3 files changed, 33 insertions, 4 deletions

diff --git a/arch/sparc64/kernel/iommu.c b/arch/sparc64/kernel/iommu.c
index b781d3d54fb8..756fa24eeefa 100644
--- a/arch/sparc64/kernel/iommu.c
+++ b/arch/sparc64/kernel/iommu.c
@@ -516,9 +516,11 @@ static int dma_4u_map_sg(struct device *dev, struct scatterlist *sglist,
         unsigned long flags, handle, prot, ctx;
         dma_addr_t dma_next = 0, dma_addr;
         unsigned int max_seg_size;
+        unsigned long seg_boundary_size;
         int outcount, incount, i;
         struct strbuf *strbuf;
         struct iommu *iommu;
+        unsigned long base_shift;
 
         BUG_ON(direction == DMA_NONE);
 
@@ -549,8 +551,11 @@ static int dma_4u_map_sg(struct device *dev, struct scatterlist *sglist,
         outs->dma_length = 0;
 
         max_seg_size = dma_get_max_seg_size(dev);
+        seg_boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1,
+                                  IO_PAGE_SIZE) >> IO_PAGE_SHIFT;
+        base_shift = iommu->page_table_map_base >> IO_PAGE_SHIFT;
         for_each_sg(sglist, s, nelems, i) {
-                unsigned long paddr, npages, entry, slen;
+                unsigned long paddr, npages, entry, out_entry = 0, slen;
                 iopte_t *base;
 
                 slen = s->length;
@@ -593,7 +598,9 @@ static int dma_4u_map_sg(struct device *dev, struct scatterlist *sglist,
                          * - allocated dma_addr isn't contiguous to previous allocation
                          */
                         if ((dma_addr != dma_next) ||
-                            (outs->dma_length + s->length > max_seg_size)) {
+                            (outs->dma_length + s->length > max_seg_size) ||
+                            (is_span_boundary(out_entry, base_shift,
+                                              seg_boundary_size, outs, s))) {
                                 /* Can't merge: create a new segment */
                                 segstart = s;
                                 outcount++;
@@ -607,6 +614,7 @@ static int dma_4u_map_sg(struct device *dev, struct scatterlist *sglist,
                         /* This is a new segment, fill entries */
                         outs->dma_address = dma_addr;
                         outs->dma_length = slen;
+                        out_entry = entry;
                 }
 
                 /* Calculate next page pointer for contiguous check */
diff --git a/arch/sparc64/kernel/iommu_common.h b/arch/sparc64/kernel/iommu_common.h
index 0713bd58499c..87ace495d45f 100644
--- a/arch/sparc64/kernel/iommu_common.h
+++ b/arch/sparc64/kernel/iommu_common.h
@@ -12,6 +12,7 @@
 #include <linux/mm.h>
 #include <linux/scatterlist.h>
 #include <linux/device.h>
+#include <linux/iommu-helper.h>
 
 #include <asm/iommu.h>
 #include <asm/scatterlist.h>
@@ -58,6 +59,18 @@ static inline unsigned long calc_npages(struct scatterlist *sglist, int nelems)
         return npages;
 }
 
+static inline int is_span_boundary(unsigned long entry,
+                                   unsigned long shift,
+                                   unsigned long boundary_size,
+                                   struct scatterlist *outs,
+                                   struct scatterlist *sg)
+{
+        unsigned long paddr = SG_ENT_PHYS_ADDRESS(outs);
+        int nr = iommu_num_pages(paddr, outs->dma_length + sg->length);
+
+        return iommu_is_span_boundary(entry, nr, shift, boundary_size);
+}
+
 extern unsigned long iommu_range_alloc(struct device *dev,
                                        struct iommu *iommu,
                                        unsigned long npages,
diff --git a/arch/sparc64/kernel/pci_sun4v.c b/arch/sparc64/kernel/pci_sun4v.c
index ddca6c6c0b49..01839706bd52 100644
--- a/arch/sparc64/kernel/pci_sun4v.c
+++ b/arch/sparc64/kernel/pci_sun4v.c
@@ -335,8 +335,10 @@ static int dma_4v_map_sg(struct device *dev, struct scatterlist *sglist,
         unsigned long flags, handle, prot;
         dma_addr_t dma_next = 0, dma_addr;
         unsigned int max_seg_size;
+        unsigned long seg_boundary_size;
         int outcount, incount, i;
         struct iommu *iommu;
+        unsigned long base_shift;
         long err;
 
         BUG_ON(direction == DMA_NONE);
@@ -362,8 +364,11 @@ static int dma_4v_map_sg(struct device *dev, struct scatterlist *sglist,
         iommu_batch_start(dev, prot, ~0UL);
 
         max_seg_size = dma_get_max_seg_size(dev);
+        seg_boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1,
+                                  IO_PAGE_SIZE) >> IO_PAGE_SHIFT;
+        base_shift = iommu->page_table_map_base >> IO_PAGE_SHIFT;
         for_each_sg(sglist, s, nelems, i) {
-                unsigned long paddr, npages, entry, slen;
+                unsigned long paddr, npages, entry, out_entry = 0, slen;
 
                 slen = s->length;
                 /* Sanity check */
@@ -406,7 +411,9 @@ static int dma_4v_map_sg(struct device *dev, struct scatterlist *sglist,
                          * - allocated dma_addr isn't contiguous to previous allocation
                          */
                         if ((dma_addr != dma_next) ||
-                            (outs->dma_length + s->length > max_seg_size)) {
+                            (outs->dma_length + s->length > max_seg_size) ||
+                            (is_span_boundary(out_entry, base_shift,
+                                              seg_boundary_size, outs, s))) {
                                 /* Can't merge: create a new segment */
                                 segstart = s;
                                 outcount++;
@@ -420,6 +427,7 @@ static int dma_4v_map_sg(struct device *dev, struct scatterlist *sglist,
                         /* This is a new segment, fill entries */
                         outs->dma_address = dma_addr;
                         outs->dma_length = slen;
+                        out_entry = entry;
                 }
 
                 /* Calculate next page pointer for contiguous check */