swiotlb: fix setting ->force_bounce

The swiotlb_init refactor messed up assigning ->force_bounce by doing
it in different places based on what caused the setting of the flag.

Fix this by passing the SWIOTLB_* flags to swiotlb_init_io_tlb_mem
and just setting it there.

Fixes: c6af2aa ("swiotlb: make the swiotlb_init interface more useful")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Nathan Chancellor <nathan@kernel.org>

Author: Christoph Hellwig

kernel/dma/swiotlb.c

@@ -192,7 +192,7 @@ void __init swiotlb_update_mem_attributes(void)
 }
 
 static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start,
-				    unsigned long nslabs, bool late_alloc)
+		unsigned long nslabs, unsigned int flags, bool late_alloc)
 {
 	void *vaddr = phys_to_virt(start);
 	unsigned long bytes = nslabs << IO_TLB_SHIFT, i;
@@ -203,8 +203,7 @@ static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start,
 	mem->index = 0;
 	mem->late_alloc = late_alloc;
 
-	if (swiotlb_force_bounce)
-		mem->force_bounce = true;
+	mem->force_bounce = swiotlb_force_bounce || (flags & SWIOTLB_FORCE);
 
 	spin_lock_init(&mem->lock);
 	for (i = 0; i < mem->nslabs; i++) {
@@ -275,8 +274,7 @@ void __init swiotlb_init_remap(bool addressing_limit, unsigned int flags,
 		panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
 		      __func__, alloc_size, PAGE_SIZE);
 
-	swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, false);
-	mem->force_bounce = flags & SWIOTLB_FORCE;
+	swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, flags, false);
 
 	if (flags & SWIOTLB_VERBOSE)
 		swiotlb_print_info();
@@ -348,7 +346,7 @@ int swiotlb_init_late(size_t size, gfp_t gfp_mask,
 
 	set_memory_decrypted((unsigned long)vstart,
 			     (nslabs << IO_TLB_SHIFT) >> PAGE_SHIFT);
-	swiotlb_init_io_tlb_mem(mem, virt_to_phys(vstart), nslabs, true);
+	swiotlb_init_io_tlb_mem(mem, virt_to_phys(vstart), nslabs, 0, true);
 
 	swiotlb_print_info();
 	return 0;
@@ -835,8 +833,8 @@ static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
 
 		set_memory_decrypted((unsigned long)phys_to_virt(rmem->base),
 				     rmem->size >> PAGE_SHIFT);
-		swiotlb_init_io_tlb_mem(mem, rmem->base, nslabs, false);
-		mem->force_bounce = true;
+		swiotlb_init_io_tlb_mem(mem, rmem->base, nslabs, SWIOTLB_FORCE,
+				false);
 		mem->for_alloc = true;
 
 		rmem->priv = mem;