]> git.ipfire.org Git - thirdparty/mdadm.git/blobdiff - mdmon.c
mdmon: Document startup/shutdown requirements in man page.
[thirdparty/mdadm.git] / mdmon.c
diff --git a/mdmon.c b/mdmon.c
index 37474603ee6cce0a4c14564301cadf4bae0fac24..31d45fd5662b046ba9e967cf48fb82c276f69443 100644 (file)
--- a/mdmon.c
+++ b/mdmon.c
@@ -113,7 +113,7 @@ static struct superswitch *find_metadata_methods(char *vers)
        return NULL;
 }
 
-int make_pidfile(char *devname)
+static int make_pidfile(char *devname)
 {
        char path[100];
        char pid[10];
@@ -192,7 +192,7 @@ void remove_pidfile(char *devname)
                rmdir(pid_dir);
 }
 
-int make_control_sock(char *devname)
+static int make_control_sock(char *devname)
 {
        char path[100];
        int sfd;
@@ -221,12 +221,6 @@ int make_control_sock(char *devname)
        return sfd;
 }
 
-int socket_hup_requested;
-static void hup(int sig)
-{
-       socket_hup_requested = 1;
-}
-
 static void term(int sig)
 {
        sigterm = 1;
@@ -254,28 +248,31 @@ void usage(void)
        exit(2);
 }
 
-static int mdmon(char *devname, int devnum, int must_fork, char *switchroot);
+static int mdmon(char *devname, int devnum, int must_fork, int takeover);
 
 int main(int argc, char *argv[])
 {
        char *container_name = NULL;
-       char *switchroot = NULL;
        int devnum;
        char *devname;
        int status = 0;
-
-       switch (argc) {
-       case 3:
-               switchroot = argv[2];
-       case 2:
-               container_name = argv[1];
-               break;
-       default:
-               usage();
+       int arg;
+       int all = 0;
+       int takeover = 0;
+
+       for (arg = 1; arg < argc; arg++) {
+               if (strcmp(argv[arg], "--all") == 0 ||
+                   strcmp(argv[arg], "/proc/mdstat") == 0)
+                       all = 1;
+               else if (strcmp(argv[arg], "--takeover") == 0)
+                       takeover = 1;
+               else if (container_name == NULL)
+                       container_name = argv[arg];
+               else
+                       usage();
        }
 
-       if (strcmp(container_name, "/proc/mdstat") == 0 ||
-           strcmp(container_name, "--all") == 0) {
+       if (all) {
                struct mdstat_ent *mdstat, *e;
 
                /* launch an mdmon instance for each container found */
@@ -292,7 +289,7 @@ int main(int argc, char *argv[])
                                        sprintf(container_name, "%s", devname);
                                }
                                status |= mdmon(devname, e->devnum, 1,
-                                               switchroot);
+                                               takeover);
                        }
                }
                free_mdstat(mdstat);
@@ -320,10 +317,10 @@ int main(int argc, char *argv[])
                        container_name);
                exit(1);
        }
-       return mdmon(devname, devnum, do_fork(), switchroot);
+       return mdmon(devname, devnum, do_fork(), takeover);
 }
 
-static int mdmon(char *devname, int devnum, int must_fork, char *switchroot)
+static int mdmon(char *devname, int devnum, int must_fork, int takeover)
 {
        int mdfd;
        struct mdinfo *mdi, *di;
@@ -336,50 +333,7 @@ static int mdmon(char *devname, int devnum, int must_fork, char *switchroot)
        pid_t victim = -1;
        int victim_sock = -1;
 
-       dprintf("starting mdmon for %s in %s\n",
-               devname, switchroot ? : "/");
-
-       /* switchroot is either a path name starting with '/', or a
-        * pid of the original mdmon (we have already done the chroot).
-        * In the latter case, stdin is a socket connected to the original
-        * mdmon.
-        */
-
-       /* try to spawn mdmon instances from the target file system */
-       if (switchroot && switchroot[0] == '/' &&
-           strcmp(switchroot, "/") != 0) {
-               pid_t pid;
-               char buf[20];
-
-               switch (fork()) {
-               case 0:
-                       victim = mdmon_pid(devnum);
-                       victim_sock = connect_monitor(devname);
-                       if (chroot(switchroot) != 0) {
-                               fprintf(stderr, "mdmon: failed to chroot to '%s': %s\n",
-                                       switchroot, strerror(errno));
-                               exit(4);
-                       }
-                       ignore = chdir("/");
-                       sprintf(buf, "%d", victim);
-                       if (victim_sock) {
-                               close(0);
-                               dup(victim_sock);
-                               close(victim_sock);
-                       }
-                       execl("/sbin/mdmon", "mdmon", devname, buf, NULL);
-                       exit(1);
-               case -1:
-                       return 1;
-               default:
-                       pid = wait(&status);
-                       if (pid > -1 && WIFEXITED(status) &&
-                           WEXITSTATUS(status) == 0)
-                               return 0;
-                       else
-                               return 1;
-               }
-       }
+       dprintf("starting mdmon for %s\n", devname);
 
        mdfd = open_dev(devnum);
        if (mdfd < 0) {
@@ -471,32 +425,25 @@ static int mdmon(char *devname, int devnum, int must_fork, char *switchroot)
         */
        sigemptyset(&set);
        sigaddset(&set, SIGUSR1);
-       sigaddset(&set, SIGHUP);
-       sigaddset(&set, SIGALRM);
        sigaddset(&set, SIGTERM);
        sigprocmask(SIG_BLOCK, &set, NULL);
        act.sa_handler = wake_me;
        act.sa_flags = 0;
        sigaction(SIGUSR1, &act, NULL);
-       sigaction(SIGALRM, &act, NULL);
-       act.sa_handler = hup;
-       sigaction(SIGHUP, &act, NULL);
        act.sa_handler = term;
        sigaction(SIGTERM, &act, NULL);
        act.sa_handler = SIG_IGN;
        sigaction(SIGPIPE, &act, NULL);
 
-       if (switchroot) {
-               /* we assume we assume that /sys /proc /dev are available in
-                * the new root
-                */
-               if (switchroot[0] == '/') {
+       if (takeover) {
+               pid_dir = VAR_RUN;
+               victim = mdmon_pid(container->devnum);
+               if (victim < 0) {
+                       pid_dir = ALT_RUN;
                        victim = mdmon_pid(container->devnum);
-                       victim_sock = connect_monitor(container->devname);
-               } else {
-                       victim = atoi(switchroot);
-                       victim_sock = 0;
                }
+               if (victim >= 0)
+                       victim_sock = connect_monitor(container->devname);
        }
 
        ignore = chdir("/");
@@ -518,6 +465,25 @@ static int mdmon(char *devname, int devnum, int must_fork, char *switchroot)
 
        /* Ok, this is close enough.  We can say goodbye to our parent now.
         */
+       if (victim > 0)
+               remove_pidfile(devname);
+       if (mkdir(VAR_RUN, 0600) >= 0 || errno == EEXIST)
+               pid_dir = VAR_RUN;
+       else if (mkdir(ALT_RUN, 0600) >= 0 || errno == EEXIST)
+               pid_dir = ALT_RUN;
+       else {
+               fprintf(stderr, "mdmon: Neither %s nor %s are writable\n"
+                       "       cannot create .pid or .sock files.  Aborting\n",
+                       VAR_RUN, ALT_RUN);
+               exit(3);
+       }
+       if (make_pidfile(devname) < 0) {
+               fprintf(stderr, "mdmon: Cannot create pid file in %s - aborting.\n",
+                       pid_dir);
+               exit(3);
+       }
+       container->sock = make_control_sock(devname);
+
        status = 0;
        if (write(pfd[1], &status, sizeof(status)) < 0)
                fprintf(stderr, "mdmon: failed to notify our parent: %d\n",
@@ -532,7 +498,7 @@ static int mdmon(char *devname, int devnum, int must_fork, char *switchroot)
                exit(2);
        }
 
-       if (victim > -1) {
+       if (victim > 0) {
                try_kill_monitor(victim, container->devname, victim_sock);
                close(victim_sock);
        }