From: Stephen Warren swarren@nvidia.com
Logically, a disk that contains a raw FAT filesystem does not in fact have a partition table. However, test_part_dos() was claiming that such disks did in fact have a DOS-style partition table. This caused get_device_and_partition() not to return a whole-disk disk_partition_t, since part_type != PART_TYPE_UNKNOWN.
part_dos.c's print_partition_extended() detected the raw FAT filesystem condition and printed a fake partition table that encompassed the whole disk.
However, part_dos.c's get_partition_info_extended() did not return any valid partitions in this case. This combination caused get_device_and_partition() not to find any valid partitions, and hence to return an error.
Fix test_part_dos() not to claim that raw FAT filesystems are DOS partition tables. In turn, this causes get_device_and_partition() to return a whole-disk disk_partition_t, and hence the following commands work:
fatls mmc 0 / fatls mmc 0:auto /
An alternative would be to modify print_partition_extended() to detect raw FAT filesystems, just like print_partition_extended() does, and to return a fake partition in this case. However, this seems logically incorrect, and also duplicates code, since get_device_and_partition() falls back to returning a whole-disk partition when there is no partition table on the device.
Signed-off-by: Stephen Warren swarren@nvidia.com --- disk/part_dos.c | 21 +++++++++------------ 1 files changed, 9 insertions(+), 12 deletions(-)
diff --git a/disk/part_dos.c b/disk/part_dos.c index c9a3e2b..5c454e6 100644 --- a/disk/part_dos.c +++ b/disk/part_dos.c @@ -94,12 +94,13 @@ int test_part_dos (block_dev_desc_t *dev_desc) { ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz);
- if ((dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *) buffer) != 1) || - (buffer[DOS_PART_MAGIC_OFFSET + 0] != 0x55) || - (buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) ) { - return (-1); - } - return (0); + if (dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *) buffer) != 1) + return -1; + + if (test_block_type(buffer) != DOS_MBR) + return -1; + + return 0; }
/* Print a partition that is relative to its Extended partition table @@ -117,17 +118,13 @@ static void print_partition_extended (block_dev_desc_t *dev_desc, int ext_part_s return; } i=test_block_type(buffer); - if(i==-1) { + if (i != DOS_MBR) { printf ("bad MBR sector signature 0x%02x%02x\n", buffer[DOS_PART_MAGIC_OFFSET], buffer[DOS_PART_MAGIC_OFFSET + 1]); return; } - if(i==DOS_PBR) { - printf (" 1\t\t 0\t%10ld\t%2x\n", - dev_desc->lba, buffer[DOS_PBR_MEDIA_TYPE_OFFSET]); - return; - } + /* Print all primary/logical partitions */ pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET); for (i = 0; i < 4; i++, pt++) {