xref: /freebsd/sys/fs/nfsserver/nfs_fha_new.h (revision d0b2dbfa)
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 
47 struct 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  */
69 struct 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 
79 LIST_HEAD(fha_hash_entry_list, fha_hash_entry);
80 
81 struct 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. */
87 struct fha_info {
88 	u_int64_t fh;
89 	off_t offset;
90 	int locktype;
91 	int read;
92 	int write;
93 };
94 
95 struct fha_params {
96 	struct fha_hash_slot fha_hash[FHA_HASH_SIZE];
97 	char server_name[32];
98 };
99 
100 SVCTHREAD *fhanew_assign(SVCTHREAD *this_thread, struct svc_req *req);
101 void fhanew_nd_complete(SVCTHREAD *, struct svc_req *);
102 #endif /* _KERNEL */
103 
104 #endif /* _NFS_FHA_NEW_H */
105