The 'struct module_attribute' sysfs callbacks are about to change to
receive a 'const struct module_attribute *' parameter.
Prepare for that by avoid casting away the constness through
container_of() and using const pointers to 'struct param_attribute'.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Link: https://lore.kernel.org/r/20241216-sysfs-const-attr-module-v1-1-3790b53e0abf@weissschuh.net
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>

The structure is always read-only due to its placement in the read-only
section __modver. Reflect this at its usage sites.
Also prepare for the const handling of 'struct module_attribute' itself.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Link: https://lore.kernel.org/r/20241216-sysfs-const-attr-module-v1-2-3790b53e0abf@weissschuh.net
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>

These structs are never modified, move them to read-only memory.
This makes the API clearer and also prepares for the constification of
'struct attribute' itself.

While at it, also constify 'modinfo_attrs_count'.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Link: https://lore.kernel.org/r/20241216-sysfs-const-attr-module-v1-3-3790b53e0abf@weissschuh.net
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>

The member is only used to iterate over all attributes in
free_sect_attrs(). However the attribute group can already be used for
that. Use the group and drop 'nsections'.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>

'struct bin_attribute' already contains the member 'private' to pass
custom data to the attribute handlers.
Use that instead of the custom 'address' member.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>

This is now an otherwise empty wrapper around a 'struct bin_attribute',
not providing any functionality. Remove it.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>

The existing allocation logic manually stuffs two allocations into one.
This is hard to understand and of limited value, given that all the
section names are allocated on their own anyways.
Une one allocation per datastructure.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>

A kobject is meant to manage the lifecycle of some resource.
However the module sysfs code only creates a kobject to get a
"notes" subdirectory in sysfs.
This can be achieved easier and cheaper by using a sysfs group.
Switch the notes attribute code to such a group, similar to how the
section allocation in the same file already works.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>

The sysfs core is switching to 'const struct bin_attribute's.
Prepare for that.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>