qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Ronnie Sahlberg <ronniesahlberg@gmail.com>
To: kwolf@redhat.com, qemu-devel@nongnu.org, pbonzini@redhat.com
Subject: [Qemu-devel] [PATCH] Two trivial patches for iSCSI and blank DVDs
Date: Fri, 17 Aug 2012 12:36:19 +1000	[thread overview]
Message-ID: <1345170981-7738-1-git-send-email-ronniesahlberg@gmail.com> (raw)

Kevin, List, Paolo

Please find two trivial patches to the iscsi block driver.

1, If the LUN contains a blank disk then the readcapacity10 data will
contain a ReturnedLogicalBlockAddress of 0. For this case this does not mean that the device contains one readable block and can be read from.
This is a special case for a blank disk that contains no readable blocks at all. This change makes bdrv_getlength()/iscsi_getlength() now rerurn a size of 0  for iSCSI LUNs that contain a blank disk.

2, If the iSCSI LUN contains a blank disk then we can not read or write to it using bdrv_*() functions since there is no bdrv api for writeable mmc devices.
For this case with a blank disk force the use of scsi-generic just like 
we do for tape and mediachanger devices.
This allows the guest to talk directly to the target LUN and write to/burn the disk.


I have confirmed that 

  dvdrecord -dao -ignsize -overburn dev=/dev/sg1 <some-file>.iso

works from a qemu guest to burn an iSCSI cdrom with these patches.

regards
ronnie sahlberg

             reply	other threads:[~2012-08-17  2:36 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-08-17  2:36 Ronnie Sahlberg [this message]
2012-08-17  2:36 ` [Qemu-devel] [PATCH 1/2] ISCSI: Set number of blocks to 0 for blank CDROM devices Ronnie Sahlberg
2012-08-18 21:57   ` Paolo Bonzini
2012-08-18 22:06     ` ronnie sahlberg
2012-08-17  2:36 ` [Qemu-devel] [PATCH 2/2] ISCSI: Force scsi-generic for MMC with blank disks Ronnie Sahlberg
2012-08-18 14:23   ` Blue Swirl
2012-08-18 21:58   ` Paolo Bonzini
2012-08-18 22:02     ` ronnie sahlberg
2012-08-18 22:04       ` ronnie sahlberg
2012-08-18 22:16       ` Paolo Bonzini
2012-08-18 22:19         ` ronnie sahlberg
2012-08-18 22:41           ` Paolo Bonzini
2012-08-18 22:20       ` Paolo Bonzini
2012-08-18 23:44         ` ronnie sahlberg
2012-08-19 10:16           ` Paolo Bonzini

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1345170981-7738-1-git-send-email-ronniesahlberg@gmail.com \
    --to=ronniesahlberg@gmail.com \
    --cc=kwolf@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=qemu-devel@nongnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).