Generated from hardware using the following command and then padding
with 0xff to fill out a power-of-2:
xxd -p /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
Cc: Michael Walle <michael@walle.cc>
Cc: Tudor Ambarus <tudor.ambarus@linaro.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Message-Id: <20221221122213.1458540-1-linux@roeck-us.net>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Generated from hardware using the following command and then padding
with 0xff to fill out a power-of-2:
hexdump -v -e '8/1 "0x%02x, " "\n"' sfdp`
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
[ clg: removed extern ]
Message-Id: <20221006224424.3556372-1-patrick@stwcx.xyz>
Message-Id: <20221013161241.2805140-10-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The SFDP table size is 0x100 bytes long. The mandatory table for basic
features is available at byte 0x80 and two extra Winbond specifics
table are available at 0xC0 and 0xF0.
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
Message-Id: <20220722063602.128144-8-clg@kaod.org>
Message-Id: <20221013161241.2805140-9-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The SFDP table size is 0x100 bytes long. Only the mandatory table for
basic features is available at byte 0x80.
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
Message-Id: <20220722063602.128144-7-clg@kaod.org>
Message-Id: <20221013161241.2805140-8-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The SFDP table size is 0x200 bytes long. The mandatory table for basic
features is available at byte 0x30 plus some more Macronix specific
tables.
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
Message-Id: <20220722063602.128144-6-clg@kaod.org>
Message-Id: <20221013161241.2805140-7-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The mx25l25635e and mx25l25635f chips have the same JEDEC id but the
mx25l25635f has more capabilities reported in the SFDP table. Support
for 4B opcodes is of interest because it is exploited by the Linux
kernel.
The SFDP table size is 0x200 bytes long. The mandatory table for basic
features is available at byte 0x30 and an extra Macronix specific
table is available at 0x60.
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
Message-Id: <20220722063602.128144-5-clg@kaod.org>
Message-Id: <20221013161241.2805140-6-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The SFDP table is 0x80 bytes long. The mandatory table for basic
features is available at byte 0x30 and an extra Macronix specific
table is available at 0x60.
4B opcodes are not supported.
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
Message-Id: <20220722063602.128144-4-clg@kaod.org>
Message-Id: <20221013161241.2805140-5-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The same values were collected on 4 differents OpenPower systems,
palmettos, romulus and tacoma.
The SFDP table size is defined as being 0x100 bytes but it could be
bigger. Only the mandatory table for basic features is available at
byte 0x30.
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
Message-Id: <20220722063602.128144-3-clg@kaod.org>
Message-Id: <20221013161241.2805140-3-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
JEDEC STANDARD JESD216 for Serial Flash Discovery Parameters (SFDP)
provides a mean to describe the features of a serial flash device
using a set of internal parameter tables.
This is the initial framework for the RDSFDP command giving access to
a private SFDP area under the flash. This area now needs to be
populated with the flash device characteristics, using a new
'sfdp_read' handler under FlashPartInfo.
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
Message-Id: <20220722063602.128144-2-clg@kaod.org>
Message-Id: <20221013161241.2805140-2-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Swap 'buf' and 'bytes' around for consistency with
blk_co_{pread,pwrite}(), and in preparation to implement these functions
using generated_co_wrapper.
Callers were updated using this Coccinelle script:
@@ expression blk, offset, buf, bytes, flags; @@
- blk_pread(blk, offset, buf, bytes, flags)
+ blk_pread(blk, offset, bytes, buf, flags)
@@ expression blk, offset, buf, bytes, flags; @@
- blk_pwrite(blk, offset, buf, bytes, flags)
+ blk_pwrite(blk, offset, bytes, buf, flags)
It had no effect on hw/block/nand.c, presumably due to the #if, so that
file was updated manually.
Overly-long lines were then fixed by hand.
Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220705161527.1054072-4-afaria@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
For consistency with other I/O functions, and in preparation to
implement it using generated_co_wrapper.
Callers were updated using this Coccinelle script:
@@ expression blk, offset, buf, bytes; @@
- blk_pread(blk, offset, buf, bytes)
+ blk_pread(blk, offset, buf, bytes, 0)
It had no effect on hw/block/nand.c, presumably due to the #if, so that
file was updated manually.
Overly-long lines were then fixed by hand.
Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220705161527.1054072-3-afaria@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
They currently return the value of their 'bytes' parameter on success.
Make them return 0 instead, for consistency with other I/O functions and
in preparation to implement them using generated_co_wrapper. This also
makes it clear that short reads/writes are not possible.
Signed-off-by: Alberto Faria <afaria@redhat.com>
Message-Id: <20220705161527.1054072-2-afaria@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
The write_enable latch property is not currently exposed.
This commit makes it a modifiable property.
Signed-off-by: Iris Chen <irischenlj@fb.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
Message-Id: <20220513055022.951759-1-irischenlj@fb.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The w25q01jvq is a 128MB part. Support is being added to the kernel[1]
and the two have been tested together.
1. https://lore.kernel.org/lkml/20220222092222.23108-1-potin.lai@quantatw.com/
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Cc: Potin Lai <potin.lai@quantatw.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
Message-Id: <20220304180920.1780992-1-patrick@stwcx.xyz>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Add support for Micron Xccela flash mt35xu01g.
Signed-off-by: Francisco Iglesias <francisco.iglesias@xilinx.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 20220121161141.14389-9-francisco.iglesias@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The Micron mt25ql02g is a 3V 2Gb serial NOR flash memory supporting
dual I/O and quad I/O, 4KB, 32KB, 64KB sector erase. It also supports
4B opcodes. The mt25qu02g operates at 1.8V.
https://4donline.ihs.com/images/VipMasterIC/IC/MICT/MICT-S-A0008500026/MICT-S-A0008511423-1.pdf?hkey=52A5661711E402568146F3353EA87419
Cc: Alistair Francis <alistair.francis@wdc.com>
Cc: Francisco Iglesias <francisco.iglesias@xilinx.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Francisco Iglesias <francisco.iglesias@xilinx.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Per SST25VF016B datasheet [1], SST flash requires a dummy byte after
the address bytes. Note only SPI mode is supported by SST flashes.
[1] http://ww1.microchip.com/downloads/en/devicedoc/s71271_04.pdf
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20210306060152.7250-1-bmeng.cn@gmail.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
This updates the flash information table to include various ISSI
flashes that are supported by upstream U-Boot and Linux kernel.
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20210126060007.12904-3-bmeng.cn@gmail.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
This adds the ISSI SPI flash support. The number of dummy cycles in
fast read, fast read dual output and fast read quad output commands
is currently using the default 8. Likewise, the same default value
is used for fast read dual/quad I/O command. Per the datasheet [1],
the number of dummy cycles is configurable, but this is not modeled
at present.
For flash whose size is larger than 16 MiB, the sequence of 3-byte
address along with EXTADD bit in the bank address register (BAR) is
not supported. We assume that guest software always uses op codes
with 4-byte address sequence. Fortunately, this is the case for both
U-Boot and Linux spi-nor drivers.
QPI (Quad Peripheral Interface) that supports 2-cycle instruction
has different default values for dummy cycles of fast read family
commands, and is unsupported at the time being.
[1] http://www.issi.com/WW/pdf/25LP-WP256.pdf
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20210126060007.12904-2-bmeng.cn@gmail.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.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>
Auto Address Increment (AAI) Word-Program is a special command of
SST flashes. AAI-WP allows multiple bytes of data to be programmed
without re-issuing the next sequential address location.
Signed-off-by: Xuzhou Cheng <xuzhou.cheng@windriver.com>
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
Message-id: 1608688825-81519-2-git-send-email-bmeng.cn@gmail.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
When write is disabled, the write to flash should be avoided
in flash_write8().
Fixes: 82a2499011 ("m25p80: Initial implementation of SPI flash device")
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
Message-id: 1608688825-81519-1-git-send-email-bmeng.cn@gmail.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.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>
Some Numonyx flash commands cannot be executed in DIO and QIO mode, such as
trying to do DPP or DOR when in QIO mode.
Signed-off-by: Joe Komlodi <komlodi@xilinx.com>
Reviewed-by: Francisco Iglesias <francisco.iglesias@xilinx.com>
Message-id: 1605568264-26376-4-git-send-email-komlodi@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
VCFG XIP is set (disabled) when the NVCFG XIP bits are all set (disabled).
Signed-off-by: Joe Komlodi <komlodi@xilinx.com>
Reviewed-by: Francisco Iglesias <francisco.iglesias@xilinx.com>
Message-id: 1605568264-26376-3-git-send-email-komlodi@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The previous naming of the configuration registers made it sound like that if
the bits were set the settings would be enabled, while the opposite is true.
Signed-off-by: Joe Komlodi <komlodi@xilinx.com>
Reviewed-by: Francisco Iglesias <francisco.iglesias@xilinx.com>
Message-id: 1605568264-26376-2-git-send-email-komlodi@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
In order to use inclusive terminology, rename SSI 'slave' as
'peripheral', following the specification resolution:
https://www.oshwa.org/a-resolution-to-redefine-spi-signal-names/
Patch created mechanically using:
$ sed -i s/SSISlave/SSIPeripheral/ $(git grep -l SSISlave)
$ sed -i s/SSI_SLAVE/SSI_PERIPHERAL/ $(git grep -l SSI_SLAVE)
$ sed -i s/ssi-slave/ssi-peripheral/ $(git grep -l ssi-slave)
$ sed -i s/ssi_slave/ssi_peripheral/ $(git grep -l ssi_slave)
$ sed -i s/ssi_create_slave/ssi_create_peripheral/ \
$(git grep -l ssi_create_slave)
Then in VMStateDescription vmstate_ssi_peripheral we restored
the "SSISlave" migration stream name (to avoid breaking migration).
Finally the following files have been manually tweaked:
- hw/ssi/pl022.c
- hw/ssi/xilinx_spips.c
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201012124955.3409127-4-f4bug@amsat.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Some typedefs and macros are defined after the type check macros.
This makes it difficult to automatically replace their
definitions with OBJECT_DECLARE_TYPE.
Patch generated using:
$ ./scripts/codeconverter/converter.py -i \
--pattern=QOMStructTypedefSplit $(git grep -l '' -- '*.[ch]')
which will split "typdef struct { ... } TypedefName"
declarations.
Followed by:
$ ./scripts/codeconverter/converter.py -i --pattern=MoveSymbols \
$(git grep -l '' -- '*.[ch]')
which will:
- move the typedefs and #defines above the type check macros
- add missing #include "qom/object.h" lines if necessary
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-9-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-10-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-11-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Support a following SPI flashes:
* mx66l51235f
* mt25ql512ab
Signed-off-by: Igor Kononenko <i.kononenko@yadro.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20200811203724.20699-1-i.kononenko@yadro.com>
Message-Id: <20200819100956.2216690-22-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The mx25l25635e returns the JEDEC ID twice when issuing a RDID command :
[ 2.512027] aspeed-smc 1e630000.spi: reading JEDEC ID C2:20:19:C2:20:19
This can break some firmware testing for this condition on the
supermicrox11-bmc machine.
Reported-by: Erik Smit <erik.lucas.smit@gmail.com>
Message-Id: <20200819100956.2216690-2-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Whenever an unsupported command is encountered, the current code
interprets each transferred byte as new command. Most of the time, those
'commands' are interpreted as new unknown commands. However, in rare
cases, it may be that for example address or length information
passed with the original command is by itself a valid command.
If that happens, the state machine may get completely confused and,
worst case, start writing data into the flash or even erase it.
To avoid the problem, transition into STATE_READING_DATA and keep
sending a value of 0 until the chip is deselected after encountering
an unsupported command.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When requesting JEDEC data using the JEDEC_READ command, the Linux kernel
always requests 6 bytes. The current implementation only returns three
bytes, and interprets the remaining three bytes as new commands.
While this does not matter most of the time, it is at the very least
confusing. To avoid the problem, always report up to 6 bytes of JEDEC
data. Fill remaining data with 0.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
While at it, add some trace messages to help debug problems
seen when running the latest Linux kernel.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Message-id: 20190925143248.10000-20-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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 hw/hw.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 previous commits have left only the declaration of hw_error() in
hw/hw.h. This permits dropping most of its inclusions. Touching it
now recompiles less than 200 objects.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-19-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
In my "build everything" tree, changing migration/vmstate.h triggers a
recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).
hw/hw.h supposedly includes it for convenience. Several other headers
include it just to get VMStateDescription. The previous commit made
that unnecessary.
Include migration/vmstate.h only where it's still needed. Touching it
now recompiles only some 1600 objects.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-16-armbru@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
It eases code review, unit is explicit.
Patch generated using:
$ git grep -E '(1024|2048|4096|8192|(<<|>>).?(10|20|30))' hw/ include/hw/
and modified manually.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20180625124238.25339-14-f4bug@amsat.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
On Macronix chips, two bytes can written to the WRSR. First byte will
configure the status register and the second the configuration
register. It is important to save the configuration value as it
contains the dummy cycle setting when using dual or quad IO mode.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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>
The point of writing a macro embedded in a 'do { ... } while (0)'
loop (particularly if the macro has multiple statements or would
otherwise end with an 'if' statement) is so that the macro can be
used as a drop-in statement with the caller supplying the
trailing ';'. Although our coding style frowns on brace-less 'if':
if (cond)
statement;
else
something else;
that is the classic case where failure to use do/while(0) wrapping
would cause the 'else' to pair with any embedded 'if' in the macro
rather than the intended outer 'if'. But conversely, if the macro
includes an embedded ';', then the same brace-less coding style
would now have two statements, making the 'else' a syntax error
rather than pairing with the outer 'if'. Thus, even though our
coding style with required braces is not impacted, ending a macro
with ';' makes our code harder to port to projects that use
brace-less styles.
The change should have no semantic impact. I was not able to
fully compile-test all of the changes (as some of them are
examples of the ugly bit-rotting debug print statements that are
completely elided by default, and I didn't want to recompile
with the necessary -D witnesses - cleaning those up is left as a
bite-sized task for another day); I did, however, audit that for
all files touched, all callers of the changed macros DID supply
a trailing ';' at the callsite, and did not appear to be used
as part of a brace-less conditional.
Found mechanically via: $ git grep -B1 'while (0);' | grep -A1 \\\\
Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20171201232433.25193-7-eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
