exofs: Multi-device mirror support
[safe/jmp/linux-2.6] / fs / exofs / ios.c
1 /*
2  * Copyright (C) 2005, 2006
3  * Avishay Traeger (avishay@gmail.com)
4  * Copyright (C) 2008, 2009
5  * Boaz Harrosh <bharrosh@panasas.com>
6  *
7  * This file is part of exofs.
8  *
9  * exofs is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation.  Since it is based on ext2, and the only
12  * valid version of GPL for the Linux kernel is version 2, the only valid
13  * version of GPL for exofs is version 2.
14  *
15  * exofs is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with exofs; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
23  */
24
25 #include <scsi/scsi_device.h>
26
27 #include "exofs.h"
28
29 void exofs_make_credential(u8 cred_a[OSD_CAP_LEN], const struct osd_obj_id *obj)
30 {
31         osd_sec_init_nosec_doall_caps(cred_a, obj, false, true);
32 }
33
34 int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
35                     u64 offset, void *p, unsigned length)
36 {
37         struct osd_request *or = osd_start_request(od, GFP_KERNEL);
38 /*      struct osd_sense_info osi = {.key = 0};*/
39         int ret;
40
41         if (unlikely(!or)) {
42                 EXOFS_DBGMSG("%s: osd_start_request failed.\n", __func__);
43                 return -ENOMEM;
44         }
45         ret = osd_req_read_kern(or, obj, offset, p, length);
46         if (unlikely(ret)) {
47                 EXOFS_DBGMSG("%s: osd_req_read_kern failed.\n", __func__);
48                 goto out;
49         }
50
51         ret = osd_finalize_request(or, 0, cred, NULL);
52         if (unlikely(ret)) {
53                 EXOFS_DBGMSG("Faild to osd_finalize_request() => %d\n", ret);
54                 goto out;
55         }
56
57         ret = osd_execute_request(or);
58         if (unlikely(ret))
59                 EXOFS_DBGMSG("osd_execute_request() => %d\n", ret);
60         /* osd_req_decode_sense(or, ret); */
61
62 out:
63         osd_end_request(or);
64         return ret;
65 }
66
67 int exofs_get_io_state(struct exofs_sb_info *sbi, struct exofs_io_state** pios)
68 {
69         struct exofs_io_state *ios;
70
71         /*TODO: Maybe use kmem_cach per sbi of size
72          * exofs_io_state_size(sbi->s_numdevs)
73          */
74         ios = kzalloc(exofs_io_state_size(sbi->s_numdevs), GFP_KERNEL);
75         if (unlikely(!ios)) {
76                 *pios = NULL;
77                 return -ENOMEM;
78         }
79
80         ios->sbi = sbi;
81         ios->obj.partition = sbi->s_pid;
82         *pios = ios;
83         return 0;
84 }
85
86 void exofs_put_io_state(struct exofs_io_state *ios)
87 {
88         if (ios) {
89                 unsigned i;
90
91                 for (i = 0; i < ios->numdevs; i++) {
92                         struct exofs_per_dev_state *per_dev = &ios->per_dev[i];
93
94                         if (per_dev->or)
95                                 osd_end_request(per_dev->or);
96                         if (per_dev->bio)
97                                 bio_put(per_dev->bio);
98                 }
99
100                 kfree(ios);
101         }
102 }
103
104 static void _sync_done(struct exofs_io_state *ios, void *p)
105 {
106         struct completion *waiting = p;
107
108         complete(waiting);
109 }
110
111 static void _last_io(struct kref *kref)
112 {
113         struct exofs_io_state *ios = container_of(
114                                         kref, struct exofs_io_state, kref);
115
116         ios->done(ios, ios->private);
117 }
118
119 static void _done_io(struct osd_request *or, void *p)
120 {
121         struct exofs_io_state *ios = p;
122
123         kref_put(&ios->kref, _last_io);
124 }
125
126 static int exofs_io_execute(struct exofs_io_state *ios)
127 {
128         DECLARE_COMPLETION_ONSTACK(wait);
129         bool sync = (ios->done == NULL);
130         int i, ret;
131
132         if (sync) {
133                 ios->done = _sync_done;
134                 ios->private = &wait;
135         }
136
137         for (i = 0; i < ios->numdevs; i++) {
138                 struct osd_request *or = ios->per_dev[i].or;
139                 if (unlikely(!or))
140                         continue;
141
142                 ret = osd_finalize_request(or, 0, ios->cred, NULL);
143                 if (unlikely(ret)) {
144                         EXOFS_DBGMSG("Faild to osd_finalize_request() => %d\n",
145                                      ret);
146                         return ret;
147                 }
148         }
149
150         kref_init(&ios->kref);
151
152         for (i = 0; i < ios->numdevs; i++) {
153                 struct osd_request *or = ios->per_dev[i].or;
154                 if (unlikely(!or))
155                         continue;
156
157                 kref_get(&ios->kref);
158                 osd_execute_request_async(or, _done_io, ios);
159         }
160
161         kref_put(&ios->kref, _last_io);
162         ret = 0;
163
164         if (sync) {
165                 wait_for_completion(&wait);
166                 ret = exofs_check_io(ios, NULL);
167         }
168         return ret;
169 }
170
171 int exofs_check_io(struct exofs_io_state *ios, u64 *resid)
172 {
173         enum osd_err_priority acumulated_osd_err = 0;
174         int acumulated_lin_err = 0;
175         int i;
176
177         for (i = 0; i < ios->numdevs; i++) {
178                 struct osd_sense_info osi;
179                 int ret = osd_req_decode_sense(ios->per_dev[i].or, &osi);
180
181                 if (likely(!ret))
182                         continue;
183
184                 if (unlikely(ret == -EFAULT)) {
185                         EXOFS_DBGMSG("%s: EFAULT Need page clear\n", __func__);
186                         /*FIXME: All the pages in this device range should:
187                          *      clear_highpage(page);
188                          */
189                 }
190
191                 if (osi.osd_err_pri >= acumulated_osd_err) {
192                         acumulated_osd_err = osi.osd_err_pri;
193                         acumulated_lin_err = ret;
194                 }
195         }
196
197         /* TODO: raid specific residual calculations */
198         if (resid) {
199                 if (likely(!acumulated_lin_err))
200                         *resid = 0;
201                 else
202                         *resid = ios->length;
203         }
204
205         return acumulated_lin_err;
206 }
207
208 int exofs_sbi_create(struct exofs_io_state *ios)
209 {
210         int i, ret;
211
212         for (i = 0; i < ios->sbi->s_numdevs; i++) {
213                 struct osd_request *or;
214
215                 or = osd_start_request(ios->sbi->s_ods[i], GFP_KERNEL);
216                 if (unlikely(!or)) {
217                         EXOFS_ERR("%s: osd_start_request failed\n", __func__);
218                         ret = -ENOMEM;
219                         goto out;
220                 }
221                 ios->per_dev[i].or = or;
222                 ios->numdevs++;
223
224                 osd_req_create_object(or, &ios->obj);
225         }
226         ret = exofs_io_execute(ios);
227
228 out:
229         return ret;
230 }
231
232 int exofs_sbi_remove(struct exofs_io_state *ios)
233 {
234         int i, ret;
235
236         for (i = 0; i < ios->sbi->s_numdevs; i++) {
237                 struct osd_request *or;
238
239                 or = osd_start_request(ios->sbi->s_ods[i], GFP_KERNEL);
240                 if (unlikely(!or)) {
241                         EXOFS_ERR("%s: osd_start_request failed\n", __func__);
242                         ret = -ENOMEM;
243                         goto out;
244                 }
245                 ios->per_dev[i].or = or;
246                 ios->numdevs++;
247
248                 osd_req_remove_object(or, &ios->obj);
249         }
250         ret = exofs_io_execute(ios);
251
252 out:
253         return ret;
254 }
255
256 int exofs_sbi_write(struct exofs_io_state *ios)
257 {
258         int i, ret;
259
260         for (i = 0; i < ios->sbi->s_numdevs; i++) {
261                 struct osd_request *or;
262
263                 or = osd_start_request(ios->sbi->s_ods[i], GFP_KERNEL);
264                 if (unlikely(!or)) {
265                         EXOFS_ERR("%s: osd_start_request failed\n", __func__);
266                         ret = -ENOMEM;
267                         goto out;
268                 }
269                 ios->per_dev[i].or = or;
270                 ios->numdevs++;
271
272                 if (ios->bio) {
273                         struct bio *bio;
274
275                         if (i != 0) {
276                                 bio = bio_kmalloc(GFP_KERNEL,
277                                                   ios->bio->bi_max_vecs);
278                                 if (unlikely(!bio)) {
279                                         ret = -ENOMEM;
280                                         goto out;
281                                 }
282
283                                 __bio_clone(bio, ios->bio);
284                                 bio->bi_bdev = NULL;
285                                 bio->bi_next = NULL;
286                                 ios->per_dev[i].bio =  bio;
287                         } else {
288                                 bio = ios->bio;
289                         }
290
291                         osd_req_write(or, &ios->obj, ios->offset, bio,
292                                       ios->length);
293 /*                      EXOFS_DBGMSG("write sync=%d\n", sync);*/
294                 } else if (ios->kern_buff) {
295                         osd_req_write_kern(or, &ios->obj, ios->offset,
296                                            ios->kern_buff, ios->length);
297 /*                      EXOFS_DBGMSG("write_kern sync=%d\n", sync);*/
298                 } else {
299                         osd_req_set_attributes(or, &ios->obj);
300 /*                      EXOFS_DBGMSG("set_attributes sync=%d\n", sync);*/
301                 }
302
303                 if (ios->out_attr)
304                         osd_req_add_set_attr_list(or, ios->out_attr,
305                                                   ios->out_attr_len);
306
307                 if (ios->in_attr)
308                         osd_req_add_get_attr_list(or, ios->in_attr,
309                                                   ios->in_attr_len);
310         }
311         ret = exofs_io_execute(ios);
312
313 out:
314         return ret;
315 }
316
317 int exofs_sbi_read(struct exofs_io_state *ios)
318 {
319         int i, ret;
320
321         for (i = 0; i < 1; i++) {
322                 struct osd_request *or;
323                 unsigned first_dev = (unsigned)ios->obj.id;
324
325                 first_dev %= ios->sbi->s_numdevs;
326                 or = osd_start_request(ios->sbi->s_ods[first_dev], GFP_KERNEL);
327                 if (unlikely(!or)) {
328                         EXOFS_ERR("%s: osd_start_request failed\n", __func__);
329                         ret = -ENOMEM;
330                         goto out;
331                 }
332                 ios->per_dev[i].or = or;
333                 ios->numdevs++;
334
335                 if (ios->bio) {
336                         osd_req_read(or, &ios->obj, ios->offset, ios->bio,
337                                      ios->length);
338 /*                      EXOFS_DBGMSG("read sync=%d\n", sync);*/
339                 } else if (ios->kern_buff) {
340                         osd_req_read_kern(or, &ios->obj, ios->offset,
341                                            ios->kern_buff, ios->length);
342 /*                      EXOFS_DBGMSG("read_kern sync=%d\n", sync);*/
343                 } else {
344                         osd_req_get_attributes(or, &ios->obj);
345 /*                      EXOFS_DBGMSG("get_attributes sync=%d\n", sync);*/
346                 }
347
348                 if (ios->out_attr)
349                         osd_req_add_set_attr_list(or, ios->out_attr,
350                                                   ios->out_attr_len);
351
352                 if (ios->in_attr)
353                         osd_req_add_get_attr_list(or, ios->in_attr,
354                                                   ios->in_attr_len);
355         }
356         ret = exofs_io_execute(ios);
357
358 out:
359         return ret;
360 }
361
362 int extract_attr_from_ios(struct exofs_io_state *ios, struct osd_attr *attr)
363 {
364         struct osd_attr cur_attr = {.attr_page = 0}; /* start with zeros */
365         void *iter = NULL;
366         int nelem;
367
368         do {
369                 nelem = 1;
370                 osd_req_decode_get_attr_list(ios->per_dev[0].or,
371                                              &cur_attr, &nelem, &iter);
372                 if ((cur_attr.attr_page == attr->attr_page) &&
373                     (cur_attr.attr_id == attr->attr_id)) {
374                         attr->len = cur_attr.len;
375                         attr->val_ptr = cur_attr.val_ptr;
376                         return 0;
377                 }
378         } while (iter);
379
380         return -EIO;
381 }
382
383 int exofs_oi_truncate(struct exofs_i_info *oi, u64 size)
384 {
385         struct exofs_sb_info *sbi = oi->vfs_inode.i_sb->s_fs_info;
386         struct exofs_io_state *ios;
387         struct osd_attr attr;
388         __be64 newsize;
389         int i, ret;
390
391         if (exofs_get_io_state(sbi, &ios))
392                 return -ENOMEM;
393
394         ios->obj.id = exofs_oi_objno(oi);
395         ios->cred = oi->i_cred;
396
397         newsize = cpu_to_be64(size);
398         attr = g_attr_logical_length;
399         attr.val_ptr = &newsize;
400
401         for (i = 0; i < sbi->s_numdevs; i++) {
402                 struct osd_request *or;
403
404                 or = osd_start_request(sbi->s_ods[i], GFP_KERNEL);
405                 if (unlikely(!or)) {
406                         EXOFS_ERR("%s: osd_start_request failed\n", __func__);
407                         ret = -ENOMEM;
408                         goto out;
409                 }
410                 ios->per_dev[i].or = or;
411                 ios->numdevs++;
412
413                 osd_req_set_attributes(or, &ios->obj);
414                 osd_req_add_set_attr_list(or, &attr, 1);
415         }
416         ret = exofs_io_execute(ios);
417
418 out:
419         exofs_put_io_state(ios);
420         return ret;
421 }