| Message ID | 1534314823-14048-1-git-send-email-chuanhua.han@nxp.com |
|---|---|
| State | Rejected |
| Headers | show |
| Series | mtd: m25p80: consider max message size in m25p80_read when use the spi_mem_xx() API | expand |
Hi Chuanhua, On Wed, 15 Aug 2018 14:33:43 +0800 Chuanhua Han <chuanhua.han@nxp.com> wrote: > Consider a message size limit when calculating the maximum amount > of data that can be read. > > Signed-off-by: Chuanhua Han <chuanhua.han@nxp.com> > --- > drivers/mtd/devices/m25p80.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c > index e84563d..87efa56 100644 > --- a/drivers/mtd/devices/m25p80.c > +++ b/drivers/mtd/devices/m25p80.c > @@ -128,7 +128,12 @@ static ssize_t m25p80_read(struct spi_nor *nor, loff_t from, size_t len, > op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8; > > while (remaining) { > - op.data.nbytes = remaining < UINT_MAX ? remaining : UINT_MAX; > + op.data.nbytes = min3(remaining, > + spi_max_transfer_size(flash->spimem->spi), > + spi_max_message_size(flash->spimem->spi) - > + sizeof(op.cmd.opcode) - > + op.addr.nbytes - > + op.dummy.nbytes); Nope, this sort of things should go in the SPI controller driver ->adjust_op_size() hook or directly in spi_mem_adjust_op_size() if it's generic enough (which doesn't seem to be the case since your not counting the opcode, addr and dummy bytes in the message length). Regards, Boris
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index e84563d..87efa56 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -128,7 +128,12 @@ static ssize_t m25p80_read(struct spi_nor *nor, loff_t from, size_t len, op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8; while (remaining) { - op.data.nbytes = remaining < UINT_MAX ? remaining : UINT_MAX; + op.data.nbytes = min3(remaining, + spi_max_transfer_size(flash->spimem->spi), + spi_max_message_size(flash->spimem->spi) - + sizeof(op.cmd.opcode) - + op.addr.nbytes - + op.dummy.nbytes); ret = spi_mem_adjust_op_size(flash->spimem, &op); if (ret) return ret;
Consider a message size limit when calculating the maximum amount of data that can be read. Signed-off-by: Chuanhua Han <chuanhua.han@nxp.com> --- drivers/mtd/devices/m25p80.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)