add wwids file cleanup options
authorBenjamin Marzinski <bmarzins@redhat.com>
Thu, 2 May 2013 21:46:31 +0000 (16:46 -0500)
committerChristophe Varoqui <christophe.varoqui@opensvc.com>
Mon, 6 May 2013 19:41:15 +0000 (21:41 +0200)
This patch adds the "-w <device>" and "-W" options to multipath. They
allow users to either remove a specified device from the wwids file, or
reset the wwids file to only include the wwids for their current
multipath devices.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
libmultipath/discovery.c
libmultipath/wwids.c
libmultipath/wwids.h
multipath/main.c
multipath/multipath.8

index 826ea75..4d452a1 100644 (file)
@@ -53,7 +53,8 @@ store_pathinfo (vector pathvec, vector hwtable, struct udev_device *udevice,
                goto out;
        }
        pp->udev = udev_device_ref(udevice);
-       err = pathinfo(pp, hwtable, flag | DI_BLACKLIST);
+       err = pathinfo(pp, hwtable,
+                      (conf->dry_run == 3)? flag : (flag | DI_BLACKLIST));
        if (err)
                goto out;
 
index abd23c5..91b07a7 100644 (file)
@@ -81,6 +81,136 @@ write_out_wwid(int fd, char *wwid) {
        return 1;
 }
 
+int
+replace_wwids(vector mp)
+{
+       int i, fd, can_write;
+       struct multipath * mpp;
+       size_t len;
+       int ret = -1;
+
+       fd = open_file(conf->wwids_file, &can_write, WWIDS_FILE_HEADER);
+       if (fd < 0)
+               goto out;
+       if (!can_write) {
+               condlog(0, "cannot replace wwids. wwids file is read-only");
+               goto out_file;
+       }
+       if (ftruncate(fd, 0) < 0) {
+               condlog(0, "cannot truncate wwids file : %s", strerror(errno));
+               goto out_file;
+       }
+       len = strlen(WWIDS_FILE_HEADER);
+       if (write_all(fd, WWIDS_FILE_HEADER, len) != len) {
+               condlog(0, "Can't write wwid file header : %s",
+                       strerror(errno));
+               /* cleanup partially written header */
+               if (ftruncate(fd, 0) < 0)
+                       condlog(0, "Cannot truncate header : %s",
+                               strerror(errno));
+               goto out_file;
+       }
+       if (!mp || !mp->allocated) {
+               ret = 0;
+               goto out_file;
+       }
+       vector_foreach_slot(mp, mpp, i) {
+               if (write_out_wwid(fd, mpp->wwid) < 0)
+                       goto out_file;
+       }
+       ret = 0;
+out_file:
+       close(fd);
+out:
+       return ret;
+}
+
+int
+do_remove_wwid(int fd, char *str) {
+       char buf[4097];
+       char *ptr;
+       off_t start = 0;
+       int bytes;
+
+       while (1) {
+               if (lseek(fd, start, SEEK_SET) < 0) {
+                       condlog(0, "wwid file read lseek failed : %s",
+                               strerror(errno));
+                       return -1;
+               }
+               bytes = read(fd, buf, 4096);
+               if (bytes < 0) {
+                       if (errno == EINTR || errno == EAGAIN)
+                               continue;
+                       condlog(0, "failed to read from wwids file : %s",
+                               strerror(errno));
+                       return -1;
+               }
+               if (!bytes) /* didn't find wwid to remove */
+                       return 1;
+               buf[bytes] = '\0';
+               ptr = strstr(buf, str);
+               if (ptr != NULL) {
+                       condlog(3, "found '%s'", str);
+                       if (lseek(fd, start + (ptr - buf), SEEK_SET) < 0) {
+                               condlog(0, "write lseek failed : %s",
+                                               strerror(errno));
+                               return -1;
+                       }
+                       while (1) {
+                               if (write(fd, "#", 1) < 0) {
+                                       if (errno == EINTR || errno == EAGAIN)
+                                               continue;
+                                       condlog(0, "failed to write to wwids file : %s", strerror(errno));
+                                       return -1;
+                               }
+                               return 0;
+                       }
+               }
+               ptr = strrchr(buf, '\n');
+               if (ptr == NULL) { /* shouldn't happen, assume it is EOF */
+                       condlog(4, "couldn't find newline, assuming end of file");
+                       return 1;
+               }
+               start = start + (ptr - buf) + 1;
+       }
+}
+
+
+int
+remove_wwid(char *wwid) {
+       int fd, len, can_write;
+       char *str;
+       int ret = -1;
+
+       len = strlen(wwid) + 4; /* two slashes the newline and a zero byte */
+       str = malloc(len);
+       if (str == NULL) {
+               condlog(0, "can't allocate memory to remove wwid : %s",
+                       strerror(errno));
+               return -1;
+       }
+       if (snprintf(str, len, "/%s/\n", wwid) >= len) {
+               condlog(0, "string overflow trying to remove wwid");
+               goto out;
+       }
+       condlog(3, "removing line '%s' from wwids file", str);
+       fd = open_file(conf->wwids_file, &can_write, WWIDS_FILE_HEADER);
+       if (fd < 0)
+               goto out;
+       if (!can_write) {
+               condlog(0, "cannot remove wwid. wwids file is read-only");
+               goto out_file;
+       }
+       ret = do_remove_wwid(fd, str);
+
+out_file:
+       close(fd);
+out:
+       free(str);
+       return ret;
+}
+
 int
 check_wwids_file(char *wwid, int write_wwid)
 {
index 1678f9d..f3b21fa 100644 (file)
@@ -14,5 +14,7 @@
 
 int remember_wwid(char *wwid);
 int check_wwids_file(char *wwid, int write_wwid);
+int remove_wwid(char *wwid);
+int replace_wwids(vector mp);
 
 #endif /* _WWIDS_H */
index 3038869..f1b3ec9 100644 (file)
@@ -83,7 +83,7 @@ usage (char * progname)
 {
        fprintf (stderr, VERSION_STRING);
        fprintf (stderr, "Usage:\n");
-       fprintf (stderr, "  %s [-c] [-d] [-r] [-v lvl] [-p pol] [-b fil] [-q] [dev]\n", progname);
+       fprintf (stderr, "  %s [-c|-w|-W] [-d] [-r] [-v lvl] [-p pol] [-b fil] [-q] [dev]\n", progname);
        fprintf (stderr, "  %s -l|-ll|-f [-v lvl] [-b fil] [dev]\n", progname);
        fprintf (stderr, "  %s -F [-v lvl]\n", progname);
        fprintf (stderr, "  %s -t\n", progname);
@@ -104,6 +104,8 @@ usage (char * progname)
                "  -B      treat the bindings file as read only\n" \
                "  -p      policy failover|multibus|group_by_serial|group_by_prio\n" \
                "  -b fil  bindings file location\n" \
+               "  -w      remove a device from the wwids file\n" \
+               "  -W      reset the wwids file include only the current devices\n" \
                "  -p pol  force all maps to specified path grouping policy :\n" \
                "          . failover            one path per priority group\n" \
                "          . multibus            all paths in one priority group\n" \
@@ -212,7 +214,6 @@ get_dm_mpvec (vector curmp, vector pathvec, char * refwwid)
 
                if (!conf->dry_run)
                        reinstate_paths(mpp);
-               remember_wwid(mpp->wwid);
        }
        return 0;
 }
@@ -262,7 +263,7 @@ configure (void)
        /*
         * if we have a blacklisted device parameter, exit early
         */
-       if (dev && conf->dev_type == DEV_DEVNODE &&
+       if (dev && conf->dev_type == DEV_DEVNODE && conf->dry_run != 3 &&
            (filter_devnode(conf->blist_devnode,
                            conf->elist_devnode, dev) > 0)) {
                if (conf->dry_run == 2)
@@ -284,6 +285,17 @@ configure (void)
                                condlog(3, "scope is nul");
                        goto out;
                }
+               if (conf->dry_run == 3) {
+                       r = remove_wwid(refwwid);
+                       if (r == 0)
+                               printf("wwid '%s' removed\n", refwwid);
+                       else if (r == 1) {
+                               printf("wwid '%s' not in wwids file\n",
+                                       refwwid);
+                               r = 0;
+                       }
+                       goto out;
+               }
                condlog(3, "scope limited to %s", refwwid);
                if (conf->dry_run == 2) {
                        if (check_wwids_file(refwwid, 0) == 0){
@@ -439,7 +451,7 @@ main (int argc, char *argv[])
        if (load_config(DEFAULT_CONFIGFILE))
                exit(1);
 
-       while ((arg = getopt(argc, argv, ":dchl::FfM:v:p:b:Brtq")) != EOF ) {
+       while ((arg = getopt(argc, argv, ":dchl::FfM:v:p:b:BrtqwW")) != EOF ) {
                switch(arg) {
                case 1: printf("optarg : %s\n",optarg);
                        break;
@@ -504,6 +516,12 @@ main (int argc, char *argv[])
                case 'h':
                        usage(argv[0]);
                        exit(0);
+               case 'w':
+                       conf->dry_run = 3;
+                       break;
+               case 'W':
+                       conf->dry_run = 4;
+                       break;
                case ':':
                        fprintf(stderr, "Missing option argument\n");
                        usage(argv[0]);
@@ -555,6 +573,31 @@ main (int argc, char *argv[])
                condlog(0, "the -c option requires a path to check");
                goto out;
        }
+       if (conf->dry_run == 3 && !conf->dev) {
+               condlog(0, "the -w option requires a device");
+               goto out;
+       }
+       if (conf->dry_run == 4) {
+               struct multipath * mpp;
+               int i;
+               vector curmp;
+
+               curmp = vector_alloc();
+               if (!curmp) {
+                       condlog(0, "can't allocate memory for mp list");
+                       goto out;
+               }
+               if (dm_get_maps(curmp) == 0)
+                       r = replace_wwids(curmp);
+               if (r == 0)
+                       printf("successfully reset wwids\n");
+               vector_foreach_slot_backwards(curmp, mpp, i) {
+                       vector_del_slot(curmp, i);
+                       free_multipath(mpp, KEEP_PATHS);
+               }
+               vector_free(curmp);
+               goto out;
+       }
        if (conf->remove == FLUSH_ONE) {
                if (conf->dev_type == DEV_DEVMAP) {
                        r = dm_suspend_and_flush_map(conf->dev);
index afaa6c4..a2262ac 100644 (file)
@@ -8,7 +8,7 @@ multipath \- Device mapper target autoconfig
 .RB [\| \-b\ \c
 .IR bindings_file \|]
 .RB [\| \-d \|]
-.RB [\| \-h | \-l | \-ll | \-f | \-t | \-F | \-B | \-c | \-q | \|-r \|]
+.RB [\| \-h | \-l | \-ll | \-f | \-t | \-F | \-B | \-c | \-q | \|-r | \-w | \-W \|]
 .RB [\| \-p\ \c
 .BR failover | multibus | group_by_serial | group_by_prio | group_by_node_name \|]
 .RB [\| device \|]
@@ -68,6 +68,12 @@ check if a block device should be a path in a multipath device
 .B \-q
 allow device tables with queue_if_no_path when multipathd is not running
 .TP
+.B \-w
+remove the wwid for the specified device from the wwids file
+.TP
+.B \-W
+reset the wwids file to only include the current multipath devices
+.TP
 .BI \-p " policy"
 force new maps to use the specified policy:
 .RS 1.2i