Re: [libvirt] [PATCH libvirt] storage: learn to create qcow2 with preallocation

Use preallocation mode specified in volume XML format when running qemu-img. --- src/storage/storage_backend.c | 70 +++++++++++++++++++++++++++++++++++------ 1 file changed, 60 insertions(+), 10 deletions(-) diff --git a/src/storage/storage_backend.c b/src/storage/storage_backend.c index caac2f8..523b6e2 100644 --- a/src/storage/storage_backend.c +++ b/src/storage/storage_backend.c @@ -645,6 +645,38 @@ cleanup: return ret; } +static char * +virStorageQemuImgOptionsStr(virStorageVolDefPtr vol) +{ + virBuffer buf = VIR_BUFFER_INITIALIZER; + bool do_encryption = (vol->target.encryption != NULL); + const char *backingType = vol->backingStore.path ? + virStorageFileFormatTypeToString(vol->backingStore.format) : NULL; + bool comma = false; + const char *preallocation = vol->preallocation != VIR_STORAGE_PREALLOCATION_NONE ? + virStoragePreallocationModeTypeToString(vol->preallocation) : NULL; + + if (backingType) { + virBufferAddLit(&buf, "backing_fmt="); + virBufferAdd(&buf, backingType, -1); + comma = true; + } + + if (do_encryption) { + virBufferAdd(&buf, comma ? "," : "", -1); + virBufferAddLit(&buf, "encryption=on"); + comma = true; + } + + if (preallocation) { + virBufferAdd(&buf, comma ? "," : "", -1); + virBufferAddLit(&buf, "preallocation="); + virBufferAdd(&buf, preallocation, -1); + comma = true; + } + + return virBufferContentAndReset(&buf); +} static int virStorageBackendCreateQemuImg(virConnectPtr conn, @@ -658,7 +690,9 @@ virStorageBackendCreateQemuImg(virConnectPtr conn, int imgformat = -1; virCommandPtr cmd = NULL; bool do_encryption = (vol->target.encryption != NULL); + bool with_preallocation = (vol->preallocation != VIR_STORAGE_PREALLOCATION_NONE); unsigned long long int size_arg; + char *options; virCheckFlags(0, -1); @@ -689,6 +723,12 @@ virStorageBackendCreateQemuImg(virConnectPtr conn, return -1; } + if (vol->target.format != VIR_STORAGE_FILE_QCOW2 && with_preallocation) { + virStorageReportError(VIR_ERR_CONFIG_UNSUPPORTED, + _("Preallocation is only available with qcow2")); + return -1; + } + if (vol->backingStore.path) { int accessRetCode = -1; char *absolutePath = NULL; @@ -781,16 +821,22 @@ virStorageBackendCreateQemuImg(virConnectPtr conn, if (imgformat < 0) goto cleanup; + if (imgformat != QEMU_IMG_BACKING_FORMAT_OPTIONS && with_preallocation) + VIR_INFO("Preallocation not supported with this version of qemu-img"); + cmd = virCommandNew(create_tool); if (inputvol) { virCommandAddArgList(cmd, "convert", "-f", inputType, "-O", type, inputPath, vol->target.path, NULL); - if (do_encryption) { - if (imgformat == QEMU_IMG_BACKING_FORMAT_OPTIONS) { - virCommandAddArgList(cmd, "-o", "encryption=on", NULL); - } else { + if (imgformat == QEMU_IMG_BACKING_FORMAT_OPTIONS) { + virCommandAddArg(cmd, "-o"); + options = virStorageQemuImgOptionsStr(vol); + virCommandAddArg(cmd, options); + VIR_FREE(options); + } else { + if (do_encryption) { virCommandAddArg(cmd, "-e"); } } @@ -811,10 +857,11 @@ virStorageBackendCreateQemuImg(virConnectPtr conn, case QEMU_IMG_BACKING_FORMAT_OPTIONS: virCommandAddArg(cmd, "-o"); - virCommandAddArgFormat(cmd, "backing_fmt=%s%s", backingType, - do_encryption ? ",encryption=on" : ""); + options = virStorageQemuImgOptionsStr(vol); + virCommandAddArg(cmd, options); virCommandAddArg(cmd, vol->target.path); virCommandAddArgFormat(cmd, "%lluK", size_arg); + VIR_FREE(options); break; default: @@ -831,10 +878,13 @@ virStorageBackendCreateQemuImg(virConnectPtr conn, vol->target.path, NULL); virCommandAddArgFormat(cmd, "%lluK", size_arg); - if (do_encryption) { - if (imgformat == QEMU_IMG_BACKING_FORMAT_OPTIONS) { - virCommandAddArgList(cmd, "-o", "encryption=on", NULL); - } else { + if (imgformat == QEMU_IMG_BACKING_FORMAT_OPTIONS) { + virCommandAddArg(cmd, "-o"); + options = virStorageQemuImgOptionsStr(vol); + virCommandAddArg(cmd, options); + VIR_FREE(options); + } else { + if (do_encryption) { virCommandAddArg(cmd, "-e"); } } -- 1.7.10.1 -- libvir-list mailing list libvir-list(a)redhat.com https://www.redhat.com/mailman/listinfo/libvir-list