source: trunk/kernel/vfs/ramfs.h @ 113

Last change on this file since 113 was 23, checked in by alain, 5 years ago

Introduce syscalls.

File size: 4.6 KB
Line 
1/*
2 * ramfs.h  RAMFS file system API definition.
3 *
4 * Authors   Mohamed Lamine Karaoui (2014,2015)
5 *           Alain Greiner (2016,2017)
6 *
7 * Copyright (c) UPMC Sorbonne Universites
8 *
9 * This file is part of ALMOS-MKH.
10 *
11 * ALMOS-MKH is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; version 2.0 of the License.
14 *
15 * ALMOS-MKH is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with ALMOS-MKH; if not, write to the Free Software Foundation,
22 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
23 */
24
25#ifndef _RAMFS_H_
26#define _RAMFS_H_
27
28///////////////////////////////////////////////////////////////////////////////////////////
29// The RAMFS File System Rdoes not uses any external device to store data.
30// It stores the dynamically created files and directories in the VFS mappers.
31// The ramfs_read_page() and ramfs_write_page() functions should never be used.
32// The RAMFS cannot be used as the root FS.
33// There is no RAMFS context extension, and no RAMFS inode extension.
34///////////////////////////////////////////////////////////////////////////////////////////
35
36
37/****  Forward declarations  ****/
38
39
40//////////////////////////////////////////////////////////////////////////////////////////
41// These functions are called by the VFS, and must be implemented by all FS.
42//////////////////////////////////////////////////////////////////////////////////////////
43
44/******************************************************************************************
45 * This function does not exist, as the RAMFS cannot be the root FS.
46 *****************************************************************************************/
47xptr_t ramfs_init();
48
49/******************************************************************************************
50 * This function mount a RAMFS on a given inode of the root FS.
51 * It actually creates a new VFS dentry in the cluster containing the parent inode,
52 * and create a new VFS inode in another cluster.
53 ******************************************************************************************
54 * @ parent_inode_xp : extended pointer on the parent inode.
55 * @ ramfs_root_name : RAMFS root directory name.
56 *****************************************************************************************/
57error_t ramfs_mount( xptr_t   parent_inode_xp,
58                     char   * ramfs_root_name );
59
60/*****************************************************************************************
61 * This function initializes all fields of the VFS context.
62 * No extra memory is allocated for a RAMFS context.
63 ****************************************************************************************/
64error_t ramfs_ctx_init( struct vfs_ctx_s * vfs_ctx,
65                        xptr_t             root_inode_xp );
66
67/*****************************************************************************************
68 * This function does not exist for a RAMFS context, as there is no RAMFS context.
69 ****************************************************************************************/
70error_t ramfs_ctx_destroy();
71
72/*****************************************************************************************
73 * This function does not exist, as the RAMFS does not use a RAMFS inode extension.
74 ****************************************************************************************/
75error_t ramfs_inode_create( struct vfs_inode_s * inode );
76
77/*****************************************************************************************
78 * This function does not exist, as the RAMFS does not use a RAMFS inode extension.
79 ****************************************************************************************/
80void ramfs_inode_destroy( struct vfs_inode_s * inode );
81
82/*****************************************************************************************
83 * This function does nothing for the RAMFS File System.
84 ****************************************************************************************/
85error_t ramfs_write_page( struct page_s * page );
86
87/*****************************************************************************************
88 * This function does not exist for the RAMFS File System.
89 ****************************************************************************************/
90error_t ramfs_read_page( struct page_s * page );
91
92
93#endif  /* _RAMFS_H_ */
Note: See TracBrowser for help on using the repository browser.