auto-start mdmon on --create

FIXME uses sill hardcoded path.

Need --assemble too.

diff --git a/Create.c b/Create.c
index ee73548ddd541c5b07f1f4ef0dd591d1d8b21e8b..59a41a66aff5a2e6b3b6dcde4d64e0e9b23deda4 100644 (file)
--- a/Create.c
+++ b/Create.c
@@ -71,6 +71,8 @@ int Create(struct supertype *st, char *mddev, int mdfd,
        int rv;
        int bitmap_fd;
        int have_container = 0;
+       int container_fd;
+       int need_mdmon = 0;
        unsigned long long bitmapsize;
        struct mdinfo *sra;
        struct mdinfo info;
@@ -545,6 +547,31 @@ int Create(struct supertype *st, char *mddev, int mdfd,
                        sprintf(ver, "external:/%s/%d",
                                devnum2devname(st->container_dev),
                                st->container_member);
+                       /* When creating a member, we need to be careful
+                        * to negotiate with mdmon properly.
+                        * If it is already running, we cannot write to
+                        * the devices and must ask it to do that part.
+                        * If it isn't running, we write to the devices,
+                        * and then start it.
+                        * We hold an exclusive open on the container
+                        * device to make sure mdmon doesn't exit after
+                        * we checked that it is running.
+                        *
+                        * For now, fail if it is already running.
+                        */
+                       container_fd = open_dev_excl(st->container_dev);
+                       if (container_fd < 0) {
+                               fprintf(stderr, Name ": Cannot get exclusive "
+                                       "open on container - weird.\n");
+                               return 1;
+                       }
+                       if (mdmon_running(st->container_dev)) {
+                               fprintf(stderr, Name ": mdmon already running "
+                                       "for %s - sorry\n",
+                                       devnum2devname(st->container_dev));
+                               return 1;
+                       }
+                       need_mdmon = 1;
                }
                if ((vers % 100) < 2 ||
                    sra == NULL ||
@@ -681,6 +708,7 @@ int Create(struct supertype *st, char *mddev, int mdfd,
                        case 0:
                                sysfs_set_str(sra, NULL, "array_state",
                                              "active");
+                               need_mdmon = 0;
                                break;
                        default:
                                sysfs_set_str(sra, NULL, "array_state",
@@ -698,6 +726,31 @@ int Create(struct supertype *st, char *mddev, int mdfd,
                }
                if (verbose >= 0)
                        fprintf(stderr, Name ": array %s started.\n", mddev);
+               if (st->ss->external == 2) {
+                       if (need_mdmon) {
+                               int dn = st->container_dev;
+                               int i;
+                               switch(fork()) {
+                               case 0:
+                                       /* FIXME yuk. CLOSE_EXEC?? */
+                                       for (i=3; i < 100; i++)
+                                               close(i);
+                                       execl("./mdmon", "mdmon",
+                                             map_dev(dev2major(dn),
+                                                     dev2minor(dn),
+                                                     1), NULL);
+                                       exit(1);
+                               case -1: fprintf(stderr, Name ": cannot fork. "
+                                                "Array remains readonly\n");
+                                       return 1;
+                               default: ; /* parent - good */
+                               }
+                       } else
+                               signal_mdmon(st->container_dev);
+                       /* FIXME wait for mdmon to set array to read-auto */
+                       sleep(1);
+                       close(container_fd);
+               }
        } else {
                fprintf(stderr, Name ": not starting array - not enough devices.\n");
        }

diff --git a/mdadm.h b/mdadm.h
index 5586dce47b593088b9a967e1fa99daf5a2f2dada..bf7e2967de704c411b5ba6c654165c7e59a5995e 100644 (file)
--- a/mdadm.h
+++ b/mdadm.h
@@ -584,6 +584,7 @@ extern int check_raid(int fd, char *name);
 
 extern int get_mdp_major(void);
 extern int dev_open(char *dev, int flags);
+extern int open_dev_excl(int devnum);
 extern int is_standard(char *dev, int *nump);
 
 extern int parse_auto(char *str, char *msg, int config);
@@ -629,9 +630,27 @@ extern int open_mddev_devnum(char *devname, int devnum, char *name,
                             char *chosen_name, int parts);
 extern int open_container(int fd);
 
+extern int mdmon_running(int devnum);
+extern int signal_mdmon(int devnum);
+
 extern char *devnum2devname(int num);
 extern int fd2devnum(int fd);
 
+static inline int dev2major(int d)
+{
+       if (d >= 0)
+               return MD_MAJOR;
+       else
+               return get_mdp_major();
+}
+
+static inline int dev2minor(int d)
+{
+       if (d >= 0)
+               return d;
+       return (-1-d) << MdpMinorShift;
+}
+
 #define        LEVEL_MULTIPATH         (-4)
 #define        LEVEL_LINEAR            (-1)
 #define        LEVEL_FAULTY            (-5)

diff --git a/util.c b/util.c
index d026c3026430f1098aa7604816485be347e63d52..6f1620a6132fb51e169e5005693e6e7926173990 100644 (file)
--- a/util.c
+++ b/util.c
@@ -32,6 +32,7 @@
 #include       <sys/utsname.h>
 #include       <ctype.h>
 #include       <dirent.h>
+#include       <signal.h>
 
 /*
  * following taken from linux/blkpg.h because they aren't
@@ -714,21 +715,6 @@ void put_md_name(char *name)
                unlink(name);
 }
 
-static int dev2major(int d)
-{
-       if (d >= 0)
-               return MD_MAJOR;
-       else
-               return get_mdp_major();
-}
-
-static int dev2minor(int d)
-{
-       if (d >= 0)
-               return d;
-       return (-1-d) << MdpMinorShift;
-}
-
 int find_free_devnum(int use_partitions)
 {
        int devnum;
@@ -781,6 +767,23 @@ int dev_open(char *dev, int flags)
        return fd;
 }
 
+int open_dev_excl(int devnum)
+{
+       char buf[20];
+       int i;
+
+       sprintf(buf, "%d:%d", dev2major(devnum), dev2minor(devnum));
+       for (i=0 ; i<25 ; i++) {
+               int fd = dev_open(buf, O_RDWR|O_EXCL);
+               if (fd >= 0)
+                       return fd;
+               if (errno != EBUSY)
+                       return fd;
+               usleep(200000);
+       }
+       return -1;
+}
+
 struct superswitch *superlist[] = { &super0, &super1, &super_ddf, &super_imsm, NULL };
 
 #if !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO)
@@ -1009,6 +1012,48 @@ int fd2devnum(int fd)
        return -1;
 }
 
+int mdmon_running(int devnum)
+{
+       char path[100];
+       char pid[10];
+       int fd;
+       int n;
+       sprintf(path, "/var/run/mdadm/%s.pid", devnum2devname(devnum));
+       fd = open(path, O_RDONLY, 0);
+
+       if (fd < 0)
+               return 0;
+       n = read(fd, pid, 9);
+       close(fd);
+       if (n <= 0)
+               return 0;
+       if (kill(atoi(pid), 0) == 0)
+               return 1;
+       return 0;
+}
+
+int signal_mdmon(int devnum)
+{
+       char path[100];
+       char pid[10];
+       int fd;
+       int n;
+       sprintf(path, "/var/run/mdadm/%s.pid", devnum2devname(devnum));
+       fd = open(path, O_RDONLY, 0);
+
+       if (fd < 0)
+               return 0;
+       n = read(fd, pid, 9);
+       close(fd);
+       if (n <= 0)
+               return 0;
+       if (kill(atoi(pid), SIGUSR1) == 0)
+               return 1;
+       return 0;
+}
+
+
+
 #ifdef __TINYC__
 /* tinyc doesn't optimize this check in ioctl.h out ... */
 unsigned int __invalid_size_argument_for_IOC = 0;