Commit 73f0718e authored by Rob Ward's avatar Rob Ward Committed by Greg Kroah-Hartman
Browse files

drivers: char: mem: Make /dev/mem an optional device 



Adds Kconfig option CONFIG_DEVMEM that allows the
/dev/mem device to be disabled.

Option defaults to /dev/mem enabled.

Signed-off-by: default avatarRob Ward <robert.ward114@googlemail.com>
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 769105aa

drivers/char/Kconfig

+9 −0
Original line number Diff line number Diff line
@@ -6,6 +6,15 @@ menu "Character devices" 


source "drivers/tty/Kconfig"



config DEVMEM

	bool "/dev/mem virtual device support"

	default y

	help

	  Say Y here if you want to support the /dev/mem device.

	  The /dev/mem device is used to access areas of physical

	  memory.

	  When in doubt, say "Y".



config DEVKMEM

	bool "/dev/kmem virtual device support"

	default y

drivers/char/mem.c

+3 −1
Original line number Diff line number Diff line
@@ -715,7 +715,7 @@ static int open_port(struct inode *inode, struct file *filp) 
#define open_mem	open_port

#define open_kmem	open_mem



static const struct file_operations mem_fops = {

static const struct file_operations __maybe_unused mem_fops = {

	.llseek		= memory_lseek,

	.read		= read_mem,

	.write		= write_mem,
@@ -785,7 +785,9 @@ static const struct memdev { 
	const struct file_operations *fops;

	struct backing_dev_info *dev_info;

} devlist[] = {

#ifdef CONFIG_DEVMEM

	 [1] = { "mem", 0, &mem_fops, &directly_mappable_cdev_bdi },

#endif

#ifdef CONFIG_DEVKMEM

	 [2] = { "kmem", 0, &kmem_fops, &directly_mappable_cdev_bdi },

#endif

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