<fix>[storage]: support ceph multi image cache pools

[ZStack-Robot]

PROBLEM:
Ceph primary storage previously assumed one image cache pool for one primary storage. When a VM root volume is created on another pool, the root volume may be cloned from the image cache snapshot in the default pool. Some customer Ceph clusters do not support cross-pool RBD clone, so VM creation, reimage, and change image can fail when the selected volume pool differs from the image cache pool.

SOLUTION:
Add a Ceph image cache pool strategy. The default strategy keeps the old behavior and uses the default image cache pool. The volume-pool strategy selects the target root volume pool when that physical pool also has the ImageCache role. Otherwise it falls back to the default image cache pool. The existing-cache strategy reuses an existing cache first, preferring the default pool cache and then another valid cache record.

Image cache preparation now selects the target cache pool before capacity allocation. If the selected pool already has a valid cache snapshot, the existing cache is reused. If the selected cache record is stale, only that cache record and its refs are removed and the flow retries. If another pool has a valid cache for the same image, the snapshot is copied into the selected pool with RBD cp/deep cp. The normal create-snapshot and protect-snapshot flow then creates a new cache in the selected pool. If no usable cache exists, the image is downloaded through the existing backup storage flow. Same-Ceph backup storage is copied into the selected pool when needed to avoid later cross-pool clone.

The final root volume operation still clones from the prepared image cache snapshot. The data-copy step is only used to materialize the cache in the selected pool. Snapshot reuse images keep their original volumeSnapshotReuse cache record and do not fall back to ordinary backup-storage download. Reinit can still select existing cache records by image UUID when the source ImageVO has already been deleted.

TEST:
Verified on root@172.20.13.237 under /root/zstack-workspace/zstack. Ran the changed Ceph integration case through TestCaseStabilityTest: CephPrimaryStorageVolumePoolsCase. Result: BUILD SUCCESS. Tests run: 1, Failures: 0, Errors: 0.

The case covers default strategy compatibility, volume-pool strategy, existing-cache strategy, same-Ceph backup storage copy to selected pool, stale selected cache cleanup, copying cache from another pool, image cache cleanup with refs, reimage, and multi-ImageCache-pool setup in the common Ceph primary storage spec.

Resolves: ZSTAC-62608

Change-Id: Ie498c8af87c1a0248429cc81980b135725894778

sync from gitlab !10411

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Review details

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Configuration used: Repository UI

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Run ID: ebd4e3a7-8bf4-4499-af51-5fe6f383df62

📥 Commits

Reviewing files that changed from the base of the PR and between 2f71ae4 and f131bc6.

⛔ Files ignored due to path filters (1)

• conf/globalConfig/ceph.xml is excluded by !**/*.xml

📒 Files selected for processing (14)

• conf/db/upgrade/V4.8.38-Elitery__schema.sql
• header/src/main/java/org/zstack/header/storage/primary/DownloadVolumeTemplateToPrimaryStorageMsg.java
• plugin/ceph/src/main/java/org/zstack/storage/ceph/CephGlobalConfig.java
• plugin/ceph/src/main/java/org/zstack/storage/ceph/primary/APIAddCephPrimaryStoragePoolMsg.java
• plugin/ceph/src/main/java/org/zstack/storage/ceph/primary/CephImageCachePoolStrategy.java
• plugin/ceph/src/main/java/org/zstack/storage/ceph/primary/CephPrimaryStorageBase.java
• sdk/src/main/java/org/zstack/sdk/AddCephPrimaryStoragePoolAction.java
• test/src/test/groovy/org/zstack/test/integration/storage/ceph/CephOperationCase.groovy
• test/src/test/groovy/org/zstack/test/integration/storage/primary/ceph/CephPrimaryStorageVolumePoolsCase.groovy
• test/src/test/groovy/org/zstack/test/integration/storage/primary/ceph/capacity/CephOpenSourcePoolCapacityCase.groovy
• test/src/test/groovy/org/zstack/test/integration/storage/primary/ceph/sandstone/capacity/CephSandStonePoolCapacityCase.groovy
• test/src/test/groovy/org/zstack/test/integration/storage/primary/ceph/xsky/capacity/CephXskyPoolCapacityCase.groovy
• testlib/src/main/java/org/zstack/testlib/CephPrimaryStoragePoolSpec.groovy
• testlib/src/main/java/org/zstack/testlib/CephPrimaryStorageSpec.groovy

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch sync/shan.wu/cherry-pick-multi-imagecache-pool@@3

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