libnvdimm: blk labels and namespace instantiation

A blk label set describes a namespace comprised of one or more
discontiguous dpa ranges on a single dimm.  They may alias with one or
more pmem interleave sets that include the given dimm.

This is the runtime/volatile configuration infrastructure for sysfs
manipulation of 'alt_name', 'uuid', 'size', and 'sector_size'.  A later
patch will make these settings persistent by writing back the label(s).

Unlike pmem namespaces, multiple blk namespaces can be created per
region.  Once a blk namespace has been created a new seed device
(unconfigured child of a parent blk region) is instantiated.  As long as
a region has 'available_size' != 0 new child namespaces may be created.

Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 40 insertions, 0 deletions

diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c
index cf99cce8ef33..dd824d7c2669 100644
--- a/drivers/nvdimm/core.c
+++ b/drivers/nvdimm/core.c
@@ -173,6 +173,46 @@ int nd_uuid_store(struct device *dev, u8 **uuid_out, const char *buf,
         return 0;
 }
 
+ssize_t nd_sector_size_show(unsigned long current_lbasize,
+                const unsigned long *supported, char *buf)
+{
+        ssize_t len = 0;
+        int i;
+
+        for (i = 0; supported[i]; i++)
+                if (current_lbasize == supported[i])
+                        len += sprintf(buf + len, "[%ld] ", supported[i]);
+                else
+                        len += sprintf(buf + len, "%ld ", supported[i]);
+        len += sprintf(buf + len, "\n");
+        return len;
+}
+
+ssize_t nd_sector_size_store(struct device *dev, const char *buf,
+                unsigned long *current_lbasize, const unsigned long *supported)
+{
+        unsigned long lbasize;
+        int rc, i;
+
+        if (dev->driver)
+                return -EBUSY;
+
+        rc = kstrtoul(buf, 0, &lbasize);
+        if (rc)
+                return rc;
+
+        for (i = 0; supported[i]; i++)
+                if (lbasize == supported[i])
+                        break;
+
+        if (supported[i]) {
+                *current_lbasize = lbasize;
+                return 0;
+        } else {
+                return -EINVAL;
+        }
+}
+
 static ssize_t commands_show(struct device *dev,
                 struct device_attribute *attr, char *buf)
 {