Re: [PATCH V3] mmc: mmc_test: Pass different sg lists for non-blocking requests

[Ulf Hansson <ulf.hansson@linaro.org>]

On Wed, 26 Feb 2020 at 11:58, Veerabhadrarao Badiganti
<vbadigan@codeaurora.org> wrote:
>
> Supply a separate sg list for each of the request in non-blocking
> IO test cases where two requests will be issued at same time.
>
> Otherwise, sg memory may get unmapped when a request is done while
> same memory is being accessed by controller from the other request,
> and it leads to iommu errors with below call stack:
>
>         __arm_lpae_unmap+0x2e0/0x478
>         arm_lpae_unmap+0x54/0x70
>         arm_smmu_unmap+0x64/0xa4
>         __iommu_unmap+0xb8/0x1f0
>         iommu_unmap_fast+0x38/0x48
>         __iommu_dma_unmap+0x88/0x108
>         iommu_dma_unmap_sg+0x90/0xa4
>         sdhci_post_req+0x5c/0x78
>         mmc_test_start_areq+0x10c/0x120 [mmc_test]
>         mmc_test_area_io_seq+0x150/0x264 [mmc_test]
>         mmc_test_rw_multiple+0x174/0x1c0 [mmc_test]
>         mmc_test_rw_multiple_sg_len+0x44/0x6c [mmc_test]
>         mmc_test_profile_sglen_wr_nonblock_perf+0x6c/0x94 [mmc_test]
>         mtf_test_write+0x238/0x3cc [mmc_test]
>
> Signed-off-by: Veerabhadrarao Badiganti <vbadigan@codeaurora.org>
> Reviewed-by: Stephen Boyd <swboyd@chromium.org>
> Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>

Applied for next, thanks!

Kind regards
Uffe


> ---
> Changes since V2:
>         - Simplfied mmc_test_nonblock_transter() function aruguments.
>
> Changes since V1:
>         - Freeing-up sg_areq memory.
>         - Added check to ensure sg length is equal for both the sg-lists
>           supplied in case of non-blocking requests.
> ---
>  drivers/mmc/core/mmc_test.c | 52 ++++++++++++++++++++++++++++++++++-----------
>  1 file changed, 40 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/mmc/core/mmc_test.c b/drivers/mmc/core/mmc_test.c
> index 492dd45..c21b3cb 100644
> --- a/drivers/mmc/core/mmc_test.c
> +++ b/drivers/mmc/core/mmc_test.c
> @@ -71,6 +71,7 @@ struct mmc_test_mem {
>   * @sg_len: length of currently mapped scatterlist @sg
>   * @mem: allocated memory
>   * @sg: scatterlist
> + * @sg_areq: scatterlist for non-blocking request
>   */
>  struct mmc_test_area {
>         unsigned long max_sz;
> @@ -82,6 +83,7 @@ struct mmc_test_area {
>         unsigned int sg_len;
>         struct mmc_test_mem *mem;
>         struct scatterlist *sg;
> +       struct scatterlist *sg_areq;
>  };
>
>  /**
> @@ -836,14 +838,16 @@ static int mmc_test_start_areq(struct mmc_test_card *test,
>  }
>
>  static int mmc_test_nonblock_transfer(struct mmc_test_card *test,
> -                                     struct scatterlist *sg, unsigned sg_len,
> -                                     unsigned dev_addr, unsigned blocks,
> -                                     unsigned blksz, int write, int count)
> +                                     unsigned int dev_addr, int write,
> +                                     int count)
>  {
>         struct mmc_test_req *rq1, *rq2;
>         struct mmc_request *mrq, *prev_mrq;
>         int i;
>         int ret = RESULT_OK;
> +       struct mmc_test_area *t = &test->area;
> +       struct scatterlist *sg = t->sg;
> +       struct scatterlist *sg_areq = t->sg_areq;
>
>         rq1 = mmc_test_req_alloc();
>         rq2 = mmc_test_req_alloc();
> @@ -857,8 +861,8 @@ static int mmc_test_nonblock_transfer(struct mmc_test_card *test,
>
>         for (i = 0; i < count; i++) {
>                 mmc_test_req_reset(container_of(mrq, struct mmc_test_req, mrq));
> -               mmc_test_prepare_mrq(test, mrq, sg, sg_len, dev_addr, blocks,
> -                                    blksz, write);
> +               mmc_test_prepare_mrq(test, mrq, sg, t->sg_len, dev_addr,
> +                                    t->blocks, 512, write);
>                 ret = mmc_test_start_areq(test, mrq, prev_mrq);
>                 if (ret)
>                         goto err;
> @@ -867,7 +871,8 @@ static int mmc_test_nonblock_transfer(struct mmc_test_card *test,
>                         prev_mrq = &rq2->mrq;
>
>                 swap(mrq, prev_mrq);
> -               dev_addr += blocks;
> +               swap(sg, sg_areq);
> +               dev_addr += t->blocks;
>         }
>
>         ret = mmc_test_start_areq(test, NULL, prev_mrq);
> @@ -1396,10 +1401,11 @@ static int mmc_test_no_highmem(struct mmc_test_card *test)
>   * Map sz bytes so that it can be transferred.
>   */
>  static int mmc_test_area_map(struct mmc_test_card *test, unsigned long sz,
> -                            int max_scatter, int min_sg_len)
> +                            int max_scatter, int min_sg_len, bool nonblock)
>  {
>         struct mmc_test_area *t = &test->area;
>         int err;
> +       unsigned int sg_len = 0;
>
>         t->blocks = sz >> 9;
>
> @@ -1411,6 +1417,22 @@ static int mmc_test_area_map(struct mmc_test_card *test, unsigned long sz,
>                 err = mmc_test_map_sg(t->mem, sz, t->sg, 1, t->max_segs,
>                                       t->max_seg_sz, &t->sg_len, min_sg_len);
>         }
> +
> +       if (err || !nonblock)
> +               goto err;
> +
> +       if (max_scatter) {
> +               err = mmc_test_map_sg_max_scatter(t->mem, sz, t->sg_areq,
> +                                                 t->max_segs, t->max_seg_sz,
> +                                                 &sg_len);
> +       } else {
> +               err = mmc_test_map_sg(t->mem, sz, t->sg_areq, 1, t->max_segs,
> +                                     t->max_seg_sz, &sg_len, min_sg_len);
> +       }
> +       if (!err && sg_len != t->sg_len)
> +               err = -EINVAL;
> +
> +err:
>         if (err)
>                 pr_info("%s: Failed to map sg list\n",
>                        mmc_hostname(test->card->host));
> @@ -1440,7 +1462,6 @@ static int mmc_test_area_io_seq(struct mmc_test_card *test, unsigned long sz,
>         struct timespec64 ts1, ts2;
>         int ret = 0;
>         int i;
> -       struct mmc_test_area *t = &test->area;
>
>         /*
>          * In the case of a maximally scattered transfer, the maximum transfer
> @@ -1458,15 +1479,14 @@ static int mmc_test_area_io_seq(struct mmc_test_card *test, unsigned long sz,
>                         sz = max_tfr;
>         }
>
> -       ret = mmc_test_area_map(test, sz, max_scatter, min_sg_len);
> +       ret = mmc_test_area_map(test, sz, max_scatter, min_sg_len, nonblock);
>         if (ret)
>                 return ret;
>
>         if (timed)
>                 ktime_get_ts64(&ts1);
>         if (nonblock)
> -               ret = mmc_test_nonblock_transfer(test, t->sg, t->sg_len,
> -                                dev_addr, t->blocks, 512, write, count);
> +               ret = mmc_test_nonblock_transfer(test, dev_addr, write, count);
>         else
>                 for (i = 0; i < count && ret == 0; i++) {
>                         ret = mmc_test_area_transfer(test, dev_addr, write);
> @@ -1525,6 +1545,7 @@ static int mmc_test_area_cleanup(struct mmc_test_card *test)
>         struct mmc_test_area *t = &test->area;
>
>         kfree(t->sg);
> +       kfree(t->sg_areq);
>         mmc_test_free_mem(t->mem);
>
>         return 0;
> @@ -1584,6 +1605,13 @@ static int mmc_test_area_init(struct mmc_test_card *test, int erase, int fill)
>                 goto out_free;
>         }
>
> +       t->sg_areq = kmalloc_array(t->max_segs, sizeof(*t->sg_areq),
> +                                  GFP_KERNEL);
> +       if (!t->sg_areq) {
> +               ret = -ENOMEM;
> +               goto out_free;
> +       }
> +
>         t->dev_addr = mmc_test_capacity(test->card) / 2;
>         t->dev_addr -= t->dev_addr % (t->max_sz >> 9);
>
> @@ -2468,7 +2496,7 @@ static int __mmc_test_cmds_during_tfr(struct mmc_test_card *test,
>         if (!(test->card->host->caps & MMC_CAP_CMD_DURING_TFR))
>                 return RESULT_UNSUP_HOST;
>
> -       ret = mmc_test_area_map(test, sz, 0, 0);
> +       ret = mmc_test_area_map(test, sz, 0, 0, use_areq);
>         if (ret)
>                 return ret;
>
> --
> Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc., is a member of Code Aurora Forum, a Linux Foundation Collaborative Project