Do FAT read and write based on the device sector size instead of the size recorded in the FAT meta data. This helps to overcome the 'FAT sector size mismatch' error and enables U-Boot to read/write those partitions.
Signed-off-by: Varadarajan Narayanan quic_varada@quicinc.com --- fs/fat/fat.c | 227 ++++++++++++++++++++++++++++++++++++++++++--- fs/fat/fat_write.c | 19 ---- 2 files changed, 214 insertions(+), 32 deletions(-)
diff --git a/fs/fat/fat.c b/fs/fat/fat.c index e2570e8167..f4bad99335 100644 --- a/fs/fat/fat.c +++ b/fs/fat/fat.c @@ -44,24 +44,223 @@ static void downcase(char *str, size_t len)
static struct blk_desc *cur_dev; static struct disk_partition cur_part_info; +int fat_sect_size;
#define DOS_BOOT_MAGIC_OFFSET 0x1fe #define DOS_FS_TYPE_OFFSET 0x36 #define DOS_FS32_TYPE_OFFSET 0x52
-static int disk_read(__u32 block, __u32 nr_blocks, void *buf) +inline __u32 sect_to_block(__u32 sect, __u32 *off) { - ulong ret; + *off = 0; + if (fat_sect_size && fat_sect_size < cur_part_info.blksz) { + int div = cur_part_info.blksz / fat_sect_size; + + *off = sect % div; + return sect / div; + } else if (fat_sect_size && (fat_sect_size > cur_part_info.blksz)) { + return sect * (fat_sect_size / cur_part_info.blksz); + }
- if (!cur_dev) - return -1; + return sect; +}
- ret = blk_dread(cur_dev, cur_part_info.start + block, nr_blocks, buf); +inline __u32 size_to_blocks(__u32 size) +{ + return (size + (cur_part_info.blksz - 1)) / cur_part_info.blksz; +}
- if (ret != nr_blocks) - return -1; +static int disk_read(__u32 sect, __u32 nr_sect, void *buf) +{ + int ret; + __u8 *block = NULL; + __u32 rem, size; + __u32 s, n;
- return ret; + rem = nr_sect * fat_sect_size; + /* + * block N block N + 1 block N + 2 + * +-+-+--+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | | | | |s|e|c|t|o|r| | |s|e|c|t|o|r| | |s|e|c|t|o|r| | | | | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * . . . | | | | . . . + * ------+---------------+---------------+---------------+------ + * |<--- FAT reads in sectors --->| + * + * | part 1 | part 2 | part 3 | + * + */ + + /* Do part 1 */ + if (fat_sect_size) { + __u32 offset; + + /* Read one block and copy out the leading sectors */ + block = malloc_cache_aligned(cur_dev->blksz); + if (!block) { + printf("Error: allocating block: %lu\n", cur_dev->blksz); + return -1; + } + + s = sect_to_block(sect, &offset); + offset = offset * fat_sect_size; + + ret = blk_dread(cur_dev, cur_part_info.start + s, 1, block); + if (ret != 1) { + ret = -1; + goto exit; + } + + if (rem > (cur_part_info.blksz - offset)) + size = cur_part_info.blksz - offset; + else + size = rem; + + memcpy(buf, block + offset, size); + rem -= size; + buf += size; + s++; + } else { + /* + * fat_sect_size not being set implies, this is the first read + * to partition. The first sector is being read to get the + * FS meta data. The FAT sector size is got from this meta data. + */ + ret = blk_dread(cur_dev, cur_part_info.start + s, 1, buf); + if (ret != 1) + return -1; + } + + /* Do part 2, read directly into the given buffer */ + if (rem > cur_part_info.blksz) { + n = rem / cur_part_info.blksz; + ret = blk_dread(cur_dev, cur_part_info.start + s, n, buf); + if (ret != n) { + ret = -1; + goto exit; + } + buf += n * cur_part_info.blksz; + rem = rem % cur_part_info.blksz; + s += n; + } + + /* Do part 3, read a block and copy the trailing sectors */ + if (rem) { + ret = blk_dread(cur_dev, cur_part_info.start + s, 1, block); + if (ret != 1) { + ret = -1; + goto exit; + } else { + memcpy(buf, block, rem); + } + } +exit: + if (block) + free(block); + + return (ret == -1) ? -1 : nr_sect; +} + +int disk_write(__u32 sect, __u32 nr_sect, void *buf) +{ + int ret; + __u8 *block = NULL; + __u32 rem, size; + __u32 s, n; + + rem = nr_sect * fat_sect_size; + /* + * block N block N + 1 block N + 2 + * +-+-+--+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | | | | |s|e|c|t|o|r| | |s|e|c|t|o|r| | |s|e|c|t|o|r| | | | | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * . . . | | | | . . . + * ------+---------------+---------------+---------------+------ + * |<--- FAT reads in sectors --->| + * + * | part 1 | part 2 | part 3 | + * + */ + + /* Do part 1 */ + if (fat_sect_size) { + __u32 offset; + + /* Read one block and overwrite the leading sectors */ + block = malloc_cache_aligned(cur_dev->blksz); + if (!block) { + printf("Error: allocating block: %lu\n", cur_dev->blksz); + return -1; + } + + s = sect_to_block(sect, &offset); + offset = offset * fat_sect_size; + + ret = blk_dread(cur_dev, cur_part_info.start + s, 1, block); + if (ret != 1) { + ret = -1; + goto exit; + } + + if (rem > (cur_part_info.blksz - offset)) + size = cur_part_info.blksz - offset; + else + size = rem; + + memcpy(block + offset, buf, size); + ret = blk_dwrite(cur_dev, cur_part_info.start + s, 1, block); + if (ret != 1) { + ret = -1; + goto exit; + } + + rem -= size; + buf += size; + s++; + } else { + /* + * fat_sect_size not being set implies, this is the first read + * to partition. The first sector is being read to get the + * FS meta data. The FAT sector size is got from this meta data. + */ + ret = blk_dread(cur_dev, cur_part_info.start + s, 1, buf); + if (ret != 1) + return -1; + } + + /* Do part 2, write directly from the given buffer */ + if (rem > cur_part_info.blksz) { + n = rem / cur_part_info.blksz; + ret = blk_dwrite(cur_dev, cur_part_info.start + s, n, buf); + if (ret != n) { + ret = -1; + goto exit; + } + buf += n * cur_part_info.blksz; + rem = rem % cur_part_info.blksz; + s += n; + } + + /* Do part 3, read a block and copy the trailing sectors */ + if (rem) { + ret = blk_dread(cur_dev, cur_part_info.start + s, 1, block); + if (ret != 1) { + ret = -1; + goto exit; + } else { + memcpy(block, buf, rem); + } + ret = blk_dwrite(cur_dev, cur_part_info.start + s, 1, block); + if (ret != 1) { + ret = -1; + goto exit; + } + } +exit: + if (block) + free(block); + + return (ret == -1) ? -1 : nr_sect; }
int fat_set_blk_dev(struct blk_desc *dev_desc, struct disk_partition *info) @@ -575,6 +774,8 @@ read_bootsectandvi(boot_sector *bs, volume_info *volinfo, int *fatsize) return -1; }
+ fat_sect_size = 0; + if (disk_read(0, 1, block) < 0) { debug("Error: reading block\n"); ret = -1; @@ -645,12 +846,12 @@ static int get_fs_info(fsdata *mydata) mydata->rootdir_sect = mydata->fat_sect + mydata->fatlength * bs.fats;
mydata->sect_size = get_unaligned_le16(bs.sector_size); + fat_sect_size = mydata->sect_size; mydata->clust_size = bs.cluster_size; - if (mydata->sect_size != cur_part_info.blksz) { - log_err("FAT sector size mismatch (fs=%u, dev=%lu)\n", - mydata->sect_size, cur_part_info.blksz); - return -1; - } + if (mydata->sect_size != cur_part_info.blksz) + log_info("FAT sector size mismatch (fs=%u, dev=%lu)\n", + mydata->sect_size, cur_part_info.blksz); + if (mydata->clust_size == 0) { log_err("FAT cluster size not set\n"); return -1; diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c index ea877ee917..f7a210d790 100644 --- a/fs/fat/fat_write.c +++ b/fs/fat/fat_write.c @@ -192,25 +192,6 @@ out: }
static int total_sector; -static int disk_write(__u32 block, __u32 nr_blocks, void *buf) -{ - ulong ret; - - if (!cur_dev) - return -1; - - if (cur_part_info.start + block + nr_blocks > - cur_part_info.start + total_sector) { - printf("error: overflow occurs\n"); - return -1; - } - - ret = blk_dwrite(cur_dev, cur_part_info.start + block, nr_blocks, buf); - if (nr_blocks && ret == 0) - return -1; - - return ret; -}
/* * Write fat buffer into block device