Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6: (24 commits)
  [SPARC]: Add solaris/sunos binary support to feature removal schedule.
  [SPARC]: Merge asm-sparc{,64}/a.out.h
  [SPARC]: Merge asm-sparc{,64}/fb.h
  [SPARC]: Merge asm-sparc{,64}/errno.h
  [SPARC]: Merge asm-sparc{,64}/emergency-restart.h
  [SPARC]: Merge asm-sparc{,64}/div64.h
  [SPARC]: Merge asm-sparc{,64}/device.h
  [SPARC]: Merge asm-sparc{,64}/current.h
  [SPARC]: Merge asm-sparc{,64}/cputime.h
  [SPARC]: Merge asm-sparc{,64}/cache.h
  [SPARC]: Merge asm-sparc{,64}/byteorder.h
  [SPARC]: Merge asm-sparc{,64}/bugs.h
  [SPARC]: Merge asm-sparc{,64}/bug.h
  [SPARC]: Kill BSD errno translation table and header files.
  [SPARC]: Merge asm-sparc{,64}/bpp.h
  [SPARC]: Merge include/asm-sparc{,64}/auxvec.h
  [SPARC]: Merge include/asm-sparc{,64}/of_device.h
  [SPARC]: Merge include/asm-sparc{,64}/prom.h
  [SPARC]: Remove of_platform_device_create
  [SPARC64]: Add kretprobe support.
  ...

9 files changed, 519 insertions, 462 deletions

diff --git a/arch/sparc/kernel/errtbls.c b/arch/sparc/kernel/errtbls.c
index bb36f6eadfee..ed14df7116e9 100644
--- a/arch/sparc/kernel/errtbls.c
+++ b/arch/sparc/kernel/errtbls.c
@@ -1,21 +1,18 @@
-/* $Id: errtbls.c,v 1.2 1995/11/25 00:57:55 davem Exp $
- * errtbls.c: Error number conversion tables between various syscall
- *            OS semantics.
+/* errtbls.c: Error number conversion tables.
  *
- * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1995, 2007 David S. Miller (davem@davemloft.net)
  *
  * Based upon preliminary work which is:
  *
  * Copyright (C) 1995 Adrian M. Rodriguez (adrian@remus.rutgers.edu)
  */
 
-#include <asm/bsderrno.h>        /* NetBSD (bsd4.4) errnos */
 #include <asm/solerrno.h>        /* Solaris errnos */
 
-/* Here are tables which convert between Linux/SunOS error number
- * values to the equivalent in other OSs.  Note that since the Linux
- * ones have been set up to match exactly those of SunOS, no
- * translation table is needed for that OS.
+/* Here is the table which converts between Linux error number values
+ * to the equivalent under Solaris.  Note that since the Linux ones
+ * have been set up to match exactly those of SunOS, no translation
+ * table is needed for that OS.
  */
 
 int solaris_errno[] = {
@@ -145,132 +142,3 @@ int solaris_errno[] = {
 	SOL_ELIBMAX,
 	SOL_ELIBSCN,
 };
-
-int netbsd_errno[] = {
-	0,
-	BSD_EPERM,
-	BSD_ENOENT,
-	BSD_ESRCH,
-	BSD_EINTR,
-	BSD_EIO,
-	BSD_ENXIO,
-	BSD_E2BIG,
-	BSD_ENOEXEC,
-	BSD_EBADF,
-	BSD_ECHILD,
-	BSD_EAGAIN,
-	BSD_ENOMEM,
-	BSD_EACCES,
-	BSD_EFAULT,
-	BSD_NOTBLK,
-	BSD_EBUSY,
-	BSD_EEXIST,
-	BSD_EXDEV,
-	BSD_ENODEV,
-	BSD_ENOTDIR,
-	BSD_EISDIR,
-	BSD_EINVAL,
-	BSD_ENFILE,
-	BSD_EMFILE,
-	BSD_ENOTTY,
-	BSD_ETXTBSY,
-	BSD_EFBIG,
-	BSD_ENOSPC,
-	BSD_ESPIPE,
-	BSD_EROFS,
-	BSD_EMLINK,
-	BSD_EPIPE,
-	BSD_EDOM,
-	BSD_ERANGE,
-	BSD_EWOULDBLOCK,
-	BSD_EINPROGRESS,
-	BSD_EALREADY,
-	BSD_ENOTSOCK,
-	BSD_EDESTADDRREQ,
-	BSD_EMSGSIZE,
-	BSD_EPROTOTYPE,
-	BSD_ENOPROTOOPT,
-	BSD_EPROTONOSUPPORT,
-	BSD_ESOCKTNOSUPPORT,
-	BSD_EOPNOTSUPP,
-	BSD_EPFNOSUPPORT,
-	BSD_EAFNOSUPPORT,
-	BSD_EADDRINUSE,
-	BSD_EADDRNOTAVAIL,
-	BSD_ENETDOWN,
-	BSD_ENETUNREACH,
-	BSD_ENETRESET,
-	BSD_ECONNABORTED,
-	BSD_ECONNRESET,
-	BSD_ENOBUFS,
-	BSD_EISCONN,
-	BSD_ENOTONN,
-	BSD_ESHUTDOWN,
-	BSD_ETOOMANYREFS,
-	BSD_ETIMEDOUT,
-	BSD_ECONNREFUSED,
-	BSD_ELOOP,
-	BSD_ENAMETOOLONG,
-	BSD_EHOSTDOWN,
-	BSD_EHOSTUNREACH,
-	BSD_ENOTEMPTY,
-	BSD_EPROCLIM,
-	BSD_EUSERS,
-	BSD_EDQUOT,
-	BSD_ESTALE,
-	BSD_EREMOTE,
-	BSD_ENOSTR,
-	BSD_ETIME,
-	BSD_ENOSR,
-	BSD_ENOMSG,
-	BSD_EBADMSG,
-	BSD_IDRM,
-	BSD_EDEADLK,
-	BSD_ENOLCK,
-	BSD_ENONET,
-	BSD_ERREMOTE,
-	BSD_ENOLINK,
-	BSD_EADV,
-	BSD_ESRMNT,
-	BSD_ECOMM,
-	BSD_EPROTO,
-	BSD_EMULTIHOP,
-	BSD_EINVAL,    /* EDOTDOT XXX??? */
-	BSD_REMCHG,
-	BSD_NOSYS,
-	BSD_STRPIPE,
-	BSD_EOVERFLOW,
-	BSD_EBADFD,
-	BSD_ECHRNG,
-	BSD_EL2NSYNC,
-	BSD_EL3HLT,
-	BSD_EL3RST,
-	BSD_NRNG,
-	BSD_EUNATCH,
-	BSD_ENOCSI,
-	BSD_EL2HLT,
-	BSD_EBADE,
-	BSD_EBADR,
-	BSD_EXFULL,
-	BSD_ENOANO,
-	BSD_EBADRQC,
-	BSD_EBADSLT,
-	BSD_EDEADLOCK,
-	BSD_EBFONT,
-	BSD_ELIBEXEC,
-	BSD_ENODATA,
-	BSD_ELIBBAD,
-	BSD_ENOPKG,
-	BSD_ELIBACC,
-	BSD_ENOTUNIQ,
-	BSD_ERESTART,
-	BSD_EUCLEAN,
-	BSD_ENOTNAM,
-	BSD_ENAVAIL,
-	BSD_EISNAM,
-	BSD_EREMOTEIO,
-	BSD_EILSEQ,
-	BSD_ELIBMAX,
-	BSD_ELIBSCN,
-};
-
diff --git a/arch/sparc/kernel/of_device.c b/arch/sparc/kernel/of_device.c
index 3ea000d15e3a..cc4c235c4f59 100644
--- a/arch/sparc/kernel/of_device.c
+++ b/arch/sparc/kernel/of_device.c
@@ -584,30 +584,3 @@ static int __init of_debug(char *str)
 }
 
 __setup("of_debug=", of_debug);
-
-struct of_device* of_platform_device_create(struct device_node *np,
-					    const char *bus_id,
-					    struct device *parent,
-					    struct bus_type *bus)
-{
-	struct of_device *dev;
-
-	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
-	if (!dev)
-		return NULL;
-
-	dev->dev.parent = parent;
-	dev->dev.bus = bus;
-	dev->dev.release = of_release_dev;
-
-	strlcpy(dev->dev.bus_id, bus_id, BUS_ID_SIZE);
-
-	if (of_device_register(dev) != 0) {
-		kfree(dev);
-		return NULL;
-	}
-
-	return dev;
-}
-
-EXPORT_SYMBOL(of_platform_device_create);
diff --git a/arch/sparc/kernel/vmlinux.lds.S b/arch/sparc/kernel/vmlinux.lds.S
index 216147d6e61f..b1002c607196 100644
--- a/arch/sparc/kernel/vmlinux.lds.S
+++ b/arch/sparc/kernel/vmlinux.lds.S
@@ -89,6 +89,10 @@ SECTIONS
 	.data.cacheline_aligned : {
 		*(.data.cacheline_aligned)
 	}
+	. = ALIGN(32);
+	.data.read_mostly : {
+		*(.data.read_mostly)
+	}
 
 	__bss_start = .;
 	.sbss : {
diff --git a/arch/sparc64/Kconfig b/arch/sparc64/Kconfig
index 810755637311..3af378ddb6ae 100644
--- a/arch/sparc64/Kconfig
+++ b/arch/sparc64/Kconfig
@@ -41,6 +41,10 @@ config MMU
 	bool
 	default y
 
+config IOMMU_HELPER
+	bool
+	default y
+
 config QUICKLIST
 	bool
 	default y
diff --git a/arch/sparc64/kernel/iommu.c b/arch/sparc64/kernel/iommu.c
index 5623a4d59dff..d3276ebcfb47 100644
--- a/arch/sparc64/kernel/iommu.c
+++ b/arch/sparc64/kernel/iommu.c
@@ -1,6 +1,6 @@
 /* iommu.c: Generic sparc64 IOMMU support.
  *
- * Copyright (C) 1999, 2007 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 1999, 2007, 2008 David S. Miller (davem@davemloft.net)
  * Copyright (C) 1999, 2000 Jakub Jelinek (jakub@redhat.com)
  */
 
@@ -10,6 +10,7 @@
 #include <linux/device.h>
 #include <linux/dma-mapping.h>
 #include <linux/errno.h>
+#include <linux/iommu-helper.h>
 
 #ifdef CONFIG_PCI
 #include <linux/pci.h>
@@ -41,7 +42,7 @@
 			       "i" (ASI_PHYS_BYPASS_EC_E))
 
 /* Must be invoked under the IOMMU lock. */
-static void __iommu_flushall(struct iommu *iommu)
+static void iommu_flushall(struct iommu *iommu)
 {
 	if (iommu->iommu_flushinv) {
 		iommu_write(iommu->iommu_flushinv, ~(u64)0);
@@ -83,54 +84,91 @@ static inline void iopte_make_dummy(struct iommu *iommu, iopte_t *iopte)
 	iopte_val(*iopte) = val;
 }
 
-/* Based largely upon the ppc64 iommu allocator.  */
-static long arena_alloc(struct iommu *iommu, unsigned long npages)
+/* Based almost entirely upon the ppc64 iommu allocator.  If you use the 'handle'
+ * facility it must all be done in one pass while under the iommu lock.
+ *
+ * On sun4u platforms, we only flush the IOMMU once every time we've passed
+ * over the entire page table doing allocations.  Therefore we only ever advance
+ * the hint and cannot backtrack it.
+ */
+unsigned long iommu_range_alloc(struct device *dev,
+				struct iommu *iommu,
+				unsigned long npages,
+				unsigned long *handle)
 {
+	unsigned long n, end, start, limit, boundary_size;
 	struct iommu_arena *arena = &iommu->arena;
-	unsigned long n, i, start, end, limit;
-	int pass;
+	int pass = 0;
+
+	/* This allocator was derived from x86_64's bit string search */
+
+	/* Sanity check */
+	if (unlikely(npages == 0)) {
+		if (printk_ratelimit())
+			WARN_ON(1);
+		return DMA_ERROR_CODE;
+	}
+
+	if (handle && *handle)
+		start = *handle;
+	else
+		start = arena->hint;
 
 	limit = arena->limit;
-	start = arena->hint;
-	pass = 0;
 
-again:
-	n = find_next_zero_bit(arena->map, limit, start);
-	end = n + npages;
-	if (unlikely(end >= limit)) {
+	/* The case below can happen if we have a small segment appended
+	 * to a large, or when the previous alloc was at the very end of
+	 * the available space. If so, go back to the beginning and flush.
+	 */
+	if (start >= limit) {
+		start = 0;
+		if (iommu->flush_all)
+			iommu->flush_all(iommu);
+	}
+
+ again:
+
+	if (dev)
+		boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1,
+				      1 << IO_PAGE_SHIFT);
+	else
+		boundary_size = ALIGN(1UL << 32, 1 << IO_PAGE_SHIFT);
+
+	n = iommu_area_alloc(arena->map, limit, start, npages, 0,
+			     boundary_size >> IO_PAGE_SHIFT, 0);
+	if (n == -1) {
 		if (likely(pass < 1)) {
-			limit = start;
+			/* First failure, rescan from the beginning.  */
 			start = 0;
-			__iommu_flushall(iommu);
+			if (iommu->flush_all)
+				iommu->flush_all(iommu);
 			pass++;
 			goto again;
 		} else {
-			/* Scanned the whole thing, give up. */
-			return -1;
-		}
-	}
-
-	for (i = n; i < end; i++) {
-		if (test_bit(i, arena->map)) {
-			start = i + 1;
-			goto again;
+			/* Second failure, give up */
+			return DMA_ERROR_CODE;
 		}
 	}
 
-	for (i = n; i < end; i++)
-		__set_bit(i, arena->map);
+	end = n + npages;
 
 	arena->hint = end;
 
+	/* Update handle for SG allocations */
+	if (handle)
+		*handle = end;
+
 	return n;
 }
 
-static void arena_free(struct iommu_arena *arena, unsigned long base, unsigned long npages)
+void iommu_range_free(struct iommu *iommu, dma_addr_t dma_addr, unsigned long npages)
 {
-	unsigned long i;
+	struct iommu_arena *arena = &iommu->arena;
+	unsigned long entry;
 
-	for (i = base; i < (base + npages); i++)
-		__clear_bit(i, arena->map);
+	entry = (dma_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT;
+
+	iommu_area_free(arena->map, entry, npages);
 }
 
 int iommu_table_init(struct iommu *iommu, int tsbsize,
@@ -156,6 +194,9 @@ int iommu_table_init(struct iommu *iommu, int tsbsize,
 	}
 	iommu->arena.limit = num_tsb_entries;
 
+	if (tlb_type != hypervisor)
+		iommu->flush_all = iommu_flushall;
+
 	/* Allocate and initialize the dummy page which we
 	 * set inactive IO PTEs to point to.
 	 */
@@ -192,22 +233,18 @@ out_free_map:
 	return -ENOMEM;
 }
 
-static inline iopte_t *alloc_npages(struct iommu *iommu, unsigned long npages)
+static inline iopte_t *alloc_npages(struct device *dev, struct iommu *iommu,
+				    unsigned long npages)
 {
-	long entry;
+	unsigned long entry;
 
-	entry = arena_alloc(iommu, npages);
-	if (unlikely(entry < 0))
+	entry = iommu_range_alloc(dev, iommu, npages, NULL);
+	if (unlikely(entry == DMA_ERROR_CODE))
 		return NULL;
 
 	return iommu->page_table + entry;
 }
 
-static inline void free_npages(struct iommu *iommu, dma_addr_t base, unsigned long npages)
-{
-	arena_free(&iommu->arena, base >> IO_PAGE_SHIFT, npages);
-}
-
 static int iommu_alloc_ctx(struct iommu *iommu)
 {
 	int lowest = iommu->ctx_lowest_free;
@@ -258,7 +295,7 @@ static void *dma_4u_alloc_coherent(struct device *dev, size_t size,
 	iommu = dev->archdata.iommu;
 
 	spin_lock_irqsave(&iommu->lock, flags);
-	iopte = alloc_npages(iommu, size >> IO_PAGE_SHIFT);
+	iopte = alloc_npages(dev, iommu, size >> IO_PAGE_SHIFT);
 	spin_unlock_irqrestore(&iommu->lock, flags);
 
 	if (unlikely(iopte == NULL)) {
@@ -296,7 +333,7 @@ static void dma_4u_free_coherent(struct device *dev, size_t size,
 
 	spin_lock_irqsave(&iommu->lock, flags);
 
-	free_npages(iommu, dvma - iommu->page_table_map_base, npages);
+	iommu_range_free(iommu, dvma, npages);
 
 	spin_unlock_irqrestore(&iommu->lock, flags);
 
@@ -327,7 +364,7 @@ static dma_addr_t dma_4u_map_single(struct device *dev, void *ptr, size_t sz,
 	npages >>= IO_PAGE_SHIFT;
 
 	spin_lock_irqsave(&iommu->lock, flags);
-	base = alloc_npages(iommu, npages);
+	base = alloc_npages(dev, iommu, npages);
 	ctx = 0;
 	if (iommu->iommu_ctxflush)
 		ctx = iommu_alloc_ctx(iommu);
@@ -465,7 +502,7 @@ static void dma_4u_unmap_single(struct device *dev, dma_addr_t bus_addr,
 	for (i = 0; i < npages; i++)
 		iopte_make_dummy(iommu, base + i);
 
-	free_npages(iommu, bus_addr - iommu->page_table_map_base, npages);
+	iommu_range_free(iommu, bus_addr, npages);
 
 	iommu_free_ctx(iommu, ctx);
 
@@ -475,124 +512,209 @@ static void dma_4u_unmap_single(struct device *dev, dma_addr_t bus_addr,
 static int dma_4u_map_sg(struct device *dev, struct scatterlist *sglist,
 			 int nelems, enum dma_data_direction direction)
 {
-	unsigned long flags, ctx, i, npages, iopte_protection;
-	struct scatterlist *sg;
+	struct scatterlist *s, *outs, *segstart;
+	unsigned long flags, handle, prot, ctx;
+	dma_addr_t dma_next = 0, dma_addr;
+	unsigned int max_seg_size;
+	int outcount, incount, i;
 	struct strbuf *strbuf;
 	struct iommu *iommu;
-	iopte_t *base;
-	u32 dma_base;
-
-	/* Fast path single entry scatterlists. */
-	if (nelems == 1) {
-		sglist->dma_address =
-			dma_4u_map_single(dev, sg_virt(sglist),
-					  sglist->length, direction);
-		if (unlikely(sglist->dma_address == DMA_ERROR_CODE))
-			return 0;
-		sglist->dma_length = sglist->length;
-		return 1;
-	}
+
+	BUG_ON(direction == DMA_NONE);
 
 	iommu = dev->archdata.iommu;
 	strbuf = dev->archdata.stc;
-
-	if (unlikely(direction == DMA_NONE))
-		goto bad_no_ctx;
-
-	npages = calc_npages(sglist, nelems);
+	if (nelems == 0 || !iommu)
+		return 0;
 
 	spin_lock_irqsave(&iommu->lock, flags);
 
-	base = alloc_npages(iommu, npages);
 	ctx = 0;
 	if (iommu->iommu_ctxflush)
 		ctx = iommu_alloc_ctx(iommu);
 
-	spin_unlock_irqrestore(&iommu->lock, flags);
-
-	if (base == NULL)
-		goto bad;
-
-	dma_base = iommu->page_table_map_base +
-		((base - iommu->page_table) << IO_PAGE_SHIFT);
-
 	if (strbuf->strbuf_enabled)
-		iopte_protection = IOPTE_STREAMING(ctx);
+		prot = IOPTE_STREAMING(ctx);
 	else
-		iopte_protection = IOPTE_CONSISTENT(ctx);
+		prot = IOPTE_CONSISTENT(ctx);
 	if (direction != DMA_TO_DEVICE)
-		iopte_protection |= IOPTE_WRITE;
-
-	for_each_sg(sglist, sg, nelems, i) {
-		unsigned long paddr = SG_ENT_PHYS_ADDRESS(sg);
-		unsigned long slen = sg->length;
-		unsigned long this_npages;
+		prot |= IOPTE_WRITE;
+
+	outs = s = segstart = &sglist[0];
+	outcount = 1;
+	incount = nelems;
+	handle = 0;
+
+	/* Init first segment length for backout at failure */
+	outs->dma_length = 0;
+
+	max_seg_size = dma_get_max_seg_size(dev);
+	for_each_sg(sglist, s, nelems, i) {
+		unsigned long paddr, npages, entry, slen;
+		iopte_t *base;
+
+		slen = s->length;
+		/* Sanity check */
+		if (slen == 0) {
+			dma_next = 0;
+			continue;
+		}
+		/* Allocate iommu entries for that segment */
+		paddr = (unsigned long) SG_ENT_PHYS_ADDRESS(s);
+		npages = iommu_num_pages(paddr, slen);
+		entry = iommu_range_alloc(dev, iommu, npages, &handle);
+
+		/* Handle failure */
+		if (unlikely(entry == DMA_ERROR_CODE)) {
+			if (printk_ratelimit())
+				printk(KERN_INFO "iommu_alloc failed, iommu %p paddr %lx"
+				       " npages %lx\n", iommu, paddr, npages);
+			goto iommu_map_failed;
+		}
 
-		this_npages = iommu_num_pages(paddr, slen);
+		base = iommu->page_table + entry;
 
-		sg->dma_address = dma_base | (paddr & ~IO_PAGE_MASK);
-		sg->dma_length = slen;
+		/* Convert entry to a dma_addr_t */
+		dma_addr = iommu->page_table_map_base +
+			(entry << IO_PAGE_SHIFT);
+		dma_addr |= (s->offset & ~IO_PAGE_MASK);
 
+		/* Insert into HW table */
 		paddr &= IO_PAGE_MASK;
-		while (this_npages--) {
-			iopte_val(*base) = iopte_protection | paddr;
-
+		while (npages--) {
+			iopte_val(*base) = prot | paddr;
 			base++;
 			paddr += IO_PAGE_SIZE;
-			dma_base += IO_PAGE_SIZE;
 		}
+
+		/* If we are in an open segment, try merging */
+		if (segstart != s) {
+			/* We cannot merge if:
+			 * - allocated dma_addr isn't contiguous to previous allocation
+			 */
+			if ((dma_addr != dma_next) ||
+			    (outs->dma_length + s->length > max_seg_size)) {
+				/* Can't merge: create a new segment */
+				segstart = s;
+				outcount++;
+				outs = sg_next(outs);
+			} else {
+				outs->dma_length += s->length;
+			}
+		}
+
+		if (segstart == s) {
+			/* This is a new segment, fill entries */
+			outs->dma_address = dma_addr;
+			outs->dma_length = slen;
+		}
+
+		/* Calculate next page pointer for contiguous check */
+		dma_next = dma_addr + slen;
 	}
 
-	return nelems;
+	spin_unlock_irqrestore(&iommu->lock, flags);
+
+	if (outcount < incount) {
+		outs = sg_next(outs);
+		outs->dma_address = DMA_ERROR_CODE;
+		outs->dma_length = 0;
+	}
+
+	return outcount;
+
+iommu_map_failed:
+	for_each_sg(sglist, s, nelems, i) {
+		if (s->dma_length != 0) {
+			unsigned long vaddr, npages, entry, i;
+			iopte_t *base;
+
+			vaddr = s->dma_address & IO_PAGE_MASK;
+			npages = iommu_num_pages(s->dma_address, s->dma_length);
+			iommu_range_free(iommu, vaddr, npages);
+
+			entry = (vaddr - iommu->page_table_map_base)
+				>> IO_PAGE_SHIFT;
+			base = iommu->page_table + entry;
+
+			for (i = 0; i < npages; i++)
+				iopte_make_dummy(iommu, base + i);
+
+			s->dma_address = DMA_ERROR_CODE;
+			s->dma_length = 0;
+		}
+		if (s == outs)
+			break;
+	}
+	spin_unlock_irqrestore(&iommu->lock, flags);
 
-bad:
-	iommu_free_ctx(iommu, ctx);
-bad_no_ctx:
-	if (printk_ratelimit())
-		WARN_ON(1);
 	return 0;
 }
 
+/* If contexts are being used, they are the same in all of the mappings
+ * we make for a particular SG.
+ */
+static unsigned long fetch_sg_ctx(struct iommu *iommu, struct scatterlist *sg)
+{
+	unsigned long ctx = 0;
+
+	if (iommu->iommu_ctxflush) {
+		iopte_t *base;
+		u32 bus_addr;
+
+		bus_addr = sg->dma_address & IO_PAGE_MASK;
+		base = iommu->page_table +
+			((bus_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT);
+
+		ctx = (iopte_val(*base) & IOPTE_CONTEXT) >> 47UL;
+	}
+	return ctx;
+}
+
 static void dma_4u_unmap_sg(struct device *dev, struct scatterlist *sglist,
 			    int nelems, enum dma_data_direction direction)
 {
-	unsigned long flags, ctx, i, npages;
+	unsigned long flags, ctx;
+	struct scatterlist *sg;
 	struct strbuf *strbuf;
 	struct iommu *iommu;
-	iopte_t *base;
-	u32 bus_addr;
 
-	if (unlikely(direction == DMA_NONE)) {
-		if (printk_ratelimit())
-			WARN_ON(1);
-	}
+	BUG_ON(direction == DMA_NONE);
 
 	iommu = dev->archdata.iommu;
 	strbuf = dev->archdata.stc;
 
-	bus_addr = sglist->dma_address & IO_PAGE_MASK;
+	ctx = fetch_sg_ctx(iommu, sglist);
 
-	npages = calc_npages(sglist, nelems);
+	spin_lock_irqsave(&iommu->lock, flags);
 
-	base = iommu->page_table +
-		((bus_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT);
+	sg = sglist;
+	while (nelems--) {
+		dma_addr_t dma_handle = sg->dma_address;
+		unsigned int len = sg->dma_length;
+		unsigned long npages, entry;
+		iopte_t *base;
+		int i;
 
-	spin_lock_irqsave(&iommu->lock, flags);
+		if (!len)
+			break;
+		npages = iommu_num_pages(dma_handle, len);
+		iommu_range_free(iommu, dma_handle, npages);
 
-	/* Record the context, if any. */
-	ctx = 0;
-	if (iommu->iommu_ctxflush)
-		ctx = (iopte_val(*base) & IOPTE_CONTEXT) >> 47UL;
+		entry = ((dma_handle - iommu->page_table_map_base)
+			 >> IO_PAGE_SHIFT);
+		base = iommu->page_table + entry;
 
-	/* Step 1: Kick data out of streaming buffers if necessary. */
-	if (strbuf->strbuf_enabled)
-		strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction);
+		dma_handle &= IO_PAGE_MASK;
+		if (strbuf->strbuf_enabled)
+			strbuf_flush(strbuf, iommu, dma_handle, ctx,
+				     npages, direction);
 
-	/* Step 2: Clear out the TSB entries. */
-	for (i = 0; i < npages; i++)
-		iopte_make_dummy(iommu, base + i);
+		for (i = 0; i < npages; i++)
+			iopte_make_dummy(iommu, base + i);
 
-	free_npages(iommu, bus_addr - iommu->page_table_map_base, npages);
+		sg = sg_next(sg);
+	}
 
 	iommu_free_ctx(iommu, ctx);
 
diff --git a/arch/sparc64/kernel/iommu_common.h b/arch/sparc64/kernel/iommu_common.h
index 4b5cafa2877a..0713bd58499c 100644
--- a/arch/sparc64/kernel/iommu_common.h
+++ b/arch/sparc64/kernel/iommu_common.h
@@ -1,9 +1,11 @@
-/* $Id: iommu_common.h,v 1.5 2001/12/11 09:41:01 davem Exp $
- * iommu_common.h: UltraSparc SBUS/PCI common iommu declarations.
+/* iommu_common.h: UltraSparc SBUS/PCI common iommu declarations.
  *
- * Copyright (C) 1999 David S. Miller (davem@redhat.com)
+ * Copyright (C) 1999, 2008 David S. Miller (davem@davemloft.net)
  */
 
+#ifndef _IOMMU_COMMON_H
+#define _IOMMU_COMMON_H
+
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/sched.h>
@@ -56,21 +58,12 @@ static inline unsigned long calc_npages(struct scatterlist *sglist, int nelems)
 	return npages;
 }
 
-/* You are _strongly_ advised to enable the following debugging code
- * any time you make changes to the sg code below, run it for a while
- * with filesystems mounted read-only before buying the farm... -DaveM
- */
-#undef VERIFY_SG
-
-#ifdef VERIFY_SG
-extern void verify_sglist(struct scatterlist *sg, int nents, iopte_t *iopte, int npages);
-#endif
-
-/* Two addresses are "virtually contiguous" if and only if:
- * 1) They are equal, or...
- * 2) They are both on a page boundary
- */
-#define VCONTIG(__X, __Y)	(((__X) == (__Y)) || \
-				 (((__X) | (__Y)) << (64UL - PAGE_SHIFT)) == 0UL)
+extern unsigned long iommu_range_alloc(struct device *dev,
+				       struct iommu *iommu,
+				       unsigned long npages,
+				       unsigned long *handle);
+extern void iommu_range_free(struct iommu *iommu,
+			     dma_addr_t dma_addr,
+			     unsigned long npages);
 
-extern unsigned long prepare_sg(struct device *dev, struct scatterlist *sg, int nents);
+#endif /* _IOMMU_COMMON_H */
diff --git a/arch/sparc64/kernel/kprobes.c b/arch/sparc64/kernel/kprobes.c
index d94f901d321e..34fc3ddd5002 100644
--- a/arch/sparc64/kernel/kprobes.c
+++ b/arch/sparc64/kernel/kprobes.c
@@ -480,8 +480,117 @@ int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
 	return 0;
 }
 
-/* architecture specific initialization */
-int arch_init_kprobes(void)
+/* Called with kretprobe_lock held.  The value stored in the return
+ * address register is actually 2 instructions before where the
+ * callee will return to.  Sequences usually look something like this
+ *
+ *		call	some_function	<--- return register points here
+ *		 nop			<--- call delay slot
+ *		whatever		<--- where callee returns to
+ *
+ * To keep trampoline_probe_handler logic simpler, we normalize the
+ * value kept in ri->ret_addr so we don't need to keep adjusting it
+ * back and forth.
+ */
+void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
+				      struct pt_regs *regs)
+{
+	ri->ret_addr = (kprobe_opcode_t *)(regs->u_regs[UREG_RETPC] + 8);
+
+	/* Replace the return addr with trampoline addr */
+	regs->u_regs[UREG_RETPC] =
+		((unsigned long)kretprobe_trampoline) - 8;
+}
+
+/*
+ * Called when the probe at kretprobe trampoline is hit
+ */
+int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
+{
+	struct kretprobe_instance *ri = NULL;
+	struct hlist_head *head, empty_rp;
+	struct hlist_node *node, *tmp;
+	unsigned long flags, orig_ret_address = 0;
+	unsigned long trampoline_address =(unsigned long)&kretprobe_trampoline;
+
+	INIT_HLIST_HEAD(&empty_rp);
+	spin_lock_irqsave(&kretprobe_lock, flags);
+	head = kretprobe_inst_table_head(current);
+
+	/*
+	 * It is possible to have multiple instances associated with a given
+	 * task either because an multiple functions in the call path
+	 * have a return probe installed on them, and/or more then one return
+	 * return probe was registered for a target function.
+	 *
+	 * We can handle this because:
+	 *     - instances are always inserted at the head of the list
+	 *     - when multiple return probes are registered for the same
+	 *       function, the first instance's ret_addr will point to the
+	 *       real return address, and all the rest will point to
+	 *       kretprobe_trampoline
+	 */
+	hlist_for_each_entry_safe(ri, node, tmp, head, hlist) {
+		if (ri->task != current)
+			/* another task is sharing our hash bucket */
+			continue;
+
+		if (ri->rp && ri->rp->handler)
+			ri->rp->handler(ri, regs);
+
+		orig_ret_address = (unsigned long)ri->ret_addr;
+		recycle_rp_inst(ri, &empty_rp);
+
+		if (orig_ret_address != trampoline_address)
+			/*
+			 * This is the real return address. Any other
+			 * instances associated with this task are for
+			 * other calls deeper on the call stack
+			 */
+			break;
+	}
+
+	kretprobe_assert(ri, orig_ret_address, trampoline_address);
+	regs->tpc = orig_ret_address;
+	regs->tnpc = orig_ret_address + 4;
+
+	reset_current_kprobe();
+	spin_unlock_irqrestore(&kretprobe_lock, flags);
+	preempt_enable_no_resched();
+
+	hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) {
+		hlist_del(&ri->hlist);
+		kfree(ri);
+	}
+	/*
+	 * By returning a non-zero value, we are telling
+	 * kprobe_handler() that we don't want the post_handler
+	 * to run (and have re-enabled preemption)
+	 */
+	return 1;
+}
+
+void kretprobe_trampoline_holder(void)
+{
+	asm volatile(".global kretprobe_trampoline\n"
+		     "kretprobe_trampoline:\n"
+		     "\tnop\n"
+		     "\tnop\n");
+}
+static struct kprobe trampoline_p = {
+	.addr = (kprobe_opcode_t *) &kretprobe_trampoline,
+	.pre_handler = trampoline_probe_handler
+};
+
+int __init arch_init_kprobes(void)
 {
+	return register_kprobe(&trampoline_p);
+}
+
+int __kprobes arch_trampoline_kprobe(struct kprobe *p)
+{
+	if (p->addr == (kprobe_opcode_t *)&kretprobe_trampoline)
+		return 1;
+
 	return 0;
 }
diff --git a/arch/sparc64/kernel/of_device.c b/arch/sparc64/kernel/of_device.c
index fc5c0cc793b8..0fd9db95b896 100644
--- a/arch/sparc64/kernel/of_device.c
+++ b/arch/sparc64/kernel/of_device.c
@@ -868,29 +868,3 @@ static int __init of_debug(char *str)
 }
 
 __setup("of_debug=", of_debug);
-
-struct of_device* of_platform_device_create(struct device_node *np,
-					    const char *bus_id,
-					    struct device *parent,
-					    struct bus_type *bus)
-{
-	struct of_device *dev;
-
-	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
-	if (!dev)
-		return NULL;
-
-	dev->dev.parent = parent;
-	dev->dev.bus = bus;
-	dev->dev.release = of_release_dev;
-
-	strlcpy(dev->dev.bus_id, bus_id, BUS_ID_SIZE);
-
-	if (of_device_register(dev) != 0) {
-		kfree(dev);
-		return NULL;
-	}
-
-	return dev;
-}
-EXPORT_SYMBOL(of_platform_device_create);
diff --git a/arch/sparc64/kernel/pci_sun4v.c b/arch/sparc64/kernel/pci_sun4v.c
index 61baf8dc095e..ddca6c6c0b49 100644
--- a/arch/sparc64/kernel/pci_sun4v.c
+++ b/arch/sparc64/kernel/pci_sun4v.c
@@ -1,6 +1,6 @@
 /* pci_sun4v.c: SUN4V specific PCI controller support.
  *
- * Copyright (C) 2006, 2007 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 2006, 2007, 2008 David S. Miller (davem@davemloft.net)
  */
 
 #include <linux/kernel.h>
@@ -89,6 +89,17 @@ static long iommu_batch_flush(struct iommu_batch *p)
 	return 0;
 }
 
+static inline void iommu_batch_new_entry(unsigned long entry)
+{
+	struct iommu_batch *p = &__get_cpu_var(iommu_batch);
+
+	if (p->entry + p->npages == entry)
+		return;
+	if (p->entry != ~0UL)
+		iommu_batch_flush(p);
+	p->entry = entry;
+}
+
 /* Interrupts must be disabled.  */
 static inline long iommu_batch_add(u64 phys_page)
 {
@@ -113,54 +124,6 @@ static inline long iommu_batch_end(void)
 	return iommu_batch_flush(p);
 }
 
-static long arena_alloc(struct iommu_arena *arena, unsigned long npages)
-{
-	unsigned long n, i, start, end, limit;
-	int pass;
-
-	limit = arena->limit;
-	start = arena->hint;
-	pass = 0;
-
-again:
-	n = find_next_zero_bit(arena->map, limit, start);
-	end = n + npages;
-	if (unlikely(end >= limit)) {
-		if (likely(pass < 1)) {
-			limit = start;
-			start = 0;
-			pass++;
-			goto again;
-		} else {
-			/* Scanned the whole thing, give up. */
-			return -1;
-		}
-	}
-
-	for (i = n; i < end; i++) {
-		if (test_bit(i, arena->map)) {
-			start = i + 1;
-			goto again;
-		}
-	}
-
-	for (i = n; i < end; i++)
-		__set_bit(i, arena->map);
-
-	arena->hint = end;
-
-	return n;
-}
-
-static void arena_free(struct iommu_arena *arena, unsigned long base,
-		       unsigned long npages)
-{
-	unsigned long i;
-
-	for (i = base; i < (base + npages); i++)
-		__clear_bit(i, arena->map);
-}
-
 static void *dma_4v_alloc_coherent(struct device *dev, size_t size,
 				   dma_addr_t *dma_addrp, gfp_t gfp)
 {
@@ -185,11 +148,11 @@ static void *dma_4v_alloc_coherent(struct device *dev, size_t size,
 	iommu = dev->archdata.iommu;
 
 	spin_lock_irqsave(&iommu->lock, flags);
-	entry = arena_alloc(&iommu->arena, npages);
+	entry = iommu_range_alloc(dev, iommu, npages, NULL);
 	spin_unlock_irqrestore(&iommu->lock, flags);
 
-	if (unlikely(entry < 0L))
-		goto arena_alloc_fail;
+	if (unlikely(entry == DMA_ERROR_CODE))
+		goto range_alloc_fail;
 
 	*dma_addrp = (iommu->page_table_map_base +
 		      (entry << IO_PAGE_SHIFT));
@@ -219,10 +182,10 @@ static void *dma_4v_alloc_coherent(struct device *dev, size_t size,
 iommu_map_fail:
 	/* Interrupts are disabled.  */
 	spin_lock(&iommu->lock);
-	arena_free(&iommu->arena, entry, npages);
+	iommu_range_free(iommu, *dma_addrp, npages);
 	spin_unlock_irqrestore(&iommu->lock, flags);
 
-arena_alloc_fail:
+range_alloc_fail:
 	free_pages(first_page, order);
 	return NULL;
 }
@@ -243,7 +206,7 @@ static void dma_4v_free_coherent(struct device *dev, size_t size, void *cpu,
 
 	spin_lock_irqsave(&iommu->lock, flags);
 
-	arena_free(&iommu->arena, entry, npages);
+	iommu_range_free(iommu, dvma, npages);
 
 	do {
 		unsigned long num;
@@ -281,10 +244,10 @@ static dma_addr_t dma_4v_map_single(struct device *dev, void *ptr, size_t sz,
 	npages >>= IO_PAGE_SHIFT;
 
 	spin_lock_irqsave(&iommu->lock, flags);
-	entry = arena_alloc(&iommu->arena, npages);
+	entry = iommu_range_alloc(dev, iommu, npages, NULL);
 	spin_unlock_irqrestore(&iommu->lock, flags);
 
-	if (unlikely(entry < 0L))
+	if (unlikely(entry == DMA_ERROR_CODE))
 		goto bad;
 
 	bus_addr = (iommu->page_table_map_base +
@@ -319,7 +282,7 @@ bad:
 iommu_map_fail:
 	/* Interrupts are disabled.  */
 	spin_lock(&iommu->lock);
-	arena_free(&iommu->arena, entry, npages);
+	iommu_range_free(iommu, bus_addr, npages);
 	spin_unlock_irqrestore(&iommu->lock, flags);
 
 	return DMA_ERROR_CODE;
@@ -350,9 +313,9 @@ static void dma_4v_unmap_single(struct device *dev, dma_addr_t bus_addr,
 
 	spin_lock_irqsave(&iommu->lock, flags);
 
-	entry = (bus_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT;
-	arena_free(&iommu->arena, entry, npages);
+	iommu_range_free(iommu, bus_addr, npages);
 
+	entry = (bus_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT;
 	do {
 		unsigned long num;
 
@@ -368,88 +331,131 @@ static void dma_4v_unmap_single(struct device *dev, dma_addr_t bus_addr,
 static int dma_4v_map_sg(struct device *dev, struct scatterlist *sglist,
 			 int nelems, enum dma_data_direction direction)
 {
-	unsigned long flags, npages, i, prot;
-	struct scatterlist *sg;
+	struct scatterlist *s, *outs, *segstart;
+	unsigned long flags, handle, prot;
+	dma_addr_t dma_next = 0, dma_addr;
+	unsigned int max_seg_size;
+	int outcount, incount, i;
 	struct iommu *iommu;
-	long entry, err;
-	u32 dma_base;
-
-	/* Fast path single entry scatterlists. */
-	if (nelems == 1) {
-		sglist->dma_address =
-			dma_4v_map_single(dev, sg_virt(sglist),
-					  sglist->length, direction);
-		if (unlikely(sglist->dma_address == DMA_ERROR_CODE))
-			return 0;
-		sglist->dma_length = sglist->length;
-		return 1;
-	}
+	long err;
+
+	BUG_ON(direction == DMA_NONE);
 
 	iommu = dev->archdata.iommu;
+	if (nelems == 0 || !iommu)
+		return 0;
 	
-	if (unlikely(direction == DMA_NONE))
-		goto bad;
-
-	npages = calc_npages(sglist, nelems);
+	prot = HV_PCI_MAP_ATTR_READ;
+	if (direction != DMA_TO_DEVICE)
+		prot |= HV_PCI_MAP_ATTR_WRITE;
 
-	spin_lock_irqsave(&iommu->lock, flags);
-	entry = arena_alloc(&iommu->arena, npages);
-	spin_unlock_irqrestore(&iommu->lock, flags);
+	outs = s = segstart = &sglist[0];
+	outcount = 1;
+	incount = nelems;
+	handle = 0;
 
-	if (unlikely(entry < 0L))
-		goto bad;
+	/* Init first segment length for backout at failure */
+	outs->dma_length = 0;
 
-	dma_base = iommu->page_table_map_base +
-		(entry << IO_PAGE_SHIFT);
+	spin_lock_irqsave(&iommu->lock, flags);
 
-	prot = HV_PCI_MAP_ATTR_READ;
-	if (direction != DMA_TO_DEVICE)
-		prot |= HV_PCI_MAP_ATTR_WRITE;
+	iommu_batch_start(dev, prot, ~0UL);
 
-	local_irq_save(flags);
+	max_seg_size = dma_get_max_seg_size(dev);
+	for_each_sg(sglist, s, nelems, i) {
+		unsigned long paddr, npages, entry, slen;
 
-	iommu_batch_start(dev, prot, entry);
+		slen = s->length;
+		/* Sanity check */
+		if (slen == 0) {
+			dma_next = 0;
+			continue;
+		}
+		/* Allocate iommu entries for that segment */
+		paddr = (unsigned long) SG_ENT_PHYS_ADDRESS(s);
+		npages = iommu_num_pages(paddr, slen);
+		entry = iommu_range_alloc(dev, iommu, npages, &handle);
 
-	for_each_sg(sglist, sg, nelems, i) {
-		unsigned long paddr = SG_ENT_PHYS_ADDRESS(sg);
-		unsigned long slen = sg->length;
-		unsigned long this_npages;
+		/* Handle failure */
+		if (unlikely(entry == DMA_ERROR_CODE)) {
+			if (printk_ratelimit())
+				printk(KERN_INFO "iommu_alloc failed, iommu %p paddr %lx"
+				       " npages %lx\n", iommu, paddr, npages);
+			goto iommu_map_failed;
+		}
 
-		this_npages = iommu_num_pages(paddr, slen);
+		iommu_batch_new_entry(entry);
 
-		sg->dma_address = dma_base | (paddr & ~IO_PAGE_MASK);
-		sg->dma_length = slen;
+		/* Convert entry to a dma_addr_t */
+		dma_addr = iommu->page_table_map_base +
+			(entry << IO_PAGE_SHIFT);
+		dma_addr |= (s->offset & ~IO_PAGE_MASK);
 
+		/* Insert into HW table */
 		paddr &= IO_PAGE_MASK;
-		while (this_npages--) {
+		while (npages--) {
 			err = iommu_batch_add(paddr);
-			if (unlikely(err < 0L)) {
-				local_irq_restore(flags);
+			if (unlikely(err < 0L))
 				goto iommu_map_failed;
+			paddr += IO_PAGE_SIZE;
+		}
+
+		/* If we are in an open segment, try merging */
+		if (segstart != s) {
+			/* We cannot merge if:
+			 * - allocated dma_addr isn't contiguous to previous allocation
+			 */
+			if ((dma_addr != dma_next) ||
+			    (outs->dma_length + s->length > max_seg_size)) {
+				/* Can't merge: create a new segment */
+				segstart = s;
+				outcount++;
+				outs = sg_next(outs);
+			} else {
+				outs->dma_length += s->length;
 			}
+		}
 
-			paddr += IO_PAGE_SIZE;
-			dma_base += IO_PAGE_SIZE;
+		if (segstart == s) {
+			/* This is a new segment, fill entries */
+			outs->dma_address = dma_addr;
+			outs->dma_length = slen;
 		}
+
+		/* Calculate next page pointer for contiguous check */
+		dma_next = dma_addr + slen;
 	}
 
 	err = iommu_batch_end();
 
-	local_irq_restore(flags);
-
 	if (unlikely(err < 0L))
 		goto iommu_map_failed;
 
-	return nelems;
+	spin_unlock_irqrestore(&iommu->lock, flags);
 
-bad:
-	if (printk_ratelimit())
-		WARN_ON(1);
-	return 0;
+	if (outcount < incount) {
+		outs = sg_next(outs);
+		outs->dma_address = DMA_ERROR_CODE;
+		outs->dma_length = 0;
+	}
+
+	return outcount;
 
 iommu_map_failed:
-	spin_lock_irqsave(&iommu->lock, flags);
-	arena_free(&iommu->arena, entry, npages);
+	for_each_sg(sglist, s, nelems, i) {
+		if (s->dma_length != 0) {
+			unsigned long vaddr, npages;
+
+			vaddr = s->dma_address & IO_PAGE_MASK;
+			npages = iommu_num_pages(s->dma_address, s->dma_length);
+			iommu_range_free(iommu, vaddr, npages);
+			/* XXX demap? XXX */
+			s->dma_address = DMA_ERROR_CODE;
+			s->dma_length = 0;
+		}
+		if (s == outs)
+			break;
+	}
 	spin_unlock_irqrestore(&iommu->lock, flags);
 
 	return 0;
@@ -458,39 +464,43 @@ iommu_map_failed:
 static void dma_4v_unmap_sg(struct device *dev, struct scatterlist *sglist,
 			    int nelems, enum dma_data_direction direction)
 {
-	unsigned long flags, npages;
 	struct pci_pbm_info *pbm;
-	u32 devhandle, bus_addr;
+	struct scatterlist *sg;
 	struct iommu *iommu;
-	long entry;
+	unsigned long flags;
+	u32 devhandle;
 
-	if (unlikely(direction == DMA_NONE)) {
-		if (printk_ratelimit())
-			WARN_ON(1);
-	}
+	BUG_ON(direction == DMA_NONE);
 
 	iommu = dev->archdata.iommu;
 	pbm = dev->archdata.host_controller;
 	devhandle = pbm->devhandle;
 	
-	bus_addr = sglist->dma_address & IO_PAGE_MASK;
-
-	npages = calc_npages(sglist, nelems);
-
-	entry = ((bus_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT);
-
 	spin_lock_irqsave(&iommu->lock, flags);
 
-	arena_free(&iommu->arena, entry, npages);
-
-	do {
-		unsigned long num;
+	sg = sglist;
+	while (nelems--) {
+		dma_addr_t dma_handle = sg->dma_address;
+		unsigned int len = sg->dma_length;
+		unsigned long npages, entry;
+
+		if (!len)
+			break;
+		npages = iommu_num_pages(dma_handle, len);
+		iommu_range_free(iommu, dma_handle, npages);
+
+		entry = ((dma_handle - iommu->page_table_map_base) >> IO_PAGE_SHIFT);
+		while (npages) {
+			unsigned long num;
+
+			num = pci_sun4v_iommu_demap(devhandle, HV_PCI_TSBID(0, entry),
+						    npages);
+			entry += num;
+			npages -= num;
+		}
 
-		num = pci_sun4v_iommu_demap(devhandle, HV_PCI_TSBID(0, entry),
-					    npages);
-		entry += num;
-		npages -= num;
-	} while (npages != 0);
+		sg = sg_next(sg);
+	}
 
 	spin_unlock_irqrestore(&iommu->lock, flags);
 }