mdadm: improve the dlm locking mechanism for clustered raid

[thirdparty/mdadm.git] / mdadm.c

diff --git a/mdadm.c b/mdadm.c
index afc3015144d3f581dc1024405296c0747c34e7f0..5afe4155d7011f2f3b653ff162dedeb940cdd911 100644 (file)
--- a/mdadm.c
+++ b/mdadm.c
@@ -57,6 +57,7 @@ int main(int argc, char *argv[])
        struct mddev_dev *devlist = NULL;
        struct mddev_dev **devlistend = & devlist;
        struct mddev_dev *dv;
+       mdu_array_info_t array;
        int devs_found = 0;
        char *symlinks = NULL;
        int grow_continue = 0;
@@ -103,6 +104,7 @@ int main(int argc, char *argv[])
        FILE *outf;
 
        int mdfd = -1;
+       int locked = 0;
 
        srandom(time(0) ^ getpid());
 
@@ -1434,6 +1436,22 @@ int main(int argc, char *argv[])
                /* --scan implied --brief unless -vv */
                c.brief = 1;
 
+       if (mode == CREATE) {
+               if (s.bitmap_file && strcmp(s.bitmap_file, "clustered") == 0) {
+                       locked = cluster_get_dlmlock();
+                       if (locked != 1)
+                               exit(1);
+               }
+       } else if (mode == MANAGE || mode == GROW || mode == INCREMENTAL) {
+               if (!md_get_array_info(mdfd, &array) && (devmode != 'c')) {
+                       if (array.state & (1 << MD_SB_CLUSTERED)) {
+                               locked = cluster_get_dlmlock();
+                               if (locked != 1)
+                                       exit(1);
+                       }
+               }
+       }
+
        switch(mode) {
        case MANAGE:
                /* readonly, add/remove, readwrite, runstop */
@@ -1739,6 +1757,8 @@ int main(int argc, char *argv[])
                autodetect();
                break;
        }
+       if (locked)
+               cluster_release_dlmlock();
        if (mdfd > 0)
                close(mdfd);
        exit(rv);