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/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 #include <sys/list.h> 32 #include <sys/mutex.h> 33 #include <sys/procfs_list.h> 34 35 typedef struct procfs_list_iter { 36 procfs_list_t *pli_pl; 37 void *pli_elt; 38 } pli_t; 39 40 void 41 seq_printf(struct seq_file *f, const char *fmt, ...) 42 { 43 va_list adx; 44 45 va_start(adx, fmt); 46 (void) vsnprintf(f->sf_buf, f->sf_size, fmt, adx); 47 va_end(adx); 48 } 49 50 static int 51 procfs_list_update(kstat_t *ksp, int rw) 52 { 53 procfs_list_t *pl = ksp->ks_private; 54 55 if (rw == KSTAT_WRITE) 56 pl->pl_clear(pl); 57 58 return (0); 59 } 60 61 static int 62 procfs_list_data(char *buf, size_t size, void *data) 63 { 64 pli_t *p; 65 void *elt; 66 procfs_list_t *pl; 67 struct seq_file f; 68 69 p = data; 70 pl = p->pli_pl; 71 elt = p->pli_elt; 72 free(p, M_TEMP); 73 f.sf_buf = buf; 74 f.sf_size = size; 75 return (pl->pl_show(&f, elt)); 76 } 77 78 static void * 79 procfs_list_addr(kstat_t *ksp, loff_t n) 80 { 81 procfs_list_t *pl = ksp->ks_private; 82 void *elt = ksp->ks_private1; 83 pli_t *p = NULL; 84 85 86 if (n == 0) 87 ksp->ks_private1 = list_head(&pl->pl_list); 88 else if (elt) 89 ksp->ks_private1 = list_next(&pl->pl_list, elt); 90 91 if (ksp->ks_private1) { 92 p = malloc(sizeof (*p), M_TEMP, M_WAITOK); 93 p->pli_pl = pl; 94 p->pli_elt = ksp->ks_private1; 95 } 96 97 return (p); 98 } 99 100 void 101 procfs_list_install(const char *module, 102 const char *submodule, 103 const char *name, 104 mode_t mode, 105 procfs_list_t *procfs_list, 106 int (*show)(struct seq_file *f, void *p), 107 int (*show_header)(struct seq_file *f), 108 int (*clear)(procfs_list_t *procfs_list), 109 size_t procfs_list_node_off) 110 { 111 kstat_t *procfs_kstat; 112 113 mutex_init(&procfs_list->pl_lock, NULL, MUTEX_DEFAULT, NULL); 114 list_create(&procfs_list->pl_list, 115 procfs_list_node_off + sizeof (procfs_list_node_t), 116 procfs_list_node_off + offsetof(procfs_list_node_t, pln_link)); 117 procfs_list->pl_show = show; 118 procfs_list->pl_show_header = show_header; 119 procfs_list->pl_clear = clear; 120 procfs_list->pl_next_id = 1; 121 procfs_list->pl_node_offset = procfs_list_node_off; 122 123 procfs_kstat = kstat_create(module, 0, name, submodule, 124 KSTAT_TYPE_RAW, 0, KSTAT_FLAG_VIRTUAL); 125 126 if (procfs_kstat) { 127 procfs_kstat->ks_lock = &procfs_list->pl_lock; 128 procfs_kstat->ks_ndata = UINT32_MAX; 129 procfs_kstat->ks_private = procfs_list; 130 procfs_kstat->ks_update = procfs_list_update; 131 kstat_set_seq_raw_ops(procfs_kstat, show_header, 132 procfs_list_data, procfs_list_addr); 133 kstat_install(procfs_kstat); 134 procfs_list->pl_private = procfs_kstat; 135 } 136 } 137 138 void 139 procfs_list_uninstall(procfs_list_t *procfs_list) 140 {} 141 142 void 143 procfs_list_destroy(procfs_list_t *procfs_list) 144 { 145 ASSERT(list_is_empty(&procfs_list->pl_list)); 146 kstat_delete(procfs_list->pl_private); 147 list_destroy(&procfs_list->pl_list); 148 mutex_destroy(&procfs_list->pl_lock); 149 } 150 151 #define NODE_ID(procfs_list, obj) \ 152 (((procfs_list_node_t *)(((char *)obj) + \ 153 (procfs_list)->pl_node_offset))->pln_id) 154 155 void 156 procfs_list_add(procfs_list_t *procfs_list, void *p) 157 { 158 ASSERT(MUTEX_HELD(&procfs_list->pl_lock)); 159 NODE_ID(procfs_list, p) = procfs_list->pl_next_id++; 160 list_insert_tail(&procfs_list->pl_list, p); 161 } 162