Hi,
Some minor nitpicks below.
On Friday, July 05, 2013 09:29:18 PM Cho KyongHo wrote:
> This prevents allocating lv2 page table for the lv1 page table entry
> that already has 1MB page mapping. In addition some BUG_ON() is
> changed to WARN_ON().
>
> Signed-off-by: Cho KyongHo <pullip.cho@xxxxxxxxxxx>
> ---
> drivers/iommu/exynos-iommu.c | 34 ++++++++++++++++++++++++++--------
> 1 files changed, 26 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
> index e3be3e5..2bfe9fa 100644
> --- a/drivers/iommu/exynos-iommu.c
> +++ b/drivers/iommu/exynos-iommu.c
> @@ -862,12 +862,14 @@ static unsigned long *alloc_lv2entry(unsigned long *sent, unsigned long iova,
> pent = kzalloc(LV2TABLE_SIZE, GFP_ATOMIC);
> BUG_ON((unsigned long)pent & (LV2TABLE_SIZE - 1));
> if (!pent)
> - return NULL;
> + return ERR_PTR(-ENOMEM);
>
> *sent = mk_lv1ent_page(__pa(pent));
> *pgcounter = NUM_LV2ENTRIES;
> pgtable_flush(pent, pent + NUM_LV2ENTRIES);
> pgtable_flush(sent, sent + 1);
> + } else if (lv1ent_section(sent)) {
> + return ERR_PTR(-EADDRINUSE);
> }
>
> return page_entry(sent, iova);
> @@ -944,16 +946,16 @@ static int exynos_iommu_map(struct iommu_domain *domain, unsigned long iova,
> pent = alloc_lv2entry(entry, iova,
> &priv->lv2entcnt[lv1ent_offset(iova)]);
>
> - if (!pent)
> - ret = -ENOMEM;
> + if (IS_ERR(pent))
> + ret = PTR_ERR(pent);
> else
> ret = lv2set_page(pent, paddr, size,
> &priv->lv2entcnt[lv1ent_offset(iova)]);
> }
>
> if (ret) {
> - pr_debug("%s: Failed to map iova 0x%lx/0x%x bytes\n",
> - __func__, iova, size);
> + pr_err("%s: Failed(%d) to map iova 0x%#x bytes @ %#lx\n",
> + __func__, ret, size, iova);
> }
Intendation is a bit weird, it should be more like:
pr_err("%s: Failed(%d) to map iova 0x%#x bytes @ %#lx\n",
__func__, ret, size, iova);
to be consistent with the rest of the driver.
You could have also removed superfluous braces while at it.
> spin_unlock_irqrestore(&priv->pgtablelock, flags);
> @@ -968,6 +970,7 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
> struct sysmmu_drvdata *data;
> unsigned long flags;
> unsigned long *ent;
> + size_t err_page;
>
> BUG_ON(priv->pgtable == NULL);
>
> @@ -976,7 +979,8 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
> ent = section_entry(priv->pgtable, iova);
>
> if (lv1ent_section(ent)) {
> - BUG_ON(size < SECT_SIZE);
> + if (WARN_ON(size < SECT_SIZE))
> + goto err;
>
> *ent = 0;
> pgtable_flush(ent, ent + 1);
> @@ -1008,7 +1012,8 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
> }
>
> /* lv1ent_large(ent) == true here */
> - BUG_ON(size < LPAGE_SIZE);
> + if (WARN_ON(size < LPAGE_SIZE))
> + goto err;
>
> memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE);
> pgtable_flush(ent, ent + SPAGES_PER_LPAGE);
> @@ -1023,8 +1028,21 @@ done:
> sysmmu_tlb_invalidate_entry(data->dev, iova);
> spin_unlock_irqrestore(&priv->lock, flags);
>
> -
> return size;
> +err:
> + spin_unlock_irqrestore(&priv->pgtablelock, flags);
> +
> + err_page = (
> + ((unsigned long)ent - (unsigned long)priv->pgtable)
> + < (NUM_LV1ENTRIES * sizeof(long))
Maybe you could add LV1TABLE_SIZE define and use it here (there is
already a LV2TABLE_SIZE define)?
> + ) ? SECT_SIZE : LPAGE_SIZE;
It also seems that err_page should be of unsigned long type, no need
to make it size_t one.
The above code is quite ugly currently, it could be rewritten into
something prettier, i.e.:
err_page = (unsigned long)ent - (unsigned long)priv->pgtable;
err_page = (err_page < LV1TABLE_SIZE) ? SECT_SIZE : LPAGE_SIZE;
> + pr_err("%s: Failed due to size(%#lx) @ %#x is"\
> + " smaller than page size %#x\n",
> + __func__, iova, size, err_page);
Aren't iova and size arguments interchanged here?
> +
> + return 0;
There is an intendation issue here (extra whitespaces).
> +
> }
>
> static phys_addr_t exynos_iommu_iova_to_phys(struct iommu_domain *domain,
Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics
--
To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
