ref: a655555ac0f3da432e6503bccdaad812c94438c7
parent: 4bf9cb19de3716b50eb5e570fc5683eafbe83b71
author: Timo Teräs <timo.teras@iki.fi>
date: Fri Nov 18 14:54:43 CST 2016
nlplug-findfs: handle uevent strictly after mdev execution
--- a/nlplug-findfs.c
+++ b/nlplug-findfs.c
@@ -89,6 +89,7 @@
struct list_head {struct list_head *next, *prev;
};
+#define LIST_INITIALIZER(l) (struct list_head){ .next = &l, .prev = &l }static inline void list_init(struct list_head *list)
{@@ -171,7 +172,9 @@
struct spawn_task {struct list_head node;
+ void (*done)(void *ctx, int status);
pid_t pid;
+ void *ctx;
char **argv, **envp;
};
@@ -193,6 +196,8 @@
list_init(&mgr->queue);
for (i = 0; i < SPAWNMGR_PID_HASH_SIZE; i++)
list_init(&mgr->running[i]);
+
+ dbg("max_running=%d", mgr->max_running);}
static void spawn_execute(struct spawn_manager *mgr, struct spawn_task *task)
@@ -199,7 +204,6 @@
{pid_t pid;
- dbg("[%d/%d] running %s", mgr->num_running+1, mgr->max_running, task->argv[0]); if (!(pid = fork())) {if (execve(task->argv[0], task->argv, task->envp ? task->envp : default_envp) < 0)
err(1, task->argv[0]);
@@ -211,9 +215,11 @@
task->pid = pid;
list_add_tail(&task->node, &mgr->running[pid % SPAWNMGR_PID_HASH_SIZE]);
mgr->num_running++;
+
+ dbg("[%d,%d] spawned %s", pid, mgr->num_running, task->argv[0]);}
-static void spawn_command(struct spawn_manager *mgr, char **argv, char **envp)
+static void spawn_command_cb(struct spawn_manager *mgr, char **argv, char **envp, void (*done)(void *, int), void *ctx)
{struct spawn_task *task;
@@ -220,10 +226,12 @@
task = malloc(sizeof *task);
if (!task) return;
*task = (struct spawn_task) {+ .done = done,
+ .node = LIST_INITIALIZER(task->node),
.argv = clone_array(argv),
.envp = clone_array(envp),
+ .ctx = ctx,
};
- list_init(&task->node);
if (mgr->num_running < mgr->max_running)
spawn_execute(mgr, task);
@@ -231,8 +239,13 @@
list_add_tail(&task->node, &mgr->queue);
}
-static void spawn_reap(struct spawn_manager *mgr, pid_t pid)
+static void spawn_command(struct spawn_manager *mgr, char **argv, char **envp)
{+ spawn_command_cb(mgr, argv, envp, 0, 0);
+}
+
+static void spawn_reap(struct spawn_manager *mgr, pid_t pid, int status)
+{struct spawn_task *task;
list_for_each_entry(task, &mgr->running[pid % SPAWNMGR_PID_HASH_SIZE], node) {@@ -243,6 +256,8 @@
return;
found:
+ if (task->done) task->done(task->ctx, status);
+
mgr->num_running--;
list_del(&task->node);
free(task->argv);
@@ -249,6 +264,8 @@
free(task->envp);
free(task);
+ dbg("[%d,%d] reaped", pid, mgr->num_running);+
if (!list_empty(&mgr->queue) && mgr->num_running < mgr->max_running) {struct spawn_task *task = list_next(&mgr->queue, struct spawn_task, node);
list_del(&task->node);
@@ -261,20 +278,6 @@
return mgr->num_running || !list_empty(&mgr->queue);
}
-struct uevent {- char *buf;
- size_t bufsize;
- char *message;
- char *subsystem;
- char *action;
- char *modalias;
- char *devname;
- char *major;
- char *minor;
- char devnode[256];
- char *envp[64];
-};
-
struct cryptconf {char *device;
char *name;
@@ -284,6 +287,7 @@
struct ueventconf {char **program_argv;
char *search_device;
+ blkid_cache blkid_cache;
struct cryptconf crypt;
char *subsystem_filter;
int modalias_count;
@@ -300,7 +304,35 @@
pthread_mutex_t cryptsetup_mutex;
};
+struct uevent {+ struct ueventconf *conf;
+ int ref;
+ size_t bufsize;
+ char *message;
+ char *subsystem;
+ char *action;
+ char *modalias;
+ char *devname;
+ char *major;
+ char *minor;
+ char devnode[256];
+ char *envp[64];
+ char buf[];
+};
+static struct uevent *uevent_ref(struct uevent *ev)
+{+ ev->ref++;
+ return ev;
+}
+
+static void uevent_unref(struct uevent *ev)
+{+ ev->ref--;
+ if (ev->ref != 0) return;
+ free(ev);
+}
+
static void sighandler(int sig)
{ switch (sig) {@@ -731,7 +763,7 @@
static int searchdev(struct uevent *ev, const char *searchdev, char *bootrepos,
const char *apkovls)
{- static blkid_cache cache = NULL;
+ struct ueventconf *conf = ev->conf;
char *type = NULL, *label = NULL, *uuid = NULL;
int rc = 0;
@@ -744,18 +776,18 @@
return FOUND_DEVICE;
}
- if (cache == NULL)
- blkid_get_cache(&cache, NULL);
+ if (conf->blkid_cache == NULL)
+ blkid_get_cache(&conf->blkid_cache, NULL);
- type = blkid_get_tag_value(cache, "TYPE", ev->devnode);
+ type = blkid_get_tag_value(conf->blkid_cache, "TYPE", ev->devnode);
if (searchdev != NULL) { if (strncmp("LABEL=", searchdev, 6) == 0) {- label = blkid_get_tag_value(cache, "LABEL", ev->devnode);
+ label = blkid_get_tag_value(conf->blkid_cache, "LABEL", ev->devnode);
if (label && strcmp(label, searchdev+6) == 0)
rc = FOUND_DEVICE;
} else if (strncmp("UUID=", searchdev, 5) == 0) {- uuid = blkid_get_tag_value(cache, "UUID", ev->devnode);
+ uuid = blkid_get_tag_value(conf->blkid_cache, "UUID", ev->devnode);
if (uuid && strcmp(uuid, searchdev+5) == 0)
rc = FOUND_DEVICE;
}
@@ -784,8 +816,9 @@
return rc;
}
-static void handle_uevent(struct ueventconf *conf, struct uevent *ev)
+static void uevent_handle(struct uevent *ev)
{+ struct ueventconf *conf = ev->conf;
int found;
if (!ev->subsystem || strcmp(ev->subsystem, "block") != 0)
@@ -810,17 +843,26 @@
}
}
-static int dispatch_uevent(struct uevent *ev, struct ueventconf *conf)
+static void uevent_mdev_done_cb(void *ctx, int status)
{+ struct uevent *ev = ctx;
+ uevent_handle(ev);
+ uevent_unref(ev);
+}
+
+static void uevent_dispatch(struct uevent *ev)
+{+ struct ueventconf *conf = ev->conf;
+
if (conf->subsystem_filter && ev->subsystem
&& strcmp(ev->subsystem, conf->subsystem_filter) != 0) { dbg("subsystem '%s' filtered out (by '%s').",ev->subsystem, conf->subsystem_filter);
- return 0;
+ return;
}
if (ev->action == NULL)
- return 0;
+ return;
dbg("uevent: action='%s' subsystem='%s' devname='%s'",ev->action, ev->subsystem, ev->devname);
@@ -837,36 +879,41 @@
} else if (ev->devname != NULL) { if (conf->program_argv[0] != NULL) {- spawn_command(&spawnmgr, conf->program_argv, ev->envp);
+ spawn_command_cb(&spawnmgr, conf->program_argv, ev->envp,
+ uevent_mdev_done_cb, uevent_ref(ev));
conf->fork_count++;
+ } else {+ uevent_handle(ev);
}
- handle_uevent(conf, ev);
}
- return 0;
}
-static int process_uevent(char *buf, const size_t len, struct ueventconf *conf)
+static void uevent_process(char *buf, const size_t len, struct ueventconf *conf)
{- struct uevent ev;
-
+ struct uevent *ev;
int i, nenvp, slen = 0;
char *key, *value;
- memset(&ev, 0, sizeof(ev));
- ev.buf = buf;
- ev.bufsize = len;
+ ev = malloc(len + sizeof *ev);
+ if (!ev) return;
+ memset(ev, 0, sizeof *ev);
+ memcpy(ev->buf, buf, len);
+ ev->ref = 1;
+ ev->conf = conf;
+ ev->bufsize = len;
+
nenvp = sizeof(default_envp) / sizeof(default_envp[0]) - 1;
- memcpy(&ev.envp, default_envp, nenvp * sizeof(default_envp[0]));
+ memcpy(&ev->envp, default_envp, nenvp * sizeof(default_envp[0]));
for (i = 0; i < len; i += slen + 1) {- key = buf + i;
+ key = ev->buf + i;
value = strchr(key, '=');
- slen = strlen(buf+i);
+ slen = strlen(ev->buf + i);
if (i == 0 && slen != 0) {/* first line, the message */
- ev.message = key;
+ ev->message = key;
continue;
}
@@ -875,25 +922,26 @@
value++;
if (envcmp(key, "MODALIAS")) {- ev.modalias = value;
+ ev->modalias = value;
} else if (envcmp(key, "ACTION")) {- ev.action = value;
+ ev->action = value;
} else if (envcmp(key, "SUBSYSTEM")) {- ev.subsystem = value;
+ ev->subsystem = value;
} else if (envcmp(key, "DEVNAME")) {- ev.devname = value;
+ ev->devname = value;
} else if (envcmp(key, "MAJOR")) {- ev.major = value;
+ ev->major = value;
} else if (envcmp(key, "MINOR")) {- ev.minor = value;
+ ev->minor = value;
}
if (!envcmp(key, "PATH"))
- ev.envp[nenvp++]= key;
+ ev->envp[nenvp++]= key;
}
- ev.envp[nenvp++] = 0;
+ ev->envp[nenvp++] = 0;
- return dispatch_uevent(&ev, conf);
+ uevent_dispatch(ev);
+ uevent_unref(ev);
}
static void trigger_uevent_cb(const char *path, const void *data)
@@ -1085,7 +1133,7 @@
continue;
event_count++;
- process_uevent(buf, len, &conf);
+ uevent_process(buf, len, &conf);
}
if (fds[0].revents & POLLHUP) {@@ -1101,7 +1149,7 @@
while (read(fds[1].fd, &fdsi, sizeof fdsi) > 0)
;
while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
- spawn_reap(&spawnmgr, pid);
+ spawn_reap(&spawnmgr, pid, status);
}
if (fds[2].revents & POLLIN) {@@ -1121,6 +1169,7 @@
}
close(fds[2].fd);
pthread_mutex_destroy(&conf.cryptsetup_mutex);
+ if (conf.blkid_cache) blkid_put_cache(conf.blkid_cache);
dbg("modaliases: %i, forks: %i, events: %i, total bufsize: %zu",conf.modalias_count,