AtaBusDxe: Fix ReadBlockEx andWriteBlockEx to still signal event when the BufferSize is 0.
DiskIoDxe: Fix ReadDiskEx and WriteDiskEx to not modify the user’s buffer when the BufferSize is 0.
DiskIoDxe: Fix ReadDiskEx and WriteDiskEx hang issue when the submitted blockio2 task is completed before submitting another blockio2 task.
DiskIoDxe: Fix FlushEx to free the flush task item in callback (memory leak issue).

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16215 6f19259b-4bc3-4df7-8a09-765794883524
Prevent EBDA area being overwritten, get the size info from the address 0x40E. If can’t get the size info, then use the default value for it.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>


git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16216 6f19259b-4bc3-4df7-8a09-765794883524
Add comments for FSVariable driver which used by Duet platform only, trust all meta data for this platform.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>


git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16217 6f19259b-4bc3-4df7-8a09-765794883524
Add comments for FSVariable driver which used by Duet platform only, trust all meta data for this platform.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16218 6f19259b-4bc3-4df7-8a09-765794883524
Merge branch 'master' of https://github.com/tianocore/edk2