202 lines
5.0 KiB
C
202 lines
5.0 KiB
C
|
/* SPDX-License-Identifier: GPL-2.0 */
|
||
|
/*
|
||
|
* Simple zone file system for zoned block devices.
|
||
|
*
|
||
|
* Copyright (C) 2019 Western Digital Corporation or its affiliates.
|
||
|
*/
|
||
|
#ifndef __ZONEFS_H__
|
||
|
#define __ZONEFS_H__
|
||
|
|
||
|
#include <linux/fs.h>
|
||
|
#include <linux/magic.h>
|
||
|
#include <linux/uuid.h>
|
||
|
#include <linux/mutex.h>
|
||
|
#include <linux/rwsem.h>
|
||
|
|
||
|
/*
|
||
|
* Maximum length of file names: this only needs to be large enough to fit
|
||
|
* the zone group directory names and a decimal zone number for file names.
|
||
|
* 16 characters is plenty.
|
||
|
*/
|
||
|
#define ZONEFS_NAME_MAX 16
|
||
|
|
||
|
/*
|
||
|
* Zone types: ZONEFS_ZTYPE_SEQ is used for all sequential zone types
|
||
|
* defined in linux/blkzoned.h, that is, BLK_ZONE_TYPE_SEQWRITE_REQ and
|
||
|
* BLK_ZONE_TYPE_SEQWRITE_PREF.
|
||
|
*/
|
||
|
enum zonefs_ztype {
|
||
|
ZONEFS_ZTYPE_CNV,
|
||
|
ZONEFS_ZTYPE_SEQ,
|
||
|
ZONEFS_ZTYPE_MAX,
|
||
|
};
|
||
|
|
||
|
static inline enum zonefs_ztype zonefs_zone_type(struct blk_zone *zone)
|
||
|
{
|
||
|
if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
|
||
|
return ZONEFS_ZTYPE_CNV;
|
||
|
return ZONEFS_ZTYPE_SEQ;
|
||
|
}
|
||
|
|
||
|
#define ZONEFS_ZONE_OPEN (1 << 0)
|
||
|
|
||
|
/*
|
||
|
* In-memory inode data.
|
||
|
*/
|
||
|
struct zonefs_inode_info {
|
||
|
struct inode i_vnode;
|
||
|
|
||
|
/* File zone type */
|
||
|
enum zonefs_ztype i_ztype;
|
||
|
|
||
|
/* File zone start sector (512B unit) */
|
||
|
sector_t i_zsector;
|
||
|
|
||
|
/* File zone write pointer position (sequential zones only) */
|
||
|
loff_t i_wpoffset;
|
||
|
|
||
|
/* File maximum size */
|
||
|
loff_t i_max_size;
|
||
|
|
||
|
/* File zone size */
|
||
|
loff_t i_zone_size;
|
||
|
|
||
|
/*
|
||
|
* To serialise fully against both syscall and mmap based IO and
|
||
|
* sequential file truncation, two locks are used. For serializing
|
||
|
* zonefs_seq_file_truncate() against zonefs_iomap_begin(), that is,
|
||
|
* file truncate operations against block mapping, i_truncate_mutex is
|
||
|
* used. i_truncate_mutex also protects against concurrent accesses
|
||
|
* and changes to the inode private data, and in particular changes to
|
||
|
* a sequential file size on completion of direct IO writes.
|
||
|
* Serialization of mmap read IOs with truncate and syscall IO
|
||
|
* operations is done with invalidate_lock in addition to
|
||
|
* i_truncate_mutex. Only zonefs_seq_file_truncate() takes both lock
|
||
|
* (invalidate_lock first, i_truncate_mutex second).
|
||
|
*/
|
||
|
struct mutex i_truncate_mutex;
|
||
|
|
||
|
/* guarded by i_truncate_mutex */
|
||
|
unsigned int i_wr_refcnt;
|
||
|
unsigned int i_flags;
|
||
|
};
|
||
|
|
||
|
static inline struct zonefs_inode_info *ZONEFS_I(struct inode *inode)
|
||
|
{
|
||
|
return container_of(inode, struct zonefs_inode_info, i_vnode);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* On-disk super block (block 0).
|
||
|
*/
|
||
|
#define ZONEFS_LABEL_LEN 64
|
||
|
#define ZONEFS_UUID_SIZE 16
|
||
|
#define ZONEFS_SUPER_SIZE 4096
|
||
|
|
||
|
struct zonefs_super {
|
||
|
|
||
|
/* Magic number */
|
||
|
__le32 s_magic;
|
||
|
|
||
|
/* Checksum */
|
||
|
__le32 s_crc;
|
||
|
|
||
|
/* Volume label */
|
||
|
char s_label[ZONEFS_LABEL_LEN];
|
||
|
|
||
|
/* 128-bit uuid */
|
||
|
__u8 s_uuid[ZONEFS_UUID_SIZE];
|
||
|
|
||
|
/* Features */
|
||
|
__le64 s_features;
|
||
|
|
||
|
/* UID/GID to use for files */
|
||
|
__le32 s_uid;
|
||
|
__le32 s_gid;
|
||
|
|
||
|
/* File permissions */
|
||
|
__le32 s_perm;
|
||
|
|
||
|
/* Padding to ZONEFS_SUPER_SIZE bytes */
|
||
|
__u8 s_reserved[3988];
|
||
|
|
||
|
} __packed;
|
||
|
|
||
|
/*
|
||
|
* Feature flags: specified in the s_features field of the on-disk super
|
||
|
* block struct zonefs_super and in-memory in the s_feartures field of
|
||
|
* struct zonefs_sb_info.
|
||
|
*/
|
||
|
enum zonefs_features {
|
||
|
/*
|
||
|
* Aggregate contiguous conventional zones into a single file.
|
||
|
*/
|
||
|
ZONEFS_F_AGGRCNV = 1ULL << 0,
|
||
|
/*
|
||
|
* Use super block specified UID for files instead of default 0.
|
||
|
*/
|
||
|
ZONEFS_F_UID = 1ULL << 1,
|
||
|
/*
|
||
|
* Use super block specified GID for files instead of default 0.
|
||
|
*/
|
||
|
ZONEFS_F_GID = 1ULL << 2,
|
||
|
/*
|
||
|
* Use super block specified file permissions instead of default 640.
|
||
|
*/
|
||
|
ZONEFS_F_PERM = 1ULL << 3,
|
||
|
};
|
||
|
|
||
|
#define ZONEFS_F_DEFINED_FEATURES \
|
||
|
(ZONEFS_F_AGGRCNV | ZONEFS_F_UID | ZONEFS_F_GID | ZONEFS_F_PERM)
|
||
|
|
||
|
/*
|
||
|
* Mount options for zone write pointer error handling.
|
||
|
*/
|
||
|
#define ZONEFS_MNTOPT_ERRORS_RO (1 << 0) /* Make zone file readonly */
|
||
|
#define ZONEFS_MNTOPT_ERRORS_ZRO (1 << 1) /* Make zone file offline */
|
||
|
#define ZONEFS_MNTOPT_ERRORS_ZOL (1 << 2) /* Make zone file offline */
|
||
|
#define ZONEFS_MNTOPT_ERRORS_REPAIR (1 << 3) /* Remount read-only */
|
||
|
#define ZONEFS_MNTOPT_ERRORS_MASK \
|
||
|
(ZONEFS_MNTOPT_ERRORS_RO | ZONEFS_MNTOPT_ERRORS_ZRO | \
|
||
|
ZONEFS_MNTOPT_ERRORS_ZOL | ZONEFS_MNTOPT_ERRORS_REPAIR)
|
||
|
#define ZONEFS_MNTOPT_EXPLICIT_OPEN (1 << 4) /* Explicit open/close of zones on open/close */
|
||
|
|
||
|
/*
|
||
|
* In-memory Super block information.
|
||
|
*/
|
||
|
struct zonefs_sb_info {
|
||
|
|
||
|
unsigned long s_mount_opts;
|
||
|
|
||
|
spinlock_t s_lock;
|
||
|
|
||
|
unsigned long long s_features;
|
||
|
kuid_t s_uid;
|
||
|
kgid_t s_gid;
|
||
|
umode_t s_perm;
|
||
|
uuid_t s_uuid;
|
||
|
unsigned int s_zone_sectors_shift;
|
||
|
|
||
|
unsigned int s_nr_files[ZONEFS_ZTYPE_MAX];
|
||
|
|
||
|
loff_t s_blocks;
|
||
|
loff_t s_used_blocks;
|
||
|
|
||
|
unsigned int s_max_open_zones;
|
||
|
atomic_t s_open_zones;
|
||
|
};
|
||
|
|
||
|
static inline struct zonefs_sb_info *ZONEFS_SB(struct super_block *sb)
|
||
|
{
|
||
|
return sb->s_fs_info;
|
||
|
}
|
||
|
|
||
|
#define zonefs_info(sb, format, args...) \
|
||
|
pr_info("zonefs (%s): " format, sb->s_id, ## args)
|
||
|
#define zonefs_err(sb, format, args...) \
|
||
|
pr_err("zonefs (%s) ERROR: " format, sb->s_id, ## args)
|
||
|
#define zonefs_warn(sb, format, args...) \
|
||
|
pr_warn("zonefs (%s) WARNING: " format, sb->s_id, ## args)
|
||
|
|
||
|
#endif
|