对文件系统 磁盘,分区描述符的注释

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compat/posix/src/socket.c

@@ -35,8 +35,12 @@
 
 #ifdef LOSCFG_NET_LWIP_SACK
 #include <lwip/sockets.h>
+/*****************************************************
+* posix socket标准接口，对 lwip协议族适配封装层
+*****************************************************/
 
-#if !LWIP_COMPAT_SOCKETS
+#if !LWIP_COMPAT_SOCKETS 
+//检查空指针,注意 do while(0)的妙用，想想这样写的好处是什么？
 #define CHECK_NULL_PTR(ptr) do { if (ptr == NULL) { set_errno(EFAULT); return -1; } } while (0)
 //接受连接 
 int accept(int s, struct sockaddr *addr, socklen_t *addrlen)
@@ -97,7 +101,7 @@ int connect(int s, const struct sockaddr *name, socklen_t namelen)
     }
     return lwip_connect(s, name, namelen);
 }
-//监听本socket的请求
+//监听socket的请求
 int listen(int s, int backlog)
 {
     return lwip_listen(s, backlog);
@@ -146,7 +150,13 @@ ssize_t sendto(int s, const void *dataptr, size_t size, int flags,
     }
     return lwip_sendto(s, dataptr, size, flags, to, tolen);
 }
-//	创建socket
+/*********************************************************
+posix 之创建socket 
+domain:	协议族名字 如 AF_INET 为 IPv4 
+type:	指示类型
+protocol:
+返回FD
+*********************************************************/
 int socket(int domain, int type, int protocol)
 {
     return lwip_socket(domain, type, protocol);

fs/include/disk.h

@@ -165,49 +165,49 @@ extern "C" {
 #define DISK_ATA_GET_MODEL      21  /* Get model name */
 #define DISK_ATA_GET_SN         22  /* Get serial number */
 
-typedef enum _disk_status_ {
-    STAT_UNUSED,
-    STAT_INUSED,
-    STAT_UNREADY
+typedef enum _disk_status_ {//磁盘的状态
+    STAT_UNUSED,	//未使用
+    STAT_INUSED,	//使用中
+    STAT_UNREADY	//未准备,可理解为未格式化
 } disk_status_e;
 
-typedef struct _los_disk_ {
-    UINT32 disk_id : 8;     /* physics disk number */
-    UINT32 disk_status : 2; /* status of disk */
-    UINT32 part_count : 8;  /* current partition count */
-    UINT32 reserved : 14;
+typedef struct _los_disk_ {	//磁盘描述符
+    UINT32 disk_id : 8;     /* physics disk number */ 	//标识磁盘ID
+    UINT32 disk_status : 2; /* status of disk */		//磁盘的状态 disk_status_e
+    UINT32 part_count : 8;  /* current partition count */	//分了多少个区(los_part)
+    UINT32 reserved : 14;	//保留，注意 disk_id|disk_status|part_count|reserved 共用一个UINT32				
     struct inode *dev;      /* device */
-#ifdef LOSCFG_FS_FAT_CACHE
+#ifdef LOSCFG_FS_FAT_CACHE	//磁盘缓存，在所有分区中共享
     OsBcache *bcache;       /* cache of the disk, shared in all partitions */
 #endif
-    UINT32 sector_size;     /* disk sector size */
-    UINT64 sector_start;    /* disk start sector */
-    UINT64 sector_count;    /* disk sector number */
-    UINT8 type;
-    CHAR *disk_name;
-    LOS_DL_LIST head;       /* link head of all the partitions */
+    UINT32 sector_size;     /* disk sector size */	//扇区大小
+    UINT64 sector_start;    /* disk start sector */	//开始扇区
+    UINT64 sector_count;    /* disk sector number *///扇区数量	
+    UINT8 type;				//flash的类型 例如:EMMC
+    CHAR *disk_name;		//设备名称
+    LOS_DL_LIST head;       /* link head of all the partitions */ //双向链表上挂所有分区(los_part->list)
     struct pthread_mutex disk_mutex;
 } los_disk;
 
-typedef struct _los_part_ {
-    UINT32 disk_id : 8;      /* physics disk number */
-    UINT32 part_id : 8;      /* partition number in the system */
-    UINT32 part_no_disk : 8; /* partition number in the disk */
-    UINT32 part_no_mbr : 5;  /* partition number in the mbr */
-    UINT32 reserved : 3;
-    UINT8 filesystem_type;   /* filesystem used in the partition */
-    UINT8 type;
-    struct inode *dev;      /* dev devices used in the partition */
-    CHAR *part_name;
-    UINT64 sector_start;     /*
+typedef struct _los_part_ {//分区描述符
+    UINT32 disk_id : 8;      /* physics disk number */	//标识磁盘ID
+    UINT32 part_id : 8;      /* partition number in the system */ //标识整个系统的分区ID
+    UINT32 part_no_disk : 8; /* partition number in the disk */	  //标识所属磁盘的分区ID
+    UINT32 part_no_mbr : 5;  /* partition number in the mbr */	  //硬盘主引导记录（即Master Boot Record，一般简称为MBR），主分区ID	
+    UINT32 reserved : 3;	////保留，注意 disk_id|part_id|part_no_disk|part_no_mbr|reserved 共用一个UINT32
+    UINT8 filesystem_type;   /* filesystem used in the partition */ //文件系统类型
+    UINT8 type;				//flash的类型 例如:EMMC
+    struct inode *dev;      /* dev devices used in the partition */ //分区所使用的dev设备
+    CHAR *part_name;		//区名称
+    UINT64 sector_start;     /* //开始扇区编号
                               * offset of a partition to the primary devices
                               * (multi-mbr partitions are seen as same parition)
                               */
-    UINT64 sector_count;     /*
+    UINT64 sector_count;     /*	//扇区数量
                               * sector numbers of a partition. If there is no addpartition operation,
                               * then all the mbr devices equal to the primary device count.
                               */
-    LOS_DL_LIST list;        /* linklist of partition */
+    LOS_DL_LIST list;        /* linklist of partition */ //通过它挂到los_disk->head上
 } los_part;
 
 struct partition_info {

fs/include/fs/fd_table.h

@@ -85,6 +85,6 @@ struct files_struct *create_files_snapshot(const struct files_struct *oldf);//
 
 void delete_files_snapshot(struct files_struct *files);//删除文件管理器快照
 
-int alloc_fd(int minfd);//分配一个fd，当然是从files_struct->fdt 数组中拿一个未被使用(分配)的fd，默认都是 -1
+int alloc_fd(int minfd);//分配一个fd，从files_struct->fdt 数组中拿一个未被使用(分配)的fd，默认都是 -1
 
 #endif

fs/vfs/disk/disk.c

@@ -48,13 +48,13 @@ extern "C" {
 #endif /* __cplusplus */
 #endif /* __cplusplus */
 
-los_disk g_sysDisk[SYS_MAX_DISK];
-los_part g_sysPart[SYS_MAX_PART];
+los_disk g_sysDisk[SYS_MAX_DISK];//支持挂载的磁盘总数量 5个
+los_part g_sysPart[SYS_MAX_PART];//支持磁盘的分区总数量 5*16,每个磁盘最大分16个区
 
-UINT32 g_uwFatSectorsPerBlock = CONFIG_FS_FAT_SECTOR_PER_BLOCK;
-UINT32 g_uwFatBlockNums = CONFIG_FS_FAT_BLOCK_NUMS;
+UINT32 g_uwFatSectorsPerBlock = CONFIG_FS_FAT_SECTOR_PER_BLOCK; //每块支持扇区数 默认64个扇区
+UINT32 g_uwFatBlockNums = CONFIG_FS_FAT_BLOCK_NUMS;	//块数量 默认28
 
-spinlock_t g_diskSpinlock;
+spinlock_t g_diskSpinlock;	//磁盘自锁锁
 spinlock_t g_diskFatBlockSpinlock;
 
 UINT32 g_usbMode = 0;
@@ -216,7 +216,7 @@ static BOOL GetDiskUsbStatus(UINT32 diskID)
     return (g_usbMode & (1u << diskID)) ? TRUE : FALSE;
 }
 #endif
-
+//获取某个磁盘的描述符
 los_disk *get_disk(INT32 id)
 {
     if ((id >= 0) && (id < SYS_MAX_DISK)) {
@@ -225,7 +225,7 @@ los_disk *get_disk(INT32 id)
 
     return NULL;
 }
-
+//获取某个分区的描述符
 los_part *get_part(INT32 id)
 {
     if ((id >= 0) && (id < SYS_MAX_PART)) {
@@ -1279,40 +1279,46 @@ static VOID OsDiskInitSub(const CHAR *diskName, INT32 diskID, los_disk *disk,
     disk->bcache = bc;
 #endif
 
-    (VOID)pthread_mutexattr_init(&attr);
-    attr.type = PTHREAD_MUTEX_RECURSIVE;
-    (VOID)pthread_mutex_init(&disk->disk_mutex, &attr);
+    (VOID)pthread_mutexattr_init(&attr);//posix 互斥量属性初始化
+    attr.type = PTHREAD_MUTEX_RECURSIVE;//使用递归型互斥，鸿蒙内核为降低死锁概率 默认就是递归方式
+    (VOID)pthread_mutex_init(&disk->disk_mutex, &attr);//初始化磁盘的互斥量
 
-    DiskStructInit(diskName, diskID, diskInfo, blkDriver, disk);
+    DiskStructInit(diskName, diskID, diskInfo, blkDriver, disk);//初始化磁盘描述符los_disk
 }
-
+/***************************************************************
+磁盘初始化 , diskName 必须是 /dev/***
+当块设备注册到系统。它被文件系统用来执行文件系统处理。它可以处理struct inode
+inode:索引节点对象，存放关于具体文件的一般信息，每个索引节点对象都有一个索引节点号
+	  这个节点号唯一地标识文件系统中的文件
+geometry block_operations:	见于../../../../../third_party/NuttX/include/nuttx/fs/fs.h
+***************************************************************/
 INT32 los_disk_init(const CHAR *diskName, const struct block_operations *bops,
                     VOID *priv, INT32 diskID, VOID *info)
 {
-    struct geometry diskInfo;
+    struct geometry diskInfo;	//此结构提供有关块驱动程序状态的信息
     struct inode *blkDriver = NULL;
     los_disk *disk = get_disk(diskID);
-    struct inode_search_s desc;
+    struct inode_search_s desc;//见于 ../../../../../third_party/NuttX/fs/inode/inode.h
     INT32 ret;
 
-    if ((diskName == NULL) || (disk == NULL) ||
+    if ((diskName == NULL) || (disk == NULL) || //磁盘不能是未准备好状态
         (disk->disk_status != STAT_UNREADY) || (strlen(diskName) > DISK_NAME)) {
         return VFS_ERROR;
     }
-
-    if (register_blockdriver(diskName, bops, RWE_RW_RW, priv) != 0) {
+	//详见 \third_party\NuttX\fs\driver\fs_registerblockdriver.c
+    if (register_blockdriver(diskName, bops, RWE_RW_RW, priv) != 0) {//1.在伪文件系统中注册块驱动程序，注册之后可以对其进行操作
         PRINT_ERR("disk_init : register %s fail!\n", diskName);
         return VFS_ERROR;
     }
 
-    SETUP_SEARCH(&desc, diskName, false);
-    ret = inode_find(&desc);
+    SETUP_SEARCH(&desc, diskName, false);//是个赋值宏操作 desc.path     = diskName;
+    ret = inode_find(&desc);//2.更新desc.node
     if (ret < 0) {
         PRINT_ERR("disk_init : find %s fail!\n", diskName);
         ret = ENOENT;
         goto DISK_FIND_ERROR;
     }
-    blkDriver = desc.node;
+    blkDriver = desc.node;//
 
     if ((blkDriver->u.i_bops == NULL) || (blkDriver->u.i_bops->geometry == NULL) ||
         (blkDriver->u.i_bops->geometry(blkDriver, &diskInfo) != 0)) {
@@ -1324,7 +1330,7 @@ INT32 los_disk_init(const CHAR *diskName, const struct block_operations *bops,
 
     PRINTK("disk_init : register %s ok!\n", diskName);
 
-    OsDiskInitSub(diskName, diskID, disk, &diskInfo, blkDriver);
+    OsDiskInitSub(diskName, diskID, disk, &diskInfo, blkDriver);//3.初始化los_disk
     inode_release(blkDriver);
 
     if (DiskDivideAndPartitionRegister(info, disk) != ENOERR) {
@@ -1347,7 +1353,7 @@ DISK_FIND_ERROR:
     (VOID)unregister_blockdriver(diskName);
     return VFS_ERROR;
 }
-
+//磁盘去初始化，和los_disk_init成对出现，类似于 C++ 的构造<->析构函数
 INT32 los_disk_deinit(INT32 diskID)
 {
     los_disk *disk = get_disk(diskID);

fs/vfs/operation/fs_file.c

@@ -126,7 +126,7 @@ int CheckProcessFd(int procFd)
 
     return OK;
 }
-
+//分配一个系统文件描述符
 int GetAssociatedSystemFd(int procFd)
 {
     struct fd_table_s *fdt = GetFdTable();

kernel/common/los_rootfs.c

@@ -60,7 +60,7 @@ extern "C" {
 
 #ifdef LOSCFG_PLATFORM_HI3516DV300
 #define STORAGE_SIZE 0x3200000
-STATIC los_disk *g_emmcDisk = NULL;
+STATIC los_disk *g_emmcDisk = NULL; 
 #endif
 
 #ifndef LOSCFG_SECURITY_BOOT
@@ -369,7 +369,7 @@ ERROUT:
 #endif
 
 #ifdef LOSCFG_PLATFORM_HI3516DV300
-STATIC VOID OsMountUserdata(const CHAR *fsType)
+STATIC VOID OsMountUserdata(const CHAR *fsType)//mount emmc /userdata
 {
     INT32 ret;
     INT32 err;
@@ -413,26 +413,26 @@ STATIC INT32 OsMountRootfsAndUserfs(const CHAR *rootDev, const CHAR *fsType)
 {
     INT32 ret;
     INT32 err;
-    if (strcmp(fsType, "vfat") == 0) {
-        ret = mount(rootDev, "/", fsType, MS_RDONLY, NULL);
+    if (strcmp(fsType, "vfat") == 0) { //vfat 格式处理  VFAT (Virtual File Allocation Table) 虚拟文件分配表
+        ret = mount(rootDev, "/", fsType, MS_RDONLY, NULL);// mount /
         if (ret != LOS_OK) {
             err = get_errno();
             PRINT_ERR("Failed to mount vfat rootfs, errno %d: %s\n", err, strerror(err));
             return ret;
         }
-        g_root_inode->i_mode |= S_IRWXU | S_IRWXG | S_IRWXO;
+        g_root_inode->i_mode |= S_IRWXU | S_IRWXG | S_IRWXO; // 777
 #ifdef LOSCFG_PLATFORM_HI3516DV300
-        ret = mkdir("/storage", VFAT_STORAGE_MOUNT_DIR_MODE);
+        ret = mkdir("/storage", VFAT_STORAGE_MOUNT_DIR_MODE); //根目录下创建storage目录
         if (ret != LOS_OK) {
             err = get_errno();
             PRINT_ERR("Failed to reserve inode /storage, errno %d: %s\n", err, strerror(err));
-        } else {
+        } else { 
             CHAR emmcStorageDev[DISK_NAME] = {0};
             if (snprintf_s(emmcStorageDev, sizeof(emmcStorageDev), sizeof(emmcStorageDev) - 1,
                 "%s%s", g_emmcDisk->disk_name, "p1") < 0) {
                 PRINT_ERR("Failed to get emmc storage dev name!\n");
             } else {
-                ret = mount(emmcStorageDev, "/storage", fsType, 0, "umask=000");
+                ret = mount(emmcStorageDev, "/storage", fsType, 0, "umask=000");//挂载storage目录
                 if (ret != LOS_OK) {
                     err = get_errno();
                     PRINT_ERR("Failed to mount /storage, errno %d: %s\n", err, strerror(err));
@@ -441,7 +441,7 @@ STATIC INT32 OsMountRootfsAndUserfs(const CHAR *rootDev, const CHAR *fsType)
         }
         OsMountUserdata(fsType);
 #endif
-    } else {
+    } else { //非 vfat格式
         ret = mount(rootDev, "/", fsType, MS_RDONLY, NULL);
         if (ret != LOS_OK) {
             err = get_errno();
@@ -454,7 +454,7 @@ STATIC INT32 OsMountRootfsAndUserfs(const CHAR *rootDev, const CHAR *fsType)
             err = get_errno();
             PRINT_ERR("Failed to reserve inode /storage, errno %d: %s\n", err, strerror(err));
         } else {
-            ret = mount(DEV_STORAGE_PATH, "/storage", fsType, 0, NULL);
+            ret = mount(DEV_STORAGE_PATH, "/storage", fsType, 0, NULL);//挂载storage目录
             if (ret != LOS_OK) {
                 err = get_errno();
                 PRINT_ERR("Failed to mount /storage, errno %d: %s\n", err, strerror(err));
@@ -464,7 +464,11 @@ STATIC INT32 OsMountRootfsAndUserfs(const CHAR *rootDev, const CHAR *fsType)
     }
     return LOS_OK;
 }
-
+/******************************************************
+	挂载根文件系统 分两个阶段
+1.文件系统提供一个作为初始安装点的空目录
+2.内核在空目录上安装根文件系统
+******************************************************/
 INT32 OsMountRootfs(VOID)
 {
     INT32 ret = LOS_OK;
@@ -489,9 +493,9 @@ INT32 OsMountRootfs(VOID)
     rootSize = (rootSize >= 0) ? rootSize : ROOTFS_FLASH_SIZE;
 #endif
 
-    rootDev = GetDevName(rootType, rootAddr, rootSize);
+    rootDev = GetDevName(rootType, rootAddr, rootSize);//获取根设备 /dev/***
     if (rootDev != NULL) {
-        ret = OsMountRootfsAndUserfs(rootDev, fsType);
+        ret = OsMountRootfsAndUserfs(rootDev, fsType);//将根设备挂到 /下， 
         if (ret != LOS_OK) {
             err = get_errno();
             PRINT_ERR("Failed to mount rootfs, errno %d: %s\n", err, strerror(err));

kernel/common/los_rootfs.h

@@ -32,20 +32,20 @@
 #ifndef _LOS_ROOTFS_H
 #define _LOS_ROOTFS_H
 
-#define BYTES_PER_MBYTE         0x100000
-#define BYTES_PER_KBYTE         0x400
+#define BYTES_PER_MBYTE         0x100000	//1M = 1024 * 1024
+#define BYTES_PER_KBYTE         0x400		//1K = 1024
 
 #define COMMAND_LINE_ADDR       512 * BYTES_PER_KBYTE
 #define COMMAND_LINE_SIZE       1024
 
-#ifdef LOSCFG_PLATFORM_HI3518EV300
-#define ROOTFS_ROOT_TYPE        "flash"
-#define ROOTFS_FS_TYPE          "jffs2"
+#ifdef LOSCFG_PLATFORM_HI3518EV300 
+#define ROOTFS_ROOT_TYPE        "flash"	//根文件系统存放在哪种设备上，这里是flash
+#define ROOTFS_FS_TYPE          "jffs2" //3518 平台使用根文件系统的类型 
 #endif
 
 #ifdef LOSCFG_PLATFORM_HI3516DV300
-#define ROOTFS_ROOT_TYPE        "emmc"
-#define ROOTFS_FS_TYPE          "vfat"
+#define ROOTFS_ROOT_TYPE        "emmc"	//eMMC=NAND闪存+闪存控制芯片+标准接口封装 https://blog.csdn.net/xjw1874/article/details/81505967
+#define ROOTFS_FS_TYPE          "vfat" 	//3516 平台使用根文件系统的类型 
 #endif
 
 #ifdef LOSCFG_TEE_ENABLE
@@ -56,8 +56,8 @@
 #define ROOTFS_FLASH_SIZE       0xa00000
 #endif
 
-#define FLASH_TYPE              "spinor"
-#define FLASH_DEV_NAME          "/dev/spinorblk0"
+#define FLASH_TYPE              "spinor" //flash类型
+#define FLASH_DEV_NAME          "/dev/spinorblk0" //根文件系统路径
 
 #define EMMC_SEC_SIZE           512
 

syscall/net_syscall.c

@@ -259,7 +259,7 @@ static void *DupUserMem(const void *ptr, size_t len, int needCopy)
         ptr##arr->arr = ptr##cpybak.arr; \
         ptr##cpybak.arr = tmp; \
     }
-
+//系统调用之socket
 int SysSocket(int domain, int type, int protocol)
 {
     int ret;
@@ -272,7 +272,7 @@ int SysSocket(int domain, int type, int protocol)
     SOCKET_K2U(ret);
     return ret;
 }
-
+//系统调用之绑定
 int SysBind(int s, const struct sockaddr *name, socklen_t namelen)
 {
     int ret;

zzz/git/push.sh

 git add -A
-git commit -m  '从ifconfig netstat 等常用网络命令的实现来理解lwip协议栈 
+git commit -m  '对文件系统 磁盘,分区描述符的注释
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 搜索 @note_why 是注者尚未看明白的地方，如果您看明白了，请告诉注者完善
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