tree 222449c884848e6ede2fb43e7d0343372aa91192
parent 8e519795041e3293ab6b4e67f5416fa80dc0efc4
author Eric Blake <eblake@redhat.com> 1588105739 -0500
committer Kevin Wolf <kwolf@redhat.com> 1588937195 +0200

nfs: Support BDRV_REQ_ZERO_WRITE for truncate

Our .bdrv_has_zero_init_truncate returns 1 if we detect that the OS
always 0-fills; we can use that same knowledge to implement
BDRV_REQ_ZERO_WRITE by ignoring it when the OS gives it to us for
free.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200428202905.770727-4-eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>