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Diffstat (limited to 'nuttx/fs/fat/fs_writefat.c')
-rw-r--r-- | nuttx/fs/fat/fs_writefat.c | 544 |
1 files changed, 544 insertions, 0 deletions
diff --git a/nuttx/fs/fat/fs_writefat.c b/nuttx/fs/fat/fs_writefat.c new file mode 100644 index 000000000..02d55d625 --- /dev/null +++ b/nuttx/fs/fat/fs_writefat.c @@ -0,0 +1,544 @@ +/**************************************************************************** + * fs/fat/fs_writefat.c + * + * Copyright (C) 2008-2009, 2011 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <spudmonkey@racsa.co.cr> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * 3. Neither the name NuttX nor the names of its contributors may be + * used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "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 + * COPYRIGHT OWNER OR CONTRIBUTORS 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. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> + +#include <sys/types.h> +#include <stdint.h> +#include <string.h> +#include <errno.h> + +#include <nuttx/fs/fs.h> +#include <nuttx/fs/fat.h> +#include <nuttx/fs/mkfatfs.h> + +#include "fs_internal.h" +#include "fs_fat32.h" +#include "fs_mkfatfs.h" + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: mkfatfs_initmbr + * + * Description: + * Initialize the sector image of a masterbood record + * + * Input: + * fmt - User specified format parameters + * var - Other format parameters that are not user specifiable + * + * Return: + * None; caller is responsible for providing valid parameters. + * + ****************************************************************************/ +static inline void mkfatfs_initmbr(FAR struct fat_format_s *fmt, + FAR struct fat_var_s *var) +{ + memset(var->fv_sect, 0, var->fv_sectorsize); + + /* 3@0: Jump instruction to boot code */ + + memcpy(&var->fv_sect[BS_JUMP], var->fv_jump, 3); + + /* 8@3: Usually "MSWIN4.1" */ + + strcpy((char*)&var->fv_sect[BS_OEMNAME], "NUTTX "); + + /* 2@11: Bytes per sector: 512, 1024, 2048, 4096 */ + + MBR_PUTBYTESPERSEC(var->fv_sect, var->fv_sectorsize); + + /* 1@13: Sectors per allocation unit: 2**n, n=0..7 */ + + MBR_PUTSECPERCLUS(var->fv_sect, (1 << fmt->ff_clustshift)); + + /* 2@14: Reserved sector count: Usually 32 */ + + MBR_PUTRESVDSECCOUNT(var->fv_sect, fmt->ff_rsvdseccount); + + /* 1@16: Number of FAT data structures: always 2 */ + + MBR_PUTNUMFATS(var->fv_sect, fmt->ff_nfats); + + /* 2@17: FAT12/16: Must be 0 for FAT32 */ + + MBR_PUTROOTENTCNT(var->fv_sect, fmt->ff_rootdirentries); + + /* 2@19: FAT12/16: Must be 0, see BS_TOTSEC32. + * Handled with 4@32: Total count of sectors on the volume */ + + if (fmt->ff_nsectors >= 65536) + { + MBR_PUTTOTSEC32(var->fv_sect, fmt->ff_nsectors); + } + else + { + MBR_PUTTOTSEC16(var->fv_sect, (uint16_t)fmt->ff_nsectors); + } + + /* 1@21: Media code: f0, f8, f9-fa, fc-ff */ + + MBR_PUTMEDIA(var->fv_sect, FAT_DEFAULT_MEDIA_TYPE); /* Only "hard drive" supported */ + + /* 2@22: FAT12/16: Must be 0, see BS32_FATSZ32 -- handled in FAT specific logic */ + + /* 2@24: Sectors per track geometry value and 2@26: Number of heads geometry value */ + + MBR_PUTSECPERTRK(var->fv_sect, FAT_DEFAULT_SECPERTRK); + MBR_PUTNUMHEADS(var->fv_sect, FAT_DEFAULT_NUMHEADS); + + /* 4@28: Count of hidden sectors preceding FAT */ + + MBR_PUTHIDSEC(var->fv_sect, fmt->ff_hidsec); + + /* 4@32: Total count of sectors on the volume -- handled above */ + + /* Most of the rest of the sector depends on the FAT size */ + + if (fmt->ff_fattype != 32) + { + /* 2@22: FAT12/16: Must be 0, see BS32_FATSZ32 */ + + MBR_PUTFATSZ16(var->fv_sect, (uint16_t)var->fv_nfatsects); + + /* The following fields are only valid for FAT12/16 */ + /* 1@36: Drive number for MSDOS bootstrap -- left zero */ + /* 1@37: Reserved (zero) */ + /* 1@38: Extended boot signature: 0x29 if following valid */ + + MBR_PUTBOOTSIG16(var->fv_sect, EXTBOOT_SIGNATURE); + + /* 4@39: Volume serial number */ + + MBR_PUTVOLID16(var->fv_sect, fmt->ff_volumeid); + + /* 11@43: Volume label */ + + memcpy(&var->fv_sect[BS16_VOLLAB], fmt->ff_volumelabel, 11); + + /* 8@54: "FAT12 ", "FAT16 ", or "FAT " */ + + if (fmt->ff_fattype == 12) + { + memcpy(&var->fv_sect[BS16_FILESYSTYPE], "FAT12 ", 8); + } + else /* if (fmt->ff_fattype == 16) */ + { + memcpy(&var->fv_sect[BS16_FILESYSTYPE], "FAT16 ", 8); + } + + /* Boot code may be placed in the remainder of the sector */ + + memcpy(&var->fv_sect[BS16_BOOTCODE], var->fv_bootcode, var->fv_bootcodesize); + } + else + { + /* The following fields are only valid for FAT32 */ + /* 4@36: Count of sectors occupied by one FAT */ + + MBR_PUTFATSZ32(var->fv_sect, var->fv_nfatsects); + + /* 2@40: 0-3:Active FAT, 7=0 both FATS, 7=1 one FAT -- left zero*/ + /* 2@42: MSB:Major LSB:Minor revision number (0.0) -- left zero */ + /* 4@44: Cluster no. of 1st cluster of root dir */ + + MBR_PUTROOTCLUS(var->fv_sect, FAT32_DEFAULT_ROOT_CLUSTER); + + /* 2@48: Sector number of fsinfo structure. Usually 1. */ + + MBR_PUTFSINFO(var->fv_sect, FAT_DEFAULT_FSINFO_SECTOR); + + /* 2@50: Sector number of boot record. Usually 6 */ + + MBR_PUTBKBOOTSEC(var->fv_sect, fmt->ff_backupboot); + + /* 12@52: Reserved (zero) */ + /* 1@64: Drive number for MSDOS bootstrap -- left zero */ + /* 1@65: Reserved (zero) */ + /* 1@66: Extended boot signature: 0x29 if following valid */ + + MBR_PUTBOOTSIG32(var->fv_sect, EXTBOOT_SIGNATURE); + + /* 4@67: Volume serial number */ + + MBR_PUTVOLID32(var->fv_sect, fmt->ff_volumeid); + + /* 11@71: Volume label */ + + memcpy(&var->fv_sect[BS32_VOLLAB], fmt->ff_volumelabel, 11); + + /* 8@82: "FAT12 ", "FAT16 ", or "FAT " */ + + memcpy(&var->fv_sect[BS32_FILESYSTYPE], "FAT32 ", 8); + + /* Boot code may be placed in the remainder of the sector */ + + memcpy(&var->fv_sect[BS16_BOOTCODE], var->fv_bootcode, var->fv_bootcodesize); + } + + /* The magic bytes at the end of the MBR are common to FAT12/16/32 */ + /* 2@510: Valid MBRs have 0x55aa here */ + + MBR_PUTSIGNATURE(var->fv_sect, BOOT_SIGNATURE16); +} + +/**************************************************************************** + * Name: mkfatfs_initfsinfo + * + * Description: + * Initialize the FAT32 FSINFO sector image + * + * Input: + * fmt - User specified format parameters + * var - Other format parameters that are not user specifiable + * + * Return: + * None; caller is responsible for providing valid parameters. + * + ****************************************************************************/ +static inline void mkfatfs_initfsinfo(FAR struct fat_format_s *fmt, + FAR struct fat_var_s *var) +{ + memset(var->fv_sect, 0, var->fv_sectorsize); + + /* 4@0: 0x41615252 = "RRaA" */ + + FSI_PUTLEADSIG(var->fv_sect, 0x41615252); + + /* 480@4: Reserved (zero) */ + /* 4@484: 0x61417272 = "rrAa" */ + + FSI_PUTSTRUCTSIG(var->fv_sect, 0x61417272); + + /* 4@488: Last free cluster count on volume */ + + FSI_PUTFREECOUNT(var->fv_sect, var->fv_nclusters - 1); + + /* 4@492: Cluster number of 1st free cluster */ + + FSI_PUTNXTFREE(var->fv_sect, FAT32_DEFAULT_ROOT_CLUSTER); + + /* 12@496: Reserved (zero) */ + /* 4@508: 0xaa550000 */ + + FSI_PUTTRAILSIG(var->fv_sect, BOOT_SIGNATURE32); +} + +/**************************************************************************** + * Name: mkfatfs_initrootdir + * + * Description: + * Initialize one root directory sector image + * + * Input: + * fmt - User specified format parameters + * var - Other format parameters that are not user specifiable + * sectno - On FAT32, the root directory is a cluster chain. + * This value indicates which sector of the cluster should be produced. + * + * Return: + * None; caller is responsible for providing valid parameters. + * + ****************************************************************************/ +static inline void mkfatfs_initrootdir(FAR struct fat_format_s *fmt, + FAR struct fat_var_s *var, int sectno) +{ + memset(var->fv_sect, 0, var->fv_sectorsize); + if (sectno == 0) + { + /* It is only necessary to set data in the first sector of the directory */ + + if (memcmp(fmt->ff_volumelabel, " ", 11)) + { + memcpy(&var->fv_sect[DIR_NAME], fmt->ff_volumelabel, 11); + } + + DIR_PUTATTRIBUTES(var->fv_sect, FATATTR_VOLUMEID); + DIR_PUTCRTIME(var->fv_sect, var->fv_createtime & 0xffff); + DIR_PUTWRTTIME(var->fv_sect, var->fv_createtime & 0xffff); + DIR_PUTCRDATE(var->fv_sect, var->fv_createtime >> 16); + DIR_PUTWRTDATE(var->fv_sect, var->fv_createtime >> 16); + } +} + +/**************************************************************************** + * Name: mkfatfs_writembr + * + * Description: + * Write the master boot record and, for FAT32, the backup boot record and + * the fsinfo sector. + * + * Input: + * fmt - User specified format parameters + * var - Other format parameters that are not user specifiable + * + * Return: + * Zero on success; negated errno on failure + * + ****************************************************************************/ + +static inline int mkfatfs_writembr(FAR struct fat_format_s *fmt, + FAR struct fat_var_s *var) +{ + int sectno; + int ret; + + /* Create an image of the configured master boot record */ + + mkfatfs_initmbr(fmt, var); + + /* Write the master boot record as sector zero */ + + ret = DEV_WRITE(var->fv_sect, 0, 1); + + /* Write all of the reserved sectors */ + + memset(var->fv_sect, 0, var->fv_sectorsize); + for (sectno = 1; sectno < fmt->ff_rsvdseccount && ret >= 0; sectno++) + { + ret = DEV_WRITE(var->fv_sect, sectno, 1); + } + + /* Write FAT32-specific sectors */ + + if (ret >= 0 && fmt->ff_fattype == 32) + { + /* Write the backup master boot record */ + + if (fmt->ff_backupboot != 0) + { + /* Create another copy of the configured master boot record */ + + mkfatfs_initmbr(fmt, var); + + /* Write it to the backup location */ + + ret = DEV_WRITE(var->fv_sect, fmt->ff_backupboot, 1); + } + + if (ret >= 0) + { + /* Create an image of the fsinfo sector*/ + + mkfatfs_initfsinfo(fmt, var); + + /* Write the fsinfo sector */ + + ret = DEV_WRITE(var->fv_sect, FAT_DEFAULT_FSINFO_SECTOR, 1); + } + } + + return ret; +} + +/**************************************************************************** + * Name: mkfatfs_writefat + * + * Description: + * Write the FAT sectors + * + * Input: + * fmt - User specified format parameters + * var - Other format parameters that are not user specifiable + * + * Return: + * Zero on success; negated errno on failure + * + ****************************************************************************/ + +static inline int mkfatfs_writefat(FAR struct fat_format_s *fmt, + FAR struct fat_var_s *var) +{ + off_t offset = fmt->ff_rsvdseccount; + int fatno; + int sectno; + int ret; + + /* Loop for each FAT copy */ + + for (fatno = 0; fatno < fmt->ff_nfats; fatno++) + { + /* Loop for each sector in the FAT */ + + for (sectno = 0; sectno < var->fv_nfatsects; sectno++) + { + memset(var->fv_sect, 0, var->fv_sectorsize); + + /* Mark cluster allocations in sector one of each FAT */ + + if (sectno == 0) + { + memset(var->fv_sect, 0, var->fv_sectorsize); + switch(fmt->ff_fattype) + { + case 12: + /* Mark the first two full FAT entries -- 24 bits, 3 bytes total */ + + memset(var->fv_sect, 0xff, 3); + break; + + case 16: + /* Mark the first two full FAT entries -- 32 bits, 4 bytes total */ + + memset(var->fv_sect, 0xff, 4); + break; + + case 32: + default: /* Shouldn't happen */ + /* Mark the first two full FAT entries -- 64 bits, 8 bytes total */ + + memset(var->fv_sect, 0xff, 8); + + /* Cluster 2 is used as the root directory. Mark as EOF */ + + var->fv_sect[8] = 0xf8; + memset(&var->fv_sect[9], 0xff, 3); + break; + } + + /* Save the media type in the first byte of the FAT */ + + var->fv_sect[0] = FAT_DEFAULT_MEDIA_TYPE; + } + + /* Write the FAT sector */ + + ret = DEV_WRITE(var->fv_sect, offset, 1); + if (ret < 0) + { + return ret; + } + offset++; + } + } + return OK; +} + +/**************************************************************************** + * Name: mkfatfs_writerootdir + * + * Description: + * Write the root directory sectors + * + * Input: + * fmt - User specified format parameters + * var - Other format parameters that are not user specifiable + * + * Return: + * Zero on success; negated errno on failure + * + ****************************************************************************/ + +static inline int mkfatfs_writerootdir(FAR struct fat_format_s *fmt, + FAR struct fat_var_s *var) +{ + off_t offset = fmt->ff_rsvdseccount + fmt->ff_nfats * var->fv_nfatsects; + int ret; + int i; + + /* Write the root directory after the last FAT. This is the root directory + * area for FAT12/16, and the first cluster on FAT32. + */ + + for (i = 0; i < var->fv_nrootdirsects; i++) + { + /* Format the next sector of the root directory */ + + mkfatfs_initrootdir(fmt, var, i); + + /* Write the next sector of the root directory */ + + ret = DEV_WRITE(var->fv_sect, offset, 1); + if (ret < 0) + { + return ret; + } + offset++; + } + return 0; +} + +/**************************************************************************** + * Global Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: mkfatfs_writefat + * + * Description: + * Write the configured fat filesystem to the block device + * + * Input: + * fmt - Caller specified format parameters + * var - Other format parameters that are not caller specifiable. (Most + * set by mkfatfs_configfatfs()). + * + * Return: + * Zero on success; negated errno on failure + * + ****************************************************************************/ + +int mkfatfs_writefatfs(FAR struct fat_format_s *fmt, + FAR struct fat_var_s *var) +{ + int ret; + + /* Write the master boot record (also the backup and fsinfo sectors) */ + + ret = mkfatfs_writembr(fmt, var); + + /* Write FATs */ + + if (ret >= 0) + { + ret = mkfatfs_writefat(fmt, var); + } + + /* Write the root directory after the last FAT. */ + + if (ret >= 0) + { + ret = mkfatfs_writerootdir(fmt, var); + } + return ret; +} + |