Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdim...

[mirror_ubuntu-artful-kernel.git] / mm / filemap.c

diff --git a/mm/filemap.c b/mm/filemap.c
index 3247b4208034723c82ad05f0ca4cc880cbdc91d9..65b4b6e7f7bde69620b73af705ecca33629a8f79 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -239,14 +239,16 @@ void __delete_from_page_cache(struct page *page, void *shadow)
        /* Leave page->index set: truncation lookup relies upon it */
 
        /* hugetlb pages do not participate in page cache accounting. */
-       if (!PageHuge(page))
-               __mod_node_page_state(page_pgdat(page), NR_FILE_PAGES, -nr);
+       if (PageHuge(page))
+               return;
+
+       __mod_node_page_state(page_pgdat(page), NR_FILE_PAGES, -nr);
        if (PageSwapBacked(page)) {
                __mod_node_page_state(page_pgdat(page), NR_SHMEM, -nr);
                if (PageTransHuge(page))
                        __dec_node_page_state(page, NR_SHMEM_THPS);
        } else {
-               VM_BUG_ON_PAGE(PageTransHuge(page) && !PageHuge(page), page);
+               VM_BUG_ON_PAGE(PageTransHuge(page), page);
        }
 
        /*
@@ -883,6 +885,7 @@ void __init pagecache_init(void)
        page_writeback_init();
 }
 
+/* This has the same layout as wait_bit_key - see fs/cachefiles/rdwr.c */
 struct wait_page_key {
        struct page *page;
        int bit_nr;
@@ -907,8 +910,10 @@ static int wake_page_function(wait_queue_entry_t *wait, unsigned mode, int sync,
 
        if (wait_page->bit_nr != key->bit_nr)
                return 0;
+
+       /* Stop walking if it's locked */
        if (test_bit(key->bit_nr, &key->page->flags))
-               return 0;
+               return -1;
 
        return autoremove_wake_function(wait, mode, sync, key);
 }
@@ -962,6 +967,7 @@ static inline int wait_on_page_bit_common(wait_queue_head_t *q,
        int ret = 0;
 
        init_wait(wait);
+       wait->flags = lock ? WQ_FLAG_EXCLUSIVE : 0;
        wait->func = wake_page_function;
        wait_page.page = page;
        wait_page.bit_nr = bit_nr;
@@ -970,10 +976,7 @@ static inline int wait_on_page_bit_common(wait_queue_head_t *q,
                spin_lock_irq(&q->lock);
 
                if (likely(list_empty(&wait->entry))) {
-                       if (lock)
-                               __add_wait_queue_entry_tail_exclusive(q, wait);
-                       else
-                               __add_wait_queue(q, wait);
+                       __add_wait_queue_entry_tail(q, wait);
                        SetPageWaiters(page);
                }
 
@@ -983,10 +986,6 @@ static inline int wait_on_page_bit_common(wait_queue_head_t *q,
 
                if (likely(test_bit(bit_nr, &page->flags))) {
                        io_schedule();
-                       if (unlikely(signal_pending_state(state, current))) {
-                               ret = -EINTR;
-                               break;
-                       }
                }
 
                if (lock) {
@@ -996,6 +995,11 @@ static inline int wait_on_page_bit_common(wait_queue_head_t *q,
                        if (!test_bit(bit_nr, &page->flags))
                                break;
                }
+
+               if (unlikely(signal_pending_state(state, current))) {
+                       ret = -EINTR;
+                       break;
+               }
        }
 
        finish_wait(q, wait);
@@ -1037,7 +1041,7 @@ void add_page_wait_queue(struct page *page, wait_queue_entry_t *waiter)
        unsigned long flags;
 
        spin_lock_irqsave(&q->lock, flags);
-       __add_wait_queue(q, waiter);
+       __add_wait_queue_entry_tail(q, waiter);
        SetPageWaiters(page);
        spin_unlock_irqrestore(&q->lock, flags);
 }