[ Upstream commit dad8261e643849ea134c7cd5c8e794e31d93b9eb ]

The return value is taken to mean "retry" or "don't retry". Change it to bool
to improve readability. Fix related comments. No functional change.
Tested-by: NMichael Schmitz <schmitzmic@gmail.com>
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>