Mastering Linux Kernel Development

File open and close operations

When a user process attempts to open a file, it invokes the open operation of the filesystem with appropriate arguments, which include path and name of the file. The filesystem traverses through directories specified in the path until it reaches the immediate parent directory that contains the requested file's record. Lookup into the file record produces the inode number of the specified file. However, specific logic and efficiency of lookup operation depends on the data structure chosen by the particular filesystem implementation for organizing file records in a directory block.

Once the filesystem retrieves the related inode number of the file, it initiates appropriate sanity checks to enforce access control ...