On 05/04/2016 14:07, Alex Bligh wrote: > Improve the documentation of NBD_CMD_FLUSH and NBD_CMD_FLAG_FUA. Specifically > the latter may be set on any command, and its semantics on commands other > than NBD_CMD_WRITE need explaining. Further, explain how these relate to > reordering of commands. > > Signed-off-by: Alex Bligh <alex-rWA27mgs/[email protected]> > --- > doc/proto.md | 51 +++++++++++++++++++++++++++++++++++++++++---------- > 1 file changed, 41 insertions(+), 10 deletions(-) > > ARRRGH - this time with a proper commit header. > > Changes since version 2: > > * Rebase on master > > * Remove bogus 'SHOULD' for FLUSH in relation to writes that are in flight > but not yet completed > > * After consultation with lkml etc., document that FUA on things that do not > write does nothing > > * Document that sending FUA for commands that do nothing is permissible, but > 'SHOULD NOT' be done; an existing client does this.
Can you send a pointer to the discussion? FUA on reads definitely does *something* in SCSI (it ensures that the data is moved out of the volatile cache prior to the read, similar to what QEMU implements). Paolo > * Document that FUA on TRIM should do something after all, per Kevin Wolf's > comment ------------------------------------------------------------------------------ _______________________________________________ Nbd-general mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/nbd-general
