X-Git-Url: http://git.cascardo.info/?a=blobdiff_plain;f=fs%2Flocks.c;h=65765cb6afedaee442c1e1ab21bf7269ce9b07c7;hb=bb8430a2c8fe2b726033017daadf73c69b0348ea;hp=4de3a2666810535d1be9d12662b0544474f619c8;hpb=426e1f5cec4821945642230218876b0e89aafab1;p=cascardo%2Flinux.git

diff --git a/fs/locks.c b/fs/locks.c
index 4de3a2666810..65765cb6afed 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -142,6 +142,7 @@ int lease_break_time = 45;
 
 static LIST_HEAD(file_lock_list);
 static LIST_HEAD(blocked_list);
+static DEFINE_SPINLOCK(file_lock_lock);
 
 /*
  * Protects the two list heads above, plus the inode->i_flock list
@@ -149,23 +150,24 @@ static LIST_HEAD(blocked_list);
  */
 void lock_flocks(void)
 {
-	lock_kernel();
+	spin_lock(&file_lock_lock);
 }
 EXPORT_SYMBOL_GPL(lock_flocks);
 
 void unlock_flocks(void)
 {
-	unlock_kernel();
+	spin_unlock(&file_lock_lock);
 }
 EXPORT_SYMBOL_GPL(unlock_flocks);
 
 static struct kmem_cache *filelock_cache __read_mostly;
 
 /* Allocate an empty lock structure. */
-static struct file_lock *locks_alloc_lock(void)
+struct file_lock *locks_alloc_lock(void)
 {
 	return kmem_cache_alloc(filelock_cache, GFP_KERNEL);
 }
+EXPORT_SYMBOL_GPL(locks_alloc_lock);
 
 void locks_release_private(struct file_lock *fl)
 {
@@ -184,7 +186,7 @@ void locks_release_private(struct file_lock *fl)
 EXPORT_SYMBOL_GPL(locks_release_private);
 
 /* Free a lock which is not in use. */
-static void locks_free_lock(struct file_lock *fl)
+void locks_free_lock(struct file_lock *fl)
 {
 	BUG_ON(waitqueue_active(&fl->fl_wait));
 	BUG_ON(!list_empty(&fl->fl_block));
@@ -193,6 +195,7 @@ static void locks_free_lock(struct file_lock *fl)
 	locks_release_private(fl);
 	kmem_cache_free(filelock_cache, fl);
 }
+EXPORT_SYMBOL(locks_free_lock);
 
 void locks_init_lock(struct file_lock *fl)
 {
@@ -232,11 +235,8 @@ static void locks_copy_private(struct file_lock *new, struct file_lock *fl)
 			fl->fl_ops->fl_copy_lock(new, fl);
 		new->fl_ops = fl->fl_ops;
 	}
-	if (fl->fl_lmops) {
-		if (fl->fl_lmops->fl_copy_lock)
-			fl->fl_lmops->fl_copy_lock(new, fl);
+	if (fl->fl_lmops)
 		new->fl_lmops = fl->fl_lmops;
-	}
 }
 
 /*
@@ -1365,31 +1365,27 @@ int fcntl_getlease(struct file *filp)
 int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
 {
 	struct file_lock *fl, **before, **my_before = NULL, *lease;
-	struct file_lock *new_fl = NULL;
 	struct dentry *dentry = filp->f_path.dentry;
 	struct inode *inode = dentry->d_inode;
 	int error, rdlease_count = 0, wrlease_count = 0;
 
+	lease = *flp;
+
+	error = -EACCES;
 	if ((current_fsuid() != inode->i_uid) && !capable(CAP_LEASE))
-		return -EACCES;
+		goto out;
+	error = -EINVAL;
 	if (!S_ISREG(inode->i_mode))
-		return -EINVAL;
+		goto out;
 	error = security_file_lock(filp, arg);
 	if (error)
-		return error;
+		goto out;
 
 	time_out_leases(inode);
 
 	BUG_ON(!(*flp)->fl_lmops->fl_break);
 
-	lease = *flp;
-
 	if (arg != F_UNLCK) {
-		error = -ENOMEM;
-		new_fl = locks_alloc_lock();
-		if (new_fl == NULL)
-			goto out;
-
 		error = -EAGAIN;
 		if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
 			goto out;
@@ -1429,12 +1425,12 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
 		goto out;
 
 	if (my_before != NULL) {
-		*flp = *my_before;
 		error = lease->fl_lmops->fl_change(my_before, arg);
+		if (!error)
+			*flp = *my_before;
 		goto out;
 	}
 
-	error = 0;
 	if (arg == F_UNLCK)
 		goto out;
 
@@ -1442,15 +1438,10 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
 	if (!leases_enable)
 		goto out;
 
-	locks_copy_lock(new_fl, lease);
-	locks_insert_lock(before, new_fl);
-
-	*flp = new_fl;
+	locks_insert_lock(before, lease);
 	return 0;
 
 out:
-	if (new_fl != NULL)
-		locks_free_lock(new_fl);
 	return error;
 }
 EXPORT_SYMBOL(generic_setlease);
@@ -1502,48 +1493,81 @@ int vfs_setlease(struct file *filp, long arg, struct file_lock **lease)
 }
 EXPORT_SYMBOL_GPL(vfs_setlease);
 
-/**
- *	fcntl_setlease	-	sets a lease on an open file
- *	@fd: open file descriptor
- *	@filp: file pointer
- *	@arg: type of lease to obtain
- *
- *	Call this fcntl to establish a lease on the file.
- *	Note that you also need to call %F_SETSIG to
- *	receive a signal when the lease is broken.
- */
-int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
+static int do_fcntl_delete_lease(struct file *filp)
 {
 	struct file_lock fl, *flp = &fl;
+
+	lease_init(filp, F_UNLCK, flp);
+
+	return vfs_setlease(filp, F_UNLCK, &flp);
+}
+
+static int do_fcntl_add_lease(unsigned int fd, struct file *filp, long arg)
+{
+	struct file_lock *fl;
+	struct fasync_struct *new;
 	struct inode *inode = filp->f_path.dentry->d_inode;
 	int error;
 
-	locks_init_lock(&fl);
-	error = lease_init(filp, arg, &fl);
-	if (error)
-		return error;
+	fl = lease_alloc(filp, arg);
+	if (IS_ERR(fl))
+		return PTR_ERR(fl);
 
+	new = fasync_alloc();
+	if (!new) {
+		locks_free_lock(fl);
+		return -ENOMEM;
+	}
 	lock_flocks();
+	error = __vfs_setlease(filp, arg, &fl);
+	if (error) {
+		unlock_flocks();
+		locks_free_lock(fl);
+		goto out_free_fasync;
+	}
 
-	error = __vfs_setlease(filp, arg, &flp);
-	if (error || arg == F_UNLCK)
-		goto out_unlock;
+	/*
+	 * fasync_insert_entry() returns the old entry if any.
+	 * If there was no old entry, then it used 'new' and
+	 * inserted it into the fasync list. Clear new so that
+	 * we don't release it here.
+	 */
+	if (!fasync_insert_entry(fd, filp, &fl->fl_fasync, new))
+		new = NULL;
 
-	error = fasync_helper(fd, filp, 1, &flp->fl_fasync);
 	if (error < 0) {
 		/* remove lease just inserted by setlease */
-		flp->fl_type = F_UNLCK | F_INPROGRESS;
-		flp->fl_break_time = jiffies - 10;
+		fl->fl_type = F_UNLCK | F_INPROGRESS;
+		fl->fl_break_time = jiffies - 10;
 		time_out_leases(inode);
-		goto out_unlock;
+	} else {
+		error = __f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
 	}
-
-	error = __f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
-out_unlock:
 	unlock_flocks();
+
+out_free_fasync:
+	if (new)
+		fasync_free(new);
 	return error;
 }
 
+/**
+ *	fcntl_setlease	-	sets a lease on an open file
+ *	@fd: open file descriptor
+ *	@filp: file pointer
+ *	@arg: type of lease to obtain
+ *
+ *	Call this fcntl to establish a lease on the file.
+ *	Note that you also need to call %F_SETSIG to
+ *	receive a signal when the lease is broken.
+ */
+int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
+{
+	if (arg == F_UNLCK)
+		return do_fcntl_delete_lease(filp);
+	return do_fcntl_add_lease(fd, filp, arg);
+}
+
 /**
  * flock_lock_file_wait - Apply a FLOCK-style lock to a file
  * @filp: The file to apply the lock to