// SPDX-License-Identifier: GPL-2.0 /* * linux/fs/nfs/callback_proc.c * * Copyright (C) 2004 Trond Myklebust * * NFSv4 callback procedures */ #include #include #include #include #include "nfs4_fs.h" #include "callback.h" #include "delegation.h" #include "internal.h" #include "pnfs.h" #include "nfs4session.h" #include "nfs4trace.h" #define NFSDBG_FACILITY NFSDBG_CALLBACK __be32 nfs4_callback_getattr(void *argp, void *resp, struct cb_process_state *cps) { struct cb_getattrargs *args = argp; struct cb_getattrres *res = resp; struct nfs_delegation *delegation; struct nfs_inode *nfsi; struct inode *inode; res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION); if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */ goto out; res->bitmap[0] = res->bitmap[1] = 0; res->status = htonl(NFS4ERR_BADHANDLE); dprintk_rcu("NFS: GETATTR callback request from %s\n", rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); inode = nfs_delegation_find_inode(cps->clp, &args->fh); if (inode == NULL) { trace_nfs4_cb_getattr(cps->clp, &args->fh, NULL, -ntohl(res->status)); goto out; } nfsi = NFS_I(inode); rcu_read_lock(); delegation = rcu_dereference(nfsi->delegation); if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0) goto out_iput; res->size = i_size_read(inode); res->change_attr = delegation->change_attr; if (nfs_have_writebacks(inode)) res->change_attr++; res->ctime = inode->i_ctime; res->mtime = inode->i_mtime; res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) & args->bitmap[0]; res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) & args->bitmap[1]; res->status = 0; out_iput: rcu_read_unlock(); trace_nfs4_cb_getattr(cps->clp, &args->fh, inode, -ntohl(res->status)); iput(inode); out: dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status)); return res->status; } __be32 nfs4_callback_recall(void *argp, void *resp, struct cb_process_state *cps) { struct cb_recallargs *args = argp; struct inode *inode; __be32 res; res = htonl(NFS4ERR_OP_NOT_IN_SESSION); if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */ goto out; dprintk_rcu("NFS: RECALL callback request from %s\n", rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); res = htonl(NFS4ERR_BADHANDLE); inode = nfs_delegation_find_inode(cps->clp, &args->fh); if (inode == NULL) { trace_nfs4_cb_recall(cps->clp, &args->fh, NULL, &args->stateid, -ntohl(res)); goto out; } /* Set up a helper thread to actually return the delegation */ switch (nfs_async_inode_return_delegation(inode, &args->stateid)) { case 0: res = 0; break; case -ENOENT: res = htonl(NFS4ERR_BAD_STATEID); break; default: res = htonl(NFS4ERR_RESOURCE); } trace_nfs4_cb_recall(cps->clp, &args->fh, inode, &args->stateid, -ntohl(res)); iput(inode); out: dprintk("%s: exit with status = %d\n", __func__, ntohl(res)); return res; } #if defined(CONFIG_NFS_V4_1) /* * Lookup a layout inode by stateid * * Note: returns a refcount on the inode and superblock */ static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp, const nfs4_stateid *stateid) { struct nfs_server *server; struct inode *inode; struct pnfs_layout_hdr *lo; restart: list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { list_for_each_entry(lo, &server->layouts, plh_layouts) { if (!pnfs_layout_is_valid(lo)) continue; if (stateid != NULL && !nfs4_stateid_match_other(stateid, &lo->plh_stateid)) continue; inode = igrab(lo->plh_inode); if (!inode) continue; if (!nfs_sb_active(inode->i_sb)) { rcu_read_unlock(); spin_unlock(&clp->cl_lock); iput(inode); spin_lock(&clp->cl_lock); rcu_read_lock(); goto restart; } return inode; } } return NULL; } /* * Lookup a layout inode by filehandle. * * Note: returns a refcount on the inode and superblock * */ static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp, const struct nfs_fh *fh) { struct nfs_server *server; struct nfs_inode *nfsi; struct inode *inode; struct pnfs_layout_hdr *lo; restart: list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { list_for_each_entry(lo, &server->layouts, plh_layouts) { nfsi = NFS_I(lo->plh_inode); if (nfs_compare_fh(fh, &nfsi->fh)) continue; if (nfsi->layout != lo) continue; inode = igrab(lo->plh_inode); if (!inode) continue; if (!nfs_sb_active(inode->i_sb)) { rcu_read_unlock(); spin_unlock(&clp->cl_lock); iput(inode); spin_lock(&clp->cl_lock); rcu_read_lock(); goto restart; } return inode; } } return NULL; } static struct inode *nfs_layout_find_inode(struct nfs_client *clp, const struct nfs_fh *fh, const nfs4_stateid *stateid) { struct inode *inode; spin_lock(&clp->cl_lock); rcu_read_lock(); inode = nfs_layout_find_inode_by_stateid(clp, stateid); if (!inode) inode = nfs_layout_find_inode_by_fh(clp, fh); rcu_read_unlock(); spin_unlock(&clp->cl_lock); return inode; } /* * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing) */ static u32 pnfs_check_callback_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new) { u32 oldseq, newseq; /* Is the stateid not initialised? */ if (!pnfs_layout_is_valid(lo)) return NFS4ERR_NOMATCHING_LAYOUT; /* Mismatched stateid? */ if (!nfs4_stateid_match_other(&lo->plh_stateid, new)) return NFS4ERR_BAD_STATEID; newseq = be32_to_cpu(new->seqid); /* Are we already in a layout recall situation? */ if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) && lo->plh_return_seq != 0) { if (newseq < lo->plh_return_seq) return NFS4ERR_OLD_STATEID; if (newseq > lo->plh_return_seq) return NFS4ERR_DELAY; goto out; } /* Check that the stateid matches what we think it should be. */ oldseq = be32_to_cpu(lo->plh_stateid.seqid); if (newseq > oldseq + 1) return NFS4ERR_DELAY; /* Crazy server! */ if (newseq <= oldseq) return NFS4ERR_OLD_STATEID; out: return NFS_OK; } static u32 initiate_file_draining(struct nfs_client *clp, struct cb_layoutrecallargs *args) { struct inode *ino; struct pnfs_layout_hdr *lo; u32 rv = NFS4ERR_NOMATCHING_LAYOUT; LIST_HEAD(free_me_list); ino = nfs_layout_find_inode(clp, &args->cbl_fh, &args->cbl_stateid); if (!ino) goto out; pnfs_layoutcommit_inode(ino, false); spin_lock(&ino->i_lock); lo = NFS_I(ino)->layout; if (!lo) { spin_unlock(&ino->i_lock); goto out; } pnfs_get_layout_hdr(lo); rv = pnfs_check_callback_stateid(lo, &args->cbl_stateid); if (rv != NFS_OK) goto unlock; pnfs_set_layout_stateid(lo, &args->cbl_stateid, true); /* * Enforce RFC5661 Section 12.5.5.2.1.5 (Bulk Recall and Return) */ if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) { rv = NFS4ERR_DELAY; goto unlock; } if (pnfs_mark_matching_lsegs_return(lo, &free_me_list, &args->cbl_range, be32_to_cpu(args->cbl_stateid.seqid))) { rv = NFS4_OK; goto unlock; } /* Embrace your forgetfulness! */ rv = NFS4ERR_NOMATCHING_LAYOUT; if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) { NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, &args->cbl_range); } unlock: spin_unlock(&ino->i_lock); pnfs_free_lseg_list(&free_me_list); /* Free all lsegs that are attached to commit buckets */ nfs_commit_inode(ino, 0); pnfs_put_layout_hdr(lo); out: trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino, &args->cbl_stateid, -rv); nfs_iput_and_deactive(ino); return rv; } static u32 initiate_bulk_draining(struct nfs_client *clp, struct cb_layoutrecallargs *args) { int stat; if (args->cbl_recall_type == RETURN_FSID) stat = pnfs_destroy_layouts_byfsid(clp, &args->cbl_fsid, true); else stat = pnfs_destroy_layouts_byclid(clp, true); if (stat != 0) return NFS4ERR_DELAY; return NFS4ERR_NOMATCHING_LAYOUT; } static u32 do_callback_layoutrecall(struct nfs_client *clp, struct cb_layoutrecallargs *args) { if (args->cbl_recall_type == RETURN_FILE) return initiate_file_draining(clp, args); return initiate_bulk_draining(clp, args); } __be32 nfs4_callback_layoutrecall(void *argp, void *resp, struct cb_process_state *cps) { struct cb_layoutrecallargs *args = argp; u32 res = NFS4ERR_OP_NOT_IN_SESSION; if (cps->clp) res = do_callback_layoutrecall(cps->clp, args); return cpu_to_be32(res); } static void pnfs_recall_all_layouts(struct nfs_client *clp) { struct cb_layoutrecallargs args; /* Pretend we got a CB_LAYOUTRECALL(ALL) */ memset(&args, 0, sizeof(args)); args.cbl_recall_type = RETURN_ALL; /* FIXME we ignore errors, what should we do? */ do_callback_layoutrecall(clp, &args); } __be32 nfs4_callback_devicenotify(void *argp, void *resp, struct cb_process_state *cps) { struct cb_devicenotifyargs *args = argp; int i; __be32 res = 0; struct nfs_client *clp = cps->clp; struct nfs_server *server = NULL; if (!clp) { res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION); goto out; } for (i = 0; i < args->ndevs; i++) { struct cb_devicenotifyitem *dev = &args->devs[i]; if (!server || server->pnfs_curr_ld->id != dev->cbd_layout_type) { rcu_read_lock(); list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) if (server->pnfs_curr_ld && server->pnfs_curr_ld->id == dev->cbd_layout_type) { rcu_read_unlock(); goto found; } rcu_read_unlock(); continue; } found: nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id); } out: kfree(args->devs); return res; } /* * Validate the sequenceID sent by the server. * Return success if the sequenceID is one more than what we last saw on * this slot, accounting for wraparound. Increments the slot's sequence. * * We don't yet implement a duplicate request cache, instead we set the * back channel ca_maxresponsesize_cached to zero. This is OK for now * since we only currently implement idempotent callbacks anyway. * * We have a single slot backchannel at this time, so we don't bother * checking the used_slots bit array on the table. The lower layer guarantees * a single outstanding callback request at a time. */ static __be32 validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot, const struct cb_sequenceargs * args) { if (args->csa_slotid > tbl->server_highest_slotid) return htonl(NFS4ERR_BADSLOT); /* Replay */ if (args->csa_sequenceid == slot->seq_nr) { if (nfs4_test_locked_slot(tbl, slot->slot_nr)) return htonl(NFS4ERR_DELAY); /* Signal process_op to set this error on next op */ if (args->csa_cachethis == 0) return htonl(NFS4ERR_RETRY_UNCACHED_REP); /* Liar! We never allowed you to set csa_cachethis != 0 */ return htonl(NFS4ERR_SEQ_FALSE_RETRY); } /* Note: wraparound relies on seq_nr being of type u32 */ if (likely(args->csa_sequenceid == slot->seq_nr + 1)) return htonl(NFS4_OK); /* Misordered request */ return htonl(NFS4ERR_SEQ_MISORDERED); } /* * For each referring call triple, check the session's slot table for * a match. If the slot is in use and the sequence numbers match, the * client is still waiting for a response to the original request. */ static int referring_call_exists(struct nfs_client *clp, uint32_t nrclists, struct referring_call_list *rclists, spinlock_t *lock) __releases(lock) __acquires(lock) { int status = 0; int i, j; struct nfs4_session *session; struct nfs4_slot_table *tbl; struct referring_call_list *rclist; struct referring_call *ref; /* * XXX When client trunking is implemented, this becomes * a session lookup from within the loop */ session = clp->cl_session; tbl = &session->fc_slot_table; for (i = 0; i < nrclists; i++) { rclist = &rclists[i]; if (memcmp(session->sess_id.data, rclist->rcl_sessionid.data, NFS4_MAX_SESSIONID_LEN) != 0) continue; for (j = 0; j < rclist->rcl_nrefcalls; j++) { ref = &rclist->rcl_refcalls[j]; spin_unlock(lock); status = nfs4_slot_wait_on_seqid(tbl, ref->rc_slotid, ref->rc_sequenceid, HZ >> 1) < 0; spin_lock(lock); if (status) goto out; } } out: return status; } __be32 nfs4_callback_sequence(void *argp, void *resp, struct cb_process_state *cps) { struct cb_sequenceargs *args = argp; struct cb_sequenceres *res = resp; struct nfs4_slot_table *tbl; struct nfs4_slot *slot; struct nfs_client *clp; int i; __be32 status = htonl(NFS4ERR_BADSESSION); clp = nfs4_find_client_sessionid(cps->net, args->csa_addr, &args->csa_sessionid, cps->minorversion); if (clp == NULL) goto out; if (!(clp->cl_session->flags & SESSION4_BACK_CHAN)) goto out; tbl = &clp->cl_session->bc_slot_table; /* Set up res before grabbing the spinlock */ memcpy(&res->csr_sessionid, &args->csa_sessionid, sizeof(res->csr_sessionid)); res->csr_sequenceid = args->csa_sequenceid; res->csr_slotid = args->csa_slotid; spin_lock(&tbl->slot_tbl_lock); /* state manager is resetting the session */ if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) { status = htonl(NFS4ERR_DELAY); /* Return NFS4ERR_BADSESSION if we're draining the session * in order to reset it. */ if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) status = htonl(NFS4ERR_BADSESSION); goto out_unlock; } status = htonl(NFS4ERR_BADSLOT); slot = nfs4_lookup_slot(tbl, args->csa_slotid); if (IS_ERR(slot)) goto out_unlock; res->csr_highestslotid = tbl->server_highest_slotid; res->csr_target_highestslotid = tbl->target_highest_slotid; status = validate_seqid(tbl, slot, args); if (status) goto out_unlock; if (!nfs4_try_to_lock_slot(tbl, slot)) { status = htonl(NFS4ERR_DELAY); goto out_unlock; } cps->slot = slot; /* The ca_maxresponsesize_cached is 0 with no DRC */ if (args->csa_cachethis != 0) { status = htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE); goto out_unlock; } /* * Check for pending referring calls. If a match is found, a * related callback was received before the response to the original * call. */ if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists, &tbl->slot_tbl_lock) < 0) { status = htonl(NFS4ERR_DELAY); goto out_unlock; } /* * RFC5661 20.9.3 * If CB_SEQUENCE returns an error, then the state of the slot * (sequence ID, cached reply) MUST NOT change. */ slot->seq_nr = args->csa_sequenceid; out_unlock: spin_unlock(&tbl->slot_tbl_lock); out: cps->clp = clp; /* put in nfs4_callback_compound */ for (i = 0; i < args->csa_nrclists; i++) kfree(args->csa_rclists[i].rcl_refcalls); kfree(args->csa_rclists); if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) { cps->drc_status = status; status = 0; } else res->csr_status = status; trace_nfs4_cb_sequence(args, res, status); return status; } static bool validate_bitmap_values(unsigned long mask) { return (mask & ~RCA4_TYPE_MASK_ALL) == 0; } __be32 nfs4_callback_recallany(void *argp, void *resp, struct cb_process_state *cps) { struct cb_recallanyargs *args = argp; __be32 status; fmode_t flags = 0; status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION); if (!cps->clp) /* set in cb_sequence */ goto out; dprintk_rcu("NFS: RECALL_ANY callback request from %s\n", rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); status = cpu_to_be32(NFS4ERR_INVAL); if (!validate_bitmap_values(args->craa_type_mask)) goto out; status = cpu_to_be32(NFS4_OK); if (test_bit(RCA4_TYPE_MASK_RDATA_DLG, (const unsigned long *) &args->craa_type_mask)) flags = FMODE_READ; if (test_bit(RCA4_TYPE_MASK_WDATA_DLG, (const unsigned long *) &args->craa_type_mask)) flags |= FMODE_WRITE; if (test_bit(RCA4_TYPE_MASK_FILE_LAYOUT, (const unsigned long *) &args->craa_type_mask)) pnfs_recall_all_layouts(cps->clp); if (flags) nfs_expire_unused_delegation_types(cps->clp, flags); out: dprintk("%s: exit with status = %d\n", __func__, ntohl(status)); return status; } /* Reduce the fore channel's max_slots to the target value */ __be32 nfs4_callback_recallslot(void *argp, void *resp, struct cb_process_state *cps) { struct cb_recallslotargs *args = argp; struct nfs4_slot_table *fc_tbl; __be32 status; status = htonl(NFS4ERR_OP_NOT_IN_SESSION); if (!cps->clp) /* set in cb_sequence */ goto out; dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n", rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR), args->crsa_target_highest_slotid); fc_tbl = &cps->clp->cl_session->fc_slot_table; status = htonl(NFS4_OK); nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid); nfs41_notify_server(cps->clp); out: dprintk("%s: exit with status = %d\n", __func__, ntohl(status)); return status; } __be32 nfs4_callback_notify_lock(void *argp, void *resp, struct cb_process_state *cps) { struct cb_notify_lock_args *args = argp; if (!cps->clp) /* set in cb_sequence */ return htonl(NFS4ERR_OP_NOT_IN_SESSION); dprintk_rcu("NFS: CB_NOTIFY_LOCK request from %s\n", rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); /* Don't wake anybody if the string looked bogus */ if (args->cbnl_valid) __wake_up(&cps->clp->cl_lock_waitq, TASK_NORMAL, 0, args); return htonl(NFS4_OK); } #endif /* CONFIG_NFS_V4_1 */