qemu/hw
Kevin Wolf 86b1cf3227 block: Separate blk_is_writable() and blk_supports_write_perm()
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>
2021-01-27 20:45:20 +01:00
..
9pfs 9pfs: Convert reclaim list to QSLIST 2021-01-22 18:26:40 +01:00
acpi acpi: Add addr offset in build_crs 2021-01-17 06:42:54 -05:00
adc hw/adc: Add an ADC module for NPCM7XX 2021-01-12 21:19:02 +00:00
alpha vl: extract softmmu/datadir.c 2020-12-10 12:15:18 -05:00
arm hw/*: Use type casting for SysBusDevice in NPCM7XX 2021-01-12 21:19:02 +00:00
audio audio/via-ac97: Simplify code and set user_creatable to false 2021-01-04 23:24:44 +01:00
avr vl: extract softmmu/datadir.c 2020-12-10 12:15:18 -05:00
block block: Separate blk_is_writable() and blk_supports_write_perm() 2021-01-27 20:45:20 +01:00
char Remove superfluous timer_del() calls 2021-01-08 15:13:38 +00:00
core clock: Define and use new clock_display_freq() 2021-01-04 23:24:44 +01:00
cpu cpu/core: Register core-id and nr-threads as class properties 2020-09-22 16:48:29 -04:00
cris cris: do not use ram_size global 2020-12-10 12:15:07 -05:00
display migration: Replace migration's JSON writer by the general one 2020-12-19 10:39:16 +01:00
dma hw/dma/xilinx_axidma: Rename StreamSlave as StreamSink 2020-12-10 12:15:04 -05:00
gpio nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
hppa hw: Use the PCI_SLOT() macro from 'hw/pci/pci.h' 2021-01-04 23:24:44 +01:00
hyperv qdev: Move softmmu properties to qdev-properties-system.h 2020-12-18 15:20:17 -05:00
i2c nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
i386 acpi: Add addr offset in build_crs 2021-01-17 06:42:54 -05:00
ide block: Separate blk_is_writable() and blk_supports_write_perm() 2021-01-27 20:45:20 +01:00
input Remove superfluous timer_del() calls 2021-01-08 15:13:38 +00:00
intc hw/intc/ppc-uic: Make default dcr-base 0xc0, not 0x30 2021-01-19 10:20:29 +11:00
ipack Use OBJECT_DECLARE_SIMPLE_TYPE when possible 2020-09-18 14:12:32 -04:00
ipmi Remove superfluous timer_del() calls 2021-01-08 15:13:38 +00:00
isa vt82c686: Rename superio config related parts 2021-01-04 23:24:44 +01:00
lm32 vl: extract softmmu/datadir.c 2020-12-10 12:15:18 -05:00
m68k hw/m68k/next-cube: Add vmstate for NeXTPC device 2021-01-19 09:11:52 +01:00
mem hw/*: Use type casting for SysBusDevice in NPCM7XX 2021-01-12 21:19:02 +00:00
microblaze vl: make qemu_get_machine_opts static 2020-12-15 12:51:55 -05:00
mips docs/system: Remove deprecated 'fulong2e' machine alias 2021-01-14 17:13:54 +01:00
misc block: Separate blk_is_writable() and blk_supports_write_perm() 2021-01-27 20:45:20 +01:00
moxie moxie: do not use ram_size global 2020-12-10 12:15:08 -05:00
net net: checksum: Introduce fine control over checksum type 2021-01-25 17:04:56 +08:00
nios2 * New -action option and set-action QMP command (Alejandro) 2020-12-15 21:24:31 +00:00
nubus meson: convert hw/nubus 2020-08-21 06:30:25 -04:00
nvram hw/*: Use type casting for SysBusDevice in NPCM7XX 2021-01-12 21:19:02 +00:00
openrisc target/openrisc: Move pic_cpu code into CPU object proper 2020-12-15 12:04:30 +00:00
pci pci/shpc: don't push attention button when ejecting powered-off device 2021-01-13 09:06:37 -05:00
pci-bridge Kconfig: Compile PXB for ARM_VIRT 2021-01-17 06:42:54 -05:00
pci-host acpi/gpex: Exclude pxb's resources from PCI0 2021-01-17 06:42:54 -05:00
pcmcia pxa2xx: Move QOM macros to header 2020-08-27 14:04:55 -04:00
ppc block: Separate blk_is_writable() and blk_supports_write_perm() 2021-01-27 20:45:20 +01:00
rdma Machine queue, 2020-12-23 2021-01-01 22:57:15 +00:00
riscv riscv: Pass RISCVHartArrayState by pointer 2021-01-16 14:34:46 -08:00
rtc pl031: Use timer_free() in the finalize function to avoid memleaks 2021-01-18 11:51:26 +01:00
rx rx: move BIOS load from MCU to board 2020-12-10 12:15:06 -05:00
s390x Remove superfluous timer_del() calls 2021-01-08 15:13:38 +00:00
scsi block: Separate blk_is_writable() and blk_supports_write_perm() 2021-01-27 20:45:20 +01:00
sd block: Separate blk_is_writable() and blk_supports_write_perm() 2021-01-27 20:45:20 +01:00
semihosting semihosting: Implement SYS_ISERROR 2021-01-18 10:05:06 +00:00
sh4 hw: Use the PCI_SLOT() macro from 'hw/pci/pci.h' 2021-01-04 23:24:44 +01:00
smbios i386: do not use ram_size global 2020-12-10 12:15:08 -05:00
sparc sun4m: don't connect two qemu_irqs directly to the same input 2021-01-06 11:41:37 +00:00
sparc64 vl: extract softmmu/datadir.c 2020-12-10 12:15:18 -05:00
ssi hw/*: Use type casting for SysBusDevice in NPCM7XX 2021-01-12 21:19:02 +00:00
timer hw/timer: Refactor NPCM7XX Timer to use CLK clock 2021-01-12 21:19:02 +00:00
tpm tpm: tpm_spapr: Remove unused tracepoint 2021-01-25 20:56:38 -05:00
tricore tricore tcg cpus: Fix Lesser GPL version number 2020-11-15 16:40:30 +01:00
unicore32 meson: convert hw/arch* 2020-08-21 06:30:33 -04:00
usb block: Separate blk_is_writable() and blk_supports_write_perm() 2021-01-27 20:45:20 +01:00
vfio vfio-ccw: Connect the device request notifier 2021-01-21 11:19:45 +01:00
virtio hw/virtio-pci: Replace error_report() by qemu_log_mask(GUEST_ERROR) 2021-01-18 11:51:26 +01:00
watchdog Remove superfluous timer_del() calls 2021-01-08 15:13:38 +00:00
xen qdev: Move softmmu properties to qdev-properties-system.h 2020-12-18 15:20:17 -05:00
xenpv meson: convert hw/arch* 2020-08-21 06:30:33 -04:00
xtensa vl: make qemu_get_machine_opts static 2020-12-15 12:51:55 -05:00
Kconfig hw/net/can: Introduce Xilinx ZynqMP CAN controller 2020-12-10 11:30:44 +00:00
meson.build meson: convert hw/arch* 2020-08-21 06:30:33 -04:00