mirror of https://github.com/xemu-project/xemu.git
1604c04931
scsi_device_for_each_req_async() currently does not provide any way to be awaited. One of its callers is scsi_device_purge_requests(), which therefore currently does not guarantee that all requests are fully settled when it returns. We want all requests to be settled, because scsi_device_purge_requests() is called through the unrealize path, including the one invoked by virtio_scsi_hotunplug() through qdev_simple_device_unplug_cb(), which most likely assumes that all SCSI requests are done then. In fact, scsi_device_purge_requests() already contains a blk_drain(), but this will not fully await scsi_device_for_each_req_async(), only the I/O requests it potentially cancels (not the non-I/O requests). However, we can have scsi_device_for_each_req_async() increment the BB in-flight counter, and have scsi_device_for_each_req_async_bh() decrement it when it is done. This way, the blk_drain() will fully await all SCSI requests to be purged. This also removes the need for scsi_device_for_each_req_async_bh() to double-check the current context and potentially re-schedule itself, should it now differ from the BB's context: Changing a BB's AioContext with a root node is done through bdrv_try_change_aio_context(), which creates a drained section. With this patch, we keep the BB in-flight counter elevated throughout, so we know the BB's context cannot change. Signed-off-by: Hanna Czenczek <hreitz@redhat.com> Message-ID: <20240202144755.671354-3-hreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> |
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| .. | ||
| Kconfig | ||
| emulation.c | ||
| esp-pci.c | ||
| esp.c | ||
| lsi53c895a.c | ||
| megasas.c | ||
| meson.build | ||
| mfi.h | ||
| mpi.h | ||
| mptconfig.c | ||
| mptendian.c | ||
| mptsas.c | ||
| mptsas.h | ||
| scsi-bus.c | ||
| scsi-disk.c | ||
| scsi-generic.c | ||
| spapr_vscsi.c | ||
| srp.h | ||
| trace-events | ||
| trace.h | ||
| vhost-scsi-common.c | ||
| vhost-scsi.c | ||
| vhost-user-scsi.c | ||
| viosrp.h | ||
| virtio-scsi-dataplane.c | ||
| virtio-scsi.c | ||
| vmw_pvscsi.c | ||
| vmw_pvscsi.h | ||