Set LOG_PID for syslog

[thirdparty/mdadm.git] / mdopen.c

diff --git a/mdopen.c b/mdopen.c
index ebaba950705bb2dc2ca7dab30b582b2dc453b0e5..448a9eb85eb49aec091558d1881c8182f41740f9 100644 (file)
--- a/mdopen.c
+++ b/mdopen.c
@@ -113,7 +113,6 @@ int open_mddev(char *dev, int autof)
        int major_num = MD_MAJOR;
        int minor_num = 0;
        int must_remove = 0;
-       struct mdstat_ent *mdlist;
        int num;
        struct createinfo *ci = conf_get_create_info();
        int parts;
@@ -193,41 +192,16 @@ int open_mddev(char *dev, int autof)
                 * If the device name is in a 'standard' format,
                 * intuit the minor from that, else
                 * easiest to read /proc/mdstat, and hunt through for
-                * an unused number 
+                * an unused number
                 */
                if (num < 0) {
                        /* need to pick an unused number */
-                       mdlist = mdstat_read(0, 0);
-                       /* Choose a large number.  Start from 127 and search down,
-                        * but if nothing is found, start really big
-                        */
-                       for (num = 127 ; num != 128 ; num = num ? num-1 : (1<<22)-1) {
-                               struct mdstat_ent *me;
-                               int devnum = num;
-                               if (major_num != MD_MAJOR)
-                                       devnum = -1-num;
+                       int num = find_free_devnum(major_num != MD_MAJOR);
 
-                               for (me=mdlist; me; me=me->next)
-                                       if (me->devnum == devnum)
-                                               break;
-                               if (!me) {
-                                       /* doesn't exist in mdstat.
-                                        * make sure it is new to /dev too
-                                        */
-                                       char *dn;
-                                       if (major_num != MD_MAJOR)
-                                               minor_num = num << MdpMinorShift;
-                                       else
-                                               minor_num = num;
-                                       dn = map_dev(major_num,minor_num, 0);
-                                       if (dn==NULL || is_standard(dn, NULL)) {
-                                               /* this number only used by a 'standard' name,
-                                                * so it is safe to use
-                                                */
-                                               break;
-                                       }
-                               }
-                       }
+                       if (major_num == MD_MAJOR)
+                               minor_num = num;
+                       else
+                               minor_num = (-1-num) << MdpMinorShift;
                } else if (major_num == MD_MAJOR)
                        minor_num = num;
                else
@@ -294,7 +268,8 @@ int open_mddev(char *dev, int autof)
 }
 
 
-int open_mddev_devnum(char *devname, int devnum, char *name, char *chosen_name)
+int open_mddev_devnum(char *devname, int devnum, char *name,
+                     char *chosen_name, int parts)
 {
        /* Open the md device with number 'devnum', possibly using 'devname',
         * possibly constructing a name with 'name', but in any case, copying
@@ -302,6 +277,8 @@ int open_mddev_devnum(char *devname, int devnum, char *name, char *chosen_name)
         */
        int major_num, minor_num;
        struct stat stb;
+       int i;
+       struct createinfo *ci = conf_get_create_info();
 
        if (devname)
                strcpy(chosen_name, devname);
@@ -333,11 +310,39 @@ int open_mddev_devnum(char *devname, int devnum, char *name, char *chosen_name)
                        return -1;
                }
        } else {
+               /* special case: if --incremental is suggesting a name
+                * in /dev/md/, we make sure the directory exists.
+                */
+               if (strncmp(chosen_name, "/dev/md/", 8) == 0) {
+                       if (mkdir("/dev/md",0700)==0) {
+                               if (chown("/dev/md", ci->uid, ci->gid))
+                                       perror("chown /dev/md");
+                               if (chmod("/dev/md", ci->mode|
+                                                 ((ci->mode>>2) & 0111)))
+                                       perror("chmod /dev/md");
+                       }
+               }
+
                if (mknod(chosen_name, S_IFBLK | 0600,
                          makedev(major_num, minor_num)) != 0) {
                        return -1;
                }
                /* FIXME chown/chmod ?? */
        }
-       return open(chosen_name, O_RDWR);
+
+       /* Simple locking to avoid --incr being called for the same
+        * array multiple times in parallel.
+        */
+       for (i = 0; i < 25 ; i++) {
+               int fd;
+
+               fd = open(chosen_name, O_RDWR|O_EXCL);
+               if (fd >= 0 || errno != EBUSY) {
+                       if (devnum < 0)
+                               make_parts(chosen_name, parts, ci->symlinks);
+                       return fd;
+               }
+               usleep(200000);
+       }
+       return -1;
 }