From e6f5c78930e409f3a6b37f5484313a416359ac7f Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@primarydata.com>
Date: Fri, 22 Aug 2014 10:40:25 -0400
Subject: locks: plumb a "priv" pointer into the setlease routines
In later patches, we're going to add a new lock_manager_operation to
finish setting up the lease while still holding the i_lock. To do
this, we'll need to pass a little bit of info in the fcntl setlease
case (primarily an fasync structure). Plumb the extra pointer into
there in advance of that.
We declare this pointer as a void ** to make it clear that this is
private info, and that the caller isn't required to set this unless
the lm_setup specifically requires it.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
Documentation/filesystems/Locking | 2 +-
Documentation/filesystems/vfs.txt | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
(limited to 'Documentation')
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index f1997e9da61f..3d92049ae71d 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -464,7 +464,7 @@ prototypes:
size_t, unsigned int);
ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *,
size_t, unsigned int);
- int (*setlease)(struct file *, long, struct file_lock **);
+ int (*setlease)(struct file *, long, struct file_lock **, void **);
long (*fallocate)(struct file *, int, loff_t, loff_t);
};
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index 61d65cc65c54..28ebd49f169f 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -826,7 +826,7 @@ struct file_operations {
int (*flock) (struct file *, int, struct file_lock *);
ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, size_t, unsigned int);
ssize_t (*splice_read)(struct file *, struct pipe_inode_info *, size_t, unsigned int);
- int (*setlease)(struct file *, long arg, struct file_lock **);
+ int (*setlease)(struct file *, long arg, struct file_lock **, void **);
long (*fallocate)(struct file *, int mode, loff_t offset, loff_t len);
int (*show_fdinfo)(struct seq_file *m, struct file *f);
};
--
cgit v1.2.3
From f82b4b6780afabce9d9a91c84fae17ec3d63b9d7 Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@primarydata.com>
Date: Fri, 22 Aug 2014 18:50:48 -0400
Subject: locks: move i_lock acquisition into generic_*_lease handlers
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>
---
Documentation/filesystems/Locking | 6 ++++--
Documentation/filesystems/vfs.txt | 5 +++--
fs/locks.c | 21 +++++++++------------
3 files changed, 16 insertions(+), 16 deletions(-)
(limited to 'Documentation')
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 3d92049ae71d..4af288e38f13 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -472,8 +472,6 @@ locking rules:
All may block except for ->setlease.
No VFS locks held on entry except for ->setlease.
-->setlease has the file_list_lock held and must not sleep.
-
->llseek() locking has moved from llseek to the individual llseek
implementations. If your fs is not using generic_file_llseek, you
need to acquire and release the appropriate locks in your ->llseek().
@@ -496,6 +494,10 @@ components. And there are other reasons why the current interface is a mess...
->read on directories probably must go away - we should just enforce -EISDIR
in sys_read() and friends.
+->setlease operations should call generic_setlease() before or after setting
+the lease within the individual filesystem to record the result of the
+operation
+
--------------------------- dquot_operations -------------------------------
prototypes:
int (*write_dquot) (struct dquot *);
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index 28ebd49f169f..8be1ea3bdd5a 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -895,8 +895,9 @@ otherwise noted.
splice_read: called by the VFS to splice data from file to a pipe. This
method is used by the splice(2) system call
- setlease: called by the VFS to set or release a file lock lease.
- setlease has the file_lock_lock held and must not sleep.
+ setlease: called by the VFS to set or release a file lock lease. setlease
+ implementations should call generic_setlease to record or remove
+ the lease in the inode after setting it.
fallocate: called by the VFS to preallocate blocks or punch a hole.
diff --git a/fs/locks.c b/fs/locks.c
index a237ba632e8d..eb463257f867 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);
--
cgit v1.2.3
From c45198eda2794bb72601c9f96266d8b95db66dd5 Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@primarydata.com>
Date: Mon, 1 Sep 2014 07:12:07 -0400
Subject: locks: move freeing of leases outside of i_lock
There was only one place where we still could free a file_lock while
holding the i_lock -- lease_modify. Add a new list_head argument to the
lm_change operation, pass in a private list when calling it, and fix
those callers to dispose of the list once the lock has been dropped.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
Documentation/filesystems/Locking | 3 +--
fs/locks.c | 34 ++++++++++++++++++++++------------
fs/nfsd/nfs4state.c | 6 +++---
include/linux/fs.h | 7 ++++---
4 files changed, 30 insertions(+), 20 deletions(-)
(limited to 'Documentation')
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 4af288e38f13..94d93b1f8b53 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -469,8 +469,7 @@ prototypes:
};
locking rules:
- All may block except for ->setlease.
- No VFS locks held on entry except for ->setlease.
+ All may block.
->llseek() locking has moved from llseek to the individual llseek
implementations. If your fs is not using generic_file_llseek, you
diff --git a/fs/locks.c b/fs/locks.c
index eb463257f867..c0f789dfa655 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1292,7 +1292,7 @@ static void lease_clear_pending(struct file_lock *fl, int arg)
}
/* We already had a lease on this file; just change its type */
-int lease_modify(struct file_lock **before, int arg)
+int lease_modify(struct file_lock **before, int arg, struct list_head *dispose)
{
struct file_lock *fl = *before;
int error = assign_type(fl, arg);
@@ -1311,7 +1311,7 @@ int lease_modify(struct file_lock **before, int arg)
printk(KERN_ERR "locks_delete_lock: fasync == %p\n", fl->fl_fasync);
fl->fl_fasync = NULL;
}
- locks_delete_lock(before, NULL);
+ locks_delete_lock(before, dispose);
}
return 0;
}
@@ -1325,7 +1325,7 @@ static bool past_time(unsigned long then)
return time_after(jiffies, then);
}
-static void time_out_leases(struct inode *inode)
+static void time_out_leases(struct inode *inode, struct list_head *dispose)
{
struct file_lock **before;
struct file_lock *fl;
@@ -1336,9 +1336,9 @@ static void time_out_leases(struct inode *inode)
while ((fl = *before) && IS_LEASE(fl) && lease_breaking(fl)) {
trace_time_out_leases(inode, fl);
if (past_time(fl->fl_downgrade_time))
- lease_modify(before, F_RDLCK);
+ lease_modify(before, F_RDLCK, dispose);
if (past_time(fl->fl_break_time))
- lease_modify(before, F_UNLCK);
+ lease_modify(before, F_UNLCK, dispose);
if (fl == *before) /* lease_modify may have freed fl */
before = &fl->fl_next;
}
@@ -1373,6 +1373,7 @@ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
int i_have_this_lease = 0;
bool lease_conflict = false;
int want_write = (mode & O_ACCMODE) != O_RDONLY;
+ LIST_HEAD(dispose);
new_fl = lease_alloc(NULL, want_write ? F_WRLCK : F_RDLCK);
if (IS_ERR(new_fl))
@@ -1381,7 +1382,7 @@ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
spin_lock(&inode->i_lock);
- time_out_leases(inode);
+ time_out_leases(inode, &dispose);
flock = inode->i_flock;
if ((flock == NULL) || !IS_LEASE(flock))
@@ -1436,6 +1437,7 @@ restart:
locks_insert_block(flock, new_fl);
trace_break_lease_block(inode, new_fl);
spin_unlock(&inode->i_lock);
+ locks_dispose_list(&dispose);
error = wait_event_interruptible_timeout(new_fl->fl_wait,
!new_fl->fl_next, break_time);
spin_lock(&inode->i_lock);
@@ -1443,7 +1445,7 @@ restart:
locks_delete_block(new_fl);
if (error >= 0) {
if (error == 0)
- time_out_leases(inode);
+ time_out_leases(inode, &dispose);
/*
* Wait for the next conflicting lease that has not been
* broken yet
@@ -1458,6 +1460,7 @@ restart:
out:
spin_unlock(&inode->i_lock);
+ locks_dispose_list(&dispose);
locks_free_lock(new_fl);
return error;
}
@@ -1522,9 +1525,10 @@ int fcntl_getlease(struct file *filp)
struct file_lock *fl;
struct inode *inode = file_inode(filp);
int type = F_UNLCK;
+ LIST_HEAD(dispose);
spin_lock(&inode->i_lock);
- time_out_leases(file_inode(filp));
+ time_out_leases(file_inode(filp), &dispose);
for (fl = file_inode(filp)->i_flock; fl && IS_LEASE(fl);
fl = fl->fl_next) {
if (fl->fl_file == filp) {
@@ -1533,6 +1537,7 @@ int fcntl_getlease(struct file *filp)
}
}
spin_unlock(&inode->i_lock);
+ locks_dispose_list(&dispose);
return type;
}
@@ -1570,6 +1575,7 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr
struct inode *inode = dentry->d_inode;
bool is_deleg = (*flp)->fl_flags & FL_DELEG;
int error;
+ LIST_HEAD(dispose);
lease = *flp;
trace_generic_add_lease(inode, lease);
@@ -1593,7 +1599,7 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr
}
spin_lock(&inode->i_lock);
- time_out_leases(inode);
+ time_out_leases(inode, &dispose);
error = check_conflicting_open(dentry, arg);
if (error)
goto out;
@@ -1630,7 +1636,7 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr
if (my_before != NULL) {
lease = *my_before;
- error = lease->fl_lmops->lm_change(my_before, arg);
+ error = lease->fl_lmops->lm_change(my_before, arg, &dispose);
if (error)
goto out;
goto out_setup;
@@ -1660,6 +1666,7 @@ out_setup:
lease->fl_lmops->lm_setup(lease, priv);
out:
spin_unlock(&inode->i_lock);
+ locks_dispose_list(&dispose);
if (is_deleg)
mutex_unlock(&inode->i_mutex);
if (!error && !my_before)
@@ -1676,8 +1683,10 @@ static int generic_delete_lease(struct file *filp)
struct file_lock *fl, **before;
struct dentry *dentry = filp->f_path.dentry;
struct inode *inode = dentry->d_inode;
+ LIST_HEAD(dispose);
spin_lock(&inode->i_lock);
+ time_out_leases(inode, &dispose);
for (before = &inode->i_flock;
((fl = *before) != NULL) && IS_LEASE(fl);
before = &fl->fl_next) {
@@ -1686,8 +1695,9 @@ 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);
+ error = fl->fl_lmops->lm_change(before, F_UNLCK, &dispose);
spin_unlock(&inode->i_lock);
+ locks_dispose_list(&dispose);
return error;
}
@@ -2372,7 +2382,7 @@ void locks_remove_file(struct file *filp)
while ((fl = *before) != NULL) {
if (fl->fl_file == filp) {
if (IS_LEASE(fl)) {
- lease_modify(before, F_UNLCK);
+ lease_modify(before, F_UNLCK, &dispose);
continue;
}
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 5349528136e2..604ab6decd28 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3427,11 +3427,11 @@ static void nfsd_break_deleg_cb(struct file_lock *fl)
spin_unlock(&fp->fi_lock);
}
-static
-int nfsd_change_deleg_cb(struct file_lock **onlist, int arg)
+static int
+nfsd_change_deleg_cb(struct file_lock **onlist, int arg, struct list_head *dispose)
{
if (arg & F_UNLCK)
- return lease_modify(onlist, arg);
+ return lease_modify(onlist, arg, dispose);
else
return -EAGAIN;
}
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 9a6d56154dd5..f419f718e447 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -873,7 +873,7 @@ struct lock_manager_operations {
void (*lm_notify)(struct file_lock *); /* unblock callback */
int (*lm_grant)(struct file_lock *, int);
void (*lm_break)(struct file_lock *);
- int (*lm_change)(struct file_lock **, int);
+ int (*lm_change)(struct file_lock **, int, struct list_head *);
void (*lm_setup)(struct file_lock *, void **);
};
@@ -985,7 +985,7 @@ extern int __break_lease(struct inode *inode, unsigned int flags, unsigned int t
extern void lease_get_mtime(struct inode *, struct timespec *time);
extern int generic_setlease(struct file *, long, struct file_lock **, void **priv);
extern int vfs_setlease(struct file *, long, struct file_lock **, void **);
-extern int lease_modify(struct file_lock **, int);
+extern int lease_modify(struct file_lock **, int, struct list_head *);
#else /* !CONFIG_FILE_LOCKING */
static inline int fcntl_getlk(struct file *file, unsigned int cmd,
struct flock __user *user)
@@ -1112,7 +1112,8 @@ static inline int vfs_setlease(struct file *filp, long arg,
return -EINVAL;
}
-static inline int lease_modify(struct file_lock **before, int arg)
+static inline int lease_modify(struct file_lock **before, int arg,
+ struct list_head *dispose)
{
return -EINVAL;
}
--
cgit v1.2.3