The following entry points are specified by the virtual file system interface for performing operations on vfs structures:
| Entry Point | Description | 
|---|---|
| vfs_aclxcntl | Issues ACL related control operations for a file system. | 
| vfs_cntl | Issues control operations for a file system. | 
| vfs_init | Initializes a virtual file system. | 
| vfs_mount | Mounts a virtual file system. | 
| vfs_root | Finds the root v-node of a virtual file system. | 
| vfs_statfs | Obtains virtual file system statistics. | 
| vfs_sync | Forces file system updates to permanent storage. | 
| vfs_umount | Unmounts a virtual file system. | 
| vfs_vget | Gets the v-node corresponding to a file identifier. | 
The following entry points are specified by the Virtual File System interface for performing operations on v-node structures:
| Entry Point | Description | 
|---|---|
| vnop_access | Tests a user's permission to access a file. | 
| vnop_close | Releases the resources associated with a v-node. | 
| vnop_create | Creates and opens a new file. | 
| vnop_create_attr | Creates and opens a new file with initial attributes. | 
| vnop_fclear | Releases portions of a file (by zeroing bytes). | 
| vnop_fid | Builds a file identifier for a v-node. | 
| vnop_finfo | Returns pathconf information about a file or file system. | 
| vnop_fsync | Flushes in-memory information and data to permanent storage. | 
| vnop_fsync_range | Flushes in-memory information and data for a given range to permanent storage. | 
| vnop_ftrunc | Decreases the size of a file. | 
| vnop_getacl | Gets information about access control, by retrieving the access control list. | 
| vnop_getattr | Gets the attributes of a file. | 
| vnop_getxacl | Gets information about access control by retrieving the ACL. Provides an advanced interface when compared to vnop_getacl. | 
| vnop_hold | Assures that a v-node is not destroyed, by incrementing the v-node's use count. | 
| vnop_ioctl | Performs miscellaneous operations on devices. | 
| vnop_link | Creates a new directory entry for a file. | 
| vnop_lockctl | Sets, removes, and queries file locks. | 
| vnop_lookup | Finds an object by name in a directory. | 
| vnop_map | Associates a file with a memory segment. | 
| vnop_map_lloff | Associates a file with a memory segment using 64 bit offset. | 
| vnop_memcntl | Manages physical attachment of a file. | 
| vnop_mkdir | Creates a directory. | 
| vnop_mknod | Creates a file of arbitrary type. | 
| vnop_open | Gets read and/or write access to a file. | 
| vnop_rdwr | Reads or writes a file. | 
| vnop_rdwr_attr | Reads or writes a file and returns attributes. | 
| vnop_readdir | Reads directory entries in standard format. | 
| vnop_readdir_eofp | Reads directories and returns end of file indication. | 
| vnop_readlink | Reads the contents of a symbolic link. | 
| vnop_rele | Releases a reference to a virtual node (v-node). | 
| vnop_remove | Unlinks a file or directory. | 
| vnop_rename | Renames a file or directory. | 
| vnop_revoke | Revokes access to an object. | 
| vnop_rmdir | Removes a directory. | 
| vnop_seek | Moves the current offset in a file. | 
| vnop_select | Polls a v-node for pending I/O. | 
| vnop_setacl | Sets information about access control for a file. | 
| vnop_setattr | Sets attributes of a file. | 
| vnop_setxacl | Sets information about access control for a file. Provides an advanced interface compared to vnop_setacl. | 
| vnop_strategy | Reads or writes blocks of a file. | 
| vnop_symlink | Creates a symbolic link. | 
| vnop_unmap | Destroys a file or memory association. | 
Virtual File System Kernel Extensions Overview.
Understanding Virtual Nodes (V-nodes).