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