From: Robin Murphy <robin.murphy@arm.com>
Date: Fri, 20 Aug 2021 14:14:42 +0100
Subject: iommu/io-pgtable: Abstract iommu_iotlb_gather access
Git-commit: f7403abf5f06f407c50252e003f5fb332325147b
Patch-mainline: v5.15-rc1
References: bsc#1192202
Previously io-pgtable merely passed the iommu_iotlb_gather pointer
through to helpers, but now it has grown its own direct dereference.
This turns out to break the build for !IOMMU_API configs where the
structure only has a dummy definition. It will probably also crash
drivers who don't use the gather mechanism and simply pass in NULL.
Wrap this dereference in a suitable helper which can both be stubbed
out for !IOMMU_API and encapsulate a NULL check otherwise.
Fixes: 7a7c5badf858 ("iommu: Indicate queued flushes via gather data")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/83672ee76f6405c82845a55c148fa836f56fbbc1.1629465282.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/io-pgtable-arm-v7s.c | 2 +-
drivers/iommu/io-pgtable-arm.c | 2 +-
include/linux/iommu.h | 10 ++++++++++
3 files changed, 12 insertions(+), 2 deletions(-)
--- a/drivers/iommu/io-pgtable-arm-v7s.c
+++ b/drivers/iommu/io-pgtable-arm-v7s.c
@@ -700,7 +700,7 @@ static size_t __arm_v7s_unmap(struct arm
ARM_V7S_BLOCK_SIZE(lvl + 1));
ptep = iopte_deref(pte[i], lvl, data);
__arm_v7s_free_table(ptep, lvl + 1, data);
- } else if (!gather->queued) {
+ } else if (!iommu_iotlb_gather_queued(gather)) {
io_pgtable_tlb_add_page(iop, gather, iova, blk_size);
}
iova += blk_size;
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -650,7 +650,7 @@ static size_t __arm_lpae_unmap(struct ar
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 (!gather->queued) {
+ } else if (!iommu_iotlb_gather_queued(gather)) {
io_pgtable_tlb_add_page(iop, gather, iova + i * size, size);
}
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -594,6 +594,11 @@ static inline void iommu_iotlb_gather_ad
iommu_iotlb_gather_add_range(gather, iova, size);
}
+static inline bool iommu_iotlb_gather_queued(struct iommu_iotlb_gather *gather)
+{
+ return gather && gather->queued;
+}
+
/* PCI device grouping function */
extern struct iommu_group *pci_device_group(struct device *dev);
/* Generic device grouping function */
@@ -942,6 +947,11 @@ static inline void iommu_iotlb_gather_ad
{
}
+static inline bool iommu_iotlb_gather_queued(struct iommu_iotlb_gather *gather)
+{
+ return false;
+}
+
static inline void iommu_device_unregister(struct iommu_device *iommu)
{
}