From 7998050d1c140100759fc9297023fd73db3f3c93 Mon Sep 17 00:00:00 2001
From: Sven Peter <sven@svenpeter.dev>
Date: Tue, 21 Sep 2021 17:11:02 +0200
Subject: [PATCH] iommu/dart: Remove iommu_flush_ops

apple_dart_tlb_flush_{all,walk} expect to get a struct apple_dart_domain
but instead get a struct iommu_domain right now. This breaks those two
functions and can lead to kernel panics like the one below.
DART can only invalidate the entire TLB and apple_dart_iotlb_sync will
already do just that. There's no need to do that again inside those
two functions. Let's just drop them.

  pci 0000:03:00.0: Removing from iommu group 1
  Unable to handle kernel paging request at virtual address 0000000100000023
  [...]
  Call trace:
   _raw_spin_lock_irqsave+0x54/0xbc
   apple_dart_hw_stream_command.constprop.0+0x2c/0x130
   apple_dart_tlb_flush_all+0x48/0x90
   free_io_pgtable_ops+0x40/0x70
   apple_dart_domain_free+0x2c/0x44
   iommu_group_release+0x68/0xac
   kobject_cleanup+0x4c/0x1fc
   kobject_cleanup+0x14c/0x1fc
   kobject_put+0x64/0x84
   iommu_group_remove_device+0x110/0x180
   iommu_release_device+0x50/0xa0
  [...]

Fixes: 46d1fb072e76b161 ("iommu/dart: Add DART iommu driver")
Reported-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Sven Peter <sven@svenpeter.dev>
---
 drivers/iommu/apple-dart.c | 17 -----------------
 1 file changed, 17 deletions(-)

diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c
index c37fb4790e8a..0a9bb951a4d5 100644
--- a/drivers/iommu/apple-dart.c
+++ b/drivers/iommu/apple-dart.c
@@ -336,22 +336,6 @@ static void apple_dart_iotlb_sync_map(struct iommu_domain *domain,
 	apple_dart_domain_flush_tlb(to_dart_domain(domain));
 }
 
-static void apple_dart_tlb_flush_all(void *cookie)
-{
-	apple_dart_domain_flush_tlb(cookie);
-}
-
-static void apple_dart_tlb_flush_walk(unsigned long iova, size_t size,
-				      size_t granule, void *cookie)
-{
-	apple_dart_domain_flush_tlb(cookie);
-}
-
-static const struct iommu_flush_ops apple_dart_tlb_ops = {
-	.tlb_flush_all = apple_dart_tlb_flush_all,
-	.tlb_flush_walk = apple_dart_tlb_flush_walk,
-};
-
 static phys_addr_t apple_dart_iova_to_phys(struct iommu_domain *domain,
 					   dma_addr_t iova)
 {
@@ -433,7 +417,6 @@ static int apple_dart_finalize_domain(struct iommu_domain *domain,
 		.ias = 32,
 		.oas = 36,
 		.coherent_walk = 1,
-		.tlb = &apple_dart_tlb_ops,
 		.iommu_dev = dart->dev,
 	};
 
-- 
2.25.1

