swiotlb: add a IO_TLB_SIZE define

commit: b5d7ccb7aac3895c2138fe0980a109116ce15eff

Add a new IO_TLB_SIZE define instead open coding it using
IO_TLB_SHIFT all over.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jianxiong Gao <jxgao@google.com>
Tested-by: Jianxiong Gao <jxgao@google.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jianxiong Gao <jxgao@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index fbdc657..5d2dbe7 100644 (file)
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -29,6 +29,7 @@ enum swiotlb_force {
  * controllable.
  */
 #define IO_TLB_SHIFT 11
+#define IO_TLB_SIZE (1 << IO_TLB_SHIFT)
 
 extern void swiotlb_init(int verbose);
 int swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose);

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 781b9dc..fb88c29 100644 (file)
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -475,20 +475,20 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t orig_addr,
 
        tbl_dma_addr &= mask;
 
-       offset_slots = ALIGN(tbl_dma_addr, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
+       offset_slots = ALIGN(tbl_dma_addr, IO_TLB_SIZE) >> IO_TLB_SHIFT;
 
        /*
         * Carefully handle integer overflow which can occur when mask == ~0UL.
         */
        max_slots = mask + 1
-                   ? ALIGN(mask + 1, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT
+                   ? ALIGN(mask + 1, IO_TLB_SIZE) >> IO_TLB_SHIFT
                    : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT);
 
        /*
         * For mappings greater than or equal to a page, we limit the stride
         * (and hence alignment) to a page size.
         */
-       nslots = ALIGN(alloc_size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
+       nslots = ALIGN(alloc_size, IO_TLB_SIZE) >> IO_TLB_SHIFT;
        if (alloc_size >= PAGE_SIZE)
                stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT));
        else
@@ -582,7 +582,7 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
                              enum dma_data_direction dir, unsigned long attrs)
 {
        unsigned long flags;
-       int i, count, nslots = ALIGN(alloc_size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
+       int i, count, nslots = ALIGN(alloc_size, IO_TLB_SIZE) >> IO_TLB_SHIFT;
        int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT;
        phys_addr_t orig_addr = io_tlb_orig_addr[index];
 
@@ -633,7 +633,7 @@ void swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr,
 
        if (orig_addr == INVALID_PHYS_ADDR)
                return;
-       orig_addr += (unsigned long)tlb_addr & ((1 << IO_TLB_SHIFT) - 1);
+       orig_addr += (unsigned long)tlb_addr & (IO_TLB_SIZE - 1);
 
        switch (target) {
        case SYNC_FOR_CPU:
@@ -691,7 +691,7 @@ dma_addr_t swiotlb_map(struct device *dev, phys_addr_t paddr, size_t size,
 
 size_t swiotlb_max_mapping_size(struct device *dev)
 {
-       return ((size_t)1 << IO_TLB_SHIFT) * IO_TLB_SEGSIZE;
+       return ((size_t)IO_TLB_SIZE) * IO_TLB_SEGSIZE;
 }
 
 bool is_swiotlb_active(void)