Add Loop Device package
This adds Loop device support in our Linux kernel and adds a Go package for working with them.
It also drive-by adds a pre-mounted tmpfs to ktest as that is quite useful in a lot of situations.
Test Plan: Comes with ktests.
X-Origin-Diff: phab/D745
GitOrigin-RevId: fa06bcdddc033efb136f56da3b4a91159273bf88
diff --git a/third_party/linux/linux-metropolis.config b/third_party/linux/linux-metropolis.config
index f03e66b..acb41b5 100644
--- a/third_party/linux/linux-metropolis.config
+++ b/third_party/linux/linux-metropolis.config
@@ -1283,7 +1283,9 @@
# CONFIG_BLK_DEV_FD is not set
# CONFIG_BLK_DEV_PCIESSD_MTIP32XX is not set
# CONFIG_BLK_DEV_UMEM is not set
-# CONFIG_BLK_DEV_LOOP is not set
+CONFIG_BLK_DEV_LOOP=y
+CONFIG_BLK_DEV_LOOP_MIN_COUNT=0
+# CONFIG_BLK_DEV_CRYPTOLOOP is not set
# CONFIG_BLK_DEV_DRBD is not set
# CONFIG_BLK_DEV_NBD is not set
# CONFIG_BLK_DEV_SKD is not set