mm/page_alloc: prevent MIGRATE_RESERVE pages from being misplaced

[platform/adaptation/renesas_rcar/renesas_kernel.git] / mm / backing-dev.c

diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index e04454c..09d9591 100644 (file)
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -180,7 +180,8 @@ static ssize_t name##_show(struct device *dev,                              \
        struct backing_dev_info *bdi = dev_get_drvdata(dev);            \
                                                                        \
        return snprintf(page, PAGE_SIZE-1, "%lld\n", (long long)expr);  \
-}
+}                                                                      \
+static DEVICE_ATTR_RW(name);
 
 BDI_SHOW(read_ahead_kb, K(bdi->ra_pages))
 
@@ -231,14 +232,16 @@ static ssize_t stable_pages_required_show(struct device *dev,
        return snprintf(page, PAGE_SIZE-1, "%d\n",
                        bdi_cap_stable_pages_required(bdi) ? 1 : 0);
 }
+static DEVICE_ATTR_RO(stable_pages_required);
 
-static struct device_attribute bdi_dev_attrs[] = {
-       __ATTR_RW(read_ahead_kb),
-       __ATTR_RW(min_ratio),
-       __ATTR_RW(max_ratio),
-       __ATTR_RO(stable_pages_required),
-       __ATTR_NULL,
+static struct attribute *bdi_dev_attrs[] = {
+       &dev_attr_read_ahead_kb.attr,
+       &dev_attr_min_ratio.attr,
+       &dev_attr_max_ratio.attr,
+       &dev_attr_stable_pages_required.attr,
+       NULL,
 };
+ATTRIBUTE_GROUPS(bdi_dev);
 
 static __init int bdi_class_init(void)
 {
@@ -246,7 +249,7 @@ static __init int bdi_class_init(void)
        if (IS_ERR(bdi_class))
                return PTR_ERR(bdi_class);
 
-       bdi_class->dev_attrs = bdi_dev_attrs;
+       bdi_class->dev_groups = bdi_dev_groups;
        bdi_debug_init();
        return 0;
 }
@@ -285,13 +288,19 @@ int bdi_has_dirty_io(struct backing_dev_info *bdi)
  * Note, we wouldn't bother setting up the timer, but this function is on the
  * fast-path (used by '__mark_inode_dirty()'), so we save few context switches
  * by delaying the wake-up.
+ *
+ * We have to be careful not to postpone flush work if it is scheduled for
+ * earlier. Thus we use queue_delayed_work().
  */
 void bdi_wakeup_thread_delayed(struct backing_dev_info *bdi)
 {
        unsigned long timeout;
 
        timeout = msecs_to_jiffies(dirty_writeback_interval * 10);
-       mod_delayed_work(bdi_wq, &bdi->wb.dwork, timeout);
+       spin_lock_bh(&bdi->wb_lock);
+       if (test_bit(BDI_registered, &bdi->state))
+               queue_delayed_work(bdi_wq, &bdi->wb.dwork, timeout);
+       spin_unlock_bh(&bdi->wb_lock);
 }
 
 /*
@@ -304,9 +313,6 @@ static void bdi_remove_from_list(struct backing_dev_info *bdi)
        spin_unlock_bh(&bdi_lock);
 
        synchronize_rcu_expedited();
-
-       /* bdi_list is now unused, clear it to mark @bdi dying */
-       INIT_LIST_HEAD(&bdi->bdi_list);
 }
 
 int bdi_register(struct backing_dev_info *bdi, struct device *parent,
@@ -357,6 +363,11 @@ static void bdi_wb_shutdown(struct backing_dev_info *bdi)
         */
        bdi_remove_from_list(bdi);
 
+       /* Make sure nobody queues further work */
+       spin_lock_bh(&bdi->wb_lock);
+       clear_bit(BDI_registered, &bdi->state);
+       spin_unlock_bh(&bdi->wb_lock);
+
        /*
         * Drain work list and shutdown the delayed_work.  At this point,
         * @bdi->bdi_list is empty telling bdi_Writeback_workfn() that @bdi
@@ -649,7 +660,7 @@ int pdflush_proc_obsolete(struct ctl_table *table, int write,
 {
        char kbuf[] = "0\n";
 
-       if (*ppos) {
+       if (*ppos || *lenp < sizeof(kbuf)) {
                *lenp = 0;
                return 0;
        }