From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Marzinski Subject: [PATCH v2] multipath: make devt2devname use lstat to check sysfs links Date: Thu, 10 Jan 2013 14:06:19 -0600 Message-ID: <20130110200619.GP19059@ether.msp.redhat.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: device-mapper development Cc: Christophe Varoqui List-Id: dm-devel.ids dm_reassign wasn't working correctly for me because devt2devname used stat() to check if /sys/dev/block/major:minor was a symlink. But stat() never returns a symlink, if follows it. It needs to use lstat() instead. Also, I made multipath log a message when a dm device gets reassigned to use multipath. Signed-off-by: Benjamin Marzinski --- libmultipath/devmapper.c | 4 +++- libmultipath/sysfs.c | 6 ++++-- libmultipath/util.c | 3 ++- 3 files changed, 9 insertions(+), 4 deletions(-) Index: multipath-tools-130109/libmultipath/devmapper.c =================================================================== --- multipath-tools-130109.orig/libmultipath/devmapper.c +++ multipath-tools-130109/libmultipath/devmapper.c @@ -1394,8 +1394,10 @@ int dm_reassign(const char *mapname) return 1; } - if (!(dmt = dm_task_create(DM_DEVICE_DEPS))) + if (!(dmt = dm_task_create(DM_DEVICE_DEPS))) { + condlog(3, "%s: couldn't make dm task", mapname); return 0; + } if (!dm_task_set_name(dmt, mapname)) goto out; Index: multipath-tools-130109/libmultipath/sysfs.c =================================================================== --- multipath-tools-130109.orig/libmultipath/sysfs.c +++ multipath-tools-130109/libmultipath/sysfs.c @@ -125,8 +125,10 @@ int sysfs_check_holders(char * check_dev return 0; } - if (devt2devname(check_dev, PATH_SIZE, check_devt)) + if (devt2devname(check_dev, PATH_SIZE, check_devt)) { + condlog(1, "can't get devname for %s", check_devt); return 0; + } condlog(3, "%s: checking holder", check_dev); @@ -153,7 +155,7 @@ int sysfs_check_holders(char * check_dev } table_name = dm_mapname(major, table_minor); - condlog(3, "%s: reassign table %s old %s new %s", check_dev, + condlog(0, "%s: reassign table %s old %s new %s", check_dev, table_name, check_devt, new_devt); dm_reassign_table(table_name, check_devt, new_devt); Index: multipath-tools-130109/libmultipath/util.c =================================================================== --- multipath-tools-130109.orig/libmultipath/util.c +++ multipath-tools-130109/libmultipath/util.c @@ -161,6 +161,7 @@ devt2devname (char *devname, int devname struct stat statbuf; memset(block_path, 0, sizeof(block_path)); + memset(dev, 0, sizeof(dev)); if (sscanf(devt, "%u:%u", &major, &minor) != 2) { condlog(0, "Invalid device number %s", devt); return 1; @@ -172,7 +173,7 @@ devt2devname (char *devname, int devname if (stat("/sys/dev/block", &statbuf) == 0) { /* Newer kernels have /sys/dev/block */ sprintf(block_path,"/sys/dev/block/%u:%u", major, minor); - if (stat(block_path, &statbuf) == 0) { + if (lstat(block_path, &statbuf) == 0) { if (S_ISLNK(statbuf.st_mode) && readlink(block_path, dev, FILE_NAME_SIZE) > 0) { char *p = strrchr(dev, '/');