Re: [Qemu-block] [PATCH] qcow2: do lazy allocation of the L2 cache

On Fri 24 Apr 2015 03:04:06 PM CEST, Kevin Wolf kw...@redhat.com wrote: I think it would be nice to have a way to free unused cache entries after a while. Do you think mmap plus a periodic timer would work? I'm hesitant about changes like this because they make QEMU more complex,

[Qemu-block] [PATCH COLO v4 09/15] Introduce a new -drive option to control whether to connect to remote target

Signed-off-by: Wen Congyang we...@cn.fujitsu.com Signed-off-by: zhanghailiang zhang.zhanghaili...@huawei.com Signed-off-by: Gonglei arei.gong...@huawei.com --- blockdev.c| 8 include/block/block.h | 1 + qemu-options.hx | 4 3 files changed, 13 insertions(+) diff

Re: [Qemu-block] [RFC PATCH 0/7] Fix transactional snapshot with virtio-blk dataplane

On Thu, May 07, 2015 at 02:43:43PM +0100, Stefan Hajnoczi wrote: On Wed, May 06, 2015 at 07:23:32PM +0800, Fam Zheng wrote: Reported by Paolo. Unlike the iohandler in main loop, iothreads currently process the event notifier used as virtio-blk ioeventfd in all nested aio_poll. This is

[Qemu-block] [PATCH COLO v4 05/15] Backup: clear all bitmap when doing block checkpoint

Signed-off-by: Wen Congyang we...@cn.fujitsu.com Signed-off-by: zhanghailiang zhang.zhanghaili...@huawei.com Signed-off-by: Gonglei arei.gong...@huawei.com Cc: Jeff Cody jc...@redhat.com --- block/backup.c | 13 + blockjob.c | 10 ++

[Qemu-block] [PATCH COLO v4 04/15] block: Parse backing_reference option to reference existing BDS

Usage: -drive file=xxx,id=Y, \ -drive file=,id=X,backing_reference.drive_id=Y,backing_reference.hidden-disk.* It will create such backing chain: {virtio-blk dev 'Y'} {virtio-blk dev 'X'} |

[Qemu-block] [PATCH COLO v4 01/15] docs: block replication's description

Signed-off-by: Wen Congyang we...@cn.fujitsu.com Signed-off-by: Yang Hongyang yan...@cn.fujitsu.com Signed-off-by: zhanghailiang zhang.zhanghaili...@huawei.com Signed-off-by: Gonglei arei.gong...@huawei.com --- docs/block-replication.txt | 179 + 1 file

[Qemu-block] [PATCH COLO v4 14/15] quorum: allow ignoring child errors

If the child is not ready, read/write/getlength/flush will return -errno. It is not critical error, and can be ignored: 1. read/write: Just not report the error event. 2. getlength: just ignore it. If all children's getlength return -errno, and be ignored, return -EIO. 3. flush: Just

[Qemu-block] [PATCH COLO v4 13/15] quorum: implement block driver interfaces for block replication

Signed-off-by: Wen Congyang we...@cn.fujitsu.com Signed-off-by: zhanghailiang zhang.zhanghaili...@huawei.com Signed-off-by: Gonglei arei.gong...@huawei.com --- block/quorum.c | 78 ++ 1 file changed, 78 insertions(+) diff --git

[Qemu-block] [PATCH COLO v4 06/15] Don't allow a disk use backing reference target

Signed-off-by: Wen Congyang we...@cn.fujitsu.com Signed-off-by: zhanghailiang zhang.zhanghaili...@huawei.com Signed-off-by: Gonglei arei.gong...@huawei.com --- block.c | 9 + 1 file changed, 9 insertions(+) diff --git a/block.c b/block.c index 35e1a95..15d21da 100644 --- a/block.c +++

[Qemu-block] [PATCH COLO v4 03/15] Allow creating backup jobs when opening BDS

When opening BDS, we need to create backup jobs for image-fleecing. Signed-off-by: Wen Congyang we...@cn.fujitsu.com Signed-off-by: zhanghailiang zhang.zhanghaili...@huawei.com Signed-off-by: Gonglei arei.gong...@huawei.com Cc: Jeff Cody jc...@redhat.com --- block/Makefile.objs | 2 +- 1 file

Re: [Qemu-block] [PATCH COLO v3 01/14] docs: block replication's description

On Tue, May 05, 2015 at 04:23:56PM +0100, Dr. David Alan Gilbert wrote: * Stefan Hajnoczi (stefa...@redhat.com) wrote: On Fri, Apr 24, 2015 at 11:36:35AM +0200, Paolo Bonzini wrote: On 24/04/2015 11:38, Wen Congyang wrote: That can be done with drive-mirror. But I think

[Qemu-block] [PATCH COLO v4 12/15] skip nbd_target when starting block replication

Signed-off-by: Wen Congyang we...@cn.fujitsu.com Signed-off-by: zhanghailiang zhang.zhanghaili...@huawei.com Signed-off-by: Gonglei arei.gong...@huawei.com --- block.c | 12 1 file changed, 12 insertions(+) diff --git a/block.c b/block.c index 54d5b29..a442b5f 100644 --- a/block.c

[Qemu-block] [PATCH COLO v4 15/15] Implement new driver for block replication

Signed-off-by: Wen Congyang we...@cn.fujitsu.com Signed-off-by: zhanghailiang zhang.zhanghaili...@huawei.com Signed-off-by: Gonglei arei.gong...@huawei.com --- block/Makefile.objs | 1 + block/replication.c | 512 2 files changed, 513

Re: [Qemu-block] [PATCH] qcow2: Flush pending discards before allocating cluster

Am 06.05.2015 um 13:29 hat Kevin Wolf geschrieben: Before a freed cluster can be reused, pending discards for this cluster must be processed. The original assumption was that this was not a problem because discards are only cached during discard/write zeroes operations, which are

Re: [Qemu-block] [PATCH COLO v3 01/14] docs: block replication's description

* Stefan Hajnoczi (stefa...@redhat.com) wrote: On Tue, May 05, 2015 at 04:23:56PM +0100, Dr. David Alan Gilbert wrote: * Stefan Hajnoczi (stefa...@redhat.com) wrote: On Fri, Apr 24, 2015 at 11:36:35AM +0200, Paolo Bonzini wrote: On 24/04/2015 11:38, Wen Congyang wrote:

Re: [Qemu-block] [PATCH] qcow2: do lazy allocation of the L2 cache

Am 08.05.2015 um 11:00 hat Alberto Garcia geschrieben: On Fri 24 Apr 2015 03:04:06 PM CEST, Kevin Wolf kw...@redhat.com wrote: I think it would be nice to have a way to free unused cache entries after a while. Do you think mmap plus a periodic timer would work? I'm hesitant

Re: [Qemu-block] [PATCH] vmdk: Fix next_cluster_sector for compressed write

Am 06.05.2015 um 20:01 hat Max Reitz geschrieben: On 06.05.2015 14:23, Fam Zheng wrote: This fixes the bug introduced by commit c6ac36e (vmdk: Optimize cluster allocation). Sometimes, write_len could be larger than cluster size, because it contains both data and marker. We must advance

Re: [Qemu-block] [Qemu-devel] [PATCH v2 0/3] block: Warn about usage of growing formats over non-growable protocols

On 08/05/2015 12:34, Kevin Wolf wrote: Am 08.05.2015 um 12:16 hat Paolo Bonzini geschrieben: On 08/05/2015 12:08, Kevin Wolf wrote: If so, the commands seem to be hopelessly underspecified, especially with respect to error conditions. And where it says something about errors, it doesn't

Re: [Qemu-block] [Qemu-devel] [PATCH v3 01/10] qapi: Add transaction support to block-dirty-bitmap operations

On 08.05.2015 15:14, Stefan Hajnoczi wrote: On Thu, May 07, 2015 at 01:22:26PM -0400, John Snow wrote: On 05/07/2015 10:54 AM, Stefan Hajnoczi wrote: On Wed, Apr 22, 2015 at 08:04:44PM -0400, John Snow wrote: +static void block_dirty_bitmap_clear_prepare(BlkTransactionState *common, +

Re: [Qemu-block] [PATCH 1/7] qcow2: use one single memory block for the L2/refcount cache tables

On 06.05.2015 15:39, Alberto Garcia wrote: The qcow2 L2/refcount cache contains one separate table for each cache entry. Doing one allocation per table adds unnecessary overhead and it also requires us to store the address of each table separately. Since the size of the cache is constant during

Re: [Qemu-block] [PATCH 4/7] qcow2: remove qcow2_cache_find_entry_to_replace()

On 06.05.2015 15:39, Alberto Garcia wrote: A cache miss means that the whole array was traversed and the entry we were looking for was not found, so there's no need to traverse it again in order to select an entry to replace. Signed-off-by: Alberto Garcia be...@igalia.com ---

Re: [Qemu-block] [PATCH 3/7] qcow2: use an LRU algorithm to replace entries from the L2 cache

On 06.05.2015 15:39, Alberto Garcia wrote: The current algorithm to evict entries from the cache gives always preference to those in the lowest positions. As the size of the cache increases, the chances of the later elements of being removed decrease exponentially. In a scenario with random I/O

Re: [Qemu-block] [PATCH 5/7] qcow2: use a hash to look for entries in the L2 cache

On 06.05.2015 15:39, Alberto Garcia wrote: The current cache algorithm traverses the array starting always from the beginning, so the average number of comparisons needed to perform a lookup is proportional to the size of the array. By using a hash of the offset as the starting point, lookups

[Qemu-block] [PATCH 25/34] block: Allow specifying child options in reopen

If the child was defined in the same context (-drive argument or blockdev-add QMP command) as its parent, a reopen of the parent should work the same and allow changing options of the child. Signed-off-by: Kevin Wolf kw...@redhat.com --- block.c | 12 ++-- 1 file changed, 10

[Qemu-block] [PATCH 33/34] qemu-iotests: Test cache mode option inheritance

This is doing a more complete test on setting cache modes both while opening an image (i.e. in a -drive command line) and in reopen situations. It checks that reopen can specify options for child nodes and that cache modes are correctly inherited from parent nodes where they are not specified.

[Qemu-block] [PATCH 09/34] block: Add BlockDriverState.inherits_from

Currently, the block layer assumes that any block node can have only one parent, and if it has a parent, that it inherits some options/flags from this parent. This is not true any more: With references used in block device creation, a single node can be used by multiple parents, or it can be

[Qemu-block] [PATCH 31/34] block: Move cache options into options QDict

This adds the cache mode options to the QDict, so that they can be specified for child nodes (e.g. backing.cache.direct=off). The cache modes are not removed from the flags at this point; instead, options and flags are kept in sync. If the user specifies both flags and options, the options take

[Qemu-block] [PATCH 12/34] block: Allow specifying driver-specific options to reopen

Signed-off-by: Kevin Wolf kw...@redhat.com --- block.c | 42 +++--- block/commit.c| 4 ++-- include/block/block.h | 4 +++- 3 files changed, 44 insertions(+), 6 deletions(-) diff --git a/block.c b/block.c index 95dc51e..561cefd 100644

[Qemu-block] [PATCH 00/34] block: Cache mode for children, reopen overhaul and more

First of all, sorry for the lengthy series that attacks more things than could fit in the subject line. However, for the most part the changes are hard to separate: Either it's just infrastructure without a user, or it's a user, but the infrastructure changes wouldn't be complete. The only

[Qemu-block] [PATCH 01/34] qdict: Add qdict_array_entries()

Signed-off-by: Kevin Wolf kw...@redhat.com --- include/qapi/qmp/qdict.h | 1 + qobject/qdict.c | 68 +--- 2 files changed, 65 insertions(+), 4 deletions(-) diff --git a/include/qapi/qmp/qdict.h b/include/qapi/qmp/qdict.h index

[Qemu-block] [PATCH 02/34] qdict: Add qdict_{set,copy}_default()

In the block layer functions that determine options for a child block device, it's a common pattern to either copy options from the parent's options or to set a default string if the option isn't explicitly set yet for the child. Provide convenience functions so that it becomes a one-liner for

Re: [Qemu-block] [PATCH 5/7] qcow2: use a hash to look for entries in the L2 cache

On Fri 08 May 2015 05:46:57 PM CEST, Max Reitz wrote: Let's assume the cache is full. Now this hash algorithm (direct mapped cache) basically becomes futile, because the LRU algorithm (fully associative cache) takes over That's right, although in that scenario I guess there's no good

Re: [Qemu-block] [PATCH 6/7] qcow2: make qcow2_cache_put() a void function

On 06.05.2015 15:39, Alberto Garcia wrote: This function never receives an invalid table pointer, so we can make it void and remove all the error checking code. Signed-off-by: Alberto Garcia be...@igalia.com --- block/qcow2-cache.c| 7 +-- block/qcow2-cluster.c | 50

[Qemu-block] [PATCH 21/34] block: Consider all block layer options in append_open_options

The code already special-cased node-name, which is currently the only option passed in the QDict that isn't driver-specific. Generalise the code to take all general block layer options into consideration. Signed-off-by: Kevin Wolf kw...@redhat.com --- block.c | 26 ++ 1

[Qemu-block] [PATCH 18/34] qcow2: Fix memory leak in qcow2_update_options() error path

Signed-off-by: Kevin Wolf kw...@redhat.com --- block/qcow2.c | 12 ++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/block/qcow2.c b/block/qcow2.c index abe22f3..84d6e0f 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -546,8 +546,8 @@ static int

[Qemu-block] [PATCH 20/34] qcow2: Support updating driver-specific options in reopen

For updating the cache sizes or disabling lazy refcounts there is a bit more to do than just changing the variables, but otherwise we're all set for changing options during bdrv_reopen(). Just implement the missing pieces and hook the functions up in bdrv_reopen(). Signed-off-by: Kevin Wolf

[Qemu-block] [PATCH 19/34] qcow2: Make qcow2_update_options() suitable for transactions

Before we can allow updating options at runtime with bdrv_reopen(), we need to split the function into prepare/commit/abort parts. Signed-off-by: Kevin Wolf kw...@redhat.com --- block/qcow2.c | 101 ++ 1 file changed, 67 insertions(+), 34

[Qemu-block] [PATCH 27/34] block: Add infrastructure for option inheritance

Options are not actually inherited from the parent node yet, but this commit lays the grounds for doing so. Signed-off-by: Kevin Wolf kw...@redhat.com --- block.c | 51 ++- include/block/block_int.h | 3 ++- 2 files changed, 30

Re: [Qemu-block] [PATCH 6/7] qcow2: make qcow2_cache_put() a void function

On Fri 08 May 2015 05:51:30 PM CEST, Max Reitz wrote: -int qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table) +void qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table) { int i = qcow2_cache_get_table_idx(bs, c, *table); -if (c-entries[i].offset

Re: [Qemu-block] [Qemu-devel] [PATCH v3 01/10] qapi: Add transaction support to block-dirty-bitmap operations

On 05/08/2015 09:17 AM, Max Reitz wrote: On 08.05.2015 15:14, Stefan Hajnoczi wrote: On Thu, May 07, 2015 at 01:22:26PM -0400, John Snow wrote: On 05/07/2015 10:54 AM, Stefan Hajnoczi wrote: On Wed, Apr 22, 2015 at 08:04:44PM -0400, John Snow wrote: +static void

[Qemu-block] [PATCH 23/34] block: Pass driver-specific options to .bdrv_refresh_filename()

In order to decide whether a blkdebug: filename can be produced or a json: one is necessary, blkdebug checked whether bs-options had more options than just config, x-image or image (the latter including nested options). That doesn't work well when generic block layer options are present. This

[Qemu-block] [PATCH 29/34] qemu-iotests: Remove cache mode test without medium

Specifying the cache mode for a driver without a medium is not a useful thing to do: As long as there is no medium, the cache mode doesn't make a difference, and once the 'change' command is used to insert a medium, it ignores the old cache mode and makes the new medium use cache=writethrough.

[Qemu-block] [PATCH 13/34] qemu-io: Add command 'reopen'

Signed-off-by: Kevin Wolf kw...@redhat.com --- qemu-io-cmds.c | 71 ++ 1 file changed, 71 insertions(+) diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c index 1afcfc0..ef8f3fd 100644 --- a/qemu-io-cmds.c +++ b/qemu-io-cmds.c @@ -1978,6 +1978,76

[Qemu-block] [PATCH 24/34] block: Keep driver in bs-options

Instead of passing a separate drv argument to bdrv_open_common(), just make sure that a driver option is set in the QDict. This also means that a driver entry is consistently present in bs-options now. This is another step towards keeping all options in the QDict (which is the represenation of

[Qemu-block] [PATCH 22/34] block: Exclude nested options only for children in append_open_options()

Some drivers have nested options (e.g. blkdebug rule arrays), which don't belong to a child node and shouldn't be removed. Don't remove all options with . in their name, but check for the complete prefixes of actually existing child nodes. Signed-off-by: Kevin Wolf kw...@redhat.com --- block.c

[Qemu-block] [PATCH v2 5/5] raw-posix: Introduce hdev_is_sg()

Until now, an SG device was identified only by checking if its path started with /dev/sg. Then, hdev_open() set bs-sg accordingly. This is very fragile, e.g. it fails with symlinks or relative paths. We should rely on the actual properties of the device instead of the specified file path. Test

[Qemu-block] [PATCH v2 1/5] block: Use bdrv_is_sg() everywhere

Instead of checking bs-sg use bdrv_is_sg() consistently throughout the code. Signed-off-by: Dimitris Aragiorgis dim...@arrikto.com Reviewed-by: Paolo Bonzini pbonz...@redhat.com --- block.c |6 +++--- block/iscsi.c |2 +- block/raw-posix.c |4 ++-- 3 files changed, 6

[Qemu-block] [PATCH v2 4/5] raw-posix: Use DPRINTF for DEBUG_FLOPPY

Get rid of several #ifdef DEBUG_FLOPPY and substitute them with DPRINTF. Signed-off-by: Dimitris Aragiorgis dim...@arrikto.com --- block/raw-posix.c | 20 +--- 1 file changed, 5 insertions(+), 15 deletions(-) diff --git a/block/raw-posix.c b/block/raw-posix.c index

[Qemu-block] [PATCH v2 2/5] Fix migration in case of scsi-generic

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,

[Qemu-block] [PATCH v2 3/5] raw-posix: DPRINTF instead of DEBUG_BLOCK_PRINT

Building the QEMU tools fails if we #define DEBUG_BLOCK inside block/raw-posix.c. Here instead of adding qemu-log.o in block-obj-y so that DEBUG_BLOCK_PRINT can be used, we substitute the latter with a simple DPRINTF(). Signed-off-by: Dimitris Aragiorgis dim...@arrikto.com --- block/raw-posix.c

Re: [Qemu-block] [Qemu-devel] [PATCH 01/34] qdict: Add qdict_array_entries()

On 05/08/2015 11:21 AM, Kevin Wolf wrote: Signed-off-by: Kevin Wolf kw...@redhat.com --- Might want to include mention of what it will be used for in the commit body. include/qapi/qmp/qdict.h | 1 + qobject/qdict.c | 68 +--- 2 files

Re: [Qemu-block] [Qemu-devel] [PATCH 03/34] quorum: Use bdrv_open_image()

On 05/08/2015 11:21 AM, Kevin Wolf wrote: Besides standardising on a single interface for opening child nodes, this simplifies the .bdrv_open() implementation of the quorum block driver by using block layer functionality for handling BlockdevRefs. Signed-off-by: Kevin Wolf kw...@redhat.com

Re: [Qemu-block] [Qemu-devel] [PATCH v2 0/3] block: Warn about usage of growing formats over non-growable protocols

On 08.05.2015 12:08, Kevin Wolf wrote: Am 07.05.2015 um 16:50 hat Paolo Bonzini geschrieben: On 07/05/2015 16:34, Kevin Wolf wrote: Am 07.05.2015 um 16:16 hat Paolo Bonzini geschrieben: On 07/05/2015 16:07, Kevin Wolf wrote: This is not right for two reasons: The first is that this is

Re: [Qemu-block] [PATCH v3] block/vdi: Use bdrv_flush after metadata updates

On 07.05.2015 06:04, Zhe Qiu wrote: From: phoeagon phoea...@gmail.com In reference to b0ad5a455d7e5352d4c86ba945112011dbeadfb8~078a458e077d6b0db262c4b05fee51d01de2d1d2, metadata writes to qcow2/cow/qcow/vpc/vmdk are all synced prior to succeeding writes. Only when write is successful that

Re: [Qemu-block] [Qemu-devel] [PATCH v3 01/10] qapi: Add transaction support to block-dirty-bitmap operations

On Thu, May 07, 2015 at 01:22:26PM -0400, John Snow wrote: On 05/07/2015 10:54 AM, Stefan Hajnoczi wrote: On Wed, Apr 22, 2015 at 08:04:44PM -0400, John Snow wrote: +static void block_dirty_bitmap_clear_prepare(BlkTransactionState *common, +

Re: [Qemu-block] [Qemu-devel] [PATCH 05/34] block: Use macro for cache option names

On 05/08/2015 11:21 AM, Kevin Wolf wrote: Signed-off-by: Kevin Wolf kw...@redhat.com --- blockdev.c| 24 include/block/block.h | 8 2 files changed, 20 insertions(+), 12 deletions(-) Reviewed-by: Eric Blake ebl...@redhat.com -- Eric Blake

Re: [Qemu-block] [Qemu-devel] [PATCH 06/34] block: Use QemuOpts in bdrv_open_common()

On 05/08/2015 11:21 AM, Kevin Wolf wrote: Instead of manually parsing options and then deleting them from the options QDict, just use QemuOpts like most other places that deal with block device options. More options will be added there and then QemuOpts is a lot more managable than

Re: [Qemu-block] [PATCH 2/4] block: Use bdrv_is_sg() everywhere

On 08/05/2015 13:38, Dimitris Aragiorgis wrote: Instead of checking bs-sg use bdrv_is_sg() consistently throughout the code. Signed-off-by: Dimitris Aragiorgis dim...@arrikto.com --- block.c |6 +++--- block/iscsi.c |2 +- block/raw-posix.c |4 ++-- 3 files

Re: [Qemu-block] [PATCH 1/4] Fix migration in case of scsi-generic

On 08/05/2015 13:38, Dimitris Aragiorgis wrote: 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.

Re: [Qemu-block] [PATCH] qcow2: do lazy allocation of the L2 cache

On Fri 08 May 2015 11:47:00 AM CEST, Kevin Wolf wrote: There's also the problem that with a single chunk of memory for all cache tables it's not so easy to free individual entries. That's one of the reasons why I suggested to fix the problem by using mmap() for the individual entries rather

Re: [Qemu-block] [PATCH v3] block/vdi: Use bdrv_flush after metadata updates

In case of correctness, lacking a sync here does not introduce data corruption I can think of. But this reduces the volatile window during which the metadata changes are NOT guaranteed on disk. Without a barrier, in case of power loss you may end up with the bitmap changes on disk and not the

Re: [Qemu-block] [PATCH v4] block/vdi: Use bdrv_flush after metadata updates

Thanks. Dbench does not logically allocate new disk space all the time, because it's a FS level benchmark that creates file and deletes them. Therefore it also depends on the guest FS, say, a btrfs guest FS allocates about 1.8x space of that from EXT4, due to its COW nature. It does cause the FS

Re: [Qemu-block] [PATCH v4] block/vdi: Use bdrv_flush after metadata updates

BTW, how do you usually measure the time to install a Linux distro within? Most distros ISOs do NOT have unattended installation ISOs in place. (True I can bake my own ISOs for this...) But do you have any ISOs made ready for this purpose? On Sat, May 9, 2015 at 11:54 AM phoeagon

[Qemu-block] [PATCH 4/4] block: Include qemu-log.o in block-obj-y

Building the QEMU tools fails if we #define DEBUG_BLOCK inside block/raw-posix.c. This happens because qemu-log.o is missing from block-obj-y, which causes the link to fail. Fix this. Signed-off-by: Dimitris Aragiorgis dim...@arrikto.com --- Makefile.objs |2 +- 1 file changed, 1

[Qemu-block] [PATCH 0/4] Some fixes related to scsi-generic

Hi all, These four patches make slight changes to the way QEMU handles SCSI generic devices to fix a number of small problems. I am sending them against the master branch, since I don't know if they can be considered bugfixes. Thanks, dimara Dimitris Aragiorgis (4): Fix migration in case of

[Qemu-block] [PATCH 3/4] raw-posix: Introduce hdev_is_sg()

Until now, an SG device was identified only by checking if its path started with /dev/sg. Then, hdev_open() set bs-sg accordingly. This is very fragile, e.g. it fails with symlinks or relative paths. We should rely on the actual properties of the device instead of the specified file path. Test

[Qemu-block] [PATCH 1/4] Fix migration in case of scsi-generic

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,

Re: [Qemu-block] [PATCH v3] block/vdi: Use bdrv_flush after metadata updates

Am 08.05.2015 um 13:50 hat phoeagon geschrieben: In case of correctness, lacking a sync here does not introduce data corruption I can think of. But this reduces the volatile window during which the metadata changes are NOT guaranteed on disk. Without a barrier, in case of power loss you may

Re: [Qemu-block] [Qemu-devel] [PATCH 09/34] block: Add BlockDriverState.inherits_from

On 05/08/2015 11:21 AM, Kevin Wolf wrote: Currently, the block layer assumes that any block node can have only one parent, and if it has a parent, that it inherits some options/flags from this parent. This is not true any more: With references used in block device creation, a single node

Re: [Qemu-block] [Qemu-devel] [PATCH v2 3/5] raw-posix: DPRINTF instead of DEBUG_BLOCK_PRINT

On 05/08/2015 11:47 AM, Dimitris Aragiorgis wrote: Building the QEMU tools fails if we #define DEBUG_BLOCK inside block/raw-posix.c. Here instead of adding qemu-log.o in block-obj-y so that DEBUG_BLOCK_PRINT can be used, we substitute the latter with a simple DPRINTF(). Signed-off-by: