[PATCH v6 11/15] iommu/io-pgtable-arm: Implement arm_lpae_map_pages()

From: Georgi Djakov
Date: Tue Jun 15 2021 - 13:09:26 EST


From: "Isaac J. Manjarres" <isaacm@xxxxxxxxxxxxxx>

Implement the map_pages() callback for the ARM LPAE io-pgtable
format.

Signed-off-by: Isaac J. Manjarres <isaacm@xxxxxxxxxxxxxx>
Signed-off-by: Georgi Djakov <quic_c_gdjako@xxxxxxxxxxx>
---
drivers/iommu/io-pgtable-arm.c | 41 +++++++++++++++++++++++++++++++----------
1 file changed, 31 insertions(+), 10 deletions(-)

diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index 1b690911995a..6a6af9b0678e 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -344,20 +344,30 @@ static arm_lpae_iopte arm_lpae_install_table(arm_lpae_iopte *table,
}

static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova,
- phys_addr_t paddr, size_t size, arm_lpae_iopte prot,
- int lvl, arm_lpae_iopte *ptep, gfp_t gfp)
+ phys_addr_t paddr, size_t size, size_t pgcount,
+ arm_lpae_iopte prot, int lvl, arm_lpae_iopte *ptep,
+ gfp_t gfp, size_t *mapped)
{
arm_lpae_iopte *cptep, pte;
size_t block_size = ARM_LPAE_BLOCK_SIZE(lvl, data);
size_t tblsz = ARM_LPAE_GRANULE(data);
struct io_pgtable_cfg *cfg = &data->iop.cfg;
+ int ret = 0, num_entries, max_entries, map_idx_start;

/* Find our entry at the current level */
- ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
+ map_idx_start = ARM_LPAE_LVL_IDX(iova, lvl, data);
+ ptep += map_idx_start;

/* If we can install a leaf entry at this level, then do so */
- if (size == block_size)
- return arm_lpae_init_pte(data, iova, paddr, prot, lvl, 1, ptep);
+ if (size == block_size) {
+ max_entries = ARM_LPAE_PTES_PER_TABLE(data) - map_idx_start;
+ num_entries = min_t(int, pgcount, max_entries);
+ ret = arm_lpae_init_pte(data, iova, paddr, prot, lvl, num_entries, ptep);
+ if (!ret && mapped)
+ *mapped += num_entries * size;
+
+ return ret;
+ }

/* We can't allocate tables at the final level */
if (WARN_ON(lvl >= ARM_LPAE_MAX_LEVELS - 1))
@@ -386,7 +396,8 @@ static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova,
}

/* Rinse, repeat */
- return __arm_lpae_map(data, iova, paddr, size, prot, lvl + 1, cptep, gfp);
+ return __arm_lpae_map(data, iova, paddr, size, pgcount, prot, lvl + 1,
+ cptep, gfp, mapped);
}

static arm_lpae_iopte arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable *data,
@@ -453,8 +464,9 @@ static arm_lpae_iopte arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable *data,
return pte;
}

-static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova,
- phys_addr_t paddr, size_t size, int iommu_prot, gfp_t gfp)
+static int arm_lpae_map_pages(struct io_pgtable_ops *ops, unsigned long iova,
+ phys_addr_t paddr, size_t pgsize, size_t pgcount,
+ int iommu_prot, gfp_t gfp, size_t *mapped)
{
struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
struct io_pgtable_cfg *cfg = &data->iop.cfg;
@@ -463,7 +475,7 @@ static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova,
arm_lpae_iopte prot;
long iaext = (s64)iova >> cfg->ias;

- if (WARN_ON(!size || (size & cfg->pgsize_bitmap) != size))
+ if (WARN_ON(!pgsize || (pgsize & cfg->pgsize_bitmap) != pgsize))
return -EINVAL;

if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1)
@@ -476,7 +488,8 @@ static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova,
return 0;

prot = arm_lpae_prot_to_pte(data, iommu_prot);
- ret = __arm_lpae_map(data, iova, paddr, size, prot, lvl, ptep, gfp);
+ ret = __arm_lpae_map(data, iova, paddr, pgsize, pgcount, prot, lvl,
+ ptep, gfp, mapped);
/*
* Synchronise all PTE updates for the new mapping before there's
* a chance for anything to kick off a table walk for the new iova.
@@ -486,6 +499,13 @@ static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova,
return ret;
}

+static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova,
+ phys_addr_t paddr, size_t size, int iommu_prot, gfp_t gfp)
+{
+ return arm_lpae_map_pages(ops, iova, paddr, size, 1, iommu_prot, gfp,
+ NULL);
+}
+
static void __arm_lpae_free_pgtable(struct arm_lpae_io_pgtable *data, int lvl,
arm_lpae_iopte *ptep)
{
@@ -782,6 +802,7 @@ arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)

data->iop.ops = (struct io_pgtable_ops) {
.map = arm_lpae_map,
+ .map_pages = arm_lpae_map_pages,
.unmap = arm_lpae_unmap,
.unmap_pages = arm_lpae_unmap_pages,
.iova_to_phys = arm_lpae_iova_to_phys,