Invented by Anthony. Maintained through my qom-next tree lately.
Cc: Anthony Liguori <aliguori@amazon.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Using error_is_set(ERRP) to find out whether a function failed is
either wrong, fragile, or unnecessarily opaque. It's wrong when ERRP
may be null, because errors go undetected when it is. It's fragile
when proving ERRP non-null involves a non-local argument. Else, it's
unnecessarily opaque (see commit 84d18f0).
I guess the error_is_set(errp) in the DeviceClass realize() methods
are merely fragile right now, because I can't find a call chain that
passes a null errp argument.
Make the code more robust and more obviously correct: receive the
error in a local variable, then propagate it through the parameter.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Using error_is_set(ERRP) to find out whether a function failed is
either wrong, fragile, or unnecessarily opaque. It's wrong when ERRP
may be null, because errors go undetected when it is. It's fragile
when proving ERRP non-null involves a non-local argument. Else, it's
unnecessarily opaque (see commit 84d18f0).
I guess the error_is_set(errp) in the ObjectProperty set() methods are
merely fragile right now, because I can't find a call chain that
passes a null errp argument.
Make the code more robust and more obviously correct: receive the
error in a local variable, then propagate it through the parameter.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
No need to go through qemu_machine field. Use
MachineClass fields directly.
Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
This minimizes QEMUMachine usage, as part of machine QOM-ification.
Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
QEMUMachine's fields are already in MachineClass. We can safely
make the switch because we copy them in machine_class_init() and
spapr_machine_class_init().
Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
In order to eliminate the QEMUMachine indirection,
add its fields directly to MachineClass.
Do not yet remove qemu_machine field because it is
still in use by sPAPR.
Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com>
[AF: Copied fields for sPAPR, too]
Signed-off-by: Andreas Färber <afaerber@suse.de>
This field shouldn't be used any more since we
adopted the QOM way of iterating over the types.
The commit that obsoleted it is:
commit 261747f176
vl: Use MachineClass instead of global QEMUMachine list
The machine registration flow is refactored to use the QOM functionality.
Instead of linking the machines into a list, each machine has a type
and the types can be traversed in the QOM way.
Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
QEMU crashed when I try to list device parameters and the driver name is
actually an available bus name.
# qemu -device virtio-pci-bus,?
# qemu -device virtio-bus,?
# qemu -device virtio-serial-bus,?
qdev-monitor.c:212:qdev_device_help: Object 0x7fd932f50620 is not an
instance of type device
Aborted (core dumped)
We can also reproduce this bug by adding device from monitor, so it's
worth to fix the crash.
(qemu) device_add virtio-serial-bus
qdev-monitor.c:491:qdev_device_add: Object 0x7f5e89530920 is not an
instance of type device
Aborted (core dumped)
Cc: qemu-stable@nongnu.org
Signed-off-by: Amos Kong <akong@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
* implement XScale cache lockdown cp15 ops
* fix v7M CPUID base register
* implement WFE and YIELD as yields for A64
* fix A64 "BLR LR"
* support Cortex-A57 in virt machine model
* a few other minor AArch64 bugfixes
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Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20140501' into staging
target-arm queue:
* implement XScale cache lockdown cp15 ops
* fix v7M CPUID base register
* implement WFE and YIELD as yields for A64
* fix A64 "BLR LR"
* support Cortex-A57 in virt machine model
* a few other minor AArch64 bugfixes
# gpg: Signature made Thu 01 May 2014 15:42:17 BST using RSA key ID 14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
* remotes/pmaydell/tags/pull-target-arm-20140501:
hw/arm/virt: Add support for Cortex-A57
hw/arm/virt: Put GIC register banks on 64K boundaries
hw/arm/virt: Create the GIC ourselves rather than (ab)using a15mpcore_priv
target-arm: Correct a comment refering to EL0
target-arm: A64: Fix a typo when declaring TLBI ops
target-arm: A64: Handle blr lr
target-arm: Make vbar_write 64bit friendly on 32bit hosts
target-arm: implement WFE/YIELD as a yield for AArch64
armv7m_nvic: fix CPUID Base Register
target-arm: Implement XScale cache lockdown operations as NOPs
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block patches
# gpg: Signature made Wed 30 Apr 2014 19:19:32 BST using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
* remotes/kevin/tags/for-upstream: (31 commits)
curl: Fix hang reading from slow connections
curl: Ensure all informationals are checked for completion
curl: Eliminate unnecessary use of curl_multi_socket_all
curl: Remove unnecessary explicit calls to internal event handler
curl: Remove erroneous sleep waiting for curl completion
curl: Fix return from curl_read_cb with invalid state
curl: Remove unnecessary use of goto
curl: Fix long line
block/vdi: Error out immediately in vdi_create()
block/bochs: Fix error handling for seek_to_sector()
qcow2: Check min_size in qcow2_grow_l1_table()
qcow2: Catch bdrv_getlength() error
block: Use correct width in format strings
qcow2: Avoid overflow in alloc_clusters_noref()
block: Use error_abort in bdrv_image_info_specific_dump()
block: Fix open_flags in bdrv_reopen()
Revert "block: another bdrv_append fix"
block: Unlink temporary files in raw-posix/win32
block: Remove BDRV_O_COPY_ON_READ for bs->file
block: Create bdrv_backing_flags()
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
s390x and ppc users to use them.
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Merge remote-tracking branch 'remotes/cohuck/tags/kvm_cap_helpers' into staging
Add helpers for enabling kvm capabilities and convert the existing
s390x and ppc users to use them.
# gpg: Signature made Wed 30 Apr 2014 14:48:45 BST using RSA key ID C6F02FAF
# gpg: Can't check signature: public key not found
* remotes/cohuck/tags/kvm_cap_helpers:
ppc: use kvm_vcpu_enable_cap()
s390x: use kvm_vcpu_enable_cap()
kvm: add kvm_{vm,vcpu}_enable_cap
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
For an AArch64 CPU which supports 64K pages, having the GIC
register banks at 4K offsets is potentially awkward. Move
them out to being at 64K offsets. (This is harmless for
AArch32 CPUs and for AArch64 CPUs with 4K pages, so it is simpler
to use the same offsets everywhere than to try to use 64K offsets
only for AArch64 host CPUs.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1398362083-17737-3-git-send-email-peter.maydell@linaro.org
Rather than having the virt machine model create an a15mpcore_priv
device regardless of the actual CPU type in order to instantiate the GIC,
move to having the machine model create the GIC directly. This
corresponds to a system which uses a standalone GIC (eg the GIC-400)
rather than the one built in to the CPU core.
The primary motivation for this is to support the Cortex-A57,
which for a KVM configuration will use a GICv2, which is not
built into the CPU.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1398362083-17737-2-git-send-email-peter.maydell@linaro.org
Harmless typo as opc1 defaults to zero and opc2 gets
re-declared to its correct value.
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1398926097-28097-4-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
For linked branches, updates to the link register happen
conceptually after the read of the branch target register.
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Cc: qemu-stable@nongnu.org
Message-id: 1398926097-28097-3-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1398926097-28097-2-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Like was done for AArch32 for WFE, implement both WFE and YIELD as a
yield operation. This speeds up multi-core system emulation.
Signed-off-by: Rob Herring <rob.herring@linaro.org>
Message-id: 1397588401-20366-1-git-send-email-robherring2@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
cp15.c0_cpuid is never initialized for ARMv7-M; take the value directly
from cpu->midr instead.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Message-id: 1398036308-32166-1-git-send-email-rabin@rab.in
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
XScale defines some implementation-specific coprocessor registers
for doing cache lockdown operations. Since QEMU doesn't model a
cache no proper implementation is possible, but NOP out the
registers so that guest code like u-boot that tries to use them
doesn't crash.
Reported-by: <prqek@centrum.cz>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When receiving a new aio read request, we first look for an existing
transaction whose range will cover the read request by the time it
completes. However, we weren't checking that the existing transaction
was still active. If it had timed out, we were adding the request to a
transaction which would never complete and had already been cancelled,
resulting in a hang.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
According to the documentation, the correct way to ensure all
informationals have been returned by curl_multi_info_read is to loop
until it returns NULL.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
curl_multi_socket_all is a deprecated catch-all which checks for
activities on all open curl sockets. We have enough information from
the event loop to check only the sockets with activity. This change
removes use of curl_multi_socket_all in favour of
curl_multi_socket_action called with the relevant handle.
At the same time, it also ensures that the driver only checks for
completion of read operations after reading from a socket, rather than
both reading and writing.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Remove calls to curl_multi_do where the relevant handles are already
registered to the event loop.
Ensure that we kick off socket handling with CURL_SOCKET_TIMEOUT after
adding a new handle.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The driver will not start more than a fixed number of curl sessions.
If it needs more, it must wait for the completion of an existing one.
The driver was sleeping, which will prevent the main loop from
running, and therefore the event it's waiting on. It was also directly
calling its internal handler rather than waiting on existing
registered handlers to be called from the main loop.
This change causes it simply to wait for a period of time whilst
allowing the main loop to execute.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
A curl write callback is supposed to return the number of bytes it
handled. curl_read_cb would have erroneously reported it had handled
all bytes in the event that the internal curl state was invalid.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This isn't any of the usually acceptable uses of goto.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently, if an error occurs during the part of vdi_create() which
actually writes the image, the function stores -errno, but continues
anyway.
Instead of trying to write data which (if it can be written at all) does
not make any sense without the operations before succeeding (e.g.,
writing the image header), just error out immediately.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently, seek_to_sector() returns -1 both for errors and unallocated
sectors, resulting in silent errors. As 0 is an invalid offset of data
clusters (bitmap_offset is greater than 0 because s->data_offset is
greater than 0), just return 0 for unallocated sectors and -errno in
case of error. This should then be propagated by bochs_read(), the sole
user of seek_to_sector().
That function also has a case of "return -1 in case of error", which is
fixed by this patch as well.
bochs_read() is called by bochs_co_read() which passes the return value
through, therefore it is indeed correct for bochs_read() to return
-errno.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
First, new_l1_size is an int64_t, whereas min_size is a uint64_t.
Therefore, during the loop which adjusts new_l1_size until it equals or
exceeds min_size, new_l1_size might overflow and become negative. The
comparison in the loop condition however will take it as an unsigned
value (because min_size is unsigned) and therefore recognize it as
exceeding min_size. Therefore, the loop is left with a negative
new_l1_size, which is not correct. This could be fixed by making
new_l1_size uint64_t.
On the other hand, however, by doing this, the while loop may take
forever. If min_size is e.g. UINT64_MAX, it will take new_l1_size
probably multiple overflows to reach the exact same value (if it reaches
it at all). Then, right after the loop, new_l1_size will be recognized
as being too big anyway.
Both problems require a ridiculously high min_size value, which is very
unlikely to occur; but both problems are also simply avoided by checking
whether min_size is sane before calculating new_l1_size (which should
still be checked separately, though).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The call to bdrv_getlength() from qcow2_check_refcounts() may result in
an error. Check this and abort if necessary.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Instead of blindly relying on a normal integer having a width of 32 bits
(which is a pretty good assumption, but we should not rely on it if
there is no need), use the correct format string macros.
This does not touch DEBUG output.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
alloc_clusters_noref() stores the cluster index in a uint64_t. However,
offsets are often represented as int64_t (as for example the return
value of alloc_clusters_noref() itself demonstrates). Therefore, we
should make sure all offsets in the allocated range of clusters are
representable using int64_t without overflows.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Convert existing users of KVM_ENABLE_CAP to new helper.
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Make kvm_s390_enable_css_support() use new interface.
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Provide helper functions for enabling capabilities (on a vcpu and on a vm).
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Currently, bdrv_image_info_specific_dump() uses an error variable for
visit_type_ImageInfoSpecific, but ignores the result. As this function
is used here with an output visitor to transform the ImageInfoSpecific
object to a generic QDict, an error should actually be impossible. It is
however better to assert that this is indeed the case. This is done by
this patch using error_abort instead of an unused local Error variable.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reported-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Use the same function as bdrv_open() for determining what the right
flags for bs->file are. Without doing this, a reopen means that
bs->file loses BDRV_O_CACHE_WB or BDRV_O_UNMAP if bs doesn't have it as
well.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
This reverts commit 3a389e7926. The commit
was wrong and what it tried to fix just works today without any change.
What the commit tried to fix:
When creating live snapshots, the new image file is opened with
BDRV_O_NO_BACKING because the whole backing chain is already opened.
It is then appended to the chain using bdrv_append(). The result of
this was that the image had a backing file, but BDRV_O_NO_BACKING
was still set. This is obviously inconsistent.
There used to be some places in qemu that closed and image and then
opened it again, with its old flags (a bdrv_open()/close() sequence
involves reopening the whole backing file chain, too). In this case
the BDRV_O_NO_BACKING flag meant that the backing chain wasn't
reopened and only the top layer was left.
(Most, but not all of these places are replaced by bdrv_reopen()
today, which doesn't touch the backing files at all.)
Other places that looked at bs->open_flags weren't interested in
BDRV_O_NO_BACKING, so no breakage there.
What it actually did:
The commit moved the BDRV_O_NO_BACKING away to the backing file.
Because the bdrv_open()/close() sequences only looked at the flags
of the top level BlockDriverState and used it for the whole chain,
the flag didn't hurt there any more. Obviously, it is still
inconsistent because the backing file may have another backing file,
but without practical impact.
At the same time, it swapped all other flags. This is practically
irrelevant as long as live snapshots only allow opening the new
layer with the same flags as the old top layer. It still doesn't
make any sense, and it is a time bomb that explodes as soon as the
flags can differ.
bdrv_append_temp_snapshot() is such a case: It adds the new flag
BDRV_O_TEMPORARY for the temporary snapshot. The swapping of commit
3a389e79 results in the following nonsensical configuration:
bs->open_flags: BDRV_O_TEMPORARY cleared
bs->file->open_flags: BDRV_O_TEMPORARY set
bs->backing_hd->open_flags: BDRV_O_TEMPORARY set
bs->backing_hd->file->open_flags: BDRV_O_TEMPORARY cleared
We're still lucky because the format layer ignores the flag and the
protocol layer happens to get the right value, but sooner or later
this is bound to go wrong...
What the right fix would have been:
Simply clear the BDRV_O_NO_BACKING flag when the BlockDriverState is
appended to an existing backing file chain, because now it does have
a backing file.
Commit 4ddc07ca already implemented this silently in bdrv_append(),
so we don't have to come up with a new fix.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Instead of having unlink() calls in the generic block layer, where we
aren't even guarateed to have a file name, move them to those block
drivers that are actually used and that always have a filename. Gets us
rid of some #ifdefs as well.
The patch also converts bs->is_temporary to a new BDRV_O_TEMPORARY open
flag so that it is inherited in the protocol layer and the raw-posix and
raw-win32 drivers can unlink the file.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Copy on Read makes sense on the format level where backing files are
implemented, but it's not required on the protocol level. While it
shouldn't actively break anything to have COR enabled on both layers,
needless serialisation and allocation checks may impact performance.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Andreas Färber
Markus Armbruster
Marcel Apfelbaum
Amos Kong
Peter Maydell
Edgar E. Iglesias
Rob Herring
Rabin Vincent
Matthew Booth
Max Reitz
Cornelia Huck
Kevin Wolf