Re: [patch 6/9] mm + fs: store shadow entries in page cache

Minchan Kim
2014-01-13T02:18:13Z

On Fri, Jan 10, 2014 at 01:10:40PM -0500, Johannes Weiner wrote:
> 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@cmpxchg.org>

Reviewed only vm part, NOT fs part.
Reviewed-by: Minchan Kim <minchan@kernel.org>

> ---
> 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/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/sysfs/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 f0890581f7f6..fc0de703066b 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 b868c2bd58d2..79cbc9c5b744 100644
> --- a/drivers/staging/lustre/lustre/llite/llite_lib.c
> +++ b/drivers/staging/lustre/lustre/llite/llite_lib.c
> @@ -1817,7 +1817,7 @@ 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 94de6d1482e2..e6716c295a99 100644
> --- a/fs/9p/vfs_inode.c
> +++ b/fs/9p/vfs_inode.c
> @@ -444,7 +444,7 @@ 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 789bc253b5f6..2bbe60e3f0e3 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 51e3afa78354..d3e498390189 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -4471,7 +4471,7 @@ void btrfs_evict_inode(struct inode *inode)
>
> trace_btrfs_inode_evict(inode);
>
> - truncate_inode_pages(&inode->i_data, 0);
> + truncate_inode_pages_final(&inode->i_data);
> if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 ||
> btrfs_is_free_space_inode(inode)))
> goto no_delete;
> diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
> index 77fc5e181077..d795c50e67cb 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 4dcc0d81a7aa..43a5b38fc8d3 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 a52a5d23c30b..d9ff4d304b41 100644
> --- a/fs/exofs/inode.c
> +++ b/fs/exofs/inode.c
> @@ -1479,7 +1479,7 @@ 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 c260de6d7b6d..115fa58bb9ae 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 2bd85486b879..153f4bec69ef 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 e274e9c1171f..3b75e70ae2eb 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 9339cd292047..0bd44f84e79b 100644
> --- a/fs/f2fs/inode.c
> +++ b/fs/f2fs/inode.c
> @@ -246,7 +246,7 @@ void f2fs_evict_inode(struct inode *inode)
> int ilock;
>
> 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 0062da21dd8b..fe802d83abdb 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 a8ce6dab60a0..09d7fa05f136 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 e5639dec66c4..ac96a99c0e5d 100644
> --- a/fs/gfs2/super.c
> +++ b/fs/gfs2/super.c
> @@ -1525,7 +1525,7 @@ 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);
> 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 4c4d142cf890..b9436d923585 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 25437280a207..0c9f64070e0f 100644
> --- a/fs/hostfs/hostfs_kern.c
> +++ b/fs/hostfs/hostfs_kern.c
> @@ -239,7 +239,7 @@ 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 b33ba8e021cc..093864ea2358 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 fe3c0527545f..00ed6c64a579 100644
> --- a/fs/jffs2/fs.c
> +++ b/fs/jffs2/fs.c
> @@ -241,7 +241,7 @@ 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/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 4659da67e7f6..e728061edb13 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 eda8879171c4..fbc38a62cbc9 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 e26acdd1a645..f2a5c44106b6 100644
> --- a/fs/nfs/nfs4super.c
> +++ b/fs/nfs/nfs4super.c
> @@ -98,7 +98,7 @@ 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 2778b0255dc6..bd50adc1e6a7 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 f87f9bd1edff..f1c46a7f9bc5 100644
> --- a/fs/ocfs2/inode.c
> +++ b/fs/ocfs2/inode.c
> @@ -951,7 +951,7 @@ 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)
> @@ -1167,7 +1167,7 @@ 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 8eaa1ba793fc..9ca0f085dada 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/sysfs/inode.c b/fs/sysfs/inode.c
> index 963f910c8034..bd0dd8d88b50 100644
> --- a/fs/sysfs/inode.c
> +++ b/fs/sysfs/inode.c
> @@ -309,7 +309,7 @@ void sysfs_evict_inode(struct inode *inode)
> {
> struct sysfs_dirent *sd = inode->i_private;
>
> - truncate_inode_pages(&inode->i_data, 0);
> + truncate_inode_pages_final(&inode->i_data);
> clear_inode(inode);
> sysfs_put(sd);
> }
> 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 3e4aa7281e04..b9ac1f350920 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 15188cc99449..47ce25dc412d 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -1006,7 +1006,7 @@ 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 3f40547ba191..9bfa5a57b4ed 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 c09ef3ae55bc..5449e7a96adf 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -1588,6 +1588,7 @@ 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 b6854b7c58cb..f132fdf5ce0f 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 23eb3be27205..d02db5801dda 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..97606fa4c458 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, acquire
> + * the spinlock 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 eea668d9cff6..b954b31602cf 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -554,7 +554,7 @@ 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);
>
> --
> 1.8.4.2
>
> --
> To unsubscribe, send a message with 'unsubscribe linux-mm' in
> the body to majordomo@kvack.org. For more info on Linux MM,
> see: http://www.linux-mm.org/ .
> Don't email: email@kvack.org

--
Kind regards,
Minchan Kim