md/raid1,raid10: don't ignore IO flags

commit e879a0d9cb086c8e52ce6c04e5bfa63825a6213c upstream.

If blk-wbt is enabled by default, it's found that raid write performance
is quite bad because all IO are throttled by wbt of underlying disks,
due to flag REQ_IDLE is ignored. And turns out this behaviour exist since
blk-wbt is introduced.

Other than REQ_IDLE, other flags should not be ignored as well, for
example REQ_META can be set for filesystems, clearing it can cause priority
reverse problems; And REQ_NOWAIT should not be cleared as well, because
io will wait instead of failing directly in underlying disks.

Fix those problems by keep IO flags from master bio.

BUG=b/444178455
TEST=presubmit
RELEASE_NOTE=Fixed CVE-2025-22125 in the Linux kernel.

cos-patch: security-moderate
Fises: f51d46d0e7cb ("md: add support for REQ_NOWAIT")
Fixes: e34cbd307477 ("blk-wbt: add general throttling mechanism")
Fixes: 5404bc7a87b9 ("[PATCH] Allow file systems to differentiate between data and meta reads")
Link: https://lore.kernel.org/linux-raid/20250227121657.832356-1-yukuai1@huaweicloud.com
Change-Id: I17285663049d7e26374615d254ff9ce7ec0a6ab3
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
[ Harshit: Resolve conflicts due to missing commit: f2a38abf5f1c
  ("md/raid1: Atomic write support") and  commit: a1d9b4fd42d9
  ("md/raid10: Atomic write support") in 6.12.y, we don't have Atomic
  writes feature in 6.12.y ]
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Based on Harshit's backport for 6.12, fixed minor conflicts for 6.6. ]
Signed-off-by: Charles Xu <charles_xu@189.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kernel CVE Triage Automation <cloud-image-kernel-cve-triage-automation@prod.google.com>
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/148023
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: Angel Adetula <angeladetula@google.com>
Reviewed-by: Robert Kolchmeyer <rkolchmeyer@google.com>