/* * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see . */ /************************************************************************/ /* */ /* PROJECT : exFAT & FAT12/16/32 File System */ /* FILE : core_fat.c */ /* PURPOSE : FAT-fs core code for sdFAT */ /* */ /*----------------------------------------------------------------------*/ /* NOTES */ /* */ /* */ /************************************************************************/ #include #include #include #include #include #include "sdfat.h" #include "core.h" #include #include /*----------------------------------------------------------------------*/ /* Constant & Macro Definitions */ /*----------------------------------------------------------------------*/ #define MAX_LFN_ORDER (20) /* * MAX_EST_AU_SECT should be changed according to 32/64bits. * On 32bit, 4KB page supports 512 clusters per AU. * But, on 64bit, 4KB page can handle a half of total list_head of 32bit's. * Bcause the size of list_head structure on 64bit increases twofold over 32bit. */ #if (BITS_PER_LONG == 64) //#define MAX_EST_AU_SECT (16384) /* upto 8MB */ #define MAX_EST_AU_SECT (32768) /* upto 16MB, used more page for list_head */ #else #define MAX_EST_AU_SECT (32768) /* upto 16MB */ #endif /*======================================================================*/ /* Local Function Declarations */ /*======================================================================*/ static s32 __extract_uni_name_from_ext_entry(EXT_DENTRY_T *, u16 *, s32); /*----------------------------------------------------------------------*/ /* Global Variable Definitions */ /*----------------------------------------------------------------------*/ /*----------------------------------------------------------------------*/ /* Local Variable Definitions */ /*----------------------------------------------------------------------*/ /*======================================================================*/ /* Local Function Definitions */ /*======================================================================*/ static u32 __calc_default_au_size(struct super_block *sb) { struct block_device *bdev = sb->s_bdev; struct gendisk *disk; struct request_queue *queue; struct queue_limits *limit; unsigned int est_au_sect = MAX_EST_AU_SECT; unsigned int est_au_size = 0; unsigned int queue_au_size = 0; sector_t total_sect = 0; /* we assumed that sector size is 512 bytes */ disk = bdev->bd_disk; if (!disk) goto out; queue = disk->queue; if (!queue) goto out; limit = &queue->limits; queue_au_size = limit->discard_granularity; /* estimate function(x) = * (total_sect / 2) * 512 / 1024 * => (total_sect >> 1) >> 1) * => (total_sect >> 2) * => estimated bytes size * * ex1) <= 8GB -> 4MB * ex2) 16GB -> 8MB * ex3) >= 32GB -> 16MB */ total_sect = get_capacity(disk); est_au_size = total_sect >> 2; /* au_size assumed that bytes per sector is 512 */ est_au_sect = est_au_size >> 9; MMSG("DBG1: total_sect(%llu) est_au_size(%u) est_au_sect(%u)\n", (u64)total_sect, est_au_size, est_au_sect); if (est_au_sect <= 8192) { /* 4MB */ est_au_sect = 8192; } else if (est_au_sect <= 16384) { /* 8MB */ est_au_sect = 16384; } else { /* 8MB or 16MB */ est_au_sect = MAX_EST_AU_SECT; } MMSG("DBG2: total_sect(%llu) est_au_size(%u) est_au_sect(%u)\n", (u64)total_sect, est_au_size, est_au_sect); if (est_au_size < queue_au_size && queue_au_size <= (MAX_EST_AU_SECT << 9)) { DMSG("use queue_au_size(%u) instead of est_au_size(%u)\n", queue_au_size, est_au_size); est_au_sect = queue_au_size >> 9; } out: if (sb->s_blocksize != 512) { ASSERT(sb->s_blocksize_bits > 9); sdfat_log_msg(sb, KERN_INFO, "adjustment est_au_size by logical block size(%lu)", sb->s_blocksize); est_au_sect >>= (sb->s_blocksize_bits - 9); } sdfat_log_msg(sb, KERN_INFO, "set default AU sectors : %u " "(queue_au_size : %u KB, disk_size : %llu MB)", est_au_sect, queue_au_size >> 10, (u64)(total_sect >> 11)); return est_au_sect; } /* * Cluster Management Functions */ static s32 fat_free_cluster(struct super_block *sb, CHAIN_T *p_chain, s32 do_relse) { s32 ret = -EIO; s32 num_clusters = 0; u32 clu, prev; FS_INFO_T *fsi = &(SDFAT_SB(sb)->fsi); s32 i; u64 sector; /* invalid cluster number */ if (IS_CLUS_FREE(p_chain->dir) || IS_CLUS_EOF(p_chain->dir)) return 0; /* no cluster to truncate */ if (!p_chain->size) { DMSG("%s: cluster(%u) truncation is not required.", __func__, p_chain->dir); return 0; } /* check cluster validation */ if (!is_valid_clus(fsi, p_chain->dir)) { EMSG("%s: invalid start cluster (%u)\n", __func__, p_chain->dir); sdfat_debug_bug_on(1); return -EIO; } set_sb_dirty(sb); clu = p_chain->dir; do { if (do_relse) { sector = CLUS_TO_SECT(fsi, clu); for (i = 0; i < fsi->sect_per_clus; i++) { if (dcache_release(sb, sector+i) == -EIO) goto out; } } prev = clu; if (get_next_clus_safe(sb, &clu)) { /* print more helpful log */ if (IS_CLUS_BAD(clu)) { sdfat_log_msg(sb, KERN_ERR, "%s : " "deleting bad cluster (clu[%u]->BAD)", __func__, prev); } else if (IS_CLUS_FREE(clu)) { sdfat_log_msg(sb, KERN_ERR, "%s : " "deleting free cluster (clu[%u]->FREE)", __func__, prev); } goto out; } /* Free FAT chain */ if (fat_ent_set(sb, prev, CLUS_FREE)) goto out; /* Update AMAP if needed */ if (fsi->amap) { if (amap_release_cluster(sb, prev)) return -EIO; } num_clusters++; } while (!IS_CLUS_EOF(clu)); /* success */ ret = 0; out: fsi->used_clusters -= num_clusters; return ret; } /* end of fat_free_cluster */ static s32 fat_alloc_cluster(struct super_block *sb, u32 num_alloc, CHAIN_T *p_chain, s32 dest) { s32 ret = -ENOSPC; u32 i, num_clusters = 0, total_cnt; u32 new_clu, last_clu = CLUS_EOF, read_clu; FS_INFO_T *fsi = &(SDFAT_SB(sb)->fsi); total_cnt = fsi->num_clusters - CLUS_BASE; if (unlikely(total_cnt < fsi->used_clusters)) { sdfat_fs_error_ratelimit(sb, "%s : invalid used clusters(t:%u,u:%u)\n", __func__, total_cnt, fsi->used_clusters); return -EIO; } if (num_alloc > total_cnt - fsi->used_clusters) return -ENOSPC; new_clu = p_chain->dir; if (IS_CLUS_EOF(new_clu)) new_clu = fsi->clu_srch_ptr; else if (new_clu >= fsi->num_clusters) new_clu = CLUS_BASE; set_sb_dirty(sb); p_chain->dir = CLUS_EOF; for (i = CLUS_BASE; i < fsi->num_clusters; i++) { if (fat_ent_get(sb, new_clu, &read_clu)) { ret = -EIO; goto error; } if (IS_CLUS_FREE(read_clu)) { if (fat_ent_set(sb, new_clu, CLUS_EOF)) { ret = -EIO; goto error; } num_clusters++; if (IS_CLUS_EOF(p_chain->dir)) { p_chain->dir = new_clu; } else { if (fat_ent_set(sb, last_clu, new_clu)) { ret = -EIO; goto error; } } last_clu = new_clu; if ((--num_alloc) == 0) { fsi->clu_srch_ptr = new_clu; fsi->used_clusters += num_clusters; return 0; } } if ((++new_clu) >= fsi->num_clusters) new_clu = CLUS_BASE; } error: if (num_clusters) fat_free_cluster(sb, p_chain, 0); return ret; } /* end of fat_alloc_cluster */ static s32 fat_count_used_clusters(struct super_block *sb, u32 *ret_count) { s32 i; u32 clu, count = 0; FS_INFO_T *fsi = &(SDFAT_SB(sb)->fsi); for (i = CLUS_BASE; i < fsi->num_clusters; i++) { if (fat_ent_get(sb, i, &clu)) return -EIO; if (!IS_CLUS_FREE(clu)) count++; } *ret_count = count; return 0; } /* end of fat_count_used_clusters */ /* * Directory Entry Management Functions */ static u32 fat_get_entry_type(DENTRY_T *p_entry) { DOS_DENTRY_T *ep = (DOS_DENTRY_T *)p_entry; /* first byte of 32bytes dummy */ if (*(ep->name) == MSDOS_UNUSED) return TYPE_UNUSED; /* 0xE5 of Kanji Japanese is replaced to 0x05 */ else if (*(ep->name) == MSDOS_DELETED) return TYPE_DELETED; /* 11th byte of 32bytes dummy */ else if ((ep->attr & ATTR_EXTEND_MASK) == ATTR_EXTEND) return TYPE_EXTEND; else if (!(ep->attr & (ATTR_SUBDIR | ATTR_VOLUME))) return TYPE_FILE; else if ((ep->attr & (ATTR_SUBDIR | ATTR_VOLUME)) == ATTR_SUBDIR) return TYPE_DIR; else if ((ep->attr & (ATTR_SUBDIR | ATTR_VOLUME)) == ATTR_VOLUME) return TYPE_VOLUME; return TYPE_INVALID; } /* end of fat_get_entry_type */ static void fat_set_entry_type(DENTRY_T *p_entry, u32 type) { DOS_DENTRY_T *ep = (DOS_DENTRY_T *)p_entry; if (type == TYPE_UNUSED) *(ep->name) = MSDOS_UNUSED; /* 0x0 */ else if (type == TYPE_DELETED) *(ep->name) = MSDOS_DELETED; /* 0xE5 */ else if (type == TYPE_EXTEND) ep->attr = ATTR_EXTEND; else if (type == TYPE_DIR) ep->attr = ATTR_SUBDIR; else if (type == TYPE_FILE) ep->attr = ATTR_ARCHIVE; else if (type == TYPE_SYMLINK) ep->attr = ATTR_ARCHIVE | ATTR_SYMLINK; } /* end of fat_set_entry_type */ static u32 fat_get_entry_attr(DENTRY_T *p_entry) { DOS_DENTRY_T *ep = (DOS_DENTRY_T *)p_entry; return (u32)ep->attr; } /* end of fat_get_entry_attr */ static void fat_set_entry_attr(DENTRY_T *p_entry, u32 attr) { DOS_DENTRY_T *ep = (DOS_DENTRY_T *)p_entry; ep->attr = (u8)attr; } /* end of fat_set_entry_attr */ static u8 fat_get_entry_flag(DENTRY_T *p_entry) { return 0x01; } /* end of fat_get_entry_flag */ static void fat_set_entry_flag(DENTRY_T *p_entry, u8 flags) { } /* end of fat_set_entry_flag */ static u32 fat_get_entry_clu0(DENTRY_T *p_entry) { DOS_DENTRY_T *ep = (DOS_DENTRY_T *)p_entry; /* FIXME : is ok? */ return(((u32)(le16_to_cpu(ep->start_clu_hi)) << 16) | le16_to_cpu(ep->start_clu_lo)); } /* end of fat_get_entry_clu0 */ static void fat_set_entry_clu0(DENTRY_T *p_entry, u32 start_clu) { DOS_DENTRY_T *ep = (DOS_DENTRY_T *)p_entry; ep->start_clu_lo = cpu_to_le16(CLUSTER_16(start_clu)); ep->start_clu_hi = cpu_to_le16(CLUSTER_16(start_clu >> 16)); } /* end of fat_set_entry_clu0 */ static u64 fat_get_entry_size(DENTRY_T *p_entry) { DOS_DENTRY_T *ep = (DOS_DENTRY_T *)p_entry; return (u64)le32_to_cpu(ep->size); } /* end of fat_get_entry_size */ static void fat_set_entry_size(DENTRY_T *p_entry, u64 size) { DOS_DENTRY_T *ep = (DOS_DENTRY_T *)p_entry; ep->size = cpu_to_le32((u32)size); } /* end of fat_set_entry_size */ static void fat_get_entry_time(DENTRY_T *p_entry, TIMESTAMP_T *tp, u8 mode) { u16 t = 0x00, d = 0x21; DOS_DENTRY_T *ep = (DOS_DENTRY_T *) p_entry; switch (mode) { case TM_CREATE: t = le16_to_cpu(ep->create_time); d = le16_to_cpu(ep->create_date); break; case TM_MODIFY: t = le16_to_cpu(ep->modify_time); d = le16_to_cpu(ep->modify_date); break; } tp->tz.value = 0x00; tp->sec = (t & 0x001F) << 1; tp->min = (t >> 5) & 0x003F; tp->hour = (t >> 11); tp->day = (d & 0x001F); tp->mon = (d >> 5) & 0x000F; tp->year = (d >> 9); } /* end of fat_get_entry_time */ static void fat_set_entry_time(DENTRY_T *p_entry, TIMESTAMP_T *tp, u8 mode) { u16 t, d; DOS_DENTRY_T *ep = (DOS_DENTRY_T *) p_entry; t = (tp->hour << 11) | (tp->min << 5) | (tp->sec >> 1); d = (tp->year << 9) | (tp->mon << 5) | tp->day; switch (mode) { case TM_CREATE: ep->create_time = cpu_to_le16(t); ep->create_date = cpu_to_le16(d); break; case TM_MODIFY: ep->modify_time = cpu_to_le16(t); ep->modify_date = cpu_to_le16(d); break; } } /* end of fat_set_entry_time */ static void __init_dos_entry(struct super_block *sb, DOS_DENTRY_T *ep, u32 type, u32 start_clu) { TIMESTAMP_T tm, *tp; fat_set_entry_type((DENTRY_T *) ep, type); ep->start_clu_lo = cpu_to_le16(CLUSTER_16(start_clu)); ep->start_clu_hi = cpu_to_le16(CLUSTER_16(start_clu >> 16)); ep->size = 0; tp = tm_now_sb(sb, &tm); fat_set_entry_time((DENTRY_T *) ep, tp, TM_CREATE); fat_set_entry_time((DENTRY_T *) ep, tp, TM_MODIFY); ep->access_date = 0; ep->create_time_ms = 0; } /* end of __init_dos_entry */ static void __init_ext_entry(EXT_DENTRY_T *ep, s32 order, u8 chksum, u16 *uniname) { s32 i; u8 end = false; fat_set_entry_type((DENTRY_T *) ep, TYPE_EXTEND); ep->order = (u8) order; ep->sysid = 0; ep->checksum = chksum; ep->start_clu = 0; /* unaligned name */ for (i = 0; i < 5; i++) { if (!end) { put_unaligned_le16(*uniname, &(ep->unicode_0_4[i<<1])); if (*uniname == 0x0) end = true; else uniname++; } else { put_unaligned_le16(0xFFFF, &(ep->unicode_0_4[i<<1])); } } /* aligned name */ for (i = 0; i < 6; i++) { if (!end) { ep->unicode_5_10[i] = cpu_to_le16(*uniname); if (*uniname == 0x0) end = true; else uniname++; } else { ep->unicode_5_10[i] = cpu_to_le16(0xFFFF); } } /* aligned name */ for (i = 0; i < 2; i++) { if (!end) { ep->unicode_11_12[i] = cpu_to_le16(*uniname); if (*uniname == 0x0) end = true; else uniname++; } else { ep->unicode_11_12[i] = cpu_to_le16(0xFFFF); } } } /* end of __init_ext_entry */ static s32 fat_init_dir_entry(struct super_block *sb, CHAIN_T *p_dir, s32 entry, u32 type, u32 start_clu, u64 size) { u64 sector; DOS_DENTRY_T *dos_ep; dos_ep = (DOS_DENTRY_T *) get_dentry_in_dir(sb, p_dir, entry, §or); if (!dos_ep) return -EIO; __init_dos_entry(sb, dos_ep, type, start_clu); dcache_modify(sb, sector); return 0; } /* end of fat_init_dir_entry */ static s32 fat_init_ext_entry(struct super_block *sb, CHAIN_T *p_dir, s32 entry, s32 num_entries, UNI_NAME_T *p_uniname, DOS_NAME_T *p_dosname) { s32 i; u64 sector; u8 chksum; u16 *uniname = p_uniname->name; DOS_DENTRY_T *dos_ep; EXT_DENTRY_T *ext_ep; dos_ep = (DOS_DENTRY_T *) get_dentry_in_dir(sb, p_dir, entry, §or); if (!dos_ep) return -EIO; dos_ep->lcase = p_dosname->name_case; memcpy(dos_ep->name, p_dosname->name, DOS_NAME_LENGTH); if (dcache_modify(sb, sector)) return -EIO; if ((--num_entries) > 0) { chksum = calc_chksum_1byte((void *) dos_ep->name, DOS_NAME_LENGTH, 0); for (i = 1; i < num_entries; i++) { ext_ep = (EXT_DENTRY_T *) get_dentry_in_dir(sb, p_dir, entry-i, §or); if (!ext_ep) return -EIO; __init_ext_entry(ext_ep, i, chksum, uniname); if (dcache_modify(sb, sector)) return -EIO; uniname += 13; } ext_ep = (EXT_DENTRY_T *) get_dentry_in_dir(sb, p_dir, entry-i, §or); if (!ext_ep) return -EIO; __init_ext_entry(ext_ep, i+MSDOS_LAST_LFN, chksum, uniname); if (dcache_modify(sb, sector)) return -EIO; } return 0; } /* end of fat_init_ext_entry */ static s32 fat_delete_dir_entry(struct super_block *sb, CHAIN_T *p_dir, s32 entry, s32 order, s32 num_entries) { s32 i; u64 sector; DENTRY_T *ep; for (i = num_entries-1; i >= order; i--) { ep = get_dentry_in_dir(sb, p_dir, entry-i, §or); if (!ep) return -EIO; fat_set_entry_type(ep, TYPE_DELETED); if (dcache_modify(sb, sector)) return -EIO; } return 0; } /* return values of fat_find_dir_entry() * >= 0 : return dir entiry position with the name in dir * -EEXIST : (root dir, ".") it is the root dir itself * -ENOENT : entry with the name does not exist * -EIO : I/O error */ static inline s32 __get_dentries_per_clu(FS_INFO_T *fsi, s32 clu) { if (IS_CLUS_FREE(clu)) /* FAT16 root_dir */ return fsi->dentries_in_root; return fsi->dentries_per_clu; } static s32 fat_find_dir_entry(struct super_block *sb, FILE_ID_T *fid, CHAIN_T *p_dir, UNI_NAME_T *p_uniname, s32 num_entries, DOS_NAME_T *p_dosname, u32 type) { s32 i, rewind = 0, dentry = 0, end_eidx = 0; s32 chksum = 0, lfn_ord = 0, lfn_len = 0; s32 dentries_per_clu, num_empty = 0; u32 entry_type; u16 entry_uniname[14], *uniname = NULL; CHAIN_T clu; DENTRY_T *ep; HINT_T *hint_stat = &fid->hint_stat; HINT_FEMP_T candi_empty; FS_INFO_T *fsi = &(SDFAT_SB(sb)->fsi); /* * REMARK: * DOT and DOTDOT are handled by VFS layer */ dentries_per_clu = __get_dentries_per_clu(fsi, p_dir->dir); clu.dir = p_dir->dir; clu.flags = p_dir->flags; if (hint_stat->eidx) { clu.dir = hint_stat->clu; dentry = hint_stat->eidx; end_eidx = dentry; } candi_empty.eidx = -1; MMSG("lookup dir= %s\n", p_dosname->name); rewind: while (!IS_CLUS_EOF(clu.dir)) { i = dentry % dentries_per_clu; for (; i < dentries_per_clu; i++, dentry++) { if (rewind && (dentry == end_eidx)) goto not_found; ep = get_dentry_in_dir(sb, &clu, i, NULL); if (!ep) return -EIO; entry_type = fat_get_entry_type(ep); /* * Most directory entries have long name, * So, we check extend directory entry first. */ if (entry_type == TYPE_EXTEND) { EXT_DENTRY_T *ext_ep = (EXT_DENTRY_T *)ep; u32 cur_ord = (u32)ext_ep->order; u32 cur_chksum = (s32)ext_ep->checksum; u32 new_lfn = (cur_ord & MSDOS_LAST_LFN); s32 len = 13; u16 unichar; cur_ord &= ~(MSDOS_LAST_LFN); num_empty = 0; candi_empty.eidx = -1; /* check invalid lfn order */ if (!cur_ord || (cur_ord > MAX_LFN_ORDER)) goto reset_dentry_set; /* check whether new lfn or not */ if (new_lfn) { chksum = cur_chksum; len = (13 * (cur_ord - 1)); uniname = (p_uniname->name + len); lfn_ord = cur_ord + 1; lfn_len = 0; /* check minimum name length */ if (len > p_uniname->name_len) { /* MISMATCHED NAME LENGTH */ lfn_len = -1; } len = 0; } /* check if lfn is a consecutive number */ if ((cur_ord + 1) != lfn_ord) goto reset_dentry_set; /* check checksum of directory entry set */ if (cur_chksum != chksum) goto reset_dentry_set; /* update order for next dentry */ lfn_ord = cur_ord; /* check whether mismatched lfn or not */ if (lfn_len == -1) { /* MISMATCHED LFN DENTRY SET */ continue; } if (!uniname) { sdfat_fs_error(sb, "%s : abnormal dentry " "(start_clu[%u], " "idx[%u])", __func__, p_dir->dir, dentry); sdfat_debug_bug_on(1); return -EIO; } /* update position of name buffer */ uniname -= len; /* get utf16 characters saved on this entry */ len = __extract_uni_name_from_ext_entry(ext_ep, entry_uniname, lfn_ord); /* replace last char to null */ unichar = *(uniname+len); *(uniname+len) = (u16)0x0; /* uniname ext_dentry unit compare repeatdly */ if (nls_cmp_uniname(sb, uniname, entry_uniname)) { /* DO HANDLE WRONG NAME */ lfn_len = -1; } else { /* add matched chars length */ lfn_len += len; } /* restore previous character */ *(uniname+len) = unichar; /* jump to check next dentry */ continue; } else if ((entry_type == TYPE_FILE) || (entry_type == TYPE_DIR)) { DOS_DENTRY_T *dos_ep = (DOS_DENTRY_T *)ep; u32 cur_chksum = (s32)calc_chksum_1byte( (void *) dos_ep->name, DOS_NAME_LENGTH, 0); num_empty = 0; candi_empty.eidx = -1; MMSG("checking dir= %c%c%c%c%c%c%c%c%c%c%c\n", dos_ep->name[0], dos_ep->name[1], dos_ep->name[2], dos_ep->name[3], dos_ep->name[4], dos_ep->name[5], dos_ep->name[6], dos_ep->name[7], dos_ep->name[8], dos_ep->name[9], dos_ep->name[10]); /* * if there is no valid long filename, * we should check short filename. */ if (!lfn_len || (cur_chksum != chksum)) { /* check shortname */ if ((p_dosname->name[0] != '\0') && !nls_cmp_sfn(sb, p_dosname->name, dos_ep->name)) { goto found; } /* check name length */ } else if ((lfn_len > 0) && ((s32)p_uniname->name_len == lfn_len)) { goto found; } /* DO HANDLE MISMATCHED SFN, FALL THROUGH */ } else if ((entry_type == TYPE_UNUSED) || (entry_type == TYPE_DELETED)) { num_empty++; if (candi_empty.eidx == -1) { if (num_empty == 1) { candi_empty.cur.dir = clu.dir; candi_empty.cur.size = clu.size; candi_empty.cur.flags = clu.flags; } if (num_empty >= num_entries) { candi_empty.eidx = dentry - (num_empty - 1); ASSERT(0 <= candi_empty.eidx); candi_empty.count = num_empty; if ((fid->hint_femp.eidx == -1) || (candi_empty.eidx <= fid->hint_femp.eidx)) { memcpy(&fid->hint_femp, &candi_empty, sizeof(HINT_FEMP_T)); } } } if (entry_type == TYPE_UNUSED) goto not_found; /* FALL THROUGH */ } reset_dentry_set: /* TYPE_DELETED, TYPE_VOLUME OR MISMATCHED SFN */ lfn_ord = 0; lfn_len = 0; chksum = 0; } if (IS_CLUS_FREE(p_dir->dir)) break; /* FAT16 root_dir */ if (get_next_clus_safe(sb, &clu.dir)) return -EIO; } not_found: /* we started at not 0 index,so we should try to find target * from 0 index to the index we started at. */ if (!rewind && end_eidx) { rewind = 1; dentry = 0; clu.dir = p_dir->dir; /* reset dentry set */ lfn_ord = 0; lfn_len = 0; chksum = 0; /* reset empty hint_*/ num_empty = 0; candi_empty.eidx = -1; goto rewind; } /* initialized hint_stat */ hint_stat->clu = p_dir->dir; hint_stat->eidx = 0; return -ENOENT; found: /* next dentry we'll find is out of this cluster */ if (!((dentry + 1) % dentries_per_clu)) { int ret = 0; /* FAT16 root_dir */ if (IS_CLUS_FREE(p_dir->dir)) clu.dir = CLUS_EOF; else ret = get_next_clus_safe(sb, &clu.dir); if (ret || IS_CLUS_EOF(clu.dir)) { /* just initialized hint_stat */ hint_stat->clu = p_dir->dir; hint_stat->eidx = 0; return dentry; } } hint_stat->clu = clu.dir; hint_stat->eidx = dentry + 1; return dentry; } /* end of fat_find_dir_entry */ /* returns -EIO on error */ static s32 fat_count_ext_entries(struct super_block *sb, CHAIN_T *p_dir, s32 entry, DENTRY_T *p_entry) { s32 count = 0; u8 chksum; DOS_DENTRY_T *dos_ep = (DOS_DENTRY_T *) p_entry; EXT_DENTRY_T *ext_ep; chksum = calc_chksum_1byte((void *) dos_ep->name, DOS_NAME_LENGTH, 0); for (entry--; entry >= 0; entry--) { ext_ep = (EXT_DENTRY_T *)get_dentry_in_dir(sb, p_dir, entry, NULL); if (!ext_ep) return -EIO; if ((fat_get_entry_type((DENTRY_T *)ext_ep) == TYPE_EXTEND) && (ext_ep->checksum == chksum)) { count++; if (ext_ep->order > MSDOS_LAST_LFN) return count; } else { return count; } } return count; } /* * Name Conversion Functions */ static s32 __extract_uni_name_from_ext_entry(EXT_DENTRY_T *ep, u16 *uniname, s32 order) { s32 i, len = 0; for (i = 0; i < 5; i++) { *uniname = get_unaligned_le16(&(ep->unicode_0_4[i<<1])); if (*uniname == 0x0) return len; uniname++; len++; } if (order < 20) { for (i = 0; i < 6; i++) { /* FIXME : unaligned? */ *uniname = le16_to_cpu(ep->unicode_5_10[i]); if (*uniname == 0x0) return len; uniname++; len++; } } else { for (i = 0; i < 4; i++) { /* FIXME : unaligned? */ *uniname = le16_to_cpu(ep->unicode_5_10[i]); if (*uniname == 0x0) return len; uniname++; len++; } *uniname = 0x0; /* uniname[MAX_NAME_LENGTH] */ return len; } for (i = 0; i < 2; i++) { /* FIXME : unaligned? */ *uniname = le16_to_cpu(ep->unicode_11_12[i]); if (*uniname == 0x0) return len; uniname++; len++; } *uniname = 0x0; return len; } /* end of __extract_uni_name_from_ext_entry */ static void fat_get_uniname_from_ext_entry(struct super_block *sb, CHAIN_T *p_dir, s32 entry, u16 *uniname) { u32 i; u16 *name = uniname; u32 chksum; DOS_DENTRY_T *dos_ep = (DOS_DENTRY_T *)get_dentry_in_dir(sb, p_dir, entry, NULL); if (unlikely(!dos_ep)) goto invalid_lfn; chksum = (u32)calc_chksum_1byte( (void *) dos_ep->name, DOS_NAME_LENGTH, 0); for (entry--, i = 1; entry >= 0; entry--, i++) { EXT_DENTRY_T *ep; ep = (EXT_DENTRY_T *)get_dentry_in_dir(sb, p_dir, entry, NULL); if (!ep) goto invalid_lfn; if (fat_get_entry_type((DENTRY_T *) ep) != TYPE_EXTEND) goto invalid_lfn; if (chksum != (u32)ep->checksum) goto invalid_lfn; if (i != (u32)(ep->order & ~(MSDOS_LAST_LFN))) goto invalid_lfn; __extract_uni_name_from_ext_entry(ep, name, (s32)i); if (ep->order & MSDOS_LAST_LFN) return; name += 13; } invalid_lfn: *uniname = (u16)0x0; } /* end of fat_get_uniname_from_ext_entry */ /* Find if the shortname exists * and check if there are free entries */ static s32 __fat_find_shortname_entry(struct super_block *sb, CHAIN_T *p_dir, u8 *p_dosname, s32 *offset, __attribute__((unused))int n_entry_needed) { u32 type; s32 i, dentry = 0; s32 dentries_per_clu; DENTRY_T *ep = NULL; DOS_DENTRY_T *dos_ep = NULL; CHAIN_T clu = *p_dir; FS_INFO_T *fsi = &(SDFAT_SB(sb)->fsi); if (offset) *offset = -1; if (IS_CLUS_FREE(clu.dir)) /* FAT16 root_dir */ dentries_per_clu = fsi->dentries_in_root; else dentries_per_clu = fsi->dentries_per_clu; while (!IS_CLUS_EOF(clu.dir)) { for (i = 0; i < dentries_per_clu; i++, dentry++) { ep = get_dentry_in_dir(sb, &clu, i, NULL); if (!ep) return -EIO; type = fat_get_entry_type(ep); if ((type == TYPE_FILE) || (type == TYPE_DIR)) { dos_ep = (DOS_DENTRY_T *)ep; if (!nls_cmp_sfn(sb, p_dosname, dos_ep->name)) { if (offset) *offset = dentry; return 0; } } } /* fat12/16 root dir */ if (IS_CLUS_FREE(clu.dir)) break; if (get_next_clus_safe(sb, &clu.dir)) return -EIO; } return -ENOENT; } #ifdef CONFIG_SDFAT_FAT32_SHORTNAME_SEQ static void __fat_attach_count_to_dos_name(u8 *dosname, s32 count) { s32 i, j, length; s8 str_count[6]; snprintf(str_count, sizeof(str_count), "~%d", count); length = strlen(str_count); i = j = 0; while (j <= (8 - length)) { i = j; if (dosname[j] == ' ') break; if (dosname[j] & 0x80) j += 2; else j++; } for (j = 0; j < length; i++, j++) dosname[i] = (u8) str_count[j]; if (i == 7) dosname[7] = ' '; } /* end of __fat_attach_count_to_dos_name */ #endif s32 fat_generate_dos_name_new(struct super_block *sb, CHAIN_T *p_dir, DOS_NAME_T *p_dosname, s32 n_entry_needed) { s32 i; s32 baselen, err; u8 work[DOS_NAME_LENGTH], buf[5]; u8 tail; baselen = 8; memset(work, ' ', DOS_NAME_LENGTH); memcpy(work, p_dosname->name, DOS_NAME_LENGTH); while (baselen && (work[--baselen] == ' ')) { /* DO NOTHING, JUST FOR CHECK_PATCH */ } if (baselen > 6) baselen = 6; BUG_ON(baselen < 0); #ifdef CONFIG_SDFAT_FAT32_SHORTNAME_SEQ /* example) namei_exfat.c -> NAMEI_~1 - NAMEI_~9 */ work[baselen] = '~'; for (i = 1; i < 10; i++) { // '0' + i = 1 ~ 9 ASCII work[baselen + 1] = '0' + i; err = __fat_find_shortname_entry(sb, p_dir, work, NULL, n_entry_needed); if (err == -ENOENT) { /* void return */ __fat_attach_count_to_dos_name(p_dosname->name, i); return 0; } /* any other error */ if (err) return err; } #endif i = jiffies; tail = (jiffies >> 16) & 0x7; if (baselen > 2) baselen = 2; BUG_ON(baselen < 0); work[baselen + 4] = '~'; // 1 ~ 8 ASCII work[baselen + 5] = '1' + tail; while (1) { snprintf(buf, sizeof(buf), "%04X", i & 0xffff); memcpy(&work[baselen], buf, 4); err = __fat_find_shortname_entry(sb, p_dir, work, NULL, n_entry_needed); if (err == -ENOENT) { memcpy(p_dosname->name, work, DOS_NAME_LENGTH); break; } /* any other error */ if (err) return err; i -= 11; } return 0; } /* end of generate_dos_name_new */ static s32 fat_calc_num_entries(UNI_NAME_T *p_uniname) { s32 len; len = p_uniname->name_len; if (len == 0) return 0; /* 1 dos name entry + extended entries */ return((len-1) / 13 + 2); } /* end of calc_num_enties */ static s32 fat_check_max_dentries(FILE_ID_T *fid) { if ((fid->size >> DENTRY_SIZE_BITS) >= MAX_FAT_DENTRIES) { /* FAT spec allows a dir to grow upto 65536 dentries */ return -ENOSPC; } return 0; } /* end of check_max_dentries */ /* * File Operation Functions */ static FS_FUNC_T fat_fs_func = { .alloc_cluster = fat_alloc_cluster, .free_cluster = fat_free_cluster, .count_used_clusters = fat_count_used_clusters, .init_dir_entry = fat_init_dir_entry, .init_ext_entry = fat_init_ext_entry, .find_dir_entry = fat_find_dir_entry, .delete_dir_entry = fat_delete_dir_entry, .get_uniname_from_ext_entry = fat_get_uniname_from_ext_entry, .count_ext_entries = fat_count_ext_entries, .calc_num_entries = fat_calc_num_entries, .check_max_dentries = fat_check_max_dentries, .get_entry_type = fat_get_entry_type, .set_entry_type = fat_set_entry_type, .get_entry_attr = fat_get_entry_attr, .set_entry_attr = fat_set_entry_attr, .get_entry_flag = fat_get_entry_flag, .set_entry_flag = fat_set_entry_flag, .get_entry_clu0 = fat_get_entry_clu0, .set_entry_clu0 = fat_set_entry_clu0, .get_entry_size = fat_get_entry_size, .set_entry_size = fat_set_entry_size, .get_entry_time = fat_get_entry_time, .set_entry_time = fat_set_entry_time, }; static FS_FUNC_T amap_fat_fs_func = { .alloc_cluster = amap_fat_alloc_cluster, .free_cluster = fat_free_cluster, .count_used_clusters = fat_count_used_clusters, .init_dir_entry = fat_init_dir_entry, .init_ext_entry = fat_init_ext_entry, .find_dir_entry = fat_find_dir_entry, .delete_dir_entry = fat_delete_dir_entry, .get_uniname_from_ext_entry = fat_get_uniname_from_ext_entry, .count_ext_entries = fat_count_ext_entries, .calc_num_entries = fat_calc_num_entries, .check_max_dentries = fat_check_max_dentries, .get_entry_type = fat_get_entry_type, .set_entry_type = fat_set_entry_type, .get_entry_attr = fat_get_entry_attr, .set_entry_attr = fat_set_entry_attr, .get_entry_flag = fat_get_entry_flag, .set_entry_flag = fat_set_entry_flag, .get_entry_clu0 = fat_get_entry_clu0, .set_entry_clu0 = fat_set_entry_clu0, .get_entry_size = fat_get_entry_size, .set_entry_size = fat_set_entry_size, .get_entry_time = fat_get_entry_time, .set_entry_time = fat_set_entry_time, .get_au_stat = amap_get_au_stat, }; static s32 mount_fat_common(struct super_block *sb, FS_INFO_T *fsi, bpb_t *p_bpb, u32 root_sects) { bool fat32 = root_sects == 0 ? true : false; fsi->sect_per_clus = p_bpb->sect_per_clus; if (!is_power_of_2(fsi->sect_per_clus)) { sdfat_msg(sb, KERN_ERR, "bogus sectors per cluster %u", fsi->sect_per_clus); return -EINVAL; } fsi->sect_per_clus_bits = ilog2(p_bpb->sect_per_clus); fsi->cluster_size_bits = fsi->sect_per_clus_bits + sb->s_blocksize_bits; fsi->cluster_size = 1 << fsi->cluster_size_bits; fsi->dentries_per_clu = 1 << (fsi->cluster_size_bits - DENTRY_SIZE_BITS); fsi->vol_flag = VOL_CLEAN; fsi->clu_srch_ptr = CLUS_BASE; fsi->used_clusters = (u32)~0; fsi->fs_func = &fat_fs_func; fsi->num_FAT_sectors = le16_to_cpu(p_bpb->num_fat_sectors); if (fat32) { u32 fat32_len = le32_to_cpu(p_bpb->f32.num_fat32_sectors); if (fat32_len) { fsi->num_FAT_sectors = fat32_len; } else if (fsi->num_FAT_sectors) { /* SPEC violation for compatibility */ sdfat_msg(sb, KERN_WARNING, "no fatsz32, try with fatsz16: %u", fsi->num_FAT_sectors); } } if (!fsi->num_FAT_sectors) { sdfat_msg(sb, KERN_ERR, "bogus fat size"); return -EINVAL; } if (!p_bpb->num_fats) { sdfat_msg(sb, KERN_ERR, "bogus number of FAT structure"); return -EINVAL; } if (p_bpb->num_fats > 2) { sdfat_msg(sb, KERN_WARNING, "unsupported number of FAT structure :%u, try with 2", p_bpb->num_fats); } fsi->FAT1_start_sector = le16_to_cpu(p_bpb->num_reserved); if (p_bpb->num_fats == 1) fsi->FAT2_start_sector = fsi->FAT1_start_sector; else fsi->FAT2_start_sector = fsi->FAT1_start_sector + fsi->num_FAT_sectors; fsi->root_start_sector = fsi->FAT2_start_sector + fsi->num_FAT_sectors; fsi->data_start_sector = fsi->root_start_sector + root_sects; /* SPEC violation for compatibility */ fsi->num_sectors = get_unaligned_le16(p_bpb->num_sectors); if (!fsi->num_sectors) fsi->num_sectors = le32_to_cpu(p_bpb->num_huge_sectors); if (!fsi->num_sectors) { sdfat_msg(sb, KERN_ERR, "bogus number of total sector count"); return -EINVAL; } /* because the cluster index starts with 2 */ fsi->num_clusters = (u32)((fsi->num_sectors - fsi->data_start_sector) >> fsi->sect_per_clus_bits) + CLUS_BASE; return 0; } s32 mount_fat16(struct super_block *sb, pbr_t *p_pbr) { u32 num_root_sectors; bpb_t *p_bpb = &(p_pbr->bpb.fat); FS_INFO_T *fsi = &(SDFAT_SB(sb)->fsi); fsi->vol_id = get_unaligned_le32(p_bpb->f16.vol_serial); fsi->root_dir = 0; fsi->dentries_in_root = get_unaligned_le16(p_bpb->num_root_entries); if (!fsi->dentries_in_root) { sdfat_msg(sb, KERN_ERR, "bogus number of max dentry count " "of the root directory"); return -EINVAL; } num_root_sectors = fsi->dentries_in_root << DENTRY_SIZE_BITS; num_root_sectors = ((num_root_sectors - 1) >> sb->s_blocksize_bits) + 1; if (mount_fat_common(sb, fsi, p_bpb, num_root_sectors)) return -EINVAL; fsi->vol_type = FAT16; if (fsi->num_clusters < FAT12_THRESHOLD) fsi->vol_type = FAT12; fat_ent_ops_init(sb); if (p_bpb->f16.state & FAT_VOL_DIRTY) { fsi->vol_flag |= VOL_DIRTY; sdfat_log_msg(sb, KERN_WARNING, "Volume was not properly " "unmounted. Some data may be corrupt. " "Please run fsck."); } return 0; } /* end of mount_fat16 */ #if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 11, 0) static u8 bdev_get_partno(struct block_device *bdev) { return bdev->bd_partno; } #else static struct block_device *bdev_whole(struct block_device *bdev) { return bdev->bd_contains; } static u8 bdev_get_partno(struct block_device *bdev) { return bdev->bd_part->partno; } #endif static sector_t __calc_hidden_sect(struct super_block *sb) { struct block_device *bdev = sb->s_bdev; sector_t hidden = 0; if (!bdev) goto out; hidden = get_start_sect(bdev); /* a disk device, not a partition */ if (!hidden) { if (bdev != bdev_whole(bdev)) sdfat_log_msg(sb, KERN_WARNING, "hidden(0), but disk has a partition table"); goto out; } if (sb->s_blocksize_bits != 9) { ASSERT(sb->s_blocksize_bits > 9); hidden >>= (sb->s_blocksize_bits - 9); } out: sdfat_log_msg(sb, KERN_INFO, "start_sect of part(%d) : %lld", bdev ? bdev_get_partno(bdev) : -1, (s64)hidden); return hidden; } s32 mount_fat32(struct super_block *sb, pbr_t *p_pbr) { pbr32_t *p_bpb = (pbr32_t *)p_pbr; FS_INFO_T *fsi = &(SDFAT_SB(sb)->fsi); fsi->vol_id = get_unaligned_le32(p_bpb->bsx.vol_serial); fsi->root_dir = le32_to_cpu(p_bpb->bpb.f32.root_cluster); fsi->dentries_in_root = 0; if (mount_fat_common(sb, fsi, &p_bpb->bpb, 0)) return -EINVAL; /* Should be initialized before calling amap_create() */ fsi->vol_type = FAT32; fat_ent_ops_init(sb); /* Delayed / smart allocation related init */ fsi->reserved_clusters = 0; /* AU Map Creation */ if (SDFAT_SB(sb)->options.improved_allocation & SDFAT_ALLOC_SMART) { u32 hidden_sectors = le32_to_cpu(p_bpb->bpb.num_hid_sectors); u32 calc_hid_sect = 0; int ret; /* calculate hidden sector size */ calc_hid_sect = __calc_hidden_sect(sb); if (calc_hid_sect != hidden_sectors) { sdfat_log_msg(sb, KERN_WARNING, "abnormal hidden " "sector : bpb(%u) != ondisk(%u)", hidden_sectors, calc_hid_sect); if (SDFAT_SB(sb)->options.adj_hidsect) { sdfat_log_msg(sb, KERN_INFO, "adjustment hidden sector : " "bpb(%u) -> ondisk(%u)", hidden_sectors, calc_hid_sect); hidden_sectors = calc_hid_sect; } } SDFAT_SB(sb)->options.amap_opt.misaligned_sect = hidden_sectors; /* calculate AU size if it's not set */ if (!SDFAT_SB(sb)->options.amap_opt.sect_per_au) { SDFAT_SB(sb)->options.amap_opt.sect_per_au = __calc_default_au_size(sb); } ret = amap_create(sb, SDFAT_SB(sb)->options.amap_opt.pack_ratio, SDFAT_SB(sb)->options.amap_opt.sect_per_au, SDFAT_SB(sb)->options.amap_opt.misaligned_sect); if (ret) { sdfat_log_msg(sb, KERN_WARNING, "failed to create AMAP." " disabling smart allocation. (err:%d)", ret); SDFAT_SB(sb)->options.improved_allocation &= ~(SDFAT_ALLOC_SMART); } else { fsi->fs_func = &amap_fat_fs_func; } } /* Check dependency of mount options */ if (SDFAT_SB(sb)->options.improved_allocation != (SDFAT_ALLOC_DELAY | SDFAT_ALLOC_SMART)) { sdfat_log_msg(sb, KERN_INFO, "disabling defragmentation because" " smart, delay options are disabled"); SDFAT_SB(sb)->options.defrag = 0; } if (p_bpb->bsx.state & FAT_VOL_DIRTY) { fsi->vol_flag |= VOL_DIRTY; sdfat_log_msg(sb, KERN_WARNING, "Volume was not properly " "unmounted. Some data may be corrupt. " "Please run fsck."); } return 0; } /* end of mount_fat32 */ /* end of core_fat.c */