From aabb8fdb41128705fd1627f56fdd571e45fdbcdb Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Wed, 11 Mar 2009 13:17:36 -0700 Subject: [PATCH] fs: avoid I_NEW inodes To be on the safe side, it should be less fragile to exclude I_NEW inodes from inode list scans by default (unless there is an important reason to have them). Normally they will get excluded (eg. by zero refcount or writecount etc), however it is a bit fragile for list walkers to know exactly what parts of the inode state is set up and valid to test when in I_NEW. So along these lines, move I_NEW checks upward as well (sometimes taking I_FREEING etc checks with them too -- this shouldn't be a problem should it?) Signed-off-by: Nick Piggin Acked-by: Jan Kara Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Al Viro --- fs/dquot.c | 10 ++++++++-- fs/drop_caches.c | 2 +- fs/inode.c | 2 ++ fs/notify/inotify/inotify.c | 16 ++++++++-------- 4 files changed, 19 insertions(+), 11 deletions(-) diff --git a/fs/dquot.c b/fs/dquot.c index bca3cac4bee..cb1c3bc324d 100644 --- a/fs/dquot.c +++ b/fs/dquot.c @@ -789,12 +789,12 @@ static void add_dquot_ref(struct super_block *sb, int type) spin_lock(&inode_lock); list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { + if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) + continue; if (!atomic_read(&inode->i_writecount)) continue; if (!dqinit_needed(inode, type)) continue; - if (inode->i_state & (I_FREEING|I_WILL_FREE)) - continue; __iget(inode); spin_unlock(&inode_lock); @@ -870,6 +870,12 @@ static void remove_dquot_ref(struct super_block *sb, int type, spin_lock(&inode_lock); list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { + /* + * We have to scan also I_NEW inodes because they can already + * have quota pointer initialized. Luckily, we need to touch + * only quota pointers and these have separate locking + * (dqptr_sem). + */ if (!IS_NOQUOTA(inode)) remove_inode_dquot_ref(inode, type, tofree_head); } diff --git a/fs/drop_caches.c b/fs/drop_caches.c index 3e5637fc377..44d725f612c 100644 --- a/fs/drop_caches.c +++ b/fs/drop_caches.c @@ -18,7 +18,7 @@ static void drop_pagecache_sb(struct super_block *sb) spin_lock(&inode_lock); list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { - if (inode->i_state & (I_FREEING|I_WILL_FREE)) + if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) continue; if (inode->i_mapping->nrpages == 0) continue; diff --git a/fs/inode.c b/fs/inode.c index 826fb0b9d1c..06aa5a1fb61 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -356,6 +356,8 @@ static int invalidate_list(struct list_head *head, struct list_head *dispose) if (tmp == head) break; inode = list_entry(tmp, struct inode, i_sb_list); + if (inode->i_state & I_NEW) + continue; invalidate_inode_buffers(inode); if (!atomic_read(&inode->i_count)) { list_move(&inode->i_list, dispose); diff --git a/fs/notify/inotify/inotify.c b/fs/notify/inotify/inotify.c index 331f2e88e28..220c13f0d73 100644 --- a/fs/notify/inotify/inotify.c +++ b/fs/notify/inotify/inotify.c @@ -379,6 +379,14 @@ void inotify_unmount_inodes(struct list_head *list) struct inode *need_iput_tmp; struct list_head *watches; + /* + * We cannot __iget() an inode in state I_CLEAR, I_FREEING, + * I_WILL_FREE, or I_NEW which is fine because by that point + * the inode cannot have any associated watches. + */ + if (inode->i_state & (I_CLEAR|I_FREEING|I_WILL_FREE|I_NEW)) + continue; + /* * If i_count is zero, the inode cannot have any watches and * doing an __iget/iput with MS_ACTIVE clear would actually @@ -388,14 +396,6 @@ void inotify_unmount_inodes(struct list_head *list) if (!atomic_read(&inode->i_count)) continue; - /* - * We cannot __iget() an inode in state I_CLEAR, I_FREEING, or - * I_WILL_FREE which is fine because by that point the inode - * cannot have any associated watches. - */ - if (inode->i_state & (I_CLEAR | I_FREEING | I_WILL_FREE)) - continue; - need_iput_tmp = need_iput; need_iput = NULL; /* In case inotify_remove_watch_locked() drops a reference. */ -- 2.41.0