[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH v4 5/6] util: give a specific error message when O_DIRECT doe
From: |
Markus Armbruster |
Subject: |
Re: [PATCH v4 5/6] util: give a specific error message when O_DIRECT doesn't work |
Date: |
Tue, 25 Aug 2020 17:19:53 +0200 |
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) |
Daniel P. Berrangé <berrange@redhat.com> writes:
> A common error scenario is to tell QEMU to use O_DIRECT in combination
> with a filesystem that doesn't support it. To aid users to diagnosing
> their mistake we want to provide a clear error message when this happens.
>
> Reviewed-by: Eric Blake <eblake@redhat.com>
> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
> ---
> util/osdep.c | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/util/osdep.c b/util/osdep.c
> index a4956fbf6b..6c24985f7a 100644
> --- a/util/osdep.c
> +++ b/util/osdep.c
> @@ -345,6 +345,19 @@ qemu_open_internal(const char *name, int flags, mode_t
> mode, Error **errp)
>
> if (ret == -1) {
> const char *action = flags & O_CREAT ? "create" : "open";
> +#ifdef O_DIRECT
> + if (errno == EINVAL && (flags & O_DIRECT)) {
> + ret = open(name, flags & ~O_DIRECT, mode);
> + if (ret != -1) {
> + close(ret);
> + error_setg(errp, "Could not %s '%s' flags 0x%x: "
> + "filesystem does not support O_DIRECT",
> + action, name, flags);
> + errno = EINVAL; /* close() clobbered earlier errno */
More precise: close() may have clobbered
Sure open() can only fail with EINVAL here?
> + return -1;
> + }
> + }
> +#endif /* O_DIRECT */
> error_setg_errno(errp, errno, "Could not %s '%s' flags 0x%x",
> action, name, flags);
> }
There is no qemu_set_cloexec(). Intentional?
- Re: [PATCH v4 2/6] util: refactor qemu_open_old to split off variadic args handling, (continued)
[PATCH v4 3/6] util: add Error object for qemu_open_internal error reporting, Daniel P . Berrangé, 2020/08/21
[PATCH v4 4/6] util: introduce qemu_open and qemu_create with error reporting, Daniel P . Berrangé, 2020/08/21
[PATCH v4 5/6] util: give a specific error message when O_DIRECT doesn't work, Daniel P . Berrangé, 2020/08/21
- Re: [PATCH v4 5/6] util: give a specific error message when O_DIRECT doesn't work,
Markus Armbruster <=
[PATCH v4 6/6] block/fileb: switch to use qemu_open/qemu_create for improved errors, Daniel P . Berrangé, 2020/08/21