✨ 078 虚拟设备

docs/09 设备驱动/078 虚拟设备.md

@@ -0,0 +1,26 @@
+# 虚拟设备
+
+对硬件设备进行一层抽象，使得读写更加的统一，方便以后的操作。
+
+```c++
+// 安装设备
+dev_t device_install(
+    int type, int subtype,
+    void *ptr, char *name, dev_t parent,
+    void *ioctl, void *read, void *write);
+
+// 根据子类型查找设备
+device_t *device_find(int type, idx_t idx);
+
+// 根据设备号查找设备
+device_t *device_get(dev_t dev);
+
+// 控制设备
+int device_ioctl(dev_t dev, int cmd, void *args, int flags);
+
+// 读设备
+int device_read(dev_t dev, void *buf, size_t count, idx_t idx, int flags);
+
+// 写设备
+int device_write(dev_t dev, void *buf, size_t count, idx_t idx, int flags);
+```

src/include/onix/console.h

@@ -5,6 +5,5 @@
 
 void console_init();
 void console_clear();
-int32 console_write(char *buf, u32 count);
 
 #endif

src/include/onix/device.h

@@ -0,0 +1,60 @@
+#ifndef ONIX_DEVICE_H
+#define ONIX_DEVICE_H
+
+#include <onix/types.h>
+
+#define NAMELEN 16
+
+// 设备类型
+enum device_type_t
+{
+    DEV_NULL,  // 空设备
+    DEV_CHAR,  // 字符设备
+    DEV_BLOCK, // 块设备
+};
+
+// 设备子类型
+enum device_subtype_t
+{
+    DEV_CONSOLE = 1, // 控制台
+    DEV_KEYBOARD,    // 键盘
+};
+
+typedef struct device_t
+{
+    char name[NAMELEN]; // 设备名
+    int type;           // 设备类型
+    int subtype;        // 设备子类型
+    dev_t dev;          // 设备号
+    dev_t parent;       // 父设备号
+    void *ptr;          // 设备指针
+    // 设备控制
+    int (*ioctl)(void *dev, int cmd, void *args, int flags);
+    // 读设备
+    int (*read)(void *dev, void *buf, size_t count, idx_t idx, int flags);
+    // 写设备
+    int (*write)(void *dev, void *buf, size_t count, idx_t idx, int flags);
+} device_t;
+
+// 安装设备
+dev_t device_install(
+    int type, int subtype,
+    void *ptr, char *name, dev_t parent,
+    void *ioctl, void *read, void *write);
+
+// 根据子类型查找设备
+device_t *device_find(int type, idx_t idx);
+
+// 根据设备号查找设备
+device_t *device_get(dev_t dev);
+
+// 控制设备
+int device_ioctl(dev_t dev, int cmd, void *args, int flags);
+
+// 读设备
+int device_read(dev_t dev, void *buf, size_t count, idx_t idx, int flags);
+
+// 写设备
+int device_write(dev_t dev, void *buf, size_t count, idx_t idx, int flags);
+
+#endif

src/include/onix/string.h

@@ -4,6 +4,7 @@
 #include <onix/types.h>
 
 char *strcpy(char *dest, const char *src);
+char *strncpy(char *dest, const char *src, size_t count);
 char *strcat(char *dest, const char *src);
 size_t strlen(const char *str);
 int strcmp(const char *lhs, const char *rhs);

src/include/onix/types.h

@@ -40,6 +40,7 @@ typedef unsigned int u32;
 typedef unsigned long long u64;
 
 typedef int32 pid_t;
+typedef int32 dev_t;
 
 typedef u32 time_t;
 typedef u32 idx_t;

src/kernel/console.c

@@ -2,6 +2,7 @@
 #include <onix/io.h>
 #include <onix/string.h>
 #include <onix/interrupt.h>
+#include <onix/device.h>
 
 #define CRT_ADDR_REG 0x3D4 // CRT(6845)索引寄存器
 #define CRT_DATA_REG 0x3D5 // CRT(6845)数据寄存器
@@ -155,7 +156,7 @@ static void command_del()
 
 extern void start_beep();
 
-int32 console_write(char *buf, u32 count)
+int32 console_write(void *dev, char *buf, u32 count)
 {
     bool intr = interrupt_disable(); // 禁止中断
 
@@ -218,4 +219,9 @@ int32 console_write(char *buf, u32 count)
 void console_init()
 {
     console_clear();
+
+    device_install(
+        DEV_CHAR, DEV_CONSOLE,
+        NULL, "console", 0,
+        NULL, NULL, console_write);
 }

src/kernel/device.c

@@ -0,0 +1,114 @@
+#include <onix/device.h>
+#include <onix/string.h>
+#include <onix/task.h>
+#include <onix/assert.h>
+#include <onix/debug.h>
+#include <onix/arena.h>
+
+#define LOGK(fmt, args...) DEBUGK(fmt, ##args)
+
+#define DEVICE_NR 64 // 设备数量
+
+static device_t devices[DEVICE_NR]; // 设备数组
+
+// 获取空设备
+static device_t *get_null_device()
+{
+    for (size_t i = 1; i < DEVICE_NR; i++)
+    {
+        device_t *device = &devices[i];
+        if (device->type == DEV_NULL)
+            return device;
+    }
+    panic("no more devices!!!");
+}
+
+int device_ioctl(dev_t dev, int cmd, void *args, int flags)
+{
+    device_t *device = device_get(dev);
+    if (device->ioctl)
+    {
+        return device->ioctl(device->ptr, cmd, args, flags);
+    }
+    LOGK("ioctl of device %d not implemented!!!\n", dev);
+    return EOF;
+}
+
+int device_read(dev_t dev, void *buf, size_t count, idx_t idx, int flags)
+{
+    device_t *device = device_get(dev);
+    if (device->read)
+    {
+        return device->read(device->ptr, buf, count, idx, flags);
+    }
+    LOGK("read of device %d not implemented!!!\n", dev);
+    return EOF;
+}
+
+int device_write(dev_t dev, void *buf, size_t count, idx_t idx, int flags)
+{
+    device_t *device = device_get(dev);
+    if (device->write)
+    {
+        return device->write(device->ptr, buf, count, idx, flags);
+    }
+    LOGK("write of device %d not implemented!!!\n", dev);
+    return EOF;
+}
+
+// 安装设备
+dev_t device_install(
+    int type, int subtype,
+    void *ptr, char *name, dev_t parent,
+    void *ioctl, void *read, void *write)
+{
+    device_t *device = get_null_device();
+    device->ptr = ptr;
+    device->parent = parent;
+    device->type = type;
+    device->subtype = subtype;
+    strncpy(device->name, name, NAMELEN);
+    device->ioctl = ioctl;
+    device->read = read;
+    device->write = write;
+    return device->dev;
+}
+
+void device_init()
+{
+    for (size_t i = 0; i < DEVICE_NR; i++)
+    {
+        device_t *device = &devices[i];
+        strcpy((char *)device->name, "null");
+        device->type = DEV_NULL;
+        device->subtype = DEV_NULL;
+        device->dev = i;
+        device->parent = 0;
+        device->ioctl = NULL;
+        device->read = NULL;
+        device->write = NULL;
+    }
+}
+
+device_t *device_find(int subtype, idx_t idx)
+{
+    idx_t nr = 0;
+    for (size_t i = 0; i < DEVICE_NR; i++)
+    {
+        device_t *device = &devices[i];
+        if (device->subtype != subtype)
+            continue;
+        if (nr == idx)
+            return device;
+        nr++;
+    }
+    return NULL;
+}
+
+device_t *device_get(dev_t dev)
+{
+    assert(dev < DEVICE_NR);
+    device_t *device = &devices[dev];
+    assert(device->type != DEV_NULL);
+    return device;
+}

src/kernel/gate.c

@@ -5,6 +5,7 @@
 #include <onix/task.h>
 #include <onix/console.h>
 #include <onix/memory.h>
+#include <onix/device.h>
 
 #define LOGK(fmt, args...) DEBUGK(fmt, ##args)
 
@@ -27,14 +28,27 @@ static void sys_default()
 
 static u32 sys_test()
 {
+    char ch;
+    device_t *device;
+
+    device = device_find(DEV_KEYBOARD, 0);
+    assert(device);
+    device_read(device->dev, &ch, 1, 0, 0);
+
+    device = device_find(DEV_CONSOLE, 0);
+    assert(device);
+    device_write(device->dev, &ch, 1, 0, 0);
+
     return 255;
 }
 
+extern int32 console_write();
+
 int32 sys_write(fd_t fd, char *buf, u32 len)
 {
     if (fd == stdout || fd == stderr)
     {
-        return console_write(buf, len);
+        return console_write(NULL, buf, len);
     }
     // todo
     panic("write!!!!");

src/kernel/keyboard.c

@@ -5,6 +5,7 @@
 #include <onix/fifo.h>
 #include <onix/mutex.h>
 #include <onix/task.h>
+#include <onix/device.h>
 
 #define LOGK(fmt, args...) DEBUGK(fmt, ##args)
 
@@ -391,7 +392,7 @@ void keyboard_handler(int vector)
     }
 }
 
-u32 keyboard_read(char *buf, u32 count)
+u32 keyboard_read(void *dev, char *buf, u32 count)
 {
     lock_acquire(&lock);
     int nr = 0;
@@ -423,4 +424,9 @@ void keyboard_init()
 
     set_interrupt_handler(IRQ_KEYBOARD, keyboard_handler);
     set_interrupt_mask(IRQ_KEYBOARD, true);
+
+    device_install(
+        DEV_CHAR, DEV_KEYBOARD,
+        NULL, "keyboard", 0,
+        NULL, keyboard_read, NULL);
 }

src/kernel/printk.c

@@ -2,6 +2,8 @@
 #include <onix/console.h>
 #include <onix/stdio.h>
 
+extern int32 console_write();
+
 static char buf[1024];
 
 int printk(const char *fmt, ...)
@@ -15,7 +17,7 @@ int printk(const char *fmt, ...)
 
     va_end(args);
 
-    console_write(buf, i);
+    console_write(NULL, buf, i);
 
     return i;
 }

src/kernel/start.asm

@@ -17,6 +17,7 @@ header_start:
     dd 8    ; size
 header_end:
 
+extern device_init
 extern console_init
 extern gdt_init
 extern memory_init
@@ -32,6 +33,7 @@ _start:
     push ebx; ards_count
     push eax; magic
 
+    call device_init    ; 虚拟设备初始化
     call console_init   ; 控制台初始化
 
     ; xchg bx, bx

src/kernel/thread.c

@@ -62,8 +62,7 @@ void test_thread()
 
     while (true)
     {
-        // LOGK("test task %d....\n", counter++);
-        // BMB;
-        sleep(2000);
+        test();
+        // sleep(10);
     }
 }

src/lib/string.c

@@ -11,6 +11,20 @@ char *strcpy(char *dest, const char *src)
     }
 }
 
+char *strncpy(char *dest, const char *src, size_t count)
+{
+    char *ptr = dest;
+    size_t nr = 0;
+    for (; nr < count; nr++)
+    {
+        *ptr++ = *src;
+        if (*src++ == EOS)
+            return dest;
+    }
+    dest[count - 1] = EOS;
+    return dest;
+}
+
 char *strcat(char *dest, const char *src)
 {
     char *ptr = dest;

src/makefile

@@ -38,6 +38,7 @@ $(BUILD)/kernel.bin: \
 	$(BUILD)/kernel/start.o \
 	$(BUILD)/kernel/main.o \
 	$(BUILD)/kernel/io.o \
+	$(BUILD)/kernel/device.o \
 	$(BUILD)/kernel/console.o \
 	$(BUILD)/kernel/printk.o \
 	$(BUILD)/kernel/assert.o \