On 11/10/2011 03:04 PM, Eric Blake wrote:
We still need a v4 respinning this to use virTypedParameter; I can help by posting a patch 1/8 that shows the changes that I think we need in the public interface, but I don't want to spend the time rebasing the entire series.
This is more along the lines of what I'm looking for in patch 1/8 (as a diff against your v3 attempt at 1/8). Obviously, it doesn't compile as is, so much as focus on the public interface aspect: diff --git i/include/libvirt/libvirt.h.in w/include/libvirt/libvirt.h.in index 4b05869..52ae0ab 100644 --- i/include/libvirt/libvirt.h.in +++ w/include/libvirt/libvirt.h.in @@ -1684,26 +1684,27 @@ int virDomainBlockPull(virDomainPtr dom, const char *path, * Block I/O throttling support */ -typedef struct _virDomainBlockIoTuneInfo virDomainBlockIoTuneInfo; -struct _virDomainBlockIoTuneInfo { - unsigned long long total_bytes_sec; - unsigned long long read_bytes_sec; - unsigned long long write_bytes_sec; - unsigned long long total_iops_sec; - unsigned long long read_iops_sec; - unsigned long long write_iops_sec; -}; -typedef virDomainBlockIoTuneInfo *virDomainBlockIoTuneInfoPtr; +/** + * VIR_DOMAIN_BLOCK_IOTUNE_TOTAL_BYTES_SEC: + * + * Macro for the BlockIoTune tunable weight: it represents the total + * bytes per second permitted through a block device, as a ullong. + */ +#define VIR_DOMAIN_BLOCK_IOTUNE_TOTAL_BYTES_SEC "total_bytes_sec" + +/* ... and so forth - 6 macros total */ int virDomainSetBlockIoTune(virDomainPtr dom, const char *disk, - virDomainBlockIoTuneInfoPtr info, + virTypedParameterPtr params, + int nparams, unsigned int flags); int virDomainGetBlockIoTune(virDomainPtr dom, const char *disk, - virDomainBlockIoTuneInfoPtr reply, + virTypedParameterPtr params, + int *nparams, unsigned int flags); diff --git i/src/libvirt.c w/src/libvirt.c index cd5931f..287dfc5 100644 --- i/src/libvirt.c +++ w/src/libvirt.c @@ -17184,17 +17184,23 @@ error: * virDomainSetBlockIoTune: * @dom: pointer to domain object * @disk: Fully-qualified disk name - * @info: Specify block I/O limits in bytes + * @params: pointer to blkio parameter objects + * @nparams: number of blkio parameters (this value can be the same or + * less than the number of parameters supported) * @flags: An OR'ed set of virDomainModificationImpact * - * This function is mainly to enable Block I/O throttling function in libvirt. - * It is used to change the block I/O throttling setting for specified domain. + * Change all or a subset of the per-device block IO tunables. * - * Returns 0 if the operation has started, -1 on failure. + * The @disk parameter is the name of the block device. Get this + * by calling virDomainGetXMLDesc and finding the <target dev='...'> + * attribute within //domain/devices/disk. (For example, "xvda"). + * + * Returns -1 in case of error, 0 in case of success. */ int virDomainSetBlockIoTune(virDomainPtr dom, const char *disk, - virDomainBlockIoTuneInfoPtr info, + virTypedParameterPtr params, + int nparams, unsigned int flags) { virConnectPtr conn; @@ -17245,18 +17251,35 @@ error: * virDomainGetBlockIoTune: * @dom: pointer to domain object * @disk: Fully-qualified disk name - * @reply: Specify block I/O info in bytes + * @params: pointer to blkio parameter object + * (return value, allocated by the caller) + * @nparams: pointer to number of blkio parameters; input and output * @flags: An OR'ed set of virDomainModificationImpact * - * This function is mainly to enable Block I/O throttling function in libvirt. - * It is used to get the block I/O throttling setting for specified domain. + * Get all block IO tunable parameters for a given device. On input, + * @nparams gives the size of the @params array; on output, @nparams + * gives how many slots were filled with parameter information, which + * might be less but will not exceed the input value. * - * Returns 0 if the operation has started, -1 on failure. + * As a special case, calling with @params as NULL and @nparams as 0 on + * input will cause @nparams on output to contain the number of parameters + * supported by the hypervisor. The caller should then allocate @params + * array, i.e. (sizeof(@virTypedParameter) * @nparams) bytes and call the API + * again. + * + * See virDomainGetMemoryParameters() for an equivalent usage example. + * + * The @disk parameter is the name of the block device. Get this + * by calling virDomainGetXMLDesc and finding the <target dev='...'> + * attribute within //domain/devices/disk. (For example, "xvda"). + * + * Returns -1 in case of error, 0 in case of success. */ int virDomainGetBlockIoTune(virDomainPtr dom, const char *disk, - virDomainBlockIoTuneInfoPtr reply, + virTypedParameterPtr params, + int *nparams, unsigned int flags) { virConnectPtr conn; -- Eric Blake eblake@redhat.com +1-801-349-2682 Libvirt virtualization library http://libvirt.org