* [PATCH] blk-mq: use force attribute for blk_status_t casts
@ 2022-05-14 10:03 Vasily Averin
2022-05-14 21:24 ` Jens Axboe
2022-05-16 6:53 ` Christoph Hellwig
0 siblings, 2 replies; 6+ messages in thread
From: Vasily Averin @ 2022-05-14 10:03 UTC (permalink / raw)
To: Jens Axboe, linux-block; +Cc: kernel, linux-kernel
Fixes sparse warnings:
block/blk-mq.c:1163:36: sparse:
warning: cast from restricted blk_status_t
block/blk-mq.c:1251:17: sparse:
warning: cast to restricted blk_status_t
Signed-off-by: Vasily Averin <vvs@openvz.org>
---
block/blk-mq.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 84d749511f55..1b887f2d4a19 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1160,7 +1160,7 @@ static void blk_end_sync_rq(struct request *rq, blk_status_t error)
{
struct completion *waiting = rq->end_io_data;
- rq->end_io_data = (void *)(uintptr_t)error;
+ rq->end_io_data = (void *)(__force uintptr_t)error;
/*
* complete last, if this is a stack request the process (and thus
@@ -1248,7 +1248,7 @@ blk_status_t blk_execute_rq(struct request *rq, bool at_head)
else
wait_for_completion_io(&wait);
- return (blk_status_t)(uintptr_t)rq->end_io_data;
+ return (__force blk_status_t)(uintptr_t)rq->end_io_data;
}
EXPORT_SYMBOL(blk_execute_rq);
--
2.31.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] blk-mq: use force attribute for blk_status_t casts
2022-05-14 10:03 [PATCH] blk-mq: use force attribute for blk_status_t casts Vasily Averin
@ 2022-05-14 21:24 ` Jens Axboe
2022-05-16 6:53 ` Christoph Hellwig
1 sibling, 0 replies; 6+ messages in thread
From: Jens Axboe @ 2022-05-14 21:24 UTC (permalink / raw)
To: linux-block, Vasily Averin; +Cc: kernel, linux-kernel
On Sat, 14 May 2022 13:03:54 +0300, Vasily Averin wrote:
> Fixes sparse warnings:
> block/blk-mq.c:1163:36: sparse:
> warning: cast from restricted blk_status_t
> block/blk-mq.c:1251:17: sparse:
> warning: cast to restricted blk_status_t
>
>
> [...]
Applied, thanks!
[1/1] blk-mq: use force attribute for blk_status_t casts
commit: cb9e061e974f8a3a8f2b8c89d93f34ffa7cacafb
Best regards,
--
Jens Axboe
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] blk-mq: use force attribute for blk_status_t casts
2022-05-14 10:03 [PATCH] blk-mq: use force attribute for blk_status_t casts Vasily Averin
2022-05-14 21:24 ` Jens Axboe
@ 2022-05-16 6:53 ` Christoph Hellwig
2022-05-18 12:45 ` [PATCH v2] blk-mq: fix incorrect " Vasily Averin
1 sibling, 1 reply; 6+ messages in thread
From: Christoph Hellwig @ 2022-05-16 6:53 UTC (permalink / raw)
To: Vasily Averin; +Cc: Jens Axboe, linux-block, kernel, linux-kernel
No, no, no. Really, stop these patches that just make things worse
now. __force casts are a really bad idea. Please just fix this
in a way that does not require casting away these attributes as they
are there for a reason!
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v2] blk-mq: fix incorrect blk_status_t casts
2022-05-16 6:53 ` Christoph Hellwig
@ 2022-05-18 12:45 ` Vasily Averin
2022-05-18 20:35 ` Chaitanya Kulkarni
2022-05-19 7:53 ` Christoph Hellwig
0 siblings, 2 replies; 6+ messages in thread
From: Vasily Averin @ 2022-05-18 12:45 UTC (permalink / raw)
To: Christoph Hellwig, Jens Axboe; +Cc: kernel, linux-kernel, linux-block
Fixes sparse warnings:
block/blk-mq.c:1163:36: sparse:
warning: cast from restricted blk_status_t
block/blk-mq.c:1251:17: sparse:
warning: cast to restricted blk_status_t
blk_status_t type is bitwaise and requires __force for any casts.
Signed-off-by: Vasily Averin <vvs@openvz.org>
---
v2: introduced request_blk_status_en/decode helpers
thanks Christoph Hellwig for the hint
---
block/blk-mq.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 84d749511f55..8f067b021af3 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1151,6 +1151,16 @@ void blk_mq_start_request(struct request *rq)
}
EXPORT_SYMBOL(blk_mq_start_request);
+static void *request_blk_status_encode(blk_status_t status)
+{
+ return (void *)(__force uintptr_t)status;
+}
+
+static blk_status_t request_blk_status_decode(void *ptr)
+{
+ return (__force blk_status_t)(uintptr_t)ptr;
+}
+
/**
* blk_end_sync_rq - executes a completion event on a request
* @rq: request to complete
@@ -1160,7 +1170,7 @@ static void blk_end_sync_rq(struct request *rq, blk_status_t error)
{
struct completion *waiting = rq->end_io_data;
- rq->end_io_data = (void *)(uintptr_t)error;
+ rq->end_io_data = request_blk_status_encode(error);
/*
* complete last, if this is a stack request the process (and thus
@@ -1228,6 +1238,7 @@ static void blk_rq_poll_completion(struct request *rq, struct completion *wait)
* for execution and wait for completion.
* Return: The blk_status_t result provided to blk_mq_end_request().
*/
+
blk_status_t blk_execute_rq(struct request *rq, bool at_head)
{
DECLARE_COMPLETION_ONSTACK(wait);
@@ -1248,7 +1259,7 @@ blk_status_t blk_execute_rq(struct request *rq, bool at_head)
else
wait_for_completion_io(&wait);
- return (blk_status_t)(uintptr_t)rq->end_io_data;
+ return request_blk_status_decode(rq->end_io_data);
}
EXPORT_SYMBOL(blk_execute_rq);
--
2.31.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH v2] blk-mq: fix incorrect blk_status_t casts
2022-05-18 12:45 ` [PATCH v2] blk-mq: fix incorrect " Vasily Averin
@ 2022-05-18 20:35 ` Chaitanya Kulkarni
2022-05-19 7:53 ` Christoph Hellwig
1 sibling, 0 replies; 6+ messages in thread
From: Chaitanya Kulkarni @ 2022-05-18 20:35 UTC (permalink / raw)
To: Vasily Averin
Cc: kernel, linux-kernel, Jens Axboe, Christoph Hellwig, linux-block
On 5/18/22 05:45, Vasily Averin wrote:
> Fixes sparse warnings:
> block/blk-mq.c:1163:36: sparse:
> warning: cast from restricted blk_status_t
> block/blk-mq.c:1251:17: sparse:
> warning: cast to restricted blk_status_t
>
> blk_status_t type is bitwaise and requires __force for any casts.
>
> Signed-off-by: Vasily Averin <vvs@openvz.org>
> ---
> v2: introduced request_blk_status_en/decode helpers
> thanks Christoph Hellwig for the hint
> ---
> block/blk-mq.c | 15 +++++++++++++--
> 1 file changed, 13 insertions(+), 2 deletions(-)
>
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index 84d749511f55..8f067b021af3 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -1151,6 +1151,16 @@ void blk_mq_start_request(struct request *rq)
> }
> EXPORT_SYMBOL(blk_mq_start_request);
>
> +static void *request_blk_status_encode(blk_status_t status)
> +{
> + return (void *)(__force uintptr_t)status;
> +}
> +
> +static blk_status_t request_blk_status_decode(void *ptr)
> +{
> + return (__force blk_status_t)(uintptr_t)ptr;
> +}
> +
why not use blk_sts_encode() and blk_sts_decode() since both the
functions neither accept request parameter nor return request in any
form ?
-ck
> /**
> * blk_end_sync_rq - executes a completion event on a request
> * @rq: request to complete
> @@ -1160,7 +1170,7 @@ static void blk_end_sync_rq(struct request *rq, blk_status_t error)
> {
> struct completion *waiting = rq->end_io_data;
>
> - rq->end_io_data = (void *)(uintptr_t)error;
> + rq->end_io_data = request_blk_status_encode(error);
>
> /*
> * complete last, if this is a stack request the process (and thus
> @@ -1228,6 +1238,7 @@ static void blk_rq_poll_completion(struct request *rq, struct completion *wait)
> * for execution and wait for completion.
> * Return: The blk_status_t result provided to blk_mq_end_request().
> */
> +
white line ?
> blk_status_t blk_execute_rq(struct request *rq, bool at_head)
> {
> DECLARE_COMPLETION_ONSTACK(wait);
> @@ -1248,7 +1259,7 @@ blk_status_t blk_execute_rq(struct request *rq, bool at_head)
> else
> wait_for_completion_io(&wait);
>
> - return (blk_status_t)(uintptr_t)rq->end_io_data;
> + return request_blk_status_decode(rq->end_io_data);
> }
> EXPORT_SYMBOL(blk_execute_rq);
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2] blk-mq: fix incorrect blk_status_t casts
2022-05-18 12:45 ` [PATCH v2] blk-mq: fix incorrect " Vasily Averin
2022-05-18 20:35 ` Chaitanya Kulkarni
@ 2022-05-19 7:53 ` Christoph Hellwig
1 sibling, 0 replies; 6+ messages in thread
From: Christoph Hellwig @ 2022-05-19 7:53 UTC (permalink / raw)
To: Vasily Averin
Cc: Christoph Hellwig, Jens Axboe, kernel, linux-kernel, linux-block
Still a whole lot of casts. Take a look at my "cleanup blk_execute_rq*"
for how think we can solve this in a much nicer way.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-05-19 7:53 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2022-05-14 10:03 [PATCH] blk-mq: use force attribute for blk_status_t casts Vasily Averin
2022-05-14 21:24 ` Jens Axboe
2022-05-16 6:53 ` Christoph Hellwig
2022-05-18 12:45 ` [PATCH v2] blk-mq: fix incorrect " Vasily Averin
2022-05-18 20:35 ` Chaitanya Kulkarni
2022-05-19 7:53 ` Christoph Hellwig
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