// SPDX-License-Identifier: GPL-2.0 /* * Simple file system for zoned block devices exposing zones as files. * * Copyright (C) 2019 Western Digital Corporation or its affiliates. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "zonefs.h" #define CREATE_TRACE_POINTS #include "trace.h" /* * Get the name of a zone group directory. */ static const char *zonefs_zgroup_name(enum zonefs_ztype ztype) { switch (ztype) { case ZONEFS_ZTYPE_CNV: return "cnv"; case ZONEFS_ZTYPE_SEQ: return "seq"; default: WARN_ON_ONCE(1); return "???"; } } /* * Manage the active zone count. */ static void zonefs_account_active(struct super_block *sb, struct zonefs_zone *z) { struct zonefs_sb_info *sbi = ZONEFS_SB(sb); if (zonefs_zone_is_cnv(z)) return; /* * For zones that transitioned to the offline or readonly condition, * we only need to clear the active state. */ if (z->z_flags & (ZONEFS_ZONE_OFFLINE | ZONEFS_ZONE_READONLY)) goto out; /* * If the zone is active, that is, if it is explicitly open or * partially written, check if it was already accounted as active. */ if ((z->z_flags & ZONEFS_ZONE_OPEN) || (z->z_wpoffset > 0 && z->z_wpoffset < z->z_capacity)) { if (!(z->z_flags & ZONEFS_ZONE_ACTIVE)) { z->z_flags |= ZONEFS_ZONE_ACTIVE; atomic_inc(&sbi->s_active_seq_files); } return; } out: /* The zone is not active. If it was, update the active count */ if (z->z_flags & ZONEFS_ZONE_ACTIVE) { z->z_flags &= ~ZONEFS_ZONE_ACTIVE; atomic_dec(&sbi->s_active_seq_files); } } /* * Manage the active zone count. Called with zi->i_truncate_mutex held. */ void zonefs_inode_account_active(struct inode *inode) { lockdep_assert_held(&ZONEFS_I(inode)->i_truncate_mutex); return zonefs_account_active(inode->i_sb, zonefs_inode_zone(inode)); } /* * Execute a zone management operation. */ static int zonefs_zone_mgmt(struct super_block *sb, struct zonefs_zone *z, enum req_op op) { int ret; /* * With ZNS drives, closing an explicitly open zone that has not been * written will change the zone state to "closed", that is, the zone * will remain active. Since this can then cause failure of explicit * open operation on other zones if the drive active zone resources * are exceeded, make sure that the zone does not remain active by * resetting it. */ if (op == REQ_OP_ZONE_CLOSE && !z->z_wpoffset) op = REQ_OP_ZONE_RESET; trace_zonefs_zone_mgmt(sb, z, op); ret = blkdev_zone_mgmt(sb->s_bdev, op, z->z_sector, z->z_size >> SECTOR_SHIFT, GFP_NOFS); if (ret) { zonefs_err(sb, "Zone management operation %s at %llu failed %d\n", blk_op_str(op), z->z_sector, ret); return ret; } return 0; } int zonefs_inode_zone_mgmt(struct inode *inode, enum req_op op) { lockdep_assert_held(&ZONEFS_I(inode)->i_truncate_mutex); return zonefs_zone_mgmt(inode->i_sb, zonefs_inode_zone(inode), op); } void zonefs_i_size_write(struct inode *inode, loff_t isize) { struct zonefs_zone *z = zonefs_inode_zone(inode); i_size_write(inode, isize); /* * A full zone is no longer open/active and does not need * explicit closing. */ if (isize >= z->z_capacity) { struct zonefs_sb_info *sbi = ZONEFS_SB(inode->i_sb); if (z->z_flags & ZONEFS_ZONE_ACTIVE) atomic_dec(&sbi->s_active_seq_files); z->z_flags &= ~(ZONEFS_ZONE_OPEN | ZONEFS_ZONE_ACTIVE); } } void zonefs_update_stats(struct inode *inode, loff_t new_isize) { struct super_block *sb = inode->i_sb; struct zonefs_sb_info *sbi = ZONEFS_SB(sb); loff_t old_isize = i_size_read(inode); loff_t nr_blocks; if (new_isize == old_isize) return; spin_lock(&sbi->s_lock); /* * This may be called for an update after an IO error. * So beware of the values seen. */ if (new_isize < old_isize) { nr_blocks = (old_isize - new_isize) >> sb->s_blocksize_bits; if (sbi->s_used_blocks > nr_blocks) sbi->s_used_blocks -= nr_blocks; else sbi->s_used_blocks = 0; } else { sbi->s_used_blocks += (new_isize - old_isize) >> sb->s_blocksize_bits; if (sbi->s_used_blocks > sbi->s_blocks) sbi->s_used_blocks = sbi->s_blocks; } spin_unlock(&sbi->s_lock); } /* * Check a zone condition. Return the amount of written (and still readable) * data in the zone. */ static loff_t zonefs_check_zone_condition(struct super_block *sb, struct zonefs_zone *z, struct blk_zone *zone) { switch (zone->cond) { case BLK_ZONE_COND_OFFLINE: zonefs_warn(sb, "Zone %llu: offline zone\n", z->z_sector); z->z_flags |= ZONEFS_ZONE_OFFLINE; return 0; case BLK_ZONE_COND_READONLY: /* * The write pointer of read-only zones is invalid, so we cannot * determine the zone wpoffset (inode size). We thus keep the * zone wpoffset as is, which leads to an empty file * (wpoffset == 0) on mount. For a runtime error, this keeps * the inode size as it was when last updated so that the user * can recover data. */ zonefs_warn(sb, "Zone %llu: read-only zone\n", z->z_sector); z->z_flags |= ZONEFS_ZONE_READONLY; if (zonefs_zone_is_cnv(z)) return z->z_capacity; return z->z_wpoffset; case BLK_ZONE_COND_FULL: /* The write pointer of full zones is invalid. */ return z->z_capacity; default: if (zonefs_zone_is_cnv(z)) return z->z_capacity; return (zone->wp - zone->start) << SECTOR_SHIFT; } } /* * Check a zone condition and adjust its inode access permissions for * offline and readonly zones. */ static void zonefs_inode_update_mode(struct inode *inode) { struct zonefs_zone *z = zonefs_inode_zone(inode); if (z->z_flags & ZONEFS_ZONE_OFFLINE) { /* Offline zones cannot be read nor written */ inode->i_flags |= S_IMMUTABLE; inode->i_mode &= ~0777; } else if (z->z_flags & ZONEFS_ZONE_READONLY) { /* Readonly zones cannot be written */ inode->i_flags |= S_IMMUTABLE; if (z->z_flags & ZONEFS_ZONE_INIT_MODE) inode->i_mode &= ~0777; else inode->i_mode &= ~0222; } z->z_flags &= ~ZONEFS_ZONE_INIT_MODE; z->z_mode = inode->i_mode; } static int zonefs_io_error_cb(struct blk_zone *zone, unsigned int idx, void *data) { struct blk_zone *z = data; *z = *zone; return 0; } static void zonefs_handle_io_error(struct inode *inode, struct blk_zone *zone, bool write) { struct zonefs_zone *z = zonefs_inode_zone(inode); struct super_block *sb = inode->i_sb; struct zonefs_sb_info *sbi = ZONEFS_SB(sb); loff_t isize, data_size; /* * Check the zone condition: if the zone is not "bad" (offline or * read-only), read errors are simply signaled to the IO issuer as long * as there is no inconsistency between the inode size and the amount of * data writen in the zone (data_size). */ data_size = zonefs_check_zone_condition(sb, z, zone); isize = i_size_read(inode); if (!(z->z_flags & (ZONEFS_ZONE_READONLY | ZONEFS_ZONE_OFFLINE)) && !write && isize == data_size) return; /* * At this point, we detected either a bad zone or an inconsistency * between the inode size and the amount of data written in the zone. * For the latter case, the cause may be a write IO error or an external * action on the device. Two error patterns exist: * 1) The inode size is lower than the amount of data in the zone: * a write operation partially failed and data was writen at the end * of the file. This can happen in the case of a large direct IO * needing several BIOs and/or write requests to be processed. * 2) The inode size is larger than the amount of data in the zone: * this can happen with a deferred write error with the use of the * device side write cache after getting successful write IO * completions. Other possibilities are (a) an external corruption, * e.g. an application reset the zone directly, or (b) the device * has a serious problem (e.g. firmware bug). * * In all cases, warn about inode size inconsistency and handle the * IO error according to the zone condition and to the mount options. */ if (isize != data_size) zonefs_warn(sb, "inode %lu: invalid size %lld (should be %lld)\n", inode->i_ino, isize, data_size); /* * First handle bad zones signaled by hardware. The mount options * errors=zone-ro and errors=zone-offline result in changing the * zone condition to read-only and offline respectively, as if the * condition was signaled by the hardware. */ if ((z->z_flags & ZONEFS_ZONE_OFFLINE) || (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_ZOL)) { zonefs_warn(sb, "inode %lu: read/write access disabled\n", inode->i_ino); if (!(z->z_flags & ZONEFS_ZONE_OFFLINE)) z->z_flags |= ZONEFS_ZONE_OFFLINE; zonefs_inode_update_mode(inode); data_size = 0; } else if ((z->z_flags & ZONEFS_ZONE_READONLY) || (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_ZRO)) { zonefs_warn(sb, "inode %lu: write access disabled\n", inode->i_ino); if (!(z->z_flags & ZONEFS_ZONE_READONLY)) z->z_flags |= ZONEFS_ZONE_READONLY; zonefs_inode_update_mode(inode); data_size = isize; } else if (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_RO && data_size > isize) { /* Do not expose garbage data */ data_size = isize; } /* * If the filesystem is mounted with the explicit-open mount option, we * need to clear the ZONEFS_ZONE_OPEN flag if the zone transitioned to * the read-only or offline condition, to avoid attempting an explicit * close of the zone when the inode file is closed. */ if ((sbi->s_mount_opts & ZONEFS_MNTOPT_EXPLICIT_OPEN) && (z->z_flags & (ZONEFS_ZONE_READONLY | ZONEFS_ZONE_OFFLINE))) z->z_flags &= ~ZONEFS_ZONE_OPEN; /* * If error=remount-ro was specified, any error result in remounting * the volume as read-only. */ if ((sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_RO) && !sb_rdonly(sb)) { zonefs_warn(sb, "remounting filesystem read-only\n"); sb->s_flags |= SB_RDONLY; } /* * Update block usage stats and the inode size to prevent access to * invalid data. */ zonefs_update_stats(inode, data_size); zonefs_i_size_write(inode, data_size); z->z_wpoffset = data_size; zonefs_inode_account_active(inode); } /* * When an file IO error occurs, check the file zone to see if there is a change * in the zone condition (e.g. offline or read-only). For a failed write to a * sequential zone, the zone write pointer position must also be checked to * eventually correct the file size and zonefs inode write pointer offset * (which can be out of sync with the drive due to partial write failures). */ void __zonefs_io_error(struct inode *inode, bool write) { struct zonefs_zone *z = zonefs_inode_zone(inode); struct super_block *sb = inode->i_sb; unsigned int noio_flag; struct blk_zone zone; int ret; /* * Conventional zone have no write pointer and cannot become read-only * or offline. So simply fake a report for a single or aggregated zone * and let zonefs_handle_io_error() correct the zone inode information * according to the mount options. */ if (!zonefs_zone_is_seq(z)) { zone.start = z->z_sector; zone.len = z->z_size >> SECTOR_SHIFT; zone.wp = zone.start + zone.len; zone.type = BLK_ZONE_TYPE_CONVENTIONAL; zone.cond = BLK_ZONE_COND_NOT_WP; zone.capacity = zone.len; goto handle_io_error; } /* * Memory allocations in blkdev_report_zones() can trigger a memory * reclaim which may in turn cause a recursion into zonefs as well as * struct request allocations for the same device. The former case may * end up in a deadlock on the inode truncate mutex, while the latter * may prevent IO forward progress. Executing the report zones under * the GFP_NOIO context avoids both problems. */ noio_flag = memalloc_noio_save(); ret = blkdev_report_zones(sb->s_bdev, z->z_sector, 1, zonefs_io_error_cb, &zone); memalloc_noio_restore(noio_flag); if (ret != 1) { zonefs_err(sb, "Get inode %lu zone information failed %d\n", inode->i_ino, ret); zonefs_warn(sb, "remounting filesystem read-only\n"); sb->s_flags |= SB_RDONLY; return; } handle_io_error: zonefs_handle_io_error(inode, &zone, write); } static struct kmem_cache *zonefs_inode_cachep; static struct inode *zonefs_alloc_inode(struct super_block *sb) { struct zonefs_inode_info *zi; zi = alloc_inode_sb(sb, zonefs_inode_cachep, GFP_KERNEL); if (!zi) return NULL; inode_init_once(&zi->i_vnode); mutex_init(&zi->i_truncate_mutex); zi->i_wr_refcnt = 0; return &zi->i_vnode; } static void zonefs_free_inode(struct inode *inode) { kmem_cache_free(zonefs_inode_cachep, ZONEFS_I(inode)); } /* * File system stat. */ static int zonefs_statfs(struct dentry *dentry, struct kstatfs *buf) { struct super_block *sb = dentry->d_sb; struct zonefs_sb_info *sbi = ZONEFS_SB(sb); enum zonefs_ztype t; buf->f_type = ZONEFS_MAGIC; buf->f_bsize = sb->s_blocksize; buf->f_namelen = ZONEFS_NAME_MAX; spin_lock(&sbi->s_lock); buf->f_blocks = sbi->s_blocks; if (WARN_ON(sbi->s_used_blocks > sbi->s_blocks)) buf->f_bfree = 0; else buf->f_bfree = buf->f_blocks - sbi->s_used_blocks; buf->f_bavail = buf->f_bfree; for (t = 0; t < ZONEFS_ZTYPE_MAX; t++) { if (sbi->s_zgroup[t].g_nr_zones) buf->f_files += sbi->s_zgroup[t].g_nr_zones + 1; } buf->f_ffree = 0; spin_unlock(&sbi->s_lock); buf->f_fsid = uuid_to_fsid(sbi->s_uuid.b); return 0; } enum { Opt_errors_ro, Opt_errors_zro, Opt_errors_zol, Opt_errors_repair, Opt_explicit_open, Opt_err, }; static const match_table_t tokens = { { Opt_errors_ro, "errors=remount-ro"}, { Opt_errors_zro, "errors=zone-ro"}, { Opt_errors_zol, "errors=zone-offline"}, { Opt_errors_repair, "errors=repair"}, { Opt_explicit_open, "explicit-open" }, { Opt_err, NULL} }; static int zonefs_parse_options(struct super_block *sb, char *options) { struct zonefs_sb_info *sbi = ZONEFS_SB(sb); substring_t args[MAX_OPT_ARGS]; char *p; if (!options) return 0; while ((p = strsep(&options, ",")) != NULL) { int token; if (!*p) continue; token = match_token(p, tokens, args); switch (token) { case Opt_errors_ro: sbi->s_mount_opts &= ~ZONEFS_MNTOPT_ERRORS_MASK; sbi->s_mount_opts |= ZONEFS_MNTOPT_ERRORS_RO; break; case Opt_errors_zro: sbi->s_mount_opts &= ~ZONEFS_MNTOPT_ERRORS_MASK; sbi->s_mount_opts |= ZONEFS_MNTOPT_ERRORS_ZRO; break; case Opt_errors_zol: sbi->s_mount_opts &= ~ZONEFS_MNTOPT_ERRORS_MASK; sbi->s_mount_opts |= ZONEFS_MNTOPT_ERRORS_ZOL; break; case Opt_errors_repair: sbi->s_mount_opts &= ~ZONEFS_MNTOPT_ERRORS_MASK; sbi->s_mount_opts |= ZONEFS_MNTOPT_ERRORS_REPAIR; break; case Opt_explicit_open: sbi->s_mount_opts |= ZONEFS_MNTOPT_EXPLICIT_OPEN; break; default: return -EINVAL; } } return 0; } static int zonefs_show_options(struct seq_file *seq, struct dentry *root) { struct zonefs_sb_info *sbi = ZONEFS_SB(root->d_sb); if (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_RO) seq_puts(seq, ",errors=remount-ro"); if (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_ZRO) seq_puts(seq, ",errors=zone-ro"); if (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_ZOL) seq_puts(seq, ",errors=zone-offline"); if (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_REPAIR) seq_puts(seq, ",errors=repair"); return 0; } static int zonefs_remount(struct super_block *sb, int *flags, char *data) { sync_filesystem(sb); return zonefs_parse_options(sb, data); } static int zonefs_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry, struct iattr *iattr) { struct inode *inode = d_inode(dentry); int ret; if (unlikely(IS_IMMUTABLE(inode))) return -EPERM; ret = setattr_prepare(&nop_mnt_idmap, dentry, iattr); if (ret) return ret; /* * Since files and directories cannot be created nor deleted, do not * allow setting any write attributes on the sub-directories grouping * files by zone type. */ if ((iattr->ia_valid & ATTR_MODE) && S_ISDIR(inode->i_mode) && (iattr->ia_mode & 0222)) return -EPERM; if (((iattr->ia_valid & ATTR_UID) && !uid_eq(iattr->ia_uid, inode->i_uid)) || ((iattr->ia_valid & ATTR_GID) && !gid_eq(iattr->ia_gid, inode->i_gid))) { ret = dquot_transfer(&nop_mnt_idmap, inode, iattr); if (ret) return ret; } if (iattr->ia_valid & ATTR_SIZE) { ret = zonefs_file_truncate(inode, iattr->ia_size); if (ret) return ret; } setattr_copy(&nop_mnt_idmap, inode, iattr); if (S_ISREG(inode->i_mode)) { struct zonefs_zone *z = zonefs_inode_zone(inode); z->z_mode = inode->i_mode; z->z_uid = inode->i_uid; z->z_gid = inode->i_gid; } return 0; } static const struct inode_operations zonefs_file_inode_operations = { .setattr = zonefs_inode_setattr, }; static long zonefs_fname_to_fno(const struct qstr *fname) { const char *name = fname->name; unsigned int len = fname->len; long fno = 0, shift = 1; const char *rname; char c = *name; unsigned int i; /* * File names are always a base-10 number string without any * leading 0s. */ if (!isdigit(c)) return -ENOENT; if (len > 1 && c == '0') return -ENOENT; if (len == 1) return c - '0'; for (i = 0, rname = name + len - 1; i < len; i++, rname--) { c = *rname; if (!isdigit(c)) return -ENOENT; fno += (c - '0') * shift; shift *= 10; } return fno; } static struct inode *zonefs_get_file_inode(struct inode *dir, struct dentry *dentry) { struct zonefs_zone_group *zgroup = dir->i_private; struct super_block *sb = dir->i_sb; struct zonefs_sb_info *sbi = ZONEFS_SB(sb); struct zonefs_zone *z; struct inode *inode; ino_t ino; long fno; /* Get the file number from the file name */ fno = zonefs_fname_to_fno(&dentry->d_name); if (fno < 0) return ERR_PTR(fno); if (!zgroup->g_nr_zones || fno >= zgroup->g_nr_zones) return ERR_PTR(-ENOENT); z = &zgroup->g_zones[fno]; ino = z->z_sector >> sbi->s_zone_sectors_shift; inode = iget_locked(sb, ino); if (!inode) return ERR_PTR(-ENOMEM); if (!(inode->i_state & I_NEW)) { WARN_ON_ONCE(inode->i_private != z); return inode; } inode->i_ino = ino; inode->i_mode = z->z_mode; inode_set_mtime_to_ts(inode, inode_set_atime_to_ts(inode, inode_set_ctime_to_ts(inode, inode_get_ctime(dir)))); inode->i_uid = z->z_uid; inode->i_gid = z->z_gid; inode->i_size = z->z_wpoffset; inode->i_blocks = z->z_capacity >> SECTOR_SHIFT; inode->i_private = z; inode->i_op = &zonefs_file_inode_operations; inode->i_fop = &zonefs_file_operations; inode->i_mapping->a_ops = &zonefs_file_aops; /* Update the inode access rights depending on the zone condition */ zonefs_inode_update_mode(inode); unlock_new_inode(inode); return inode; } static struct inode *zonefs_get_zgroup_inode(struct super_block *sb, enum zonefs_ztype ztype) { struct inode *root = d_inode(sb->s_root); struct zonefs_sb_info *sbi = ZONEFS_SB(sb); struct inode *inode; ino_t ino = bdev_nr_zones(sb->s_bdev) + ztype + 1; inode = iget_locked(sb, ino); if (!inode) return ERR_PTR(-ENOMEM); if (!(inode->i_state & I_NEW)) return inode; inode->i_ino = ino; inode_init_owner(&nop_mnt_idmap, inode, root, S_IFDIR | 0555); inode->i_size = sbi->s_zgroup[ztype].g_nr_zones; inode_set_mtime_to_ts(inode, inode_set_atime_to_ts(inode, inode_set_ctime_to_ts(inode, inode_get_ctime(root)))); inode->i_private = &sbi->s_zgroup[ztype]; set_nlink(inode, 2); inode->i_op = &zonefs_dir_inode_operations; inode->i_fop = &zonefs_dir_operations; unlock_new_inode(inode); return inode; } static struct inode *zonefs_get_dir_inode(struct inode *dir, struct dentry *dentry) { struct super_block *sb = dir->i_sb; struct zonefs_sb_info *sbi = ZONEFS_SB(sb); const char *name = dentry->d_name.name; enum zonefs_ztype ztype; /* * We only need to check for the "seq" directory and * the "cnv" directory if we have conventional zones. */ if (dentry->d_name.len != 3) return ERR_PTR(-ENOENT); for (ztype = 0; ztype < ZONEFS_ZTYPE_MAX; ztype++) { if (sbi->s_zgroup[ztype].g_nr_zones && memcmp(name, zonefs_zgroup_name(ztype), 3) == 0) break; } if (ztype == ZONEFS_ZTYPE_MAX) return ERR_PTR(-ENOENT); return zonefs_get_zgroup_inode(sb, ztype); } static struct dentry *zonefs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { struct inode *inode; if (dentry->d_name.len > ZONEFS_NAME_MAX) return ERR_PTR(-ENAMETOOLONG); if (dir == d_inode(dir->i_sb->s_root)) inode = zonefs_get_dir_inode(dir, dentry); else inode = zonefs_get_file_inode(dir, dentry); return d_splice_alias(inode, dentry); } static int zonefs_readdir_root(struct file *file, struct dir_context *ctx) { struct inode *inode = file_inode(file); struct super_block *sb = inode->i_sb; struct zonefs_sb_info *sbi = ZONEFS_SB(sb); enum zonefs_ztype ztype = ZONEFS_ZTYPE_CNV; ino_t base_ino = bdev_nr_zones(sb->s_bdev) + 1; if (ctx->pos >= inode->i_size) return 0; if (!dir_emit_dots(file, ctx)) return 0; if (ctx->pos == 2) { if (!sbi->s_zgroup[ZONEFS_ZTYPE_CNV].g_nr_zones) ztype = ZONEFS_ZTYPE_SEQ; if (!dir_emit(ctx, zonefs_zgroup_name(ztype), 3, base_ino + ztype, DT_DIR)) return 0; ctx->pos++; } if (ctx->pos == 3 && ztype != ZONEFS_ZTYPE_SEQ) { ztype = ZONEFS_ZTYPE_SEQ; if (!dir_emit(ctx, zonefs_zgroup_name(ztype), 3, base_ino + ztype, DT_DIR)) return 0; ctx->pos++; } return 0; } static int zonefs_readdir_zgroup(struct file *file, struct dir_context *ctx) { struct inode *inode = file_inode(file); struct zonefs_zone_group *zgroup = inode->i_private; struct super_block *sb = inode->i_sb; struct zonefs_sb_info *sbi = ZONEFS_SB(sb); struct zonefs_zone *z; int fname_len; char *fname; ino_t ino; int f; /* * The size of zone group directories is equal to the number * of zone files in the group and does note include the "." and * ".." entries. Hence the "+ 2" here. */ if (ctx->pos >= inode->i_size + 2) return 0; if (!dir_emit_dots(file, ctx)) return 0; fname = kmalloc(ZONEFS_NAME_MAX, GFP_KERNEL); if (!fname) return -ENOMEM; for (f = ctx->pos - 2; f < zgroup->g_nr_zones; f++) { z = &zgroup->g_zones[f]; ino = z->z_sector >> sbi->s_zone_sectors_shift; fname_len = snprintf(fname, ZONEFS_NAME_MAX - 1, "%u", f); if (!dir_emit(ctx, fname, fname_len, ino, DT_REG)) break; ctx->pos++; } kfree(fname); return 0; } static int zonefs_readdir(struct file *file, struct dir_context *ctx) { struct inode *inode = file_inode(file); if (inode == d_inode(inode->i_sb->s_root)) return zonefs_readdir_root(file, ctx); return zonefs_readdir_zgroup(file, ctx); } const struct inode_operations zonefs_dir_inode_operations = { .lookup = zonefs_lookup, .setattr = zonefs_inode_setattr, }; const struct file_operations zonefs_dir_operations = { .llseek = generic_file_llseek, .read = generic_read_dir, .iterate_shared = zonefs_readdir, }; struct zonefs_zone_data { struct super_block *sb; unsigned int nr_zones[ZONEFS_ZTYPE_MAX]; sector_t cnv_zone_start; struct blk_zone *zones; }; static int zonefs_get_zone_info_cb(struct blk_zone *zone, unsigned int idx, void *data) { struct zonefs_zone_data *zd = data; struct super_block *sb = zd->sb; struct zonefs_sb_info *sbi = ZONEFS_SB(sb); /* * We do not care about the first zone: it contains the super block * and not exposed as a file. */ if (!idx) return 0; /* * Count the number of zones that will be exposed as files. * For sequential zones, we always have as many files as zones. * FOr conventional zones, the number of files depends on if we have * conventional zones aggregation enabled. */ switch (zone->type) { case BLK_ZONE_TYPE_CONVENTIONAL: if (sbi->s_features & ZONEFS_F_AGGRCNV) { /* One file per set of contiguous conventional zones */ if (!(sbi->s_zgroup[ZONEFS_ZTYPE_CNV].g_nr_zones) || zone->start != zd->cnv_zone_start) sbi->s_zgroup[ZONEFS_ZTYPE_CNV].g_nr_zones++; zd->cnv_zone_start = zone->start + zone->len; } else { /* One file per zone */ sbi->s_zgroup[ZONEFS_ZTYPE_CNV].g_nr_zones++; } break; case BLK_ZONE_TYPE_SEQWRITE_REQ: case BLK_ZONE_TYPE_SEQWRITE_PREF: sbi->s_zgroup[ZONEFS_ZTYPE_SEQ].g_nr_zones++; break; default: zonefs_err(zd->sb, "Unsupported zone type 0x%x\n", zone->type); return -EIO; } memcpy(&zd->zones[idx], zone, sizeof(struct blk_zone)); return 0; } static int zonefs_get_zone_info(struct zonefs_zone_data *zd) { struct block_device *bdev = zd->sb->s_bdev; int ret; zd->zones = kvcalloc(bdev_nr_zones(bdev), sizeof(struct blk_zone), GFP_KERNEL); if (!zd->zones) return -ENOMEM; /* Get zones information from the device */ ret = blkdev_report_zones(bdev, 0, BLK_ALL_ZONES, zonefs_get_zone_info_cb, zd); if (ret < 0) { zonefs_err(zd->sb, "Zone report failed %d\n", ret); return ret; } if (ret != bdev_nr_zones(bdev)) { zonefs_err(zd->sb, "Invalid zone report (%d/%u zones)\n", ret, bdev_nr_zones(bdev)); return -EIO; } return 0; } static inline void zonefs_free_zone_info(struct zonefs_zone_data *zd) { kvfree(zd->zones); } /* * Create a zone group and populate it with zone files. */ static int zonefs_init_zgroup(struct super_block *sb, struct zonefs_zone_data *zd, enum zonefs_ztype ztype) { struct zonefs_sb_info *sbi = ZONEFS_SB(sb); struct zonefs_zone_group *zgroup = &sbi->s_zgroup[ztype]; struct blk_zone *zone, *next, *end; struct zonefs_zone *z; unsigned int n = 0; int ret; /* Allocate the zone group. If it is empty, we have nothing to do. */ if (!zgroup->g_nr_zones) return 0; zgroup->g_zones = kvcalloc(zgroup->g_nr_zones, sizeof(struct zonefs_zone), GFP_KERNEL); if (!zgroup->g_zones) return -ENOMEM; /* * Initialize the zone groups using the device zone information. * We always skip the first zone as it contains the super block * and is not use to back a file. */ end = zd->zones + bdev_nr_zones(sb->s_bdev); for (zone = &zd->zones[1]; zone < end; zone = next) { next = zone + 1; if (zonefs_zone_type(zone) != ztype) continue; if (WARN_ON_ONCE(n >= zgroup->g_nr_zones)) return -EINVAL; /* * For conventional zones, contiguous zones can be aggregated * together to form larger files. Note that this overwrites the * length of the first zone of the set of contiguous zones * aggregated together. If one offline or read-only zone is * found, assume that all zones aggregated have the same * condition. */ if (ztype == ZONEFS_ZTYPE_CNV && (sbi->s_features & ZONEFS_F_AGGRCNV)) { for (; next < end; next++) { if (zonefs_zone_type(next) != ztype) break; zone->len += next->len; zone->capacity += next->capacity; if (next->cond == BLK_ZONE_COND_READONLY && zone->cond != BLK_ZONE_COND_OFFLINE) zone->cond = BLK_ZONE_COND_READONLY; else if (next->cond == BLK_ZONE_COND_OFFLINE) zone->cond = BLK_ZONE_COND_OFFLINE; } } z = &zgroup->g_zones[n]; if (ztype == ZONEFS_ZTYPE_CNV) z->z_flags |= ZONEFS_ZONE_CNV; z->z_sector = zone->start; z->z_size = zone->len << SECTOR_SHIFT; if (z->z_size > bdev_zone_sectors(sb->s_bdev) << SECTOR_SHIFT && !(sbi->s_features & ZONEFS_F_AGGRCNV)) { zonefs_err(sb, "Invalid zone size %llu (device zone sectors %llu)\n", z->z_size, bdev_zone_sectors(sb->s_bdev) << SECTOR_SHIFT); return -EINVAL; } z->z_capacity = min_t(loff_t, MAX_LFS_FILESIZE, zone->capacity << SECTOR_SHIFT); z->z_wpoffset = zonefs_check_zone_condition(sb, z, zone); z->z_mode = S_IFREG | sbi->s_perm; z->z_uid = sbi->s_uid; z->z_gid = sbi->s_gid; /* * Let zonefs_inode_update_mode() know that we will need * special initialization of the inode mode the first time * it is accessed. */ z->z_flags |= ZONEFS_ZONE_INIT_MODE; sb->s_maxbytes = max(z->z_capacity, sb->s_maxbytes); sbi->s_blocks += z->z_capacity >> sb->s_blocksize_bits; sbi->s_used_blocks += z->z_wpoffset >> sb->s_blocksize_bits; /* * For sequential zones, make sure that any open zone is closed * first to ensure that the initial number of open zones is 0, * in sync with the open zone accounting done when the mount * option ZONEFS_MNTOPT_EXPLICIT_OPEN is used. */ if (ztype == ZONEFS_ZTYPE_SEQ && (zone->cond == BLK_ZONE_COND_IMP_OPEN || zone->cond == BLK_ZONE_COND_EXP_OPEN)) { ret = zonefs_zone_mgmt(sb, z, REQ_OP_ZONE_CLOSE); if (ret) return ret; } zonefs_account_active(sb, z); n++; } if (WARN_ON_ONCE(n != zgroup->g_nr_zones)) return -EINVAL; zonefs_info(sb, "Zone group \"%s\" has %u file%s\n", zonefs_zgroup_name(ztype), zgroup->g_nr_zones, zgroup->g_nr_zones > 1 ? "s" : ""); return 0; } static void zonefs_free_zgroups(struct super_block *sb) { struct zonefs_sb_info *sbi = ZONEFS_SB(sb); enum zonefs_ztype ztype; if (!sbi) return; for (ztype = 0; ztype < ZONEFS_ZTYPE_MAX; ztype++) { kvfree(sbi->s_zgroup[ztype].g_zones); sbi->s_zgroup[ztype].g_zones = NULL; } } /* * Create a zone group and populate it with zone files. */ static int zonefs_init_zgroups(struct super_block *sb) { struct zonefs_zone_data zd; enum zonefs_ztype ztype; int ret; /* First get the device zone information */ memset(&zd, 0, sizeof(struct zonefs_zone_data)); zd.sb = sb; ret = zonefs_get_zone_info(&zd); if (ret) goto cleanup; /* Allocate and initialize the zone groups */ for (ztype = 0; ztype < ZONEFS_ZTYPE_MAX; ztype++) { ret = zonefs_init_zgroup(sb, &zd, ztype); if (ret) { zonefs_info(sb, "Zone group \"%s\" initialization failed\n", zonefs_zgroup_name(ztype)); break; } } cleanup: zonefs_free_zone_info(&zd); if (ret) zonefs_free_zgroups(sb); return ret; } /* * Read super block information from the device. */ static int zonefs_read_super(struct super_block *sb) { struct zonefs_sb_info *sbi = ZONEFS_SB(sb); struct zonefs_super *super; u32 crc, stored_crc; struct page *page; struct bio_vec bio_vec; struct bio bio; int ret; page = alloc_page(GFP_KERNEL); if (!page) return -ENOMEM; bio_init(&bio, sb->s_bdev, &bio_vec, 1, REQ_OP_READ); bio.bi_iter.bi_sector = 0; __bio_add_page(&bio, page, PAGE_SIZE, 0); ret = submit_bio_wait(&bio); if (ret) goto free_page; super = page_address(page); ret = -EINVAL; if (le32_to_cpu(super->s_magic) != ZONEFS_MAGIC) goto free_page; stored_crc = le32_to_cpu(super->s_crc); super->s_crc = 0; crc = crc32(~0U, (unsigned char *)super, sizeof(struct zonefs_super)); if (crc != stored_crc) { zonefs_err(sb, "Invalid checksum (Expected 0x%08x, got 0x%08x)", crc, stored_crc); goto free_page; } sbi->s_features = le64_to_cpu(super->s_features); if (sbi->s_features & ~ZONEFS_F_DEFINED_FEATURES) { zonefs_err(sb, "Unknown features set 0x%llx\n", sbi->s_features); goto free_page; } if (sbi->s_features & ZONEFS_F_UID) { sbi->s_uid = make_kuid(current_user_ns(), le32_to_cpu(super->s_uid)); if (!uid_valid(sbi->s_uid)) { zonefs_err(sb, "Invalid UID feature\n"); goto free_page; } } if (sbi->s_features & ZONEFS_F_GID) { sbi->s_gid = make_kgid(current_user_ns(), le32_to_cpu(super->s_gid)); if (!gid_valid(sbi->s_gid)) { zonefs_err(sb, "Invalid GID feature\n"); goto free_page; } } if (sbi->s_features & ZONEFS_F_PERM) sbi->s_perm = le32_to_cpu(super->s_perm); if (memchr_inv(super->s_reserved, 0, sizeof(super->s_reserved))) { zonefs_err(sb, "Reserved area is being used\n"); goto free_page; } import_uuid(&sbi->s_uuid, super->s_uuid); ret = 0; free_page: __free_page(page); return ret; } static const struct super_operations zonefs_sops = { .alloc_inode = zonefs_alloc_inode, .free_inode = zonefs_free_inode, .statfs = zonefs_statfs, .remount_fs = zonefs_remount, .show_options = zonefs_show_options, }; static int zonefs_get_zgroup_inodes(struct super_block *sb) { struct zonefs_sb_info *sbi = ZONEFS_SB(sb); struct inode *dir_inode; enum zonefs_ztype ztype; for (ztype = 0; ztype < ZONEFS_ZTYPE_MAX; ztype++) { if (!sbi->s_zgroup[ztype].g_nr_zones) continue; dir_inode = zonefs_get_zgroup_inode(sb, ztype); if (IS_ERR(dir_inode)) return PTR_ERR(dir_inode); sbi->s_zgroup[ztype].g_inode = dir_inode; } return 0; } static void zonefs_release_zgroup_inodes(struct super_block *sb) { struct zonefs_sb_info *sbi = ZONEFS_SB(sb); enum zonefs_ztype ztype; if (!sbi) return; for (ztype = 0; ztype < ZONEFS_ZTYPE_MAX; ztype++) { if (sbi->s_zgroup[ztype].g_inode) { iput(sbi->s_zgroup[ztype].g_inode); sbi->s_zgroup[ztype].g_inode = NULL; } } } /* * Check that the device is zoned. If it is, get the list of zones and create * sub-directories and files according to the device zone configuration and * format options. */ static int zonefs_fill_super(struct super_block *sb, void *data, int silent) { struct zonefs_sb_info *sbi; struct inode *inode; enum zonefs_ztype ztype; int ret; if (!bdev_is_zoned(sb->s_bdev)) { zonefs_err(sb, "Not a zoned block device\n"); return -EINVAL; } /* * Initialize super block information: the maximum file size is updated * when the zone files are created so that the format option * ZONEFS_F_AGGRCNV which increases the maximum file size of a file * beyond the zone size is taken into account. */ sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); if (!sbi) return -ENOMEM; spin_lock_init(&sbi->s_lock); sb->s_fs_info = sbi; sb->s_magic = ZONEFS_MAGIC; sb->s_maxbytes = 0; sb->s_op = &zonefs_sops; sb->s_time_gran = 1; /* * The block size is set to the device zone write granularity to ensure * that write operations are always aligned according to the device * interface constraints. */ sb_set_blocksize(sb, bdev_zone_write_granularity(sb->s_bdev)); sbi->s_zone_sectors_shift = ilog2(bdev_zone_sectors(sb->s_bdev)); sbi->s_uid = GLOBAL_ROOT_UID; sbi->s_gid = GLOBAL_ROOT_GID; sbi->s_perm = 0640; sbi->s_mount_opts = ZONEFS_MNTOPT_ERRORS_RO; atomic_set(&sbi->s_wro_seq_files, 0); sbi->s_max_wro_seq_files = bdev_max_open_zones(sb->s_bdev); atomic_set(&sbi->s_active_seq_files, 0); sbi->s_max_active_seq_files = bdev_max_active_zones(sb->s_bdev); ret = zonefs_read_super(sb); if (ret) return ret; ret = zonefs_parse_options(sb, data); if (ret) return ret; zonefs_info(sb, "Mounting %u zones", bdev_nr_zones(sb->s_bdev)); if (!sbi->s_max_wro_seq_files && !sbi->s_max_active_seq_files && sbi->s_mount_opts & ZONEFS_MNTOPT_EXPLICIT_OPEN) { zonefs_info(sb, "No open and active zone limits. Ignoring explicit_open mount option\n"); sbi->s_mount_opts &= ~ZONEFS_MNTOPT_EXPLICIT_OPEN; } /* Initialize the zone groups */ ret = zonefs_init_zgroups(sb); if (ret) goto cleanup; /* Create the root directory inode */ ret = -ENOMEM; inode = new_inode(sb); if (!inode) goto cleanup; inode->i_ino = bdev_nr_zones(sb->s_bdev); inode->i_mode = S_IFDIR | 0555; simple_inode_init_ts(inode); inode->i_op = &zonefs_dir_inode_operations; inode->i_fop = &zonefs_dir_operations; inode->i_size = 2; set_nlink(inode, 2); for (ztype = 0; ztype < ZONEFS_ZTYPE_MAX; ztype++) { if (sbi->s_zgroup[ztype].g_nr_zones) { inc_nlink(inode); inode->i_size++; } } sb->s_root = d_make_root(inode); if (!sb->s_root) goto cleanup; /* * Take a reference on the zone groups directory inodes * to keep them in the inode cache. */ ret = zonefs_get_zgroup_inodes(sb); if (ret) goto cleanup; ret = zonefs_sysfs_register(sb); if (ret) goto cleanup; return 0; cleanup: zonefs_release_zgroup_inodes(sb); zonefs_free_zgroups(sb); return ret; } static struct dentry *zonefs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) { return mount_bdev(fs_type, flags, dev_name, data, zonefs_fill_super); } static void zonefs_kill_super(struct super_block *sb) { struct zonefs_sb_info *sbi = ZONEFS_SB(sb); /* Release the reference on the zone group directory inodes */ zonefs_release_zgroup_inodes(sb); kill_block_super(sb); zonefs_sysfs_unregister(sb); zonefs_free_zgroups(sb); kfree(sbi); } /* * File system definition and registration. */ static struct file_system_type zonefs_type = { .owner = THIS_MODULE, .name = "zonefs", .mount = zonefs_mount, .kill_sb = zonefs_kill_super, .fs_flags = FS_REQUIRES_DEV, }; static int __init zonefs_init_inodecache(void) { zonefs_inode_cachep = kmem_cache_create("zonefs_inode_cache", sizeof(struct zonefs_inode_info), 0, (SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | SLAB_ACCOUNT), NULL); if (zonefs_inode_cachep == NULL) return -ENOMEM; return 0; } static void zonefs_destroy_inodecache(void) { /* * Make sure all delayed rcu free inodes are flushed before we * destroy the inode cache. */ rcu_barrier(); kmem_cache_destroy(zonefs_inode_cachep); } static int __init zonefs_init(void) { int ret; BUILD_BUG_ON(sizeof(struct zonefs_super) != ZONEFS_SUPER_SIZE); ret = zonefs_init_inodecache(); if (ret) return ret; ret = zonefs_sysfs_init(); if (ret) goto destroy_inodecache; ret = register_filesystem(&zonefs_type); if (ret) goto sysfs_exit; return 0; sysfs_exit: zonefs_sysfs_exit(); destroy_inodecache: zonefs_destroy_inodecache(); return ret; } static void __exit zonefs_exit(void) { unregister_filesystem(&zonefs_type); zonefs_sysfs_exit(); zonefs_destroy_inodecache(); } MODULE_AUTHOR("Damien Le Moal"); MODULE_DESCRIPTION("Zone file system for zoned block devices"); MODULE_LICENSE("GPL"); MODULE_ALIAS_FS("zonefs"); module_init(zonefs_init); module_exit(zonefs_exit);