[RFC PATCH v2 37/58] iommu/io-pgtable: Generalize walker interface
Mostafa Saleh
smostafa at google.com
Thu Dec 12 10:04:01 PST 2024
Add a common struct for walker, which has a callback visitor
with HW agnostic info (phys addr + size).
Add size to walker so it can walk a range of IOVAs.
Also, add a cookie for the arm walker.
Signed-off-by: Mostafa Saleh <smostafa at google.com>
---
drivers/gpu/drm/msm/msm_iommu.c | 5 +++-
drivers/iommu/io-pgtable-arm-common.c | 35 ++++++++++++++++++---------
include/linux/io-pgtable-arm.h | 2 +-
include/linux/io-pgtable.h | 18 ++++++++++++--
4 files changed, 45 insertions(+), 15 deletions(-)
diff --git a/drivers/gpu/drm/msm/msm_iommu.c b/drivers/gpu/drm/msm/msm_iommu.c
index 3e692818ba1f..8516861dd626 100644
--- a/drivers/gpu/drm/msm/msm_iommu.c
+++ b/drivers/gpu/drm/msm/msm_iommu.c
@@ -200,6 +200,9 @@ msm_iommu_pagetable_walk(struct msm_mmu *mmu, unsigned long iova, uint64_t ptes[
{
struct msm_iommu_pagetable *pagetable;
struct arm_lpae_io_pgtable_walk_data wd = {};
+ struct io_pgtable_walk_common walker = {
+ .data = &wd,
+ };
if (mmu->type != MSM_MMU_IOMMU_PAGETABLE)
return -EINVAL;
@@ -209,7 +212,7 @@ msm_iommu_pagetable_walk(struct msm_mmu *mmu, unsigned long iova, uint64_t ptes[
if (!pagetable->pgtbl_ops->pgtable_walk)
return -EINVAL;
- pagetable->pgtbl_ops->pgtable_walk(pagetable->pgtbl_ops, iova, &wd);
+ pagetable->pgtbl_ops->pgtable_walk(pagetable->pgtbl_ops, iova, 1, &walker);
for (int i = 0; i < ARRAY_SIZE(wd.ptes); i++)
ptes[i] = wd.ptes[i];
diff --git a/drivers/iommu/io-pgtable-arm-common.c b/drivers/iommu/io-pgtable-arm-common.c
index 21ee8ff7c881..4fc0b03494e3 100644
--- a/drivers/iommu/io-pgtable-arm-common.c
+++ b/drivers/iommu/io-pgtable-arm-common.c
@@ -481,7 +481,8 @@ struct iova_to_phys_data {
static int visit_iova_to_phys(struct io_pgtable_walk_data *walk_data, int lvl,
arm_lpae_iopte *ptep, size_t size)
{
- struct iova_to_phys_data *data = walk_data->data;
+ struct io_pgtable_walk_common *walker = walk_data->data;
+ struct iova_to_phys_data *data = walker->data;
data->pte = *ptep;
data->lvl = lvl;
return 0;
@@ -492,8 +493,11 @@ static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
{
struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
struct iova_to_phys_data d;
- struct io_pgtable_walk_data walk_data = {
+ struct io_pgtable_walk_common walker = {
.data = &d,
+ };
+ struct io_pgtable_walk_data walk_data = {
+ .data = &walker,
.visit = visit_iova_to_phys,
.addr = iova,
.end = iova + 1,
@@ -511,23 +515,25 @@ static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
static int visit_pgtable_walk(struct io_pgtable_walk_data *walk_data, int lvl,
arm_lpae_iopte *ptep, size_t size)
{
- struct arm_lpae_io_pgtable_walk_data *data = walk_data->data;
- data->ptes[data->level++] = *ptep;
+ struct io_pgtable_walk_common *walker = walk_data->data;
+ struct arm_lpae_io_pgtable_walk_data *data = walker->data;
+
+ data->ptes[lvl] = *ptep;
+ data->level = lvl + 1;
return 0;
}
-static int arm_lpae_pgtable_walk(struct io_pgtable_ops *ops, unsigned long iova, void *wd)
+static int arm_lpae_pgtable_walk(struct io_pgtable_ops *ops, unsigned long iova,
+ size_t size, struct io_pgtable_walk_common *walker)
{
struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
struct io_pgtable_walk_data walk_data = {
- .data = wd,
+ .data = walker,
.visit = visit_pgtable_walk,
.addr = iova,
- .end = iova + 1,
+ .end = iova + size,
};
- ((struct arm_lpae_io_pgtable_walk_data *)wd)->level = 0;
-
return __arm_lpae_iopte_walk(data, &walk_data, data->pgd, data->start_level);
}
@@ -537,6 +543,7 @@ static int io_pgtable_visit(struct arm_lpae_io_pgtable *data,
{
struct io_pgtable *iop = &data->iop;
arm_lpae_iopte pte = READ_ONCE(*ptep);
+ struct io_pgtable_walk_common *walker = walk_data->data;
size_t size = ARM_LPAE_BLOCK_SIZE(lvl, data);
int ret = walk_data->visit(walk_data, lvl, ptep, size);
@@ -544,6 +551,8 @@ static int io_pgtable_visit(struct arm_lpae_io_pgtable *data,
return ret;
if (iopte_leaf(pte, lvl, iop->fmt)) {
+ if (walker->visit_leaf)
+ walker->visit_leaf(iopte_to_paddr(pte, data), size, walker, ptep);
walk_data->addr += size;
return 0;
}
@@ -585,7 +594,8 @@ static int __arm_lpae_iopte_walk(struct arm_lpae_io_pgtable *data,
static int visit_dirty(struct io_pgtable_walk_data *walk_data, int lvl,
arm_lpae_iopte *ptep, size_t size)
{
- struct iommu_dirty_bitmap *dirty = walk_data->data;
+ struct io_pgtable_walk_common *walker = walk_data->data;
+ struct iommu_dirty_bitmap *dirty = walker->data;
if (!iopte_leaf(*ptep, lvl, walk_data->iop->fmt))
return 0;
@@ -606,9 +616,12 @@ static int arm_lpae_read_and_clear_dirty(struct io_pgtable_ops *ops,
{
struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
struct io_pgtable_cfg *cfg = &data->iop.cfg;
+ struct io_pgtable_walk_common walker = {
+ .data = dirty,
+ };
struct io_pgtable_walk_data walk_data = {
.iop = &data->iop,
- .data = dirty,
+ .data = &walker,
.visit = visit_dirty,
.flags = flags,
.addr = iova,
diff --git a/include/linux/io-pgtable-arm.h b/include/linux/io-pgtable-arm.h
index 88922314157d..9e5878c37d78 100644
--- a/include/linux/io-pgtable-arm.h
+++ b/include/linux/io-pgtable-arm.h
@@ -18,7 +18,7 @@ struct arm_lpae_io_pgtable {
struct io_pgtable_walk_data {
struct io_pgtable *iop;
- void *data;
+ struct io_pgtable_walk_common *data;
int (*visit)(struct io_pgtable_walk_data *walk_data, int lvl,
arm_lpae_iopte *ptep, size_t size);
unsigned long flags;
diff --git a/include/linux/io-pgtable.h b/include/linux/io-pgtable.h
index f789234c703b..da50e17b0177 100644
--- a/include/linux/io-pgtable.h
+++ b/include/linux/io-pgtable.h
@@ -185,12 +185,25 @@ struct io_pgtable_cfg {
*
* @ptes: The recorded PTE values from the walk
* @level: The level of the last PTE
+ * @cookie: Cookie set by caller to identify it
*
* @level also specifies the last valid index in @ptes
*/
struct arm_lpae_io_pgtable_walk_data {
u64 ptes[4];
int level;
+ void *cookie;
+};
+
+/**
+ * struct io_pgtable_walk_common - common information from a pgtable walk
+ * @visit_leaf: callback for each leaf providing it's physical address and size
+ */
+struct io_pgtable_walk_common {
+ void (*visit_leaf)(phys_addr_t paddr, size_t size,
+ struct io_pgtable_walk_common *data,
+ void *wd);
+ void *data; /* pointer to walk data as arm_lpae_io_pgtable_walk_data*/
};
/**
@@ -199,7 +212,7 @@ struct arm_lpae_io_pgtable_walk_data {
* @map_pages: Map a physically contiguous range of pages of the same size.
* @unmap_pages: Unmap a range of virtually contiguous pages of the same size.
* @iova_to_phys: Translate iova to physical address.
- * @pgtable_walk: (optional) Perform a page table walk for a given iova.
+ * @pgtable_walk: (optional) Perform a page table walk for a given iova and size.
*
* These functions map directly onto the iommu_ops member functions with
* the same names.
@@ -213,7 +226,8 @@ struct io_pgtable_ops {
struct iommu_iotlb_gather *gather);
phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
unsigned long iova);
- int (*pgtable_walk)(struct io_pgtable_ops *ops, unsigned long iova, void *wd);
+ int (*pgtable_walk)(struct io_pgtable_ops *ops, unsigned long iova,
+ size_t size, struct io_pgtable_walk_common *walker);
int (*read_and_clear_dirty)(struct io_pgtable_ops *ops,
unsigned long iova, size_t size,
unsigned long flags,
--
2.47.0.338.g60cca15819-goog
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