Whether a write cache is used or not is a decision that concerns the
user (e.g. the guest device) rather than the backend. It was already
logically part of the BB level as bdrv_move_feature_fields() always kept
it on top of the BDS tree; with this patch, the core of it (the actual
flag and the additional flushes) is also implemented there.

Direct callers of bdrv_open() must pass BDRV_O_CACHE_WB now if bs
doesn't have a BlockBackend attached.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

The iSCSI driver currently accepts the CHAP password in plain text
as a block driver property. This change adds a new "password-secret"
property that accepts the ID of a QCryptoSecret instance.

  $QEMU \
     -object secret,id=sec0,filename=/home/berrange/example.pw \
     -drive driver=iscsi,url=iscsi://example.com/target-foo/lun1,\
            user=dan,password-secret=sec0
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Message-id: 1453385961-10718-4-git-send-email-berrange@redhat.com
Signed-off-by: NJeff Cody <jcody@redhat.com>

Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-id: 1453780743-16806-6-git-send-email-famz@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

The added parameter can be used to return the BDS pointer which the
valid offset is referring to. Its value should be ignored unless
BDRV_BLOCK_OFFSET_VALID in ret is set.

Until block drivers fill in the right value, let's clear it explicitly
right before calling .bdrv_get_block_status.

The "bs->file" condition in bdrv_co_get_block_status is kept now to keep iotest
case 102 passing, and will be fixed once all drivers return the right file
pointer.
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-id: 1453780743-16806-2-git-send-email-famz@redhat.com
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

When play with Dell MD3000 target, for sure it
is a TYPE_DISK, but readcapacity16 would fail.
Then we find that readcapacity10 succeeded. It
looks like the target just support readcapacity10
even through it is a TYPE_DISK or have some
TYPE_ROM characteristics.

This patch can give a chance to send
readcapacity16 when readcapacity10 failed.
This patch is not harmful to original pathes
Signed-off-by: NZhu Lingshan <lszhu@suse.com>
Message-Id: <1451359934-9236-1-git-send-email-lszhu@suse.com>
[Don't fall through on UNIT ATTENTION. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

fix:The error message for readcapacity 16 incorrectly mentioned
a readcapacity 10 failure, fixed the error message.
Signed-off-by: NZhu Lingshan <lszhu@suse.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

Now the callback is not used any more, drop the field along with all
implementations in block drivers, which are iscsi and raw.
Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-id: 1447064214-29930-8-git-send-email-famz@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

iscsi_ioctl emulates SG_GET_VERSION_NUM and SG_GET_SCSI_ID. Now that
bdrv_ioctl() will be emulated with .bdrv_aio_ioctl, replicate the logic
into iscsi_aio_ioctl to make them consistent.
Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-id: 1447064214-29930-5-git-send-email-famz@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Previously we return -EIO blindly when anything goes wrong. Add a helper
function to parse sense fields and try to make the return code more
meaningful.

This also fixes the default werror configuration (enospc) when we're
using qcow2 on an iscsi lun. The old -EIO not being treated as out of
space error failed to trigger vm stop.
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-Id: <1446699609-11376-1-git-send-email-famz@redhat.com>
[libiscsi 1.9 compatibility - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

All callers pass in false, and the real external ones will switch to
true in coming patches.
Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NJeff Cody <jcody@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

It has been reported that at least tgtd returns a block size of 0
for LUN 0. To avoid running into divide by zero later on and protect
against other problematic block sizes validate the block size right
at connection time.

Cc: qemu-stable@nongnu.org
Reported-by: NAndrey Korolyov <andrey@xdel.ru>
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-Id: <1439552016-8557-1-git-send-email-pl@kamp.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

RHEL7 and others are stuck with libiscsi 1.9.0 since there
unfortunately was an ABI breakage after that release.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1435313881-19366-1-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

libiscsi starting with 1.15 will properly support timeout of iscsi
commands. The default will remain no timeout, but this can
be changed via cmdline parameters, e.g.:

qemu -iscsi timeout=30 -drive file=iscsi://...

If a timeout occurs a reconnect is scheduled and the timed out command
will be requeued for processing after a successful reconnect.

The required API call iscsi_set_timeout is present since libiscsi
1.10 which was released in October 2013. However, due to some bugs
in the libiscsi code the use is not recommended before version 1.15.

Please note that this patch bumps the libiscsi requirement to 1.10
to have all function and macros defined. The patch fixes also a
off-by-one error in the NOP timeout calculation which was fixed
while touching these code parts.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-id: 1434455107-19328-1-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

During migration, QEMU uses fsync()/fdatasync() on the open file
descriptor for read-write block devices to flush data just before
stopping the VM.

However, fsync() on a scsi-generic device returns -EINVAL which
causes the migration to fail. This patch skips flushing data in case
of an SG device, since submitting SCSI commands directly via an SG
character device (e.g. /dev/sg0) bypasses the page cache completely,
anyway.

Note that fsync() not only flushes the page cache but also the disk
cache. The scsi-generic device never sends flushes, and for
migration it assumes that the same SCSI device is used by the
destination host, so it does not issue any SCSI SYNCHRONIZE CACHE
(10) command.

Finally, remove the bdrv_is_sg() test from iscsi_co_flush() since
this is now redundant (we flush the underlying protocol at the end
of bdrv_co_flush() which, with this patch, we never reach).
Signed-off-by: NDimitris Aragiorgis <dimara@arrikto.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Message-id: 1435056300-14924-3-git-send-email-dimara@arrikto.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Instead of checking bs->sg use bdrv_is_sg() consistently throughout
the code.
Signed-off-by: NDimitris Aragiorgis <dimara@arrikto.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Message-id: 1435056300-14924-2-git-send-email-dimara@arrikto.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NLuiz Capitulino <lcapitulino@redhat.com>

raw_bsd already has QEMU_BUILD_BUG_ON(BDRV_SECTOR_SIZE != 512), so iscsi
should relax.
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

the allocationmap has only a hint character. The driver always
double checks that blocks marked unallocated in the cache are
still unallocated before taking the fast path and return zeroes.
So using the allocationmap is migration safe and can
also be enabled with cache.direct=on.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-id: 1429193313-4263-10-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-id: 1429193313-4263-9-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

a target may issue a SCSI_STATUS_TASK_SET_FULL status
if there is more than one "BUSY" command queued already.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-id: 1429193313-4263-8-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The idea is that a command is retried in a BUSY condition
up a time of approx. 60 seconds before it is failed. This should
be far higher than any command timeout in the guest.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-id: 1429193313-4263-7-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

SCSI allowes to tell the target to not return from a write command
if the date is not written to the disk. Use this so called FUA
bit if it is supported to optimize WRITE commands if writeback is
not allowed.

In this case qemu always issues a WRITE followed by a FLUSH. This
is 2 round trip times. If we set the FUA bit we can ignore the
following FLUSH.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-id: 1429193313-4263-6-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-id: 1429193313-4263-5-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-id: 1429193313-4263-4-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-id: 1429193313-4263-3-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

We actually were always impolitely dropping the connection and
not cleanly logging out.

CC: qemu-stable@nongnu.org
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-id: 1429193313-4263-2-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

newer libiscsi versions may return zero events from iscsi_which_events.

In this case iscsi_service will return immediately without any progress.
To avoid busy waiting for iscsi_which_events to change we deregister all
read and write handlers in this case and schedule a timer to periodically
check iscsi_which_events for changed events.

Next libiscsi version will introduce async reconnects and zero events
are returned while libiscsi is waiting for a reconnect retry.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-id: 1428437295-29577-1-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

The variable user in struct iscsi_url is a character array, not a pointer.
Therefore its address will never be NULL.

clang reports this error:

block/iscsi.c:1329:20: warning:
 comparison of array 'iscsi_url->user' not equal to a null pointer
 is always true [-Wtautological-pointer-compare]
Reviewed-by: NPeter Lieven <pl@kamp.de>
Acked-by: NPeter Lieven <pl@kamp.de>
Signed-off-by: NStefan Weil <sw@weilnetz.de>
Message-Id: <1425719670-5486-1-git-send-email-sw@weilnetz.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Save the write protected flag and check before reopen.
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-Id: <1424839208-5195-1-git-send-email-famz@redhat.com>
[Fixed typo in the name of the new field. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

'ret' was never initialized in the success path.
Signed-off-by: NPeter Wu <peter@lekensteyn.nl>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Cancel oversized requests early. They would generate
an iSCSI protocol error anyway; after having transferred
possibly a lot of data over the wire.
Suggested-By: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NPeter Lieven <pl@kamp.de>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

As Max pointed out there is a hidden cast from int64_t to int for all
limits. So use the newly introduced sector_limits_lun2qemu for all
limits received from the target.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Copy the max_xfer_len from the BlockLimits VPD or use the
maximum value fitting in the CDB.

The helper function sector_limits_lun2qemu is introduced to convert
and cap the limits from the VPD to the maximum power of two fitting
in an integer; integer is the range for nb_sectors throughout
the block layer.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Before, when a write protected iSCSI target is attached as scsi-disk
with BDRV_O_RDWR, we report it as writable, while in fact all writes
will fail.

One way to improve this is to report write protect flag as true to
guest, but a even better way is to refuse using a write protected LUN to
guest.

Target write protect flag is checked with a mode sense query.
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

I'll use it with block backends shortly, and the name is going to fit
badly there.  It's a block layer thing anyway, not just a block driver
thing.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

I'll use BlockDriverAIOCB with block backends shortly, and the name is
going to fit badly there.  It's a block layer thing anyway, not just a
block driver thing.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Creating an anonymous BDS can't fail.  Make that obvious.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NBenoît Canet <benoit.canet@nodalink.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Signed-off-by: NPeter Lieven <pl@kamp.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

iscsi_aio_write16_cb, iscsi_aio_writev, iscsi_aio_read16_cb, and
iscsi_aio_readv have not not been in use since commit
063c3378 ("block/iscsi: introduce
bdrv_co_{readv, writev, flush_to_disk}").

These were the only trace events in block/iscsi.c so drop the the
trace.h include.

Cc: Peter Lieven <pl@kamp.de>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Message-id: 1411394595-15300-4-git-send-email-stefanha@redhat.com