Revert "iommu/arm-smmu-v3: Fix soft lockup triggered by arm_smmu_mm_invalidate_range"

BugLink: https://bugs.launchpad.net/bugs/2048966

This reverts commit 9a5dc20.

There are two versions of this patch, one for 6.5 and 6.6.  This is the
6.6 version.  Revert and will apply 6.5 version.

Acked-by: Brad Figg <bfigg@nvidia.com>
Acked-by: Ian May <ian.may@canonical.com>
Signed-off-by: Ian May <ian.may@canonical.com>

Author: ianmay81

drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c

@@ -186,15 +186,6 @@ static void arm_smmu_free_shared_cd(struct arm_smmu_ctx_desc *cd)
 	}
 }
 
-/*
- * Cloned from the MAX_TLBI_OPS in arch/arm64/include/asm/tlbflush.h, this
- * is used as a threshold to replace per-page TLBI commands to issue in the
- * command queue with an address-space TLBI command, when SMMU w/o a range
- * invalidation feature handles too many per-page TLBI commands, which will
- * otherwise result in a soft lockup.
- */
-#define CMDQ_MAX_TLBI_OPS      (1 << (PAGE_SHIFT - 3))
-
 static void arm_smmu_mm_invalidate_range(struct mmu_notifier *mn,
 					 struct mm_struct *mm,
 					 unsigned long start, unsigned long end)
@@ -210,14 +201,6 @@ static void arm_smmu_mm_invalidate_range(struct mmu_notifier *mn,
 	 */
 	size = end - start;
 
-	if (!(smmu_domain->smmu->features & ARM_SMMU_FEAT_RANGE_INV)) {
-		if (size >= CMDQ_MAX_TLBI_OPS * PAGE_SIZE)
-			size = 0;
-	} else {
-		if (size == ULONG_MAX)
-			size = 0;
-	}
-
 	if (!(smmu_domain->smmu->features & ARM_SMMU_FEAT_BTM))
 		arm_smmu_tlb_inv_range_asid(start, size, smmu_mn->cd->asid,
 					    PAGE_SIZE, false, smmu_domain);