The arm and arm64 architectures allow a virtual address to be mapped using
a block descriptor (or huge page, as Linux calls it), and the function
mmu_set_ranges_sect() is made available for a test to do just that. But
virt_to_pte_phys() assumes that all virtual addresses are mapped with page
granularity, which can lead to erroneous addresses being returned in the
case of block mappings.
Signed-off-by: Alexandru Elisei <alexandru.elisei@xxxxxxx>
---
lib/arm/mmu.c | 89 +++++++++++++++++++++++++++++++--------------------
1 file changed, 54 insertions(+), 35 deletions(-)
diff --git a/lib/arm/mmu.c b/lib/arm/mmu.c
index e1a72fe4941f..6022e356ddd4 100644
--- a/lib/arm/mmu.c
+++ b/lib/arm/mmu.c
@@ -111,10 +111,61 @@ pteval_t *install_page(pgd_t *pgtable, phys_addr_t phys, void *virt)
__pgprot(PTE_WBWA | PTE_USER));
}
-phys_addr_t virt_to_pte_phys(pgd_t *pgtable, void *mem)
+/*
+ * NOTE: The Arm architecture might require the use of a
+ * break-before-make sequence before making changes to a PTE and
+ * certain conditions are met (see Arm ARM D5-2669 for AArch64 and
+ * B3-1378 for AArch32 for more details).
+ */
+pteval_t *mmu_get_pte(pgd_t *pgtable, uintptr_t vaddr)
{
- return (*get_pte(pgtable, (uintptr_t)mem) & PHYS_MASK & -PAGE_SIZE)
- + ((ulong)mem & (PAGE_SIZE - 1));
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+
+ if (!mmu_enabled())
+ return NULL;
+
+ pgd = pgd_offset(pgtable, vaddr);
+ if (!pgd_valid(*pgd))
+ return NULL;
+
+ pud = pud_offset(pgd, vaddr);
+ if (!pud_valid(*pud))
+ return NULL;
+
+ pmd = pmd_offset(pud, vaddr);
+ if (!pmd_valid(*pmd))
+ return NULL;
+ if (pmd_huge(*pmd))
+ return &pmd_val(*pmd);
+
+ pte = pte_offset(pmd, vaddr);
+ if (!pte_valid(*pte))
+ return NULL;
+
+ return &pte_val(*pte);
+}
+
+phys_addr_t virt_to_pte_phys(pgd_t *pgtable, void *virt)
+{
+ phys_addr_t mask;
+ pteval_t *pteval;
+
+ pteval = mmu_get_pte(pgtable, (uintptr_t)virt);
+ if (!pteval) {
+ install_page(pgtable, (phys_addr_t)(unsigned long)virt, virt);
+ return (phys_addr_t)(unsigned long)virt;
+ }
+
+ if (pmd_huge(__pmd(*pteval)))
+ mask = PMD_MASK;
+ else
+ mask = PAGE_MASK;
+
+ return (*pteval & PHYS_MASK & mask) |
+ ((phys_addr_t)(unsigned long)virt & ~mask);
}
void mmu_set_range_ptes(pgd_t *pgtable, uintptr_t virt_offset,
@@ -231,38 +282,6 @@ unsigned long __phys_to_virt(phys_addr_t addr)
return addr;
}
-/*
- * NOTE: The Arm architecture might require the use of a
- * break-before-make sequence before making changes to a PTE and
- * certain conditions are met (see Arm ARM D5-2669 for AArch64 and
- * B3-1378 for AArch32 for more details).
- */
-pteval_t *mmu_get_pte(pgd_t *pgtable, uintptr_t vaddr)
-{
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
-
- if (!mmu_enabled())
- return NULL;
-
- pgd = pgd_offset(pgtable, vaddr);
- assert(pgd_valid(*pgd));
- pud = pud_offset(pgd, vaddr);
- assert(pud_valid(*pud));
- pmd = pmd_offset(pud, vaddr);
- assert(pmd_valid(*pmd));
-
- if (pmd_huge(*pmd))
- return &pmd_val(*pmd);
-
- pte = pte_offset(pmd, vaddr);
- assert(pte_valid(*pte));
-
- return &pte_val(*pte);
-}
-
void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr)
{
pteval_t *p_pte = mmu_get_pte(pgtable, vaddr);
--
2.37.0
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