Commit ec2f40bd authored by Russell Currey's avatar Russell Currey Committed by Michael Ellerman
Browse files

powerpc/secvar: Handle format string in the consumer 



The code that handles the format string in secvar-sysfs.c is entirely
OPAL specific, so create a new "format" op in secvar_operations to make
the secvar code more generic.  No functional change.

Signed-off-by: default avatarRussell Currey <ruscur@russell.cc>
Signed-off-by: default avatarAndrew Donnellan <ajd@linux.ibm.com>
Reviewed-by: default avatarStefan Berger <stefanb@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230210080401.345462-8-ajd@linux.ibm.com
parent 16943a2f

arch/powerpc/include/asm/secvar.h

+1 −0
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ struct secvar_operations { 
	int (*get)(const char *key, u64 key_len, u8 *data, u64 *data_size);

	int (*get_next)(const char *key, u64 *key_len, u64 keybufsize);

	int (*set)(const char *key, u64 key_len, u8 *data, u64 data_size);

	ssize_t (*format)(char *buf, size_t bufsize);

};



#ifdef CONFIG_PPC_SECURE_BOOT

arch/powerpc/kernel/secvar-sysfs.c

+9 −18
Original line number Diff line number Diff line
@@ -21,26 +21,17 @@ static struct kset *secvar_kset; 
static ssize_t format_show(struct kobject *kobj, struct kobj_attribute *attr,

			   char *buf)

{

	ssize_t rc = 0;

	struct device_node *node;

	const char *format;



	node = of_find_compatible_node(NULL, NULL, "ibm,secvar-backend");

	if (!of_device_is_available(node)) {

		rc = -ENODEV;

		goto out;

	}

	char tmp[32];

	ssize_t len = secvar_ops->format(tmp, sizeof(tmp));



	rc = of_property_read_string(node, "format", &format);

	if (rc)

		goto out;



	rc = sysfs_emit(buf, "%s\n", format);



out:

	of_node_put(node);

	if (len > 0)

		return sysfs_emit(buf, "%s\n", tmp);

	else if (len < 0)

		pr_err("Error %zd reading format string\n", len);

	else

		pr_err("Got empty format string from backend\n");



	return rc;

	return -EIO;

}

arch/powerpc/platforms/powernv/opal-secvar.c

+25 −0
Original line number Diff line number Diff line
@@ -98,10 +98,35 @@ static int opal_set_variable(const char *key, u64 ksize, u8 *data, u64 dsize) 
	return opal_status_to_err(rc);

}



static ssize_t opal_secvar_format(char *buf, size_t bufsize)

{

	ssize_t rc = 0;

	struct device_node *node;

	const char *format;



	node = of_find_compatible_node(NULL, NULL, "ibm,secvar-backend");

	if (!of_device_is_available(node)) {

		rc = -ENODEV;

		goto out;

	}



	rc = of_property_read_string(node, "format", &format);

	if (rc)

		goto out;



	rc = snprintf(buf, bufsize, "%s", format);



out:

	of_node_put(node);



	return rc;

}



static const struct secvar_operations opal_secvar_ops = {

	.get = opal_get_variable,

	.get_next = opal_get_next_variable,

	.set = opal_set_variable,

	.format = opal_secvar_format,

};



static int opal_secvar_probe(struct platform_device *pdev)