[PATCH kernel v3 03/22] powerpc/mm/iommu: Make mm_iommu_new() fail on existing regions

Alexey Kardashevskiy aik at ozlabs.ru
Tue Nov 13 19:28:04 AEDT 2018


Since we are going to have 2 different preregistering helpers, let's
make it clear that mm_iommu_new() is only for the normal memory
(i.e.not device memory) and for existing areas mm_iommu_get() should be
used instead.

This removes the check for exact match as the check for overlap is
enough now.

Signed-off-by: Alexey Kardashevskiy <aik at ozlabs.ru>
---
Changes:
v2:
* remove the exact match check
---
 arch/powerpc/mm/mmu_context_iommu.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/arch/powerpc/mm/mmu_context_iommu.c b/arch/powerpc/mm/mmu_context_iommu.c
index babc6ad..580d89e 100644
--- a/arch/powerpc/mm/mmu_context_iommu.c
+++ b/arch/powerpc/mm/mmu_context_iommu.c
@@ -102,12 +102,6 @@ long mm_iommu_new(struct mm_struct *mm, unsigned long ua, unsigned long entries,
 
 	list_for_each_entry_rcu(mem, &mm->context.iommu_group_mem_list,
 			next) {
-		if ((mem->ua == ua) && (mem->entries == entries)) {
-			++mem->used;
-			*pmem = mem;
-			goto unlock_exit;
-		}
-
 		/* Overlap? */
 		if ((mem->ua < (ua + (entries << PAGE_SHIFT))) &&
 				(ua < (mem->ua +
-- 
2.17.1



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