diff options
Diffstat (limited to 'drivers/nvme/target/core.c')
| -rw-r--r-- | drivers/nvme/target/core.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c index 0acdff9e6842..f4efe289dc7b 100644 --- a/drivers/nvme/target/core.c +++ b/drivers/nvme/target/core.c @@ -15,6 +15,7 @@ #include <linux/module.h> #include <linux/random.h> #include <linux/rculist.h> +#include <linux/pci-p2pdma.h> #include "nvmet.h" @@ -365,9 +366,93 @@ static void nvmet_ns_dev_disable(struct nvmet_ns *ns) nvmet_file_ns_disable(ns); } +static int nvmet_p2pmem_ns_enable(struct nvmet_ns *ns) +{ + int ret; + struct pci_dev *p2p_dev; + + if (!ns->use_p2pmem) + return 0; + + if (!ns->bdev) { + pr_err("peer-to-peer DMA is not supported by non-block device namespaces\n"); + return -EINVAL; + } + + if (!blk_queue_pci_p2pdma(ns->bdev->bd_queue)) { + pr_err("peer-to-peer DMA is not supported by the driver of %s\n", + ns->device_path); + return -EINVAL; + } + + if (ns->p2p_dev) { + ret = pci_p2pdma_distance(ns->p2p_dev, nvmet_ns_dev(ns), true); + if (ret < 0) + return -EINVAL; + } else { + /* + * Right now we just check that there is p2pmem available so + * we can report an error to the user right away if there + * is not. We'll find the actual device to use once we + * setup the controller when the port's device is available. + */ + + p2p_dev = pci_p2pmem_find(nvmet_ns_dev(ns)); + if (!p2p_dev) { + pr_err("no peer-to-peer memory is available for %s\n", + ns->device_path); + return -EINVAL; + } + + pci_dev_put(p2p_dev); + } + + return 0; +} + +/* + * Note: ctrl->subsys->lock should be held when calling this function + */ +static void nvmet_p2pmem_ns_add_p2p(struct nvmet_ctrl *ctrl, + struct nvmet_ns *ns) +{ + struct device *clients[2]; + struct pci_dev *p2p_dev; + int ret; + + if (!ctrl->p2p_client) + return; + + if (ns->p2p_dev) { + ret = pci_p2pdma_distance(ns->p2p_dev, ctrl->p2p_client, true); + if (ret < 0) + return; + + p2p_dev = pci_dev_get(ns->p2p_dev); + } else { + clients[0] = ctrl->p2p_client; + clients[1] = nvmet_ns_dev(ns); + + p2p_dev = pci_p2pmem_find_many(clients, ARRAY_SIZE(clients)); + if (!p2p_dev) { + pr_err("no peer-to-peer memory is available that's supported by %s and %s\n", + dev_name(ctrl->p2p_client), ns->device_path); + return; + } + } + + ret = radix_tree_insert(&ctrl->p2p_ns_map, ns->nsid, p2p_dev); + if (ret < 0) + pci_dev_put(p2p_dev); + + pr_info("using p2pmem on %s for nsid %d\n", pci_name(p2p_dev), + ns->nsid); +} + int nvmet_ns_enable(struct nvmet_ns *ns) { struct nvmet_subsys *subsys = ns->subsys; + struct nvmet_ctrl *ctrl; int ret; mutex_lock(&subsys->lock); @@ -384,6 +469,13 @@ int nvmet_ns_enable(struct nvmet_ns *ns) if (ret) goto out_unlock; + ret = nvmet_p2pmem_ns_enable(ns); + if (ret) + goto out_unlock; + + list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) + nvmet_p2pmem_ns_add_p2p(ctrl, ns); + ret = percpu_ref_init(&ns->ref, nvmet_destroy_namespace, 0, GFP_KERNEL); if (ret) @@ -418,6 +510,9 @@ out_unlock: mutex_unlock(&subsys->lock); return ret; out_dev_put: + list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) + pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid)); + nvmet_ns_dev_disable(ns); goto out_unlock; } @@ -425,6 +520,7 @@ out_dev_put: void nvmet_ns_disable(struct nvmet_ns *ns) { struct nvmet_subsys *subsys = ns->subsys; + struct nvmet_ctrl *ctrl; mutex_lock(&subsys->lock); if (!ns->enabled) @@ -434,6 +530,10 @@ void nvmet_ns_disable(struct nvmet_ns *ns) list_del_rcu(&ns->dev_link); if (ns->nsid == subsys->max_nsid) subsys->max_nsid = nvmet_max_nsid(subsys); + + list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) + pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid)); + mutex_unlock(&subsys->lock); /* @@ -450,6 +550,7 @@ void nvmet_ns_disable(struct nvmet_ns *ns) percpu_ref_exit(&ns->ref); mutex_lock(&subsys->lock); + subsys->nr_namespaces--; nvmet_ns_changed(subsys, ns->nsid); nvmet_ns_dev_disable(ns); @@ -725,6 +826,51 @@ void nvmet_req_execute(struct nvmet_req *req) } EXPORT_SYMBOL_GPL(nvmet_req_execute); +int nvmet_req_alloc_sgl(struct nvmet_req *req) +{ + struct pci_dev *p2p_dev = NULL; + + if (IS_ENABLED(CONFIG_PCI_P2PDMA)) { + if (req->sq->ctrl && req->ns) + p2p_dev = radix_tree_lookup(&req->sq->ctrl->p2p_ns_map, + req->ns->nsid); + + req->p2p_dev = NULL; + if (req->sq->qid && p2p_dev) { + req->sg = pci_p2pmem_alloc_sgl(p2p_dev, &req->sg_cnt, + req->transfer_len); + if (req->sg) { + req->p2p_dev = p2p_dev; + return 0; + } + } + + /* + * If no P2P memory was available we fallback to using + * regular memory + */ + } + + req->sg = sgl_alloc(req->transfer_len, GFP_KERNEL, &req->sg_cnt); + if (!req->sg) + return -ENOMEM; + + return 0; +} +EXPORT_SYMBOL_GPL(nvmet_req_alloc_sgl); + +void nvmet_req_free_sgl(struct nvmet_req *req) +{ + if (req->p2p_dev) + pci_p2pmem_free_sgl(req->p2p_dev, req->sg); + else + sgl_free(req->sg); + + req->sg = NULL; + req->sg_cnt = 0; +} +EXPORT_SYMBOL_GPL(nvmet_req_free_sgl); + static inline bool nvmet_cc_en(u32 cc) { return (cc >> NVME_CC_EN_SHIFT) & 0x1; @@ -921,6 +1067,37 @@ bool nvmet_host_allowed(struct nvmet_req *req, struct nvmet_subsys *subsys, return __nvmet_host_allowed(subsys, hostnqn); } +/* + * Note: ctrl->subsys->lock should be held when calling this function + */ +static void nvmet_setup_p2p_ns_map(struct nvmet_ctrl *ctrl, + struct nvmet_req *req) +{ + struct nvmet_ns *ns; + + if (!req->p2p_client) + return; + + ctrl->p2p_client = get_device(req->p2p_client); + + list_for_each_entry_rcu(ns, &ctrl->subsys->namespaces, dev_link) + nvmet_p2pmem_ns_add_p2p(ctrl, ns); +} + +/* + * Note: ctrl->subsys->lock should be held when calling this function + */ +static void nvmet_release_p2p_ns_map(struct nvmet_ctrl *ctrl) +{ + struct radix_tree_iter iter; + void __rcu **slot; + + radix_tree_for_each_slot(slot, &ctrl->p2p_ns_map, &iter, 0) + pci_dev_put(radix_tree_deref_slot(slot)); + + put_device(ctrl->p2p_client); +} + u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn, struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp) { @@ -962,6 +1139,7 @@ u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn, INIT_WORK(&ctrl->async_event_work, nvmet_async_event_work); INIT_LIST_HEAD(&ctrl->async_events); + INIT_RADIX_TREE(&ctrl->p2p_ns_map, GFP_KERNEL); memcpy(ctrl->subsysnqn, subsysnqn, NVMF_NQN_SIZE); memcpy(ctrl->hostnqn, hostnqn, NVMF_NQN_SIZE); @@ -1026,6 +1204,7 @@ u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn, mutex_lock(&subsys->lock); list_add_tail(&ctrl->subsys_entry, &subsys->ctrls); + nvmet_setup_p2p_ns_map(ctrl, req); mutex_unlock(&subsys->lock); *ctrlp = ctrl; @@ -1053,6 +1232,7 @@ static void nvmet_ctrl_free(struct kref *ref) struct nvmet_subsys *subsys = ctrl->subsys; mutex_lock(&subsys->lock); + nvmet_release_p2p_ns_map(ctrl); list_del(&ctrl->subsys_entry); mutex_unlock(&subsys->lock); |