Merge branch 'akpm' (patches from Andrew Morton)

Merge second patch-bomb from Andrew Morton:
 - a few hotfixes
 - drivers/dma updates
 - MAINTAINERS updates
 - Quite a lot of lib/ updates
 - checkpatch updates
 - binfmt updates
 - autofs4
 - drivers/rtc/
 - various small tweaks to less used filesystems
 - ipc/ updates
 - kernel/watchdog.c changes

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (135 commits)
  mm: softdirty: enable write notifications on VMAs after VM_SOFTDIRTY cleared
  kernel/param: consolidate __{start,stop}___param[] in <linux/moduleparam.h>
  ia64: remove duplicate declarations of __per_cpu_start[] and __per_cpu_end[]
  frv: remove unused declarations of __start___ex_table and __stop___ex_table
  kvm: ensure hard lockup detection is disabled by default
  kernel/watchdog.c: control hard lockup detection default
  staging: rtl8192u: use %*pEn to escape buffer
  staging: rtl8192e: use %*pEn to escape buffer
  staging: wlan-ng: use %*pEhp to print SN
  lib80211: remove unused print_ssid()
  wireless: hostap: proc: print properly escaped SSID
  wireless: ipw2x00: print SSID via %*pE
  wireless: libertas: print esaped string via %*pE
  lib/vsprintf: add %*pE[achnops] format specifier
  lib / string_helpers: introduce string_escape_mem()
  lib / string_helpers: refactoring the test suite
  lib / string_helpers: move documentation to c-file
  include/linux: remove strict_strto* definitions
  arch/x86/mm/numa.c: fix boot failure when all nodes are hotpluggable
  fs: check bh blocknr earlier when searching lru
  ...

5 files changed, 90 insertions, 46 deletions

diff --git a/mm/cma.c b/mm/cma.c
index 474c644a0dc..963bc4add9a 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -58,7 +58,9 @@ unsigned long cma_get_size(struct cma *cma)
 
 static unsigned long cma_bitmap_aligned_mask(struct cma *cma, int align_order)
 {
-	return (1UL << (align_order >> cma->order_per_bit)) - 1;
+	if (align_order <= cma->order_per_bit)
+		return 0;
+	return (1UL << (align_order - cma->order_per_bit)) - 1;
 }
 
 static unsigned long cma_bitmap_maxno(struct cma *cma)
@@ -141,6 +143,54 @@ static int __init cma_init_reserved_areas(void)
 core_initcall(cma_init_reserved_areas);
 
 /**
+ * cma_init_reserved_mem() - create custom contiguous area from reserved memory
+ * @base: Base address of the reserved area
+ * @size: Size of the reserved area (in bytes),
+ * @order_per_bit: Order of pages represented by one bit on bitmap.
+ * @res_cma: Pointer to store the created cma region.
+ *
+ * This function creates custom contiguous area from already reserved memory.
+ */
+int __init cma_init_reserved_mem(phys_addr_t base, phys_addr_t size,
+				 int order_per_bit, struct cma **res_cma)
+{
+	struct cma *cma;
+	phys_addr_t alignment;
+
+	/* Sanity checks */
+	if (cma_area_count == ARRAY_SIZE(cma_areas)) {
+		pr_err("Not enough slots for CMA reserved regions!\n");
+		return -ENOSPC;
+	}
+
+	if (!size || !memblock_is_region_reserved(base, size))
+		return -EINVAL;
+
+	/* ensure minimal alignment requied by mm core */
+	alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order);
+
+	/* alignment should be aligned with order_per_bit */
+	if (!IS_ALIGNED(alignment >> PAGE_SHIFT, 1 << order_per_bit))
+		return -EINVAL;
+
+	if (ALIGN(base, alignment) != base || ALIGN(size, alignment) != size)
+		return -EINVAL;
+
+	/*
+	 * Each reserved area must be initialised later, when more kernel
+	 * subsystems (like slab allocator) are available.
+	 */
+	cma = &cma_areas[cma_area_count];
+	cma->base_pfn = PFN_DOWN(base);
+	cma->count = size >> PAGE_SHIFT;
+	cma->order_per_bit = order_per_bit;
+	*res_cma = cma;
+	cma_area_count++;
+
+	return 0;
+}
+
+/**
  * cma_declare_contiguous() - reserve custom contiguous area
  * @base: Base address of the reserved area optional, use 0 for any
  * @size: Size of the reserved area (in bytes),
@@ -163,7 +213,6 @@ int __init cma_declare_contiguous(phys_addr_t base,
 			phys_addr_t alignment, unsigned int order_per_bit,
 			bool fixed, struct cma **res_cma)
 {
-	struct cma *cma;
 	phys_addr_t memblock_end = memblock_end_of_DRAM();
 	phys_addr_t highmem_start = __pa(high_memory);
 	int ret = 0;
@@ -235,16 +284,9 @@ int __init cma_declare_contiguous(phys_addr_t base,
 		}
 	}
 
-	/*
-	 * Each reserved area must be initialised later, when more kernel
-	 * subsystems (like slab allocator) are available.
-	 */
-	cma = &cma_areas[cma_area_count];
-	cma->base_pfn = PFN_DOWN(base);
-	cma->count = size >> PAGE_SHIFT;
-	cma->order_per_bit = order_per_bit;
-	*res_cma = cma;
-	cma_area_count++;
+	ret = cma_init_reserved_mem(base, size, order_per_bit, res_cma);
+	if (ret)
+		goto err;
 
 	pr_info("Reserved %ld MiB at %08lx\n", (unsigned long)size / SZ_1M,
 		(unsigned long)base);
diff --git a/mm/memory.c b/mm/memory.c
index e229970e422..1cc6bfbd872 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2053,7 +2053,8 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
 	old_page = vm_normal_page(vma, address, orig_pte);
 	if (!old_page) {
 		/*
-		 * VM_MIXEDMAP !pfn_valid() case
+		 * VM_MIXEDMAP !pfn_valid() case, or VM_SOFTDIRTY clear on a
+		 * VM_PFNMAP VMA.
 		 *
 		 * We should not cow pages in a shared writeable mapping.
 		 * Just mark the pages writable as we can't do any dirty
diff --git a/mm/mmap.c b/mm/mmap.c
index 93d28c7e542..7f855206e7f 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -89,6 +89,25 @@ pgprot_t vm_get_page_prot(unsigned long vm_flags)
 }
 EXPORT_SYMBOL(vm_get_page_prot);
 
+static pgprot_t vm_pgprot_modify(pgprot_t oldprot, unsigned long vm_flags)
+{
+	return pgprot_modify(oldprot, vm_get_page_prot(vm_flags));
+}
+
+/* Update vma->vm_page_prot to reflect vma->vm_flags. */
+void vma_set_page_prot(struct vm_area_struct *vma)
+{
+	unsigned long vm_flags = vma->vm_flags;
+
+	vma->vm_page_prot = vm_pgprot_modify(vma->vm_page_prot, vm_flags);
+	if (vma_wants_writenotify(vma)) {
+		vm_flags &= ~VM_SHARED;
+		vma->vm_page_prot = vm_pgprot_modify(vma->vm_page_prot,
+						     vm_flags);
+	}
+}
+
+
 int sysctl_overcommit_memory __read_mostly = OVERCOMMIT_GUESS;  /* heuristic overcommit */
 int sysctl_overcommit_ratio __read_mostly = 50;	/* default is 50% */
 unsigned long sysctl_overcommit_kbytes __read_mostly;
@@ -1475,11 +1494,16 @@ int vma_wants_writenotify(struct vm_area_struct *vma)
 	if (vma->vm_ops && vma->vm_ops->page_mkwrite)
 		return 1;
 
-	/* The open routine did something to the protections already? */
+	/* The open routine did something to the protections that pgprot_modify
+	 * won't preserve? */
 	if (pgprot_val(vma->vm_page_prot) !=
-	    pgprot_val(vm_get_page_prot(vm_flags)))
+	    pgprot_val(vm_pgprot_modify(vma->vm_page_prot, vm_flags)))
 		return 0;
 
+	/* Do we need to track softdirty? */
+	if (IS_ENABLED(CONFIG_MEM_SOFT_DIRTY) && !(vm_flags & VM_SOFTDIRTY))
+		return 1;
+
 	/* Specialty mapping? */
 	if (vm_flags & VM_PFNMAP)
 		return 0;
@@ -1615,21 +1639,6 @@ munmap_back:
 			goto free_vma;
 	}
 
-	if (vma_wants_writenotify(vma)) {
-		pgprot_t pprot = vma->vm_page_prot;
-
-		/* Can vma->vm_page_prot have changed??
-		 *
-		 * Answer: Yes, drivers may have changed it in their
-		 *         f_op->mmap method.
-		 *
-		 * Ensures that vmas marked as uncached stay that way.
-		 */
-		vma->vm_page_prot = vm_get_page_prot(vm_flags & ~VM_SHARED);
-		if (pgprot_val(pprot) == pgprot_val(pgprot_noncached(pprot)))
-			vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
-	}
-
 	vma_link(mm, vma, prev, rb_link, rb_parent);
 	/* Once vma denies write, undo our temporary denial count */
 	if (file) {
@@ -1663,6 +1672,8 @@ out:
 	 */
 	vma->vm_flags |= VM_SOFTDIRTY;
 
+	vma_set_page_prot(vma);
+
 	return addr;
 
 unmap_and_free_vma:
diff --git a/mm/mprotect.c b/mm/mprotect.c
index c43d557941f..ace93454ce8 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -29,13 +29,6 @@
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
 
-#ifndef pgprot_modify
-static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)
-{
-	return newprot;
-}
-#endif
-
 /*
  * For a prot_numa update we only hold mmap_sem for read so there is a
  * potential race with faulting where a pmd was temporarily none. This
@@ -93,7 +86,9 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
 				 * Avoid taking write faults for pages we
 				 * know to be dirty.
 				 */
-				if (dirty_accountable && pte_dirty(ptent))
+				if (dirty_accountable && pte_dirty(ptent) &&
+				    (pte_soft_dirty(ptent) ||
+				     !(vma->vm_flags & VM_SOFTDIRTY)))
 					ptent = pte_mkwrite(ptent);
 				ptep_modify_prot_commit(mm, addr, pte, ptent);
 				updated = true;
@@ -320,13 +315,8 @@ success:
 	 * held in write mode.
 	 */
 	vma->vm_flags = newflags;
-	vma->vm_page_prot = pgprot_modify(vma->vm_page_prot,
-					  vm_get_page_prot(newflags));
-
-	if (vma_wants_writenotify(vma)) {
-		vma->vm_page_prot = vm_get_page_prot(newflags & ~VM_SHARED);
-		dirty_accountable = 1;
-	}
+	dirty_accountable = vma_wants_writenotify(vma);
+	vma_set_page_prot(vma);
 
 	change_protection(vma, start, end, vma->vm_page_prot,
 			  dirty_accountable, 0);
diff --git a/mm/slab.c b/mm/slab.c
index 154aac8411c..eb2b2ea3013 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1992,7 +1992,7 @@ static struct array_cache __percpu *alloc_kmem_cache_cpus(
 	struct array_cache __percpu *cpu_cache;
 
 	size = sizeof(void *) * entries + sizeof(struct array_cache);
-	cpu_cache = __alloc_percpu(size, 0);
+	cpu_cache = __alloc_percpu(size, sizeof(void *));
 
 	if (!cpu_cache)
 		return NULL;