blob: 920f0165edf31f0feb4daff0d85f827825557186 [file] [log] [blame]
Boaz Harroshba9e5e92008-10-28 16:11:41 +02001/*
2 * Copyright (C) 2005, 2006
Boaz Harrosh27d2e142009-06-14 17:23:09 +03003 * Avishay Traeger (avishay@gmail.com)
Boaz Harroshba9e5e92008-10-28 16:11:41 +02004 * Copyright (C) 2008, 2009
5 * Boaz Harrosh <bharrosh@panasas.com>
6 *
7 * Copyrights for code taken from ext2:
8 * Copyright (C) 1992, 1993, 1994, 1995
9 * Remy Card (card@masi.ibp.fr)
10 * Laboratoire MASI - Institut Blaise Pascal
11 * Universite Pierre et Marie Curie (Paris VI)
12 * from
13 * linux/fs/minix/inode.c
14 * Copyright (C) 1991, 1992 Linus Torvalds
15 *
16 * This file is part of exofs.
17 *
18 * exofs is free software; you can redistribute it and/or modify
19 * it under the terms of the GNU General Public License as published by
20 * the Free Software Foundation. Since it is based on ext2, and the only
21 * valid version of GPL for the Linux kernel is version 2, the only valid
22 * version of GPL for exofs is version 2.
23 *
24 * exofs is distributed in the hope that it will be useful,
25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27 * GNU General Public License for more details.
28 *
29 * You should have received a copy of the GNU General Public License
30 * along with exofs; if not, write to the Free Software
31 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
32 */
33
Alexey Dobriyan405f5572009-07-11 22:08:37 +040034#include <linux/smp_lock.h>
Boaz Harroshba9e5e92008-10-28 16:11:41 +020035#include <linux/string.h>
36#include <linux/parser.h>
37#include <linux/vfs.h>
38#include <linux/random.h>
Boaz Harrosh8cf74b32009-03-22 12:47:26 +020039#include <linux/exportfs.h>
Boaz Harroshba9e5e92008-10-28 16:11:41 +020040
41#include "exofs.h"
42
43/******************************************************************************
44 * MOUNT OPTIONS
45 *****************************************************************************/
46
47/*
48 * struct to hold what we get from mount options
49 */
50struct exofs_mountopt {
51 const char *dev_name;
52 uint64_t pid;
53 int timeout;
54};
55
56/*
57 * exofs-specific mount-time options.
58 */
59enum { Opt_pid, Opt_to, Opt_mkfs, Opt_format, Opt_err };
60
61/*
62 * Our mount-time options. These should ideally be 64-bit unsigned, but the
63 * kernel's parsing functions do not currently support that. 32-bit should be
64 * sufficient for most applications now.
65 */
66static match_table_t tokens = {
67 {Opt_pid, "pid=%u"},
68 {Opt_to, "to=%u"},
69 {Opt_err, NULL}
70};
71
72/*
73 * The main option parsing method. Also makes sure that all of the mandatory
74 * mount options were set.
75 */
76static int parse_options(char *options, struct exofs_mountopt *opts)
77{
78 char *p;
79 substring_t args[MAX_OPT_ARGS];
80 int option;
81 bool s_pid = false;
82
83 EXOFS_DBGMSG("parse_options %s\n", options);
84 /* defaults */
85 memset(opts, 0, sizeof(*opts));
86 opts->timeout = BLK_DEFAULT_SG_TIMEOUT;
87
88 while ((p = strsep(&options, ",")) != NULL) {
89 int token;
90 char str[32];
91
92 if (!*p)
93 continue;
94
95 token = match_token(p, tokens, args);
96 switch (token) {
97 case Opt_pid:
98 if (0 == match_strlcpy(str, &args[0], sizeof(str)))
99 return -EINVAL;
100 opts->pid = simple_strtoull(str, NULL, 0);
101 if (opts->pid < EXOFS_MIN_PID) {
102 EXOFS_ERR("Partition ID must be >= %u",
103 EXOFS_MIN_PID);
104 return -EINVAL;
105 }
106 s_pid = 1;
107 break;
108 case Opt_to:
109 if (match_int(&args[0], &option))
110 return -EINVAL;
111 if (option <= 0) {
112 EXOFS_ERR("Timout must be > 0");
113 return -EINVAL;
114 }
115 opts->timeout = option * HZ;
116 break;
117 }
118 }
119
120 if (!s_pid) {
121 EXOFS_ERR("Need to specify the following options:\n");
122 EXOFS_ERR(" -o pid=pid_no_to_use\n");
123 return -EINVAL;
124 }
125
126 return 0;
127}
128
129/******************************************************************************
130 * INODE CACHE
131 *****************************************************************************/
132
133/*
134 * Our inode cache. Isn't it pretty?
135 */
136static struct kmem_cache *exofs_inode_cachep;
137
138/*
139 * Allocate an inode in the cache
140 */
141static struct inode *exofs_alloc_inode(struct super_block *sb)
142{
143 struct exofs_i_info *oi;
144
145 oi = kmem_cache_alloc(exofs_inode_cachep, GFP_KERNEL);
146 if (!oi)
147 return NULL;
148
149 oi->vfs_inode.i_version = 1;
150 return &oi->vfs_inode;
151}
152
153/*
154 * Remove an inode from the cache
155 */
156static void exofs_destroy_inode(struct inode *inode)
157{
158 kmem_cache_free(exofs_inode_cachep, exofs_i(inode));
159}
160
161/*
162 * Initialize the inode
163 */
164static void exofs_init_once(void *foo)
165{
166 struct exofs_i_info *oi = foo;
167
168 inode_init_once(&oi->vfs_inode);
169}
170
171/*
172 * Create and initialize the inode cache
173 */
174static int init_inodecache(void)
175{
176 exofs_inode_cachep = kmem_cache_create("exofs_inode_cache",
177 sizeof(struct exofs_i_info), 0,
178 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
179 exofs_init_once);
180 if (exofs_inode_cachep == NULL)
181 return -ENOMEM;
182 return 0;
183}
184
185/*
186 * Destroy the inode cache
187 */
188static void destroy_inodecache(void)
189{
190 kmem_cache_destroy(exofs_inode_cachep);
191}
192
193/******************************************************************************
194 * SUPERBLOCK FUNCTIONS
195 *****************************************************************************/
196static const struct super_operations exofs_sops;
Boaz Harrosh8cf74b32009-03-22 12:47:26 +0200197static const struct export_operations exofs_export_ops;
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200198
199/*
200 * Write the superblock to the OSD
201 */
Boaz Harroshbaaf94c2009-06-14 16:52:10 +0300202int exofs_sync_fs(struct super_block *sb, int wait)
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200203{
204 struct exofs_sb_info *sbi;
205 struct exofs_fscb *fscb;
206 struct osd_request *or;
207 struct osd_obj_id obj;
Christoph Hellwig80e09fb2009-06-08 10:03:58 +0200208 int ret = -ENOMEM;
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200209
210 fscb = kzalloc(sizeof(struct exofs_fscb), GFP_KERNEL);
211 if (!fscb) {
212 EXOFS_ERR("exofs_write_super: memory allocation failed.\n");
Christoph Hellwig80e09fb2009-06-08 10:03:58 +0200213 return -ENOMEM;
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200214 }
215
Christoph Hellwigebc1ac12009-05-11 23:35:03 +0200216 lock_super(sb);
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200217 sbi = sb->s_fs_info;
218 fscb->s_nextid = cpu_to_le64(sbi->s_nextid);
219 fscb->s_numfiles = cpu_to_le32(sbi->s_numfiles);
220 fscb->s_magic = cpu_to_le16(sb->s_magic);
221 fscb->s_newfs = 0;
222
223 or = osd_start_request(sbi->s_dev, GFP_KERNEL);
224 if (unlikely(!or)) {
225 EXOFS_ERR("exofs_write_super: osd_start_request failed.\n");
226 goto out;
227 }
228
229 obj.partition = sbi->s_pid;
230 obj.id = EXOFS_SUPER_ID;
231 ret = osd_req_write_kern(or, &obj, 0, fscb, sizeof(*fscb));
232 if (unlikely(ret)) {
233 EXOFS_ERR("exofs_write_super: osd_req_write_kern failed.\n");
234 goto out;
235 }
236
237 ret = exofs_sync_op(or, sbi->s_timeout, sbi->s_cred);
238 if (unlikely(ret)) {
239 EXOFS_ERR("exofs_write_super: exofs_sync_op failed.\n");
240 goto out;
241 }
242 sb->s_dirt = 0;
243
244out:
245 if (or)
246 osd_end_request(or);
Christoph Hellwigebc1ac12009-05-11 23:35:03 +0200247 unlock_super(sb);
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200248 kfree(fscb);
Christoph Hellwig80e09fb2009-06-08 10:03:58 +0200249 return ret;
250}
251
252static void exofs_write_super(struct super_block *sb)
253{
254 if (!(sb->s_flags & MS_RDONLY))
255 exofs_sync_fs(sb, 1);
256 else
257 sb->s_dirt = 0;
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200258}
259
Boaz Harrosh19fe2942009-09-03 20:38:02 +0300260static void _exofs_print_device(const char *msg, const char *dev_path,
261 struct osd_dev *od, u64 pid)
262{
263 const struct osd_dev_info *odi = osduld_device_info(od);
264
265 printk(KERN_NOTICE "exofs: %s %s osd_name-%s pid-0x%llx\n",
266 msg, dev_path ?: "", odi->osdname, _LLU(pid));
267}
268
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200269/*
270 * This function is called when the vfs is freeing the superblock. We just
271 * need to free our own part.
272 */
273static void exofs_put_super(struct super_block *sb)
274{
275 int num_pend;
276 struct exofs_sb_info *sbi = sb->s_fs_info;
277
Christoph Hellwig8c85e122009-04-28 18:00:26 +0200278 if (sb->s_dirt)
279 exofs_write_super(sb);
280
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200281 /* make sure there are no pending commands */
282 for (num_pend = atomic_read(&sbi->s_curr_pending); num_pend > 0;
283 num_pend = atomic_read(&sbi->s_curr_pending)) {
284 wait_queue_head_t wq;
285 init_waitqueue_head(&wq);
286 wait_event_timeout(wq,
287 (atomic_read(&sbi->s_curr_pending) == 0),
288 msecs_to_jiffies(100));
289 }
290
Boaz Harrosh19fe2942009-09-03 20:38:02 +0300291 _exofs_print_device("Unmounting", NULL, sbi->s_dev, sbi->s_pid);
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200292 osduld_put_device(sbi->s_dev);
293 kfree(sb->s_fs_info);
294 sb->s_fs_info = NULL;
295}
296
297/*
298 * Read the superblock from the OSD and fill in the fields
299 */
300static int exofs_fill_super(struct super_block *sb, void *data, int silent)
301{
302 struct inode *root;
303 struct exofs_mountopt *opts = data;
304 struct exofs_sb_info *sbi; /*extended info */
305 struct exofs_fscb fscb; /*on-disk superblock info */
306 struct osd_request *or = NULL;
307 struct osd_obj_id obj;
308 int ret;
309
310 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
311 if (!sbi)
312 return -ENOMEM;
313 sb->s_fs_info = sbi;
314
315 /* use mount options to fill superblock */
316 sbi->s_dev = osduld_path_lookup(opts->dev_name);
317 if (IS_ERR(sbi->s_dev)) {
318 ret = PTR_ERR(sbi->s_dev);
319 sbi->s_dev = NULL;
320 goto free_sbi;
321 }
322
323 sbi->s_pid = opts->pid;
324 sbi->s_timeout = opts->timeout;
325
326 /* fill in some other data by hand */
327 memset(sb->s_id, 0, sizeof(sb->s_id));
328 strcpy(sb->s_id, "exofs");
329 sb->s_blocksize = EXOFS_BLKSIZE;
330 sb->s_blocksize_bits = EXOFS_BLKSHIFT;
331 sb->s_maxbytes = MAX_LFS_FILESIZE;
332 atomic_set(&sbi->s_curr_pending, 0);
333 sb->s_bdev = NULL;
334 sb->s_dev = 0;
335
336 /* read data from on-disk superblock object */
337 obj.partition = sbi->s_pid;
338 obj.id = EXOFS_SUPER_ID;
339 exofs_make_credential(sbi->s_cred, &obj);
340
341 or = osd_start_request(sbi->s_dev, GFP_KERNEL);
342 if (unlikely(!or)) {
343 if (!silent)
344 EXOFS_ERR(
345 "exofs_fill_super: osd_start_request failed.\n");
346 ret = -ENOMEM;
347 goto free_sbi;
348 }
349 ret = osd_req_read_kern(or, &obj, 0, &fscb, sizeof(fscb));
350 if (unlikely(ret)) {
351 if (!silent)
352 EXOFS_ERR(
353 "exofs_fill_super: osd_req_read_kern failed.\n");
354 ret = -ENOMEM;
355 goto free_sbi;
356 }
357
358 ret = exofs_sync_op(or, sbi->s_timeout, sbi->s_cred);
359 if (unlikely(ret)) {
360 if (!silent)
361 EXOFS_ERR("exofs_fill_super: exofs_sync_op failed.\n");
362 ret = -EIO;
363 goto free_sbi;
364 }
365
366 sb->s_magic = le16_to_cpu(fscb.s_magic);
367 sbi->s_nextid = le64_to_cpu(fscb.s_nextid);
368 sbi->s_numfiles = le32_to_cpu(fscb.s_numfiles);
369
370 /* make sure what we read from the object store is correct */
371 if (sb->s_magic != EXOFS_SUPER_MAGIC) {
372 if (!silent)
373 EXOFS_ERR("ERROR: Bad magic value\n");
374 ret = -EINVAL;
375 goto free_sbi;
376 }
377
378 /* start generation numbers from a random point */
379 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
380 spin_lock_init(&sbi->s_next_gen_lock);
381
382 /* set up operation vectors */
383 sb->s_op = &exofs_sops;
Boaz Harrosh8cf74b32009-03-22 12:47:26 +0200384 sb->s_export_op = &exofs_export_ops;
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200385 root = exofs_iget(sb, EXOFS_ROOT_ID - EXOFS_OBJ_OFF);
386 if (IS_ERR(root)) {
387 EXOFS_ERR("ERROR: exofs_iget failed\n");
388 ret = PTR_ERR(root);
389 goto free_sbi;
390 }
391 sb->s_root = d_alloc_root(root);
392 if (!sb->s_root) {
393 iput(root);
394 EXOFS_ERR("ERROR: get root inode failed\n");
395 ret = -ENOMEM;
396 goto free_sbi;
397 }
398
399 if (!S_ISDIR(root->i_mode)) {
400 dput(sb->s_root);
401 sb->s_root = NULL;
402 EXOFS_ERR("ERROR: corrupt root inode (mode = %hd)\n",
403 root->i_mode);
404 ret = -EINVAL;
405 goto free_sbi;
406 }
407
Boaz Harrosh19fe2942009-09-03 20:38:02 +0300408 _exofs_print_device("Mounting", opts->dev_name, sbi->s_dev, sbi->s_pid);
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200409 ret = 0;
410out:
411 if (or)
412 osd_end_request(or);
413 return ret;
414
415free_sbi:
416 osduld_put_device(sbi->s_dev); /* NULL safe */
417 kfree(sbi);
418 goto out;
419}
420
421/*
422 * Set up the superblock (calls exofs_fill_super eventually)
423 */
424static int exofs_get_sb(struct file_system_type *type,
425 int flags, const char *dev_name,
426 void *data, struct vfsmount *mnt)
427{
428 struct exofs_mountopt opts;
429 int ret;
430
431 ret = parse_options(data, &opts);
432 if (ret)
433 return ret;
434
435 opts.dev_name = dev_name;
436 return get_sb_nodev(type, flags, &opts, exofs_fill_super, mnt);
437}
438
439/*
440 * Return information about the file system state in the buffer. This is used
441 * by the 'df' command, for example.
442 */
443static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
444{
445 struct super_block *sb = dentry->d_sb;
446 struct exofs_sb_info *sbi = sb->s_fs_info;
447 struct osd_obj_id obj = {sbi->s_pid, 0};
448 struct osd_attr attrs[] = {
449 ATTR_DEF(OSD_APAGE_PARTITION_QUOTAS,
450 OSD_ATTR_PQ_CAPACITY_QUOTA, sizeof(__be64)),
451 ATTR_DEF(OSD_APAGE_PARTITION_INFORMATION,
452 OSD_ATTR_PI_USED_CAPACITY, sizeof(__be64)),
453 };
454 uint64_t capacity = ULLONG_MAX;
455 uint64_t used = ULLONG_MAX;
456 struct osd_request *or;
457 uint8_t cred_a[OSD_CAP_LEN];
458 int ret;
459
460 /* get used/capacity attributes */
461 exofs_make_credential(cred_a, &obj);
462
463 or = osd_start_request(sbi->s_dev, GFP_KERNEL);
464 if (unlikely(!or)) {
465 EXOFS_DBGMSG("exofs_statfs: osd_start_request failed.\n");
466 return -ENOMEM;
467 }
468
469 osd_req_get_attributes(or, &obj);
470 osd_req_add_get_attr_list(or, attrs, ARRAY_SIZE(attrs));
471 ret = exofs_sync_op(or, sbi->s_timeout, cred_a);
472 if (unlikely(ret))
473 goto out;
474
475 ret = extract_attr_from_req(or, &attrs[0]);
476 if (likely(!ret))
477 capacity = get_unaligned_be64(attrs[0].val_ptr);
478 else
479 EXOFS_DBGMSG("exofs_statfs: get capacity failed.\n");
480
481 ret = extract_attr_from_req(or, &attrs[1]);
482 if (likely(!ret))
483 used = get_unaligned_be64(attrs[1].val_ptr);
484 else
485 EXOFS_DBGMSG("exofs_statfs: get used-space failed.\n");
486
487 /* fill in the stats buffer */
488 buf->f_type = EXOFS_SUPER_MAGIC;
489 buf->f_bsize = EXOFS_BLKSIZE;
490 buf->f_blocks = (capacity >> EXOFS_BLKSHIFT);
491 buf->f_bfree = ((capacity - used) >> EXOFS_BLKSHIFT);
492 buf->f_bavail = buf->f_bfree;
493 buf->f_files = sbi->s_numfiles;
494 buf->f_ffree = EXOFS_MAX_ID - sbi->s_numfiles;
495 buf->f_namelen = EXOFS_NAME_LEN;
496
497out:
498 osd_end_request(or);
499 return ret;
500}
501
502static const struct super_operations exofs_sops = {
503 .alloc_inode = exofs_alloc_inode,
504 .destroy_inode = exofs_destroy_inode,
505 .write_inode = exofs_write_inode,
506 .delete_inode = exofs_delete_inode,
507 .put_super = exofs_put_super,
508 .write_super = exofs_write_super,
Christoph Hellwig80e09fb2009-06-08 10:03:58 +0200509 .sync_fs = exofs_sync_fs,
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200510 .statfs = exofs_statfs,
511};
512
513/******************************************************************************
Boaz Harrosh8cf74b32009-03-22 12:47:26 +0200514 * EXPORT OPERATIONS
515 *****************************************************************************/
516
517struct dentry *exofs_get_parent(struct dentry *child)
518{
519 unsigned long ino = exofs_parent_ino(child);
520
521 if (!ino)
522 return NULL;
523
524 return d_obtain_alias(exofs_iget(child->d_inode->i_sb, ino));
525}
526
527static struct inode *exofs_nfs_get_inode(struct super_block *sb,
528 u64 ino, u32 generation)
529{
530 struct inode *inode;
531
532 inode = exofs_iget(sb, ino);
533 if (IS_ERR(inode))
534 return ERR_CAST(inode);
535 if (generation && inode->i_generation != generation) {
536 /* we didn't find the right inode.. */
537 iput(inode);
538 return ERR_PTR(-ESTALE);
539 }
540 return inode;
541}
542
543static struct dentry *exofs_fh_to_dentry(struct super_block *sb,
544 struct fid *fid, int fh_len, int fh_type)
545{
546 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
547 exofs_nfs_get_inode);
548}
549
550static struct dentry *exofs_fh_to_parent(struct super_block *sb,
551 struct fid *fid, int fh_len, int fh_type)
552{
553 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
554 exofs_nfs_get_inode);
555}
556
557static const struct export_operations exofs_export_ops = {
558 .fh_to_dentry = exofs_fh_to_dentry,
559 .fh_to_parent = exofs_fh_to_parent,
560 .get_parent = exofs_get_parent,
561};
562
563/******************************************************************************
Boaz Harroshba9e5e92008-10-28 16:11:41 +0200564 * INSMOD/RMMOD
565 *****************************************************************************/
566
567/*
568 * struct that describes this file system
569 */
570static struct file_system_type exofs_type = {
571 .owner = THIS_MODULE,
572 .name = "exofs",
573 .get_sb = exofs_get_sb,
574 .kill_sb = generic_shutdown_super,
575};
576
577static int __init init_exofs(void)
578{
579 int err;
580
581 err = init_inodecache();
582 if (err)
583 goto out;
584
585 err = register_filesystem(&exofs_type);
586 if (err)
587 goto out_d;
588
589 return 0;
590out_d:
591 destroy_inodecache();
592out:
593 return err;
594}
595
596static void __exit exit_exofs(void)
597{
598 unregister_filesystem(&exofs_type);
599 destroy_inodecache();
600}
601
602MODULE_AUTHOR("Avishay Traeger <avishay@gmail.com>");
603MODULE_DESCRIPTION("exofs");
604MODULE_LICENSE("GPL");
605
606module_init(init_exofs)
607module_exit(exit_exofs)