qemu: add support for discard_granularity

This commit adds building of `discard_granularity` disk option
for qemu commandline.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1849570

Signed-off-by: Kristina Hanicova <khanicov@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>

src/qemu/qemu_command.c

@@ -1760,6 +1760,7 @@ qemuBuildDiskDeviceProps(const virDomainDef *def,
     unsigned int bootindex = 0;
     unsigned int logical_block_size = disk->blockio.logical_block_size;
     unsigned int physical_block_size = disk->blockio.physical_block_size;
+    unsigned int discard_granularity = disk->blockio.discard_granularity;
     g_autoptr(virJSONValue) wwn = NULL;
     g_autofree char *serial = NULL;
     virTristateSwitch removable = VIR_TRISTATE_SWITCH_ABSENT;
@@ -1939,6 +1940,7 @@ qemuBuildDiskDeviceProps(const virDomainDef *def,
                               "p:bootindex", bootindex,
                               "p:logical_block_size", logical_block_size,
                               "p:physical_block_size", physical_block_size,
+                              "p:discard_granularity", discard_granularity,
                               "A:wwn", &wwn,
                               "p:rotation_rate", disk->rotation_rate,
                               "S:vendor", disk->vendor,

tests/qemuxml2argvdata/disk-blockio.x86_64-latest.args

@@ -32,7 +32,7 @@ XDG_CONFIG_HOME=/var/lib/libvirt/qemu/domain--1-QEMUGuest1/.config \
 -device '{"driver":"ide-cd","bus":"ide.0","unit":1,"drive":"libvirt-2-format","id":"ide0-0-1"}' \
 -blockdev '{"driver":"file","filename":"/tmp/idedisk.img","node-name":"libvirt-1-storage","auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"driver":"raw","file":"libvirt-1-storage"}' \
--device '{"driver":"ide-hd","bus":"ide.0","unit":2,"drive":"libvirt-1-format","id":"ide0-0-2","bootindex":1,"logical_block_size":512,"physical_block_size":512}' \
+-device '{"driver":"ide-hd","bus":"ide.0","unit":2,"drive":"libvirt-1-format","id":"ide0-0-2","bootindex":1,"logical_block_size":512,"physical_block_size":512,"discard_granularity":4096}' \
 -audiodev '{"id":"audio1","driver":"none"}' \
 -device '{"driver":"virtio-balloon-pci","id":"balloon0","bus":"pci.0","addr":"0x2"}' \
 -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny \

tests/qemuxml2argvdata/disk-blockio.xml

@@ -23,7 +23,7 @@
       <source file='/tmp/idedisk.img'/>
       <target dev='hdc' bus='ide'/>
       <address type='drive' controller='0' bus='0' target='0' unit='2'/>
-      <blockio logical_block_size='512' physical_block_size='512'/>
+      <blockio logical_block_size='512' physical_block_size='512' discard_granularity='4096'/>
     </disk>
     <controller type='usb' index='0'/>
     <controller type='ide' index='0'/>

tests/qemuxml2xmloutdata/disk-blockio.x86_64-latest.xml

@@ -0,0 +1,48 @@
+<domain type='qemu'>
+  <name>QEMUGuest1</name>
+  <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+  <memory unit='KiB'>219136</memory>
+  <currentMemory unit='KiB'>219136</currentMemory>
+  <vcpu placement='static'>1</vcpu>
+  <os>
+    <type arch='x86_64' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <cpu mode='custom' match='exact' check='none'>
+    <model fallback='forbid'>qemu64</model>
+  </cpu>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu-system-x86_64</emulator>
+    <disk type='block' device='cdrom'>
+      <driver name='qemu' type='raw'/>
+      <source dev='/dev/HostVG/QEMUGuest1'/>
+      <target dev='hda' bus='ide'/>
+      <readonly/>
+      <address type='drive' controller='0' bus='0' target='0' unit='1'/>
+    </disk>
+    <disk type='file' device='disk'>
+      <driver name='qemu' type='raw'/>
+      <source file='/tmp/idedisk.img'/>
+      <blockio logical_block_size='512' physical_block_size='512' discard_granularity='4096'/>
+      <target dev='hdc' bus='ide'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='2'/>
+    </disk>
+    <controller type='usb' index='0' model='piix3-uhci'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
+    </controller>
+    <controller type='ide' index='0'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
+    </controller>
+    <controller type='pci' index='0' model='pci-root'/>
+    <input type='mouse' bus='ps2'/>
+    <input type='keyboard' bus='ps2'/>
+    <audio id='1' type='none'/>
+    <memballoon model='virtio'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
+    </memballoon>
+  </devices>
+</domain>

tests/qemuxml2xmltest.c

@@ -288,6 +288,7 @@ mymain(void)
     DO_TEST_CAPS_LATEST("disk-floppy");
     DO_TEST_CAPS_LATEST("disk-usb-device");
     DO_TEST_CAPS_LATEST("disk-virtio");
+    DO_TEST_CAPS_LATEST("disk-blockio");
     DO_TEST_CAPS_LATEST("floppy-drive-fat");
     DO_TEST_CAPS_LATEST("disk-virtio-queues");
     DO_TEST_CAPS_LATEST("disk-boot-disk");