From 624f3006b8a26bcf7a0b2be13265ac99c65fd117 Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Wed, 14 Feb 2018 21:49:15 +0100 Subject: block/ssh: Add basic .bdrv_truncate() libssh2 does not seem to offer real truncation support, so we can only grow files -- but that is better than nothing. Signed-off-by: Max Reitz Message-id: 20180214204915.7980-4-mreitz@redhat.com Reviewed-by: Eric Blake Reviewed-by: Richard W.M. Jones Signed-off-by: Max Reitz --- block/ssh.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'block/ssh.c') diff --git a/block/ssh.c b/block/ssh.c index 4bcf10334f..80a8b40dfa 100644 --- a/block/ssh.c +++ b/block/ssh.c @@ -1220,6 +1220,29 @@ static int64_t ssh_getlength(BlockDriverState *bs) return length; } +static int ssh_truncate(BlockDriverState *bs, int64_t offset, + PreallocMode prealloc, Error **errp) +{ + BDRVSSHState *s = bs->opaque; + + if (prealloc != PREALLOC_MODE_OFF) { + error_setg(errp, "Unsupported preallocation mode '%s'", + PreallocMode_str(prealloc)); + return -ENOTSUP; + } + + if (offset < s->attrs.filesize) { + error_setg(errp, "ssh driver does not support shrinking files"); + return -ENOTSUP; + } + + if (offset == s->attrs.filesize) { + return 0; + } + + return ssh_grow_file(s, offset, errp); +} + static BlockDriver bdrv_ssh = { .format_name = "ssh", .protocol_name = "ssh", @@ -1232,6 +1255,7 @@ static BlockDriver bdrv_ssh = { .bdrv_co_readv = ssh_co_readv, .bdrv_co_writev = ssh_co_writev, .bdrv_getlength = ssh_getlength, + .bdrv_truncate = ssh_truncate, .bdrv_co_flush_to_disk = ssh_co_flush, .create_opts = &ssh_create_opts, }; -- cgit v1.2.3