Re: [PATCH v3 1/8] mtd: nand: add more helpers in nand.h

[Boris Brezillon <boris.brezillon@free-electrons.com>]

On Thu, 16 Mar 2017 14:47:30 +0800
Peter Pan <peterpandong@micron.com> wrote:

> This commit adds some helpers in nand.h
>     nand_size()
>     valid_nand_address()
>     valid_nand_oob_ops()
>     nand_oob_ops_across_page()
>     valid_nand_erase_ops()
> 
> Signed-off-by: Peter Pan <peterpandong@micron.com>
> ---
>  include/linux/mtd/nand.h | 59 ++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 59 insertions(+)
> 
> diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
> index c2197b4..4a812e6 100644
> --- a/include/linux/mtd/nand.h
> +++ b/include/linux/mtd/nand.h
> @@ -410,6 +410,65 @@ static inline int nand_neraseblocks(struct nand_device *nand)
>  }
>  
>  /**
> + * nand_size - Get NAND size
> + * @nand: NAND device
> + *
> + * Returns the total size exposed by @nand.
> + */
> +static inline u64 nand_size(struct nand_device *nand)
> +{
> +	return nand->memorg.ndies * nand->memorg.diesize;
> +}
> +
> +static inline bool valid_nand_address(struct nand_device *nand, loff_t addr)

Please keep consistent prefixes. Maybe we should name it
nand_check_address(), return -EINVAL if it's wrong and 0 otherwise:

static inline int nand_check_address(struct nand_device *nand,
				     loff_t addr)
{
	return addr < nand_size(nand) ? 0 : -EINVAL;
}

> +{
> +	return addr < nand_size(nand);
> +}
> +
> +static inline bool valid_nand_oob_ops(struct nand_device *nand, loff_t start,
> +				      struct mtd_oob_ops *ops)
> +{
> +	struct mtd_info *mtd = nand_to_mtd(nand);
> +	int ooblen = ops->mode == MTD_OPS_AUTO_OOB ?
> +		mtd->oobavail : mtd->oobsize;
> +
> +	if (ops->ooboffs >= ooblen)
> +		return false;
> +	if (ops->ooboffs + ops->ooblen >
> +	    (nand_len_to_pages(nand, nand_size(nand)) -
> +			       nand_offs_to_page(nand, start)) * ooblen)
> +		return false;
> +
> +	return true;
> +}

Ditto.

> +
> +static inline bool nand_oob_ops_across_page(struct nand_device *nand,
> +					    struct mtd_oob_ops *ops)
> +{
> +	struct mtd_info *mtd = nand_to_mtd(nand);
> +	int ooblen = ops->mode == MTD_OPS_AUTO_OOB ?
> +		     mtd->oobavail : mtd->oobsize;
> +
> +	return (ops->ooboffs + ops->ooblen) > ooblen;
> +}
> +
> +static inline bool valid_nand_erase_ops(struct nand_device *nand,
> +					struct erase_info *einfo)

Ditto.

> +{
> +	/* check address align on block boundary */
> +	if (einfo->addr & (nand_eraseblock_size(nand) - 1))
> +		return false;
> +	/* check lendth align on block boundary */
> +	if (einfo->len & (nand_eraseblock_size(nand) - 1))
> +		return false;
> +	/* Do not allow erase past end of device */
> +	if ((einfo->addr + einfo->len) > nand_size(nand))
> +		return false;
> +
> +	return true;
> +}
> +
> +/**
>   * nand_register - Register a NAND device
>   * @nand: NAND device
>   *