FIX: fat: Provide correct return code from disk_{read|write} to upper layers

It is very common that FAT code is using following pattern:
if (disk_{read|write}() < 0)
        return -1;

Up till now the above code was dead, since disk_{read|write) could only
return value >= 0.
As a result some errors from medium layer (i.e. eMMC/SD) were not caught.

The above behavior was caused by block_{read|write|erase} declared at
struct block_dev_desc (@part.h). It returns unsigned long, where 0
indicates error and > 0 indicates that medium operation was correct.

This patch as error regards 0 returned from block_{read|write|erase}
when nr_blocks is grater than zero. Read/Write operation with nr_blocks=0
should return 0 and hence is not considered as an error.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>

Test HW: Odroid XU3 - Exynos 5433
This commit is contained in:
Łukasz Majewski 2015-09-03 14:21:39 +02:00 committed by Tom Rini
parent bcd62e72b2
commit 0a04ed86cf
2 changed files with 18 additions and 4 deletions

View file

@ -46,11 +46,18 @@ static disk_partition_t cur_part_info;
static int disk_read(__u32 block, __u32 nr_blocks, void *buf) static int disk_read(__u32 block, __u32 nr_blocks, void *buf)
{ {
ulong ret;
if (!cur_dev || !cur_dev->block_read) if (!cur_dev || !cur_dev->block_read)
return -1; return -1;
return cur_dev->block_read(cur_dev->dev, ret = cur_dev->block_read(cur_dev->dev,
cur_part_info.start + block, nr_blocks, buf); cur_part_info.start + block, nr_blocks, buf);
if (nr_blocks && ret == 0)
return -1;
return ret;
} }
int fat_set_blk_dev(block_dev_desc_t *dev_desc, disk_partition_t *info) int fat_set_blk_dev(block_dev_desc_t *dev_desc, disk_partition_t *info)

View file

@ -30,6 +30,8 @@ static void uppercase(char *str, int len)
static int total_sector; static int total_sector;
static int disk_write(__u32 block, __u32 nr_blocks, void *buf) static int disk_write(__u32 block, __u32 nr_blocks, void *buf)
{ {
ulong ret;
if (!cur_dev || !cur_dev->block_write) if (!cur_dev || !cur_dev->block_write)
return -1; return -1;
@ -39,8 +41,13 @@ static int disk_write(__u32 block, __u32 nr_blocks, void *buf)
return -1; return -1;
} }
return cur_dev->block_write(cur_dev->dev, ret = cur_dev->block_write(cur_dev->dev,
cur_part_info.start + block, nr_blocks, buf); cur_part_info.start + block,
nr_blocks, buf);
if (nr_blocks && ret == 0)
return -1;
return ret;
} }
/* /*