From 4b8178ec5794f93c71950fdfb1cb5465f6f2e154 Mon Sep 17 00:00:00 2001 From: Dean Balandin Date: Wed, 2 Jun 2021 21:42:42 +0300 Subject: [PATCH] nvme-tcp-offload: Add device scan implementation As part of create_ctrl(), it scans the registered devices and calls the claim_dev op on each of them, to find the first devices that matches the connection params. Once the correct devices is found (claim_dev returns true), we raise the refcnt of that device and return that device as the device to be used for ctrl currently being created. Acked-by: Igor Russkikh Signed-off-by: Dean Balandin Signed-off-by: Prabhakar Kushwaha Signed-off-by: Omkar Kulkarni Signed-off-by: Michal Kalderon Signed-off-by: Ariel Elior Signed-off-by: Shai Malin Reviewed-by: Himanshu Madhani Reviewed-by: Hannes Reinecke Signed-off-by: David S. Miller --- drivers/nvme/host/tcp-offload.c | 77 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 77 insertions(+) diff --git a/drivers/nvme/host/tcp-offload.c b/drivers/nvme/host/tcp-offload.c index f7aa49f..5ee3bbc 100644 --- a/drivers/nvme/host/tcp-offload.c +++ b/drivers/nvme/host/tcp-offload.c @@ -13,6 +13,11 @@ static LIST_HEAD(nvme_tcp_ofld_devices); static DEFINE_MUTEX(nvme_tcp_ofld_devices_mutex); +static inline struct nvme_tcp_ofld_ctrl *to_tcp_ofld_ctrl(struct nvme_ctrl *nctrl) +{ + return container_of(nctrl, struct nvme_tcp_ofld_ctrl, nctrl); +} + /** * nvme_tcp_ofld_register_dev() - NVMeTCP Offload Library registration * function. @@ -96,6 +101,77 @@ void nvme_tcp_ofld_req_done(struct nvme_tcp_ofld_req *req, /* Placeholder - complete request with/without error */ } +static struct nvme_tcp_ofld_dev * +nvme_tcp_ofld_lookup_dev(struct nvme_tcp_ofld_ctrl *ctrl) +{ + struct nvme_tcp_ofld_dev *dev; + + mutex_lock(&nvme_tcp_ofld_devices_mutex); + list_for_each_entry(dev, &nvme_tcp_ofld_devices, entry) { + if (dev->ops->claim_dev(dev, ctrl)) + goto out; + } + + dev = NULL; +out: + mutex_unlock(&nvme_tcp_ofld_devices_mutex); + + return dev; +} + +static struct nvme_ctrl * +nvme_tcp_ofld_create_ctrl(struct device *ndev, struct nvmf_ctrl_options *opts) +{ + struct nvme_tcp_ofld_ctrl *ctrl; + struct nvme_tcp_ofld_dev *dev; + struct nvme_ctrl *nctrl; + int rc = 0; + + ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL); + if (!ctrl) + return ERR_PTR(-ENOMEM); + + nctrl = &ctrl->nctrl; + + /* Init nvme_tcp_ofld_ctrl and nvme_ctrl params based on received opts */ + + /* Find device that can reach the dest addr */ + dev = nvme_tcp_ofld_lookup_dev(ctrl); + if (!dev) { + pr_info("no device found for addr %s:%s.\n", + opts->traddr, opts->trsvcid); + rc = -EINVAL; + goto out_free_ctrl; + } + + /* Increase driver refcnt */ + if (!try_module_get(dev->ops->module)) { + pr_err("try_module_get failed\n"); + dev = NULL; + goto out_free_ctrl; + } + + ctrl->dev = dev; + + if (ctrl->dev->ops->max_hw_sectors) + nctrl->max_hw_sectors = ctrl->dev->ops->max_hw_sectors; + if (ctrl->dev->ops->max_segments) + nctrl->max_segments = ctrl->dev->ops->max_segments; + + /* Init queues */ + + /* Call nvme_init_ctrl */ + + /* Setup ctrl */ + + return nctrl; + +out_free_ctrl: + kfree(ctrl); + + return ERR_PTR(rc); +} + static struct nvmf_transport_ops nvme_tcp_ofld_transport = { .name = "tcp_offload", .module = THIS_MODULE, @@ -105,6 +181,7 @@ static struct nvmf_transport_ops nvme_tcp_ofld_transport = { NVMF_OPT_RECONNECT_DELAY | NVMF_OPT_HDR_DIGEST | NVMF_OPT_DATA_DIGEST | NVMF_OPT_NR_POLL_QUEUES | NVMF_OPT_TOS, + .create_ctrl = nvme_tcp_ofld_create_ctrl, }; static int __init nvme_tcp_ofld_init_module(void) -- 2.7.4