[PATCH v3 15/23] iommu/pages: Move the __GFP_HIGHMEM checks into the common code
From: Jason Gunthorpe <jgg@nvidia.com>
Date: 2025-02-25 21:08:05
Also in:
asahi, linux-iommu, linux-patches, linux-riscv, linux-rockchip, linux-samsung-soc, linux-sunxi, linux-tegra
Subsystem:
arm smmu drivers, arm/apple machine support, iommu subsystem, the rest · Maintainers:
Will Deacon, Sven Peter, Janne Grunau, Joerg Roedel, Linus Torvalds
The entire allocator API is built around using the kernel virtual address, it is illegal to pass GFP_HIGHMEM in as a GFP flag. Block it in the common code. Remove the duplicated checks from drivers. Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> --- drivers/iommu/io-pgtable-arm.c | 2 -- drivers/iommu/io-pgtable-dart.c | 1 - drivers/iommu/iommu-pages.c | 4 ++++ 3 files changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index 62df2528d020b2..08d0f62abe8a09 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c@@ -267,8 +267,6 @@ static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp, dma_addr_t dma; void *pages; - VM_BUG_ON((gfp & __GFP_HIGHMEM)); - if (cfg->alloc) pages = cfg->alloc(cookie, size, gfp); else
diff --git a/drivers/iommu/io-pgtable-dart.c b/drivers/iommu/io-pgtable-dart.c
index 7efcaea0bd5c86..ebf330e67bfa30 100644
--- a/drivers/iommu/io-pgtable-dart.c
+++ b/drivers/iommu/io-pgtable-dart.c@@ -111,7 +111,6 @@ static void *__dart_alloc_pages(size_t size, gfp_t gfp) { int order = get_order(size); - VM_BUG_ON((gfp & __GFP_HIGHMEM)); return iommu_alloc_pages(gfp, order); }
diff --git a/drivers/iommu/iommu-pages.c b/drivers/iommu/iommu-pages.c
index 3077df642adb1f..a7eed09420a231 100644
--- a/drivers/iommu/iommu-pages.c
+++ b/drivers/iommu/iommu-pages.c@@ -37,6 +37,10 @@ void *iommu_alloc_pages_node(int nid, gfp_t gfp, unsigned int order) const unsigned long pgcnt = 1UL << order; struct folio *folio; + /* This uses page_address() on the memory. */ + if (WARN_ON(gfp & __GFP_HIGHMEM)) + return NULL; + /* * __folio_alloc_node() does not handle NUMA_NO_NODE like * alloc_pages_node() did.
--
2.43.0