sparc64: Revert 16GB huge page support.

It overflows the amount of space available in the initial .text section
of trap handler assembler in some configurations, resulting in build
failures.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

arch/sparc/include/asm/hugetlb.h

@@ -4,13 +4,6 @@
 #include <asm/page.h>
 #include <asm-generic/hugetlb.h>
 
-#ifdef CONFIG_HUGETLB_PAGE
-struct pud_huge_patch_entry {
-	unsigned int addr;
-	unsigned int insn;
-};
-extern struct pud_huge_patch_entry __pud_huge_patch, __pud_huge_patch_end;
-#endif
 
 void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 		     pte_t *ptep, pte_t pte);

arch/sparc/include/asm/page_64.h

@@ -17,7 +17,6 @@
 
 #define HPAGE_SHIFT		23
 #define REAL_HPAGE_SHIFT	22
-#define HPAGE_16GB_SHIFT	34
 #define HPAGE_2GB_SHIFT		31
 #define HPAGE_256MB_SHIFT	28
 #define HPAGE_64K_SHIFT		16
@@ -29,7 +28,7 @@
 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
 #define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
 #define REAL_HPAGE_PER_HPAGE	(_AC(1,UL) << (HPAGE_SHIFT - REAL_HPAGE_SHIFT))
-#define HUGE_MAX_HSTATE		5
+#define HUGE_MAX_HSTATE		4
 #endif
 
 #ifndef __ASSEMBLY__

arch/sparc/include/asm/pgtable_64.h

@@ -414,11 +414,6 @@ static inline bool is_hugetlb_pmd(pmd_t pmd)
 	return !!(pmd_val(pmd) & _PAGE_PMD_HUGE);
 }
 
-static inline bool is_hugetlb_pud(pud_t pud)
-{
-	return !!(pud_val(pud) & _PAGE_PUD_HUGE);
-}
-
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 static inline pmd_t pmd_mkhuge(pmd_t pmd)
 {
@@ -692,8 +687,6 @@ static inline unsigned long pmd_write(pmd_t pmd)
 	return pte_write(pte);
 }
 
-#define pud_write(pud)	pte_write(__pte(pud_val(pud)))
-
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 static inline unsigned long pmd_dirty(pmd_t pmd)
 {
@@ -830,18 +823,9 @@ static inline unsigned long __pmd_page(pmd_t pmd)
 
 	return ((unsigned long) __va(pfn << PAGE_SHIFT));
 }
-
-static inline unsigned long pud_page_vaddr(pud_t pud)
-{
-	pte_t pte = __pte(pud_val(pud));
-	unsigned long pfn;
-
-	pfn = pte_pfn(pte);
-
-	return ((unsigned long) __va(pfn << PAGE_SHIFT));
-}
-
 #define pmd_page(pmd) 			virt_to_page((void *)__pmd_page(pmd))
+#define pud_page_vaddr(pud)		\
+	((unsigned long) __va(pud_val(pud)))
 #define pud_page(pud) 			virt_to_page((void *)pud_page_vaddr(pud))
 #define pmd_clear(pmdp)			(pmd_val(*(pmdp)) = 0UL)
 #define pud_present(pud)		(pud_val(pud) != 0U)

arch/sparc/include/asm/tsb.h

@@ -195,41 +195,6 @@ extern struct tsb_phys_patch_entry __tsb_phys_patch, __tsb_phys_patch_end;
 	 nop; \
 699:
 
-	/* PUD has been loaded into REG1, interpret the value, seeing
-	 * if it is a HUGE PUD or a normal one.  If it is not valid
-	 * then jump to FAIL_LABEL.  If it is a HUGE PUD, and it
-	 * translates to a valid PTE, branch to PTE_LABEL.
-	 *
-	 * We have to propagate bits [32:22] from the virtual address
-	 * to resolve at 4M granularity.
-	 */
-#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
-#define USER_PGTABLE_CHECK_PUD_HUGE(VADDR, REG1, REG2, FAIL_LABEL, PTE_LABEL) \
-700:	ba 700f;					\
-	 nop;						\
-	.section	.pud_huge_patch, "ax";		\
-	.word		700b;				\
-	nop;						\
-	.previous;					\
-	brz,pn		REG1, FAIL_LABEL;		\
-	 sethi		%uhi(_PAGE_PUD_HUGE), REG2;	\
-	sllx		REG2, 32, REG2;			\
-	andcc		REG1, REG2, %g0;		\
-	be,pt		%xcc, 700f;			\
-	 sethi		%hi(0x1ffc0000), REG2;		\
-	sllx		REG2, 1, REG2;			\
-	brgez,pn	REG1, FAIL_LABEL;		\
-	 andn		REG1, REG2, REG1;		\
-	and		VADDR, REG2, REG2;		\
-	brlz,pt		REG1, PTE_LABEL;		\
-	 or		REG1, REG2, REG1;		\
-700:
-#else
-#define USER_PGTABLE_CHECK_PUD_HUGE(VADDR, REG1, REG2, FAIL_LABEL, PTE_LABEL) \
-	brz,pn		REG1, FAIL_LABEL; \
-	 nop;
-#endif
-
 	/* PMD has been loaded into REG1, interpret the value, seeing
 	 * if it is a HUGE PMD or a normal one.  If it is not valid
 	 * then jump to FAIL_LABEL.  If it is a HUGE PMD, and it
@@ -277,7 +242,6 @@ extern struct tsb_phys_patch_entry __tsb_phys_patch, __tsb_phys_patch_end;
 	srlx		REG2, 64 - PAGE_SHIFT, REG2; \
 	andn		REG2, 0x7, REG2; \
 	ldxa		[REG1 + REG2] ASI_PHYS_USE_EC, REG1; \
-	USER_PGTABLE_CHECK_PUD_HUGE(VADDR, REG1, REG2, FAIL_LABEL, 800f) \
 	brz,pn		REG1, FAIL_LABEL; \
 	 sllx		VADDR, 64 - (PMD_SHIFT + PMD_BITS), REG2; \
 	srlx		REG2, 64 - PAGE_SHIFT, REG2; \

arch/sparc/kernel/tsb.S

@@ -117,7 +117,7 @@ tsb_miss_page_table_walk_sun4v_fastpath:
 	/* Valid PTE is now in %g5.  */
 
 #if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
-	sethi		%uhi(_PAGE_PMD_HUGE | _PAGE_PUD_HUGE), %g7
+	sethi		%uhi(_PAGE_PMD_HUGE), %g7
 	sllx		%g7, 32, %g7
 
 	andcc		%g5, %g7, %g0

arch/sparc/kernel/vmlinux.lds.S

@@ -154,11 +154,6 @@ SECTIONS
 		*(.get_tick_patch)
 		__get_tick_patch_end = .;
 	}
-	.pud_huge_patch : {
-		__pud_huge_patch = .;
-		*(.pud_huge_patch)
-		__pud_huge_patch_end = .;
-	}
 	PERCPU_SECTION(SMP_CACHE_BYTES)
 
 #ifdef CONFIG_JUMP_LABEL

arch/sparc/mm/gup.c

@@ -103,45 +103,6 @@ static int gup_huge_pmd(pmd_t *pmdp, pmd_t pmd, unsigned long addr,
 	return 1;
 }
 
-static int gup_huge_pud(pud_t *pudp, pud_t pud, unsigned long addr,
-			unsigned long end, int write, struct page **pages,
-			int *nr)
-{
-	struct page *head, *page;
-	int refs;
-
-	if (!(pud_val(pud) & _PAGE_VALID))
-		return 0;
-
-	if (write && !pud_write(pud))
-		return 0;
-
-	refs = 0;
-	page = pud_page(pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
-	head = compound_head(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(pud_val(pud) != pud_val(*pudp))) {
-		*nr -= refs;
-		while (refs--)
-			put_page(head);
-		return 0;
-	}
-
-	return 1;
-}
-
 static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end,
 		int write, struct page **pages, int *nr)
 {
@@ -180,11 +141,7 @@ static int gup_pud_range(pgd_t pgd, unsigned long addr, unsigned long end,
 		next = pud_addr_end(addr, end);
 		if (pud_none(pud))
 			return 0;
-		if (unlikely(pud_large(pud))) {
-			if (!gup_huge_pud(pudp, pud, addr, next,
-					  write, pages, nr))
-				return 0;
-		} else if (!gup_pmd_range(pud, addr, next, write, pages, nr))
+		if (!gup_pmd_range(pud, addr, next, write, pages, nr))
 			return 0;
 	} while (pudp++, addr = next, addr != end);
 

arch/sparc/mm/hugetlbpage.c

@@ -143,10 +143,6 @@ static pte_t sun4v_hugepage_shift_to_tte(pte_t entry, unsigned int shift)
 	pte_val(entry) = pte_val(entry) & ~_PAGE_SZALL_4V;
 
 	switch (shift) {
-	case HPAGE_16GB_SHIFT:
-		hugepage_size = _PAGE_SZ16GB_4V;
-		pte_val(entry) |= _PAGE_PUD_HUGE;
-		break;
 	case HPAGE_2GB_SHIFT:
 		hugepage_size = _PAGE_SZ2GB_4V;
 		pte_val(entry) |= _PAGE_PMD_HUGE;
@@ -191,9 +187,6 @@ static unsigned int sun4v_huge_tte_to_shift(pte_t entry)
 	unsigned int shift;
 
 	switch (tte_szbits) {
-	case _PAGE_SZ16GB_4V:
-		shift = HPAGE_16GB_SHIFT;
-		break;
 	case _PAGE_SZ2GB_4V:
 		shift = HPAGE_2GB_SHIFT;
 		break;
@@ -266,19 +259,22 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
 	pgd_t *pgd;
 	pud_t *pud;
 	pmd_t *pmd;
+	pte_t *pte = NULL;
 
 	pgd = pgd_offset(mm, addr);
 	pud = pud_alloc(mm, pgd, addr);
-	if (!pud)
-		return NULL;
-	if (sz >= PUD_SIZE)
-		return (pte_t *)pud;
-	pmd = pmd_alloc(mm, pud, addr);
-	if (!pmd)
-		return NULL;
-	if (sz >= PMD_SIZE)
-		return (pte_t *)pmd;
-	return pte_alloc_map(mm, pmd, addr);
+	if (pud) {
+		pmd = pmd_alloc(mm, pud, addr);
+		if (!pmd)
+			return NULL;
+
+		if (sz >= PMD_SIZE)
+			pte = (pte_t *)pmd;
+		else
+			pte = pte_alloc_map(mm, pmd, addr);
+	}
+
+	return pte;
 }
 
 pte_t *huge_pte_offset(struct mm_struct *mm,
@@ -287,40 +283,34 @@ pte_t *huge_pte_offset(struct mm_struct *mm,
 	pgd_t *pgd;
 	pud_t *pud;
 	pmd_t *pmd;
+	pte_t *pte = NULL;
 
 	pgd = pgd_offset(mm, addr);
-	if (pgd_none(*pgd))
-		return NULL;
-	pud = pud_offset(pgd, addr);
-	if (pud_none(*pud))
-		return NULL;
-	if (is_hugetlb_pud(*pud))
-		return (pte_t *)pud;
-	pmd = pmd_offset(pud, addr);
-	if (pmd_none(*pmd))
-		return NULL;
-	if (is_hugetlb_pmd(*pmd))
-		return (pte_t *)pmd;
-	return pte_offset_map(pmd, addr);
+	if (!pgd_none(*pgd)) {
+		pud = pud_offset(pgd, addr);
+		if (!pud_none(*pud)) {
+			pmd = pmd_offset(pud, addr);
+			if (!pmd_none(*pmd)) {
+				if (is_hugetlb_pmd(*pmd))
+					pte = (pte_t *)pmd;
+				else
+					pte = pte_offset_map(pmd, addr);
+			}
+		}
+	}
+
+	return pte;
 }
 
 void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 		     pte_t *ptep, pte_t entry)
 {
-	unsigned int nptes, orig_shift, shift;
-	unsigned long i, size;
+	unsigned int i, nptes, orig_shift, shift;
+	unsigned long size;
 	pte_t orig;
 
 	size = huge_tte_to_size(entry);
-
-	shift = PAGE_SHIFT;
-	if (size >= PUD_SIZE)
-		shift = PUD_SHIFT;
-	else if (size >= PMD_SIZE)
-		shift = PMD_SHIFT;
-	else
-		shift = PAGE_SHIFT;
-
+	shift = size >= HPAGE_SIZE ? PMD_SHIFT : PAGE_SHIFT;
 	nptes = size >> shift;
 
 	if (!pte_present(*ptep) && pte_present(entry))
@@ -343,23 +333,19 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 			      pte_t *ptep)
 {
-	unsigned int i, nptes, orig_shift, shift;
+	unsigned int i, nptes, hugepage_shift;
 	unsigned long size;
 	pte_t entry;
 
 	entry = *ptep;
 	size = huge_tte_to_size(entry);
-
-	shift = PAGE_SHIFT;
-	if (size >= PUD_SIZE)
-		shift = PUD_SHIFT;
-	else if (size >= PMD_SIZE)
-		shift = PMD_SHIFT;
+	if (size >= HPAGE_SIZE)
+		nptes = size >> PMD_SHIFT;
 	else
-		shift = PAGE_SHIFT;
+		nptes = size >> PAGE_SHIFT;
 
-	nptes = size >> shift;
-	orig_shift = pte_none(entry) ? PAGE_SHIFT : huge_tte_to_shift(entry);
+	hugepage_shift = pte_none(entry) ? PAGE_SHIFT :
+		huge_tte_to_shift(entry);
 
 	if (pte_present(entry))
 		mm->context.hugetlb_pte_count -= nptes;
@@ -368,11 +354,11 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 	for (i = 0; i < nptes; i++)
 		ptep[i] = __pte(0UL);
 
-	maybe_tlb_batch_add(mm, addr, ptep, entry, 0, orig_shift);
+	maybe_tlb_batch_add(mm, addr, ptep, entry, 0, hugepage_shift);
 	/* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */
 	if (size == HPAGE_SIZE)
 		maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, entry, 0,
-				    orig_shift);
+				    hugepage_shift);
 
 	return entry;
 }
@@ -385,8 +371,7 @@ int pmd_huge(pmd_t pmd)
 
 int pud_huge(pud_t pud)
 {
-	return !pud_none(pud) &&
-		(pud_val(pud) & (_PAGE_VALID|_PAGE_PUD_HUGE)) != _PAGE_VALID;
+	return 0;
 }
 
 static void hugetlb_free_pte_range(struct mmu_gather *tlb, pmd_t *pmd,
@@ -450,11 +435,8 @@ static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
 		next = pud_addr_end(addr, end);
 		if (pud_none_or_clear_bad(pud))
 			continue;
-		if (is_hugetlb_pud(*pud))
-			pud_clear(pud);
-		else
-			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
-					       ceiling);
+		hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
+				       ceiling);
 	} while (pud++, addr = next, addr != end);
 
 	start &= PGDIR_MASK;

arch/sparc/mm/init_64.c

@@ -325,18 +325,6 @@ static void __update_mmu_tsb_insert(struct mm_struct *mm, unsigned long tsb_inde
 }
 
 #ifdef CONFIG_HUGETLB_PAGE
-static void __init pud_huge_patch(void)
-{
-	struct pud_huge_patch_entry *p;
-	unsigned long addr;
-
-	p = &__pud_huge_patch;
-	addr = p->addr;
-	*(unsigned int *)addr = p->insn;
-
-	__asm__ __volatile__("flush %0" : : "r" (addr));
-}
-
 static int __init setup_hugepagesz(char *string)
 {
 	unsigned long long hugepage_size;
@@ -349,11 +337,6 @@ static int __init setup_hugepagesz(char *string)
 	hugepage_shift = ilog2(hugepage_size);
 
 	switch (hugepage_shift) {
-	case HPAGE_16GB_SHIFT:
-		hv_pgsz_mask = HV_PGSZ_MASK_16GB;
-		hv_pgsz_idx = HV_PGSZ_IDX_16GB;
-		pud_huge_patch();
-		break;
 	case HPAGE_2GB_SHIFT:
 		hv_pgsz_mask = HV_PGSZ_MASK_2GB;
 		hv_pgsz_idx = HV_PGSZ_IDX_2GB;
@@ -394,7 +377,6 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *
 {
 	struct mm_struct *mm;
 	unsigned long flags;
-	bool is_huge_tsb;
 	pte_t pte = *ptep;
 
 	if (tlb_type != hypervisor) {
@@ -412,37 +394,15 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *
 
 	spin_lock_irqsave(&mm->context.lock, flags);
 
-	is_huge_tsb = false;
 #if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
-	if (mm->context.hugetlb_pte_count || mm->context.thp_pte_count) {
-		unsigned long hugepage_size = PAGE_SIZE;
-
-		if (is_vm_hugetlb_page(vma))
-			hugepage_size = huge_page_size(hstate_vma(vma));
-
-		if (hugepage_size >= PUD_SIZE) {
-			unsigned long mask = 0x1ffc00000UL;
-
-			/* Transfer bits [32:22] from address to resolve
-			 * at 4M granularity.
-			 */
-			pte_val(pte) &= ~mask;
-			pte_val(pte) |= (address & mask);
-		} else if (hugepage_size >= PMD_SIZE) {
-			/* We are fabricating 8MB pages using 4MB
-			 * real hw pages.
-			 */
-			pte_val(pte) |= (address & (1UL << REAL_HPAGE_SHIFT));
-		}
-
-		if (hugepage_size >= PMD_SIZE) {
-			__update_mmu_tsb_insert(mm, MM_TSB_HUGE,
-				REAL_HPAGE_SHIFT, address, pte_val(pte));
-			is_huge_tsb = true;
-		}
-	}
+	if ((mm->context.hugetlb_pte_count || mm->context.thp_pte_count) &&
+	    is_hugetlb_pmd(__pmd(pte_val(pte)))) {
+		/* We are fabricating 8MB pages using 4MB real hw pages.  */
+		pte_val(pte) |= (address & (1UL << REAL_HPAGE_SHIFT));
+		__update_mmu_tsb_insert(mm, MM_TSB_HUGE, REAL_HPAGE_SHIFT,
+					address, pte_val(pte));
+	} else
 #endif
-	if (!is_huge_tsb)
 		__update_mmu_tsb_insert(mm, MM_TSB_BASE, PAGE_SHIFT,
 					address, pte_val(pte));