linux/drivers/nvdimm/label.h
Alexander Duyck 7d47aad457 nvdimm: Use namespace index data to reduce number of label reads needed
This patch adds logic that is meant to make use of the namespace index data
to reduce the number of reads that are needed to initialize a given
namespace. The general idea is that once we have enough data to validate
the namespace index we do so and then proceed to fetch only those labels
that are not listed as being "free". By doing this I am seeing a total time
reduction from about 4-5 seconds to 2-3 seconds for 24 NVDIMM modules each
with 128K of label config area.

Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-10-12 08:39:31 -07:00

157 lines
4.5 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.
*/
#ifndef __LABEL_H__
#define __LABEL_H__
#include <linux/ndctl.h>
#include <linux/sizes.h>
#include <linux/uuid.h>
#include <linux/io.h>
enum {
NSINDEX_SIG_LEN = 16,
NSINDEX_ALIGN = 256,
NSINDEX_SEQ_MASK = 0x3,
NSLABEL_UUID_LEN = 16,
NSLABEL_NAME_LEN = 64,
NSLABEL_FLAG_ROLABEL = 0x1, /* read-only label */
NSLABEL_FLAG_LOCAL = 0x2, /* DIMM-local namespace */
NSLABEL_FLAG_BTT = 0x4, /* namespace contains a BTT */
NSLABEL_FLAG_UPDATING = 0x8, /* label being updated */
BTT_ALIGN = 4096, /* all btt structures */
BTTINFO_SIG_LEN = 16,
BTTINFO_UUID_LEN = 16,
BTTINFO_FLAG_ERROR = 0x1, /* error state (read-only) */
BTTINFO_MAJOR_VERSION = 1,
ND_LABEL_MIN_SIZE = 256 * 4, /* see sizeof_namespace_index() */
ND_LABEL_ID_SIZE = 50,
ND_NSINDEX_INIT = 0x1,
};
static const char NSINDEX_SIGNATURE[] = "NAMESPACE_INDEX\0";
/**
* struct nd_namespace_index - label set superblock
* @sig: NAMESPACE_INDEX\0
* @flags: placeholder
* @seq: sequence number for this index
* @myoff: offset of this index in label area
* @mysize: size of this index struct
* @otheroff: offset of other index
* @labeloff: offset of first label slot
* @nslot: total number of label slots
* @major: label area major version
* @minor: label area minor version
* @checksum: fletcher64 of all fields
* @free[0]: bitmap, nlabel bits
*
* The size of free[] is rounded up so the total struct size is a
* multiple of NSINDEX_ALIGN bytes. Any bits this allocates beyond
* nlabel bits must be zero.
*/
struct nd_namespace_index {
u8 sig[NSINDEX_SIG_LEN];
u8 flags[3];
u8 labelsize;
__le32 seq;
__le64 myoff;
__le64 mysize;
__le64 otheroff;
__le64 labeloff;
__le32 nslot;
__le16 major;
__le16 minor;
__le64 checksum;
u8 free[0];
};
/**
* struct nd_namespace_label - namespace superblock
* @uuid: UUID per RFC 4122
* @name: optional name (NULL-terminated)
* @flags: see NSLABEL_FLAG_*
* @nlabel: num labels to describe this ns
* @position: labels position in set
* @isetcookie: interleave set cookie
* @lbasize: LBA size in bytes or 0 for pmem
* @dpa: DPA of NVM range on this DIMM
* @rawsize: size of namespace
* @slot: slot of this label in label area
* @unused: must be zero
*/
struct nd_namespace_label {
u8 uuid[NSLABEL_UUID_LEN];
u8 name[NSLABEL_NAME_LEN];
__le32 flags;
__le16 nlabel;
__le16 position;
__le64 isetcookie;
__le64 lbasize;
__le64 dpa;
__le64 rawsize;
__le32 slot;
/*
* Accessing fields past this point should be gated by a
* namespace_label_has() check.
*/
u8 align;
u8 reserved[3];
guid_t type_guid;
guid_t abstraction_guid;
u8 reserved2[88];
__le64 checksum;
};
#define NVDIMM_BTT_GUID "8aed63a2-29a2-4c66-8b12-f05d15d3922a"
#define NVDIMM_BTT2_GUID "18633bfc-1735-4217-8ac9-17239282d3f8"
#define NVDIMM_PFN_GUID "266400ba-fb9f-4677-bcb0-968f11d0d225"
#define NVDIMM_DAX_GUID "97a86d9c-3cdd-4eda-986f-5068b4f80088"
/**
* struct nd_label_id - identifier string for dpa allocation
* @id: "{blk|pmem}-<namespace uuid>"
*/
struct nd_label_id {
char id[ND_LABEL_ID_SIZE];
};
/*
* If the 'best' index is invalid, so is the 'next' index. Otherwise,
* the next index is MOD(index+1, 2)
*/
static inline int nd_label_next_nsindex(int index)
{
if (index < 0)
return -1;
return (index + 1) % 2;
}
struct nvdimm_drvdata;
int nd_label_data_init(struct nvdimm_drvdata *ndd);
size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd);
int nd_label_active_count(struct nvdimm_drvdata *ndd);
struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n);
u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd);
bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot);
u32 nd_label_nfree(struct nvdimm_drvdata *ndd);
enum nvdimm_claim_class to_nvdimm_cclass(guid_t *guid);
struct nd_region;
struct nd_namespace_pmem;
struct nd_namespace_blk;
int nd_pmem_namespace_label_update(struct nd_region *nd_region,
struct nd_namespace_pmem *nspm, resource_size_t size);
int nd_blk_namespace_label_update(struct nd_region *nd_region,
struct nd_namespace_blk *nsblk, resource_size_t size);
#endif /* __LABEL_H__ */