[PATCH v2 13/17] locks: remove i_have_this_lease check from __break_lease

Jeff Layton
2014-09-04T12:39:17Z

I think that the intent of this code was to ensure that a process won't
deadlock if it has one fd open with a lease on it and then breaks that
lease by opening another fd. In that case it'll treat the __break_lease
call as if it were non-blocking.

This seems wrong -- the process could (for instance) be multithreaded
and managing different fds via different threads. I also don't see any
mention of this limitation in the (somewhat sketchy) documentation.

Remove the check and the non-blocking behavior when i_have_this_lease
is true.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
---
fs/locks.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/fs/locks.c b/fs/locks.c
index dc2e9e18f32d..011812490c92 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1370,7 +1370,6 @@ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
struct file_lock *new_fl, *flock;
struct file_lock *fl;
unsigned long break_time;
- int i_have_this_lease = 0;
bool lease_conflict = false;
int want_write = (mode & O_ACCMODE) != O_RDONLY;
LIST_HEAD(dispose);
@@ -1391,8 +1390,7 @@ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
for (fl = flock; fl && IS_LEASE(fl); fl = fl->fl_next) {
if (leases_conflict(fl, new_fl)) {
lease_conflict = true;
- if (fl->fl_owner == current->files)
- i_have_this_lease = 1;
+ break;
}
}
if (!lease_conflict)
@@ -1422,7 +1420,7 @@ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
fl->fl_lmops->lm_break(fl);
}

- if (i_have_this_lease || (mode & O_NONBLOCK)) {
+ if (mode & O_NONBLOCK) {
trace_break_lease_noblock(inode, new_fl);
error = -EWOULDBLOCK;
goto out;
--
1.9.3