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Diffstat (limited to 'drivers/dax/bus.c')
-rw-r--r--drivers/dax/bus.c255
1 files changed, 181 insertions, 74 deletions
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
index 1ff1ab5fa1..f24b67c64d 100644
--- a/drivers/dax/bus.c
+++ b/drivers/dax/bus.c
@@ -12,6 +12,18 @@
static DEFINE_MUTEX(dax_bus_lock);
+/*
+ * All changes to the dax region configuration occur with this lock held
+ * for write.
+ */
+DECLARE_RWSEM(dax_region_rwsem);
+
+/*
+ * All changes to the dax device configuration occur with this lock held
+ * for write.
+ */
+DECLARE_RWSEM(dax_dev_rwsem);
+
#define DAX_NAME_LEN 30
struct dax_id {
struct list_head list;
@@ -180,7 +192,7 @@ static u64 dev_dax_size(struct dev_dax *dev_dax)
u64 size = 0;
int i;
- device_lock_assert(&dev_dax->dev);
+ lockdep_assert_held(&dax_dev_rwsem);
for (i = 0; i < dev_dax->nr_range; i++)
size += range_len(&dev_dax->ranges[i].range);
@@ -194,8 +206,15 @@ static int dax_bus_probe(struct device *dev)
struct dev_dax *dev_dax = to_dev_dax(dev);
struct dax_region *dax_region = dev_dax->region;
int rc;
+ u64 size;
- if (dev_dax_size(dev_dax) == 0 || dev_dax->id < 0)
+ rc = down_read_interruptible(&dax_dev_rwsem);
+ if (rc)
+ return rc;
+ size = dev_dax_size(dev_dax);
+ up_read(&dax_dev_rwsem);
+
+ if (size == 0 || dev_dax->id < 0)
return -ENXIO;
rc = dax_drv->probe(dev_dax);
@@ -222,7 +241,7 @@ static void dax_bus_remove(struct device *dev)
dax_drv->remove(dev_dax);
}
-static struct bus_type dax_bus_type = {
+static const struct bus_type dax_bus_type = {
.name = "dax",
.uevent = dax_bus_uevent,
.match = dax_bus_match,
@@ -250,7 +269,7 @@ static ssize_t id_show(struct device *dev,
{
struct dax_region *dax_region = dev_get_drvdata(dev);
- return sprintf(buf, "%d\n", dax_region->id);
+ return sysfs_emit(buf, "%d\n", dax_region->id);
}
static DEVICE_ATTR_RO(id);
@@ -259,8 +278,8 @@ static ssize_t region_size_show(struct device *dev,
{
struct dax_region *dax_region = dev_get_drvdata(dev);
- return sprintf(buf, "%llu\n", (unsigned long long)
- resource_size(&dax_region->res));
+ return sysfs_emit(buf, "%llu\n",
+ (unsigned long long)resource_size(&dax_region->res));
}
static struct device_attribute dev_attr_region_size = __ATTR(size, 0444,
region_size_show, NULL);
@@ -270,7 +289,7 @@ static ssize_t region_align_show(struct device *dev,
{
struct dax_region *dax_region = dev_get_drvdata(dev);
- return sprintf(buf, "%u\n", dax_region->align);
+ return sysfs_emit(buf, "%u\n", dax_region->align);
}
static struct device_attribute dev_attr_region_align =
__ATTR(align, 0400, region_align_show, NULL);
@@ -283,7 +302,7 @@ static unsigned long long dax_region_avail_size(struct dax_region *dax_region)
resource_size_t size = resource_size(&dax_region->res);
struct resource *res;
- device_lock_assert(dax_region->dev);
+ lockdep_assert_held(&dax_region_rwsem);
for_each_dax_region_resource(dax_region, res)
size -= resource_size(res);
@@ -295,12 +314,15 @@ static ssize_t available_size_show(struct device *dev,
{
struct dax_region *dax_region = dev_get_drvdata(dev);
unsigned long long size;
+ int rc;
- device_lock(dev);
+ rc = down_read_interruptible(&dax_region_rwsem);
+ if (rc)
+ return rc;
size = dax_region_avail_size(dax_region);
- device_unlock(dev);
+ up_read(&dax_region_rwsem);
- return sprintf(buf, "%llu\n", size);
+ return sysfs_emit(buf, "%llu\n", size);
}
static DEVICE_ATTR_RO(available_size);
@@ -314,10 +336,12 @@ static ssize_t seed_show(struct device *dev,
if (is_static(dax_region))
return -EINVAL;
- device_lock(dev);
+ rc = down_read_interruptible(&dax_region_rwsem);
+ if (rc)
+ return rc;
seed = dax_region->seed;
- rc = sprintf(buf, "%s\n", seed ? dev_name(seed) : "");
- device_unlock(dev);
+ rc = sysfs_emit(buf, "%s\n", seed ? dev_name(seed) : "");
+ up_read(&dax_region_rwsem);
return rc;
}
@@ -333,14 +357,18 @@ static ssize_t create_show(struct device *dev,
if (is_static(dax_region))
return -EINVAL;
- device_lock(dev);
+ rc = down_read_interruptible(&dax_region_rwsem);
+ if (rc)
+ return rc;
youngest = dax_region->youngest;
- rc = sprintf(buf, "%s\n", youngest ? dev_name(youngest) : "");
- device_unlock(dev);
+ rc = sysfs_emit(buf, "%s\n", youngest ? dev_name(youngest) : "");
+ up_read(&dax_region_rwsem);
return rc;
}
+static struct dev_dax *__devm_create_dev_dax(struct dev_dax_data *data);
+
static ssize_t create_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t len)
{
@@ -358,7 +386,9 @@ static ssize_t create_store(struct device *dev, struct device_attribute *attr,
if (val != 1)
return -EINVAL;
- device_lock(dev);
+ rc = down_write_killable(&dax_region_rwsem);
+ if (rc)
+ return rc;
avail = dax_region_avail_size(dax_region);
if (avail == 0)
rc = -ENOSPC;
@@ -369,7 +399,7 @@ static ssize_t create_store(struct device *dev, struct device_attribute *attr,
.id = -1,
.memmap_on_memory = false,
};
- struct dev_dax *dev_dax = devm_create_dev_dax(&data);
+ struct dev_dax *dev_dax = __devm_create_dev_dax(&data);
if (IS_ERR(dev_dax))
rc = PTR_ERR(dev_dax);
@@ -387,7 +417,7 @@ static ssize_t create_store(struct device *dev, struct device_attribute *attr,
rc = len;
}
}
- device_unlock(dev);
+ up_write(&dax_region_rwsem);
return rc;
}
@@ -417,7 +447,7 @@ static void trim_dev_dax_range(struct dev_dax *dev_dax)
struct range *range = &dev_dax->ranges[i].range;
struct dax_region *dax_region = dev_dax->region;
- device_lock_assert(dax_region->dev);
+ lockdep_assert_held_write(&dax_region_rwsem);
dev_dbg(&dev_dax->dev, "delete range[%d]: %#llx:%#llx\n", i,
(unsigned long long)range->start,
(unsigned long long)range->end);
@@ -441,10 +471,12 @@ static void unregister_dev_dax(void *dev)
dev_dbg(dev, "%s\n", __func__);
+ down_write(&dax_region_rwsem);
kill_dev_dax(dev_dax);
device_del(dev);
free_dev_dax_ranges(dev_dax);
put_device(dev);
+ up_write(&dax_region_rwsem);
}
static void dax_region_free(struct kref *kref)
@@ -463,11 +495,10 @@ static void dax_region_put(struct dax_region *dax_region)
/* a return value >= 0 indicates this invocation invalidated the id */
static int __free_dev_dax_id(struct dev_dax *dev_dax)
{
- struct device *dev = &dev_dax->dev;
struct dax_region *dax_region;
int rc = dev_dax->id;
- device_lock_assert(dev);
+ lockdep_assert_held_write(&dax_dev_rwsem);
if (!dev_dax->dyn_id || dev_dax->id < 0)
return -1;
@@ -480,12 +511,13 @@ static int __free_dev_dax_id(struct dev_dax *dev_dax)
static int free_dev_dax_id(struct dev_dax *dev_dax)
{
- struct device *dev = &dev_dax->dev;
int rc;
- device_lock(dev);
+ rc = down_write_killable(&dax_dev_rwsem);
+ if (rc)
+ return rc;
rc = __free_dev_dax_id(dev_dax);
- device_unlock(dev);
+ up_write(&dax_dev_rwsem);
return rc;
}
@@ -522,6 +554,7 @@ static ssize_t delete_store(struct device *dev, struct device_attribute *attr,
device_lock(dev);
device_lock(victim);
dev_dax = to_dev_dax(victim);
+ down_write(&dax_dev_rwsem);
if (victim->driver || dev_dax_size(dev_dax))
rc = -EBUSY;
else {
@@ -541,6 +574,7 @@ static ssize_t delete_store(struct device *dev, struct device_attribute *attr,
} else
rc = -EBUSY;
}
+ up_write(&dax_dev_rwsem);
device_unlock(victim);
/* won the race to invalidate the device, clean it up */
@@ -663,12 +697,9 @@ static void unregister_dax_mapping(void *data)
struct device *dev = data;
struct dax_mapping *mapping = to_dax_mapping(dev);
struct dev_dax *dev_dax = to_dev_dax(dev->parent);
- struct dax_region *dax_region = dev_dax->region;
dev_dbg(dev, "%s\n", __func__);
- device_lock_assert(dax_region->dev);
-
dev_dax->ranges[mapping->range_id].mapping = NULL;
mapping->range_id = -1;
@@ -679,24 +710,22 @@ static struct dev_dax_range *get_dax_range(struct device *dev)
{
struct dax_mapping *mapping = to_dax_mapping(dev);
struct dev_dax *dev_dax = to_dev_dax(dev->parent);
- struct dax_region *dax_region = dev_dax->region;
+ int rc;
- device_lock(dax_region->dev);
+ rc = down_write_killable(&dax_region_rwsem);
+ if (rc)
+ return NULL;
if (mapping->range_id < 0) {
- device_unlock(dax_region->dev);
+ up_write(&dax_region_rwsem);
return NULL;
}
return &dev_dax->ranges[mapping->range_id];
}
-static void put_dax_range(struct dev_dax_range *dax_range)
+static void put_dax_range(void)
{
- struct dax_mapping *mapping = dax_range->mapping;
- struct dev_dax *dev_dax = to_dev_dax(mapping->dev.parent);
- struct dax_region *dax_region = dev_dax->region;
-
- device_unlock(dax_region->dev);
+ up_write(&dax_region_rwsem);
}
static ssize_t start_show(struct device *dev,
@@ -708,8 +737,8 @@ static ssize_t start_show(struct device *dev,
dax_range = get_dax_range(dev);
if (!dax_range)
return -ENXIO;
- rc = sprintf(buf, "%#llx\n", dax_range->range.start);
- put_dax_range(dax_range);
+ rc = sysfs_emit(buf, "%#llx\n", dax_range->range.start);
+ put_dax_range();
return rc;
}
@@ -724,8 +753,8 @@ static ssize_t end_show(struct device *dev,
dax_range = get_dax_range(dev);
if (!dax_range)
return -ENXIO;
- rc = sprintf(buf, "%#llx\n", dax_range->range.end);
- put_dax_range(dax_range);
+ rc = sysfs_emit(buf, "%#llx\n", dax_range->range.end);
+ put_dax_range();
return rc;
}
@@ -740,8 +769,8 @@ static ssize_t pgoff_show(struct device *dev,
dax_range = get_dax_range(dev);
if (!dax_range)
return -ENXIO;
- rc = sprintf(buf, "%#lx\n", dax_range->pgoff);
- put_dax_range(dax_range);
+ rc = sysfs_emit(buf, "%#lx\n", dax_range->pgoff);
+ put_dax_range();
return rc;
}
@@ -775,7 +804,7 @@ static int devm_register_dax_mapping(struct dev_dax *dev_dax, int range_id)
struct device *dev;
int rc;
- device_lock_assert(dax_region->dev);
+ lockdep_assert_held_write(&dax_region_rwsem);
if (dev_WARN_ONCE(&dev_dax->dev, !dax_region->dev->driver,
"region disabled\n"))
@@ -821,7 +850,7 @@ static int alloc_dev_dax_range(struct dev_dax *dev_dax, u64 start,
struct resource *alloc;
int i, rc;
- device_lock_assert(dax_region->dev);
+ lockdep_assert_held_write(&dax_region_rwsem);
/* handle the seed alloc special case */
if (!size) {
@@ -875,13 +904,12 @@ static int adjust_dev_dax_range(struct dev_dax *dev_dax, struct resource *res, r
{
int last_range = dev_dax->nr_range - 1;
struct dev_dax_range *dax_range = &dev_dax->ranges[last_range];
- struct dax_region *dax_region = dev_dax->region;
bool is_shrink = resource_size(res) > size;
struct range *range = &dax_range->range;
struct device *dev = &dev_dax->dev;
int rc;
- device_lock_assert(dax_region->dev);
+ lockdep_assert_held_write(&dax_region_rwsem);
if (dev_WARN_ONCE(dev, !size, "deletion is handled by dev_dax_shrink\n"))
return -EINVAL;
@@ -907,12 +935,15 @@ static ssize_t size_show(struct device *dev,
{
struct dev_dax *dev_dax = to_dev_dax(dev);
unsigned long long size;
+ int rc;
- device_lock(dev);
+ rc = down_read_interruptible(&dax_dev_rwsem);
+ if (rc)
+ return rc;
size = dev_dax_size(dev_dax);
- device_unlock(dev);
+ up_read(&dax_dev_rwsem);
- return sprintf(buf, "%llu\n", size);
+ return sysfs_emit(buf, "%llu\n", size);
}
static bool alloc_is_aligned(struct dev_dax *dev_dax, resource_size_t size)
@@ -1080,17 +1111,27 @@ static ssize_t size_store(struct device *dev, struct device_attribute *attr,
return -EINVAL;
}
- device_lock(dax_region->dev);
+ rc = down_write_killable(&dax_region_rwsem);
+ if (rc)
+ return rc;
if (!dax_region->dev->driver) {
- device_unlock(dax_region->dev);
- return -ENXIO;
+ rc = -ENXIO;
+ goto err_region;
}
- device_lock(dev);
+ rc = down_write_killable(&dax_dev_rwsem);
+ if (rc)
+ goto err_dev;
+
rc = dev_dax_resize(dax_region, dev_dax, val);
- device_unlock(dev);
- device_unlock(dax_region->dev);
- return rc == 0 ? len : rc;
+err_dev:
+ up_write(&dax_dev_rwsem);
+err_region:
+ up_write(&dax_region_rwsem);
+
+ if (rc == 0)
+ return len;
+ return rc;
}
static DEVICE_ATTR_RW(size);
@@ -1138,18 +1179,24 @@ static ssize_t mapping_store(struct device *dev, struct device_attribute *attr,
return rc;
rc = -ENXIO;
- device_lock(dax_region->dev);
+ rc = down_write_killable(&dax_region_rwsem);
+ if (rc)
+ return rc;
if (!dax_region->dev->driver) {
- device_unlock(dax_region->dev);
+ up_write(&dax_region_rwsem);
+ return rc;
+ }
+ rc = down_write_killable(&dax_dev_rwsem);
+ if (rc) {
+ up_write(&dax_region_rwsem);
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);
+ up_write(&dax_dev_rwsem);
+ up_write(&dax_region_rwsem);
return rc == 0 ? len : rc;
}
@@ -1160,7 +1207,7 @@ static ssize_t align_show(struct device *dev,
{
struct dev_dax *dev_dax = to_dev_dax(dev);
- return sprintf(buf, "%d\n", dev_dax->align);
+ return sysfs_emit(buf, "%d\n", dev_dax->align);
}
static ssize_t dev_dax_validate_align(struct dev_dax *dev_dax)
@@ -1196,13 +1243,19 @@ static ssize_t align_store(struct device *dev, struct device_attribute *attr,
if (!dax_align_valid(val))
return -EINVAL;
- device_lock(dax_region->dev);
+ rc = down_write_killable(&dax_region_rwsem);
+ if (rc)
+ return rc;
if (!dax_region->dev->driver) {
- device_unlock(dax_region->dev);
+ up_write(&dax_region_rwsem);
return -ENXIO;
}
- device_lock(dev);
+ rc = down_write_killable(&dax_dev_rwsem);
+ if (rc) {
+ up_write(&dax_region_rwsem);
+ return rc;
+ }
if (dev->driver) {
rc = -EBUSY;
goto out_unlock;
@@ -1214,8 +1267,8 @@ static ssize_t align_store(struct device *dev, struct device_attribute *attr,
if (rc)
dev_dax->align = align_save;
out_unlock:
- device_unlock(dev);
- device_unlock(dax_region->dev);
+ up_write(&dax_dev_rwsem);
+ up_write(&dax_region_rwsem);
return rc == 0 ? len : rc;
}
static DEVICE_ATTR_RW(align);
@@ -1232,7 +1285,7 @@ static ssize_t target_node_show(struct device *dev,
{
struct dev_dax *dev_dax = to_dev_dax(dev);
- return sprintf(buf, "%d\n", dev_dax_target_node(dev_dax));
+ return sysfs_emit(buf, "%d\n", dev_dax_target_node(dev_dax));
}
static DEVICE_ATTR_RO(target_node);
@@ -1248,7 +1301,7 @@ static ssize_t resource_show(struct device *dev,
else
start = dev_dax->ranges[0].range.start;
- return sprintf(buf, "%#llx\n", start);
+ return sysfs_emit(buf, "%#llx\n", start);
}
static DEVICE_ATTR(resource, 0400, resource_show, NULL);
@@ -1259,17 +1312,59 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
* We only ever expect to handle device-dax instances, i.e. the
* @type argument to MODULE_ALIAS_DAX_DEVICE() is always zero
*/
- return sprintf(buf, DAX_DEVICE_MODALIAS_FMT "\n", 0);
+ return sysfs_emit(buf, DAX_DEVICE_MODALIAS_FMT "\n", 0);
}
static DEVICE_ATTR_RO(modalias);
static ssize_t numa_node_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- return sprintf(buf, "%d\n", dev_to_node(dev));
+ return sysfs_emit(buf, "%d\n", dev_to_node(dev));
}
static DEVICE_ATTR_RO(numa_node);
+static ssize_t memmap_on_memory_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct dev_dax *dev_dax = to_dev_dax(dev);
+
+ return sysfs_emit(buf, "%d\n", dev_dax->memmap_on_memory);
+}
+
+static ssize_t memmap_on_memory_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct dev_dax *dev_dax = to_dev_dax(dev);
+ bool val;
+ int rc;
+
+ rc = kstrtobool(buf, &val);
+ if (rc)
+ return rc;
+
+ if (val == true && !mhp_supports_memmap_on_memory()) {
+ dev_dbg(dev, "memmap_on_memory is not available\n");
+ return -EOPNOTSUPP;
+ }
+
+ rc = down_write_killable(&dax_dev_rwsem);
+ if (rc)
+ return rc;
+
+ if (dev_dax->memmap_on_memory != val && dev->driver &&
+ to_dax_drv(dev->driver)->type == DAXDRV_KMEM_TYPE) {
+ up_write(&dax_dev_rwsem);
+ return -EBUSY;
+ }
+
+ dev_dax->memmap_on_memory = val;
+ up_write(&dax_dev_rwsem);
+
+ return len;
+}
+static DEVICE_ATTR_RW(memmap_on_memory);
+
static umode_t dev_dax_visible(struct kobject *kobj, struct attribute *a, int n)
{
struct device *dev = container_of(kobj, struct device, kobj);
@@ -1296,6 +1391,7 @@ static struct attribute *dev_dax_attributes[] = {
&dev_attr_align.attr,
&dev_attr_resource.attr,
&dev_attr_numa_node.attr,
+ &dev_attr_memmap_on_memory.attr,
NULL,
};
@@ -1325,7 +1421,7 @@ static const struct device_type dev_dax_type = {
.groups = dax_attribute_groups,
};
-struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data)
+static struct dev_dax *__devm_create_dev_dax(struct dev_dax_data *data)
{
struct dax_region *dax_region = data->dax_region;
struct device *parent = dax_region->dev;
@@ -1440,6 +1536,17 @@ err_id:
return ERR_PTR(rc);
}
+
+struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data)
+{
+ struct dev_dax *dev_dax;
+
+ down_write(&dax_region_rwsem);
+ dev_dax = __devm_create_dev_dax(data);
+ up_write(&dax_region_rwsem);
+
+ return dev_dax;
+}
EXPORT_SYMBOL_GPL(devm_create_dev_dax);
int __dax_driver_register(struct dax_device_driver *dax_drv,
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-04 14:03:40 +0000