xref: /openbmc/linux/fs/nfs/nfs42proc.c (revision 2c6467d2)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2014 Anna Schumaker <Anna.Schumaker@Netapp.com>
4  */
5 #include <linux/fs.h>
6 #include <linux/sunrpc/sched.h>
7 #include <linux/nfs.h>
8 #include <linux/nfs3.h>
9 #include <linux/nfs4.h>
10 #include <linux/nfs_xdr.h>
11 #include <linux/nfs_fs.h>
12 #include "nfs4_fs.h"
13 #include "nfs42.h"
14 #include "iostat.h"
15 #include "pnfs.h"
16 #include "nfs4session.h"
17 #include "internal.h"
18 
19 #define NFSDBG_FACILITY NFSDBG_PROC
20 static int nfs42_do_offload_cancel_async(struct file *dst, nfs4_stateid *std);
21 
22 static int _nfs42_proc_fallocate(struct rpc_message *msg, struct file *filep,
23 		struct nfs_lock_context *lock, loff_t offset, loff_t len)
24 {
25 	struct inode *inode = file_inode(filep);
26 	struct nfs_server *server = NFS_SERVER(inode);
27 	struct nfs42_falloc_args args = {
28 		.falloc_fh	= NFS_FH(inode),
29 		.falloc_offset	= offset,
30 		.falloc_length	= len,
31 		.falloc_bitmask	= server->cache_consistency_bitmask,
32 	};
33 	struct nfs42_falloc_res res = {
34 		.falloc_server	= server,
35 	};
36 	int status;
37 
38 	msg->rpc_argp = &args;
39 	msg->rpc_resp = &res;
40 
41 	status = nfs4_set_rw_stateid(&args.falloc_stateid, lock->open_context,
42 			lock, FMODE_WRITE);
43 	if (status)
44 		return status;
45 
46 	res.falloc_fattr = nfs_alloc_fattr();
47 	if (!res.falloc_fattr)
48 		return -ENOMEM;
49 
50 	status = nfs4_call_sync(server->client, server, msg,
51 				&args.seq_args, &res.seq_res, 0);
52 	if (status == 0)
53 		status = nfs_post_op_update_inode(inode, res.falloc_fattr);
54 
55 	kfree(res.falloc_fattr);
56 	return status;
57 }
58 
59 static int nfs42_proc_fallocate(struct rpc_message *msg, struct file *filep,
60 				loff_t offset, loff_t len)
61 {
62 	struct nfs_server *server = NFS_SERVER(file_inode(filep));
63 	struct nfs4_exception exception = { };
64 	struct nfs_lock_context *lock;
65 	int err;
66 
67 	lock = nfs_get_lock_context(nfs_file_open_context(filep));
68 	if (IS_ERR(lock))
69 		return PTR_ERR(lock);
70 
71 	exception.inode = file_inode(filep);
72 	exception.state = lock->open_context->state;
73 
74 	do {
75 		err = _nfs42_proc_fallocate(msg, filep, lock, offset, len);
76 		if (err == -ENOTSUPP) {
77 			err = -EOPNOTSUPP;
78 			break;
79 		}
80 		err = nfs4_handle_exception(server, err, &exception);
81 	} while (exception.retry);
82 
83 	nfs_put_lock_context(lock);
84 	return err;
85 }
86 
87 int nfs42_proc_allocate(struct file *filep, loff_t offset, loff_t len)
88 {
89 	struct rpc_message msg = {
90 		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_ALLOCATE],
91 	};
92 	struct inode *inode = file_inode(filep);
93 	int err;
94 
95 	if (!nfs_server_capable(inode, NFS_CAP_ALLOCATE))
96 		return -EOPNOTSUPP;
97 
98 	inode_lock(inode);
99 
100 	err = nfs42_proc_fallocate(&msg, filep, offset, len);
101 	if (err == -EOPNOTSUPP)
102 		NFS_SERVER(inode)->caps &= ~NFS_CAP_ALLOCATE;
103 
104 	inode_unlock(inode);
105 	return err;
106 }
107 
108 int nfs42_proc_deallocate(struct file *filep, loff_t offset, loff_t len)
109 {
110 	struct rpc_message msg = {
111 		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_DEALLOCATE],
112 	};
113 	struct inode *inode = file_inode(filep);
114 	int err;
115 
116 	if (!nfs_server_capable(inode, NFS_CAP_DEALLOCATE))
117 		return -EOPNOTSUPP;
118 
119 	inode_lock(inode);
120 	err = nfs_sync_inode(inode);
121 	if (err)
122 		goto out_unlock;
123 
124 	err = nfs42_proc_fallocate(&msg, filep, offset, len);
125 	if (err == 0)
126 		truncate_pagecache_range(inode, offset, (offset + len) -1);
127 	if (err == -EOPNOTSUPP)
128 		NFS_SERVER(inode)->caps &= ~NFS_CAP_DEALLOCATE;
129 out_unlock:
130 	inode_unlock(inode);
131 	return err;
132 }
133 
134 static int handle_async_copy(struct nfs42_copy_res *res,
135 			     struct nfs_server *server,
136 			     struct file *src,
137 			     struct file *dst,
138 			     nfs4_stateid *src_stateid)
139 {
140 	struct nfs4_copy_state *copy, *tmp_copy;
141 	int status = NFS4_OK;
142 	bool found_pending = false;
143 	struct nfs_open_context *ctx = nfs_file_open_context(dst);
144 
145 	copy = kzalloc(sizeof(struct nfs4_copy_state), GFP_NOFS);
146 	if (!copy)
147 		return -ENOMEM;
148 
149 	spin_lock(&server->nfs_client->cl_lock);
150 	list_for_each_entry(tmp_copy, &server->nfs_client->pending_cb_stateids,
151 				copies) {
152 		if (memcmp(&res->write_res.stateid, &tmp_copy->stateid,
153 				NFS4_STATEID_SIZE))
154 			continue;
155 		found_pending = true;
156 		list_del(&tmp_copy->copies);
157 		break;
158 	}
159 	if (found_pending) {
160 		spin_unlock(&server->nfs_client->cl_lock);
161 		kfree(copy);
162 		copy = tmp_copy;
163 		goto out;
164 	}
165 
166 	memcpy(&copy->stateid, &res->write_res.stateid, NFS4_STATEID_SIZE);
167 	init_completion(&copy->completion);
168 	copy->parent_state = ctx->state;
169 
170 	list_add_tail(&copy->copies, &server->ss_copies);
171 	spin_unlock(&server->nfs_client->cl_lock);
172 
173 	status = wait_for_completion_interruptible(&copy->completion);
174 	spin_lock(&server->nfs_client->cl_lock);
175 	list_del_init(&copy->copies);
176 	spin_unlock(&server->nfs_client->cl_lock);
177 	if (status == -ERESTARTSYS) {
178 		goto out_cancel;
179 	} else if (copy->flags) {
180 		status = -EAGAIN;
181 		goto out_cancel;
182 	}
183 out:
184 	res->write_res.count = copy->count;
185 	memcpy(&res->write_res.verifier, &copy->verf, sizeof(copy->verf));
186 	status = -copy->error;
187 
188 	kfree(copy);
189 	return status;
190 out_cancel:
191 	nfs42_do_offload_cancel_async(dst, &copy->stateid);
192 	kfree(copy);
193 	return status;
194 }
195 
196 static int process_copy_commit(struct file *dst, loff_t pos_dst,
197 			       struct nfs42_copy_res *res)
198 {
199 	struct nfs_commitres cres;
200 	int status = -ENOMEM;
201 
202 	cres.verf = kzalloc(sizeof(struct nfs_writeverf), GFP_NOFS);
203 	if (!cres.verf)
204 		goto out;
205 
206 	status = nfs4_proc_commit(dst, pos_dst, res->write_res.count, &cres);
207 	if (status)
208 		goto out_free;
209 	if (nfs_write_verifier_cmp(&res->write_res.verifier.verifier,
210 				    &cres.verf->verifier)) {
211 		dprintk("commit verf differs from copy verf\n");
212 		status = -EAGAIN;
213 	}
214 out_free:
215 	kfree(cres.verf);
216 out:
217 	return status;
218 }
219 
220 static ssize_t _nfs42_proc_copy(struct file *src,
221 				struct nfs_lock_context *src_lock,
222 				struct file *dst,
223 				struct nfs_lock_context *dst_lock,
224 				struct nfs42_copy_args *args,
225 				struct nfs42_copy_res *res)
226 {
227 	struct rpc_message msg = {
228 		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_COPY],
229 		.rpc_argp = args,
230 		.rpc_resp = res,
231 	};
232 	struct inode *dst_inode = file_inode(dst);
233 	struct nfs_server *server = NFS_SERVER(dst_inode);
234 	loff_t pos_src = args->src_pos;
235 	loff_t pos_dst = args->dst_pos;
236 	size_t count = args->count;
237 	ssize_t status;
238 
239 	status = nfs4_set_rw_stateid(&args->src_stateid, src_lock->open_context,
240 				     src_lock, FMODE_READ);
241 	if (status)
242 		return status;
243 
244 	status = nfs_filemap_write_and_wait_range(file_inode(src)->i_mapping,
245 			pos_src, pos_src + (loff_t)count - 1);
246 	if (status)
247 		return status;
248 
249 	status = nfs4_set_rw_stateid(&args->dst_stateid, dst_lock->open_context,
250 				     dst_lock, FMODE_WRITE);
251 	if (status)
252 		return status;
253 
254 	status = nfs_sync_inode(dst_inode);
255 	if (status)
256 		return status;
257 
258 	res->commit_res.verf = NULL;
259 	if (args->sync) {
260 		res->commit_res.verf =
261 			kzalloc(sizeof(struct nfs_writeverf), GFP_NOFS);
262 		if (!res->commit_res.verf)
263 			return -ENOMEM;
264 	}
265 	set_bit(NFS_CLNT_DST_SSC_COPY_STATE,
266 		&dst_lock->open_context->state->flags);
267 
268 	status = nfs4_call_sync(server->client, server, &msg,
269 				&args->seq_args, &res->seq_res, 0);
270 	if (status == -ENOTSUPP)
271 		server->caps &= ~NFS_CAP_COPY;
272 	if (status)
273 		goto out;
274 
275 	if (args->sync &&
276 		nfs_write_verifier_cmp(&res->write_res.verifier.verifier,
277 				    &res->commit_res.verf->verifier)) {
278 		status = -EAGAIN;
279 		goto out;
280 	}
281 
282 	if (!res->synchronous) {
283 		status = handle_async_copy(res, server, src, dst,
284 				&args->src_stateid);
285 		if (status)
286 			return status;
287 	}
288 
289 	if ((!res->synchronous || !args->sync) &&
290 			res->write_res.verifier.committed != NFS_FILE_SYNC) {
291 		status = process_copy_commit(dst, pos_dst, res);
292 		if (status)
293 			return status;
294 	}
295 
296 	truncate_pagecache_range(dst_inode, pos_dst,
297 				 pos_dst + res->write_res.count);
298 
299 	status = res->write_res.count;
300 out:
301 	if (args->sync)
302 		kfree(res->commit_res.verf);
303 	return status;
304 }
305 
306 ssize_t nfs42_proc_copy(struct file *src, loff_t pos_src,
307 			struct file *dst, loff_t pos_dst,
308 			size_t count)
309 {
310 	struct nfs_server *server = NFS_SERVER(file_inode(dst));
311 	struct nfs_lock_context *src_lock;
312 	struct nfs_lock_context *dst_lock;
313 	struct nfs42_copy_args args = {
314 		.src_fh		= NFS_FH(file_inode(src)),
315 		.src_pos	= pos_src,
316 		.dst_fh		= NFS_FH(file_inode(dst)),
317 		.dst_pos	= pos_dst,
318 		.count		= count,
319 		.sync		= false,
320 	};
321 	struct nfs42_copy_res res;
322 	struct nfs4_exception src_exception = {
323 		.inode		= file_inode(src),
324 		.stateid	= &args.src_stateid,
325 	};
326 	struct nfs4_exception dst_exception = {
327 		.inode		= file_inode(dst),
328 		.stateid	= &args.dst_stateid,
329 	};
330 	ssize_t err, err2;
331 
332 	if (!nfs_server_capable(file_inode(dst), NFS_CAP_COPY))
333 		return -EOPNOTSUPP;
334 
335 	src_lock = nfs_get_lock_context(nfs_file_open_context(src));
336 	if (IS_ERR(src_lock))
337 		return PTR_ERR(src_lock);
338 
339 	src_exception.state = src_lock->open_context->state;
340 
341 	dst_lock = nfs_get_lock_context(nfs_file_open_context(dst));
342 	if (IS_ERR(dst_lock)) {
343 		err = PTR_ERR(dst_lock);
344 		goto out_put_src_lock;
345 	}
346 
347 	dst_exception.state = dst_lock->open_context->state;
348 
349 	do {
350 		inode_lock(file_inode(dst));
351 		err = _nfs42_proc_copy(src, src_lock,
352 				dst, dst_lock,
353 				&args, &res);
354 		inode_unlock(file_inode(dst));
355 
356 		if (err >= 0)
357 			break;
358 		if (err == -ENOTSUPP) {
359 			err = -EOPNOTSUPP;
360 			break;
361 		} else if (err == -EAGAIN) {
362 			dst_exception.retry = 1;
363 			continue;
364 		} else if (err == -NFS4ERR_OFFLOAD_NO_REQS && !args.sync) {
365 			args.sync = true;
366 			dst_exception.retry = 1;
367 			continue;
368 		}
369 
370 		err2 = nfs4_handle_exception(server, err, &src_exception);
371 		err  = nfs4_handle_exception(server, err, &dst_exception);
372 		if (!err)
373 			err = err2;
374 	} while (src_exception.retry || dst_exception.retry);
375 
376 	nfs_put_lock_context(dst_lock);
377 out_put_src_lock:
378 	nfs_put_lock_context(src_lock);
379 	return err;
380 }
381 
382 struct nfs42_offloadcancel_data {
383 	struct nfs_server *seq_server;
384 	struct nfs42_offload_status_args args;
385 	struct nfs42_offload_status_res res;
386 };
387 
388 static void nfs42_offload_cancel_prepare(struct rpc_task *task, void *calldata)
389 {
390 	struct nfs42_offloadcancel_data *data = calldata;
391 
392 	nfs4_setup_sequence(data->seq_server->nfs_client,
393 				&data->args.osa_seq_args,
394 				&data->res.osr_seq_res, task);
395 }
396 
397 static void nfs42_offload_cancel_done(struct rpc_task *task, void *calldata)
398 {
399 	struct nfs42_offloadcancel_data *data = calldata;
400 
401 	nfs41_sequence_done(task, &data->res.osr_seq_res);
402 	if (task->tk_status &&
403 		nfs4_async_handle_error(task, data->seq_server, NULL,
404 			NULL) == -EAGAIN)
405 		rpc_restart_call_prepare(task);
406 }
407 
408 static void nfs42_free_offloadcancel_data(void *data)
409 {
410 	kfree(data);
411 }
412 
413 static const struct rpc_call_ops nfs42_offload_cancel_ops = {
414 	.rpc_call_prepare = nfs42_offload_cancel_prepare,
415 	.rpc_call_done = nfs42_offload_cancel_done,
416 	.rpc_release = nfs42_free_offloadcancel_data,
417 };
418 
419 static int nfs42_do_offload_cancel_async(struct file *dst,
420 					 nfs4_stateid *stateid)
421 {
422 	struct nfs_server *dst_server = NFS_SERVER(file_inode(dst));
423 	struct nfs42_offloadcancel_data *data = NULL;
424 	struct nfs_open_context *ctx = nfs_file_open_context(dst);
425 	struct rpc_task *task;
426 	struct rpc_message msg = {
427 		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_OFFLOAD_CANCEL],
428 		.rpc_cred = ctx->cred,
429 	};
430 	struct rpc_task_setup task_setup_data = {
431 		.rpc_client = dst_server->client,
432 		.rpc_message = &msg,
433 		.callback_ops = &nfs42_offload_cancel_ops,
434 		.workqueue = nfsiod_workqueue,
435 		.flags = RPC_TASK_ASYNC,
436 	};
437 	int status;
438 
439 	if (!(dst_server->caps & NFS_CAP_OFFLOAD_CANCEL))
440 		return -EOPNOTSUPP;
441 
442 	data = kzalloc(sizeof(struct nfs42_offloadcancel_data), GFP_NOFS);
443 	if (data == NULL)
444 		return -ENOMEM;
445 
446 	data->seq_server = dst_server;
447 	data->args.osa_src_fh = NFS_FH(file_inode(dst));
448 	memcpy(&data->args.osa_stateid, stateid,
449 		sizeof(data->args.osa_stateid));
450 	msg.rpc_argp = &data->args;
451 	msg.rpc_resp = &data->res;
452 	task_setup_data.callback_data = data;
453 	nfs4_init_sequence(&data->args.osa_seq_args, &data->res.osr_seq_res,
454 			   1, 0);
455 	task = rpc_run_task(&task_setup_data);
456 	if (IS_ERR(task))
457 		return PTR_ERR(task);
458 	status = rpc_wait_for_completion_task(task);
459 	if (status == -ENOTSUPP)
460 		dst_server->caps &= ~NFS_CAP_OFFLOAD_CANCEL;
461 	rpc_put_task(task);
462 	return status;
463 }
464 
465 static loff_t _nfs42_proc_llseek(struct file *filep,
466 		struct nfs_lock_context *lock, loff_t offset, int whence)
467 {
468 	struct inode *inode = file_inode(filep);
469 	struct nfs42_seek_args args = {
470 		.sa_fh		= NFS_FH(inode),
471 		.sa_offset	= offset,
472 		.sa_what	= (whence == SEEK_HOLE) ?
473 					NFS4_CONTENT_HOLE : NFS4_CONTENT_DATA,
474 	};
475 	struct nfs42_seek_res res;
476 	struct rpc_message msg = {
477 		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SEEK],
478 		.rpc_argp = &args,
479 		.rpc_resp = &res,
480 	};
481 	struct nfs_server *server = NFS_SERVER(inode);
482 	int status;
483 
484 	if (!nfs_server_capable(inode, NFS_CAP_SEEK))
485 		return -ENOTSUPP;
486 
487 	status = nfs4_set_rw_stateid(&args.sa_stateid, lock->open_context,
488 			lock, FMODE_READ);
489 	if (status)
490 		return status;
491 
492 	status = nfs_filemap_write_and_wait_range(inode->i_mapping,
493 			offset, LLONG_MAX);
494 	if (status)
495 		return status;
496 
497 	status = nfs4_call_sync(server->client, server, &msg,
498 				&args.seq_args, &res.seq_res, 0);
499 	if (status == -ENOTSUPP)
500 		server->caps &= ~NFS_CAP_SEEK;
501 	if (status)
502 		return status;
503 
504 	return vfs_setpos(filep, res.sr_offset, inode->i_sb->s_maxbytes);
505 }
506 
507 loff_t nfs42_proc_llseek(struct file *filep, loff_t offset, int whence)
508 {
509 	struct nfs_server *server = NFS_SERVER(file_inode(filep));
510 	struct nfs4_exception exception = { };
511 	struct nfs_lock_context *lock;
512 	loff_t err;
513 
514 	lock = nfs_get_lock_context(nfs_file_open_context(filep));
515 	if (IS_ERR(lock))
516 		return PTR_ERR(lock);
517 
518 	exception.inode = file_inode(filep);
519 	exception.state = lock->open_context->state;
520 
521 	do {
522 		err = _nfs42_proc_llseek(filep, lock, offset, whence);
523 		if (err >= 0)
524 			break;
525 		if (err == -ENOTSUPP) {
526 			err = -EOPNOTSUPP;
527 			break;
528 		}
529 		err = nfs4_handle_exception(server, err, &exception);
530 	} while (exception.retry);
531 
532 	nfs_put_lock_context(lock);
533 	return err;
534 }
535 
536 
537 static void
538 nfs42_layoutstat_prepare(struct rpc_task *task, void *calldata)
539 {
540 	struct nfs42_layoutstat_data *data = calldata;
541 	struct inode *inode = data->inode;
542 	struct nfs_server *server = NFS_SERVER(inode);
543 	struct pnfs_layout_hdr *lo;
544 
545 	spin_lock(&inode->i_lock);
546 	lo = NFS_I(inode)->layout;
547 	if (!pnfs_layout_is_valid(lo)) {
548 		spin_unlock(&inode->i_lock);
549 		rpc_exit(task, 0);
550 		return;
551 	}
552 	nfs4_stateid_copy(&data->args.stateid, &lo->plh_stateid);
553 	spin_unlock(&inode->i_lock);
554 	nfs4_setup_sequence(server->nfs_client, &data->args.seq_args,
555 			    &data->res.seq_res, task);
556 }
557 
558 static void
559 nfs42_layoutstat_done(struct rpc_task *task, void *calldata)
560 {
561 	struct nfs42_layoutstat_data *data = calldata;
562 	struct inode *inode = data->inode;
563 	struct pnfs_layout_hdr *lo;
564 
565 	if (!nfs4_sequence_done(task, &data->res.seq_res))
566 		return;
567 
568 	switch (task->tk_status) {
569 	case 0:
570 		break;
571 	case -NFS4ERR_BADHANDLE:
572 	case -ESTALE:
573 		pnfs_destroy_layout(NFS_I(inode));
574 		break;
575 	case -NFS4ERR_EXPIRED:
576 	case -NFS4ERR_ADMIN_REVOKED:
577 	case -NFS4ERR_DELEG_REVOKED:
578 	case -NFS4ERR_STALE_STATEID:
579 	case -NFS4ERR_BAD_STATEID:
580 		spin_lock(&inode->i_lock);
581 		lo = NFS_I(inode)->layout;
582 		if (pnfs_layout_is_valid(lo) &&
583 		    nfs4_stateid_match(&data->args.stateid,
584 					     &lo->plh_stateid)) {
585 			LIST_HEAD(head);
586 
587 			/*
588 			 * Mark the bad layout state as invalid, then retry
589 			 * with the current stateid.
590 			 */
591 			pnfs_mark_layout_stateid_invalid(lo, &head);
592 			spin_unlock(&inode->i_lock);
593 			pnfs_free_lseg_list(&head);
594 			nfs_commit_inode(inode, 0);
595 		} else
596 			spin_unlock(&inode->i_lock);
597 		break;
598 	case -NFS4ERR_OLD_STATEID:
599 		spin_lock(&inode->i_lock);
600 		lo = NFS_I(inode)->layout;
601 		if (pnfs_layout_is_valid(lo) &&
602 		    nfs4_stateid_match_other(&data->args.stateid,
603 					&lo->plh_stateid)) {
604 			/* Do we need to delay before resending? */
605 			if (!nfs4_stateid_is_newer(&lo->plh_stateid,
606 						&data->args.stateid))
607 				rpc_delay(task, HZ);
608 			rpc_restart_call_prepare(task);
609 		}
610 		spin_unlock(&inode->i_lock);
611 		break;
612 	case -ENOTSUPP:
613 	case -EOPNOTSUPP:
614 		NFS_SERVER(inode)->caps &= ~NFS_CAP_LAYOUTSTATS;
615 	}
616 }
617 
618 static void
619 nfs42_layoutstat_release(void *calldata)
620 {
621 	struct nfs42_layoutstat_data *data = calldata;
622 	struct nfs42_layoutstat_devinfo *devinfo = data->args.devinfo;
623 	int i;
624 
625 	for (i = 0; i < data->args.num_dev; i++) {
626 		if (devinfo[i].ld_private.ops && devinfo[i].ld_private.ops->free)
627 			devinfo[i].ld_private.ops->free(&devinfo[i].ld_private);
628 	}
629 
630 	pnfs_put_layout_hdr(NFS_I(data->args.inode)->layout);
631 	smp_mb__before_atomic();
632 	clear_bit(NFS_INO_LAYOUTSTATS, &NFS_I(data->args.inode)->flags);
633 	smp_mb__after_atomic();
634 	nfs_iput_and_deactive(data->inode);
635 	kfree(data->args.devinfo);
636 	kfree(data);
637 }
638 
639 static const struct rpc_call_ops nfs42_layoutstat_ops = {
640 	.rpc_call_prepare = nfs42_layoutstat_prepare,
641 	.rpc_call_done = nfs42_layoutstat_done,
642 	.rpc_release = nfs42_layoutstat_release,
643 };
644 
645 int nfs42_proc_layoutstats_generic(struct nfs_server *server,
646 				   struct nfs42_layoutstat_data *data)
647 {
648 	struct rpc_message msg = {
649 		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_LAYOUTSTATS],
650 		.rpc_argp = &data->args,
651 		.rpc_resp = &data->res,
652 	};
653 	struct rpc_task_setup task_setup = {
654 		.rpc_client = server->client,
655 		.rpc_message = &msg,
656 		.callback_ops = &nfs42_layoutstat_ops,
657 		.callback_data = data,
658 		.flags = RPC_TASK_ASYNC,
659 	};
660 	struct rpc_task *task;
661 
662 	data->inode = nfs_igrab_and_active(data->args.inode);
663 	if (!data->inode) {
664 		nfs42_layoutstat_release(data);
665 		return -EAGAIN;
666 	}
667 	nfs4_init_sequence(&data->args.seq_args, &data->res.seq_res, 0, 0);
668 	task = rpc_run_task(&task_setup);
669 	if (IS_ERR(task))
670 		return PTR_ERR(task);
671 	rpc_put_task(task);
672 	return 0;
673 }
674 
675 static int _nfs42_proc_clone(struct rpc_message *msg, struct file *src_f,
676 		struct file *dst_f, struct nfs_lock_context *src_lock,
677 		struct nfs_lock_context *dst_lock, loff_t src_offset,
678 		loff_t dst_offset, loff_t count)
679 {
680 	struct inode *src_inode = file_inode(src_f);
681 	struct inode *dst_inode = file_inode(dst_f);
682 	struct nfs_server *server = NFS_SERVER(dst_inode);
683 	struct nfs42_clone_args args = {
684 		.src_fh = NFS_FH(src_inode),
685 		.dst_fh = NFS_FH(dst_inode),
686 		.src_offset = src_offset,
687 		.dst_offset = dst_offset,
688 		.count = count,
689 		.dst_bitmask = server->cache_consistency_bitmask,
690 	};
691 	struct nfs42_clone_res res = {
692 		.server	= server,
693 	};
694 	int status;
695 
696 	msg->rpc_argp = &args;
697 	msg->rpc_resp = &res;
698 
699 	status = nfs4_set_rw_stateid(&args.src_stateid, src_lock->open_context,
700 			src_lock, FMODE_READ);
701 	if (status)
702 		return status;
703 
704 	status = nfs4_set_rw_stateid(&args.dst_stateid, dst_lock->open_context,
705 			dst_lock, FMODE_WRITE);
706 	if (status)
707 		return status;
708 
709 	res.dst_fattr = nfs_alloc_fattr();
710 	if (!res.dst_fattr)
711 		return -ENOMEM;
712 
713 	status = nfs4_call_sync(server->client, server, msg,
714 				&args.seq_args, &res.seq_res, 0);
715 	if (status == 0)
716 		status = nfs_post_op_update_inode(dst_inode, res.dst_fattr);
717 
718 	kfree(res.dst_fattr);
719 	return status;
720 }
721 
722 int nfs42_proc_clone(struct file *src_f, struct file *dst_f,
723 		     loff_t src_offset, loff_t dst_offset, loff_t count)
724 {
725 	struct rpc_message msg = {
726 		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_CLONE],
727 	};
728 	struct inode *inode = file_inode(src_f);
729 	struct nfs_server *server = NFS_SERVER(file_inode(src_f));
730 	struct nfs_lock_context *src_lock;
731 	struct nfs_lock_context *dst_lock;
732 	struct nfs4_exception src_exception = { };
733 	struct nfs4_exception dst_exception = { };
734 	int err, err2;
735 
736 	if (!nfs_server_capable(inode, NFS_CAP_CLONE))
737 		return -EOPNOTSUPP;
738 
739 	src_lock = nfs_get_lock_context(nfs_file_open_context(src_f));
740 	if (IS_ERR(src_lock))
741 		return PTR_ERR(src_lock);
742 
743 	src_exception.inode = file_inode(src_f);
744 	src_exception.state = src_lock->open_context->state;
745 
746 	dst_lock = nfs_get_lock_context(nfs_file_open_context(dst_f));
747 	if (IS_ERR(dst_lock)) {
748 		err = PTR_ERR(dst_lock);
749 		goto out_put_src_lock;
750 	}
751 
752 	dst_exception.inode = file_inode(dst_f);
753 	dst_exception.state = dst_lock->open_context->state;
754 
755 	do {
756 		err = _nfs42_proc_clone(&msg, src_f, dst_f, src_lock, dst_lock,
757 					src_offset, dst_offset, count);
758 		if (err == -ENOTSUPP || err == -EOPNOTSUPP) {
759 			NFS_SERVER(inode)->caps &= ~NFS_CAP_CLONE;
760 			err = -EOPNOTSUPP;
761 			break;
762 		}
763 
764 		err2 = nfs4_handle_exception(server, err, &src_exception);
765 		err = nfs4_handle_exception(server, err, &dst_exception);
766 		if (!err)
767 			err = err2;
768 	} while (src_exception.retry || dst_exception.retry);
769 
770 	nfs_put_lock_context(dst_lock);
771 out_put_src_lock:
772 	nfs_put_lock_context(src_lock);
773 	return err;
774 }
775