77a2d026aa12b62bdc29dac2345cff0b3237e9c4
[kvmfornfv.git] / kernel / fs / nfs / flexfilelayout / flexfilelayoutdev.c
1 /*
2  * Device operations for the pnfs nfs4 file layout driver.
3  *
4  * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
5  *
6  * Tao Peng <bergwolf@primarydata.com>
7  */
8
9 #include <linux/nfs_fs.h>
10 #include <linux/vmalloc.h>
11 #include <linux/module.h>
12 #include <linux/sunrpc/addr.h>
13
14 #include "../internal.h"
15 #include "../nfs4session.h"
16 #include "flexfilelayout.h"
17
18 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
19
20 static unsigned int dataserver_timeo = NFS4_DEF_DS_TIMEO;
21 static unsigned int dataserver_retrans = NFS4_DEF_DS_RETRANS;
22
23 void nfs4_ff_layout_put_deviceid(struct nfs4_ff_layout_ds *mirror_ds)
24 {
25         if (mirror_ds)
26                 nfs4_put_deviceid_node(&mirror_ds->id_node);
27 }
28
29 void nfs4_ff_layout_free_deviceid(struct nfs4_ff_layout_ds *mirror_ds)
30 {
31         nfs4_print_deviceid(&mirror_ds->id_node.deviceid);
32         nfs4_pnfs_ds_put(mirror_ds->ds);
33         kfree_rcu(mirror_ds, id_node.rcu);
34 }
35
36 /* Decode opaque device data and construct new_ds using it */
37 struct nfs4_ff_layout_ds *
38 nfs4_ff_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
39                             gfp_t gfp_flags)
40 {
41         struct xdr_stream stream;
42         struct xdr_buf buf;
43         struct page *scratch;
44         struct list_head dsaddrs;
45         struct nfs4_pnfs_ds_addr *da;
46         struct nfs4_ff_layout_ds *new_ds = NULL;
47         struct nfs4_ff_ds_version *ds_versions = NULL;
48         u32 mp_count;
49         u32 version_count;
50         __be32 *p;
51         int i, ret = -ENOMEM;
52
53         /* set up xdr stream */
54         scratch = alloc_page(gfp_flags);
55         if (!scratch)
56                 goto out_err;
57
58         new_ds = kzalloc(sizeof(struct nfs4_ff_layout_ds), gfp_flags);
59         if (!new_ds)
60                 goto out_scratch;
61
62         nfs4_init_deviceid_node(&new_ds->id_node,
63                                 server,
64                                 &pdev->dev_id);
65         INIT_LIST_HEAD(&dsaddrs);
66
67         xdr_init_decode_pages(&stream, &buf, pdev->pages, pdev->pglen);
68         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
69
70         /* multipath count */
71         p = xdr_inline_decode(&stream, 4);
72         if (unlikely(!p))
73                 goto out_err_drain_dsaddrs;
74         mp_count = be32_to_cpup(p);
75         dprintk("%s: multipath ds count %d\n", __func__, mp_count);
76
77         for (i = 0; i < mp_count; i++) {
78                 /* multipath ds */
79                 da = nfs4_decode_mp_ds_addr(server->nfs_client->cl_net,
80                                             &stream, gfp_flags);
81                 if (da)
82                         list_add_tail(&da->da_node, &dsaddrs);
83         }
84         if (list_empty(&dsaddrs)) {
85                 dprintk("%s: no suitable DS addresses found\n",
86                         __func__);
87                 ret = -ENOMEDIUM;
88                 goto out_err_drain_dsaddrs;
89         }
90
91         /* version count */
92         p = xdr_inline_decode(&stream, 4);
93         if (unlikely(!p))
94                 goto out_err_drain_dsaddrs;
95         version_count = be32_to_cpup(p);
96         dprintk("%s: version count %d\n", __func__, version_count);
97
98         ds_versions = kzalloc(version_count * sizeof(struct nfs4_ff_ds_version),
99                               gfp_flags);
100         if (!ds_versions)
101                 goto out_scratch;
102
103         for (i = 0; i < version_count; i++) {
104                 /* 20 = version(4) + minor_version(4) + rsize(4) + wsize(4) +
105                  * tightly_coupled(4) */
106                 p = xdr_inline_decode(&stream, 20);
107                 if (unlikely(!p))
108                         goto out_err_drain_dsaddrs;
109                 ds_versions[i].version = be32_to_cpup(p++);
110                 ds_versions[i].minor_version = be32_to_cpup(p++);
111                 ds_versions[i].rsize = nfs_block_size(be32_to_cpup(p++), NULL);
112                 ds_versions[i].wsize = nfs_block_size(be32_to_cpup(p++), NULL);
113                 ds_versions[i].tightly_coupled = be32_to_cpup(p);
114
115                 if (ds_versions[i].rsize > NFS_MAX_FILE_IO_SIZE)
116                         ds_versions[i].rsize = NFS_MAX_FILE_IO_SIZE;
117                 if (ds_versions[i].wsize > NFS_MAX_FILE_IO_SIZE)
118                         ds_versions[i].wsize = NFS_MAX_FILE_IO_SIZE;
119
120                 if (ds_versions[i].version != 3 || ds_versions[i].minor_version != 0) {
121                         dprintk("%s: [%d] unsupported ds version %d-%d\n", __func__,
122                                 i, ds_versions[i].version,
123                                 ds_versions[i].minor_version);
124                         ret = -EPROTONOSUPPORT;
125                         goto out_err_drain_dsaddrs;
126                 }
127
128                 dprintk("%s: [%d] vers %u minor_ver %u rsize %u wsize %u coupled %d\n",
129                         __func__, i, ds_versions[i].version,
130                         ds_versions[i].minor_version,
131                         ds_versions[i].rsize,
132                         ds_versions[i].wsize,
133                         ds_versions[i].tightly_coupled);
134         }
135
136         new_ds->ds_versions = ds_versions;
137         new_ds->ds_versions_cnt = version_count;
138
139         new_ds->ds = nfs4_pnfs_ds_add(&dsaddrs, gfp_flags);
140         if (!new_ds->ds)
141                 goto out_err_drain_dsaddrs;
142
143         /* If DS was already in cache, free ds addrs */
144         while (!list_empty(&dsaddrs)) {
145                 da = list_first_entry(&dsaddrs,
146                                       struct nfs4_pnfs_ds_addr,
147                                       da_node);
148                 list_del_init(&da->da_node);
149                 kfree(da->da_remotestr);
150                 kfree(da);
151         }
152
153         __free_page(scratch);
154         return new_ds;
155
156 out_err_drain_dsaddrs:
157         while (!list_empty(&dsaddrs)) {
158                 da = list_first_entry(&dsaddrs, struct nfs4_pnfs_ds_addr,
159                                       da_node);
160                 list_del_init(&da->da_node);
161                 kfree(da->da_remotestr);
162                 kfree(da);
163         }
164
165         kfree(ds_versions);
166 out_scratch:
167         __free_page(scratch);
168 out_err:
169         kfree(new_ds);
170
171         dprintk("%s ERROR: returning %d\n", __func__, ret);
172         return NULL;
173 }
174
175 static u64
176 end_offset(u64 start, u64 len)
177 {
178         u64 end;
179
180         end = start + len;
181         return end >= start ? end : NFS4_MAX_UINT64;
182 }
183
184 static void extend_ds_error(struct nfs4_ff_layout_ds_err *err,
185                             u64 offset, u64 length)
186 {
187         u64 end;
188
189         end = max_t(u64, end_offset(err->offset, err->length),
190                     end_offset(offset, length));
191         err->offset = min_t(u64, err->offset, offset);
192         err->length = end - err->offset;
193 }
194
195 static bool ds_error_can_merge(struct nfs4_ff_layout_ds_err *err,  u64 offset,
196                                u64 length, int status, enum nfs_opnum4 opnum,
197                                nfs4_stateid *stateid,
198                                struct nfs4_deviceid *deviceid)
199 {
200         return err->status == status && err->opnum == opnum &&
201                nfs4_stateid_match(&err->stateid, stateid) &&
202                !memcmp(&err->deviceid, deviceid, sizeof(*deviceid)) &&
203                end_offset(err->offset, err->length) >= offset &&
204                err->offset <= end_offset(offset, length);
205 }
206
207 static bool merge_ds_error(struct nfs4_ff_layout_ds_err *old,
208                            struct nfs4_ff_layout_ds_err *new)
209 {
210         if (!ds_error_can_merge(old, new->offset, new->length, new->status,
211                                 new->opnum, &new->stateid, &new->deviceid))
212                 return false;
213
214         extend_ds_error(old, new->offset, new->length);
215         return true;
216 }
217
218 static bool
219 ff_layout_add_ds_error_locked(struct nfs4_flexfile_layout *flo,
220                               struct nfs4_ff_layout_ds_err *dserr)
221 {
222         struct nfs4_ff_layout_ds_err *err;
223
224         list_for_each_entry(err, &flo->error_list, list) {
225                 if (merge_ds_error(err, dserr)) {
226                         return true;
227                 }
228         }
229
230         list_add(&dserr->list, &flo->error_list);
231         return false;
232 }
233
234 static bool
235 ff_layout_update_ds_error(struct nfs4_flexfile_layout *flo, u64 offset,
236                           u64 length, int status, enum nfs_opnum4 opnum,
237                           nfs4_stateid *stateid, struct nfs4_deviceid *deviceid)
238 {
239         bool found = false;
240         struct nfs4_ff_layout_ds_err *err;
241
242         list_for_each_entry(err, &flo->error_list, list) {
243                 if (ds_error_can_merge(err, offset, length, status, opnum,
244                                        stateid, deviceid)) {
245                         found = true;
246                         extend_ds_error(err, offset, length);
247                         break;
248                 }
249         }
250
251         return found;
252 }
253
254 int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
255                              struct nfs4_ff_layout_mirror *mirror, u64 offset,
256                              u64 length, int status, enum nfs_opnum4 opnum,
257                              gfp_t gfp_flags)
258 {
259         struct nfs4_ff_layout_ds_err *dserr;
260         bool needfree;
261
262         if (status == 0)
263                 return 0;
264
265         if (mirror->mirror_ds == NULL)
266                 return -EINVAL;
267
268         spin_lock(&flo->generic_hdr.plh_inode->i_lock);
269         if (ff_layout_update_ds_error(flo, offset, length, status, opnum,
270                                       &mirror->stateid,
271                                       &mirror->mirror_ds->id_node.deviceid)) {
272                 spin_unlock(&flo->generic_hdr.plh_inode->i_lock);
273                 return 0;
274         }
275         spin_unlock(&flo->generic_hdr.plh_inode->i_lock);
276         dserr = kmalloc(sizeof(*dserr), gfp_flags);
277         if (!dserr)
278                 return -ENOMEM;
279
280         INIT_LIST_HEAD(&dserr->list);
281         dserr->offset = offset;
282         dserr->length = length;
283         dserr->status = status;
284         dserr->opnum = opnum;
285         nfs4_stateid_copy(&dserr->stateid, &mirror->stateid);
286         memcpy(&dserr->deviceid, &mirror->mirror_ds->id_node.deviceid,
287                NFS4_DEVICEID4_SIZE);
288
289         spin_lock(&flo->generic_hdr.plh_inode->i_lock);
290         needfree = ff_layout_add_ds_error_locked(flo, dserr);
291         spin_unlock(&flo->generic_hdr.plh_inode->i_lock);
292         if (needfree)
293                 kfree(dserr);
294
295         return 0;
296 }
297
298 /* currently we only support AUTH_NONE and AUTH_SYS */
299 static rpc_authflavor_t
300 nfs4_ff_layout_choose_authflavor(struct nfs4_ff_layout_mirror *mirror)
301 {
302         if (mirror->uid == (u32)-1)
303                 return RPC_AUTH_NULL;
304         return RPC_AUTH_UNIX;
305 }
306
307 /* fetch cred for NFSv3 DS */
308 static int ff_layout_update_mirror_cred(struct nfs4_ff_layout_mirror *mirror,
309                                       struct nfs4_pnfs_ds *ds)
310 {
311         if (ds->ds_clp && !mirror->cred &&
312             mirror->mirror_ds->ds_versions[0].version == 3) {
313                 struct rpc_auth *auth = ds->ds_clp->cl_rpcclient->cl_auth;
314                 struct rpc_cred *cred;
315                 struct auth_cred acred = {
316                         .uid = make_kuid(&init_user_ns, mirror->uid),
317                         .gid = make_kgid(&init_user_ns, mirror->gid),
318                 };
319
320                 /* AUTH_NULL ignores acred */
321                 cred = auth->au_ops->lookup_cred(auth, &acred, 0);
322                 if (IS_ERR(cred)) {
323                         dprintk("%s: lookup_cred failed with %ld\n",
324                                 __func__, PTR_ERR(cred));
325                         return PTR_ERR(cred);
326                 } else {
327                         mirror->cred = cred;
328                 }
329         }
330         return 0;
331 }
332
333 struct nfs_fh *
334 nfs4_ff_layout_select_ds_fh(struct pnfs_layout_segment *lseg, u32 mirror_idx)
335 {
336         struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, mirror_idx);
337         struct nfs_fh *fh = NULL;
338         struct nfs4_deviceid_node *devid;
339
340         if (mirror == NULL || mirror->mirror_ds == NULL ||
341             mirror->mirror_ds->ds == NULL) {
342                 printk(KERN_ERR "NFS: %s: No data server for mirror offset index %d\n",
343                         __func__, mirror_idx);
344                 if (mirror && mirror->mirror_ds) {
345                         devid = &mirror->mirror_ds->id_node;
346                         pnfs_generic_mark_devid_invalid(devid);
347                 }
348                 goto out;
349         }
350
351         /* FIXME: For now assume there is only 1 version available for the DS */
352         fh = &mirror->fh_versions[0];
353 out:
354         return fh;
355 }
356
357 /* Upon return, either ds is connected, or ds is NULL */
358 struct nfs4_pnfs_ds *
359 nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx,
360                           bool fail_return)
361 {
362         struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, ds_idx);
363         struct nfs4_pnfs_ds *ds = NULL;
364         struct nfs4_deviceid_node *devid;
365         struct inode *ino = lseg->pls_layout->plh_inode;
366         struct nfs_server *s = NFS_SERVER(ino);
367         unsigned int max_payload;
368         rpc_authflavor_t flavor;
369
370         if (mirror == NULL || mirror->mirror_ds == NULL ||
371             mirror->mirror_ds->ds == NULL) {
372                 printk(KERN_ERR "NFS: %s: No data server for offset index %d\n",
373                         __func__, ds_idx);
374                 if (mirror && mirror->mirror_ds) {
375                         devid = &mirror->mirror_ds->id_node;
376                         pnfs_generic_mark_devid_invalid(devid);
377                 }
378                 goto out;
379         }
380
381         devid = &mirror->mirror_ds->id_node;
382         if (ff_layout_test_devid_unavailable(devid))
383                 goto out;
384
385         ds = mirror->mirror_ds->ds;
386         /* matching smp_wmb() in _nfs4_pnfs_v3/4_ds_connect */
387         smp_rmb();
388         if (ds->ds_clp)
389                 goto out;
390
391         flavor = nfs4_ff_layout_choose_authflavor(mirror);
392
393         /* FIXME: For now we assume the server sent only one version of NFS
394          * to use for the DS.
395          */
396         nfs4_pnfs_ds_connect(s, ds, devid, dataserver_timeo,
397                              dataserver_retrans,
398                              mirror->mirror_ds->ds_versions[0].version,
399                              mirror->mirror_ds->ds_versions[0].minor_version,
400                              flavor);
401
402         /* connect success, check rsize/wsize limit */
403         if (ds->ds_clp) {
404                 max_payload =
405                         nfs_block_size(rpc_max_payload(ds->ds_clp->cl_rpcclient),
406                                        NULL);
407                 if (mirror->mirror_ds->ds_versions[0].rsize > max_payload)
408                         mirror->mirror_ds->ds_versions[0].rsize = max_payload;
409                 if (mirror->mirror_ds->ds_versions[0].wsize > max_payload)
410                         mirror->mirror_ds->ds_versions[0].wsize = max_payload;
411         } else {
412                 ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
413                                          mirror, lseg->pls_range.offset,
414                                          lseg->pls_range.length, NFS4ERR_NXIO,
415                                          OP_ILLEGAL, GFP_NOIO);
416                 if (fail_return) {
417                         pnfs_error_mark_layout_for_return(ino, lseg);
418                         if (ff_layout_has_available_ds(lseg))
419                                 pnfs_set_retry_layoutget(lseg->pls_layout);
420                         else
421                                 pnfs_clear_retry_layoutget(lseg->pls_layout);
422
423                 } else {
424                         if (ff_layout_has_available_ds(lseg))
425                                 set_bit(NFS_LAYOUT_RETURN_BEFORE_CLOSE,
426                                         &lseg->pls_layout->plh_flags);
427                         else {
428                                 pnfs_error_mark_layout_for_return(ino, lseg);
429                                 pnfs_clear_retry_layoutget(lseg->pls_layout);
430                         }
431                 }
432         }
433
434         if (ff_layout_update_mirror_cred(mirror, ds))
435                 ds = NULL;
436 out:
437         return ds;
438 }
439
440 struct rpc_cred *
441 ff_layout_get_ds_cred(struct pnfs_layout_segment *lseg, u32 ds_idx,
442                       struct rpc_cred *mdscred)
443 {
444         struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, ds_idx);
445         struct rpc_cred *cred = ERR_PTR(-EINVAL);
446
447         if (!nfs4_ff_layout_prepare_ds(lseg, ds_idx, true))
448                 goto out;
449
450         if (mirror && mirror->cred)
451                 cred = mirror->cred;
452         else
453                 cred = mdscred;
454 out:
455         return cred;
456 }
457
458 /**
459 * Find or create a DS rpc client with th MDS server rpc client auth flavor
460 * in the nfs_client cl_ds_clients list.
461 */
462 struct rpc_clnt *
463 nfs4_ff_find_or_create_ds_client(struct pnfs_layout_segment *lseg, u32 ds_idx,
464                                  struct nfs_client *ds_clp, struct inode *inode)
465 {
466         struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, ds_idx);
467
468         switch (mirror->mirror_ds->ds_versions[0].version) {
469         case 3:
470                 /* For NFSv3 DS, flavor is set when creating DS connections */
471                 return ds_clp->cl_rpcclient;
472         case 4:
473                 return nfs4_find_or_create_ds_client(ds_clp, inode);
474         default:
475                 BUG();
476         }
477 }
478
479 static bool is_range_intersecting(u64 offset1, u64 length1,
480                                   u64 offset2, u64 length2)
481 {
482         u64 end1 = end_offset(offset1, length1);
483         u64 end2 = end_offset(offset2, length2);
484
485         return (end1 == NFS4_MAX_UINT64 || end1 > offset2) &&
486                (end2 == NFS4_MAX_UINT64 || end2 > offset1);
487 }
488
489 /* called with inode i_lock held */
490 int ff_layout_encode_ds_ioerr(struct nfs4_flexfile_layout *flo,
491                               struct xdr_stream *xdr, int *count,
492                               const struct pnfs_layout_range *range)
493 {
494         struct nfs4_ff_layout_ds_err *err, *n;
495         __be32 *p;
496
497         list_for_each_entry_safe(err, n, &flo->error_list, list) {
498                 if (!is_range_intersecting(err->offset, err->length,
499                                            range->offset, range->length))
500                         continue;
501                 /* offset(8) + length(8) + stateid(NFS4_STATEID_SIZE)
502                  * + deviceid(NFS4_DEVICEID4_SIZE) + status(4) + opnum(4)
503                  */
504                 p = xdr_reserve_space(xdr,
505                                 24 + NFS4_STATEID_SIZE + NFS4_DEVICEID4_SIZE);
506                 if (unlikely(!p))
507                         return -ENOBUFS;
508                 p = xdr_encode_hyper(p, err->offset);
509                 p = xdr_encode_hyper(p, err->length);
510                 p = xdr_encode_opaque_fixed(p, &err->stateid,
511                                             NFS4_STATEID_SIZE);
512                 p = xdr_encode_opaque_fixed(p, &err->deviceid,
513                                             NFS4_DEVICEID4_SIZE);
514                 *p++ = cpu_to_be32(err->status);
515                 *p++ = cpu_to_be32(err->opnum);
516                 *count += 1;
517                 list_del(&err->list);
518                 dprintk("%s: offset %llu length %llu status %d op %d count %d\n",
519                         __func__, err->offset, err->length, err->status,
520                         err->opnum, *count);
521                 kfree(err);
522         }
523
524         return 0;
525 }
526
527 bool ff_layout_has_available_ds(struct pnfs_layout_segment *lseg)
528 {
529         struct nfs4_ff_layout_mirror *mirror;
530         struct nfs4_deviceid_node *devid;
531         int idx;
532
533         for (idx = 0; idx < FF_LAYOUT_MIRROR_COUNT(lseg); idx++) {
534                 mirror = FF_LAYOUT_COMP(lseg, idx);
535                 if (mirror && mirror->mirror_ds) {
536                         devid = &mirror->mirror_ds->id_node;
537                         if (!ff_layout_test_devid_unavailable(devid))
538                                 return true;
539                 }
540         }
541
542         return false;
543 }
544
545 module_param(dataserver_retrans, uint, 0644);
546 MODULE_PARM_DESC(dataserver_retrans, "The  number of times the NFSv4.1 client "
547                         "retries a request before it attempts further "
548                         " recovery  action.");
549 module_param(dataserver_timeo, uint, 0644);
550 MODULE_PARM_DESC(dataserver_timeo, "The time (in tenths of a second) the "
551                         "NFSv4.1  client  waits for a response from a "
552                         " data server before it retries an NFS request.");