From: Adam Kupczyk <akupczyk@ibm.com>
Date: Thu, 25 Sep 2025 07:03:12 +0000 (-0400)
Subject: extblkdev/fcm: Refuse to operate on multimedia lvm block devices
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=4f85256062af71bc33554ed5664bb4d6bfd5dfa7;p=ceph.git

extblkdev/fcm: Refuse to operate on multimedia lvm block devices

BlueStore is selecting were data is put to the device.
Merging 2 FCM devices together means that BlueStore will see free space
on one of the devices, but not know the other is full and asking to put
data there. It will cause -ENOSPC while free space is reported.

Signed-off-by: Adam Kupczyk <akupczyk@ibm.com>
---

diff --git a/src/extblkdev/fcm/ExtBlkDevPluginFcm.cc b/src/extblkdev/fcm/ExtBlkDevPluginFcm.cc
index 957c056f2884..06ef9ecefb89 100644
--- a/src/extblkdev/fcm/ExtBlkDevPluginFcm.cc
+++ b/src/extblkdev/fcm/ExtBlkDevPluginFcm.cc
@@ -296,6 +296,9 @@ public:
     // determine device name for underlying hardware
     std::set<std::string> raw_devices;
     get_raw_devices(logdevname, &raw_devices);
+    if (raw_devices.size() > 1) {
+      ceph_abort("Device " + logdevname_a + " consist of "+ raw_devices.size() + " devices: " + raw_devices);
+    }
     for (auto& d : raw_devices) {
       std::string devpath = "/sys/block/" + d + "/device/";
       uint32_t vendor;