Re: [PATCH 26/39] rtc/proc: switch to proc_create_single_data

Alexandre Belloni
2018-04-19T13:10:27Z

On 19/04/2018 14:41:27+0200, Christoph Hellwig wrote:
> And stop trying to get a reference on the submodule, procfs code deals
> with release after and unloaded module and thus removed proc entry.
>

Are you sure about that? The rtc module is not the one adding the procfs
file so I'm not sure how the procfs code can handle it.

> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
> drivers/rtc/rtc-proc.c | 33 ++-------------------------------
> 1 file changed, 2 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/rtc/rtc-proc.c b/drivers/rtc/rtc-proc.c
> index 31e7e23cc5be..a9dd9218fae2 100644
> --- a/drivers/rtc/rtc-proc.c
> +++ b/drivers/rtc/rtc-proc.c
> @@ -107,40 +107,11 @@ static int rtc_proc_show(struct seq_file *seq, void *offset)
> return 0;
> }
>
> -static int rtc_proc_open(struct inode *inode, struct file *file)
> -{
> - int ret;
> - struct rtc_device *rtc = PDE_DATA(inode);
> -
> - if (!try_module_get(rtc->owner))
> - return -ENODEV;
> -
> - ret = single_open(file, rtc_proc_show, rtc);
> - if (ret)
> - module_put(rtc->owner);
> - return ret;
> -}
> -
> -static int rtc_proc_release(struct inode *inode, struct file *file)
> -{
> - int res = single_release(inode, file);
> - struct rtc_device *rtc = PDE_DATA(inode);
> -
> - module_put(rtc->owner);
> - return res;
> -}
> -
> -static const struct file_operations rtc_proc_fops = {
> - .open = rtc_proc_open,
> - .read = seq_read,
> - .llseek = seq_lseek,
> - .release = rtc_proc_release,
> -};
> -
> void rtc_proc_add_device(struct rtc_device *rtc)
> {
> if (is_rtc_hctosys(rtc))
> - proc_create_data("driver/rtc", 0, NULL, &rtc_proc_fops, rtc);
> + proc_create_single_data("driver/rtc", 0, NULL, rtc_proc_show,
> + rtc);
> }
>
> void rtc_proc_del_device(struct rtc_device *rtc)
> --
> 2.17.0
>

--
Alexandre Belloni, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering