This patch introduces idmapped mounts support for
container rootfs.
The idmapped mounts support was merged in Linux kernel 5.12
torvalds/linux@7d6beb7.
This functionality allows to address chown overhead for containers that
use user namespace.
The changes are based on experimental patchset published by
Mauricio Vásquez #4734.
Current version reiplements support of idmapped mounts using Golang.
Performance measurement results:
Image idmapped mount recursive chown
BusyBox 00.135 04.964
Ubuntu 00.171 15.713
Fedora 00.143 38.799
Signed-off-by: Mauricio Vásquez <mauricio@kinvolk.io>
Signed-off-by: Artem Kuzin <artem.kuzin@huawei.com>
Signed-off-by: Alexey Perevalov <alexey.perevalov@huawei.com>
Signed-off-by: Ilya Hanov <ilya.hanov@huawei-partners.com>
1555a31bf6