xref: /openbmc/linux/fs/nfs/callback_proc.c (revision 4800cd83)
1 /*
2  * linux/fs/nfs/callback_proc.c
3  *
4  * Copyright (C) 2004 Trond Myklebust
5  *
6  * NFSv4 callback procedures
7  */
8 #include <linux/nfs4.h>
9 #include <linux/nfs_fs.h>
10 #include <linux/slab.h>
11 #include "nfs4_fs.h"
12 #include "callback.h"
13 #include "delegation.h"
14 #include "internal.h"
15 #include "pnfs.h"
16 
17 #ifdef NFS_DEBUG
18 #define NFSDBG_FACILITY NFSDBG_CALLBACK
19 #endif
20 
21 __be32 nfs4_callback_getattr(struct cb_getattrargs *args,
22 			     struct cb_getattrres *res,
23 			     struct cb_process_state *cps)
24 {
25 	struct nfs_delegation *delegation;
26 	struct nfs_inode *nfsi;
27 	struct inode *inode;
28 
29 	res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
30 	if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
31 		goto out;
32 
33 	res->bitmap[0] = res->bitmap[1] = 0;
34 	res->status = htonl(NFS4ERR_BADHANDLE);
35 
36 	dprintk("NFS: GETATTR callback request from %s\n",
37 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
38 
39 	inode = nfs_delegation_find_inode(cps->clp, &args->fh);
40 	if (inode == NULL)
41 		goto out;
42 	nfsi = NFS_I(inode);
43 	rcu_read_lock();
44 	delegation = rcu_dereference(nfsi->delegation);
45 	if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
46 		goto out_iput;
47 	res->size = i_size_read(inode);
48 	res->change_attr = delegation->change_attr;
49 	if (nfsi->npages != 0)
50 		res->change_attr++;
51 	res->ctime = inode->i_ctime;
52 	res->mtime = inode->i_mtime;
53 	res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) &
54 		args->bitmap[0];
55 	res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) &
56 		args->bitmap[1];
57 	res->status = 0;
58 out_iput:
59 	rcu_read_unlock();
60 	iput(inode);
61 out:
62 	dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
63 	return res->status;
64 }
65 
66 __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
67 			    struct cb_process_state *cps)
68 {
69 	struct inode *inode;
70 	__be32 res;
71 
72 	res = htonl(NFS4ERR_OP_NOT_IN_SESSION);
73 	if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
74 		goto out;
75 
76 	dprintk("NFS: RECALL callback request from %s\n",
77 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
78 
79 	res = htonl(NFS4ERR_BADHANDLE);
80 	inode = nfs_delegation_find_inode(cps->clp, &args->fh);
81 	if (inode == NULL)
82 		goto out;
83 	/* Set up a helper thread to actually return the delegation */
84 	switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
85 	case 0:
86 		res = 0;
87 		break;
88 	case -ENOENT:
89 		if (res != 0)
90 			res = htonl(NFS4ERR_BAD_STATEID);
91 		break;
92 	default:
93 		res = htonl(NFS4ERR_RESOURCE);
94 	}
95 	iput(inode);
96 out:
97 	dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
98 	return res;
99 }
100 
101 int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation, const nfs4_stateid *stateid)
102 {
103 	if (delegation == NULL || memcmp(delegation->stateid.data, stateid->data,
104 					 sizeof(delegation->stateid.data)) != 0)
105 		return 0;
106 	return 1;
107 }
108 
109 #if defined(CONFIG_NFS_V4_1)
110 
111 static u32 initiate_file_draining(struct nfs_client *clp,
112 				  struct cb_layoutrecallargs *args)
113 {
114 	struct pnfs_layout_hdr *lo;
115 	struct inode *ino;
116 	bool found = false;
117 	u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
118 	LIST_HEAD(free_me_list);
119 
120 	spin_lock(&clp->cl_lock);
121 	list_for_each_entry(lo, &clp->cl_layouts, plh_layouts) {
122 		if (nfs_compare_fh(&args->cbl_fh,
123 				   &NFS_I(lo->plh_inode)->fh))
124 			continue;
125 		ino = igrab(lo->plh_inode);
126 		if (!ino)
127 			continue;
128 		found = true;
129 		/* Without this, layout can be freed as soon
130 		 * as we release cl_lock.
131 		 */
132 		get_layout_hdr(lo);
133 		break;
134 	}
135 	spin_unlock(&clp->cl_lock);
136 	if (!found)
137 		return NFS4ERR_NOMATCHING_LAYOUT;
138 
139 	spin_lock(&ino->i_lock);
140 	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
141 	    mark_matching_lsegs_invalid(lo, &free_me_list,
142 					args->cbl_range.iomode))
143 		rv = NFS4ERR_DELAY;
144 	else
145 		rv = NFS4ERR_NOMATCHING_LAYOUT;
146 	pnfs_set_layout_stateid(lo, &args->cbl_stateid, true);
147 	spin_unlock(&ino->i_lock);
148 	pnfs_free_lseg_list(&free_me_list);
149 	put_layout_hdr(lo);
150 	iput(ino);
151 	return rv;
152 }
153 
154 static u32 initiate_bulk_draining(struct nfs_client *clp,
155 				  struct cb_layoutrecallargs *args)
156 {
157 	struct pnfs_layout_hdr *lo;
158 	struct inode *ino;
159 	u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
160 	struct pnfs_layout_hdr *tmp;
161 	LIST_HEAD(recall_list);
162 	LIST_HEAD(free_me_list);
163 	struct pnfs_layout_range range = {
164 		.iomode = IOMODE_ANY,
165 		.offset = 0,
166 		.length = NFS4_MAX_UINT64,
167 	};
168 
169 	spin_lock(&clp->cl_lock);
170 	list_for_each_entry(lo, &clp->cl_layouts, plh_layouts) {
171 		if ((args->cbl_recall_type == RETURN_FSID) &&
172 		    memcmp(&NFS_SERVER(lo->plh_inode)->fsid,
173 			   &args->cbl_fsid, sizeof(struct nfs_fsid)))
174 			continue;
175 		if (!igrab(lo->plh_inode))
176 			continue;
177 		get_layout_hdr(lo);
178 		BUG_ON(!list_empty(&lo->plh_bulk_recall));
179 		list_add(&lo->plh_bulk_recall, &recall_list);
180 	}
181 	spin_unlock(&clp->cl_lock);
182 	list_for_each_entry_safe(lo, tmp,
183 				 &recall_list, plh_bulk_recall) {
184 		ino = lo->plh_inode;
185 		spin_lock(&ino->i_lock);
186 		set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
187 		if (mark_matching_lsegs_invalid(lo, &free_me_list, range.iomode))
188 			rv = NFS4ERR_DELAY;
189 		list_del_init(&lo->plh_bulk_recall);
190 		spin_unlock(&ino->i_lock);
191 		put_layout_hdr(lo);
192 		iput(ino);
193 	}
194 	pnfs_free_lseg_list(&free_me_list);
195 	return rv;
196 }
197 
198 static u32 do_callback_layoutrecall(struct nfs_client *clp,
199 				    struct cb_layoutrecallargs *args)
200 {
201 	u32 res = NFS4ERR_DELAY;
202 
203 	dprintk("%s enter, type=%i\n", __func__, args->cbl_recall_type);
204 	if (test_and_set_bit(NFS4CLNT_LAYOUTRECALL, &clp->cl_state))
205 		goto out;
206 	if (args->cbl_recall_type == RETURN_FILE)
207 		res = initiate_file_draining(clp, args);
208 	else
209 		res = initiate_bulk_draining(clp, args);
210 	clear_bit(NFS4CLNT_LAYOUTRECALL, &clp->cl_state);
211 out:
212 	dprintk("%s returning %i\n", __func__, res);
213 	return res;
214 
215 }
216 
217 __be32 nfs4_callback_layoutrecall(struct cb_layoutrecallargs *args,
218 				  void *dummy, struct cb_process_state *cps)
219 {
220 	u32 res;
221 
222 	dprintk("%s: -->\n", __func__);
223 
224 	if (cps->clp)
225 		res = do_callback_layoutrecall(cps->clp, args);
226 	else
227 		res = NFS4ERR_OP_NOT_IN_SESSION;
228 
229 	dprintk("%s: exit with status = %d\n", __func__, res);
230 	return cpu_to_be32(res);
231 }
232 
233 static void pnfs_recall_all_layouts(struct nfs_client *clp)
234 {
235 	struct cb_layoutrecallargs args;
236 
237 	/* Pretend we got a CB_LAYOUTRECALL(ALL) */
238 	memset(&args, 0, sizeof(args));
239 	args.cbl_recall_type = RETURN_ALL;
240 	/* FIXME we ignore errors, what should we do? */
241 	do_callback_layoutrecall(clp, &args);
242 }
243 
244 int nfs41_validate_delegation_stateid(struct nfs_delegation *delegation, const nfs4_stateid *stateid)
245 {
246 	if (delegation == NULL)
247 		return 0;
248 
249 	if (stateid->stateid.seqid != 0)
250 		return 0;
251 	if (memcmp(&delegation->stateid.stateid.other,
252 		   &stateid->stateid.other,
253 		   NFS4_STATEID_OTHER_SIZE))
254 		return 0;
255 
256 	return 1;
257 }
258 
259 /*
260  * Validate the sequenceID sent by the server.
261  * Return success if the sequenceID is one more than what we last saw on
262  * this slot, accounting for wraparound.  Increments the slot's sequence.
263  *
264  * We don't yet implement a duplicate request cache, instead we set the
265  * back channel ca_maxresponsesize_cached to zero. This is OK for now
266  * since we only currently implement idempotent callbacks anyway.
267  *
268  * We have a single slot backchannel at this time, so we don't bother
269  * checking the used_slots bit array on the table.  The lower layer guarantees
270  * a single outstanding callback request at a time.
271  */
272 static __be32
273 validate_seqid(struct nfs4_slot_table *tbl, struct cb_sequenceargs * args)
274 {
275 	struct nfs4_slot *slot;
276 
277 	dprintk("%s enter. slotid %d seqid %d\n",
278 		__func__, args->csa_slotid, args->csa_sequenceid);
279 
280 	if (args->csa_slotid > NFS41_BC_MAX_CALLBACKS)
281 		return htonl(NFS4ERR_BADSLOT);
282 
283 	slot = tbl->slots + args->csa_slotid;
284 	dprintk("%s slot table seqid: %d\n", __func__, slot->seq_nr);
285 
286 	/* Normal */
287 	if (likely(args->csa_sequenceid == slot->seq_nr + 1)) {
288 		slot->seq_nr++;
289 		return htonl(NFS4_OK);
290 	}
291 
292 	/* Replay */
293 	if (args->csa_sequenceid == slot->seq_nr) {
294 		dprintk("%s seqid %d is a replay\n",
295 			__func__, args->csa_sequenceid);
296 		/* Signal process_op to set this error on next op */
297 		if (args->csa_cachethis == 0)
298 			return htonl(NFS4ERR_RETRY_UNCACHED_REP);
299 
300 		/* The ca_maxresponsesize_cached is 0 with no DRC */
301 		else if (args->csa_cachethis == 1)
302 			return htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
303 	}
304 
305 	/* Wraparound */
306 	if (args->csa_sequenceid == 1 && (slot->seq_nr + 1) == 0) {
307 		slot->seq_nr = 1;
308 		return htonl(NFS4_OK);
309 	}
310 
311 	/* Misordered request */
312 	return htonl(NFS4ERR_SEQ_MISORDERED);
313 }
314 
315 /*
316  * For each referring call triple, check the session's slot table for
317  * a match.  If the slot is in use and the sequence numbers match, the
318  * client is still waiting for a response to the original request.
319  */
320 static bool referring_call_exists(struct nfs_client *clp,
321 				  uint32_t nrclists,
322 				  struct referring_call_list *rclists)
323 {
324 	bool status = 0;
325 	int i, j;
326 	struct nfs4_session *session;
327 	struct nfs4_slot_table *tbl;
328 	struct referring_call_list *rclist;
329 	struct referring_call *ref;
330 
331 	/*
332 	 * XXX When client trunking is implemented, this becomes
333 	 * a session lookup from within the loop
334 	 */
335 	session = clp->cl_session;
336 	tbl = &session->fc_slot_table;
337 
338 	for (i = 0; i < nrclists; i++) {
339 		rclist = &rclists[i];
340 		if (memcmp(session->sess_id.data,
341 			   rclist->rcl_sessionid.data,
342 			   NFS4_MAX_SESSIONID_LEN) != 0)
343 			continue;
344 
345 		for (j = 0; j < rclist->rcl_nrefcalls; j++) {
346 			ref = &rclist->rcl_refcalls[j];
347 
348 			dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u "
349 				"slotid %u\n", __func__,
350 				((u32 *)&rclist->rcl_sessionid.data)[0],
351 				((u32 *)&rclist->rcl_sessionid.data)[1],
352 				((u32 *)&rclist->rcl_sessionid.data)[2],
353 				((u32 *)&rclist->rcl_sessionid.data)[3],
354 				ref->rc_sequenceid, ref->rc_slotid);
355 
356 			spin_lock(&tbl->slot_tbl_lock);
357 			status = (test_bit(ref->rc_slotid, tbl->used_slots) &&
358 				  tbl->slots[ref->rc_slotid].seq_nr ==
359 					ref->rc_sequenceid);
360 			spin_unlock(&tbl->slot_tbl_lock);
361 			if (status)
362 				goto out;
363 		}
364 	}
365 
366 out:
367 	return status;
368 }
369 
370 __be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
371 			      struct cb_sequenceres *res,
372 			      struct cb_process_state *cps)
373 {
374 	struct nfs_client *clp;
375 	int i;
376 	__be32 status = htonl(NFS4ERR_BADSESSION);
377 
378 	cps->clp = NULL;
379 
380 	clp = nfs4_find_client_sessionid(args->csa_addr, &args->csa_sessionid);
381 	if (clp == NULL)
382 		goto out;
383 
384 	/* state manager is resetting the session */
385 	if (test_bit(NFS4_SESSION_DRAINING, &clp->cl_session->session_state)) {
386 		status = NFS4ERR_DELAY;
387 		goto out;
388 	}
389 
390 	status = validate_seqid(&clp->cl_session->bc_slot_table, args);
391 	if (status)
392 		goto out;
393 
394 	/*
395 	 * Check for pending referring calls.  If a match is found, a
396 	 * related callback was received before the response to the original
397 	 * call.
398 	 */
399 	if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) {
400 		status = htonl(NFS4ERR_DELAY);
401 		goto out;
402 	}
403 
404 	memcpy(&res->csr_sessionid, &args->csa_sessionid,
405 	       sizeof(res->csr_sessionid));
406 	res->csr_sequenceid = args->csa_sequenceid;
407 	res->csr_slotid = args->csa_slotid;
408 	res->csr_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
409 	res->csr_target_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
410 	nfs4_cb_take_slot(clp);
411 
412 out:
413 	cps->clp = clp; /* put in nfs4_callback_compound */
414 	for (i = 0; i < args->csa_nrclists; i++)
415 		kfree(args->csa_rclists[i].rcl_refcalls);
416 	kfree(args->csa_rclists);
417 
418 	if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) {
419 		cps->drc_status = status;
420 		status = 0;
421 	} else
422 		res->csr_status = status;
423 
424 	dprintk("%s: exit with status = %d res->csr_status %d\n", __func__,
425 		ntohl(status), ntohl(res->csr_status));
426 	return status;
427 }
428 
429 static bool
430 validate_bitmap_values(unsigned long mask)
431 {
432 	return (mask & ~RCA4_TYPE_MASK_ALL) == 0;
433 }
434 
435 __be32 nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy,
436 			       struct cb_process_state *cps)
437 {
438 	__be32 status;
439 	fmode_t flags = 0;
440 
441 	status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
442 	if (!cps->clp) /* set in cb_sequence */
443 		goto out;
444 
445 	dprintk("NFS: RECALL_ANY callback request from %s\n",
446 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
447 
448 	status = cpu_to_be32(NFS4ERR_INVAL);
449 	if (!validate_bitmap_values(args->craa_type_mask))
450 		goto out;
451 
452 	status = cpu_to_be32(NFS4_OK);
453 	if (test_bit(RCA4_TYPE_MASK_RDATA_DLG, (const unsigned long *)
454 		     &args->craa_type_mask))
455 		flags = FMODE_READ;
456 	if (test_bit(RCA4_TYPE_MASK_WDATA_DLG, (const unsigned long *)
457 		     &args->craa_type_mask))
458 		flags |= FMODE_WRITE;
459 	if (test_bit(RCA4_TYPE_MASK_FILE_LAYOUT, (const unsigned long *)
460 		     &args->craa_type_mask))
461 		pnfs_recall_all_layouts(cps->clp);
462 	if (flags)
463 		nfs_expire_all_delegation_types(cps->clp, flags);
464 out:
465 	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
466 	return status;
467 }
468 
469 /* Reduce the fore channel's max_slots to the target value */
470 __be32 nfs4_callback_recallslot(struct cb_recallslotargs *args, void *dummy,
471 				struct cb_process_state *cps)
472 {
473 	struct nfs4_slot_table *fc_tbl;
474 	__be32 status;
475 
476 	status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
477 	if (!cps->clp) /* set in cb_sequence */
478 		goto out;
479 
480 	dprintk("NFS: CB_RECALL_SLOT request from %s target max slots %d\n",
481 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR),
482 		args->crsa_target_max_slots);
483 
484 	fc_tbl = &cps->clp->cl_session->fc_slot_table;
485 
486 	status = htonl(NFS4ERR_BAD_HIGH_SLOT);
487 	if (args->crsa_target_max_slots > fc_tbl->max_slots ||
488 	    args->crsa_target_max_slots < 1)
489 		goto out;
490 
491 	status = htonl(NFS4_OK);
492 	if (args->crsa_target_max_slots == fc_tbl->max_slots)
493 		goto out;
494 
495 	fc_tbl->target_max_slots = args->crsa_target_max_slots;
496 	nfs41_handle_recall_slot(cps->clp);
497 out:
498 	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
499 	return status;
500 }
501 #endif /* CONFIG_NFS_V4_1 */
502