stat_to_qid attempts via qid_path_prefixmap to map unique files (which are
identified by 64 bit inode nr and 32 bit device id) to a 64 QID path value.
However this implementation makes some assumptions about inode number
generation on the host.
If qid_path_prefixmap fails, we still have 48 bits available in the QID
path to fall back to a less memory efficient full mapping.
Signed-off-by: Antonios Motakis <antonios.motakis@huawei.com>
[CS: - Rebased to https://github.com/gkurz/qemu/commits/9p-next
(SHA1 7fc4c49e91).
- Updated hash calls to new xxhash API.
- Removed unnecessary parantheses in qpf_lookup_func().
- Removed unnecessary g_malloc0() result checks.
- Log error message when running out of prefixes in
qid_path_fullmap().
- Log warning message about potential degraded performance in
qid_path_prefixmap().
- Wrapped qpf_table initialization to dedicated qpf_table_init()
function.
- Fixed typo in comment. ]
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
f3fe4a2d92