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 fit 19 * the zone group directory names and a decimal zone number for file names. 20 * 16 characters is plenty. 21 */ 22 #define ZONEFS_NAME_MAX 16 23 24 /* 25 * Zone types: ZONEFS_ZTYPE_SEQ is used for all sequential zone types 26 * defined in linux/blkzoned.h, that is, BLK_ZONE_TYPE_SEQWRITE_REQ and 27 * BLK_ZONE_TYPE_SEQWRITE_PREF. 28 */ 29 enum zonefs_ztype { 30 ZONEFS_ZTYPE_CNV, 31 ZONEFS_ZTYPE_SEQ, 32 ZONEFS_ZTYPE_MAX, 33 }; 34 35 static 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 */ 52 struct 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 69 /* 70 * In memory zone group information: all zones of a group are exposed 71 * as files, one file per zone. 72 */ 73 struct zonefs_zone_group { 74 unsigned int g_nr_zones; 75 struct zonefs_zone *g_zones; 76 }; 77 78 /* 79 * In-memory inode data. 80 */ 81 struct zonefs_inode_info { 82 struct inode i_vnode; 83 84 /* 85 * To serialise fully against both syscall and mmap based IO and 86 * sequential file truncation, two locks are used. For serializing 87 * zonefs_seq_file_truncate() against zonefs_iomap_begin(), that is, 88 * file truncate operations against block mapping, i_truncate_mutex is 89 * used. i_truncate_mutex also protects against concurrent accesses 90 * and changes to the inode private data, and in particular changes to 91 * a sequential file size on completion of direct IO writes. 92 * Serialization of mmap read IOs with truncate and syscall IO 93 * operations is done with invalidate_lock in addition to 94 * i_truncate_mutex. Only zonefs_seq_file_truncate() takes both lock 95 * (invalidate_lock first, i_truncate_mutex second). 96 */ 97 struct mutex i_truncate_mutex; 98 99 /* guarded by i_truncate_mutex */ 100 unsigned int i_wr_refcnt; 101 }; 102 103 static inline struct zonefs_inode_info *ZONEFS_I(struct inode *inode) 104 { 105 return container_of(inode, struct zonefs_inode_info, i_vnode); 106 } 107 108 static inline bool zonefs_zone_is_cnv(struct zonefs_zone *z) 109 { 110 return z->z_flags & ZONEFS_ZONE_CNV; 111 } 112 113 static inline bool zonefs_zone_is_seq(struct zonefs_zone *z) 114 { 115 return !zonefs_zone_is_cnv(z); 116 } 117 118 static inline struct zonefs_zone *zonefs_inode_zone(struct inode *inode) 119 { 120 return inode->i_private; 121 } 122 123 static inline bool zonefs_inode_is_cnv(struct inode *inode) 124 { 125 return zonefs_zone_is_cnv(zonefs_inode_zone(inode)); 126 } 127 128 static inline bool zonefs_inode_is_seq(struct inode *inode) 129 { 130 return zonefs_zone_is_seq(zonefs_inode_zone(inode)); 131 } 132 133 /* 134 * On-disk super block (block 0). 135 */ 136 #define ZONEFS_LABEL_LEN 64 137 #define ZONEFS_UUID_SIZE 16 138 #define ZONEFS_SUPER_SIZE 4096 139 140 struct zonefs_super { 141 142 /* Magic number */ 143 __le32 s_magic; 144 145 /* Checksum */ 146 __le32 s_crc; 147 148 /* Volume label */ 149 char s_label[ZONEFS_LABEL_LEN]; 150 151 /* 128-bit uuid */ 152 __u8 s_uuid[ZONEFS_UUID_SIZE]; 153 154 /* Features */ 155 __le64 s_features; 156 157 /* UID/GID to use for files */ 158 __le32 s_uid; 159 __le32 s_gid; 160 161 /* File permissions */ 162 __le32 s_perm; 163 164 /* Padding to ZONEFS_SUPER_SIZE bytes */ 165 __u8 s_reserved[3988]; 166 167 } __packed; 168 169 /* 170 * Feature flags: specified in the s_features field of the on-disk super 171 * block struct zonefs_super and in-memory in the s_feartures field of 172 * struct zonefs_sb_info. 173 */ 174 enum zonefs_features { 175 /* 176 * Aggregate contiguous conventional zones into a single file. 177 */ 178 ZONEFS_F_AGGRCNV = 1ULL << 0, 179 /* 180 * Use super block specified UID for files instead of default 0. 181 */ 182 ZONEFS_F_UID = 1ULL << 1, 183 /* 184 * Use super block specified GID for files instead of default 0. 185 */ 186 ZONEFS_F_GID = 1ULL << 2, 187 /* 188 * Use super block specified file permissions instead of default 640. 189 */ 190 ZONEFS_F_PERM = 1ULL << 3, 191 }; 192 193 #define ZONEFS_F_DEFINED_FEATURES \ 194 (ZONEFS_F_AGGRCNV | ZONEFS_F_UID | ZONEFS_F_GID | ZONEFS_F_PERM) 195 196 /* 197 * Mount options for zone write pointer error handling. 198 */ 199 #define ZONEFS_MNTOPT_ERRORS_RO (1 << 0) /* Make zone file readonly */ 200 #define ZONEFS_MNTOPT_ERRORS_ZRO (1 << 1) /* Make zone file offline */ 201 #define ZONEFS_MNTOPT_ERRORS_ZOL (1 << 2) /* Make zone file offline */ 202 #define ZONEFS_MNTOPT_ERRORS_REPAIR (1 << 3) /* Remount read-only */ 203 #define ZONEFS_MNTOPT_ERRORS_MASK \ 204 (ZONEFS_MNTOPT_ERRORS_RO | ZONEFS_MNTOPT_ERRORS_ZRO | \ 205 ZONEFS_MNTOPT_ERRORS_ZOL | ZONEFS_MNTOPT_ERRORS_REPAIR) 206 #define ZONEFS_MNTOPT_EXPLICIT_OPEN (1 << 4) /* Explicit open/close of zones on open/close */ 207 208 /* 209 * In-memory Super block information. 210 */ 211 struct zonefs_sb_info { 212 213 unsigned long s_mount_opts; 214 215 spinlock_t s_lock; 216 217 unsigned long long s_features; 218 kuid_t s_uid; 219 kgid_t s_gid; 220 umode_t s_perm; 221 uuid_t s_uuid; 222 unsigned int s_zone_sectors_shift; 223 224 struct zonefs_zone_group s_zgroup[ZONEFS_ZTYPE_MAX]; 225 226 loff_t s_blocks; 227 loff_t s_used_blocks; 228 229 unsigned int s_max_wro_seq_files; 230 atomic_t s_wro_seq_files; 231 232 unsigned int s_max_active_seq_files; 233 atomic_t s_active_seq_files; 234 235 bool s_sysfs_registered; 236 struct kobject s_kobj; 237 struct completion s_kobj_unregister; 238 }; 239 240 static inline struct zonefs_sb_info *ZONEFS_SB(struct super_block *sb) 241 { 242 return sb->s_fs_info; 243 } 244 245 #define zonefs_info(sb, format, args...) \ 246 pr_info("zonefs (%s): " format, sb->s_id, ## args) 247 #define zonefs_err(sb, format, args...) \ 248 pr_err("zonefs (%s) ERROR: " format, sb->s_id, ## args) 249 #define zonefs_warn(sb, format, args...) \ 250 pr_warn("zonefs (%s) WARNING: " format, sb->s_id, ## args) 251 252 /* In super.c */ 253 void zonefs_inode_account_active(struct inode *inode); 254 int zonefs_inode_zone_mgmt(struct inode *inode, enum req_op op); 255 void zonefs_i_size_write(struct inode *inode, loff_t isize); 256 void zonefs_update_stats(struct inode *inode, loff_t new_isize); 257 void __zonefs_io_error(struct inode *inode, bool write); 258 259 static inline void zonefs_io_error(struct inode *inode, bool write) 260 { 261 struct zonefs_inode_info *zi = ZONEFS_I(inode); 262 263 mutex_lock(&zi->i_truncate_mutex); 264 __zonefs_io_error(inode, write); 265 mutex_unlock(&zi->i_truncate_mutex); 266 } 267 268 /* In file.c */ 269 extern const struct address_space_operations zonefs_file_aops; 270 extern const struct file_operations zonefs_file_operations; 271 int zonefs_file_truncate(struct inode *inode, loff_t isize); 272 273 /* In sysfs.c */ 274 int zonefs_sysfs_register(struct super_block *sb); 275 void zonefs_sysfs_unregister(struct super_block *sb); 276 int zonefs_sysfs_init(void); 277 void zonefs_sysfs_exit(void); 278 279 #endif 280