2023-10-05 15:58:38

by Greg Kroah-Hartman

Subject: [PATCH 2/2] tty: vc_screen: make vc_class constant

Now that the driver core allows for struct class to be in read-only
memory, making all 'class' structures to be declared at build time
placing them into read-only memory, instead of having to be dynamically
allocated at load time.

Cc: Jiri Slaby <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
drivers/tty/vt/vc_screen.c | 28 ++++++++++++++--------------
1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/tty/vt/vc_screen.c b/drivers/tty/vt/vc_screen.c
index 829c4be66f3b..b16ea517bb17 100644
--- a/drivers/tty/vt/vc_screen.c
+++ b/drivers/tty/vt/vc_screen.c
@@ -786,23 +786,22 @@ static const struct file_operations vcs_fops = {
.release = vcs_release,
};

-static struct class *vc_class;
+static const struct class vc_class = {
+ .name = "vc",
+};

void vcs_make_sysfs(int index)
{
- device_create(vc_class, NULL, MKDEV(VCS_MAJOR, index + 1), NULL,
- "vcs%u", index + 1);
- device_create(vc_class, NULL, MKDEV(VCS_MAJOR, index + 65), NULL,
- "vcsu%u", index + 1);
- device_create(vc_class, NULL, MKDEV(VCS_MAJOR, index + 129), NULL,
- "vcsa%u", index + 1);
+ device_create(&vc_class, NULL, MKDEV(VCS_MAJOR, index + 1), NULL, "vcs%u", index + 1);
+ device_create(&vc_class, NULL, MKDEV(VCS_MAJOR, index + 65), NULL, "vcsu%u", index + 1);
+ device_create(&vc_class, NULL, MKDEV(VCS_MAJOR, index + 129), NULL, "vcsa%u", index + 1);
}

void vcs_remove_sysfs(int index)
{
- device_destroy(vc_class, MKDEV(VCS_MAJOR, index + 1));
- device_destroy(vc_class, MKDEV(VCS_MAJOR, index + 65));
- device_destroy(vc_class, MKDEV(VCS_MAJOR, index + 129));
+ device_destroy(&vc_class, MKDEV(VCS_MAJOR, index + 1));
+ device_destroy(&vc_class, MKDEV(VCS_MAJOR, index + 65));
+ device_destroy(&vc_class, MKDEV(VCS_MAJOR, index + 129));
}

int __init vcs_init(void)
@@ -811,11 +810,12 @@ int __init vcs_init(void)

if (register_chrdev(VCS_MAJOR, "vcs", &vcs_fops))
panic("unable to get major %d for vcs device", VCS_MAJOR);
- vc_class = class_create("vc");
+ if (class_register(&vc_class))
+ panic("unable to create vc_class");

- device_create(vc_class, NULL, MKDEV(VCS_MAJOR, 0), NULL, "vcs");
- device_create(vc_class, NULL, MKDEV(VCS_MAJOR, 64), NULL, "vcsu");
- device_create(vc_class, NULL, MKDEV(VCS_MAJOR, 128), NULL, "vcsa");
+ device_create(&vc_class, NULL, MKDEV(VCS_MAJOR, 0), NULL, "vcs");
+ device_create(&vc_class, NULL, MKDEV(VCS_MAJOR, 64), NULL, "vcsu");
+ device_create(&vc_class, NULL, MKDEV(VCS_MAJOR, 128), NULL, "vcsa");
for (i = 0; i < MIN_NR_CONSOLES; i++)
vcs_make_sysfs(i);
return 0;
--
2.42.0

2023-10-09 05:28:20

by Jiri Slaby

Subject: Re: [PATCH 2/2] tty: vc_screen: make vc_class constant

On 05. 10. 23, 15:33, Greg Kroah-Hartman wrote:
> Now that the driver core allows for struct class to be in read-only
> memory, making all 'class' structures to be declared at build time
> placing them into read-only memory, instead of having to be dynamically
> allocated at load time.
>
> Cc: Jiri Slaby <[email protected]>
> Signed-off-by: Greg Kroah-Hartman <[email protected]>
> ---
> drivers/tty/vt/vc_screen.c | 28 ++++++++++++++--------------
> 1 file changed, 14 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/tty/vt/vc_screen.c b/drivers/tty/vt/vc_screen.c
> index 829c4be66f3b..b16ea517bb17 100644
> --- a/drivers/tty/vt/vc_screen.c
> +++ b/drivers/tty/vt/vc_screen.c
...
> @@ -811,11 +810,12 @@ int __init vcs_init(void)
>
> if (register_chrdev(VCS_MAJOR, "vcs", &vcs_fops))
> panic("unable to get major %d for vcs device", VCS_MAJOR);
> - vc_class = class_create("vc");
> + if (class_register(&vc_class))
> + panic("unable to create vc_class");

FWIW it's no longer "create". Now it's "register".

Anyway, for the sake of archives:
Reviewed-by: Jiri Slaby <[email protected]>

regards,
--
js
suse labs