[3/6] parport: Remove register_sysctl_table from parport_device_proc_register
Commit Message
This is part of the general push to deprecate register_sysctl_paths and
register_sysctl_table. We use a temp allocation to include both port and
device name in proc. Allocated mem is freed at the end. The unused
parport_device_sysctl_template struct elements that are not used are
removed.
Signed-off-by: Joel Granados <j.granados@samsung.com>
---
drivers/parport/procfs.c | 57 +++++++++++++++++++++++-----------------
1 file changed, 33 insertions(+), 24 deletions(-)
Comments
On Mon, May 15, 2023 at 09:14:43AM +0200, Joel Granados wrote:
> This is part of the general push to deprecate register_sysctl_paths and
> register_sysctl_table. We use a temp allocation to include both port and
> device name in proc. Allocated mem is freed at the end. The unused
> parport_device_sysctl_template struct elements that are not used are
> removed.
>
> Signed-off-by: Joel Granados <j.granados@samsung.com>
> ---
> drivers/parport/procfs.c | 57 +++++++++++++++++++++++-----------------
> 1 file changed, 33 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/parport/procfs.c b/drivers/parport/procfs.c
> index 53ae5cb98190..902547eb045c 100644
> --- a/drivers/parport/procfs.c
> +++ b/drivers/parport/procfs.c
> @@ -384,6 +384,7 @@ parport_device_sysctl_template = {
> .extra1 = (void*) &parport_min_timeslice_value,
> .extra2 = (void*) &parport_max_timeslice_value
> },
> + {}
> },
> {
> {
> @@ -394,22 +395,6 @@ parport_device_sysctl_template = {
> .child = NULL
> },
> {}
> - },
> - {
> - PARPORT_DEVICES_ROOT_DIR,
> - {}
> - },
> - {
> - PARPORT_PORT_DIR(NULL),
> - {}
> - },
> - {
> - PARPORT_PARPORT_DIR(NULL),
> - {}
> - },
> - {
> - PARPORT_DEV_DIR(NULL),
> - {}
> }
> };
>
> @@ -547,30 +532,54 @@ int parport_proc_unregister(struct parport *port)
>
> int parport_device_proc_register(struct pardevice *device)
> {
> + int err = 0;
> struct parport_device_sysctl_table *t;
> struct parport * port = device->port;
> + size_t port_name_len, device_name_len, tmp_dir_path_len;
> + char *tmp_dir_path;
>
> t = kmemdup(&parport_device_sysctl_template, sizeof(*t), GFP_KERNEL);
> if (t == NULL)
> return -ENOMEM;
>
> - t->dev_dir[0].child = t->parport_dir;
> - t->parport_dir[0].child = t->port_dir;
> - t->port_dir[0].procname = port->name;
> - t->port_dir[0].child = t->devices_root_dir;
> - t->devices_root_dir[0].child = t->device_dir;
> + port_name_len = strnlen(port->name, PARPORT_NAME_MAX_LEN);
> + device_name_len = strnlen(device->name, PATH_MAX);
> +
> + /* Allocate a buffer for two paths: dev/parport/PORT/devices/DEVICE. */
> + tmp_dir_path_len = PARPORT_BASE_DEVICES_PATH_SIZE + port_name_len + device_name_len;
> + tmp_dir_path = kmalloc(tmp_dir_path_len, GFP_KERNEL);
> + if (!tmp_dir_path) {
> + err = -ENOMEM;
> + goto exit_free_t;
> + }
> +
> + if (tmp_dir_path_len
> + <= snprintf(tmp_dir_path, tmp_dir_path_len, "dev/parport/%s/devices/%s",
> + port->name, device->name)) {
> + err = -ENOENT;
> + goto exit_free_path;
> + }
>
> - t->device_dir[0].procname = device->name;
> - t->device_dir[0].child = t->vars;
> t->vars[0].data = &device->timeslice;
>
> - t->sysctl_header = register_sysctl_table(t->dev_dir);
> + t->sysctl_header = register_sysctl(tmp_dir_path, t->vars);
> if (t->sysctl_header == NULL) {
> kfree(t);
> t = NULL;
In the paprport_proc_register there is the same logic where we do not
return error code on error. Additionally, noone checks the return values
of parport_proc_register nor parport_device_proc_register. Should we
just change these to void and be done with it? Or is it better to change
parport/share.c to take care of the error codes?
I realized this after some comments from 0-day.
Best
> }
> device->sysctl_table = t;
> +
> + kfree(tmp_dir_path);
> return 0;
> +
> +exit_free_path:
> + kfree(tmp_dir_path);
> +
> +exit_free_t:
> + kfree(t);
> + t = NULL;
> +
> + return err;
> }
>
> int parport_device_proc_unregister(struct pardevice *device)
> --
> 2.30.2
>
@@ -384,6 +384,7 @@ parport_device_sysctl_template = {
.extra1 = (void*) &parport_min_timeslice_value,
.extra2 = (void*) &parport_max_timeslice_value
},
+ {}
},
{
{
@@ -394,22 +395,6 @@ parport_device_sysctl_template = {
.child = NULL
},
{}
- },
- {
- PARPORT_DEVICES_ROOT_DIR,
- {}
- },
- {
- PARPORT_PORT_DIR(NULL),
- {}
- },
- {
- PARPORT_PARPORT_DIR(NULL),
- {}
- },
- {
- PARPORT_DEV_DIR(NULL),
- {}
}
};
@@ -547,30 +532,54 @@ int parport_proc_unregister(struct parport *port)
int parport_device_proc_register(struct pardevice *device)
{
+ int err = 0;
struct parport_device_sysctl_table *t;
struct parport * port = device->port;
+ size_t port_name_len, device_name_len, tmp_dir_path_len;
+ char *tmp_dir_path;
t = kmemdup(&parport_device_sysctl_template, sizeof(*t), GFP_KERNEL);
if (t == NULL)
return -ENOMEM;
- t->dev_dir[0].child = t->parport_dir;
- t->parport_dir[0].child = t->port_dir;
- t->port_dir[0].procname = port->name;
- t->port_dir[0].child = t->devices_root_dir;
- t->devices_root_dir[0].child = t->device_dir;
+ port_name_len = strnlen(port->name, PARPORT_NAME_MAX_LEN);
+ device_name_len = strnlen(device->name, PATH_MAX);
+
+ /* Allocate a buffer for two paths: dev/parport/PORT/devices/DEVICE. */
+ tmp_dir_path_len = PARPORT_BASE_DEVICES_PATH_SIZE + port_name_len + device_name_len;
+ tmp_dir_path = kmalloc(tmp_dir_path_len, GFP_KERNEL);
+ if (!tmp_dir_path) {
+ err = -ENOMEM;
+ goto exit_free_t;
+ }
+
+ if (tmp_dir_path_len
+ <= snprintf(tmp_dir_path, tmp_dir_path_len, "dev/parport/%s/devices/%s",
+ port->name, device->name)) {
+ err = -ENOENT;
+ goto exit_free_path;
+ }
- t->device_dir[0].procname = device->name;
- t->device_dir[0].child = t->vars;
t->vars[0].data = &device->timeslice;
- t->sysctl_header = register_sysctl_table(t->dev_dir);
+ t->sysctl_header = register_sysctl(tmp_dir_path, t->vars);
if (t->sysctl_header == NULL) {
kfree(t);
t = NULL;
}
device->sysctl_table = t;
+
+ kfree(tmp_dir_path);
return 0;
+
+exit_free_path:
+ kfree(tmp_dir_path);
+
+exit_free_t:
+ kfree(t);
+ t = NULL;
+
+ return err;
}
int parport_device_proc_unregister(struct pardevice *device)