[CHERRY-PICK] FatPkg: Clean any volume caches during exit boot services#1832
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os-d
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nit: We've been doing git cherry-pick -x to get the cherry-picked commit hash in the commit message for easy reference.
makubacki
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The current implementation assumes the the caller will perform the necessary cleanup before exiting boot services. This has been observed to drop some cached file writes that occur even before the application calling exit boot services is launched. This commit adds a per-volume pre-ExitBootServices event to flush any dirty caches and perform other cleanup the volume to ensure all write data is persisted and consistent. After the flush, caching will be disabled for the volume in the future to ensure that all subsequent access persists. Signed-off-by: Chris Fernald <chfernal@microsoft.com> (cherry picked from commit 12c5ded287fc142380b0f9efab3b6ac47c2d1067)
apop5
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Description
The current implementation assumes the the caller will perform the necessary cleanup before exiting boot services. This has been observed to drop some cached file writes that occur even before the application calling exit boot services is launched.
This commit adds a per-volume pre-ExitBootServices event to flush any dirty caches and perform other cleanup the volume to ensure all write data is persisted and consistent. After the flush, caching will be disabled for the volume in the future to ensure that all subsequent access persists.
How This Was Tested
Tested on QEMU with one-off shell test and boot to OS
Integration Instructions
N/A