device-dax: Fix range release
[linux-2.6-microblaze.git] / drivers / dax / bus.c
index 005fa3e..720cd14 100644 (file)
@@ -230,14 +230,15 @@ static ssize_t region_size_show(struct device *dev,
 static struct device_attribute dev_attr_region_size = __ATTR(size, 0444,
                region_size_show, NULL);
 
-static ssize_t align_show(struct device *dev,
+static ssize_t region_align_show(struct device *dev,
                struct device_attribute *attr, char *buf)
 {
        struct dax_region *dax_region = dev_get_drvdata(dev);
 
        return sprintf(buf, "%u\n", dax_region->align);
 }
-static DEVICE_ATTR_RO(align);
+static struct device_attribute dev_attr_region_align =
+               __ATTR(align, 0400, region_align_show, NULL);
 
 #define for_each_dax_region_resource(dax_region, res) \
        for (res = (dax_region)->res.child; res; res = res->sibling)
@@ -366,19 +367,28 @@ void kill_dev_dax(struct dev_dax *dev_dax)
 }
 EXPORT_SYMBOL_GPL(kill_dev_dax);
 
-static void free_dev_dax_ranges(struct dev_dax *dev_dax)
+static void trim_dev_dax_range(struct dev_dax *dev_dax)
 {
+       int i = dev_dax->nr_range - 1;
+       struct range *range = &dev_dax->ranges[i].range;
        struct dax_region *dax_region = dev_dax->region;
-       int i;
 
        device_lock_assert(dax_region->dev);
-       for (i = 0; i < dev_dax->nr_range; i++) {
-               struct range *range = &dev_dax->ranges[i].range;
-
-               __release_region(&dax_region->res, range->start,
-                               range_len(range));
+       dev_dbg(&dev_dax->dev, "delete range[%d]: %#llx:%#llx\n", i,
+               (unsigned long long)range->start,
+               (unsigned long long)range->end);
+
+       __release_region(&dax_region->res, range->start, range_len(range));
+       if (--dev_dax->nr_range == 0) {
+               kfree(dev_dax->ranges);
+               dev_dax->ranges = NULL;
        }
-       dev_dax->nr_range = 0;
+}
+
+static void free_dev_dax_ranges(struct dev_dax *dev_dax)
+{
+       while (dev_dax->nr_range)
+               trim_dev_dax_range(dev_dax);
 }
 
 static void unregister_dev_dax(void *dev)
@@ -488,7 +498,7 @@ static umode_t dax_region_visible(struct kobject *kobj, struct attribute *a,
 static struct attribute *dax_region_attributes[] = {
        &dev_attr_available_size.attr,
        &dev_attr_region_size.attr,
-       &dev_attr_align.attr,
+       &dev_attr_region_align.attr,
        &dev_attr_create.attr,
        &dev_attr_seed.attr,
        &dev_attr_delete.attr,
@@ -803,15 +813,10 @@ static int alloc_dev_dax_range(struct dev_dax *dev_dax, u64 start,
                return 0;
 
        rc = devm_register_dax_mapping(dev_dax, dev_dax->nr_range - 1);
-       if (rc) {
-               dev_dbg(dev, "delete range[%d]: %pa:%pa\n", dev_dax->nr_range - 1,
-                               &alloc->start, &alloc->end);
-               dev_dax->nr_range--;
-               __release_region(res, alloc->start, resource_size(alloc));
-               return rc;
-       }
+       if (rc)
+               trim_dev_dax_range(dev_dax);
 
-       return 0;
+       return rc;
 }
 
 static int adjust_dev_dax_range(struct dev_dax *dev_dax, struct resource *res, resource_size_t size)
@@ -858,15 +863,13 @@ static ssize_t size_show(struct device *dev,
        return sprintf(buf, "%llu\n", size);
 }
 
-static bool alloc_is_aligned(struct dax_region *dax_region,
-               resource_size_t size)
+static bool alloc_is_aligned(struct dev_dax *dev_dax, resource_size_t size)
 {
        /*
         * The minimum mapping granularity for a device instance is a
         * single subsection, unless the arch says otherwise.
         */
-       return IS_ALIGNED(size, max_t(unsigned long, dax_region->align,
-                               memremap_compat_align()));
+       return IS_ALIGNED(size, max_t(unsigned long, dev_dax->align, memremap_compat_align()));
 }
 
 static int dev_dax_shrink(struct dev_dax *dev_dax, resource_size_t size)
@@ -886,12 +889,7 @@ static int dev_dax_shrink(struct dev_dax *dev_dax, resource_size_t size)
                if (shrink >= range_len(range)) {
                        devm_release_action(dax_region->dev,
                                        unregister_dax_mapping, &mapping->dev);
-                       __release_region(&dax_region->res, range->start,
-                                       range_len(range));
-                       dev_dax->nr_range--;
-                       dev_dbg(dev, "delete range[%d]: %#llx:%#llx\n", i,
-                                       (unsigned long long) range->start,
-                                       (unsigned long long) range->end);
+                       trim_dev_dax_range(dev_dax);
                        to_shrink -= shrink;
                        if (!to_shrink)
                                break;
@@ -961,7 +959,7 @@ static ssize_t dev_dax_resize(struct dax_region *dax_region,
                return dev_dax_shrink(dev_dax, size);
 
        to_alloc = size - dev_size;
-       if (dev_WARN_ONCE(dev, !alloc_is_aligned(dax_region, to_alloc),
+       if (dev_WARN_ONCE(dev, !alloc_is_aligned(dev_dax, to_alloc),
                        "resize of %pa misaligned\n", &to_alloc))
                return -ENXIO;
 
@@ -1025,7 +1023,7 @@ static ssize_t size_store(struct device *dev, struct device_attribute *attr,
        if (rc)
                return rc;
 
-       if (!alloc_is_aligned(dax_region, val)) {
+       if (!alloc_is_aligned(dev_dax, val)) {
                dev_dbg(dev, "%s: size: %lld misaligned\n", __func__, val);
                return -EINVAL;
        }
@@ -1044,6 +1042,132 @@ static ssize_t size_store(struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR_RW(size);
 
+static ssize_t range_parse(const char *opt, size_t len, struct range *range)
+{
+       unsigned long long addr = 0;
+       char *start, *end, *str;
+       ssize_t rc = EINVAL;
+
+       str = kstrdup(opt, GFP_KERNEL);
+       if (!str)
+               return rc;
+
+       end = str;
+       start = strsep(&end, "-");
+       if (!start || !end)
+               goto err;
+
+       rc = kstrtoull(start, 16, &addr);
+       if (rc)
+               goto err;
+       range->start = addr;
+
+       rc = kstrtoull(end, 16, &addr);
+       if (rc)
+               goto err;
+       range->end = addr;
+
+err:
+       kfree(str);
+       return rc;
+}
+
+static ssize_t mapping_store(struct device *dev, struct device_attribute *attr,
+               const char *buf, size_t len)
+{
+       struct dev_dax *dev_dax = to_dev_dax(dev);
+       struct dax_region *dax_region = dev_dax->region;
+       size_t to_alloc;
+       struct range r;
+       ssize_t rc;
+
+       rc = range_parse(buf, len, &r);
+       if (rc)
+               return rc;
+
+       rc = -ENXIO;
+       device_lock(dax_region->dev);
+       if (!dax_region->dev->driver) {
+               device_unlock(dax_region->dev);
+               return rc;
+       }
+       device_lock(dev);
+
+       to_alloc = range_len(&r);
+       if (alloc_is_aligned(dev_dax, to_alloc))
+               rc = alloc_dev_dax_range(dev_dax, r.start, to_alloc);
+       device_unlock(dev);
+       device_unlock(dax_region->dev);
+
+       return rc == 0 ? len : rc;
+}
+static DEVICE_ATTR_WO(mapping);
+
+static ssize_t align_show(struct device *dev,
+               struct device_attribute *attr, char *buf)
+{
+       struct dev_dax *dev_dax = to_dev_dax(dev);
+
+       return sprintf(buf, "%d\n", dev_dax->align);
+}
+
+static ssize_t dev_dax_validate_align(struct dev_dax *dev_dax)
+{
+       struct device *dev = &dev_dax->dev;
+       int i;
+
+       for (i = 0; i < dev_dax->nr_range; i++) {
+               size_t len = range_len(&dev_dax->ranges[i].range);
+
+               if (!alloc_is_aligned(dev_dax, len)) {
+                       dev_dbg(dev, "%s: align %u invalid for range %d\n",
+                               __func__, dev_dax->align, i);
+                       return -EINVAL;
+               }
+       }
+
+       return 0;
+}
+
+static ssize_t align_store(struct device *dev, struct device_attribute *attr,
+               const char *buf, size_t len)
+{
+       struct dev_dax *dev_dax = to_dev_dax(dev);
+       struct dax_region *dax_region = dev_dax->region;
+       unsigned long val, align_save;
+       ssize_t rc;
+
+       rc = kstrtoul(buf, 0, &val);
+       if (rc)
+               return -ENXIO;
+
+       if (!dax_align_valid(val))
+               return -EINVAL;
+
+       device_lock(dax_region->dev);
+       if (!dax_region->dev->driver) {
+               device_unlock(dax_region->dev);
+               return -ENXIO;
+       }
+
+       device_lock(dev);
+       if (dev->driver) {
+               rc = -EBUSY;
+               goto out_unlock;
+       }
+
+       align_save = dev_dax->align;
+       dev_dax->align = val;
+       rc = dev_dax_validate_align(dev_dax);
+       if (rc)
+               dev_dax->align = align_save;
+out_unlock:
+       device_unlock(dev);
+       device_unlock(dax_region->dev);
+       return rc == 0 ? len : rc;
+}
+static DEVICE_ATTR_RW(align);
+
 static int dev_dax_target_node(struct dev_dax *dev_dax)
 {
        struct dax_region *dax_region = dev_dax->region;
@@ -1104,7 +1228,10 @@ static umode_t dev_dax_visible(struct kobject *kobj, struct attribute *a, int n)
                return 0;
        if (a == &dev_attr_numa_node.attr && !IS_ENABLED(CONFIG_NUMA))
                return 0;
-       if (a == &dev_attr_size.attr && is_static(dax_region))
+       if (a == &dev_attr_mapping.attr && is_static(dax_region))
+               return 0;
+       if ((a == &dev_attr_align.attr ||
+            a == &dev_attr_size.attr) && is_static(dax_region))
                return 0444;
        return a->mode;
 }
@@ -1112,7 +1239,9 @@ static umode_t dev_dax_visible(struct kobject *kobj, struct attribute *a, int n)
 static struct attribute *dev_dax_attributes[] = {
        &dev_attr_modalias.attr,
        &dev_attr_size.attr,
+       &dev_attr_mapping.attr,
        &dev_attr_target_node.attr,
+       &dev_attr_align.attr,
        &dev_attr_resource.attr,
        &dev_attr_numa_node.attr,
        NULL,
@@ -1137,7 +1266,6 @@ static void dev_dax_release(struct device *dev)
        put_dax(dax_dev);
        free_dev_dax_id(dev_dax);
        dax_region_put(dax_region);
-       kfree(dev_dax->ranges);
        kfree(dev_dax->pgmap);
        kfree(dev_dax);
 }
@@ -1218,6 +1346,7 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data)
 
        dev_dax->dax_dev = dax_dev;
        dev_dax->target_node = dax_region->target_node;
+       dev_dax->align = dax_region->align;
        ida_init(&dev_dax->ida);
        kref_get(&dax_region->kref);