diff options
| -rw-r--r-- | block/blk-integrity.c | 160 | ||||
| -rw-r--r-- | block/genhd.c | 2 | ||||
| -rw-r--r-- | block/partition-generic.c | 1 | ||||
| -rw-r--r-- | drivers/md/dm-table.c | 88 | ||||
| -rw-r--r-- | drivers/md/md.c | 9 | ||||
| -rw-r--r-- | drivers/nvdimm/core.c | 6 | ||||
| -rw-r--r-- | drivers/nvme/host/pci.c | 5 | ||||
| -rw-r--r-- | fs/block_dev.c | 2 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 34 | ||||
| -rw-r--r-- | include/linux/genhd.h | 26 |
10 files changed, 152 insertions, 181 deletions
diff --git a/block/blk-integrity.c b/block/blk-integrity.c index 7a96f57ed195..4615a3386798 100644 --- a/block/blk-integrity.c +++ b/block/blk-integrity.c @@ -30,10 +30,6 @@ #include "blk.h" -static struct kmem_cache *integrity_cachep; - -static const char *bi_unsupported_name = "unsupported"; - /** * blk_rq_count_integrity_sg - Count number of integrity scatterlist elements * @q: request queue @@ -146,13 +142,13 @@ EXPORT_SYMBOL(blk_rq_map_integrity_sg); */ int blk_integrity_compare(struct gendisk *gd1, struct gendisk *gd2) { - struct blk_integrity *b1 = gd1->integrity; - struct blk_integrity *b2 = gd2->integrity; + struct blk_integrity *b1 = &gd1->integrity; + struct blk_integrity *b2 = &gd2->integrity; - if (!b1 && !b2) + if (!b1->profile && !b2->profile) return 0; - if (!b1 || !b2) + if (!b1->profile || !b2->profile) return -1; if (b1->interval_exp != b2->interval_exp) { @@ -163,21 +159,21 @@ int blk_integrity_compare(struct gendisk *gd1, struct gendisk *gd2) } if (b1->tuple_size != b2->tuple_size) { - printk(KERN_ERR "%s: %s/%s tuple sz %u != %u\n", __func__, + pr_err("%s: %s/%s tuple sz %u != %u\n", __func__, gd1->disk_name, gd2->disk_name, b1->tuple_size, b2->tuple_size); return -1; } if (b1->tag_size && b2->tag_size && (b1->tag_size != b2->tag_size)) { - printk(KERN_ERR "%s: %s/%s tag sz %u != %u\n", __func__, + pr_err("%s: %s/%s tag sz %u != %u\n", __func__, gd1->disk_name, gd2->disk_name, b1->tag_size, b2->tag_size); return -1; } if (b1->profile != b2->profile) { - printk(KERN_ERR "%s: %s/%s type %s != %s\n", __func__, + pr_err("%s: %s/%s type %s != %s\n", __func__, gd1->disk_name, gd2->disk_name, b1->profile->name, b2->profile->name); return -1; @@ -250,7 +246,7 @@ static ssize_t integrity_attr_show(struct kobject *kobj, struct attribute *attr, char *page) { struct gendisk *disk = container_of(kobj, struct gendisk, integrity_kobj); - struct blk_integrity *bi = blk_get_integrity(disk); + struct blk_integrity *bi = &disk->integrity; struct integrity_sysfs_entry *entry = container_of(attr, struct integrity_sysfs_entry, attr); @@ -262,7 +258,7 @@ static ssize_t integrity_attr_store(struct kobject *kobj, size_t count) { struct gendisk *disk = container_of(kobj, struct gendisk, integrity_kobj); - struct blk_integrity *bi = blk_get_integrity(disk); + struct blk_integrity *bi = &disk->integrity; struct integrity_sysfs_entry *entry = container_of(attr, struct integrity_sysfs_entry, attr); ssize_t ret = 0; @@ -275,7 +271,7 @@ static ssize_t integrity_attr_store(struct kobject *kobj, static ssize_t integrity_format_show(struct blk_integrity *bi, char *page) { - if (bi != NULL && bi->profile->name != NULL) + if (bi->profile && bi->profile->name) return sprintf(page, "%s\n", bi->profile->name); else return sprintf(page, "none\n"); @@ -283,18 +279,13 @@ static ssize_t integrity_format_show(struct blk_integrity *bi, char *page) static ssize_t integrity_tag_size_show(struct blk_integrity *bi, char *page) { - if (bi != NULL) - return sprintf(page, "%u\n", bi->tag_size); - else - return sprintf(page, "0\n"); + return sprintf(page, "%u\n", bi->tag_size); } static ssize_t integrity_interval_show(struct blk_integrity *bi, char *page) { - if (bi != NULL) - return sprintf(page, "%u\n", 1 << bi->interval_exp); - else - return sprintf(page, "0\n"); + return sprintf(page, "%u\n", + bi->interval_exp ? 1 << bi->interval_exp : 0); } static ssize_t integrity_verify_store(struct blk_integrity *bi, @@ -388,113 +379,78 @@ static const struct sysfs_ops integrity_ops = { .store = &integrity_attr_store, }; -static int __init blk_dev_integrity_init(void) -{ - integrity_cachep = kmem_cache_create("blkdev_integrity", - sizeof(struct blk_integrity), - 0, SLAB_PANIC, NULL); - return 0; -} -subsys_initcall(blk_dev_integrity_init); - -static void blk_integrity_release(struct kobject *kobj) -{ - struct gendisk *disk = container_of(kobj, struct gendisk, integrity_kobj); - struct blk_integrity *bi = blk_get_integrity(disk); - - kmem_cache_free(integrity_cachep, bi); -} - static struct kobj_type integrity_ktype = { .default_attrs = integrity_attrs, .sysfs_ops = &integrity_ops, - .release = blk_integrity_release, }; -bool blk_integrity_is_initialized(struct gendisk *disk) -{ - struct blk_integrity *bi = blk_get_integrity(disk); - - return (bi && bi->profile->name && strcmp(bi->profile->name, - bi_unsupported_name) != 0); -} -EXPORT_SYMBOL(blk_integrity_is_initialized); - /** * blk_integrity_register - Register a gendisk as being integrity-capable * @disk: struct gendisk pointer to make integrity-aware - * @template: optional integrity profile to register + * @template: block integrity profile to register * - * Description: When a device needs to advertise itself as being able - * to send/receive integrity metadata it must use this function to - * register the capability with the block layer. The template is a - * blk_integrity struct with values appropriate for the underlying - * hardware. If template is NULL the new profile is allocated but - * not filled out. See Documentation/block/data-integrity.txt. + * Description: When a device needs to advertise itself as being able to + * send/receive integrity metadata it must use this function to register + * the capability with the block layer. The template is a blk_integrity + * struct with values appropriate for the underlying hardware. See + * Documentation/block/data-integrity.txt. */ -int blk_integrity_register(struct gendisk *disk, struct blk_integrity *template) +void blk_integrity_register(struct gendisk *disk, struct blk_integrity *template) { - struct blk_integrity *bi; - - BUG_ON(disk == NULL); + struct blk_integrity *bi = &disk->integrity; - if (disk->integrity == NULL) { - bi = kmem_cache_alloc(integrity_cachep, - GFP_KERNEL | __GFP_ZERO); - if (!bi) - return -1; + bi->flags = BLK_INTEGRITY_VERIFY | BLK_INTEGRITY_GENERATE | + template->flags; + bi->interval_exp = ilog2(queue_logical_block_size(disk->queue)); + bi->profile = template->profile; + bi->tuple_size = template->tuple_size; + bi->tag_size = template->tag_size; - if (kobject_init_and_add(&disk->integrity_kobj, &integrity_ktype, - &disk_to_dev(disk)->kobj, - "%s", "integrity")) { - kmem_cache_free(integrity_cachep, bi); - return -1; - } - - kobject_uevent(&disk->integrity_kobj, KOBJ_ADD); - - bi->flags |= BLK_INTEGRITY_VERIFY | BLK_INTEGRITY_GENERATE; - bi->interval_exp = ilog2(queue_logical_block_size(disk->queue)); - disk->integrity = bi; - } else - bi = disk->integrity; - - /* Use the provided profile as template */ - if (template != NULL) { - bi->profile = template->profile; - bi->tuple_size = template->tuple_size; - bi->tag_size = template->tag_size; - bi->flags |= template->flags; - } else - bi->profile->name = bi_unsupported_name; - - disk->queue->backing_dev_info.capabilities |= BDI_CAP_STABLE_WRITES; - - return 0; + blk_integrity_revalidate(disk); } EXPORT_SYMBOL(blk_integrity_register); /** - * blk_integrity_unregister - Remove block integrity profile - * @disk: disk whose integrity profile to deallocate + * blk_integrity_unregister - Unregister block integrity profile + * @disk: disk whose integrity profile to unregister * - * Description: This function frees all memory used by the block - * integrity profile. To be called at device teardown. + * Description: This function unregisters the integrity capability from + * a block device. */ void blk_integrity_unregister(struct gendisk *disk) { - struct blk_integrity *bi; + blk_integrity_revalidate(disk); + memset(&disk->integrity, 0, sizeof(struct blk_integrity)); +} +EXPORT_SYMBOL(blk_integrity_unregister); - if (!disk || !disk->integrity) +void blk_integrity_revalidate(struct gendisk *disk) +{ + struct blk_integrity *bi = &disk->integrity; + + if (!(disk->flags & GENHD_FL_UP)) return; - disk->queue->backing_dev_info.capabilities &= ~BDI_CAP_STABLE_WRITES; + if (bi->profile) + disk->queue->backing_dev_info.capabilities |= + BDI_CAP_STABLE_WRITES; + else + disk->queue->backing_dev_info.capabilities &= + ~BDI_CAP_STABLE_WRITES; +} - bi = disk->integrity; +void blk_integrity_add(struct gendisk *disk) +{ + if (kobject_init_and_add(&disk->integrity_kobj, &integrity_ktype, + &disk_to_dev(disk)->kobj, "%s", "integrity")) + return; + kobject_uevent(&disk->integrity_kobj, KOBJ_ADD); +} + +void blk_integrity_del(struct gendisk *disk) +{ kobject_uevent(&disk->integrity_kobj, KOBJ_REMOVE); kobject_del(&disk->integrity_kobj); kobject_put(&disk->integrity_kobj); - disk->integrity = NULL; } -EXPORT_SYMBOL(blk_integrity_unregister); diff --git a/block/genhd.c b/block/genhd.c index 0c706f33a599..e5cafa51567c 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -630,6 +630,7 @@ void add_disk(struct gendisk *disk) WARN_ON(retval); disk_add_events(disk); + blk_integrity_add(disk); } EXPORT_SYMBOL(add_disk); @@ -638,6 +639,7 @@ void del_gendisk(struct gendisk *disk) struct disk_part_iter piter; struct hd_struct *part; + blk_integrity_del(disk); disk_del_events(disk); /* invalidate stuff */ diff --git a/block/partition-generic.c b/block/partition-generic.c index e7711133284e..3b030157ec85 100644 --- a/block/partition-generic.c +++ b/block/partition-generic.c @@ -428,6 +428,7 @@ rescan: if (disk->fops->revalidate_disk) disk->fops->revalidate_disk(disk); + blk_integrity_revalidate(disk); check_disk_size_change(disk, bdev); bdev->bd_invalidated = 0; if (!get_capacity(disk) || !(state = check_partition(disk, bdev))) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index e76ed003769e..061152a43730 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -1014,15 +1014,16 @@ static int dm_table_build_index(struct dm_table *t) return r; } +static bool integrity_profile_exists(struct gendisk *disk) +{ + return !!blk_get_integrity(disk); +} + /* * Get a disk whose integrity profile reflects the table's profile. - * If %match_all is true, all devices' profiles must match. - * If %match_all is false, all devices must at least have an - * allocated integrity profile; but uninitialized is ok. * Returns NULL if integrity support was inconsistent or unavailable. */ -static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t, - bool match_all) +static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t) { struct list_head *devices = dm_table_get_devices(t); struct dm_dev_internal *dd = NULL; @@ -1030,10 +1031,8 @@ static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t, list_for_each_entry(dd, devices, list) { template_disk = dd->dm_dev->bdev->bd_disk; - if (!blk_get_integrity(template_disk)) + if (!integrity_profile_exists(template_disk)) goto no_integrity; - if (!match_all && !blk_integrity_is_initialized(template_disk)) - continue; /* skip uninitialized profiles */ else if (prev_disk && blk_integrity_compare(prev_disk, template_disk) < 0) goto no_integrity; @@ -1052,34 +1051,40 @@ no_integrity: } /* - * Register the mapped device for blk_integrity support if - * the underlying devices have an integrity profile. But all devices - * may not have matching profiles (checking all devices isn't reliable + * Register the mapped device for blk_integrity support if the + * underlying devices have an integrity profile. But all devices may + * not have matching profiles (checking all devices isn't reliable * during table load because this table may use other DM device(s) which - * must be resumed before they will have an initialized integity profile). - * Stacked DM devices force a 2 stage integrity profile validation: - * 1 - during load, validate all initialized integrity profiles match - * 2 - during resume, validate all integrity profiles match + * must be resumed before they will have an initialized integity + * profile). Consequently, stacked DM devices force a 2 stage integrity + * profile validation: First pass during table load, final pass during + * resume. */ -static int dm_table_prealloc_integrity(struct dm_table *t, struct mapped_device *md) +static int dm_table_register_integrity(struct dm_table *t) { + struct mapped_device *md = t->md; struct gendisk *template_disk = NULL; - template_disk = dm_table_get_integrity_disk(t, false); + template_disk = dm_table_get_integrity_disk(t); if (!template_disk) return 0; - if (!blk_integrity_is_initialized(dm_disk(md))) { + if (!integrity_profile_exists(dm_disk(md))) { t->integrity_supported = 1; - return blk_integrity_register(dm_disk(md), NULL); + /* + * Register integrity profile during table load; we can do + * this because the final profile must match during resume. + */ + blk_integrity_register(dm_disk(md), + blk_get_integrity(template_disk)); + return 0; } /* - * If DM device already has an initalized integrity + * If DM device already has an initialized integrity * profile the new profile should not conflict. */ - if (blk_integrity_is_initialized(template_disk) && - blk_integrity_compare(dm_disk(md), template_disk) < 0) { + if (blk_integrity_compare(dm_disk(md), template_disk) < 0) { DMWARN("%s: conflict with existing integrity profile: " "%s profile mismatch", dm_device_name(t->md), @@ -1087,7 +1092,7 @@ static int dm_table_prealloc_integrity(struct dm_table *t, struct mapped_device return 1; } - /* Preserve existing initialized integrity profile */ + /* Preserve existing integrity profile */ t->integrity_supported = 1; return 0; } @@ -1112,7 +1117,7 @@ int dm_table_complete(struct dm_table *t) return r; } - r = dm_table_prealloc_integrity(t, t->md); + r = dm_table_register_integrity(t); if (r) { DMERR("could not register integrity profile."); return r; @@ -1278,29 +1283,30 @@ combine_limits: } /* - * Set the integrity profile for this device if all devices used have - * matching profiles. We're quite deep in the resume path but still - * don't know if all devices (particularly DM devices this device - * may be stacked on) have matching profiles. Even if the profiles - * don't match we have no way to fail (to resume) at this point. + * Verify that all devices have an integrity profile that matches the + * DM device's registered integrity profile. If the profiles don't + * match then unregister the DM device's integrity profile. */ -static void dm_table_set_integrity(struct dm_table *t) +static void dm_table_verify_integrity(struct dm_table *t) { struct gendisk *template_disk = NULL; - if (!blk_get_integrity(dm_disk(t->md))) - return; + if (t->integrity_supported) { + /* + * Verify that the original integrity profile + * matches all the devices in this table. + */ + template_disk = dm_table_get_integrity_disk(t); + if (template_disk && + blk_integrity_compare(dm_disk(t->md), template_disk) >= 0) + return; + } - template_disk = dm_table_get_integrity_disk(t, true); - if (template_disk) - blk_integrity_register(dm_disk(t->md), - blk_get_integrity(template_disk)); - else if (blk_integrity_is_initialized(dm_disk(t->md))) - DMWARN("%s: device no longer has a valid integrity profile", - dm_device_name(t->md)); - else + if (integrity_profile_exists(dm_disk(t->md))) { DMWARN("%s: unable to establish an integrity profile", dm_device_name(t->md)); + blk_integrity_unregister(dm_disk(t->md)); + } } static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev, @@ -1500,7 +1506,7 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, else queue_flag_set_unlocked(QUEUE_FLAG_NO_SG_MERGE, q); - dm_table_set_integrity(t); + dm_table_verify_integrity(t); /* * Determine whether or not this queue's I/O timings contribute diff --git a/drivers/md/md.c b/drivers/md/md.c index c702de18207a..2af9d590e1a0 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -1962,12 +1962,9 @@ int md_integrity_register(struct mddev *mddev) * All component devices are integrity capable and have matching * profiles, register the common profile for the md device. */ - if (blk_integrity_register(mddev->gendisk, - bdev_get_integrity(reference->bdev)) != 0) { - printk(KERN_ERR "md: failed to register integrity for %s\n", - mdname(mddev)); - return -EINVAL; - } + blk_integrity_register(mddev->gendisk, + bdev_get_integrity(reference->bdev)); + printk(KERN_NOTICE "md: data integrity enabled on %s\n", mdname(mddev)); if (bioset_integrity_create(mddev->bio_set, BIO_POOL_SIZE)) { printk(KERN_ERR "md: failed to create integrity pool for %s\n", diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c index 7df89b547ae1..e85848caf8d2 100644 --- a/drivers/nvdimm/core.c +++ b/drivers/nvdimm/core.c @@ -405,7 +405,6 @@ int nd_integrity_init(struct gendisk *disk, unsigned long meta_size) .generate_fn = nd_pi_nop_generate_verify, .verify_fn = nd_pi_nop_generate_verify, }; - int ret; if (meta_size == 0) return 0; @@ -414,10 +413,7 @@ int nd_integrity_init(struct gendisk *disk, unsigned long meta_size) bi.tuple_size = meta_size; bi.tag_size = meta_size; - ret = blk_integrity_register(disk, &bi); - if (ret) - return ret; - + blk_integrity_register(disk, &bi); blk_queue_max_integrity_segments(disk->queue, 1); return 0; diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 04e3d60a1e45..8d2aeaaa3895 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -538,7 +538,7 @@ static void nvme_dif_remap(struct request *req, virt = bip_get_seed(bip); phys = nvme_block_nr(ns, blk_rq_pos(req)); nlb = (blk_rq_bytes(req) >> ns->lba_shift); - ts = ns->disk->integrity->tuple_size; + ts = ns->disk->integrity.tuple_size; for (i = 0; i < nlb; i++, virt++, phys++) { pi = (struct t10_pi_tuple *)p; @@ -2044,8 +2044,7 @@ static int nvme_revalidate_disk(struct gendisk *disk) ns->pi_type = pi_type; blk_queue_logical_block_size(ns->queue, bs); - if (ns->ms && !blk_get_integrity(disk) && (disk->flags & GENHD_FL_UP) && - !ns->ext) + if (ns->ms && !ns->ext) nvme_init_integrity(ns); if (ns->ms && !(ns->ms == 8 && ns->pi_type) && !blk_get_integrity(disk)) diff --git a/fs/block_dev.c b/fs/block_dev.c index 073bb57adab1..0a793c7930eb 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -1075,7 +1075,7 @@ int revalidate_disk(struct gendisk *disk) if (disk->fops->revalidate_disk) ret = disk->fops->revalidate_disk(disk); - + blk_integrity_revalidate(disk); bdev = bdget_disk(disk, 0); if (!bdev) return ret; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 4f1968f15e30..60669c20190f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1468,16 +1468,7 @@ struct blk_integrity_profile { const char *name; }; -struct blk_integrity { - struct blk_integrity_profile *profile; - unsigned char flags; - unsigned char tuple_size; - unsigned char interval_exp; - unsigned char tag_size; -}; - -extern bool blk_integrity_is_initialized(struct gendisk *); -extern int blk_integrity_register(struct gendisk *, struct blk_integrity *); +extern void blk_integrity_register(struct gendisk *, struct blk_integrity *); extern void blk_integrity_unregister(struct gendisk *); extern int blk_integrity_compare(struct gendisk *, struct gendisk *); extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *, @@ -1488,15 +1479,20 @@ extern bool blk_integrity_merge_rq(struct request_queue *, struct request *, extern bool blk_integrity_merge_bio(struct request_queue *, struct request *, struct bio *); -static inline -struct blk_integrity *bdev_get_integrity(struct block_device *bdev) +static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) { - return bdev->bd_disk->integrity; + struct blk_integrity *bi = &disk->integrity; + + if (!bi->profile) + return NULL; + + return bi; } -static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) +static inline +struct blk_integrity *bdev_get_integrity(struct block_device *bdev) { - return disk->integrity; + return blk_get_integrity(bdev->bd_disk); } static inline bool blk_integrity_rq(struct request *rq) @@ -1570,10 +1566,9 @@ static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b) { return 0; } -static inline int blk_integrity_register(struct gendisk *d, +static inline void blk_integrity_register(struct gendisk *d, struct blk_integrity *b) { - return 0; } static inline void blk_integrity_unregister(struct gendisk *d) { @@ -1598,10 +1593,7 @@ static inline bool blk_integrity_merge_bio(struct request_queue *rq, { return true; } -static inline bool blk_integrity_is_initialized(struct gendisk *g) -{ - return 0; -} + static inline bool integrity_req_gap_back_merge(struct request *req, struct bio *next) { diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 9e6e0dfa97ad..82f4911e0ad8 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -163,6 +163,18 @@ struct disk_part_tbl { struct disk_events; +#if defined(CONFIG_BLK_DEV_INTEGRITY) + +struct blk_integrity { + struct blk_integrity_profile *profile; + unsigned char flags; + unsigned char tuple_size; + unsigned char interval_exp; + unsigned char tag_size; +}; + +#endif /* CONFIG_BLK_DEV_INTEGRITY */ + struct gendisk { /* major, first_minor and minors are input parameters only, * don't use directly. Use disk_devt() and disk_max_parts(). @@ -198,9 +210,9 @@ struct gendisk { atomic_t sync_io; /* RAID */ struct disk_events *ev; #ifdef CONFIG_BLK_DEV_INTEGRITY - struct blk_integrity *integrity; + struct blk_integrity integrity; struct kobject integrity_kobj; -#endif +#endif /* CONFIG_BLK_DEV_INTEGRITY */ int node_id; }; @@ -728,6 +740,16 @@ static inline void part_nr_sects_write(struct hd_struct *part, sector_t size) #endif } +#if defined(CONFIG_BLK_DEV_INTEGRITY) +extern void blk_integrity_add(struct gendisk *); +extern void blk_integrity_del(struct gendisk *); +extern void blk_integrity_revalidate(struct gendisk *); +#else /* CONFIG_BLK_DEV_INTEGRITY */ +static inline void blk_integrity_add(struct gendisk *disk) { } +static inline void blk_integrity_del(struct gendisk *disk) { } +static inline void blk_integrity_revalidate(struct gendisk *disk) { } +#endif /* CONFIG_BLK_DEV_INTEGRITY */ + #else /* CONFIG_BLOCK */ static inline void printk_all_partitions(void) { } |