From: Trond Myklebust VFS: Enable filesystems and to hook certain functions for copying locks, and freeing locks using the new struct file_lock_operations. VFS: Enable lock managers (i.e. lockd) to hook functions for comparing lock ownership using the new struct lock_manager_operations. Signed-off-by: Trond Myklebust Signed-off-by: Andrew Morton --- 25-akpm/fs/locks.c | 32 ++++++++++++++++++++++++++------ 25-akpm/include/linux/fs.h | 11 +++++++++++ 2 files changed, 37 insertions(+), 6 deletions(-) diff -puN fs/locks.c~posix-locking-hook-functions fs/locks.c --- 25/fs/locks.c~posix-locking-hook-functions 2004-08-15 17:10:30.228157640 -0700 +++ 25-akpm/fs/locks.c 2004-08-15 17:10:30.235156576 -0700 @@ -167,6 +167,13 @@ static inline void locks_free_lock(struc if (!list_empty(&fl->fl_link)) panic("Attempting to free lock on active lock list"); + if (fl->fl_ops) { + if (fl->fl_ops->fl_release_private) + fl->fl_ops->fl_release_private(fl); + fl->fl_ops = NULL; + } + fl->fl_lmops = NULL; + kmem_cache_free(filelock_cache, fl); } @@ -186,6 +193,8 @@ void locks_init_lock(struct file_lock *f fl->fl_notify = NULL; fl->fl_insert = NULL; fl->fl_remove = NULL; + fl->fl_ops = NULL; + fl->fl_lmops = NULL; } EXPORT_SYMBOL(locks_init_lock); @@ -220,7 +229,10 @@ void locks_copy_lock(struct file_lock *n new->fl_notify = fl->fl_notify; new->fl_insert = fl->fl_insert; new->fl_remove = fl->fl_remove; - new->fl_u = fl->fl_u; + new->fl_ops = fl->fl_ops; + new->fl_lmops = fl->fl_lmops; + if (fl->fl_ops && fl->fl_ops->fl_copy_lock) + fl->fl_ops->fl_copy_lock(new, fl); } EXPORT_SYMBOL(locks_copy_lock); @@ -324,6 +336,8 @@ static int flock_to_posix_lock(struct fi fl->fl_notify = NULL; fl->fl_insert = NULL; fl->fl_remove = NULL; + fl->fl_ops = NULL; + fl->fl_lmops = NULL; return assign_type(fl, l->l_type); } @@ -364,6 +378,8 @@ static int flock64_to_posix_lock(struct fl->fl_notify = NULL; fl->fl_insert = NULL; fl->fl_remove = NULL; + fl->fl_ops = NULL; + fl->fl_lmops = NULL; switch (l->l_type) { case F_RDLCK: @@ -400,6 +416,8 @@ static int lease_alloc(struct file *filp fl->fl_notify = NULL; fl->fl_insert = NULL; fl->fl_remove = NULL; + fl->fl_ops = NULL; + fl->fl_lmops = NULL; *flp = fl; return 0; @@ -419,10 +437,9 @@ static inline int locks_overlap(struct f static inline int posix_same_owner(struct file_lock *fl1, struct file_lock *fl2) { - /* FIXME: Replace this sort of thing with struct file_lock_operations */ - if ((fl1->fl_type | fl2->fl_type) & FL_LOCKD) - return fl1->fl_owner == fl2->fl_owner && - fl1->fl_pid == fl2->fl_pid; + if (fl1->fl_lmops && fl1->fl_lmops->fl_compare_owner) + return fl2->fl_lmops == fl1->fl_lmops && + fl1->fl_lmops->fl_compare_owner(fl1, fl2); return fl1->fl_owner == fl2->fl_owner; } @@ -1415,7 +1432,6 @@ int fcntl_getlk(struct file *filp, struc error = -EFAULT; if (!copy_to_user(l, &flock, sizeof(flock))) error = 0; - out: return error; } @@ -1665,6 +1681,8 @@ void locks_remove_posix(struct file *fil lock.fl_owner = owner; lock.fl_pid = current->tgid; lock.fl_file = filp; + lock.fl_ops = NULL; + lock.fl_lmops = NULL; if (filp->f_op && filp->f_op->lock != NULL) { filp->f_op->lock(filp, F_SETLK, &lock); @@ -1684,6 +1702,8 @@ void locks_remove_posix(struct file *fil before = &fl->fl_next; } unlock_kernel(); + if (lock.fl_ops && lock.fl_ops->fl_release_private) + lock.fl_ops->fl_release_private(&lock); } EXPORT_SYMBOL(locks_remove_posix); diff -puN include/linux/fs.h~posix-locking-hook-functions include/linux/fs.h --- 25/include/linux/fs.h~posix-locking-hook-functions 2004-08-15 17:10:30.230157336 -0700 +++ 25-akpm/include/linux/fs.h 2004-08-15 17:10:30.237156272 -0700 @@ -628,6 +628,15 @@ extern void close_private_file(struct fi */ typedef struct files_struct *fl_owner_t; +struct file_lock_operations { + void (*fl_copy_lock)(struct file_lock *, struct file_lock *); + void (*fl_release_private)(struct file_lock *); +}; + +struct lock_manager_operations { + int (*fl_compare_owner)(struct file_lock *, struct file_lock *); +}; + /* that will die - we need it for nfs_lock_info */ #include @@ -651,6 +660,8 @@ struct file_lock { struct fasync_struct * fl_fasync; /* for lease break notifications */ unsigned long fl_break_time; /* for nonblocking lease breaks */ + struct file_lock_operations *fl_ops; /* Callbacks for filesystems */ + struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */ union { struct nfs_lock_info nfs_fl; } fl_u; _