Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / exofs / super.c
1 /*
2  * Copyright (C) 2005, 2006
3  * Avishay Traeger (avishay@gmail.com)
4  * Copyright (C) 2008, 2009
5  * Boaz Harrosh <ooo@electrozaur.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
34 #include <linux/string.h>
35 #include <linux/parser.h>
36 #include <linux/vfs.h>
37 #include <linux/random.h>
38 #include <linux/module.h>
39 #include <linux/exportfs.h>
40 #include <linux/slab.h>
41
42 #include "exofs.h"
43
44 #define EXOFS_DBGMSG2(M...) do {} while (0)
45
46 /******************************************************************************
47  * MOUNT OPTIONS
48  *****************************************************************************/
49
50 /*
51  * struct to hold what we get from mount options
52  */
53 struct exofs_mountopt {
54         bool is_osdname;
55         const char *dev_name;
56         uint64_t pid;
57         int timeout;
58 };
59
60 /*
61  * exofs-specific mount-time options.
62  */
63 enum { Opt_name, Opt_pid, Opt_to, Opt_err };
64
65 /*
66  * Our mount-time options.  These should ideally be 64-bit unsigned, but the
67  * kernel's parsing functions do not currently support that.  32-bit should be
68  * sufficient for most applications now.
69  */
70 static match_table_t tokens = {
71         {Opt_name, "osdname=%s"},
72         {Opt_pid, "pid=%u"},
73         {Opt_to, "to=%u"},
74         {Opt_err, NULL}
75 };
76
77 /*
78  * The main option parsing method.  Also makes sure that all of the mandatory
79  * mount options were set.
80  */
81 static int parse_options(char *options, struct exofs_mountopt *opts)
82 {
83         char *p;
84         substring_t args[MAX_OPT_ARGS];
85         int option;
86         bool s_pid = false;
87
88         EXOFS_DBGMSG("parse_options %s\n", options);
89         /* defaults */
90         memset(opts, 0, sizeof(*opts));
91         opts->timeout = BLK_DEFAULT_SG_TIMEOUT;
92
93         while ((p = strsep(&options, ",")) != NULL) {
94                 int token;
95                 char str[32];
96
97                 if (!*p)
98                         continue;
99
100                 token = match_token(p, tokens, args);
101                 switch (token) {
102                 case Opt_name:
103                         opts->dev_name = match_strdup(&args[0]);
104                         if (unlikely(!opts->dev_name)) {
105                                 EXOFS_ERR("Error allocating dev_name");
106                                 return -ENOMEM;
107                         }
108                         opts->is_osdname = true;
109                         break;
110                 case Opt_pid:
111                         if (0 == match_strlcpy(str, &args[0], sizeof(str)))
112                                 return -EINVAL;
113                         opts->pid = simple_strtoull(str, NULL, 0);
114                         if (opts->pid < EXOFS_MIN_PID) {
115                                 EXOFS_ERR("Partition ID must be >= %u",
116                                           EXOFS_MIN_PID);
117                                 return -EINVAL;
118                         }
119                         s_pid = 1;
120                         break;
121                 case Opt_to:
122                         if (match_int(&args[0], &option))
123                                 return -EINVAL;
124                         if (option <= 0) {
125                                 EXOFS_ERR("Timout must be > 0");
126                                 return -EINVAL;
127                         }
128                         opts->timeout = option * HZ;
129                         break;
130                 }
131         }
132
133         if (!s_pid) {
134                 EXOFS_ERR("Need to specify the following options:\n");
135                 EXOFS_ERR("    -o pid=pid_no_to_use\n");
136                 return -EINVAL;
137         }
138
139         return 0;
140 }
141
142 /******************************************************************************
143  * INODE CACHE
144  *****************************************************************************/
145
146 /*
147  * Our inode cache.  Isn't it pretty?
148  */
149 static struct kmem_cache *exofs_inode_cachep;
150
151 /*
152  * Allocate an inode in the cache
153  */
154 static struct inode *exofs_alloc_inode(struct super_block *sb)
155 {
156         struct exofs_i_info *oi;
157
158         oi = kmem_cache_alloc(exofs_inode_cachep, GFP_KERNEL);
159         if (!oi)
160                 return NULL;
161
162         oi->vfs_inode.i_version = 1;
163         return &oi->vfs_inode;
164 }
165
166 static void exofs_i_callback(struct rcu_head *head)
167 {
168         struct inode *inode = container_of(head, struct inode, i_rcu);
169         kmem_cache_free(exofs_inode_cachep, exofs_i(inode));
170 }
171
172 /*
173  * Remove an inode from the cache
174  */
175 static void exofs_destroy_inode(struct inode *inode)
176 {
177         call_rcu(&inode->i_rcu, exofs_i_callback);
178 }
179
180 /*
181  * Initialize the inode
182  */
183 static void exofs_init_once(void *foo)
184 {
185         struct exofs_i_info *oi = foo;
186
187         inode_init_once(&oi->vfs_inode);
188 }
189
190 /*
191  * Create and initialize the inode cache
192  */
193 static int init_inodecache(void)
194 {
195         exofs_inode_cachep = kmem_cache_create("exofs_inode_cache",
196                                 sizeof(struct exofs_i_info), 0,
197                                 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
198                                 exofs_init_once);
199         if (exofs_inode_cachep == NULL)
200                 return -ENOMEM;
201         return 0;
202 }
203
204 /*
205  * Destroy the inode cache
206  */
207 static void destroy_inodecache(void)
208 {
209         /*
210          * Make sure all delayed rcu free inodes are flushed before we
211          * destroy cache.
212          */
213         rcu_barrier();
214         kmem_cache_destroy(exofs_inode_cachep);
215 }
216
217 /******************************************************************************
218  * Some osd helpers
219  *****************************************************************************/
220 void exofs_make_credential(u8 cred_a[OSD_CAP_LEN], const struct osd_obj_id *obj)
221 {
222         osd_sec_init_nosec_doall_caps(cred_a, obj, false, true);
223 }
224
225 static int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
226                     u64 offset, void *p, unsigned length)
227 {
228         struct osd_request *or = osd_start_request(od, GFP_KERNEL);
229 /*      struct osd_sense_info osi = {.key = 0};*/
230         int ret;
231
232         if (unlikely(!or)) {
233                 EXOFS_DBGMSG("%s: osd_start_request failed.\n", __func__);
234                 return -ENOMEM;
235         }
236         ret = osd_req_read_kern(or, obj, offset, p, length);
237         if (unlikely(ret)) {
238                 EXOFS_DBGMSG("%s: osd_req_read_kern failed.\n", __func__);
239                 goto out;
240         }
241
242         ret = osd_finalize_request(or, 0, cred, NULL);
243         if (unlikely(ret)) {
244                 EXOFS_DBGMSG("Failed to osd_finalize_request() => %d\n", ret);
245                 goto out;
246         }
247
248         ret = osd_execute_request(or);
249         if (unlikely(ret))
250                 EXOFS_DBGMSG("osd_execute_request() => %d\n", ret);
251         /* osd_req_decode_sense(or, ret); */
252
253 out:
254         osd_end_request(or);
255         EXOFS_DBGMSG2("read_kern(0x%llx) offset=0x%llx "
256                       "length=0x%llx dev=%p ret=>%d\n",
257                       _LLU(obj->id), _LLU(offset), _LLU(length), od, ret);
258         return ret;
259 }
260
261 static const struct osd_attr g_attr_sb_stats = ATTR_DEF(
262         EXOFS_APAGE_SB_DATA,
263         EXOFS_ATTR_SB_STATS,
264         sizeof(struct exofs_sb_stats));
265
266 static int __sbi_read_stats(struct exofs_sb_info *sbi)
267 {
268         struct osd_attr attrs[] = {
269                 [0] = g_attr_sb_stats,
270         };
271         struct ore_io_state *ios;
272         int ret;
273
274         ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
275         if (unlikely(ret)) {
276                 EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
277                 return ret;
278         }
279
280         ios->in_attr = attrs;
281         ios->in_attr_len = ARRAY_SIZE(attrs);
282
283         ret = ore_read(ios);
284         if (unlikely(ret)) {
285                 EXOFS_ERR("Error reading super_block stats => %d\n", ret);
286                 goto out;
287         }
288
289         ret = extract_attr_from_ios(ios, &attrs[0]);
290         if (ret) {
291                 EXOFS_ERR("%s: extract_attr of sb_stats failed\n", __func__);
292                 goto out;
293         }
294         if (attrs[0].len) {
295                 struct exofs_sb_stats *ess;
296
297                 if (unlikely(attrs[0].len != sizeof(*ess))) {
298                         EXOFS_ERR("%s: Wrong version of exofs_sb_stats "
299                                   "size(%d) != expected(%zd)\n",
300                                   __func__, attrs[0].len, sizeof(*ess));
301                         goto out;
302                 }
303
304                 ess = attrs[0].val_ptr;
305                 sbi->s_nextid = le64_to_cpu(ess->s_nextid);
306                 sbi->s_numfiles = le32_to_cpu(ess->s_numfiles);
307         }
308
309 out:
310         ore_put_io_state(ios);
311         return ret;
312 }
313
314 static void stats_done(struct ore_io_state *ios, void *p)
315 {
316         ore_put_io_state(ios);
317         /* Good thanks nothing to do anymore */
318 }
319
320 /* Asynchronously write the stats attribute */
321 int exofs_sbi_write_stats(struct exofs_sb_info *sbi)
322 {
323         struct osd_attr attrs[] = {
324                 [0] = g_attr_sb_stats,
325         };
326         struct ore_io_state *ios;
327         int ret;
328
329         ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
330         if (unlikely(ret)) {
331                 EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
332                 return ret;
333         }
334
335         sbi->s_ess.s_nextid   = cpu_to_le64(sbi->s_nextid);
336         sbi->s_ess.s_numfiles = cpu_to_le64(sbi->s_numfiles);
337         attrs[0].val_ptr = &sbi->s_ess;
338
339
340         ios->done = stats_done;
341         ios->private = sbi;
342         ios->out_attr = attrs;
343         ios->out_attr_len = ARRAY_SIZE(attrs);
344
345         ret = ore_write(ios);
346         if (unlikely(ret)) {
347                 EXOFS_ERR("%s: ore_write failed.\n", __func__);
348                 ore_put_io_state(ios);
349         }
350
351         return ret;
352 }
353
354 /******************************************************************************
355  * SUPERBLOCK FUNCTIONS
356  *****************************************************************************/
357 static const struct super_operations exofs_sops;
358 static const struct export_operations exofs_export_ops;
359
360 /*
361  * Write the superblock to the OSD
362  */
363 static int exofs_sync_fs(struct super_block *sb, int wait)
364 {
365         struct exofs_sb_info *sbi;
366         struct exofs_fscb *fscb;
367         struct ore_comp one_comp;
368         struct ore_components oc;
369         struct ore_io_state *ios;
370         int ret = -ENOMEM;
371
372         fscb = kmalloc(sizeof(*fscb), GFP_KERNEL);
373         if (unlikely(!fscb))
374                 return -ENOMEM;
375
376         sbi = sb->s_fs_info;
377
378         /* NOTE: We no longer dirty the super_block anywhere in exofs. The
379          * reason we write the fscb here on unmount is so we can stay backwards
380          * compatible with fscb->s_version == 1. (What we are not compatible
381          * with is if a new version FS crashed and then we try to mount an old
382          * version). Otherwise the exofs_fscb is read-only from mkfs time. All
383          * the writeable info is set in exofs_sbi_write_stats() above.
384          */
385
386         exofs_init_comps(&oc, &one_comp, sbi, EXOFS_SUPER_ID);
387
388         ret = ore_get_io_state(&sbi->layout, &oc, &ios);
389         if (unlikely(ret))
390                 goto out;
391
392         ios->length = offsetof(struct exofs_fscb, s_dev_table_oid);
393         memset(fscb, 0, ios->length);
394         fscb->s_nextid = cpu_to_le64(sbi->s_nextid);
395         fscb->s_numfiles = cpu_to_le64(sbi->s_numfiles);
396         fscb->s_magic = cpu_to_le16(sb->s_magic);
397         fscb->s_newfs = 0;
398         fscb->s_version = EXOFS_FSCB_VER;
399
400         ios->offset = 0;
401         ios->kern_buff = fscb;
402
403         ret = ore_write(ios);
404         if (unlikely(ret))
405                 EXOFS_ERR("%s: ore_write failed.\n", __func__);
406
407 out:
408         EXOFS_DBGMSG("s_nextid=0x%llx ret=%d\n", _LLU(sbi->s_nextid), ret);
409         ore_put_io_state(ios);
410         kfree(fscb);
411         return ret;
412 }
413
414 static void _exofs_print_device(const char *msg, const char *dev_path,
415                                 struct osd_dev *od, u64 pid)
416 {
417         const struct osd_dev_info *odi = osduld_device_info(od);
418
419         printk(KERN_NOTICE "exofs: %s %s osd_name-%s pid-0x%llx\n",
420                 msg, dev_path ?: "", odi->osdname, _LLU(pid));
421 }
422
423 static void exofs_free_sbi(struct exofs_sb_info *sbi)
424 {
425         unsigned numdevs = sbi->oc.numdevs;
426
427         while (numdevs) {
428                 unsigned i = --numdevs;
429                 struct osd_dev *od = ore_comp_dev(&sbi->oc, i);
430
431                 if (od) {
432                         ore_comp_set_dev(&sbi->oc, i, NULL);
433                         osduld_put_device(od);
434                 }
435         }
436         kfree(sbi->oc.ods);
437         kfree(sbi);
438 }
439
440 /*
441  * This function is called when the vfs is freeing the superblock.  We just
442  * need to free our own part.
443  */
444 static void exofs_put_super(struct super_block *sb)
445 {
446         int num_pend;
447         struct exofs_sb_info *sbi = sb->s_fs_info;
448
449         /* make sure there are no pending commands */
450         for (num_pend = atomic_read(&sbi->s_curr_pending); num_pend > 0;
451              num_pend = atomic_read(&sbi->s_curr_pending)) {
452                 wait_queue_head_t wq;
453
454                 printk(KERN_NOTICE "%s: !!Pending operations in flight. "
455                        "This is a BUG. please report to osd-dev@open-osd.org\n",
456                        __func__);
457                 init_waitqueue_head(&wq);
458                 wait_event_timeout(wq,
459                                   (atomic_read(&sbi->s_curr_pending) == 0),
460                                   msecs_to_jiffies(100));
461         }
462
463         _exofs_print_device("Unmounting", NULL, ore_comp_dev(&sbi->oc, 0),
464                             sbi->one_comp.obj.partition);
465
466         exofs_sysfs_sb_del(sbi);
467         bdi_destroy(&sbi->bdi);
468         exofs_free_sbi(sbi);
469         sb->s_fs_info = NULL;
470 }
471
472 static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
473                                     struct exofs_device_table *dt)
474 {
475         int ret;
476
477         sbi->layout.stripe_unit =
478                                 le64_to_cpu(dt->dt_data_map.cb_stripe_unit);
479         sbi->layout.group_width =
480                                 le32_to_cpu(dt->dt_data_map.cb_group_width);
481         sbi->layout.group_depth =
482                                 le32_to_cpu(dt->dt_data_map.cb_group_depth);
483         sbi->layout.mirrors_p1  =
484                                 le32_to_cpu(dt->dt_data_map.cb_mirror_cnt) + 1;
485         sbi->layout.raid_algorithm  =
486                                 le32_to_cpu(dt->dt_data_map.cb_raid_algorithm);
487
488         ret = ore_verify_layout(numdevs, &sbi->layout);
489
490         EXOFS_DBGMSG("exofs: layout: "
491                 "num_comps=%u stripe_unit=0x%x group_width=%u "
492                 "group_depth=0x%llx mirrors_p1=%u raid_algorithm=%u\n",
493                 numdevs,
494                 sbi->layout.stripe_unit,
495                 sbi->layout.group_width,
496                 _LLU(sbi->layout.group_depth),
497                 sbi->layout.mirrors_p1,
498                 sbi->layout.raid_algorithm);
499         return ret;
500 }
501
502 static unsigned __ra_pages(struct ore_layout *layout)
503 {
504         const unsigned _MIN_RA = 32; /* min 128K read-ahead */
505         unsigned ra_pages = layout->group_width * layout->stripe_unit /
506                                 PAGE_SIZE;
507         unsigned max_io_pages = exofs_max_io_pages(layout, ~0);
508
509         ra_pages *= 2; /* two stripes */
510         if (ra_pages < _MIN_RA)
511                 ra_pages = roundup(_MIN_RA, ra_pages / 2);
512
513         if (ra_pages > max_io_pages)
514                 ra_pages = max_io_pages;
515
516         return ra_pages;
517 }
518
519 /* @odi is valid only as long as @fscb_dev is valid */
520 static int exofs_devs_2_odi(struct exofs_dt_device_info *dt_dev,
521                              struct osd_dev_info *odi)
522 {
523         odi->systemid_len = le32_to_cpu(dt_dev->systemid_len);
524         if (likely(odi->systemid_len))
525                 memcpy(odi->systemid, dt_dev->systemid, OSD_SYSTEMID_LEN);
526
527         odi->osdname_len = le32_to_cpu(dt_dev->osdname_len);
528         odi->osdname = dt_dev->osdname;
529
530         /* FIXME support long names. Will need a _put function */
531         if (dt_dev->long_name_offset)
532                 return -EINVAL;
533
534         /* Make sure osdname is printable!
535          * mkexofs should give us space for a null-terminator else the
536          * device-table is invalid.
537          */
538         if (unlikely(odi->osdname_len >= sizeof(dt_dev->osdname)))
539                 odi->osdname_len = sizeof(dt_dev->osdname) - 1;
540         dt_dev->osdname[odi->osdname_len] = 0;
541
542         /* If it's all zeros something is bad we read past end-of-obj */
543         return !(odi->systemid_len || odi->osdname_len);
544 }
545
546 static int __alloc_dev_table(struct exofs_sb_info *sbi, unsigned numdevs,
547                       struct exofs_dev **peds)
548 {
549         struct __alloc_ore_devs_and_exofs_devs {
550                 /* Twice bigger table: See exofs_init_comps() and comment at
551                  * exofs_read_lookup_dev_table()
552                  */
553                 struct ore_dev *oreds[numdevs * 2 - 1];
554                 struct exofs_dev eds[numdevs];
555         } *aoded;
556         struct exofs_dev *eds;
557         unsigned i;
558
559         aoded = kzalloc(sizeof(*aoded), GFP_KERNEL);
560         if (unlikely(!aoded)) {
561                 EXOFS_ERR("ERROR: failed allocating Device array[%d]\n",
562                           numdevs);
563                 return -ENOMEM;
564         }
565
566         sbi->oc.ods = aoded->oreds;
567         *peds = eds = aoded->eds;
568         for (i = 0; i < numdevs; ++i)
569                 aoded->oreds[i] = &eds[i].ored;
570         return 0;
571 }
572
573 static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi,
574                                        struct osd_dev *fscb_od,
575                                        unsigned table_count)
576 {
577         struct ore_comp comp;
578         struct exofs_device_table *dt;
579         struct exofs_dev *eds;
580         unsigned table_bytes = table_count * sizeof(dt->dt_dev_table[0]) +
581                                              sizeof(*dt);
582         unsigned numdevs, i;
583         int ret;
584
585         dt = kmalloc(table_bytes, GFP_KERNEL);
586         if (unlikely(!dt)) {
587                 EXOFS_ERR("ERROR: allocating %x bytes for device table\n",
588                           table_bytes);
589                 return -ENOMEM;
590         }
591
592         sbi->oc.numdevs = 0;
593
594         comp.obj.partition = sbi->one_comp.obj.partition;
595         comp.obj.id = EXOFS_DEVTABLE_ID;
596         exofs_make_credential(comp.cred, &comp.obj);
597
598         ret = exofs_read_kern(fscb_od, comp.cred, &comp.obj, 0, dt,
599                               table_bytes);
600         if (unlikely(ret)) {
601                 EXOFS_ERR("ERROR: reading device table\n");
602                 goto out;
603         }
604
605         numdevs = le64_to_cpu(dt->dt_num_devices);
606         if (unlikely(!numdevs)) {
607                 ret = -EINVAL;
608                 goto out;
609         }
610         WARN_ON(table_count != numdevs);
611
612         ret = _read_and_match_data_map(sbi, numdevs, dt);
613         if (unlikely(ret))
614                 goto out;
615
616         ret = __alloc_dev_table(sbi, numdevs, &eds);
617         if (unlikely(ret))
618                 goto out;
619         /* exofs round-robins the device table view according to inode
620          * number. We hold a: twice bigger table hence inodes can point
621          * to any device and have a sequential view of the table
622          * starting at this device. See exofs_init_comps()
623          */
624         memcpy(&sbi->oc.ods[numdevs], &sbi->oc.ods[0],
625                 (numdevs - 1) * sizeof(sbi->oc.ods[0]));
626
627         /* create sysfs subdir under which we put the device table
628          * And cluster layout. A Superblock is identified by the string:
629          *      "dev[0].osdname"_"pid"
630          */
631         exofs_sysfs_sb_add(sbi, &dt->dt_dev_table[0]);
632
633         for (i = 0; i < numdevs; i++) {
634                 struct exofs_fscb fscb;
635                 struct osd_dev_info odi;
636                 struct osd_dev *od;
637
638                 if (exofs_devs_2_odi(&dt->dt_dev_table[i], &odi)) {
639                         EXOFS_ERR("ERROR: Read all-zeros device entry\n");
640                         ret = -EINVAL;
641                         goto out;
642                 }
643
644                 printk(KERN_NOTICE "Add device[%d]: osd_name-%s\n",
645                        i, odi.osdname);
646
647                 /* the exofs id is currently the table index */
648                 eds[i].did = i;
649
650                 /* On all devices the device table is identical. The user can
651                  * specify any one of the participating devices on the command
652                  * line. We always keep them in device-table order.
653                  */
654                 if (fscb_od && osduld_device_same(fscb_od, &odi)) {
655                         eds[i].ored.od = fscb_od;
656                         ++sbi->oc.numdevs;
657                         fscb_od = NULL;
658                         exofs_sysfs_odev_add(&eds[i], sbi);
659                         continue;
660                 }
661
662                 od = osduld_info_lookup(&odi);
663                 if (IS_ERR(od)) {
664                         ret = PTR_ERR(od);
665                         EXOFS_ERR("ERROR: device requested is not found "
666                                   "osd_name-%s =>%d\n", odi.osdname, ret);
667                         goto out;
668                 }
669
670                 eds[i].ored.od = od;
671                 ++sbi->oc.numdevs;
672
673                 /* Read the fscb of the other devices to make sure the FS
674                  * partition is there.
675                  */
676                 ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb,
677                                       sizeof(fscb));
678                 if (unlikely(ret)) {
679                         EXOFS_ERR("ERROR: Malformed participating device "
680                                   "error reading fscb osd_name-%s\n",
681                                   odi.osdname);
682                         goto out;
683                 }
684                 exofs_sysfs_odev_add(&eds[i], sbi);
685
686                 /* TODO: verify other information is correct and FS-uuid
687                  *       matches. Benny what did you say about device table
688                  *       generation and old devices?
689                  */
690         }
691
692 out:
693         kfree(dt);
694         if (unlikely(fscb_od && !ret)) {
695                         EXOFS_ERR("ERROR: Bad device-table container device not present\n");
696                         osduld_put_device(fscb_od);
697                         return -EINVAL;
698         }
699         return ret;
700 }
701
702 /*
703  * Read the superblock from the OSD and fill in the fields
704  */
705 static int exofs_fill_super(struct super_block *sb, void *data, int silent)
706 {
707         struct inode *root;
708         struct exofs_mountopt *opts = data;
709         struct exofs_sb_info *sbi;      /*extended info                  */
710         struct osd_dev *od;             /* Master device                 */
711         struct exofs_fscb fscb;         /*on-disk superblock info        */
712         struct ore_comp comp;
713         unsigned table_count;
714         int ret;
715
716         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
717         if (!sbi)
718                 return -ENOMEM;
719
720         /* use mount options to fill superblock */
721         if (opts->is_osdname) {
722                 struct osd_dev_info odi = {.systemid_len = 0};
723
724                 odi.osdname_len = strlen(opts->dev_name);
725                 odi.osdname = (u8 *)opts->dev_name;
726                 od = osduld_info_lookup(&odi);
727                 kfree(opts->dev_name);
728                 opts->dev_name = NULL;
729         } else {
730                 od = osduld_path_lookup(opts->dev_name);
731         }
732         if (IS_ERR(od)) {
733                 ret = -EINVAL;
734                 goto free_sbi;
735         }
736
737         /* Default layout in case we do not have a device-table */
738         sbi->layout.stripe_unit = PAGE_SIZE;
739         sbi->layout.mirrors_p1 = 1;
740         sbi->layout.group_width = 1;
741         sbi->layout.group_depth = -1;
742         sbi->layout.group_count = 1;
743         sbi->s_timeout = opts->timeout;
744
745         sbi->one_comp.obj.partition = opts->pid;
746         sbi->one_comp.obj.id = 0;
747         exofs_make_credential(sbi->one_comp.cred, &sbi->one_comp.obj);
748         sbi->oc.single_comp = EC_SINGLE_COMP;
749         sbi->oc.comps = &sbi->one_comp;
750
751         /* fill in some other data by hand */
752         memset(sb->s_id, 0, sizeof(sb->s_id));
753         strcpy(sb->s_id, "exofs");
754         sb->s_blocksize = EXOFS_BLKSIZE;
755         sb->s_blocksize_bits = EXOFS_BLKSHIFT;
756         sb->s_maxbytes = MAX_LFS_FILESIZE;
757         sb->s_max_links = EXOFS_LINK_MAX;
758         atomic_set(&sbi->s_curr_pending, 0);
759         sb->s_bdev = NULL;
760         sb->s_dev = 0;
761
762         comp.obj.partition = sbi->one_comp.obj.partition;
763         comp.obj.id = EXOFS_SUPER_ID;
764         exofs_make_credential(comp.cred, &comp.obj);
765
766         ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb, sizeof(fscb));
767         if (unlikely(ret))
768                 goto free_sbi;
769
770         sb->s_magic = le16_to_cpu(fscb.s_magic);
771         /* NOTE: we read below to be backward compatible with old versions */
772         sbi->s_nextid = le64_to_cpu(fscb.s_nextid);
773         sbi->s_numfiles = le32_to_cpu(fscb.s_numfiles);
774
775         /* make sure what we read from the object store is correct */
776         if (sb->s_magic != EXOFS_SUPER_MAGIC) {
777                 if (!silent)
778                         EXOFS_ERR("ERROR: Bad magic value\n");
779                 ret = -EINVAL;
780                 goto free_sbi;
781         }
782         if (le32_to_cpu(fscb.s_version) > EXOFS_FSCB_VER) {
783                 EXOFS_ERR("ERROR: Bad FSCB version expected-%d got-%d\n",
784                           EXOFS_FSCB_VER, le32_to_cpu(fscb.s_version));
785                 ret = -EINVAL;
786                 goto free_sbi;
787         }
788
789         /* start generation numbers from a random point */
790         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
791         spin_lock_init(&sbi->s_next_gen_lock);
792
793         table_count = le64_to_cpu(fscb.s_dev_table_count);
794         if (table_count) {
795                 ret = exofs_read_lookup_dev_table(sbi, od, table_count);
796                 if (unlikely(ret))
797                         goto free_sbi;
798         } else {
799                 struct exofs_dev *eds;
800
801                 ret = __alloc_dev_table(sbi, 1, &eds);
802                 if (unlikely(ret))
803                         goto free_sbi;
804
805                 ore_comp_set_dev(&sbi->oc, 0, od);
806                 sbi->oc.numdevs = 1;
807         }
808
809         __sbi_read_stats(sbi);
810
811         /* set up operation vectors */
812         sbi->bdi.ra_pages = __ra_pages(&sbi->layout);
813         sb->s_bdi = &sbi->bdi;
814         sb->s_fs_info = sbi;
815         sb->s_op = &exofs_sops;
816         sb->s_export_op = &exofs_export_ops;
817         root = exofs_iget(sb, EXOFS_ROOT_ID - EXOFS_OBJ_OFF);
818         if (IS_ERR(root)) {
819                 EXOFS_ERR("ERROR: exofs_iget failed\n");
820                 ret = PTR_ERR(root);
821                 goto free_sbi;
822         }
823         sb->s_root = d_make_root(root);
824         if (!sb->s_root) {
825                 EXOFS_ERR("ERROR: get root inode failed\n");
826                 ret = -ENOMEM;
827                 goto free_sbi;
828         }
829
830         if (!S_ISDIR(root->i_mode)) {
831                 dput(sb->s_root);
832                 sb->s_root = NULL;
833                 EXOFS_ERR("ERROR: corrupt root inode (mode = %hd)\n",
834                        root->i_mode);
835                 ret = -EINVAL;
836                 goto free_sbi;
837         }
838
839         ret = bdi_setup_and_register(&sbi->bdi, "exofs");
840         if (ret) {
841                 EXOFS_DBGMSG("Failed to bdi_setup_and_register\n");
842                 dput(sb->s_root);
843                 sb->s_root = NULL;
844                 goto free_sbi;
845         }
846
847         exofs_sysfs_dbg_print();
848         _exofs_print_device("Mounting", opts->dev_name,
849                             ore_comp_dev(&sbi->oc, 0),
850                             sbi->one_comp.obj.partition);
851         return 0;
852
853 free_sbi:
854         EXOFS_ERR("Unable to mount exofs on %s pid=0x%llx err=%d\n",
855                   opts->dev_name, sbi->one_comp.obj.partition, ret);
856         exofs_free_sbi(sbi);
857         return ret;
858 }
859
860 /*
861  * Set up the superblock (calls exofs_fill_super eventually)
862  */
863 static struct dentry *exofs_mount(struct file_system_type *type,
864                           int flags, const char *dev_name,
865                           void *data)
866 {
867         struct exofs_mountopt opts;
868         int ret;
869
870         ret = parse_options(data, &opts);
871         if (ret)
872                 return ERR_PTR(ret);
873
874         if (!opts.dev_name)
875                 opts.dev_name = dev_name;
876         return mount_nodev(type, flags, &opts, exofs_fill_super);
877 }
878
879 /*
880  * Return information about the file system state in the buffer.  This is used
881  * by the 'df' command, for example.
882  */
883 static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
884 {
885         struct super_block *sb = dentry->d_sb;
886         struct exofs_sb_info *sbi = sb->s_fs_info;
887         struct ore_io_state *ios;
888         struct osd_attr attrs[] = {
889                 ATTR_DEF(OSD_APAGE_PARTITION_QUOTAS,
890                         OSD_ATTR_PQ_CAPACITY_QUOTA, sizeof(__be64)),
891                 ATTR_DEF(OSD_APAGE_PARTITION_INFORMATION,
892                         OSD_ATTR_PI_USED_CAPACITY, sizeof(__be64)),
893         };
894         uint64_t capacity = ULLONG_MAX;
895         uint64_t used = ULLONG_MAX;
896         int ret;
897
898         ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
899         if (ret) {
900                 EXOFS_DBGMSG("ore_get_io_state failed.\n");
901                 return ret;
902         }
903
904         ios->in_attr = attrs;
905         ios->in_attr_len = ARRAY_SIZE(attrs);
906
907         ret = ore_read(ios);
908         if (unlikely(ret))
909                 goto out;
910
911         ret = extract_attr_from_ios(ios, &attrs[0]);
912         if (likely(!ret)) {
913                 capacity = get_unaligned_be64(attrs[0].val_ptr);
914                 if (unlikely(!capacity))
915                         capacity = ULLONG_MAX;
916         } else
917                 EXOFS_DBGMSG("exofs_statfs: get capacity failed.\n");
918
919         ret = extract_attr_from_ios(ios, &attrs[1]);
920         if (likely(!ret))
921                 used = get_unaligned_be64(attrs[1].val_ptr);
922         else
923                 EXOFS_DBGMSG("exofs_statfs: get used-space failed.\n");
924
925         /* fill in the stats buffer */
926         buf->f_type = EXOFS_SUPER_MAGIC;
927         buf->f_bsize = EXOFS_BLKSIZE;
928         buf->f_blocks = capacity >> 9;
929         buf->f_bfree = (capacity - used) >> 9;
930         buf->f_bavail = buf->f_bfree;
931         buf->f_files = sbi->s_numfiles;
932         buf->f_ffree = EXOFS_MAX_ID - sbi->s_numfiles;
933         buf->f_namelen = EXOFS_NAME_LEN;
934
935 out:
936         ore_put_io_state(ios);
937         return ret;
938 }
939
940 static const struct super_operations exofs_sops = {
941         .alloc_inode    = exofs_alloc_inode,
942         .destroy_inode  = exofs_destroy_inode,
943         .write_inode    = exofs_write_inode,
944         .evict_inode    = exofs_evict_inode,
945         .put_super      = exofs_put_super,
946         .sync_fs        = exofs_sync_fs,
947         .statfs         = exofs_statfs,
948 };
949
950 /******************************************************************************
951  * EXPORT OPERATIONS
952  *****************************************************************************/
953
954 static struct dentry *exofs_get_parent(struct dentry *child)
955 {
956         unsigned long ino = exofs_parent_ino(child);
957
958         if (!ino)
959                 return ERR_PTR(-ESTALE);
960
961         return d_obtain_alias(exofs_iget(d_inode(child)->i_sb, ino));
962 }
963
964 static struct inode *exofs_nfs_get_inode(struct super_block *sb,
965                 u64 ino, u32 generation)
966 {
967         struct inode *inode;
968
969         inode = exofs_iget(sb, ino);
970         if (IS_ERR(inode))
971                 return ERR_CAST(inode);
972         if (generation && inode->i_generation != generation) {
973                 /* we didn't find the right inode.. */
974                 iput(inode);
975                 return ERR_PTR(-ESTALE);
976         }
977         return inode;
978 }
979
980 static struct dentry *exofs_fh_to_dentry(struct super_block *sb,
981                                 struct fid *fid, int fh_len, int fh_type)
982 {
983         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
984                                     exofs_nfs_get_inode);
985 }
986
987 static struct dentry *exofs_fh_to_parent(struct super_block *sb,
988                                 struct fid *fid, int fh_len, int fh_type)
989 {
990         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
991                                     exofs_nfs_get_inode);
992 }
993
994 static const struct export_operations exofs_export_ops = {
995         .fh_to_dentry = exofs_fh_to_dentry,
996         .fh_to_parent = exofs_fh_to_parent,
997         .get_parent = exofs_get_parent,
998 };
999
1000 /******************************************************************************
1001  * INSMOD/RMMOD
1002  *****************************************************************************/
1003
1004 /*
1005  * struct that describes this file system
1006  */
1007 static struct file_system_type exofs_type = {
1008         .owner          = THIS_MODULE,
1009         .name           = "exofs",
1010         .mount          = exofs_mount,
1011         .kill_sb        = generic_shutdown_super,
1012 };
1013 MODULE_ALIAS_FS("exofs");
1014
1015 static int __init init_exofs(void)
1016 {
1017         int err;
1018
1019         err = init_inodecache();
1020         if (err)
1021                 goto out;
1022
1023         err = register_filesystem(&exofs_type);
1024         if (err)
1025                 goto out_d;
1026
1027         /* We don't fail if sysfs creation failed */
1028         exofs_sysfs_init();
1029
1030         return 0;
1031 out_d:
1032         destroy_inodecache();
1033 out:
1034         return err;
1035 }
1036
1037 static void __exit exit_exofs(void)
1038 {
1039         exofs_sysfs_uninit();
1040         unregister_filesystem(&exofs_type);
1041         destroy_inodecache();
1042 }
1043
1044 MODULE_AUTHOR("Avishay Traeger <avishay@gmail.com>");
1045 MODULE_DESCRIPTION("exofs");
1046 MODULE_LICENSE("GPL");
1047
1048 module_init(init_exofs)
1049 module_exit(exit_exofs)