Linux limits the size of iovecs to 1024 (UIO_MAXIOV in the kernel
sources, IOV_MAX in POSIX). Because of this, on some host adapters
requests with many iovecs are rejected with -EINVAL by the
io_submit() or readv()/writev() system calls.
In fact, the same limit applies to SG_IO as well. To fix both the
EINVAL and the possible performance issues from using fewer iovecs
than allowed by Linux (some HBAs have max_segments as low as 128),
introduce a separate entry in BlockLimits to hold the max_segments
value from sysfs. This new limit is used only for SG_IO and clamped
to bs->bl.max_iov anyway, just like max_hw_transfer is clamped to
bs->bl.max_transfer.
Reported-by: Halil Pasic <pasic@linux.ibm.com>
Cc: Hanna Reitz <hreitz@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-block@nongnu.org
Cc: qemu-stable@nongnu.org
Fixes: 18473467d5 ("file-posix: try BLKSECTGET on block devices too, do not round to power of 2", 2021-06-25)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210923130436.1187591-1-pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
For block host devices, I/O can happen through either the kernel file
descriptor I/O system calls (preadv/pwritev, io_submit, io_uring)
or the SCSI passthrough ioctl SG_IO.
In the latter case, the size of each transfer can be limited by the
HBA, while for file descriptor I/O the kernel is able to split and
merge I/O in smaller pieces as needed. Applying the HBA limits to
file descriptor I/O results in more system calls and suboptimal
performance, so this patch splits the max_transfer limit in two:
max_transfer remains valid and is used in general, while max_hw_transfer
is limited to the maximum hardware size. max_hw_transfer can then be
included by the scsi-generic driver in the block limits page, to ensure
that the stricter hardware limit is used.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
I/O to a disk via read/write is not limited by the number of segments allowed
by the host adapter; the kernel can split requests if needed, and the limit
imposed by the host adapter can be very low (256k or so) to avoid that SG_IO
returns EINVAL if memory is heavily fragmented.
Since this value is only interesting for SG_IO-based I/O, do not include
it in the max_transfer and only take it into account when patching the
block limits VPD page in the scsi-generic device.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
When the device doesn't support the VPD block limits page, we emulate it even
for SCSI passthrough.
As a part of the emulation we need to add it to the 'Supported VPD Pages'
The code that does this adds it to the page, but it doesn't increase the length
of the data to be copied to the guest, thus the guest never sees the VPD block
limits page as supported.
Bump the transfer size by 1 in this case.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20201217165612.942849-6-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Some SCSI drivers like virtio have an internal mapping for the
host_status. This patch moves the host_status translation into
the SCSI drivers to allow those drivers to set up the correct
values.
Signed-off-by: Hannes Reinecke <hare@suse.de>.
[Added default handling to avoid touching all drivers. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently sg_io_sense_from_errno() converts the two input parameters
'errno' and 'io_hdr' into sense code and SCSI status. Having
split the function off into scsi_sense_from_errno() and
scsi_sense_from_host_status(), both of which are available generically,
we now inline the logic in the callers so that scsi-disk and
scsi-generic will be able to pass host_status to the HBA.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Message-Id: <20201116184041.60465-7-hare@suse.de>
[Put together from "scsi-disk: Add sg_io callback to evaluate status"
and what remains of "scsi: split sg_io_sense_from_errno() in two functions",
with many other fixes. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If a READ CAPACITY command would fail, for example s->qdev.blocksize would be
set to zero and cause a division by zero on the next use.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
'enospc' is the default for -drive, but qemu allows user to set
drive option werror. If werror of scsi-generic is set to 'report'
by user, qemu will not allow vm to start.
This patch allow user to set werror as 'report' for scsi-generic.
Signed-off-by: Zihao Chang <changzihao1@huawei.com>
Reviewed-by: Fam Zheng <fam@euphon.net>
Message-Id: <20201103061240.1364-1-changzihao1@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add tracepoints for SG_IO commands to allow for debugging
of SG_IO commands.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Message-Id: <20201116183114.55703-4-hare@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The current code sets an infinite timeout on SG_IO requests,
causing the guest to stall if the host experiences a frame
loss.
This patch adds an 'io_timeout' parameter for SCSIDevice to
make the SG_IO timeout configurable, and also shortens the
default timeout to 30 seconds to avoid infinite stalls.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Message-Id: <20201116183114.55703-3-hare@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, blk_is_read_only() tells whether a given BlockBackend can
only be used in read-only mode because its root node is read-only. Some
callers actually try to answer a slightly different question: Is the
BlockBackend configured to be writable, by taking write permissions on
the root node?
This can differ, for example, for CD-ROM devices which don't take write
permissions, but may be backed by a writable image file. scsi-cd allows
write requests to the drive if blk_is_read_only() returns false.
However, the write request will immediately run into an assertion
failure because the write permission is missing.
This patch introduces separate functions for both questions.
blk_supports_write_perm() answers the question whether the block
node/image file can support writable devices, whereas blk_is_writable()
tells whether the BlockBackend is currently configured to be writable.
All calls of blk_is_read_only() are converted to one of the two new
functions.
Fixes: https://bugs.launchpad.net/bugs/1906693
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210118123448.307825-2-kwolf@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Move the property types and property macros implemented in
qdev-properties-system.c to a new qdev-properties-system.h
header.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20201211220529.2290218-16-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Several important steps during device scan depend on SCSI type of the
device. For example, max_transfer property is only determined and
assigned if the device has the type of TYPE_DISK.
Host-managed ZBC disks retain most of the properties of regular SCSI
drives, but they have their own SCSI device type, 0x14. This prevents
the proper assignment of max_transfer property for HM-zoned devices in
scsi-generic driver leading to I/O errors if the maximum i/o size
calculated at the guest exceeds the host value.
To fix this, define TYPE_ZBC to have the standard value from SCSI ZBC
standard spec. Several scan steps that were previously done only for
TYPE_DISK devices, are now performed for the SCSI devices having
TYPE_ZBC too.
Reported-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Message-Id: <20200811225122.17342-3-dmitry.fomichev@wdc.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In my "build everything" tree, changing hw/qdev-properties.h triggers
a recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).
Many places including hw/qdev-properties.h (directly or via hw/qdev.h)
actually need only hw/qdev-core.h. Include hw/qdev-core.h there
instead.
hw/qdev.h is actually pointless: all it does is include hw/qdev-core.h
and hw/qdev-properties.h, which in turn includes hw/qdev-core.h.
Replace the remaining uses of hw/qdev.h by hw/qdev-properties.h.
While there, delete a few superfluous inclusions of hw/qdev-core.h.
Touching hw/qdev-properties.h now recompiles some 1200 objects.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Daniel P. Berrangé" <berrange@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20190812052359.30071-22-armbru@redhat.com>
In my "build everything" tree, changing migration/qemu-file-types.h
triggers a recompile of some 2600 out of 6600 objects (not counting
tests and objects that don't depend on qemu/osdep.h).
The culprit is again hw/hw.h, which supposedly includes it for
convenience.
Include migration/qemu-file-types.h only where it's needed. Touching
it now recompiles less than 200 objects.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-10-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
When READ CAPACITY command completes, scsi_read_complete() function
snoops the command result and updates SCSIDevice members blocksize and
max_lba . However, this update is executed even when READ CAPACITY
command indicates an error in sense data. This causes unexpected
blocksize update with zero value for SCSI devices without
READ CAPACITY(10) command support and eventually results in a divide
by zero. An emulated device by TCMU-runner is an example of a device
that doesn't support READ CAPACITY(10) command.
To avoid the unexpected update, add sense key check in
scsi_read_complete() function. The function already checks the sense key
for VPD Block Limits emulation. Do the scsi_parse_sense_buf() call for
all requests rather than just for VPD Block Limits emulation, so that
blocksize and max_lba are only updated if READ CAPACITY returns zero
sense key.
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
[Extend the check to all requests, not just READ CAPACITY]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-3-armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Whenever the allocation length of a SCSI request is shorter than the size of the
VPD page list, page_idx is used blindly to index into r->buf. Even though
the stores in the insertion sort are protected against overflows, the same is not
true of the reads and the final store of 0xb0.
This basically does the same thing as commit 57dbb58d80 ("scsi-generic: avoid
out-of-bounds access to VPD page list", 2018-11-06), except that here the
allocation length can be chosen by the guest. Note that according to the SCSI
standard, the contents of the PAGE LENGTH field are not altered based
on the allocation length.
The code was introduced by commit 6c219fc8a1 ("scsi-generic: keep VPD
page list sorted", 2018-11-06) but the overflow was already possible before.
Reported-by: Kevin Wolf <kwolf@redhat.com>
Fixes: a71c775b24
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pass other sense, such as UNIT_ATTENTION or BUSY, directly to the
guest.
Reported-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Emulation of the block limits VPD page called back into scsi-disk.c,
which however expected the request to be for a SCSIDiskState and
accessed a scsi-generic device outside the bounds of its struct
(namely to retrieve s->max_unmap_size and s->max_io_size).
To avoid this, move the emulation code to a separate function that
takes a new SCSIBlockLimits struct and marshals it into the VPD
response format.
Reported-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A device can report an excessive number of VPD pages when asked for a
list; this can cause an out-of-bounds access to buf in
scsi_generic_set_vpd_bl_emulation. It should not happen, but
it is technically not incorrect so handle it: do not check any byte
past the allocation length that was sent to the INQUIRY command.
Reported-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Block limits emulation is just placing 0xb0 as the final byte of the
VPD pages list. However, VPD page numbers must be sorted, so change
that to an in-place insert. Since I couldn't find any disk that triggered
the loop more than once, this was tested by adding manually 0xb1
at the end of the list and checking that 0xb0 was added before.
Reported-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The VPD Block Limits Inquiry page is optional, allowing SCSI devices
to not implement it. This is the case for devices like the MegaRAID
SAS 9361-8i and Microsemi PM8069.
In case of SCSI passthrough, the response of this request is used by
the QEMU SCSI layer to set the max_io_sectors that the guest
device will support, based on the value of the max_sectors_kb that
the device has set in the host at that time. Without this response,
the guest kernel is free to assume any value of max_io_sectors
for the SCSI device. If this value is greater than the value from
the host, SCSI Sense errors will occur because the guest will send
read/write requests that are larger than the underlying host device
is configured to support. An example of this behavior can be seen
in [1].
A workaround is to set the max_sectors_kb host value back in the guest
kernel (a process that can be automated using rc.local startup scripts
and the like), but this has several drawbacks:
- it can be troublesome if the guest has many passthrough devices that
needs this tuning;
- if a change in max_sectors_kb is made in the host side, manual change
in the guests will also be required;
- during an OS install it is difficult, and sometimes not possible, to
go to a terminal and change the max_sectors_kb prior to the installation.
This means that the disk can't be used during the install process. The
easiest alternative here is to roll back to scsi-hd, install the guest
and then go back to SCSI passthrough when the installation is done and
max_sectors_kb can be set.
An easier way would be to QEMU handle the absence of the Block Limits
VPD device response, setting max_io_sectors accordingly and allowing
the guest to use the device without the hassle.
This patch adds emulation of the Block Limits VPD response for
SCSI passthrough devices of type TYPE_DISK that doesn't support
it. The following changes were made:
- scsi_handle_inquiry_reply will now check the available VPD
pages from the Inquiry EVPD reply. In case the device does not
- a new function called scsi_generic_set_vpd_bl_emulation,
that is called during device realize, was created to set a
new flag 'needs_vpd_bl_emulation' of the device. This function
retrieves the Inquiry EVPD response of the device to check for
VPD BL support.
- scsi_handle_inquiry_reply will now check the available VPD
pages from the Inquiry EVPD reply in case the device needs
VPD BL emulation, adding the Block Limits page (0xb0) to
the list. This will make the guest kernel aware of the
support that we're now providing by emulation.
- a new function scsi_emulate_block_limits creates the
emulated Block Limits response. This function is called
inside scsi_read_complete in case the device requires
Block Limits VPD emulation and we detected a SCSI Sense
error in the VPD Block Limits reply that was issued
from the guest kernel to the device. This error is
expected: we're reporting support from our side, but
the device isn't aware of it.
With this patch, the guest now queries the Block Limits
page during the device configuration because it is being
advertised in the Supported Pages response. It will either
receive the Block Limits page from the hardware, if it supports
it, or will receive an emulated response from QEMU. At any rate,
the guest now has the information to set the max_sectors_kb
parameter accordingly, sparing the user of SCSI sense errors
that would happen without the emulated response and in the
absence of Block Limits support from the hardware.
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1566195
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1566195
Reported-by: Dac Nguyen <dacng@us.ibm.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20180627172432.11120-4-danielhb413@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
For the VPD Block Limits emulation with SCSI passthrough,
we'll issue an Inquiry request with EVPD set to retrieve
the available VPD pages of the device. This would be done in
a way similar of what scsi_generic_read_device_identification
does: create a SCSI command and a reply buffer, fill in the
sg_io_hdr_t structure, call blk_ioctl, check if an error
occurred, process the response.
This same process is done in other 2 functions, get_device_type
and get_stream_blocksize. They differ in the command/reply
buffer and post-processing, everything else is almost a
copy/paste.
Instead of adding a forth copy/pasted-ish code when adding
the passthrough VPD BL emulation, this patch extirpates
this repetition of those 3 functions and put it into
a new one called scsi_SG_IO_FROM_DEV. Any future code that
wants to execute an SG_DXFER_FROM_DEV to the device can
use it, avoiding filling sg_io_hdr_t again and et cetera.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20180627172432.11120-3-danielhb413@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
To add support for the emulation of Block Limits VPD page
for passthrough devices, a few adjustments in the current code
base is required to avoid repetition and improve clarity.
In scsi-generic.c, detach the Inquiry handling from
scsi_read_complete and put it into a new function called
scsi_handle_inquiry_reply. This change aims to avoid
cluttering of scsi_read_complete when we more logic in the
Inquiry response handling is added in the next patches,
centralizing the changes in the new function.
In scsi-disk.c, take the build of all emulated VPD pages
from scsi_disk_emulate_inquiry and make it available to
other files into a non-static function called
scsi_disk_emulate_vpd_page. Making it public will allow
the future VPD BL emulation code for passthrough devices
to use it from scsi-generic.c, avoiding copy/pasting this
code solely for that purpose. It also has the advantage of
providing emulation of all VPD pages in case we need to
emulate other pages in other scenarios. As a bonus,
scsi_disk_emulate_inquiry got tidier.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20180627172432.11120-2-danielhb413@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Remove those unneeded includes to speed up the compilation
process a little bit.
Code change produced with:
$ git grep '#include "sysemu/blockdev.h"' | \
cut -d: -f-1 | \
xargs egrep -L "(BlockInterfaceType|DriveInfo|drive_get|blk_legacy_dinfo|blockdev_mark_auto_del)" | \
xargs sed -i.bak '/#include "sysemu\/blockdev.h"/d'
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20180528232719.4721-15-f4bug@amsat.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
QEMU SCSI code makes assumptions about how the PROTECT and BYTCHK
works in the protocol, denying support for PI (Protection
Information) in case the guest OS requests it. However, in SCSI versions 2
and older, there is no PI concept in the protocol.
This means that when dealing with such devices:
- there is no PROTECT bit in byte 5 of the standard INQUIRY response. The
whole byte is marked as "Reserved";
- there is no RDPROTECT in byte 2 of READ. We have 'Logical Unit Number'
in this field instead;
- there is no VRPROTECT in byte 2 of VERIFY. We have 'Logical Unit Number'
in this field instead. This also means that the BYTCHK bit in this case
is not related to PI.
Since QEMU does not consider these changes, a SCSI passthrough using
a SCSI-2 device will not work. It will mistake these fields with
PI information and return Illegal Request SCSI SENSE thinking
that the driver is asking for PI support.
This patch fixes it by adding a new attribute called 'scsi_version'
that is read from the standard INQUIRY response of passthrough
devices. This allows for a version verification before applying
conditions related to PI that doesn't apply for older versions.
Reported-by: Dac Nguyen <dacng@us.ibm.com>
Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Message-Id: <20180327211451.14647-1-danielhb@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We would like to have different behavior for passthrough devices
depending on the SCSI version they expose. To prepare for that,
allow the user of emulated devices to specify the desired SCSI
level, and adjust the emulation according to the property value.
The next patch will set the level for scsi-block and scsi-generic
devices.
Based on a patch by Daniel Henrique Barboza
<danielhb@linux.vnet.ibm.com>.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If the user does not have permissions to send ioctls to the device (due to
SELinux or cgroups, for example), the output can look like
qemu-kvm: -device scsi-block,drive=disk: cannot get SG_IO version number:
Operation not permitted. Is this a SCSI device?
but this is confusing because the ioctl was blocked _before_ the device
even received the SG_GET_VERSION_NUM ioctl. Therefore, for EPERM errors
the suggestion should be eliminated. To make that simpler, change the
code to use error_append_hint.
Reported-by: Ala Hino <ahino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Coverity doesn't like the ignored return value introduced in
9d3b155186 (hw/block: Fix the return type), and other callers are
converted already in ceff3e1f01.
This one was added lately in d9bcd6f7f2 and missed the train. Do it
now.
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20180118025245.13042-1-famz@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add the property to the device model, then parse it by calling
blkconf_apply_backend_options().
In addition to blk_set_perm(), the called function also handles error
options and wce. For error options we've already checked that the
default values are used, for wce we don't have the option either so it
is always the default (true). In other words there is no change of
behavior in these regards.
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20171205151553.7834-1-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Complete the transition by renaming this header, which was
shared by block/iscsi.c and the SCSI emulation code.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move more knowledge of SG_IO out of hw/scsi/scsi-generic.c, for
reusability.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
util/scsi.c includes some SCSI code that is shared by block/iscsi.c and
hw/scsi, but the introduction of the persistent reservation helper
will add many more instances of this. There is also include/block/scsi.h,
which actually is not part of the core block layer.
The persistent reservation manager will also need a home. A scsi/
directory provides one for both the aforementioned shared code and
the PR manager code.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
On NetBSD, where tolower() and toupper() are implemented using an
array lookup, the compiler warns if you pass a plain 'char'
to these functions:
gdbstub.c:914:13: warning: array subscript has type 'char'
This reflects the fact that toupper() and tolower() give
undefined behaviour if they are passed a value that isn't
a valid 'unsigned char' or EOF.
We have qemu_tolower() and qemu_toupper() to avoid this problem;
use them.
(The use in scsi-generic.c does not trigger the warning because
it passes a uint8_t; we switch it anyway, for consistency.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> for the s390 part.
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Message-id: 1500568290-7966-1-git-send-email-peter.maydell@linaro.org
When opt_xfer_len is zero, Linux ignores max_xfer_len erroneously.
While that obviously should be fixed, we do older guests a favor to
always filling in a value.
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170327142625.1249-1-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-16-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When running with debug enabled, the scsi-generic cdb that is
dumped skips byte 0 of the command, which is the opcode. This
makes identifying which command is being issued/completed a
little difficult. Example:
0x00 0x00 0x01 0x00 0x00
scsi-generic: scsi_read_data 0x0
scsi-generic: Data ready tag=0x0 len=164
scsi-generic: scsi_read_data 0x0
scsi-generic: Command complete 0x0x10a42c60 tag=0x0 status=0
Improve this by adding a message prior to the loop, similar to
what exists for scsi-disk. Clean up a few other messages to be
more explicit of what is being represented. Example:
scsi-generic: Command: data=0x12 0x00 0x00 0x01 0x00 0x00
scsi-generic: scsi_read_data tag=0x0
scsi-generic: Data ready tag=0x0 len=164
scsi-generic: scsi_read_data tag=0x0
scsi-generic: Command complete 0x0x10a452d0 tag=0x0 status=0
Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com>
Message-Id: <20170120162527.66075-2-farman@linux.vnet.ibm.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Sector-based limits are awkward to think about; in our on-going
quest to move to byte-based interfaces, convert max_transfer_length
and opt_transfer_length. Rename them (dropping the _length suffix)
so that the compiler will help us catch the change in semantics
across any rebased code, and improve the documentation. Use unsigned
values, so that we don't have to worry about negative values and
so that bit-twiddling is easier; however, we are still constrained
by 2^31 of signed int in most APIs.
When a value comes from an external source (iscsi and raw-posix),
sanitize the results to ensure that opt_transfer is a power of 2.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Making all callers special-case 0 as unlimited is awkward,
and we DO have a hard maximum of BDRV_REQUEST_MAX_SECTORS given
our current block layer API limits.
In the case of scsi, this means that we now always advertise a
limit to the guest, even in cases where the underlying layers
previously use 0 for no inherent limit beyond the block layer.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
s->blocksize may be larger than 512, in which case our
tweaks to max_xfer_len and opt_xfer_len must be scaled
appropriately.
CC: qemu-stable@nongnu.org
Reported-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Use Coccinelle script to replace 'ret = E; return ret' with
'return E'. The script will do the substitution only when the
function return type and variable type are the same.
Manual fixups:
* audio/audio.c: coding style of "read (...)" and "write (...)"
* block/qcow2-cluster.c: wrap line to make it shorter
* block/qcow2-refcount.c: change indentation of wrapped line
* target-tricore/op_helper.c: fix coding style of
"remainder|quotient"
* target-mips/dsp_helper.c: reverted changes because I don't
want to argue about checkpatch.pl
* ui/qemu-pixman.c: fix line indentation
* block/rbd.c: restore blank line between declarations and
statements
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <1465855078-19435-4-git-send-email-ehabkost@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Unused Coccinelle rule name dropped along with a redundant comment;
whitespace touched up in block/qcow2-cluster.c; stale commit message
paragraph deleted]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The rationale is similar to the above mode sense response interception:
this is practically the only channel to communicate restraints from
elsewhere such as host and block driver.
The scsi bus we attach onto can have a larger max xfer len than what is
accepted by the host file system (guarding between the host scsi LUN and
QEMU), in which case the SG_IO we generate would get -EINVAL.
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <1464243305-10661-3-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef. Since then, we've moved to include qemu/osdep.h
everywhere. Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h. That's in excess of
100KiB of crap most .c files don't actually need.
Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h. Include qapi/error.h in .c files that need it and don't
get it now. Include qapi-types.h in qom/object.h for uint16List.
Update scripts/clean-includes accordingly. Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h. Update the list of includes in the qemu/osdep.h
comment quoted above similarly.
This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third. Unfortunately, the number depending on
qapi-types.h shrinks only a little. More work is needed for that one.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-24-git-send-email-peter.maydell@linaro.org
Passed-through SCSI devices can be opened with the readonly=on option.
When this happens, Linux filters away write commands so that the guest
cannot overwrite the contents of the device.
However, the guest does not know that the device is read-only, and
accepts writes. The writes only fail later when the page cache is
flushed.
This patch modifies scsi-generic to modify the MODE SENSE data and
set the read-only bit in the device-specific parameters, so that
the guest OS treats the disk as write protected.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
