22 lines
1001 B
Markdown
22 lines
1001 B
Markdown
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# iSCSI Hotplug {#iscsi_hotplug}
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At the iSCSI level, we provide the following support for Hotplug:
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1. bdev/nvme:
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At the bdev/nvme level, we start one hotplug monitor which will call
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spdk_nvme_probe() periodically to get the hotplug events. We provide the
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private attach_cb and remove_cb for spdk_nvme_probe(). For the attach_cb,
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we will create the block device base on the NVMe device attached, and for the
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remove_cb, we will unregister the block device, which will also notify the
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upper level stack (for iSCSI target, the upper level stack is scsi/lun) to
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handle the hot-remove event.
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2. scsi/lun:
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When the LUN receive the hot-remove notification from block device layer,
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the LUN will be marked as removed, and all the IOs after this point will
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return with check condition status. Then the LUN starts one poller which will
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wait for all the commands which have already been submitted to block device to
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return back; after all the commands return back, the LUN will be deleted.
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@sa spdk_nvme_probe
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