diff options
Diffstat (limited to 'fs/locks.c')
| -rw-r--r-- | fs/locks.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/fs/locks.c b/fs/locks.c index a65d85c1fdc..94f5d8065e3 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -1429,7 +1429,24 @@ out: * @lease: file_lock to use * * Call this to establish a lease on the file. - * The fl_lmops fl_break function is required by break_lease + * The (*lease)->fl_lmops->fl_break operation must be set; if not, + * break_lease will oops! + * + * This will call the filesystem's setlease file method, if + * defined. Note that there is no getlease method; instead, the + * filesystem setlease method should call back to setlease() to + * add a lease to the inode's lease list, where fcntl_getlease() can + * find it. Since fcntl_getlease() only reports whether the current + * task holds a lease, a cluster filesystem need only do this for + * leases held by processes on this node. + * + * There is also no break_lease method; filesystems that + * handle their own leases shoud break leases themselves from the + * filesystem's open, create, and (on truncate) setattr methods. + * + * Warning: the only current setlease methods exist only to disable + * leases in certain cases. More vfs changes may be required to + * allow a full filesystem lease implementation. */ int vfs_setlease(struct file *filp, long arg, struct file_lock **lease) @@ -1437,7 +1454,10 @@ int vfs_setlease(struct file *filp, long arg, struct file_lock **lease) int error; lock_kernel(); - error = setlease(filp, arg, lease); + if (filp->f_op && filp->f_op->setlease) + error = filp->f_op->setlease(filp, arg, lease); + else + error = setlease(filp, arg, lease); unlock_kernel(); return error; |