Merge branch 'merge' into next

Merge my own merge branch to get various fixes from there
and upstream, especially the hvc console tty refcouting fixes
which which testing is quite a bit harder...

7 files changed, 60 insertions, 26 deletions

diff --git a/mm/compaction.c b/mm/compaction.c
index 2c4ce17651d8..9eef55838fca 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -346,7 +346,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
          * pages requested were isolated. If there were any failures, 0 is
          * returned and CMA will fail.
          */
-        if (strict && nr_strict_required != total_isolated)
+        if (strict && nr_strict_required > total_isolated)
                 total_isolated = 0;
 
         if (locked)
diff --git a/mm/fremap.c b/mm/fremap.c
index 3899a86851ce..a0aaf0e56800 100644
--- a/mm/fremap.c
+++ b/mm/fremap.c
@@ -169,7 +169,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
         if (vma->vm_private_data && !(vma->vm_flags & VM_NONLINEAR))
                 goto out;
 
-        if (!vma->vm_ops->remap_pages)
+        if (!vma->vm_ops || !vma->vm_ops->remap_pages)
                 goto out;
 
         if (start < vma->vm_start || start + size > vma->vm_end)
diff --git a/mm/memblock.c b/mm/memblock.c
index 931eef145af5..625905523c2a 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -930,6 +930,30 @@ int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t si
         return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
 }
 
+void __init_memblock memblock_trim_memory(phys_addr_t align)
+{
+        int i;
+        phys_addr_t start, end, orig_start, orig_end;
+        struct memblock_type *mem = &memblock.memory;
+
+        for (i = 0; i < mem->cnt; i++) {
+                orig_start = mem->regions[i].base;
+                orig_end = mem->regions[i].base + mem->regions[i].size;
+                start = round_up(orig_start, align);
+                end = round_down(orig_end, align);
+
+                if (start == orig_start && end == orig_end)
+                        continue;
+
+                if (start < end) {
+                        mem->regions[i].base = start;
+                        mem->regions[i].size = end - start;
+                } else {
+                        memblock_remove_region(mem, i);
+                        i--;
+                }
+        }
+}
 
 void __init_memblock memblock_set_current_limit(phys_addr_t limit)
 {
diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c
index 479a1e751a73..8a5ac8c686b0 100644
--- a/mm/mmu_notifier.c
+++ b/mm/mmu_notifier.c
@@ -196,28 +196,28 @@ static int do_mmu_notifier_register(struct mmu_notifier *mn,
         BUG_ON(atomic_read(&mm->mm_users) <= 0);
 
         /*
-        * Verify that mmu_notifier_init() already run and the global srcu is
-        * initialized.
-        */
+         * Verify that mmu_notifier_init() already run and the global srcu is
+         * initialized.
+         */
         BUG_ON(!srcu.per_cpu_ref);
 
+        ret = -ENOMEM;
+        mmu_notifier_mm = kmalloc(sizeof(struct mmu_notifier_mm), GFP_KERNEL);
+        if (unlikely(!mmu_notifier_mm))
+                goto out;
+
         if (take_mmap_sem)
                 down_write(&mm->mmap_sem);
         ret = mm_take_all_locks(mm);
         if (unlikely(ret))
-                goto out;
+                goto out_clean;
 
         if (!mm_has_notifiers(mm)) {
-                mmu_notifier_mm = kmalloc(sizeof(struct mmu_notifier_mm),
-                                        GFP_KERNEL);
-                if (unlikely(!mmu_notifier_mm)) {
-                        ret = -ENOMEM;
-                        goto out_of_mem;
-                }
                 INIT_HLIST_HEAD(&mmu_notifier_mm->list);
                 spin_lock_init(&mmu_notifier_mm->lock);
 
                 mm->mmu_notifier_mm = mmu_notifier_mm;
+                mmu_notifier_mm = NULL;
         }
         atomic_inc(&mm->mm_count);
 
@@ -233,12 +233,12 @@ static int do_mmu_notifier_register(struct mmu_notifier *mn,
         hlist_add_head(&mn->hlist, &mm->mmu_notifier_mm->list);
         spin_unlock(&mm->mmu_notifier_mm->lock);
 
-out_of_mem:
         mm_drop_all_locks(mm);
-out:
+out_clean:
         if (take_mmap_sem)
                 up_write(&mm->mmap_sem);
-
+        kfree(mmu_notifier_mm);
+out:
         BUG_ON(atomic_read(&mm->mm_users) <= 0);
         return ret;
 }
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index bb90971182bd..5b74de6702e0 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1809,10 +1809,10 @@ static void __paginginit init_zone_allows_reclaim(int nid)
         int i;
 
         for_each_online_node(i)
-                if (node_distance(nid, i) <= RECLAIM_DISTANCE) {
+                if (node_distance(nid, i) <= RECLAIM_DISTANCE)
                         node_set(i, NODE_DATA(nid)->reclaim_nodes);
+                else
                         zone_reclaim_mode = 1;
-                }
 }
 
 #else   /* CONFIG_NUMA */
@@ -5825,7 +5825,7 @@ int alloc_contig_range(unsigned long start, unsigned long end,
         ret = start_isolate_page_range(pfn_max_align_down(start),
                                        pfn_max_align_up(end), migratetype);
         if (ret)
-                goto done;
+                return ret;
 
         ret = __alloc_contig_migrate_range(&cc, start, end);
         if (ret)
diff --git a/mm/rmap.c b/mm/rmap.c
index 7df7984d476c..2ee1ef0f317b 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -56,6 +56,7 @@
 #include <linux/mmu_notifier.h>
 #include <linux/migrate.h>
 #include <linux/hugetlb.h>
+#include <linux/backing-dev.h>
 
 #include <asm/tlbflush.h>
 
@@ -926,11 +927,8 @@ int page_mkclean(struct page *page)
 
         if (page_mapped(page)) {
                 struct address_space *mapping = page_mapping(page);
-                if (mapping) {
+                if (mapping)
                         ret = page_mkclean_file(mapping, page);
-                        if (page_test_and_clear_dirty(page_to_pfn(page), 1))
-                                ret = 1;
-                }
         }
 
         return ret;
@@ -1116,6 +1114,7 @@ void page_add_file_rmap(struct page *page)
  */
 void page_remove_rmap(struct page *page)
 {
+        struct address_space *mapping = page_mapping(page);
         bool anon = PageAnon(page);
         bool locked;
         unsigned long flags;
@@ -1138,8 +1137,19 @@ void page_remove_rmap(struct page *page)
          * this if the page is anon, so about to be freed; but perhaps
          * not if it's in swapcache - there might be another pte slot
          * containing the swap entry, but page not yet written to swap.
+         *
+         * And we can skip it on file pages, so long as the filesystem
+         * participates in dirty tracking; but need to catch shm and tmpfs
+         * and ramfs pages which have been modified since creation by read
+         * fault.
+         *
+         * Note that mapping must be decided above, before decrementing
+         * mapcount (which luckily provides a barrier): once page is unmapped,
+         * it could be truncated and page->mapping reset to NULL at any moment.
+         * Note also that we are relying on page_mapping(page) to set mapping
+         * to &swapper_space when PageSwapCache(page).
          */
-        if ((!anon || PageSwapCache(page)) &&
+        if (mapping && !mapping_cap_account_dirty(mapping) &&
             page_test_and_clear_dirty(page_to_pfn(page), 1))
                 set_page_dirty(page);
         /*
diff --git a/mm/slob.c b/mm/slob.c
index a08e4681fd0d..1e921c5e9576 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -429,7 +429,7 @@ static __always_inline void *
 __do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller)
 {
         unsigned int *m;
-        int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
+        int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
         void *ret;
 
         gfp &= gfp_allowed_mask;
@@ -502,7 +502,7 @@ void kfree(const void *block)
 
         sp = virt_to_page(block);
         if (PageSlab(sp)) {
-                int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
+                int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
                 unsigned int *m = (unsigned int *)(block - align);
                 slob_free(m, *m + align);
         } else
@@ -521,7 +521,7 @@ size_t ksize(const void *block)
 
         sp = virt_to_page(block);
         if (PageSlab(sp)) {
-                int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
+                int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
                 unsigned int *m = (unsigned int *)(block - align);
                 return SLOB_UNITS(*m) * SLOB_UNIT;
         } else