linux/drivers/nvdimm/pfn_devs.c
Dan Williams e5670563f5 libnvdimm, pfn: fix uuid validation
If we detect a namespace has a stale info block in the init path, we
should overwrite with the latest configuration.  In fact, we already
return -ENODEV when the parent uuid is invalid, the same should be done
for the 'self' uuid.  Otherwise we can get into a condition where
userspace is unable to reconfigure the pfn-device without directly /
manually invalidating the info block.

Cc: <stable@vger.kernel.org>
Reported-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-07 19:59:27 -07:00

447 lines
11 KiB
C

/*
* 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) {
nd_pfn->mode = PFN_MODE_PMEM;
} 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 align_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_pfn *nd_pfn = to_nd_pfn(dev);
return sprintf(buf, "%lx\n", nd_pfn->align);
}
static ssize_t __align_store(struct nd_pfn *nd_pfn, const char *buf)
{
unsigned long val;
int rc;
rc = kstrtoul(buf, 0, &val);
if (rc)
return rc;
if (!is_power_of_2(val) || val < PAGE_SIZE || val > SZ_1G)
return -EINVAL;
if (nd_pfn->dev.driver)
return -EBUSY;
else
nd_pfn->align = val;
return 0;
}
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);
ssize_t rc;
device_lock(dev);
nvdimm_bus_lock(dev);
rc = __align_store(nd_pfn, buf);
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(align);
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 ssize_t resource_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_pfn *nd_pfn = to_nd_pfn(dev);
ssize_t rc;
device_lock(dev);
if (dev->driver) {
struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
u64 offset = __le64_to_cpu(pfn_sb->dataoff);
struct nd_namespace_common *ndns = nd_pfn->ndns;
u32 start_pad = __le32_to_cpu(pfn_sb->start_pad);
struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
rc = sprintf(buf, "%#llx\n", (unsigned long long) nsio->res.start
+ start_pad + offset);
} else {
/* no address to convey if the pfn instance is disabled */
rc = -ENXIO;
}
device_unlock(dev);
return rc;
}
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);
ssize_t rc;
device_lock(dev);
if (dev->driver) {
struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
u64 offset = __le64_to_cpu(pfn_sb->dataoff);
struct nd_namespace_common *ndns = nd_pfn->ndns;
u32 start_pad = __le32_to_cpu(pfn_sb->start_pad);
u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
rc = sprintf(buf, "%llu\n", (unsigned long long)
resource_size(&nsio->res) - start_pad
- end_trunc - offset);
} else {
/* no size to convey if the pfn instance is disabled */
rc = -ENXIO;
}
device_unlock(dev);
return rc;
}
static DEVICE_ATTR_RO(size);
static struct attribute *nd_pfn_attributes[] = {
&dev_attr_mode.attr,
&dev_attr_namespace.attr,
&dev_attr_uuid.attr,
&dev_attr_align.attr,
&dev_attr_resource.attr,
&dev_attr_size.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,
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 = 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;
}
struct device *nd_pfn_create(struct nd_region *nd_region)
{
struct device *dev = __nd_pfn_create(nd_region, NULL);
if (dev)
__nd_device_register(dev);
return dev;
}
int nd_pfn_validate(struct nd_pfn *nd_pfn)
{
u64 checksum, offset;
struct nd_namespace_io *nsio;
struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
struct nd_namespace_common *ndns = nd_pfn->ndns;
const u8 *parent_uuid = nd_dev_to_uuid(&ndns->dev);
if (!pfn_sb || !ndns)
return -ENODEV;
if (!is_nd_pmem(nd_pfn->dev.parent))
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);
if (memcmp(pfn_sb->parent_uuid, parent_uuid, 16) != 0)
return -ENODEV;
if (__le16_to_cpu(pfn_sb->version_minor) < 1) {
pfn_sb->start_pad = 0;
pfn_sb->end_trunc = 0;
}
switch (le32_to_cpu(pfn_sb->mode)) {
case PFN_MODE_RAM:
case PFN_MODE_PMEM:
break;
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 -ENODEV;
}
if (nd_pfn->align > nvdimm_namespace_capacity(ndns)) {
dev_err(&nd_pfn->dev, "alignment: %lx exceeds capacity %llx\n",
nd_pfn->align, nvdimm_namespace_capacity(ndns));
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 (offset >= resource_size(&nsio->res)) {
dev_err(&nd_pfn->dev, "pfn array size exceeds capacity of %s\n",
dev_name(&ndns->dev));
return -EBUSY;
}
nd_pfn->align = 1UL << ilog2(offset);
if (!is_power_of_2(offset) || offset < PAGE_SIZE) {
dev_err(&nd_pfn->dev, "bad offset: %#llx dax disabled\n",
offset);
return -ENXIO;
}
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, 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);