From 4542da631ad210716d097aa803a0828f9fed5e87 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 27 Feb 2013 17:04:50 -0800 Subject: [PATCH] inotify: convert to idr_alloc() Convert to the much saner new idr interface. Note that the adhoc cyclic id allocation is buggy. If wraparound happens, the previous code with idr_get_new_above() may segfault and the converted code will trigger WARN and return -EINVAL. Even if it's fixed to wrap to zero, the code will be prone to unnecessary -ENOSPC failures after the first wraparound. We probably need to implement proper cyclic support in idr. Signed-off-by: Tejun Heo Cc: John McCutchan Cc: Robert Love Cc: Eric Paris Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/notify/inotify/inotify_user.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c index 07f7a92fe88e..e0f7c1241a6a 100644 --- a/fs/notify/inotify/inotify_user.c +++ b/fs/notify/inotify/inotify_user.c @@ -364,22 +364,20 @@ static int inotify_add_to_idr(struct idr *idr, spinlock_t *idr_lock, { int ret; - do { - if (unlikely(!idr_pre_get(idr, GFP_KERNEL))) - return -ENOMEM; + idr_preload(GFP_KERNEL); + spin_lock(idr_lock); - spin_lock(idr_lock); - ret = idr_get_new_above(idr, i_mark, *last_wd + 1, - &i_mark->wd); + ret = idr_alloc(idr, i_mark, *last_wd + 1, 0, GFP_NOWAIT); + if (ret >= 0) { /* we added the mark to the idr, take a reference */ - if (!ret) { - *last_wd = i_mark->wd; - fsnotify_get_mark(&i_mark->fsn_mark); - } - spin_unlock(idr_lock); - } while (ret == -EAGAIN); + i_mark->wd = ret; + *last_wd = i_mark->wd; + fsnotify_get_mark(&i_mark->fsn_mark); + } - return ret; + spin_unlock(idr_lock); + idr_preload_end(); + return ret < 0 ? ret : 0; } static struct inotify_inode_mark *inotify_idr_find_locked(struct fsnotify_group *group, -- 2.20.1