Commit 4542da63 authored Feb 27, 2013 by Tejun Heo Committed by Linus Torvalds Feb 27, 2013

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 <tj@kernel.org>
Cc: John McCutchan <john@johnmccutchan.com>
Cc: Robert Love <rlove@rlove.org>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 2a86b3e7

fs/notify/inotify/inotify_user.c

+11 −13

Original line number	Diff line number	Diff line
		@@ -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);
		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) {
		i_mark->wd = ret;
		*last_wd = i_mark->wd;
		fsnotify_get_mark(&i_mark->fsn_mark);
		}
		spin_unlock(idr_lock);
		} while (ret == -EAGAIN);

		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,

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