diff options
Diffstat (limited to 'fs/fat')
| -rw-r--r-- | fs/fat/fat.c | 67 | ||||
| -rw-r--r-- | fs/fat/fat_write.c | 1185 |
2 files changed, 818 insertions, 434 deletions
diff --git a/fs/fat/fat.c b/fs/fat/fat.c index 4b722fc5ca..b08949d370 100644 --- a/fs/fat/fat.c +++ b/fs/fat/fat.c @@ -260,7 +260,7 @@ get_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size) if ((unsigned long)buffer & (ARCH_DMA_MINALIGN - 1)) { ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size); - printf("FAT: Misaligned buffer address (%p)\n", buffer); + debug("FAT: Misaligned buffer address (%p)\n", buffer); while (size >= mydata->sect_size) { ret = disk_read(startsect++, 1, tmpbuf); @@ -465,15 +465,6 @@ static __u8 mkcksum(const char name[8], const char ext[3]) } /* - * TODO these should go away once fat_write is reworked to use the - * directory iterator - */ -__u8 get_dentfromdir_block[MAX_CLUSTSIZE] - __aligned(ARCH_DMA_MINALIGN); -__u8 do_fat_read_at_block[MAX_CLUSTSIZE] - __aligned(ARCH_DMA_MINALIGN); - -/* * Read boot sector and volume info from a FAT filesystem */ static int @@ -558,10 +549,17 @@ static int get_fs_info(fsdata *mydata) if (mydata->fatsize == 32) { mydata->fatlength = bs.fat32_length; + mydata->total_sect = bs.total_sect; } else { mydata->fatlength = bs.fat_length; + mydata->total_sect = (bs.sectors[1] << 8) + bs.sectors[0]; + if (!mydata->total_sect) + mydata->total_sect = bs.total_sect; } + if (!mydata->total_sect) /* unlikely */ + mydata->total_sect = (u32)cur_part_info.size; + mydata->fats = bs.fats; mydata->fat_sect = bs.reserved; mydata->rootdir_sect = mydata->fat_sect + mydata->fatlength * bs.fats; @@ -633,7 +631,9 @@ static int get_fs_info(fsdata *mydata) typedef struct { fsdata *fsdata; /* filesystem parameters */ + unsigned start_clust; /* first cluster */ unsigned clust; /* current cluster */ + unsigned next_clust; /* next cluster if remaining == 0 */ int last_cluster; /* set once we've read last cluster */ int is_root; /* is iterator at root directory */ int remaining; /* remaining dent's in current cluster */ @@ -664,7 +664,9 @@ static int fat_itr_root(fat_itr *itr, fsdata *fsdata) return -ENXIO; itr->fsdata = fsdata; + itr->start_clust = 0; itr->clust = fsdata->root_cluster; + itr->next_clust = fsdata->root_cluster; itr->dent = NULL; itr->remaining = 0; itr->last_cluster = 0; @@ -698,11 +700,14 @@ static void fat_itr_child(fat_itr *itr, fat_itr *parent) assert(fat_itr_isdir(parent)); itr->fsdata = parent->fsdata; + itr->start_clust = clustnum; if (clustnum > 0) { itr->clust = clustnum; + itr->next_clust = clustnum; itr->is_root = 0; } else { itr->clust = parent->fsdata->root_cluster; + itr->next_clust = parent->fsdata->root_cluster; itr->is_root = 1; } itr->dent = NULL; @@ -720,7 +725,7 @@ static void *next_cluster(fat_itr *itr) if (itr->last_cluster) return NULL; - sect = clust_to_sect(itr->fsdata, itr->clust); + sect = clust_to_sect(itr->fsdata, itr->next_clust); debug("FAT read(sect=%d), clust_size=%d, DIRENTSPERBLOCK=%zd\n", sect, itr->fsdata->clust_size, DIRENTSPERBLOCK); @@ -741,18 +746,19 @@ static void *next_cluster(fat_itr *itr) return NULL; } + itr->clust = itr->next_clust; if (itr->is_root && itr->fsdata->fatsize != 32) { - itr->clust++; - sect = clust_to_sect(itr->fsdata, itr->clust); + itr->next_clust++; + sect = clust_to_sect(itr->fsdata, itr->next_clust); if (sect - itr->fsdata->rootdir_sect >= itr->fsdata->rootdir_size) { - debug("cursect: 0x%x\n", itr->clust); + debug("nextclust: 0x%x\n", itr->next_clust); itr->last_cluster = 1; } } else { - itr->clust = get_fatent(itr->fsdata, itr->clust); - if (CHECK_CLUST(itr->clust, itr->fsdata->fatsize)) { - debug("cursect: 0x%x\n", itr->clust); + itr->next_clust = get_fatent(itr->fsdata, itr->next_clust); + if (CHECK_CLUST(itr->next_clust, itr->fsdata->fatsize)) { + debug("nextclust: 0x%x\n", itr->next_clust); itr->last_cluster = 1; } } @@ -768,8 +774,11 @@ static dir_entry *next_dent(fat_itr *itr) itr->fsdata->clust_size; /* have we reached the last cluster? */ - if (!dent) + if (!dent) { + /* a sign for no more entries left */ + itr->dent = NULL; return NULL; + } itr->remaining = nbytes / sizeof(dir_entry) - 1; itr->dent = dent; @@ -924,6 +933,28 @@ static int fat_itr_resolve(fat_itr *itr, const char *path, unsigned type) while (next[0] && !ISDIRDELIM(next[0])) next++; + if (itr->is_root) { + /* root dir doesn't have "." nor ".." */ + if ((((next - path) == 1) && !strncmp(path, ".", 1)) || + (((next - path) == 2) && !strncmp(path, "..", 2))) { + /* point back to itself */ + itr->clust = itr->fsdata->root_cluster; + itr->next_clust = itr->fsdata->root_cluster; + itr->dent = NULL; + itr->remaining = 0; + itr->last_cluster = 0; + + if (next[0] == 0) { + if (type & TYPE_DIR) + return 0; + else + return -ENOENT; + } + + return fat_itr_resolve(itr, next, type); + } + } + while (fat_itr_next(itr)) { int match = 0; unsigned n = max(strlen(itr->name), (size_t)(next - path)); diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c index 27e0ff6696..fc211e74bc 100644 --- a/fs/fat/fat_write.c +++ b/fs/fat/fat_write.c @@ -99,7 +99,6 @@ static void set_name(dir_entry *dirent, const char *filename) debug("ext : %s\n", dirent->ext); } -static __u8 num_of_fats; /* * Write fat buffer into block device */ @@ -128,7 +127,7 @@ static int flush_dirty_fat_buffer(fsdata *mydata) return -1; } - if (num_of_fats == 2) { + if (mydata->fats == 2) { /* Update corresponding second FAT blocks */ startblock += mydata->fatlength; if (disk_write(startblock, getsize, bufptr) < 0) { @@ -210,15 +209,14 @@ name11_12: return 1; } -static int is_next_clust(fsdata *mydata, dir_entry *dentptr); -static void flush_dir_table(fsdata *mydata, dir_entry **dentptr); +static int flush_dir_table(fat_itr *itr); /* * Fill dir_slot entries with appropriate name, id, and attr - * The real directory entry is returned by 'dentptr' + * 'itr' will point to a next entry */ -static void -fill_dir_slot(fsdata *mydata, dir_entry **dentptr, const char *l_name) +static int +fill_dir_slot(fat_itr *itr, const char *l_name) { __u8 temp_dir_slot_buffer[MAX_LFN_SLOT * sizeof(dir_slot)]; dir_slot *slotptr = (dir_slot *)temp_dir_slot_buffer; @@ -226,7 +224,7 @@ fill_dir_slot(fsdata *mydata, dir_entry **dentptr, const char *l_name) int idx = 0, ret; /* Get short file name checksum value */ - checksum = mkcksum((*dentptr)->name, (*dentptr)->ext); + checksum = mkcksum(itr->dent->name, itr->dent->ext); do { memset(slotptr, 0x00, sizeof(dir_slot)); @@ -241,120 +239,21 @@ fill_dir_slot(fsdata *mydata, dir_entry **dentptr, const char *l_name) slotptr->id |= LAST_LONG_ENTRY_MASK; while (counter >= 1) { - if (is_next_clust(mydata, *dentptr)) { - /* A new cluster is allocated for directory table */ - flush_dir_table(mydata, dentptr); - } - memcpy(*dentptr, slotptr, sizeof(dir_slot)); - (*dentptr)++; + memcpy(itr->dent, slotptr, sizeof(dir_slot)); slotptr--; counter--; - } - - if (is_next_clust(mydata, *dentptr)) { - /* A new cluster is allocated for directory table */ - flush_dir_table(mydata, dentptr); - } -} - -static __u32 dir_curclust; - -/* - * Extract the full long filename starting at 'retdent' (which is really - * a slot) into 'l_name'. If successful also copy the real directory entry - * into 'retdent' - * If additional adjacent cluster for directory entries is read into memory, - * then 'get_contents_vfatname_block' is copied into 'get_dentfromdir_block' and - * the location of the real directory entry is returned by 'retdent' - * Return 0 on success, -1 otherwise. - */ -static int -get_long_file_name(fsdata *mydata, int curclust, __u8 *cluster, - dir_entry **retdent, char *l_name) -{ - dir_entry *realdent; - dir_slot *slotptr = (dir_slot *)(*retdent); - dir_slot *slotptr2 = NULL; - __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ? - PREFETCH_BLOCKS : - mydata->clust_size); - __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff; - int idx = 0, cur_position = 0; - - if (counter > VFAT_MAXSEQ) { - debug("Error: VFAT name is too long\n"); - return -1; - } - - while ((__u8 *)slotptr < buflimit) { - if (counter == 0) - break; - if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter) - return -1; - slotptr++; - counter--; - } - - if ((__u8 *)slotptr >= buflimit) { - if (curclust == 0) - return -1; - curclust = get_fatent(mydata, dir_curclust); - if (CHECK_CLUST(curclust, mydata->fatsize)) { - debug("curclust: 0x%x\n", curclust); - printf("Invalid FAT entry\n"); - return -1; - } - - dir_curclust = curclust; - - if (get_cluster(mydata, curclust, get_contents_vfatname_block, - mydata->clust_size * mydata->sect_size) != 0) { - debug("Error: reading directory block\n"); - return -1; - } - - slotptr2 = (dir_slot *)get_contents_vfatname_block; - while (counter > 0) { - if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK) - & 0xff) != counter) + if (!fat_itr_next(itr)) + if (!itr->dent && !itr->is_root && flush_dir_table(itr)) return -1; - slotptr2++; - counter--; - } - - /* Save the real directory entry */ - realdent = (dir_entry *)slotptr2; - while ((__u8 *)slotptr2 > get_contents_vfatname_block) { - slotptr2--; - slot2str(slotptr2, l_name, &idx); - } - } else { - /* Save the real directory entry */ - realdent = (dir_entry *)slotptr; } - do { - slotptr--; - if (slot2str(slotptr, l_name, &idx)) - break; - } while (!(slotptr->id & LAST_LONG_ENTRY_MASK)); - - l_name[idx] = '\0'; - if (*l_name == DELETED_FLAG) - *l_name = '\0'; - else if (*l_name == aRING) - *l_name = DELETED_FLAG; - downcase(l_name, INT_MAX); - - /* Return the real directory entry */ - *retdent = realdent; - - if (slotptr2) { - memcpy(get_dentfromdir_block, get_contents_vfatname_block, - mydata->clust_size * mydata->sect_size); - cur_position = (__u8 *)realdent - get_contents_vfatname_block; - *retdent = (dir_entry *) &get_dentfromdir_block[cur_position]; - } + if (!itr->dent && !itr->is_root) + /* + * don't care return value here because we have already + * finished completing an entry with name, only ending up + * no more entry left + */ + flush_dir_table(itr); return 0; } @@ -510,7 +409,7 @@ set_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, if ((unsigned long)buffer & (ARCH_DMA_MINALIGN - 1)) { ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size); - printf("FAT: Misaligned buffer address (%p)\n", buffer); + debug("FAT: Misaligned buffer address (%p)\n", buffer); while (size >= mydata->sect_size) { memcpy(tmpbuf, buffer, mydata->sect_size); @@ -551,6 +450,121 @@ set_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, return 0; } +static __u8 tmpbuf_cluster[MAX_CLUSTSIZE] __aligned(ARCH_DMA_MINALIGN); + +/* + * Read and modify data on existing and consecutive cluster blocks + */ +static int +get_set_cluster(fsdata *mydata, __u32 clustnum, loff_t pos, __u8 *buffer, + loff_t size, loff_t *gotsize) +{ + unsigned int bytesperclust = mydata->clust_size * mydata->sect_size; + __u32 startsect; + loff_t wsize; + int clustcount, i, ret; + + *gotsize = 0; + if (!size) + return 0; + + assert(pos < bytesperclust); + startsect = clust_to_sect(mydata, clustnum); + + debug("clustnum: %d, startsect: %d, pos: %lld\n", + clustnum, startsect, pos); + + /* partial write at beginning */ + if (pos) { + wsize = min(bytesperclust - pos, size); + ret = disk_read(startsect, mydata->clust_size, tmpbuf_cluster); + if (ret != mydata->clust_size) { + debug("Error reading data (got %d)\n", ret); + return -1; + } + + memcpy(tmpbuf_cluster + pos, buffer, wsize); + ret = disk_write(startsect, mydata->clust_size, tmpbuf_cluster); + if (ret != mydata->clust_size) { + debug("Error writing data (got %d)\n", ret); + return -1; + } + + size -= wsize; + buffer += wsize; + *gotsize += wsize; + + startsect += mydata->clust_size; + + if (!size) + return 0; + } + + /* full-cluster write */ + if (size >= bytesperclust) { + clustcount = lldiv(size, bytesperclust); + + if (!((unsigned long)buffer & (ARCH_DMA_MINALIGN - 1))) { + wsize = clustcount * bytesperclust; + ret = disk_write(startsect, + clustcount * mydata->clust_size, + buffer); + if (ret != clustcount * mydata->clust_size) { + debug("Error writing data (got %d)\n", ret); + return -1; + } + + size -= wsize; + buffer += wsize; + *gotsize += wsize; + + startsect += clustcount * mydata->clust_size; + } else { + for (i = 0; i < clustcount; i++) { + memcpy(tmpbuf_cluster, buffer, bytesperclust); + ret = disk_write(startsect, + mydata->clust_size, + tmpbuf_cluster); + if (ret != mydata->clust_size) { + debug("Error writing data (got %d)\n", + ret); + return -1; + } + + size -= bytesperclust; + buffer += bytesperclust; + *gotsize += bytesperclust; + + startsect += mydata->clust_size; + } + } + } + + /* partial write at end */ + if (size) { + wsize = size; + ret = disk_read(startsect, mydata->clust_size, tmpbuf_cluster); + if (ret != mydata->clust_size) { + debug("Error reading data (got %d)\n", ret); + return -1; + } + memcpy(tmpbuf_cluster, buffer, wsize); + ret = disk_write(startsect, mydata->clust_size, tmpbuf_cluster); + if (ret != mydata->clust_size) { + debug("Error writing data (got %d)\n", ret); + return -1; + } + + size -= wsize; + buffer += wsize; + *gotsize += wsize; + } + + assert(!size); + + return 0; +} + /* * Find the first empty cluster */ @@ -569,20 +583,20 @@ static int find_empty_cluster(fsdata *mydata) } /* - * Write directory entries in 'get_dentfromdir_block' to block device + * Write directory entries in itr's buffer to block device */ -static void flush_dir_table(fsdata *mydata, dir_entry **dentptr) +static int flush_dir_table(fat_itr *itr) { + fsdata *mydata = itr->fsdata; int dir_newclust = 0; + unsigned int bytesperclust = mydata->clust_size * mydata->sect_size; - if (set_cluster(mydata, dir_curclust, - get_dentfromdir_block, - mydata->clust_size * mydata->sect_size) != 0) { - printf("error: wrinting directory entry\n"); - return; + if (set_cluster(mydata, itr->clust, itr->block, bytesperclust) != 0) { + printf("error: writing directory entry\n"); + return -1; } dir_newclust = find_empty_cluster(mydata); - set_fatent_value(mydata, dir_curclust, dir_newclust); + set_fatent_value(mydata, itr->clust, dir_newclust); if (mydata->fatsize == 32) set_fatent_value(mydata, dir_newclust, 0xffffff8); else if (mydata->fatsize == 16) @@ -590,15 +604,19 @@ static void flush_dir_table(fsdata *mydata, dir_entry **dentptr) else if (mydata->fatsize == 12) set_fatent_value(mydata, dir_newclust, 0xff8); - dir_curclust = dir_newclust; + itr->clust = dir_newclust; + itr->next_clust = dir_newclust; if (flush_dirty_fat_buffer(mydata) < 0) - return; + return -1; - memset(get_dentfromdir_block, 0x00, - mydata->clust_size * mydata->sect_size); + memset(itr->block, 0x00, bytesperclust); - *dentptr = (dir_entry *) get_dentfromdir_block; + itr->dent = (dir_entry *)itr->block; + itr->last_cluster = 1; + itr->remaining = bytesperclust / sizeof(dir_entry) - 1; + + return 0; } /* @@ -626,37 +644,212 @@ static int clear_fatent(fsdata *mydata, __u32 entry) } /* + * Set start cluster in directory entry + */ +static void set_start_cluster(const fsdata *mydata, dir_entry *dentptr, + __u32 start_cluster) +{ + if (mydata->fatsize == 32) + dentptr->starthi = + cpu_to_le16((start_cluster & 0xffff0000) >> 16); + dentptr->start = cpu_to_le16(start_cluster & 0xffff); +} + +/* + * Check whether adding a file makes the file system to + * exceed the size of the block device + * Return -1 when overflow occurs, otherwise return 0 + */ +static int check_overflow(fsdata *mydata, __u32 clustnum, loff_t size) +{ + __u32 startsect, sect_num, offset; + + if (clustnum > 0) + startsect = clust_to_sect(mydata, clustnum); + else + startsect = mydata->rootdir_sect; + + sect_num = div_u64_rem(size, mydata->sect_size, &offset); + + if (offset != 0) + sect_num++; + + if (startsect + sect_num > total_sector) + return -1; + return 0; +} + +/* * Write at most 'maxsize' bytes from 'buffer' into * the file associated with 'dentptr' * Update the number of bytes written in *gotsize and return 0 * or return -1 on fatal errors. */ static int -set_contents(fsdata *mydata, dir_entry *dentptr, __u8 *buffer, - loff_t maxsize, loff_t *gotsize) +set_contents(fsdata *mydata, dir_entry *dentptr, loff_t pos, __u8 *buffer, + loff_t maxsize, loff_t *gotsize) { - loff_t filesize = FAT2CPU32(dentptr->size); + loff_t filesize; unsigned int bytesperclust = mydata->clust_size * mydata->sect_size; __u32 curclust = START(dentptr); __u32 endclust = 0, newclust = 0; - loff_t actsize; + loff_t cur_pos, offset, actsize, wsize; *gotsize = 0; - debug("Filesize: %llu bytes\n", filesize); - - if (maxsize > 0 && filesize > maxsize) - filesize = maxsize; + filesize = pos + maxsize; debug("%llu bytes\n", filesize); + if (!filesize) { + if (!curclust) + return 0; + if (!CHECK_CLUST(curclust, mydata->fatsize) || + IS_LAST_CLUST(curclust, mydata->fatsize)) { + clear_fatent(mydata, curclust); + set_start_cluster(mydata, dentptr, 0); + return 0; + } + debug("curclust: 0x%x\n", curclust); + debug("Invalid FAT entry\n"); + return -1; + } + if (!curclust) { - if (filesize) { - debug("error: nonempty clusterless file!\n"); + assert(pos == 0); + goto set_clusters; + } + + /* go to cluster at pos */ + cur_pos = bytesperclust; + while (1) { + if (pos <= cur_pos) + break; + if (IS_LAST_CLUST(curclust, mydata->fatsize)) + break; + + newclust = get_fatent(mydata, curclust); + if (!IS_LAST_CLUST(newclust, mydata->fatsize) && + CHECK_CLUST(newclust, mydata->fatsize)) { + debug("curclust: 0x%x\n", curclust); + debug("Invalid FAT entry\n"); return -1; } + + cur_pos += bytesperclust; + curclust = newclust; + } + if (IS_LAST_CLUST(curclust, mydata->fatsize)) { + assert(pos == cur_pos); + goto set_clusters; + } + + assert(pos < cur_pos); + cur_pos -= bytesperclust; + + /* overwrite */ + assert(IS_LAST_CLUST(curclust, mydata->fatsize) || + !CHECK_CLUST(curclust, mydata->fatsize)); + + while (1) { + /* search for allocated consecutive clusters */ + actsize = bytesperclust; + endclust = curclust; + while (1) { + if (filesize <= (cur_pos + actsize)) + break; + + newclust = get_fatent(mydata, endclust); + + if (IS_LAST_CLUST(newclust, mydata->fatsize)) + break; + if (CHECK_CLUST(newclust, mydata->fatsize)) { + debug("curclust: 0x%x\n", curclust); + debug("Invalid FAT entry\n"); + return -1; + } + + actsize += bytesperclust; + endclust = newclust; + } + + /* overwrite to <curclust..endclust> */ + if (pos < cur_pos) + offset = 0; + else + offset = pos - cur_pos; + wsize = min(cur_pos + actsize, filesize) - pos; + if (get_set_cluster(mydata, curclust, offset, + buffer, wsize, &actsize)) { + printf("Error get-and-setting cluster\n"); + return -1; + } + buffer += wsize; + *gotsize += wsize; + cur_pos += offset + wsize; + + if (filesize <= cur_pos) + break; + + /* CHECK: newclust = get_fatent(mydata, endclust); */ + + if (IS_LAST_CLUST(newclust, mydata->fatsize)) + /* no more clusters */ + break; + + curclust = newclust; + } + + if (filesize <= cur_pos) { + /* no more write */ + newclust = get_fatent(mydata, endclust); + if (!IS_LAST_CLUST(newclust, mydata->fatsize)) { + /* truncate the rest */ + clear_fatent(mydata, newclust); + + /* Mark end of file in FAT */ + if (mydata->fatsize == 12) + newclust = 0xfff; + else if (mydata->fatsize == 16) + newclust = 0xffff; + else if (mydata->fatsize == 32) + newclust = 0xfffffff; + set_fatent_value(mydata, endclust, newclust); + } + return 0; } + curclust = endclust; + filesize -= cur_pos; + assert(!(cur_pos % bytesperclust)); + +set_clusters: + /* allocate and write */ + assert(!pos); + + /* Assure that curclust is valid */ + if (!curclust) { + curclust = find_empty_cluster(mydata); + set_start_cluster(mydata, dentptr, curclust); + } else { + newclust = get_fatent(mydata, curclust); + + if (IS_LAST_CLUST(newclust, mydata->fatsize)) { + newclust = determine_fatent(mydata, curclust); + set_fatent_value(mydata, curclust, newclust); + curclust = newclust; + } else { + debug("error: something wrong\n"); + return -1; + } + } + + /* TODO: already partially written */ + if (check_overflow(mydata, curclust, filesize)) { + printf("Error: no space left: %llu\n", filesize); + return -1; + } + actsize = bytesperclust; endclust = curclust; do { @@ -665,6 +858,7 @@ set_contents(fsdata *mydata, dir_entry *dentptr, __u8 *buffer, newclust = determine_fatent(mydata, endclust); if ((newclust - 1) != endclust) + /* write to <curclust..endclust> */ goto getit; if (CHECK_CLUST(newclust, mydata->fatsize)) { @@ -711,18 +905,8 @@ getit: actsize = bytesperclust; curclust = endclust = newclust; } while (1); -} -/* - * Set start cluster in directory entry - */ -static void set_start_cluster(const fsdata *mydata, dir_entry *dentptr, - __u32 start_cluster) -{ - if (mydata->fatsize == 32) - dentptr->starthi = - cpu_to_le16((start_cluster & 0xffff0000) >> 16); - dentptr->start = cpu_to_le16(start_cluster & 0xffff); + return 0; } /* @@ -740,334 +924,512 @@ static void fill_dentry(fsdata *mydata, dir_entry *dentptr, } /* - * Check whether adding a file makes the file system to - * exceed the size of the block device - * Return -1 when overflow occurs, otherwise return 0 + * Find a directory entry based on filename or start cluster number + * If the directory entry is not found, + * the new position for writing a directory entry will be returned */ -static int check_overflow(fsdata *mydata, __u32 clustnum, loff_t size) +static dir_entry *find_directory_entry(fat_itr *itr, char *filename) { - __u32 startsect, sect_num, offset; + int match = 0; - if (clustnum > 0) { - startsect = clust_to_sect(mydata, clustnum); - } else { - startsect = mydata->rootdir_sect; + while (fat_itr_next(itr)) { + /* check both long and short name: */ + if (!strcasecmp(filename, itr->name)) + match = 1; + else if (itr->name != itr->s_name && + !strcasecmp(filename, itr->s_name)) + match = 1; + + if (!match) + continue; + + if (itr->dent->name[0] == '\0') + return NULL; + else + return itr->dent; } - sect_num = div_u64_rem(size, mydata->sect_size, &offset); + if (!itr->dent && !itr->is_root && flush_dir_table(itr)) + /* indicate that allocating dent failed */ + itr->dent = NULL; - if (offset != 0) - sect_num++; + return NULL; +} + +static int split_filename(char *filename, char **dirname, char **basename) +{ + char *p, *last_slash, *last_slash_cont; + +again: + p = filename; + last_slash = NULL; + last_slash_cont = NULL; + while (*p) { + if (ISDIRDELIM(*p)) { + last_slash = p; + last_slash_cont = p; + /* continuous slashes */ + while (ISDIRDELIM(*p)) + last_slash_cont = p++; + if (!*p) + break; + } + p++; + } + + if (last_slash) { + if (last_slash_cont == (filename + strlen(filename) - 1)) { + /* remove trailing slashes */ + *last_slash = '\0'; + goto again; + } + + if (last_slash == filename) { + /* avoid ""(null) directory */ + *dirname = "/"; + } else { + *last_slash = '\0'; + *dirname = filename; + } + + *last_slash_cont = '\0'; + *basename = last_slash_cont + 1; + } else { + *dirname = "/"; /* root by default */ + *basename = filename; + } - if (startsect + sect_num > total_sector) - return -1; return 0; } -/* - * Check if adding several entries exceed one cluster boundary - */ -static int is_next_clust(fsdata *mydata, dir_entry *dentptr) +static int normalize_longname(char *l_filename, const char *filename) { - int cur_position; + const char *p, legal[] = "!#$%&\'()-.@^`_{}~"; + char c; + int name_len; - cur_position = (__u8 *)dentptr - get_dentfromdir_block; + /* Check that the filename is valid */ + for (p = filename; p < filename + strlen(filename); p++) { + c = *p; + + if (('0' <= c) && (c <= '9')) + continue; + if (('A' <= c) && (c <= 'Z')) + continue; + if (('a' <= c) && (c <= 'z')) + continue; + if (strchr(legal, c)) + continue; + /* extended code */ + if ((0x80 <= c) && (c <= 0xff)) + continue; - if (cur_position >= mydata->clust_size * mydata->sect_size) - return 1; - else - return 0; + return -1; + } + + /* Normalize it */ + name_len = strlen(filename); + if (name_len >= VFAT_MAXLEN_BYTES) + /* should return an error? */ + name_len = VFAT_MAXLEN_BYTES - 1; + + memcpy(l_filename, filename, name_len); + l_filename[name_len] = 0; /* terminate the string */ + downcase(l_filename, INT_MAX); + + return 0; } -static dir_entry *empty_dentptr; -/* - * Find a directory entry based on filename or start cluster number - * If the directory entry is not found, - * the new position for writing a directory entry will be returned - */ -static dir_entry *find_directory_entry(fsdata *mydata, int startsect, - char *filename, dir_entry *retdent, __u32 start) +int file_fat_write_at(const char *filename, loff_t pos, void *buffer, + loff_t size, loff_t *actwrite) { - __u32 curclust = sect_to_clust(mydata, startsect); + dir_entry *retdent; + fsdata datablock = { .fatbuf = NULL, }; + fsdata *mydata = &datablock; + fat_itr *itr = NULL; + int ret = -1; + char *filename_copy, *parent, *basename; + char l_filename[VFAT_MAXLEN_BYTES]; - debug("get_dentfromdir: %s\n", filename); + debug("writing %s\n", filename); - while (1) { - dir_entry *dentptr; + filename_copy = strdup(filename); + if (!filename_copy) + return -ENOMEM; - int i; + split_filename(filename_copy, &parent, &basename); + if (!strlen(basename)) { + ret = -EINVAL; + goto exit; + } - if (get_cluster(mydata, curclust, get_dentfromdir_block, - mydata->clust_size * mydata->sect_size) != 0) { - printf("Error: reading directory block\n"); - return NULL; - } + filename = basename; + if (normalize_longname(l_filename, filename)) { + printf("FAT: illegal filename (%s)\n", filename); + ret = -EINVAL; + goto exit; + } - dentptr = (dir_entry *)get_dentfromdir_block; + itr = malloc_cache_aligned(sizeof(fat_itr)); + if (!itr) { + ret = -ENOMEM; + goto exit; + } - dir_curclust = curclust; + ret = fat_itr_root(itr, &datablock); + if (ret) + goto exit; - for (i = 0; i < DIRENTSPERCLUST; i++) { - char s_name[14], l_name[VFAT_MAXLEN_BYTES]; + total_sector = datablock.total_sect; - l_name[0] = '\0'; - if (dentptr->name[0] == DELETED_FLAG) { - dentptr++; - if (is_next_clust(mydata, dentptr)) - break; - continue; - } - if ((dentptr->attr & ATTR_VOLUME)) { - if ((dentptr->attr & ATTR_VFAT) && - (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) { - get_long_file_name(mydata, curclust, - get_dentfromdir_block, - &dentptr, l_name); - debug("vfatname: |%s|\n", l_name); - } else { - /* Volume label or VFAT entry */ - dentptr++; - if (is_next_clust(mydata, dentptr)) - break; - continue; - } - } - if (dentptr->name[0] == 0) { - debug("Dentname == NULL - %d\n", i); - empty_dentptr = dentptr; - return NULL; - } + ret = fat_itr_resolve(itr, parent, TYPE_DIR); + if (ret) { + printf("%s: doesn't exist (%d)\n", parent, ret); + goto exit; + } - get_name(dentptr, s_name); + retdent = find_directory_entry(itr, l_filename); - if (strncasecmp(filename, s_name, sizeof(s_name)) && - strncasecmp(filename, l_name, sizeof(l_name))) { - debug("Mismatch: |%s|%s|\n", - s_name, l_name); - dentptr++; - if (is_next_clust(mydata, dentptr)) - break; - continue; - } + if (retdent) { + if (fat_itr_isdir(itr)) { + ret = -EISDIR; + goto exit; + } - memcpy(retdent, dentptr, sizeof(dir_entry)); + /* A file exists */ + if (pos == -1) + /* Append to the end */ + pos = FAT2CPU32(retdent->size); + if (pos > retdent->size) { + /* No hole allowed */ + ret = -EINVAL; + goto exit; + } - debug("DentName: %s", s_name); - debug(", start: 0x%x", START(dentptr)); - debug(", size: 0x%x %s\n", - FAT2CPU32(dentptr->size), - (dentptr->attr & ATTR_DIR) ? - "(DIR)" : ""); + /* Update file size in a directory entry */ + retdent->size = cpu_to_le32(pos + size); + } else { + /* Create a new file */ - return dentptr; + if (itr->is_root) { + /* root dir cannot have "." or ".." */ + if (!strcmp(l_filename, ".") || + !strcmp(l_filename, "..")) { + ret = -EINVAL; + goto exit; + } } - /* - * In FAT16/12, the root dir is locate before data area, shows - * in following: - * ------------------------------------------------------------- - * | Boot | FAT1 & 2 | Root dir | Data (start from cluster #2) | - * ------------------------------------------------------------- - * - * As a result if curclust is in Root dir, it is a negative - * number or 0, 1. - * - */ - if (mydata->fatsize != 32 && (int)curclust <= 1) { - /* Current clust is in root dir, set to next clust */ - curclust++; - if ((int)curclust <= 1) - continue; /* continue to find */ - - /* Reach the end of root dir */ - empty_dentptr = dentptr; - return NULL; + if (!itr->dent) { + printf("Error: allocating new dir entry\n"); + ret = -EIO; + goto exit; } - curclust = get_fatent(mydata, dir_curclust); - if (IS_LAST_CLUST(curclust, mydata->fatsize)) { - empty_dentptr = dentptr; - return NULL; + if (pos) { + /* No hole allowed */ + ret = -EINVAL; + goto exit; } - if (CHECK_CLUST(curclust, mydata->fatsize)) { - debug("curclust: 0x%x\n", curclust); - debug("Invalid FAT entry\n"); - return NULL; + + memset(itr->dent, 0, sizeof(*itr->dent)); + + /* Set short name to set alias checksum field in dir_slot */ + set_name(itr->dent, filename); + if (fill_dir_slot(itr, filename)) { + ret = -EIO; + goto exit; } + + /* Set attribute as archive for regular file */ + fill_dentry(itr->fsdata, itr->dent, filename, 0, size, 0x20); + + retdent = itr->dent; } - return NULL; + ret = set_contents(mydata, retdent, pos, buffer, size, actwrite); + if (ret < 0) { + printf("Error: writing contents\n"); + ret = -EIO; + goto exit; + } + debug("attempt to write 0x%llx bytes\n", *actwrite); + + /* Flush fat buffer */ + ret = flush_dirty_fat_buffer(mydata); + if (ret) { + printf("Error: flush fat buffer\n"); + ret = -EIO; + goto exit; + } + + /* Write directory table to device */ + ret = set_cluster(mydata, itr->clust, itr->block, + mydata->clust_size * mydata->sect_size); + if (ret) { + printf("Error: writing directory entry\n"); + ret = -EIO; + } + +exit: + free(filename_copy); + free(mydata->fatbuf); + free(itr); + return ret; } -static int do_fat_write(const char *filename, void *buffer, loff_t size, - loff_t *actwrite) +int file_fat_write(const char *filename, void *buffer, loff_t offset, + loff_t maxsize, loff_t *actwrite) { - dir_entry *dentptr, *retdent; - __u32 startsect; - __u32 start_cluster; - boot_sector bs; - volume_info volinfo; - fsdata datablock; - fsdata *mydata = &datablock; - int cursect, i; - int ret = -1, name_len; - char l_filename[VFAT_MAXLEN_BYTES]; - char bad[2] = " "; - const char illegal[] = "<>:\"/\\|?*"; + return file_fat_write_at(filename, offset, buffer, maxsize, actwrite); +} - *actwrite = size; - dir_curclust = 0; +static int fat_dir_entries(fat_itr *itr) +{ + fat_itr *dirs; + fsdata fsdata = { .fatbuf = NULL, }, *mydata = &fsdata; + /* for FATBUFSIZE */ + int count; - if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) { - debug("error: reading boot sector\n"); - return -1; + dirs = malloc_cache_aligned(sizeof(fat_itr)); + if (!dirs) { + debug("Error: allocating memory\n"); + count = -ENOMEM; + goto exit; } - total_sector = bs.total_sect; - if (total_sector == 0) - total_sector = (int)cur_part_info.size; /* cast of lbaint_t */ + /* duplicate fsdata */ + fat_itr_child(dirs, itr); + fsdata = *dirs->fsdata; - if (mydata->fatsize == 32) - mydata->fatlength = bs.fat32_length; - else - mydata->fatlength = bs.fat_length; + /* allocate local fat buffer */ + fsdata.fatbuf = malloc_cache_aligned(FATBUFSIZE); + if (!fsdata.fatbuf) { + debug("Error: allocating memory\n"); + count = -ENOMEM; + goto exit; + } + fsdata.fatbufnum = -1; + dirs->fsdata = &fsdata; - mydata->fat_sect = bs.reserved; + for (count = 0; fat_itr_next(dirs); count++) + ; - cursect = mydata->rootdir_sect - = mydata->fat_sect + mydata->fatlength * bs.fats; - num_of_fats = bs.fats; +exit: + free(fsdata.fatbuf); + free(dirs); + return count; +} - mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0]; - mydata->clust_size = bs.cluster_size; +static int delete_dentry(fat_itr *itr) +{ + fsdata *mydata = itr->fsdata; + dir_entry *dentptr = itr->dent; - if (mydata->fatsize == 32) { - mydata->data_begin = mydata->rootdir_sect - - (mydata->clust_size * 2); - } else { - int rootdir_size; - - rootdir_size = ((bs.dir_entries[1] * (int)256 + - bs.dir_entries[0]) * - sizeof(dir_entry)) / - mydata->sect_size; - mydata->data_begin = mydata->rootdir_sect + - rootdir_size - - (mydata->clust_size * 2); + /* free cluster blocks */ + clear_fatent(mydata, START(dentptr)); + if (flush_dirty_fat_buffer(mydata) < 0) { + printf("Error: flush fat buffer\n"); + return -EIO; } - mydata->fatbufnum = -1; - mydata->fat_dirty = 0; - mydata->fatbuf = memalign(ARCH_DMA_MINALIGN, FATBUFSIZE); - if (mydata->fatbuf == NULL) { - debug("Error: allocating memory\n"); - return -1; + /* + * update a directory entry + * TODO: + * - long file name support + * - find and mark the "new" first invalid entry as name[0]=0x00 + */ + memset(dentptr, 0, sizeof(*dentptr)); + dentptr->name[0] = 0xe5; + + if (set_cluster(mydata, itr->clust, itr->block, + mydata->clust_size * mydata->sect_size) != 0) { + printf("error: writing directory entry\n"); + return -EIO; } - if (disk_read(cursect, - (mydata->fatsize == 32) ? - (mydata->clust_size) : - PREFETCH_BLOCKS, do_fat_read_at_block) < 0) { - debug("Error: reading rootdir block\n"); + return 0; +} + +int fat_unlink(const char *filename) +{ + fsdata fsdata = { .fatbuf = NULL, }; + fat_itr *itr = NULL; + int n_entries, ret; + char *filename_copy, *dirname, *basename; + + filename_copy = strdup(filename); + split_filename(filename_copy, &dirname, &basename); + + if (!strcmp(dirname, "/") && !strcmp(basename, "")) { + printf("Error: cannot remove root\n"); + ret = -EINVAL; goto exit; } - dentptr = (dir_entry *) do_fat_read_at_block; - /* Strip leading (back-)slashes */ - while ISDIRDELIM(*filename) - ++filename; - /* Check that the filename is valid */ - for (i = 0; i < strlen(illegal); ++i) { - *bad = illegal[i]; - if (strstr(filename, bad)) { - printf("FAT: illegal filename (%s)\n", filename); - return -1; + itr = malloc_cache_aligned(sizeof(fat_itr)); + if (!itr) { + printf("Error: allocating memory\n"); + return -ENOMEM; + } + + ret = fat_itr_root(itr, &fsdata); + if (ret) + goto exit; + + total_sector = fsdata.total_sect; + + ret = fat_itr_resolve(itr, dirname, TYPE_DIR); + if (ret) { + printf("%s: doesn't exist (%d)\n", dirname, ret); + ret = -ENOENT; + goto exit; + } + + if (!find_directory_entry(itr, basename)) { + printf("%s: doesn't exist\n", basename); + ret = -ENOENT; + goto exit; + } + + if (fat_itr_isdir(itr)) { + n_entries = fat_dir_entries(itr); + if (n_entries < 0) { + ret = n_entries; + goto exit; + } + if (n_entries > 2) { + printf("Error: directory is not empty: %d\n", + n_entries); + ret = -EINVAL; + goto exit; } } - name_len = strlen(filename); - if (name_len >= VFAT_MAXLEN_BYTES) - name_len = VFAT_MAXLEN_BYTES - 1; + ret = delete_dentry(itr); - memcpy(l_filename, filename, name_len); - l_filename[name_len] = 0; /* terminate the string */ - downcase(l_filename, INT_MAX); +exit: + free(fsdata.fatbuf); + free(itr); + free(filename_copy); - startsect = mydata->rootdir_sect; - retdent = find_directory_entry(mydata, startsect, - l_filename, dentptr, 0); - if (retdent) { - /* Update file size and start_cluster in a directory entry */ - retdent->size = cpu_to_le32(size); - start_cluster = START(retdent); - - if (start_cluster) { - if (size) { - ret = check_overflow(mydata, start_cluster, - size); - if (ret) { - printf("Error: %llu overflow\n", size); - goto exit; - } - } + return ret; +} - ret = clear_fatent(mydata, start_cluster); - if (ret) { - printf("Error: clearing FAT entries\n"); - goto exit; - } +int fat_mkdir(const char *new_dirname) +{ + dir_entry *retdent; + fsdata datablock = { .fatbuf = NULL, }; + fsdata *mydata = &datablock; + fat_itr *itr = NULL; + char *dirname_copy, *parent, *dirname; + char l_dirname[VFAT_MAXLEN_BYTES]; + int ret = -1; + loff_t actwrite; + unsigned int bytesperclust; + dir_entry *dotdent = NULL; + + dirname_copy = strdup(new_dirname); + if (!dirname_copy) + goto exit; - if (!size) - set_start_cluster(mydata, retdent, 0); - } else if (size) { - ret = start_cluster = find_empty_cluster(mydata); - if (ret < 0) { - printf("Error: finding empty cluster\n"); - goto exit; - } + split_filename(dirname_copy, &parent, &dirname); + if (!strlen(dirname)) { + ret = -EINVAL; + goto exit; + } - ret = check_overflow(mydata, start_cluster, size); - if (ret) { - printf("Error: %llu overflow\n", size); - goto exit; - } + if (normalize_longname(l_dirname, dirname)) { + printf("FAT: illegal filename (%s)\n", dirname); + ret = -EINVAL; + goto exit; + } - set_start_cluster(mydata, retdent, start_cluster); - } - } else { - /* Set short name to set alias checksum field in dir_slot */ - set_name(empty_dentptr, filename); - fill_dir_slot(mydata, &empty_dentptr, filename); + itr = malloc_cache_aligned(sizeof(fat_itr)); + if (!itr) { + ret = -ENOMEM; + goto exit; + } - if (size) { - ret = start_cluster = find_empty_cluster(mydata); - if (ret < 0) { - printf("Error: finding empty cluster\n"); - goto exit; - } + ret = fat_itr_root(itr, &datablock); + if (ret) + goto exit; + + total_sector = datablock.total_sect; + + ret = fat_itr_resolve(itr, parent, TYPE_DIR); + if (ret) { + printf("%s: doesn't exist (%d)\n", parent, ret); + goto exit; + } + + retdent = find_directory_entry(itr, l_dirname); - ret = check_overflow(mydata, start_cluster, size); - if (ret) { - printf("Error: %llu overflow\n", size); + if (retdent) { + printf("%s: already exists\n", l_dirname); + ret = -EEXIST; + goto exit; + } else { + if (itr->is_root) { + /* root dir cannot have "." or ".." */ + if (!strcmp(l_dirname, ".") || + !strcmp(l_dirname, "..")) { + ret = -EINVAL; goto exit; } - } else { - start_cluster = 0; } - /* Set attribute as archieve for regular file */ - fill_dentry(mydata, empty_dentptr, filename, - start_cluster, size, 0x20); + if (!itr->dent) { + printf("Error: allocating new dir entry\n"); + ret = -EIO; + goto exit; + } + + memset(itr->dent, 0, sizeof(*itr->dent)); + + /* Set short name to set alias checksum field in dir_slot */ + set_name(itr->dent, dirname); + fill_dir_slot(itr, dirname); + + /* Set attribute as archive for regular file */ + fill_dentry(itr->fsdata, itr->dent, dirname, 0, 0, + ATTR_DIR | ATTR_ARCH); - retdent = empty_dentptr; + retdent = itr->dent; } - ret = set_contents(mydata, retdent, buffer, size, actwrite); + /* Default entries */ + bytesperclust = mydata->clust_size * mydata->sect_size; + dotdent = malloc_cache_aligned(bytesperclust); + if (!dotdent) { + ret = -ENOMEM; + goto exit; + } + memset(dotdent, 0, bytesperclust); + + memcpy(dotdent[0].name, ". ", 8); + memcpy(dotdent[0].ext, " ", 3); + dotdent[0].attr = ATTR_DIR | ATTR_ARCH; + + memcpy(dotdent[1].name, ".. ", 8); + memcpy(dotdent[1].ext, " ", 3); + dotdent[1].attr = ATTR_DIR | ATTR_ARCH; + set_start_cluster(mydata, &dotdent[1], itr->start_clust); + + ret = set_contents(mydata, retdent, 0, (__u8 *)dotdent, + bytesperclust, &actwrite); + if (ret < 0) { + printf("Error: writing contents\n"); + goto exit; + } + /* Write twice for "." */ + set_start_cluster(mydata, &dotdent[0], START(retdent)); + ret = set_contents(mydata, retdent, 0, (__u8 *)dotdent, + bytesperclust, &actwrite); if (ret < 0) { printf("Error: writing contents\n"); goto exit; } - debug("attempt to write 0x%llx bytes\n", *actwrite); /* Flush fat buffer */ ret = flush_dirty_fat_buffer(mydata); @@ -1077,24 +1439,15 @@ static int do_fat_write(const char *filename, void *buffer, loff_t size, } /* Write directory table to device */ - ret = set_cluster(mydata, dir_curclust, get_dentfromdir_block, - mydata->clust_size * mydata->sect_size); + ret = set_cluster(mydata, itr->clust, itr->block, + mydata->clust_size * mydata->sect_size); if (ret) printf("Error: writing directory entry\n"); exit: + free(dirname_copy); free(mydata->fatbuf); + free(itr); + free(dotdent); return ret; } - -int file_fat_write(const char *filename, void *buffer, loff_t offset, - loff_t maxsize, loff_t *actwrite) -{ - if (offset != 0) { - printf("Error: non zero offset is currently not supported.\n"); - return -1; - } - - printf("writing %s\n", filename); - return do_fat_write(filename, buffer, maxsize, actwrite); -} |