diff options
Diffstat (limited to 'fs/fat/fat.c')
-rw-r--r-- | fs/fat/fat.c | 172 |
1 files changed, 91 insertions, 81 deletions
diff --git a/fs/fat/fat.c b/fs/fat/fat.c index bc46cc5d20..19f6a8c0af 100644 --- a/fs/fat/fat.c +++ b/fs/fat/fat.c @@ -37,7 +37,7 @@ /* * Convert a string to lowercase. */ -static void downcase (char *str) +static void downcase(char *str) { while (*str != '\0') { TOLOWER(*str); @@ -62,7 +62,7 @@ static int disk_read(__u32 block, __u32 nr_blocks, void *buf) cur_part_info.start + block, nr_blocks, buf); } -int fat_register_device (block_dev_desc_t * dev_desc, int part_no) +int fat_register_device(block_dev_desc_t * dev_desc, int part_no) { ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz); @@ -127,7 +127,7 @@ int fat_register_device (block_dev_desc_t * dev_desc, int part_no) * Get the first occurence of a directory delimiter ('/' or '\') in a string. * Return index into string if found, -1 otherwise. */ -static int dirdelim (char *str) +static int dirdelim(char *str) { char *start = str; @@ -142,7 +142,7 @@ static int dirdelim (char *str) /* * Extract zero terminated short name from a directory entry. */ -static void get_name (dir_entry *dirent, char *s_name) +static void get_name(dir_entry *dirent, char *s_name) { char *ptr; @@ -171,7 +171,7 @@ static void get_name (dir_entry *dirent, char *s_name) * Get the entry at index 'entry' in a FAT (12/16/32) table. * On failure 0x00 is returned. */ -static __u32 get_fatent (fsdata *mydata, __u32 entry) +static __u32 get_fatent(fsdata *mydata, __u32 entry) { __u32 bufnum; __u32 off16, offset; @@ -207,10 +207,9 @@ static __u32 get_fatent (fsdata *mydata, __u32 entry) __u32 fatlength = mydata->fatlength; __u32 startblock = bufnum * FATBUFBLOCKS; - if (getsize > fatlength) - getsize = fatlength; + if (startblock + getsize > fatlength) + getsize = fatlength - startblock; - fatlength *= mydata->sect_size; /* We want it in bytes now */ startblock += mydata->fat_sect; /* Offset from start of disk */ if (disk_read(startblock, getsize, bufptr) < 0) { @@ -270,12 +269,10 @@ static __u32 get_fatent (fsdata *mydata, __u32 entry) * Return 0 on success, -1 otherwise. */ static int -get_cluster (fsdata *mydata, __u32 clustnum, __u8 *buffer, - unsigned long size) +get_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size) { __u32 idx = 0; __u32 startsect; - __u32 nr_sect; int ret; if (clustnum > 0) { @@ -287,25 +284,44 @@ get_cluster (fsdata *mydata, __u32 clustnum, __u8 *buffer, debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect); - nr_sect = size / mydata->sect_size; - ret = disk_read(startsect, nr_sect, buffer); - if (ret != nr_sect) { - debug("Error reading data (got %d)\n", ret); - return -1; - } - if (size % mydata->sect_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); + + while (size >= mydata->sect_size) { + ret = disk_read(startsect++, 1, tmpbuf); + if (ret != 1) { + debug("Error reading data (got %d)\n", ret); + return -1; + } + + memcpy(buffer, tmpbuf, mydata->sect_size); + buffer += mydata->sect_size; + size -= mydata->sect_size; + } + } else { idx = size / mydata->sect_size; - ret = disk_read(startsect + idx, 1, tmpbuf); + ret = disk_read(startsect, idx, buffer); + if (ret != idx) { + debug("Error reading data (got %d)\n", ret); + return -1; + } + startsect += idx; + idx *= mydata->sect_size; + buffer += idx; + size -= idx; + } + if (size) { + ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size); + + ret = disk_read(startsect, 1, tmpbuf); if (ret != 1) { debug("Error reading data (got %d)\n", ret); return -1; } - buffer += idx * mydata->sect_size; - memcpy(buffer, tmpbuf, size % mydata->sect_size); - return 0; + memcpy(buffer, tmpbuf, size); } return 0; @@ -317,8 +333,8 @@ get_cluster (fsdata *mydata, __u32 clustnum, __u8 *buffer, * Return the number of bytes read or -1 on fatal errors. */ static long -get_contents (fsdata *mydata, dir_entry *dentptr, __u8 *buffer, - unsigned long maxsize) +get_contents(fsdata *mydata, dir_entry *dentptr, __u8 *buffer, + unsigned long maxsize) { unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0; unsigned int bytesperclust = mydata->clust_size * mydata->sect_size; @@ -351,21 +367,9 @@ get_contents (fsdata *mydata, dir_entry *dentptr, __u8 *buffer, actsize += bytesperclust; } - /* actsize >= file size */ - actsize -= bytesperclust; - - /* get remaining clusters */ - if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) { - printf("Error reading cluster\n"); - return -1; - } - /* get remaining bytes */ - gotsize += (int)actsize; - filesize -= actsize; - buffer += actsize; actsize = filesize; - if (get_cluster(mydata, endclust, buffer, (int)actsize) != 0) { + if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) { printf("Error reading cluster\n"); return -1; } @@ -397,7 +401,7 @@ getit: * starting at l_name[*idx]. * Return 1 if terminator (zero byte) is found, 0 otherwise. */ -static int slot2str (dir_slot *slotptr, char *l_name, int *idx) +static int slot2str(dir_slot *slotptr, char *l_name, int *idx) { int j; @@ -433,8 +437,8 @@ __u8 get_vfatname_block[MAX_CLUSTSIZE] __aligned(ARCH_DMA_MINALIGN); static int -get_vfatname (fsdata *mydata, int curclust, __u8 *cluster, - dir_entry *retdent, char *l_name) +get_vfatname(fsdata *mydata, int curclust, __u8 *cluster, + dir_entry *retdent, char *l_name) { dir_entry *realdent; dir_slot *slotptr = (dir_slot *)retdent; @@ -516,7 +520,7 @@ get_vfatname (fsdata *mydata, int curclust, __u8 *cluster, } /* Calculate short name checksum */ -static __u8 mkcksum (const char *str) +static __u8 mkcksum(const char *str) { int i; @@ -537,9 +541,9 @@ static __u8 mkcksum (const char *str) __u8 get_dentfromdir_block[MAX_CLUSTSIZE] __aligned(ARCH_DMA_MINALIGN); -static dir_entry *get_dentfromdir (fsdata *mydata, int startsect, - char *filename, dir_entry *retdent, - int dols) +static dir_entry *get_dentfromdir(fsdata *mydata, int startsect, + char *filename, dir_entry *retdent, + int dols) { __u16 prevcksum = 0xffff; __u32 curclust = START(retdent); @@ -699,7 +703,7 @@ static dir_entry *get_dentfromdir (fsdata *mydata, int startsect, * Read boot sector and volume info from a FAT filesystem */ static int -read_bootsectandvi (boot_sector *bs, volume_info *volinfo, int *fatsize) +read_bootsectandvi(boot_sector *bs, volume_info *volinfo, int *fatsize) { __u8 *block; volume_info *vistart; @@ -716,7 +720,7 @@ read_bootsectandvi (boot_sector *bs, volume_info *volinfo, int *fatsize) return -1; } - if (disk_read (0, 1, block) < 0) { + if (disk_read(0, 1, block) < 0) { debug("Error: reading block\n"); goto fail; } @@ -770,15 +774,14 @@ __u8 do_fat_read_block[MAX_CLUSTSIZE] __aligned(ARCH_DMA_MINALIGN); long -do_fat_read (const char *filename, void *buffer, unsigned long maxsize, - int dols) +do_fat_read(const char *filename, void *buffer, unsigned long maxsize, int dols) { char fnamecopy[2048]; boot_sector bs; volume_info volinfo; fsdata datablock; fsdata *mydata = &datablock; - dir_entry *dentptr; + dir_entry *dentptr = NULL; __u16 prevcksum = 0xffff; char *subname = ""; __u32 cursect; @@ -877,19 +880,21 @@ do_fat_read (const char *filename, void *buffer, unsigned long maxsize, while (1) { int i; - debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%zd\n", - cursect, mydata->clust_size, DIRENTSPERBLOCK); + if (j == 0) { + debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%zd\n", + cursect, mydata->clust_size, DIRENTSPERBLOCK); - if (disk_read(cursect, - (mydata->fatsize == 32) ? - (mydata->clust_size) : - PREFETCH_BLOCKS, - do_fat_read_block) < 0) { - debug("Error: reading rootdir block\n"); - goto exit; - } + if (disk_read(cursect, + (mydata->fatsize == 32) ? + (mydata->clust_size) : + PREFETCH_BLOCKS, + do_fat_read_block) < 0) { + debug("Error: reading rootdir block\n"); + goto exit; + } - dentptr = (dir_entry *) do_fat_read_block; + dentptr = (dir_entry *) do_fat_read_block; + } for (i = 0; i < DIRENTSPERBLOCK; i++) { char s_name[14], l_name[VFAT_MAXLEN_BYTES]; @@ -1031,28 +1036,33 @@ do_fat_read (const char *filename, void *buffer, unsigned long maxsize, * completely processed. */ ++j; - int fat32_end = 0; - if ((mydata->fatsize == 32) && (j == mydata->clust_size)) { - int nxtsect = 0; - int nxt_clust = 0; + int rootdir_end = 0; + if (mydata->fatsize == 32) { + if (j == mydata->clust_size) { + int nxtsect = 0; + int nxt_clust = 0; - nxt_clust = get_fatent(mydata, root_cluster); - fat32_end = CHECK_CLUST(nxt_clust, 32); + nxt_clust = get_fatent(mydata, root_cluster); + rootdir_end = CHECK_CLUST(nxt_clust, 32); - nxtsect = mydata->data_begin + - (nxt_clust * mydata->clust_size); + nxtsect = mydata->data_begin + + (nxt_clust * mydata->clust_size); - root_cluster = nxt_clust; + root_cluster = nxt_clust; - cursect = nxtsect; - j = 0; + cursect = nxtsect; + j = 0; + } } else { - cursect++; + if (j == PREFETCH_BLOCKS) + j = 0; + + rootdir_end = (++cursect - mydata->rootdir_sect >= + rootdir_size); } /* If end of rootdir reached */ - if ((mydata->fatsize == 32 && fat32_end) || - (mydata->fatsize != 32 && j == rootdir_size)) { + if (rootdir_end) { if (dols == LS_ROOT) { printf("\n%d file(s), %d dir(s)\n\n", files, dirs); @@ -1099,11 +1109,11 @@ rootdir_done: goto exit; } - if (idx >= 0) { - if (!(dentptr->attr & ATTR_DIR)) - goto exit; + if (isdir && !(dentptr->attr & ATTR_DIR)) + goto exit; + + if (idx >= 0) subname = nextname; - } } ret = get_contents(mydata, dentptr, buffer, maxsize); @@ -1114,7 +1124,7 @@ exit: return ret; } -int file_fat_detectfs (void) +int file_fat_detectfs(void) { boot_sector bs; volume_info volinfo; @@ -1177,12 +1187,12 @@ int file_fat_detectfs (void) return 0; } -int file_fat_ls (const char *dir) +int file_fat_ls(const char *dir) { return do_fat_read(dir, NULL, 0, LS_YES); } -long file_fat_read (const char *filename, void *buffer, unsigned long maxsize) +long file_fat_read(const char *filename, void *buffer, unsigned long maxsize) { printf("reading %s\n", filename); return do_fat_read(filename, buffer, maxsize, LS_NO); |