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2014-01-26ACPI: Fix AppleSMC _STA sizeGabriel L. Somlo2-8/+7
Minimize the storage used for AppleSMC's _STA (8bit), relying on ASL to implicitly convert it to the officially specified 32bit value. Signed-off-by: Gabriel Somlo <somlo@cmu.edu> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-01-26Add DSDT node for AppleSMCGabriel L. Somlo6-1/+29
AppleSMC (-device isa-applesmc) is required to boot OS X guests. OS X expects a SMC node to be present in the ACPI DSDT. This patch adds a SMC node to the DSDT, and dynamically patches the return value of SMC._STA to either 0x0B if the chip is present, or otherwise to 0x00, before booting the guest. Signed-off-by: Gabriel Somlo <somlo@cmu.edu> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-01-26Python-lang gdb script to extract x86_64 guest vmcore from qemu coredumpLaszlo Ersek1-0/+339
When qemu dies unexpectedly, for example in response to an explicit abort() call, or (more importantly) when an external signal is delivered to it that results in a coredump, sometimes it is useful to extract the guest vmcore from the qemu process' memory image. The guest vmcore might help understand an emulation problem in qemu, or help debug the guest. This script reimplements (and cuts many features of) the qmp_dump_guest_memory() command in gdb/Python, https://sourceware.org/gdb/current/onlinedocs/gdb/Python-API.html working off the saved memory image of the qemu process. The docstring in the patch (serving as gdb help text) describes the limitations relative to the QMP command. Dependencies of qmp_dump_guest_memory() have been reimplemented as needed. I sought to follow the general structure, sticking to original function names where possible. However, keeping it simple prevailed in some places. The patch has been tested with a 4 VCPU, 768 MB, RHEL-6.4 (2.6.32-358.el6.x86_64) guest: - The script printed > guest RAM blocks: > target_start target_end host_addr message count > ---------------- ---------------- ---------------- ------- ----- > 0000000000000000 00000000000a0000 00007f95d0000000 added 1 > 00000000000a0000 00000000000b0000 00007f960ac00000 added 2 > 00000000000c0000 00000000000ca000 00007f95d00c0000 added 3 > 00000000000ca000 00000000000cd000 00007f95d00ca000 joined 3 > 00000000000cd000 00000000000d0000 00007f95d00cd000 joined 3 > 00000000000d0000 00000000000f0000 00007f95d00d0000 joined 3 > 00000000000f0000 0000000000100000 00007f95d00f0000 joined 3 > 0000000000100000 0000000030000000 00007f95d0100000 joined 3 > 00000000fc000000 00000000fc800000 00007f960ac00000 added 4 > 00000000fffe0000 0000000100000000 00007f9618800000 added 5 > dumping range at 00007f95d0000000 for length 00000000000a0000 > dumping range at 00007f960ac00000 for length 0000000000010000 > dumping range at 00007f95d00c0000 for length 000000002ff40000 > dumping range at 00007f960ac00000 for length 0000000000800000 > dumping range at 00007f9618800000 for length 0000000000020000 - The vmcore was checked with "readelf", comparing the results against a vmcore written by qmp_dump_guest_memory(): > --- theirs 2013-09-12 17:38:59.797289404 +0200 > +++ mine 2013-09-12 17:39:03.820289404 +0200 > @@ -27,16 +27,16 @@ > Type Offset VirtAddr PhysAddr > FileSiz MemSiz Flags Align > NOTE 0x0000000000000190 0x0000000000000000 0x0000000000000000 > - 0x0000000000000ca0 0x0000000000000ca0 0 > - LOAD 0x0000000000000e30 0x0000000000000000 0x0000000000000000 > + 0x000000000000001c 0x000000000000001c 0 > + LOAD 0x00000000000001ac 0x0000000000000000 0x0000000000000000 > 0x00000000000a0000 0x00000000000a0000 0 > - LOAD 0x00000000000a0e30 0x0000000000000000 0x00000000000a0000 > + LOAD 0x00000000000a01ac 0x0000000000000000 0x00000000000a0000 > 0x0000000000010000 0x0000000000010000 0 > - LOAD 0x00000000000b0e30 0x0000000000000000 0x00000000000c0000 > + LOAD 0x00000000000b01ac 0x0000000000000000 0x00000000000c0000 > 0x000000002ff40000 0x000000002ff40000 0 > - LOAD 0x000000002fff0e30 0x0000000000000000 0x00000000fc000000 > + LOAD 0x000000002fff01ac 0x0000000000000000 0x00000000fc000000 > 0x0000000000800000 0x0000000000800000 0 > - LOAD 0x00000000307f0e30 0x0000000000000000 0x00000000fffe0000 > + LOAD 0x00000000307f01ac 0x0000000000000000 0x00000000fffe0000 > 0x0000000000020000 0x0000000000020000 0 > > There is no dynamic section in this file. > @@ -47,13 +47,6 @@ > > No version information found in this file. > > -Notes at offset 0x00000190 with length 0x00000ca0: > +Notes at offset 0x00000190 with length 0x0000001c: > Owner Data size Description > - CORE 0x00000150 NT_PRSTATUS (prstatus structure) > - CORE 0x00000150 NT_PRSTATUS (prstatus structure) > - CORE 0x00000150 NT_PRSTATUS (prstatus structure) > - CORE 0x00000150 NT_PRSTATUS (prstatus structure) > - QEMU 0x000001b0 Unknown note type: (0x00000000) > - QEMU 0x000001b0 Unknown note type: (0x00000000) > - QEMU 0x000001b0 Unknown note type: (0x00000000) > - QEMU 0x000001b0 Unknown note type: (0x00000000) > + NONE 0x00000005 Unknown note type: (0x00000000) - The vmcore was checked with "crash" too, again comparing the results against a vmcore written by qmp_dump_guest_memory(): > --- guest.vmcore.log2 2013-09-12 17:52:27.074289201 +0200 > +++ example.dump.log2 2013-09-12 17:52:15.904289203 +0200 > @@ -22,11 +22,11 @@ > This GDB was configured as "x86_64-unknown-linux-gnu"... > > KERNEL: /usr/lib/debug/lib/modules/2.6.32-358.el6.x86_64/vmlinux > - DUMPFILE: /home/lacos/tmp/guest.vmcore > + DUMPFILE: /home/lacos/tmp/example.dump > CPUS: 4 > - DATE: Thu Sep 12 17:16:11 2013 > - UPTIME: 00:01:09 > -LOAD AVERAGE: 0.07, 0.03, 0.00 > + DATE: Thu Sep 12 17:17:41 2013 > + UPTIME: 00:00:38 > +LOAD AVERAGE: 0.18, 0.05, 0.01 > TASKS: 130 > NODENAME: localhost.localdomain > RELEASE: 2.6.32-358.el6.x86_64 > @@ -38,12 +38,12 @@ > COMMAND: "swapper" > TASK: ffffffff81a8d020 (1 of 4) [THREAD_INFO: ffffffff81a00000] > CPU: 0 > - STATE: TASK_RUNNING (PANIC) > + STATE: TASK_RUNNING (ACTIVE) > + WARNING: panic task not found > > crash> bt > PID: 0 TASK: ffffffff81a8d020 CPU: 0 COMMAND: "swapper" > - #0 [ffffffff81a01ed0] default_idle at ffffffff8101495d > - #1 [ffffffff81a01ef0] cpu_idle at ffffffff81009fc6 > + #0 [ffffffff81a01ef0] cpu_idle at ffffffff81009fc6 > crash> task ffffffff81a8d020 > PID: 0 TASK: ffffffff81a8d020 CPU: 0 COMMAND: "swapper" > struct task_struct { > @@ -75,7 +75,7 @@ > prev = 0xffffffff81a8d080 > }, > on_rq = 0, > - exec_start = 8618466836, > + exec_start = 7469214014, > sum_exec_runtime = 0, > vruntime = 0, > prev_sum_exec_runtime = 0, > @@ -149,7 +149,7 @@ > }, > tasks = { > next = 0xffff88002d621948, > - prev = 0xffff880029618f28 > + prev = 0xffff880023b74488 > }, > pushable_tasks = { > prio = 140, > @@ -165,7 +165,7 @@ > } > }, > mm = 0x0, > - active_mm = 0xffff88002929b780, > + active_mm = 0xffff8800297eb980, > exit_state = 0, > exit_code = 0, > exit_signal = 0, > @@ -177,7 +177,7 @@ > sched_reset_on_fork = 0, > pid = 0, > tgid = 0, > - stack_canary = 2483693585637059287, > + stack_canary = 7266362296181431986, > real_parent = 0xffffffff81a8d020, > parent = 0xffffffff81a8d020, > children = { > @@ -224,14 +224,14 @@ > set_child_tid = 0x0, > clear_child_tid = 0x0, > utime = 0, > - stime = 3, > + stime = 2, > utimescaled = 0, > - stimescaled = 3, > + stimescaled = 2, > gtime = 0, > prev_utime = 0, > prev_stime = 0, > nvcsw = 0, > - nivcsw = 1000, > + nivcsw = 1764, > start_time = { > tv_sec = 0, > tv_nsec = 0 - <name_dropping>I asked for Dave Anderson's help with verifying the extracted vmcore, and his comments make me think I should post this.</name_dropping> Signed-off-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-01-24Merge remote-tracking branch 'qemu-kvm/uq/master' into stagingAnthony Liguori6-23/+145
* qemu-kvm/uq/master: kvm: always update the MPX model specific register KVM: fix addr type for KVM_IOEVENTFD KVM: Retry KVM_CREATE_VM on EINTR mempath prefault: fix off-by-one error kvm: x86: Separately write feature control MSR on reset roms: Flush icache when writing roms to guest memory target-i386: clear guest TSC on reset target-i386: do not special case TSC writeback target-i386: Intel MPX Conflicts: exec.c aliguori: fix trivial merge conflict in exec.c Signed-off-by: Anthony Liguori <aliguori@amazon.com>
2014-01-24Merge remote-tracking branch 'otubo/seccomp' into stagingAnthony Liguori1-1/+6
* otubo/seccomp: seccomp: add some basic shared memory syscalls to the whitelist seccomp: add mkdir() and fchmod() to the whitelist Message-id: 1390231004-18392-1-git-send-email-otubo@linux.vnet.ibm.com Signed-off-by: Anthony Liguori <aliguori@amazon.com>
2014-01-24Merge remote-tracking branch 'sweil/tags/for_anthony' into stagingAnthony Liguori1-3/+15
Initial patch for QEMU GTK support on Windows # gpg: Signature made Mon 20 Jan 2014 11:37:58 AM PST using RSA key ID FAD62069 # gpg: Can't check signature: public key not found * sweil/tags/for_anthony: gtk: Support keyboard translation for hosts running Windows Message-id: 1390246909-18757-1-git-send-email-sw@weilnetz.de Signed-off-by: Anthony Liguori <aliguori@amazon.com>
2014-01-24Merge remote-tracking branch 'kraxel/tags/pull-audio-2' into stagingAnthony Liguori1-0/+18
hda-codec: disable streams on reset # gpg: Signature made Tue 21 Jan 2014 02:17:12 AM PST using RSA key ID D3E87138 # gpg: Can't check signature: public key not found * kraxel/tags/pull-audio-2: hda-codec: disable streams on reset Message-id: 1390299589-5082-1-git-send-email-kraxel@redhat.com Signed-off-by: Anthony Liguori <aliguori@amazon.com>
2014-01-24Merge remote-tracking branch 'kraxel/tags/pull-usb-2' into stagingAnthony Liguori10-6/+305
usb core+hid: add support for microsoft os descriptors # gpg: Signature made Tue 21 Jan 2014 02:21:29 AM PST using RSA key ID D3E87138 # gpg: Can't check signature: public key not found * kraxel/tags/pull-usb-2: usb-hid: add microsoft os descriptor support usb: add support for microsoft os descriptors Message-id: 1390299772-5368-1-git-send-email-kraxel@redhat.com Signed-off-by: Anthony Liguori <aliguori@amazon.com>
2014-01-24Merge remote-tracking branch 'bonzini/scsi-next' into stagingAnthony Liguori4-1/+16
* bonzini/scsi-next: scsi: Support TEST UNIT READY in the dummy LUN0 block: add .bdrv_reopen_prepare() stub for iscsi virtio-scsi: Prevent assertion on missed events virtio-scsi: Cleanup of I/Os that never started scsi: Assign cancel_io vector for scsi_disk_emulate_ops Conflicts: block/iscsi.c aliguori: resolve trivial merge conflict in block/iscsi.c Signed-off-by: Anthony Liguori <aliguori@amazon.com>
2014-01-24Merge remote-tracking branch 'kwolf/tags/for-anthony' into stagingAnthony Liguori77-885/+3579
Block patches # gpg: Signature made Fri 24 Jan 2014 08:40:53 AM PST using RSA key ID C88F2FD6 # gpg: Can't check signature: public key not found * kwolf/tags/for-anthony: (93 commits) block: Switch bdrv_io_limits_intercept() to byte granularity qemu-iotests: Test pwritev RMW logic qemu-io: New command 'sleep' blkdebug: Make required alignment configurable iscsi: Set bs->request_alignment block: Make bdrv_pwrite() a bdrv_prwv_co() wrapper block: Make bdrv_pread() a bdrv_prwv_co() wrapper block: Change coroutine wrapper to byte granularity block: Assert serialisation assumptions in pwritev block: Align requests in bdrv_co_do_pwritev() block: Allow wait_serialising_requests() at any point block: Make overlap range for serialisation dynamic block: Generalise and optimise COR serialisation block: Make zero-after-EOF work with larger alignment block: Allow waiting for overlapping requests between begin/end block: Switch BdrvTrackedRequest to byte granularity block: Introduce bdrv_co_do_pwritev() block: write: Handle COR dependency after I/O throttling block: Introduce bdrv_aligned_pwritev() block: Introduce bdrv_co_do_preadv() ... Message-id: 1390584136-24703-1-git-send-email-kwolf@redhat.com Signed-off-by: Anthony Liguori <aliguori@amazon.com>
2014-01-24block: Switch bdrv_io_limits_intercept() to byte granularityKevin Wolf1-8/+5
Request sizes used to be rounded down to the next sector boundary, allowing to bypass the I/O limit. Now all requests are accounted for with their exact byte size. Reported-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2014-01-24qemu-iotests: Test pwritev RMW logicKevin Wolf6-0/+504
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2014-01-24qemu-io: New command 'sleep'Kevin Wolf1-0/+42
There is no easy way to check that a request correctly waits for a different request. With a sleep command we can at least approximate it. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-24blkdebug: Make required alignment configurableKevin Wolf2-0/+19
The new 'align' option of blkdebug can be used in order to emulate backends with a required 4k alignment on hosts which only really require 512 byte alignment. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-24iscsi: Set bs->request_alignmentPaolo Bonzini1-0/+1
The iSCSI backend already gets the block size from the READ CAPACITY command it sends. Save it so that the generic block layer gets it too. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2014-01-24block: Make bdrv_pwrite() a bdrv_prwv_co() wrapperKevin Wolf2-56/+9
Instead of implementing the alignment adjustment here, use the now existing functionality of bdrv_co_do_pwritev(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2014-01-24block: Make bdrv_pread() a bdrv_prwv_co() wrapperKevin Wolf1-36/+13
Instead of implementing the alignment adjustment here, use the now existing functionality of bdrv_co_do_preadv(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2014-01-24block: Change coroutine wrapper to byte granularityKevin Wolf1-22/+26
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2014-01-24block: Assert serialisation assumptions in pwritevKevin Wolf1-4/+12
If a request calls wait_serialising_requests() and actually has to wait in this function (i.e. a coroutine yield), other requests can run and previously read data (like the head or tail buffer) could become outdated. In this case, we would have to restart from the beginning to read in the updated data. However, we're lucky and don't actually need to do that: A request can only wait in the first call of wait_serialising_requests() because we mark it as serialising before that call, so any later requests would wait. So as we don't wait in practice, we don't have to reload the data. This is an important assumption that may not be broken or data corruption will happen. Document it with some assertions. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2014-01-24block: Align requests in bdrv_co_do_pwritev()Kevin Wolf1-1/+85
This patch changes bdrv_co_do_pwritev() to actually be what its name promises. If requests aren't properly aligned, it performs a RMW. Requests touching the same block are serialised against the RMW request. Further optimisation of this is possible by differentiating types of requests (concurrent reads should actually be okay here). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: Allow wait_serialising_requests() at any pointKevin Wolf2-3/+12
We can only have a single wait_serialising_requests() call per request because otherwise we can run into deadlocks where requests are waiting for each other. The same is true when wait_serialising_requests() is not at the very beginning of a request, so that other requests can be issued between the start of the tracking and wait_serialising_requests(). Fix this by changing wait_serialising_requests() to ignore requests that are already (directly or indirectly) waiting for the calling request. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: Make overlap range for serialisation dynamicKevin Wolf2-26/+31
Copy on Read wants to serialise with all requests touching the same cluster, so wait_serialising_requests() rounded to cluster boundaries. Other users like alignment RMW will have different requirements, though (requests touching the same sector), so make it dynamic. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: Generalise and optimise COR serialisationKevin Wolf2-21/+32
Change the API so that specific requests can be marked serialising. Only these requests are checked for overlaps then. This means that during a Copy on Read operation, not all requests overlapping other requests are serialised any more, but only those that actually overlap with the specific COR request. Also remove COR from function and variable names because this functionality can be useful in other contexts. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: Make zero-after-EOF work with larger alignmentKevin Wolf1-3/+4
Odd file sizes could make bdrv_aligned_preadv() shorten the request in non-aligned ways. Fix it by rounding to the required alignment instead of 512 bytes. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: Allow waiting for overlapping requests between begin/endKevin Wolf1-18/+20
Previously, it was not possible to use wait_for_overlapping_requests() between tracked_request_begin()/end() because it would wait for itself. Ignore the current request in the overlap check and run more of the bdrv_co_do_preadv/pwritev code with a BdrvTrackedRequest present. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: Switch BdrvTrackedRequest to byte granularityKevin Wolf3-21/+42
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: Introduce bdrv_co_do_pwritev()Kevin Wolf1-6/+18
This is going to become the bdrv_co_do_preadv() equivalent for writes. In this patch, however, just a function taking byte offsets is created, it doesn't align anything yet. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: write: Handle COR dependency after I/O throttlingKevin Wolf1-4/+4
First waiting for all COR requests to complete and calling the throttling function afterwards means that the request could be delayed and we still need to wait for the COR request even if it was issued only after the throttled write request. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: Introduce bdrv_aligned_pwritev()Kevin Wolf1-21/+41
This separates the part of bdrv_co_do_writev() that needs to happen before the request is modified to match the backend alignment, and a part that needs to be executed afterwards and passes the request to the BlockDriver. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: Introduce bdrv_co_do_preadv()Kevin Wolf1-6/+58
Similar to bdrv_pread(), which aligns byte-aligned request to 512 byte sectors, bdrv_co_do_preadv() takes a byte-aligned request and aligns it to the alignment specified in bs->request_alignment. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: Introduce bdrv_aligned_preadv()Kevin Wolf1-18/+43
This separates the part of bdrv_co_do_readv() that needs to happen before the request is modified to match the backend alignment, and a part that needs to be executed afterwards and passes the request to the BlockDriver. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2014-01-24raw: Probe required direct I/O alignmentPaolo Bonzini4-17/+132
Add a bs->request_alignment field that contains the required offset/length alignment for I/O requests and fill it in the raw block drivers. Use ioctls if possible, else see what alignment it takes for O_DIRECT to succeed. While at it, also expose the memory alignment requirements, which may be (and in practice are) different from the disk alignment requirements. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2014-01-24block: rename buffer_alignment to guest_block_sizePaolo Bonzini7-12/+12
The alignment field is now set to the value that is promised to the guest, rather than required by the host. The next patches will make QEMU aware of the host-provided values, so make this clear. The alignment is also not about memory buffers, but about the sectors on the disk, change the documentation of the field. At this point, the field is set by the device emulation, but completely ignored by the block layer. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: Don't use guest sector size for qemu_blockalign()Kevin Wolf3-3/+26
bs->buffer_alignment is set by the device emulation and contains the logical block size of the guest device. This isn't something that the block layer should know, and even less something to use for determining the right alignment of buffers to be used for the host. The new BlockLimits field opt_mem_alignment tells the qemu block layer the optimal alignment to be used so that no bounce buffer must be used in the driver. This patch may change the buffer alignment from 4k to 512 for all callers that used qemu_blockalign() with the top-level image format BlockDriverState. The value was never propagated to other levels in the tree, so in particular raw-posix never required anything else than 512. While on disks with 4k sectors direct I/O requires a 4k alignment, memory may still be okay when aligned to 512 byte boundaries. This is what must have happened in practice, because otherwise this would already have failed earlier. Therefore I don't expect regressions even with this intermediate state. Later, raw-posix can implement the hook and expose a different memory alignment requirement. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2014-01-24block: Detect unaligned length in bdrv_qiov_is_aligned()Kevin Wolf1-0/+3
For an O_DIRECT request to succeed, it's not only necessary that all base addresses in the qiov are aligned, but also that each length in it is aligned. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2014-01-24qemu_memalign: Allow small alignmentsKevin Wolf1-0/+5
The functions used by qemu_memalign() require an alignment that is at least sizeof(void*). Adjust it if it is too small. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoît Canet <benoit@irqsave.net>
2014-01-24block: Update BlockLimits when they might have changedKevin Wolf3-1/+7
When reopening with different flags, or when backing files disappear from the chain, the limits may change. Make sure they get updated in these cases. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoît Canet <benoit@irqsave.net>
2014-01-24block: Inherit opt_transfer_lengthKevin Wolf1-1/+19
When there is a format driver between the backend, it's not guaranteed that exposing the opt_transfer_length for the format driver results in the optimal requests (because of fragmentation etc.), but it can't make things worse, so let's just do it. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoît Canet <benoit@irqsave.net>
2014-01-24block: Move initialisation of BlockLimits to bdrv_refresh_limits()Kevin Wolf6-23/+87
This function separates filling the BlockLimits from bdrv_open(), which allows it to call it from other operations which may change the limits (e.g. modifications to the backing file chain or bdrv_reopen) Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: Fix bdrv_commit return valueKevin Wolf1-5/+10
bdrv_commit() could return 0 or 1 on success, depending on whether or not the last sector was allocated in the overlay and whether the overlay format had a .bdrv_make_empty callback. Most callers ignored it, but qemu-img commit would print an error message while the operation actually succeeded. Also clean up the handling of I/O errors to return the real error code instead of -EIO. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24block: update block commit documentation regarding image truncationJeff Cody4-1/+57
This updates the documentation for commiting snapshot images. Specifically, this highlights what happens when the base image is either smaller or larger than the snapshot image being committed. In the case of the base image being smaller, it is resized to the larger size of the snapshot image. In the case of the base image being larger, it is not resized automatically, but once the commit has completed it is safe for the user to truncate the base image. Signed-off-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-24block: resize backing image during active layer commit, if neededJeff Cody1-0/+38
If the top image to commit is the active layer, and also larger than the base image, then an I/O error will likely be returned during block-commit. For instance, if we have a base image with a virtual size 10G, and a active layer image of size 20G, then committing the snapshot via 'block-commit' will likely fail. This will automatically attempt to resize the base image, if the active layer image to be committed is larger. Signed-off-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-24block: resize backing file image during offline commit, if necessaryJeff Cody1-3/+25
Currently, if an image file is logically larger than its backing file, committing it via 'qemu-img commit' will fail. For instance, if we have a base image with a virtual size 10G, and a snapshot image of size 20G, then committing the snapshot offline with 'qemu-img commit' will likely fail. This will automatically attempt to resize the base image, if the snapshot image to be committed is larger. Signed-off-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-24block/curl: Implement the libcurl timer callback interfacePeter Maydell1-11/+70
libcurl versions 7.16.0 and later have a timer callback interface which must be implemented in order for libcurl to make forward progress (it will sometimes rely on being called back on the timeout if there are no file descriptors registered). Implement the callback, and use a QEMU AIO timer to ensure we prod libcurl again when it asks us to. Based on Peter's original patch plus my fix to add curl_multi_timeout_do. Should compile just fine even on older versions of libcurl. I also tried copy-on-read and streaming: $ ./qemu-img create -f qcow2 -o \ backing_file=http://download.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso \ foo.qcow2 1G $ x86_64-softmmu/qemu-system-x86_64 \ -drive if=none,file=foo.qcow2,copy-on-read=on,id=cd \ -device ide-cd,drive=cd --enable-kvm -m 1024 Direct http usage is probably too slow, but with copy-on-read ultimately the image does boot! After some time, streaming gets canceled by an EIO, which needs further investigation. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-24qmp: Allow to take external snapshots on bs graphs node.Benoît Canet4-12/+71
Signed-off-by: Benoit Canet <benoit@irqsave.net> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-24qmp: Allow block_resize to manipulate bs graph nodes.Benoît Canet4-8/+25
Signed-off-by: Benoit Canet <benoit@irqsave.net> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-24block: Create authorizations mechanism for external snapshot and resize.Benoît Canet5-24/+77
Signed-off-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-24qmp: Allow to change password on named block driver states.Benoît Canet6-8/+54
Signed-off-by: Benoit Canet <benoit@irqsave.net> Reviewed-by: Fam Zheng <famz@redhat.com> There was two candidate ways to implement named node manipulation: 1) { 'command': 'block_passwd', 'data': {'*device': 'str', '*node-name': 'str', 'password': 'str'} } 2) { 'command': 'block_passwd', 'data': {'device': 'str', '*device-is-node': 'bool', 'password': 'str'} } Luiz proposed 1 and says 2 was an abuse of the QMP interface and proposed to rewrite the QMP block interface for 2.0. Luiz does not like in 1 the fact that 2 fields are optional but one of them must be specified leading to an abuse of the QMP semantic. Kevin argumented that 2 what a clear abuse of the device field and would not be practical when reading fast some log file because the user would read "device" and think that a device is manipulated when it's in fact a node name. Documentation of 1 make it pretty clear what to do for the user. Kevin argued that all bs are node including devices ones so 2 does not make sense. Kevin also argued that rewriting the QMP block interface would not make disapear the current one. Kevin pushed the argument that making the QAPI generator compatible with the semantic of the operation would need a rewrite that no one has done yet. A vote has been done on the list to elect the version to use and 1 won. For reference the complete thread is: "[Qemu-devel] [PATCH V4 4/7] qmp: Allow to change password on names block driver states." Signed-off-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-24qmp: Add QMP query-named-block-nodes to list the named BlockDriverState nodes.Benoît Canet7-56/+155
Signed-off-by: Benoit Canet <benoit@irqsave.net> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-24block: Allow the user to define "node-name" option both on command line and QMP.Benoît Canet2-0/+37
Signed-off-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Kevin Wolf <kwolf@redhat.com>