* [PATCH] file-posix: allow -EBUSY errors during write zeros on block
@ 2021-03-02 1:56 ChangLimin
2021-03-02 14:10 ` Kevin Wolf
` (2 more replies)
0 siblings, 3 replies; 5+ messages in thread
From: ChangLimin @ 2021-03-02 1:56 UTC (permalink / raw)
To: qemu-block; +Cc: kwolf, qemu-devel, mreitz
After Linux 5.10, write zeros to a multipath device using
ioctl(fd, BLKZEROOUT, range) with cache none or directsync will return EBUSY.
Similar to handle_aiocb_write_zeroes_unmap, handle_aiocb_write_zeroes_block
allow -EBUSY errors during ioctl(fd, BLKZEROOUT, range).
Reference commit in Linux 5.10:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=384d87ef2c954fc58e6c5fd8253e4a1984f5fe02
Signed-off-by: ChangLimin <changlm@chinatelecom.cn>
---
block/file-posix.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/block/file-posix.c b/block/file-posix.c
index 05079b40ca..3e60c96214 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -1629,8 +1629,13 @@ static ssize_t handle_aiocb_write_zeroes_block(RawPosixAIOData *aiocb)
} while (errno == EINTR);
ret = translate_err(-errno);
- if (ret == -ENOTSUP) {
+ switch (ret) {
+ case -ENOTSUP:
+ case -EINVAL:
+ case -EBUSY:
s->has_write_zeroes = false;
+ return -ENOTSUP;
+ break;
}
}
#endif
--
2.27.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] file-posix: allow -EBUSY errors during write zeros on block
2021-03-02 1:56 [PATCH] file-posix: allow -EBUSY errors during write zeros on block ChangLimin
@ 2021-03-02 14:10 ` Kevin Wolf
2021-03-02 16:40 ` Nir Soffer
2021-03-03 3:24 ` [PATCH V2] file-posix: allow -EBUSY -EINVAL " ChangLimin
2 siblings, 0 replies; 5+ messages in thread
From: Kevin Wolf @ 2021-03-02 14:10 UTC (permalink / raw)
To: ChangLimin; +Cc: qemu-devel, qemu-block, mreitz
Am 02.03.2021 um 02:56 hat ChangLimin geschrieben:
> After Linux 5.10, write zeros to a multipath device using
> ioctl(fd, BLKZEROOUT, range) with cache none or directsync will return EBUSY.
>
> Similar to handle_aiocb_write_zeroes_unmap, handle_aiocb_write_zeroes_block
> allow -EBUSY errors during ioctl(fd, BLKZEROOUT, range).
>
> Reference commit in Linux 5.10:
> https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=384d87ef2c954fc58e6c5fd8253e4a1984f5fe02
>
> Signed-off-by: ChangLimin <changlm@chinatelecom.cn>
> ---
> block/file-posix.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/block/file-posix.c b/block/file-posix.c
> index 05079b40ca..3e60c96214 100644
> --- a/block/file-posix.c
> +++ b/block/file-posix.c
> @@ -1629,8 +1629,13 @@ static ssize_t handle_aiocb_write_zeroes_block(RawPosixAIOData *aiocb)
> } while (errno == EINTR);
>
> ret = translate_err(-errno);
> - if (ret == -ENOTSUP) {
> + switch (ret) {
> + case -ENOTSUP:
> + case -EINVAL:
> + case -EBUSY:
> s->has_write_zeroes = false;
Do we actually want -EINVAL and -EBUSY to completely stop us from trying
again in future requests? -ENOTSUP will never change in future calls,
but can't -EINVAL and -EBUSY?
By the way, the commit message only explains -EBUSY. Why do we want to
cover -EINVAL here, too?
> + return -ENOTSUP;
I suppose this is the important change: We convert the error codes to
-ENOTSUP now so that block.c will emulate the operation instead of
failing. This should be explained in the commit message.
> + break;
> }
> }
> #endif
Kevin
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] file-posix: allow -EBUSY errors during write zeros on block
2021-03-02 1:56 [PATCH] file-posix: allow -EBUSY errors during write zeros on block ChangLimin
2021-03-02 14:10 ` Kevin Wolf
@ 2021-03-02 16:40 ` Nir Soffer
2021-03-04 0:14 ` ChangLimin
2021-03-03 3:24 ` [PATCH V2] file-posix: allow -EBUSY -EINVAL " ChangLimin
2 siblings, 1 reply; 5+ messages in thread
From: Nir Soffer @ 2021-03-02 16:40 UTC (permalink / raw)
To: ChangLimin; +Cc: kwolf, qemu-devel, qemu-block, mreitz
On Tue, Mar 2, 2021 at 4:08 AM ChangLimin <changlm@chinatelecom.cn> wrote:
>
> After Linux 5.10, write zeros to a multipath device using
> ioctl(fd, BLKZEROOUT, range) with cache none or directsync will return EBUSY.
>
> Similar to handle_aiocb_write_zeroes_unmap, handle_aiocb_write_zeroes_block
> allow -EBUSY errors during ioctl(fd, BLKZEROOUT, range).
>
> Reference commit in Linux 5.10:
> https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=384d87ef2c954fc58e6c5fd8253e4a1984f5fe02
But this can happen only when the block device is used by a file system or
maybe someone else. In qemu we assume that we are the only user of the
block device, so EBUSY is a fatal error that should never happen, no?
Can you explain a real world use case when we get EBUSY?
Nir
> Signed-off-by: ChangLimin <changlm@chinatelecom.cn>
> ---
> block/file-posix.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/block/file-posix.c b/block/file-posix.c
> index 05079b40ca..3e60c96214 100644
> --- a/block/file-posix.c
> +++ b/block/file-posix.c
> @@ -1629,8 +1629,13 @@ static ssize_t handle_aiocb_write_zeroes_block(RawPosixAIOData *aiocb)
> } while (errno == EINTR);
>
> ret = translate_err(-errno);
> - if (ret == -ENOTSUP) {
> + switch (ret) {
> + case -ENOTSUP:
> + case -EINVAL:
> + case -EBUSY:
> s->has_write_zeroes = false;
> + return -ENOTSUP;
> + break;
> }
> }
> #endif
> --
> 2.27.0
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH V2] file-posix: allow -EBUSY -EINVAL errors during write zeros on block
2021-03-02 1:56 [PATCH] file-posix: allow -EBUSY errors during write zeros on block ChangLimin
2021-03-02 14:10 ` Kevin Wolf
2021-03-02 16:40 ` Nir Soffer
@ 2021-03-03 3:24 ` ChangLimin
2 siblings, 0 replies; 5+ messages in thread
From: ChangLimin @ 2021-03-03 3:24 UTC (permalink / raw)
To: qemu-block; +Cc: kwolf, qemu-devel, mreitz
[-- Attachment #1: Type: text/plain, Size: 1241 bytes --]
Since Linux 5.10, write zeros to a multipath device using
ioctl(fd, BLKZEROOUT, range) with cache none or directsync return -EBUSY
permanently.
Similar to handle_aiocb_write_zeroes_unmap, handle_aiocb_write_zeroes_block
allow -EBUSY and -EINVAL errors during ioctl(fd, BLKZEROOUT, range).
Reference commit in Linux 5.10:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=384d87ef2c954fc58e6c5fd8253e4a1984f5fe02
Signed-off-by: ChangLimin <changlm@chinatelecom.cn>
---
block/file-posix.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/block/file-posix.c b/block/file-posix.c
index 05079b40ca..4e132db929 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -1629,8 +1629,13 @@ static ssize_t handle_aiocb_write_zeroes_block(RawPosixAIOData *aiocb)
} while (errno == EINTR);
ret = translate_err(-errno);
- if (ret == -ENOTSUP) {
- s->has_write_zeroes = false;
+ switch (ret) {
+ case -ENOTSUP:
+ s->has_write_zeroes = false; /* fall through */
+ case -EINVAL:
+ case -EBUSY:
+ return -ENOTSUP;
+ break;
}
}
#endif
--
2.27.0
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^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] file-posix: allow -EBUSY errors during write zeros on block
2021-03-02 16:40 ` Nir Soffer
@ 2021-03-04 0:14 ` ChangLimin
0 siblings, 0 replies; 5+ messages in thread
From: ChangLimin @ 2021-03-04 0:14 UTC (permalink / raw)
To: Nir Soffer; +Cc: kwolf, qemu-devel, qemu-block, mreitz
[-- Attachment #1: Type: text/plain, Size: 1852 bytes --]
>> After Linux 5.10, write zeros to a multipath device using
>> ioctl(fd, BLKZEROOUT, range) with cache none or directsync will return EBUSY.
>>
>> Similar to handle_aiocb_write_zeroes_unmap, handle_aiocb_write_zeroes_block
>> allow -EBUSY errors during ioctl(fd, BLKZEROOUT, range).
>>
>> Reference commit in Linux 5.10:
>> https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=384d87ef2c954fc58e6c5fd8253e4a1984f5fe02
>
>But this can happen only when the block device is used by a file system or
>maybe someone else. In qemu we assume that we are the only user of the
>block device, so EBUSY is a fatal error that should never happen, no?
>
>Can you explain a real world use case when we get EBUSY?
>
>Nir
>
Please refer to https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/configuring_device_mapper_multipath/index
Where multipath is configured to a SAN LUN, ioctl(fd, BLKZEROOUT, range)
to the /dev/dm-x return EBUSY permanently since Linux 5.10.
ChangLimin
>> Signed-off-by: ChangLimin <changlm@chinatelecom.cn>
>> ---
>> block/file-posix.c | 7 ++++++-
>> 1 file changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/block/file-posix.c b/block/file-posix.c
>> index 05079b40ca..3e60c96214 100644
>> --- a/block/file-posix.c
>> +++ b/block/file-posix.c
>> @@ -1629,8 +1629,13 @@ static ssize_t handle_aiocb_write_zeroes_block(RawPosixAIOData *aiocb)
>> } while (errno == EINTR);
>>
>> ret = translate_err(-errno);
>> - if (ret == -ENOTSUP) {
>> + switch (ret) {
>> + case -ENOTSUP:
>> + case -EINVAL:
>> + case -EBUSY:
>> s->has_write_zeroes = false;
>> + return -ENOTSUP;
>> + break;
>> }
>> }
>> #endif
>> --
>> 2.27.0
>>
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^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2021-03-04 0:16 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-03-02 1:56 [PATCH] file-posix: allow -EBUSY errors during write zeros on block ChangLimin
2021-03-02 14:10 ` Kevin Wolf
2021-03-02 16:40 ` Nir Soffer
2021-03-04 0:14 ` ChangLimin
2021-03-03 3:24 ` [PATCH V2] file-posix: allow -EBUSY -EINVAL " ChangLimin
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