Re: [PATCH v3 2/8] mtd: nand: add oob iterator in nand_for_each_page

Boris Brezillon
2017-03-17T13:11:59Z

On Thu, 16 Mar 2017 14:47:31 +0800
Peter Pan <peterpandong@micron.com> wrote:

> Iterate nand pages by both page and oob operation.
>
> Signed-off-by: Peter Pan <peterpandong@micron.com>
> ---
> include/linux/mtd/nand.h | 28 +++++++++++++++++++++++++---
> 1 file changed, 25 insertions(+), 3 deletions(-)
>
> diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
> index 4a812e6..822547e 100644
> --- a/include/linux/mtd/nand.h
> +++ b/include/linux/mtd/nand.h
> @@ -87,6 +87,9 @@ struct nand_page_iter {
> loff_t offs;
> int page;
> int pageoffs;
> + int ooboffs;
> + int oobsize;
> + size_t oobleft;

Maybe we should also add dataleft so that you don't have to pass start
and len when you call nand_page_iter_end().

> };
>
> /**
> @@ -194,6 +197,7 @@ static inline int nand_per_page_oobsize(struct nand_device *nand)
> * @iter: page iterator
> */
> static inline void nand_page_iter_init(struct nand_device *nand, loff_t offs,
> + u32 ooboffs, size_t ooblen, u32 oobsize,
> struct nand_page_iter *iter)
> {
> u64 page = offs;
> @@ -201,6 +205,9 @@ static inline void nand_page_iter_init(struct nand_device *nand, loff_t offs,
> iter->pageoffs = do_div(page, nand->memorg.pagesize);
> iter->page = page;
> iter->offs = offs;
> + iter->ooboffs = ooboffs;
> + iter->oobsize = oobsize;
> + iter->oobleft = ooblen;
> }
>
> /**
> @@ -214,11 +221,26 @@ static inline void nand_page_iter_next(struct nand_device *nand,
> iter->page++;
> iter->offs += nand_page_size(nand) - iter->pageoffs;
> iter->pageoffs = 0;
> + if (iter->oobleft)
> + iter->oobleft -= min_t(int, iter->oobsize - iter->ooboffs,
> + iter->oobleft);
> +}
> +
> +static inline bool nand_page_iter_end(struct nand_device *nand, loff_t offs,
> + u32 len, struct nand_page_iter *iter)
> +{
> + if (iter->offs < offs + len)
> + return false;
> + if (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, ooboffs, \
> + ooblen, oobsize, iter); \
> + !nand_page_iter_end(nand, start, len, iter); \
> nand_page_iter_next(nand, iter))
>
> /**