[RFC PATCH v4 10/27] nvme-tcp-offload: Add device scan implementation
From: Shai Malin <hidden>
Date: 2021-04-29 19:16:18
Also in:
linux-nvme
Subsystem:
nvm express driver, the rest · Maintainers:
Keith Busch, Jens Axboe, Christoph Hellwig, Sagi Grimberg, Linus Torvalds
From: Dean Balandin <redacted> 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 <redacted> Signed-off-by: Dean Balandin <redacted> Signed-off-by: Prabhakar Kushwaha <redacted> Signed-off-by: Omkar Kulkarni <redacted> Signed-off-by: Michal Kalderon <mkalderon@marvell.com> Signed-off-by: Ariel Elior <redacted> Signed-off-by: Shai Malin <redacted> --- drivers/nvme/host/tcp-offload.c | 94 +++++++++++++++++++++++++++++++++ 1 file changed, 94 insertions(+)
diff --git a/drivers/nvme/host/tcp-offload.c b/drivers/nvme/host/tcp-offload.c
index 711232eba339..aa7cc239abf2 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 DECLARE_RWSEM(nvme_tcp_ofld_devices_rwsem); +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.
@@ -98,6 +103,94 @@ void nvme_tcp_ofld_req_done(struct nvme_tcp_ofld_req *req, /* Placeholder - complete request with/without error */ } +struct nvme_tcp_ofld_dev * +nvme_tcp_ofld_lookup_dev(struct nvme_tcp_ofld_ctrl *ctrl) +{ + struct nvme_tcp_ofld_dev *dev; + + down_read(&nvme_tcp_ofld_devices_rwsem); + list_for_each_entry(dev, &nvme_tcp_ofld_devices, entry) { + if (dev->ops->claim_dev(dev, &ctrl->conn_params)) { + /* Increase driver refcnt */ + if (!try_module_get(dev->ops->module)) { + pr_err("try_module_get failed\n"); + dev = NULL; + } + + goto out; + } + } + + dev = NULL; +out: + up_read(&nvme_tcp_ofld_devices_rwsem); + + return dev; +} + +static int nvme_tcp_ofld_setup_ctrl(struct nvme_ctrl *nctrl, bool new) +{ + /* Placeholder - validates inputs and creates admin and IO queues */ + + return 0; +} + +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; + } + + 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 */ + + rc = ctrl->dev->ops->setup_ctrl(ctrl, true); + if (rc) + goto out_module_put; + + rc = nvme_tcp_ofld_setup_ctrl(nctrl, true); + if (rc) + goto out_uninit_ctrl; + + return nctrl; + +out_uninit_ctrl: + ctrl->dev->ops->release_ctrl(ctrl); +out_module_put: + module_put(dev->ops->module); +out_free_ctrl: + kfree(ctrl); + + return ERR_PTR(rc); +} + static struct nvmf_transport_ops nvme_tcp_ofld_transport = { .name = "tcp_offload", .module = THIS_MODULE,
@@ -107,6 +200,7 @@ 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)
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2.22.0