Add new API virDomain{Set, Get}BlockIoTune

This patch add new pulic API virDomainSetBlockIoTune and
virDomainGetBlockIoTune.

Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: Eric Blake <eblake@redhat.com>

include/libvirt/libvirt.h.in

@@ -1700,6 +1700,69 @@ int           virDomainBlockPull(virDomainPtr dom, const char *disk,
                                  unsigned long bandwidth, unsigned int flags);
 
 
+/* Block I/O throttling support */
+
+/**
+ * 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"
+
+/**
+ * VIR_DOMAIN_BLOCK_IOTUNE_READ_BYTES_SEC:
+ *
+ * Macro for the BlockIoTune tunable weight: it repersents the read
+ * bytes per second permitted through a block device, as a ullong.
+ */
+#define VIR_DOMAIN_BLOCK_IOTUNE_READ_BYTES_SEC "read_bytes_sec"
+
+/**
+ * VIR_DOMAIN_BLOCK_IOTUNE_WRITE_BYTES_SEC:
+ *
+ * Macro for the BlockIoTune tunable weight: it repersents the write
+ * bytes per second permitted through a block device, as a ullong.
+ */
+#define VIR_DOMAIN_BLOCK_IOTUNE_WRITE_BYTES_SEC "write_bytes_sec"
+
+/**
+ * VIR_DOMAIN_BLOCK_IOTUNE_TOTAL_IOPS_SEC:
+ *
+ * Macro for the BlockIoTune tunable weight: it repersents the total
+ * I/O operations per second permitted through a block device, as a ullong.
+ */
+#define VIR_DOMAIN_BLOCK_IOTUNE_TOTAL_IOPS_SEC "total_iops_sec"
+
+/**
+ * VIR_DOMAIN_BLOCK_IOTUNE_READ_IOPS_SEC:
+ *
+ * Macro for the BlockIoTune tunable weight: it repersents the read
+ * I/O operations per second permitted through a block device, as a ullong.
+ */
+#define VIR_DOMAIN_BLOCK_IOTUNE_READ_IOPS_SEC "read_iops_sec"
+
+/**
+ * VIR_DOMAIN_BLOCK_IOTUNE_WRITE_IOPS_SEC:
+ * Macro for the BlockIoTune tunable weight: it repersents the write
+ * I/O operations per second permitted through a block device, as a ullong.
+ */
+#define VIR_DOMAIN_BLOCK_IOTUNE_WRITE_IOPS_SEC "write_iops_sec"
+
+int
+virDomainSetBlockIoTune(virDomainPtr dom,
+                        const char *disk,
+                        virTypedParameterPtr params,
+                        int nparams,
+                        unsigned int flags);
+int
+virDomainGetBlockIoTune(virDomainPtr dom,
+                        const char *disk,
+                        virTypedParameterPtr params,
+                        int *nparams,
+                        unsigned int flags);
+
+
 /*
  * NUMA support
  */

python/generator.py

@@ -470,6 +470,9 @@ skip_function = (
     "virNWFilterGetConnect",
     "virStoragePoolGetConnect",
     "virStorageVolGetConnect",
+
+    "virDomainGetBlockIoTune", # not implemented yet
+    "virDomainSetBlockIoTune", # not implemented yet
 )
 
 qemu_skip_function = (

src/driver.h

@@ -757,6 +757,19 @@ typedef int
                           int interval,
                           unsigned int count);
 
+typedef int
+    (*virDrvDomainSetBlockIoTune)(virDomainPtr dom,
+                                  const char *disk,
+                                  virTypedParameterPtr params,
+                                  int nparams,
+                                  unsigned int flags);
+typedef int
+    (*virDrvDomainGetBlockIoTune)(virDomainPtr dom,
+                                  const char *disk,
+                                  virTypedParameterPtr params,
+                                  int *nparams,
+                                  unsigned int flags);
+
 /**
  * _virDriver:
  *
@@ -919,6 +932,8 @@ struct _virDriver {
     virDrvSetKeepAlive setKeepAlive;
     virDrvConnectIsAlive isAlive;
     virDrvNodeSuspendForDuration nodeSuspendForDuration;
+    virDrvDomainSetBlockIoTune domainSetBlockIoTune;
+    virDrvDomainGetBlockIoTune domainGetBlockIoTune;
 };
 
 typedef int

src/libvirt.c

@@ -17441,3 +17441,158 @@ error:
     virDispatchError(conn);
     return -1;
 }
+
+
+/**
+ * virDomainSetBlockIoTune:
+ * @dom: pointer to domain object
+ * @disk: path to the block device, or device shorthand
+ * @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
+ *
+ * Change all or a subset of the per-device block IO tunables.
+ *
+ * The @disk parameter is either an unambiguous source name of the
+ * block device (the <source file='...'/> sub-element, such as
+ * "/path/to/image"), or the device target shorthand (the <target
+ * dev='...'/> sub-element, such as "xvda").  Valid names can be found
+ * by calling virDomainGetXMLDesc() and inspecting elements
+ * within //domain/devices/disk.
+ *
+ * Returns -1 in case of error, 0 in case of success.
+ */
+int virDomainSetBlockIoTune(virDomainPtr dom,
+                            const char *disk,
+                            virTypedParameterPtr params,
+                            int nparams,
+                            unsigned int flags)
+{
+    virConnectPtr conn;
+
+    VIR_DOMAIN_DEBUG(dom, "disk=%p, params=%p, nparams=%d, flags=%x",
+                     disk, params, nparams, flags);
+
+    virResetLastError();
+
+    if (!VIR_IS_CONNECTED_DOMAIN(dom)) {
+        virLibDomainError(VIR_ERR_INVALID_DOMAIN, __FUNCTION__);
+        virDispatchError(NULL);
+        return -1;
+    }
+
+    if (dom->conn->flags & VIR_CONNECT_RO) {
+        virLibDomainError(VIR_ERR_OPERATION_DENIED, __FUNCTION__);
+        goto error;
+    }
+
+    if (!disk || (nparams <= 0) || (params == NULL)) {
+        virLibDomainError(VIR_ERR_INVALID_ARG, __FUNCTION__);
+        goto error;
+    }
+
+    if (virTypedParameterValidateSet(dom, params, nparams) < 0)
+        return -1;
+
+    conn = dom->conn;
+
+    if (conn->driver->domainSetBlockIoTune) {
+        int ret;
+        ret = conn->driver->domainSetBlockIoTune(dom, disk, params, nparams, flags);
+        if (ret < 0)
+            goto error;
+        return ret;
+    }
+
+    virLibDomainError(VIR_ERR_NO_SUPPORT, __FUNCTION__);
+
+error:
+    virDispatchError(dom->conn);
+    return -1;
+}
+
+/**
+ * virDomainGetBlockIoTune:
+ * @dom: pointer to domain object
+ * @disk: path to the block device, or device shorthand
+ * @params: Pointer to blkio parameter object
+ *          (return value, allocated by the caller)
+ * @nparams: Pointer to number of blkio parameters
+ * @flags: An OR'ed set of virDomainModificationImpact
+ *
+ * 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.
+ *
+ * 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, either for the given @disk
+ * (note that block devices of different types might support different
+ * parameters), or if @disk is NULL, for all possible disks. The
+ * caller should then allocate @params array,
+ * i.e. (sizeof(@virTypedParameter) * @nparams) bytes and call the API
+ * again.  See virDomainGetMemoryParameters() for more details.
+ *
+ * The @disk parameter is either an unambiguous source name of the
+ * block device (the <source file='...'/> sub-element, such as
+ * "/path/to/image"), or the device target shorthand (the <target
+ * dev='...'/> sub-element, such as "xvda").  Valid names can be found
+ * by calling virDomainGetXMLDesc() and inspecting elements
+ * within //domain/devices/disk.  This parameter cannot be NULL
+ * unless @nparams is 0 on input.
+ *
+ * Returns -1 in case of error, 0 in case of success.
+ */
+int virDomainGetBlockIoTune(virDomainPtr dom,
+                            const char *disk,
+                            virTypedParameterPtr params,
+                            int *nparams,
+                            unsigned int flags)
+{
+    virConnectPtr conn;
+
+    VIR_DOMAIN_DEBUG(dom, "disk=%p, params=%p, nparams=%d, flags=%x",
+                     NULLSTR(disk), params, (nparams) ? *nparams : -1, flags);
+
+    virResetLastError();
+
+    if (!VIR_IS_CONNECTED_DOMAIN (dom)) {
+        virLibDomainError(VIR_ERR_INVALID_DOMAIN, __FUNCTION__);
+        virDispatchError(NULL);
+        return -1;
+    }
+
+    if (nparams == NULL || *nparams < 0 ||
+        ((params == NULL || disk == NULL) && *nparams != 0)) {
+        virLibDomainError(VIR_ERR_INVALID_ARG, __FUNCTION__);
+        goto error;
+    }
+
+    if (VIR_DRV_SUPPORTS_FEATURE(dom->conn->driver, dom->conn,
+                                 VIR_DRV_FEATURE_TYPED_PARAM_STRING))
+        flags |= VIR_TYPED_PARAM_STRING_OKAY;
+
+    /* At most one of these two flags should be set.  */
+    if ((flags & VIR_DOMAIN_AFFECT_LIVE) &&
+        (flags & VIR_DOMAIN_AFFECT_CONFIG)) {
+        virLibDomainError(VIR_ERR_INVALID_ARG, __FUNCTION__);
+        goto error;
+    }
+    conn = dom->conn;
+
+    if (conn->driver->domainGetBlockIoTune) {
+        int ret;
+        ret = conn->driver->domainGetBlockIoTune(dom, disk, params, nparams, flags);
+        if (ret < 0)
+            goto error;
+        return ret;
+    }
+
+    virLibDomainError(VIR_ERR_NO_SUPPORT, __FUNCTION__);
+
+error:
+    virDispatchError(dom->conn);
+    return -1;
+}

src/libvirt_public.syms

@@ -502,8 +502,10 @@ LIBVIRT_0.9.8 {
     global:
         virConnectIsAlive;
         virConnectSetKeepAlive;
-        virNodeSuspendForDuration;
         virDomainBlockResize;
+        virDomainGetBlockIoTune;
+        virDomainSetBlockIoTune;
+        virNodeSuspendForDuration;
 } LIBVIRT_0.9.7;
 
 # .... define new API here using predicted next version number ....