motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-05 00:33:55 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

nfs: Support BDRV_REQ_ZERO_WRITE for truncate

Browse source 
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>
This commit is contained in:
Eric Blake 2020-04-28 15:28:59 -05:00 • committed by Kevin Wolf
parent 8e51979504
commit 8f23aaf5d6
1 changed files with 3 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

3
block/nfs.c
View file

@ -620,6 +620,9 @@ static int nfs_file_open(BlockDriverState *bs, QDict *options, int flags,
}
bs->total_sectors = ret;
if (client->has_zero_init) {
bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE;
}
return 0;
}