^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Generic dynamic event control interface
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2018 Masami Hiramatsu <mhiramat@kernel.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/debugfs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/list.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/mm.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/mutex.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/tracefs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include "trace.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include "trace_dynevent.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) static DEFINE_MUTEX(dyn_event_ops_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) static LIST_HEAD(dyn_event_ops_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) int dyn_event_register(struct dyn_event_operations *ops)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) if (!ops || !ops->create || !ops->show || !ops->is_busy ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) !ops->free || !ops->match)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) INIT_LIST_HEAD(&ops->list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) mutex_lock(&dyn_event_ops_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) list_add_tail(&ops->list, &dyn_event_ops_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) mutex_unlock(&dyn_event_ops_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) int dyn_event_release(int argc, char **argv, struct dyn_event_operations *type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) struct dyn_event *pos, *n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) char *system = NULL, *event, *p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) int ret = -ENOENT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) if (argv[0][0] == '-') {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) if (argv[0][1] != ':')
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) event = &argv[0][2];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) event = strchr(argv[0], ':');
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) if (!event)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) event++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) argc--; argv++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) p = strchr(event, '/');
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) if (p) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) system = event;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) event = p + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) *p = '\0';
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) if (event[0] == '\0')
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) mutex_lock(&event_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) for_each_dyn_event_safe(pos, n) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) if (type && type != pos->ops)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) if (!pos->ops->match(system, event,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) argc, (const char **)argv, pos))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) ret = pos->ops->free(pos);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) mutex_unlock(&event_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) static int create_dyn_event(int argc, char **argv)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) struct dyn_event_operations *ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) int ret = -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) if (argv[0][0] == '-' || argv[0][0] == '!')
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) return dyn_event_release(argc, argv, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) mutex_lock(&dyn_event_ops_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) list_for_each_entry(ops, &dyn_event_ops_list, list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) ret = ops->create(argc, (const char **)argv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) if (!ret || ret != -ECANCELED)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) mutex_unlock(&dyn_event_ops_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) if (ret == -ECANCELED)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) ret = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) /* Protected by event_mutex */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) LIST_HEAD(dyn_event_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) void *dyn_event_seq_start(struct seq_file *m, loff_t *pos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) mutex_lock(&event_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) return seq_list_start(&dyn_event_list, *pos);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) void *dyn_event_seq_next(struct seq_file *m, void *v, loff_t *pos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) return seq_list_next(v, &dyn_event_list, pos);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) void dyn_event_seq_stop(struct seq_file *m, void *v)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) mutex_unlock(&event_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) static int dyn_event_seq_show(struct seq_file *m, void *v)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) struct dyn_event *ev = v;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) if (ev && ev->ops)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) return ev->ops->show(m, ev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) static const struct seq_operations dyn_event_seq_op = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) .start = dyn_event_seq_start,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) .next = dyn_event_seq_next,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) .stop = dyn_event_seq_stop,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) .show = dyn_event_seq_show
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) * dyn_events_release_all - Release all specific events
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) * @type: the dyn_event_operations * which filters releasing events
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) * This releases all events which ->ops matches @type. If @type is NULL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) * all events are released.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) * Return -EBUSY if any of them are in use, and return other errors when
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) * it failed to free the given event. Except for -EBUSY, event releasing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) * process will be aborted at that point and there may be some other
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) * releasable events on the list.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) int dyn_events_release_all(struct dyn_event_operations *type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) struct dyn_event *ev, *tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) int ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) mutex_lock(&event_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) for_each_dyn_event(ev) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) if (type && ev->ops != type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) if (ev->ops->is_busy(ev)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) ret = -EBUSY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) for_each_dyn_event_safe(ev, tmp) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) if (type && ev->ops != type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) ret = ev->ops->free(ev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) mutex_unlock(&event_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) static int dyn_event_open(struct inode *inode, struct file *file)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) ret = tracing_check_open_get_tr(NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) ret = dyn_events_release_all(NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) if (ret < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) return seq_open(file, &dyn_event_seq_op);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) static ssize_t dyn_event_write(struct file *file, const char __user *buffer,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) size_t count, loff_t *ppos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) return trace_parse_run_command(file, buffer, count, ppos,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) create_dyn_event);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) static const struct file_operations dynamic_events_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) .owner = THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) .open = dyn_event_open,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) .read = seq_read,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) .llseek = seq_lseek,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) .release = seq_release,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) .write = dyn_event_write,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) /* Make a tracefs interface for controlling dynamic events */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) static __init int init_dynamic_event(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) struct dentry *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) ret = tracing_init_dentry();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) entry = tracefs_create_file("dynamic_events", 0644, NULL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) NULL, &dynamic_events_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) /* Event list interface */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) if (!entry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) pr_warn("Could not create tracefs 'dynamic_events' entry\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) fs_initcall(init_dynamic_event);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) * dynevent_arg_add - Add an arg to a dynevent_cmd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) * @cmd: A pointer to the dynevent_cmd struct representing the new event cmd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) * @arg: The argument to append to the current cmd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) * @check_arg: An (optional) pointer to a function checking arg sanity
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) * Append an argument to a dynevent_cmd. The argument string will be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) * appended to the current cmd string, followed by a separator, if
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) * applicable. Before the argument is added, the @check_arg function,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) * if present, will be used to check the sanity of the current arg
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) * string.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) * The cmd string and separator should be set using the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) * dynevent_arg_init() before any arguments are added using this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) * function.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) * Return: 0 if successful, error otherwise.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) int dynevent_arg_add(struct dynevent_cmd *cmd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) struct dynevent_arg *arg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) dynevent_check_arg_fn_t check_arg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) int ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) if (check_arg) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) ret = check_arg(arg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) ret = seq_buf_printf(&cmd->seq, " %s%c", arg->str, arg->separator);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) pr_err("String is too long: %s%c\n", arg->str, arg->separator);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) return -E2BIG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) * dynevent_arg_pair_add - Add an arg pair to a dynevent_cmd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) * @cmd: A pointer to the dynevent_cmd struct representing the new event cmd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) * @arg_pair: The argument pair to append to the current cmd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) * @check_arg: An (optional) pointer to a function checking arg sanity
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) * Append an argument pair to a dynevent_cmd. An argument pair
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) * consists of a left-hand-side argument and a right-hand-side
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) * argument separated by an operator, which can be whitespace, all
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) * followed by a separator, if applicable. This can be used to add
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) * arguments of the form 'type variable_name;' or 'x+y'.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) * The lhs argument string will be appended to the current cmd string,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) * followed by an operator, if applicable, followd by the rhs string,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) * followed finally by a separator, if applicable. Before the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) * argument is added, the @check_arg function, if present, will be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) * used to check the sanity of the current arg strings.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) * The cmd strings, operator, and separator should be set using the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) * dynevent_arg_pair_init() before any arguments are added using this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) * function.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) * Return: 0 if successful, error otherwise.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) int dynevent_arg_pair_add(struct dynevent_cmd *cmd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) struct dynevent_arg_pair *arg_pair,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) dynevent_check_arg_fn_t check_arg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) int ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) if (check_arg) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) ret = check_arg(arg_pair);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) ret = seq_buf_printf(&cmd->seq, " %s%c%s%c", arg_pair->lhs,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) arg_pair->operator, arg_pair->rhs,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) arg_pair->separator);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) pr_err("field string is too long: %s%c%s%c\n", arg_pair->lhs,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) arg_pair->operator, arg_pair->rhs,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) arg_pair->separator);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) return -E2BIG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) * dynevent_str_add - Add a string to a dynevent_cmd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) * @cmd: A pointer to the dynevent_cmd struct representing the new event cmd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) * @str: The string to append to the current cmd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) * Append a string to a dynevent_cmd. The string will be appended to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) * the current cmd string as-is, with nothing prepended or appended.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) * Return: 0 if successful, error otherwise.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) int dynevent_str_add(struct dynevent_cmd *cmd, const char *str)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) int ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) ret = seq_buf_puts(&cmd->seq, str);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) pr_err("String is too long: %s\n", str);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) return -E2BIG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) * dynevent_cmd_init - Initialize a dynevent_cmd object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) * @cmd: A pointer to the dynevent_cmd struct representing the cmd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) * @buf: A pointer to the buffer to generate the command into
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) * @maxlen: The length of the buffer the command will be generated into
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) * @type: The type of the cmd, checked against further operations
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) * @run_command: The type-specific function that will actually run the command
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) * Initialize a dynevent_cmd. A dynevent_cmd is used to build up and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) * run dynamic event creation commands, such as commands for creating
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) * synthetic and kprobe events. Before calling any of the functions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) * used to build the command, a dynevent_cmd object should be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) * instantiated and initialized using this function.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) * The initialization sets things up by saving a pointer to the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) * user-supplied buffer and its length via the @buf and @maxlen
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) * params, and by saving the cmd-specific @type and @run_command
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) * params which are used to check subsequent dynevent_cmd operations
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) * and actually run the command when complete.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) void dynevent_cmd_init(struct dynevent_cmd *cmd, char *buf, int maxlen,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) enum dynevent_type type,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) dynevent_create_fn_t run_command)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) memset(cmd, '\0', sizeof(*cmd));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) seq_buf_init(&cmd->seq, buf, maxlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) cmd->type = type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) cmd->run_command = run_command;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) * dynevent_arg_init - Initialize a dynevent_arg object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) * @arg: A pointer to the dynevent_arg struct representing the arg
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) * @separator: An (optional) separator, appended after adding the arg
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) * Initialize a dynevent_arg object. A dynevent_arg represents an
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) * object used to append single arguments to the current command
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) * string. After the arg string is successfully appended to the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) * command string, the optional @separator is appended. If no
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) * separator was specified when initializing the arg, a space will be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) * appended.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) void dynevent_arg_init(struct dynevent_arg *arg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) char separator)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) memset(arg, '\0', sizeof(*arg));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) if (!separator)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) separator = ' ';
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) arg->separator = separator;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) * dynevent_arg_pair_init - Initialize a dynevent_arg_pair object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) * @arg_pair: A pointer to the dynevent_arg_pair struct representing the arg
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) * @operator: An (optional) operator, appended after adding the first arg
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) * @separator: An (optional) separator, appended after adding the second arg
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) * Initialize a dynevent_arg_pair object. A dynevent_arg_pair
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) * represents an object used to append argument pairs such as 'type
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) * variable_name;' or 'x+y' to the current command string. An
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) * argument pair consists of a left-hand-side argument and a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) * right-hand-side argument separated by an operator, which can be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) * whitespace, all followed by a separator, if applicable. After the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) * first arg string is successfully appended to the command string,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) * the optional @operator is appended, followed by the second arg and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) * optional @separator. If no separator was specified when
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) * initializing the arg, a space will be appended.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) void dynevent_arg_pair_init(struct dynevent_arg_pair *arg_pair,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) char operator, char separator)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) memset(arg_pair, '\0', sizeof(*arg_pair));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) if (!operator)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) operator = ' ';
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) arg_pair->operator = operator;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) if (!separator)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) separator = ' ';
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) arg_pair->separator = separator;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) * dynevent_create - Create the dynamic event contained in dynevent_cmd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) * @cmd: The dynevent_cmd object containing the dynamic event creation command
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) * Once a dynevent_cmd object has been successfully built up via the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) * dynevent_cmd_init(), dynevent_arg_add() and dynevent_arg_pair_add()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) * functions, this function runs the final command to actually create
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) * the event.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) * Return: 0 if the event was successfully created, error otherwise.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) int dynevent_create(struct dynevent_cmd *cmd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) return cmd->run_command(cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) EXPORT_SYMBOL_GPL(dynevent_create);
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
3 Commits
0 Branches
0 Tags