Similarly to the root/context pgtables, the IOMMU driver also does
phys_to_virt when walking the domain pgtables. To make this work
properly the physical memory needs to be mapped in at the correct place
in the direct map. Register a memory device to support this.
The alternative would be to wrap all of the phys_to_virt functions in
something which is pkernfs aware.
---
fs/pkernfs/iommu.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)
diff --git a/fs/pkernfs/iommu.c b/fs/pkernfs/iommu.c
index 5d0b256e7dd8..073b9dd48237 100644
--- a/fs/pkernfs/iommu.c
+++ b/fs/pkernfs/iommu.c
@@ -9,6 +9,7 @@ void pkernfs_get_region_for_ppts(struct file *ppts, struct pkernfs_region *pkern
struct pkernfs_inode *pkernfs_inode;
unsigned long *mappings_block_vaddr;
unsigned long inode_idx;
+ int rc;
/*
* For a pkernfs region block, the "mappings_block" field is still
@@ -22,7 +23,20 @@ void pkernfs_get_region_for_ppts(struct file *ppts, struct pkernfs_region *pkern
mappings_block_vaddr = (unsigned long *)pkernfs_addr_for_block(NULL,
pkernfs_inode->mappings_block);
set_bit(0, mappings_block_vaddr);
- pkernfs_region->vaddr = mappings_block_vaddr;
+
+ dev_set_name(&pkernfs_region->dev, "vfio-ppt-%s", pkernfs_inode->filename);
+ rc = device_register(&pkernfs_region->dev);
+ if (rc)
+ pr_err("device_register failed: %i\n", rc);
+
+ pkernfs_region->pgmap.range.start = pkernfs_base +
+ (pkernfs_inode->mappings_block * PMD_SIZE);
+ pkernfs_region->pgmap.range.end =
+ pkernfs_region->pgmap.range.start + PMD_SIZE - 1;
+ pkernfs_region->pgmap.nr_range = 1;
+ pkernfs_region->pgmap.type = MEMORY_DEVICE_GENERIC;
+ pkernfs_region->vaddr =
+ devm_memremap_pages(&pkernfs_region->dev, &pkernfs_region->pgmap);
pkernfs_region->paddr = pkernfs_base + (pkernfs_inode->mappings_block * (2 << 20));
}
void pkernfs_alloc_iommu_root_pgtables(struct pkernfs_region *pkernfs_region)
--
2.40.1
