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

Pull sparc fixes from David Miller:
 "A couple small fixes for sparc including some THP brown-paper-bag
  material:

   1) During the merging of all the THP support for various
      architectures, sparc missed adding a
      HAVE_ARCH_TRANSPARENT_HUGEPAGE to it's Kconfig, oops.

   2) Sparc needs to be mindful of hugepages in get_user_pages_fast().

   3) Fix memory leak in SBUS probe, from Cong Ding.

   4) The sunvdc virtual disk client driver has a test of the bitmask of
      vdisk server supported operations which was off by one bit"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sunvdc: Fix off-by-one in generic_request().
  sparc64: Fix get_user_pages_fast() wrt. THP.
  sparc64: Add missing HAVE_ARCH_TRANSPARENT_HUGEPAGE.
  sparc: kernel/sbus.c: fix memory leakage

4 files changed, 67 insertions, 13 deletions

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 9f2edb5c5551..cb9c333d74e8 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -61,6 +61,7 @@ config SPARC64
 	select HAVE_MEMBLOCK
 	select HAVE_MEMBLOCK_NODE_MAP
 	select HAVE_SYSCALL_WRAPPERS
+	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
 	select HAVE_DYNAMIC_FTRACE
 	select HAVE_FTRACE_MCOUNT_RECORD
 	select HAVE_SYSCALL_TRACEPOINTS
diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h
index 7870be0f5adc..08fcce90316b 100644
--- a/arch/sparc/include/asm/pgtable_64.h
+++ b/arch/sparc/include/asm/pgtable_64.h
@@ -71,7 +71,6 @@
 #define PMD_PADDR	_AC(0xfffffffe,UL)
 #define PMD_PADDR_SHIFT	_AC(11,UL)
 
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
 #define PMD_ISHUGE	_AC(0x00000001,UL)
 
 /* This is the PMD layout when PMD_ISHUGE is set.  With 4MB huge
@@ -86,7 +85,6 @@
 #define PMD_HUGE_ACCESSED	_AC(0x00000080,UL)
 #define PMD_HUGE_EXEC		_AC(0x00000040,UL)
 #define PMD_HUGE_SPLITTING	_AC(0x00000020,UL)
-#endif
 
 /* PGDs point to PMD tables which are 8K aligned.  */
 #define PGD_PADDR	_AC(0xfffffffc,UL)
@@ -628,6 +626,12 @@ static inline unsigned long pte_special(pte_t pte)
 	return pte_val(pte) & _PAGE_SPECIAL;
 }
 
+static inline int pmd_large(pmd_t pmd)
+{
+	return (pmd_val(pmd) & (PMD_ISHUGE | PMD_HUGE_PRESENT)) ==
+		(PMD_ISHUGE | PMD_HUGE_PRESENT);
+}
+
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 static inline int pmd_young(pmd_t pmd)
 {
@@ -646,12 +650,6 @@ static inline unsigned long pmd_pfn(pmd_t pmd)
 	return val >> (PAGE_SHIFT - PMD_PADDR_SHIFT);
 }
 
-static inline int pmd_large(pmd_t pmd)
-{
-	return (pmd_val(pmd) & (PMD_ISHUGE | PMD_HUGE_PRESENT)) ==
-		(PMD_ISHUGE | PMD_HUGE_PRESENT);
-}
-
 static inline int pmd_trans_splitting(pmd_t pmd)
 {
 	return (pmd_val(pmd) & (PMD_ISHUGE|PMD_HUGE_SPLITTING)) ==
diff --git a/arch/sparc/kernel/sbus.c b/arch/sparc/kernel/sbus.c
index 1271b3a27d4e..be5bdf93c767 100644
--- a/arch/sparc/kernel/sbus.c
+++ b/arch/sparc/kernel/sbus.c
@@ -554,10 +554,8 @@ static void __init sbus_iommu_init(struct platform_device *op)
 	regs = pr->phys_addr;
 
 	iommu = kzalloc(sizeof(*iommu), GFP_ATOMIC);
-	if (!iommu)
-		goto fatal_memory_error;
 	strbuf = kzalloc(sizeof(*strbuf), GFP_ATOMIC);
-	if (!strbuf)
+	if (!iommu || !strbuf)
 		goto fatal_memory_error;
 
 	op->dev.archdata.iommu = iommu;
@@ -656,6 +654,8 @@ static void __init sbus_iommu_init(struct platform_device *op)
 	return;
 
 fatal_memory_error:
+	kfree(iommu);
+	kfree(strbuf);
 	prom_printf("sbus_iommu_init: Fatal memory allocation error.\n");
 }
 
diff --git a/arch/sparc/mm/gup.c b/arch/sparc/mm/gup.c
index 42c55df3aec3..01ee23dd724d 100644
--- a/arch/sparc/mm/gup.c
+++ b/arch/sparc/mm/gup.c
@@ -66,6 +66,56 @@ static noinline int gup_pte_range(pmd_t pmd, unsigned long addr,
 	return 1;
 }
 
+static int gup_huge_pmd(pmd_t *pmdp, pmd_t pmd, unsigned long addr,
+			unsigned long end, int write, struct page **pages,
+			int *nr)
+{
+	struct page *head, *page, *tail;
+	u32 mask;
+	int refs;
+
+	mask = PMD_HUGE_PRESENT;
+	if (write)
+		mask |= PMD_HUGE_WRITE;
+	if ((pmd_val(pmd) & mask) != mask)
+		return 0;
+
+	refs = 0;
+	head = pmd_page(pmd);
+	page = head + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
+	tail = page;
+	do {
+		VM_BUG_ON(compound_head(page) != head);
+		pages[*nr] = page;
+		(*nr)++;
+		page++;
+		refs++;
+	} while (addr += PAGE_SIZE, addr != end);
+
+	if (!page_cache_add_speculative(head, refs)) {
+		*nr -= refs;
+		return 0;
+	}
+
+	if (unlikely(pmd_val(pmd) != pmd_val(*pmdp))) {
+		*nr -= refs;
+		while (refs--)
+			put_page(head);
+		return 0;
+	}
+
+	/* Any tail page need their mapcount reference taken before we
+	 * return.
+	 */
+	while (refs--) {
+		if (PageTail(tail))
+			get_huge_page_tail(tail);
+		tail++;
+	}
+
+	return 1;
+}
+
 static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end,
 		int write, struct page **pages, int *nr)
 {
@@ -77,9 +127,14 @@ static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end,
 		pmd_t pmd = *pmdp;
 
 		next = pmd_addr_end(addr, end);
-		if (pmd_none(pmd))
+		if (pmd_none(pmd) || pmd_trans_splitting(pmd))
 			return 0;
-		if (!gup_pte_range(pmd, addr, next, write, pages, nr))
+		if (unlikely(pmd_large(pmd))) {
+			if (!gup_huge_pmd(pmdp, pmd, addr, next,
+					  write, pages, nr))
+				return 0;
+		} else if (!gup_pte_range(pmd, addr, next, write,
+					  pages, nr))
 			return 0;
 	} while (pmdp++, addr = next, addr != end);