[PATCH v4 1/9] mtd: nand: add oob iterator in nand_for_each_page

[Peter Pan]

Hi Boris,

On Thu, Mar 30, 2017 at 3:34 AM, Boris Brezillon
<boris.brezillon at free-electrons.com> wrote:
> On Thu, 23 Mar 2017 17:43:38 +0800
> Peter Pan <peterpandong at micron.com> wrote:
>
>> Iterate nand pages by both page and oob operation.
>
> For the next version, can you merge my initial commit [1] into this one
> (you can keep the authorship)?

OK. I will merge it. But I'd like to keep you as author since it's your idea:)

>
>>
>> Signed-off-by: Peter Pan <peterpandong at micron.com>
>> ---
>>  include/linux/mtd/nand.h | 38 +++++++++++++++++++++++++++++++-------
>>  1 file changed, 31 insertions(+), 7 deletions(-)
>>
>> diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
>> index c2197b4..54ded4c 100644
>> --- a/include/linux/mtd/nand.h
>> +++ b/include/linux/mtd/nand.h
>> @@ -84,9 +84,12 @@ struct nand_device {
>>   * @pageoffset: the offset within a page
>
> Update the documentation.

Fix this in v5

>
>>   */
>>  struct nand_page_iter {
>> -     loff_t offs;
>>       int page;
>>       int pageoffs;
>> +     size_t dataleft;
>> +     int ooboffs;
>> +     int oobsize;
>
> oobsize can be extracted from nand_device, and since a nand_device
> object it passed to all nand_page_iter_xxx() functions you don't need it
> here.

Er.. I think we can not get oobsize from nand_device, since oobsize is
determined
by mtd_oob_ops.mode, it can be mtd->oobavail or mtd->oobsize. What do
you think Boris?

>
>> +     size_t oobleft;
>>  };
>>
>>  /**
>> @@ -193,14 +196,19 @@ static inline int nand_per_page_oobsize(struct nand_device *nand)
>>   * @offs: absolute offset
>>   * @iter: page iterator
>
> Update the documentation.

Fix this in v5

>
>>   */
>> -static inline void nand_page_iter_init(struct nand_device *nand, loff_t offs,
>> +static inline void nand_page_iter_init(struct nand_device *nand,
>> +                                    loff_t offs, size_t len, u32 ooboffs,
>> +                                    size_t ooblen, u32 oobsize,
>>                                      struct nand_page_iter *iter)
>>  {
>>       u64 page = offs;
>>
>>       iter->pageoffs = do_div(page, nand->memorg.pagesize);
>>       iter->page = page;
>> -     iter->offs = offs;
>> +     iter->dataleft = len;
>> +     iter->ooboffs = ooboffs;
>> +     iter->oobsize = oobsize;
>> +     iter->oobleft = ooblen;
>>  }
>>
>>  /**
>> @@ -212,13 +220,29 @@ static inline void nand_page_iter_next(struct nand_device *nand,
>>                                      struct nand_page_iter *iter)
>>  {
>>       iter->page++;
>> -     iter->offs += nand_page_size(nand) - iter->pageoffs;
>>       iter->pageoffs = 0;
>> +     if (iter->dataleft)
>> +             iter->dataleft -= min_t (int,
>> +                                      nand_page_size(nand) - iter->pageoffs,
>> +                                      iter->dataleft);
>> +     if (iter->oobleft)
>> +             iter->oobleft -= min_t(int, iter->oobsize - iter->ooboffs,
>> +                                    iter->oobleft);
>> +}
>> +
>
> Document the function.

Fix this in v5


Thanks,
Peter Pan

>
>> +static inline bool nand_page_iter_end(struct nand_device *nand,
>> +                                   struct nand_page_iter *iter)
>> +{
>> +     if (iter->dataleft || iter->oobleft)
>> +             return false;
>> +     return true;
>>  }
>>
>> -#define nand_for_each_page(nand, start, len, iter)           \
>> -     for (nand_page_iter_init(nand, start, iter);            \
>> -          (iter)->offs < (start) + (len);                    \
>> +#define nand_for_each_page(nand, start, len, ooboffs, ooblen,        \
>> +                        oobsize, iter)       \
>> +     for (nand_page_iter_init(nand, start, len, ooboffs,     \
>> +                              ooblen, oobsize, iter);        \
>> +          !nand_page_iter_end(nand, iter);           \
>>            nand_page_iter_next(nand, iter))
>>
>>  /**
>
> [1]https://github.com/bbrezillon/linux-0day/commit/f02767a662ec02a0206a0b6c5a410a38d7b7b313