2021-07-07 05:30:49

by Satya Tangirala

[permalink] [raw]
Subject: [PATCH v4 5/9] ufshcd: handle error from blk_ksm_register()

From: Satya Tangirala <[email protected]>

Handle any error from blk_ksm_register() in the callers. Previously,
the callers ignored the return value because blk_ksm_register() wouldn't
fail as long as the request_queue didn't have integrity support too, but
as this is no longer the case, it's safer for the callers to just handle
the return value appropriately.

Signed-off-by: Satya Tangirala <[email protected]>
---
drivers/scsi/ufs/ufshcd-crypto.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd-crypto.c b/drivers/scsi/ufs/ufshcd-crypto.c
index d70cdcd35e43..0fcf9d6752f8 100644
--- a/drivers/scsi/ufs/ufshcd-crypto.c
+++ b/drivers/scsi/ufs/ufshcd-crypto.c
@@ -233,6 +233,15 @@ void ufshcd_init_crypto(struct ufs_hba *hba)
void ufshcd_crypto_setup_rq_keyslot_manager(struct ufs_hba *hba,
struct request_queue *q)
{
- if (hba->caps & UFSHCD_CAP_CRYPTO)
- blk_ksm_register(&hba->ksm, q);
+ if (hba->caps & UFSHCD_CAP_CRYPTO) {
+ /*
+ * This WARN_ON should never trigger since &hba->ksm won't be
+ * "empty" (i.e. will support at least 1 crypto capability), a
+ * UFS device's request queue doesn't support integrity, and
+ * it also satisfies all the block layer constraints (i.e.
+ * supports SG gaps, doesn't have chunk sectors, has a
+ * sufficiently large supported max_segments per bio)
+ */
+ WARN_ON(!blk_ksm_register(&hba->ksm, q));
+ }
}
--
2.25.1


2021-07-23 17:15:16

by Eric Biggers

[permalink] [raw]
Subject: Re: [PATCH v4 5/9] ufshcd: handle error from blk_ksm_register()

On Tue, Jul 06, 2021 at 10:29:39PM -0700, Satya Tangirala wrote:
> From: Satya Tangirala <[email protected]>
>
> Handle any error from blk_ksm_register() in the callers. Previously,
> the callers ignored the return value because blk_ksm_register() wouldn't
> fail as long as the request_queue didn't have integrity support too, but
> as this is no longer the case, it's safer for the callers to just handle
> the return value appropriately.
>
> Signed-off-by: Satya Tangirala <[email protected]>
> ---
> drivers/scsi/ufs/ufshcd-crypto.c | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufshcd-crypto.c b/drivers/scsi/ufs/ufshcd-crypto.c
> index d70cdcd35e43..0fcf9d6752f8 100644
> --- a/drivers/scsi/ufs/ufshcd-crypto.c
> +++ b/drivers/scsi/ufs/ufshcd-crypto.c
> @@ -233,6 +233,15 @@ void ufshcd_init_crypto(struct ufs_hba *hba)
> void ufshcd_crypto_setup_rq_keyslot_manager(struct ufs_hba *hba,
> struct request_queue *q)
> {
> - if (hba->caps & UFSHCD_CAP_CRYPTO)
> - blk_ksm_register(&hba->ksm, q);
> + if (hba->caps & UFSHCD_CAP_CRYPTO) {
> + /*
> + * This WARN_ON should never trigger since &hba->ksm won't be
> + * "empty" (i.e. will support at least 1 crypto capability), a
> + * UFS device's request queue doesn't support integrity, and
> + * it also satisfies all the block layer constraints (i.e.
> + * supports SG gaps, doesn't have chunk sectors, has a
> + * sufficiently large supported max_segments per bio)
> + */
> + WARN_ON(!blk_ksm_register(&hba->ksm, q));
> + }

I guess this looks okay, but I think the comment should be a bit more concise
and not so tied to the current implementation details, like:

/*
* This WARN_ON should never trigger since at least one of the
* declared crypto capabilities should be compatible with the
* UFS device, otherwise the UFS host driver shouldn't have
* declared crypto support at all.
*/

Likewise for the similar MMC crypto patch.

- Eric