Commit 820879ee authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Greg Kroah-Hartman
Browse files

sysfs: simplify sysfs_kf_seq_show 



Contrary to the comment ->show is never called from lseek for sysfs,
given that sysfs does not use seq_lseek.  So remove the NULL ->show
case and just WARN and return an error if some future code path ends
up here.

Acked-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210913054121.616001-7-hch@lst.de


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent d1a1a960

fs/sysfs/file.c

+6 −9
Original line number Diff line number Diff line
@@ -45,6 +45,9 @@ static int sysfs_kf_seq_show(struct seq_file *sf, void *v) 
	ssize_t count;

	char *buf;



	if (WARN_ON_ONCE(!ops->show))

		return -EINVAL;



	/* acquire buffer and ensure that it's >= PAGE_SIZE and clear */

	count = seq_get_buf(sf, &buf);

	if (count < PAGE_SIZE) {
@@ -53,15 +56,9 @@ static int sysfs_kf_seq_show(struct seq_file *sf, void *v) 
	}

	memset(buf, 0, PAGE_SIZE);



	/*

	 * Invoke show().  Control may reach here via seq file lseek even

	 * if @ops->show() isn't implemented.

	 */

	if (ops->show) {

	count = ops->show(kobj, of->kn->priv, buf);

	if (count < 0)

		return count;

	}



	/*

	 * The code works fine with PAGE_SIZE return but it's likely to