs_inode *v9inode = V9FS_I(inode);

- truncate_inode_pages(inode->i_mapping, 0);
+ truncate_inode_pages_final(inode->i_mapping);
clear_inode(inode);
filemap_fdatawrite(inode->i_mapping);

diff --git a/fs/affs/inode.c b/fs/affs/inode.c
index 0e092d08680e..96df91e8c334 100644
--- a/fs/affs/inode.c
+++ b/fs/affs/inode.c
@@ -259,7 +259,7 @@ affs_evict_inode(struct inode *inode)
{
unsigned long cache_page;
pr_debug("AFFS: evict_inode(ino=%lu, nlink=%u)\n", inode->i_ino, inode->i_nlink);
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);

if (!inode->i_nlink) {
inode->i_size = 0;
diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index ce25d755b7aa..294671288449 100644
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -422,7 +422,7 @@ void afs_evict_inode(struct inode *inode)

ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);

- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);

afs_give_up_callback(vnode);
diff --git a/fs/bfs/inode.c b/fs/bfs/inode.c
index 8defc6b3f9a2..29aa5cf6639b 100644
--- a/fs/bfs/inode.c
+++ b/fs/bfs/inode.c
@@ -172,7 +172,7 @@ static void bfs_evict_inode(struct inode *inode)

dprintf("ino=%08lx\n", ino);

- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
invalidate_inode_buffers(inode);
clear_inode(inode);

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 1e86823a9cbd..c7a7def27b07 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -83,7 +83,7 @@ void kill_bdev(struct block_device *bdev)
{
struct address_space *mapping = bdev->bd_inode->i_mapping;

- if (mapping->nrpages == 0)
+ if (mapping->nrpages == 0 && mapping->nrshadows == 0)
return;

invalidate_bh_lrus();
@@ -419,7 +419,7 @@ static void bdev_evict_inode(struct inode *inode)
{
struct block_device *bdev = &BDEV_I(inode)->bdev;
struct list_head *p;
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
invalidate_inode_buffers(inode); /* is it needed here? */
clear_inode(inode);
spin_lock(&bdev_lock);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 5c4ab9c18940..c73f67c8dbc7 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4593,7 +4593,7 @@ static void evict_inode_truncate_pages(struct inode *inode)
struct rb_node *node;

ASSERT(inode->i_state & I_FREEING);
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);

write_lock(&map_tree->lock);
while (!RB_EMPTY_ROOT(&map_tree->map)) {
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 849f6132b327..d23ae08f7bca 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -286,7 +286,7 @@ cifs_destroy_inode(struct inode *inode)
static void
cifs_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
cifs_fscache_release_inode_cookie(inode);
}
diff --git a/fs/coda/inode.c b/fs/coda/inode.c
index 506de34a4ef3..62618ec9356c 100644
--- a/fs/coda/inode.c
+++ b/fs/coda/inode.c
@@ -250,7 +250,7 @@ static void coda_put_super(struct super_block *sb)

static void coda_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
coda_cache_clear_inode(inode);
}
diff --git a/fs/ecryptfs/super.c b/fs/ecryptfs/super.c
index e879cf8ff0b1..afa1b81c3418 100644
--- a/fs/ecryptfs/super.c
+++ b/fs/ecryptfs/super.c
@@ -132,7 +132,7 @@ static int ecryptfs_statfs(struct dentry *dentry, struct kstatfs *buf)
*/
static void ecryptfs_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
iput(ecryptfs_inode_to_lower(inode));
}
diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c
index ee4317faccb1..d1c244d67667 100644
--- a/fs/exofs/inode.c
+++ b/fs/exofs/inode.c
@@ -1486,7 +1486,7 @@ void exofs_evict_inode(struct inode *inode)
struct ore_io_state *ios;
int ret;

- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);

/* TODO: should do better here */
if (inode->i_nlink || is_bad_inode(inode))
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 94ed36849b71..b1d2a4675d42 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -78,7 +78,7 @@ void ext2_evict_inode(struct inode * inode)
dquot_drop(inode);
}

- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);

if (want_delete) {
sb_start_intwrite(inode->i_sb);
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index 384b6ebb655f..efce2bbfb5e5 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -228,7 +228,7 @@ void ext3_evict_inode (struct inode *inode)
log_wait_commit(journal, commit_tid);
filemap_write_and_wait(&inode->i_data);
}
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);

ext3_discard_reservation(inode);
rsv = ei->i_block_alloc_info;
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 6e39895a91b8..7e83b4a1ae00 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -214,7 +214,7 @@ void ext4_evict_inode(struct inode *inode)
jbd2_complete_transaction(journal, commit_tid);
filemap_write_and_wait(&inode->i_data);
}
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);

WARN_ON(atomic_read(&EXT4_I(inode)->i_ioend_count));
goto no_delete;
@@ -225,7 +225,7 @@ void ext4_evict_inode(struct inode *inode)

if (ext4_should_order_data(inode))
ext4_begin_ordered_truncate(inode, 0);
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);

WARN_ON(atomic_read(&EXT4_I(inode)->i_ioend_count));
if (is_bad_inode(inode))
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 4d67ed736dca..28cea76d78c6 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -260,7 +260,7 @@ void f2fs_evict_inode(struct inode *inode)
struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);

trace_f2fs_evict_inode(inode);
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);

if (inode->i_ino == F2FS_NODE_INO(sbi) ||
inode->i_ino == F2FS_META_INO(sbi))
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 854b578f6695..c68d9f27135e 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -490,7 +490,7 @@ EXPORT_SYMBOL_GPL(fat_build_inode);

static void fat_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
if (!inode->i_nlink) {
inode->i_size = 0;
fat_truncate_blocks(inode, 0);
diff --git a/fs/freevxfs/vxfs_inode.c b/fs/freevxfs/vxfs_inode.c
index f47df72cef17..363e3ae25f6b 100644
--- a/fs/freevxfs/vxfs_inode.c
+++ b/fs/freevxfs/vxfs_inode.c
@@ -354,7 +354,7 @@ static void vxfs_i_callback(struct rcu_head *head)
void
vxfs_evict_inode(struct inode *ip)
{
- truncate_inode_pages(&ip->i_data, 0);
+ truncate_inode_pages_final(&ip->i_data);
clear_inode(ip);
call_rcu(&ip->i_rcu, vxfs_i_callback);
}
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index d468643a68b2..9c761b611c54 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -123,7 +123,7 @@ static void fuse_destroy_inode(struct inode *inode)

static void fuse_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
if (inode->i_sb->s_flags & MS_ACTIVE) {
struct fuse_conn *fc = get_fuse_conn(inode);
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 60f60f6181f3..24410cd9a82a 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -1558,7 +1558,7 @@ out_unlock:
fs_warn(sdp, "gfs2_evict_inode: %d\n", error);
out:
/* Case 3 starts here */
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
gfs2_rs_delete(ip, NULL);
gfs2_ordered_del_inode(ip);
clear_inode(inode);
diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c
index 380ab31b5e0f..9e2fecd62f62 100644
--- a/fs/hfs/inode.c
+++ b/fs/hfs/inode.c
@@ -547,7 +547,7 @@ out:

void hfs_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
if (HFS_IS_RSRC(inode) && HFS_I(inode)->rsrc_inode) {
HFS_I(HFS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c
index 80875aa640ef..a6abf87d79d0 100644
--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -161,7 +161,7 @@ static int hfsplus_write_inode(struct inode *inode,
static void hfsplus_evict_inode(struct inode *inode)
{
hfs_dbg(INODE, "hfsplus_evict_inode: %lu\n", inode->i_ino);
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
if (HFSPLUS_IS_RSRC(inode)) {
HFSPLUS_I(HFSPLUS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index fe649d325b1f..9c470fde9878 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -230,7 +230,7 @@ static struct inode *hostfs_alloc_inode(struct super_block *sb)

static void hostfs_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
if (HOSTFS_I(inode)->fd != -1) {
close_file(&HOSTFS_I(inode)->fd);
diff --git a/fs/hpfs/inode.c b/fs/hpfs/inode.c
index 9edeeb0ea97e..50a427313835 100644
--- a/fs/hpfs/inode.c
+++ b/fs/hpfs/inode.c
@@ -304,7 +304,7 @@ void hpfs_write_if_changed(struct inode *inode)

void hpfs_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
if (!inode->i_nlink) {
hpfs_lock(inode->i_sb);
diff --git a/fs/inode.c b/fs/inode.c
index 4bcdad3c9361..e6905152c39f 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -503,6 +503,7 @@ void clear_inode(struct inode *inode)
*/
spin_lock_irq(&inode->i_data.tree_lock);
BUG_ON(inode->i_data.nrpages);
+ BUG_ON(inode->i_data.nrshadows);
spin_unlock_irq(&inode->i_data.tree_lock);
BUG_ON(!list_empty(&inode->i_data.private_list));
BUG_ON(!(inode->i_state & I_FREEING));
@@ -548,8 +549,7 @@ static void evict(struct inode *inode)
if (op->evict_inode) {
op->evict_inode(inode);
} else {
- if (inode->i_data.nrpages)
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
}
if (S_ISBLK(inode->i_mode) && inode->i_bdev)
diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index a69e426435dd..a012e16a8bb3 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -242,7 +242,7 @@ void jffs2_evict_inode (struct inode *inode)

jffs2_dbg(1, "%s(): ino #%lu mode %o\n",
__func__, inode->i_ino, inode->i_mode);
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
jffs2_do_clear_inode(c, f);
}
diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c
index f4aab719add5..6f8fe72c2a7a 100644
--- a/fs/jfs/inode.c
+++ b/fs/jfs/inode.c
@@ -154,7 +154,7 @@ void jfs_evict_inode(struct inode *inode)
dquot_initialize(inode);

if (JFS_IP(inode)->fileset == FILESYSTEM_I) {
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);

if (test_cflag(COMMIT_Freewmap, inode))
jfs_free_zero_link(inode);
@@ -168,7 +168,7 @@ void jfs_evict_inode(struct inode *inode)
dquot_free_inode(inode);
}
} else {
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
}
clear_inode(inode);
dquot_drop(inode);
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index e55126f85bd2..abb0f1f53d93 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -355,7 +355,7 @@ void kernfs_evict_inode(struct inode *inode)
{
struct kernfs_node *kn = inode->i_private;

- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
kernfs_put(kn);
}
diff --git a/fs/logfs/readwrite.c b/fs/logfs/readwrite.c
index 9a59cbade2fb..48140315f627 100644
--- a/fs/logfs/readwrite.c
+++ b/fs/logfs/readwrite.c
@@ -2180,7 +2180,7 @@ void logfs_evict_inode(struct inode *inode)
do_delete_inode(inode);
}
}
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);

/* Cheaper version of write_inode. All changes are concealed in
diff --git a/fs/minix/inode.c b/fs/minix/inode.c
index 0332109162a5..03aaeb1a694a 100644
--- a/fs/minix/inode.c
+++ b/fs/minix/inode.c
@@ -26,7 +26,7 @@ static int minix_remount (struct super_block * sb, int * flags, char * data);

static void minix_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
if (!inode->i_nlink) {
inode->i_size = 0;
minix_truncate(inode);
diff --git a/fs/ncpfs/inode.c b/fs/ncpfs/inode.c
index 2cf2ebecb55f..ee59d35ff069 100644
--- a/fs/ncpfs/inode.c
+++ b/fs/ncpfs/inode.c
@@ -296,7 +296,7 @@ ncp_iget(struct super_block *sb, struct ncp_entry_info *info)
static void
ncp_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);

if (S_ISDIR(inode->i_mode)) {
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 28a0a3cbd3b7..a2494b616951 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -128,7 +128,7 @@ EXPORT_SYMBOL_GPL(nfs_clear_inode);

void nfs_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
nfs_clear_inode(inode);
}
diff --git a/fs/nfs/nfs4super.c b/fs/nfs/nfs4super.c
index 808f29574412..6f340f02f2ba 100644
--- a/fs/nfs/nfs4super.c
+++ b/fs/nfs/nfs4super.c
@@ -90,7 +90,7 @@ static int nfs4_write_inode(struct inode *inode, struct writeback_control *wbc)
*/
static void nfs4_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
pnfs_return_layout(inode);
pnfs_destroy_layout(NFS_I(inode));
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 7e350c562e0e..b9c5726120e3 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -783,16 +783,14 @@ void nilfs_evict_inode(struct inode *inode)
int ret;

if (inode->i_nlink || !ii->i_root || unlikely(is_bad_inode(inode))) {
- if (inode->i_data.nrpages)
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
nilfs_clear_inode(inode);
return;
}
nilfs_transaction_begin(sb, &ti, 0); /* never fails */

- if (inode->i_data.nrpages)
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);

/* TODO: some of the following operations may fail. */
nilfs_truncate_bmap(ii, 0);
diff --git a/fs/ntfs/inode.c b/fs/ntfs/inode.c
index ffb9b3675736..9d8153ebacfb 100644
--- a/fs/ntfs/inode.c
+++ b/fs/ntfs/inode.c
@@ -2259,7 +2259,7 @@ void ntfs_evict_big_inode(struct inode *vi)
{
ntfs_inode *ni = NTFS_I(vi);

- truncate_inode_pages(&vi->i_data, 0);
+ truncate_inode_pages_final(&vi->i_data);
clear_inode(vi);

#ifdef NTFS_RW
diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index f29a90fde619..a11bfffbbc29 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -941,7 +941,7 @@ static void ocfs2_cleanup_delete_inode(struct inode *inode,
(unsigned long long)OCFS2_I(inode)->ip_blkno, sync_data);
if (sync_data)
filemap_write_and_wait(inode->i_mapping);
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
}

static void ocfs2_delete_inode(struct inode *inode)
@@ -1157,7 +1157,7 @@ void ocfs2_evict_inode(struct inode *inode)
(OCFS2_I(inode)->ip_flags & OCFS2_INODE_MAYBE_ORPHANED)) {
ocfs2_delete_inode(inode);
} else {
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
}
ocfs2_clear_inode(inode);
}
diff --git a/fs/omfs/inode.c b/fs/omfs/inode.c
index d8b0afde2179..ec58c7659183 100644
--- a/fs/omfs/inode.c
+++ b/fs/omfs/inode.c
@@ -183,7 +183,7 @@ int omfs_sync_inode(struct inode *inode)
*/
static void omfs_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);

if (inode->i_nlink)
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 124fc43c7090..8f20e3404fd2 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -35,7 +35,7 @@ static void proc_evict_inode(struct inode *inode)
const struct proc_ns_operations *ns_ops;
void *ns;

- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);

/* Stop tracking associated processes */
diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c
index ad62bdbb451e..bc8b8009897d 100644
--- a/fs/reiserfs/inode.c
+++ b/fs/reiserfs/inode.c
@@ -35,7 +35,7 @@ void reiserfs_evict_inode(struct inode *inode)
if (!inode->i_nlink && !is_bad_inode(inode))
dquot_initialize(inode);

- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
if (inode->i_nlink)
goto no_delete;

diff --git a/fs/sysv/inode.c b/fs/sysv/inode.c
index c327d4ee1235..5625ca920f5e 100644
--- a/fs/sysv/inode.c
+++ b/fs/sysv/inode.c
@@ -295,7 +295,7 @@ int sysv_sync_inode(struct inode *inode)

static void sysv_evict_inode(struct inode *inode)
{
- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
if (!inode->i_nlink) {
inode->i_size = 0;
sysv_truncate(inode);
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 5ded8490c0c6..48f943f7f5d5 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -351,7 +351,7 @@ static void ubifs_evict_inode(struct inode *inode)
dbg_gen("inode %lu, mode %#x", inode->i_ino, (int)inode->i_mode);
ubifs_assert(!atomic_read(&inode->i_count));

- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);

if (inode->i_nlink)
goto done;
diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index 062b7925bca0..af6f4c38d91a 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -146,8 +146,8 @@ void udf_evict_inode(struct inode *inode)
want_delete = 1;
udf_setsize(inode, 0);
udf_update_inode(inode, IS_SYNC(inode));
- } else
- truncate_inode_pages(&inode->i_data, 0);
+ }
+ truncate_inode_pages_final(&inode->i_data);
invalidate_inode_buffers(inode);
clear_inode(inode);
if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB &&
diff --git a/fs/ufs/inode.c b/fs/ufs/inode.c
index c8ca96086784..61e8a9b021dd 100644
--- a/fs/ufs/inode.c
+++ b/fs/ufs/inode.c
@@ -885,7 +885,7 @@ void ufs_evict_inode(struct inode * inode)
if (!inode->i_nlink && !is_bad_inode(inode))
want_delete = 1;

- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
if (want_delete) {
loff_t old_i_size;
/*UFS_I(inode)->i_dtime = CURRENT_TIME;*/
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index f317488263dd..01ee44444885 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -996,7 +996,7 @@ xfs_fs_evict_inode(

trace_xfs_evict_inode(ip);

- truncate_inode_pages(&inode->i_data, 0);
+ truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
XFS_STATS_INC(vn_rele);
XFS_STATS_INC(vn_remove);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 09f553c59813..6491bd6c313f 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -416,6 +416,7 @@ struct address_space {
struct mutex i_mmap_mutex; /* protect tree, count, list */
/* Protected by tree_lock together with the radix tree */
unsigned long nrpages; /* number of total pages */
+ unsigned long nrshadows; /* number of shadow entries */
pgoff_t writeback_index;/* writeback starts here */
const struct address_space_operations *a_ops; /* methods */
unsigned long flags; /* error bits/gfp mask */
diff --git a/include/linux/mm.h b/include/linux/mm.h
index d684ac125482..ad26f7b49b1a 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1815,6 +1815,7 @@ vm_unmapped_area(struct vm_unmapped_area_info *info)
extern void truncate_inode_pages(struct address_space *, loff_t);
extern void truncate_inode_pages_range(struct address_space *,
loff_t lstart, loff_t lend);
+extern void truncate_inode_pages_final(struct address_space *);

/* generic vm_area_ops exported for stackable file systems */
extern int filemap_fault(struct vm_area_struct *, struct vm_fault *);
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 2eeca3c83b0f..e7729734156e 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -25,6 +25,7 @@ enum mapping_flags {
AS_MM_ALL_LOCKS = __GFP_BITS_SHIFT + 2, /* under mm_take_all_locks() */
AS_UNEVICTABLE = __GFP_BITS_SHIFT + 3, /* e.g., ramdisk, SHM_LOCK */
AS_BALLOON_MAP = __GFP_BITS_SHIFT + 4, /* balloon page special map */
+ AS_EXITING = __GFP_BITS_SHIFT + 5, /* final truncate in progress */
};

static inline void mapping_set_error(struct address_space *mapping, int error)
@@ -69,6 +70,16 @@ static inline int mapping_balloon(struct address_space *mapping)
return mapping && test_bit(AS_BALLOON_MAP, &mapping->flags);
}

+static inline void mapping_set_exiting(struct address_space *mapping)
+{
+ set_bit(AS_EXITING, &mapping->flags);
+}
+
+static inline int mapping_exiting(struct address_space *mapping)
+{
+ return test_bit(AS_EXITING, &mapping->flags);
+}
+
static inline gfp_t mapping_gfp_mask(struct address_space * mapping)
{
return (__force gfp_t)mapping->flags & __GFP_BITS_MASK;
@@ -547,7 +558,7 @@ int add_to_page_cache_locked(struct page *page, struct address_space *mapping,
int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
pgoff_t index, gfp_t gfp_mask);
extern void delete_from_page_cache(struct page *page);
-extern void __delete_from_page_cache(struct page *page);
+extern void __delete_from_page_cache(struct page *page, void *shadow);
int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask);

/*
diff --git a/mm/filemap.c b/mm/filemap.c
index a194179303e5..18f80d418f83 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -107,12 +107,33 @@
* ->tasklist_lock (memory_failure, collect_procs_ao)
*/

+static void page_cache_tree_delete(struct address_space *mapping,
+ struct page *page, void *shadow)
+{
+ if (shadow) {
+ void **slot;
+
+ slot = radix_tree_lookup_slot(&mapping->page_tree, page->index);
+ radix_tree_replace_slot(slot, shadow);
+ mapping->nrshadows++;
+ /*
+ * Make sure the nrshadows update is committed before
+ * the nrpages update so that final truncate racing
+ * with reclaim does not see both counters 0 at the
+ * same time and miss a shadow entry.
+ */
+ smp_wmb();
+ } else
+ radix_tree_delete(&mapping->page_tree, page->index);
+ mapping->nrpages--;
+}
+
/*
* Delete a page from the page cache and free it. Caller has to make
* sure the page is locked and that nobody else uses it - or that usage
* is safe. The caller must hold the mapping's tree_lock.
*/
-void __delete_from_page_cache(struct page *page)
+void __delete_from_page_cache(struct page *page, void *shadow)
{
struct address_space *mapping = page->mapping;

@@ -127,10 +148,11 @@ void __delete_from_page_cache(struct page *page)
else
cleancache_invalidate_page(mapping, page);

- radix_tree_delete(&mapping->page_tree, page->index);
+ page_cache_tree_delete(mapping, page, shadow);
+
page->mapping = NULL;
/* Leave page->index set: truncation lookup relies upon it */
- mapping->nrpages--;
+
__dec_zone_page_state(page, NR_FILE_PAGES);
if (PageSwapBacked(page))
__dec_zone_page_state(page, NR_SHMEM);
@@ -166,7 +188,7 @@ void delete_from_page_cache(struct page *page)

freepage = mapping->a_ops->freepage;
spin_lock_irq(&mapping->tree_lock);
- __delete_from_page_cache(page);
+ __delete_from_page_cache(page, NULL);
spin_unlock_irq(&mapping->tree_lock);
mem_cgroup_uncharge_cache_page(page);

@@ -426,7 +448,7 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask)
new->index = offset;

spin_lock_irq(&mapping->tree_lock);
- __delete_from_page_cache(old);
+ __delete_from_page_cache(old, NULL);
error = radix_tree_insert(&mapping->page_tree, offset, new);
BUG_ON(error);
mapping->nrpages++;
@@ -460,6 +482,7 @@ static int page_cache_tree_insert(struct address_space *mapping,
if (!radix_tree_exceptional_entry(p))
return -EEXIST;
radix_tree_replace_slot(slot, page);
+ mapping->nrshadows--;
mapping->nrpages++;
return 0;
}
diff --git a/mm/truncate.c b/mm/truncate.c
index b0f4d4bee8ab..4ca425e5db58 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -35,7 +35,8 @@ static void clear_exceptional_entry(struct address_space *mapping,
* without the tree itself locked. These unlocked entries
* need verification under the tree lock.
*/
- radix_tree_delete_item(&mapping->page_tree, index, entry);
+ if (radix_tree_delete_item(&mapping->page_tree, index, entry) == entry)
+ mapping->nrshadows--;
spin_unlock_irq(&mapping->tree_lock);
}

@@ -229,7 +230,7 @@ void truncate_inode_pages_range(struct address_space *mapping,
int i;

cleancache_invalidate_inode(mapping);
- if (mapping->nrpages == 0)
+ if (mapping->nrpages == 0 && mapping->nrshadows == 0)
return;

/* Offsets within partial pages */
@@ -391,6 +392,53 @@ void truncate_inode_pages(struct address_space *mapping, loff_t lstart)
EXPORT_SYMBOL(truncate_inode_pages);

/**
+ * truncate_inode_pages_final - truncate *all* pages before inode dies
+ * @mapping: mapping to truncate
+ *
+ * Called under (and serialized by) inode->i_mutex.
+ *
+ * Filesystems have to use this in the .evict_inode path to inform the
+ * VM that this is the final truncate and the inode is going away.
+ */
+void truncate_inode_pages_final(struct address_space *mapping)
+{
+ unsigned long nrshadows;
+ unsigned long nrpages;
+
+ /*
+ * Page reclaim can not participate in regular inode lifetime
+ * management (can't call iput()) and thus can race with the
+ * inode teardown. Tell it when the address space is exiting,
+ * so that it does not install eviction information after the
+ * final truncate has begun.
+ */
+ mapping_set_exiting(mapping);
+
+ /*
+ * When reclaim installs eviction entries, it increases
+ * nrshadows first, then decreases nrpages. Make sure we see
+ * this in the right order or we might miss an entry.
+ */
+ nrpages = mapping->nrpages;
+ smp_rmb();
+ nrshadows = mapping->nrshadows;
+
+ if (nrpages || nrshadows) {
+ /*
+ * As truncation uses a lockless tree lookup, cycle
+ * the tree lock to make sure any ongoing tree
+ * modification that does not see AS_EXITING is
+ * completed before starting the final truncate.
+ */
+ spin_lock_irq(&mapping->tree_lock);
+ spin_unlock_irq(&mapping->tree_lock);
+
+ truncate_inode_pages(mapping, 0);
+ }
+}
+EXPORT_SYMBOL(truncate_inode_pages_final);
+
+/**
* invalidate_mapping_pages - Invalidate all the unlocked pages of one inode
* @mapping: the address_space which holds the pages to invalidate
* @start: the offset 'from' which to invalidate
@@ -483,7 +531,7 @@ invalidate_complete_page2(struct address_space *mapping, struct page *page)
goto failed;

BUG_ON(page_has_private(page));
- __delete_from_page_cache(page);
+ __delete_from_page_cache(page, NULL);
spin_unlock_irq(&mapping->tree_lock);
mem_cgroup_uncharge_cache_page(page);

diff --git a/mm/vmscan.c b/mm/vmscan.c
index a9c74b409681..63712938169b 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -572,7 +572,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page)

freepage = mapping->a_ops->freepage;

- __delete_from_page_cache(page);
+ __delete_from_page_cache(page, NULL);
spin_unlock_irq(&mapping->tree_lock);
mem_cgroup_uncharge_cache_page(page);

--
1.8.5.3

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