char: misc: Adapt and add test cases for simple minor space division

Adapt and add test cases for next change which regards minor whose
value > macro MISC_DYNAMIC_MINOR as invalid parameter when register
miscdevice, hence get a simple minor space division below:

<  MISC_DYNAMIC_MINOR: fixed minor code
== MISC_DYNAMIC_MINOR: indicator to request dynamic minor code
>  MISC_DYNAMIC_MINOR: dynamic minor code requested

Signed-off-by: Zijun Hu <zijun.hu@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250714-rfc_miscdev-v6-2-2ed949665bde@oss.qualcomm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Zijun Hu
2025-07-14 23:34:13 +08:00
committed by Greg Kroah-Hartman
parent 8ac646d6df
commit f4e47affdb

View File

@@ -7,12 +7,6 @@
#include <linux/file.h>
#include <linux/init_syscalls.h>
/* dynamic minor (2) */
static struct miscdevice dev_dynamic_minor = {
.minor = 2,
.name = "dev_dynamic_minor",
};
/* static minor (LCD_MINOR) */
static struct miscdevice dev_static_minor = {
.minor = LCD_MINOR,
@@ -25,16 +19,6 @@ static struct miscdevice dev_misc_dynamic_minor = {
.name = "dev_misc_dynamic_minor",
};
static void kunit_dynamic_minor(struct kunit *test)
{
int ret;
ret = misc_register(&dev_dynamic_minor);
KUNIT_EXPECT_EQ(test, 0, ret);
KUNIT_EXPECT_EQ(test, 2, dev_dynamic_minor.minor);
misc_deregister(&dev_dynamic_minor);
}
static void kunit_static_minor(struct kunit *test)
{
int ret;
@@ -157,13 +141,7 @@ static bool is_valid_dynamic_minor(int minor)
{
if (minor < 0)
return false;
if (minor == MISC_DYNAMIC_MINOR)
return false;
if (minor >= 0 && minor <= 15)
return false;
if (minor >= 128 && minor < MISC_DYNAMIC_MINOR)
return false;
return true;
return minor > MISC_DYNAMIC_MINOR;
}
static int miscdev_test_open(struct inode *inode, struct file *file)
@@ -557,7 +535,7 @@ static void __init miscdev_test_conflict(struct kunit *test)
*/
miscstat.minor = miscdyn.minor;
ret = misc_register(&miscstat);
KUNIT_EXPECT_EQ(test, ret, -EBUSY);
KUNIT_EXPECT_EQ(test, ret, -EINVAL);
if (ret == 0)
misc_deregister(&miscstat);
@@ -590,8 +568,9 @@ static void __init miscdev_test_conflict_reverse(struct kunit *test)
misc_deregister(&miscdyn);
ret = misc_register(&miscstat);
KUNIT_EXPECT_EQ(test, ret, 0);
KUNIT_EXPECT_EQ(test, miscstat.minor, miscdyn.minor);
KUNIT_EXPECT_EQ(test, ret, -EINVAL);
if (ret == 0)
misc_deregister(&miscstat);
/*
* Try to register a dynamic minor after registering a static minor
@@ -601,20 +580,32 @@ static void __init miscdev_test_conflict_reverse(struct kunit *test)
miscdyn.minor = MISC_DYNAMIC_MINOR;
ret = misc_register(&miscdyn);
KUNIT_EXPECT_EQ(test, ret, 0);
KUNIT_EXPECT_NE(test, miscdyn.minor, miscstat.minor);
KUNIT_EXPECT_EQ(test, miscdyn.minor, miscstat.minor);
KUNIT_EXPECT_TRUE(test, is_valid_dynamic_minor(miscdyn.minor));
if (ret == 0)
misc_deregister(&miscdyn);
}
miscdev_test_can_open(test, &miscstat);
/* Take minor(> MISC_DYNAMIC_MINOR) as invalid when register miscdevice */
static void miscdev_test_invalid_input(struct kunit *test)
{
struct miscdevice misc_test = {
.minor = MISC_DYNAMIC_MINOR + 1,
.name = "misc_test",
.fops = &miscdev_test_fops,
};
int ret;
misc_deregister(&miscstat);
ret = misc_register(&misc_test);
KUNIT_EXPECT_EQ(test, ret, -EINVAL);
if (ret == 0)
misc_deregister(&misc_test);
}
static struct kunit_case test_cases[] = {
KUNIT_CASE(kunit_dynamic_minor),
KUNIT_CASE(kunit_static_minor),
KUNIT_CASE(kunit_misc_dynamic_minor),
KUNIT_CASE(miscdev_test_invalid_input),
KUNIT_CASE_PARAM(miscdev_test_twice, miscdev_gen_params),
KUNIT_CASE_PARAM(miscdev_test_duplicate_minor, miscdev_gen_params),
KUNIT_CASE(miscdev_test_duplicate_name),