Hello Michael, Tuesday, January 23, 2018, 1:20:28 AM, you wrote: > On 01/22/2018 01:59 PM, Stefan Priebe - Profihost AG wrote: >> Hello, >> >> what's the best way to get the correct bcache backing device (bdev) form >> a known dev (f.e. /dev/bcache2)? >> >> I haven't found an easy reliable way through /sys/block. >> >> Thanks! >> >> Greets, >> Stefan > /sys/block/bcache0/slaves This lists both the backing device and the cache device(s), without an (apparent) way of identifying which one is backing. > /sys/block/bcache0/bcache/cache/bdev0 /sys/block/bcache0/bcache/cache links to the cache set (/sys/fs/bcache/[UUID]) which can serve several bcache devices, so bdev0 would link to the first backing device registered in the set, not the backing device that corresponds to the bcache device we started with. However, it's actually possible to go further: iterate all bdevX devices and identify the correct one by looking at the "dev" symlink: /sys/block/bcache0/bcache/cache/bdev0/dev /sys/block/bcache0/bcache/cache/bdev1/dev etc. The device whose "dev" symlink points to bcache0 should be the backing device for bcache0. Pavel Goran -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
