RE: [PATCH v4 7/7] mtd: spi-nor: add read loop

From: Hou Zhiqiang
Date: Wed Nov 04 2015 - 22:55:37 EST


Hi Michal,

Does this have any updates?

Thanks,
Zhiqiang

> -----Original Message-----
> From: Michal Suchanek [mailto:hramrach@xxxxxxxxx]
> Sent: 2015å8æ14æ 18:08
> To: Andrew Murray
> Cc: Hou Zhiqiang-B48286; Huang Shijie; David Woodhouse; Brian Norris; Xu
> Han-B45815; RafaÅ MiÅecki; Huang Shijie; Ben Hutchings; Marek Vasut;
> Gabor Juhos; Bean Huo éææ,; MTD Maling List; LKML
> Subject: Re: [PATCH v4 7/7] mtd: spi-nor: add read loop
>
> On 14 August 2015 at 12:02, Andrew Murray <amurray@xxxxxxxxxxxxxxxxxxx>
> wrote:
> > On 14 August 2015 at 10:23, Michal Suchanek <hramrach@xxxxxxxxx> wrote:
> >> mtdblock and ubi do not handle the situation when read returns less
> >> data than requested. Loop in spi-nor until buffer is filled or an
> >> error is returned.
> >>
> >> Signed-off-by: Michal Suchanek <hramrach@xxxxxxxxx>
> >> ---
> >> drivers/mtd/spi-nor/spi-nor.c | 20 ++++++++++++++------
> >> 1 file changed, 14 insertions(+), 6 deletions(-)
> >>
> >> diff --git a/drivers/mtd/spi-nor/spi-nor.c
> >> b/drivers/mtd/spi-nor/spi-nor.c index e0ae9cf..246fac7 100644
> >> --- a/drivers/mtd/spi-nor/spi-nor.c
> >> +++ b/drivers/mtd/spi-nor/spi-nor.c
> >> @@ -738,14 +738,22 @@ static int spi_nor_read(struct mtd_info *mtd,
> loff_t from, size_t len,
> >> if (ret)
> >> return ret;
> >>
> >> - ret = nor->read(nor, from, len, buf);
> >> + while (len) {
> >> + ret = nor->read(nor, from, len, buf);
> >> + if (ret <= 0)
> >> + goto read_err;
> >> +
> >> + BUG_ON(ret > len);
> >> + *retlen += ret;
> >
> > Is *retlen initialized to 0 anywhere?
>
> It's initialized in mtdcore and passed into mtd->_read.
>
> Yes, the interface is really awkward.
>
> int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t
> *retlen,
> u_char *buf)
> {
> int ret_code;
> *retlen = 0;
>
>
> Thanks
>
> Michal
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