Make tcg_gen_callN a static function. Create tcg_gen_call[0-7]
functions for use by helper-gen.h.inc.
Removes a multiplicty of calls to __stack_chk_fail, saving up
to 143kiB of .text space as measured on an x86_64 host.
Old New Less %Change
8888680 8741816 146864 1.65% qemu-system-aarch64
5911832 5856152 55680 0.94% qemu-system-riscv64
5816728 5767512 49216 0.85% qemu-system-mips64
6707832 6659144 48688 0.73% qemu-system-ppc64
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Removes a multiplicity of calls to __assert_fail, saving up
to 360kiB of .text space as measured on an x86_64 host.
Old New Less %Change
9257272 8888680 368592 3.98% qemu-system-aarch64
6100968 5911832 189136 3.10% qemu-system-riscv64
5839112 5707032 132080 2.26% qemu-system-mips
4447608 4341752 105856 2.38% qemu-system-s390x
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In preparation for compiling tcg/ only once, eliminate
the all_helpers array. Instantiate the info structs for
the generic helpers in accel/tcg/, and the structs for
the target-specific helpers in each translate.c.
Since we don't see all of the info structs at startup,
initialize at first use, using g_once_init_* to make
sure we don't race while doing so.
Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This will be required outside of tcg-internal.h soon.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This had been included via tcg-op-common.h via tcg-op.h,
but that is going away. In idef-parser.y, shuffle some
tcg related includes into a more logical order.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This had been included via tcg-op-common.h via tcg-op.h,
but that is going away.
It is needed for inlines within translator.h, so we might as well
do it there and not individually in each translator c file.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Create tcg/tcg-op-common.h, moving everything that does not concern
TARGET_LONG_BITS or TCGv. Adjust tcg/*.c to use the new header
instead of tcg-op.h, in preparation for compiling tcg/ only once.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These two items are the last uses of TARGET_LONG_BITS within tcg.h,
and are more in common with the other "_tl" definitions within that file.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Move a use of TARGET_LONG_BITS out of tcg/tcg.h.
Include the new file only where required.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The symbol is always defined, even if to 0. We wanted to test for
TCG_OVERSIZED_GUEST == 0.
This fixed, the #error is reached while building arm-softmmu, because
TCG_OVERSIZED_GUEST is not true (nor supposed to be true) for arm32
guest on a 32-bit host. But that's ok, because this feature doesn't
apply to arm32. Add an #ifdef for TARGET_AARCH64.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Often, the only thing we need to know about the TCG host
is the register size.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This had been pulled in from exec/cpu_ldst.h, via exec/exec-all.h,
but the include of tcg.h will be removed.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This had been pulled in from tcg/tcg.h, via exec/cpu_ldst.h,
via exec/exec-all.h, but the include of tcg.h will be removed.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This had been pulled in from tcg/tcg.h, via exec/cpu_ldst.h,
via exec/exec-all.h, but the include of tcg.h will be removed.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Disconnect the layout of ArchCPU from TCG compilation.
Pass the relative offset of 'env' and 'neg.tlb.f' as a parameter.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This makes CPUTLBEntry agnostic to the address size of the guest.
When 32-bit addresses are in effect, we can simply read the low
32 bits of the 64-bit field. Similarly when we need to update
the field for setting TLB_NOTDIRTY.
For TCG backends that could in theory be big-endian, but in
practice are not (arm, loongarch, riscv), use QEMU_BUILD_BUG_ON
to document and ensure this is not accidentally missed.
For s390x, which is always big-endian, use HOST_BIG_ENDIAN anyway,
to document the reason for the adjustment.
For sparc64 and ppc64, always perform a 64-bit load, and rely on
the following 32-bit comparison to ignore the high bits.
Rearrange mips and ppc if ladders for clarity.
Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Removes the only use of TARGET_LONG_BITS from tcg.h, which is to be
target independent. Move the symbol to a define in tcg-op.h, which
will continue to be target dependent. Rather than complicate matters
for the use in tb_gen_code(), expand the definition there.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
All uses replaced with TCGContext.addr_type.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
All uses replaced with TCGContext.addr_type.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
All uses replaced with TCGContext.addr_type.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
All uses replaced with TCGContext.addr_type.
Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
It is required for implementing /proc/cpuinfo emulation.
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20230605113950.1169228-4-iii@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
It is required for implementing /proc/cpuinfo emulation.
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20230605113950.1169228-3-iii@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
In qemu-user-s390x, /proc/cpuinfo contains:
processor 0: version = 00, identification = 000000, machine = 8561
processor 1: version = 00, identification = 400000, machine = 8561
The highest nibble is supposed to contain the CPU address, but it's off
by 2 bits. Fix the shift value and provide a symbolic constant for it.
With the fix we get:
processor 0: version = 00, identification = 000000, machine = 8561
processor 1: version = 00, identification = 100000, machine = 8561
Fixes: 076d4d39b6 ("s390x/cpumodel: wire up cpu type + id for TCG")
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20230605113950.1169228-2-iii@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Mechanical change running Coccinelle spatch with content
generated from the qom-cast-macro-clean-cocci-gen.py added
in the previous commit.
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230601093452.38972-3-philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Add a script to generate Coccinelle semantic patch
removing all pointless QOM cast macro uses.
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230601093452.38972-2-philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Booting a Linux kernel with the malta machine is currently broken
on big endian hosts. The cpu_to_gt32 macro wants to byteswap a value
for little endian targets only, but uses the wrong way to do this:
cpu_to_[lb]e32 works the other way round on big endian hosts! Fix
it by using the same ways on both, big and little endian hosts.
Fixes: 0c8427baf0 ("hw/mips/malta: Use bootloader helper to set BAR registers")
Cc: qemu-stable@nongnu.org
Message-Id: <20230330152613.232082-1-thuth@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Python should have been removed in this commit:
94b8b146df
Signed-off-by: Camilla Conte <cconte@redhat.com>
Message-Id: <20230531150824.32349-2-cconte@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
- Fix padding of unaligned vectored requests to match the host alignment
for vectors with 1023 or 1024 buffers
- Refactor and fix bugs in parallels's image check functionality
- Add an option to the qcow2 driver to retain (qcow2-level) allocations
on discard requests from the guest (while still forwarding the discard
to the lower level and marking the range as zero)
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Merge tag 'pull-block-2023-06-05' of https://gitlab.com/hreitz/qemu into staging
Block patches
- Fix padding of unaligned vectored requests to match the host alignment
for vectors with 1023 or 1024 buffers
- Refactor and fix bugs in parallels's image check functionality
- Add an option to the qcow2 driver to retain (qcow2-level) allocations
on discard requests from the guest (while still forwarding the discard
to the lower level and marking the range as zero)
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# gpg: Signature made Mon 05 Jun 2023 08:37:34 AM PDT
# gpg: using RSA key CB62D7A0EE3829E45F004D34A1FA40D098019CDF
# gpg: issuer "hreitz@redhat.com"
# gpg: Good signature from "Hanna Reitz <hreitz@redhat.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: CB62 D7A0 EE38 29E4 5F00 4D34 A1FA 40D0 9801 9CDF
* tag 'pull-block-2023-06-05' of https://gitlab.com/hreitz/qemu:
qcow2: add discard-no-unref option
parallels: Incorrect condition in out-of-image check
parallels: Replace qemu_co_mutex_lock by WITH_QEMU_LOCK_GUARD
parallels: Move statistic collection to a separate function
parallels: Move check of leaks to a separate function
parallels: Fix statistics calculation
parallels: Move check of cluster outside image to a separate function
parallels: Move check of unclean image to a separate function
parallels: Use generic infrastructure for BAT writing in parallels_co_check()
parallels: create parallels_set_bat_entry_helper() to assign BAT value
parallels: Fix image_end_offset and data_end after out-of-image check
parallels: Fix high_off calculation in parallels_co_check()
parallels: Out of image offset in BAT leads to image inflation
iotests/iov-padding: New test
util/iov: Remove qemu_iovec_init_extended()
block: Collapse padded I/O vecs exceeding IOV_MAX
util/iov: Make qiov_slice() public
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
When we for example have a sparse qcow2 image and discard: unmap is enabled,
there can be a lot of fragmentation in the image after some time. Especially on VM's
that do a lot of writes/deletes.
This causes the qcow2 image to grow even over 110% of its virtual size,
because the free gaps in the image get too small to allocate new
continuous clusters. So it allocates new space at the end of the image.
Disabling discard is not an option, as discard is needed to keep the
incremental backup size as low as possible. Without discard, the
incremental backups would become large, as qemu thinks it's just dirty
blocks but it doesn't know the blocks are unneeded.
So we need to avoid fragmentation but also 'empty' the unneeded blocks in
the image to have a small incremental backup.
In addition, we also want to send the discards further down the stack, so
the underlying blocks are still discarded.
Therefor we introduce a new qcow2 option "discard-no-unref".
When setting this option to true, discards will no longer have the qcow2
driver relinquish cluster allocations. Other than that, the request is
handled as normal: All clusters in range are marked as zero, and, if
pass-discard-request is true, it is passed further down the stack.
The only difference is that the now-zero clusters are preallocated
instead of being unallocated.
This will avoid fragmentation on the qcow2 image.
Fixes: https://gitlab.com/qemu-project/qemu/-/issues/1621
Signed-off-by: Jean-Louis Dupond <jean-louis@dupond.be>
Message-Id: <20230605084523.34134-2-jean-louis@dupond.be>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
All the offsets in the BAT must be lower than the file size.
Fix the check condition for correct check.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Message-Id: <20230424093147.197643-13-alexander.ivanov@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Replace the way we use mutex in parallels_co_check() for simplier
and less error prone code.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Message-Id: <20230424093147.197643-12-alexander.ivanov@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
We will add more and more checks so we need a better code structure
in parallels_co_check. Let each check performs in a separate loop
in a separate helper.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20230424093147.197643-11-alexander.ivanov@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
We will add more and more checks so we need a better code structure
in parallels_co_check. Let each check performs in a separate loop
in a separate helper.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Message-Id: <20230424093147.197643-10-alexander.ivanov@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Exclude out-of-image clusters from allocated and fragmented clusters
calculation.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Message-Id: <20230424093147.197643-9-alexander.ivanov@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
We will add more and more checks so we need a better code structure in
parallels_co_check. Let each check performs in a separate loop in a
separate helper.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Message-Id: <20230424093147.197643-8-alexander.ivanov@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
We will add more and more checks so we need a better code structure
in parallels_co_check. Let each check performs in a separate loop
in a separate helper.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20230424093147.197643-7-alexander.ivanov@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
BAT is written in the context of conventional operations over the image
inside bdrv_co_flush() when it calls parallels_co_flush_to_os() callback.
Thus we should not modify BAT array directly, but call
parallels_set_bat_entry() helper and bdrv_co_flush() further on. After
that there is no need to manually write BAT and track its modification.
This makes code more generic and allows to split parallels_set_bat_entry()
for independent pieces.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Message-Id: <20230424093147.197643-6-alexander.ivanov@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
This helper will be reused in next patches during parallels_co_check
rework to simplify its code.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20230424093147.197643-5-alexander.ivanov@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Set data_end to the end of the last cluster inside the image. In such a
way we can be sure that corrupted offsets in the BAT can't affect on the
image size. If there are no allocated clusters set image_end_offset by
data_end.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Message-Id: <20230424093147.197643-4-alexander.ivanov@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Don't let high_off be more than the file size even if we don't fix the
image.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20230424093147.197643-3-alexander.ivanov@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
data_end field in BDRVParallelsState is set to the biggest offset present
in BAT. If this offset is outside of the image, any further write will
create the cluster at this offset and/or the image will be truncated to
this offset on close. This is definitely not correct.
Raise an error in parallels_open() if data_end points outside the image
and it is not a check (let the check to repaire the image). Set data_end
to the end of the cluster with the last correct offset.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Message-Id: <20230424093147.197643-2-alexander.ivanov@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Test that even vectored IO requests with 1024 vector elements that are
not aligned to the device's request alignment will succeed.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230411173418.19549-5-hreitz@redhat.com>
bdrv_pad_request() was the main user of qemu_iovec_init_extended().
HEAD^ has removed that use, so we can remove qemu_iovec_init_extended()
now.
The only remaining user is qemu_iovec_init_slice(), which can easily
inline the small part it really needs.
Note that qemu_iovec_init_extended() offered a memcpy() optimization to
initialize the new I/O vector. qemu_iovec_concat_iov(), which is used
to replace its functionality, does not, but calls qemu_iovec_add() for
every single element. If we decide this optimization was important, we
will need to re-implement it in qemu_iovec_concat_iov(), which might
also benefit its pre-existing users.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230411173418.19549-4-hreitz@redhat.com>
When processing vectored guest requests that are not aligned to the
storage request alignment, we pad them by adding head and/or tail
buffers for a read-modify-write cycle.
The guest can submit I/O vectors up to IOV_MAX (1024) in length, but
with this padding, the vector can exceed that limit. As of
4c002cef0e ("util/iov: make
qemu_iovec_init_extended() honest"), we refuse to pad vectors beyond the
limit, instead returning an error to the guest.
To the guest, this appears as a random I/O error. We should not return
an I/O error to the guest when it issued a perfectly valid request.
Before 4c002cef0e, we just made the vector
longer than IOV_MAX, which generally seems to work (because the guest
assumes a smaller alignment than we really have, file-posix's
raw_co_prw() will generally see bdrv_qiov_is_aligned() return false, and
so emulate the request, so that the IOV_MAX does not matter). However,
that does not seem exactly great.
I see two ways to fix this problem:
1. We split such long requests into two requests.
2. We join some elements of the vector into new buffers to make it
shorter.
I am wary of (1), because it seems like it may have unintended side
effects.
(2) on the other hand seems relatively simple to implement, with
hopefully few side effects, so this patch does that.
To do this, the use of qemu_iovec_init_extended() in bdrv_pad_request()
is effectively replaced by the new function bdrv_create_padded_qiov(),
which not only wraps the request IOV with padding head/tail, but also
ensures that the resulting vector will not have more than IOV_MAX
elements. Putting that functionality into qemu_iovec_init_extended() is
infeasible because it requires allocating a bounce buffer; doing so
would require many more parameters (buffer alignment, how to initialize
the buffer, and out parameters like the buffer, its length, and the
original elements), which is not reasonable.
Conversely, it is not difficult to move qemu_iovec_init_extended()'s
functionality into bdrv_create_padded_qiov() by using public
qemu_iovec_* functions, so that is what this patch does.
Because bdrv_pad_request() was the only "serious" user of
qemu_iovec_init_extended(), the next patch will remove the latter
function, so the functionality is not implemented twice.
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2141964
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230411173418.19549-3-hreitz@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
We want to inline qemu_iovec_init_extended() in block/io.c for padding
requests, and having access to qiov_slice() is useful for this. As a
public function, it is renamed to qemu_iovec_slice().
(We will need to count the number of I/O vector elements of a slice
there, and then later process this slice. Without qiov_slice(), we
would need to call qemu_iovec_subvec_niov(), and all further
IOV-processing functions may need to skip prefixing elements to
accomodate for a qiov_offset. Because qemu_iovec_subvec_niov()
internally calls qiov_slice(), we can just have the block/io.c code call
qiov_slice() itself, thus get the number of elements, and also create an
iovec array with the superfluous prefixing elements stripped, so the
following processing functions no longer need to skip them.)
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230411173418.19549-2-hreitz@redhat.com>
The ipmi-bt-test uses "-device ipmi-bmc-extern", thus it should
only be run if this device has been enabled in the configuration.
Message-Id: <20230524081024.1619273-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
