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