From bb4c19e030f45c5416f1eb4daa94fbaf7165e9ea Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Mon, 27 Mar 2023 23:37:33 +0900 Subject: block: null_blk: make fault-injection dynamically configurable per device The null_blk driver has multiple driver-specific fault injection mechanisms. Each fault injection configuration can only be specified by a module parameter and cannot be reconfigured without reloading the driver. Also, each configuration is common to all devices and is initialized every time a new device is added. This change adds the following subdirectories for each null_blk device. /sys/kernel/config/nullb//timeout_inject /sys/kernel/config/nullb//requeue_inject /sys/kernel/config/nullb//init_hctx_fault_inject Each fault injection attribute can be dynamically set per device by a corresponding file in these directories. Signed-off-by: Akinobu Mita Link: https://lore.kernel.org/r/20230327143733.14599-3-akinobu.mita@gmail.com Signed-off-by: Jens Axboe --- drivers/block/null_blk/Kconfig | 2 +- drivers/block/null_blk/main.c | 93 ++++++++++++++++++++++++++++++--------- drivers/block/null_blk/null_blk.h | 7 ++- 3 files changed, 79 insertions(+), 23 deletions(-) (limited to 'drivers/block/null_blk') diff --git a/drivers/block/null_blk/Kconfig b/drivers/block/null_blk/Kconfig index 6bf1f8ca20a2..ff23bb9346d0 100644 --- a/drivers/block/null_blk/Kconfig +++ b/drivers/block/null_blk/Kconfig @@ -9,4 +9,4 @@ config BLK_DEV_NULL_BLK config BLK_DEV_NULL_BLK_FAULT_INJECTION bool "Support fault injection for Null test block driver" - depends on BLK_DEV_NULL_BLK && FAULT_INJECTION + depends on BLK_DEV_NULL_BLK && FAULT_INJECTION_CONFIGFS diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c index 1d914a82f863..9a7e5699369e 100644 --- a/drivers/block/null_blk/main.c +++ b/drivers/block/null_blk/main.c @@ -250,7 +250,7 @@ static void null_free_device_storage(struct nullb_device *dev, bool is_cache); static inline struct nullb_device *to_nullb_device(struct config_item *item) { - return item ? container_of(item, struct nullb_device, item) : NULL; + return item ? container_of(to_config_group(item), struct nullb_device, group) : NULL; } static inline ssize_t nullb_device_uint_attr_show(unsigned int val, char *page) @@ -593,8 +593,29 @@ static const struct config_item_type nullb_device_type = { .ct_owner = THIS_MODULE, }; +#ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION + +static void nullb_add_fault_config(struct nullb_device *dev) +{ + fault_config_init(&dev->timeout_config, "timeout_inject"); + fault_config_init(&dev->requeue_config, "requeue_inject"); + fault_config_init(&dev->init_hctx_fault_config, "init_hctx_fault_inject"); + + configfs_add_default_group(&dev->timeout_config.group, &dev->group); + configfs_add_default_group(&dev->requeue_config.group, &dev->group); + configfs_add_default_group(&dev->init_hctx_fault_config.group, &dev->group); +} + +#else + +static void nullb_add_fault_config(struct nullb_device *dev) +{ +} + +#endif + static struct -config_item *nullb_group_make_item(struct config_group *group, const char *name) +config_group *nullb_group_make_group(struct config_group *group, const char *name) { struct nullb_device *dev; @@ -605,9 +626,10 @@ config_item *nullb_group_make_item(struct config_group *group, const char *name) if (!dev) return ERR_PTR(-ENOMEM); - config_item_init_type_name(&dev->item, name, &nullb_device_type); + config_group_init_type_name(&dev->group, name, &nullb_device_type); + nullb_add_fault_config(dev); - return &dev->item; + return &dev->group; } static void @@ -645,7 +667,7 @@ static struct configfs_attribute *nullb_group_attrs[] = { }; static struct configfs_group_operations nullb_group_ops = { - .make_item = nullb_group_make_item, + .make_group = nullb_group_make_group, .drop_item = nullb_group_drop_item, }; @@ -676,6 +698,13 @@ static struct nullb_device *null_alloc_dev(void) dev = kzalloc(sizeof(*dev), GFP_KERNEL); if (!dev) return NULL; + +#ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION + dev->timeout_config.attr = null_timeout_attr; + dev->requeue_config.attr = null_requeue_attr; + dev->init_hctx_fault_config.attr = null_init_hctx_attr; +#endif + INIT_RADIX_TREE(&dev->data, GFP_ATOMIC); INIT_RADIX_TREE(&dev->cache, GFP_ATOMIC); if (badblocks_init(&dev->badblocks, 0)) { @@ -1515,24 +1544,48 @@ static void null_submit_bio(struct bio *bio) null_handle_cmd(alloc_cmd(nq, bio), sector, nr_sectors, bio_op(bio)); } +#ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION + +static bool should_timeout_request(struct request *rq) +{ + struct nullb_cmd *cmd = blk_mq_rq_to_pdu(rq); + struct nullb_device *dev = cmd->nq->dev; + + return should_fail(&dev->timeout_config.attr, 1); +} + +static bool should_requeue_request(struct request *rq) +{ + struct nullb_cmd *cmd = blk_mq_rq_to_pdu(rq); + struct nullb_device *dev = cmd->nq->dev; + + return should_fail(&dev->requeue_config.attr, 1); +} + +static bool should_init_hctx_fail(struct nullb_device *dev) +{ + return should_fail(&dev->init_hctx_fault_config.attr, 1); +} + +#else + static bool should_timeout_request(struct request *rq) { -#ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION - if (g_timeout_str[0]) - return should_fail(&null_timeout_attr, 1); -#endif return false; } static bool should_requeue_request(struct request *rq) { -#ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION - if (g_requeue_str[0]) - return should_fail(&null_requeue_attr, 1); -#endif return false; } +static bool should_init_hctx_fail(struct nullb_device *dev) +{ + return false; +} + +#endif + static void null_map_queues(struct blk_mq_tag_set *set) { struct nullb *nullb = set->driver_data; @@ -1729,10 +1782,8 @@ static int null_init_hctx(struct blk_mq_hw_ctx *hctx, void *driver_data, struct nullb *nullb = hctx->queue->queuedata; struct nullb_queue *nq; -#ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION - if (g_init_hctx_str[0] && should_fail(&null_init_hctx_attr, 1)) + if (should_init_hctx_fail(nullb->dev)) return -EFAULT; -#endif nq = &nullb->queues[hctx_idx]; hctx->driver_data = nq; @@ -2052,9 +2103,6 @@ static int null_add_dev(struct nullb_device *dev) if (rv) goto out_cleanup_queues; - if (!null_setup_fault()) - goto out_cleanup_tags; - nullb->tag_set->timeout = 5 * HZ; nullb->disk = blk_mq_alloc_disk(nullb->tag_set, nullb); if (IS_ERR(nullb->disk)) { @@ -2116,10 +2164,10 @@ static int null_add_dev(struct nullb_device *dev) null_config_discard(nullb); - if (config_item_name(&dev->item)) { + if (config_item_name(&dev->group.cg_item)) { /* Use configfs dir name as the device name */ snprintf(nullb->disk_name, sizeof(nullb->disk_name), - "%s", config_item_name(&dev->item)); + "%s", config_item_name(&dev->group.cg_item)); } else { sprintf(nullb->disk_name, "nullb%d", nullb->index); } @@ -2219,6 +2267,9 @@ static int __init null_init(void) g_home_node = NUMA_NO_NODE; } + if (!null_setup_fault()) + return -EINVAL; + if (g_queue_mode == NULL_Q_RQ) { pr_err("legacy IO path is no longer available\n"); return -EINVAL; diff --git a/drivers/block/null_blk/null_blk.h b/drivers/block/null_blk/null_blk.h index eb5972c50be8..929f659dd255 100644 --- a/drivers/block/null_blk/null_blk.h +++ b/drivers/block/null_blk/null_blk.h @@ -69,7 +69,12 @@ enum { struct nullb_device { struct nullb *nullb; - struct config_item item; + struct config_group group; +#ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION + struct fault_config timeout_config; + struct fault_config requeue_config; + struct fault_config init_hctx_fault_config; +#endif struct radix_tree_root data; /* data stored in the disk */ struct radix_tree_root cache; /* disk cache data */ unsigned long flags; /* device flags */ -- cgit v1.2.3