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2011-10-03trace: add arguments to bdrv_co_io_em() trace eventStefan Hajnoczi
It is useful to know the BlockDriverState as well as the sector_num/nb_sectors of an emulated .bdrv_co_*() request. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-10-03trace: trace bdrv_open_common()Stefan Hajnoczi
bdrv_open_common() is a useful point to trace since it reveals the filename and block driver for a given BlockDriverState. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-09-12block: New change_media_cb() parameter loadMarkus Armbruster
To let device models distinguish between eject and load. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12block: Reset buffer alignment on detachMarkus Armbruster
BlockDriverState member buffer_alignment is initially 512. The device model may set them, with bdrv_set_buffer_alignment(). If the device model gets detached (hot unplug), the device's alignment is left behind. Only okay because device hot unplug automatically destroys the BlockDriverState. But that's a questionable feature, best not to rely on it. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12block: New bdrv_set_buffer_alignment()Markus Armbruster
Device models should be able to set it without an unclean include of block_int.h. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12block: Show whether the virtual tray is open in info blockMarkus Armbruster
Need to ask the device, so this requires new BlockDevOps member is_tray_open(). Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12block: Drop BlockDriverState member removableMarkus Armbruster
It's a confused mess (see previous commit). No users remain. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12block: Clean up remaining users of "removable"Markus Armbruster
BlockDriverState member removable is a confused mess. It is true when an ide-cd, scsi-cd or floppy qdev is attached, or when the BlockDriverState was created with -drive if={floppy,sd} or -drive if={ide,scsi,xen,none},media=cdrom ("created removable"), except when an ide-hd, scsi-hd, scsi-generic or virtio-blk qdev is attached. Three users remain: 1. eject_device(), via bdrv_is_removable() uses it to determine whether a block device can eject media. 2. bdrv_info() is monitor command "info block". QMP documentation says "true if the device is removable, false otherwise". From the monitor user's point of view, the only sensible interpretation of "is removable" is "can eject media with monitor commands eject and change". A block device can eject media unless a device is attached that doesn't support it. Switch the two users over to new bdrv_dev_has_removable_media() that returns exactly that. 3. bdrv_getlength() uses to suppress its length cache when media can change (see commit 46a4e4e6). Media change is either monitor command change (updates the length cache), monitor command eject (doesn't update the length cache, easily fixable), or physical media change (invalidates length cache, not so easily fixable). I'm refraining from improving anything here, because this series is long enough already. Instead, I simply switch it over to bdrv_dev_has_removable_media() as well. This changes the behavior of the length cache and of monitor commands eject and change in two cases: a. drive not created removable, no device attached The commit makes the drive removable, and defeats the length cache. Example: -drive if=none b. drive created removable, but the attached drive is non-removable, and doesn't call bdrv_set_removable(..., 0) (most devices don't) The commit makes the drive non-removable, and enables the length cache. Example: -drive if=xen,media=cdrom -M xenpv The other non-removable devices that don't call bdrv_set_removable() can't currently use a drive created removable, either because they aren't qdevified, or because they lack a drive property. Won't stay that way. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12block: Rename bdrv_set_locked() to bdrv_lock_medium()Markus Armbruster
While there, make the locked parameter bool. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12block: Drop medium lock tracking, ask device models insteadMarkus Armbruster
Requires new BlockDevOps member is_medium_locked(). Implement for IDE and SCSI CD-ROMs. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12block: Leave enforcing tray lock to device modelsMarkus Armbruster
The device model knows best when to accept the guest's eject command. No need to detour through the block layer. bdrv_eject() can't fail anymore. Make it void. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12block: Drop tray status tracking, no longer usedMarkus Armbruster
Commit 4be9762a is now completely redone. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12block: Revert entanglement of bdrv_is_inserted() with tray statusMarkus Armbruster
Commit 4be9762a changed bdrv_is_inserted() to fail when the tray is open. Unfortunately, there are two different kinds of users, with conflicting needs. 1. Device models using bdrv_eject(), currently ide-cd and scsi-cd. They expect bdrv_is_inserted() to reflect the tray status. Commit 4be9762a makes them happy. 2. Code that wants to know whether a BlockDriverState has media, such as find_image_format(), bdrv_flush_all(). Commit 4be9762a makes them unhappy. In particular, it breaks flush on VM stop for media ejected by the guest. Revert the change to bdrv_is_inserted(). Check the tray status in the device models instead. Note on IDE: Since only ATAPI devices have a tray, and they don't accept ATA commands since the recent commit "ide: Reject ATA commands specific to drive kinds", checking in atapi.c suffices. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06savevm: Include writable devices with removable mediaMarkus Armbruster
savevm and loadvm silently ignore block devices with removable media, such as floppies and SD cards. Rolling back a VM to a previous checkpoint will *not* roll back writes to block devices with removable media. Moreover, bdrv_is_removable() is a confused mess, and wrong in at least one case: it considers "-drive if=xen,media=cdrom -M xenpv" removable. It'll be cleaned up later in this series. Read-only block devices are also ignored, but that's okay. Fix by ignoring only read-only block devices and empty block devices. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06block: Clean up bdrv_flush_all()Markus Armbruster
Change (!bdrv_is_removable(bs) || bdrv_is_inserted(bs)) to just bdrv_is_inserted(). Rationale: The value of bdrv_is_removable(bs) matters only when bdrv_is_inserted(bs) is false. bdrv_is_inserted(bs) is true when bs is open (bs->drv != NULL) and not an empty host drive (CD-ROM or floppy). Therefore, bdrv_is_removable(bs) matters only when: 1. bs is not open old: may call bdrv_flush(bs), which does nothing new: won't call 2. bs is an empty host drive old: may call bdrv_flush(bs), which calls driver method raw_flush(), which calls fdatasync() or equivalent, which can't do anything useful while the drive is empty new: won't call Result is bs->drv && !bdrv_is_read_only(bs) && bdrv_is_inserted(bs). bdrv_is_inserted(bs) implies bs->drv. Drop the redundant test. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06block: Leave tracking media change to device modelsMarkus Armbruster
hw/fdc.c is the only one that cares. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06block: Split change_cb() into change_media_cb(), resize_cb()Markus Armbruster
Multiplexing callbacks complicates matters needlessly. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06block: Generalize change_cb() to BlockDevOpsMarkus Armbruster
So we can more easily add device model callbacks. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06block: Attach non-qdev devices as wellMarkus Armbruster
For now, this just protects against programming errors like having the same drive back multiple non-qdev devices, or untimely bdrv_delete(). Later commits will add other interesting uses. While there, rename BlockDriverState member peer to dev, bdrv_attach() to bdrv_attach_dev(), bdrv_detach() to bdrv_detach_dev(), and bdrv_get_attached() to bdrv_get_attached_dev(). Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-03Use new macro QEMU_PACKED for packed structuresStefan Weil
Most changes were made using these commands: git grep -la '__attribute__((packed))'|xargs perl -pi -e 's/__attribute__\(\(packed\)\)/QEMU_PACKED/' git grep -la '__attribute__ ((packed))'|xargs perl -pi -e 's/__attribute__ \(\(packed\)\)/QEMU_PACKED/' git grep -la '__attribute__((__packed__))'|xargs perl -pi -e 's/__attribute__\(\(__packed__\)\)/QEMU_PACKED/' git grep -la '__attribute__ ((__packed__))'|xargs perl -pi -e 's/__attribute__ \(\(__packed__\)\)/QEMU_PACKED/' git grep -la '__attribute((packed))'|xargs perl -pi -e 's/__attribute\(\(packed\)\)/QEMU_PACKED/' Whitespace in linux-user/syscall_defs.h was fixed manually to avoid warnings from scripts/checkpatch.pl. Manual changes were also applied to hw/pc.c. I did not fix indentation with tabs in block/vvfat.c. The patch will show 4 errors with scripts/checkpatch.pl. Signed-off-by: Stefan Weil <weil@mail.berlios.de> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-08-26block: latency accountingChristoph Hellwig
Account the total latency for read/write/flush requests. This allows management tools to average it based on a snapshot of the nr ops counters and allow checking for SLAs or provide statistics. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-25block: explicit I/O accountingChristoph Hellwig
Decouple the I/O accounting from bdrv_aio_readv/writev/flush and make the hardware models call directly into the accounting helpers. This means: - we do not count internal requests from image formats in addition to guest originating I/O - we do not double count I/O ops if the device model handles it chunk wise - we only account I/O once it actuall is done - can extent I/O accounting to synchronous or coroutine I/O easily - implement I/O latency tracking easily (see the next patch) I've conveted the existing device model callers to the new model, device models that are using synchronous I/O and weren't accounted before haven't been updated yet. Also scsi hasn't been converted to the end-to-end accounting as I want to defer that after the pending scsi layer overhaul. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-23block: include flush requests in info blockstatsChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-23block: add cache=directsync parameter to -driveStefan Hajnoczi
This patch adds -drive cache=directsync for O_DIRECT | O_SYNC host file I/O with no disk write cache presented to the guest. This mode is useful when guests may not be sending flushes when appropriate and therefore leave data at risk in case of power failure. When cache=directsync is used, write operations are only completed to the guest when data is safely on disk. This new mode is like cache=writethrough but it bypasses the host page cache. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-23block: parse cache mode flags in a single placeStefan Hajnoczi
This patch introduces bdrv_parse_cache_flags() which sets open flags given a cache mode. Previously this was duplicated in blockdev.c and qemu-img.c. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-22fix code formatRobert Wang
Fix code format to make checkpatch.pl happy. Signed-off-by: Robert Wang <wdongxu@linux.vnet.ibm.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-20Use glib memory allocation and free functionsAnthony Liguori
qemu_malloc/qemu_free no longer exist after this commit. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-04block: Use bdrv_co_* instead of synchronous versions in coroutinesKevin Wolf
If we're already in a coroutine, there is no reason to use the synchronous version of block layer functions when a coroutine one exists. This makes bdrv_read/write/flush use bdrv_co_* when used inside a coroutine. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-02async: Remove AsyncContextKevin Wolf
The purpose of AsyncContexts was to protect qcow and qcow2 against reentrancy during an emulated bdrv_read/write (which includes a qemu_aio_wait() call and can run AIO callbacks of different requests if it weren't for AsyncContexts). Now both qcow and qcow2 are protected by CoMutexes and AsyncContexts can be removed. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-02block: Add bdrv_co_readv/writev emulationKevin Wolf
In order to be able to call bdrv_co_readv/writev for drivers that don't implement the functions natively, add an emulation that uses the AIO functions to implement them. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-02block: Emulate AIO functions with bdrv_co_readv/writevKevin Wolf
Use the bdrv_co_readv/writev callbacks to implement bdrv_aio_readv/writev and bdrv_read/write if a driver provides the coroutine version instead of the synchronous or AIO version. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-02block: Add bdrv_co_readv/writevKevin Wolf
Add new block driver callbacks bdrv_co_readv/writev, which work on a QEMUIOVector like bdrv_aio_*, but don't need a callback. The function may only be called inside a coroutine, so a block driver implementing this interface can yield instead of blocking during I/O. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-01block: Removed unused function bdrv_write_syncFrediano Ziglio
Signed-off-by: Frediano Ziglio <freddy77@gmail.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-01block: Don't let locked flag prevent medium loadMarkus Armbruster
Commit aea2a33c made bdrv_eject() obey the locked flag. Correct for medium eject (eject_flag set), incorrect for medium load (eject_flag clear). See MMC-5 Table 341 "Actions for Lock/Unlock/Eject". Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-01block: Make BlockDriver method bdrv_eject() return voidMarkus Armbruster
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: Reset device model callbacks on detachMarkus Armbruster
BlockDriverState members change_cb and change_opaque are initially null. The device model may set them, with bdrv_set_change_cb(). If the device model gets detached (hot unplug), they're left dangling. Only safe because device hot unplug automatically destroys the BlockDriverState. But that's a questionable feature, best not to rely on it. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19block: add bdrv_get_allocated_file_size() operationFam Zheng
qemu-img.c wants to count allocated file size of image. Previously it counts a single bs->file by 'stat' or Window API. As VMDK introduces multiple file support, the operation becomes format specific with platform specific meanwhile. The functions are moved to block/raw-{posix,win32}.c and qemu-img.c calls bdrv_get_allocated_file_size to count the bs. And also added VMDK code to count his own extents. Signed-off-by: Fam Zheng <famcool@gmail.com> Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08bdrv_img_create: Fix segfaultKevin Wolf
Block drivers that don't support creating images don't have a size option. Fail gracefully instead of segfaulting when trying to access the option's value. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08block: clarify the meaning of BDRV_O_NOCACHEChristoph Hellwig
Change BDRV_O_NOCACHE to only imply bypassing the host OS file cache, but no writeback semantics. All existing callers are changed to also specify BDRV_O_CACHE_WB to give them writeback semantics. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-05-19block: Remove type hint, it's guest matter, doesn't belong hereMarkus Armbruster
No users of bdrv_get_type_hint() left. bdrv_set_type_hint() can make the media removable by side effect. Make that explicit. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-05-19block QMP: Deprecate query-block's "type", drop info block's "type="Markus Armbruster
query-block's specification documents response member "type" with values "hd", "cdrom", "floppy", "unknown". Its value is unreliable: a block device used as floppy has type "floppy" if created with if=floppy, but type "hd" if created with if=none. That's because with if=none, the type is at best a declaration of intent: the drive can be connected to any guest device. Its type is really the guest device's business. Reporting it here is wrong. No known user of QMP uses "type". It's unlikely that any unknown users exist, because its value is useless unless you know how the block device was created. But then you also know the true value. Fixing the broken value risks breaking (hypothetical!) clients that somehow rely on the current behavior. Not fixing the value risks breaking (hypothetical!) clients that rely on the value to be accurate. Can't entirely avoid hypothetical lossage. Change the value to be always "unknown". This makes "info block" always report "type=unknown". Pointless. Change it to not report the type. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-05-08Fix typos in comments and code (occured -> occurred and related)Stefan Weil
The code changed here is an unused data type name (evt_flush_occurred). Signed-off-by: Stefan Weil <weil@mail.berlios.de> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-05-06Fix typo in code and commentsStefan Weil
Replace writeable -> writable Signed-off-by: Stefan Weil <weil@mail.berlios.de> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-04-07block: Do not cache device size for removable mediaStefan Hajnoczi
The block layer caches the device size to avoid doing lseek(fd, 0, SEEK_END) every time this value is needed. For removable media the device size becomes stale if a new medium is inserted. This patch simply prevents device size caching for removable media. A smarter solution is to update the cached device size when a new medium is inserted. Given that there are currently bugs with CD-ROM media change I do not want to implement that approach until we've gotten things correct first. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-04-07trace: Trace bdrv_set_locked()Stefan Hajnoczi
It can be handy to know when the guest locks/unlocks the CD-ROM tray. This trace event makes that possible. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-04-07Do not delete BlockDriverState when deleting the driveRyan Harper
When removing a drive from the host-side via drive_del we currently have the following path: drive_del qemu_aio_flush() bdrv_close() // zaps bs->drv, which makes any subsequent I/O get // dropped. Works as designed drive_uninit() bdrv_delete() // frees the bs. Since the device is still connected to // bs, any subsequent I/O is a use-after-free. The value of bs->drv becomes unpredictable on free. As long as it remains null, I/O still gets dropped, however it could become non-null at any point after the free resulting SEGVs or other QEMU state corruption. To resolve this issue as simply as possible, we can chose to not actually delete the BlockDriverState pointer. Since bdrv_close() handles setting the drv pointer to NULL, we just need to remove the BlockDriverState from the QLIST that is used to enumerate the block devices. This is currently handled within bdrv_delete, so move this into its own function, bdrv_make_anon(). The result is that we can now invoke drive_del, this closes the file descriptors and sets BlockDriverState->drv to NULL which prevents futher IO to the device, and since we do not free BlockDriverState, we don't have to worry about the copy retained in the block devices. We also don't attempt to remove the qdev property since we are no longer deleting the BlockDriverState on drives with associated drives. This also allows for removing Drives with no devices associated either. Reported-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Ryan Harper <ryanh@us.ibm.com> Acked-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-03-15Don't allow multiwrites against a block device without underlying mediumRyan Harper
If the block device has been closed, we no longer have a medium to submit IO against, check for this before submitting io. This prevents a segfault further in the code where we dereference elements of the block driver. Signed-off-by: Ryan Harper <ryanh@us.ibm.com> Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-03-07trace: Trace bdrv_aio_flush()Stefan Hajnoczi
Add a trace event for bdrv_aio_flush() to complement the existing bdrv_aio_readv() and bdrv_aio_writev() events. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-02-20fdc: move floppy geometry guessing to block.cBlue Swirl
Other geometry guessing functions already reside in block.c. Remove some unused or debugging only fields. Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-02-07block: enable in_use flagMarcelo Tosatti
Set block device in use during block migration, disallow drive_del and bdrv_truncate for in use devices. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>