These changes are the raw update to linux-4.4.6-rt14. Kernel sources
[kvmfornfv.git] / kernel / drivers / nvdimm / pfn_devs.c
diff --git a/kernel/drivers/nvdimm/pfn_devs.c b/kernel/drivers/nvdimm/pfn_devs.c
new file mode 100644 (file)
index 0000000..71805a1
--- /dev/null
@@ -0,0 +1,337 @@
+/*
+ * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+#include <linux/blkdev.h>
+#include <linux/device.h>
+#include <linux/genhd.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include "nd-core.h"
+#include "pfn.h"
+#include "nd.h"
+
+static void nd_pfn_release(struct device *dev)
+{
+       struct nd_region *nd_region = to_nd_region(dev->parent);
+       struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+
+       dev_dbg(dev, "%s\n", __func__);
+       nd_detach_ndns(&nd_pfn->dev, &nd_pfn->ndns);
+       ida_simple_remove(&nd_region->pfn_ida, nd_pfn->id);
+       kfree(nd_pfn->uuid);
+       kfree(nd_pfn);
+}
+
+static struct device_type nd_pfn_device_type = {
+       .name = "nd_pfn",
+       .release = nd_pfn_release,
+};
+
+bool is_nd_pfn(struct device *dev)
+{
+       return dev ? dev->type == &nd_pfn_device_type : false;
+}
+EXPORT_SYMBOL(is_nd_pfn);
+
+struct nd_pfn *to_nd_pfn(struct device *dev)
+{
+       struct nd_pfn *nd_pfn = container_of(dev, struct nd_pfn, dev);
+
+       WARN_ON(!is_nd_pfn(dev));
+       return nd_pfn;
+}
+EXPORT_SYMBOL(to_nd_pfn);
+
+static ssize_t mode_show(struct device *dev,
+               struct device_attribute *attr, char *buf)
+{
+       struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+
+       switch (nd_pfn->mode) {
+       case PFN_MODE_RAM:
+               return sprintf(buf, "ram\n");
+       case PFN_MODE_PMEM:
+               return sprintf(buf, "pmem\n");
+       default:
+               return sprintf(buf, "none\n");
+       }
+}
+
+static ssize_t mode_store(struct device *dev,
+               struct device_attribute *attr, const char *buf, size_t len)
+{
+       struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+       ssize_t rc = 0;
+
+       device_lock(dev);
+       nvdimm_bus_lock(dev);
+       if (dev->driver)
+               rc = -EBUSY;
+       else {
+               size_t n = len - 1;
+
+               if (strncmp(buf, "pmem\n", n) == 0
+                               || strncmp(buf, "pmem", n) == 0) {
+                       /* TODO: allocate from PMEM support */
+                       rc = -ENOTTY;
+               } else if (strncmp(buf, "ram\n", n) == 0
+                               || strncmp(buf, "ram", n) == 0)
+                       nd_pfn->mode = PFN_MODE_RAM;
+               else if (strncmp(buf, "none\n", n) == 0
+                               || strncmp(buf, "none", n) == 0)
+                       nd_pfn->mode = PFN_MODE_NONE;
+               else
+                       rc = -EINVAL;
+       }
+       dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__,
+                       rc, buf, buf[len - 1] == '\n' ? "" : "\n");
+       nvdimm_bus_unlock(dev);
+       device_unlock(dev);
+
+       return rc ? rc : len;
+}
+static DEVICE_ATTR_RW(mode);
+
+static ssize_t uuid_show(struct device *dev,
+               struct device_attribute *attr, char *buf)
+{
+       struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+
+       if (nd_pfn->uuid)
+               return sprintf(buf, "%pUb\n", nd_pfn->uuid);
+       return sprintf(buf, "\n");
+}
+
+static ssize_t uuid_store(struct device *dev,
+               struct device_attribute *attr, const char *buf, size_t len)
+{
+       struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+       ssize_t rc;
+
+       device_lock(dev);
+       rc = nd_uuid_store(dev, &nd_pfn->uuid, buf, len);
+       dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__,
+                       rc, buf, buf[len - 1] == '\n' ? "" : "\n");
+       device_unlock(dev);
+
+       return rc ? rc : len;
+}
+static DEVICE_ATTR_RW(uuid);
+
+static ssize_t namespace_show(struct device *dev,
+               struct device_attribute *attr, char *buf)
+{
+       struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+       ssize_t rc;
+
+       nvdimm_bus_lock(dev);
+       rc = sprintf(buf, "%s\n", nd_pfn->ndns
+                       ? dev_name(&nd_pfn->ndns->dev) : "");
+       nvdimm_bus_unlock(dev);
+       return rc;
+}
+
+static ssize_t namespace_store(struct device *dev,
+               struct device_attribute *attr, const char *buf, size_t len)
+{
+       struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+       ssize_t rc;
+
+       device_lock(dev);
+       nvdimm_bus_lock(dev);
+       rc = nd_namespace_store(dev, &nd_pfn->ndns, buf, len);
+       dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__,
+                       rc, buf, buf[len - 1] == '\n' ? "" : "\n");
+       nvdimm_bus_unlock(dev);
+       device_unlock(dev);
+
+       return rc;
+}
+static DEVICE_ATTR_RW(namespace);
+
+static struct attribute *nd_pfn_attributes[] = {
+       &dev_attr_mode.attr,
+       &dev_attr_namespace.attr,
+       &dev_attr_uuid.attr,
+       NULL,
+};
+
+static struct attribute_group nd_pfn_attribute_group = {
+       .attrs = nd_pfn_attributes,
+};
+
+static const struct attribute_group *nd_pfn_attribute_groups[] = {
+       &nd_pfn_attribute_group,
+       &nd_device_attribute_group,
+       &nd_numa_attribute_group,
+       NULL,
+};
+
+static struct device *__nd_pfn_create(struct nd_region *nd_region,
+               u8 *uuid, enum nd_pfn_mode mode,
+               struct nd_namespace_common *ndns)
+{
+       struct nd_pfn *nd_pfn;
+       struct device *dev;
+
+       /* we can only create pages for contiguous ranged of pmem */
+       if (!is_nd_pmem(&nd_region->dev))
+               return NULL;
+
+       nd_pfn = kzalloc(sizeof(*nd_pfn), GFP_KERNEL);
+       if (!nd_pfn)
+               return NULL;
+
+       nd_pfn->id = ida_simple_get(&nd_region->pfn_ida, 0, 0, GFP_KERNEL);
+       if (nd_pfn->id < 0) {
+               kfree(nd_pfn);
+               return NULL;
+       }
+
+       nd_pfn->mode = mode;
+       if (uuid)
+               uuid = kmemdup(uuid, 16, GFP_KERNEL);
+       nd_pfn->uuid = uuid;
+       dev = &nd_pfn->dev;
+       dev_set_name(dev, "pfn%d.%d", nd_region->id, nd_pfn->id);
+       dev->parent = &nd_region->dev;
+       dev->type = &nd_pfn_device_type;
+       dev->groups = nd_pfn_attribute_groups;
+       device_initialize(&nd_pfn->dev);
+       if (ndns && !__nd_attach_ndns(&nd_pfn->dev, ndns, &nd_pfn->ndns)) {
+               dev_dbg(&ndns->dev, "%s failed, already claimed by %s\n",
+                               __func__, dev_name(ndns->claim));
+               put_device(dev);
+               return NULL;
+       }
+       return dev;
+}
+
+struct device *nd_pfn_create(struct nd_region *nd_region)
+{
+       struct device *dev = __nd_pfn_create(nd_region, NULL, PFN_MODE_NONE,
+                       NULL);
+
+       if (dev)
+               __nd_device_register(dev);
+       return dev;
+}
+
+int nd_pfn_validate(struct nd_pfn *nd_pfn)
+{
+       struct nd_namespace_common *ndns = nd_pfn->ndns;
+       struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
+       struct nd_namespace_io *nsio;
+       u64 checksum, offset;
+
+       if (!pfn_sb || !ndns)
+               return -ENODEV;
+
+       if (!is_nd_pmem(nd_pfn->dev.parent))
+               return -ENODEV;
+
+       /* section alignment for simple hotplug */
+       if (nvdimm_namespace_capacity(ndns) < ND_PFN_ALIGN)
+               return -ENODEV;
+
+       if (nvdimm_read_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb)))
+               return -ENXIO;
+
+       if (memcmp(pfn_sb->signature, PFN_SIG, PFN_SIG_LEN) != 0)
+               return -ENODEV;
+
+       checksum = le64_to_cpu(pfn_sb->checksum);
+       pfn_sb->checksum = 0;
+       if (checksum != nd_sb_checksum((struct nd_gen_sb *) pfn_sb))
+               return -ENODEV;
+       pfn_sb->checksum = cpu_to_le64(checksum);
+
+       switch (le32_to_cpu(pfn_sb->mode)) {
+       case PFN_MODE_RAM:
+               break;
+       case PFN_MODE_PMEM:
+               /* TODO: allocate from PMEM support */
+               return -ENOTTY;
+       default:
+               return -ENXIO;
+       }
+
+       if (!nd_pfn->uuid) {
+               /* from probe we allocate */
+               nd_pfn->uuid = kmemdup(pfn_sb->uuid, 16, GFP_KERNEL);
+               if (!nd_pfn->uuid)
+                       return -ENOMEM;
+       } else {
+               /* from init we validate */
+               if (memcmp(nd_pfn->uuid, pfn_sb->uuid, 16) != 0)
+                       return -EINVAL;
+       }
+
+       /*
+        * These warnings are verbose because they can only trigger in
+        * the case where the physical address alignment of the
+        * namespace has changed since the pfn superblock was
+        * established.
+        */
+       offset = le64_to_cpu(pfn_sb->dataoff);
+       nsio = to_nd_namespace_io(&ndns->dev);
+       if (nsio->res.start & ND_PFN_MASK) {
+               dev_err(&nd_pfn->dev,
+                               "init failed: %s not section aligned\n",
+                               dev_name(&ndns->dev));
+               return -EBUSY;
+       } else if (offset >= resource_size(&nsio->res)) {
+               dev_err(&nd_pfn->dev, "pfn array size exceeds capacity of %s\n",
+                               dev_name(&ndns->dev));
+               return -EBUSY;
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL(nd_pfn_validate);
+
+int nd_pfn_probe(struct nd_namespace_common *ndns, void *drvdata)
+{
+       int rc;
+       struct device *dev;
+       struct nd_pfn *nd_pfn;
+       struct nd_pfn_sb *pfn_sb;
+       struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
+
+       if (ndns->force_raw)
+               return -ENODEV;
+
+       nvdimm_bus_lock(&ndns->dev);
+       dev = __nd_pfn_create(nd_region, NULL, PFN_MODE_NONE, ndns);
+       nvdimm_bus_unlock(&ndns->dev);
+       if (!dev)
+               return -ENOMEM;
+       dev_set_drvdata(dev, drvdata);
+       pfn_sb = kzalloc(sizeof(*pfn_sb), GFP_KERNEL);
+       nd_pfn = to_nd_pfn(dev);
+       nd_pfn->pfn_sb = pfn_sb;
+       rc = nd_pfn_validate(nd_pfn);
+       nd_pfn->pfn_sb = NULL;
+       kfree(pfn_sb);
+       dev_dbg(&ndns->dev, "%s: pfn: %s\n", __func__,
+                       rc == 0 ? dev_name(dev) : "<none>");
+       if (rc < 0) {
+               __nd_detach_ndns(dev, &nd_pfn->ndns);
+               put_device(dev);
+       } else
+               __nd_device_register(&nd_pfn->dev);
+
+       return rc;
+}
+EXPORT_SYMBOL(nd_pfn_probe);