1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3 * Copyright (c) 2020 iXsystems, Inc.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 */
28
29 #include <sys/list.h>
30 #include <sys/mutex.h>
31 #include <sys/procfs_list.h>
32
33 typedef struct procfs_list_iter {
34 procfs_list_t *pli_pl;
35 void *pli_elt;
36 } pli_t;
37
38 void
seq_printf(struct seq_file * f,const char * fmt,...)39 seq_printf(struct seq_file *f, const char *fmt, ...)
40 {
41 va_list adx;
42
43 va_start(adx, fmt);
44 (void) vsnprintf(f->sf_buf, f->sf_size, fmt, adx);
45 va_end(adx);
46 }
47
48 static int
procfs_list_update(kstat_t * ksp,int rw)49 procfs_list_update(kstat_t *ksp, int rw)
50 {
51 procfs_list_t *pl = ksp->ks_private;
52
53 if (rw == KSTAT_WRITE)
54 pl->pl_clear(pl);
55
56 return (0);
57 }
58
59 static int
procfs_list_data(char * buf,size_t size,void * data)60 procfs_list_data(char *buf, size_t size, void *data)
61 {
62 pli_t *p;
63 void *elt;
64 procfs_list_t *pl;
65 struct seq_file f;
66
67 p = data;
68 pl = p->pli_pl;
69 elt = p->pli_elt;
70 free(p, M_TEMP);
71 f.sf_buf = buf;
72 f.sf_size = size;
73 return (pl->pl_show(&f, elt));
74 }
75
76 static void *
procfs_list_addr(kstat_t * ksp,loff_t n)77 procfs_list_addr(kstat_t *ksp, loff_t n)
78 {
79 procfs_list_t *pl = ksp->ks_private;
80 void *elt = ksp->ks_private1;
81 pli_t *p = NULL;
82
83
84 if (n == 0)
85 ksp->ks_private1 = list_head(&pl->pl_list);
86 else if (elt)
87 ksp->ks_private1 = list_next(&pl->pl_list, elt);
88
89 if (ksp->ks_private1) {
90 p = malloc(sizeof (*p), M_TEMP, M_WAITOK);
91 p->pli_pl = pl;
92 p->pli_elt = ksp->ks_private1;
93 }
94
95 return (p);
96 }
97
98 void
procfs_list_install(const char * module,const char * submodule,const char * name,mode_t mode,procfs_list_t * procfs_list,int (* show)(struct seq_file * f,void * p),int (* show_header)(struct seq_file * f),int (* clear)(procfs_list_t * procfs_list),size_t procfs_list_node_off)99 procfs_list_install(const char *module,
100 const char *submodule,
101 const char *name,
102 mode_t mode,
103 procfs_list_t *procfs_list,
104 int (*show)(struct seq_file *f, void *p),
105 int (*show_header)(struct seq_file *f),
106 int (*clear)(procfs_list_t *procfs_list),
107 size_t procfs_list_node_off)
108 {
109 kstat_t *procfs_kstat;
110
111 mutex_init(&procfs_list->pl_lock, NULL, MUTEX_DEFAULT, NULL);
112 list_create(&procfs_list->pl_list,
113 procfs_list_node_off + sizeof (procfs_list_node_t),
114 procfs_list_node_off + offsetof(procfs_list_node_t, pln_link));
115 procfs_list->pl_show = show;
116 procfs_list->pl_show_header = show_header;
117 procfs_list->pl_clear = clear;
118 procfs_list->pl_next_id = 1;
119 procfs_list->pl_node_offset = procfs_list_node_off;
120
121 procfs_kstat = kstat_create(module, 0, name, submodule,
122 KSTAT_TYPE_RAW, 0, KSTAT_FLAG_VIRTUAL);
123
124 if (procfs_kstat) {
125 procfs_kstat->ks_lock = &procfs_list->pl_lock;
126 procfs_kstat->ks_ndata = UINT32_MAX;
127 procfs_kstat->ks_private = procfs_list;
128 procfs_kstat->ks_update = procfs_list_update;
129 kstat_set_seq_raw_ops(procfs_kstat, show_header,
130 procfs_list_data, procfs_list_addr);
131 kstat_install(procfs_kstat);
132 procfs_list->pl_private = procfs_kstat;
133 }
134 }
135
136 void
procfs_list_uninstall(procfs_list_t * procfs_list)137 procfs_list_uninstall(procfs_list_t *procfs_list)
138 {}
139
140 void
procfs_list_destroy(procfs_list_t * procfs_list)141 procfs_list_destroy(procfs_list_t *procfs_list)
142 {
143 ASSERT(list_is_empty(&procfs_list->pl_list));
144 kstat_delete(procfs_list->pl_private);
145 list_destroy(&procfs_list->pl_list);
146 mutex_destroy(&procfs_list->pl_lock);
147 }
148
149 #define NODE_ID(procfs_list, obj) \
150 (((procfs_list_node_t *)(((char *)obj) + \
151 (procfs_list)->pl_node_offset))->pln_id)
152
153 void
procfs_list_add(procfs_list_t * procfs_list,void * p)154 procfs_list_add(procfs_list_t *procfs_list, void *p)
155 {
156 ASSERT(MUTEX_HELD(&procfs_list->pl_lock));
157 NODE_ID(procfs_list, p) = procfs_list->pl_next_id++;
158 list_insert_tail(&procfs_list->pl_list, p);
159 }
160