// SPDX-License-Identifier: GPL-2.0 /* * Zoned block device handling * * Copyright (c) 2015, Hannes Reinecke * Copyright (c) 2015, SUSE Linux GmbH * * Copyright (c) 2016, Damien Le Moal * Copyright (c) 2016, Western Digital * Copyright (c) 2024, Western Digital Corporation or its affiliates. */ #include #include #include #include #include #include #include #include #include #include #include "blk.h" #include "blk-mq-sched.h" #include "blk-mq-debugfs.h" #define ZONE_COND_NAME(name) [BLK_ZONE_COND_##name] = #name static const char *const zone_cond_name[] = { ZONE_COND_NAME(NOT_WP), ZONE_COND_NAME(EMPTY), ZONE_COND_NAME(IMP_OPEN), ZONE_COND_NAME(EXP_OPEN), ZONE_COND_NAME(CLOSED), ZONE_COND_NAME(READONLY), ZONE_COND_NAME(FULL), ZONE_COND_NAME(OFFLINE), }; #undef ZONE_COND_NAME /* * Per-zone write plug. * @node: hlist_node structure for managing the plug using a hash table. * @link: To list the plug in the zone write plug error list of the disk. * @ref: Zone write plug reference counter. A zone write plug reference is * always at least 1 when the plug is hashed in the disk plug hash table. * The reference is incremented whenever a new BIO needing plugging is * submitted and when a function needs to manipulate a plug. The * reference count is decremented whenever a plugged BIO completes and * when a function that referenced the plug returns. The initial * reference is dropped whenever the zone of the zone write plug is reset, * finished and when the zone becomes full (last write BIO to the zone * completes). * @lock: Spinlock to atomically manipulate the plug. * @flags: Flags indicating the plug state. * @zone_no: The number of the zone the plug is managing. * @wp_offset: The zone write pointer location relative to the start of the zone * as a number of 512B sectors. * @bio_list: The list of BIOs that are currently plugged. * @bio_work: Work struct to handle issuing of plugged BIOs * @rcu_head: RCU head to free zone write plugs with an RCU grace period. * @disk: The gendisk the plug belongs to. */ struct blk_zone_wplug { struct hlist_node node; struct list_head link; atomic_t ref; spinlock_t lock; unsigned int flags; unsigned int zone_no; unsigned int wp_offset; struct bio_list bio_list; struct work_struct bio_work; struct rcu_head rcu_head; struct gendisk *disk; }; /* * Zone write plug flags bits: * - BLK_ZONE_WPLUG_PLUGGED: Indicates that the zone write plug is plugged, * that is, that write BIOs are being throttled due to a write BIO already * being executed or the zone write plug bio list is not empty. * - BLK_ZONE_WPLUG_ERROR: Indicates that a write error happened which will be * recovered with a report zone to update the zone write pointer offset. * - BLK_ZONE_WPLUG_UNHASHED: Indicates that the zone write plug was removed * from the disk hash table and that the initial reference to the zone * write plug set when the plug was first added to the hash table has been * dropped. This flag is set when a zone is reset, finished or become full, * to prevent new references to the zone write plug to be taken for * newly incoming BIOs. A zone write plug flagged with this flag will be * freed once all remaining references from BIOs or functions are dropped. */ #define BLK_ZONE_WPLUG_PLUGGED (1U << 0) #define BLK_ZONE_WPLUG_ERROR (1U << 1) #define BLK_ZONE_WPLUG_UNHASHED (1U << 2) #define BLK_ZONE_WPLUG_BUSY (BLK_ZONE_WPLUG_PLUGGED | BLK_ZONE_WPLUG_ERROR) /** * blk_zone_cond_str - Return string XXX in BLK_ZONE_COND_XXX. * @zone_cond: BLK_ZONE_COND_XXX. * * Description: Centralize block layer function to convert BLK_ZONE_COND_XXX * into string format. Useful in the debugging and tracing zone conditions. For * invalid BLK_ZONE_COND_XXX it returns string "UNKNOWN". */ const char *blk_zone_cond_str(enum blk_zone_cond zone_cond) { static const char *zone_cond_str = "UNKNOWN"; if (zone_cond < ARRAY_SIZE(zone_cond_name) && zone_cond_name[zone_cond]) zone_cond_str = zone_cond_name[zone_cond]; return zone_cond_str; } EXPORT_SYMBOL_GPL(blk_zone_cond_str); /** * bdev_nr_zones - Get number of zones * @bdev: Target device * * Return the total number of zones of a zoned block device. For a block * device without zone capabilities, the number of zones is always 0. */ unsigned int bdev_nr_zones(struct block_device *bdev) { sector_t zone_sectors = bdev_zone_sectors(bdev); if (!bdev_is_zoned(bdev)) return 0; return (bdev_nr_sectors(bdev) + zone_sectors - 1) >> ilog2(zone_sectors); } EXPORT_SYMBOL_GPL(bdev_nr_zones); /** * blkdev_report_zones - Get zones information * @bdev: Target block device * @sector: Sector from which to report zones * @nr_zones: Maximum number of zones to report * @cb: Callback function called for each reported zone * @data: Private data for the callback * * Description: * Get zone information starting from the zone containing @sector for at most * @nr_zones, and call @cb for each zone reported by the device. * To report all zones in a device starting from @sector, the BLK_ALL_ZONES * constant can be passed to @nr_zones. * Returns the number of zones reported by the device, or a negative errno * value in case of failure. * * Note: The caller must use memalloc_noXX_save/restore() calls to control * memory allocations done within this function. */ int blkdev_report_zones(struct block_device *bdev, sector_t sector, unsigned int nr_zones, report_zones_cb cb, void *data) { struct gendisk *disk = bdev->bd_disk; sector_t capacity = get_capacity(disk); if (!bdev_is_zoned(bdev) || WARN_ON_ONCE(!disk->fops->report_zones)) return -EOPNOTSUPP; if (!nr_zones || sector >= capacity) return 0; return disk->fops->report_zones(disk, sector, nr_zones, cb, data); } EXPORT_SYMBOL_GPL(blkdev_report_zones); static inline unsigned long *blk_alloc_zone_bitmap(int node, unsigned int nr_zones) { return kcalloc_node(BITS_TO_LONGS(nr_zones), sizeof(unsigned long), GFP_NOIO, node); } static int blk_zone_need_reset_cb(struct blk_zone *zone, unsigned int idx, void *data) { /* * For an all-zones reset, ignore conventional, empty, read-only * and offline zones. */ switch (zone->cond) { case BLK_ZONE_COND_NOT_WP: case BLK_ZONE_COND_EMPTY: case BLK_ZONE_COND_READONLY: case BLK_ZONE_COND_OFFLINE: return 0; default: set_bit(idx, (unsigned long *)data); return 0; } } static int blkdev_zone_reset_all_emulated(struct block_device *bdev) { struct gendisk *disk = bdev->bd_disk; sector_t capacity = bdev_nr_sectors(bdev); sector_t zone_sectors = bdev_zone_sectors(bdev); unsigned long *need_reset; struct bio *bio = NULL; sector_t sector = 0; int ret; need_reset = blk_alloc_zone_bitmap(disk->queue->node, disk->nr_zones); if (!need_reset) return -ENOMEM; ret = disk->fops->report_zones(disk, 0, disk->nr_zones, blk_zone_need_reset_cb, need_reset); if (ret < 0) goto out_free_need_reset; ret = 0; while (sector < capacity) { if (!test_bit(disk_zone_no(disk, sector), need_reset)) { sector += zone_sectors; continue; } bio = blk_next_bio(bio, bdev, 0, REQ_OP_ZONE_RESET | REQ_SYNC, GFP_KERNEL); bio->bi_iter.bi_sector = sector; sector += zone_sectors; /* This may take a while, so be nice to others */ cond_resched(); } if (bio) { ret = submit_bio_wait(bio); bio_put(bio); } out_free_need_reset: kfree(need_reset); return ret; } static int blkdev_zone_reset_all(struct block_device *bdev) { struct bio bio; bio_init(&bio, bdev, NULL, 0, REQ_OP_ZONE_RESET_ALL | REQ_SYNC); return submit_bio_wait(&bio); } /** * blkdev_zone_mgmt - Execute a zone management operation on a range of zones * @bdev: Target block device * @op: Operation to be performed on the zones * @sector: Start sector of the first zone to operate on * @nr_sectors: Number of sectors, should be at least the length of one zone and * must be zone size aligned. * * Description: * Perform the specified operation on the range of zones specified by * @sector..@sector+@nr_sectors. Specifying the entire disk sector range * is valid, but the specified range should not contain conventional zones. * The operation to execute on each zone can be a zone reset, open, close * or finish request. */ int blkdev_zone_mgmt(struct block_device *bdev, enum req_op op, sector_t sector, sector_t nr_sectors) { struct request_queue *q = bdev_get_queue(bdev); sector_t zone_sectors = bdev_zone_sectors(bdev); sector_t capacity = bdev_nr_sectors(bdev); sector_t end_sector = sector + nr_sectors; struct bio *bio = NULL; int ret = 0; if (!bdev_is_zoned(bdev)) return -EOPNOTSUPP; if (bdev_read_only(bdev)) return -EPERM; if (!op_is_zone_mgmt(op)) return -EOPNOTSUPP; if (end_sector <= sector || end_sector > capacity) /* Out of range */ return -EINVAL; /* Check alignment (handle eventual smaller last zone) */ if (!bdev_is_zone_start(bdev, sector)) return -EINVAL; if (!bdev_is_zone_start(bdev, nr_sectors) && end_sector != capacity) return -EINVAL; /* * In the case of a zone reset operation over all zones, * REQ_OP_ZONE_RESET_ALL can be used with devices supporting this * command. For other devices, we emulate this command behavior by * identifying the zones needing a reset. */ if (op == REQ_OP_ZONE_RESET && sector == 0 && nr_sectors == capacity) { if (!blk_queue_zone_resetall(q)) return blkdev_zone_reset_all_emulated(bdev); return blkdev_zone_reset_all(bdev); } while (sector < end_sector) { bio = blk_next_bio(bio, bdev, 0, op | REQ_SYNC, GFP_KERNEL); bio->bi_iter.bi_sector = sector; sector += zone_sectors; /* This may take a while, so be nice to others */ cond_resched(); } ret = submit_bio_wait(bio); bio_put(bio); return ret; } EXPORT_SYMBOL_GPL(blkdev_zone_mgmt); struct zone_report_args { struct blk_zone __user *zones; }; static int blkdev_copy_zone_to_user(struct blk_zone *zone, unsigned int idx, void *data) { struct zone_report_args *args = data; if (copy_to_user(&args->zones[idx], zone, sizeof(struct blk_zone))) return -EFAULT; return 0; } /* * BLKREPORTZONE ioctl processing. * Called from blkdev_ioctl. */ int blkdev_report_zones_ioctl(struct block_device *bdev, unsigned int cmd, unsigned long arg) { void __user *argp = (void __user *)arg; struct zone_report_args args; struct blk_zone_report rep; int ret; if (!argp) return -EINVAL; if (!bdev_is_zoned(bdev)) return -ENOTTY; if (copy_from_user(&rep, argp, sizeof(struct blk_zone_report))) return -EFAULT; if (!rep.nr_zones) return -EINVAL; args.zones = argp + sizeof(struct blk_zone_report); ret = blkdev_report_zones(bdev, rep.sector, rep.nr_zones, blkdev_copy_zone_to_user, &args); if (ret < 0) return ret; rep.nr_zones = ret; rep.flags = BLK_ZONE_REP_CAPACITY; if (copy_to_user(argp, &rep, sizeof(struct blk_zone_report))) return -EFAULT; return 0; } static int blkdev_truncate_zone_range(struct block_device *bdev, blk_mode_t mode, const struct blk_zone_range *zrange) { loff_t start, end; if (zrange->sector + zrange->nr_sectors <= zrange->sector || zrange->sector + zrange->nr_sectors > get_capacity(bdev->bd_disk)) /* Out of range */ return -EINVAL; start = zrange->sector << SECTOR_SHIFT; end = ((zrange->sector + zrange->nr_sectors) << SECTOR_SHIFT) - 1; return truncate_bdev_range(bdev, mode, start, end); } /* * BLKRESETZONE, BLKOPENZONE, BLKCLOSEZONE and BLKFINISHZONE ioctl processing. * Called from blkdev_ioctl. */ int blkdev_zone_mgmt_ioctl(struct block_device *bdev, blk_mode_t mode, unsigned int cmd, unsigned long arg) { void __user *argp = (void __user *)arg; struct blk_zone_range zrange; enum req_op op; int ret; if (!argp) return -EINVAL; if (!bdev_is_zoned(bdev)) return -ENOTTY; if (!(mode & BLK_OPEN_WRITE)) return -EBADF; if (copy_from_user(&zrange, argp, sizeof(struct blk_zone_range))) return -EFAULT; switch (cmd) { case BLKRESETZONE: op = REQ_OP_ZONE_RESET; /* Invalidate the page cache, including dirty pages. */ filemap_invalidate_lock(bdev->bd_inode->i_mapping); ret = blkdev_truncate_zone_range(bdev, mode, &zrange); if (ret) goto fail; break; case BLKOPENZONE: op = REQ_OP_ZONE_OPEN; break; case BLKCLOSEZONE: op = REQ_OP_ZONE_CLOSE; break; case BLKFINISHZONE: op = REQ_OP_ZONE_FINISH; break; default: return -ENOTTY; } ret = blkdev_zone_mgmt(bdev, op, zrange.sector, zrange.nr_sectors); fail: if (cmd == BLKRESETZONE) filemap_invalidate_unlock(bdev->bd_inode->i_mapping); return ret; } static inline bool disk_zone_is_conv(struct gendisk *disk, sector_t sector) { if (!disk->conv_zones_bitmap) return false; return test_bit(disk_zone_no(disk, sector), disk->conv_zones_bitmap); } static bool disk_insert_zone_wplug(struct gendisk *disk, struct blk_zone_wplug *zwplug) { struct blk_zone_wplug *zwplg; unsigned long flags; unsigned int idx = hash_32(zwplug->zone_no, disk->zone_wplugs_hash_bits); /* * Add the new zone write plug to the hash table, but carefully as we * are racing with other submission context, so we may already have a * zone write plug for the same zone. */ spin_lock_irqsave(&disk->zone_wplugs_lock, flags); hlist_for_each_entry_rcu(zwplg, &disk->zone_wplugs_hash[idx], node) { if (zwplg->zone_no == zwplug->zone_no) { spin_unlock_irqrestore(&disk->zone_wplugs_lock, flags); return false; } } hlist_add_head_rcu(&zwplug->node, &disk->zone_wplugs_hash[idx]); spin_unlock_irqrestore(&disk->zone_wplugs_lock, flags); return true; } static struct blk_zone_wplug *disk_get_zone_wplug(struct gendisk *disk, sector_t sector) { unsigned int zno = disk_zone_no(disk, sector); unsigned int idx = hash_32(zno, disk->zone_wplugs_hash_bits); struct blk_zone_wplug *zwplug; rcu_read_lock(); hlist_for_each_entry_rcu(zwplug, &disk->zone_wplugs_hash[idx], node) { if (zwplug->zone_no == zno && atomic_inc_not_zero(&zwplug->ref)) { rcu_read_unlock(); return zwplug; } } rcu_read_unlock(); return NULL; } static void disk_free_zone_wplug_rcu(struct rcu_head *rcu_head) { struct blk_zone_wplug *zwplug = container_of(rcu_head, struct blk_zone_wplug, rcu_head); mempool_free(zwplug, zwplug->disk->zone_wplugs_pool); } static inline void disk_put_zone_wplug(struct blk_zone_wplug *zwplug) { if (atomic_dec_and_test(&zwplug->ref)) { WARN_ON_ONCE(!bio_list_empty(&zwplug->bio_list)); WARN_ON_ONCE(!list_empty(&zwplug->link)); WARN_ON_ONCE(!(zwplug->flags & BLK_ZONE_WPLUG_UNHASHED)); call_rcu(&zwplug->rcu_head, disk_free_zone_wplug_rcu); } } static inline bool disk_should_remove_zone_wplug(struct gendisk *disk, struct blk_zone_wplug *zwplug) { /* If the zone write plug was already removed, we are done. */ if (zwplug->flags & BLK_ZONE_WPLUG_UNHASHED) return false; /* If the zone write plug is still busy, it cannot be removed. */ if (zwplug->flags & BLK_ZONE_WPLUG_BUSY) return false; /* * Completions of BIOs with blk_zone_write_plug_bio_endio() may * happen after handling a request completion with * blk_zone_write_plug_finish_request() (e.g. with split BIOs * that are chained). In such case, disk_zone_wplug_unplug_bio() * should not attempt to remove the zone write plug until all BIO * completions are seen. Check by looking at the zone write plug * reference count, which is 2 when the plug is unused (one reference * taken when the plug was allocated and another reference taken by the * caller context). */ if (atomic_read(&zwplug->ref) > 2) return false; /* We can remove zone write plugs for zones that are empty or full. */ return !zwplug->wp_offset || zwplug->wp_offset >= disk->zone_capacity; } static void disk_remove_zone_wplug(struct gendisk *disk, struct blk_zone_wplug *zwplug) { unsigned long flags; /* If the zone write plug was already removed, we have nothing to do. */ if (zwplug->flags & BLK_ZONE_WPLUG_UNHASHED) return; /* * Mark the zone write plug as unhashed and drop the extra reference we * took when the plug was inserted in the hash table. */ zwplug->flags |= BLK_ZONE_WPLUG_UNHASHED; spin_lock_irqsave(&disk->zone_wplugs_lock, flags); hlist_del_init_rcu(&zwplug->node); spin_unlock_irqrestore(&disk->zone_wplugs_lock, flags); disk_put_zone_wplug(zwplug); } static void blk_zone_wplug_bio_work(struct work_struct *work); /* * Get a reference on the write plug for the zone containing @sector. * If the plug does not exist, it is allocated and hashed. * Return a pointer to the zone write plug with the plug spinlock held. */ static struct blk_zone_wplug *disk_get_and_lock_zone_wplug(struct gendisk *disk, sector_t sector, gfp_t gfp_mask, unsigned long *flags) { unsigned int zno = disk_zone_no(disk, sector); struct blk_zone_wplug *zwplug; again: zwplug = disk_get_zone_wplug(disk, sector); if (zwplug) { /* * Check that a BIO completion or a zone reset or finish * operation has not already removed the zone write plug from * the hash table and dropped its reference count. In such case, * we need to get a new plug so start over from the beginning. */ spin_lock_irqsave(&zwplug->lock, *flags); if (zwplug->flags & BLK_ZONE_WPLUG_UNHASHED) { spin_unlock_irqrestore(&zwplug->lock, *flags); disk_put_zone_wplug(zwplug); goto again; } return zwplug; } /* * Allocate and initialize a zone write plug with an extra reference * so that it is not freed when the zone write plug becomes idle without * the zone being full. */ zwplug = mempool_alloc(disk->zone_wplugs_pool, gfp_mask); if (!zwplug) return NULL; INIT_HLIST_NODE(&zwplug->node); INIT_LIST_HEAD(&zwplug->link); atomic_set(&zwplug->ref, 2); spin_lock_init(&zwplug->lock); zwplug->flags = 0; zwplug->zone_no = zno; zwplug->wp_offset = sector & (disk->queue->limits.chunk_sectors - 1); bio_list_init(&zwplug->bio_list); INIT_WORK(&zwplug->bio_work, blk_zone_wplug_bio_work); zwplug->disk = disk; spin_lock_irqsave(&zwplug->lock, *flags); /* * Insert the new zone write plug in the hash table. This can fail only * if another context already inserted a plug. Retry from the beginning * in such case. */ if (!disk_insert_zone_wplug(disk, zwplug)) { spin_unlock_irqrestore(&zwplug->lock, *flags); mempool_free(zwplug, disk->zone_wplugs_pool); goto again; } return zwplug; } static inline void blk_zone_wplug_bio_io_error(struct blk_zone_wplug *zwplug, struct bio *bio) { struct request_queue *q = zwplug->disk->queue; bio_clear_flag(bio, BIO_ZONE_WRITE_PLUGGING); bio_io_error(bio); disk_put_zone_wplug(zwplug); blk_queue_exit(q); } /* * Abort (fail) all plugged BIOs of a zone write plug. */ static void disk_zone_wplug_abort(struct blk_zone_wplug *zwplug) { struct bio *bio; while ((bio = bio_list_pop(&zwplug->bio_list))) blk_zone_wplug_bio_io_error(zwplug, bio); } /* * Abort (fail) all plugged BIOs of a zone write plug that are not aligned * with the assumed write pointer location of the zone when the BIO will * be unplugged. */ static void disk_zone_wplug_abort_unaligned(struct gendisk *disk, struct blk_zone_wplug *zwplug) { unsigned int zone_capacity = disk->zone_capacity; unsigned int wp_offset = zwplug->wp_offset; struct bio_list bl = BIO_EMPTY_LIST; struct bio *bio; while ((bio = bio_list_pop(&zwplug->bio_list))) { if (wp_offset >= zone_capacity || (bio_op(bio) != REQ_OP_ZONE_APPEND && bio_offset_from_zone_start(bio) != wp_offset)) { blk_zone_wplug_bio_io_error(zwplug, bio); continue; } wp_offset += bio_sectors(bio); bio_list_add(&bl, bio); } bio_list_merge(&zwplug->bio_list, &bl); } static inline void disk_zone_wplug_set_error(struct gendisk *disk, struct blk_zone_wplug *zwplug) { unsigned long flags; if (zwplug->flags & BLK_ZONE_WPLUG_ERROR) return; /* * At this point, we already have a reference on the zone write plug. * However, since we are going to add the plug to the disk zone write * plugs work list, increase its reference count. This reference will * be dropped in disk_zone_wplugs_work() once the error state is * handled, or in disk_zone_wplug_clear_error() if the zone is reset or * finished. */ zwplug->flags |= BLK_ZONE_WPLUG_ERROR; atomic_inc(&zwplug->ref); spin_lock_irqsave(&disk->zone_wplugs_lock, flags); list_add_tail(&zwplug->link, &disk->zone_wplugs_err_list); spin_unlock_irqrestore(&disk->zone_wplugs_lock, flags); } static inline void disk_zone_wplug_clear_error(struct gendisk *disk, struct blk_zone_wplug *zwplug) { unsigned long flags; if (!(zwplug->flags & BLK_ZONE_WPLUG_ERROR)) return; /* * We are racing with the error handling work which drops the reference * on the zone write plug after handling the error state. So remove the * plug from the error list and drop its reference count only if the * error handling has not yet started, that is, if the zone write plug * is still listed. */ spin_lock_irqsave(&disk->zone_wplugs_lock, flags); if (!list_empty(&zwplug->link)) { list_del_init(&zwplug->link); zwplug->flags &= ~BLK_ZONE_WPLUG_ERROR; disk_put_zone_wplug(zwplug); } spin_unlock_irqrestore(&disk->zone_wplugs_lock, flags); } /* * Set a zone write plug write pointer offset to either 0 (zone reset case) * or to the zone size (zone finish case). This aborts all plugged BIOs, which * is fine to do as doing a zone reset or zone finish while writes are in-flight * is a mistake from the user which will most likely cause all plugged BIOs to * fail anyway. */ static void disk_zone_wplug_set_wp_offset(struct gendisk *disk, struct blk_zone_wplug *zwplug, unsigned int wp_offset) { unsigned long flags; spin_lock_irqsave(&zwplug->lock, flags); /* * Make sure that a BIO completion or another zone reset or finish * operation has not already removed the plug from the hash table. */ if (zwplug->flags & BLK_ZONE_WPLUG_UNHASHED) { spin_unlock_irqrestore(&zwplug->lock, flags); return; } /* Update the zone write pointer and abort all plugged BIOs. */ zwplug->wp_offset = wp_offset; disk_zone_wplug_abort(zwplug); /* * Updating the write pointer offset puts back the zone * in a good state. So clear the error flag and decrement the * error count if we were in error state. */ disk_zone_wplug_clear_error(disk, zwplug); /* * The zone write plug now has no BIO plugged: remove it from the * hash table so that it cannot be seen. The plug will be freed * when the last reference is dropped. */ if (disk_should_remove_zone_wplug(disk, zwplug)) disk_remove_zone_wplug(disk, zwplug); spin_unlock_irqrestore(&zwplug->lock, flags); } static bool blk_zone_wplug_handle_reset_or_finish(struct bio *bio, unsigned int wp_offset) { struct gendisk *disk = bio->bi_bdev->bd_disk; sector_t sector = bio->bi_iter.bi_sector; struct blk_zone_wplug *zwplug; /* Conventional zones cannot be reset nor finished. */ if (disk_zone_is_conv(disk, sector)) { bio_io_error(bio); return true; } /* * If we have a zone write plug, set its write pointer offset to 0 * (reset case) or to the zone size (finish case). This will abort all * BIOs plugged for the target zone. It is fine as resetting or * finishing zones while writes are still in-flight will result in the * writes failing anyway. */ zwplug = disk_get_zone_wplug(disk, sector); if (zwplug) { disk_zone_wplug_set_wp_offset(disk, zwplug, wp_offset); disk_put_zone_wplug(zwplug); } return false; } static bool blk_zone_wplug_handle_reset_all(struct bio *bio) { struct gendisk *disk = bio->bi_bdev->bd_disk; struct blk_zone_wplug *zwplug; sector_t sector; /* * Set the write pointer offset of all zone write plugs to 0. This will * abort all plugged BIOs. It is fine as resetting zones while writes * are still in-flight will result in the writes failing anyway. */ for (sector = 0; sector < get_capacity(disk); sector += disk->queue->limits.chunk_sectors) { zwplug = disk_get_zone_wplug(disk, sector); if (zwplug) { disk_zone_wplug_set_wp_offset(disk, zwplug, 0); disk_put_zone_wplug(zwplug); } } return false; } static inline void blk_zone_wplug_add_bio(struct blk_zone_wplug *zwplug, struct bio *bio, unsigned int nr_segs) { /* * Grab an extra reference on the BIO request queue usage counter. * This reference will be reused to submit a request for the BIO for * blk-mq devices and dropped when the BIO is failed and after * it is issued in the case of BIO-based devices. */ percpu_ref_get(&bio->bi_bdev->bd_disk->queue->q_usage_counter); /* * The BIO is being plugged and thus will have to wait for the on-going * write and for all other writes already plugged. So polling makes * no sense. */ bio_clear_polled(bio); /* * Reuse the poll cookie field to store the number of segments when * split to the hardware limits. */ bio->__bi_nr_segments = nr_segs; /* * We always receive BIOs after they are split and ready to be issued. * The block layer passes the parts of a split BIO in order, and the * user must also issue write sequentially. So simply add the new BIO * at the tail of the list to preserve the sequential write order. */ bio_list_add(&zwplug->bio_list, bio); } /* * Called from bio_attempt_back_merge() when a BIO was merged with a request. */ void blk_zone_write_plug_bio_merged(struct bio *bio) { struct blk_zone_wplug *zwplug; unsigned long flags; /* * If the BIO was already plugged, then we were called through * blk_zone_write_plug_init_request() -> blk_attempt_bio_merge(). * For this case, we already hold a reference on the zone write plug for * the BIO and blk_zone_write_plug_init_request() will handle the * zone write pointer offset update. */ if (bio_flagged(bio, BIO_ZONE_WRITE_PLUGGING)) return; bio_set_flag(bio, BIO_ZONE_WRITE_PLUGGING); /* * Get a reference on the zone write plug of the target zone and advance * the zone write pointer offset. Given that this is a merge, we already * have at least one request and one BIO referencing the zone write * plug. So this should not fail. */ zwplug = disk_get_zone_wplug(bio->bi_bdev->bd_disk, bio->bi_iter.bi_sector); if (WARN_ON_ONCE(!zwplug)) return; spin_lock_irqsave(&zwplug->lock, flags); zwplug->wp_offset += bio_sectors(bio); spin_unlock_irqrestore(&zwplug->lock, flags); } /* * Attempt to merge plugged BIOs with a newly prepared request for a BIO that * already went through zone write plugging (either a new BIO or one that was * unplugged). */ void blk_zone_write_plug_init_request(struct request *req) { sector_t req_back_sector = blk_rq_pos(req) + blk_rq_sectors(req); struct request_queue *q = req->q; struct gendisk *disk = q->disk; unsigned int zone_capacity = disk->zone_capacity; struct blk_zone_wplug *zwplug = disk_get_zone_wplug(disk, blk_rq_pos(req)); unsigned long flags; struct bio *bio; if (WARN_ON_ONCE(!zwplug)) return; /* * Indicate that completion of this request needs to be handled with * blk_zone_write_plug_finish_request(), which will drop the reference * on the zone write plug we took above on entry to this function. */ req->rq_flags |= RQF_ZONE_WRITE_PLUGGING; if (blk_queue_nomerges(q)) return; /* * Walk through the list of plugged BIOs to check if they can be merged * into the back of the request. */ spin_lock_irqsave(&zwplug->lock, flags); while (zwplug->wp_offset < zone_capacity) { bio = bio_list_peek(&zwplug->bio_list); if (!bio) break; if (bio->bi_iter.bi_sector != req_back_sector || !blk_rq_merge_ok(req, bio)) break; WARN_ON_ONCE(bio_op(bio) != REQ_OP_WRITE_ZEROES && !bio->__bi_nr_segments); bio_list_pop(&zwplug->bio_list); if (bio_attempt_back_merge(req, bio, bio->__bi_nr_segments) != BIO_MERGE_OK) { bio_list_add_head(&zwplug->bio_list, bio); break; } /* * Drop the extra reference on the queue usage we got when * plugging the BIO and advance the write pointer offset. */ blk_queue_exit(q); zwplug->wp_offset += bio_sectors(bio); req_back_sector += bio_sectors(bio); } spin_unlock_irqrestore(&zwplug->lock, flags); } /* * Check and prepare a BIO for submission by incrementing the write pointer * offset of its zone write plug and changing zone append operations into * regular write when zone append emulation is needed. */ static bool blk_zone_wplug_prepare_bio(struct blk_zone_wplug *zwplug, struct bio *bio) { struct gendisk *disk = bio->bi_bdev->bd_disk; /* * Check that the user is not attempting to write to a full zone. * We know such BIO will fail, and that would potentially overflow our * write pointer offset beyond the end of the zone. */ if (zwplug->wp_offset >= disk->zone_capacity) goto err; if (bio_op(bio) == REQ_OP_ZONE_APPEND) { /* * Use a regular write starting at the current write pointer. * Similarly to native zone append operations, do not allow * merging. */ bio->bi_opf &= ~REQ_OP_MASK; bio->bi_opf |= REQ_OP_WRITE | REQ_NOMERGE; bio->bi_iter.bi_sector += zwplug->wp_offset; /* * Remember that this BIO is in fact a zone append operation * so that we can restore its operation code on completion. */ bio_set_flag(bio, BIO_EMULATES_ZONE_APPEND); } else { /* * Check for non-sequential writes early because we avoid a * whole lot of error handling trouble if we don't send it off * to the driver. */ if (bio_offset_from_zone_start(bio) != zwplug->wp_offset) goto err; } /* Advance the zone write pointer offset. */ zwplug->wp_offset += bio_sectors(bio); return true; err: /* We detected an invalid write BIO: schedule error recovery. */ disk_zone_wplug_set_error(disk, zwplug); kblockd_schedule_work(&disk->zone_wplugs_work); return false; } static bool blk_zone_wplug_handle_write(struct bio *bio, unsigned int nr_segs) { struct gendisk *disk = bio->bi_bdev->bd_disk; sector_t sector = bio->bi_iter.bi_sector; struct blk_zone_wplug *zwplug; gfp_t gfp_mask = GFP_NOIO; unsigned long flags; /* * BIOs must be fully contained within a zone so that we use the correct * zone write plug for the entire BIO. For blk-mq devices, the block * layer should already have done any splitting required to ensure this * and this BIO should thus not be straddling zone boundaries. For * BIO-based devices, it is the responsibility of the driver to split * the bio before submitting it. */ if (WARN_ON_ONCE(bio_straddles_zones(bio))) { bio_io_error(bio); return true; } /* Conventional zones do not need write plugging. */ if (disk_zone_is_conv(disk, sector)) { /* Zone append to conventional zones is not allowed. */ if (bio_op(bio) == REQ_OP_ZONE_APPEND) { bio_io_error(bio); return true; } return false; } if (bio->bi_opf & REQ_NOWAIT) gfp_mask = GFP_NOWAIT; zwplug = disk_get_and_lock_zone_wplug(disk, sector, gfp_mask, &flags); if (!zwplug) { bio_io_error(bio); return true; } /* Indicate that this BIO is being handled using zone write plugging. */ bio_set_flag(bio, BIO_ZONE_WRITE_PLUGGING); /* * If the zone is already plugged or has a pending error, add the BIO * to the plug BIO list. Otherwise, plug and let the BIO execute. */ if (zwplug->flags & BLK_ZONE_WPLUG_BUSY) goto plug; /* * If an error is detected when preparing the BIO, add it to the BIO * list so that error recovery can deal with it. */ if (!blk_zone_wplug_prepare_bio(zwplug, bio)) goto plug; zwplug->flags |= BLK_ZONE_WPLUG_PLUGGED; spin_unlock_irqrestore(&zwplug->lock, flags); return false; plug: zwplug->flags |= BLK_ZONE_WPLUG_PLUGGED; blk_zone_wplug_add_bio(zwplug, bio, nr_segs); spin_unlock_irqrestore(&zwplug->lock, flags); return true; } /** * blk_zone_plug_bio - Handle a zone write BIO with zone write plugging * @bio: The BIO being submitted * @nr_segs: The number of physical segments of @bio * * Handle write, write zeroes and zone append operations requiring emulation * using zone write plugging. * * Return true whenever @bio execution needs to be delayed through the zone * write plug. Otherwise, return false to let the submission path process * @bio normally. */ bool blk_zone_plug_bio(struct bio *bio, unsigned int nr_segs) { struct block_device *bdev = bio->bi_bdev; if (!bdev->bd_disk->zone_wplugs_hash) return false; /* * If the BIO already has the plugging flag set, then it was already * handled through this path and this is a submission from the zone * plug bio submit work. */ if (bio_flagged(bio, BIO_ZONE_WRITE_PLUGGING)) return false; /* * We do not need to do anything special for empty flush BIOs, e.g * BIOs such as issued by blkdev_issue_flush(). The is because it is * the responsibility of the user to first wait for the completion of * write operations for flush to have any effect on the persistence of * the written data. */ if (op_is_flush(bio->bi_opf) && !bio_sectors(bio)) return false; /* * Regular writes and write zeroes need to be handled through the target * zone write plug. This includes writes with REQ_FUA | REQ_PREFLUSH * which may need to go through the flush machinery depending on the * target device capabilities. Plugging such writes is fine as the flush * machinery operates at the request level, below the plug, and * completion of the flush sequence will go through the regular BIO * completion, which will handle zone write plugging. * Zone append operations for devices that requested emulation must * also be plugged so that these BIOs can be changed into regular * write BIOs. * Zone reset, reset all and finish commands need special treatment * to correctly track the write pointer offset of zones. These commands * are not plugged as we do not need serialization with write * operations. It is the responsibility of the user to not issue reset * and finish commands when write operations are in flight. */ switch (bio_op(bio)) { case REQ_OP_ZONE_APPEND: if (!bdev_emulates_zone_append(bdev)) return false; fallthrough; case REQ_OP_WRITE: case REQ_OP_WRITE_ZEROES: return blk_zone_wplug_handle_write(bio, nr_segs); case REQ_OP_ZONE_RESET: return blk_zone_wplug_handle_reset_or_finish(bio, 0); case REQ_OP_ZONE_FINISH: return blk_zone_wplug_handle_reset_or_finish(bio, bdev_zone_sectors(bdev)); case REQ_OP_ZONE_RESET_ALL: return blk_zone_wplug_handle_reset_all(bio); default: return false; } return false; } EXPORT_SYMBOL_GPL(blk_zone_plug_bio); static void disk_zone_wplug_schedule_bio_work(struct gendisk *disk, struct blk_zone_wplug *zwplug) { /* * Take a reference on the zone write plug and schedule the submission * of the next plugged BIO. blk_zone_wplug_bio_work() will release the * reference we take here. */ WARN_ON_ONCE(!(zwplug->flags & BLK_ZONE_WPLUG_PLUGGED)); atomic_inc(&zwplug->ref); queue_work(disk->zone_wplugs_wq, &zwplug->bio_work); } static void disk_zone_wplug_unplug_bio(struct gendisk *disk, struct blk_zone_wplug *zwplug) { unsigned long flags; spin_lock_irqsave(&zwplug->lock, flags); /* * If we had an error, schedule error recovery. The recovery work * will restart submission of plugged BIOs. */ if (zwplug->flags & BLK_ZONE_WPLUG_ERROR) { spin_unlock_irqrestore(&zwplug->lock, flags); kblockd_schedule_work(&disk->zone_wplugs_work); return; } /* Schedule submission of the next plugged BIO if we have one. */ if (!bio_list_empty(&zwplug->bio_list)) { disk_zone_wplug_schedule_bio_work(disk, zwplug); spin_unlock_irqrestore(&zwplug->lock, flags); return; } zwplug->flags &= ~BLK_ZONE_WPLUG_PLUGGED; /* * If the zone is full (it was fully written or finished, or empty * (it was reset), remove its zone write plug from the hash table. */ if (disk_should_remove_zone_wplug(disk, zwplug)) disk_remove_zone_wplug(disk, zwplug); spin_unlock_irqrestore(&zwplug->lock, flags); } void blk_zone_write_plug_bio_endio(struct bio *bio) { struct gendisk *disk = bio->bi_bdev->bd_disk; struct blk_zone_wplug *zwplug = disk_get_zone_wplug(disk, bio->bi_iter.bi_sector); unsigned long flags; if (WARN_ON_ONCE(!zwplug)) return; /* Make sure we do not see this BIO again by clearing the plug flag. */ bio_clear_flag(bio, BIO_ZONE_WRITE_PLUGGING); /* * If this is a regular write emulating a zone append operation, * restore the original operation code. */ if (bio_flagged(bio, BIO_EMULATES_ZONE_APPEND)) { bio->bi_opf &= ~REQ_OP_MASK; bio->bi_opf |= REQ_OP_ZONE_APPEND; } /* * If the BIO failed, mark the plug as having an error to trigger * recovery. */ if (bio->bi_status != BLK_STS_OK) { spin_lock_irqsave(&zwplug->lock, flags); disk_zone_wplug_set_error(disk, zwplug); spin_unlock_irqrestore(&zwplug->lock, flags); } /* Drop the reference we took when the BIO was issued. */ disk_put_zone_wplug(zwplug); /* * For BIO-based devices, blk_zone_write_plug_finish_request() * is not called. So we need to schedule execution of the next * plugged BIO here. */ if (bio->bi_bdev->bd_has_submit_bio) disk_zone_wplug_unplug_bio(disk, zwplug); /* Drop the reference we took when entering this function. */ disk_put_zone_wplug(zwplug); } void blk_zone_write_plug_finish_request(struct request *req) { struct gendisk *disk = req->q->disk; struct blk_zone_wplug *zwplug; zwplug = disk_get_zone_wplug(disk, req->__sector); if (WARN_ON_ONCE(!zwplug)) return; req->rq_flags &= ~RQF_ZONE_WRITE_PLUGGING; /* * Drop the reference we took when the request was initialized in * blk_zone_write_plug_init_request(). */ disk_put_zone_wplug(zwplug); disk_zone_wplug_unplug_bio(disk, zwplug); /* Drop the reference we took when entering this function. */ disk_put_zone_wplug(zwplug); } static void blk_zone_wplug_bio_work(struct work_struct *work) { struct blk_zone_wplug *zwplug = container_of(work, struct blk_zone_wplug, bio_work); struct block_device *bdev; unsigned long flags; struct bio *bio; /* * Submit the next plugged BIO. If we do not have any, clear * the plugged flag. */ spin_lock_irqsave(&zwplug->lock, flags); bio = bio_list_pop(&zwplug->bio_list); if (!bio) { zwplug->flags &= ~BLK_ZONE_WPLUG_PLUGGED; spin_unlock_irqrestore(&zwplug->lock, flags); goto put_zwplug; } if (!blk_zone_wplug_prepare_bio(zwplug, bio)) { /* Error recovery will decide what to do with the BIO. */ bio_list_add_head(&zwplug->bio_list, bio); spin_unlock_irqrestore(&zwplug->lock, flags); goto put_zwplug; } spin_unlock_irqrestore(&zwplug->lock, flags); bdev = bio->bi_bdev; submit_bio_noacct_nocheck(bio); /* * blk-mq devices will reuse the extra reference on the request queue * usage counter we took when the BIO was plugged, but the submission * path for BIO-based devices will not do that. So drop this extra * reference here. */ if (bdev->bd_has_submit_bio) blk_queue_exit(bdev->bd_disk->queue); put_zwplug: /* Drop the reference we took in disk_zone_wplug_schedule_bio_work(). */ disk_put_zone_wplug(zwplug); } static unsigned int blk_zone_wp_offset(struct blk_zone *zone) { switch (zone->cond) { case BLK_ZONE_COND_IMP_OPEN: case BLK_ZONE_COND_EXP_OPEN: case BLK_ZONE_COND_CLOSED: return zone->wp - zone->start; case BLK_ZONE_COND_FULL: return zone->len; case BLK_ZONE_COND_EMPTY: return 0; case BLK_ZONE_COND_NOT_WP: case BLK_ZONE_COND_OFFLINE: case BLK_ZONE_COND_READONLY: default: /* * Conventional, offline and read-only zones do not have a valid * write pointer. */ return UINT_MAX; } } static int blk_zone_wplug_report_zone_cb(struct blk_zone *zone, unsigned int idx, void *data) { struct blk_zone *zonep = data; *zonep = *zone; return 0; } static void disk_zone_wplug_handle_error(struct gendisk *disk, struct blk_zone_wplug *zwplug) { sector_t zone_start_sector = bdev_zone_sectors(disk->part0) * zwplug->zone_no; unsigned int noio_flag; struct blk_zone zone; unsigned long flags; int ret; /* Get the current zone information from the device. */ noio_flag = memalloc_noio_save(); ret = disk->fops->report_zones(disk, zone_start_sector, 1, blk_zone_wplug_report_zone_cb, &zone); memalloc_noio_restore(noio_flag); spin_lock_irqsave(&zwplug->lock, flags); /* * A zone reset or finish may have cleared the error already. In such * case, do nothing as the report zones may have seen the "old" write * pointer value before the reset/finish operation completed. */ if (!(zwplug->flags & BLK_ZONE_WPLUG_ERROR)) goto unlock; zwplug->flags &= ~BLK_ZONE_WPLUG_ERROR; if (ret != 1) { /* * We failed to get the zone information, meaning that something * is likely really wrong with the device. Abort all remaining * plugged BIOs as otherwise we could endup waiting forever on * plugged BIOs to complete if there is a queue freeze on-going. */ disk_zone_wplug_abort(zwplug); goto unplug; } /* Update the zone write pointer offset. */ zwplug->wp_offset = blk_zone_wp_offset(&zone); disk_zone_wplug_abort_unaligned(disk, zwplug); /* Restart BIO submission if we still have any BIO left. */ if (!bio_list_empty(&zwplug->bio_list)) { disk_zone_wplug_schedule_bio_work(disk, zwplug); goto unlock; } unplug: zwplug->flags &= ~BLK_ZONE_WPLUG_PLUGGED; if (disk_should_remove_zone_wplug(disk, zwplug)) disk_remove_zone_wplug(disk, zwplug); unlock: spin_unlock_irqrestore(&zwplug->lock, flags); } static void disk_zone_wplugs_work(struct work_struct *work) { struct gendisk *disk = container_of(work, struct gendisk, zone_wplugs_work); struct blk_zone_wplug *zwplug; unsigned long flags; spin_lock_irqsave(&disk->zone_wplugs_lock, flags); while (!list_empty(&disk->zone_wplugs_err_list)) { zwplug = list_first_entry(&disk->zone_wplugs_err_list, struct blk_zone_wplug, link); list_del_init(&zwplug->link); spin_unlock_irqrestore(&disk->zone_wplugs_lock, flags); disk_zone_wplug_handle_error(disk, zwplug); disk_put_zone_wplug(zwplug); spin_lock_irqsave(&disk->zone_wplugs_lock, flags); } spin_unlock_irqrestore(&disk->zone_wplugs_lock, flags); } static inline unsigned int disk_zone_wplugs_hash_size(struct gendisk *disk) { return 1U << disk->zone_wplugs_hash_bits; } void disk_init_zone_resources(struct gendisk *disk) { spin_lock_init(&disk->zone_wplugs_lock); INIT_LIST_HEAD(&disk->zone_wplugs_err_list); INIT_WORK(&disk->zone_wplugs_work, disk_zone_wplugs_work); } /* * For the size of a disk zone write plug hash table, use the size of the * zone write plug mempool, which is the maximum of the disk open zones and * active zones limits. But do not exceed 4KB (512 hlist head entries), that is, * 9 bits. For a disk that has no limits, mempool size defaults to 128. */ #define BLK_ZONE_WPLUG_MAX_HASH_BITS 9 #define BLK_ZONE_WPLUG_DEFAULT_POOL_SIZE 128 static int disk_alloc_zone_resources(struct gendisk *disk, unsigned int pool_size) { unsigned int i; disk->zone_wplugs_hash_bits = min(ilog2(pool_size) + 1, BLK_ZONE_WPLUG_MAX_HASH_BITS); disk->zone_wplugs_hash = kcalloc(disk_zone_wplugs_hash_size(disk), sizeof(struct hlist_head), GFP_KERNEL); if (!disk->zone_wplugs_hash) return -ENOMEM; for (i = 0; i < disk_zone_wplugs_hash_size(disk); i++) INIT_HLIST_HEAD(&disk->zone_wplugs_hash[i]); disk->zone_wplugs_pool = mempool_create_kmalloc_pool(pool_size, sizeof(struct blk_zone_wplug)); if (!disk->zone_wplugs_pool) goto free_hash; disk->zone_wplugs_wq = alloc_workqueue("%s_zwplugs", WQ_MEM_RECLAIM | WQ_HIGHPRI, pool_size, disk->disk_name); if (!disk->zone_wplugs_wq) goto destroy_pool; return 0; destroy_pool: mempool_destroy(disk->zone_wplugs_pool); disk->zone_wplugs_pool = NULL; free_hash: kfree(disk->zone_wplugs_hash); disk->zone_wplugs_hash = NULL; disk->zone_wplugs_hash_bits = 0; return -ENOMEM; } static void disk_destroy_zone_wplugs_hash_table(struct gendisk *disk) { struct blk_zone_wplug *zwplug; unsigned int i; if (!disk->zone_wplugs_hash) return; /* Free all the zone write plugs we have. */ for (i = 0; i < disk_zone_wplugs_hash_size(disk); i++) { while (!hlist_empty(&disk->zone_wplugs_hash[i])) { zwplug = hlist_entry(disk->zone_wplugs_hash[i].first, struct blk_zone_wplug, node); atomic_inc(&zwplug->ref); disk_remove_zone_wplug(disk, zwplug); disk_put_zone_wplug(zwplug); } } kfree(disk->zone_wplugs_hash); disk->zone_wplugs_hash = NULL; disk->zone_wplugs_hash_bits = 0; } void disk_free_zone_resources(struct gendisk *disk) { cancel_work_sync(&disk->zone_wplugs_work); if (disk->zone_wplugs_wq) { destroy_workqueue(disk->zone_wplugs_wq); disk->zone_wplugs_wq = NULL; } disk_destroy_zone_wplugs_hash_table(disk); /* * Wait for the zone write plugs to be RCU-freed before * destorying the mempool. */ rcu_barrier(); mempool_destroy(disk->zone_wplugs_pool); disk->zone_wplugs_pool = NULL; kfree(disk->conv_zones_bitmap); disk->conv_zones_bitmap = NULL; disk->zone_capacity = 0; disk->nr_zones = 0; } static inline bool disk_need_zone_resources(struct gendisk *disk) { /* * All mq zoned devices need zone resources so that the block layer * can automatically handle write BIO plugging. BIO-based device drivers * (e.g. DM devices) are normally responsible for handling zone write * ordering and do not need zone resources, unless the driver requires * zone append emulation. */ return queue_is_mq(disk->queue) || queue_emulates_zone_append(disk->queue); } static int disk_revalidate_zone_resources(struct gendisk *disk, unsigned int nr_zones) { struct queue_limits *lim = &disk->queue->limits; unsigned int pool_size; if (!disk_need_zone_resources(disk)) return 0; /* * If the device has no limit on the maximum number of open and active * zones, use BLK_ZONE_WPLUG_DEFAULT_POOL_SIZE. */ pool_size = max(lim->max_open_zones, lim->max_active_zones); if (!pool_size) pool_size = min(BLK_ZONE_WPLUG_DEFAULT_POOL_SIZE, nr_zones); if (!disk->zone_wplugs_hash) return disk_alloc_zone_resources(disk, pool_size); return 0; } struct blk_revalidate_zone_args { struct gendisk *disk; unsigned long *conv_zones_bitmap; unsigned int nr_zones; unsigned int zone_capacity; sector_t sector; }; /* * Update the disk zone resources information and device queue limits. * The disk queue is frozen when this is executed. */ static int disk_update_zone_resources(struct gendisk *disk, struct blk_revalidate_zone_args *args) { struct request_queue *q = disk->queue; unsigned int nr_seq_zones, nr_conv_zones = 0; unsigned int pool_size; struct queue_limits lim; disk->nr_zones = args->nr_zones; disk->zone_capacity = args->zone_capacity; swap(disk->conv_zones_bitmap, args->conv_zones_bitmap); if (disk->conv_zones_bitmap) nr_conv_zones = bitmap_weight(disk->conv_zones_bitmap, disk->nr_zones); if (nr_conv_zones >= disk->nr_zones) { pr_warn("%s: Invalid number of conventional zones %u / %u\n", disk->disk_name, nr_conv_zones, disk->nr_zones); return -ENODEV; } if (!disk->zone_wplugs_pool) return 0; /* * If the device has no limit on the maximum number of open and active * zones, set its max open zone limit to the mempool size to indicate * to the user that there is a potential performance impact due to * dynamic zone write plug allocation when simultaneously writing to * more zones than the size of the mempool. */ lim = queue_limits_start_update(q); nr_seq_zones = disk->nr_zones - nr_conv_zones; pool_size = max(lim.max_open_zones, lim.max_active_zones); if (!pool_size) pool_size = min(BLK_ZONE_WPLUG_DEFAULT_POOL_SIZE, nr_seq_zones); mempool_resize(disk->zone_wplugs_pool, pool_size); if (!lim.max_open_zones && !lim.max_active_zones) { if (pool_size < nr_seq_zones) lim.max_open_zones = pool_size; else lim.max_open_zones = 0; } return queue_limits_commit_update(q, &lim); } static int blk_revalidate_conv_zone(struct blk_zone *zone, unsigned int idx, struct blk_revalidate_zone_args *args) { struct gendisk *disk = args->disk; struct request_queue *q = disk->queue; if (zone->capacity != zone->len) { pr_warn("%s: Invalid conventional zone capacity\n", disk->disk_name); return -ENODEV; } if (!disk_need_zone_resources(disk)) return 0; if (!args->conv_zones_bitmap) { args->conv_zones_bitmap = blk_alloc_zone_bitmap(q->node, args->nr_zones); if (!args->conv_zones_bitmap) return -ENOMEM; } set_bit(idx, args->conv_zones_bitmap); return 0; } static int blk_revalidate_seq_zone(struct blk_zone *zone, unsigned int idx, struct blk_revalidate_zone_args *args) { struct gendisk *disk = args->disk; struct blk_zone_wplug *zwplug; unsigned int wp_offset; unsigned long flags; /* * Remember the capacity of the first sequential zone and check * if it is constant for all zones. */ if (!args->zone_capacity) args->zone_capacity = zone->capacity; if (zone->capacity != args->zone_capacity) { pr_warn("%s: Invalid variable zone capacity\n", disk->disk_name); return -ENODEV; } /* * We need to track the write pointer of all zones that are not * empty nor full. So make sure we have a zone write plug for * such zone if the device has a zone write plug hash table. */ if (!disk->zone_wplugs_hash) return 0; wp_offset = blk_zone_wp_offset(zone); if (!wp_offset || wp_offset >= zone->capacity) return 0; zwplug = disk_get_and_lock_zone_wplug(disk, zone->wp, GFP_NOIO, &flags); if (!zwplug) return -ENOMEM; spin_unlock_irqrestore(&zwplug->lock, flags); disk_put_zone_wplug(zwplug); return 0; } /* * Helper function to check the validity of zones of a zoned block device. */ static int blk_revalidate_zone_cb(struct blk_zone *zone, unsigned int idx, void *data) { struct blk_revalidate_zone_args *args = data; struct gendisk *disk = args->disk; sector_t capacity = get_capacity(disk); sector_t zone_sectors = disk->queue->limits.chunk_sectors; int ret; /* Check for bad zones and holes in the zone report */ if (zone->start != args->sector) { pr_warn("%s: Zone gap at sectors %llu..%llu\n", disk->disk_name, args->sector, zone->start); return -ENODEV; } if (zone->start >= capacity || !zone->len) { pr_warn("%s: Invalid zone start %llu, length %llu\n", disk->disk_name, zone->start, zone->len); return -ENODEV; } /* * All zones must have the same size, with the exception on an eventual * smaller last zone. */ if (zone->start + zone->len < capacity) { if (zone->len != zone_sectors) { pr_warn("%s: Invalid zoned device with non constant zone size\n", disk->disk_name); return -ENODEV; } } else if (zone->len > zone_sectors) { pr_warn("%s: Invalid zoned device with larger last zone size\n", disk->disk_name); return -ENODEV; } if (!zone->capacity || zone->capacity > zone->len) { pr_warn("%s: Invalid zone capacity\n", disk->disk_name); return -ENODEV; } /* Check zone type */ switch (zone->type) { case BLK_ZONE_TYPE_CONVENTIONAL: ret = blk_revalidate_conv_zone(zone, idx, args); break; case BLK_ZONE_TYPE_SEQWRITE_REQ: ret = blk_revalidate_seq_zone(zone, idx, args); break; case BLK_ZONE_TYPE_SEQWRITE_PREF: default: pr_warn("%s: Invalid zone type 0x%x at sectors %llu\n", disk->disk_name, (int)zone->type, zone->start); ret = -ENODEV; } if (!ret) args->sector += zone->len; return ret; } /** * blk_revalidate_disk_zones - (re)allocate and initialize zone write plugs * @disk: Target disk * * Helper function for low-level device drivers to check, (re) allocate and * initialize resources used for managing zoned disks. This function should * normally be called by blk-mq based drivers when a zoned gendisk is probed * and when the zone configuration of the gendisk changes (e.g. after a format). * Before calling this function, the device driver must already have set the * device zone size (chunk_sector limit) and the max zone append limit. * BIO based drivers can also use this function as long as the device queue * can be safely frozen. */ int blk_revalidate_disk_zones(struct gendisk *disk) { struct request_queue *q = disk->queue; sector_t zone_sectors = q->limits.chunk_sectors; sector_t capacity = get_capacity(disk); struct blk_revalidate_zone_args args = { }; unsigned int noio_flag; int ret = -ENOMEM; if (WARN_ON_ONCE(!blk_queue_is_zoned(q))) return -EIO; if (!capacity) return -ENODEV; /* * Checks that the device driver indicated a valid zone size and that * the max zone append limit is set. */ if (!zone_sectors || !is_power_of_2(zone_sectors)) { pr_warn("%s: Invalid non power of two zone size (%llu)\n", disk->disk_name, zone_sectors); return -ENODEV; } if (!queue_max_zone_append_sectors(q)) { pr_warn("%s: Invalid 0 maximum zone append limit\n", disk->disk_name); return -ENODEV; } /* * Ensure that all memory allocations in this context are done as if * GFP_NOIO was specified. */ args.disk = disk; args.nr_zones = (capacity + zone_sectors - 1) >> ilog2(zone_sectors); noio_flag = memalloc_noio_save(); ret = disk_revalidate_zone_resources(disk, args.nr_zones); if (ret) { memalloc_noio_restore(noio_flag); return ret; } ret = disk->fops->report_zones(disk, 0, UINT_MAX, blk_revalidate_zone_cb, &args); if (!ret) { pr_warn("%s: No zones reported\n", disk->disk_name); ret = -ENODEV; } memalloc_noio_restore(noio_flag); /* * If zones where reported, make sure that the entire disk capacity * has been checked. */ if (ret > 0 && args.sector != capacity) { pr_warn("%s: Missing zones from sector %llu\n", disk->disk_name, args.sector); ret = -ENODEV; } /* * Set the new disk zone parameters only once the queue is frozen and * all I/Os are completed. */ blk_mq_freeze_queue(q); if (ret > 0) ret = disk_update_zone_resources(disk, &args); else pr_warn("%s: failed to revalidate zones\n", disk->disk_name); if (ret) disk_free_zone_resources(disk); blk_mq_unfreeze_queue(q); kfree(args.conv_zones_bitmap); return ret; } EXPORT_SYMBOL_GPL(blk_revalidate_disk_zones); #ifdef CONFIG_BLK_DEBUG_FS int queue_zone_wplugs_show(void *data, struct seq_file *m) { struct request_queue *q = data; struct gendisk *disk = q->disk; struct blk_zone_wplug *zwplug; unsigned int zwp_wp_offset, zwp_flags; unsigned int zwp_zone_no, zwp_ref; unsigned int zwp_bio_list_size, i; unsigned long flags; if (!disk->zone_wplugs_hash) return 0; rcu_read_lock(); for (i = 0; i < disk_zone_wplugs_hash_size(disk); i++) { hlist_for_each_entry_rcu(zwplug, &disk->zone_wplugs_hash[i], node) { spin_lock_irqsave(&zwplug->lock, flags); zwp_zone_no = zwplug->zone_no; zwp_flags = zwplug->flags; zwp_ref = atomic_read(&zwplug->ref); zwp_wp_offset = zwplug->wp_offset; zwp_bio_list_size = bio_list_size(&zwplug->bio_list); spin_unlock_irqrestore(&zwplug->lock, flags); seq_printf(m, "%u 0x%x %u %u %u\n", zwp_zone_no, zwp_flags, zwp_ref, zwp_wp_offset, zwp_bio_list_size); } } rcu_read_unlock(); return 0; } #endif