[PATCH v2 10/17] locks: move i_lock acquisition into generic_*_lease handlers

Jeff Layton
2014-09-04T12:39:12Z

Now that we have a saner internal API for managing leases, we no longer
need to mandate that the inode->i_lock be held over most of the lease
code. Push it down into generic_add_lease and generic_delete_lease.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
fs/locks.c | 21 +++++++++------------
1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/fs/locks.c b/fs/locks.c
index a5ed4a1f73ca..5bc61091263f 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1330,6 +1330,8 @@ static void time_out_leases(struct inode *inode)
struct file_lock **before;
struct file_lock *fl;

+ lockdep_assert_held(&inode->i_lock);
+
before = &inode->i_flock;
while ((fl = *before) && IS_LEASE(fl) && lease_breaking(fl)) {
trace_time_out_leases(inode, fl);
@@ -1590,6 +1592,8 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr
return -EINVAL;
}

+ spin_lock(&inode->i_lock);
+ time_out_leases(inode);
error = check_conflicting_open(dentry, arg);
if (error)
goto out;
@@ -1655,6 +1659,7 @@ out_setup:
if (lease->fl_lmops->lm_setup)
lease->fl_lmops->lm_setup(lease, priv);
out:
+ spin_unlock(&inode->i_lock);
if (is_deleg)
mutex_unlock(&inode->i_mutex);
if (!error && !my_before)
@@ -1672,6 +1677,7 @@ static int generic_delete_lease(struct file *filp)
struct dentry *dentry = filp->f_path.dentry;
struct inode *inode = dentry->d_inode;

+ spin_lock(&inode->i_lock);
for (before = &inode->i_flock;
((fl = *before) != NULL) && IS_LEASE(fl);
before = &fl->fl_next) {
@@ -1681,6 +1687,7 @@ static int generic_delete_lease(struct file *filp)
trace_generic_delete_lease(inode, fl);
if (fl)
error = fl->fl_lmops->lm_change(before, F_UNLCK);
+ spin_unlock(&inode->i_lock);
return error;
}

@@ -1694,8 +1701,6 @@ static int generic_delete_lease(struct file *filp)
*
* The (input) flp->fl_lmops->lm_break function is required
* by break_lease().
- *
- * Called with inode->i_lock held.
*/
int generic_setlease(struct file *filp, long arg, struct file_lock **flp,
void **priv)
@@ -1712,8 +1717,6 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp,
if (error)
return error;

- time_out_leases(inode);
-
switch (arg) {
case F_UNLCK:
return generic_delete_lease(filp);
@@ -1750,16 +1753,10 @@ EXPORT_SYMBOL(generic_setlease);
int
vfs_setlease(struct file *filp, long arg, struct file_lock **lease, void **priv)
{
- struct inode *inode = file_inode(filp);
- int error;
-
- spin_lock(&inode->i_lock);
if (filp->f_op->setlease)
- error = filp->f_op->setlease(filp, arg, lease, priv);
+ return filp->f_op->setlease(filp, arg, lease, priv);
else
- error = generic_setlease(filp, arg, lease, priv);
- spin_unlock(&inode->i_lock);
- return error;
+ return generic_setlease(filp, arg, lease, priv);
}
EXPORT_SYMBOL_GPL(vfs_setlease);

--
1.9.3