From bd9d6a3efa9709e653aafbeb859289feccb8e70c Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Mon, 11 Sep 2023 14:49:46 +0200 Subject: NFSD: add rpc_status netlink support Introduce rpc_status netlink support for NFSD in order to dump pending RPC requests debugging information from userspace. Closes: https://bugzilla.linux-nfs.org/show_bug.cgi?id=366 Tested-by: Jeff Layton Signed-off-by: Lorenzo Bianconi Signed-off-by: Chuck Lever --- fs/nfsd/nfsctl.c | 188 ++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 187 insertions(+), 1 deletion(-) (limited to 'fs/nfsd/nfsctl.c') diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index 364ccd0be1c1..739ed5bf71cd 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -1496,19 +1496,200 @@ static int create_proc_exports_entry(void) unsigned int nfsd_net_id; +/** + * nfsd_nl_rpc_status_get_start - Prepare rpc_status_get dumpit + * @cb: netlink metadata and command arguments + * + * Return values: + * %0: The rpc_status_get command may proceed + * %-ENODEV: There is no NFSD running in this namespace + */ int nfsd_nl_rpc_status_get_start(struct netlink_callback *cb) { + struct nfsd_net *nn = net_generic(sock_net(cb->skb->sk), nfsd_net_id); + int ret = -ENODEV; + + mutex_lock(&nfsd_mutex); + if (nn->nfsd_serv) { + svc_get(nn->nfsd_serv); + ret = 0; + } + mutex_unlock(&nfsd_mutex); + + return ret; +} + +static int nfsd_genl_rpc_status_compose_msg(struct sk_buff *skb, + struct netlink_callback *cb, + struct nfsd_genl_rqstp *rqstp) +{ + void *hdr; + u32 i; + + hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, + &nfsd_nl_family, 0, NFSD_CMD_RPC_STATUS_GET); + if (!hdr) + return -ENOBUFS; + + if (nla_put_be32(skb, NFSD_A_RPC_STATUS_XID, rqstp->rq_xid) || + nla_put_u32(skb, NFSD_A_RPC_STATUS_FLAGS, rqstp->rq_flags) || + nla_put_u32(skb, NFSD_A_RPC_STATUS_PROG, rqstp->rq_prog) || + nla_put_u32(skb, NFSD_A_RPC_STATUS_PROC, rqstp->rq_proc) || + nla_put_u8(skb, NFSD_A_RPC_STATUS_VERSION, rqstp->rq_vers) || + nla_put_s64(skb, NFSD_A_RPC_STATUS_SERVICE_TIME, + ktime_to_us(rqstp->rq_stime), + NFSD_A_RPC_STATUS_PAD)) + return -ENOBUFS; + + switch (rqstp->rq_saddr.sa_family) { + case AF_INET: { + const struct sockaddr_in *s_in, *d_in; + + s_in = (const struct sockaddr_in *)&rqstp->rq_saddr; + d_in = (const struct sockaddr_in *)&rqstp->rq_daddr; + if (nla_put_in_addr(skb, NFSD_A_RPC_STATUS_SADDR4, + s_in->sin_addr.s_addr) || + nla_put_in_addr(skb, NFSD_A_RPC_STATUS_DADDR4, + d_in->sin_addr.s_addr) || + nla_put_be16(skb, NFSD_A_RPC_STATUS_SPORT, + s_in->sin_port) || + nla_put_be16(skb, NFSD_A_RPC_STATUS_DPORT, + d_in->sin_port)) + return -ENOBUFS; + break; + } + case AF_INET6: { + const struct sockaddr_in6 *s_in, *d_in; + + s_in = (const struct sockaddr_in6 *)&rqstp->rq_saddr; + d_in = (const struct sockaddr_in6 *)&rqstp->rq_daddr; + if (nla_put_in6_addr(skb, NFSD_A_RPC_STATUS_SADDR6, + &s_in->sin6_addr) || + nla_put_in6_addr(skb, NFSD_A_RPC_STATUS_DADDR6, + &d_in->sin6_addr) || + nla_put_be16(skb, NFSD_A_RPC_STATUS_SPORT, + s_in->sin6_port) || + nla_put_be16(skb, NFSD_A_RPC_STATUS_DPORT, + d_in->sin6_port)) + return -ENOBUFS; + break; + } + } + + for (i = 0; i < rqstp->rq_opcnt; i++) + if (nla_put_u32(skb, NFSD_A_RPC_STATUS_COMPOUND_OPS, + rqstp->rq_opnum[i])) + return -ENOBUFS; + + genlmsg_end(skb, hdr); return 0; } +/** + * nfsd_nl_rpc_status_get_dumpit - Handle rpc_status_get dumpit + * @skb: reply buffer + * @cb: netlink metadata and command arguments + * + * Returns the size of the reply or a negative errno. + */ int nfsd_nl_rpc_status_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb) { - return 0; + struct nfsd_net *nn = net_generic(sock_net(skb->sk), nfsd_net_id); + int i, ret, rqstp_index = 0; + + rcu_read_lock(); + + for (i = 0; i < nn->nfsd_serv->sv_nrpools; i++) { + struct svc_rqst *rqstp; + + if (i < cb->args[0]) /* already consumed */ + continue; + + rqstp_index = 0; + list_for_each_entry_rcu(rqstp, + &nn->nfsd_serv->sv_pools[i].sp_all_threads, + rq_all) { + struct nfsd_genl_rqstp genl_rqstp; + unsigned int status_counter; + + if (rqstp_index++ < cb->args[1]) /* already consumed */ + continue; + /* + * Acquire rq_status_counter before parsing the rqst + * fields. rq_status_counter is set to an odd value in + * order to notify the consumers the rqstp fields are + * meaningful. + */ + status_counter = + smp_load_acquire(&rqstp->rq_status_counter); + if (!(status_counter & 1)) + continue; + + genl_rqstp.rq_xid = rqstp->rq_xid; + genl_rqstp.rq_flags = rqstp->rq_flags; + genl_rqstp.rq_vers = rqstp->rq_vers; + genl_rqstp.rq_prog = rqstp->rq_prog; + genl_rqstp.rq_proc = rqstp->rq_proc; + genl_rqstp.rq_stime = rqstp->rq_stime; + genl_rqstp.rq_opcnt = 0; + memcpy(&genl_rqstp.rq_daddr, svc_daddr(rqstp), + sizeof(struct sockaddr)); + memcpy(&genl_rqstp.rq_saddr, svc_addr(rqstp), + sizeof(struct sockaddr)); + +#ifdef CONFIG_NFSD_V4 + if (rqstp->rq_vers == NFS4_VERSION && + rqstp->rq_proc == NFSPROC4_COMPOUND) { + /* NFSv4 compound */ + struct nfsd4_compoundargs *args; + int j; + + args = rqstp->rq_argp; + genl_rqstp.rq_opcnt = args->opcnt; + for (j = 0; j < genl_rqstp.rq_opcnt; j++) + genl_rqstp.rq_opnum[j] = + args->ops[j].opnum; + } +#endif /* CONFIG_NFSD_V4 */ + + /* + * Acquire rq_status_counter before reporting the rqst + * fields to the user. + */ + if (smp_load_acquire(&rqstp->rq_status_counter) != + status_counter) + continue; + + ret = nfsd_genl_rpc_status_compose_msg(skb, cb, + &genl_rqstp); + if (ret) + goto out; + } + } + + cb->args[0] = i; + cb->args[1] = rqstp_index; + ret = skb->len; +out: + rcu_read_unlock(); + + return ret; } +/** + * nfsd_nl_rpc_status_get_done - rpc_status_get dumpit post-processing + * @cb: netlink metadata and command arguments + * + * Return values: + * %0: Success + */ int nfsd_nl_rpc_status_get_done(struct netlink_callback *cb) { + mutex_lock(&nfsd_mutex); + nfsd_put(sock_net(cb->skb->sk)); + mutex_unlock(&nfsd_mutex); + return 0; } @@ -1606,6 +1787,10 @@ static int __init init_nfsd(void) retval = register_filesystem(&nfsd_fs_type); if (retval) goto out_free_all; + retval = genl_register_family(&nfsd_nl_family); + if (retval) + goto out_free_all; + return 0; out_free_all: nfsd4_destroy_laundry_wq(); @@ -1630,6 +1815,7 @@ out_free_slabs: static void __exit exit_nfsd(void) { + genl_unregister_family(&nfsd_nl_family); unregister_filesystem(&nfsd_fs_type); nfsd4_destroy_laundry_wq(); unregister_cld_notifier(); -- cgit