| 0,0 → 1,227 |
|---|
| /* |
| * Copyright (c) 2008 Jakub Jermar |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * - Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * - Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * - The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| /** @addtogroup fs |
| * @{ |
| */ |
| |
| #ifndef FAT_FAT_H_ |
| #define FAT_FAT_H_ |
| |
| #include <ipc/ipc.h> |
| #include <libfs.h> |
| #include <atomic.h> |
| #include <sys/types.h> |
| #include <bool.h> |
| #include "../../vfs/vfs.h" |
| |
| #define dprintf(...) printf(__VA_ARGS__) |
| |
| typedef struct { |
| uint8_t ji[3]; /**< Jump instruction. */ |
| uint8_t oem_name[8]; |
| /* BIOS Parameter Block */ |
| uint16_t bps; /**< Bytes per sector. */ |
| uint8_t spc; /**< Sectors per cluster. */ |
| uint16_t rscnt; /**< Reserved sector count. */ |
| uint8_t fatcnt; /**< Number of FATs. */ |
| uint16_t root_ent_max; /**< Maximum number of root directory |
| entries. */ |
| uint16_t totsec16; /**< Total sectors. 16-bit version. */ |
| uint8_t mdesc; /**< Media descriptor. */ |
| uint16_t sec_per_fat; /**< Sectors per FAT12/FAT16. */ |
| uint16_t sec_per_track; /**< Sectors per track. */ |
| uint16_t headcnt; /**< Number of heads. */ |
| uint32_t hidden_sec; /**< Hidden sectors. */ |
| uint32_t totsec32; /**< Total sectors. 32-bit version. */ |
| |
| union { |
| struct { |
| /* FAT12/FAT16 only: Extended BIOS Parameter Block */ |
| /** Physical drive number. */ |
| uint8_t pdn; |
| uint8_t reserved; |
| /** Extended boot signature. */ |
| uint8_t ebs; |
| /** Serial number. */ |
| uint32_t id; |
| /** Volume label. */ |
| uint8_t label[11]; |
| /** FAT type. */ |
| uint8_t type[8]; |
| /** Boot code. */ |
| uint8_t boot_code[448]; |
| /** Boot sector signature. */ |
| uint16_t signature; |
| } __attribute__ ((packed)); |
| struct { |
| /* FAT32 only */ |
| /** Sectors per FAT. */ |
| uint32_t sectors_per_fat; |
| /** FAT flags. */ |
| uint16_t flags; |
| /** Version. */ |
| uint16_t version; |
| /** Cluster number of root directory. */ |
| uint32_t root_cluster; |
| /** Sector number of file system information sector. */ |
| uint16_t fsinfo_sec; |
| /** Sector number of boot sector copy. */ |
| uint16_t bscopy_sec; |
| uint8_t reserved1[12]; |
| /** Physical drive number. */ |
| uint8_t pdn; |
| uint8_t reserved2; |
| /** Extended boot signature. */ |
| uint8_t ebs; |
| /** Serial number. */ |
| uint32_t id; |
| /** Volume label. */ |
| uint8_t label[11]; |
| /** FAT type. */ |
| uint8_t type[8]; |
| /** Boot code. */ |
| uint8_t boot_code[420]; |
| /** Signature. */ |
| uint16_t signature; |
| } __attribute__ ((packed)); |
| }; |
| } __attribute__ ((packed)) fat_bs_t; |
| |
| #define FAT_ATTR_RDONLY (1 << 0) |
| #define FAT_ATTR_VOLLABEL (1 << 3) |
| #define FAT_ATTR_SUBDIR (1 << 4) |
| |
| typedef struct { |
| uint8_t name[8]; |
| uint8_t ext[3]; |
| uint8_t attr; |
| uint8_t reserved; |
| uint8_t ctime_fine; |
| uint16_t ctime; |
| uint16_t cdate; |
| uint16_t adate; |
| union { |
| uint16_t eaidx; /* FAT12/FAT16 */ |
| uint16_t firstc_hi; /* FAT32 */ |
| }; |
| uint16_t mtime; |
| uint16_t mdate; |
| union { |
| uint16_t firstc; /* FAT12/FAT16 */ |
| uint16_t firstc_lo; /* FAT32 */ |
| }; |
| uint32_t size; |
| } __attribute__ ((packed)) fat_dentry_t; |
| |
| typedef uint16_t fat_cluster_t; |
| |
| typedef enum { |
| FAT_INVALID, |
| FAT_DIRECTORY, |
| FAT_FILE |
| } fat_node_type_t; |
| |
| struct fat_node; |
| |
| /** FAT index structure. |
| * |
| * This structure exists to help us to overcome certain limitations of the FAT |
| * file system design. The problem with FAT is that it is hard to find |
| * an entity which could represent a VFS index. There are two candidates: |
| * |
| * a) number of the node's first cluster |
| * b) the pair of the parent directory's first cluster and the dentry index |
| * within the parent directory |
| * |
| * We need VFS indices to be: |
| * A) unique |
| * B) stable in time, at least until the next mount |
| * |
| * Unfortunately a) does not meet the A) criterion because zero-length files |
| * will have the first cluster field cleared. And b) does not meet the B) |
| * criterion because unlink() and rename() will both free up the original |
| * dentry, which contains all the essential info about the file. |
| * |
| * Therefore, a completely opaque indices are used and the FAT server maintains |
| * a mapping between them and otherwise nice b) variant. On rename(), the VFS |
| * index stays unaltered, while the internal FAT "physical tree address" |
| * changes. The unlink case is also handled this way thanks to an in-core node |
| * pointer embedded in the index structure. |
| */ |
| typedef struct { |
| /** Used indices (position) hash table link. */ |
| link_t uph_link; |
| /** Used indices (index) hash table link. */ |
| link_t uih_link; |
| |
| dev_handle_t dev_handle; |
| fs_index_t index; |
| /** |
| * Parent node's first cluster. |
| * Zero is used if this node is not linked, in which case nodep must |
| * contain a pointer to the in-core node structure. |
| * One is used when the parent is the root directory. |
| */ |
| fat_cluster_t pfc; |
| /** Directory entry index within the parent node. */ |
| unsigned pdi; |
| /** Pointer to in-core node instance. */ |
| struct fat_node *nodep; |
| } fat_idx_t; |
| |
| /** FAT in-core node. */ |
| typedef struct fat_node { |
| fat_node_type_t type; |
| fat_idx_t *idx; |
| /** |
| * Node's first cluster. |
| * Zero is used for zero-length nodes. |
| * One is used to mark root directory. |
| */ |
| fat_cluster_t firstc; |
| /** FAT in-core node free list link. */ |
| link_t ffn_link; |
| size_t size; |
| unsigned lnkcnt; |
| unsigned refcnt; |
| bool dirty; |
| } fat_node_t; |
| |
| extern fs_reg_t fat_reg; |
| |
| extern void fat_lookup(ipc_callid_t, ipc_call_t *); |
| |
| extern fat_idx_t *fat_idx_get_by_pos(dev_handle_t, fat_cluster_t, unsigned); |
| extern fat_idx_t *fat_idx_get_by_index(dev_handle_t, fs_index_t); |
| |
| #endif |
| |
| /** |
| * @} |
| */ |