libnvdimm/dimm: Avoid race between probe and available_slots_show()

[linux-2.6-microblaze.git] / drivers / nvdimm / dimm_devs.c

diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
index b59032e..9d20857 100644 (file)
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -335,16 +335,16 @@ static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR_RO(state);
 
-static ssize_t available_slots_show(struct device *dev,
-               struct device_attribute *attr, char *buf)
+static ssize_t __available_slots_show(struct nvdimm_drvdata *ndd, char *buf)
 {
-       struct nvdimm_drvdata *ndd = dev_get_drvdata(dev);
+       struct device *dev;
        ssize_t rc;
        u32 nfree;
 
        if (!ndd)
                return -ENXIO;
 
+       dev = ndd->dev;
        nvdimm_bus_lock(dev);
        nfree = nd_label_nfree(ndd);
        if (nfree - 1 > nfree) {
@@ -356,6 +356,18 @@ static ssize_t available_slots_show(struct device *dev,
        nvdimm_bus_unlock(dev);
        return rc;
 }
+
+static ssize_t available_slots_show(struct device *dev,
+                                   struct device_attribute *attr, char *buf)
+{
+       ssize_t rc;
+
+       nd_device_lock(dev);
+       rc = __available_slots_show(dev_get_drvdata(dev), buf);
+       nd_device_unlock(dev);
+
+       return rc;
+}
 static DEVICE_ATTR_RO(available_slots);
 
 __weak ssize_t security_show(struct device *dev,