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37#include <linux/module.h>
38#include <linux/fs.h>
39#include <linux/pagemap.h>
40#include <linux/types.h>
41#include <linux/slab.h>
42#include <linux/highmem.h>
43#include <linux/init.h>
44#include <linux/string.h>
45#include <linux/backing-dev.h>
46#include <linux/poll.h>
47
48#include <asm/uaccess.h>
49
50#include "stackglue.h"
51#include "userdlm.h"
52#include "dlmfsver.h"
53
54#define MLOG_MASK_PREFIX ML_DLMFS
55#include "cluster/masklog.h"
56
57
58static const struct super_operations dlmfs_ops;
59static const struct file_operations dlmfs_file_operations;
60static const struct inode_operations dlmfs_dir_inode_operations;
61static const struct inode_operations dlmfs_root_inode_operations;
62static const struct inode_operations dlmfs_file_inode_operations;
63static struct kmem_cache *dlmfs_inode_cache;
64
65struct workqueue_struct *user_dlm_worker;
66
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89
90#define DLMFS_CAPABILITIES "bast stackglue"
91static int param_set_dlmfs_capabilities(const char *val,
92 struct kernel_param *kp)
93{
94 printk(KERN_ERR "%s: readonly parameter\n", kp->name);
95 return -EINVAL;
96}
97static int param_get_dlmfs_capabilities(char *buffer,
98 struct kernel_param *kp)
99{
100 return strlcpy(buffer, DLMFS_CAPABILITIES,
101 strlen(DLMFS_CAPABILITIES) + 1);
102}
103module_param_call(capabilities, param_set_dlmfs_capabilities,
104 param_get_dlmfs_capabilities, NULL, 0444);
105MODULE_PARM_DESC(capabilities, DLMFS_CAPABILITIES);
106
107
108
109
110
111
112
113
114
115
116
117static int dlmfs_decode_open_flags(int open_flags,
118 int *level,
119 int *flags)
120{
121 if (open_flags & (O_WRONLY|O_RDWR))
122 *level = DLM_LOCK_EX;
123 else
124 *level = DLM_LOCK_PR;
125
126 *flags = 0;
127 if (open_flags & O_NONBLOCK)
128 *flags |= DLM_LKF_NOQUEUE;
129
130 return 0;
131}
132
133static int dlmfs_file_open(struct inode *inode,
134 struct file *file)
135{
136 int status, level, flags;
137 struct dlmfs_filp_private *fp = NULL;
138 struct dlmfs_inode_private *ip;
139
140 if (S_ISDIR(inode->i_mode))
141 BUG();
142
143 mlog(0, "open called on inode %lu, flags 0x%x\n", inode->i_ino,
144 file->f_flags);
145
146 status = dlmfs_decode_open_flags(file->f_flags, &level, &flags);
147 if (status < 0)
148 goto bail;
149
150
151
152 file->f_flags &= ~O_APPEND;
153
154 fp = kmalloc(sizeof(*fp), GFP_NOFS);
155 if (!fp) {
156 status = -ENOMEM;
157 goto bail;
158 }
159 fp->fp_lock_level = level;
160
161 ip = DLMFS_I(inode);
162
163 status = user_dlm_cluster_lock(&ip->ip_lockres, level, flags);
164 if (status < 0) {
165
166
167
168
169 if (flags & DLM_LKF_NOQUEUE && status == -EAGAIN)
170 status = -ETXTBSY;
171 kfree(fp);
172 goto bail;
173 }
174
175 file->private_data = fp;
176bail:
177 return status;
178}
179
180static int dlmfs_file_release(struct inode *inode,
181 struct file *file)
182{
183 int level, status;
184 struct dlmfs_inode_private *ip = DLMFS_I(inode);
185 struct dlmfs_filp_private *fp = file->private_data;
186
187 if (S_ISDIR(inode->i_mode))
188 BUG();
189
190 mlog(0, "close called on inode %lu\n", inode->i_ino);
191
192 status = 0;
193 if (fp) {
194 level = fp->fp_lock_level;
195 if (level != DLM_LOCK_IV)
196 user_dlm_cluster_unlock(&ip->ip_lockres, level);
197
198 kfree(fp);
199 file->private_data = NULL;
200 }
201
202 return 0;
203}
204
205
206
207
208
209static int dlmfs_file_setattr(struct dentry *dentry, struct iattr *attr)
210{
211 int error;
212 struct inode *inode = dentry->d_inode;
213
214 attr->ia_valid &= ~ATTR_SIZE;
215 error = inode_change_ok(inode, attr);
216 if (error)
217 return error;
218
219 setattr_copy(inode, attr);
220 mark_inode_dirty(inode);
221 return 0;
222}
223
224static unsigned int dlmfs_file_poll(struct file *file, poll_table *wait)
225{
226 int event = 0;
227 struct inode *inode = file_inode(file);
228 struct dlmfs_inode_private *ip = DLMFS_I(inode);
229
230 poll_wait(file, &ip->ip_lockres.l_event, wait);
231
232 spin_lock(&ip->ip_lockres.l_lock);
233 if (ip->ip_lockres.l_flags & USER_LOCK_BLOCKED)
234 event = POLLIN | POLLRDNORM;
235 spin_unlock(&ip->ip_lockres.l_lock);
236
237 return event;
238}
239
240static ssize_t dlmfs_file_read(struct file *filp,
241 char __user *buf,
242 size_t count,
243 loff_t *ppos)
244{
245 int bytes_left;
246 ssize_t readlen, got;
247 char *lvb_buf;
248 struct inode *inode = file_inode(filp);
249
250 mlog(0, "inode %lu, count = %zu, *ppos = %llu\n",
251 inode->i_ino, count, *ppos);
252
253 if (*ppos >= i_size_read(inode))
254 return 0;
255
256 if (!count)
257 return 0;
258
259 if (!access_ok(VERIFY_WRITE, buf, count))
260 return -EFAULT;
261
262
263 if ((count + *ppos) > i_size_read(inode))
264 readlen = i_size_read(inode) - *ppos;
265 else
266 readlen = count;
267
268 lvb_buf = kmalloc(readlen, GFP_NOFS);
269 if (!lvb_buf)
270 return -ENOMEM;
271
272 got = user_dlm_read_lvb(inode, lvb_buf, readlen);
273 if (got) {
274 BUG_ON(got != readlen);
275 bytes_left = __copy_to_user(buf, lvb_buf, readlen);
276 readlen -= bytes_left;
277 } else
278 readlen = 0;
279
280 kfree(lvb_buf);
281
282 *ppos = *ppos + readlen;
283
284 mlog(0, "read %zd bytes\n", readlen);
285 return readlen;
286}
287
288static ssize_t dlmfs_file_write(struct file *filp,
289 const char __user *buf,
290 size_t count,
291 loff_t *ppos)
292{
293 int bytes_left;
294 ssize_t writelen;
295 char *lvb_buf;
296 struct inode *inode = file_inode(filp);
297
298 mlog(0, "inode %lu, count = %zu, *ppos = %llu\n",
299 inode->i_ino, count, *ppos);
300
301 if (*ppos >= i_size_read(inode))
302 return -ENOSPC;
303
304 if (!count)
305 return 0;
306
307 if (!access_ok(VERIFY_READ, buf, count))
308 return -EFAULT;
309
310
311 if ((count + *ppos) > i_size_read(inode))
312 writelen = i_size_read(inode) - *ppos;
313 else
314 writelen = count - *ppos;
315
316 lvb_buf = kmalloc(writelen, GFP_NOFS);
317 if (!lvb_buf)
318 return -ENOMEM;
319
320 bytes_left = copy_from_user(lvb_buf, buf, writelen);
321 writelen -= bytes_left;
322 if (writelen)
323 user_dlm_write_lvb(inode, lvb_buf, writelen);
324
325 kfree(lvb_buf);
326
327 *ppos = *ppos + writelen;
328 mlog(0, "wrote %zd bytes\n", writelen);
329 return writelen;
330}
331
332static void dlmfs_init_once(void *foo)
333{
334 struct dlmfs_inode_private *ip =
335 (struct dlmfs_inode_private *) foo;
336
337 ip->ip_conn = NULL;
338 ip->ip_parent = NULL;
339
340 inode_init_once(&ip->ip_vfs_inode);
341}
342
343static struct inode *dlmfs_alloc_inode(struct super_block *sb)
344{
345 struct dlmfs_inode_private *ip;
346
347 ip = kmem_cache_alloc(dlmfs_inode_cache, GFP_NOFS);
348 if (!ip)
349 return NULL;
350
351 return &ip->ip_vfs_inode;
352}
353
354static void dlmfs_i_callback(struct rcu_head *head)
355{
356 struct inode *inode = container_of(head, struct inode, i_rcu);
357 kmem_cache_free(dlmfs_inode_cache, DLMFS_I(inode));
358}
359
360static void dlmfs_destroy_inode(struct inode *inode)
361{
362 call_rcu(&inode->i_rcu, dlmfs_i_callback);
363}
364
365static void dlmfs_evict_inode(struct inode *inode)
366{
367 int status;
368 struct dlmfs_inode_private *ip;
369
370 clear_inode(inode);
371
372 mlog(0, "inode %lu\n", inode->i_ino);
373
374 ip = DLMFS_I(inode);
375
376 if (S_ISREG(inode->i_mode)) {
377 status = user_dlm_destroy_lock(&ip->ip_lockres);
378 if (status < 0)
379 mlog_errno(status);
380 iput(ip->ip_parent);
381 goto clear_fields;
382 }
383
384 mlog(0, "we're a directory, ip->ip_conn = 0x%p\n", ip->ip_conn);
385
386
387 if (ip->ip_conn)
388 user_dlm_unregister(ip->ip_conn);
389clear_fields:
390 ip->ip_parent = NULL;
391 ip->ip_conn = NULL;
392}
393
394static struct backing_dev_info dlmfs_backing_dev_info = {
395 .name = "ocfs2-dlmfs",
396 .ra_pages = 0,
397 .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK,
398};
399
400static struct inode *dlmfs_get_root_inode(struct super_block *sb)
401{
402 struct inode *inode = new_inode(sb);
403 umode_t mode = S_IFDIR | 0755;
404 struct dlmfs_inode_private *ip;
405
406 if (inode) {
407 ip = DLMFS_I(inode);
408
409 inode->i_ino = get_next_ino();
410 inode_init_owner(inode, NULL, mode);
411 inode->i_mapping->backing_dev_info = &dlmfs_backing_dev_info;
412 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
413 inc_nlink(inode);
414
415 inode->i_fop = &simple_dir_operations;
416 inode->i_op = &dlmfs_root_inode_operations;
417 }
418
419 return inode;
420}
421
422static struct inode *dlmfs_get_inode(struct inode *parent,
423 struct dentry *dentry,
424 umode_t mode)
425{
426 struct super_block *sb = parent->i_sb;
427 struct inode * inode = new_inode(sb);
428 struct dlmfs_inode_private *ip;
429
430 if (!inode)
431 return NULL;
432
433 inode->i_ino = get_next_ino();
434 inode_init_owner(inode, parent, mode);
435 inode->i_mapping->backing_dev_info = &dlmfs_backing_dev_info;
436 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
437
438 ip = DLMFS_I(inode);
439 ip->ip_conn = DLMFS_I(parent)->ip_conn;
440
441 switch (mode & S_IFMT) {
442 default:
443
444
445 BUG();
446 break;
447 case S_IFREG:
448 inode->i_op = &dlmfs_file_inode_operations;
449 inode->i_fop = &dlmfs_file_operations;
450
451 i_size_write(inode, DLM_LVB_LEN);
452
453 user_dlm_lock_res_init(&ip->ip_lockres, dentry);
454
455
456
457
458
459 ip->ip_parent = igrab(parent);
460 BUG_ON(!ip->ip_parent);
461 break;
462 case S_IFDIR:
463 inode->i_op = &dlmfs_dir_inode_operations;
464 inode->i_fop = &simple_dir_operations;
465
466
467
468 inc_nlink(inode);
469 break;
470 }
471 return inode;
472}
473
474
475
476
477
478static int dlmfs_mkdir(struct inode * dir,
479 struct dentry * dentry,
480 umode_t mode)
481{
482 int status;
483 struct inode *inode = NULL;
484 struct qstr *domain = &dentry->d_name;
485 struct dlmfs_inode_private *ip;
486 struct ocfs2_cluster_connection *conn;
487
488 mlog(0, "mkdir %.*s\n", domain->len, domain->name);
489
490
491 if (domain->len >= GROUP_NAME_MAX) {
492 status = -EINVAL;
493 mlog(ML_ERROR, "invalid domain name for directory.\n");
494 goto bail;
495 }
496
497 inode = dlmfs_get_inode(dir, dentry, mode | S_IFDIR);
498 if (!inode) {
499 status = -ENOMEM;
500 mlog_errno(status);
501 goto bail;
502 }
503
504 ip = DLMFS_I(inode);
505
506 conn = user_dlm_register(domain);
507 if (IS_ERR(conn)) {
508 status = PTR_ERR(conn);
509 mlog(ML_ERROR, "Error %d could not register domain \"%.*s\"\n",
510 status, domain->len, domain->name);
511 goto bail;
512 }
513 ip->ip_conn = conn;
514
515 inc_nlink(dir);
516 d_instantiate(dentry, inode);
517 dget(dentry);
518
519 status = 0;
520bail:
521 if (status < 0)
522 iput(inode);
523 return status;
524}
525
526static int dlmfs_create(struct inode *dir,
527 struct dentry *dentry,
528 umode_t mode,
529 bool excl)
530{
531 int status = 0;
532 struct inode *inode;
533 struct qstr *name = &dentry->d_name;
534
535 mlog(0, "create %.*s\n", name->len, name->name);
536
537
538
539 if (name->len >= USER_DLM_LOCK_ID_MAX_LEN ||
540 name->name[0] == '$') {
541 status = -EINVAL;
542 mlog(ML_ERROR, "invalid lock name, %.*s\n", name->len,
543 name->name);
544 goto bail;
545 }
546
547 inode = dlmfs_get_inode(dir, dentry, mode | S_IFREG);
548 if (!inode) {
549 status = -ENOMEM;
550 mlog_errno(status);
551 goto bail;
552 }
553
554 d_instantiate(dentry, inode);
555 dget(dentry);
556bail:
557 return status;
558}
559
560static int dlmfs_unlink(struct inode *dir,
561 struct dentry *dentry)
562{
563 int status;
564 struct inode *inode = dentry->d_inode;
565
566 mlog(0, "unlink inode %lu\n", inode->i_ino);
567
568
569
570 status = user_dlm_destroy_lock(&DLMFS_I(inode)->ip_lockres);
571 if (status < 0) {
572 mlog(ML_ERROR, "unlink %.*s, error %d from destroy\n",
573 dentry->d_name.len, dentry->d_name.name, status);
574 goto bail;
575 }
576 status = simple_unlink(dir, dentry);
577bail:
578 return status;
579}
580
581static int dlmfs_fill_super(struct super_block * sb,
582 void * data,
583 int silent)
584{
585 sb->s_maxbytes = MAX_LFS_FILESIZE;
586 sb->s_blocksize = PAGE_CACHE_SIZE;
587 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
588 sb->s_magic = DLMFS_MAGIC;
589 sb->s_op = &dlmfs_ops;
590 sb->s_root = d_make_root(dlmfs_get_root_inode(sb));
591 if (!sb->s_root)
592 return -ENOMEM;
593 return 0;
594}
595
596static const struct file_operations dlmfs_file_operations = {
597 .open = dlmfs_file_open,
598 .release = dlmfs_file_release,
599 .poll = dlmfs_file_poll,
600 .read = dlmfs_file_read,
601 .write = dlmfs_file_write,
602 .llseek = default_llseek,
603};
604
605static const struct inode_operations dlmfs_dir_inode_operations = {
606 .create = dlmfs_create,
607 .lookup = simple_lookup,
608 .unlink = dlmfs_unlink,
609};
610
611
612static const struct inode_operations dlmfs_root_inode_operations = {
613 .lookup = simple_lookup,
614 .mkdir = dlmfs_mkdir,
615 .rmdir = simple_rmdir,
616};
617
618static const struct super_operations dlmfs_ops = {
619 .statfs = simple_statfs,
620 .alloc_inode = dlmfs_alloc_inode,
621 .destroy_inode = dlmfs_destroy_inode,
622 .evict_inode = dlmfs_evict_inode,
623 .drop_inode = generic_delete_inode,
624};
625
626static const struct inode_operations dlmfs_file_inode_operations = {
627 .getattr = simple_getattr,
628 .setattr = dlmfs_file_setattr,
629};
630
631static struct dentry *dlmfs_mount(struct file_system_type *fs_type,
632 int flags, const char *dev_name, void *data)
633{
634 return mount_nodev(fs_type, flags, data, dlmfs_fill_super);
635}
636
637static struct file_system_type dlmfs_fs_type = {
638 .owner = THIS_MODULE,
639 .name = "ocfs2_dlmfs",
640 .mount = dlmfs_mount,
641 .kill_sb = kill_litter_super,
642};
643MODULE_ALIAS_FS("ocfs2_dlmfs");
644
645static int __init init_dlmfs_fs(void)
646{
647 int status;
648 int cleanup_inode = 0, cleanup_worker = 0;
649
650 dlmfs_print_version();
651
652 status = bdi_init(&dlmfs_backing_dev_info);
653 if (status)
654 return status;
655
656 dlmfs_inode_cache = kmem_cache_create("dlmfs_inode_cache",
657 sizeof(struct dlmfs_inode_private),
658 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
659 SLAB_MEM_SPREAD),
660 dlmfs_init_once);
661 if (!dlmfs_inode_cache) {
662 status = -ENOMEM;
663 goto bail;
664 }
665 cleanup_inode = 1;
666
667 user_dlm_worker = create_singlethread_workqueue("user_dlm");
668 if (!user_dlm_worker) {
669 status = -ENOMEM;
670 goto bail;
671 }
672 cleanup_worker = 1;
673
674 user_dlm_set_locking_protocol();
675 status = register_filesystem(&dlmfs_fs_type);
676bail:
677 if (status) {
678 if (cleanup_inode)
679 kmem_cache_destroy(dlmfs_inode_cache);
680 if (cleanup_worker)
681 destroy_workqueue(user_dlm_worker);
682 bdi_destroy(&dlmfs_backing_dev_info);
683 } else
684 printk("OCFS2 User DLM kernel interface loaded\n");
685 return status;
686}
687
688static void __exit exit_dlmfs_fs(void)
689{
690 unregister_filesystem(&dlmfs_fs_type);
691
692 flush_workqueue(user_dlm_worker);
693 destroy_workqueue(user_dlm_worker);
694
695
696
697
698
699 rcu_barrier();
700 kmem_cache_destroy(dlmfs_inode_cache);
701
702 bdi_destroy(&dlmfs_backing_dev_info);
703}
704
705MODULE_AUTHOR("Oracle");
706MODULE_LICENSE("GPL");
707
708module_init(init_dlmfs_fs)
709module_exit(exit_dlmfs_fs)
710