1 // SPDX-License-Identifier: GPL-2.0
3 * linux/fs/nfs/callback_proc.c
5 * Copyright (C) 2004 Trond Myklebust
7 * NFSv4 callback procedures
9 #include <linux/nfs4.h>
10 #include <linux/nfs_fs.h>
11 #include <linux/slab.h>
12 #include <linux/rcupdate.h>
15 #include "delegation.h"
18 #include "nfs4session.h"
19 #include "nfs4trace.h"
21 #define NFSDBG_FACILITY NFSDBG_CALLBACK
23 __be32 nfs4_callback_getattr(void *argp, void *resp,
24 struct cb_process_state *cps)
26 struct cb_getattrargs *args = argp;
27 struct cb_getattrres *res = resp;
28 struct nfs_delegation *delegation;
29 struct nfs_inode *nfsi;
32 res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
33 if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
36 res->bitmap[0] = res->bitmap[1] = 0;
37 res->status = htonl(NFS4ERR_BADHANDLE);
39 dprintk_rcu("NFS: GETATTR callback request from %s\n",
40 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
42 inode = nfs_delegation_find_inode(cps->clp, &args->fh);
44 if (inode == ERR_PTR(-EAGAIN))
45 res->status = htonl(NFS4ERR_DELAY);
46 trace_nfs4_cb_getattr(cps->clp, &args->fh, NULL,
52 delegation = rcu_dereference(nfsi->delegation);
53 if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
55 res->size = i_size_read(inode);
56 res->change_attr = delegation->change_attr;
57 if (nfs_have_writebacks(inode))
59 res->ctime = timespec64_to_timespec(inode->i_ctime);
60 res->mtime = timespec64_to_timespec(inode->i_mtime);
61 res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) &
63 res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) &
68 trace_nfs4_cb_getattr(cps->clp, &args->fh, inode, -ntohl(res->status));
71 dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
75 __be32 nfs4_callback_recall(void *argp, void *resp,
76 struct cb_process_state *cps)
78 struct cb_recallargs *args = argp;
82 res = htonl(NFS4ERR_OP_NOT_IN_SESSION);
83 if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
86 dprintk_rcu("NFS: RECALL callback request from %s\n",
87 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
89 res = htonl(NFS4ERR_BADHANDLE);
90 inode = nfs_delegation_find_inode(cps->clp, &args->fh);
92 if (inode == ERR_PTR(-EAGAIN))
93 res = htonl(NFS4ERR_DELAY);
94 trace_nfs4_cb_recall(cps->clp, &args->fh, NULL,
95 &args->stateid, -ntohl(res));
98 /* Set up a helper thread to actually return the delegation */
99 switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
104 res = htonl(NFS4ERR_BAD_STATEID);
107 res = htonl(NFS4ERR_RESOURCE);
109 trace_nfs4_cb_recall(cps->clp, &args->fh, inode,
110 &args->stateid, -ntohl(res));
113 dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
117 #if defined(CONFIG_NFS_V4_1)
120 * Lookup a layout inode by stateid
122 * Note: returns a refcount on the inode and superblock
124 static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp,
125 const nfs4_stateid *stateid)
127 struct nfs_server *server;
129 struct pnfs_layout_hdr *lo;
131 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
132 list_for_each_entry(lo, &server->layouts, plh_layouts) {
133 if (stateid != NULL &&
134 !nfs4_stateid_match_other(stateid, &lo->plh_stateid))
136 inode = igrab(lo->plh_inode);
138 return ERR_PTR(-EAGAIN);
139 if (!nfs_sb_active(inode->i_sb)) {
141 spin_unlock(&clp->cl_lock);
143 spin_lock(&clp->cl_lock);
145 return ERR_PTR(-EAGAIN);
151 return ERR_PTR(-ENOENT);
155 * Lookup a layout inode by filehandle.
157 * Note: returns a refcount on the inode and superblock
160 static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp,
161 const struct nfs_fh *fh)
163 struct nfs_server *server;
164 struct nfs_inode *nfsi;
166 struct pnfs_layout_hdr *lo;
168 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
169 list_for_each_entry(lo, &server->layouts, plh_layouts) {
170 nfsi = NFS_I(lo->plh_inode);
171 if (nfs_compare_fh(fh, &nfsi->fh))
173 if (nfsi->layout != lo)
175 inode = igrab(lo->plh_inode);
177 return ERR_PTR(-EAGAIN);
178 if (!nfs_sb_active(inode->i_sb)) {
180 spin_unlock(&clp->cl_lock);
182 spin_lock(&clp->cl_lock);
184 return ERR_PTR(-EAGAIN);
190 return ERR_PTR(-ENOENT);
193 static struct inode *nfs_layout_find_inode(struct nfs_client *clp,
194 const struct nfs_fh *fh,
195 const nfs4_stateid *stateid)
199 spin_lock(&clp->cl_lock);
201 inode = nfs_layout_find_inode_by_stateid(clp, stateid);
202 if (inode == ERR_PTR(-ENOENT))
203 inode = nfs_layout_find_inode_by_fh(clp, fh);
205 spin_unlock(&clp->cl_lock);
211 * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing)
213 static u32 pnfs_check_callback_stateid(struct pnfs_layout_hdr *lo,
214 const nfs4_stateid *new)
218 /* Is the stateid not initialised? */
219 if (!pnfs_layout_is_valid(lo))
220 return NFS4ERR_NOMATCHING_LAYOUT;
222 /* Mismatched stateid? */
223 if (!nfs4_stateid_match_other(&lo->plh_stateid, new))
224 return NFS4ERR_BAD_STATEID;
226 newseq = be32_to_cpu(new->seqid);
227 /* Are we already in a layout recall situation? */
228 if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) &&
229 lo->plh_return_seq != 0) {
230 if (newseq < lo->plh_return_seq)
231 return NFS4ERR_OLD_STATEID;
232 if (newseq > lo->plh_return_seq)
233 return NFS4ERR_DELAY;
237 /* Check that the stateid matches what we think it should be. */
238 oldseq = be32_to_cpu(lo->plh_stateid.seqid);
239 if (newseq > oldseq + 1)
240 return NFS4ERR_DELAY;
242 if (newseq <= oldseq)
243 return NFS4ERR_OLD_STATEID;
248 static u32 initiate_file_draining(struct nfs_client *clp,
249 struct cb_layoutrecallargs *args)
252 struct pnfs_layout_hdr *lo;
253 u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
254 LIST_HEAD(free_me_list);
256 ino = nfs_layout_find_inode(clp, &args->cbl_fh, &args->cbl_stateid);
258 if (ino == ERR_PTR(-EAGAIN))
263 pnfs_layoutcommit_inode(ino, false);
266 spin_lock(&ino->i_lock);
267 lo = NFS_I(ino)->layout;
269 spin_unlock(&ino->i_lock);
272 pnfs_get_layout_hdr(lo);
273 rv = pnfs_check_callback_stateid(lo, &args->cbl_stateid);
278 * Enforce RFC5661 Section 12.5.5.2.1.5 (Bulk Recall and Return)
280 if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
285 pnfs_set_layout_stateid(lo, &args->cbl_stateid, true);
286 switch (pnfs_mark_matching_lsegs_return(lo, &free_me_list,
288 be32_to_cpu(args->cbl_stateid.seqid))) {
291 /* There are layout segments that need to be returned */
295 /* Embrace your forgetfulness! */
296 rv = NFS4ERR_NOMATCHING_LAYOUT;
298 if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
299 NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo,
304 spin_unlock(&ino->i_lock);
305 pnfs_free_lseg_list(&free_me_list);
306 /* Free all lsegs that are attached to commit buckets */
307 nfs_commit_inode(ino, 0);
308 pnfs_put_layout_hdr(lo);
310 nfs_iput_and_deactive(ino);
312 trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino,
313 &args->cbl_stateid, -rv);
317 static u32 initiate_bulk_draining(struct nfs_client *clp,
318 struct cb_layoutrecallargs *args)
322 if (args->cbl_recall_type == RETURN_FSID)
323 stat = pnfs_destroy_layouts_byfsid(clp, &args->cbl_fsid, true);
325 stat = pnfs_destroy_layouts_byclid(clp, true);
327 return NFS4ERR_DELAY;
328 return NFS4ERR_NOMATCHING_LAYOUT;
331 static u32 do_callback_layoutrecall(struct nfs_client *clp,
332 struct cb_layoutrecallargs *args)
334 if (args->cbl_recall_type == RETURN_FILE)
335 return initiate_file_draining(clp, args);
336 return initiate_bulk_draining(clp, args);
339 __be32 nfs4_callback_layoutrecall(void *argp, void *resp,
340 struct cb_process_state *cps)
342 struct cb_layoutrecallargs *args = argp;
343 u32 res = NFS4ERR_OP_NOT_IN_SESSION;
346 res = do_callback_layoutrecall(cps->clp, args);
347 return cpu_to_be32(res);
350 static void pnfs_recall_all_layouts(struct nfs_client *clp)
352 struct cb_layoutrecallargs args;
354 /* Pretend we got a CB_LAYOUTRECALL(ALL) */
355 memset(&args, 0, sizeof(args));
356 args.cbl_recall_type = RETURN_ALL;
357 /* FIXME we ignore errors, what should we do? */
358 do_callback_layoutrecall(clp, &args);
361 __be32 nfs4_callback_devicenotify(void *argp, void *resp,
362 struct cb_process_state *cps)
364 struct cb_devicenotifyargs *args = argp;
367 struct nfs_client *clp = cps->clp;
368 struct nfs_server *server = NULL;
371 res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
375 for (i = 0; i < args->ndevs; i++) {
376 struct cb_devicenotifyitem *dev = &args->devs[i];
379 server->pnfs_curr_ld->id != dev->cbd_layout_type) {
381 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
382 if (server->pnfs_curr_ld &&
383 server->pnfs_curr_ld->id == dev->cbd_layout_type) {
392 nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id);
401 * Validate the sequenceID sent by the server.
402 * Return success if the sequenceID is one more than what we last saw on
403 * this slot, accounting for wraparound. Increments the slot's sequence.
405 * We don't yet implement a duplicate request cache, instead we set the
406 * back channel ca_maxresponsesize_cached to zero. This is OK for now
407 * since we only currently implement idempotent callbacks anyway.
409 * We have a single slot backchannel at this time, so we don't bother
410 * checking the used_slots bit array on the table. The lower layer guarantees
411 * a single outstanding callback request at a time.
414 validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot,
415 const struct cb_sequenceargs * args)
417 if (args->csa_slotid > tbl->server_highest_slotid)
418 return htonl(NFS4ERR_BADSLOT);
421 if (args->csa_sequenceid == slot->seq_nr) {
422 if (nfs4_test_locked_slot(tbl, slot->slot_nr))
423 return htonl(NFS4ERR_DELAY);
424 /* Signal process_op to set this error on next op */
425 if (args->csa_cachethis == 0)
426 return htonl(NFS4ERR_RETRY_UNCACHED_REP);
428 /* Liar! We never allowed you to set csa_cachethis != 0 */
429 return htonl(NFS4ERR_SEQ_FALSE_RETRY);
432 /* Note: wraparound relies on seq_nr being of type u32 */
433 if (likely(args->csa_sequenceid == slot->seq_nr + 1))
434 return htonl(NFS4_OK);
436 /* Misordered request */
437 return htonl(NFS4ERR_SEQ_MISORDERED);
441 * For each referring call triple, check the session's slot table for
442 * a match. If the slot is in use and the sequence numbers match, the
443 * client is still waiting for a response to the original request.
445 static int referring_call_exists(struct nfs_client *clp,
447 struct referring_call_list *rclists,
454 struct nfs4_session *session;
455 struct nfs4_slot_table *tbl;
456 struct referring_call_list *rclist;
457 struct referring_call *ref;
460 * XXX When client trunking is implemented, this becomes
461 * a session lookup from within the loop
463 session = clp->cl_session;
464 tbl = &session->fc_slot_table;
466 for (i = 0; i < nrclists; i++) {
467 rclist = &rclists[i];
468 if (memcmp(session->sess_id.data,
469 rclist->rcl_sessionid.data,
470 NFS4_MAX_SESSIONID_LEN) != 0)
473 for (j = 0; j < rclist->rcl_nrefcalls; j++) {
474 ref = &rclist->rcl_refcalls[j];
476 status = nfs4_slot_wait_on_seqid(tbl, ref->rc_slotid,
477 ref->rc_sequenceid, HZ >> 1) < 0;
488 __be32 nfs4_callback_sequence(void *argp, void *resp,
489 struct cb_process_state *cps)
491 struct cb_sequenceargs *args = argp;
492 struct cb_sequenceres *res = resp;
493 struct nfs4_slot_table *tbl;
494 struct nfs4_slot *slot;
495 struct nfs_client *clp;
497 __be32 status = htonl(NFS4ERR_BADSESSION);
499 clp = nfs4_find_client_sessionid(cps->net, args->csa_addr,
500 &args->csa_sessionid, cps->minorversion);
504 if (!(clp->cl_session->flags & SESSION4_BACK_CHAN))
507 tbl = &clp->cl_session->bc_slot_table;
509 /* Set up res before grabbing the spinlock */
510 memcpy(&res->csr_sessionid, &args->csa_sessionid,
511 sizeof(res->csr_sessionid));
512 res->csr_sequenceid = args->csa_sequenceid;
513 res->csr_slotid = args->csa_slotid;
515 spin_lock(&tbl->slot_tbl_lock);
516 /* state manager is resetting the session */
517 if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
518 status = htonl(NFS4ERR_DELAY);
519 /* Return NFS4ERR_BADSESSION if we're draining the session
520 * in order to reset it.
522 if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
523 status = htonl(NFS4ERR_BADSESSION);
527 status = htonl(NFS4ERR_BADSLOT);
528 slot = nfs4_lookup_slot(tbl, args->csa_slotid);
532 res->csr_highestslotid = tbl->server_highest_slotid;
533 res->csr_target_highestslotid = tbl->target_highest_slotid;
535 status = validate_seqid(tbl, slot, args);
538 if (!nfs4_try_to_lock_slot(tbl, slot)) {
539 status = htonl(NFS4ERR_DELAY);
544 /* The ca_maxresponsesize_cached is 0 with no DRC */
545 if (args->csa_cachethis != 0) {
546 status = htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
551 * Check for pending referring calls. If a match is found, a
552 * related callback was received before the response to the original
555 if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists,
556 &tbl->slot_tbl_lock) < 0) {
557 status = htonl(NFS4ERR_DELAY);
563 * If CB_SEQUENCE returns an error, then the state of the slot
564 * (sequence ID, cached reply) MUST NOT change.
566 slot->seq_nr = args->csa_sequenceid;
568 spin_unlock(&tbl->slot_tbl_lock);
571 cps->clp = clp; /* put in nfs4_callback_compound */
572 for (i = 0; i < args->csa_nrclists; i++)
573 kfree(args->csa_rclists[i].rcl_refcalls);
574 kfree(args->csa_rclists);
576 if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) {
577 cps->drc_status = status;
580 res->csr_status = status;
582 trace_nfs4_cb_sequence(args, res, status);
587 validate_bitmap_values(unsigned int mask)
589 return (mask & ~RCA4_TYPE_MASK_ALL) == 0;
592 __be32 nfs4_callback_recallany(void *argp, void *resp,
593 struct cb_process_state *cps)
595 struct cb_recallanyargs *args = argp;
599 status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
600 if (!cps->clp) /* set in cb_sequence */
603 dprintk_rcu("NFS: RECALL_ANY callback request from %s\n",
604 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
606 status = cpu_to_be32(NFS4ERR_INVAL);
607 if (!validate_bitmap_values(args->craa_type_mask))
610 status = cpu_to_be32(NFS4_OK);
611 if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_RDATA_DLG))
613 if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_WDATA_DLG))
614 flags |= FMODE_WRITE;
616 nfs_expire_unused_delegation_types(cps->clp, flags);
618 if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_FILE_LAYOUT))
619 pnfs_recall_all_layouts(cps->clp);
621 dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
625 /* Reduce the fore channel's max_slots to the target value */
626 __be32 nfs4_callback_recallslot(void *argp, void *resp,
627 struct cb_process_state *cps)
629 struct cb_recallslotargs *args = argp;
630 struct nfs4_slot_table *fc_tbl;
633 status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
634 if (!cps->clp) /* set in cb_sequence */
637 dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n",
638 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR),
639 args->crsa_target_highest_slotid);
641 fc_tbl = &cps->clp->cl_session->fc_slot_table;
643 status = htonl(NFS4_OK);
645 nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid);
646 nfs41_notify_server(cps->clp);
648 dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
652 __be32 nfs4_callback_notify_lock(void *argp, void *resp,
653 struct cb_process_state *cps)
655 struct cb_notify_lock_args *args = argp;
657 if (!cps->clp) /* set in cb_sequence */
658 return htonl(NFS4ERR_OP_NOT_IN_SESSION);
660 dprintk_rcu("NFS: CB_NOTIFY_LOCK request from %s\n",
661 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
663 /* Don't wake anybody if the string looked bogus */
664 if (args->cbnl_valid)
665 __wake_up(&cps->clp->cl_lock_waitq, TASK_NORMAL, 0, args);
667 return htonl(NFS4_OK);
669 #endif /* CONFIG_NFS_V4_1 */
670 #ifdef CONFIG_NFS_V4_2
671 static void nfs4_copy_cb_args(struct nfs4_copy_state *cp_state,
672 struct cb_offloadargs *args)
674 cp_state->count = args->wr_count;
675 cp_state->error = args->error;
677 cp_state->verf.committed = args->wr_writeverf.committed;
678 memcpy(&cp_state->verf.verifier.data[0],
679 &args->wr_writeverf.verifier.data[0],
684 __be32 nfs4_callback_offload(void *data, void *dummy,
685 struct cb_process_state *cps)
687 struct cb_offloadargs *args = data;
688 struct nfs_server *server;
689 struct nfs4_copy_state *copy;
692 spin_lock(&cps->clp->cl_lock);
694 list_for_each_entry_rcu(server, &cps->clp->cl_superblocks,
696 list_for_each_entry(copy, &server->ss_copies, copies) {
697 if (memcmp(args->coa_stateid.other,
699 sizeof(args->coa_stateid.other)))
701 nfs4_copy_cb_args(copy, args);
702 complete(©->completion);
710 copy = kzalloc(sizeof(struct nfs4_copy_state), GFP_NOFS);
712 spin_unlock(&cps->clp->cl_lock);
713 return htonl(NFS4ERR_SERVERFAULT);
715 memcpy(©->stateid, &args->coa_stateid, NFS4_STATEID_SIZE);
716 nfs4_copy_cb_args(copy, args);
717 list_add_tail(©->copies, &cps->clp->pending_cb_stateids);
719 spin_unlock(&cps->clp->cl_lock);
723 #endif /* CONFIG_NFS_V4_2 */