linux-stable/include/linux/libnvdimm.h
Dan Williams 5813882094 libnvdimm, nfit: handle unarmed dimms, mark namespaces read-only
Upon detection of an unarmed dimm in a region, arrange for descendant
BTT, PMEM, or BLK instances to be read-only.  A dimm is primarily marked
"unarmed" via flags passed by platform firmware (NFIT).

The flags in the NFIT memory device sub-structure indicate the state of
the data on the nvdimm relative to its energy source or last "flush to
persistence".  For the most part there is nothing the driver can do but
advertise the state of these flags in sysfs and emit a message if
firmware indicates that the contents of the device may be corrupted.
However, for the case of ACPI_NFIT_MEM_ARMED, the driver can arrange for
the block devices incorporating that nvdimm to be marked read-only.
This is a safe default as the data is still available and new writes are
held off until the administrator either forces read-write mode, or the
energy source becomes armed.

A 'read_only' attribute is added to REGION devices to allow for
overriding the default read-only policy of all descendant block devices.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-26 11:23:38 -04:00

149 lines
5.1 KiB
C

/*
* libnvdimm - Non-volatile-memory Devices Subsystem
*
* 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.
*/
#ifndef __LIBNVDIMM_H__
#define __LIBNVDIMM_H__
#include <linux/kernel.h>
#include <linux/sizes.h>
#include <linux/types.h>
enum {
/* when a dimm supports both PMEM and BLK access a label is required */
NDD_ALIASING = 1 << 0,
/* unarmed memory devices may not persist writes */
NDD_UNARMED = 1 << 1,
/* need to set a limit somewhere, but yes, this is likely overkill */
ND_IOCTL_MAX_BUFLEN = SZ_4M,
ND_CMD_MAX_ELEM = 4,
ND_CMD_MAX_ENVELOPE = 16,
ND_CMD_ARS_STATUS_MAX = SZ_4K,
ND_MAX_MAPPINGS = 32,
/* mark newly adjusted resources as requiring a label update */
DPA_RESOURCE_ADJUSTED = 1 << 0,
};
extern struct attribute_group nvdimm_bus_attribute_group;
extern struct attribute_group nvdimm_attribute_group;
extern struct attribute_group nd_device_attribute_group;
extern struct attribute_group nd_region_attribute_group;
extern struct attribute_group nd_mapping_attribute_group;
struct nvdimm;
struct nvdimm_bus_descriptor;
typedef int (*ndctl_fn)(struct nvdimm_bus_descriptor *nd_desc,
struct nvdimm *nvdimm, unsigned int cmd, void *buf,
unsigned int buf_len);
struct nd_namespace_label;
struct nvdimm_drvdata;
struct nd_mapping {
struct nvdimm *nvdimm;
struct nd_namespace_label **labels;
u64 start;
u64 size;
/*
* @ndd is for private use at region enable / disable time for
* get_ndd() + put_ndd(), all other nd_mapping to ndd
* conversions use to_ndd() which respects enabled state of the
* nvdimm.
*/
struct nvdimm_drvdata *ndd;
};
struct nvdimm_bus_descriptor {
const struct attribute_group **attr_groups;
unsigned long dsm_mask;
char *provider_name;
ndctl_fn ndctl;
};
struct nd_cmd_desc {
int in_num;
int out_num;
u32 in_sizes[ND_CMD_MAX_ELEM];
int out_sizes[ND_CMD_MAX_ELEM];
};
struct nd_interleave_set {
u64 cookie;
};
struct nd_region_desc {
struct resource *res;
struct nd_mapping *nd_mapping;
u16 num_mappings;
const struct attribute_group **attr_groups;
struct nd_interleave_set *nd_set;
void *provider_data;
int num_lanes;
};
struct nvdimm_bus;
struct module;
struct device;
struct nd_blk_region;
struct nd_blk_region_desc {
int (*enable)(struct nvdimm_bus *nvdimm_bus, struct device *dev);
void (*disable)(struct nvdimm_bus *nvdimm_bus, struct device *dev);
int (*do_io)(struct nd_blk_region *ndbr, resource_size_t dpa,
void *iobuf, u64 len, int rw);
struct nd_region_desc ndr_desc;
};
static inline struct nd_blk_region_desc *to_blk_region_desc(
struct nd_region_desc *ndr_desc)
{
return container_of(ndr_desc, struct nd_blk_region_desc, ndr_desc);
}
struct nvdimm_bus *__nvdimm_bus_register(struct device *parent,
struct nvdimm_bus_descriptor *nfit_desc, struct module *module);
#define nvdimm_bus_register(parent, desc) \
__nvdimm_bus_register(parent, desc, THIS_MODULE)
void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus);
struct nvdimm_bus *to_nvdimm_bus(struct device *dev);
struct nvdimm *to_nvdimm(struct device *dev);
struct nd_region *to_nd_region(struct device *dev);
struct nd_blk_region *to_nd_blk_region(struct device *dev);
struct nvdimm_bus_descriptor *to_nd_desc(struct nvdimm_bus *nvdimm_bus);
const char *nvdimm_name(struct nvdimm *nvdimm);
void *nvdimm_provider_data(struct nvdimm *nvdimm);
struct nvdimm *nvdimm_create(struct nvdimm_bus *nvdimm_bus, void *provider_data,
const struct attribute_group **groups, unsigned long flags,
unsigned long *dsm_mask);
const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd);
const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd);
u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
const struct nd_cmd_desc *desc, int idx, void *buf);
u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
const u32 *out_field);
int nvdimm_bus_check_dimm_count(struct nvdimm_bus *nvdimm_bus, int dimm_count);
struct nd_region *nvdimm_pmem_region_create(struct nvdimm_bus *nvdimm_bus,
struct nd_region_desc *ndr_desc);
struct nd_region *nvdimm_blk_region_create(struct nvdimm_bus *nvdimm_bus,
struct nd_region_desc *ndr_desc);
struct nd_region *nvdimm_volatile_region_create(struct nvdimm_bus *nvdimm_bus,
struct nd_region_desc *ndr_desc);
void *nd_region_provider_data(struct nd_region *nd_region);
void *nd_blk_region_provider_data(struct nd_blk_region *ndbr);
void nd_blk_region_set_provider_data(struct nd_blk_region *ndbr, void *data);
struct nvdimm *nd_blk_region_to_dimm(struct nd_blk_region *ndbr);
unsigned int nd_region_acquire_lane(struct nd_region *nd_region);
void nd_region_release_lane(struct nd_region *nd_region, unsigned int lane);
u64 nd_fletcher64(void *addr, size_t len, bool le);
#endif /* __LIBNVDIMM_H__ */