Merge branch 'for-4.7/dax' into libnvdimm-for-next

1 files changed, 272 insertions, 47 deletions

diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c
index e071e214feba..2248056d29e7 100644
--- a/drivers/nvdimm/pfn_devs.c
+++ b/drivers/nvdimm/pfn_devs.c
@@ -1,5 +1,5 @@
 /*
- * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
+ * Copyright(c) 2013-2016 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
@@ -10,6 +10,7 @@
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License for more details.
  */
+#include <linux/memremap.h>
 #include <linux/blkdev.h>
 #include <linux/device.h>
 #include <linux/genhd.h>
@@ -53,10 +54,29 @@ struct nd_pfn *to_nd_pfn(struct device *dev)
 }
 EXPORT_SYMBOL(to_nd_pfn);
 
+static struct nd_pfn *to_nd_pfn_safe(struct device *dev)
+{
+	/*
+	 * pfn device attributes are re-used by dax device instances, so we
+	 * need to be careful to correct device-to-nd_pfn conversion.
+	 */
+	if (is_nd_pfn(dev))
+		return to_nd_pfn(dev);
+
+	if (is_nd_dax(dev)) {
+		struct nd_dax *nd_dax = to_nd_dax(dev);
+
+		return &nd_dax->nd_pfn;
+	}
+
+	WARN_ON(1);
+	return NULL;
+}
+
 static ssize_t mode_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
-	struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+	struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
 
 	switch (nd_pfn->mode) {
 	case PFN_MODE_RAM:
@@ -71,7 +91,7 @@ static ssize_t mode_show(struct device *dev,
 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);
+	struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
 	ssize_t rc = 0;
 
 	device_lock(dev);
@@ -105,7 +125,7 @@ static DEVICE_ATTR_RW(mode);
 static ssize_t align_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
-	struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+	struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
 
 	return sprintf(buf, "%lx\n", nd_pfn->align);
 }
@@ -133,7 +153,7 @@ static ssize_t __align_store(struct nd_pfn *nd_pfn, const char *buf)
 static ssize_t align_store(struct device *dev,
 		struct device_attribute *attr, const char *buf, size_t len)
 {
-	struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+	struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
 	ssize_t rc;
 
 	device_lock(dev);
@@ -151,7 +171,7 @@ static DEVICE_ATTR_RW(align);
 static ssize_t uuid_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
-	struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+	struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
 
 	if (nd_pfn->uuid)
 		return sprintf(buf, "%pUb\n", nd_pfn->uuid);
@@ -161,7 +181,7 @@ static ssize_t uuid_show(struct device *dev,
 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);
+	struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
 	ssize_t rc;
 
 	device_lock(dev);
@@ -177,7 +197,7 @@ 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);
+	struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
 	ssize_t rc;
 
 	nvdimm_bus_lock(dev);
@@ -190,7 +210,7 @@ static ssize_t namespace_show(struct device *dev,
 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);
+	struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
 	ssize_t rc;
 
 	device_lock(dev);
@@ -208,7 +228,7 @@ static DEVICE_ATTR_RW(namespace);
 static ssize_t resource_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
-	struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+	struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
 	ssize_t rc;
 
 	device_lock(dev);
@@ -234,7 +254,7 @@ static DEVICE_ATTR_RO(resource);
 static ssize_t size_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
-	struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+	struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
 	ssize_t rc;
 
 	device_lock(dev);
@@ -269,7 +289,7 @@ static struct attribute *nd_pfn_attributes[] = {
 	NULL,
 };
 
-static struct attribute_group nd_pfn_attribute_group = {
+struct attribute_group nd_pfn_attribute_group = {
 	.attrs = nd_pfn_attributes,
 };
 
@@ -280,16 +300,32 @@ static const struct attribute_group *nd_pfn_attribute_groups[] = {
 	NULL,
 };
 
-static struct device *__nd_pfn_create(struct nd_region *nd_region,
+struct device *nd_pfn_devinit(struct nd_pfn *nd_pfn,
 		struct nd_namespace_common *ndns)
 {
-	struct nd_pfn *nd_pfn;
-	struct device *dev;
+	struct device *dev = &nd_pfn->dev;
 
-	/* we can only create pages for contiguous ranged of pmem */
-	if (!is_nd_pmem(&nd_region->dev))
+	if (!nd_pfn)
 		return NULL;
 
+	nd_pfn->mode = PFN_MODE_NONE;
+	nd_pfn->align = HPAGE_SIZE;
+	dev = &nd_pfn->dev;
+	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;
+}
+
+static struct nd_pfn *nd_pfn_alloc(struct nd_region *nd_region)
+{
+	struct nd_pfn *nd_pfn;
+	struct device *dev;
+
 	nd_pfn = kzalloc(sizeof(*nd_pfn), GFP_KERNEL);
 	if (!nd_pfn)
 		return NULL;
@@ -300,29 +336,27 @@ static struct device *__nd_pfn_create(struct nd_region *nd_region,
 		return NULL;
 	}
 
-	nd_pfn->mode = PFN_MODE_NONE;
-	nd_pfn->align = HPAGE_SIZE;
 	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;
+	dev->type = &nd_pfn_device_type;
+	dev->parent = &nd_region->dev;
+
+	return nd_pfn;
 }
 
 struct device *nd_pfn_create(struct nd_region *nd_region)
 {
-	struct device *dev = __nd_pfn_create(nd_region, NULL);
+	struct nd_pfn *nd_pfn;
+	struct device *dev;
+
+	if (!is_nd_pmem(&nd_region->dev))
+		return NULL;
 
-	if (dev)
-		__nd_device_register(dev);
+	nd_pfn = nd_pfn_alloc(nd_region);
+	dev = nd_pfn_devinit(nd_pfn, NULL);
+
+	__nd_device_register(dev);
 	return dev;
 }
 
@@ -360,6 +394,9 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn)
 		pfn_sb->end_trunc = 0;
 	}
 
+	if (__le16_to_cpu(pfn_sb->version_minor) < 2)
+		pfn_sb->align = 0;
+
 	switch (le32_to_cpu(pfn_sb->mode)) {
 	case PFN_MODE_RAM:
 	case PFN_MODE_PMEM:
@@ -399,7 +436,7 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn)
 		return -EBUSY;
 	}
 
-	nd_pfn->align = 1UL << ilog2(offset);
+	nd_pfn->align = le32_to_cpu(pfn_sb->align);
 	if (!is_power_of_2(offset) || offset < PAGE_SIZE) {
 		dev_err(&nd_pfn->dev, "bad offset: %#llx dax disabled\n",
 				offset);
@@ -410,11 +447,11 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn)
 }
 EXPORT_SYMBOL(nd_pfn_validate);
 
-int nd_pfn_probe(struct nd_namespace_common *ndns, void *drvdata)
+int nd_pfn_probe(struct device *dev, struct nd_namespace_common *ndns)
 {
 	int rc;
-	struct device *dev;
 	struct nd_pfn *nd_pfn;
+	struct device *pfn_dev;
 	struct nd_pfn_sb *pfn_sb;
 	struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
 
@@ -422,25 +459,213 @@ int nd_pfn_probe(struct nd_namespace_common *ndns, void *drvdata)
 		return -ENODEV;
 
 	nvdimm_bus_lock(&ndns->dev);
-	dev = __nd_pfn_create(nd_region, ndns);
+	nd_pfn = nd_pfn_alloc(nd_region);
+	pfn_dev = nd_pfn_devinit(nd_pfn, ndns);
 	nvdimm_bus_unlock(&ndns->dev);
-	if (!dev)
+	if (!pfn_dev)
 		return -ENOMEM;
-	dev_set_drvdata(dev, drvdata);
-	pfn_sb = kzalloc(sizeof(*pfn_sb), GFP_KERNEL);
-	nd_pfn = to_nd_pfn(dev);
+	pfn_sb = devm_kzalloc(dev, sizeof(*pfn_sb), GFP_KERNEL);
+	nd_pfn = to_nd_pfn(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>");
+	dev_dbg(dev, "%s: pfn: %s\n", __func__,
+			rc == 0 ? dev_name(pfn_dev) : "<none>");
 	if (rc < 0) {
-		__nd_detach_ndns(dev, &nd_pfn->ndns);
-		put_device(dev);
+		__nd_detach_ndns(pfn_dev, &nd_pfn->ndns);
+		put_device(pfn_dev);
 	} else
-		__nd_device_register(&nd_pfn->dev);
+		__nd_device_register(pfn_dev);
 
 	return rc;
 }
 EXPORT_SYMBOL(nd_pfn_probe);
+
+/*
+ * We hotplug memory at section granularity, pad the reserved area from
+ * the previous section base to the namespace base address.
+ */
+static unsigned long init_altmap_base(resource_size_t base)
+{
+	unsigned long base_pfn = PHYS_PFN(base);
+
+	return PFN_SECTION_ALIGN_DOWN(base_pfn);
+}
+
+static unsigned long init_altmap_reserve(resource_size_t base)
+{
+	unsigned long reserve = PHYS_PFN(SZ_8K);
+	unsigned long base_pfn = PHYS_PFN(base);
+
+	reserve += base_pfn - PFN_SECTION_ALIGN_DOWN(base_pfn);
+	return reserve;
+}
+
+static struct vmem_altmap *__nvdimm_setup_pfn(struct nd_pfn *nd_pfn,
+		struct resource *res, struct vmem_altmap *altmap)
+{
+	struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
+	u64 offset = le64_to_cpu(pfn_sb->dataoff);
+	u32 start_pad = __le32_to_cpu(pfn_sb->start_pad);
+	u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
+	struct nd_namespace_common *ndns = nd_pfn->ndns;
+	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
+	resource_size_t base = nsio->res.start + start_pad;
+	struct vmem_altmap __altmap = {
+		.base_pfn = init_altmap_base(base),
+		.reserve = init_altmap_reserve(base),
+	};
+
+	memcpy(res, &nsio->res, sizeof(*res));
+	res->start += start_pad;
+	res->end -= end_trunc;
+
+	nd_pfn->mode = le32_to_cpu(nd_pfn->pfn_sb->mode);
+	if (nd_pfn->mode == PFN_MODE_RAM) {
+		if (offset < SZ_8K)
+			return ERR_PTR(-EINVAL);
+		nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns);
+		altmap = NULL;
+	} else if (nd_pfn->mode == PFN_MODE_PMEM) {
+		nd_pfn->npfns = (resource_size(res) - offset) / PAGE_SIZE;
+		if (le64_to_cpu(nd_pfn->pfn_sb->npfns) > nd_pfn->npfns)
+			dev_info(&nd_pfn->dev,
+					"number of pfns truncated from %lld to %ld\n",
+					le64_to_cpu(nd_pfn->pfn_sb->npfns),
+					nd_pfn->npfns);
+		memcpy(altmap, &__altmap, sizeof(*altmap));
+		altmap->free = PHYS_PFN(offset - SZ_8K);
+		altmap->alloc = 0;
+	} else
+		return ERR_PTR(-ENXIO);
+
+	return altmap;
+}
+
+static int nd_pfn_init(struct nd_pfn *nd_pfn)
+{
+	u32 dax_label_reserve = is_nd_dax(&nd_pfn->dev) ? SZ_128K : 0;
+	struct nd_namespace_common *ndns = nd_pfn->ndns;
+	u32 start_pad = 0, end_trunc = 0;
+	resource_size_t start, size;
+	struct nd_namespace_io *nsio;
+	struct nd_region *nd_region;
+	struct nd_pfn_sb *pfn_sb;
+	unsigned long npfns;
+	phys_addr_t offset;
+	u64 checksum;
+	int rc;
+
+	pfn_sb = devm_kzalloc(&nd_pfn->dev, sizeof(*pfn_sb), GFP_KERNEL);
+	if (!pfn_sb)
+		return -ENOMEM;
+
+	nd_pfn->pfn_sb = pfn_sb;
+	rc = nd_pfn_validate(nd_pfn);
+	if (rc != -ENODEV)
+		return rc;
+
+	/* no info block, do init */;
+	nd_region = to_nd_region(nd_pfn->dev.parent);
+	if (nd_region->ro) {
+		dev_info(&nd_pfn->dev,
+				"%s is read-only, unable to init metadata\n",
+				dev_name(&nd_region->dev));
+		return -ENXIO;
+	}
+
+	memset(pfn_sb, 0, sizeof(*pfn_sb));
+
+	/*
+	 * Check if pmem collides with 'System RAM' when section aligned and
+	 * trim it accordingly
+	 */
+	nsio = to_nd_namespace_io(&ndns->dev);
+	start = PHYS_SECTION_ALIGN_DOWN(nsio->res.start);
+	size = resource_size(&nsio->res);
+	if (region_intersects(start, size, IORESOURCE_SYSTEM_RAM,
+				IORES_DESC_NONE) == REGION_MIXED) {
+		start = nsio->res.start;
+		start_pad = PHYS_SECTION_ALIGN_UP(start) - start;
+	}
+
+	start = nsio->res.start;
+	size = PHYS_SECTION_ALIGN_UP(start + size) - start;
+	if (region_intersects(start, size, IORESOURCE_SYSTEM_RAM,
+				IORES_DESC_NONE) == REGION_MIXED) {
+		size = resource_size(&nsio->res);
+		end_trunc = start + size - PHYS_SECTION_ALIGN_DOWN(start + size);
+	}
+
+	if (start_pad + end_trunc)
+		dev_info(&nd_pfn->dev, "%s section collision, truncate %d bytes\n",
+				dev_name(&ndns->dev), start_pad + end_trunc);
+
+	/*
+	 * Note, we use 64 here for the standard size of struct page,
+	 * debugging options may cause it to be larger in which case the
+	 * implementation will limit the pfns advertised through
+	 * ->direct_access() to those that are included in the memmap.
+	 */
+	start += start_pad;
+	size = resource_size(&nsio->res);
+	npfns = (size - start_pad - end_trunc - SZ_8K) / SZ_4K;
+	if (nd_pfn->mode == PFN_MODE_PMEM) {
+		unsigned long memmap_size;
+
+		/*
+		 * vmemmap_populate_hugepages() allocates the memmap array in
+		 * HPAGE_SIZE chunks.
+		 */
+		memmap_size = ALIGN(64 * npfns, HPAGE_SIZE);
+		offset = ALIGN(start + SZ_8K + memmap_size + dax_label_reserve,
+				nd_pfn->align) - start;
+	} else if (nd_pfn->mode == PFN_MODE_RAM)
+		offset = ALIGN(start + SZ_8K + dax_label_reserve,
+				nd_pfn->align) - start;
+	else
+		return -ENXIO;
+
+	if (offset + start_pad + end_trunc >= size) {
+		dev_err(&nd_pfn->dev, "%s unable to satisfy requested alignment\n",
+				dev_name(&ndns->dev));
+		return -ENXIO;
+	}
+
+	npfns = (size - offset - start_pad - end_trunc) / SZ_4K;
+	pfn_sb->mode = cpu_to_le32(nd_pfn->mode);
+	pfn_sb->dataoff = cpu_to_le64(offset);
+	pfn_sb->npfns = cpu_to_le64(npfns);
+	memcpy(pfn_sb->signature, PFN_SIG, PFN_SIG_LEN);
+	memcpy(pfn_sb->uuid, nd_pfn->uuid, 16);
+	memcpy(pfn_sb->parent_uuid, nd_dev_to_uuid(&ndns->dev), 16);
+	pfn_sb->version_major = cpu_to_le16(1);
+	pfn_sb->version_minor = cpu_to_le16(2);
+	pfn_sb->start_pad = cpu_to_le32(start_pad);
+	pfn_sb->end_trunc = cpu_to_le32(end_trunc);
+	pfn_sb->align = cpu_to_le32(nd_pfn->align);
+	checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb);
+	pfn_sb->checksum = cpu_to_le64(checksum);
+
+	return nvdimm_write_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb));
+}
+
+/*
+ * Determine the effective resource range and vmem_altmap from an nd_pfn
+ * instance.
+ */
+struct vmem_altmap *nvdimm_setup_pfn(struct nd_pfn *nd_pfn,
+		struct resource *res, struct vmem_altmap *altmap)
+{
+	int rc;
+
+	if (!nd_pfn->uuid || !nd_pfn->ndns)
+		return ERR_PTR(-ENODEV);
+
+	rc = nd_pfn_init(nd_pfn);
+	if (rc)
+		return ERR_PTR(rc);
+
+	/* we need a valid pfn_sb before we can init a vmem_altmap */
+	return __nvdimm_setup_pfn(nd_pfn, res, altmap);
+}
+EXPORT_SYMBOL_GPL(nvdimm_setup_pfn);