Courses/Computer Science/CPSC 457.W2012/Lecture Notes/VFS

= The Linux VFS and Ext4 =

The virtual file system interface sits right below Linux's implementation of the file I/O API defined by the file-related system calls. In this session, we will consider how the VFS abstracts out and supplies common operations.


 * major data structures
 * support for delegating operations to specific file system implementations
 * support for canonicalization and path lookup

The XFS file system: http://oss.sgi.com/projects/xfs/papers/xfs_usenix/index.html

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struct file

struct path

struct dentry

sys_read entry point

vfs_read