> On 4/09/24 17:52, Avri Altman wrote:
> > ACMD22 is used to verify the previously write operation. Normally, it
> > returns the number of written sectors as u32. SDUC, however, returns
> > it as u64. This is not a superfluous requirement, because SDUC writes
> > may exceeds 2TB. For Linux mmc however, the previously write
> > operation could not be more than the block layer limits, thus we make
> > room for a
> > u64 and cast the returning value to u32.
> >
> > Signed-off-by: Avri Altman <avri.altman@xxxxxxx>
> > ---
> > drivers/mmc/core/block.c | 29 +++++++++++++++++++++++------
> > 1 file changed, 23 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index
> > 50d37c4f5a50..f36611512a1d 100644
> > --- a/drivers/mmc/core/block.c
> > +++ b/drivers/mmc/core/block.c
> > @@ -50,6 +50,7 @@
> > #include <linux/mmc/sd.h>
> >
> > #include <linux/uaccess.h>
> > +#include <asm/unaligned.h>
> >
> > #include "queue.h"
> > #include "block.h"
> > @@ -994,11 +995,10 @@ static int mmc_sd_num_wr_blocks(struct mmc_card
> *card, u32 *written_blocks)
> > int err;
> > u32 result;
> > __be32 *blocks;
> > -
> > + u8 resp_sz;
>
> Could do the initialization here i.e.
>
> u8 resp_sz = mmc_card_ult_capacity(card) ? 8 : 4;
Done.
>
> > struct mmc_request mrq = {};
> > struct mmc_command cmd = {};
> > struct mmc_data data = {};
> > -
> > struct scatterlist sg;
> >
> > err = mmc_app_cmd(card->host, card); @@ -1009,7 +1009,14 @@
> > static int mmc_sd_num_wr_blocks(struct mmc_card *card, u32
> *written_blocks)
> > cmd.arg = 0;
> > cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
> >
> > - data.blksz = 4;
> > + /*
> > + * Normally, ACMD22 returns the number of written sectors as u32.
> > + * SDUC, however, returns it as u64. This is not a superfluous
> > + * requirement, because SDUC writes may exceed 2TB.
> > + */
> > + resp_sz = mmc_card_ult_capacity(card) ? 8 : 4;
> > +
> > + data.blksz = resp_sz;
> > data.blocks = 1;
> > data.flags = MMC_DATA_READ;
> > data.sg = &sg;
> > @@ -1019,15 +1026,25 @@ static int mmc_sd_num_wr_blocks(struct
> mmc_card *card, u32 *written_blocks)
> > mrq.cmd = &cmd;
> > mrq.data = &data;
> >
> > - blocks = kmalloc(4, GFP_KERNEL);
> > + blocks = kmalloc(resp_sz, GFP_KERNEL);
>
> Separate issue, but this should probably be GFP_NOIO, or just have the buffer in
> mmc_host or mmc_card
OK. Mark this to be fixed in a subsequent patch.
>
> > if (!blocks)
> > return -ENOMEM;
> >
> > - sg_init_one(&sg, blocks, 4);
> > + sg_init_one(&sg, blocks, resp_sz);
> >
> > mmc_wait_for_req(card->host, &mrq);
> >
> > - result = ntohl(*blocks);
> > + if (mmc_card_ult_capacity(card)) {
> > + u64 blocks_64 = get_unaligned_be64(blocks);
> > + /*
> > + * For Linux mmc however, the previously write operation could
> > + * not be more than the block layer limits, thus just make room
> > + * for a u64 and cast the response back to u32.
> > + */
> > + result = blocks_64 > UINT_MAX ? UINT_MAX :
> > + (u32)blocks_64;
>
> Perhaps:
> result = clamp_val(get_unaligned_be64(blocks), 0, UINT_MAX);
Done.
Thanks,
Avri
>
> > + } else {
> > + result = ntohl(*blocks);
> > + }
> > kfree(blocks);
> >
> > if (cmd.error || data.error)
