nfs_fha.h revision 261054 
1/*-
2 * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 */
25/* $FreeBSD: stable/10/sys/nfs/nfs_fha.h 261054 2014-01-22 23:52:20Z mav $ */
26
27#ifndef	_NFS_FHA_H
28#define	_NFS_FHA_H 1
29
30#ifdef	_KERNEL
31
32/* Sysctl defaults. */
33#define FHA_DEF_ENABLE			1
34#define FHA_DEF_BIN_SHIFT		22 /* 4MB */
35#define FHA_DEF_MAX_NFSDS_PER_FH	8
36#define FHA_DEF_MAX_REQS_PER_NFSD	0  /* Unlimited */
37
38#define FHA_HASH_SIZE	251
39
40struct fha_ctls {
41	int	 enable;
42	uint32_t bin_shift;
43	uint32_t max_nfsds_per_fh;
44	uint32_t max_reqs_per_nfsd;
45};
46
47/*
48 * These are the entries in the filehandle hash.  They talk about a specific
49 * file, requests against which are being handled by one or more nfsds.  We
50 * keep a chain of nfsds against the file. We only have more than one if reads
51 * are ongoing, and then only if the reads affect disparate regions of the
52 * file.
53 *
54 * In general, we want to assign a new request to an existing nfsd if it is
55 * going to contend with work happening already on that nfsd, or if the
56 * operation is a read and the nfsd is already handling a proximate read.  We
57 * do this to avoid jumping around in the read stream unnecessarily, and to
58 * avoid contention between threads over single files.
59 */
60struct fha_hash_entry {
61	struct mtx *mtx;
62	LIST_ENTRY(fha_hash_entry) link;
63	u_int64_t fh;
64	u_int32_t num_rw;
65	u_int32_t num_exclusive;
66	u_int8_t num_threads;
67	struct svcthread_list threads;
68};
69
70LIST_HEAD(fha_hash_entry_list, fha_hash_entry);
71
72struct fha_hash_slot {
73	struct fha_hash_entry_list list;
74	struct mtx mtx;
75};
76
77/* A structure used for passing around data internally. */
78struct fha_info {
79	u_int64_t fh;
80	off_t offset;
81	int locktype;
82};
83
84struct fha_callbacks {
85	rpcproc_t (*get_procnum)(rpcproc_t procnum);
86	int (*realign)(struct mbuf **mb, int malloc_flags);
87	int (*get_fh)(uint64_t *fh, int v3, struct mbuf **md, caddr_t *dpos);
88	int (*is_read)(rpcproc_t procnum);
89	int (*is_write)(rpcproc_t procnum);
90	int (*get_offset)(struct mbuf **md, caddr_t *dpos, int v3, struct
91			  fha_info *info);
92	int (*no_offset)(rpcproc_t procnum);
93	void (*set_locktype)(rpcproc_t procnum, struct fha_info *info);
94	int (*fhe_stats_sysctl)(SYSCTL_HANDLER_ARGS);
95};
96
97struct fha_params {
98	struct fha_hash_slot fha_hash[FHA_HASH_SIZE];
99	struct sysctl_ctx_list sysctl_ctx;
100	struct sysctl_oid *sysctl_tree;
101	struct fha_ctls ctls;
102	struct fha_callbacks callbacks;
103	char server_name[32];
104	SVCPOOL **pool;
105};
106
107void fha_nd_complete(SVCTHREAD *, struct svc_req *);
108SVCTHREAD *fha_assign(SVCTHREAD *, struct svc_req *, struct fha_params *);
109void fha_init(struct fha_params *softc);
110void fha_uninit(struct fha_params *softc);
111int fhe_stats_sysctl(SYSCTL_HANDLER_ARGS, struct fha_params *softc);
112
113#endif /* _KERNEL */
114#endif /* _NFS_FHA_H_ */
115