diff --git a/block/blk-integrity.c b/block/blk-integrity.c index 54bcba6c02a7..129b9e209a3b 100644 --- a/block/blk-integrity.c +++ b/block/blk-integrity.c @@ -30,6 +30,8 @@ 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 @@ -358,6 +360,14 @@ static struct kobj_type integrity_ktype = { .release = blk_integrity_release, }; +bool blk_integrity_is_initialized(struct gendisk *disk) +{ + struct blk_integrity *bi = blk_get_integrity(disk); + + return (bi && bi->name && strcmp(bi->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 @@ -407,7 +417,7 @@ int blk_integrity_register(struct gendisk *disk, struct blk_integrity *template) bi->get_tag_fn = template->get_tag_fn; bi->tag_size = template->tag_size; } else - bi->name = "unsupported"; + bi->name = bi_unsupported_name; return 0; } diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 416d4e258df6..cb8380c9767f 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -926,21 +926,81 @@ static int dm_table_build_index(struct dm_table *t) return r; } +/* + * 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) +{ + struct list_head *devices = dm_table_get_devices(t); + struct dm_dev_internal *dd = NULL; + struct gendisk *prev_disk = NULL, *template_disk = NULL; + + list_for_each_entry(dd, devices, list) { + template_disk = dd->dm_dev.bdev->bd_disk; + if (!blk_get_integrity(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; + prev_disk = template_disk; + } + + return template_disk; + +no_integrity: + if (prev_disk) + DMWARN("%s: integrity not set: %s and %s profile mismatch", + dm_device_name(t->md), + prev_disk->disk_name, + template_disk->disk_name); + return NULL; +} + /* * Register the mapped device for blk_integrity support if - * the underlying devices support it. + * 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 */ static int dm_table_prealloc_integrity(struct dm_table *t, struct mapped_device *md) { - struct list_head *devices = dm_table_get_devices(t); - struct dm_dev_internal *dd; + struct gendisk *template_disk = NULL; - list_for_each_entry(dd, devices, list) - if (bdev_get_integrity(dd->dm_dev.bdev)) { - t->integrity_supported = 1; - return blk_integrity_register(dm_disk(md), NULL); - } + template_disk = dm_table_get_integrity_disk(t, false); + if (!template_disk) + return 0; + if (!blk_integrity_is_initialized(dm_disk(md))) { + t->integrity_supported = 1; + return blk_integrity_register(dm_disk(md), NULL); + } + + /* + * If DM device already has an initalized integrity + * profile the new profile should not conflict. + */ + if (blk_integrity_is_initialized(template_disk) && + blk_integrity_compare(dm_disk(md), template_disk) < 0) { + DMWARN("%s: conflict with existing integrity profile: " + "%s profile mismatch", + dm_device_name(t->md), + template_disk->disk_name); + return 1; + } + + /* Preserve existing initialized integrity profile */ + t->integrity_supported = 1; return 0; } @@ -1094,41 +1154,27 @@ combine_limits: /* * Set the integrity profile for this device if all devices used have - * matching profiles. + * 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. */ static void dm_table_set_integrity(struct dm_table *t) { - struct list_head *devices = dm_table_get_devices(t); - struct dm_dev_internal *prev = NULL, *dd = NULL; + struct gendisk *template_disk = NULL; if (!blk_get_integrity(dm_disk(t->md))) return; - list_for_each_entry(dd, devices, list) { - if (prev && - blk_integrity_compare(prev->dm_dev.bdev->bd_disk, - dd->dm_dev.bdev->bd_disk) < 0) { - DMWARN("%s: integrity not set: %s and %s mismatch", - dm_device_name(t->md), - prev->dm_dev.bdev->bd_disk->disk_name, - dd->dm_dev.bdev->bd_disk->disk_name); - goto no_integrity; - } - prev = dd; + template_disk = dm_table_get_integrity_disk(t, true); + if (!template_disk && + blk_integrity_is_initialized(dm_disk(t->md))) { + DMWARN("%s: device no longer has a valid integrity profile", + dm_device_name(t->md)); + return; } - - if (!prev || !bdev_get_integrity(prev->dm_dev.bdev)) - goto no_integrity; - blk_integrity_register(dm_disk(t->md), - bdev_get_integrity(prev->dm_dev.bdev)); - - return; - -no_integrity: - blk_integrity_register(dm_disk(t->md), NULL); - - return; + blk_get_integrity(template_disk)); } void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 16a902f099ac..32176cc8e715 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1206,6 +1206,7 @@ struct blk_integrity { struct kobject kobj; }; +extern bool blk_integrity_is_initialized(struct gendisk *); extern int blk_integrity_register(struct gendisk *, struct blk_integrity *); extern void blk_integrity_unregister(struct gendisk *); extern int blk_integrity_compare(struct gendisk *, struct gendisk *); @@ -1262,6 +1263,7 @@ queue_max_integrity_segments(struct request_queue *q) #define queue_max_integrity_segments(a) (0) #define blk_integrity_merge_rq(a, b, c) (0) #define blk_integrity_merge_bio(a, b, c) (0) +#define blk_integrity_is_initialized(a) (0) #endif /* CONFIG_BLK_DEV_INTEGRITY */