OpenCloudOS-Kernel/drivers/nvdimm/btt_devs.c

426 lines
10 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 "btt.h"
#include "nd.h"
static void __nd_btt_detach_ndns(struct nd_btt *nd_btt)
{
struct nd_namespace_common *ndns = nd_btt->ndns;
dev_WARN_ONCE(&nd_btt->dev, !mutex_is_locked(&ndns->dev.mutex)
|| ndns->claim != &nd_btt->dev,
"%s: invalid claim\n", __func__);
ndns->claim = NULL;
nd_btt->ndns = NULL;
put_device(&ndns->dev);
}
static void nd_btt_detach_ndns(struct nd_btt *nd_btt)
{
struct nd_namespace_common *ndns = nd_btt->ndns;
if (!ndns)
return;
get_device(&ndns->dev);
device_lock(&ndns->dev);
__nd_btt_detach_ndns(nd_btt);
device_unlock(&ndns->dev);
put_device(&ndns->dev);
}
static bool __nd_btt_attach_ndns(struct nd_btt *nd_btt,
struct nd_namespace_common *ndns)
{
if (ndns->claim)
return false;
dev_WARN_ONCE(&nd_btt->dev, !mutex_is_locked(&ndns->dev.mutex)
|| nd_btt->ndns,
"%s: invalid claim\n", __func__);
ndns->claim = &nd_btt->dev;
nd_btt->ndns = ndns;
get_device(&ndns->dev);
return true;
}
static bool nd_btt_attach_ndns(struct nd_btt *nd_btt,
struct nd_namespace_common *ndns)
{
bool claimed;
device_lock(&ndns->dev);
claimed = __nd_btt_attach_ndns(nd_btt, ndns);
device_unlock(&ndns->dev);
return claimed;
}
static void nd_btt_release(struct device *dev)
{
struct nd_region *nd_region = to_nd_region(dev->parent);
struct nd_btt *nd_btt = to_nd_btt(dev);
dev_dbg(dev, "%s\n", __func__);
nd_btt_detach_ndns(nd_btt);
ida_simple_remove(&nd_region->btt_ida, nd_btt->id);
kfree(nd_btt->uuid);
kfree(nd_btt);
}
static struct device_type nd_btt_device_type = {
.name = "nd_btt",
.release = nd_btt_release,
};
bool is_nd_btt(struct device *dev)
{
return dev->type == &nd_btt_device_type;
}
EXPORT_SYMBOL(is_nd_btt);
struct nd_btt *to_nd_btt(struct device *dev)
{
struct nd_btt *nd_btt = container_of(dev, struct nd_btt, dev);
WARN_ON(!is_nd_btt(dev));
return nd_btt;
}
EXPORT_SYMBOL(to_nd_btt);
static const unsigned long btt_lbasize_supported[] = { 512, 520, 528,
4096, 4104, 4160, 4224, 0 };
static ssize_t sector_size_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_btt *nd_btt = to_nd_btt(dev);
return nd_sector_size_show(nd_btt->lbasize, btt_lbasize_supported, buf);
}
static ssize_t sector_size_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t len)
{
struct nd_btt *nd_btt = to_nd_btt(dev);
ssize_t rc;
device_lock(dev);
nvdimm_bus_lock(dev);
rc = nd_sector_size_store(dev, buf, &nd_btt->lbasize,
btt_lbasize_supported);
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(sector_size);
static ssize_t uuid_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_btt *nd_btt = to_nd_btt(dev);
if (nd_btt->uuid)
return sprintf(buf, "%pUb\n", nd_btt->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_btt *nd_btt = to_nd_btt(dev);
ssize_t rc;
device_lock(dev);
rc = nd_uuid_store(dev, &nd_btt->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_btt *nd_btt = to_nd_btt(dev);
ssize_t rc;
nvdimm_bus_lock(dev);
rc = sprintf(buf, "%s\n", nd_btt->ndns
? dev_name(&nd_btt->ndns->dev) : "");
nvdimm_bus_unlock(dev);
return rc;
}
static int namespace_match(struct device *dev, void *data)
{
char *name = data;
return strcmp(name, dev_name(dev)) == 0;
}
static bool is_nd_btt_idle(struct device *dev)
{
struct nd_region *nd_region = to_nd_region(dev->parent);
struct nd_btt *nd_btt = to_nd_btt(dev);
if (nd_region->btt_seed == dev || nd_btt->ndns || dev->driver)
return false;
return true;
}
static ssize_t __namespace_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t len)
{
struct nd_btt *nd_btt = to_nd_btt(dev);
struct nd_namespace_common *ndns;
struct device *found;
char *name;
if (dev->driver) {
dev_dbg(dev, "%s: -EBUSY\n", __func__);
return -EBUSY;
}
name = kstrndup(buf, len, GFP_KERNEL);
if (!name)
return -ENOMEM;
strim(name);
if (strncmp(name, "namespace", 9) == 0 || strcmp(name, "") == 0)
/* pass */;
else {
len = -EINVAL;
goto out;
}
ndns = nd_btt->ndns;
if (strcmp(name, "") == 0) {
/* detach the namespace and destroy / reset the btt device */
nd_btt_detach_ndns(nd_btt);
if (is_nd_btt_idle(dev))
nd_device_unregister(dev, ND_ASYNC);
else {
nd_btt->lbasize = 0;
kfree(nd_btt->uuid);
nd_btt->uuid = NULL;
}
goto out;
} else if (ndns) {
dev_dbg(dev, "namespace already set to: %s\n",
dev_name(&ndns->dev));
len = -EBUSY;
goto out;
}
found = device_find_child(dev->parent, name, namespace_match);
if (!found) {
dev_dbg(dev, "'%s' not found under %s\n", name,
dev_name(dev->parent));
len = -ENODEV;
goto out;
}
ndns = to_ndns(found);
if (__nvdimm_namespace_capacity(ndns) < SZ_16M) {
dev_dbg(dev, "%s too small to host btt\n", name);
len = -ENXIO;
goto out_attach;
}
WARN_ON_ONCE(!is_nvdimm_bus_locked(&nd_btt->dev));
if (!nd_btt_attach_ndns(nd_btt, ndns)) {
dev_dbg(dev, "%s already claimed\n",
dev_name(&ndns->dev));
len = -EBUSY;
}
out_attach:
put_device(&ndns->dev); /* from device_find_child */
out:
kfree(name);
return len;
}
static ssize_t namespace_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t len)
{
ssize_t rc;
nvdimm_bus_lock(dev);
device_lock(dev);
rc = __namespace_store(dev, attr, buf, len);
dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__,
rc, buf, buf[len - 1] == '\n' ? "" : "\n");
device_unlock(dev);
nvdimm_bus_unlock(dev);
return rc;
}
static DEVICE_ATTR_RW(namespace);
static struct attribute *nd_btt_attributes[] = {
&dev_attr_sector_size.attr,
&dev_attr_namespace.attr,
&dev_attr_uuid.attr,
NULL,
};
static struct attribute_group nd_btt_attribute_group = {
.attrs = nd_btt_attributes,
};
static const struct attribute_group *nd_btt_attribute_groups[] = {
&nd_btt_attribute_group,
&nd_device_attribute_group,
&nd_numa_attribute_group,
NULL,
};
static struct device *__nd_btt_create(struct nd_region *nd_region,
unsigned long lbasize, u8 *uuid,
struct nd_namespace_common *ndns)
{
struct nd_btt *nd_btt;
struct device *dev;
nd_btt = kzalloc(sizeof(*nd_btt), GFP_KERNEL);
if (!nd_btt)
return NULL;
nd_btt->id = ida_simple_get(&nd_region->btt_ida, 0, 0, GFP_KERNEL);
if (nd_btt->id < 0) {
kfree(nd_btt);
return NULL;
}
nd_btt->lbasize = lbasize;
if (uuid)
uuid = kmemdup(uuid, 16, GFP_KERNEL);
nd_btt->uuid = uuid;
dev = &nd_btt->dev;
dev_set_name(dev, "btt%d.%d", nd_region->id, nd_btt->id);
dev->parent = &nd_region->dev;
dev->type = &nd_btt_device_type;
dev->groups = nd_btt_attribute_groups;
device_initialize(&nd_btt->dev);
if (ndns && !__nd_btt_attach_ndns(nd_btt, 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_btt_create(struct nd_region *nd_region)
{
struct device *dev = __nd_btt_create(nd_region, 0, NULL, NULL);
if (dev)
__nd_device_register(dev);
return dev;
}
/*
* nd_btt_sb_checksum: compute checksum for btt info block
*
* Returns a fletcher64 checksum of everything in the given info block
* except the last field (since that's where the checksum lives).
*/
u64 nd_btt_sb_checksum(struct btt_sb *btt_sb)
{
u64 sum;
__le64 sum_save;
sum_save = btt_sb->checksum;
btt_sb->checksum = 0;
sum = nd_fletcher64(btt_sb, sizeof(*btt_sb), 1);
btt_sb->checksum = sum_save;
return sum;
}
EXPORT_SYMBOL(nd_btt_sb_checksum);
static int __nd_btt_probe(struct nd_btt *nd_btt,
struct nd_namespace_common *ndns, struct btt_sb *btt_sb)
{
u64 checksum;
if (!btt_sb || !ndns || !nd_btt)
return -ENODEV;
if (nvdimm_read_bytes(ndns, SZ_4K, btt_sb, sizeof(*btt_sb)))
return -ENXIO;
if (nvdimm_namespace_capacity(ndns) < SZ_16M)
return -ENXIO;
if (memcmp(btt_sb->signature, BTT_SIG, BTT_SIG_LEN) != 0)
return -ENODEV;
checksum = le64_to_cpu(btt_sb->checksum);
btt_sb->checksum = 0;
if (checksum != nd_btt_sb_checksum(btt_sb))
return -ENODEV;
btt_sb->checksum = cpu_to_le64(checksum);
nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize);
nd_btt->uuid = kmemdup(btt_sb->uuid, 16, GFP_KERNEL);
if (!nd_btt->uuid)
return -ENOMEM;
__nd_device_register(&nd_btt->dev);
return 0;
}
int nd_btt_probe(struct nd_namespace_common *ndns, void *drvdata)
{
int rc;
struct device *dev;
struct btt_sb *btt_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_btt_create(nd_region, 0, NULL, ndns);
nvdimm_bus_unlock(&ndns->dev);
if (!dev)
return -ENOMEM;
dev_set_drvdata(dev, drvdata);
btt_sb = kzalloc(sizeof(*btt_sb), GFP_KERNEL);
rc = __nd_btt_probe(to_nd_btt(dev), ndns, btt_sb);
kfree(btt_sb);
dev_dbg(&ndns->dev, "%s: btt: %s\n", __func__,
rc == 0 ? dev_name(dev) : "<none>");
if (rc < 0) {
__nd_btt_detach_ndns(to_nd_btt(dev));
put_device(dev);
}
return rc;
}
EXPORT_SYMBOL(nd_btt_probe);