SPARC64: sg chaining support
This updates the sparc64 iommu/pci dma mappers to sg chaining.
Acked-by: David S. Miller <davem@davemloft.net>
Later updated to newer kernel with unified sparc64 iommu sg handling.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/arch/sparc64/kernel/iommu.c b/arch/sparc64/kernel/iommu.c
index b35a621..db3ffcf 100644
--- a/arch/sparc64/kernel/iommu.c
+++ b/arch/sparc64/kernel/iommu.c
@@ -10,6 +10,7 @@
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/errno.h>
+#include <linux/scatterlist.h>
#ifdef CONFIG_PCI
#include <linux/pci.h>
@@ -480,7 +481,7 @@
unsigned long iopte_protection)
{
struct scatterlist *dma_sg = sg;
- struct scatterlist *sg_end = sg + nelems;
+ struct scatterlist *sg_end = sg_last(sg, nelems);
int i;
for (i = 0; i < nused; i++) {
@@ -515,7 +516,7 @@
len -= (IO_PAGE_SIZE - (tmp & (IO_PAGE_SIZE - 1UL)));
break;
}
- sg++;
+ sg = sg_next(sg);
}
pteval = iopte_protection | (pteval & IOPTE_PAGE);
@@ -528,24 +529,24 @@
}
pteval = (pteval & IOPTE_PAGE) + len;
- sg++;
+ sg = sg_next(sg);
/* Skip over any tail mappings we've fully mapped,
* adjusting pteval along the way. Stop when we
* detect a page crossing event.
*/
- while (sg < sg_end &&
+ while (sg != sg_end &&
(pteval << (64 - IO_PAGE_SHIFT)) != 0UL &&
(pteval == SG_ENT_PHYS_ADDRESS(sg)) &&
((pteval ^
(SG_ENT_PHYS_ADDRESS(sg) + sg->length - 1UL)) >> IO_PAGE_SHIFT) == 0UL) {
pteval += sg->length;
- sg++;
+ sg = sg_next(sg);
}
if ((pteval << (64 - IO_PAGE_SHIFT)) == 0UL)
pteval = ~0UL;
} while (dma_npages != 0);
- dma_sg++;
+ dma_sg = sg_next(dma_sg);
}
}
@@ -606,7 +607,7 @@
sgtmp = sglist;
while (used && sgtmp->dma_length) {
sgtmp->dma_address += dma_base;
- sgtmp++;
+ sgtmp = sg_next(sgtmp);
used--;
}
used = nelems - used;
@@ -642,6 +643,7 @@
struct strbuf *strbuf;
iopte_t *base;
unsigned long flags, ctx, i, npages;
+ struct scatterlist *sg, *sgprv;
u32 bus_addr;
if (unlikely(direction == DMA_NONE)) {
@@ -654,11 +656,14 @@
bus_addr = sglist->dma_address & IO_PAGE_MASK;
- for (i = 1; i < nelems; i++)
- if (sglist[i].dma_length == 0)
+ sgprv = NULL;
+ for_each_sg(sglist, sg, nelems, i) {
+ if (sg->dma_length == 0)
break;
- i--;
- npages = (IO_PAGE_ALIGN(sglist[i].dma_address + sglist[i].dma_length) -
+ sgprv = sg;
+ }
+
+ npages = (IO_PAGE_ALIGN(sgprv->dma_address + sgprv->dma_length) -
bus_addr) >> IO_PAGE_SHIFT;
base = iommu->page_table +
@@ -730,6 +735,7 @@
struct iommu *iommu;
struct strbuf *strbuf;
unsigned long flags, ctx, npages, i;
+ struct scatterlist *sg, *sgprv;
u32 bus_addr;
iommu = dev->archdata.iommu;
@@ -753,11 +759,14 @@
/* Step 2: Kick data out of streaming buffers. */
bus_addr = sglist[0].dma_address & IO_PAGE_MASK;
- for(i = 1; i < nelems; i++)
- if (!sglist[i].dma_length)
+ sgprv = NULL;
+ for_each_sg(sglist, sg, nelems, i) {
+ if (sg->dma_length == 0)
break;
- i--;
- npages = (IO_PAGE_ALIGN(sglist[i].dma_address + sglist[i].dma_length)
+ sgprv = sg;
+ }
+
+ npages = (IO_PAGE_ALIGN(sgprv->dma_address + sgprv->dma_length)
- bus_addr) >> IO_PAGE_SHIFT;
strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction);
diff --git a/arch/sparc64/kernel/pci_sun4v.c b/arch/sparc64/kernel/pci_sun4v.c
index 95de144..cacacfa 100644
--- a/arch/sparc64/kernel/pci_sun4v.c
+++ b/arch/sparc64/kernel/pci_sun4v.c
@@ -13,6 +13,7 @@
#include <linux/irq.h>
#include <linux/msi.h>
#include <linux/log2.h>
+#include <linux/scatterlist.h>
#include <asm/iommu.h>
#include <asm/irq.h>
@@ -373,7 +374,7 @@
int nused, int nelems, unsigned long prot)
{
struct scatterlist *dma_sg = sg;
- struct scatterlist *sg_end = sg + nelems;
+ struct scatterlist *sg_end = sg_last(sg, nelems);
unsigned long flags;
int i;
@@ -413,7 +414,7 @@
len -= (IO_PAGE_SIZE - (tmp & (IO_PAGE_SIZE - 1UL)));
break;
}
- sg++;
+ sg = sg_next(sg);
}
pteval = (pteval & IOPTE_PAGE);
@@ -431,24 +432,25 @@
}
pteval = (pteval & IOPTE_PAGE) + len;
- sg++;
+ sg = sg_next(sg);
/* Skip over any tail mappings we've fully mapped,
* adjusting pteval along the way. Stop when we
* detect a page crossing event.
*/
- while (sg < sg_end &&
- (pteval << (64 - IO_PAGE_SHIFT)) != 0UL &&
+ while ((pteval << (64 - IO_PAGE_SHIFT)) != 0UL &&
(pteval == SG_ENT_PHYS_ADDRESS(sg)) &&
((pteval ^
(SG_ENT_PHYS_ADDRESS(sg) + sg->length - 1UL)) >> IO_PAGE_SHIFT) == 0UL) {
pteval += sg->length;
- sg++;
+ if (sg == sg_end)
+ break;
+ sg = sg_next(sg);
}
if ((pteval << (64 - IO_PAGE_SHIFT)) == 0UL)
pteval = ~0UL;
} while (dma_npages != 0);
- dma_sg++;
+ dma_sg = sg_next(dma_sg);
}
if (unlikely(iommu_batch_end() < 0L))
@@ -510,7 +512,7 @@
sgtmp = sglist;
while (used && sgtmp->dma_length) {
sgtmp->dma_address += dma_base;
- sgtmp++;
+ sgtmp = sg_next(sgtmp);
used--;
}
used = nelems - used;
@@ -545,6 +547,7 @@
struct pci_pbm_info *pbm;
struct iommu *iommu;
unsigned long flags, i, npages;
+ struct scatterlist *sg, *sgprv;
long entry;
u32 devhandle, bus_addr;
@@ -558,12 +561,15 @@
devhandle = pbm->devhandle;
bus_addr = sglist->dma_address & IO_PAGE_MASK;
-
- for (i = 1; i < nelems; i++)
- if (sglist[i].dma_length == 0)
+ sgprv = NULL;
+ for_each_sg(sglist, sg, nelems, i) {
+ if (sg->dma_length == 0)
break;
- i--;
- npages = (IO_PAGE_ALIGN(sglist[i].dma_address + sglist[i].dma_length) -
+
+ sgprv = sg;
+ }
+
+ npages = (IO_PAGE_ALIGN(sgprv->dma_address + sgprv->dma_length) -
bus_addr) >> IO_PAGE_SHIFT;
entry = ((bus_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT);
diff --git a/include/asm-sparc64/scatterlist.h b/include/asm-sparc64/scatterlist.h
index 048fdb4..703c5bb 100644
--- a/include/asm-sparc64/scatterlist.h
+++ b/include/asm-sparc64/scatterlist.h
@@ -20,4 +20,6 @@
#define ISA_DMA_THRESHOLD (~0UL)
+#define ARCH_HAS_SG_CHAIN
+
#endif /* !(_SPARC64_SCATTERLIST_H) */