diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-13 15:08:16 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-13 15:08:16 -0700 |
commit | d4c608115c6203efbab14befab90a6d1b61177d8 (patch) | |
tree | d063741d0f150e91320dcfb3d3950c4f0bcd7de0 /fs/notify | |
parent | 29c079caf584ad9a333c0d32292d036d1ae3205f (diff) | |
parent | 4d8e7055a4058ee191296699803c5090e14f0dff (diff) |
Merge tag 'fsnotify_for_v5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fsnotify fixes from Jan Kara:
"Two fsnotify fixes"
* tag 'fsnotify_for_v5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
fsnotify: fix unlink performance regression
fsnotify: Clarify connector assignment in fsnotify_add_mark_list()
Diffstat (limited to 'fs/notify')
-rw-r--r-- | fs/notify/fsnotify.c | 41 | ||||
-rw-r--r-- | fs/notify/mark.c | 5 |
2 files changed, 46 insertions, 0 deletions
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c index 5433e37fb0c5..8c7cbac7183c 100644 --- a/fs/notify/fsnotify.c +++ b/fs/notify/fsnotify.c @@ -108,6 +108,47 @@ void fsnotify_sb_delete(struct super_block *sb) } /* + * fsnotify_nameremove - a filename was removed from a directory + * + * This is mostly called under parent vfs inode lock so name and + * dentry->d_parent should be stable. However there are some corner cases where + * inode lock is not held. So to be on the safe side and be reselient to future + * callers and out of tree users of d_delete(), we do not assume that d_parent + * and d_name are stable and we use dget_parent() and + * take_dentry_name_snapshot() to grab stable references. + */ +void fsnotify_nameremove(struct dentry *dentry, int isdir) +{ + struct dentry *parent; + struct name_snapshot name; + __u32 mask = FS_DELETE; + + /* d_delete() of pseudo inode? (e.g. __ns_get_path() playing tricks) */ + if (IS_ROOT(dentry)) + return; + + if (isdir) + mask |= FS_ISDIR; + + parent = dget_parent(dentry); + /* Avoid unneeded take_dentry_name_snapshot() */ + if (!(d_inode(parent)->i_fsnotify_mask & FS_DELETE) && + !(dentry->d_sb->s_fsnotify_mask & FS_DELETE)) + goto out_dput; + + take_dentry_name_snapshot(&name, dentry); + + fsnotify(d_inode(parent), mask, d_inode(dentry), FSNOTIFY_EVENT_INODE, + &name.name, 0); + + release_dentry_name_snapshot(&name); + +out_dput: + dput(parent); +} +EXPORT_SYMBOL(fsnotify_nameremove); + +/* * Given an inode, first check if we care what happens to our children. Inotify * and dnotify both tell their parents about events. If we care about any event * on a child we run all of our children and set a dentry flag saying that the diff --git a/fs/notify/mark.c b/fs/notify/mark.c index 22acb0a79b53..b251105f646f 100644 --- a/fs/notify/mark.c +++ b/fs/notify/mark.c @@ -619,6 +619,11 @@ restart: /* mark should be the last entry. last is the current last entry */ hlist_add_behind_rcu(&mark->obj_list, &last->obj_list); added: + /* + * Since connector is attached to object using cmpxchg() we are + * guaranteed that connector initialization is fully visible by anyone + * seeing mark->connector set. + */ WRITE_ONCE(mark->connector, conn); out_err: spin_unlock(&conn->lock); |