mirror of
https://gitlab.com/libvirt/libvirt.git
synced 2025-03-07 17:28:15 +00:00
Add support for hotplug/unplug of disk devices in LXC
Wire up the attach/detach device drivers in LXC to support the hotplug/unplug of disks. Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This commit is contained in:
Daniel P. Berrange
parent
986c270dac
commit
de858e3fa7
@ -30,6 +30,7 @@
|
||||
#include <string.h>
|
||||
#include <sys/types.h>
|
||||
#include <sys/socket.h>
|
||||
#include <sys/stat.h>
|
||||
#include <sys/un.h>
|
||||
#include <sys/poll.h>
|
||||
#include <unistd.h>
|
||||
@ -3091,6 +3092,136 @@ cleanup:
|
||||
}
|
||||
|
||||
|
||||
static int
|
||||
lxcDomainAttachDeviceDiskLive(virLXCDriverPtr driver,
|
||||
virDomainObjPtr vm,
|
||||
virDomainDeviceDefPtr dev)
|
||||
{
|
||||
virLXCDomainObjPrivatePtr priv = vm->privateData;
|
||||
virDomainDiskDefPtr def = dev->data.disk;
|
||||
virCgroupPtr group = NULL;
|
||||
int ret = -1;
|
||||
char *dst;
|
||||
struct stat sb;
|
||||
bool created = false;
|
||||
mode_t mode = 0;
|
||||
char *tmpsrc = def->src;
|
||||
|
||||
if (!priv->initpid) {
|
||||
virReportError(VIR_ERR_OPERATION_INVALID, "%s",
|
||||
_("Cannot attach disk until init PID is known"));
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
if (def->type != VIR_DOMAIN_DISK_TYPE_BLOCK) {
|
||||
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
|
||||
_("Can't setup disk for non-block device"));
|
||||
goto cleanup;
|
||||
}
|
||||
if (def->src == NULL) {
|
||||
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
|
||||
_("Can't setup disk without media"));
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
if (virDomainDiskIndexByName(vm->def, def->dst, true) >= 0) {
|
||||
virReportError(VIR_ERR_OPERATION_FAILED,
|
||||
_("target %s already exists"), def->dst);
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
if (stat(def->src, &sb) < 0) {
|
||||
virReportSystemError(errno,
|
||||
_("Unable to access %s"), def->src);
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
if (!S_ISCHR(sb.st_mode) && !S_ISBLK(sb.st_mode)) {
|
||||
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
|
||||
_("Disk source %s must be a character/block device"),
|
||||
def->src);
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
if (virAsprintf(&dst, "/proc/%llu/root/dev/%s",
|
||||
(unsigned long long)priv->initpid, def->dst) < 0) {
|
||||
virReportOOMError();
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
if (VIR_REALLOC_N(vm->def->disks, vm->def->ndisks+1) < 0) {
|
||||
virReportOOMError();
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
mode = 0700;
|
||||
if (S_ISCHR(sb.st_mode))
|
||||
mode |= S_IFCHR;
|
||||
else
|
||||
mode |= S_IFBLK;
|
||||
|
||||
/* Yes, the device name we're creating may not
|
||||
* actually correspond to the major:minor number
|
||||
* we're using, but we've no other option at this
|
||||
* time. Just have to hope that containerized apps
|
||||
* don't get upset that the major:minor is different
|
||||
* to that normally implied by the device name
|
||||
*/
|
||||
VIR_DEBUG("Creating dev %s (%d,%d) from %s",
|
||||
dst, major(sb.st_rdev), minor(sb.st_rdev), def->src);
|
||||
if (mknod(dst, mode, sb.st_rdev) < 0) {
|
||||
virReportSystemError(errno,
|
||||
_("Unable to create device %s"),
|
||||
dst);
|
||||
goto cleanup;
|
||||
}
|
||||
created = true;
|
||||
|
||||
/* Labelling normally operates on src, but we need
|
||||
* to actally label the dst here, so hack the config */
|
||||
def->src = dst;
|
||||
if (virSecurityManagerSetImageLabel(driver->securityManager,
|
||||
vm->def, def) < 0)
|
||||
goto cleanup;
|
||||
|
||||
if (!lxcCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_DEVICES)) {
|
||||
virReportError(VIR_ERR_OPERATION_INVALID, "%s",
|
||||
_("devices cgroup isn't mounted"));
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
if (virCgroupForDomain(driver->cgroup, vm->def->name, &group, 0) != 0) {
|
||||
virReportError(VIR_ERR_INTERNAL_ERROR,
|
||||
_("cannot find cgroup for domain %s"), vm->def->name);
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
if (virCgroupAllowDevicePath(group, def->src,
|
||||
(def->readonly ?
|
||||
VIR_CGROUP_DEVICE_READ :
|
||||
VIR_CGROUP_DEVICE_RW) |
|
||||
VIR_CGROUP_DEVICE_MKNOD) != 0) {
|
||||
virReportError(VIR_ERR_INTERNAL_ERROR,
|
||||
_("cannot allow device %s for domain %s"),
|
||||
def->src, vm->def->name);
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
virDomainDiskInsertPreAlloced(vm->def, def);
|
||||
|
||||
ret = 0;
|
||||
|
||||
cleanup:
|
||||
def->src = tmpsrc;
|
||||
virDomainAuditDisk(vm, NULL, def->src, "attach", ret == 0);
|
||||
if (group)
|
||||
virCgroupFree(&group);
|
||||
if (dst && created && ret < 0)
|
||||
unlink(dst);
|
||||
return ret;
|
||||
}
|
||||
|
||||
|
||||
static int
|
||||
lxcDomainAttachDeviceLive(virLXCDriverPtr driver ATTRIBUTE_UNUSED,
|
||||
virDomainObjPtr vm ATTRIBUTE_UNUSED,
|
||||
@ -3099,6 +3230,12 @@ lxcDomainAttachDeviceLive(virLXCDriverPtr driver ATTRIBUTE_UNUSED,
|
||||
int ret = -1;
|
||||
|
||||
switch (dev->type) {
|
||||
case VIR_DOMAIN_DEVICE_DISK:
|
||||
ret = lxcDomainAttachDeviceDiskLive(driver, vm, dev);
|
||||
if (!ret)
|
||||
dev->data.disk = NULL;
|
||||
break;
|
||||
|
||||
default:
|
||||
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
|
||||
_("device type '%s' cannot be attached"),
|
||||
@ -3110,6 +3247,77 @@ lxcDomainAttachDeviceLive(virLXCDriverPtr driver ATTRIBUTE_UNUSED,
|
||||
}
|
||||
|
||||
|
||||
static int
|
||||
lxcDomainDetachDeviceDiskLive(virLXCDriverPtr driver,
|
||||
virDomainObjPtr vm,
|
||||
virDomainDeviceDefPtr dev)
|
||||
{
|
||||
virLXCDomainObjPrivatePtr priv = vm->privateData;
|
||||
virDomainDiskDefPtr def = NULL;
|
||||
virCgroupPtr group = NULL;
|
||||
int i, ret = -1;
|
||||
char *dst;
|
||||
|
||||
if (!priv->initpid) {
|
||||
virReportError(VIR_ERR_OPERATION_INVALID, "%s",
|
||||
_("Cannot attach disk until init PID is known"));
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
if ((i = virDomainDiskIndexByName(vm->def,
|
||||
dev->data.disk->dst,
|
||||
false)) < 0) {
|
||||
virReportError(VIR_ERR_OPERATION_FAILED,
|
||||
_("disk %s not found"), dev->data.disk->dst);
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
def = vm->def->disks[i];
|
||||
|
||||
if (virAsprintf(&dst, "/proc/%llu/root/dev/%s",
|
||||
(unsigned long long)priv->initpid, def->dst) < 0) {
|
||||
virReportOOMError();
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
if (!lxcCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_DEVICES)) {
|
||||
virReportError(VIR_ERR_OPERATION_INVALID, "%s",
|
||||
_("devices cgroup isn't mounted"));
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
if (virCgroupForDomain(driver->cgroup, vm->def->name, &group, 0) != 0) {
|
||||
virReportError(VIR_ERR_INTERNAL_ERROR,
|
||||
_("cannot find cgroup for domain %s"), vm->def->name);
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
VIR_DEBUG("Unlinking %s (backed by %s)", dst, def->src);
|
||||
if (unlink(dst) < 0 && errno != ENOENT) {
|
||||
virDomainAuditDisk(vm, def->src, NULL, "detach", false);
|
||||
virReportSystemError(errno,
|
||||
_("Unable to remove device %s"), dst);
|
||||
goto cleanup;
|
||||
}
|
||||
virDomainAuditDisk(vm, def->src, NULL, "detach", true);
|
||||
|
||||
if (virCgroupDenyDevicePath(group, def->src, VIR_CGROUP_DEVICE_RWM) != 0)
|
||||
VIR_WARN("cannot deny device %s for domain %s",
|
||||
def->src, vm->def->name);
|
||||
|
||||
virDomainDiskRemove(vm->def, i);
|
||||
virDomainDiskDefFree(def);
|
||||
|
||||
ret = 0;
|
||||
|
||||
cleanup:
|
||||
VIR_FREE(dst);
|
||||
if (group)
|
||||
virCgroupFree(&group);
|
||||
return ret;
|
||||
}
|
||||
|
||||
|
||||
static int
|
||||
lxcDomainDetachDeviceLive(virLXCDriverPtr driver ATTRIBUTE_UNUSED,
|
||||
virDomainObjPtr vm ATTRIBUTE_UNUSED,
|
||||
@ -3118,6 +3326,10 @@ lxcDomainDetachDeviceLive(virLXCDriverPtr driver ATTRIBUTE_UNUSED,
|
||||
int ret = -1;
|
||||
|
||||
switch (dev->type) {
|
||||
case VIR_DOMAIN_DEVICE_DISK:
|
||||
ret = lxcDomainDetachDeviceDiskLive(driver, vm, dev);
|
||||
break;
|
||||
|
||||
default:
|
||||
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
|
||||
_("device type '%s' cannot be detached"),
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user