1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
5 * Copyright (c) 2013 Spectra Logic Corporation
6 *
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#ifndef	_NFS_FHA_NEW_H
31#define	_NFS_FHA_NEW_H 1
32
33#ifdef	_KERNEL
34
35#define	FHANEW_SERVER_NAME	"nfsd"
36
37/* Sysctl defaults. */
38#define FHA_DEF_ENABLE			1
39#define FHA_DEF_READ			1
40#define FHA_DEF_WRITE			1
41#define FHA_DEF_BIN_SHIFT		22 /* 4MB */
42#define FHA_DEF_MAX_NFSDS_PER_FH	8
43#define FHA_DEF_MAX_REQS_PER_NFSD	0  /* Unlimited */
44
45#define FHA_HASH_SIZE	251
46
47struct fha_ctls {
48	int	 enable;
49	int	 read;
50	int	 write;
51	uint32_t bin_shift;
52	uint32_t max_nfsds_per_fh;
53	uint32_t max_reqs_per_nfsd;
54};
55
56/*
57 * These are the entries in the filehandle hash.  They talk about a specific
58 * file, requests against which are being handled by one or more nfsds.  We
59 * keep a chain of nfsds against the file. We only have more than one if reads
60 * are ongoing, and then only if the reads affect disparate regions of the
61 * file.
62 *
63 * In general, we want to assign a new request to an existing nfsd if it is
64 * going to contend with work happening already on that nfsd, or if the
65 * operation is a read and the nfsd is already handling a proximate read.  We
66 * do this to avoid jumping around in the read stream unnecessarily, and to
67 * avoid contention between threads over single files.
68 */
69struct fha_hash_entry {
70	struct mtx *mtx;
71	LIST_ENTRY(fha_hash_entry) link;
72	u_int64_t fh;
73	u_int32_t num_rw;
74	u_int32_t num_exclusive;
75	u_int8_t num_threads;
76	struct svcthread_list threads;
77};
78
79LIST_HEAD(fha_hash_entry_list, fha_hash_entry);
80
81struct fha_hash_slot {
82	struct fha_hash_entry_list list;
83	struct mtx mtx;
84};
85
86/* A structure used for passing around data internally. */
87struct fha_info {
88	u_int64_t fh;
89	off_t offset;
90	int locktype;
91	int read;
92	int write;
93};
94
95struct fha_params {
96	struct fha_hash_slot fha_hash[FHA_HASH_SIZE];
97	char server_name[32];
98};
99
100SVCTHREAD *fhanew_assign(SVCTHREAD *this_thread, struct svc_req *req);
101void fhanew_nd_complete(SVCTHREAD *, struct svc_req *);
102#endif /* _KERNEL */
103
104#endif /* _NFS_FHA_NEW_H */
105