libnvdimm: namespace indices: read and validate
This on media label format [1] consists of two index blocks followed by
an array of labels. None of these structures are ever updated in place.
A sequence number tracks the current active index and the next one to
write, while labels are written to free slots.
+------------+
| |
| nsindex0 |
| |
+------------+
| |
| nsindex1 |
| |
+------------+
| label0 |
+------------+
| label1 |
+------------+
| |
....nslot...
| |
+------------+
| labelN |
+------------+
After reading valid labels, store the dpa ranges they claim into
per-dimm resource trees.
[1]: http://pmem.io/documents/NVDIMM_Namespace_Spec.pdf
Cc: Neil Brown <neilb@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index 0285e45..401fa0d 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -16,11 +16,15 @@
#include <linux/device.h>
#include <linux/mutex.h>
#include <linux/ndctl.h>
+#include "label.h"
struct nvdimm_drvdata {
struct device *dev;
+ int nsindex_size;
struct nd_cmd_get_config_size nsarea;
void *data;
+ int ns_current, ns_next;
+ struct resource dpa;
};
struct nd_region_namespaces {
@@ -28,6 +32,37 @@
int active;
};
+static inline struct nd_namespace_index *to_namespace_index(
+ struct nvdimm_drvdata *ndd, int i)
+{
+ if (i < 0)
+ return NULL;
+
+ return ndd->data + sizeof_namespace_index(ndd) * i;
+}
+
+static inline struct nd_namespace_index *to_current_namespace_index(
+ struct nvdimm_drvdata *ndd)
+{
+ return to_namespace_index(ndd, ndd->ns_current);
+}
+
+static inline struct nd_namespace_index *to_next_namespace_index(
+ struct nvdimm_drvdata *ndd)
+{
+ return to_namespace_index(ndd, ndd->ns_next);
+}
+
+#define nd_dbg_dpa(r, d, res, fmt, arg...) \
+ dev_dbg((r) ? &(r)->dev : (d)->dev, "%s: %.13s: %#llx @ %#llx " fmt, \
+ (r) ? dev_name((d)->dev) : "", res ? res->name : "null", \
+ (unsigned long long) (res ? resource_size(res) : 0), \
+ (unsigned long long) (res ? res->start : 0), ##arg)
+
+#define for_each_dpa_resource_safe(ndd, res, next) \
+ for (res = (ndd)->dpa.child, next = res ? res->sibling : NULL; \
+ res; res = next, next = next ? next->sibling : NULL)
+
struct nd_region {
struct device dev;
u16 ndr_mappings;
@@ -39,6 +74,15 @@
struct nd_mapping mapping[0];
};
+/*
+ * Lookup next in the repeating sequence of 01, 10, and 11.
+ */
+static inline unsigned nd_inc_seq(unsigned seq)
+{
+ static const unsigned next[] = { 0, 2, 3, 1 };
+
+ return next[seq & 3];
+}
enum nd_async_mode {
ND_SYNC,
ND_ASYNC,
@@ -58,4 +102,9 @@
void nvdimm_bus_lock(struct device *dev);
void nvdimm_bus_unlock(struct device *dev);
bool is_nvdimm_bus_locked(struct device *dev);
+int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd);
+void nvdimm_free_dpa(struct nvdimm_drvdata *ndd, struct resource *res);
+struct resource *nvdimm_allocate_dpa(struct nvdimm_drvdata *ndd,
+ struct nd_label_id *label_id, resource_size_t start,
+ resource_size_t n);
#endif /* __ND_H__ */