SPARC64: fix iommu sg chaining

Commit 2c941a204070ab32d92d40318a3196a7fb994c00 looks incomplete. The
helper functions like prepare_sg() need to support sg chaining too.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

4 files changed, 31 insertions, 23 deletions

diff --git a/arch/sparc64/kernel/iommu.c b/arch/sparc64/kernel/iommu.c
index db3ffcf7a120..5d4e96dba412 100644
--- a/arch/sparc64/kernel/iommu.c
+++ b/arch/sparc64/kernel/iommu.c
@@ -10,7 +10,6 @@
 #include <linux/device.h>
 #include <linux/dma-mapping.h>
 #include <linux/errno.h>
-#include <linux/scatterlist.h>
 
 #ifdef CONFIG_PCI
 #include <linux/pci.h>
diff --git a/arch/sparc64/kernel/iommu_common.c b/arch/sparc64/kernel/iommu_common.c
index 12c93a3eee26..d7ca900ec51d 100644
--- a/arch/sparc64/kernel/iommu_common.c
+++ b/arch/sparc64/kernel/iommu_common.c
@@ -12,18 +12,22 @@
  */
 
 #ifdef VERIFY_SG
-static int verify_lengths(struct scatterlist *sg, int nents, int npages)
+static int verify_lengths(struct scatterlist *sglist, int nents, int npages)
 {
         int sg_len, dma_len;
         int i, pgcount;
+        struct scatterlist *sg;
 
         sg_len = 0;
-        for (i = 0; i < nents; i++)
-                sg_len += sg[i].length;
+        for_each_sg(sglist, sg, nents, i)
+                sg_len += sg->length;
 
         dma_len = 0;
-        for (i = 0; i < nents && sg[i].dma_length; i++)
-                dma_len += sg[i].dma_length;
+        for_each_sg(sglist, sg, nents, i) {
+                if (!sg->dma_length)
+                        break;
+                dma_len += sg->dma_length;
+        }
 
         if (sg_len != dma_len) {
                 printk("verify_lengths: Error, different, sg[%d] dma[%d]\n",
@@ -32,13 +36,16 @@ static int verify_lengths(struct scatterlist *sg, int nents, int npages)
         }
 
         pgcount = 0;
-        for (i = 0; i < nents && sg[i].dma_length; i++) {
+        for_each_sg(sglist, sg, nents, i) {
                 unsigned long start, end;
 
-                start = sg[i].dma_address;
+                if (!sg->dma_length)
+                        break;
+
+                start = sg->dma_address;
                 start = start & IO_PAGE_MASK;
 
-                end = sg[i].dma_address + sg[i].dma_length;
+                end = sg->dma_address + sg->dma_length;
                 end = (end + (IO_PAGE_SIZE - 1)) & IO_PAGE_MASK;
 
                 pgcount += ((end - start) >> IO_PAGE_SHIFT);
@@ -113,7 +120,7 @@ static int verify_one_map(struct scatterlist *dma_sg, struct scatterlist **__sg,
                 if (dlen > 0 && ((daddr & ~IO_PAGE_MASK) == 0))
                         iopte++;
 
-                sg++;
+                sg = sg_next(sg);
                 if (--nents <= 0)
                         break;
                 sgaddr = (unsigned long) (page_address(sg->page) + sg->offset);
@@ -147,7 +154,7 @@ static int verify_maps(struct scatterlist *sg, int nents, iopte_t *iopte)
                 nents = verify_one_map(dma_sg, &sg, nents, &iopte);
                 if (nents <= 0)
                         break;
-                dma_sg++;
+                dma_sg = sg_next(dma_sg);
                 if (dma_sg->dma_length == 0)
                         break;
         }
@@ -169,22 +176,24 @@ static int verify_maps(struct scatterlist *sg, int nents, iopte_t *iopte)
         return 0;
 }
 
-void verify_sglist(struct scatterlist *sg, int nents, iopte_t *iopte, int npages)
+void verify_sglist(struct scatterlist *sglist, int nents, iopte_t *iopte, int npages)
 {
-        if (verify_lengths(sg, nents, npages) < 0 ||
-            verify_maps(sg, nents, iopte) < 0) {
+        struct scatterlist *sg;
+
+        if (verify_lengths(sglist, nents, npages) < 0 ||
+            verify_maps(sglist, nents, iopte) < 0) {
                 int i;
 
                 printk("verify_sglist: Crap, messed up mappings, dumping, iodma at ");
-                printk("%016lx.\n", sg->dma_address & IO_PAGE_MASK);
+                printk("%016lx.\n", sglist->dma_address & IO_PAGE_MASK);
 
-                for (i = 0; i < nents; i++) {
+                for_each_sg(sglist, sg, nents, i) {
                         printk("sg(%d): page_addr(%p) off(%x) length(%x) "
-                               "dma_address[%016lx] dma_length[%016lx]\n",
+                               "dma_address[%016x] dma_length[%016x]\n",
                                i,
-                               page_address(sg[i].page), sg[i].offset,
-                               sg[i].length,
-                               sg[i].dma_address, sg[i].dma_length);
+                               page_address(sg->page), sg->offset,
+                               sg->length,
+                               sg->dma_address, sg->dma_length);
                 }
         }
 
@@ -205,12 +214,12 @@ unsigned long prepare_sg(struct scatterlist *sg, int nents)
         while (--nents) {
                 unsigned long addr;
 
-                sg++;
+                sg = sg_next(sg);
                 addr = (unsigned long) (page_address(sg->page) + sg->offset);
                 if (! VCONTIG(prev, addr)) {
                         dma_sg->dma_address = dent_addr;
                         dma_sg->dma_length = dent_len;
-                        dma_sg++;
+                        dma_sg = sg_next(dma_sg);
 
                         dent_addr = ((dent_addr +
                                       dent_len +
diff --git a/arch/sparc64/kernel/iommu_common.h b/arch/sparc64/kernel/iommu_common.h
index ad791014419c..75b5a5814522 100644
--- a/arch/sparc64/kernel/iommu_common.h
+++ b/arch/sparc64/kernel/iommu_common.h
@@ -8,6 +8,7 @@
 #include <linux/types.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
+#include <linux/scatterlist.h>
 
 #include <asm/iommu.h>
 #include <asm/scatterlist.h>
diff --git a/arch/sparc64/kernel/pci_sun4v.c b/arch/sparc64/kernel/pci_sun4v.c
index cacacfae5451..119f8efa03d2 100644
--- a/arch/sparc64/kernel/pci_sun4v.c
+++ b/arch/sparc64/kernel/pci_sun4v.c
@@ -13,7 +13,6 @@
 #include <linux/irq.h>
 #include <linux/msi.h>
 #include <linux/log2.h>
-#include <linux/scatterlist.h>
 
 #include <asm/iommu.h>
 #include <asm/irq.h>