BitMap : add a simple example for API test

Change-Id: I2dac5e59375f6512bf213e88695f202786781cf1

.gitignore

@@ -0,0 +1,7 @@
+*.cmd
+*.o
+*.mod.c
+*.ko
+*.order
+Module.symvers
+.tmp_versions

README.md

@@ -9,3 +9,5 @@
 [tiny4412](https://github.com/54shady/kernel_drivers_examples/tree/tiny4412)
 
 [mini2440](https://github.com/54shady/kernel_drivers_examples/tree/mini2440)
+
+[x86](https://github.com/54shady/kernel_drivers_examples/tree/x86)

debug/bitmap/Makefile

@@ -0,0 +1,37 @@
+# Makefile
+# Comment/uncomment the following line to disable/enable debugging
+# DEBUG = y
+
+# Usage
+# make CROSS_COMPILE=<cross_compiler_prefix> KERNEL_DIR=<your_kernel_dir> KERNEL_BUID_OUTPUT=<kernel_buid_output>
+#
+# make CROSS_COMPILE=/home/zeroway/rk3399/tool/gcc-linaro-4.9.4-2017.01-i686_aarch64-linux-gnu/bin/aarch64-linux-gnu- KERNEL_DIR=/home/zeroway/rk3399/src/firefly/kernel KERNEL_BUID_OUTPUT=/home/zeroway/rk3399/src/firefly/out/target/product/rk3399_firefly_box/obj/KERNEL
+
+# Add your debugging flag (or not) to CFLAGS
+ifeq ($(DEBUG),y)
+DEBFLAGS = -O -g -DSCULL_DEBUG # "-O" is needed to expand inlines
+else
+DEBFLAGS = -O2
+endif
+
+obj-m := bitmap_test.o
+
+KERNEL_DIR ?= /lib/modules/`uname -r`/build
+KERNEL_BUID_OUTPUT ?=$(KERNEL_DIR)
+CC = $(CROSS_COMPILE)gcc
+LD = $(CROSS_COMPILE)ld
+PWD := $(shell pwd)
+ARCH := x86_64
+
+modules:
+	$(MAKE) -C $(KERNEL_DIR) ARCH=$(ARCH) M=$(PWD) O=$(KERNEL_DIR) modules
+
+clean:
+	rm -rf *.o *~ core .depend .*.cmd *.ko *.mod.c .tmp_versions modules.order Module.symvers
+
+depend .depend dep:
+	$(CC) $(CFLAGS) -M *.c > .depend
+
+ifeq (.depend,$(wildcard .depend))
+include .depend
+endif

debug/bitmap/bitmap_test.c

@@ -0,0 +1,97 @@
+#include <linux/init.h>
+#include <linux/module.h>
+
+/* https://www.cnblogs.com/schips/p/10674687.html */
+
+#define BITMAP_LEN 10
+
+#define USING_UNLONG
+#ifdef USING_UNLONG
+unsigned long mybm[1];
+#else
+DECLARE_BITMAP(mybm, BITMAP_LEN);
+#endif
+
+static int bitmap_test_init(void)
+{
+	int bit;
+
+	/* architecture specifiy API */
+	/*
+	 * non atomic version
+	 * include/asm-generic/bitops/instrumented-non-atomic.h
+	 */
+	__set_bit(1, mybm);
+	/*
+	 * arch___set_bit(nr, addr);
+	 * asm volatile(__ASM_SIZE(bts) " %1,%0" : : ADDR, "Ir" (nr) : "memory");
+	 */
+	if (!test_bit(1, mybm))
+		printk(KERN_ALERT" bit 1 tested not set\n");
+	else
+		printk(KERN_ALERT" bit 1 tested set\n");
+
+	__clear_bit(1, mybm);
+	if (!test_bit(1, mybm))
+		printk(KERN_ALERT" bit 1 tested not set\n");
+	else
+		printk(KERN_ALERT" bit 1 tested set\n");
+
+	/*
+	 * atomic version
+	 * include/asm-generic/bitops/atomic.h
+	 * arch/x86/boot/bitops.h
+	 */
+	set_bit(2, mybm);
+	if (!test_bit(2, mybm))
+		printk(KERN_ALERT" bit 2 tested not set\n");
+	else
+		printk(KERN_ALERT" bit 2 tested set\n");
+
+	clear_bit(2, mybm);
+	if (!test_bit(2, mybm))
+		printk(KERN_ALERT" bit 2 tested not set\n");
+	else
+		printk(KERN_ALERT" bit 2 tested set\n");
+
+	/* Generic API */
+	bitmap_zero(mybm, BITMAP_LEN);
+	if (!test_bit(3, mybm))
+		printk(KERN_ALERT" bit 3 tested not set\n");
+	else
+		printk(KERN_ALERT" bit 3 tested set\n");
+
+	bitmap_fill(mybm, BITMAP_LEN);
+	if (!test_bit(3, mybm))
+		printk(KERN_ALERT" bit 3 tested not set\n");
+	else
+		printk(KERN_ALERT" bit 3 tested set\n");
+
+	/* clear all before test */
+	bitmap_zero(mybm, BITMAP_LEN);
+	set_bit(4, mybm);
+	set_bit(8, mybm);
+	set_bit(9, mybm);
+	/* iterator all the setted bit */
+	for_each_set_bit(bit, mybm, BITMAP_LEN)
+		printk(KERN_ALERT" %d\n", bit);
+	printk(KERN_ALERT"===========\n");
+
+	/* iterator all the no setted bit */
+	for_each_clear_bit(bit, mybm, BITMAP_LEN)
+		printk(KERN_ALERT" %d\n", bit);
+	printk(KERN_ALERT"===========\n");
+
+	printk(KERN_ALERT"BitMap test Done\n");
+
+	return 0;
+}
+
+static void bitmap_test_exit(void)
+{
+	printk(KERN_ALERT"BitMap test Exit\n");
+}
+
+MODULE_LICENSE("Dual BSD/GPL");
+module_init(bitmap_test_init);
+module_exit(bitmap_test_exit);