@@ -21,6 +21,8 @@ cxled_to_mds(struct cxl_endpoint_decoder *cxled)
return container_of(cxlds, struct cxl_memdev_state, cxlds);
}
+int cxl_region_invalidate_memregion(struct cxl_region *cxlr);
+
#ifdef CONFIG_CXL_REGION
extern struct device_attribute dev_attr_create_pmem_region;
extern struct device_attribute dev_attr_create_ram_region;
@@ -117,6 +117,12 @@ static void region_extent_unregister(void *ext)
dev_dbg(®ion_extent->dev, "DAX region rm extent HPA [range 0x%016llx-0x%016llx]\n",
region_extent->hpa_range.start, region_extent->hpa_range.end);
+ /*
+ * Extent is not in use or an error has occur. No mappings
+ * exist at this point. Write and invalidate caches to ensure
+ * the device has all data prior to final release.
+ */
+ cxl_region_invalidate_memregion(region_extent->cxlr_dax->cxlr);
device_unregister(®ion_extent->dev);
}
@@ -270,20 +276,67 @@ static void calc_hpa_range(struct cxl_endpoint_decoder *cxled,
hpa_range->end = hpa_range->start + range_len(dpa_range) - 1;
}
+static int cxlr_notify_extent(struct cxl_region *cxlr, enum dc_event event,
+ struct region_extent *region_extent)
+{
+ struct device *dev = &cxlr->cxlr_dax->dev;
+ struct cxl_notify_data notify_data;
+ struct cxl_driver *driver;
+
+ dev_dbg(dev, "Trying notify: type %d HPA [range 0x%016llx-0x%016llx]\n",
+ event,
+ region_extent->hpa_range.start, region_extent->hpa_range.end);
+
+ guard(device)(dev);
+
+ /*
+ * The lack of a driver indicates a notification has failed. No user
+ * space coordination was possible.
+ */
+ if (!dev->driver)
+ return 0;
+ driver = to_cxl_drv(dev->driver);
+ if (!driver->notify)
+ return 0;
+
+ notify_data = (struct cxl_notify_data) {
+ .event = event,
+ .region_extent = region_extent,
+ };
+
+ dev_dbg(dev, "Notify: type %d HPA [range 0x%016llx-0x%016llx]\n",
+ event,
+ region_extent->hpa_range.start, region_extent->hpa_range.end);
+ return driver->notify(dev, ¬ify_data);
+}
+
+struct rm_data {
+ struct cxl_region *cxlr;
+ struct range *range;
+};
+
static int cxlr_rm_extent(struct device *dev, void *data)
{
struct region_extent *region_extent = to_region_extent(dev);
- struct range *region_hpa_range = data;
+ struct rm_data *rm_data = data;
+ int rc;
if (!region_extent)
return 0;
/*
- * Any extent which 'touches' the released range is removed.
+ * Any extent which 'touches' the released range is attempted to be
+ * removed.
*/
- if (range_overlaps(region_hpa_range, ®ion_extent->hpa_range)) {
+ if (range_overlaps(rm_data->range, ®ion_extent->hpa_range)) {
+ struct cxl_region *cxlr = rm_data->cxlr;
+
dev_dbg(dev, "Remove region extent HPA [range 0x%016llx-0x%016llx]\n",
region_extent->hpa_range.start, region_extent->hpa_range.end);
+ rc = cxlr_notify_extent(cxlr, DCD_RELEASE_CAPACITY, region_extent);
+ if (rc == -EBUSY)
+ return 0;
+
region_rm_extent(region_extent);
}
return 0;
@@ -328,8 +381,13 @@ int cxl_rm_extent(struct cxl_memdev_state *mds, struct cxl_extent *extent)
calc_hpa_range(cxled, cxlr->cxlr_dax, &dpa_range, &hpa_range);
+ struct rm_data rm_data = {
+ .cxlr = cxlr,
+ .range = &hpa_range,
+ };
+
/* Remove region extents which overlap */
- return device_for_each_child(&cxlr->cxlr_dax->dev, &hpa_range,
+ return device_for_each_child(&cxlr->cxlr_dax->dev, &rm_data,
cxlr_rm_extent);
}
@@ -354,8 +412,23 @@ static int cxlr_add_extent(struct cxl_dax_region *cxlr_dax,
return rc;
}
- /* device model handles freeing region_extent */
- return online_region_extent(region_extent);
+ /* Ensure caches are clean prior onlining */
+ cxl_region_invalidate_memregion(cxlr_dax->cxlr);
+
+ rc = online_region_extent(region_extent);
+ /* device model handled freeing region_extent */
+ if (rc)
+ return rc;
+
+ rc = cxlr_notify_extent(cxlr_dax->cxlr, DCD_ADD_CAPACITY, region_extent);
+ /*
+ * The region device was briefly live but DAX layer ensures it was not
+ * used
+ */
+ if (rc)
+ region_rm_extent(region_extent);
+
+ return rc;
}
/* Callers are expected to ensure cxled has been attached to a region */
@@ -223,7 +223,7 @@ static struct cxl_region_ref *cxl_rr_load(struct cxl_port *port,
return xa_load(&port->regions, (unsigned long)cxlr);
}
-static int cxl_region_invalidate_memregion(struct cxl_region *cxlr)
+int cxl_region_invalidate_memregion(struct cxl_region *cxlr)
{
if (!cpu_cache_has_invalidate_memregion()) {
if (IS_ENABLED(CONFIG_CXL_REGION_INVALIDATION_TEST)) {
@@ -918,10 +918,16 @@ bool is_cxl_region(struct device *dev);
extern struct bus_type cxl_bus_type;
+struct cxl_notify_data {
+ enum dc_event event;
+ struct region_extent *region_extent;
+};
+
struct cxl_driver {
const char *name;
int (*probe)(struct device *dev);
void (*remove)(struct device *dev);
+ int (*notify)(struct device *dev, struct cxl_notify_data *notify_data);
struct device_driver drv;
int id;
};
@@ -183,6 +183,93 @@ static bool is_sparse(struct dax_region *dax_region)
return (dax_region->res.flags & IORESOURCE_DAX_SPARSE_CAP) != 0;
}
+static void __dax_release_resource(struct dax_resource *dax_resource)
+{
+ struct dax_region *dax_region = dax_resource->region;
+
+ lockdep_assert_held_write(&dax_region_rwsem);
+ dev_dbg(dax_region->dev, "Extent release resource %pr\n",
+ dax_resource->res);
+ if (dax_resource->res)
+ __release_region(&dax_region->res, dax_resource->res->start,
+ resource_size(dax_resource->res));
+ dax_resource->res = NULL;
+}
+
+static void dax_release_resource(void *res)
+{
+ struct dax_resource *dax_resource = res;
+
+ guard(rwsem_write)(&dax_region_rwsem);
+ __dax_release_resource(dax_resource);
+ kfree(dax_resource);
+}
+
+int dax_region_add_resource(struct dax_region *dax_region,
+ struct device *device,
+ resource_size_t start, resource_size_t length)
+{
+ struct resource *new_resource;
+ int rc;
+
+ struct dax_resource *dax_resource __free(kfree) =
+ kzalloc(sizeof(*dax_resource), GFP_KERNEL);
+ if (!dax_resource)
+ return -ENOMEM;
+
+ guard(rwsem_write)(&dax_region_rwsem);
+
+ dev_dbg(dax_region->dev, "DAX region resource %pr\n", &dax_region->res);
+ new_resource = __request_region(&dax_region->res, start, length, "extent", 0);
+ if (!new_resource) {
+ dev_err(dax_region->dev, "Failed to add region s:%pa l:%pa\n",
+ &start, &length);
+ return -ENOSPC;
+ }
+
+ dev_dbg(dax_region->dev, "add resource %pr\n", new_resource);
+ dax_resource->region = dax_region;
+ dax_resource->res = new_resource;
+
+ /*
+ * open code devm_add_action_or_reset() to avoid recursive write lock
+ * of dax_region_rwsem in the error case.
+ */
+ rc = devm_add_action(device, dax_release_resource, dax_resource);
+ if (rc) {
+ __dax_release_resource(dax_resource);
+ return rc;
+ }
+
+ dev_set_drvdata(device, no_free_ptr(dax_resource));
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dax_region_add_resource);
+
+int dax_region_rm_resource(struct dax_region *dax_region,
+ struct device *dev)
+{
+ struct dax_resource *dax_resource;
+
+ guard(rwsem_write)(&dax_region_rwsem);
+
+ dax_resource = dev_get_drvdata(dev);
+ if (!dax_resource)
+ return 0;
+
+ if (dax_resource->use_cnt)
+ return -EBUSY;
+
+ /*
+ * release the resource under dax_region_rwsem to avoid races with
+ * users trying to use the extent
+ */
+ __dax_release_resource(dax_resource);
+ dev_set_drvdata(dev, NULL);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dax_region_rm_resource);
+
bool static_dev_dax(struct dev_dax *dev_dax)
{
return is_static(dev_dax->region);
@@ -296,19 +383,41 @@ static ssize_t region_align_show(struct device *dev,
static struct device_attribute dev_attr_region_align =
__ATTR(align, 0400, region_align_show, NULL);
+resource_size_t
+dax_avail_size(struct resource *dax_resource)
+{
+ resource_size_t rc;
+ struct resource *used_res;
+
+ rc = resource_size(dax_resource);
+ for_each_child_resource(dax_resource, used_res)
+ rc -= resource_size(used_res);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(dax_avail_size);
+
#define for_each_dax_region_resource(dax_region, res) \
for (res = (dax_region)->res.child; res; res = res->sibling)
static unsigned long long dax_region_avail_size(struct dax_region *dax_region)
{
- resource_size_t size = resource_size(&dax_region->res);
+ resource_size_t size;
struct resource *res;
lockdep_assert_held(&dax_region_rwsem);
- if (is_sparse(dax_region))
- return 0;
+ if (is_sparse(dax_region)) {
+ /*
+ * Children of a sparse region represent available space not
+ * used space.
+ */
+ size = 0;
+ for_each_dax_region_resource(dax_region, res)
+ size += dax_avail_size(res);
+ return size;
+ }
+ size = resource_size(&dax_region->res);
for_each_dax_region_resource(dax_region, res)
size -= resource_size(res);
return size;
@@ -449,15 +558,26 @@ EXPORT_SYMBOL_GPL(kill_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 dev_dax_range *dev_range = &dev_dax->ranges[i];
+ struct range *range = &dev_range->range;
struct dax_region *dax_region = dev_dax->region;
+ struct resource *res = &dax_region->res;
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);
- __release_region(&dax_region->res, range->start, range_len(range));
+ if (dev_range->dax_resource) {
+ res = dev_range->dax_resource->res;
+ dev_dbg(&dev_dax->dev, "Trim sparse extent %pr\n", res);
+ }
+
+ __release_region(res, range->start, range_len(range));
+
+ if (dev_range->dax_resource)
+ dev_range->dax_resource->use_cnt--;
+
if (--dev_dax->nr_range == 0) {
kfree(dev_dax->ranges);
dev_dax->ranges = NULL;
@@ -640,7 +760,7 @@ static void dax_region_unregister(void *region)
struct dax_region *alloc_dax_region(struct device *parent, int region_id,
struct range *range, int target_node, unsigned int align,
- unsigned long flags)
+ unsigned long flags, struct dax_sparse_ops *sparse_ops)
{
struct dax_region *dax_region;
@@ -658,12 +778,16 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id,
|| !IS_ALIGNED(range_len(range), align))
return NULL;
+ if (!sparse_ops && (flags & IORESOURCE_DAX_SPARSE_CAP))
+ return NULL;
+
dax_region = kzalloc(sizeof(*dax_region), GFP_KERNEL);
if (!dax_region)
return NULL;
dev_set_drvdata(parent, dax_region);
kref_init(&dax_region->kref);
+ dax_region->sparse_ops = sparse_ops;
dax_region->id = region_id;
dax_region->align = align;
dax_region->dev = parent;
@@ -845,7 +969,8 @@ static int devm_register_dax_mapping(struct dev_dax *dev_dax, int range_id)
}
static int alloc_dev_dax_range(struct resource *parent, struct dev_dax *dev_dax,
- u64 start, resource_size_t size)
+ u64 start, resource_size_t size,
+ struct dax_resource *dax_resource)
{
struct device *dev = &dev_dax->dev;
struct dev_dax_range *ranges;
@@ -884,6 +1009,7 @@ static int alloc_dev_dax_range(struct resource *parent, struct dev_dax *dev_dax,
.start = alloc->start,
.end = alloc->end,
},
+ .dax_resource = dax_resource,
};
dev_dbg(dev, "alloc range[%d]: %pa:%pa\n", dev_dax->nr_range - 1,
@@ -966,7 +1092,8 @@ static int dev_dax_shrink(struct dev_dax *dev_dax, resource_size_t size)
int i;
for (i = dev_dax->nr_range - 1; i >= 0; i--) {
- struct range *range = &dev_dax->ranges[i].range;
+ struct dev_dax_range *dev_range = &dev_dax->ranges[i];
+ struct range *range = &dev_range->range;
struct dax_mapping *mapping = dev_dax->ranges[i].mapping;
struct resource *adjust = NULL, *res;
resource_size_t shrink;
@@ -982,12 +1109,21 @@ static int dev_dax_shrink(struct dev_dax *dev_dax, resource_size_t size)
continue;
}
- for_each_dax_region_resource(dax_region, res)
- if (strcmp(res->name, dev_name(dev)) == 0
- && res->start == range->start) {
- adjust = res;
- break;
- }
+ if (dev_range->dax_resource) {
+ for_each_child_resource(dev_range->dax_resource->res, res)
+ if (strcmp(res->name, dev_name(dev)) == 0
+ && res->start == range->start) {
+ adjust = res;
+ break;
+ }
+ } else {
+ for_each_dax_region_resource(dax_region, res)
+ if (strcmp(res->name, dev_name(dev)) == 0
+ && res->start == range->start) {
+ adjust = res;
+ break;
+ }
+ }
if (dev_WARN_ONCE(dev, !adjust || i != dev_dax->nr_range - 1,
"failed to find matching resource\n"))
@@ -1025,19 +1161,21 @@ static bool adjust_ok(struct dev_dax *dev_dax, struct resource *res)
}
/**
- * dev_dax_resize_static - Expand the device into the unused portion of the
- * region. This may involve adjusting the end of an existing resource, or
- * allocating a new resource.
+ * __dev_dax_resize - Expand the device into the unused portion of the region.
+ * This may involve adjusting the end of an existing resource, or allocating a
+ * new resource.
*
* @parent: parent resource to allocate this range in
* @dev_dax: DAX device to be expanded
* @to_alloc: amount of space to alloc; must be <= space available in @parent
+ * @dax_resource: if sparse; the parent resource
*
* Return the amount of space allocated or -ERRNO on failure
*/
-static ssize_t dev_dax_resize_static(struct resource *parent,
- struct dev_dax *dev_dax,
- resource_size_t to_alloc)
+static ssize_t __dev_dax_resize(struct resource *parent,
+ struct dev_dax *dev_dax,
+ resource_size_t to_alloc,
+ struct dax_resource *dax_resource)
{
struct resource *res, *first;
int rc;
@@ -1045,7 +1183,8 @@ static ssize_t dev_dax_resize_static(struct resource *parent,
first = parent->child;
if (!first) {
rc = alloc_dev_dax_range(parent, dev_dax,
- parent->start, to_alloc);
+ parent->start, to_alloc,
+ dax_resource);
if (rc)
return rc;
return to_alloc;
@@ -1059,7 +1198,8 @@ static ssize_t dev_dax_resize_static(struct resource *parent,
if (res == first && res->start > parent->start) {
alloc = min(res->start - parent->start, to_alloc);
rc = alloc_dev_dax_range(parent, dev_dax,
- parent->start, alloc);
+ parent->start, alloc,
+ dax_resource);
if (rc)
return rc;
return alloc;
@@ -1083,7 +1223,8 @@ static ssize_t dev_dax_resize_static(struct resource *parent,
return rc;
return alloc;
}
- rc = alloc_dev_dax_range(parent, dev_dax, res->end + 1, alloc);
+ rc = alloc_dev_dax_range(parent, dev_dax, res->end + 1, alloc,
+ dax_resource);
if (rc)
return rc;
return alloc;
@@ -1094,6 +1235,51 @@ static ssize_t dev_dax_resize_static(struct resource *parent,
return 0;
}
+static ssize_t dev_dax_resize_static(struct dax_region *dax_region,
+ struct dev_dax *dev_dax,
+ resource_size_t to_alloc)
+{
+ return __dev_dax_resize(&dax_region->res, dev_dax, to_alloc, NULL);
+}
+
+static int find_free_extent(struct device *dev, void *data)
+{
+ struct dax_region *dax_region = data;
+ struct dax_resource *dax_resource;
+
+ if (!dax_region->sparse_ops->is_extent(dev))
+ return 0;
+
+ dax_resource = dev_get_drvdata(dev);
+ if (!dax_resource || !dax_avail_size(dax_resource->res))
+ return 0;
+ return 1;
+}
+
+static ssize_t dev_dax_resize_sparse(struct dax_region *dax_region,
+ struct dev_dax *dev_dax,
+ resource_size_t to_alloc)
+{
+ struct dax_resource *dax_resource;
+ ssize_t alloc;
+
+ struct device *extent_dev __free(put_device) =
+ device_find_child(dax_region->dev, dax_region,
+ find_free_extent);
+ if (!extent_dev)
+ return 0;
+
+ dax_resource = dev_get_drvdata(extent_dev);
+ if (!dax_resource)
+ return 0;
+
+ to_alloc = min(dax_avail_size(dax_resource->res), to_alloc);
+ alloc = __dev_dax_resize(dax_resource->res, dev_dax, to_alloc, dax_resource);
+ if (alloc > 0)
+ dax_resource->use_cnt++;
+ return alloc;
+}
+
static ssize_t dev_dax_resize(struct dax_region *dax_region,
struct dev_dax *dev_dax, resource_size_t size)
{
@@ -1118,7 +1304,10 @@ static ssize_t dev_dax_resize(struct dax_region *dax_region,
return -ENXIO;
retry:
- alloc = dev_dax_resize_static(&dax_region->res, dev_dax, to_alloc);
+ if (is_sparse(dax_region))
+ alloc = dev_dax_resize_sparse(dax_region, dev_dax, to_alloc);
+ else
+ alloc = dev_dax_resize_static(dax_region, dev_dax, to_alloc);
if (alloc <= 0)
return alloc;
to_alloc -= alloc;
@@ -1227,7 +1416,7 @@ static ssize_t mapping_store(struct device *dev, struct device_attribute *attr,
to_alloc = range_len(&r);
if (alloc_is_aligned(dev_dax, to_alloc))
rc = alloc_dev_dax_range(&dax_region->res, dev_dax, r.start,
- to_alloc);
+ to_alloc, NULL);
up_write(&dax_dev_rwsem);
up_write(&dax_region_rwsem);
@@ -1466,6 +1655,11 @@ static struct dev_dax *__devm_create_dev_dax(struct dev_dax_data *data)
struct device *dev;
int rc;
+ if (is_sparse(dax_region) && data->size) {
+ dev_err(parent, "Sparse DAX region devices must be created initially with 0 size");
+ return ERR_PTR(-EINVAL);
+ }
+
dev_dax = kzalloc(sizeof(*dev_dax), GFP_KERNEL);
if (!dev_dax)
return ERR_PTR(-ENOMEM);
@@ -1496,7 +1690,7 @@ static struct dev_dax *__devm_create_dev_dax(struct dev_dax_data *data)
dev_set_name(dev, "dax%d.%d", dax_region->id, dev_dax->id);
rc = alloc_dev_dax_range(&dax_region->res, dev_dax, dax_region->res.start,
- data->size);
+ data->size, NULL);
if (rc)
goto err_range;
@@ -9,6 +9,7 @@ struct dev_dax;
struct resource;
struct dax_device;
struct dax_region;
+struct dax_sparse_ops;
/* dax bus specific ioresource flags */
#define IORESOURCE_DAX_STATIC BIT(0)
@@ -17,7 +18,7 @@ struct dax_region;
struct dax_region *alloc_dax_region(struct device *parent, int region_id,
struct range *range, int target_node, unsigned int align,
- unsigned long flags);
+ unsigned long flags, struct dax_sparse_ops *sparse_ops);
struct dev_dax_data {
struct dax_region *dax_region;
@@ -5,6 +5,57 @@
#include "../cxl/cxl.h"
#include "bus.h"
+#include "dax-private.h"
+
+static int __cxl_dax_add_resource(struct dax_region *dax_region,
+ struct region_extent *region_extent)
+{
+ struct device *dev = ®ion_extent->dev;
+ resource_size_t start, length;
+
+ start = dax_region->res.start + region_extent->hpa_range.start;
+ length = range_len(®ion_extent->hpa_range);
+ return dax_region_add_resource(dax_region, dev, start, length);
+}
+
+static int cxl_dax_add_resource(struct device *dev, void *data)
+{
+ struct dax_region *dax_region = data;
+ struct region_extent *region_extent;
+
+ region_extent = to_region_extent(dev);
+ if (!region_extent)
+ return 0;
+
+ dev_dbg(dax_region->dev, "Adding resource HPA %pra\n",
+ ®ion_extent->hpa_range);
+
+ return __cxl_dax_add_resource(dax_region, region_extent);
+}
+
+static int cxl_dax_region_notify(struct device *dev,
+ struct cxl_notify_data *notify_data)
+{
+ struct cxl_dax_region *cxlr_dax = to_cxl_dax_region(dev);
+ struct dax_region *dax_region = dev_get_drvdata(dev);
+ struct region_extent *region_extent = notify_data->region_extent;
+
+ switch (notify_data->event) {
+ case DCD_ADD_CAPACITY:
+ return __cxl_dax_add_resource(dax_region, region_extent);
+ case DCD_RELEASE_CAPACITY:
+ return dax_region_rm_resource(dax_region, ®ion_extent->dev);
+ case DCD_FORCED_CAPACITY_RELEASE:
+ default:
+ dev_err(&cxlr_dax->dev, "Unknown DC event %d\n",
+ notify_data->event);
+ return -ENXIO;
+ }
+}
+
+struct dax_sparse_ops sparse_ops = {
+ .is_extent = is_region_extent,
+};
static int cxl_dax_region_probe(struct device *dev)
{
@@ -24,15 +75,18 @@ static int cxl_dax_region_probe(struct device *dev)
flags |= IORESOURCE_DAX_SPARSE_CAP;
dax_region = alloc_dax_region(dev, cxlr->id, &cxlr_dax->hpa_range, nid,
- PMD_SIZE, flags);
+ PMD_SIZE, flags, &sparse_ops);
if (!dax_region)
return -ENOMEM;
- if (cxlr->mode == CXL_REGION_DC)
+ if (cxlr->mode == CXL_REGION_DC) {
+ device_for_each_child(&cxlr_dax->dev, dax_region,
+ cxl_dax_add_resource);
/* Add empty seed dax device */
dev_size = 0;
- else
+ } else {
dev_size = range_len(&cxlr_dax->hpa_range);
+ }
data = (struct dev_dax_data) {
.dax_region = dax_region,
@@ -47,6 +101,7 @@ static int cxl_dax_region_probe(struct device *dev)
static struct cxl_driver cxl_dax_region_driver = {
.name = "cxl_dax_region",
.probe = cxl_dax_region_probe,
+ .notify = cxl_dax_region_notify,
.id = CXL_DEVICE_DAX_REGION,
.drv = {
.suppress_bind_attrs = true,
@@ -16,6 +16,14 @@ struct inode *dax_inode(struct dax_device *dax_dev);
int dax_bus_init(void);
void dax_bus_exit(void);
+/**
+ * struct dax_sparse_ops - Operations for sparse regions
+ * @is_extent: return if the device is an extent
+ */
+struct dax_sparse_ops {
+ bool (*is_extent)(struct device *dev);
+};
+
/**
* struct dax_region - mapping infrastructure for dax devices
* @id: kernel-wide unique region for a memory range
@@ -27,6 +35,7 @@ void dax_bus_exit(void);
* @res: resource tree to track instance allocations
* @seed: allow userspace to find the first unbound seed device
* @youngest: allow userspace to find the most recently created device
+ * @sparse_ops: operations required for sparse regions
*/
struct dax_region {
int id;
@@ -38,6 +47,7 @@ struct dax_region {
struct resource res;
struct device *seed;
struct device *youngest;
+ struct dax_sparse_ops *sparse_ops;
};
/**
@@ -57,11 +67,13 @@ struct dax_mapping {
* @pgoff: page offset
* @range: resource-span
* @mapping: reference to the dax_mapping for this range
+ * @dax_resource: if not NULL; dax sparse resource containing this range
*/
struct dev_dax_range {
unsigned long pgoff;
struct range range;
struct dax_mapping *mapping;
+ struct dax_resource *dax_resource;
};
/**
@@ -100,6 +112,34 @@ struct dev_dax {
*/
void run_dax(struct dax_device *dax_dev);
+/**
+ * struct dax_resource - For sparse regions; an active resource
+ * @region: dax_region this resources is in
+ * @res: resource
+ * @use_cnt: count the number of uses of this resource
+ *
+ * Changes to the dax_region and the dax_resources within it are protected by
+ * dax_region_rwsem
+ *
+ * dax_resource's are not intended to be used outside the dax layer.
+ */
+struct dax_resource {
+ struct dax_region *region;
+ struct resource *res;
+ unsigned int use_cnt;
+};
+
+/*
+ * Similar to run_dax() dax_region_{add,rm}_resource() and dax_avail_size() are
+ * exported but are not intended to be generic operations outside the dax
+ * subsystem. They are only generic between the dax layer and the dax drivers.
+ */
+int dax_region_add_resource(struct dax_region *dax_region, struct device *dev,
+ resource_size_t start, resource_size_t length);
+int dax_region_rm_resource(struct dax_region *dax_region,
+ struct device *dev);
+resource_size_t dax_avail_size(struct resource *dax_resource);
+
static inline struct dev_dax *to_dev_dax(struct device *dev)
{
return container_of(dev, struct dev_dax, dev);
@@ -28,7 +28,7 @@ static int dax_hmem_probe(struct platform_device *pdev)
mri = dev->platform_data;
dax_region = alloc_dax_region(dev, pdev->id, &mri->range,
- mri->target_node, PMD_SIZE, flags);
+ mri->target_node, PMD_SIZE, flags, NULL);
if (!dax_region)
return -ENOMEM;
@@ -54,7 +54,7 @@ static struct dev_dax *__dax_pmem_probe(struct device *dev)
range.start += offset;
dax_region = alloc_dax_region(dev, region_id, &range,
nd_region->target_node, le32_to_cpu(pfn_sb->align),
- IORESOURCE_DAX_STATIC);
+ IORESOURCE_DAX_STATIC, NULL);
if (!dax_region)
return ERR_PTR(-ENOMEM);
@@ -27,6 +27,9 @@ struct resource {
struct resource *parent, *sibling, *child;
};
+#define for_each_child_resource(parent, res) \
+ for (res = (parent)->child; res; res = res->sibling)
+
/*
* IO resources have these defined flags.
*