summaryrefslogtreecommitdiff
path: root/block/raw.c
AgeCommit message (Collapse)AuthorFilesLines
2012-09-24block: raw image file reopenJeff Cody1-0/+10
These are the stubs for the file reopen drivers for the raw format. There is currently nothing that needs to be done by the raw driver in reopen. Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-07-09raw: hook into blkdebugPaolo Bonzini1-0/+2
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-06-15block: implement is_allocated for rawPaolo Bonzini1-0/+8
Either FIEMAP, or SEEK_DATA+SEEK_HOLE can be used to implement the is_allocated callback for raw files. On Linux ext4, btrfs and XFS all support it. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-04-05block: push recursive flushing up from driversPaolo Bonzini1-6/+0
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-02-22block: bdrv_eject(): Make eject_flag a real boolLuiz Capitulino1-1/+1
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Acked-by: Kevin Wolf <kwolf@redhat.com>
2011-11-11block: Rename bdrv_co_flush to bdrv_co_flush_to_diskKevin Wolf1-4/+4
There are two different types of flush that you can do: Flushing one level up to the OS (i.e. writing data to the host page cache) or flushing it all the way down to the disk. The existing functions flush to the disk, reflect this in the function name. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21block: add bdrv_co_discard and bdrv_aio_discard supportPaolo Bonzini1-4/+6
This similarly adds support for coroutine and asynchronous discard. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21block: drop redundant bdrv_flush implementationStefan Hajnoczi1-10/+3
Block drivers now only need to provide either of .bdrv_co_flush, .bdrv_aio_flush() or for legacy drivers .bdrv_flush(). Remove the redundant .bdrv_flush() implementations. [Paolo Bonzini: change raw driver to bdrv_co_flush] Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-14block: use coroutine interface for raw formatStefan Hajnoczi1-24/+8
The raw format delegates all operations to bs->file (the protocol). Previously this block driver exposed both sync and aio interfaces. Since the block layer now works in terms of coroutines, expose the coroutine interfaces and drop the others. This avoids unnecessary emulation of sync and aio interfaces. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12block: Rename bdrv_set_locked() to bdrv_lock_medium()Markus Armbruster1-3/+3
While there, make the locked parameter bool. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06block/raw: Fix to forward method bdrv_media_changed()Markus Armbruster1-0/+7
Block driver "raw" forwards most methods to the underlying block driver. However, it doesn't implement method bdrv_media_changed(). Makes bdrv_media_changed() always return -ENOTSUP. I believe -fda /dev/fd0 gives you raw over host_floppy, and disk change detection (fdc register 7 bit 7) is broken. Testing my theory requires a computer museum, though. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-20Use glib memory allocation and free functionsAnthony Liguori1-1/+1
qemu_malloc/qemu_free no longer exist after this commit. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-01block: Make BlockDriver method bdrv_eject() return voidMarkus Armbruster1-2/+2
Callees always return 0, except for FreeBSD's cdrom_eject(), which returns -ENOTSUP when the device is in a terminally wedged state. The only caller is bdrv_eject(), and it maps -ENOTSUP to 0 since commit 4be9762a. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-01block: Make BlockDriver method bdrv_set_locked() return voidMarkus Armbruster1-2/+1
The only caller is bdrv_set_locked(), and it ignores the value. Callees always return 0, except for FreeBSD's cdrom_set_locked(), which returns -ENOTSUP when the device is in a terminally wedged state. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-12-17block: add discard supportChristoph Hellwig1-0/+6
Add a new bdrv_discard method to free blocks in a mapping image, and a new drive property to set the granularity for these discard. If no discard granularity support is set discard support is disabled. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-11-04block: Allow bdrv_flush to return errorsKevin Wolf1-2/+2
This changes bdrv_flush to return 0 on success and -errno in case of failure. It's a requirement for implementing proper error handle in users of bdrv_flush. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2010-09-08Revert "Make default invocation of block drivers safer (v3)"Anthony Liguori1-130/+0
This reverts commit 79368c81bf8cf93864d7afc88b81b05d8f0a2c90. Conflicts: block.c I haven't been able to come up with a solution yet for the corruption caused by unaligned requests from the IDE disk so revert until a solution can be written. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-08-03block: Fix bdrv_has_zero_initKevin Wolf1-0/+6
Assuming that any image on a block device is not properly zero-initialized is actually wrong: Only raw images have this problem. Any other image format shouldn't care about it, they initialize everything properly themselves. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-07-15Make default invocation of block drivers safer (v3)Anthony Liguori1-0/+130
CVE-2008-2004 described a vulnerability in QEMU whereas a malicious user could trick the block probing code into accessing arbitrary files in a guest. To mitigate this, we added an explicit format parameter to -drive which disabling block probing. Fast forward to today, and the vast majority of users do not use this parameter. libvirt does not use this by default nor does virt-manager. Most users want block probing so we should try to make it safer. This patch adds some logic to the raw device which attempts to detect a write operation to the beginning of a raw device. If the first 4 bytes happen to match an image file that has a backing file that we support, it scrubs the signature to all zeros. If a user specifies an explicit format parameter, this behavior is disabled. I contend that while a legitimate guest could write such a signature to the header, we would behave incorrectly anyway upon the next invocation of QEMU. This simply changes the incorrect behavior to not involve a security vulnerability. I've tested this pretty extensively both in the positive and negative case. I'm not 100% confident in the block layer's ability to deal with zero sized writes particularly with respect to the aio functions so some additional eyes would be appreciated. Even in the case of a single sector write, we have to make sure to invoked the completion from a bottom half so just removing the zero sized write is not an option. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-05-03block: Open the underlying image file in generic codeKevin Wolf1-45/+18
Format drivers shouldn't need to bother with things like file names, but rather just get an open BlockDriverState for the underlying protocol. This patch introduces this behaviour for bdrv_open implementation. For protocols which need to access the filename to open their file/device/connection/... a new callback bdrv_file_open is introduced which doesn't get an underlying file opened. For now, also some of the more obscure formats use bdrv_file_open because they open() the file themselves instead of using the block.c functions. They need to be fixed in later patches. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-03block: separate raw images from the file protocolChristoph Hellwig1-0/+171
We're running into various problems because the "raw" file access, which is used internally by the various image formats is entangled with the "raw" image format, which maps the VM view 1:1 to a file system. This patch renames the raw file backends to the file protocol which is treated like other protocols (e.g. nbd and http) and adds a new "raw" image format which is just a wrapper around calls to the underlying protocol. The patch is surprisingly simple, besides changing the probing logical in block.c to only look for image formats when using bdrv_open and renaming of the old raw protocols to file there's almost nothing in there. For creating images, a new bdrv_create_file is introduced which guesses the protocol to use. This allows using qemu-img create -f raw (or just using the default) for both files and host devices. Converting the other format drivers to use this function to create their images is left for later patches. The only issues still open are in the handling of the host devices. Firstly in current qemu we can specifiy the host* format names on various command line acceping images, but the new code can't do that without adding some translation. Second the layering breaks the no_zero_init flag in the BlockDriver used by qemu-img. I'm not happy how this is done per-driver instead of per-state so I'll prepare a separate patch to clean this up. There's some more cleanup opportunity after this patch, e.g. using separate lists and registration functions for image formats vs protocols and maybe even host drivers, but this can be done at a later stage. Also there's a check for protocol in bdrv_open for the BDRV_O_SNAPSHOT case that I don't quite understand, but which I fear won't work as expected - possibly even before this patch. Note that this patch requires various recent block patches from Kevin and me, which should all be in his block queue. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com>