Merge branch 'akpm/master'

4 files changed, 48 insertions, 2 deletions

diff --git a/Documentation/ABI/testing/sysfs-class-bdi b/Documentation/ABI/testing/sysfs-class-bdi
index d773d5697cf5..3187a18af6da 100644
--- a/Documentation/ABI/testing/sysfs-class-bdi
+++ b/Documentation/ABI/testing/sysfs-class-bdi
@@ -53,3 +53,11 @@ stable_pages_required (read-only)
 
 	If set, the backing device requires that all pages comprising a write
 	request must not be changed until writeout is complete.
+
+strictlimit (read-write)
+
+	Forces per-BDI checks for the share of given device in the write-back
+	cache even before the global background dirty limit is reached. This
+	is useful in situations where the global limit is much higher than
+	affordable for given relatively slow (or untrusted) device. Turning
+	strictlimit on has no visible effect if max_ratio is equal to 100%.
diff --git a/drivers/gpio/gpio-zevio.c b/drivers/gpio/gpio-zevio.c
index f769cd53f4e4..e3856c62d3c2 100644
--- a/drivers/gpio/gpio-zevio.c
+++ b/drivers/gpio/gpio-zevio.c
@@ -18,6 +18,10 @@
 #include <linux/slab.h>
 #include <linux/gpio.h>
 
+#ifndef IOMEM
+#define IOMEM(x)    ((void __force __iomem *)(x))
+#endif
+
 /*
  * Memory layout:
  * This chip has four gpio sections, each controls 8 GPIOs.
diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c
index 47249a30eae3..20f766afa4c7 100644
--- a/drivers/w1/w1_int.c
+++ b/drivers/w1/w1_int.c
@@ -91,8 +91,7 @@ static struct w1_master *w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
 	err = device_register(&dev->dev);
 	if (err) {
 		pr_err("Failed to register master device. err=%d\n", err);
-		memset(dev, 0, sizeof(struct w1_master));
-		kfree(dev);
+		put_device(&dev->dev);
 		dev = NULL;
 	}
 
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 0ae0df55000b..06715eb66bff 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -234,11 +234,46 @@ static ssize_t stable_pages_required_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(stable_pages_required);
 
+static ssize_t strictlimit_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct backing_dev_info *bdi = dev_get_drvdata(dev);
+	unsigned int val;
+	ssize_t ret;
+
+	ret = kstrtouint(buf, 10, &val);
+	if (ret < 0)
+		return ret;
+
+	switch (val) {
+	case 0:
+		bdi->capabilities &= ~BDI_CAP_STRICTLIMIT;
+		break;
+	case 1:
+		bdi->capabilities |= BDI_CAP_STRICTLIMIT;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return count;
+}
+static ssize_t strictlimit_show(struct device *dev,
+		struct device_attribute *attr, char *page)
+{
+	struct backing_dev_info *bdi = dev_get_drvdata(dev);
+
+	return snprintf(page, PAGE_SIZE-1, "%d\n",
+			!!(bdi->capabilities & BDI_CAP_STRICTLIMIT));
+}
+static DEVICE_ATTR_RW(strictlimit);
+
 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,
+	&dev_attr_strictlimit.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(bdi_dev);