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@xxxxxxxxxx>
---
libmultipath/discovery.c | 3 +-
libmultipath/wwids.c | 130 +++++++++++++++++++++++++++++++++++++++++++++++
libmultipath/wwids.h | 2 +
multipath/main.c | 51 +++++++++++++++++--
multipath/multipath.8 | 8 ++-
5 files changed, 188 insertions(+), 6 deletions(-)
diff --git a/libmultipath/discovery.c b/libmultipath/discovery.c
index 826ea75..4d452a1 100644
--- a/libmultipath/discovery.c
+++ b/libmultipath/discovery.c
@@ -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;
diff --git a/libmultipath/wwids.c b/libmultipath/wwids.c
index abd23c5..91b07a7 100644
--- a/libmultipath/wwids.c
+++ b/libmultipath/wwids.c
@@ -82,6 +82,136 @@ write_out_wwid(int fd, char *wwid) {
}
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)
{
int fd, can_write, found, ret;
diff --git a/libmultipath/wwids.h b/libmultipath/wwids.h
index 1678f9d..f3b21fa 100644
--- a/libmultipath/wwids.h
+++ b/libmultipath/wwids.h
@@ -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 */
diff --git a/multipath/main.c b/multipath/main.c
index 3038869..f1b3ec9 100644
--- a/multipath/main.c
+++ b/multipath/main.c
@@ -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);
diff --git a/multipath/multipath.8 b/multipath/multipath.8
index afaa6c4..a2262ac 100644
--- a/multipath/multipath.8
+++ b/multipath/multipath.8
@@ -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
--
1.8.2
--
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