[PATCH v7 10/15] iommu/io-pgtable-arm: Implement arm_lpae_unmap_pages()
Kunkun Jiang
jiangkunkun at huawei.com
Thu Jul 15 02:31:59 PDT 2021
On 2021/6/16 21:38, Georgi Djakov wrote:
> From: "Isaac J. Manjarres" <isaacm at codeaurora.org>
>
> Implement the unmap_pages() callback for the ARM LPAE io-pgtable
> format.
>
> Signed-off-by: Isaac J. Manjarres <isaacm at codeaurora.org>
> Suggested-by: Will Deacon <will at kernel.org>
> Signed-off-by: Georgi Djakov <quic_c_gdjako at quicinc.com>
> ---
> drivers/iommu/io-pgtable-arm.c | 120 +++++++++++++++++++++++++----------------
> 1 file changed, 74 insertions(+), 46 deletions(-)
>
> diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
> index ea66b10c04c4..fe8fa0ee9c98 100644
> --- a/drivers/iommu/io-pgtable-arm.c
> +++ b/drivers/iommu/io-pgtable-arm.c
> @@ -46,6 +46,9 @@
> #define ARM_LPAE_PGD_SIZE(d) \
> (sizeof(arm_lpae_iopte) << (d)->pgd_bits)
>
> +#define ARM_LPAE_PTES_PER_TABLE(d) \
> + (ARM_LPAE_GRANULE(d) >> ilog2(sizeof(arm_lpae_iopte)))
> +
> /*
> * Calculate the index at level l used to map virtual address a using the
> * pagetable in d.
> @@ -239,22 +242,19 @@ static void __arm_lpae_sync_pte(arm_lpae_iopte *ptep, int num_entries,
> sizeof(*ptep) * num_entries, DMA_TO_DEVICE);
> }
>
> -static void __arm_lpae_set_pte(arm_lpae_iopte *ptep, arm_lpae_iopte pte,
> - int num_entries, struct io_pgtable_cfg *cfg)
> +static void __arm_lpae_clear_pte(arm_lpae_iopte *ptep, struct io_pgtable_cfg *cfg)
> {
> - int i;
>
> - for (i = 0; i < num_entries; i++)
> - ptep[i] = pte;
> + *ptep = 0;
>
> if (!cfg->coherent_walk)
> - __arm_lpae_sync_pte(ptep, num_entries, cfg);
> + __arm_lpae_sync_pte(ptep, 1, cfg);
> }
>
Thank you for providing this patchset, I am updating my patches based on it.
But can we keep __arm_lpae_set_pte()? I think it's better to remove
'num_entries'.
I am really need it. If you remove it, I have to add it back.😅
Thanks,
Kunkun Jiang
> static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
> struct iommu_iotlb_gather *gather,
> - unsigned long iova, size_t size, int lvl,
> - arm_lpae_iopte *ptep);
> + unsigned long iova, size_t size, size_t pgcount,
> + int lvl, arm_lpae_iopte *ptep);
>
> static void __arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
> phys_addr_t paddr, arm_lpae_iopte prot,
> @@ -298,7 +298,7 @@ static int arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
> size_t sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
>
> tblp = ptep - ARM_LPAE_LVL_IDX(iova, lvl, data);
> - if (__arm_lpae_unmap(data, NULL, iova + i * sz, sz,
> + if (__arm_lpae_unmap(data, NULL, iova + i * sz, sz, 1,
> lvl, tblp) != sz) {
> WARN_ON(1);
> return -EINVAL;
> @@ -526,14 +526,15 @@ static size_t arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data,
> struct iommu_iotlb_gather *gather,
> unsigned long iova, size_t size,
> arm_lpae_iopte blk_pte, int lvl,
> - arm_lpae_iopte *ptep)
> + arm_lpae_iopte *ptep, size_t pgcount)
> {
> struct io_pgtable_cfg *cfg = &data->iop.cfg;
> arm_lpae_iopte pte, *tablep;
> phys_addr_t blk_paddr;
> size_t tablesz = ARM_LPAE_GRANULE(data);
> size_t split_sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
> - int i, unmap_idx = -1;
> + int ptes_per_table = ARM_LPAE_PTES_PER_TABLE(data);
> + int i, unmap_idx_start = -1, num_entries = 0, max_entries;
>
> if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
> return 0;
> @@ -542,15 +543,18 @@ static size_t arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data,
> if (!tablep)
> return 0; /* Bytes unmapped */
>
> - if (size == split_sz)
> - unmap_idx = ARM_LPAE_LVL_IDX(iova, lvl, data);
> + if (size == split_sz) {
> + unmap_idx_start = ARM_LPAE_LVL_IDX(iova, lvl, data);
> + max_entries = ptes_per_table - unmap_idx_start;
> + num_entries = min_t(int, pgcount, max_entries);
> + }
>
> blk_paddr = iopte_to_paddr(blk_pte, data);
> pte = iopte_prot(blk_pte);
>
> - for (i = 0; i < tablesz / sizeof(pte); i++, blk_paddr += split_sz) {
> + for (i = 0; i < ptes_per_table; i++, blk_paddr += split_sz) {
> /* Unmap! */
> - if (i == unmap_idx)
> + if (i >= unmap_idx_start && i < (unmap_idx_start + num_entries))
> continue;
>
> __arm_lpae_init_pte(data, blk_paddr, pte, lvl, 1, &tablep[i]);
> @@ -568,76 +572,92 @@ static size_t arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data,
> return 0;
>
> tablep = iopte_deref(pte, data);
> - } else if (unmap_idx >= 0) {
> - io_pgtable_tlb_add_page(&data->iop, gather, iova, size);
> - return size;
> + } else if (unmap_idx_start >= 0) {
> + for (i = 0; i < num_entries; i++)
> + io_pgtable_tlb_add_page(&data->iop, gather, iova + i * size, size);
> +
> + return num_entries * size;
> }
>
> - return __arm_lpae_unmap(data, gather, iova, size, lvl, tablep);
> + return __arm_lpae_unmap(data, gather, iova, size, pgcount, lvl, tablep);
> }
>
> static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
> struct iommu_iotlb_gather *gather,
> - unsigned long iova, size_t size, int lvl,
> - arm_lpae_iopte *ptep)
> + unsigned long iova, size_t size, size_t pgcount,
> + int lvl, arm_lpae_iopte *ptep)
> {
> arm_lpae_iopte pte;
> struct io_pgtable *iop = &data->iop;
> + int i = 0, num_entries, max_entries, unmap_idx_start;
>
> /* Something went horribly wrong and we ran out of page table */
> if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
> return 0;
>
> - ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
> + unmap_idx_start = ARM_LPAE_LVL_IDX(iova, lvl, data);
> + ptep += unmap_idx_start;
> pte = READ_ONCE(*ptep);
> if (WARN_ON(!pte))
> return 0;
>
> /* If the size matches this level, we're in the right place */
> if (size == ARM_LPAE_BLOCK_SIZE(lvl, data)) {
> - __arm_lpae_set_pte(ptep, 0, 1, &iop->cfg);
> -
> - if (!iopte_leaf(pte, lvl, iop->fmt)) {
> - /* Also flush any partial walks */
> - io_pgtable_tlb_flush_walk(iop, iova, size,
> - ARM_LPAE_GRANULE(data));
> - ptep = iopte_deref(pte, data);
> - __arm_lpae_free_pgtable(data, lvl + 1, ptep);
> - } else if (iop->cfg.quirks & IO_PGTABLE_QUIRK_NON_STRICT) {
> - /*
> - * Order the PTE update against queueing the IOVA, to
> - * guarantee that a flush callback from a different CPU
> - * has observed it before the TLBIALL can be issued.
> - */
> - smp_wmb();
> - } else {
> - io_pgtable_tlb_add_page(iop, gather, iova, size);
> + max_entries = ARM_LPAE_PTES_PER_TABLE(data) - unmap_idx_start;
> + num_entries = min_t(int, pgcount, max_entries);
> +
> + while (i < num_entries) {
> + pte = READ_ONCE(*ptep);
> + if (WARN_ON(!pte))
> + break;
> +
> + __arm_lpae_clear_pte(ptep, &iop->cfg);
> +
> + if (!iopte_leaf(pte, lvl, iop->fmt)) {
> + /* Also flush any partial walks */
> + io_pgtable_tlb_flush_walk(iop, iova + i * size, size,
> + ARM_LPAE_GRANULE(data));
> + __arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data));
> + } else if (iop->cfg.quirks & IO_PGTABLE_QUIRK_NON_STRICT) {
> + /*
> + * Order the PTE update against queueing the IOVA, to
> + * guarantee that a flush callback from a different CPU
> + * has observed it before the TLBIALL can be issued.
> + */
> + smp_wmb();
> + } else {
> + io_pgtable_tlb_add_page(iop, gather, iova + i * size, size);
> + }
> +
> + ptep++;
> + i++;
> }
>
> - return size;
> + return i * size;
> } else if (iopte_leaf(pte, lvl, iop->fmt)) {
> /*
> * Insert a table at the next level to map the old region,
> * minus the part we want to unmap
> */
> return arm_lpae_split_blk_unmap(data, gather, iova, size, pte,
> - lvl + 1, ptep);
> + lvl + 1, ptep, pgcount);
> }
>
> /* Keep on walkin' */
> ptep = iopte_deref(pte, data);
> - return __arm_lpae_unmap(data, gather, iova, size, lvl + 1, ptep);
> + return __arm_lpae_unmap(data, gather, iova, size, pgcount, lvl + 1, ptep);
> }
>
> -static size_t arm_lpae_unmap(struct io_pgtable_ops *ops, unsigned long iova,
> - size_t size, struct iommu_iotlb_gather *gather)
> +static size_t arm_lpae_unmap_pages(struct io_pgtable_ops *ops, unsigned long iova,
> + size_t pgsize, size_t pgcount,
> + struct iommu_iotlb_gather *gather)
> {
> struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
> struct io_pgtable_cfg *cfg = &data->iop.cfg;
> arm_lpae_iopte *ptep = data->pgd;
> long iaext = (s64)iova >> cfg->ias;
>
> - if (WARN_ON(!size || (size & cfg->pgsize_bitmap) != size))
> + if (WARN_ON(!pgsize || (pgsize & cfg->pgsize_bitmap) != pgsize || !pgcount))
> return 0;
>
> if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1)
> @@ -645,7 +665,14 @@ static size_t arm_lpae_unmap(struct io_pgtable_ops *ops, unsigned long iova,
> if (WARN_ON(iaext))
> return 0;
>
> - return __arm_lpae_unmap(data, gather, iova, size, data->start_level, ptep);
> + return __arm_lpae_unmap(data, gather, iova, pgsize, pgcount,
> + data->start_level, ptep);
> +}
> +
> +static size_t arm_lpae_unmap(struct io_pgtable_ops *ops, unsigned long iova,
> + size_t size, struct iommu_iotlb_gather *gather)
> +{
> + return arm_lpae_unmap_pages(ops, iova, size, 1, gather);
> }
>
> static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
> @@ -761,6 +788,7 @@ arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
> data->iop.ops = (struct io_pgtable_ops) {
> .map = arm_lpae_map,
> .unmap = arm_lpae_unmap,
> + .unmap_pages = arm_lpae_unmap_pages,
> .iova_to_phys = arm_lpae_iova_to_phys,
> };
>
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