aboutsummaryrefslogtreecommitdiffstats
path: root/block.c
AgeCommit message (Collapse)AuthorFilesLines
2010-01-26block: avoid creating too large iovecs in multiwrite_mergeChristoph Hellwig1-0/+4
If we go over the maximum number of iovecs support by syscall we get back EINVAL from the kernel which translate to I/O errors for the guest. Add a MAX_IOV defintion for platforms that don't have it. For now we use the same 1024 define that's used on Linux and various other platforms, but until the windows block backend implements some kind of vectored I/O it doesn't matter. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-26win32: pair qemu_memalign() with qemu_vfree()Herve Poussineau1-1/+1
Win32 suffers from a very big memory leak when dealing with SCSI devices. Each read/write request allocates memory with qemu_memalign (ie VirtualAlloc) but frees it with qemu_free (ie free). Pair all qemu_memalign() calls with qemu_vfree() to prevent such leaks. Signed-off-by: Herve Poussineau <hpoussin@reactos.org> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-26block: clean up bdrv_open2 structure a bitChristoph Hellwig1-12/+19
Check the whitelist as early as possible instead of continuing the setup, and move all the error handling code to the end of the function. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-26No need anymoe for bdrv_set_read_onlyNaphtali Sprei1-7/+0
Signed-off-by: Naphtali Sprei <nsprei@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-26block: Return original error codes in bdrv_pread/writeKevin Wolf1-16/+18
Don't assume -EIO but return the real error. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-20Revert "block: prevent multiwrite_merge from creating too large iovecs"Anthony Liguori1-4/+0
This reverts commit 0076bc0c1d93adcbc7f1af184e04902cf37e9ab8. Kevin Wolf pointed out that this breaks the mingw32 build. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-20block: prevent multiwrite_merge from creating too large iovecsChristoph Hellwig1-0/+4
If we go over the maximum number of iovecs support by syscall we get back EINVAL from the kernel which translate to I/O errors for the guest. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-20block: fix cache flushing in bdrv_commitChristoph Hellwig1-3/+6
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-20Disable fall-back to read-only when cannot open drive's file for read-writeNaphtali Sprei1-6/+0
Signed-off-by: Naphtali Sprei <nsprei@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-20Clean-up a little bit the RW related bits of BDRV_O_FLAGS. BDRV_O_RDONLY ↵Naphtali Sprei1-14/+17
gone (and so is BDRV_O_ACCESS). Default value for bdrv_flags (0/zero) is READ-ONLY. Need to explicitly request READ-WRITE. Instead of using the field 'readonly' of the BlockDriverState struct for passing the request, pass the request in the flags parameter to the function. Signed-off-by: Naphtali Sprei <nsprei@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-13block: flush backing_hd in the right placeChristoph Hellwig1-10/+7
The backing device is only modified from bdrv_commit. So instead of flushing it every time bdrv_flush is called for the front-end device only flush it after we're written data to it in bdrv_commit. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-13block: Add bdrv_change_backing_fileKevin Wolf1-0/+20
Introduce the functions needed to change the backing file of an image. The function is implemented for qcow2. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-13block: Introduce BDRV_O_NO_BACKINGKevin Wolf1-2/+2
If an image references a backing file that doesn't exist, qemu-img info fails to open this image. Exactly in this case the info would be valuable, though: the user might want to find out which file is missing. This patch introduces a BDRV_O_NO_BACKING flag to ignore the backing file when opening the image. qemu-img info is the first user and provides info now even if the backing file is invalid. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-12-25block.c: fix warning with _FORTIFY_SOURCEKirill A. Shutemov1-2/+2
CC block.o cc1: warnings being treated as errors block.c: In function 'bdrv_open2': block.c:400: error: ignoring return value of 'realpath', declared with attribute warn_unused_result Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2009-12-12block: Convert bdrv_info_stats() to QObjectLuiz Capitulino1-12/+72
Each device statistic information is stored in a QDict and the returned QObject is a QList of all devices. This commit should not change user output. Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-12-12block: Convert bdrv_info() to QObjectLuiz Capitulino1-20/+103
Each block device information is stored in a QDict and the returned QObject is a QList of all devices. This commit should not change user output. Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-12-03block migration: Cleanup dirty tracking codeJan Kiszka1-20/+24
This switches the dirty bitmap to a true bitmap, reducing its footprint (specifically in caches). It moreover fixes off-by-one bugs in set_dirty_bitmap (nb_sectors+1 were marked) and bdrv_get_dirty (limit check allowed one sector behind end of drive). And is drops redundant dirty_tracking field from BlockDriverState. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-12-03block migration: Rework constants APIJan Kiszka1-35/+25
Instead of duplicating the definition of constants or introducing trivial retrieval functions move the SECTOR constants into the public block API. This also obsoletes sector_per_block in BlkMigState. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-12-03block migration: Fix coding style and whitespacesJan Kiszka1-23/+26
No functional changes. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-11-17Expose a mechanism to trace block writeslirans@il.ibm.com1-1/+77
To support live migration without shared storage we need to be able to trace writes to disk while migrating. This Patch expose dirty block tracking per device to be polled from upper layer. Changes from v4: - Register dirty tracking for each block device. - Minor coding style issues. - Block.c will now manage a dirty bitmap per device once bdrv_set_dirty_tracking() is called. Bitmap is polled by the upper layer (block-migration.c). Signed-off-by: Liran Schour <lirans@il.ibm.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-11-09Configurable block format whitelistMarkus Armbruster1-1/+37
We have code for a quite a few block formats. While I trust that all of these formats are useful at least for some people in some circumstances, some of them are of a kind that friends don't let friends use in production. This patch provides an optional block format whitelist, default off. If a whitelist is configured with --block-drv-whitelist, QEMU proper can use only whitelisted formats. Other programs, like qemu-img, are not affected. Drivers for formats off the whitelist still participate in format probing, to ensure all programs probe exactly the same. Without that, QEMU proper would be prone to treat images with a format off the whitelist as raw when the image's format is probed. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-11-09Added readonly flag to -drive commandNaphtali Sprei1-4/+15
This is a slightly revised patch for adding readonly flag to the -drive command. Even though this patch is "stand-alone", it assumes a previous related patch (in Anthony staging tree), that passes the readonly attribute of the drive to the guest OS, applied first. This enables sharing same image between guests, with readonly access. Implementaion mark the drive as read_only and changes the flags when actually opening the file. The readonly attribute of a qcow also passed to it's base file. For ide that cannot pass the readonly attribute to the guest OS, disallow the readonly flag. Also, return error code from bdrv_truncate for readonly drive. Signed-off-by: Naphtali Sprei <nsprei@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-10-27block: Use new AsyncContext for bdrv_read/write emulationKevin Wolf1-4/+18
bdrv_read/write emulation is used as the perfect example why we need something like AsyncContexts. So maybe they better start using it. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-09-12Fix sys-queue.h conflict for goodBlue Swirl1-5/+1
Problem: Our file sys-queue.h is a copy of the BSD file, but there are some additions and it's not entirely compatible. Because of that, there have been conflicts with system headers on BSD systems. Some hacks have been introduced in the commits 15cc9235840a22c289edbe064a9b3c19c5f49896, f40d753718c72693c5f520f0d9899f6e50395e94, 96555a96d724016e13190b28cffa3bc929ac60dc and 3990d09adf4463eca200ad964cc55643c33feb50 but the fixes were fragile. Solution: Avoid the conflict entirely by renaming the functions and the file. Revert the previous hacks. Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2009-09-11block: add aio_flush operationChristoph Hellwig1-0/+40
Instead stalling the VCPU while serving a cache flush try to do it asynchronously. Use our good old helper thread pool to issue an asynchronous fdatasync for raw-posix. Note that while Linux AIO implements a fdatasync operation it is not useful for us because it isn't actually implement in asynchronous fashion. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-09-11block: add enable_write_cache flagChristoph Hellwig1-0/+15
Add a enable_write_cache flag in the block driver state, and use it to decide if we claim to have a volatile write cache that needs controlled flushing from the guest. The flag is off if cache=writethrough is defined because O_DSYNC guarantees that every write goes to stable storage, and it is on for cache=none and cache=writeback. Both scsi-disk and ide now use the new flage, changing from their defaults of always off (ide) or always on (scsi-disk). Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-09-11Add bdrv_aio_multiwriteKevin Wolf1-0/+183
One performance problem of qcow2 during the initial image growth are sequential writes that are not cluster aligned. In this case, when a first requests requires to allocate a new cluster but writes only to the first couple of sectors in that cluster, the rest of the cluster is zeroed - just to be overwritten by the following second request that fills up the cluster. Let's try to merge sequential write requests to the same cluster, so we can avoid to write the zero padding to the disk in the first place. As a nice side effect, also other formats take advantage of dealing with less and larger requests. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-08-27raw-posix: add Linux native AIO supportChristoph Hellwig1-1/+2
Now that do have a nicer interface to work against we can add Linux native AIO support. It's an extremly thing layer just setting up an iocb for the io_submit system call in the submission path, and registering an eventfd with the qemu poll handler to do complete the iocbs directly from there. This started out based on Anthony's earlier AIO patch, but after estimated 42,000 rewrites and just as many build system changes there's not much left of it. To enable native kernel aio use the aio=native sub-command on the drive command line. I have also added an option to qemu-io to test the aio support without needing a guest. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-27rename HOST_BSD to CONFIG_BSDJuan Quintela1-2/+2
Signed-off-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-16replace bdrv_{get, put}_buffer with bdrv_{load, save}_vmstateChristoph Hellwig1-6/+8
The VM state offset is a concept internal to the image format. Replace the old bdrv_{get,put}_buffer method that require an index into the image file that is constructed from the VM state offset and an offset into the vmstate with the bdrv_{load,save}_vmstate that just take an offset into the VM state. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-10block: Clean up after deleting BHsAvi Kivity1-0/+2
Commit 6a7ad299 ("Call qemu_bh_delete at bdrv_aio_bh_cb") deletes emulated aio bottom halves to prevent endless accumulation. However, it leaves a stale ->bh pointer, which is then waited on when the aio is reused. Zeroing the pointer fixes the issue, allowing vmdk format images to be used. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-09Revert "support colon in filenames"Anthony Liguori1-17/+10
This reverts commit 707c0dbc97cddfe8d2441b8259c6c526d99f2dd8. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-01Fix missing strnlen problemsBlue Swirl1-1/+1
Fix missing strnlen (a GNU extension) problems by using qemu_strnlen used for user emulators also for system emulators. Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2009-06-29support colon in filenamesRam Pai1-10/+17
Problem: It is impossible to feed filenames with the character colon because qemu interprets such names as a protocol. For example filename scsi:0, is interpreted as a protocol by name "scsi". This patch allows user to espace colon characters. For example the above filename can now be expressed either as 'scsi\:0' or as file:scsi:0 anything following the "file:" tag is interpreted verbatin. However if "file:" tag is omitted then any colon characters in the string must be escaped using backslash. Here are couple of examples: scsi\:0\:abc is a local file scsi:0:abc http\://myweb is a local file by name http://myweb file:scsi:0:abc is a local file scsi:0:abc file:http://myweb is a local file by name http://myweb Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-06-16Prevent CD-ROM media eject while device is lockedMark McLoughlin1-1/+8
Section 10.8.25 ("START/STOP UNIT Command") of SFF-8020i states that if the device is locked we should refuse to eject if the device is locked. ASC_MEDIA_REMOVAL_PREVENTED is the appropriate return in this case. In order to stop itself from ejecting the media it is running from, Fedora's installer (anaconda) requires the CDROMEJECT ioctl() to fail if the drive has been previously locked. See also https://bugzilla.redhat.com/501412 Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-06-16Call qemu_bh_delete at bdrv_aio_bh_cb.Dor Laor1-2/+2
Also replave qemu_bh_cancel with qemu_bh_delete in bdrv_aio_cancel_em. Otherwise the bh will live forever in the bh list. Signed-off-by: Dor Laor <dor@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-06-15block: add bdrv_probe_device methodChristoph Hellwig1-32/+12
Add a bdrv_probe_device method to all BlockDriver instances implementing host devices to move matching of host device types into the actual drivers. For now we keep exacly the old matching behaviour based on the devices names, although we really should have better detetion methods based on device information in the future. Signed-off-by: Christoph Hellwig <hch@lst.de>
2009-06-15raw-posix: split hdev driversChristoph Hellwig1-17/+43
Instead of declaring one BlockDriver for all host devices declared one for each type: a generic one for normal disk devices, a Linux floppy driver and a CDROM driver for Linux and FreeBSD. This gets rid of a lot of messy ifdefs and switching based on the type in the various removal device methods. block.c grows a new method to find the correct host device driver based on OS-sepcific criteria, which will later into the actual drivers in a later patch in this series. Signed-off-by: Christoph Hellwig <hch@lst.de>
2009-05-27fully split aio_pool from BlockDriverChristoph Hellwig1-40/+25
Now that we have a separate aio pool structure we can remove those aio pool details from BlockDriver. Every driver supporting AIO now needs to declare a static AIOPool with the aiocb size and the cancellation method. This cleans up the current code considerably and will make it cleaner and more obvious to support two different aio implementations behind a single BlockDriver. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-05-27Drop bdrv_create2Kevin Wolf1-40/+15
This patch converts the remaining users of bdrv_create2 to bdrv_create and removes the now unused function. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-05-22Convert all block drivers to new bdrv_createKevin Wolf1-11/+33
Now we can make use of the newly introduced option structures. Instead of having bdrv_create carry more and more parameters (which are format specific in most cases), just pass a option structure as defined by the driver itself. bdrv_create2() contains an emulation of the old interface to simplify the transition. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-05-22Fix segv when passing an unknown protocolAnthony Liguori1-1/+1
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-05-14Convert block infrastructure to use new module init functionalityAnthony Liguori1-24/+11
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-05-08Improve block range checksKevin Wolf1-1/+6
This patch makes the range checks for block requests more strict: It fixes a potential integer overflow and checks for negative offsets. Also, it adds the check for compressed writes. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-04-22implement qemu_blockalign (Stefano Stabellini)aliguori1-1/+8
this patch adds a buffer_alignment field to BlockDriverState and implements a qemu_blockalign function that uses that field to allocate a memory aligned buffer to be used by the block driver. buffer_alignment is initialized to 512 but each block driver can set a different value (at the moment none of them do). This patch modifies ide.c, block-qcow.c, block-qcow2.c and block.c to use qemu_blockalign instead of qemu_memalign. There is only one place left that still uses qemu_memalign to allocate buffers used by block drivers that is posix-aio-compat:handle_aiocb_rw because it is not possible to get the BlockDriverState from that function. However I think it is not important because posix-aio-compat already deals with driver specific code so it is supposed to know its own needs. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7229 c046a42c-6fe2-441c-8c8c-71466251a162
2009-04-21Introduce bdrv_check (Kevin Wolf)aliguori1-0/+14
From: Kevin Wolf <kwolf@redhat.com> Introduce a new bdrv_check function pointer for block drivers. Modify qcow2 to return an error status in check_refcounts(), so it can implement bdrv_check. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7214 c046a42c-6fe2-441c-8c8c-71466251a162
2009-04-13Fix OpenSolaris gcc4 warnings: iovec type mismatches, missing 'static'blueswir11-1/+1
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7103 c046a42c-6fe2-441c-8c8c-71466251a162
2009-04-07native preadv/pwritev support (Christoph Hellwig)aliguori1-2/+1
This ties up the preadv/pwritev syscalls to qemu if they are declared in unistd.h. This is the case currently on at least NetBSD and OpenBSD and will hopefully soon be the case on Linux. Thanks to Blue Swirl and Gerd Hoffmann for the configure autodetection of preadv/pwritev. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7021 c046a42c-6fe2-441c-8c8c-71466251a162
2009-04-07push down vector linearization to posix-aio-compat.c (Christoph Hellwig)aliguori1-126/+70
Make all AIO requests vectored and defer linearization until the actual I/O thread. This prepares for using native preadv/pwritev. Also enables asynchronous direct I/O by handling that case in the I/O thread. Qcow and qcow2 propably want to be adopted to directly deal with multi-segment requests, but that can be implemented later. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7020 c046a42c-6fe2-441c-8c8c-71466251a162
2009-04-07remove bdrv_aio_read/bdrv_aio_write (Christoph Hellwig)aliguori1-2/+8
Always use the vectored APIs to reduce code churn once we switch the BlockDriver API to be vectored. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7019 c046a42c-6fe2-441c-8c8c-71466251a162