This patch adds a new attribute "rawio" to the "disk" element of domain XML. Valid values of "rawio" attribute are "yes" and "no". rawio='yes' indicates the disk is desirous of CAP_SYS_RAWIO. If you specify the following XML: <disk type='block' device='lun' rawio='yes'> ... </disk> the domain will be granted CAP_SYS_RAWIO. (of course, the domain have to be executed with root privilege) NOTE: - "rawio" attribute is only valid when device='lun' - At the moment, any other disks you won't use rawio can use rawio. Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com> --- docs/formatdomain.html.in | 7 +++++-- docs/schemas/domaincommon.rng | 8 ++++++++ src/conf/domain_conf.c | 36 ++++++++++++++++++++++++++++++++++++ src/conf/domain_conf.h | 3 +++ 4 files changed, 52 insertions(+), 2 deletions(-) Index: libvirt/docs/schemas/domaincommon.rng =================================================================== --- libvirt.orig/docs/schemas/domaincommon.rng +++ libvirt/docs/schemas/domaincommon.rng @@ -806,6 +806,14 @@ </attribute> </optional> <optional> + <attribute name="rawio"> + <choice> + <value>yes</value> + <value>no</value> + </choice> + </attribute> + </optional> + <optional> <ref name="snapshot"/> </optional> <choice> Index: libvirt/src/conf/domain_conf.c =================================================================== --- libvirt.orig/src/conf/domain_conf.c +++ libvirt/src/conf/domain_conf.c @@ -30,6 +30,7 @@ #include <dirent.h> #include <sys/time.h> #include <strings.h> +#include <linux/capability.h> #include "virterror_internal.h" #include "datatypes.h" @@ -2751,6 +2752,7 @@ virDomainDiskDefParseXML(virCapsPtr caps char *type = NULL; char *device = NULL; char *snapshot = NULL; + char *rawio = NULL; char *driverName = NULL; char *driverType = NULL; char *source = NULL; @@ -2795,6 +2797,8 @@ virDomainDiskDefParseXML(virCapsPtr caps snapshot = virXMLPropString(node, "snapshot"); + rawio = virXMLPropString(node, "rawio"); + cur = node->children; while (cur != NULL) { if (cur->type == XML_ELEMENT_NODE) { @@ -3103,6 +3107,26 @@ virDomainDiskDefParseXML(virCapsPtr caps def->snapshot = VIR_DOMAIN_DISK_SNAPSHOT_NO; } + def->rawio = -1; /* unspecified */ + if (rawio) { + if (def->device == VIR_DOMAIN_DISK_DEVICE_LUN) { + if (STREQ(rawio, "yes")) { + def->rawio = 1; + } else if (STREQ(rawio, "no")) { + def->rawio = 0; + } else { + virDomainReportError(VIR_ERR_INTERNAL_ERROR, + _("unknown disk rawio setting '%s'"), + rawio); + goto error; + } + } else { + virDomainReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("rawio can be used only with device='lun'")); + goto error; + } + } + if (bus) { if ((def->bus = virDomainDiskBusTypeFromString(bus)) < 0) { virDomainReportError(VIR_ERR_INTERNAL_ERROR, @@ -7517,6 +7541,13 @@ static virDomainDefPtr virDomainDefParse if (!disk) goto error; + /* cap_sys_rawio check */ + if (disk->rawio == 1 && + (def->process_caps & (1ULL << CAP_SYS_RAWIO)) == 0) { + def->process_caps |= (1ULL << CAP_SYS_RAWIO); + VIR_WARN("domain %s will be granted CAP_SYS_RAWIO", def->name); + } + virDomainDiskInsertPreAlloced(def, disk); } VIR_FREE(nodes); @@ -9930,6 +9961,11 @@ virDomainDiskDefFormat(virBufferPtr buf, virBufferAsprintf(buf, " <disk type='%s' device='%s'", type, device); + if (def->rawio == 1) { + virBufferAddLit(buf, " rawio='yes'"); + } else if (def->rawio == 0) { + virBufferAddLit(buf, " rawio='no'"); + } if (def->snapshot && !(def->snapshot == VIR_DOMAIN_DISK_SNAPSHOT_NO && def->readonly)) virBufferAsprintf(buf, " snapshot='%s'", Index: libvirt/src/conf/domain_conf.h =================================================================== --- libvirt.orig/src/conf/domain_conf.h +++ libvirt/src/conf/domain_conf.h @@ -401,6 +401,7 @@ struct _virDomainDiskDef { unsigned int transient : 1; virDomainDeviceInfo info; virStorageEncryptionPtr encryption; + int rawio; /* unspecified:-1 no:0 yes:1 */ }; @@ -1464,6 +1465,8 @@ struct _virDomainDef { char *emulator; int features; + unsigned long long process_caps; + virDomainClockDef clock; int ngraphics; Index: libvirt/docs/formatdomain.html.in =================================================================== --- libvirt.orig/docs/formatdomain.html.in +++ libvirt/docs/formatdomain.html.in @@ -1096,8 +1096,11 @@ - also note that device='lun' will only be recognized for actual raw devices, never for individual partitions or LVM partitions (in those cases, the kernel will reject the generic - SCSI commands, making it identical to device='disk'). The - optional <code>snapshot</code> attribute indicates the default + SCSI commands, making it identical to device='disk'). + The optional <code>rawio</code> attribute indicates that the disk + is desirous of rawio capability. This attribute is only valid when + device is "lun". + The optional <code>snapshot</code> attribute indicates the default behavior of the disk during disk snapshots: "internal" requires a file format such as qcow2 that can store both the snapshot and the data changes since the snapshot;

This patch introduces virKeepCapabilities() function and implements virCommandAllowCap() function. Existing virClearCapabilities() is function to clear all capabilities. Instead virKeepCapabilities() is function to keep arbitrary capabilities. Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com> Signed-off-by: Shota Hirae <m11g1401@hibikino.ne.jp> --- src/util/command.c | 45 ++++++++++++++++++++++++++++++++++++++------- src/util/command.h | 4 +--- 2 files changed, 39 insertions(+), 10 deletions(-) Index: libvirt/src/util/command.c =================================================================== --- libvirt.orig/src/util/command.c +++ libvirt/src/util/command.c @@ -103,6 +103,8 @@ struct _virCommand { pid_t pid; char *pidfile; bool reap; + + unsigned long long capabilities; }; /* @@ -182,6 +184,33 @@ static int virClearCapabilities(void) return 0; } + +/** + * virKeepCapabilities: + * @capabilities - capability flag to keep. + * In case of 0, this function is identical to + * virClearCapabilities() + * + */ +static int virKeepCapabilities(unsigned long long capabilities) +{ + int ret, i; + + capng_clear(CAPNG_SELECT_BOTH); + + for (i = 0; i <= CAP_LAST_CAP; i++) { + if (capabilities & (1ULL << i)) + capng_update(CAPNG_ADD, CAPNG_BOUNDING_SET, i); + } + + if (ret = capng_apply(CAPNG_SELECT_BOTH) < 0) { + virCommandError(VIR_ERR_INTERNAL_ERROR, + _("cannot apply process capabilities %d"), ret); + return -1; + } + + return 0; +} # else static int virClearCapabilities(void) { @@ -189,6 +218,11 @@ static int virClearCapabilities(void) // "capabilities"); return 0; } + +static int virKeepCapabilities(unsigned long long capabilities) +{ + return 0; +} # endif /** @@ -883,26 +917,23 @@ virCommandClearCaps(virCommandPtr cmd) cmd->flags |= VIR_EXEC_CLEAR_CAPS; } -#if 0 /* XXX Enable if we have a need for capability management. */ - /** * virCommandAllowCap: * @cmd: the command to modify - * @capability: what to allow + * @capabilities: what to allow * - * Re-allow a specific capability + * Allow specific capabilities */ void virCommandAllowCap(virCommandPtr cmd, - int capability ATTRIBUTE_UNUSED) + unsigned long long capabilities) { if (!cmd || cmd->has_error) return; - /* XXX ? */ + cmd->capabilities = capabilities; } -#endif /* 0 */ /** Index: libvirt/src/util/command.h =================================================================== --- libvirt.orig/src/util/command.h +++ libvirt/src/util/command.h @@ -60,10 +60,8 @@ void virCommandSetPidFile(virCommandPtr void virCommandClearCaps(virCommandPtr cmd); -# if 0 void virCommandAllowCap(virCommandPtr cmd, - int capability); -# endif + unsigned long long capabilities); void virCommandDaemonize(virCommandPtr cmd);

This patch extends virExecWithHook() to receive capability information. Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com> Signed-off-by: Shota Hirae <m11g1401@hibikino.ne.jp> --- src/util/command.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) Index: libvirt/src/util/command.c =================================================================== --- libvirt.orig/src/util/command.c +++ libvirt/src/util/command.c @@ -393,6 +393,7 @@ prepareStdFd(int fd, int std) * @hook optional virExecHook function to call prior to exec * @data data to pass to the hook function * @pidfile path to use as pidfile for daemonized process (needs DAEMON flag) + * @capabilities capabilities to keep */ static int virExecWithHook(const char *const*argv, @@ -404,7 +405,8 @@ virExecWithHook(const char *const*argv, unsigned int flags, virExecHook hook, void *data, - char *pidfile) + char *pidfile, + unsigned long long capabilities) { pid_t pid; int null = -1, i, openmax; @@ -633,9 +635,9 @@ virExecWithHook(const char *const*argv, /* The steps above may need todo something privileged, so * we delay clearing capabilities until the last minute */ - if ((flags & VIR_EXEC_CLEAR_CAPS) && - virClearCapabilities() < 0) - goto fork_error; + if (capabilities || (flags & VIR_EXEC_CLEAR_CAPS)) + if (virKeepCapabilities(capabilities) < 0) + goto fork_error; /* Close logging again to ensure no FDs leak to child */ virLogReset(); @@ -723,7 +725,8 @@ virExecWithHook(const char *const*argv A int flags_unused ATTRIBUTE_UNUSED, virExecHook hook ATTRIBUTE_UNUSED, void *data ATTRIBUTE_UNUSED, - char *pidfile ATTRIBUTE_UNUSED) + char *pidfile ATTRIBUTE_UNUSED, + unsigned long long capabilities ATTRIBUTE_UNUSED) { /* XXX: Some day we can implement pieces of virCommand/virExec on * top of _spawn() or CreateProcess(), but we can't implement @@ -2171,7 +2174,8 @@ virCommandRunAsync(virCommandPtr cmd, pi cmd->flags, virCommandHook, cmd, - cmd->pidfile); + cmd->pidfile, + cmd->capabilities); VIR_DEBUG("Command result %d, with PID %d", ret, (int)cmd->pid);

This patch revises qemuProcessStart() function for qemu processes to retain arbitrary capabilities. Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com> Signed-off-by: Shota Hirae <m11g1401@hibikino.ne.jp> --- src/qemu/qemu_process.c | 1 + 1 file changed, 1 insertion(+) Index: libvirt/src/qemu/qemu_process.c =================================================================== --- libvirt.orig/src/qemu/qemu_process.c +++ libvirt/src/qemu/qemu_process.c @@ -3334,6 +3334,7 @@ int qemuProcessStart(virConnectPtr conn, driver->clearEmulatorCapabilities); if (driver->clearEmulatorCapabilities) virCommandClearCaps(cmd); + virCommandAllowCap(cmd, vm->def->process_caps); virCommandSetPreExecHook(cmd, qemuProcessHook, &hookData);