x86-64: update pci-gart iommu to sg helpers

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/arch/x86/kernel/pci-gart_64.c b/arch/x86/kernel/pci-gart_64.c
index 4918c575d582cfd901ca23f47e8327a16045998f..cfcc84e6c350886f8fe19db070511ce950afa3cb 100644 (file)
--- a/arch/x86/kernel/pci-gart_64.c
+++ b/arch/x86/kernel/pci-gart_64.c
@@ -23,6 +23,7 @@
 #include <linux/interrupt.h>
 #include <linux/bitops.h>
 #include <linux/kdebug.h>
+#include <linux/scatterlist.h>
 #include <asm/atomic.h>
 #include <asm/io.h>
 #include <asm/mtrr.h>
@@ -278,10 +279,10 @@ static void gart_unmap_single(struct device *dev, dma_addr_t dma_addr,
  */
 static void gart_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
 {
+       struct scatterlist *s;
        int i;
 
-       for (i = 0; i < nents; i++) {
-               struct scatterlist *s = &sg[i];
+       for_each_sg(sg, s, nents, i) {
                if (!s->dma_length || !s->length)
                        break;
                gart_unmap_single(dev, s->dma_address, s->dma_length, dir);
@@ -292,14 +293,14 @@ static void gart_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
 static int dma_map_sg_nonforce(struct device *dev, struct scatterlist *sg,
                               int nents, int dir)
 {
+       struct scatterlist *s;
        int i;
 
 #ifdef CONFIG_IOMMU_DEBUG
        printk(KERN_DEBUG "dma_map_sg overflow\n");
 #endif
 
-       for (i = 0; i < nents; i++ ) {
-               struct scatterlist *s = &sg[i];
+       for_each_sg(sg, s, nents, i) {
                unsigned long addr = page_to_phys(s->page) + s->offset; 
                if (nonforced_iommu(dev, addr, s->length)) { 
                        addr = dma_map_area(dev, addr, s->length, dir);
@@ -319,23 +320,23 @@ static int dma_map_sg_nonforce(struct device *dev, struct scatterlist *sg,
 }
 
 /* Map multiple scatterlist entries continuous into the first. */
-static int __dma_map_cont(struct scatterlist *sg, int start, int stopat,
+static int __dma_map_cont(struct scatterlist *start, int nelems,
                      struct scatterlist *sout, unsigned long pages)
 {
        unsigned long iommu_start = alloc_iommu(pages);
        unsigned long iommu_page = iommu_start; 
+       struct scatterlist *s;
        int i;
 
        if (iommu_start == -1)
                return -1;
-       
-       for (i = start; i < stopat; i++) {
-               struct scatterlist *s = &sg[i];
+
+       for_each_sg(start, s, nelems, i) {
                unsigned long pages, addr;
                unsigned long phys_addr = s->dma_address;
                
-               BUG_ON(i > start && s->offset);
-               if (i == start) {
+               BUG_ON(s != start && s->offset);
+               if (s == start) {
                        *sout = *s; 
                        sout->dma_address = iommu_bus_base;
                        sout->dma_address += iommu_page*PAGE_SIZE + s->offset;
@@ -357,17 +358,17 @@ static int __dma_map_cont(struct scatterlist *sg, int start, int stopat,
        return 0;
 }
 
-static inline int dma_map_cont(struct scatterlist *sg, int start, int stopat,
+static inline int dma_map_cont(struct scatterlist *start, int nelems,
                      struct scatterlist *sout,
                      unsigned long pages, int need)
 {
-       if (!need) { 
-               BUG_ON(stopat - start != 1);
-               *sout = sg[start]; 
-               sout->dma_length = sg[start].length; 
+       if (!need) {
+               BUG_ON(nelems != 1);
+               *sout = *start;
+               sout->dma_length = start->length;
                return 0;
-       } 
-       return __dma_map_cont(sg, start, stopat, sout, pages);
+       }
+       return __dma_map_cont(start, nelems, sout, pages);
 }
                
 /*
@@ -381,6 +382,7 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
        int start;
        unsigned long pages = 0;
        int need = 0, nextneed;
+       struct scatterlist *s, *ps, *start_sg, *sgmap;
 
        if (nents == 0) 
                return 0;
@@ -390,8 +392,9 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
 
        out = 0;
        start = 0;
-       for (i = 0; i < nents; i++) {
-               struct scatterlist *s = &sg[i];
+       start_sg = sgmap = sg;
+       ps = NULL; /* shut up gcc */
+       for_each_sg(sg, s, nents, i) {
                dma_addr_t addr = page_to_phys(s->page) + s->offset;
                s->dma_address = addr;
                BUG_ON(s->length == 0); 
@@ -400,29 +403,33 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
 
                /* Handle the previous not yet processed entries */
                if (i > start) {
-                       struct scatterlist *ps = &sg[i-1];
                        /* Can only merge when the last chunk ends on a page 
                           boundary and the new one doesn't have an offset. */
                        if (!iommu_merge || !nextneed || !need || s->offset ||
-                           (ps->offset + ps->length) % PAGE_SIZE) { 
-                               if (dma_map_cont(sg, start, i, sg+out, pages,
-                                                need) < 0)
+                           (ps->offset + ps->length) % PAGE_SIZE) {
+                               if (dma_map_cont(start_sg, i - start, sgmap,
+                                                 pages, need) < 0)
                                        goto error;
                                out++;
+                               sgmap = sg_next(sgmap);
                                pages = 0;
-                               start = i;      
+                               start = i;
+                               start_sg = s;
                        }
                }
 
                need = nextneed;
                pages += to_pages(s->offset, s->length);
+               ps = s;
        }
-       if (dma_map_cont(sg, start, i, sg+out, pages, need) < 0)
+       if (dma_map_cont(start_sg, i - start, sgmap, pages, need) < 0)
                goto error;
        out++;
        flush_gart();
-       if (out < nents) 
-               sg[out].dma_length = 0; 
+       if (out < nents) {
+               sgmap = sg_next(sgmap);
+               sgmap->dma_length = 0;
+       }
        return out;
 
 error:
@@ -437,8 +444,8 @@ error:
        if (panic_on_overflow)
                panic("dma_map_sg: overflow on %lu pages\n", pages);
        iommu_full(dev, pages << PAGE_SHIFT, dir);
-       for (i = 0; i < nents; i++)
-               sg[i].dma_address = bad_dma_address;
+       for_each_sg(sg, s, nents, i)
+               s->dma_address = bad_dma_address;
        return 0;
 }