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>

7 files changed, 37 insertions, 26 deletions

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);
 };
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index ac4f260155c8..85c70d5969ac 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -800,7 +800,8 @@ static loff_t cifs_llseek(struct file *file, loff_t offset, int whence)
         return generic_file_llseek(file, offset, whence);
 }
 
-static int cifs_setlease(struct file *file, long arg, struct file_lock **lease)
+static int
+cifs_setlease(struct file *file, long arg, struct file_lock **lease, void **priv)
 {
         /*
          * Note that this is called by vfs setlease with i_lock held to
@@ -815,7 +816,7 @@ static int cifs_setlease(struct file *file, long arg, struct file_lock **lease)
         /* check if file is oplocked */
         if (((arg == F_RDLCK) && CIFS_CACHE_READ(CIFS_I(inode))) ||
             ((arg == F_WRLCK) && CIFS_CACHE_WRITE(CIFS_I(inode))))
-                return generic_setlease(file, arg, lease);
+                return generic_setlease(file, arg, lease, priv);
         else if (tlink_tcon(cfile->tlink)->local_lease &&
                  !CIFS_CACHE_READ(CIFS_I(inode)))
                 /*
@@ -826,7 +827,7 @@ static int cifs_setlease(struct file *file, long arg, struct file_lock **lease)
                  * knows that the file won't be changed on the server by anyone
                  * else.
                  */
-                return generic_setlease(file, arg, lease);
+                return generic_setlease(file, arg, lease, priv);
         else
                 return -EAGAIN;
 }
diff --git a/fs/libfs.c b/fs/libfs.c
index 29012a303ef8..171d2846f2a3 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -1081,12 +1081,14 @@ EXPORT_SYMBOL(alloc_anon_inode);
  * @filp: file pointer
  * @arg: type of lease to obtain
  * @flp: new lease supplied for insertion
+ * @priv: private data for lm_setup operation
  *
  * Generic helper for filesystems that do not wish to allow leases to be set.
  * All arguments are ignored and it just returns -EINVAL.
  */
 int
-simple_nosetlease(struct file *filp, long arg, struct file_lock **flp)
+simple_nosetlease(struct file *filp, long arg, struct file_lock **flp,
+                  void **priv)
 {
         return -EINVAL;
 }
diff --git a/fs/locks.c b/fs/locks.c
index e16c2c61a44f..4fa269b0bdef 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1297,7 +1297,6 @@ int lease_modify(struct file_lock **before, int arg)
         }
         return 0;
 }
-
 EXPORT_SYMBOL(lease_modify);
 
 static bool past_time(unsigned long then)
@@ -1543,7 +1542,8 @@ check_conflicting_open(const struct dentry *dentry, const long arg)
         return ret;
 }
 
-static int generic_add_lease(struct file *filp, long arg, struct file_lock **flp)
+static int
+generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **priv)
 {
         struct file_lock *fl, **before, **my_before = NULL, *lease;
         struct dentry *dentry = filp->f_path.dentry;
@@ -1630,11 +1630,14 @@ static int generic_add_lease(struct file *filp, long arg, struct file_lock **flp
         smp_mb();
         error = check_conflicting_open(dentry, arg);
         if (error)
-                locks_unlink_lock(before);
+                goto out_unlink;
 out:
         if (is_deleg)
                 mutex_unlock(&inode->i_mutex);
         return error;
+out_unlink:
+        locks_unlink_lock(before);
+        goto out;
 }
 
 static int generic_delete_lease(struct file *filp)
@@ -1661,13 +1664,15 @@ static int generic_delete_lease(struct file *filp)
  *      @filp: file pointer
  *      @arg: type of lease to obtain
  *      @flp: input - file_lock to use, output - file_lock inserted
+ *      @priv: private data for lm_setup
  *
  *      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)
+int generic_setlease(struct file *filp, long arg, struct file_lock **flp,
+                        void **priv)
 {
         struct dentry *dentry = filp->f_path.dentry;
         struct inode *inode = dentry->d_inode;
@@ -1692,19 +1697,20 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
                         WARN_ON_ONCE(1);
                         return -ENOLCK;
                 }
-                return generic_add_lease(filp, arg, flp);
+                return generic_add_lease(filp, arg, flp, priv);
         default:
                 return -EINVAL;
         }
 }
 EXPORT_SYMBOL(generic_setlease);
 
-static int __vfs_setlease(struct file *filp, long arg, struct file_lock **lease)
+static int
+__vfs_setlease(struct file *filp, long arg, struct file_lock **lease, void **priv)
 {
         if (filp->f_op->setlease)
-                return filp->f_op->setlease(filp, arg, lease);
+                return filp->f_op->setlease(filp, arg, lease, priv);
         else
-                return generic_setlease(filp, arg, lease);
+                return generic_setlease(filp, arg, lease, priv);
 }
 
 /**
@@ -1712,6 +1718,7 @@ static int __vfs_setlease(struct file *filp, long arg, struct file_lock **lease)
  * @filp: file pointer
  * @arg: type of lease to obtain
  * @lease: file_lock to use when adding a lease
+ * @priv: private info for lm_setup when adding a lease
  *
  * Call this to establish a lease on the file. The "lease" argument is not
  * used for F_UNLCK requests and may be NULL. For commands that set or alter
@@ -1720,13 +1727,14 @@ static int __vfs_setlease(struct file *filp, long arg, struct file_lock **lease)
  * stack trace).
  */
 
-int vfs_setlease(struct file *filp, long arg, struct file_lock **lease)
+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);
-        error = __vfs_setlease(filp, arg, lease);
+        error = __vfs_setlease(filp, arg, lease, priv);
         spin_unlock(&inode->i_lock);
 
         return error;
@@ -1751,7 +1759,7 @@ static int do_fcntl_add_lease(unsigned int fd, struct file *filp, long arg)
         }
         ret = fl;
         spin_lock(&inode->i_lock);
-        error = __vfs_setlease(filp, arg, &ret);
+        error = __vfs_setlease(filp, arg, &ret, NULL);
         if (error)
                 goto out_unlock;
         if (ret == fl)
@@ -1789,7 +1797,7 @@ out_unlock:
 int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
 {
         if (arg == F_UNLCK)
-                return vfs_setlease(filp, F_UNLCK, NULL);
+                return vfs_setlease(filp, F_UNLCK, NULL, NULL);
         return do_fcntl_add_lease(fd, filp, arg);
 }
 
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 188cd68aefb6..7c803db2a027 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -686,7 +686,7 @@ static void nfs4_put_deleg_lease(struct nfs4_file *fp)
         spin_unlock(&fp->fi_lock);
 
         if (filp) {
-                vfs_setlease(filp, F_UNLCK, NULL);
+                vfs_setlease(filp, F_UNLCK, NULL, NULL);
                 fput(filp);
         }
 }
@@ -3792,7 +3792,7 @@ static int nfs4_setlease(struct nfs4_delegation *dp)
         }
         fl->fl_file = filp;
         ret = fl;
-        status = vfs_setlease(filp, fl->fl_type, &ret);
+        status = vfs_setlease(filp, fl->fl_type, &fl, NULL);
         if (status) {
                 locks_free_lock(fl);
                 goto out_fput;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 96528f73dda4..f1870eb67b02 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -982,8 +982,8 @@ extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
 extern int __break_lease(struct inode *inode, unsigned int flags, unsigned int type);
 extern void lease_get_mtime(struct inode *, struct timespec *time);
-extern int generic_setlease(struct file *, long, struct file_lock **);
-extern int vfs_setlease(struct file *, long, struct file_lock **);
+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);
 #else /* !CONFIG_FILE_LOCKING */
 static inline int fcntl_getlk(struct file *file, unsigned int cmd,
@@ -1100,13 +1100,13 @@ static inline void lease_get_mtime(struct inode *inode, struct timespec *time)
 }
 
 static inline int generic_setlease(struct file *filp, long arg,
-                                    struct file_lock **flp)
+                                    struct file_lock **flp, void **priv)
 {
         return -EINVAL;
 }
 
 static inline int vfs_setlease(struct file *filp, long arg,
-                               struct file_lock **lease)
+                               struct file_lock **lease, void **priv)
 {
         return -EINVAL;
 }
@@ -1494,7 +1494,7 @@ struct file_operations {
         int (*flock) (struct file *, int, struct file_lock *);
         ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, 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 *file, int mode, loff_t offset,
                           loff_t len);
         int (*show_fdinfo)(struct seq_file *m, struct file *f);
@@ -2599,7 +2599,7 @@ extern int simple_write_end(struct file *file, struct address_space *mapping,
                         struct page *page, void *fsdata);
 extern int always_delete_dentry(const struct dentry *);
 extern struct inode *alloc_anon_inode(struct super_block *);
-extern int simple_nosetlease(struct file *, long, struct file_lock **);
+extern int simple_nosetlease(struct file *, long, struct file_lock **, void **);
 extern const struct dentry_operations simple_dentry_operations;
 
 extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags);