diff mbox series

[3/6] sparc: remove the sparc32_dma_ops indirection

Message ID 20181208174115.16237-4-hch@lst.de (mailing list archive)
State Not Applicable
Headers show
Series [1/6] sparc: remove no needed sbus_dma_ops methods | expand

Commit Message

hch@lst.de Dec. 8, 2018, 5:41 p.m. UTC
There is no good reason to have a double indirection for the sparc32
dma ops, so remove the sparc32_dma_ops and define separate dma_map_ops
instance for the different IOMMU types.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/sparc/include/asm/dma.h |  48 +-----------
 arch/sparc/kernel/ioport.c   | 124 +------------------------------
 arch/sparc/mm/io-unit.c      |  65 ++++++++++++-----
 arch/sparc/mm/iommu.c        | 137 ++++++++++++++++++++++-------------
 4 files changed, 138 insertions(+), 236 deletions(-)

Comments

David Miller Dec. 9, 2018, 4:57 a.m. UTC | #1
From: Christoph Hellwig <hch@lst.de>
Date: Sat,  8 Dec 2018 09:41:12 -0800

> There is no good reason to have a double indirection for the sparc32
> dma ops, so remove the sparc32_dma_ops and define separate dma_map_ops
> instance for the different IOMMU types.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Acked-by: David S. Miller <davem@davemloft.net>
Guenter Roeck Dec. 15, 2018, 6:30 a.m. UTC | #2
On Sat, Dec 08, 2018 at 09:41:12AM -0800, Christoph Hellwig wrote:
> There is no good reason to have a double indirection for the sparc32
> dma ops, so remove the sparc32_dma_ops and define separate dma_map_ops
> instance for the different IOMMU types.
> 

Except maybe this:

scsi host0: esp
scsi host0: Data transfer overflow.
scsi host0: cur_residue[0] tot_residue[-36] len[36]
scsi 0:0:0:0: Direct-Access     QEMU     QEMU HARDDISK    2.5+ PQ: 0 ANSI: 5
scsi target0:0:0: Beginning Domain Validation
scsi host0: Data transfer overflow.
scsi host0: cur_residue[0] tot_residue[-36] len[36]
scsi host0: Data transfer overflow.
scsi host0: cur_residue[0] tot_residue[-36] len[36]
scsi host0: Data transfer overflow.
scsi host0: cur_residue[0] tot_residue[-36] len[36]
scsi host0: Data transfer overflow.
scsi host0: cur_residue[0] tot_residue[-36] len[36]

and so on, until qemu is terminated. This is seen with all sparc32
qemu emulations. Reverting the patch fixes the problem.

Guenter
hch@lst.de Dec. 15, 2018, 10:47 a.m. UTC | #3
On Fri, Dec 14, 2018 at 10:30:18PM -0800, Guenter Roeck wrote:
> and so on, until qemu is terminated. This is seen with all sparc32
> qemu emulations. Reverting the patch fixes the problem.

Hi Guenter,

can you check which of the three new ops is used in this case?  Or
provide the qemu config and rootfs?
Guenter Roeck Dec. 15, 2018, 2:57 p.m. UTC | #4
On 12/15/18 2:47 AM, Christoph Hellwig wrote:
> On Fri, Dec 14, 2018 at 10:30:18PM -0800, Guenter Roeck wrote:
>> and so on, until qemu is terminated. This is seen with all sparc32
>> qemu emulations. Reverting the patch fixes the problem.
> 
> Hi Guenter,
> 
> can you check which of the three new ops is used in this case?  Or
> provide the qemu config and rootfs?
> 

sparc32 defconfig+CONFIG_SQUASHFS=y+CONFIG_DEVTMPFS=y, and:

qemu-system-sparc -M SPARCClassic -kernel arch/sparc/boot/image \
	-no-reboot -snapshot -drive file=/var/cache/buildbot/sparc/hda.sqf,if=scsi,format=raw \
	-append 'root=/dev/sda rw init=/sbin/init.sh panic=1 console=ttyS0' \
	-nographic

qemu version doesn't seem to matter. I used gcc-7.3.0 using the toolchain from kernel.org
to build the image.

Root file system is at https://github.com/groeck/linux-build-test/tree/master/rootfs/sparc/.

Guenter
diff mbox series

Patch

diff --git a/arch/sparc/include/asm/dma.h b/arch/sparc/include/asm/dma.h
index a1d7c86917c6..462e7c794a09 100644
--- a/arch/sparc/include/asm/dma.h
+++ b/arch/sparc/include/asm/dma.h
@@ -91,54 +91,10 @@  extern int isa_dma_bridge_buggy;
 #endif
 
 #ifdef CONFIG_SPARC32
-
-/* Routines for data transfer buffers. */
 struct device;
-struct scatterlist;
-
-struct sparc32_dma_ops {
-	__u32 (*get_scsi_one)(struct device *, char *, unsigned long);
-	void (*get_scsi_sgl)(struct device *, struct scatterlist *, int);
-	void (*release_scsi_one)(struct device *, __u32, unsigned long);
-	void (*release_scsi_sgl)(struct device *, struct scatterlist *,int);
-#ifdef CONFIG_SBUS
-	int (*map_dma_area)(struct device *, dma_addr_t *, unsigned long, unsigned long, int);
-	void (*unmap_dma_area)(struct device *, unsigned long, int);
-#endif
-};
-extern const struct sparc32_dma_ops *sparc32_dma_ops;
-
-#define mmu_get_scsi_one(dev,vaddr,len) \
-	sparc32_dma_ops->get_scsi_one(dev, vaddr, len)
-#define mmu_get_scsi_sgl(dev,sg,sz) \
-	sparc32_dma_ops->get_scsi_sgl(dev, sg, sz)
-#define mmu_release_scsi_one(dev,vaddr,len) \
-	sparc32_dma_ops->release_scsi_one(dev, vaddr,len)
-#define mmu_release_scsi_sgl(dev,sg,sz) \
-	sparc32_dma_ops->release_scsi_sgl(dev, sg, sz)
-
-#ifdef CONFIG_SBUS
-/*
- * mmu_map/unmap are provided by iommu/iounit; Invalid to call on IIep.
- *
- * The mmu_map_dma_area establishes two mappings in one go.
- * These mappings point to pages normally mapped at 'va' (linear address).
- * First mapping is for CPU visible address at 'a', uncached.
- * This is an alias, but it works because it is an uncached mapping.
- * Second mapping is for device visible address, or "bus" address.
- * The bus address is returned at '*pba'.
- *
- * These functions seem distinct, but are hard to split.
- * On sun4m, page attributes depend on the CPU type, so we have to
- * know if we are mapping RAM or I/O, so it has to be an additional argument
- * to a separate mapping function for CPU visible mappings.
- */
-#define sbus_map_dma_area(dev,pba,va,a,len) \
-	sparc32_dma_ops->map_dma_area(dev, pba, va, a, len)
-#define sbus_unmap_dma_area(dev,ba,len) \
-	sparc32_dma_ops->unmap_dma_area(dev, ba, len)
-#endif /* CONFIG_SBUS */
 
+unsigned long sparc_dma_alloc_resource(struct device *dev, size_t len);
+bool sparc_dma_free_resource(void *cpu_addr, size_t size);
 #endif
 
 #endif /* !(_ASM_SPARC_DMA_H) */
diff --git a/arch/sparc/kernel/ioport.c b/arch/sparc/kernel/ioport.c
index fd7a41c6d688..f46213035637 100644
--- a/arch/sparc/kernel/ioport.c
+++ b/arch/sparc/kernel/ioport.c
@@ -52,8 +52,6 @@ 
 #include <asm/io-unit.h>
 #include <asm/leon.h>
 
-const struct sparc32_dma_ops *sparc32_dma_ops;
-
 /* This function must make sure that caches and memory are coherent after DMA
  * On LEON systems without cache snooping it flushes the entire D-CACHE.
  */
@@ -247,7 +245,7 @@  static void _sparc_free_io(struct resource *res)
 	release_resource(res);
 }
 
-static unsigned long sparc_dma_alloc_resource(struct device *dev, size_t len)
+unsigned long sparc_dma_alloc_resource(struct device *dev, size_t len)
 {
 	struct resource *res;
 
@@ -266,7 +264,7 @@  static unsigned long sparc_dma_alloc_resource(struct device *dev, size_t len)
 	return res->start;
 }
 
-static bool sparc_dma_free_resource(void *cpu_addr, size_t size)
+bool sparc_dma_free_resource(void *cpu_addr, size_t size)
 {
 	unsigned long addr = (unsigned long)cpu_addr;
 	struct resource *res;
@@ -302,122 +300,6 @@  void sbus_set_sbus64(struct device *dev, int x)
 }
 EXPORT_SYMBOL(sbus_set_sbus64);
 
-/*
- * Allocate a chunk of memory suitable for DMA.
- * Typically devices use them for control blocks.
- * CPU may access them without any explicit flushing.
- */
-static void *sbus_alloc_coherent(struct device *dev, size_t len,
-				 dma_addr_t *dma_addrp, gfp_t gfp,
-				 unsigned long attrs)
-{
-	unsigned long len_total = PAGE_ALIGN(len);
-	unsigned long va, addr;
-	int order;
-
-	/* XXX why are some lengths signed, others unsigned? */
-	if (len <= 0) {
-		return NULL;
-	}
-	/* XXX So what is maxphys for us and how do drivers know it? */
-	if (len > 256*1024) {			/* __get_free_pages() limit */
-		return NULL;
-	}
-
-	order = get_order(len_total);
-	va = __get_free_pages(gfp, order);
-	if (va == 0)
-		goto err_nopages;
-
-	addr = sparc_dma_alloc_resource(dev, len_total);
-	if (!addr)
-		goto err_nomem;
-
-	// XXX The sbus_map_dma_area does this for us below, see comments.
-	// srmmu_mapiorange(0, virt_to_phys(va), res->start, len_total);
-	/*
-	 * XXX That's where sdev would be used. Currently we load
-	 * all iommu tables with the same translations.
-	 */
-	if (sbus_map_dma_area(dev, dma_addrp, va, addr, len_total) != 0)
-		goto err_noiommu;
-
-	return (void *)addr;
-
-err_noiommu:
-	sparc_dma_free_resource((void *)addr, len_total);
-err_nomem:
-	free_pages(va, order);
-err_nopages:
-	return NULL;
-}
-
-static void sbus_free_coherent(struct device *dev, size_t n, void *p,
-			       dma_addr_t ba, unsigned long attrs)
-{
-	struct page *pgv;
-
-	n = PAGE_ALIGN(n);
-	if (!sparc_dma_free_resource(p, n))
-		return;
-
-	pgv = virt_to_page(p);
-	sbus_unmap_dma_area(dev, ba, n);
-
-	__free_pages(pgv, get_order(n));
-}
-
-/*
- * Map a chunk of memory so that devices can see it.
- * CPU view of this memory may be inconsistent with
- * a device view and explicit flushing is necessary.
- */
-static dma_addr_t sbus_map_page(struct device *dev, struct page *page,
-				unsigned long offset, size_t len,
-				enum dma_data_direction dir,
-				unsigned long attrs)
-{
-	void *va = page_address(page) + offset;
-
-	/* XXX why are some lengths signed, others unsigned? */
-	if (len <= 0) {
-		return 0;
-	}
-	/* XXX So what is maxphys for us and how do drivers know it? */
-	if (len > 256*1024) {			/* __get_free_pages() limit */
-		return 0;
-	}
-	return mmu_get_scsi_one(dev, va, len);
-}
-
-static void sbus_unmap_page(struct device *dev, dma_addr_t ba, size_t n,
-			    enum dma_data_direction dir, unsigned long attrs)
-{
-	mmu_release_scsi_one(dev, ba, n);
-}
-
-static int sbus_map_sg(struct device *dev, struct scatterlist *sg, int n,
-		       enum dma_data_direction dir, unsigned long attrs)
-{
-	mmu_get_scsi_sgl(dev, sg, n);
-	return n;
-}
-
-static void sbus_unmap_sg(struct device *dev, struct scatterlist *sg, int n,
-			  enum dma_data_direction dir, unsigned long attrs)
-{
-	mmu_release_scsi_sgl(dev, sg, n);
-}
-
-static const struct dma_map_ops sbus_dma_ops = {
-	.alloc			= sbus_alloc_coherent,
-	.free			= sbus_free_coherent,
-	.map_page		= sbus_map_page,
-	.unmap_page		= sbus_unmap_page,
-	.map_sg			= sbus_map_sg,
-	.unmap_sg		= sbus_unmap_sg,
-};
-
 static int __init sparc_register_ioport(void)
 {
 	register_proc_sparc_ioport();
@@ -491,7 +373,7 @@  void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
 		dma_make_coherent(paddr, PAGE_ALIGN(size));
 }
 
-const struct dma_map_ops *dma_ops = &sbus_dma_ops;
+const struct dma_map_ops *dma_ops;
 EXPORT_SYMBOL(dma_ops);
 
 #ifdef CONFIG_PROC_FS
diff --git a/arch/sparc/mm/io-unit.c b/arch/sparc/mm/io-unit.c
index c8cb27d3ea75..2088d292c6e5 100644
--- a/arch/sparc/mm/io-unit.c
+++ b/arch/sparc/mm/io-unit.c
@@ -12,7 +12,7 @@ 
 #include <linux/mm.h>
 #include <linux/highmem.h>	/* pte_offset_map => kmap_atomic */
 #include <linux/bitops.h>
-#include <linux/scatterlist.h>
+#include <linux/dma-mapping.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 
@@ -140,18 +140,26 @@  nexti:	scan = find_next_zero_bit(iounit->bmap, limit, scan);
 	return vaddr;
 }
 
-static __u32 iounit_get_scsi_one(struct device *dev, char *vaddr, unsigned long len)
+static dma_addr_t iounit_map_page(struct device *dev, struct page *page,
+		unsigned long offset, size_t len, enum dma_data_direction dir,
+		unsigned long attrs)
 {
+	void *vaddr = page_address(page) + offset;
 	struct iounit_struct *iounit = dev->archdata.iommu;
 	unsigned long ret, flags;
 	
+	/* XXX So what is maxphys for us and how do drivers know it? */
+	if (!len || len > 256 * 1024)
+		return DMA_MAPPING_ERROR;
+
 	spin_lock_irqsave(&iounit->lock, flags);
 	ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
 	spin_unlock_irqrestore(&iounit->lock, flags);
 	return ret;
 }
 
-static void iounit_get_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz)
+static int iounit_map_sg(struct device *dev, struct scatterlist *sg, int sz,
+		enum dma_data_direction dir, unsigned long attrs)
 {
 	struct iounit_struct *iounit = dev->archdata.iommu;
 	unsigned long flags;
@@ -165,9 +173,11 @@  static void iounit_get_scsi_sgl(struct device *dev, struct scatterlist *sg, int
 		sg = sg_next(sg);
 	}
 	spin_unlock_irqrestore(&iounit->lock, flags);
+	return sz;
 }
 
-static void iounit_release_scsi_one(struct device *dev, __u32 vaddr, unsigned long len)
+static void iounit_unmap_page(struct device *dev, dma_addr_t vaddr, size_t len,
+		enum dma_data_direction dir, unsigned long attrs)
 {
 	struct iounit_struct *iounit = dev->archdata.iommu;
 	unsigned long flags;
@@ -181,7 +191,8 @@  static void iounit_release_scsi_one(struct device *dev, __u32 vaddr, unsigned lo
 	spin_unlock_irqrestore(&iounit->lock, flags);
 }
 
-static void iounit_release_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz)
+static void iounit_unmap_sg(struct device *dev, struct scatterlist *sg, int sz,
+		enum dma_data_direction dir, unsigned long attrs)
 {
 	struct iounit_struct *iounit = dev->archdata.iommu;
 	unsigned long flags;
@@ -201,14 +212,27 @@  static void iounit_release_scsi_sgl(struct device *dev, struct scatterlist *sg,
 }
 
 #ifdef CONFIG_SBUS
-static int iounit_map_dma_area(struct device *dev, dma_addr_t *pba, unsigned long va, unsigned long addr, int len)
+static void *iounit_alloc(struct device *dev, size_t len,
+		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
 	struct iounit_struct *iounit = dev->archdata.iommu;
-	unsigned long page, end;
+	unsigned long va, addr, page, end, ret;
 	pgprot_t dvma_prot;
 	iopte_t __iomem *iopte;
 
-	*pba = addr;
+	/* XXX So what is maxphys for us and how do drivers know it? */
+	if (!len || len > 256 * 1024)
+		return NULL;
+
+	len = PAGE_ALIGN(len);
+	va = __get_free_pages(gfp, get_order(len));
+	if (!va)
+		return NULL;
+
+	addr = ret = sparc_dma_alloc_resource(dev, len);
+	if (!addr)
+		goto out_free_pages;
+	*dma_handle = addr;
 
 	dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
 	end = PAGE_ALIGN((addr + len));
@@ -237,27 +261,32 @@  static int iounit_map_dma_area(struct device *dev, dma_addr_t *pba, unsigned lon
 	flush_cache_all();
 	flush_tlb_all();
 
-	return 0;
+	return (void *)ret;
+
+out_free_pages:
+	free_pages(va, get_order(len));
+	return NULL;
 }
 
-static void iounit_unmap_dma_area(struct device *dev, unsigned long addr, int len)
+static void iounit_free(struct device *dev, size_t size, void *cpu_addr,
+		dma_addr_t dma_addr, unsigned long attrs)
 {
 	/* XXX Somebody please fill this in */
 }
 #endif
 
-static const struct sparc32_dma_ops iounit_dma_ops = {
-	.get_scsi_one		= iounit_get_scsi_one,
-	.get_scsi_sgl		= iounit_get_scsi_sgl,
-	.release_scsi_one	= iounit_release_scsi_one,
-	.release_scsi_sgl	= iounit_release_scsi_sgl,
+static const struct dma_map_ops iounit_dma_ops = {
 #ifdef CONFIG_SBUS
-	.map_dma_area		= iounit_map_dma_area,
-	.unmap_dma_area		= iounit_unmap_dma_area,
+	.alloc			= iounit_alloc,
+	.free			= iounit_free,
 #endif
+	.map_page		= iounit_map_page,
+	.unmap_page		= iounit_unmap_page,
+	.map_sg			= iounit_map_sg,
+	.unmap_sg		= iounit_unmap_sg,
 };
 
 void __init ld_mmu_iounit(void)
 {
-	sparc32_dma_ops = &iounit_dma_ops;
+	dma_ops = &iounit_dma_ops;
 }
diff --git a/arch/sparc/mm/iommu.c b/arch/sparc/mm/iommu.c
index 2c5f8a648f8c..3599485717e7 100644
--- a/arch/sparc/mm/iommu.c
+++ b/arch/sparc/mm/iommu.c
@@ -13,7 +13,7 @@ 
 #include <linux/mm.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>	/* pte_offset_map => kmap_atomic */
-#include <linux/scatterlist.h>
+#include <linux/dma-mapping.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 
@@ -205,38 +205,44 @@  static u32 iommu_get_one(struct device *dev, struct page *page, int npages)
 	return busa0;
 }
 
-static u32 iommu_get_scsi_one(struct device *dev, char *vaddr, unsigned int len)
+static dma_addr_t __sbus_iommu_map_page(struct device *dev, struct page *page,
+		unsigned long offset, size_t len)
 {
-	unsigned long off;
-	int npages;
-	struct page *page;
-	u32 busa;
-
-	off = (unsigned long)vaddr & ~PAGE_MASK;
-	npages = (off + len + PAGE_SIZE-1) >> PAGE_SHIFT;
-	page = virt_to_page((unsigned long)vaddr & PAGE_MASK);
-	busa = iommu_get_one(dev, page, npages);
-	return busa + off;
+	void *vaddr = page_address(page) + offset;
+	unsigned long off = (unsigned long)vaddr & ~PAGE_MASK;
+	unsigned long npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	
+	/* XXX So what is maxphys for us and how do drivers know it? */
+	if (!len || len > 256 * 1024)
+		return DMA_MAPPING_ERROR;
+	return iommu_get_one(dev, virt_to_page(vaddr), npages) + off;
 }
 
-static __u32 iommu_get_scsi_one_gflush(struct device *dev, char *vaddr, unsigned long len)
+static dma_addr_t sbus_iommu_map_page_gflush(struct device *dev,
+		struct page *page, unsigned long offset, size_t len,
+		enum dma_data_direction dir, unsigned long attrs)
 {
 	flush_page_for_dma(0);
-	return iommu_get_scsi_one(dev, vaddr, len);
+	return __sbus_iommu_map_page(dev, page, offset, len);
 }
 
-static __u32 iommu_get_scsi_one_pflush(struct device *dev, char *vaddr, unsigned long len)
+static dma_addr_t sbus_iommu_map_page_pflush(struct device *dev,
+		struct page *page, unsigned long offset, size_t len,
+		enum dma_data_direction dir, unsigned long attrs)
 {
-	unsigned long page = ((unsigned long) vaddr) & PAGE_MASK;
+	void *vaddr = page_address(page) + offset;
+	unsigned long p = ((unsigned long)vaddr) & PAGE_MASK;
 
-	while(page < ((unsigned long)(vaddr + len))) {
-		flush_page_for_dma(page);
-		page += PAGE_SIZE;
+	while (p < (unsigned long)vaddr + len) {
+		flush_page_for_dma(p);
+		p += PAGE_SIZE;
 	}
-	return iommu_get_scsi_one(dev, vaddr, len);
+
+	return __sbus_iommu_map_page(dev, page, offset, len);
 }
 
-static void iommu_get_scsi_sgl_gflush(struct device *dev, struct scatterlist *sg, int sz)
+static int sbus_iommu_map_sg_gflush(struct device *dev, struct scatterlist *sg,
+		int sz, enum dma_data_direction dir, unsigned long attrs)
 {
 	int n;
 
@@ -248,9 +254,12 @@  static void iommu_get_scsi_sgl_gflush(struct device *dev, struct scatterlist *sg
 		sg->dma_length = sg->length;
 		sg = sg_next(sg);
 	}
+
+	return sz;
 }
 
-static void iommu_get_scsi_sgl_pflush(struct device *dev, struct scatterlist *sg, int sz)
+static int sbus_iommu_map_sg_pflush(struct device *dev, struct scatterlist *sg,
+		int sz, enum dma_data_direction dir, unsigned long attrs)
 {
 	unsigned long page, oldpage = 0;
 	int n, i;
@@ -279,6 +288,8 @@  static void iommu_get_scsi_sgl_pflush(struct device *dev, struct scatterlist *sg
 		sg->dma_length = sg->length;
 		sg = sg_next(sg);
 	}
+
+	return sz;
 }
 
 static void iommu_release_one(struct device *dev, u32 busa, int npages)
@@ -297,23 +308,23 @@  static void iommu_release_one(struct device *dev, u32 busa, int npages)
 	bit_map_clear(&iommu->usemap, ioptex, npages);
 }
 
-static void iommu_release_scsi_one(struct device *dev, __u32 vaddr, unsigned long len)
+static void sbus_iommu_unmap_page(struct device *dev, dma_addr_t dma_addr,
+		size_t len, enum dma_data_direction dir, unsigned long attrs)
 {
-	unsigned long off;
+	unsigned long off = dma_addr & ~PAGE_MASK;
 	int npages;
 
-	off = vaddr & ~PAGE_MASK;
 	npages = (off + len + PAGE_SIZE-1) >> PAGE_SHIFT;
-	iommu_release_one(dev, vaddr & PAGE_MASK, npages);
+	iommu_release_one(dev, dma_addr & PAGE_MASK, npages);
 }
 
-static void iommu_release_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz)
+static void sbus_iommu_unmap_sg(struct device *dev, struct scatterlist *sg,
+		int sz, enum dma_data_direction dir, unsigned long attrs)
 {
 	int n;
 
 	while(sz != 0) {
 		--sz;
-
 		n = (sg->length + sg->offset + PAGE_SIZE-1) >> PAGE_SHIFT;
 		iommu_release_one(dev, sg->dma_address & PAGE_MASK, n);
 		sg->dma_address = 0x21212121;
@@ -322,15 +333,28 @@  static void iommu_release_scsi_sgl(struct device *dev, struct scatterlist *sg, i
 }
 
 #ifdef CONFIG_SBUS
-static int iommu_map_dma_area(struct device *dev, dma_addr_t *pba, unsigned long va,
-			      unsigned long addr, int len)
+static void *sbus_iommu_alloc(struct device *dev, size_t len,
+		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
 	struct iommu_struct *iommu = dev->archdata.iommu;
-	unsigned long page, end;
+	unsigned long va, addr, page, end, ret;
 	iopte_t *iopte = iommu->page_table;
 	iopte_t *first;
 	int ioptex;
 
+	/* XXX So what is maxphys for us and how do drivers know it? */
+	if (!len || len > 256 * 1024)
+		return NULL;
+
+	len = PAGE_ALIGN(len);
+	va = __get_free_pages(gfp, get_order(len));
+	if (va == 0)
+		return NULL;
+
+	addr = ret = sparc_dma_alloc_resource(dev, len);
+	if (!addr)
+		goto out_free_pages;
+
 	BUG_ON((va & ~PAGE_MASK) != 0);
 	BUG_ON((addr & ~PAGE_MASK) != 0);
 	BUG_ON((len & ~PAGE_MASK) != 0);
@@ -385,16 +409,25 @@  static int iommu_map_dma_area(struct device *dev, dma_addr_t *pba, unsigned long
 	flush_tlb_all();
 	iommu_invalidate(iommu->regs);
 
-	*pba = iommu->start + (ioptex << PAGE_SHIFT);
-	return 0;
+	*dma_handle = iommu->start + (ioptex << PAGE_SHIFT);
+	return (void *)ret;
+
+out_free_pages:
+	free_pages(va, get_order(len));
+	return NULL;
 }
 
-static void iommu_unmap_dma_area(struct device *dev, unsigned long busa, int len)
+static void sbus_iommu_free(struct device *dev, size_t len, void *cpu_addr,
+			       dma_addr_t busa, unsigned long attrs)
 {
 	struct iommu_struct *iommu = dev->archdata.iommu;
 	iopte_t *iopte = iommu->page_table;
-	unsigned long end;
+	struct page *page = virt_to_page(cpu_addr);
 	int ioptex = (busa - iommu->start) >> PAGE_SHIFT;
+	unsigned long end;
+
+	if (!sparc_dma_free_resource(cpu_addr, len))
+		return;
 
 	BUG_ON((busa & ~PAGE_MASK) != 0);
 	BUG_ON((len & ~PAGE_MASK) != 0);
@@ -408,38 +441,40 @@  static void iommu_unmap_dma_area(struct device *dev, unsigned long busa, int len
 	flush_tlb_all();
 	iommu_invalidate(iommu->regs);
 	bit_map_clear(&iommu->usemap, ioptex, len >> PAGE_SHIFT);
+
+	__free_pages(page, get_order(len));
 }
 #endif
 
-static const struct sparc32_dma_ops iommu_dma_gflush_ops = {
-	.get_scsi_one		= iommu_get_scsi_one_gflush,
-	.get_scsi_sgl		= iommu_get_scsi_sgl_gflush,
-	.release_scsi_one	= iommu_release_scsi_one,
-	.release_scsi_sgl	= iommu_release_scsi_sgl,
+static const struct dma_map_ops sbus_iommu_dma_gflush_ops = {
 #ifdef CONFIG_SBUS
-	.map_dma_area		= iommu_map_dma_area,
-	.unmap_dma_area		= iommu_unmap_dma_area,
+	.alloc			= sbus_iommu_alloc,
+	.free			= sbus_iommu_free,
 #endif
+	.map_page		= sbus_iommu_map_page_gflush,
+	.unmap_page		= sbus_iommu_unmap_page,
+	.map_sg			= sbus_iommu_map_sg_gflush,
+	.unmap_sg		= sbus_iommu_unmap_sg,
 };
 
-static const struct sparc32_dma_ops iommu_dma_pflush_ops = {
-	.get_scsi_one		= iommu_get_scsi_one_pflush,
-	.get_scsi_sgl		= iommu_get_scsi_sgl_pflush,
-	.release_scsi_one	= iommu_release_scsi_one,
-	.release_scsi_sgl	= iommu_release_scsi_sgl,
+static const struct dma_map_ops sbus_iommu_dma_pflush_ops = {
 #ifdef CONFIG_SBUS
-	.map_dma_area		= iommu_map_dma_area,
-	.unmap_dma_area		= iommu_unmap_dma_area,
+	.alloc			= sbus_iommu_alloc,
+	.free			= sbus_iommu_free,
 #endif
+	.map_page		= sbus_iommu_map_page_pflush,
+	.unmap_page		= sbus_iommu_unmap_page,
+	.map_sg			= sbus_iommu_map_sg_pflush,
+	.unmap_sg		= sbus_iommu_unmap_sg,
 };
 
 void __init ld_mmu_iommu(void)
 {
 	if (flush_page_for_dma_global) {
 		/* flush_page_for_dma flushes everything, no matter of what page is it */
-		sparc32_dma_ops = &iommu_dma_gflush_ops;
+		dma_ops = &sbus_iommu_dma_gflush_ops;
 	} else {
-		sparc32_dma_ops = &iommu_dma_pflush_ops;
+		dma_ops = &sbus_iommu_dma_pflush_ops;
 	}
 
 	if (viking_mxcc_present || srmmu_modtype == HyperSparc) {