From ed002ed22adc61dfe477c3d42c9aae356f450d2c Mon Sep 17 00:00:00 2001 From: Peter Rajnoha Date: Tue, 22 Mar 2016 10:28:01 +0100 Subject: [PATCH] dev: also count with suffixes in UUID for LVs when constructing VGID and LVID index UUID for LV is either "LVM-" or "LVM--". The code before just checked the length of the UUID based on the first template, not the variant with suffix - so LVs with this suffix were not processed properly. For example a thin pool LV (as an example of an LV that contains sub LVs where UUIDs have suffixes): [0] fedora/~ # lsblk -s /dev/vg/lvol1 NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT vg-lvol1 253:8 0 4M 0 lvm `-vg-pool-tpool 253:6 0 116M 0 lvm |-vg-pool_tmeta 253:2 0 4M 0 lvm | `-sda 8:0 0 128M 0 disk `-vg-pool_tdata 253:3 0 116M 0 lvm `-sda 8:0 0 128M 0 disk Before this patch (spurious warning message about device mismatch): [0] fedora/~ # pvs WARNING: Device mismatch detected for vg/lvol1 which is accessing /dev/mapper/vg-pool-tpool instead of (null). PV VG Fmt Attr PSize PFree /dev/sda vg lvm2 a-- 124.00m 0 With this patch applied (no spurious warning message about device mismatch): [0] fedora/~ # pvs PV VG Fmt Attr PSize PFree /dev/sda vg lvm2 a-- 124.00m 0 --- lib/device/dev-cache.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/lib/device/dev-cache.c b/lib/device/dev-cache.c index bcee783a5..06438d9f7 100644 --- a/lib/device/dev-cache.c +++ b/lib/device/dev-cache.c @@ -453,13 +453,23 @@ static struct device *_get_device_for_sysfs_dev_name_using_devno(const char *dev static int _get_vgid_and_lvid_for_dev(struct device *dev) { - size_t lvm_prefix_len = strlen(UUID_PREFIX); + static size_t lvm_prefix_len = sizeof(UUID_PREFIX) - 1; + static size_t lvm_uuid_len = sizeof(UUID_PREFIX) - 1 + 2 * ID_LEN; char uuid[DM_UUID_LEN]; + size_t uuid_len; if (!_get_dm_uuid_from_sysfs(uuid, sizeof(uuid), (int) MAJOR(dev->dev), (int) MINOR(dev->dev))) return_0; - if (strlen(uuid) == (2 * ID_LEN + 4) && + uuid_len = strlen(uuid); + + /* + * UUID for LV is either "LVM-" or "LVM--", + * where vg_uuid and lv_uuid has length of ID_LEN and suffix len is not restricted + * (only restricted by whole DM UUID max len). + */ + if (((uuid_len == lvm_uuid_len) || + ((uuid_len > lvm_uuid_len) && (uuid[lvm_uuid_len] == '-'))) && !strncmp(uuid, UUID_PREFIX, lvm_prefix_len)) { /* Separate VGID and LVID part from DM UUID. */ if (!(dev->vgid = dm_pool_strndup(_cache.mem, uuid + lvm_prefix_len, ID_LEN)) ||