diff options
| author | Ronnie Sahlberg <ronniesahlberg@gmail.com> | 2012-05-26 14:56:41 +1000 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2012-07-02 10:18:41 +0200 |
| commit | 622695a4585a786fdcd53852c7af87ed0af1af80 (patch) | |
| tree | 966a2bbdc0d9083ee704961e4ee9212e8c1f3fbe /block | |
| parent | 983924532f61091fd90d1f2fafa4aa938c414dbb (diff) | |
ISCSI: force use of sg for SMC and SSC devices
If the device we open is a SMC or SSC device, then force the use of sg. We
dont have any medium changer or tape emulation so only passthrough via
real sg or scsi-generic via iscsi would work anyway.
Forcing sg also makes qemu skip trying to read from the device to guess
the image format by reading from the device (find_image_format()).
SMC devices do not implement READ6/10/12/16 so it is not possible to
read from them (SSC have different CDBs).
With this patch I can successfully manage a SMC device wiht iscsi in
passthrough mode.
Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
[Added TYPE_TAPE handling - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/iscsi.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/block/iscsi.c b/block/iscsi.c index 029739eb61..ac65277048 100644 --- a/block/iscsi.c +++ b/block/iscsi.c @@ -1022,6 +1022,16 @@ static int iscsi_open(BlockDriverState *bs, const char *filename, int flags) if (iscsi_url != NULL) { iscsi_destroy_url(iscsi_url); } + + /* Medium changer or tape. We dont have any emulation for this so this must + * be sg ioctl compatible. We force it to be sg, otherwise qemu will try + * to read from the device to guess the image format. + */ + if (iscsilun->type == TYPE_MEDIUM_CHANGER || + iscsilun->type == TYPE_TAPE) { + bs->sg = 1; + } + return 0; failed: |