diff options
Diffstat (limited to 'block')
-rw-r--r-- | block/blk-crypto.c | 1 | ||||
-rw-r--r-- | block/blk-mq.c | 109 | ||||
-rw-r--r-- | block/keyslot-manager.c | 175 |
3 files changed, 217 insertions, 68 deletions
diff --git a/block/blk-crypto.c b/block/blk-crypto.c index 09fcb18fa778..c5bdaafffa29 100644 --- a/block/blk-crypto.c +++ b/block/blk-crypto.c @@ -409,3 +409,4 @@ int blk_crypto_evict_key(struct request_queue *q, */ return blk_crypto_fallback_evict_key(key); } +EXPORT_SYMBOL_GPL(blk_crypto_evict_key); diff --git a/block/blk-mq.c b/block/blk-mq.c index f21d922ecfaf..d4d7c1caa439 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -41,7 +41,7 @@ #include "blk-mq-sched.h" #include "blk-rq-qos.h" -static DEFINE_PER_CPU(struct list_head, blk_cpu_done); +static DEFINE_PER_CPU(struct llist_head, blk_cpu_done); static void blk_mq_poll_stats_start(struct request_queue *q); static void blk_mq_poll_stats_fn(struct blk_stat_callback *cb); @@ -567,80 +567,29 @@ void blk_mq_end_request(struct request *rq, blk_status_t error) } EXPORT_SYMBOL(blk_mq_end_request); -/* - * Softirq action handler - move entries to local list and loop over them - * while passing them to the queue registered handler. - */ -static __latent_entropy void blk_done_softirq(struct softirq_action *h) +static void blk_complete_reqs(struct llist_head *list) { - struct list_head *cpu_list, local_list; - - local_irq_disable(); - cpu_list = this_cpu_ptr(&blk_cpu_done); - list_replace_init(cpu_list, &local_list); - local_irq_enable(); - - while (!list_empty(&local_list)) { - struct request *rq; + struct llist_node *entry = llist_reverse_order(llist_del_all(list)); + struct request *rq, *next; - rq = list_entry(local_list.next, struct request, ipi_list); - list_del_init(&rq->ipi_list); + llist_for_each_entry_safe(rq, next, entry, ipi_list) rq->q->mq_ops->complete(rq); - } } -static void blk_mq_trigger_softirq(struct request *rq) +static __latent_entropy void blk_done_softirq(struct softirq_action *h) { - struct list_head *list; - unsigned long flags; - - local_irq_save(flags); - list = this_cpu_ptr(&blk_cpu_done); - list_add_tail(&rq->ipi_list, list); - - /* - * If the list only contains our just added request, signal a raise of - * the softirq. If there are already entries there, someone already - * raised the irq but it hasn't run yet. - */ - if (list->next == &rq->ipi_list) - raise_softirq_irqoff(BLOCK_SOFTIRQ); - local_irq_restore(flags); + blk_complete_reqs(this_cpu_ptr(&blk_cpu_done)); } static int blk_softirq_cpu_dead(unsigned int cpu) { - /* - * If a CPU goes away, splice its entries to the current CPU - * and trigger a run of the softirq - */ - local_irq_disable(); - list_splice_init(&per_cpu(blk_cpu_done, cpu), - this_cpu_ptr(&blk_cpu_done)); - raise_softirq_irqoff(BLOCK_SOFTIRQ); - local_irq_enable(); - + blk_complete_reqs(&per_cpu(blk_cpu_done, cpu)); return 0; } - static void __blk_mq_complete_request_remote(void *data) { - struct request *rq = data; - - /* - * For most of single queue controllers, there is only one irq vector - * for handling I/O completion, and the only irq's affinity is set - * to all possible CPUs. On most of ARCHs, this affinity means the irq - * is handled on one specific CPU. - * - * So complete I/O requests in softirq context in case of single queue - * devices to avoid degrading I/O performance due to irqsoff latency. - */ - if (rq->q->nr_hw_queues == 1) - blk_mq_trigger_softirq(rq); - else - rq->q->mq_ops->complete(rq); + __raise_softirq_irqoff(BLOCK_SOFTIRQ); } static inline bool blk_mq_complete_need_ipi(struct request *rq) @@ -669,6 +618,30 @@ static inline bool blk_mq_complete_need_ipi(struct request *rq) return cpu_online(rq->mq_ctx->cpu); } +static void blk_mq_complete_send_ipi(struct request *rq) +{ + struct llist_head *list; + unsigned int cpu; + + cpu = rq->mq_ctx->cpu; + list = &per_cpu(blk_cpu_done, cpu); + if (llist_add(&rq->ipi_list, list)) { + INIT_CSD(&rq->csd, __blk_mq_complete_request_remote, rq); + smp_call_function_single_async(cpu, &rq->csd); + } +} + +static void blk_mq_raise_softirq(struct request *rq) +{ + struct llist_head *list; + + preempt_disable(); + list = this_cpu_ptr(&blk_cpu_done); + if (llist_add(&rq->ipi_list, list)) + raise_softirq(BLOCK_SOFTIRQ); + preempt_enable(); +} + bool blk_mq_complete_request_remote(struct request *rq) { WRITE_ONCE(rq->state, MQ_RQ_COMPLETE); @@ -681,15 +654,15 @@ bool blk_mq_complete_request_remote(struct request *rq) return false; if (blk_mq_complete_need_ipi(rq)) { - INIT_CSD(&rq->csd, __blk_mq_complete_request_remote, rq); - smp_call_function_single_async(rq->mq_ctx->cpu, &rq->csd); - } else { - if (rq->q->nr_hw_queues > 1) - return false; - blk_mq_trigger_softirq(rq); + blk_mq_complete_send_ipi(rq); + return true; } - return true; + if (rq->q->nr_hw_queues == 1) { + blk_mq_raise_softirq(rq); + return true; + } + return false; } EXPORT_SYMBOL_GPL(blk_mq_complete_request_remote); @@ -3957,7 +3930,7 @@ static int __init blk_mq_init(void) int i; for_each_possible_cpu(i) - INIT_LIST_HEAD(&per_cpu(blk_cpu_done, i)); + init_llist_head(&per_cpu(blk_cpu_done, i)); open_softirq(BLOCK_SOFTIRQ, blk_done_softirq); cpuhp_setup_state_nocalls(CPUHP_BLOCK_SOFTIRQ_DEAD, diff --git a/block/keyslot-manager.c b/block/keyslot-manager.c index 86f8195d8039..2c4a55bea6ca 100644 --- a/block/keyslot-manager.c +++ b/block/keyslot-manager.c @@ -29,6 +29,7 @@ #define pr_fmt(fmt) "blk-crypto: " fmt #include <linux/keyslot-manager.h> +#include <linux/device.h> #include <linux/atomic.h> #include <linux/mutex.h> #include <linux/pm_runtime.h> @@ -62,6 +63,11 @@ static inline void blk_ksm_hw_exit(struct blk_keyslot_manager *ksm) pm_runtime_put_sync(ksm->dev); } +static inline bool blk_ksm_is_passthrough(struct blk_keyslot_manager *ksm) +{ + return ksm->num_slots == 0; +} + /** * blk_ksm_init() - Initialize a keyslot manager * @ksm: The keyslot_manager to initialize. @@ -127,6 +133,34 @@ err_destroy_ksm: } EXPORT_SYMBOL_GPL(blk_ksm_init); +static void blk_ksm_destroy_callback(void *ksm) +{ + blk_ksm_destroy(ksm); +} + +/** + * devm_blk_ksm_init() - Resource-managed blk_ksm_init() + * @dev: The device which owns the blk_keyslot_manager. + * @ksm: The blk_keyslot_manager to initialize. + * @num_slots: The number of key slots to manage. + * + * Like blk_ksm_init(), but causes blk_ksm_destroy() to be called automatically + * on driver detach. + * + * Return: 0 on success, or else a negative error code. + */ +int devm_blk_ksm_init(struct device *dev, struct blk_keyslot_manager *ksm, + unsigned int num_slots) +{ + int err = blk_ksm_init(ksm, num_slots); + + if (err) + return err; + + return devm_add_action_or_reset(dev, blk_ksm_destroy_callback, ksm); +} +EXPORT_SYMBOL_GPL(devm_blk_ksm_init); + static inline struct hlist_head * blk_ksm_hash_bucket_for_key(struct blk_keyslot_manager *ksm, const struct blk_crypto_key *key) @@ -205,6 +239,10 @@ blk_status_t blk_ksm_get_slot_for_key(struct blk_keyslot_manager *ksm, int err; *slot_ptr = NULL; + + if (blk_ksm_is_passthrough(ksm)) + return BLK_STS_OK; + down_read(&ksm->lock); slot = blk_ksm_find_and_grab_keyslot(ksm, key); up_read(&ksm->lock); @@ -325,6 +363,16 @@ int blk_ksm_evict_key(struct blk_keyslot_manager *ksm, struct blk_ksm_keyslot *slot; int err = 0; + if (blk_ksm_is_passthrough(ksm)) { + if (ksm->ksm_ll_ops.keyslot_evict) { + blk_ksm_hw_enter(ksm); + err = ksm->ksm_ll_ops.keyslot_evict(ksm, key, -1); + blk_ksm_hw_exit(ksm); + return err; + } + return 0; + } + blk_ksm_hw_enter(ksm); slot = blk_ksm_find_keyslot(ksm, key); if (!slot) @@ -360,6 +408,9 @@ void blk_ksm_reprogram_all_keys(struct blk_keyslot_manager *ksm) { unsigned int slot; + if (blk_ksm_is_passthrough(ksm)) + return; + /* This is for device initialization, so don't resume the device */ down_write(&ksm->lock); for (slot = 0; slot < ksm->num_slots; slot++) { @@ -401,3 +452,127 @@ void blk_ksm_unregister(struct request_queue *q) { q->ksm = NULL; } + +/** + * blk_ksm_intersect_modes() - restrict supported modes by child device + * @parent: The keyslot manager for parent device + * @child: The keyslot manager for child device, or NULL + * + * Clear any crypto mode support bits in @parent that aren't set in @child. + * If @child is NULL, then all parent bits are cleared. + * + * Only use this when setting up the keyslot manager for a layered device, + * before it's been exposed yet. + */ +void blk_ksm_intersect_modes(struct blk_keyslot_manager *parent, + const struct blk_keyslot_manager *child) +{ + if (child) { + unsigned int i; + + parent->max_dun_bytes_supported = + min(parent->max_dun_bytes_supported, + child->max_dun_bytes_supported); + for (i = 0; i < ARRAY_SIZE(child->crypto_modes_supported); + i++) { + parent->crypto_modes_supported[i] &= + child->crypto_modes_supported[i]; + } + } else { + parent->max_dun_bytes_supported = 0; + memset(parent->crypto_modes_supported, 0, + sizeof(parent->crypto_modes_supported)); + } +} +EXPORT_SYMBOL_GPL(blk_ksm_intersect_modes); + +/** + * blk_ksm_is_superset() - Check if a KSM supports a superset of crypto modes + * and DUN bytes that another KSM supports. Here, + * "superset" refers to the mathematical meaning of the + * word - i.e. if two KSMs have the *same* capabilities, + * they *are* considered supersets of each other. + * @ksm_superset: The KSM that we want to verify is a superset + * @ksm_subset: The KSM that we want to verify is a subset + * + * Return: True if @ksm_superset supports a superset of the crypto modes and DUN + * bytes that @ksm_subset supports. + */ +bool blk_ksm_is_superset(struct blk_keyslot_manager *ksm_superset, + struct blk_keyslot_manager *ksm_subset) +{ + int i; + + if (!ksm_subset) + return true; + + if (!ksm_superset) + return false; + + for (i = 0; i < ARRAY_SIZE(ksm_superset->crypto_modes_supported); i++) { + if (ksm_subset->crypto_modes_supported[i] & + (~ksm_superset->crypto_modes_supported[i])) { + return false; + } + } + + if (ksm_subset->max_dun_bytes_supported > + ksm_superset->max_dun_bytes_supported) { + return false; + } + + return true; +} +EXPORT_SYMBOL_GPL(blk_ksm_is_superset); + +/** + * blk_ksm_update_capabilities() - Update the restrictions of a KSM to those of + * another KSM + * @target_ksm: The KSM whose restrictions to update. + * @reference_ksm: The KSM to whose restrictions this function will update + * @target_ksm's restrictions to. + * + * Blk-crypto requires that crypto capabilities that were + * advertised when a bio was created continue to be supported by the + * device until that bio is ended. This is turn means that a device cannot + * shrink its advertised crypto capabilities without any explicit + * synchronization with upper layers. So if there's no such explicit + * synchronization, @reference_ksm must support all the crypto capabilities that + * @target_ksm does + * (i.e. we need blk_ksm_is_superset(@reference_ksm, @target_ksm) == true). + * + * Note also that as long as the crypto capabilities are being expanded, the + * order of updates becoming visible is not important because it's alright + * for blk-crypto to see stale values - they only cause blk-crypto to + * believe that a crypto capability isn't supported when it actually is (which + * might result in blk-crypto-fallback being used if available, or the bio being + * failed). + */ +void blk_ksm_update_capabilities(struct blk_keyslot_manager *target_ksm, + struct blk_keyslot_manager *reference_ksm) +{ + memcpy(target_ksm->crypto_modes_supported, + reference_ksm->crypto_modes_supported, + sizeof(target_ksm->crypto_modes_supported)); + + target_ksm->max_dun_bytes_supported = + reference_ksm->max_dun_bytes_supported; +} +EXPORT_SYMBOL_GPL(blk_ksm_update_capabilities); + +/** + * blk_ksm_init_passthrough() - Init a passthrough keyslot manager + * @ksm: The keyslot manager to init + * + * Initialize a passthrough keyslot manager. + * Called by e.g. storage drivers to set up a keyslot manager in their + * request_queue, when the storage driver wants to manage its keys by itself. + * This is useful for inline encryption hardware that doesn't have the concept + * of keyslots, and for layered devices. + */ +void blk_ksm_init_passthrough(struct blk_keyslot_manager *ksm) +{ + memset(ksm, 0, sizeof(*ksm)); + init_rwsem(&ksm->lock); +} +EXPORT_SYMBOL_GPL(blk_ksm_init_passthrough); |