OpenZFS 6738 - zfs send stream padding needs documentation

Authored by: Eli Rosenthal <eli.rosenthal@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>

OpenZFS-issue: https://www.illumos.org/issues/6738
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/c20404ff
This commit is contained in:
Eli Rosenthal 2016-06-09 12:07:01 -07:00 committed by Brian Behlendorf
parent b607405fea
commit f8866f8ae3

View File

@ -107,6 +107,19 @@ dump_bytes_cb(void *arg)
dmu_sendarg_t *dsp = dbi->dbi_dsp;
dsl_dataset_t *ds = dmu_objset_ds(dsp->dsa_os);
ssize_t resid; /* have to get resid to get detailed errno */
/*
* The code does not rely on this (len being a multiple of 8). We keep
* this assertion because of the corresponding assertion in
* receive_read(). Keeping this assertion ensures that we do not
* inadvertently break backwards compatibility (causing the assertion
* in receive_read() to trigger on old software).
*
* Removing the assertions could be rolled into a new feature that uses
* data that isn't 8-byte aligned; if the assertions were removed, a
* feature flag would have to be added.
*/
ASSERT0(dbi->dbi_len % 8);
dsp->dsa_err = vn_rdwr(UIO_WRITE, dsp->dsa_vp,
@ -1806,7 +1819,10 @@ receive_read(struct receive_arg *ra, int len, void *buf)
{
int done = 0;
/* some things will require 8-byte alignment, so everything must */
/*
* The code doesn't rely on this (lengths being multiples of 8). See
* comment in dump_bytes.
*/
ASSERT0(len % 8);
while (done < len) {