1 files changed, 30 insertions, 90 deletions

diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index 3657da8ebbc3..98a7a4450e02 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -89,10 +89,7 @@ static unsigned int io_tlb_index;
  * We need to save away the original address corresponding to a mapped entry
  * for the sync operations.
  */
-static struct swiotlb_phys_addr {
-        struct page *page;
-        unsigned int offset;
-} *io_tlb_orig_addr;
+static phys_addr_t *io_tlb_orig_addr;
 
 /*
  * Protect the above data structures in the map and unmap calls
@@ -204,7 +201,7 @@ swiotlb_init_with_default_size(size_t default_size)
         for (i = 0; i < io_tlb_nslabs; i++)
                 io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
         io_tlb_index = 0;
-        io_tlb_orig_addr = alloc_bootmem(io_tlb_nslabs * sizeof(struct swiotlb_phys_addr));
+        io_tlb_orig_addr = alloc_bootmem(io_tlb_nslabs * sizeof(phys_addr_t));
 
         /*
          * Get the overflow emergency buffer
@@ -278,12 +275,14 @@ swiotlb_late_init_with_default_size(size_t default_size)
                 io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
         io_tlb_index = 0;
 
-        io_tlb_orig_addr = (struct swiotlb_phys_addr *)__get_free_pages(GFP_KERNEL,
-                                   get_order(io_tlb_nslabs * sizeof(struct swiotlb_phys_addr)));
+        io_tlb_orig_addr = (phys_addr_t *)
+                __get_free_pages(GFP_KERNEL,
+                                 get_order(io_tlb_nslabs *
+                                           sizeof(phys_addr_t)));
         if (!io_tlb_orig_addr)
                 goto cleanup3;
 
-        memset(io_tlb_orig_addr, 0, io_tlb_nslabs * sizeof(struct swiotlb_phys_addr));
+        memset(io_tlb_orig_addr, 0, io_tlb_nslabs * sizeof(phys_addr_t));
 
         /*
          * Get the overflow emergency buffer
@@ -298,8 +297,8 @@ swiotlb_late_init_with_default_size(size_t default_size)
         return 0;
 
 cleanup4:
-        free_pages((unsigned long)io_tlb_orig_addr, get_order(io_tlb_nslabs *
-                                                              sizeof(char *)));
+        free_pages((unsigned long)io_tlb_orig_addr,
+                   get_order(io_tlb_nslabs * sizeof(phys_addr_t)));
         io_tlb_orig_addr = NULL;
 cleanup3:
         free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
@@ -330,59 +329,11 @@ static int is_swiotlb_buffer(char *addr)
         return addr >= io_tlb_start && addr < io_tlb_end;
 }
 
-static struct swiotlb_phys_addr swiotlb_bus_to_phys_addr(char *dma_addr)
-{
-        int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
-        struct swiotlb_phys_addr buffer = io_tlb_orig_addr[index];
-        buffer.offset += (long)dma_addr & ((1 << IO_TLB_SHIFT) - 1);
-        buffer.page += buffer.offset >> PAGE_SHIFT;
-        buffer.offset &= PAGE_SIZE - 1;
-        return buffer;
-}
-
-static void
-__sync_single(struct swiotlb_phys_addr buffer, char *dma_addr, size_t size, int dir)
-{
-        if (PageHighMem(buffer.page)) {
-                size_t len, bytes;
-                char *dev, *host, *kmp;
-
-                len = size;
-                while (len != 0) {
-                        unsigned long flags;
-
-                        bytes = len;
-                        if ((bytes + buffer.offset) > PAGE_SIZE)
-                                bytes = PAGE_SIZE - buffer.offset;
-                        local_irq_save(flags); /* protects KM_BOUNCE_READ */
-                        kmp  = kmap_atomic(buffer.page, KM_BOUNCE_READ);
-                        dev  = dma_addr + size - len;
-                        host = kmp + buffer.offset;
-                        if (dir == DMA_FROM_DEVICE)
-                                memcpy(host, dev, bytes);
-                        else
-                                memcpy(dev, host, bytes);
-                        kunmap_atomic(kmp, KM_BOUNCE_READ);
-                        local_irq_restore(flags);
-                        len -= bytes;
-                        buffer.page++;
-                        buffer.offset = 0;
-                }
-        } else {
-                void *v = page_address(buffer.page) + buffer.offset;
-
-                if (dir == DMA_TO_DEVICE)
-                        memcpy(dma_addr, v, size);
-                else
-                        memcpy(v, dma_addr, size);
-        }
-}
-
 /*
  * Allocates bounce buffer and returns its kernel virtual address.
  */
 static void *
-map_single(struct device *hwdev, struct swiotlb_phys_addr buffer, size_t size, int dir)
+map_single(struct device *hwdev, phys_addr_t phys, size_t size, int dir)
 {
         unsigned long flags;
         char *dma_addr;
@@ -392,7 +343,6 @@ map_single(struct device *hwdev, struct swiotlb_phys_addr buffer, size_t size, i
         unsigned long mask;
         unsigned long offset_slots;
         unsigned long max_slots;
-        struct swiotlb_phys_addr slot_buf;
 
         mask = dma_get_seg_boundary(hwdev);
         start_dma_addr = swiotlb_virt_to_bus(hwdev, io_tlb_start) & mask;
@@ -477,15 +427,10 @@ found:
          * This is needed when we sync the memory.  Then we sync the buffer if
          * needed.
          */
-        slot_buf = buffer;
-        for (i = 0; i < nslots; i++) {
-                slot_buf.page += slot_buf.offset >> PAGE_SHIFT;
-                slot_buf.offset &= PAGE_SIZE - 1;
-                io_tlb_orig_addr[index+i] = slot_buf;
-                slot_buf.offset += 1 << IO_TLB_SHIFT;
-        }
+        for (i = 0; i < nslots; i++)
+                io_tlb_orig_addr[index+i] = phys + (i << IO_TLB_SHIFT);
         if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
-                __sync_single(buffer, dma_addr, size, DMA_TO_DEVICE);
+                memcpy(dma_addr, phys_to_virt(phys), size);
 
         return dma_addr;
 }
@@ -499,17 +444,17 @@ unmap_single(struct device *hwdev, char *dma_addr, size_t size, int dir)
         unsigned long flags;
         int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
         int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
-        struct swiotlb_phys_addr buffer = swiotlb_bus_to_phys_addr(dma_addr);
+        phys_addr_t phys = io_tlb_orig_addr[index];
 
         /*
          * First, sync the memory before unmapping the entry
          */
-        if ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL))
+        if (phys && ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL)))
                 /*
                  * bounce... copy the data back into the original buffer * and
                  * delete the bounce buffer.
                  */
-                __sync_single(buffer, dma_addr, size, DMA_FROM_DEVICE);
+                memcpy(phys_to_virt(phys), dma_addr, size);
 
         /*
          * Return the buffer to the free list by setting the corresponding
@@ -541,18 +486,21 @@ static void
 sync_single(struct device *hwdev, char *dma_addr, size_t size,
             int dir, int target)
 {
-        struct swiotlb_phys_addr buffer = swiotlb_bus_to_phys_addr(dma_addr);
+        int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
+        phys_addr_t phys = io_tlb_orig_addr[index];
+
+        phys += ((unsigned long)dma_addr & ((1 << IO_TLB_SHIFT) - 1));
 
         switch (target) {
         case SYNC_FOR_CPU:
                 if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
-                        __sync_single(buffer, dma_addr, size, DMA_FROM_DEVICE);
+                        memcpy(phys_to_virt(phys), dma_addr, size);
                 else
                         BUG_ON(dir != DMA_TO_DEVICE);
                 break;
         case SYNC_FOR_DEVICE:
                 if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
-                        __sync_single(buffer, dma_addr, size, DMA_TO_DEVICE);
+                        memcpy(dma_addr, phys_to_virt(phys), size);
                 else
                         BUG_ON(dir != DMA_FROM_DEVICE);
                 break;
@@ -591,10 +539,7 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size,
                  * swiotlb_map_single(), which will grab memory from
                  * the lowest available address range.
                  */
-                struct swiotlb_phys_addr buffer;
-                buffer.page = virt_to_page(NULL);
-                buffer.offset = 0;
-                ret = map_single(hwdev, buffer, size, DMA_FROM_DEVICE);
+                ret = map_single(hwdev, 0, size, DMA_FROM_DEVICE);
                 if (!ret)
                         return NULL;
         }
@@ -662,7 +607,6 @@ swiotlb_map_single_attrs(struct device *hwdev, void *ptr, size_t size,
 {
         dma_addr_t dev_addr = swiotlb_virt_to_bus(hwdev, ptr);
         void *map;
-        struct swiotlb_phys_addr buffer;
 
         BUG_ON(dir == DMA_NONE);
         /*
@@ -677,9 +621,7 @@ swiotlb_map_single_attrs(struct device *hwdev, void *ptr, size_t size,
         /*
          * Oh well, have to allocate and map a bounce buffer.
          */
-        buffer.page   = virt_to_page(ptr);
-        buffer.offset = (unsigned long)ptr & ~PAGE_MASK;
-        map = map_single(hwdev, buffer, size, dir);
+        map = map_single(hwdev, virt_to_phys(ptr), size, dir);
         if (!map) {
                 swiotlb_full(hwdev, size, dir, 1);
                 map = io_tlb_overflow_buffer;
@@ -824,20 +766,18 @@ swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
                      int dir, struct dma_attrs *attrs)
 {
         struct scatterlist *sg;
-        struct swiotlb_phys_addr buffer;
-        dma_addr_t dev_addr;
         int i;
 
         BUG_ON(dir == DMA_NONE);
 
         for_each_sg(sgl, sg, nelems, i) {
-                dev_addr = swiotlb_sg_to_bus(hwdev, sg);
-                if (range_needs_mapping(sg_virt(sg), sg->length) ||
+                void *addr = sg_virt(sg);
+                dma_addr_t dev_addr = swiotlb_virt_to_bus(hwdev, addr);
+
+                if (range_needs_mapping(addr, sg->length) ||
                     address_needs_mapping(hwdev, dev_addr, sg->length)) {
-                        void *map;
-                        buffer.page   = sg_page(sg);
-                        buffer.offset = sg->offset;
-                        map = map_single(hwdev, buffer, sg->length, dir);
+                        void *map = map_single(hwdev, sg_phys(sg),
+                                               sg->length, dir);
                         if (!map) {
                                 /* Don't panic here, we expect map_sg users
                                    to do proper error handling. */