libnvdimm: infrastructure for btt devices
NVDIMM namespaces, in addition to accepting "struct bio" based requests,
also have the capability to perform byte-aligned accesses. By default
only the bio/block interface is used. However, if another driver can
make effective use of the byte-aligned capability it can claim namespace
interface and use the byte-aligned ->rw_bytes() interface.
The BTT driver is the initial first consumer of this mechanism to allow
adding atomic sector update semantics to a pmem or blk namespace. This
patch is the sysfs infrastructure to allow configuring a BTT instance
for a namespace. Enabling that BTT and performing i/o is in a
subsequent patch.
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
index 50b502b..2c50a07 100644
--- a/drivers/nvdimm/namespace_devs.c
+++ b/drivers/nvdimm/namespace_devs.c
@@ -102,7 +102,7 @@
} else
return -ENXIO;
- if (dev->driver)
+ if (dev->driver || to_ndns(dev)->claim)
return -EBUSY;
input = kmemdup(buf, len + 1, GFP_KERNEL);
@@ -133,7 +133,7 @@
static resource_size_t nd_namespace_blk_size(struct nd_namespace_blk *nsblk)
{
- struct nd_region *nd_region = to_nd_region(nsblk->dev.parent);
+ struct nd_region *nd_region = to_nd_region(nsblk->common.dev.parent);
struct nd_mapping *nd_mapping = &nd_region->mapping[0];
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
struct nd_label_id label_id;
@@ -152,9 +152,9 @@
static int nd_namespace_label_update(struct nd_region *nd_region,
struct device *dev)
{
- dev_WARN_ONCE(dev, dev->driver,
+ dev_WARN_ONCE(dev, dev->driver || to_ndns(dev)->claim,
"namespace must be idle during label update\n");
- if (dev->driver)
+ if (dev->driver || to_ndns(dev)->claim)
return 0;
/*
@@ -666,7 +666,7 @@
u8 *uuid = NULL;
int rc, i;
- if (dev->driver)
+ if (dev->driver || to_ndns(dev)->claim)
return -EBUSY;
if (is_namespace_pmem(dev)) {
@@ -733,12 +733,16 @@
nd_namespace_pmem_set_size(nd_region, nspm,
val * nd_region->ndr_mappings);
} else if (is_namespace_blk(dev)) {
+ struct nd_namespace_blk *nsblk = to_nd_namespace_blk(dev);
+
/*
* Try to delete the namespace if we deleted all of its
- * allocation and this is not the seed device for the
- * region.
+ * allocation, this is not the seed device for the
+ * region, and it is not actively claimed by a btt
+ * instance.
*/
- if (val == 0 && nd_region->ns_seed != dev)
+ if (val == 0 && nd_region->ns_seed != dev
+ && !nsblk->common.claim)
nd_device_unregister(dev, ND_ASYNC);
}
@@ -789,26 +793,42 @@
return rc < 0 ? rc : len;
}
-static ssize_t size_show(struct device *dev,
- struct device_attribute *attr, char *buf)
+resource_size_t __nvdimm_namespace_capacity(struct nd_namespace_common *ndns)
{
- unsigned long long size = 0;
+ struct device *dev = &ndns->dev;
- nvdimm_bus_lock(dev);
if (is_namespace_pmem(dev)) {
struct nd_namespace_pmem *nspm = to_nd_namespace_pmem(dev);
- size = resource_size(&nspm->nsio.res);
+ return resource_size(&nspm->nsio.res);
} else if (is_namespace_blk(dev)) {
- size = nd_namespace_blk_size(to_nd_namespace_blk(dev));
+ return nd_namespace_blk_size(to_nd_namespace_blk(dev));
} else if (is_namespace_io(dev)) {
struct nd_namespace_io *nsio = to_nd_namespace_io(dev);
- size = resource_size(&nsio->res);
- }
- nvdimm_bus_unlock(dev);
+ return resource_size(&nsio->res);
+ } else
+ WARN_ONCE(1, "unknown namespace type\n");
+ return 0;
+}
- return sprintf(buf, "%llu\n", size);
+resource_size_t nvdimm_namespace_capacity(struct nd_namespace_common *ndns)
+{
+ resource_size_t size;
+
+ nvdimm_bus_lock(&ndns->dev);
+ size = __nvdimm_namespace_capacity(ndns);
+ nvdimm_bus_unlock(&ndns->dev);
+
+ return size;
+}
+EXPORT_SYMBOL(nvdimm_namespace_capacity);
+
+static ssize_t size_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%llu\n", (unsigned long long)
+ nvdimm_namespace_capacity(to_ndns(dev)));
}
static DEVICE_ATTR(size, S_IRUGO, size_show, size_store);
@@ -897,8 +917,8 @@
{
struct nd_region *nd_region = to_nd_region(dev->parent);
u8 *uuid = NULL;
+ ssize_t rc = 0;
u8 **ns_uuid;
- ssize_t rc;
if (is_namespace_pmem(dev)) {
struct nd_namespace_pmem *nspm = to_nd_namespace_pmem(dev);
@@ -914,7 +934,10 @@
device_lock(dev);
nvdimm_bus_lock(dev);
wait_nvdimm_bus_probe_idle(dev);
- rc = nd_uuid_store(dev, &uuid, buf, len);
+ if (to_ndns(dev)->claim)
+ rc = -EBUSY;
+ if (rc >= 0)
+ rc = nd_uuid_store(dev, &uuid, buf, len);
if (rc >= 0)
rc = namespace_update_uuid(nd_region, dev, uuid, ns_uuid);
if (rc >= 0)
@@ -971,15 +994,18 @@
{
struct nd_namespace_blk *nsblk = to_nd_namespace_blk(dev);
struct nd_region *nd_region = to_nd_region(dev->parent);
- ssize_t rc;
+ ssize_t rc = 0;
if (!is_namespace_blk(dev))
return -ENXIO;
device_lock(dev);
nvdimm_bus_lock(dev);
- rc = nd_sector_size_store(dev, buf, &nsblk->lbasize,
- ns_lbasize_supported);
+ if (to_ndns(dev)->claim)
+ rc = -EBUSY;
+ if (rc >= 0)
+ rc = nd_sector_size_store(dev, buf, &nsblk->lbasize,
+ ns_lbasize_supported);
if (rc >= 0)
rc = nd_namespace_label_update(nd_region, dev);
dev_dbg(dev, "%s: result: %zd %s: %s%s", __func__,
@@ -1034,12 +1060,48 @@
}
static DEVICE_ATTR_RO(dpa_extents);
+static ssize_t holder_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct nd_namespace_common *ndns = to_ndns(dev);
+ ssize_t rc;
+
+ device_lock(dev);
+ rc = sprintf(buf, "%s\n", ndns->claim ? dev_name(ndns->claim) : "");
+ device_unlock(dev);
+
+ return rc;
+}
+static DEVICE_ATTR_RO(holder);
+
+static ssize_t force_raw_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t len)
+{
+ bool force_raw;
+ int rc = strtobool(buf, &force_raw);
+
+ if (rc)
+ return rc;
+
+ to_ndns(dev)->force_raw = force_raw;
+ return len;
+}
+
+static ssize_t force_raw_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%d\n", to_ndns(dev)->force_raw);
+}
+static DEVICE_ATTR_RW(force_raw);
+
static struct attribute *nd_namespace_attributes[] = {
&dev_attr_nstype.attr,
&dev_attr_size.attr,
&dev_attr_uuid.attr,
+ &dev_attr_holder.attr,
&dev_attr_resource.attr,
&dev_attr_alt_name.attr,
+ &dev_attr_force_raw.attr,
&dev_attr_sector_size.attr,
&dev_attr_dpa_extents.attr,
NULL,
@@ -1066,7 +1128,9 @@
return a->mode;
}
- if (a == &dev_attr_nstype.attr || a == &dev_attr_size.attr)
+ if (a == &dev_attr_nstype.attr || a == &dev_attr_size.attr
+ || a == &dev_attr_holder.attr
+ || a == &dev_attr_force_raw.attr)
return a->mode;
return 0;
@@ -1083,6 +1147,66 @@
NULL,
};
+struct nd_namespace_common *nvdimm_namespace_common_probe(struct device *dev)
+{
+ struct nd_btt *nd_btt = is_nd_btt(dev) ? to_nd_btt(dev) : NULL;
+ struct nd_namespace_common *ndns;
+ resource_size_t size;
+
+ if (nd_btt) {
+ ndns = nd_btt->ndns;
+ if (!ndns)
+ return ERR_PTR(-ENODEV);
+
+ /*
+ * Flush any in-progess probes / removals in the driver
+ * for the raw personality of this namespace.
+ */
+ device_lock(&ndns->dev);
+ device_unlock(&ndns->dev);
+ if (ndns->dev.driver) {
+ dev_dbg(&ndns->dev, "is active, can't bind %s\n",
+ dev_name(&nd_btt->dev));
+ return ERR_PTR(-EBUSY);
+ }
+ if (dev_WARN_ONCE(&ndns->dev, ndns->claim != &nd_btt->dev,
+ "host (%s) vs claim (%s) mismatch\n",
+ dev_name(&nd_btt->dev),
+ dev_name(ndns->claim)))
+ return ERR_PTR(-ENXIO);
+ } else {
+ ndns = to_ndns(dev);
+ if (ndns->claim) {
+ dev_dbg(dev, "claimed by %s, failing probe\n",
+ dev_name(ndns->claim));
+
+ return ERR_PTR(-ENXIO);
+ }
+ }
+
+ size = nvdimm_namespace_capacity(ndns);
+ if (size < ND_MIN_NAMESPACE_SIZE) {
+ dev_dbg(&ndns->dev, "%pa, too small must be at least %#x\n",
+ &size, ND_MIN_NAMESPACE_SIZE);
+ return ERR_PTR(-ENODEV);
+ }
+
+ if (is_namespace_pmem(&ndns->dev)) {
+ struct nd_namespace_pmem *nspm;
+
+ nspm = to_nd_namespace_pmem(&ndns->dev);
+ if (!nspm->uuid) {
+ dev_dbg(&ndns->dev, "%s: uuid not set\n", __func__);
+ return ERR_PTR(-ENODEV);
+ }
+ } else if (is_namespace_blk(&ndns->dev)) {
+ return ERR_PTR(-ENODEV); /* TODO */
+ }
+
+ return ndns;
+}
+EXPORT_SYMBOL(nvdimm_namespace_common_probe);
+
static struct device **create_namespace_io(struct nd_region *nd_region)
{
struct nd_namespace_io *nsio;
@@ -1099,7 +1223,7 @@
return NULL;
}
- dev = &nsio->dev;
+ dev = &nsio->common.dev;
dev->type = &namespace_io_device_type;
dev->parent = &nd_region->dev;
res = &nsio->res;
@@ -1313,7 +1437,7 @@
if (!nspm)
return NULL;
- dev = &nspm->nsio.dev;
+ dev = &nspm->nsio.common.dev;
dev->type = &namespace_pmem_device_type;
dev->parent = &nd_region->dev;
res = &nspm->nsio.res;
@@ -1346,7 +1470,7 @@
return devs;
err:
- namespace_pmem_release(&nspm->nsio.dev);
+ namespace_pmem_release(&nspm->nsio.common.dev);
return NULL;
}
@@ -1385,7 +1509,7 @@
if (!nsblk)
return NULL;
- dev = &nsblk->dev;
+ dev = &nsblk->common.dev;
dev->type = &namespace_blk_device_type;
nsblk->id = ida_simple_get(&nd_region->ns_ida, 0, 0, GFP_KERNEL);
if (nsblk->id < 0) {
@@ -1396,7 +1520,7 @@
dev->parent = &nd_region->dev;
dev->groups = nd_namespace_attribute_groups;
- return &nsblk->dev;
+ return &nsblk->common.dev;
}
void nd_region_create_blk_seed(struct nd_region *nd_region)
@@ -1413,6 +1537,18 @@
nd_device_register(nd_region->ns_seed);
}
+void nd_region_create_btt_seed(struct nd_region *nd_region)
+{
+ WARN_ON(!is_nvdimm_bus_locked(&nd_region->dev));
+ nd_region->btt_seed = nd_btt_create(nd_region);
+ /*
+ * Seed creation failures are not fatal, provisioning is simply
+ * disabled until memory becomes available
+ */
+ if (!nd_region->btt_seed)
+ dev_err(&nd_region->dev, "failed to create btt namespace\n");
+}
+
static struct device **create_namespace_blk(struct nd_region *nd_region)
{
struct nd_mapping *nd_mapping = &nd_region->mapping[0];
@@ -1446,7 +1582,7 @@
if (!res)
goto err;
nd_dbg_dpa(nd_region, ndd, res, "%s assign\n",
- dev_name(&nsblk->dev));
+ dev_name(&nsblk->common.dev));
break;
}
}
@@ -1462,7 +1598,7 @@
nsblk = kzalloc(sizeof(*nsblk), GFP_KERNEL);
if (!nsblk)
goto err;
- dev = &nsblk->dev;
+ dev = &nsblk->common.dev;
dev->type = &namespace_blk_device_type;
dev->parent = &nd_region->dev;
dev_set_name(dev, "namespace%d.%d", nd_region->id, count);
@@ -1482,7 +1618,7 @@
if (!res)
goto err;
nd_dbg_dpa(nd_region, ndd, res, "%s assign\n",
- dev_name(&nsblk->dev));
+ dev_name(&nsblk->common.dev));
}
dev_dbg(&nd_region->dev, "%s: discovered %d blk namespace%s\n",
@@ -1503,7 +1639,7 @@
nsblk = kzalloc(sizeof(*nsblk), GFP_KERNEL);
if (!nsblk)
goto err;
- dev = &nsblk->dev;
+ dev = &nsblk->common.dev;
dev->type = &namespace_blk_device_type;
dev->parent = &nd_region->dev;
devs[count++] = dev;
@@ -1514,7 +1650,7 @@
err:
for (i = 0; i < count; i++) {
nsblk = to_nd_namespace_blk(devs[i]);
- namespace_blk_release(&nsblk->dev);
+ namespace_blk_release(&nsblk->common.dev);
}
kfree(devs);
return NULL;