[PATCH v3 13/15] qemu: Add support for slices of type 'storage'

Implement support for the slice of type 'storage' which allows to set the offset and size which modifies where qemu should look for the start of the format container inside the image. Since slicing is done using the 'raw' driver we need to add another layer into the blockdev tree if there's any non-raw image format driver used to access the data. This patch adds the blockdev integration and setup of the image data so that we can use the slices for any backing image. Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; --- src/qemu/qemu_block.c | 68 +++++++++++++++++++++++++++++++++++++++- src/qemu/qemu_block.h | 4 +++ src/qemu/qemu_blockjob.c | 1 + src/qemu/qemu_command.c | 8 +++++ src/qemu/qemu_domain.c | 4 +++ 5 files changed, 84 insertions(+), 1 deletion(-) diff --git a/src/qemu/qemu_block.c b/src/qemu/qemu_block.c index 8b94365c68..36b61e5355 100644 --- a/src/qemu/qemu_block.c +++ b/src/qemu/qemu_block.c @@ -1423,11 +1423,16 @@ qemuBlockStorageSourceGetBlockdevProps(virStorageSourcePtr src, virStorageSourcePtr backingStore) { g_autoptr(virJSONValue) props = NULL; + const char *storagenode = src->nodestorage; + + if (src->sliceStorage && + src->format != VIR_STORAGE_FILE_RAW) + storagenode = src->sliceStorage->nodename; if (!(props = qemuBlockStorageSourceGetBlockdevFormatProps(src))) return NULL; - if (virJSONValueObjectAppendString(props, "file", src->nodestorage) < 0) + if (virJSONValueObjectAppendString(props, "file", storagenode) < 0) return NULL; if (backingStore) { @@ -1456,6 +1461,32 @@ qemuBlockStorageSourceGetBlockdevProps(virStorageSourcePtr src, } +static virJSONValuePtr +qemuBlockStorageSourceGetBlockdevStorageSliceProps(virStorageSourcePtr src) +{ + g_autoptr(virJSONValue) props = NULL; + + if (qemuBlockNodeNameValidate(src->sliceStorage->nodename) < 0) + return NULL; + + if (virJSONValueObjectCreate(&props, + "s:driver", "raw", + "s:node-name", src->sliceStorage->nodename, + "U:offset", src->sliceStorage->offset, + "U:size", src->sliceStorage->size, + "s:file", src->nodestorage, + "b:auto-read-only", true, + "s:discard", "unmap", + NULL) < 0) + return NULL; + + if (qemuBlockStorageSourceGetBlockdevGetCacheProps(src, props) < 0) + return NULL; + + return g_steal_pointer(&props); +} + + void qemuBlockStorageSourceAttachDataFree(qemuBlockStorageSourceAttachDataPtr data) { @@ -1463,6 +1494,7 @@ qemuBlockStorageSourceAttachDataFree(qemuBlockStorageSourceAttachDataPtr data) return; virJSONValueFree(data->storageProps); + virJSONValueFree(data->storageSliceProps); virJSONValueFree(data->formatProps); virJSONValueFree(data->prmgrProps); virJSONValueFree(data->authsecretProps); @@ -1513,6 +1545,13 @@ qemuBlockStorageSourceAttachPrepareBlockdev(virStorageSourcePtr src, data->storageNodeName = src->nodestorage; data->formatNodeName = src->nodeformat; + if (src->sliceStorage && src->format != VIR_STORAGE_FILE_RAW) { + if (!(data->storageSliceProps = qemuBlockStorageSourceGetBlockdevStorageSliceProps(src))) + return NULL; + + data->storageSliceNodeName = src->sliceStorage->nodename; + } + return g_steal_pointer(&data); } @@ -1581,6 +1620,21 @@ qemuBlockStorageSourceAttachApplyFormat(qemuMonitorPtr mon, } +static int +qemuBlockStorageSourceAttachApplyStorageSlice(qemuMonitorPtr mon, + qemuBlockStorageSourceAttachDataPtr data) +{ + if (data->storageSliceProps) { + if (qemuMonitorBlockdevAdd(mon, &data->storageSliceProps) < 0) + return -1; + + data->storageSliceAttached = true; + } + + return 0; +} + + /** * qemuBlockStorageSourceAttachApply: * @mon: monitor object @@ -1600,6 +1654,7 @@ qemuBlockStorageSourceAttachApply(qemuMonitorPtr mon, { if (qemuBlockStorageSourceAttachApplyStorageDeps(mon, data) < 0 || qemuBlockStorageSourceAttachApplyStorage(mon, data) < 0 || + qemuBlockStorageSourceAttachApplyStorageSlice(mon, data) < 0 || qemuBlockStorageSourceAttachApplyFormatDeps(mon, data) < 0 || qemuBlockStorageSourceAttachApplyFormat(mon, data) < 0) return -1; @@ -1642,6 +1697,9 @@ qemuBlockStorageSourceAttachRollback(qemuMonitorPtr mon, if (data->formatAttached) ignore_value(qemuMonitorBlockdevDel(mon, data->formatNodeName)); + if (data->storageSliceAttached) + ignore_value(qemuMonitorBlockdevDel(mon, data->storageSliceNodeName)); + if (data->storageAttached) ignore_value(qemuMonitorBlockdevDel(mon, data->storageNodeName)); @@ -1689,6 +1747,14 @@ qemuBlockStorageSourceDetachPrepare(virStorageSourcePtr src, data->formatAttached = true; data->storageNodeName = src->nodestorage; data->storageAttached = true; + + /* 'raw' format doesn't need the extra 'raw' layer when slicing, thus + * the nodename is NULL */ + if (src->sliceStorage && + src->sliceStorage->nodename) { + data->storageSliceNodeName = src->sliceStorage->nodename; + data->storageSliceAttached = true; + } } if (src->pr && diff --git a/src/qemu/qemu_block.h b/src/qemu/qemu_block.h index a816190bb7..eab0128d5d 100644 --- a/src/qemu/qemu_block.h +++ b/src/qemu/qemu_block.h @@ -82,6 +82,10 @@ struct qemuBlockStorageSourceAttachData { const char *storageNodeName; bool storageAttached; + virJSONValuePtr storageSliceProps; + const char *storageSliceNodeName; + bool storageSliceAttached; + virJSONValuePtr formatProps; const char *formatNodeName; bool formatAttached; diff --git a/src/qemu/qemu_blockjob.c b/src/qemu/qemu_blockjob.c index 6b59bbeb2c..71df0d1ab2 100644 --- a/src/qemu/qemu_blockjob.c +++ b/src/qemu/qemu_blockjob.c @@ -1316,6 +1316,7 @@ qemuBlockJobProcessEventConcludedCreate(virQEMUDriverPtr driver, backend->formatAttached = false; if (job->data.create.storage) { backend->storageAttached = false; + backend->storageSliceAttached = false; VIR_FREE(backend->encryptsecretAlias); } diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 0dbd78124b..6c26e7bb7d 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -2411,6 +2411,14 @@ qemuBuildBlockStorageSourceAttachDataCommandline(virCommandPtr cmd, VIR_FREE(tmp); } + if (data->storageSliceProps) { + if (!(tmp = virJSONValueToString(data->storageSliceProps, false))) + return -1; + + virCommandAddArgList(cmd, "-blockdev", tmp, NULL); + VIR_FREE(tmp); + } + if (data->formatProps) { if (!(tmp = virJSONValueToString(data->formatProps, false))) return -1; diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index 534a91cf82..f8d034c382 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -16224,6 +16224,10 @@ qemuDomainPrepareStorageSourceBlockdev(virDomainDiskDefPtr disk, src->nodestorage = g_strdup_printf("libvirt-%u-storage", src->id); src->nodeformat = g_strdup_printf("libvirt-%u-format", src->id); + if (src->sliceStorage && + src->format != VIR_STORAGE_FILE_RAW) + src->sliceStorage->nodename = g_strdup_printf("libvirt-%u-slice-sto", src->id); + if (qemuDomainValidateStorageSource(src, priv->qemuCaps) < 0) return -1; -- 2.24.1