Rev 4420 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 4419 | trochtova | 1 | /* |
| 2 | * Copyright (c) 2008 Jakub Jermar |
||
| 3 | * All rights reserved. |
||
| 4 | * |
||
| 5 | * Redistribution and use in source and binary forms, with or without |
||
| 6 | * modification, are permitted provided that the following conditions |
||
| 7 | * are met: |
||
| 8 | * |
||
| 9 | * - Redistributions of source code must retain the above copyright |
||
| 10 | * notice, this list of conditions and the following disclaimer. |
||
| 11 | * - Redistributions in binary form must reproduce the above copyright |
||
| 12 | * notice, this list of conditions and the following disclaimer in the |
||
| 13 | * documentation and/or other materials provided with the distribution. |
||
| 14 | * - The name of the author may not be used to endorse or promote products |
||
| 15 | * derived from this software without specific prior written permission. |
||
| 16 | * |
||
| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
||
| 18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||
| 19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
||
| 20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
||
| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||
| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
||
| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
||
| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
||
| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
||
| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||
| 27 | */ |
||
| 28 | |||
| 29 | /** @addtogroup fs |
||
| 30 | * @{ |
||
| 31 | */ |
||
| 32 | |||
| 33 | #ifndef FAT_FAT_H_ |
||
| 34 | #define FAT_FAT_H_ |
||
| 35 | |||
| 36 | #include "fat_fat.h" |
||
| 37 | #include <ipc/ipc.h> |
||
| 38 | #include <libfs.h> |
||
| 39 | #include <atomic.h> |
||
| 40 | #include <sys/types.h> |
||
| 41 | #include <bool.h> |
||
| 42 | #include "../../vfs/vfs.h" |
||
| 43 | |||
| 44 | #ifndef dprintf |
||
| 45 | #define dprintf(...) printf(__VA_ARGS__) |
||
| 46 | #endif |
||
| 47 | |||
| 48 | #define min(a, b) ((a) < (b) ? (a) : (b)) |
||
| 49 | |||
| 50 | #define BS_BLOCK 0 |
||
| 51 | #define BS_SIZE 512 |
||
| 52 | |||
| 53 | typedef struct fat_bs { |
||
| 54 | uint8_t ji[3]; /**< Jump instruction. */ |
||
| 55 | uint8_t oem_name[8]; |
||
| 56 | /* BIOS Parameter Block */ |
||
| 57 | uint16_t bps; /**< Bytes per sector. */ |
||
| 58 | uint8_t spc; /**< Sectors per cluster. */ |
||
| 59 | uint16_t rscnt; /**< Reserved sector count. */ |
||
| 60 | uint8_t fatcnt; /**< Number of FATs. */ |
||
| 61 | uint16_t root_ent_max; /**< Maximum number of root directory |
||
| 62 | entries. */ |
||
| 63 | uint16_t totsec16; /**< Total sectors. 16-bit version. */ |
||
| 64 | uint8_t mdesc; /**< Media descriptor. */ |
||
| 65 | uint16_t sec_per_fat; /**< Sectors per FAT12/FAT16. */ |
||
| 66 | uint16_t sec_per_track; /**< Sectors per track. */ |
||
| 67 | uint16_t headcnt; /**< Number of heads. */ |
||
| 68 | uint32_t hidden_sec; /**< Hidden sectors. */ |
||
| 69 | uint32_t totsec32; /**< Total sectors. 32-bit version. */ |
||
| 70 | |||
| 71 | union { |
||
| 72 | struct { |
||
| 73 | /* FAT12/FAT16 only: Extended BIOS Parameter Block */ |
||
| 74 | /** Physical drive number. */ |
||
| 75 | uint8_t pdn; |
||
| 76 | uint8_t reserved; |
||
| 77 | /** Extended boot signature. */ |
||
| 78 | uint8_t ebs; |
||
| 79 | /** Serial number. */ |
||
| 80 | uint32_t id; |
||
| 81 | /** Volume label. */ |
||
| 82 | uint8_t label[11]; |
||
| 83 | /** FAT type. */ |
||
| 84 | uint8_t type[8]; |
||
| 85 | /** Boot code. */ |
||
| 86 | uint8_t boot_code[448]; |
||
| 87 | /** Boot sector signature. */ |
||
| 88 | uint16_t signature; |
||
| 89 | } __attribute__ ((packed)); |
||
| 90 | struct { |
||
| 91 | /* FAT32 only */ |
||
| 92 | /** Sectors per FAT. */ |
||
| 93 | uint32_t sectors_per_fat; |
||
| 94 | /** FAT flags. */ |
||
| 95 | uint16_t flags; |
||
| 96 | /** Version. */ |
||
| 97 | uint16_t version; |
||
| 98 | /** Cluster number of root directory. */ |
||
| 99 | uint32_t root_cluster; |
||
| 100 | /** Sector number of file system information sector. */ |
||
| 101 | uint16_t fsinfo_sec; |
||
| 102 | /** Sector number of boot sector copy. */ |
||
| 103 | uint16_t bscopy_sec; |
||
| 104 | uint8_t reserved1[12]; |
||
| 105 | /** Physical drive number. */ |
||
| 106 | uint8_t pdn; |
||
| 107 | uint8_t reserved2; |
||
| 108 | /** Extended boot signature. */ |
||
| 109 | uint8_t ebs; |
||
| 110 | /** Serial number. */ |
||
| 111 | uint32_t id; |
||
| 112 | /** Volume label. */ |
||
| 113 | uint8_t label[11]; |
||
| 114 | /** FAT type. */ |
||
| 115 | uint8_t type[8]; |
||
| 116 | /** Boot code. */ |
||
| 117 | uint8_t boot_code[420]; |
||
| 118 | /** Signature. */ |
||
| 119 | uint16_t signature; |
||
| 120 | } __attribute__ ((packed)); |
||
| 121 | }; |
||
| 122 | } __attribute__ ((packed)) fat_bs_t; |
||
| 123 | |||
| 124 | typedef enum { |
||
| 125 | FAT_INVALID, |
||
| 126 | FAT_DIRECTORY, |
||
| 127 | FAT_FILE |
||
| 128 | } fat_node_type_t; |
||
| 129 | |||
| 130 | struct fat_node; |
||
| 131 | |||
| 132 | /** FAT index structure. |
||
| 133 | * |
||
| 134 | * This structure exists to help us to overcome certain limitations of the FAT |
||
| 135 | * file system design. The problem with FAT is that it is hard to find |
||
| 136 | * an entity which could represent a VFS index. There are two candidates: |
||
| 137 | * |
||
| 138 | * a) number of the node's first cluster |
||
| 139 | * b) the pair of the parent directory's first cluster and the dentry index |
||
| 140 | * within the parent directory |
||
| 141 | * |
||
| 142 | * We need VFS indices to be: |
||
| 143 | * A) unique |
||
| 144 | * B) stable in time, at least until the next mount |
||
| 145 | * |
||
| 146 | * Unfortunately a) does not meet the A) criterion because zero-length files |
||
| 147 | * will have the first cluster field cleared. And b) does not meet the B) |
||
| 148 | * criterion because unlink() and rename() will both free up the original |
||
| 149 | * dentry, which contains all the essential info about the file. |
||
| 150 | * |
||
| 151 | * Therefore, a completely opaque indices are used and the FAT server maintains |
||
| 152 | * a mapping between them and otherwise nice b) variant. On rename(), the VFS |
||
| 153 | * index stays unaltered, while the internal FAT "physical tree address" |
||
| 154 | * changes. The unlink case is also handled this way thanks to an in-core node |
||
| 155 | * pointer embedded in the index structure. |
||
| 156 | */ |
||
| 157 | typedef struct { |
||
| 158 | /** Used indices (position) hash table link. */ |
||
| 159 | link_t uph_link; |
||
| 160 | /** Used indices (index) hash table link. */ |
||
| 161 | link_t uih_link; |
||
| 162 | |||
| 163 | futex_t lock; |
||
| 164 | dev_handle_t dev_handle; |
||
| 165 | fs_index_t index; |
||
| 166 | /** |
||
| 167 | * Parent node's first cluster. |
||
| 168 | * Zero is used if this node is not linked, in which case nodep must |
||
| 169 | * contain a pointer to the in-core node structure. |
||
| 170 | * One is used when the parent is the root directory. |
||
| 171 | */ |
||
| 172 | fat_cluster_t pfc; |
||
| 173 | /** Directory entry index within the parent node. */ |
||
| 174 | unsigned pdi; |
||
| 175 | /** Pointer to in-core node instance. */ |
||
| 176 | struct fat_node *nodep; |
||
| 177 | } fat_idx_t; |
||
| 178 | |||
| 179 | /** FAT in-core node. */ |
||
| 180 | typedef struct fat_node { |
||
| 4420 | trochtova | 181 | /** Back pointer to the FS node. */ |
| 182 | fs_node_t *bp; |
||
| 183 | |||
| 4419 | trochtova | 184 | futex_t lock; |
| 185 | fat_node_type_t type; |
||
| 186 | fat_idx_t *idx; |
||
| 187 | /** |
||
| 188 | * Node's first cluster. |
||
| 189 | * Zero is used for zero-length nodes. |
||
| 190 | * One is used to mark root directory. |
||
| 191 | */ |
||
| 192 | fat_cluster_t firstc; |
||
| 193 | /** FAT in-core node free list link. */ |
||
| 194 | link_t ffn_link; |
||
| 195 | size_t size; |
||
| 196 | unsigned lnkcnt; |
||
| 197 | unsigned refcnt; |
||
| 198 | bool dirty; |
||
| 199 | } fat_node_t; |
||
| 200 | |||
| 201 | extern fs_reg_t fat_reg; |
||
| 202 | |||
| 203 | extern void fat_mounted(ipc_callid_t, ipc_call_t *); |
||
| 204 | extern void fat_mount(ipc_callid_t, ipc_call_t *); |
||
| 205 | extern void fat_lookup(ipc_callid_t, ipc_call_t *); |
||
| 206 | extern void fat_read(ipc_callid_t, ipc_call_t *); |
||
| 207 | extern void fat_write(ipc_callid_t, ipc_call_t *); |
||
| 208 | extern void fat_truncate(ipc_callid_t, ipc_call_t *); |
||
| 4537 | trochtova | 209 | extern void fat_close(ipc_callid_t, ipc_call_t *); |
| 4419 | trochtova | 210 | extern void fat_destroy(ipc_callid_t, ipc_call_t *); |
| 4537 | trochtova | 211 | extern void fat_open_node(ipc_callid_t, ipc_call_t *); |
| 212 | extern void fat_device(ipc_callid_t, ipc_call_t *); |
||
| 213 | extern void fat_sync(ipc_callid_t, ipc_call_t *); |
||
| 4419 | trochtova | 214 | |
| 215 | extern fat_idx_t *fat_idx_get_new(dev_handle_t); |
||
| 216 | extern fat_idx_t *fat_idx_get_by_pos(dev_handle_t, fat_cluster_t, unsigned); |
||
| 217 | extern fat_idx_t *fat_idx_get_by_index(dev_handle_t, fs_index_t); |
||
| 218 | extern void fat_idx_destroy(fat_idx_t *); |
||
| 219 | extern void fat_idx_hashin(fat_idx_t *); |
||
| 220 | extern void fat_idx_hashout(fat_idx_t *); |
||
| 221 | |||
| 222 | extern int fat_idx_init(void); |
||
| 223 | extern void fat_idx_fini(void); |
||
| 224 | extern int fat_idx_init_by_dev_handle(dev_handle_t); |
||
| 225 | extern void fat_idx_fini_by_dev_handle(dev_handle_t); |
||
| 226 | |||
| 227 | #endif |
||
| 228 | |||
| 229 | /** |
||
| 230 | * @} |
||
| 231 | */ |