1 | /* |
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2 | * vfs.h - Virtual File System definition. |
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3 | * |
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4 | * Author Mohamed Lamine Karaoui (2014,2015) |
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5 | * Alain Greiner (2016,2017,2018,2019,2020) |
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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 _VFS_H_ |
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26 | #define _VFS_H_ |
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27 | |
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28 | #include <kernel_config.h> |
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29 | #include <hal_kernel_types.h> |
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30 | #include <hal_atomic.h> |
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31 | #include <remote_rwlock.h> |
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32 | #include <remote_busylock.h> |
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33 | #include <busylock.h> |
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34 | #include <list.h> |
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35 | #include <xlist.h> |
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36 | #include <bits.h> |
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37 | #include <xhtab.h> |
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38 | #include <errno.h> |
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39 | #include <shared_syscalls.h> |
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40 | #include <fatfs.h> |
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41 | #include <ramfs.h> |
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42 | #include <devfs.h> |
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43 | #include <dev_ioc.h> |
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44 | |
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45 | /**** Forward declarations ***/ |
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46 | |
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47 | struct vfs_inode_s; |
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48 | struct vfs_dentry_s; |
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49 | struct vfs_ctx_s; |
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50 | struct vfs_file_s; |
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51 | struct remote_buf_s; |
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52 | struct mapper_s; |
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53 | struct process_s; |
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54 | struct device_s; |
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55 | struct vseg_s; |
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56 | struct page_s; |
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57 | struct ksock_s; |
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58 | |
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59 | /****************************************************************************************** |
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60 | * These flags are used to define the working mode of the vfs_lookup() function. |
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61 | *****************************************************************************************/ |
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62 | |
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63 | #define VFS_LOOKUP_DIR 0x01 /* the searched inode must be a directory */ |
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64 | #define VFS_LOOKUP_OPEN 0x02 /* the search is for an open/opendir */ |
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65 | #define VFS_LOOKUP_PARENT 0x04 /* return the parent inode (not the inode itself) */ |
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66 | #define VFS_LOOKUP_CREATE 0x10 /* file must be created if missing */ |
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67 | #define VFS_LOOKUP_EXCL 0x20 /* file cannot previously exist */ |
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68 | |
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69 | |
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70 | |
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71 | |
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72 | /****************************************************************************************** |
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73 | * This structure defines a VFS context, that contains informations common to all inodes |
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74 | * and dentries for a given file system. As it is declared as a global variable in the |
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75 | * kdata segment (fs_context[] array), it is replicated in all clusters. |
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76 | * The <extend> field is a pointer on the FS specific context extension. |
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77 | * This extension is dynamically allocated by kernel_init in all clusters. |
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78 | * In each cluster, the inum allocator can be accessed by any thread runing |
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79 | * in any cluster, and is therefore protected by a remote_busylock. |
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80 | *****************************************************************************************/ |
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81 | |
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82 | typedef enum |
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83 | { |
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84 | FS_TYPE_RAMFS = 0, |
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85 | FS_TYPE_DEVFS = 1, |
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86 | FS_TYPE_FATFS = 2, |
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87 | |
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88 | FS_TYPES_NR = 3, |
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89 | } |
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90 | vfs_fs_type_t; |
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91 | |
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92 | typedef enum |
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93 | { |
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94 | CTX_ATTR_READ_ONLY = 0x01, /*! write access prohibited */ |
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95 | CTX_ATTR_SYNC = 0x10, /*! synchronise FS on each write */ |
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96 | } |
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97 | vfs_ctx_attr_t; |
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98 | |
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99 | typedef struct vfs_ctx_s |
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100 | { |
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101 | vfs_fs_type_t type; /*! File System type */ |
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102 | uint32_t total_clusters; /*! total number of clusters on device */ |
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103 | uint32_t cluster_size; /*! cluster size on device (bytes) */ |
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104 | xptr_t vfs_root_xp; /*! extended pointer on VFS root inode */ |
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105 | remote_busylock_t lock; /*! lock protecting inum allocator */ |
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106 | uint32_t bitmap[BITMAP_SIZE(CONFIG_VFS_MAX_INODES)]; /* inum allocator */ |
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107 | void * extend; /*! FS specific context extension */ |
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108 | } |
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109 | vfs_ctx_t; |
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110 | |
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111 | /****************************************************************************************** |
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112 | * These functions access / modify a VFS context. |
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113 | *****************************************************************************************/ |
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114 | |
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115 | /****************************************************************************************** |
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116 | * This function initialises a (statically allocated) VFS context in cluster identified |
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117 | * by the <cxy> argument. |
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118 | * It is called by the kernel_init() function. |
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119 | ****************************************************************************************** |
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120 | * @ cxy : target cluster identifier. |
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121 | * @ fs_type : file system type. |
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122 | * @ total_clusters : total number of clusters on device. |
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123 | * @ cluster_size : cluster size on device (bytes). |
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124 | * @ vfs_root_xp : extended pointer on VFS root inode. |
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125 | * @ extend : fs_type_specific extension. |
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126 | *****************************************************************************************/ |
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127 | void vfs_ctx_init( cxy_t cxy, |
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128 | vfs_fs_type_t type, |
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129 | uint32_t total_clusters, |
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130 | uint32_t cluster_size, |
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131 | xptr_t vfs_root_xp, |
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132 | void * extend ); |
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133 | |
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134 | /****************************************************************************************** |
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135 | * This function allocates an inode identifier from the local cluster inum allocator. |
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136 | * The inum respects a fixed format: |
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137 | * - the 16 MSB bits contain the cluster identifier : cxy |
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138 | * - the 16 LSB bits contains the local inode identifier : lid |
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139 | ****************************************************************************************** |
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140 | * @ ctx_xp : [in] extended pointer on file system context. |
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141 | * @ inum : [out] buffer for allocated inode identifier. |
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142 | * @ return 0 if success / return non-zero if error. |
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143 | *****************************************************************************************/ |
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144 | error_t vfs_ctx_inum_alloc( xptr_t ctx_xp, |
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145 | uint32_t * inum ); |
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146 | |
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147 | /****************************************************************************************** |
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148 | * This function release an inode identifier. |
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149 | ****************************************************************************************** |
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150 | * @ ctx_xp : [in] extended pointer on file system context. |
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151 | * @ inum : [in] released inode identifier. |
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152 | *****************************************************************************************/ |
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153 | void vfs_ctx_inum_release( xptr_t ctx_xp, |
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154 | uint32_t inum ); |
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155 | |
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156 | |
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157 | |
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158 | |
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159 | |
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160 | |
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161 | /****************************************************************************************** |
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162 | * This file structure describes an open file/directory for a given process. |
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163 | * It is not replicated, and is dynamically allocated in the cluster that contains |
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164 | * the associated inode / socket / pipe , when a thread makes an open(), opendir(), |
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165 | * socket(), or pipe() system call. It cannot exist a <file> structure without a |
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166 | * a <mapper>, <socket>, or <pipe> structure (depending on type) in same cluster. |
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167 | * It can exist a <file> structure without an <inode> (for PIPE and SOCK types). |
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168 | *****************************************************************************************/ |
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169 | |
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170 | /* this enum define the VFS file types */ |
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171 | /* WARNING : this enum must be kept consistent with macros in <shared_stat.h> file */ |
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172 | /* and with types in <shared_dirent.h> file. */ |
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173 | |
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174 | typedef enum |
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175 | { |
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176 | FILE_TYPE_REG = 0, /*! regular file */ |
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177 | FILE_TYPE_DIR = 1, /*! directory */ |
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178 | FILE_TYPE_FIFO = 2, /*! POSIX named fifo */ |
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179 | FILE_TYPE_PIPE = 3, /*! POSIX anonymous pipe */ |
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180 | FILE_TYPE_SOCK = 4, /*! POSIX anonymous socket */ |
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181 | FILE_TYPE_DEV = 5, /*! character device */ |
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182 | FILE_TYPE_BLK = 6, /*! block device */ |
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183 | FILE_TYPE_SYML = 7, /*! symbolic link */ |
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184 | } |
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185 | vfs_file_type_t; |
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186 | |
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187 | typedef enum |
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188 | { |
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189 | FD_ATTR_READ_ENABLE = 0x01, /*! read access possible */ |
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190 | FD_ATTR_WRITE_ENABLE = 0x02, /*! write access possible */ |
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191 | FD_ATTR_APPEND = 0x04, /*! append on each write */ |
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192 | FD_ATTR_CLOSE_EXEC = 0x08, /*! close file on exec */ |
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193 | FD_ATTR_SYNC = 0x10, /*! synchronise FS on each write */ |
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194 | FD_ATTR_IS_DIR = 0x20, /*! this is a directory */ |
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195 | } |
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196 | vfs_file_attr_t; |
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197 | |
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198 | typedef struct vfs_file_s |
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199 | { |
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200 | struct vfs_ctx_s * ctx; /*! local pointer on FS context. */ |
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201 | vfs_file_attr_t attr; /*! file attributes bit vector (see above) */ |
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202 | vfs_file_type_t type; /*! same type as inode */ |
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203 | uint32_t offset; /*! seek position in file */ |
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204 | remote_rwlock_t lock; /*! protect offset modifications */ |
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205 | struct vfs_inode_s * inode; /*! local pointer on associated inode */ |
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206 | struct mapper_s * mapper; /*! associated mapper (REG or DIR types only) */ |
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207 | struct socket_s * socket; /*! associated socket (SOCK type only) */ |
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208 | struct pipe_s * pipe; /*! associated pipe (FIFO or PIPE types only) */ |
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209 | void * extend; /*! FS specific extension */ |
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210 | } |
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211 | vfs_file_t; |
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212 | |
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213 | /****************************************************************************************** |
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214 | * These low-level functions access / modify a VFS file descriptor |
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215 | *****************************************************************************************/ |
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216 | |
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217 | /****************************************************************************************** |
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218 | * This function allocates memory and initializes a new file descriptor in the |
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219 | * cluster defined by the <inode_xp> argument. |
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220 | * It can be called by any thread running in any cluster. |
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221 | ****************************************************************************************** |
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222 | * @ inode_xp : [in] extended pointer on associated inode. |
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223 | * @ attr : [in] file descriptor attributes. |
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224 | * @ file_xp : [out] buffer for extended pointer on created file descriptor. |
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225 | * @ return 0 if success / return ENOMEM if error. |
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226 | *****************************************************************************************/ |
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227 | error_t vfs_file_create( xptr_t inode_xp, |
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228 | uint32_t attr, |
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229 | xptr_t * file_xp ); |
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230 | |
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231 | /****************************************************************************************** |
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232 | * This function releases memory allocated to file descriptor identified |
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233 | * by the <file_xp> argument. |
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234 | * It can be called by any thread running in any cluster. |
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235 | ****************************************************************************************** |
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236 | * @ file_xp : [in] extended pointer on file descriptor. |
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237 | *****************************************************************************************/ |
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238 | void vfs_file_destroy( xptr_t file_xp ); |
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239 | |
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240 | /****************************************************************************************** |
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241 | * This debug function copies the name of a the file identified by <file_xp> |
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242 | * argument to a local buffer identified by the <name> argument. |
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243 | * The local buffer size must be at least CONFIG_VFS_MAX_NAME_LENGTH. |
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244 | ***************************************************************************************** |
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245 | * @ ionde_xp : [in] extended pointer on the remote inode. |
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246 | * @ name : [out] local string. |
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247 | ***************************************************************************************/ |
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248 | void vfs_file_get_name( xptr_t inode_xp, |
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249 | char * name ); |
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250 | |
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251 | |
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252 | |
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253 | |
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254 | /****************************************************************************************** |
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255 | * This structure define a VFS inode. |
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256 | * An inode can have several children dentries (if it is a directory), an can have several |
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257 | * parents dentries (if it has several aliases links): |
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258 | * - The "parents" field is the root of the xlist of parents dentries, and the "links" |
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259 | * fiels define the number of aliases parent dentries. only a FILE inode can have |
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260 | * several parents (no hard links for directories). |
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261 | * - The "children" field is an embedded xhtab containing pointers on all local children |
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262 | * dentries. This set of children is empty for a FILE inode. |
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263 | * Synchronisation: |
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264 | * - the main_lock (remote_rwlock) is used during the inode tree traversal, |
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265 | * or for inode modification (add/remove children in xhtab). |
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266 | * - the size_lock (remote_rwlock) is used during read/write accesses to the size |
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267 | * field in the mapper. |
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268 | * - access to the data stored in the associated mapper use the mapper remote_rwlock |
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269 | * protecting radix tree traversal and modifications. |
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270 | *****************************************************************************************/ |
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271 | |
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272 | /* this enum define the VFS inode attributes values */ |
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273 | |
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274 | typedef enum |
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275 | { |
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276 | INODE_ATTR_DIRTY = 0x01, /*! modified versus the value on device */ |
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277 | INODE_ATTR_INLOAD = 0x04, /*! loading from device in progress */ |
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278 | INODE_ATTR_NEW = 0x08, /*! not saved on device yet */ |
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279 | } |
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280 | vfs_inode_attr_t; |
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281 | |
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282 | typedef struct vfs_inode_s |
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283 | { |
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284 | struct vfs_ctx_s * ctx; /*! local pointer on FS context */ |
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285 | uint32_t inum; /*! inode identifier (unique in file system) */ |
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286 | uint32_t attr; /*! inode attributes (see above) */ |
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287 | vfs_file_type_t type; /*! inode type (see vfs_file_t) */ |
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288 | uint32_t size; /*! number of bytes */ |
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289 | uint32_t uid; /*! user owner identifier */ |
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290 | uint32_t gid; /*! group owner identifier */ |
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291 | uint32_t rights; /*! access rights */ |
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292 | xlist_entry_t parents; /*! root of list of parents dentries */ |
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293 | uint32_t links; /*! number of parent dentries (hard links) */ |
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294 | xhtab_t children; /*! embedded xhtab of children dentries */ |
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295 | remote_rwlock_t size_lock; /*! protect read/write to size */ |
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296 | remote_rwlock_t main_lock; /*! protect inode tree traversal and modifs */ |
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297 | struct mapper_s * mapper; /*! associated file (REG or DIR types only) */ |
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298 | struct remote_buf_s * pipe; /*! associated pipe (FIFO type only) */ |
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299 | void * extend; /*! fs_type_specific inode extension */ |
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300 | } |
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301 | vfs_inode_t; |
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302 | |
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303 | /* This define the masks for the inode <rights> field */ |
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304 | |
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305 | #define VFS_ISUID 0x0004000 |
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306 | #define VFS_ISGID 0x0002000 |
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307 | #define VFS_ISVTX 0x0001000 |
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308 | |
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309 | #define VFS_IRWXU 0x0000700 |
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310 | #define VFS_IRUSR 0x0000400 |
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311 | #define VFS_IWUSR 0x0000200 |
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312 | #define VFS_IXUSR 0x0000100 |
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313 | |
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314 | #define VFS_IRWXG 0x0000070 |
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315 | #define VFS_IRGRP 0x0000040 |
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316 | #define VFS_IWGRP 0x0000020 |
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317 | #define VFS_IXGRP 0x0000010 |
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318 | |
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319 | #define VFS_IRWXO 0x0000007 |
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320 | #define VFS_IROTH 0x0000004 |
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321 | #define VFS_IWOTH 0x0000002 |
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322 | #define VFS_IXOTH 0x0000001 |
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323 | |
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324 | /****************************************************************************************** |
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325 | * These low-level functions access / modify a VFS inode descriptor |
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326 | *****************************************************************************************/ |
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327 | |
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328 | /****************************************************************************************** |
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329 | * This function returns a printable string for the inode type. |
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330 | *****************************************************************************************/ |
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331 | const char * vfs_inode_type_str( vfs_file_type_t type ); |
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332 | |
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333 | /****************************************************************************************** |
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334 | * This function allocates memory in cluster identified by the <cxy> argument |
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335 | * for an inode descriptor and for the associated mapper, and partially initialise |
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336 | * this inode from arguments values. |
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337 | * It does NOT link it to the Inode Tree, as this is done by add_child_in_parent(). |
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338 | * It can be called by any thread running in any cluster. |
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339 | ****************************************************************************************** |
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340 | * @ cxy : [in] target cluster identifier |
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341 | * @ fs_type : [in] file system type. |
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342 | * @ attr : [in] inode attributes. |
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343 | * @ rights : [in] inode access rights. |
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344 | * @ uid : [in] user owner ID. |
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345 | * @ gid : [in] group owner ID. |
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346 | * @ inode_xp : [out] buffer for extended pointer on created inode. |
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347 | * @ return 0 if success / return -1 if error. |
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348 | *****************************************************************************************/ |
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349 | error_t vfs_inode_create( cxy_t cxy, |
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350 | vfs_fs_type_t fs_type, |
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351 | uint32_t attr, |
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352 | uint32_t rights, |
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353 | uid_t uid, |
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354 | gid_t gid, |
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355 | xptr_t * inode_xp ); |
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356 | |
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357 | /****************************************************************************************** |
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358 | * This function releases memory allocated to an inode descriptor, including |
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359 | * all memory allocated to the mapper (both mapper descriptor and radix tree). |
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360 | * The mapper should not contain any dirty page (should be synchronized before deletion). |
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361 | * It can be called by any thread running in any cluster. |
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362 | ****************************************************************************************** |
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363 | * @ inode_xp : extended pointer on inode descriptor. |
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364 | *****************************************************************************************/ |
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365 | void vfs_inode_destroy( xptr_t inode_xp ); |
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366 | |
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367 | /****************************************************************************************** |
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368 | * This function returns the <size> of a file/dir from a remote inode, |
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369 | * taking the remote_rwlock protecting <size> in READ_MODE. |
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370 | * It can be called by any thread running in any cluster. |
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371 | ***************************************************************************************** |
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372 | * @ inode_xp : extended pointer on the remote inode. |
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373 | * @ return the current size. |
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374 | *****************************************************************************************/ |
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375 | uint32_t vfs_inode_get_size( xptr_t inode_xp ); |
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376 | |
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377 | /****************************************************************************************** |
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378 | * This function updates the "size" field of a remote inode identified by <inode_xp>. |
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379 | * It takes the rwlock protecting the file size in WRITE_MODE, and set the "size" field |
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380 | * when the current size is smaller than the requested <size> argument. |
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381 | * It can be called by any thread running in any cluster. |
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382 | ***************************************************************************************** |
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383 | * @ inode_xp : extended pointer on the remote inode. |
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384 | * @ size : requested size value. |
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385 | *****************************************************************************************/ |
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386 | void vfs_inode_update_size( xptr_t inode_xp, |
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387 | uint32_t size ); |
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388 | |
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389 | /****************************************************************************************** |
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390 | * This function takes the main lock of a remote inode identified by the <inode_xp>. |
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391 | * This lock protect all inode fields, including the children dentries. |
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392 | * It can be called by any thread running in any cluster. |
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393 | ***************************************************************************************** |
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394 | * @ inode_xp : extended pointer on the remote inode. |
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395 | *****************************************************************************************/ |
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396 | void vfs_inode_lock( xptr_t inode_xp ); |
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397 | |
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398 | /****************************************************************************************** |
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399 | * This function releases the main lock of a remote inode identified by <inode_xp>. |
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400 | * This lock protect all inode fiels, including the children dentries. |
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401 | * It can be called by any thread running in any cluster. |
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402 | ***************************************************************************************** |
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403 | * @ inode_xp : extended pointer on the remote inode. |
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404 | *****************************************************************************************/ |
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405 | void vfs_inode_unlock( xptr_t inode_xp ); |
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406 | |
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407 | /****************************************************************************************** |
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408 | * This debug function copies the name of a remote inode identified by the <inode_xp> |
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409 | * argument to a local buffer identified by the <name> argument. |
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410 | * The local buffer size must be at least CONFIG_VFS_MAX_NAME_LENGTH. |
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411 | * It can be called by any thread running in any cluster. |
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412 | ****************************************************************************************** |
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413 | * @ inode_xp : extended pointer on the remote inode. |
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414 | * @ name : local buffer pointer. |
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415 | *****************************************************************************************/ |
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416 | void vfs_inode_get_name( xptr_t inode_xp, |
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417 | char * name ); |
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418 | |
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419 | /****************************************************************************************** |
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420 | * This function accesses successively all pages of a file identified by the <inode_xp>, |
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421 | * argument, to force misses, and load all pages into mapper. |
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422 | * The target inode can be a directory or a file, but this function is mainly used |
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423 | * to prefetch a complete directory to the mapper. |
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424 | * This function does NOT take any lock. |
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425 | * It can be called by any thread running in any cluster. |
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426 | ****************************************************************************************** |
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427 | * @ inode_xp : extended pointer on inode. |
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428 | * @ return 0 if success / return -1 if device access failure. |
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429 | *****************************************************************************************/ |
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430 | error_t vfs_inode_load_all_pages( xptr_t inode_xp ); |
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431 | |
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432 | /****************************************************************************************** |
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433 | * This debug function display the curren state of an inode descriptor. |
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434 | * It can be called by any thread running in any cluster. |
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435 | *****************************************************************************************/ |
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436 | void vfs_inode_display( xptr_t inode_xp ); |
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437 | |
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438 | |
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439 | |
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440 | |
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441 | |
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442 | |
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443 | /****************************************************************************************** |
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444 | * This structure defines a directory entry. |
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445 | * A dentry contains the name of a remote file/dir, an extended pointer on the |
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446 | * inode representing this file/dir, a local pointer on the inode representing |
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447 | * the parent directory. |
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448 | * A dentry can be member of the set of children of a given directory inode (xhtab). |
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449 | * A dentry can be member of the set of parents of a given inode (xlist). |
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450 | *****************************************************************************************/ |
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451 | |
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452 | typedef struct vfs_dentry_s |
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453 | { |
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454 | struct vfs_ctx_s * ctx; /*! local pointer on FS context */ |
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455 | char name[CONFIG_VFS_MAX_NAME_LENGTH]; |
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456 | uint32_t length; /*! name length (bytes) */ |
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457 | struct vfs_inode_s * parent; /*! local pointer on parent inode */ |
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458 | xptr_t child_xp; /*! extended pointer on child inode */ |
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459 | xlist_entry_t children; /*! member of set of children dentries */ |
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460 | xlist_entry_t parents; /*! member of set of parent dentries */ |
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461 | void * extend; /*! FS specific extension */ |
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462 | } |
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463 | vfs_dentry_t; |
---|
464 | |
---|
465 | /****************************************************************************************** |
---|
466 | * These low-level functions access / modify a VFS dentry descriptor |
---|
467 | *****************************************************************************************/ |
---|
468 | |
---|
469 | /****************************************************************************************** |
---|
470 | * This function allocates memory in cluster identified by the <cxy> argument |
---|
471 | * for a dentry descriptor, initialises it from arguments values, and returns |
---|
472 | * in <dentry_xp> the extended pointer on dentry. |
---|
473 | * It can be called by any thread running in any cluster. |
---|
474 | ****************************************************************************************** |
---|
475 | * @ cxy : [in] target cluster identifier |
---|
476 | * @ fs_type : [in] file system type. |
---|
477 | * @ name : [in] directory entry file/dir name. |
---|
478 | * @ dentry_xp : [out] buffer for extended pointer on created dentry. |
---|
479 | * @ return 0 if success / return ENOMEM or EINVAL if error. |
---|
480 | *****************************************************************************************/ |
---|
481 | error_t vfs_dentry_create( cxy_t cxy, |
---|
482 | vfs_fs_type_t fs_type, |
---|
483 | char * name, |
---|
484 | xptr_t * dentry_xp ); |
---|
485 | |
---|
486 | /****************************************************************************************** |
---|
487 | * This function removes the dentry from the parent inode xhtab, and releases the memory |
---|
488 | * allocated to the dentry descriptor. |
---|
489 | * It can be called by any thread running in any cluster. |
---|
490 | ****************************************************************************************** |
---|
491 | * @ dentry_xp : [in] extended pointer on dentry descriptor. |
---|
492 | *****************************************************************************************/ |
---|
493 | void vfs_dentry_destroy( xptr_t dentry_xp ); |
---|
494 | |
---|
495 | |
---|
496 | |
---|
497 | |
---|
498 | |
---|
499 | |
---|
500 | |
---|
501 | |
---|
502 | /****************************************************************************************** |
---|
503 | * These functions access / modify the distributed VFS Inode Tree |
---|
504 | *****************************************************************************************/ |
---|
505 | |
---|
506 | /****************************************************************************************** |
---|
507 | * This function returns in a kernel <buffer> allocated by the caller function, |
---|
508 | * the pathname of a file/dir identified by the <inode_xp> argument. |
---|
509 | * It traverse the Inode Tree from the target node to the root. |
---|
510 | * It can be called by any thread running in any cluster. |
---|
511 | * As this buffer if filled in "reverse order" (i.e. from the target inode to the root), |
---|
512 | * the pathname is stored in the higher part of the buffer. |
---|
513 | * A pointer on the first character of the pathname is returned in <first> buffer. |
---|
514 | * |
---|
515 | * WARNING : This function takes & releases the remote_rwlock protecting the Inode Tree. |
---|
516 | ****************************************************************************************** |
---|
517 | * @ inode_xp : [in] extended pointer on target inode descriptor. |
---|
518 | * @ buffer : [in] kernel buffer for pathname (allocated by caller). |
---|
519 | * @ first : [out] pointer on first character in buffer. |
---|
520 | * @ max_size : [in] max number of characters in buffer. |
---|
521 | * @ return 0 if success / return EINVAL if buffer too small. |
---|
522 | *****************************************************************************************/ |
---|
523 | error_t vfs_get_path( xptr_t inode_xp, |
---|
524 | char * buffer, |
---|
525 | char ** first, |
---|
526 | uint32_t max_size ); |
---|
527 | |
---|
528 | /****************************************************************************************** |
---|
529 | * This function traverses the the Inode Tree, from inode identified by the <root_xp> |
---|
530 | * argument, and returns in <inode_xp> the inode identified by the < pathname> argument. |
---|
531 | * It can be called by a thread running in any cluster. |
---|
532 | * It supports the following flags that define the lookup modes : |
---|
533 | * - VFS_LOOKUP_DIR : the searched inode must be a directory |
---|
534 | * - VFS_LOOKUP_OPEN : the search is for an open/opendir |
---|
535 | * - VFS_LOOKUP_PARENT : return the parent inode (not the inode itself) |
---|
536 | * - VFS_LOOKUP_CREATE : file/directory must be created if missing on IOC |
---|
537 | * - VFS_LOOKUP_EXCL : file cannot previously exist |
---|
538 | * As the inode Tree is a cache, the search policy is the following : |
---|
539 | * - If a given directory name in the path is not found in the inode tree, it try to load |
---|
540 | * the missing dentry/inode couple, from informations found in the parent directory. |
---|
541 | * - If this directory entry does not exist on IOC, it returns an error. |
---|
542 | * - If the file identified by the pathname does not exist on IOC but the |
---|
543 | * flag CREATE is set, the inode is created. It returns an error otherwise. |
---|
544 | * - If the the file identified by the pathname exist on device, but both flags EXCL |
---|
545 | * and CREATE are set, an error is returned. |
---|
546 | * - If the PARENT flag is set, it returns in <inode_xp> an extended pointer on the parent |
---|
547 | * inode, and copies in <last_name> buffer a string containing the last name in path. |
---|
548 | * |
---|
549 | * WARNING : The lock protecting the Inode Tree must be taken in read mode by the caller. |
---|
550 | * |
---|
551 | * TODO the access rights are not checked yet. |
---|
552 | ****************************************************************************************** |
---|
553 | * @ root_xp : [in] extended pointer on root inode (can be root of a subtree). |
---|
554 | * @ pathname : [in] path (can be relative or absolute). |
---|
555 | * @ lookup_mode : [in] flags defining the searching mode. |
---|
556 | * @ inode_xp : [out] buffer for extended pointer on searched inode. |
---|
557 | * @ last_name : [out] pointer on buffer for last name in path. |
---|
558 | * @ return 0 if success / ENOENT if inode not found , EACCES if permisson denied, |
---|
559 | *****************************************************************************************/ |
---|
560 | error_t vfs_lookup( xptr_t root_xp, |
---|
561 | char * pathname, |
---|
562 | uint32_t lookup_mode, |
---|
563 | xptr_t * inode_xp, |
---|
564 | char * last_name ); |
---|
565 | |
---|
566 | /****************************************************************************************** |
---|
567 | * This function creates a new couple dentry/inode, and insert it in the Inode-Tree. |
---|
568 | * Only the distributed Inode-Tree is modified: it does NOT modify the parent mapper, |
---|
569 | * and does NOT update the FS on IOC device. |
---|
570 | * It set the inode type to the default FILE_TYPE_REG value. |
---|
571 | * It can be executed by any thread running in any cluster (can be different from both |
---|
572 | * the child cluster and the parent cluster). |
---|
573 | * The new child inode and the parent inode can have different FS types. |
---|
574 | * |
---|
575 | * WARNING : The lock protecting the Inode Tree must be taken in write mode by the caller. |
---|
576 | ****************************************************************************************** |
---|
577 | * Implementation note |
---|
578 | * As there are cross-references between inode and dentry, this function implements |
---|
579 | * a five steps scenario : |
---|
580 | * 1) The dentry descriptor is created in the cluster containing the existing <parent_xp> |
---|
581 | * inode, and partially initialized, using the RPC_VFS_CREATE DENTRY if required. |
---|
582 | * 2) The inode and its associated mapper are created in cluster identified by <child_cxy>, |
---|
583 | * and partially initialised, using the RPC_VFS_CREATE_INODE if required. |
---|
584 | * 3) The pointers on dentry in parent inode are updated, using remote access. |
---|
585 | * 4) The pointers on dentry in child inode are updated, using remotes access. |
---|
586 | * 5) The pointers on parent and child inode in dentry are updated, using remotes access. |
---|
587 | ***************************************************************************************** |
---|
588 | * @ child_inode_cxy : [in] target cluster for child inode. |
---|
589 | * @ fs_type : [in] child inode FS type. |
---|
590 | * @ parent_inode_xp : [in] extended pointer on parent inode. |
---|
591 | * @ name : [in] new directory entry name. |
---|
592 | * @ dentry_xp : [out] buffer for extended pointer on dentry |
---|
593 | * @ child_inode_xp : [out] buffer for extended pointer on child inode. |
---|
594 | * @ return 0 if success / -1 if dentry or inode cannot be created. |
---|
595 | *****************************************************************************************/ |
---|
596 | error_t vfs_add_child_in_parent( cxy_t child_inode_cxy, |
---|
597 | vfs_fs_type_t fs_type, |
---|
598 | xptr_t parent_inode_xp, |
---|
599 | char * name, |
---|
600 | xptr_t * dentry_xp, |
---|
601 | xptr_t * child_inode_xp ); |
---|
602 | |
---|
603 | /****************************************************************************************** |
---|
604 | * This function removes a remote dentry and the associated inode from the Inode-Tree. |
---|
605 | * - It removes the dentry from the parent inode xhtab ("children" field), and from the |
---|
606 | * child inode xlist ("parents" field). |
---|
607 | * - It releases the memory allocated to the dentry descriptor. |
---|
608 | * - If the number of parents of the child inode is one, it also releases the memory |
---|
609 | * allocated to the child inode. |
---|
610 | * Only the Inode Tree is modified: it does NOT modify the parent mapper, |
---|
611 | * and does NOT update the FS on IOC device. |
---|
612 | * It can be executed by any thread running in any cluster (can be different from both |
---|
613 | * the inode cluster and the dentry cluster). |
---|
614 | * |
---|
615 | * WARNING : The lock protecting the Inode Tree must be taken in write mode by the caller. |
---|
616 | ****************************************************************************************** |
---|
617 | * @ dentry_xp : extended pointer on removed dentry. |
---|
618 | *****************************************************************************************/ |
---|
619 | void vfs_remove_child_from_parent( xptr_t dentry_xp ); |
---|
620 | |
---|
621 | /****************************************************************************************** |
---|
622 | * This function creates in the directory identified by the <child_inode_xp> argument, |
---|
623 | * the two special dentries <.> and <..>. The parent directory inode is defined |
---|
624 | * by the <parent_inode_xp> argument. The two dentries are introduced in the Inode Tree. |
---|
625 | * They are also introduced in the child directory mapper, and the IOC device is updated. |
---|
626 | * This function is called by all functions creating a brand new directory : vfs_mkdir(), |
---|
627 | * devfs_global_init(), and devfs_local_init(). |
---|
628 | * |
---|
629 | * WARNING : The lock protecting the Inode Tree must be taken in write mode by the caller. |
---|
630 | ****************************************************************************************** |
---|
631 | * @ child_xp : extended pointer on new directory inode. |
---|
632 | * @ parent_xp : extended pointer on parent directory inode. |
---|
633 | * @ return 0 if success / -1 if failure. |
---|
634 | *****************************************************************************************/ |
---|
635 | error_t vfs_add_special_dentries( xptr_t child_inode_xp, |
---|
636 | xptr_t parent_inode_xp ); |
---|
637 | |
---|
638 | /****************************************************************************************** |
---|
639 | * This recursive function diplays a complete inode/dentry sub-tree. |
---|
640 | * Any inode can be selected as the sub-tree root. |
---|
641 | * |
---|
642 | * TODO : this function should be protected against a concurrent Inode-Tree change. |
---|
643 | ****************************************************************************************** |
---|
644 | * @ inode_xp : extended pointer on sub-tree root inode. |
---|
645 | *****************************************************************************************/ |
---|
646 | void vfs_display( xptr_t inode_xp ); |
---|
647 | |
---|
648 | /****************************************************************************************** |
---|
649 | * This function mount a given file system type for a given process |
---|
650 | * TODO non implemented [AG]. |
---|
651 | *****************************************************************************************/ |
---|
652 | error_t vfs_mount_fs_root( struct device_s * device, |
---|
653 | uint32_t fs_type, |
---|
654 | struct process_s * process ); |
---|
655 | |
---|
656 | |
---|
657 | |
---|
658 | |
---|
659 | /****************************************************************************************** |
---|
660 | * These functions define the VFS "syscalls" API (user commands) |
---|
661 | *****************************************************************************************/ |
---|
662 | |
---|
663 | /****************************************************************************************** |
---|
664 | * This function moves <size> bytes between a remote file mapper, identified by the |
---|
665 | * <file_xp> argument, and a - possibly distributed - user space <buffer>, taken into |
---|
666 | * account the offset in <file_xp>. The transfer direction is defined by <to_buffer>. |
---|
667 | * It is called by the sys_read() and sys_write() functions. |
---|
668 | * - for a read, it checks the actual file size (registered in the inode descriptor), |
---|
669 | * against the (offset + count), and moves only the significant bytes. |
---|
670 | * - for a write, it updates the the file size in inode descriptor if required. |
---|
671 | * In case of write to the mapper, the "inode.size" field is updated as required. |
---|
672 | ****************************************************************************************** |
---|
673 | * @ to_buffer : mapper -> buffer if true / buffer -> mapper if false. |
---|
674 | * @ file_xp : extended pointer on the remote file descriptor. |
---|
675 | * @ buffer : user space pointer on buffer (can be physically distributed). |
---|
676 | * @ count : requested number of bytes from offset. |
---|
677 | * @ returns number of bytes actually moved if success / -1 if error. |
---|
678 | *****************************************************************************************/ |
---|
679 | uint32_t vfs_user_move( bool_t to_buffer, |
---|
680 | xptr_t file_xp, |
---|
681 | void * buffer, |
---|
682 | uint32_t count ); |
---|
683 | |
---|
684 | /****************************************************************************************** |
---|
685 | * This function moves <size> bytes between a remote file mapper, identified by the |
---|
686 | * <file_xp> argument, and a - possibly remote - kernel <buffer_xp>, taken into |
---|
687 | * account the offset in <file_xp>. The transfer direction is defined by <to_buffer>. |
---|
688 | * It is called by the elf_load_process() function. |
---|
689 | ****************************************************************************************** |
---|
690 | * @ to_buffer : mapper -> buffer if true / buffer -> mapper if false. |
---|
691 | * @ file_xp : extended pointer on the remote file descriptor. |
---|
692 | * @ buffer_xp : user space pointer on buffer (can be physically distributed). |
---|
693 | * @ size : requested number of bytes from offset. |
---|
694 | * @ returns 0 if success / -1 if error. |
---|
695 | *****************************************************************************************/ |
---|
696 | error_t vfs_kernel_move( bool_t to_buffer, |
---|
697 | xptr_t file_xp, |
---|
698 | xptr_t buffer_xp, |
---|
699 | uint32_t size ); |
---|
700 | |
---|
701 | /****************************************************************************************** |
---|
702 | * This function allocates a vfs_file_t structure in the cluster containing the inode |
---|
703 | * identified by the <root_xp> & <path> arguments. |
---|
704 | * It initializes it, register it in the reference process fd_array identified by the |
---|
705 | * <process_xp> argument, and returns both the extended pointer on the file descriptor, |
---|
706 | * and the allocated index in the <file_xp> and <file_id> buffers. |
---|
707 | * The pathname can be relative to current directory or absolute. |
---|
708 | * If the inode does not exist in the inode cache, it try to find the file on the IOC |
---|
709 | * device, and creates an inode on a pseudo randomly selected cluster if found. |
---|
710 | * It the requested file does not exist on device, it creates a new inode if the |
---|
711 | * O_CREAT flag is set, and return an error otherwise. |
---|
712 | * |
---|
713 | * WARNING : this function takes & releases the remote_rwlock protecting the Inode Tree. |
---|
714 | ****************************************************************************************** |
---|
715 | * @ root_xp : extended pointer on path root inode. |
---|
716 | * @ path : file pathname (absolute or relative to current directory). |
---|
717 | * @ process_xp : extended pointer on client reference process. |
---|
718 | * @ flags : defined in vfs_file_t structure. |
---|
719 | * @ mode : access rights (as defined by chmod). |
---|
720 | * @ file_xp : [out] buffer for extended pointer on created remote file descriptor. |
---|
721 | * @ file_id : [out] buffer for created file descriptor index in reference fd_array. |
---|
722 | * @ return 0 if success / return non-zero if error. |
---|
723 | *****************************************************************************************/ |
---|
724 | error_t vfs_open( xptr_t root_xp, |
---|
725 | char * path, |
---|
726 | xptr_t process_xp, |
---|
727 | uint32_t flags, |
---|
728 | uint32_t mode, |
---|
729 | xptr_t * file_xp, |
---|
730 | uint32_t * file_id ); |
---|
731 | |
---|
732 | /****************************************************************************************** |
---|
733 | * This function set a new value in the offset of the open file descriptor <file_xp>. |
---|
734 | * This value depends on the <whence> argument: |
---|
735 | * - if VFS_SEEK_SET, new value is <offset> |
---|
736 | * - if VFS_SEEK_CUR, new value is current_offset + <offset> |
---|
737 | * - if VFS_SEEK_END, new value is file_size + <offset> |
---|
738 | ****************************************************************************************** |
---|
739 | * @ file_xp : extended pointer on the remote open file descriptor. |
---|
740 | * @ offset : local pointer on source kernel buffer. |
---|
741 | * @ whence : VFS_SEEK_SET / VFS_SEEK_CUR / VFS_SEEK_END. |
---|
742 | * @ new_offset : [out] buffer for new offset value. |
---|
743 | * @ returns 0 if success / -1 if error. |
---|
744 | *****************************************************************************************/ |
---|
745 | error_t vfs_lseek( xptr_t file_xp, |
---|
746 | uint32_t offset, |
---|
747 | uint32_t whence, |
---|
748 | uint32_t * new_offset ); |
---|
749 | |
---|
750 | /****************************************************************************************** |
---|
751 | * This function close the - non-replicated - file descriptor identified by the <file_xp> |
---|
752 | * and <file_id> arguments. The <file_id> is required to reset the fd_array[] slot. |
---|
753 | * It can be called by a thread running in any cluster, and executes the following actions: |
---|
754 | * 1) It access the block device to updates all dirty pages from the mapper associated |
---|
755 | * to the file, and removes these pages from the dirty list, using an RPC if required. |
---|
756 | * 2) It updates the file size in all parent directory mapper(s), and update the modified |
---|
757 | * pages on the block device, using RPCs if required, only if the size is modified. |
---|
758 | * 3) All entries in the fd_array copies are directly reset by the calling thread, |
---|
759 | * using remote accesses. |
---|
760 | * 4) The memory allocated to file descriptor in cluster containing the inode is released, |
---|
761 | * using an RPC if cluster containing the file descriptor is remote. |
---|
762 | ****************************************************************************************** |
---|
763 | * @ file_xp : extended pointer on the file descriptor. |
---|
764 | * @ file_id : file descriptor index in fd_array[]. |
---|
765 | * @ returns 0 if success / -1 if error. |
---|
766 | *****************************************************************************************/ |
---|
767 | error_t vfs_close( xptr_t file_xp, |
---|
768 | uint32_t file_id ); |
---|
769 | |
---|
770 | /****************************************************************************************** |
---|
771 | * This function is called by the kernel to create in the file system a new directory |
---|
772 | * identified by the <root_xp> & <path> arguments, with the access permission defined |
---|
773 | * by the <rights> argument. All nodes in the path - but the last - must exist. |
---|
774 | * |
---|
775 | * WARNING : this function takes & releases the remote_rwlock protecting the Inode Tree. |
---|
776 | ****************************************************************************************** |
---|
777 | * @ root_xp : extended pointer on path root inode (any inode in Inode Tree). |
---|
778 | * @ path : pathname (absolute or relative to current directory). |
---|
779 | * @ rights : access rights. |
---|
780 | * @ returns 0 if success / -1 if error. |
---|
781 | *****************************************************************************************/ |
---|
782 | error_t vfs_mkdir( xptr_t root_xp, |
---|
783 | char * path, |
---|
784 | uint32_t rights ); |
---|
785 | |
---|
786 | /****************************************************************************************** |
---|
787 | * This function is called by the kernel to create in the file system a new directory |
---|
788 | * entry identified by the <new_root_xp> & <new_path> arguments, to be linked to an |
---|
789 | * existing inode, identified by the <old_root_xp> & <old_path> arguments. |
---|
790 | * If the link is successful, the link count of the target inode is incremented. |
---|
791 | * The <new_path> and <old_path> share equal access rights to the underlying inode. |
---|
792 | * Both the IOC device and the Inode Tree are modified. |
---|
793 | $ |
---|
794 | * TODO This function should handle any type of node, but the current implementation |
---|
795 | * handles only the FILE and DIR types. |
---|
796 | * |
---|
797 | * WARNING : this function takes & releases the remote_rwlock protecting the Inode Tree. |
---|
798 | ****************************************************************************************** |
---|
799 | * @ old_root_xp : extended pointer on old path root inode (any inode in Inode Tree). |
---|
800 | * @ old_path : old pathname (absolute or relative to current directory). |
---|
801 | * @ nld_root_xp : extended pointer on new path root inode (any inode in Inode Tree). |
---|
802 | * @ new_path : new pathname (absolute or relative to current directory). |
---|
803 | * @ returns 0 if success / -1 if error. |
---|
804 | *****************************************************************************************/ |
---|
805 | error_t vfs_link( xptr_t old_root_xp, |
---|
806 | char * old_path, |
---|
807 | xptr_t new_root_xp, |
---|
808 | char * new_path ); |
---|
809 | |
---|
810 | /****************************************************************************************** |
---|
811 | * This function is called by the kernel to remove from the file system a directory entry |
---|
812 | * identified by the <root_xp> & <path> arguments. |
---|
813 | * The link count of the target node is decremented. |
---|
814 | * If the removed link is the last, the target inode is deleted. |
---|
815 | * Both the IOC device and the Inode Tree are modified. |
---|
816 | * |
---|
817 | * TODO This function should handle any type of node, but the current implementation |
---|
818 | * handles only only the FILE and DIR types. |
---|
819 | * |
---|
820 | * WARNING : this function takes & releases the remote_rwlock protecting the Inode Tree. |
---|
821 | ****************************************************************************************** |
---|
822 | * @ root_xp : extended pointer on root inode (can be any inode in Inode Tree). |
---|
823 | * @ path : pathname (absolute or relative to current directory). |
---|
824 | * @ returns 0 if success / -1 if error. |
---|
825 | *****************************************************************************************/ |
---|
826 | error_t vfs_unlink( xptr_t root_xp, |
---|
827 | char * path ); |
---|
828 | |
---|
829 | /****************************************************************************************** |
---|
830 | * This function returns, in the structure pointed by the <st> pointer, various |
---|
831 | * informations on the file identified by the <root_inode_xp> and <patname> arguments. |
---|
832 | * |
---|
833 | * TODO : only partially implemented yet (only size and inum fields). |
---|
834 | * |
---|
835 | * WARNING : this function takes & releases the remote_rwlock protecting the Inode Tree. |
---|
836 | ****************************************************************************************** |
---|
837 | * @ root_xp : extended pointer on path root inode (any inode in Inode Tree) |
---|
838 | * @ pathname : pathname to target inode. |
---|
839 | * @ st : local pointer on the stat structure in kernel space. |
---|
840 | * @ returns 0 if success / -1 if error. |
---|
841 | *****************************************************************************************/ |
---|
842 | error_t vfs_stat( xptr_t root_xp, |
---|
843 | char * pathname, |
---|
844 | struct stat * st ); |
---|
845 | |
---|
846 | /****************************************************************************************** |
---|
847 | * This function creates a new inode/dentry couple for a new directory, and registers it |
---|
848 | * in the Inode Tree, as defined by the <root_xp>, <path>, and <mode> arguments. |
---|
849 | ****************************************************************************************** |
---|
850 | * @ root_xp : extended pointer on the path root directory. |
---|
851 | * @ path : pathname (absolute or relative to CWD). |
---|
852 | * @ mode : access rights (as defined by chmod) |
---|
853 | * @ returns 0 if success / -1 if error. |
---|
854 | *****************************************************************************************/ |
---|
855 | error_t vfs_mkdir( xptr_t root_xp, |
---|
856 | char * path, |
---|
857 | uint32_t mode ); |
---|
858 | |
---|
859 | /****************************************************************************************** |
---|
860 | * This function makes the directory identified by the <root_xp and <path> arguments |
---|
861 | * to become the working directory for the calling process. |
---|
862 | ****************************************************************************************** |
---|
863 | * @ root_xp : extended pointer on the path root directory. |
---|
864 | * @ path : pathname (absolute or relative to CWD). |
---|
865 | * return 0 if success / -1 if error. |
---|
866 | *****************************************************************************************/ |
---|
867 | error_t vfs_chdir( xptr_t root_xp, |
---|
868 | char * path ); |
---|
869 | |
---|
870 | /****************************************************************************************** |
---|
871 | * This function change the access rigths for the file/directory identified by the |
---|
872 | * <root_xp> and <path> arguments as defined by the <mode> argument value. |
---|
873 | * TODO not implemented yet |
---|
874 | ****************************************************************************************** |
---|
875 | * @ root_xp : extended pointer on the path root directory. |
---|
876 | * @ path : pathname (absolute or relative to CWD). |
---|
877 | * @ mode : access rights |
---|
878 | * return 0 if success / -1 if error. |
---|
879 | *****************************************************************************************/ |
---|
880 | error_t vfs_chmod( xptr_t root_xp, |
---|
881 | char * path, |
---|
882 | uint32_t mode ); |
---|
883 | |
---|
884 | /****************************************************************************************** |
---|
885 | * This function creates a new inode/dentry couple of FIFO type, and registers it |
---|
886 | * in the Inode Tree as specified by the <root_xp>, <path>, and <mode> arguments. |
---|
887 | ****************************************************************************************** |
---|
888 | * @ root_xp : [in] extended pointer on the root directory in path. |
---|
889 | * @ path : [in] pathname (absolute or relative to CWD). |
---|
890 | * @ mode : [in] access rights new value. |
---|
891 | *****************************************************************************************/ |
---|
892 | error_t vfs_mkfifo( xptr_t root_xp, |
---|
893 | char * path, |
---|
894 | uint32_t mode ); |
---|
895 | |
---|
896 | |
---|
897 | |
---|
898 | |
---|
899 | |
---|
900 | /****************************************************************************************** |
---|
901 | * These functions define the VFS "FS" API to access a specific File System |
---|
902 | *****************************************************************************************/ |
---|
903 | |
---|
904 | /****************************************************************************************** |
---|
905 | * This function introduces in a directory mapper identified by the <parent_inode_xp> |
---|
906 | * argument, a new entry identified by the <dentry_ptr> argument. |
---|
907 | * Depending on the file system type, it calls the proper, FS specific function. |
---|
908 | * All informations related to the new directory must be contained in the dentry |
---|
909 | * descriptor, or in the associated child inode descriptor. |
---|
910 | * The dentry descriptor "extend" field is updated as required by the specific FS. |
---|
911 | * Finally, it synchronously updates the parent directory on IOC device. |
---|
912 | * This function can be called by any thread running in any cluster. |
---|
913 | ****************************************************************************************** |
---|
914 | * @ parent : local pointer on parent (directory) inode. |
---|
915 | * @ dentry : local pointer on dentry containing name. |
---|
916 | * @ return 0 if success / return -1 if device access failure. |
---|
917 | *****************************************************************************************/ |
---|
918 | error_t vfs_fs_add_dentry( xptr_t parent_inode_xp, |
---|
919 | vfs_dentry_t * dentry_ptr ); |
---|
920 | |
---|
921 | /****************************************************************************************** |
---|
922 | * This function removes from a directory mapper identified by the <parent_inode_xp> |
---|
923 | * argument, an entry identified by the <dentry_ptr> argument. |
---|
924 | * Depending on the file system type, it calls the proper, FS specific function. |
---|
925 | * Finally, it synchronously updates the parent directory on IOC device. |
---|
926 | * This function can be called by any thread running in any cluster. |
---|
927 | ****************************************************************************************** |
---|
928 | * @ parent_inode_xp : extended pointer on parent (directory) inode. |
---|
929 | * @ dentry_ptr : local pointer on dentry containing name. |
---|
930 | * @ return 0 if success / return -1 if device access failure. |
---|
931 | *****************************************************************************************/ |
---|
932 | error_t vfs_fs_remove_dentry( xptr_t parent_inode_xp, |
---|
933 | vfs_dentry_t * dentry_ptr ); |
---|
934 | |
---|
935 | /****************************************************************************************** |
---|
936 | * This function scan a directory mapper, identified by the <parent_inode_xp> argument |
---|
937 | * to find a directory entry identified by the <dentry_ptr> argument, |
---|
938 | * and updates both the child inode descriptor, and the associated dentry descriptor: |
---|
939 | * - It set the "size", "type", and "extend" fields in inode descriptor. |
---|
940 | * - It set the "extend" field in dentry descriptor. |
---|
941 | * It is called by the vfs_lookup() function in case of miss, and does NOT take any lock. |
---|
942 | * Depending on the file system type, it calls the relevant, FS specific function. |
---|
943 | * This function can be called by any thread running in any cluster. |
---|
944 | ****************************************************************************************** |
---|
945 | * @ parent_inode_xp : extended pointer on parent inode (directory). |
---|
946 | * @ dentry_ptr : local pointer on new entry (in parent inode cluster). |
---|
947 | * @ return 0 if success / return -1 if dentry not found. |
---|
948 | *****************************************************************************************/ |
---|
949 | error_t vfs_fs_new_dentry_from_mapper( xptr_t parent_inode_xp, |
---|
950 | vfs_dentry_t * dentry_ptr ); |
---|
951 | |
---|
952 | /***************************************************************************************** |
---|
953 | * This function introduces a brand new dentry identified by the <dentry_ptr> argument |
---|
954 | * in the mapper of a directory identified by the <parent_inode_xp> argument. |
---|
955 | * It is called by the vfs_lookup() function, and does NOT take any lock. |
---|
956 | * The child inode descriptor, and the dentry descriptor must have been previously |
---|
957 | * allocated and introduced in the Inode Tree. The dentry descriptor contains the name. |
---|
958 | * Depending on the file system type, it calls the relevant, FS specific function. |
---|
959 | * This function can be called by any thread running in any cluster. |
---|
960 | ***************************************************************************************** |
---|
961 | * @ parent_inode_xp : [in] extended pointer on parent inode (directory). |
---|
962 | * @ dentry_ptr : [in] local pointer on dentry (in parent inode cluster). |
---|
963 | * @ return 0 if success / return -1 if failure. |
---|
964 | ****************************************************************************************/ |
---|
965 | error_t vfs_fs_new_dentry_to_mapper( xptr_t parent_inode_xp, |
---|
966 | vfs_dentry_t * dentry_ptr ); |
---|
967 | |
---|
968 | /****************************************************************************************** |
---|
969 | * This function updates the "size" field of a directory entry identified by the |
---|
970 | * <dentry_ptr> argument in a directory mapper identified by the <parent_inode_xp> |
---|
971 | * from the value contained in the inode descriptor. |
---|
972 | * The parent directory on device is synchronously updated. |
---|
973 | * It is called by the vfs_close() function. |
---|
974 | * Depending on the file system type, it calls the relevant, FS specific function. |
---|
975 | * This function can be called by any thread running in any cluster. |
---|
976 | ****************************************************************************************** |
---|
977 | * @ parent_inode_xp : local pointer on parent inode (directory). |
---|
978 | * @ dentry_ptr : local pointer on dentry (in parent directory cluster). |
---|
979 | * @ return 0 if success / return -1 if not found. |
---|
980 | *****************************************************************************************/ |
---|
981 | error_t vfs_fs_update_dentry( xptr_t parent_inode_xp, |
---|
982 | vfs_dentry_t * dentry_ptr ); |
---|
983 | |
---|
984 | /****************************************************************************************** |
---|
985 | * This function scan the mapper of an an existing parent inode directory, identified by |
---|
986 | * the <inode> argument and copy up to <max_dirent> valid dentries to a |
---|
987 | * local dirent array, defined by the <array> argument. The <min_dentry> argument defines |
---|
988 | * the index of the first dentry to copied to the target dirent array. |
---|
989 | * This function returns in the <entries> buffer the number of dentries actually written, |
---|
990 | * and signals in the <done> buffer when the last valid entry has been found. |
---|
991 | * If the <detailed> argument is true, a dentry/inode couple that does not exist in |
---|
992 | * the Inode Tree is dynamically created, and all dirent fiels are documented in the |
---|
993 | * dirent array. Otherwise, only the dentry name is documented. |
---|
994 | * This function does NOT take any lock. |
---|
995 | * Depending on the file system type, it calls the relevant, FS specific function. |
---|
996 | * |
---|
997 | * WARNING : this function must be called by a thread running in the cluster containing |
---|
998 | * the target directory inode. |
---|
999 | ****************************************************************************************** |
---|
1000 | * @ inode : [in] local pointer on directory inode. |
---|
1001 | * @ array : [in] local pointer on array of dirents. |
---|
1002 | * @ max_dirent : [in] max number of slots in dirent array. |
---|
1003 | * @ min_dentry : [in] index of first dentry to be copied into array. |
---|
1004 | * @ detailed : [in] dynamic inode creation if true. |
---|
1005 | * @ entries : [out] number of dentries actually copied into array. |
---|
1006 | * @ done : [out] Boolean true when last entry found. |
---|
1007 | * @ return 0 if success / return -1 if failure. |
---|
1008 | *****************************************************************************************/ |
---|
1009 | error_t vfs_fs_get_user_dir( vfs_inode_t * inode, |
---|
1010 | struct dirent * array, |
---|
1011 | uint32_t max_dirent, |
---|
1012 | uint32_t min_dentry, |
---|
1013 | bool_t detailed, |
---|
1014 | uint32_t * entries, |
---|
1015 | bool_t * done ); |
---|
1016 | |
---|
1017 | /***************************************************************************************** |
---|
1018 | * This function updates the FS on the IOC device for a given inode identified by |
---|
1019 | * the <inode> argument. It scan all pages registered in the associated mapper, |
---|
1020 | * and copies from mapper to device each page marked as dirty. |
---|
1021 | * WARNING : The target <inode> cannot be a directory, because all modifications in a |
---|
1022 | * directory are synchronously done on the IOC device by the two vfs_fs_add_dentry() |
---|
1023 | * and vfs_fs_remove_dentry() functions. |
---|
1024 | * Depending on the file system type, it calls the relevant, FS specific function. |
---|
1025 | * This function can be called by any thread running in any cluster. |
---|
1026 | ***************************************************************************************** |
---|
1027 | * @ inode_xp : remote pointer on inode. |
---|
1028 | * @ return 0 if success / return -1 if failure. |
---|
1029 | ****************************************************************************************/ |
---|
1030 | error_t vfs_fs_sync_inode( xptr_t inode_xp ); |
---|
1031 | |
---|
1032 | /***************************************************************************************** |
---|
1033 | * This function updates the FS defined by the <fs_type> argument on the IOC device |
---|
1034 | * for the FAT itself. It scan all clusters registered in the FAT mapper, and copies |
---|
1035 | * to device each page marked as dirty. |
---|
1036 | * Depending on the file system type, it calls the relevant, FS specific function. |
---|
1037 | * It can be called by a thread running in any cluster. |
---|
1038 | ***************************************************************************************** |
---|
1039 | * @ fs_type : specific file system type. |
---|
1040 | * @ return 0 if success / return EIO if failure during device access. |
---|
1041 | ****************************************************************************************/ |
---|
1042 | error_t vfs_fs_sync_fat( vfs_fs_type_t fs_type ); |
---|
1043 | |
---|
1044 | /****************************************************************************************** |
---|
1045 | * This function makes all I/O operations required to release all clusters allocated |
---|
1046 | * on IOC device to a given inode, identified by the <inode_xp> argument. |
---|
1047 | * Depending on the file system type, it calls the proper, FS specific function. |
---|
1048 | * It is called by the vfs_unlink() function. |
---|
1049 | * This function does NOT take any lock. |
---|
1050 | * Depending on the file system type, it calls the relevant, FS specific function. |
---|
1051 | * This function can be executed by any thread running in any cluster. |
---|
1052 | ****************************************************************************************** |
---|
1053 | * @ inode_xp : extended pointer on inode. |
---|
1054 | * @ return 0 if success / return -1 if device access failure. |
---|
1055 | *****************************************************************************************/ |
---|
1056 | error_t vfs_fs_release_inode( xptr_t inode_xp ); |
---|
1057 | |
---|
1058 | /****************************************************************************************** |
---|
1059 | * This function makes the I/O operation to move one page identified by the <page_xp> |
---|
1060 | * argument to/from the IOC device from/to the mapper, as defined by the <cmd_type>. |
---|
1061 | * It is used in case of MISS on the mapper (read), or when a dirty page in the mapper |
---|
1062 | * must be updated in the File System (write). |
---|
1063 | * The mapper pointer, and the page index in file are obtained from the page descriptor. |
---|
1064 | * This function does NOT take any lock. |
---|
1065 | * Depending on the file system type, it calls the proper, FS specific function. |
---|
1066 | * This function can be executed by any thread running in any cluster. |
---|
1067 | ****************************************************************************************** |
---|
1068 | * @ page_xp : extended pointer on page descriptor (for mapper and page_id). |
---|
1069 | * @ cmd_type : IOC_READ / IOC_WRITE / IOC_SYNC_READ / IOC_SYNC_WRITE |
---|
1070 | * @ returns 0 if success / return -1 if device access failure. |
---|
1071 | *****************************************************************************************/ |
---|
1072 | error_t vfs_fs_move_page( xptr_t page_xp, |
---|
1073 | ioc_cmd_type_t cmd_type ); |
---|
1074 | |
---|
1075 | |
---|
1076 | #endif /* _VFS_H_ */ |
---|