1 // SPDX-License-Identifier: GPL-2.0-or-later
13 /* Simple VFS hooks based on: */
28 #include <linux/init.h>
30 #include <linux/backing-dev.h>
31 #include <linux/poll.h>
58  * via standard usage.  For example, Linux's default poll always returns
59  * EPOLLIN, so there is no way for a caller of poll(2) to know when dlmfs
60  * added poll support.  Instead, we provide this list of new capabilities.
62  * Capabilities is a read-only attribute.  We do it as a module parameter
67  * distinct from the locking protocol, which is concerned with inter-node
71  * - bast	: EPOLLIN against the file descriptor of a held lock
72  *		  signifies a bast fired on the lock.
78 	printk(KERN_ERR "%s: readonly parameter\n", kp->name);  in param_set_dlmfs_capabilities()
79 	return -EINVAL;  in param_set_dlmfs_capabilities()
95  * O_RDONLY -> PRMODE level
96  * O_WRONLY -> EXMODE level
98  * O_NONBLOCK -> NOQUEUE
123 	if (S_ISDIR(inode->i_mode))  in dlmfs_file_open()
126 	mlog(0, "open called on inode %lu, flags 0x%x\n", inode->i_ino,  in dlmfs_file_open()
127 		file->f_flags);  in dlmfs_file_open()
129 	status = dlmfs_decode_open_flags(file->f_flags, &level, &flags);  in dlmfs_file_open()
135 	file->f_flags &= ~O_APPEND;  in dlmfs_file_open()
139 		status = -ENOMEM;  in dlmfs_file_open()
142 	fp->fp_lock_level = level;  in dlmfs_file_open()
146 	status = user_dlm_cluster_lock(&ip->ip_lockres, level, flags);  in dlmfs_file_open()
152 		if (flags & DLM_LKF_NOQUEUE && status == -EAGAIN)  in dlmfs_file_open()
153 			status = -ETXTBSY;  in dlmfs_file_open()
158 	file->private_data = fp;  in dlmfs_file_open()
168 	struct dlmfs_filp_private *fp = file->private_data;  in dlmfs_file_release()
170 	if (S_ISDIR(inode->i_mode))  in dlmfs_file_release()
173 	mlog(0, "close called on inode %lu\n", inode->i_ino);  in dlmfs_file_release()
176 		level = fp->fp_lock_level;  in dlmfs_file_release()
178 			user_dlm_cluster_unlock(&ip->ip_lockres, level);  in dlmfs_file_release()
181 		file->private_data = NULL;  in dlmfs_file_release()
188  * We do ->setattr() just to override size changes.  Our size is the size
197 	attr->ia_valid &= ~ATTR_SIZE;  in dlmfs_file_setattr()
213 	poll_wait(file, &ip->ip_lockres.l_event, wait);  in dlmfs_file_poll()
215 	spin_lock(&ip->ip_lockres.l_lock);  in dlmfs_file_poll()
216 	if (ip->ip_lockres.l_flags & USER_LOCK_BLOCKED)  in dlmfs_file_poll()
218 	spin_unlock(&ip->ip_lockres.l_lock);  in dlmfs_file_poll()
246 		inode->i_ino, count, *ppos);  in dlmfs_file_write()
249 		return -ENOSPC;  in dlmfs_file_write()
252 	if (count > DLM_LVB_LEN - *ppos)  in dlmfs_file_write()
253 		count = DLM_LVB_LEN - *ppos;  in dlmfs_file_write()
259 	count -= bytes_left;  in dlmfs_file_write()
273 	ip->ip_conn = NULL;  in dlmfs_init_once()
274 	ip->ip_parent = NULL;  in dlmfs_init_once()
276 	inode_init_once(&ip->ip_vfs_inode);  in dlmfs_init_once()
287 	return &ip->ip_vfs_inode;  in dlmfs_alloc_inode()
304 	mlog(0, "inode %lu\n", inode->i_ino);  in dlmfs_evict_inode()
307 	lockres = &ip->ip_lockres;  in dlmfs_evict_inode()
309 	if (S_ISREG(inode->i_mode)) {  in dlmfs_evict_inode()
310 		spin_lock(&lockres->l_lock);  in dlmfs_evict_inode()
311 		teardown = !!(lockres->l_flags & USER_LOCK_IN_TEARDOWN);  in dlmfs_evict_inode()
312 		spin_unlock(&lockres->l_lock);  in dlmfs_evict_inode()
318 		iput(ip->ip_parent);  in dlmfs_evict_inode()
322 	mlog(0, "we're a directory, ip->ip_conn = 0x%p\n", ip->ip_conn);  in dlmfs_evict_inode()
325 	if (ip->ip_conn)  in dlmfs_evict_inode()
326 		user_dlm_unregister(ip->ip_conn);  in dlmfs_evict_inode()
328 	ip->ip_parent = NULL;  in dlmfs_evict_inode()
329 	ip->ip_conn = NULL;  in dlmfs_evict_inode()
338 		inode->i_ino = get_next_ino();  in dlmfs_get_root_inode()
343 		inode->i_fop = &simple_dir_operations;  in dlmfs_get_root_inode()
344 		inode->i_op = &dlmfs_root_inode_operations;  in dlmfs_get_root_inode()
354 	struct super_block *sb = parent->i_sb;  in dlmfs_get_inode()
361 	inode->i_ino = get_next_ino();  in dlmfs_get_inode()
366 	ip->ip_conn = DLMFS_I(parent)->ip_conn;  in dlmfs_get_inode()
375 		inode->i_op = &dlmfs_file_inode_operations;  in dlmfs_get_inode()
376 		inode->i_fop = &dlmfs_file_operations;  in dlmfs_get_inode()
380 		user_dlm_lock_res_init(&ip->ip_lockres, dentry);  in dlmfs_get_inode()
383 		 * get to drop the dlm reference on each lock *before*  in dlmfs_get_inode()
386 		ip->ip_parent = igrab(parent);  in dlmfs_get_inode()
387 		BUG_ON(!ip->ip_parent);  in dlmfs_get_inode()
390 		inode->i_op = &dlmfs_dir_inode_operations;  in dlmfs_get_inode()
391 		inode->i_fop = &simple_dir_operations;  in dlmfs_get_inode()
404 /* SMP-safe */
412 	const struct qstr *domain = &dentry->d_name;  in dlmfs_mkdir()
416 	mlog(0, "mkdir %.*s\n", domain->len, domain->name);  in dlmfs_mkdir()
419 	if (domain->len >= GROUP_NAME_MAX) {  in dlmfs_mkdir()
420 		status = -EINVAL;  in dlmfs_mkdir()
427 		status = -ENOMEM;  in dlmfs_mkdir()
438 		     status, domain->len, domain->name);  in dlmfs_mkdir()
441 	ip->ip_conn = conn;  in dlmfs_mkdir()
445 	dget(dentry);	/* Extra count - pin the dentry in core */  in dlmfs_mkdir()
462 	const struct qstr *name = &dentry->d_name;  in dlmfs_create()
464 	mlog(0, "create %.*s\n", name->len, name->name);  in dlmfs_create()
468 	if (name->len >= USER_DLM_LOCK_ID_MAX_LEN ||  in dlmfs_create()
469 	    name->name[0] == '$') {  in dlmfs_create()
470 		status = -EINVAL;  in dlmfs_create()
471 		mlog(ML_ERROR, "invalid lock name, %.*s\n", name->len,  in dlmfs_create()
472 		     name->name);  in dlmfs_create()
478 		status = -ENOMEM;  in dlmfs_create()
484 	dget(dentry);	/* Extra count - pin the dentry in core */  in dlmfs_create()
495 	mlog(0, "unlink inode %lu\n", inode->i_ino);  in dlmfs_unlink()
497 	/* if there are no current holders, or none that are waiting  in dlmfs_unlink()
499 	status = user_dlm_destroy_lock(&DLMFS_I(inode)->ip_lockres);  in dlmfs_unlink()
512 	sb->s_maxbytes = MAX_LFS_FILESIZE;  in dlmfs_fill_super()
513 	sb->s_blocksize = PAGE_SIZE;  in dlmfs_fill_super()
514 	sb->s_blocksize_bits = PAGE_SHIFT;  in dlmfs_fill_super()
515 	sb->s_magic = DLMFS_MAGIC;  in dlmfs_fill_super()
516 	sb->s_op = &dlmfs_ops;  in dlmfs_fill_super()
517 	sb->s_root = d_make_root(dlmfs_get_root_inode(sb));  in dlmfs_fill_super()
518 	if (!sb->s_root)  in dlmfs_fill_super()
519 		return -ENOMEM;  in dlmfs_fill_super()
526 	.poll		= dlmfs_file_poll,
569 	fc->ops = &dlmfs_context_ops;  in dlmfs_init_fs_context()
593 		status = -ENOMEM;  in init_dlmfs_fs()
601 		status = -ENOMEM;  in init_dlmfs_fs()
636 MODULE_DESCRIPTION("OCFS2 DLM-Filesystem");