[PATCH] iommu/qcom: Use domain rather than dev as tlb cookie

Rob Clark
2020-07-20T15:51:48Z

From: Rob Clark <robdclark@chromium.org>

The device may be torn down, but the domain should still be valid. Lets
use that as the tlb flush ops cookie.

Fixes a problem reported in [1]

[1] https://lkml.org/lkml/2020/7/20/104

Signed-off-by: Rob Clark <robdclark@chromium.org>
---
Note I don't have a good setup to test this atm, but I think it should
work.

drivers/iommu/qcom_iommu.c | 37 +++++++++++++++++--------------------
1 file changed, 17 insertions(+), 20 deletions(-)

diff --git a/drivers/iommu/qcom_iommu.c b/drivers/iommu/qcom_iommu.c
index c3e1fbd1988c..d176df569af8 100644
--- a/drivers/iommu/qcom_iommu.c
+++ b/drivers/iommu/qcom_iommu.c
@@ -65,6 +65,7 @@ struct qcom_iommu_domain {
struct mutex init_mutex; /* Protects iommu pointer */
struct iommu_domain domain;
struct qcom_iommu_dev *iommu;
+ struct iommu_fwspec *fwspec;
};

static struct qcom_iommu_domain *to_qcom_iommu_domain(struct iommu_domain *dom)
@@ -84,9 +85,9 @@ static struct qcom_iommu_dev * to_iommu(struct device *dev)
return dev_iommu_priv_get(dev);
}

-static struct qcom_iommu_ctx * to_ctx(struct device *dev, unsigned asid)
+static struct qcom_iommu_ctx * to_ctx(struct qcom_iommu_domain *d, unsigned asid)
{
- struct qcom_iommu_dev *qcom_iommu = to_iommu(dev);
+ struct qcom_iommu_dev *qcom_iommu = d->iommu;
if (!qcom_iommu)
return NULL;
return qcom_iommu->ctxs[asid - 1];
@@ -118,14 +119,12 @@ iommu_readq(struct qcom_iommu_ctx *ctx, unsigned reg)

static void qcom_iommu_tlb_sync(void *cookie)
{
- struct iommu_fwspec *fwspec;
- struct device *dev = cookie;
+ struct qcom_iommu_domain *qcom_domain = cookie;
+ struct iommu_fwspec *fwspec = qcom_domain->fwspec;
unsigned i;

- fwspec = dev_iommu_fwspec_get(dev);
-
for (i = 0; i < fwspec->num_ids; i++) {
- struct qcom_iommu_ctx *ctx = to_ctx(dev, fwspec->ids[i]);
+ struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
unsigned int val, ret;

iommu_writel(ctx, ARM_SMMU_CB_TLBSYNC, 0);
@@ -139,14 +138,12 @@ static void qcom_iommu_tlb_sync(void *cookie)

static void qcom_iommu_tlb_inv_context(void *cookie)
{
- struct device *dev = cookie;
- struct iommu_fwspec *fwspec;
+ struct qcom_iommu_domain *qcom_domain = cookie;
+ struct iommu_fwspec *fwspec = qcom_domain->fwspec;
unsigned i;

- fwspec = dev_iommu_fwspec_get(dev);
-
for (i = 0; i < fwspec->num_ids; i++) {
- struct qcom_iommu_ctx *ctx = to_ctx(dev, fwspec->ids[i]);
+ struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
iommu_writel(ctx, ARM_SMMU_CB_S1_TLBIASID, ctx->asid);
}

@@ -156,16 +153,14 @@ static void qcom_iommu_tlb_inv_context(void *cookie)
static void qcom_iommu_tlb_inv_range_nosync(unsigned long iova, size_t size,
size_t granule, bool leaf, void *cookie)
{
- struct device *dev = cookie;
- struct iommu_fwspec *fwspec;
+ struct qcom_iommu_domain *qcom_domain = cookie;
+ struct iommu_fwspec *fwspec = qcom_domain->fwspec;
unsigned i, reg;

reg = leaf ? ARM_SMMU_CB_S1_TLBIVAL : ARM_SMMU_CB_S1_TLBIVA;

- fwspec = dev_iommu_fwspec_get(dev);
-
for (i = 0; i < fwspec->num_ids; i++) {
- struct qcom_iommu_ctx *ctx = to_ctx(dev, fwspec->ids[i]);
+ struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
size_t s = size;

iova = (iova >> 12) << 12;
@@ -256,7 +251,9 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain,
};

qcom_domain->iommu = qcom_iommu;
- pgtbl_ops = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &pgtbl_cfg, dev);
+ qcom_domain->fwspec = fwspec;
+
+ pgtbl_ops = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &pgtbl_cfg, qcom_domain);
if (!pgtbl_ops) {
dev_err(qcom_iommu->dev, "failed to allocate pagetable ops\n");
ret = -ENOMEM;
@@ -269,7 +266,7 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain,
domain->geometry.force_aperture = true;

for (i = 0; i < fwspec->num_ids; i++) {
- struct qcom_iommu_ctx *ctx = to_ctx(dev, fwspec->ids[i]);
+ struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);

if (!ctx->secure_init) {
ret = qcom_scm_restore_sec_cfg(qcom_iommu->sec_id, ctx->asid);
@@ -419,7 +416,7 @@ static void qcom_iommu_detach_dev(struct iommu_domain *domain, struct device *de

pm_runtime_get_sync(qcom_iommu->dev);
for (i = 0; i < fwspec->num_ids; i++) {
- struct qcom_iommu_ctx *ctx = to_ctx(dev, fwspec->ids[i]);
+ struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);

/* Disable the context bank: */
iommu_writel(ctx, ARM_SMMU_CB_SCTLR, 0);
--
2.26.2