Merge 'akpm' patch series

* Merge akpm patch series: (122 commits)
  drivers/connector/cn_proc.c: remove unused local
  Documentation/SubmitChecklist: add RCU debug config options
  reiserfs: use hweight_long()
  reiserfs: use proper little-endian bitops
  pnpacpi: register disabled resources
  drivers/rtc/rtc-tegra.c: properly initialize spinlock
  drivers/rtc/rtc-twl.c: check return value of twl_rtc_write_u8() in twl_rtc_set_time()
  drivers/rtc: add support for Qualcomm PMIC8xxx RTC
  drivers/rtc/rtc-s3c.c: support clock gating
  drivers/rtc/rtc-mpc5121.c: add support for RTC on MPC5200
  init: skip calibration delay if previously done
  misc/eeprom: add eeprom access driver for digsy_mtc board
  misc/eeprom: add driver for microwire 93xx46 EEPROMs
  checkpatch.pl: update $logFunctions
  checkpatch: make utf-8 test --strict
  checkpatch.pl: add ability to ignore various messages
  checkpatch: add a "prefer __aligned" check
  checkpatch: validate signature styles and To: and Cc: lines
  checkpatch: add __rcu as a sparse modifier
  checkpatch: suggest using min_t or max_t
  ...

Did this as a merge because of (trivial) conflicts in
 - Documentation/feature-removal-schedule.txt
 - arch/xtensa/include/asm/uaccess.h
that were just easier to fix up in the merge than in the patch series.

arch/sparc/Kconfig

@@ -41,6 +41,7 @@ config SPARC64
 	select HAVE_FUNCTION_TRACE_MCOUNT_TEST
 	select HAVE_KRETPROBES
 	select HAVE_KPROBES
+	select HAVE_RCU_TABLE_FREE if SMP
 	select HAVE_MEMBLOCK
 	select HAVE_SYSCALL_WRAPPERS
 	select HAVE_DYNAMIC_FTRACE
@@ -81,10 +82,6 @@ config IOMMU_HELPER
 	bool
 	default y if SPARC64
 
-config QUICKLIST
-	bool
-	default y if SPARC64
-
 config STACKTRACE_SUPPORT
 	bool
 	default y if SPARC64

arch/sparc/include/asm/pgalloc_64.h

@@ -5,7 +5,6 @@
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
-#include <linux/quicklist.h>
 
 #include <asm/spitfire.h>
 #include <asm/cpudata.h>
@@ -14,71 +13,114 @@
 
 /* Page table allocation/freeing. */
 
+extern struct kmem_cache *pgtable_cache;
+
 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 {
-	return quicklist_alloc(0, GFP_KERNEL, NULL);
+	return kmem_cache_alloc(pgtable_cache, GFP_KERNEL);
 }
 
 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 {
-	quicklist_free(0, NULL, pgd);
+	kmem_cache_free(pgtable_cache, pgd);
 }
 
 #define pud_populate(MM, PUD, PMD)	pud_set(PUD, PMD)
 
 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
-	return quicklist_alloc(0, GFP_KERNEL, NULL);
+	return kmem_cache_alloc(pgtable_cache,
+				GFP_KERNEL|__GFP_REPEAT);
 }
 
 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
 {
-	quicklist_free(0, NULL, pmd);
+	kmem_cache_free(pgtable_cache, pmd);
 }
 
 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 					  unsigned long address)
 {
-	return quicklist_alloc(0, GFP_KERNEL, NULL);
+	return (pte_t *)__get_free_page(GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO);
 }
 
 static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
 					unsigned long address)
 {
 	struct page *page;
-	void *pg;
+	pte_t *pte;
 
-	pg = quicklist_alloc(0, GFP_KERNEL, NULL);
-	if (!pg)
+	pte = pte_alloc_one_kernel(mm, address);
+	if (!pte)
 		return NULL;
-	page = virt_to_page(pg);
+	page = virt_to_page(pte);
 	pgtable_page_ctor(page);
 	return page;
 }
 
 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
 {
-	quicklist_free(0, NULL, pte);
+	free_page((unsigned long)pte);
 }
 
 static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
 {
 	pgtable_page_dtor(ptepage);
-	quicklist_free_page(0, NULL, ptepage);
+	__free_page(ptepage);
 }
 
-
 #define pmd_populate_kernel(MM, PMD, PTE)	pmd_set(PMD, PTE)
 #define pmd_populate(MM,PMD,PTE_PAGE)		\
 	pmd_populate_kernel(MM,PMD,page_address(PTE_PAGE))
 #define pmd_pgtable(pmd) pmd_page(pmd)
 
-static inline void check_pgt_cache(void)
+#define check_pgt_cache()	do { } while (0)
+
+static inline void pgtable_free(void *table, bool is_page)
 {
-	quicklist_trim(0, NULL, 25, 16);
+	if (is_page)
+		free_page((unsigned long)table);
+	else
+		kmem_cache_free(pgtable_cache, table);
 }
 
-#define __pte_free_tlb(tlb, pte, addr)	pte_free((tlb)->mm, pte)
-#define __pmd_free_tlb(tlb, pmd, addr)	pmd_free((tlb)->mm, pmd)
+#ifdef CONFIG_SMP
+
+struct mmu_gather;
+extern void tlb_remove_table(struct mmu_gather *, void *);
+
+static inline void pgtable_free_tlb(struct mmu_gather *tlb, void *table, bool is_page)
+{
+	unsigned long pgf = (unsigned long)table;
+	if (is_page)
+		pgf |= 0x1UL;
+	tlb_remove_table(tlb, (void *)pgf);
+}
+
+static inline void __tlb_remove_table(void *_table)
+{
+	void *table = (void *)((unsigned long)_table & ~0x1UL);
+	bool is_page = false;
+
+	if ((unsigned long)_table & 0x1UL)
+		is_page = true;
+	pgtable_free(table, is_page);
+}
+#else /* CONFIG_SMP */
+static inline void pgtable_free_tlb(struct mmu_gather *tlb, void *table, bool is_page)
+{
+	pgtable_free(table, is_page);
+}
+#endif /* !CONFIG_SMP */
+
+static inline void __pte_free_tlb(struct mmu_gather *tlb, struct page *ptepage,
+				  unsigned long address)
+{
+	pgtable_page_dtor(ptepage);
+	pgtable_free_tlb(tlb, page_address(ptepage), true);
+}
+
+#define __pmd_free_tlb(tlb, pmd, addr)		      \
+	pgtable_free_tlb(tlb, pmd, false)
 
 #endif /* _SPARC64_PGALLOC_H */

arch/sparc/include/asm/pgtable_64.h

@@ -95,6 +95,10 @@
 /* PTE bits which are the same in SUN4U and SUN4V format.  */
 #define _PAGE_VALID	  _AC(0x8000000000000000,UL) /* Valid TTE            */
 #define _PAGE_R	  	  _AC(0x8000000000000000,UL) /* Keep ref bit uptodate*/
+#define _PAGE_SPECIAL     _AC(0x0200000000000000,UL) /* Special page         */
+
+/* Advertise support for _PAGE_SPECIAL */
+#define __HAVE_ARCH_PTE_SPECIAL
 
 /* SUN4U pte bits... */
 #define _PAGE_SZ4MB_4U	  _AC(0x6000000000000000,UL) /* 4MB Page             */
@@ -104,6 +108,7 @@
 #define _PAGE_NFO_4U	  _AC(0x1000000000000000,UL) /* No Fault Only        */
 #define _PAGE_IE_4U	  _AC(0x0800000000000000,UL) /* Invert Endianness    */
 #define _PAGE_SOFT2_4U	  _AC(0x07FC000000000000,UL) /* Software bits, set 2 */
+#define _PAGE_SPECIAL_4U  _AC(0x0200000000000000,UL) /* Special page         */
 #define _PAGE_RES1_4U	  _AC(0x0002000000000000,UL) /* Reserved             */
 #define _PAGE_SZ32MB_4U	  _AC(0x0001000000000000,UL) /* (Panther) 32MB page  */
 #define _PAGE_SZ256MB_4U  _AC(0x2001000000000000,UL) /* (Panther) 256MB page */
@@ -133,6 +138,7 @@
 #define _PAGE_ACCESSED_4V _AC(0x1000000000000000,UL) /* Accessed (ref'd)     */
 #define _PAGE_READ_4V	  _AC(0x0800000000000000,UL) /* Readable SW Bit      */
 #define _PAGE_WRITE_4V	  _AC(0x0400000000000000,UL) /* Writable SW Bit      */
+#define _PAGE_SPECIAL_4V  _AC(0x0200000000000000,UL) /* Special page         */
 #define _PAGE_PADDR_4V	  _AC(0x00FFFFFFFFFFE000,UL) /* paddr[55:13]         */
 #define _PAGE_IE_4V	  _AC(0x0000000000001000,UL) /* Invert Endianness    */
 #define _PAGE_E_4V	  _AC(0x0000000000000800,UL) /* side-Effect          */
@@ -302,10 +308,10 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t prot)
 	: "=r" (mask), "=r" (tmp)
 	: "i" (_PAGE_PADDR_4U | _PAGE_MODIFIED_4U | _PAGE_ACCESSED_4U |
 	       _PAGE_CP_4U | _PAGE_CV_4U | _PAGE_E_4U | _PAGE_PRESENT_4U |
-	       _PAGE_SZBITS_4U),
+	       _PAGE_SZBITS_4U | _PAGE_SPECIAL),
 	  "i" (_PAGE_PADDR_4V | _PAGE_MODIFIED_4V | _PAGE_ACCESSED_4V |
 	       _PAGE_CP_4V | _PAGE_CV_4V | _PAGE_E_4V | _PAGE_PRESENT_4V |
-	       _PAGE_SZBITS_4V));
+	       _PAGE_SZBITS_4V | _PAGE_SPECIAL));
 
 	return __pte((pte_val(pte) & mask) | (pgprot_val(prot) & ~mask));
 }
@@ -502,6 +508,7 @@ static inline pte_t pte_mkyoung(pte_t pte)
 
 static inline pte_t pte_mkspecial(pte_t pte)
 {
+	pte_val(pte) |= _PAGE_SPECIAL;
 	return pte;
 }
 
@@ -607,9 +614,9 @@ static inline unsigned long pte_present(pte_t pte)
 	return val;
 }
 
-static inline int pte_special(pte_t pte)
+static inline unsigned long pte_special(pte_t pte)
 {
-	return 0;
+	return pte_val(pte) & _PAGE_SPECIAL;
 }
 
 #define pmd_set(pmdp, ptep)	\

arch/sparc/mm/Makefile

@@ -4,7 +4,7 @@
 asflags-y := -ansi
 ccflags-y := -Werror
 
-obj-$(CONFIG_SPARC64)   += ultra.o tlb.o tsb.o
+obj-$(CONFIG_SPARC64)   += ultra.o tlb.o tsb.o gup.o
 obj-y                   += fault_$(BITS).o
 obj-y                   += init_$(BITS).o
 obj-$(CONFIG_SPARC32)   += loadmmu.o

arch/sparc/mm/gup.c

@@ -0,0 +1,181 @@
+/*
+ * Lockless get_user_pages_fast for sparc, cribbed from powerpc
+ *
+ * Copyright (C) 2008 Nick Piggin
+ * Copyright (C) 2008 Novell Inc.
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/vmstat.h>
+#include <linux/pagemap.h>
+#include <linux/rwsem.h>
+#include <asm/pgtable.h>
+
+/*
+ * The performance critical leaf functions are made noinline otherwise gcc
+ * inlines everything into a single function which results in too much
+ * register pressure.
+ */
+static noinline int gup_pte_range(pmd_t pmd, unsigned long addr,
+		unsigned long end, int write, struct page **pages, int *nr)
+{
+	unsigned long mask, result;
+	pte_t *ptep;
+
+	if (tlb_type == hypervisor) {
+		result = _PAGE_PRESENT_4V|_PAGE_P_4V;
+		if (write)
+			result |= _PAGE_WRITE_4V;
+	} else {
+		result = _PAGE_PRESENT_4U|_PAGE_P_4U;
+		if (write)
+			result |= _PAGE_WRITE_4U;
+	}
+	mask = result | _PAGE_SPECIAL;
+
+	ptep = pte_offset_kernel(&pmd, addr);
+	do {
+		struct page *page, *head;
+		pte_t pte = *ptep;
+
+		if ((pte_val(pte) & mask) != result)
+			return 0;
+		VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
+
+		/* The hugepage case is simplified on sparc64 because
+		 * we encode the sub-page pfn offsets into the
+		 * hugepage PTEs.  We could optimize this in the future
+		 * use page_cache_add_speculative() for the hugepage case.
+		 */
+		page = pte_page(pte);
+		head = compound_head(page);
+		if (!page_cache_get_speculative(head))
+			return 0;
+		if (unlikely(pte_val(pte) != pte_val(*ptep))) {
+			put_page(head);
+			return 0;
+		}
+
+		pages[*nr] = page;
+		(*nr)++;
+	} while (ptep++, addr += PAGE_SIZE, addr != end);
+
+	return 1;
+}
+
+static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end,
+		int write, struct page **pages, int *nr)
+{
+	unsigned long next;
+	pmd_t *pmdp;
+
+	pmdp = pmd_offset(&pud, addr);
+	do {
+		pmd_t pmd = *pmdp;
+
+		next = pmd_addr_end(addr, end);
+		if (pmd_none(pmd))
+			return 0;
+		if (!gup_pte_range(pmd, addr, next, write, pages, nr))
+			return 0;
+	} while (pmdp++, addr = next, addr != end);
+
+	return 1;
+}
+
+static int gup_pud_range(pgd_t pgd, unsigned long addr, unsigned long end,
+		int write, struct page **pages, int *nr)
+{
+	unsigned long next;
+	pud_t *pudp;
+
+	pudp = pud_offset(&pgd, addr);
+	do {
+		pud_t pud = *pudp;
+
+		next = pud_addr_end(addr, end);
+		if (pud_none(pud))
+			return 0;
+		if (!gup_pmd_range(pud, addr, next, write, pages, nr))
+			return 0;
+	} while (pudp++, addr = next, addr != end);
+
+	return 1;
+}
+
+int get_user_pages_fast(unsigned long start, int nr_pages, int write,
+			struct page **pages)
+{
+	struct mm_struct *mm = current->mm;
+	unsigned long addr, len, end;
+	unsigned long next;
+	pgd_t *pgdp;
+	int nr = 0;
+
+	start &= PAGE_MASK;
+	addr = start;
+	len = (unsigned long) nr_pages << PAGE_SHIFT;
+	end = start + len;
+
+	/*
+	 * XXX: batch / limit 'nr', to avoid large irq off latency
+	 * needs some instrumenting to determine the common sizes used by
+	 * important workloads (eg. DB2), and whether limiting the batch size
+	 * will decrease performance.
+	 *
+	 * It seems like we're in the clear for the moment. Direct-IO is
+	 * the main guy that batches up lots of get_user_pages, and even
+	 * they are limited to 64-at-a-time which is not so many.
+	 */
+	/*
+	 * This doesn't prevent pagetable teardown, but does prevent
+	 * the pagetables from being freed on sparc.
+	 *
+	 * So long as we atomically load page table pointers versus teardown,
+	 * we can follow the address down to the the page and take a ref on it.
+	 */
+	local_irq_disable();
+
+	pgdp = pgd_offset(mm, addr);
+	do {
+		pgd_t pgd = *pgdp;
+
+		next = pgd_addr_end(addr, end);
+		if (pgd_none(pgd))
+			goto slow;
+		if (!gup_pud_range(pgd, addr, next, write, pages, &nr))
+			goto slow;
+	} while (pgdp++, addr = next, addr != end);
+
+	local_irq_enable();
+
+	VM_BUG_ON(nr != (end - start) >> PAGE_SHIFT);
+	return nr;
+
+	{
+		int ret;
+
+slow:
+		local_irq_enable();
+
+		/* Try to get the remaining pages with get_user_pages */
+		start += nr << PAGE_SHIFT;
+		pages += nr;
+
+		down_read(&mm->mmap_sem);
+		ret = get_user_pages(current, mm, start,
+			(end - start) >> PAGE_SHIFT, write, 0, pages, NULL);
+		up_read(&mm->mmap_sem);
+
+		/* Have to be a bit careful with return values */
+		if (nr > 0) {
+			if (ret < 0)
+				ret = nr;
+			else
+				ret += nr;
+		}
+
+		return ret;
+	}
+}

arch/sparc/mm/tsb.c

@@ -236,6 +236,8 @@ static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_idx, unsign
 	}
 }
 
+struct kmem_cache *pgtable_cache __read_mostly;
+
 static struct kmem_cache *tsb_caches[8] __read_mostly;
 
 static const char *tsb_cache_names[8] = {
@@ -253,6 +255,15 @@ void __init pgtable_cache_init(void)
 {
 	unsigned long i;
 
+	pgtable_cache = kmem_cache_create("pgtable_cache",
+					  PAGE_SIZE, PAGE_SIZE,
+					  0,
+					  _clear_page);
+	if (!pgtable_cache) {
+		prom_printf("pgtable_cache_init(): Could not create!\n");
+		prom_halt();
+	}
+
 	for (i = 0; i < 8; i++) {
 		unsigned long size = 8192 << i;
 		const char *name = tsb_cache_names[i];