swiotlb: Move alloc_size to swiotlb_find_slots

Rename find_slots to swiotlb_find_slots and move the maintenance of
alloc_size to it for better code reusability later.

Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 04319dd22d28fba4bb1139739bd7ae32ec088604..0116a630dc13c4c2d6b4c8480c464be8a41c2c38 100644 (file)
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -430,8 +430,8 @@ static unsigned int wrap_index(struct io_tlb_mem *mem, unsigned int index)
  * Find a suitable number of IO TLB entries size that will fit this request and
  * allocate a buffer from that IO TLB pool.
  */
-static int find_slots(struct device *dev, phys_addr_t orig_addr,
-               size_t alloc_size)
+static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
+                             size_t alloc_size)
 {
        struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
        unsigned long boundary_mask = dma_get_seg_boundary(dev);
@@ -442,6 +442,7 @@ static int find_slots(struct device *dev, phys_addr_t orig_addr,
                dma_get_min_align_mask(dev) & ~(IO_TLB_SIZE - 1);
        unsigned int nslots = nr_slots(alloc_size), stride;
        unsigned int index, wrap, count = 0, i;
+       unsigned int offset = swiotlb_align_offset(dev, orig_addr);
        unsigned long flags;
 
        BUG_ON(!nslots);
@@ -486,8 +487,11 @@ not_found:
        return -1;
 
 found:
-       for (i = index; i < index + nslots; i++)
+       for (i = index; i < index + nslots; i++) {
                mem->slots[i].list = 0;
+               mem->slots[i].alloc_size =
+                       alloc_size - (offset + ((i - index) << IO_TLB_SHIFT));
+       }
        for (i = index - 1;
             io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 &&
             mem->slots[i].list; i--)
@@ -528,7 +532,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
                return (phys_addr_t)DMA_MAPPING_ERROR;
        }
 
-       index = find_slots(dev, orig_addr, alloc_size + offset);
+       index = swiotlb_find_slots(dev, orig_addr, alloc_size + offset);
        if (index == -1) {
                if (!(attrs & DMA_ATTR_NO_WARN))
                        dev_warn_ratelimited(dev,
@@ -542,11 +546,8 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
         * This is needed when we sync the memory.  Then we sync the buffer if
         * needed.
         */
-       for (i = 0; i < nr_slots(alloc_size + offset); i++) {
+       for (i = 0; i < nr_slots(alloc_size + offset); i++)
                mem->slots[index + i].orig_addr = slot_addr(orig_addr, i);
-               mem->slots[index + i].alloc_size =
-                       alloc_size - (i << IO_TLB_SHIFT);
-       }
        tlb_addr = slot_addr(mem->start, index) + offset;
        if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
            (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))