c-虚拟文件系统如何处理读写之类的系统调用

(所有代码片段都来自：https://docs.huihoo.com/doxygen/linux/kernel/3.7/dir_97b3d2b63ac216821c2d7a22ee0ab2b0.html)

嗨！为了确定我的问题，我已经研究了将近一个月的Linux fs代码，现在我被困在这里了。因此，我在include/linux/fs.h中查看了这段代码(如果我没有错的话，它包含了read_write.c和open.c等代码使用的几乎所有主要结构和指针的定义(，我观察到了以下代码片段：

struct file_operations {
1519     struct module *owner;
1520     loff_t (*llseek) (struct file *, loff_t, int);
1521     ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
1522     ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1523     ssize_t (*aio_read) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1524     ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1525     int (*readdir) (struct file *, void *, filldir_t);
1526     unsigned int (*poll) (struct file *, struct poll_table_struct *);
1527     long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
1528     long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
1529     int (*mmap) (struct file *, struct vm_area_struct *);
1530     int (*open) (struct inode *, struct file *);
1531     int (*flush) (struct file *, fl_owner_t id);
1532     int (*release) (struct inode *, struct file *);
1533     int (*fsync) (struct file *, loff_t, loff_t, int datasync);
1534     int (*aio_fsync) (struct kiocb *, int datasync);
1535     int (*fasync) (int, struct file *, int);
1536     int (*lock) (struct file *, int, struct file_lock *);
1537     ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
1538     unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1539     int (*check_flags)(int);
1540     int (*flock) (struct file *, int, struct file_lock *);
1541     ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
1542     ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1543     int (*setlease)(struct file *, long, struct file_lock **);
1544     long (*fallocate)(struct file *file, int mode, loff_t offset,
1545               loff_t len);
1546 };

正如您所看到的，他们已经定义了这些非常具体的系统调用，这些调用已经在各自的文件中声明。例如，read_write.c将其读和写系统调用的定义分别为SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count)和SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, size_t, count)。现在，出于研究目的，我基本上进入了这两个定义，找到了它们中发生的每一个函数调用(至少是Doxygen文档中链接的函数调用(，以及这些函数调用中的函数调用，但无法回答一个非常简单的问题这两个系统调用如何调用虚拟文件系统来进一步调用从文件系统读取实际数据块所需的驱动程序？(如果它是特定于文件系统的，请在代码中显示它将其交给FS驱动程序的位置(

第页。S.我对开放系统调用进行了同样的搜索，但能够找到他们调用namei.c代码的一部分来执行该任务的位置，特别是在这里：struct file *do_filp_open(int dfd, struct filename *pathname, const struct open_flags *op, int flags)。在这里，它们使用具有inode中的相关信息的结构nameidata来打开文件。