// 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" static inline int zonefs_zone_mgmt(struct inode *inode, enum req_opf op) { struct zonefs_inode_info *zi = ZONEFS_I(inode); int ret; lockdep_assert_held(&zi->i_truncate_mutex); /* * 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 && !zi->i_wpoffset) op = REQ_OP_ZONE_RESET; trace_zonefs_zone_mgmt(inode, op); ret = blkdev_zone_mgmt(inode->i_sb->s_bdev, op, zi->i_zsector, zi->i_zone_size >> SECTOR_SHIFT, GFP_NOFS); if (ret) { zonefs_err(inode->i_sb, "Zone management operation %s at %llu failed %d\n", blk_op_str(op), zi->i_zsector, ret); return ret; } return 0; } static inline void zonefs_i_size_write(struct inode *inode, loff_t isize) { struct zonefs_inode_info *zi = ZONEFS_I(inode); i_size_write(inode, isize); /* * A full zone is no longer open/active and does not need * explicit closing. */ if (isize >= zi->i_max_size) zi->i_flags &= ~ZONEFS_ZONE_OPEN; } static int zonefs_read_iomap_begin(struct inode *inode, loff_t offset, loff_t length, unsigned int flags, struct iomap *iomap, struct iomap *srcmap) { struct zonefs_inode_info *zi = ZONEFS_I(inode); struct super_block *sb = inode->i_sb; loff_t isize; /* * All blocks are always mapped below EOF. If reading past EOF, * act as if there is a hole up to the file maximum size. */ mutex_lock(&zi->i_truncate_mutex); iomap->bdev = inode->i_sb->s_bdev; iomap->offset = ALIGN_DOWN(offset, sb->s_blocksize); isize = i_size_read(inode); if (iomap->offset >= isize) { iomap->type = IOMAP_HOLE; iomap->addr = IOMAP_NULL_ADDR; iomap->length = length; } else { iomap->type = IOMAP_MAPPED; iomap->addr = (zi->i_zsector << SECTOR_SHIFT) + iomap->offset; iomap->length = isize - iomap->offset; } mutex_unlock(&zi->i_truncate_mutex); trace_zonefs_iomap_begin(inode, iomap); return 0; } static const struct iomap_ops zonefs_read_iomap_ops = { .iomap_begin = zonefs_read_iomap_begin, }; static int zonefs_write_iomap_begin(struct inode *inode, loff_t offset, loff_t length, unsigned int flags, struct iomap *iomap, struct iomap *srcmap) { struct zonefs_inode_info *zi = ZONEFS_I(inode); struct super_block *sb = inode->i_sb; loff_t isize; /* All write I/Os should always be within the file maximum size */ if (WARN_ON_ONCE(offset + length > zi->i_max_size)) return -EIO; /* * Sequential zones can only accept direct writes. This is already * checked when writes are issued, so warn if we see a page writeback * operation. */ if (WARN_ON_ONCE(zi->i_ztype == ZONEFS_ZTYPE_SEQ && !(flags & IOMAP_DIRECT))) return -EIO; /* * For conventional zones, all blocks are always mapped. For sequential * zones, all blocks after always mapped below the inode size (zone * write pointer) and unwriten beyond. */ mutex_lock(&zi->i_truncate_mutex); iomap->bdev = inode->i_sb->s_bdev; iomap->offset = ALIGN_DOWN(offset, sb->s_blocksize); iomap->addr = (zi->i_zsector << SECTOR_SHIFT) + iomap->offset; isize = i_size_read(inode); if (iomap->offset >= isize) { iomap->type = IOMAP_UNWRITTEN; iomap->length = zi->i_max_size - iomap->offset; } else { iomap->type = IOMAP_MAPPED; iomap->length = isize - iomap->offset; } mutex_unlock(&zi->i_truncate_mutex); trace_zonefs_iomap_begin(inode, iomap); return 0; } static const struct iomap_ops zonefs_write_iomap_ops = { .iomap_begin = zonefs_write_iomap_begin, }; static int zonefs_readpage(struct file *unused, struct page *page) { return iomap_readpage(page, &zonefs_read_iomap_ops); } static void zonefs_readahead(struct readahead_control *rac) { iomap_readahead(rac, &zonefs_read_iomap_ops); } /* * Map blocks for page writeback. This is used only on conventional zone files, * which implies that the page range can only be within the fixed inode size. */ static int zonefs_write_map_blocks(struct iomap_writepage_ctx *wpc, struct inode *inode, loff_t offset) { struct zonefs_inode_info *zi = ZONEFS_I(inode); if (WARN_ON_ONCE(zi->i_ztype != ZONEFS_ZTYPE_CNV)) return -EIO; if (WARN_ON_ONCE(offset >= i_size_read(inode))) return -EIO; /* If the mapping is already OK, nothing needs to be done */ if (offset >= wpc->iomap.offset && offset < wpc->iomap.offset + wpc->iomap.length) return 0; return zonefs_write_iomap_begin(inode, offset, zi->i_max_size - offset, IOMAP_WRITE, &wpc->iomap, NULL); } static const struct iomap_writeback_ops zonefs_writeback_ops = { .map_blocks = zonefs_write_map_blocks, }; static int zonefs_writepage(struct page *page, struct writeback_control *wbc) { struct iomap_writepage_ctx wpc = { }; return iomap_writepage(page, wbc, &wpc, &zonefs_writeback_ops); } static int zonefs_writepages(struct address_space *mapping, struct writeback_control *wbc) { struct iomap_writepage_ctx wpc = { }; return iomap_writepages(mapping, wbc, &wpc, &zonefs_writeback_ops); } static int zonefs_swap_activate(struct swap_info_struct *sis, struct file *swap_file, sector_t *span) { struct inode *inode = file_inode(swap_file); struct zonefs_inode_info *zi = ZONEFS_I(inode); if (zi->i_ztype != ZONEFS_ZTYPE_CNV) { zonefs_err(inode->i_sb, "swap file: not a conventional zone file\n"); return -EINVAL; } return iomap_swapfile_activate(sis, swap_file, span, &zonefs_read_iomap_ops); } static const struct address_space_operations zonefs_file_aops = { .readpage = zonefs_readpage, .readahead = zonefs_readahead, .writepage = zonefs_writepage, .writepages = zonefs_writepages, .set_page_dirty = __set_page_dirty_nobuffers, .releasepage = iomap_releasepage, .invalidatepage = iomap_invalidatepage, .migratepage = iomap_migrate_page, .is_partially_uptodate = iomap_is_partially_uptodate, .error_remove_page = generic_error_remove_page, .direct_IO = noop_direct_IO, .swap_activate = zonefs_swap_activate, }; static 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 and adjust its file inode access permissions for * offline and readonly zones. Return the inode size corresponding to the * amount of readable data in the zone. */ static loff_t zonefs_check_zone_condition(struct inode *inode, struct blk_zone *zone, bool warn, bool mount) { struct zonefs_inode_info *zi = ZONEFS_I(inode); switch (zone->cond) { case BLK_ZONE_COND_OFFLINE: /* * Dead zone: make the inode immutable, disable all accesses * and set the file size to 0 (zone wp set to zone start). */ if (warn) zonefs_warn(inode->i_sb, "inode %lu: offline zone\n", inode->i_ino); inode->i_flags |= S_IMMUTABLE; inode->i_mode &= ~0777; zone->wp = zone->start; return 0; case BLK_ZONE_COND_READONLY: /* * The write pointer of read-only zones is invalid. If such a * zone is found during mount, the file size cannot be retrieved * so we treat the zone as offline (mount == true case). * Otherwise, keep the file size as it was when last updated * so that the user can recover data. In both cases, writes are * always disabled for the zone. */ if (warn) zonefs_warn(inode->i_sb, "inode %lu: read-only zone\n", inode->i_ino); inode->i_flags |= S_IMMUTABLE; if (mount) { zone->cond = BLK_ZONE_COND_OFFLINE; inode->i_mode &= ~0777; zone->wp = zone->start; return 0; } inode->i_mode &= ~0222; return i_size_read(inode); case BLK_ZONE_COND_FULL: /* The write pointer of full zones is invalid. */ return zi->i_max_size; default: if (zi->i_ztype == ZONEFS_ZTYPE_CNV) return zi->i_max_size; return (zone->wp - zone->start) << SECTOR_SHIFT; } } struct zonefs_ioerr_data { struct inode *inode; bool write; }; static int zonefs_io_error_cb(struct blk_zone *zone, unsigned int idx, void *data) { struct zonefs_ioerr_data *err = data; struct inode *inode = err->inode; struct zonefs_inode_info *zi = ZONEFS_I(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(inode, zone, true, false); isize = i_size_read(inode); if (zone->cond != BLK_ZONE_COND_OFFLINE && zone->cond != BLK_ZONE_COND_READONLY && !err->write && isize == data_size) return 0; /* * 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 (zi->i_ztype == ZONEFS_ZTYPE_SEQ && 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 (zone->cond == BLK_ZONE_COND_OFFLINE || sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_ZOL) { zonefs_warn(sb, "inode %lu: read/write access disabled\n", inode->i_ino); if (zone->cond != BLK_ZONE_COND_OFFLINE) { zone->cond = BLK_ZONE_COND_OFFLINE; data_size = zonefs_check_zone_condition(inode, zone, false, false); } } else if (zone->cond == BLK_ZONE_COND_READONLY || sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_ZRO) { zonefs_warn(sb, "inode %lu: write access disabled\n", inode->i_ino); if (zone->cond != BLK_ZONE_COND_READONLY) { zone->cond = BLK_ZONE_COND_READONLY; data_size = zonefs_check_zone_condition(inode, zone, false, false); } } 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) && (zone->cond == BLK_ZONE_COND_OFFLINE || zone->cond == BLK_ZONE_COND_READONLY)) zi->i_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); zi->i_wpoffset = data_size; return 0; } /* * 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). */ static void __zonefs_io_error(struct inode *inode, bool write) { struct zonefs_inode_info *zi = ZONEFS_I(inode); struct super_block *sb = inode->i_sb; struct zonefs_sb_info *sbi = ZONEFS_SB(sb); unsigned int noio_flag; unsigned int nr_zones = 1; struct zonefs_ioerr_data err = { .inode = inode, .write = write, }; int ret; /* * The only files that have more than one zone are conventional zone * files with aggregated conventional zones, for which the inode zone * size is always larger than the device zone size. */ if (zi->i_zone_size > bdev_zone_sectors(sb->s_bdev)) nr_zones = zi->i_zone_size >> (sbi->s_zone_sectors_shift + SECTOR_SHIFT); /* * 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, zi->i_zsector, nr_zones, zonefs_io_error_cb, &err); if (ret != nr_zones) zonefs_err(sb, "Get inode %lu zone information failed %d\n", inode->i_ino, ret); memalloc_noio_restore(noio_flag); } static void zonefs_io_error(struct inode *inode, bool write) { struct zonefs_inode_info *zi = ZONEFS_I(inode); mutex_lock(&zi->i_truncate_mutex); __zonefs_io_error(inode, write); mutex_unlock(&zi->i_truncate_mutex); } static int zonefs_file_truncate(struct inode *inode, loff_t isize) { struct zonefs_inode_info *zi = ZONEFS_I(inode); loff_t old_isize; enum req_opf op; int ret = 0; /* * Only sequential zone files can be truncated and truncation is allowed * only down to a 0 size, which is equivalent to a zone reset, and to * the maximum file size, which is equivalent to a zone finish. */ if (zi->i_ztype != ZONEFS_ZTYPE_SEQ) return -EPERM; if (!isize) op = REQ_OP_ZONE_RESET; else if (isize == zi->i_max_size) op = REQ_OP_ZONE_FINISH; else return -EPERM; inode_dio_wait(inode); /* Serialize against page faults */ filemap_invalidate_lock(inode->i_mapping); /* Serialize against zonefs_iomap_begin() */ mutex_lock(&zi->i_truncate_mutex); old_isize = i_size_read(inode); if (isize == old_isize) goto unlock; ret = zonefs_zone_mgmt(inode, op); if (ret) goto unlock; /* * If the mount option ZONEFS_MNTOPT_EXPLICIT_OPEN is set, * take care of open zones. */ if (zi->i_flags & ZONEFS_ZONE_OPEN) { /* * Truncating a zone to EMPTY or FULL is the equivalent of * closing the zone. For a truncation to 0, we need to * re-open the zone to ensure new writes can be processed. * For a truncation to the maximum file size, the zone is * closed and writes cannot be accepted anymore, so clear * the open flag. */ if (!isize) ret = zonefs_zone_mgmt(inode, REQ_OP_ZONE_OPEN); else zi->i_flags &= ~ZONEFS_ZONE_OPEN; } zonefs_update_stats(inode, isize); truncate_setsize(inode, isize); zi->i_wpoffset = isize; unlock: mutex_unlock(&zi->i_truncate_mutex); filemap_invalidate_unlock(inode->i_mapping); return ret; } static int zonefs_inode_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, struct iattr *iattr) { struct inode *inode = d_inode(dentry); int ret; if (unlikely(IS_IMMUTABLE(inode))) return -EPERM; ret = setattr_prepare(&init_user_ns, 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(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(&init_user_ns, inode, iattr); return 0; } static const struct inode_operations zonefs_file_inode_operations = { .setattr = zonefs_inode_setattr, }; static int zonefs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync) { struct inode *inode = file_inode(file); int ret = 0; if (unlikely(IS_IMMUTABLE(inode))) return -EPERM; /* * Since only direct writes are allowed in sequential files, page cache * flush is needed only for conventional zone files. */ if (ZONEFS_I(inode)->i_ztype == ZONEFS_ZTYPE_CNV) ret = file_write_and_wait_range(file, start, end); if (!ret) ret = blkdev_issue_flush(inode->i_sb->s_bdev); if (ret) zonefs_io_error(inode, true); return ret; } static vm_fault_t zonefs_filemap_page_mkwrite(struct vm_fault *vmf) { struct inode *inode = file_inode(vmf->vma->vm_file); struct zonefs_inode_info *zi = ZONEFS_I(inode); vm_fault_t ret; if (unlikely(IS_IMMUTABLE(inode))) return VM_FAULT_SIGBUS; /* * Sanity check: only conventional zone files can have shared * writeable mappings. */ if (WARN_ON_ONCE(zi->i_ztype != ZONEFS_ZTYPE_CNV)) return VM_FAULT_NOPAGE; sb_start_pagefault(inode->i_sb); file_update_time(vmf->vma->vm_file); /* Serialize against truncates */ filemap_invalidate_lock_shared(inode->i_mapping); ret = iomap_page_mkwrite(vmf, &zonefs_write_iomap_ops); filemap_invalidate_unlock_shared(inode->i_mapping); sb_end_pagefault(inode->i_sb); return ret; } static const struct vm_operations_struct zonefs_file_vm_ops = { .fault = filemap_fault, .map_pages = filemap_map_pages, .page_mkwrite = zonefs_filemap_page_mkwrite, }; static int zonefs_file_mmap(struct file *file, struct vm_area_struct *vma) { /* * Conventional zones accept random writes, so their files can support * shared writable mappings. For sequential zone files, only read * mappings are possible since there are no guarantees for write * ordering between msync() and page cache writeback. */ if (ZONEFS_I(file_inode(file))->i_ztype == ZONEFS_ZTYPE_SEQ && (vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE)) return -EINVAL; file_accessed(file); vma->vm_ops = &zonefs_file_vm_ops; return 0; } static loff_t zonefs_file_llseek(struct file *file, loff_t offset, int whence) { loff_t isize = i_size_read(file_inode(file)); /* * Seeks are limited to below the zone size for conventional zones * and below the zone write pointer for sequential zones. In both * cases, this limit is the inode size. */ return generic_file_llseek_size(file, offset, whence, isize, isize); } static int zonefs_file_write_dio_end_io(struct kiocb *iocb, ssize_t size, int error, unsigned int flags) { struct inode *inode = file_inode(iocb->ki_filp); struct zonefs_inode_info *zi = ZONEFS_I(inode); if (error) { zonefs_io_error(inode, true); return error; } if (size && zi->i_ztype != ZONEFS_ZTYPE_CNV) { /* * Note that we may be seeing completions out of order, * but that is not a problem since a write completed * successfully necessarily means that all preceding writes * were also successful. So we can safely increase the inode * size to the write end location. */ mutex_lock(&zi->i_truncate_mutex); if (i_size_read(inode) < iocb->ki_pos + size) { zonefs_update_stats(inode, iocb->ki_pos + size); zonefs_i_size_write(inode, iocb->ki_pos + size); } mutex_unlock(&zi->i_truncate_mutex); } return 0; } static const struct iomap_dio_ops zonefs_write_dio_ops = { .end_io = zonefs_file_write_dio_end_io, }; static ssize_t zonefs_file_dio_append(struct kiocb *iocb, struct iov_iter *from) { struct inode *inode = file_inode(iocb->ki_filp); struct zonefs_inode_info *zi = ZONEFS_I(inode); struct block_device *bdev = inode->i_sb->s_bdev; unsigned int max = bdev_max_zone_append_sectors(bdev); pgoff_t start, end; struct bio *bio; ssize_t size; int nr_pages; ssize_t ret; max = ALIGN_DOWN(max << SECTOR_SHIFT, inode->i_sb->s_blocksize); iov_iter_truncate(from, max); /* * If the inode block size (zone write granularity) is smaller than the * page size, we may be appending data belonging to the last page of the * inode straddling inode->i_size, with that page already cached due to * a buffered read or readahead. So make sure to invalidate that page. * This will always be a no-op for the case where the block size is * equal to the page size. */ start = iocb->ki_pos >> PAGE_SHIFT; end = (iocb->ki_pos + iov_iter_count(from) - 1) >> PAGE_SHIFT; if (invalidate_inode_pages2_range(inode->i_mapping, start, end)) return -EBUSY; nr_pages = iov_iter_npages(from, BIO_MAX_VECS); if (!nr_pages) return 0; bio = bio_alloc(GFP_NOFS, nr_pages); bio_set_dev(bio, bdev); bio->bi_iter.bi_sector = zi->i_zsector; bio->bi_write_hint = iocb->ki_hint; bio->bi_ioprio = iocb->ki_ioprio; bio->bi_opf = REQ_OP_ZONE_APPEND | REQ_SYNC | REQ_IDLE; if (iocb->ki_flags & IOCB_DSYNC) bio->bi_opf |= REQ_FUA; ret = bio_iov_iter_get_pages(bio, from); if (unlikely(ret)) goto out_release; size = bio->bi_iter.bi_size; task_io_account_write(size); if (iocb->ki_flags & IOCB_HIPRI) bio_set_polled(bio, iocb); ret = submit_bio_wait(bio); /* * If the file zone was written underneath the file system, the zone * write pointer may not be where we expect it to be, but the zone * append write can still succeed. So check manually that we wrote where * we intended to, that is, at zi->i_wpoffset. */ if (!ret) { sector_t wpsector = zi->i_zsector + (zi->i_wpoffset >> SECTOR_SHIFT); if (bio->bi_iter.bi_sector != wpsector) { zonefs_warn(inode->i_sb, "Corrupted write pointer %llu for zone at %llu\n", bio->bi_iter.bi_sector, zi->i_zsector); ret = -EIO; } } zonefs_file_write_dio_end_io(iocb, size, ret, 0); trace_zonefs_file_dio_append(inode, size, ret); out_release: bio_release_pages(bio, false); bio_put(bio); if (ret >= 0) { iocb->ki_pos += size; return size; } return ret; } /* * Do not exceed the LFS limits nor the file zone size. If pos is under the * limit it becomes a short access. If it exceeds the limit, return -EFBIG. */ static loff_t zonefs_write_check_limits(struct file *file, loff_t pos, loff_t count) { struct inode *inode = file_inode(file); struct zonefs_inode_info *zi = ZONEFS_I(inode); loff_t limit = rlimit(RLIMIT_FSIZE); loff_t max_size = zi->i_max_size; if (limit != RLIM_INFINITY) { if (pos >= limit) { send_sig(SIGXFSZ, current, 0); return -EFBIG; } count = min(count, limit - pos); } if (!(file->f_flags & O_LARGEFILE)) max_size = min_t(loff_t, MAX_NON_LFS, max_size); if (unlikely(pos >= max_size)) return -EFBIG; return min(count, max_size - pos); } static ssize_t zonefs_write_checks(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; struct inode *inode = file_inode(file); struct zonefs_inode_info *zi = ZONEFS_I(inode); loff_t count; if (IS_SWAPFILE(inode)) return -ETXTBSY; if (!iov_iter_count(from)) return 0; if ((iocb->ki_flags & IOCB_NOWAIT) && !(iocb->ki_flags & IOCB_DIRECT)) return -EINVAL; if (iocb->ki_flags & IOCB_APPEND) { if (zi->i_ztype != ZONEFS_ZTYPE_SEQ) return -EINVAL; mutex_lock(&zi->i_truncate_mutex); iocb->ki_pos = zi->i_wpoffset; mutex_unlock(&zi->i_truncate_mutex); } count = zonefs_write_check_limits(file, iocb->ki_pos, iov_iter_count(from)); if (count < 0) return count; iov_iter_truncate(from, count); return iov_iter_count(from); } /* * Handle direct writes. For sequential zone files, this is the only possible * write path. For these files, check that the user is issuing writes * sequentially from the end of the file. This code assumes that the block layer * delivers write requests to the device in sequential order. This is always the * case if a block IO scheduler implementing the ELEVATOR_F_ZBD_SEQ_WRITE * elevator feature is being used (e.g. mq-deadline). The block layer always * automatically select such an elevator for zoned block devices during the * device initialization. */ static ssize_t zonefs_file_dio_write(struct kiocb *iocb, struct iov_iter *from) { struct inode *inode = file_inode(iocb->ki_filp); struct zonefs_inode_info *zi = ZONEFS_I(inode); struct super_block *sb = inode->i_sb; bool sync = is_sync_kiocb(iocb); bool append = false; ssize_t ret, count; /* * For async direct IOs to sequential zone files, refuse IOCB_NOWAIT * as this can cause write reordering (e.g. the first aio gets EAGAIN * on the inode lock but the second goes through but is now unaligned). */ if (zi->i_ztype == ZONEFS_ZTYPE_SEQ && !sync && (iocb->ki_flags & IOCB_NOWAIT)) return -EOPNOTSUPP; if (iocb->ki_flags & IOCB_NOWAIT) { if (!inode_trylock(inode)) return -EAGAIN; } else { inode_lock(inode); } count = zonefs_write_checks(iocb, from); if (count <= 0) { ret = count; goto inode_unlock; } if ((iocb->ki_pos | count) & (sb->s_blocksize - 1)) { ret = -EINVAL; goto inode_unlock; } /* Enforce sequential writes (append only) in sequential zones */ if (zi->i_ztype == ZONEFS_ZTYPE_SEQ) { mutex_lock(&zi->i_truncate_mutex); if (iocb->ki_pos != zi->i_wpoffset) { mutex_unlock(&zi->i_truncate_mutex); ret = -EINVAL; goto inode_unlock; } mutex_unlock(&zi->i_truncate_mutex); append = sync; } if (append) ret = zonefs_file_dio_append(iocb, from); else ret = iomap_dio_rw(iocb, from, &zonefs_write_iomap_ops, &zonefs_write_dio_ops, 0, 0); if (zi->i_ztype == ZONEFS_ZTYPE_SEQ && (ret > 0 || ret == -EIOCBQUEUED)) { if (ret > 0) count = ret; mutex_lock(&zi->i_truncate_mutex); zi->i_wpoffset += count; mutex_unlock(&zi->i_truncate_mutex); } inode_unlock: inode_unlock(inode); return ret; } static ssize_t zonefs_file_buffered_write(struct kiocb *iocb, struct iov_iter *from) { struct inode *inode = file_inode(iocb->ki_filp); struct zonefs_inode_info *zi = ZONEFS_I(inode); ssize_t ret; /* * Direct IO writes are mandatory for sequential zone files so that the * write IO issuing order is preserved. */ if (zi->i_ztype != ZONEFS_ZTYPE_CNV) return -EIO; if (iocb->ki_flags & IOCB_NOWAIT) { if (!inode_trylock(inode)) return -EAGAIN; } else { inode_lock(inode); } ret = zonefs_write_checks(iocb, from); if (ret <= 0) goto inode_unlock; ret = iomap_file_buffered_write(iocb, from, &zonefs_write_iomap_ops); if (ret > 0) iocb->ki_pos += ret; else if (ret == -EIO) zonefs_io_error(inode, true); inode_unlock: inode_unlock(inode); if (ret > 0) ret = generic_write_sync(iocb, ret); return ret; } static ssize_t zonefs_file_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct inode *inode = file_inode(iocb->ki_filp); if (unlikely(IS_IMMUTABLE(inode))) return -EPERM; if (sb_rdonly(inode->i_sb)) return -EROFS; /* Write operations beyond the zone size are not allowed */ if (iocb->ki_pos >= ZONEFS_I(inode)->i_max_size) return -EFBIG; if (iocb->ki_flags & IOCB_DIRECT) { ssize_t ret = zonefs_file_dio_write(iocb, from); if (ret != -ENOTBLK) return ret; } return zonefs_file_buffered_write(iocb, from); } static int zonefs_file_read_dio_end_io(struct kiocb *iocb, ssize_t size, int error, unsigned int flags) { if (error) { zonefs_io_error(file_inode(iocb->ki_filp), false); return error; } return 0; } static const struct iomap_dio_ops zonefs_read_dio_ops = { .end_io = zonefs_file_read_dio_end_io, }; static ssize_t zonefs_file_read_iter(struct kiocb *iocb, struct iov_iter *to) { struct inode *inode = file_inode(iocb->ki_filp); struct zonefs_inode_info *zi = ZONEFS_I(inode); struct super_block *sb = inode->i_sb; loff_t isize; ssize_t ret; /* Offline zones cannot be read */ if (unlikely(IS_IMMUTABLE(inode) && !(inode->i_mode & 0777))) return -EPERM; if (iocb->ki_pos >= zi->i_max_size) return 0; if (iocb->ki_flags & IOCB_NOWAIT) { if (!inode_trylock_shared(inode)) return -EAGAIN; } else { inode_lock_shared(inode); } /* Limit read operations to written data */ mutex_lock(&zi->i_truncate_mutex); isize = i_size_read(inode); if (iocb->ki_pos >= isize) { mutex_unlock(&zi->i_truncate_mutex); ret = 0; goto inode_unlock; } iov_iter_truncate(to, isize - iocb->ki_pos); mutex_unlock(&zi->i_truncate_mutex); if (iocb->ki_flags & IOCB_DIRECT) { size_t count = iov_iter_count(to); if ((iocb->ki_pos | count) & (sb->s_blocksize - 1)) { ret = -EINVAL; goto inode_unlock; } file_accessed(iocb->ki_filp); ret = iomap_dio_rw(iocb, to, &zonefs_read_iomap_ops, &zonefs_read_dio_ops, 0, 0); } else { ret = generic_file_read_iter(iocb, to); if (ret == -EIO) zonefs_io_error(inode, false); } inode_unlock: inode_unlock_shared(inode); return ret; } static inline bool zonefs_file_use_exp_open(struct inode *inode, struct file *file) { struct zonefs_inode_info *zi = ZONEFS_I(inode); struct zonefs_sb_info *sbi = ZONEFS_SB(inode->i_sb); if (!(sbi->s_mount_opts & ZONEFS_MNTOPT_EXPLICIT_OPEN)) return false; if (zi->i_ztype != ZONEFS_ZTYPE_SEQ) return false; if (!(file->f_mode & FMODE_WRITE)) return false; return true; } static int zonefs_open_zone(struct inode *inode) { struct zonefs_inode_info *zi = ZONEFS_I(inode); struct zonefs_sb_info *sbi = ZONEFS_SB(inode->i_sb); int ret = 0; mutex_lock(&zi->i_truncate_mutex); if (!zi->i_wr_refcnt) { if (atomic_inc_return(&sbi->s_open_zones) > sbi->s_max_open_zones) { atomic_dec(&sbi->s_open_zones); ret = -EBUSY; goto unlock; } if (i_size_read(inode) < zi->i_max_size) { ret = zonefs_zone_mgmt(inode, REQ_OP_ZONE_OPEN); if (ret) { atomic_dec(&sbi->s_open_zones); goto unlock; } zi->i_flags |= ZONEFS_ZONE_OPEN; } } zi->i_wr_refcnt++; unlock: mutex_unlock(&zi->i_truncate_mutex); return ret; } static int zonefs_file_open(struct inode *inode, struct file *file) { int ret; ret = generic_file_open(inode, file); if (ret) return ret; if (zonefs_file_use_exp_open(inode, file)) return zonefs_open_zone(inode); return 0; } static void zonefs_close_zone(struct inode *inode) { struct zonefs_inode_info *zi = ZONEFS_I(inode); int ret = 0; mutex_lock(&zi->i_truncate_mutex); zi->i_wr_refcnt--; if (!zi->i_wr_refcnt) { struct zonefs_sb_info *sbi = ZONEFS_SB(inode->i_sb); struct super_block *sb = inode->i_sb; /* * If the file zone is full, it is not open anymore and we only * need to decrement the open count. */ if (!(zi->i_flags & ZONEFS_ZONE_OPEN)) goto dec; ret = zonefs_zone_mgmt(inode, REQ_OP_ZONE_CLOSE); if (ret) { __zonefs_io_error(inode, false); /* * Leaving zones explicitly open may lead to a state * where most zones cannot be written (zone resources * exhausted). So take preventive action by remounting * read-only. */ if (zi->i_flags & ZONEFS_ZONE_OPEN && !(sb->s_flags & SB_RDONLY)) { zonefs_warn(sb, "closing zone failed, remounting filesystem read-only\n"); sb->s_flags |= SB_RDONLY; } } zi->i_flags &= ~ZONEFS_ZONE_OPEN; dec: atomic_dec(&sbi->s_open_zones); } mutex_unlock(&zi->i_truncate_mutex); } static int zonefs_file_release(struct inode *inode, struct file *file) { /* * If we explicitly open a zone we must close it again as well, but the * zone management operation can fail (either due to an IO error or as * the zone has gone offline or read-only). Make sure we don't fail the * close(2) for user-space. */ if (zonefs_file_use_exp_open(inode, file)) zonefs_close_zone(inode); return 0; } static const struct file_operations zonefs_file_operations = { .open = zonefs_file_open, .release = zonefs_file_release, .fsync = zonefs_file_fsync, .mmap = zonefs_file_mmap, .llseek = zonefs_file_llseek, .read_iter = zonefs_file_read_iter, .write_iter = zonefs_file_write_iter, .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, .iopoll = iomap_dio_iopoll, }; static struct kmem_cache *zonefs_inode_cachep; static struct inode *zonefs_alloc_inode(struct super_block *sb) { struct zonefs_inode_info *zi; zi = kmem_cache_alloc(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; zi->i_flags = 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_nr_files[t]) buf->f_files += sbi->s_nr_files[t] + 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 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 const struct inode_operations zonefs_dir_inode_operations = { .lookup = simple_lookup, .setattr = zonefs_inode_setattr, }; static void zonefs_init_dir_inode(struct inode *parent, struct inode *inode, enum zonefs_ztype type) { struct super_block *sb = parent->i_sb; inode->i_ino = blkdev_nr_zones(sb->s_bdev->bd_disk) + type + 1; inode_init_owner(&init_user_ns, inode, parent, S_IFDIR | 0555); inode->i_op = &zonefs_dir_inode_operations; inode->i_fop = &simple_dir_operations; set_nlink(inode, 2); inc_nlink(parent); } static int zonefs_init_file_inode(struct inode *inode, struct blk_zone *zone, enum zonefs_ztype type) { struct super_block *sb = inode->i_sb; struct zonefs_sb_info *sbi = ZONEFS_SB(sb); struct zonefs_inode_info *zi = ZONEFS_I(inode); int ret = 0; inode->i_ino = zone->start >> sbi->s_zone_sectors_shift; inode->i_mode = S_IFREG | sbi->s_perm; zi->i_ztype = type; zi->i_zsector = zone->start; zi->i_zone_size = zone->len << SECTOR_SHIFT; if (zi->i_zone_size > bdev_zone_sectors(sb->s_bdev) << SECTOR_SHIFT && !(sbi->s_features & ZONEFS_F_AGGRCNV)) { zonefs_err(sb, "zone size %llu doesn't match device's zone sectors %llu\n", zi->i_zone_size, bdev_zone_sectors(sb->s_bdev) << SECTOR_SHIFT); return -EINVAL; } zi->i_max_size = min_t(loff_t, MAX_LFS_FILESIZE, zone->capacity << SECTOR_SHIFT); zi->i_wpoffset = zonefs_check_zone_condition(inode, zone, true, true); inode->i_uid = sbi->s_uid; inode->i_gid = sbi->s_gid; inode->i_size = zi->i_wpoffset; inode->i_blocks = zi->i_max_size >> SECTOR_SHIFT; inode->i_op = &zonefs_file_inode_operations; inode->i_fop = &zonefs_file_operations; inode->i_mapping->a_ops = &zonefs_file_aops; sb->s_maxbytes = max(zi->i_max_size, sb->s_maxbytes); sbi->s_blocks += zi->i_max_size >> sb->s_blocksize_bits; sbi->s_used_blocks += zi->i_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 (type == ZONEFS_ZTYPE_SEQ && (zone->cond == BLK_ZONE_COND_IMP_OPEN || zone->cond == BLK_ZONE_COND_EXP_OPEN)) { mutex_lock(&zi->i_truncate_mutex); ret = zonefs_zone_mgmt(inode, REQ_OP_ZONE_CLOSE); mutex_unlock(&zi->i_truncate_mutex); } return ret; } static struct dentry *zonefs_create_inode(struct dentry *parent, const char *name, struct blk_zone *zone, enum zonefs_ztype type) { struct inode *dir = d_inode(parent); struct dentry *dentry; struct inode *inode; int ret = -ENOMEM; dentry = d_alloc_name(parent, name); if (!dentry) return ERR_PTR(ret); inode = new_inode(parent->d_sb); if (!inode) goto dput; inode->i_ctime = inode->i_mtime = inode->i_atime = dir->i_ctime; if (zone) { ret = zonefs_init_file_inode(inode, zone, type); if (ret) { iput(inode); goto dput; } } else { zonefs_init_dir_inode(dir, inode, type); } d_add(dentry, inode); dir->i_size++; return dentry; dput: dput(dentry); return ERR_PTR(ret); } struct zonefs_zone_data { struct super_block *sb; unsigned int nr_zones[ZONEFS_ZTYPE_MAX]; struct blk_zone *zones; }; /* * Create a zone group and populate it with zone files. */ static int zonefs_create_zgroup(struct zonefs_zone_data *zd, enum zonefs_ztype type) { struct super_block *sb = zd->sb; struct zonefs_sb_info *sbi = ZONEFS_SB(sb); struct blk_zone *zone, *next, *end; const char *zgroup_name; char *file_name; struct dentry *dir, *dent; unsigned int n = 0; int ret; /* If the group is empty, there is nothing to do */ if (!zd->nr_zones[type]) return 0; file_name = kmalloc(ZONEFS_NAME_MAX, GFP_KERNEL); if (!file_name) return -ENOMEM; if (type == ZONEFS_ZTYPE_CNV) zgroup_name = "cnv"; else zgroup_name = "seq"; dir = zonefs_create_inode(sb->s_root, zgroup_name, NULL, type); if (IS_ERR(dir)) { ret = PTR_ERR(dir); goto free; } /* * The first zone contains the super block: skip it. */ end = zd->zones + blkdev_nr_zones(sb->s_bdev->bd_disk); for (zone = &zd->zones[1]; zone < end; zone = next) { next = zone + 1; if (zonefs_zone_type(zone) != type) continue; /* * 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 (type == ZONEFS_ZTYPE_CNV && (sbi->s_features & ZONEFS_F_AGGRCNV)) { for (; next < end; next++) { if (zonefs_zone_type(next) != type) 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; } if (zone->capacity != zone->len) { zonefs_err(sb, "Invalid conventional zone capacity\n"); ret = -EINVAL; goto free; } } /* * Use the file number within its group as file name. */ snprintf(file_name, ZONEFS_NAME_MAX - 1, "%u", n); dent = zonefs_create_inode(dir, file_name, zone, type); if (IS_ERR(dent)) { ret = PTR_ERR(dent); goto free; } n++; } zonefs_info(sb, "Zone group \"%s\" has %u file%s\n", zgroup_name, n, n > 1 ? "s" : ""); sbi->s_nr_files[type] = n; ret = 0; free: kfree(file_name); return ret; } static int zonefs_get_zone_info_cb(struct blk_zone *zone, unsigned int idx, void *data) { struct zonefs_zone_data *zd = data; /* * Count the number of usable zones: the first zone at index 0 contains * the super block and is ignored. */ switch (zone->type) { case BLK_ZONE_TYPE_CONVENTIONAL: zone->wp = zone->start + zone->len; if (idx) zd->nr_zones[ZONEFS_ZTYPE_CNV]++; break; case BLK_ZONE_TYPE_SEQWRITE_REQ: case BLK_ZONE_TYPE_SEQWRITE_PREF: if (idx) zd->nr_zones[ZONEFS_ZTYPE_SEQ]++; 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(blkdev_nr_zones(bdev->bd_disk), 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 != blkdev_nr_zones(bdev->bd_disk)) { zonefs_err(zd->sb, "Invalid zone report (%d/%u zones)\n", ret, blkdev_nr_zones(bdev->bd_disk)); return -EIO; } return 0; } static inline void zonefs_cleanup_zone_info(struct zonefs_zone_data *zd) { kvfree(zd->zones); } /* * 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, &bio_vec, 1); bio.bi_iter.bi_sector = 0; bio.bi_opf = REQ_OP_READ; bio_set_dev(&bio, sb->s_bdev); bio_add_page(&bio, page, PAGE_SIZE, 0); ret = submit_bio_wait(&bio); if (ret) goto free_page; super = kmap(page); ret = -EINVAL; if (le32_to_cpu(super->s_magic) != ZONEFS_MAGIC) goto unmap; 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 unmap; } 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 unmap; } 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 unmap; } } 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 unmap; } } 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 unmap; } import_uuid(&sbi->s_uuid, super->s_uuid); ret = 0; unmap: kunmap(page); free_page: __free_page(page); return ret; } /* * 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_zone_data zd; struct zonefs_sb_info *sbi; struct inode *inode; enum zonefs_ztype t; 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; sbi->s_max_open_zones = bdev_max_open_zones(sb->s_bdev); atomic_set(&sbi->s_open_zones, 0); ret = zonefs_read_super(sb); if (ret) return ret; ret = zonefs_parse_options(sb, data); if (ret) return ret; memset(&zd, 0, sizeof(struct zonefs_zone_data)); zd.sb = sb; ret = zonefs_get_zone_info(&zd); if (ret) goto cleanup; zonefs_info(sb, "Mounting %u zones", blkdev_nr_zones(sb->s_bdev->bd_disk)); if (!sbi->s_max_open_zones && sbi->s_mount_opts & ZONEFS_MNTOPT_EXPLICIT_OPEN) { zonefs_info(sb, "No open zones limit. Ignoring explicit_open mount option\n"); sbi->s_mount_opts &= ~ZONEFS_MNTOPT_EXPLICIT_OPEN; } /* Create root directory inode */ ret = -ENOMEM; inode = new_inode(sb); if (!inode) goto cleanup; inode->i_ino = blkdev_nr_zones(sb->s_bdev->bd_disk); inode->i_mode = S_IFDIR | 0555; inode->i_ctime = inode->i_mtime = inode->i_atime = current_time(inode); inode->i_op = &zonefs_dir_inode_operations; inode->i_fop = &simple_dir_operations; set_nlink(inode, 2); sb->s_root = d_make_root(inode); if (!sb->s_root) goto cleanup; /* Create and populate files in zone groups directories */ for (t = 0; t < ZONEFS_ZTYPE_MAX; t++) { ret = zonefs_create_zgroup(&zd, t); if (ret) break; } cleanup: zonefs_cleanup_zone_info(&zd); 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); if (sb->s_root) d_genocide(sb->s_root); kill_block_super(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 = register_filesystem(&zonefs_type); if (ret) { zonefs_destroy_inodecache(); return ret; } return 0; } static void __exit zonefs_exit(void) { zonefs_destroy_inodecache(); unregister_filesystem(&zonefs_type); } 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);