seq_file: add helper macro to define attribute for rw file

seq_file: add helper macro to define attribute for rw file

Patch series "Add helper macro DEFINE_SHOW_STORE_ATTRIBUTE() at
seq_file.c", v6.

We already own DEFINE_SHOW_ATTRIBUTE() helper macro for defining attribute
for read-only file, but we found many of drivers also want a helper macro
for read-write file too.

So we add this helper macro to reduce duplicated code.

This patch (of 3):

We already own DEFINE_SHOW_ATTRIBUTE() helper macro for defining attribute
for read-only file, but many of drivers want a helper macro for read-write
file too.

So we add DEFINE_SHOW_STORE_ATTRIBUTE() helper to reduce duplicated code.

Link: https://lkml.kernel.org/r/20230905024835.43219-1-yangxingui@huawei.com
Link: https://lkml.kernel.org/r/20230905024835.43219-2-yangxingui@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Co-developed-by: Xingui Yang <yangxingui@huawei.com>
Signed-off-by: Xingui Yang <yangxingui@huawei.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Animesh Manna <animesh.manna@intel.com>
Cc: Anshuman Gupta <anshuman.gupta@intel.com>
Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Himanshu Madhani <himanshu.madhani@cavium.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Uma Shankar <uma.shankar@intel.com>
Cc: Xiang Chen <chenxiang66@hisilicon.com>
Cc: Zeng Tao <prime.zeng@hisilicon.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>