On 10/17/24 18:09, Keith Busch wrote:
From: Kanchan Joshi <joshi.k@xxxxxxxxxxx> With F_SET_RW_HINT fcntl, user can set a hint on the file inode, and all the subsequent writes on the file pass that hint value down. This can be limiting for block device as all the writes can be tagged with only one lifetime hint value. Concurrent writes (with different hint values) are hard to manage. Per-IO hinting solves that problem. Allow userspace to pass additional metadata in the SQE. __u16 write_hint; This accepts all hint values that the file allows. The write handlers (io_prep_rw, io_write) send the hint value to lower-layer using kiocb. This is good for upporting direct IO, but not when kiocb is not available (e.g., buffered IO). When per-io hints are not passed, the per-inode hint values are set in the kiocb (as before). Otherwise, per-io hints take the precedence over per-inode hints. Signed-off-by: Kanchan Joshi <joshi.k@xxxxxxxxxxx> Signed-off-by: Nitesh Shetty <nj.shetty@xxxxxxxxxxx> Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx> --- include/uapi/linux/io_uring.h | 4 ++++ io_uring/rw.c | 11 +++++++++-- 2 files changed, 13 insertions(+), 2 deletions(-)
Reviewed-by: Hannes Reinecke <hare@xxxxxxx> Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@xxxxxxx +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich
