[PATCH v5 1/6] iommu/msm: Fix error-out routine in msm_iommu_attach_dev()

Nicolin Chen
2022-09-22T08:54:12Z

The error-out routine is missing all the reverting pieces for the iop and
attached-ctx allocations. And clock enable/disable is unbalanced too.

Fix it by adding __disable_clocks() and calling msm_iommu_detach_dev() at
the end of the msm_iommu_attach_dev() if "ret" is non-zero. Also set the
master->num to 0 in the detach_dev() since attach_dev() would check it.

Fixes: 109bd48ea2e1 ("iommu/msm: Add DT adaptation")
Cc: stable@vger.kernel.org
Cc: Sricharan R <sricharan@codeaurora.org>
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Konrad Dybcio <konrad.dybcio@somainline.org>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
drivers/iommu/msm_iommu.c | 59 +++++++++++++++++++++------------------
1 file changed, 32 insertions(+), 27 deletions(-)

diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c
index 6a24aa804ea3..14df722f0060 100644
--- a/drivers/iommu/msm_iommu.c
+++ b/drivers/iommu/msm_iommu.c
@@ -394,6 +394,34 @@ static struct iommu_device *msm_iommu_probe_device(struct device *dev)
return &iommu->iommu;
}

+static void msm_iommu_detach_dev(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct msm_priv *priv = to_msm_priv(domain);
+ unsigned long flags;
+ struct msm_iommu_dev *iommu;
+ struct msm_iommu_ctx_dev *master;
+ int ret;
+
+ free_io_pgtable_ops(priv->iop);
+
+ spin_lock_irqsave(&msm_iommu_lock, flags);
+ list_for_each_entry(iommu, &priv->list_attached, dom_node) {
+ ret = __enable_clocks(iommu);
+ if (ret)
+ goto fail;
+
+ list_for_each_entry(master, &iommu->ctx_list, list) {
+ msm_iommu_free_ctx(iommu->context_map, master->num);
+ __reset_context(iommu->base, master->num);
+ master->num = 0;
+ }
+ __disable_clocks(iommu);
+ }
+fail:
+ spin_unlock_irqrestore(&msm_iommu_lock, flags);
+}
+
static int msm_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
{
int ret = 0;
@@ -418,6 +446,7 @@ static int msm_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
list_for_each_entry(master, &iommu->ctx_list, list) {
if (master->num) {
dev_err(dev, "domain already attached");
+ __disable_clocks(iommu);
ret = -EEXIST;
goto fail;
}
@@ -425,6 +454,7 @@ static int msm_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
msm_iommu_alloc_ctx(iommu->context_map,
0, iommu->ncb);
if (IS_ERR_VALUE(master->num)) {
+ __disable_clocks(iommu);
ret = -ENODEV;
goto fail;
}
@@ -439,37 +469,12 @@ static int msm_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)

fail:
spin_unlock_irqrestore(&msm_iommu_lock, flags);
+ if (ret)
+ msm_iommu_detach_dev(domain, dev);

return ret;
}

-static void msm_iommu_detach_dev(struct iommu_domain *domain,
- struct device *dev)
-{
- struct msm_priv *priv = to_msm_priv(domain);
- unsigned long flags;
- struct msm_iommu_dev *iommu;
- struct msm_iommu_ctx_dev *master;
- int ret;
-
- free_io_pgtable_ops(priv->iop);
-
- spin_lock_irqsave(&msm_iommu_lock, flags);
- list_for_each_entry(iommu, &priv->list_attached, dom_node) {
- ret = __enable_clocks(iommu);
- if (ret)
- goto fail;
-
- list_for_each_entry(master, &iommu->ctx_list, list) {
- msm_iommu_free_ctx(iommu->context_map, master->num);
- __reset_context(iommu->base, master->num);
- }
- __disable_clocks(iommu);
- }
-fail:
- spin_unlock_irqrestore(&msm_iommu_lock, flags);
-}
-
static int msm_iommu_map(struct iommu_domain *domain, unsigned long iova,
phys_addr_t pa, size_t len, int prot, gfp_t gfp)
{
--
2.17.1