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brintos / linux-shallow public Read only

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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * Simple zone file system for zoned block devices.4 *5 * Copyright (C) 2019 Western Digital Corporation or its affiliates.6 */7#ifndef __ZONEFS_H__8#define __ZONEFS_H__9 10#include <linux/fs.h>11#include <linux/magic.h>12#include <linux/uuid.h>13#include <linux/mutex.h>14#include <linux/rwsem.h>15#include <linux/kobject.h>16 17/*18 * Maximum length of file names: this only needs to be large enough to fit19 * the zone group directory names and a decimal zone number for file names.20 * 16 characters is plenty.21 */22#define ZONEFS_NAME_MAX		1623 24/*25 * Zone types: ZONEFS_ZTYPE_SEQ is used for all sequential zone types26 * defined in linux/blkzoned.h, that is, BLK_ZONE_TYPE_SEQWRITE_REQ and27 * BLK_ZONE_TYPE_SEQWRITE_PREF.28 */29enum zonefs_ztype {30	ZONEFS_ZTYPE_CNV,31	ZONEFS_ZTYPE_SEQ,32	ZONEFS_ZTYPE_MAX,33};34 35static inline enum zonefs_ztype zonefs_zone_type(struct blk_zone *zone)36{37	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)38		return ZONEFS_ZTYPE_CNV;39	return ZONEFS_ZTYPE_SEQ;40}41 42#define ZONEFS_ZONE_INIT_MODE	(1U << 0)43#define ZONEFS_ZONE_OPEN	(1U << 1)44#define ZONEFS_ZONE_ACTIVE	(1U << 2)45#define ZONEFS_ZONE_OFFLINE	(1U << 3)46#define ZONEFS_ZONE_READONLY	(1U << 4)47#define ZONEFS_ZONE_CNV		(1U << 31)48 49/*50 * In-memory per-file inode zone data.51 */52struct zonefs_zone {53	/* Zone state flags */54	unsigned int		z_flags;55 56	/* Zone start sector (512B unit) */57	sector_t		z_sector;58 59	/* Zone size (bytes) */60	loff_t			z_size;61 62	/* Zone capacity (file maximum size, bytes) */63	loff_t			z_capacity;64 65	/* Write pointer offset in the zone (sequential zones only, bytes) */66	loff_t			z_wpoffset;67 68	/* Saved inode uid, gid and access rights */69	umode_t			z_mode;70	kuid_t			z_uid;71	kgid_t			z_gid;72};73 74/*75 * In memory zone group information: all zones of a group are exposed76 * as files, one file per zone.77 */78struct zonefs_zone_group {79	struct inode		*g_inode;80	unsigned int		g_nr_zones;81	struct zonefs_zone	*g_zones;82};83 84/*85 * In-memory inode data.86 */87struct zonefs_inode_info {88	struct inode		i_vnode;89 90	/*91	 * To serialise fully against both syscall and mmap based IO and92	 * sequential file truncation, two locks are used. For serializing93	 * zonefs_seq_file_truncate() against zonefs_iomap_begin(), that is,94	 * file truncate operations against block mapping, i_truncate_mutex is95	 * used. i_truncate_mutex also protects against concurrent accesses96	 * and changes to the inode private data, and in particular changes to97	 * a sequential file size on completion of direct IO writes.98	 * Serialization of mmap read IOs with truncate and syscall IO99	 * operations is done with invalidate_lock in addition to100	 * i_truncate_mutex.  Only zonefs_seq_file_truncate() takes both lock101	 * (invalidate_lock first, i_truncate_mutex second).102	 */103	struct mutex		i_truncate_mutex;104 105	/* guarded by i_truncate_mutex */106	unsigned int		i_wr_refcnt;107};108 109static inline struct zonefs_inode_info *ZONEFS_I(struct inode *inode)110{111	return container_of(inode, struct zonefs_inode_info, i_vnode);112}113 114static inline bool zonefs_zone_is_cnv(struct zonefs_zone *z)115{116	return z->z_flags & ZONEFS_ZONE_CNV;117}118 119static inline bool zonefs_zone_is_seq(struct zonefs_zone *z)120{121	return !zonefs_zone_is_cnv(z);122}123 124static inline struct zonefs_zone *zonefs_inode_zone(struct inode *inode)125{126	return inode->i_private;127}128 129static inline bool zonefs_inode_is_cnv(struct inode *inode)130{131	return zonefs_zone_is_cnv(zonefs_inode_zone(inode));132}133 134static inline bool zonefs_inode_is_seq(struct inode *inode)135{136	return zonefs_zone_is_seq(zonefs_inode_zone(inode));137}138 139/*140 * On-disk super block (block 0).141 */142#define ZONEFS_LABEL_LEN	64143#define ZONEFS_UUID_SIZE	16144#define ZONEFS_SUPER_SIZE	4096145 146struct zonefs_super {147 148	/* Magic number */149	__le32		s_magic;150 151	/* Checksum */152	__le32		s_crc;153 154	/* Volume label */155	char		s_label[ZONEFS_LABEL_LEN];156 157	/* 128-bit uuid */158	__u8		s_uuid[ZONEFS_UUID_SIZE];159 160	/* Features */161	__le64		s_features;162 163	/* UID/GID to use for files */164	__le32		s_uid;165	__le32		s_gid;166 167	/* File permissions */168	__le32		s_perm;169 170	/* Padding to ZONEFS_SUPER_SIZE bytes */171	__u8		s_reserved[3988];172 173} __packed;174 175/*176 * Feature flags: specified in the s_features field of the on-disk super177 * block struct zonefs_super and in-memory in the s_feartures field of178 * struct zonefs_sb_info.179 */180enum zonefs_features {181	/*182	 * Aggregate contiguous conventional zones into a single file.183	 */184	ZONEFS_F_AGGRCNV = 1ULL << 0,185	/*186	 * Use super block specified UID for files instead of default 0.187	 */188	ZONEFS_F_UID = 1ULL << 1,189	/*190	 * Use super block specified GID for files instead of default 0.191	 */192	ZONEFS_F_GID = 1ULL << 2,193	/*194	 * Use super block specified file permissions instead of default 640.195	 */196	ZONEFS_F_PERM = 1ULL << 3,197};198 199#define ZONEFS_F_DEFINED_FEATURES \200	(ZONEFS_F_AGGRCNV | ZONEFS_F_UID | ZONEFS_F_GID | ZONEFS_F_PERM)201 202/*203 * Mount options for zone write pointer error handling.204 */205#define ZONEFS_MNTOPT_ERRORS_RO		(1 << 0) /* Make zone file readonly */206#define ZONEFS_MNTOPT_ERRORS_ZRO	(1 << 1) /* Make zone file offline */207#define ZONEFS_MNTOPT_ERRORS_ZOL	(1 << 2) /* Make zone file offline */208#define ZONEFS_MNTOPT_ERRORS_REPAIR	(1 << 3) /* Remount read-only */209#define ZONEFS_MNTOPT_ERRORS_MASK	\210	(ZONEFS_MNTOPT_ERRORS_RO | ZONEFS_MNTOPT_ERRORS_ZRO | \211	 ZONEFS_MNTOPT_ERRORS_ZOL | ZONEFS_MNTOPT_ERRORS_REPAIR)212#define ZONEFS_MNTOPT_EXPLICIT_OPEN	(1 << 4) /* Explicit open/close of zones on open/close */213 214/*215 * In-memory Super block information.216 */217struct zonefs_sb_info {218 219	unsigned long		s_mount_opts;220 221	spinlock_t		s_lock;222 223	unsigned long long	s_features;224	kuid_t			s_uid;225	kgid_t			s_gid;226	umode_t			s_perm;227	uuid_t			s_uuid;228	unsigned int		s_zone_sectors_shift;229 230	struct zonefs_zone_group s_zgroup[ZONEFS_ZTYPE_MAX];231 232	loff_t			s_blocks;233	loff_t			s_used_blocks;234 235	unsigned int		s_max_wro_seq_files;236	atomic_t		s_wro_seq_files;237 238	unsigned int		s_max_active_seq_files;239	atomic_t		s_active_seq_files;240 241	bool			s_sysfs_registered;242	struct kobject		s_kobj;243	struct completion	s_kobj_unregister;244};245 246static inline struct zonefs_sb_info *ZONEFS_SB(struct super_block *sb)247{248	return sb->s_fs_info;249}250 251#define zonefs_info(sb, format, args...)	\252	pr_info("zonefs (%s): " format, sb->s_id, ## args)253#define zonefs_err(sb, format, args...)		\254	pr_err("zonefs (%s) ERROR: " format, sb->s_id, ## args)255#define zonefs_warn(sb, format, args...)	\256	pr_warn("zonefs (%s) WARNING: " format, sb->s_id, ## args)257 258/* In super.c */259void zonefs_inode_account_active(struct inode *inode);260int zonefs_inode_zone_mgmt(struct inode *inode, enum req_op op);261void zonefs_i_size_write(struct inode *inode, loff_t isize);262void zonefs_update_stats(struct inode *inode, loff_t new_isize);263void __zonefs_io_error(struct inode *inode, bool write);264 265static inline void zonefs_io_error(struct inode *inode, bool write)266{267	struct zonefs_inode_info *zi = ZONEFS_I(inode);268 269	mutex_lock(&zi->i_truncate_mutex);270	__zonefs_io_error(inode, write);271	mutex_unlock(&zi->i_truncate_mutex);272}273 274/* In super.c */275extern const struct inode_operations zonefs_dir_inode_operations;276extern const struct file_operations zonefs_dir_operations;277 278/* In file.c */279extern const struct address_space_operations zonefs_file_aops;280extern const struct file_operations zonefs_file_operations;281int zonefs_file_truncate(struct inode *inode, loff_t isize);282 283/* In sysfs.c */284int zonefs_sysfs_register(struct super_block *sb);285void zonefs_sysfs_unregister(struct super_block *sb);286int zonefs_sysfs_init(void);287void zonefs_sysfs_exit(void);288 289#endif290