Re: [PATCH] Fix pointer cast for 32 bits arch

[Peter Senna Tschudin]

On Mon, Apr 13, 2015 at 11:10 AM, Dan Carpenter
<dan.carpenter@xxxxxxxxxx> wrote:
> On Sun, Apr 12, 2015 at 11:26:43AM +0200, Peter Senna Tschudin wrote:
>> Sparse compalins about casting void * to u64 on i386.
>> Change the cast to resource_size_t.
>>
>> Signed-off-by: Peter Senna Tschudin <peter.senna@xxxxxxxxx>
>> ---
>>
>> Tested by compilation only. Tested for x86 and x86_64.
>>
>>  drivers/staging/goldfish/goldfish_nand.c | 3 ++-
>>  include/linux/goldfish.h                 | 2 +-
>>  2 files changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/staging/goldfish/goldfish_nand.c b/drivers/staging/goldfish/goldfish_nand.c
>> index d68f216..738fdc4 100644
>> --- a/drivers/staging/goldfish/goldfish_nand.c
>> +++ b/drivers/staging/goldfish/goldfish_nand.c
>> @@ -87,7 +87,8 @@ static u32 goldfish_nand_cmd(struct mtd_info *mtd, enum nand_cmd cmd,
>>               writel((u32)(addr >> 32), base + NAND_ADDR_HIGH);
>>               writel((u32)addr, base + NAND_ADDR_LOW);
>>               writel(len, base + NAND_TRANSFER_SIZE);
>> -             gf_write64((u64)ptr, base + NAND_DATA, base + NAND_DATA_HIGH);
>> +             gf_write64((resource_size_t)ptr, base + NAND_DATA,
>> +                        base + NAND_DATA_HIGH);
>
> write64 is a misleading name because it only writes 32 bits on 32 bit
> systems.
>
> Are you sure it's a resource_size_t?  If that's really true then this
> code needs a lot more work.  The ifdef in gf_write64() should be
> CONFIG_PHYS_ADDR_T_64BIT and ops->datbuf needs to updated.  It would be
> a lot of changes...
>
> I *think* but I'm not positive that gf_write64 should just take a void
> pointer like this:
>
> diff --git a/drivers/staging/goldfish/goldfish_nand.c b/drivers/staging/goldfish/goldfish_nand.c
> index 213877a..92d6479 100644
> --- a/drivers/staging/goldfish/goldfish_nand.c
> +++ b/drivers/staging/goldfish/goldfish_nand.c
> @@ -87,7 +87,7 @@ static u32 goldfish_nand_cmd(struct mtd_info *mtd, enum nand_cmd cmd,
>                 writel((u32)(addr >> 32), base + NAND_ADDR_HIGH);
>                 writel((u32)addr, base + NAND_ADDR_LOW);
>                 writel(len, base + NAND_TRANSFER_SIZE);
> -               gf_write64((u64)ptr, base + NAND_DATA, base + NAND_DATA_HIGH);
> +               gf_write64(ptr, base + NAND_DATA, base + NAND_DATA_HIGH);
>                 writel(cmd, base + NAND_COMMAND);
>                 rv = readl(base + NAND_RESULT);
>         }
> diff --git a/include/linux/goldfish.h b/include/linux/goldfish.h
> index 569236e..4cdb913 100644
> --- a/include/linux/goldfish.h
> +++ b/include/linux/goldfish.h
> @@ -3,12 +3,12 @@
>
>  /* Helpers for Goldfish virtual platform */
>
> -static inline void gf_write64(unsigned long data,
> +static inline void gf_write64(void *data,
>                 void __iomem *portl, void __iomem *porth)
>  {
> -       writel((u32)data, portl);
> +       writel((u32)(unsigned long)data, portl);
>  #ifdef CONFIG_64BIT
> -       writel(data>>32, porth);
> +       writel((unsigned long)data >> 32, porth);
>  #endif
>  }
>

I like this solution. Should I send a single patch changing
gf_write64() and removing all casts when calling the gf_write64(), or
if to split, how to split the patch?



-- 
Peter
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