Message ID | 02f7510acb9b6dbb3a5a6cd5bb287762eb4d22c1.1430430153.git.hramrach@gmail.com |
---|---|
State | Rejected |
Headers | show |
On Thursday, April 30, 2015 at 03:33:47 PM, Michal Suchanek wrote: > The 'retlen' points to a variable representing the number of data bytes > written/read (see include/linux/mtd/mtd.h) by the current invocation of > the function. This variable must be set, not incremented. > > v2: clearer commit message This V2 goes past the diffstat, so that when the patch is applied, it doesn't end up in the log. > Signed-off-by: Michal Suchanek <hramrach@gmail.com> > Acked-by: Marek Vasut <marex@denx.de> > --- > drivers/mtd/devices/m25p80.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Aka. V<n> changes go here. I don't think there's a need to repost tho :) > diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c > index 7c8b169..0b2bc21 100644 > --- a/drivers/mtd/devices/m25p80.c > +++ b/drivers/mtd/devices/m25p80.c > @@ -102,7 +102,7 @@ static void m25p80_write(struct spi_nor *nor, loff_t > to, size_t len, > > spi_sync(spi, &m); > > - *retlen += m.actual_length - cmd_sz; > + *retlen = m.actual_length - cmd_sz; > } > > static inline unsigned int m25p80_rx_nbits(struct spi_nor *nor) Best regards, Marek Vasut
On Thu, Apr 30, 2015 at 03:33:47PM +0200, Michal Suchanek wrote: > The 'retlen' points to a variable representing the number of data bytes > written/read (see include/linux/mtd/mtd.h) by the current invocation of > the function. This variable must be set, not incremented. > > v2: clearer commit message > > Signed-off-by: Michal Suchanek <hramrach@gmail.com> > Acked-by: Marek Vasut <marex@denx.de> > --- > drivers/mtd/devices/m25p80.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c > index 7c8b169..0b2bc21 100644 > --- a/drivers/mtd/devices/m25p80.c > +++ b/drivers/mtd/devices/m25p80.c > @@ -102,7 +102,7 @@ static void m25p80_write(struct spi_nor *nor, loff_t to, size_t len, > > spi_sync(spi, &m); > > - *retlen += m.actual_length - cmd_sz; > + *retlen = m.actual_length - cmd_sz; This is very wrong. It gets a little better once you add your next patches (which are also not good) since those patches reinterpret the usage of retlen, but this one definitely does *not* stand a lone. I'll admit the API is a little odd here, but the callers of this function (see spi_nor_write()) actually depend on calling this multiple times, with the value incrementing each time so we get a summary total. You're now clobbering this value. I'm willing to accept patches to improve this API, if you think that would help. Or to add comments that document this. > } > > static inline unsigned int m25p80_rx_nbits(struct spi_nor *nor) Also, I'm a little confused because you sent two different patch series very close to each other, and this patch is in both of them. Please don't do that. Either send a single patch series that contains all patches (and is versions v2, v3, etc., as you revise the whole thing) or send completely independent patch series. Don't include the same patch in different series. Anyway, please consider my comments, and when you have something better, please resend everything. I'm not going to take either series as-is. Thanks, Brian
Hello, On 21 May 2015 at 01:45, Brian Norris <computersforpeace@gmail.com> wrote: > On Thu, Apr 30, 2015 at 03:33:47PM +0200, Michal Suchanek wrote: >> The 'retlen' points to a variable representing the number of data bytes >> written/read (see include/linux/mtd/mtd.h) by the current invocation of >> the function. This variable must be set, not incremented. >> >> v2: clearer commit message >> >> Signed-off-by: Michal Suchanek <hramrach@gmail.com> >> Acked-by: Marek Vasut <marex@denx.de> >> --- >> drivers/mtd/devices/m25p80.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c >> index 7c8b169..0b2bc21 100644 >> --- a/drivers/mtd/devices/m25p80.c >> +++ b/drivers/mtd/devices/m25p80.c >> @@ -102,7 +102,7 @@ static void m25p80_write(struct spi_nor *nor, loff_t to, size_t len, >> >> spi_sync(spi, &m); >> >> - *retlen += m.actual_length - cmd_sz; >> + *retlen = m.actual_length - cmd_sz; > > This is very wrong. It gets a little better once you add your next > patches (which are also not good) since those patches reinterpret the > usage of retlen, but this one definitely does *not* stand a lone. > > I'll admit the API is a little odd here, but the callers of this > function (see spi_nor_write()) actually depend on calling this multiple > times, with the value incrementing each time so we get a summary total. > You're now clobbering this value. > > I'm willing to accept patches to improve this API, if you think that > would help. Or to add comments that document this. Yes, the only user of the retlen value ignores it but passes it on so without the following patch this one makes the passed on value different from before. For m25p80 this would be fixed by truncating the write in the driver and setting actual_length appropriately rather than returning an error when the message is too long. It might possibly break other drivers, though. Thanks Michal
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index 7c8b169..0b2bc21 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -102,7 +102,7 @@ static void m25p80_write(struct spi_nor *nor, loff_t to, size_t len, spi_sync(spi, &m); - *retlen += m.actual_length - cmd_sz; + *retlen = m.actual_length - cmd_sz; } static inline unsigned int m25p80_rx_nbits(struct spi_nor *nor)