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-rw-r--r--drivers/nvme/host/fabrics.h132
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diff --git a/drivers/nvme/host/fabrics.h b/drivers/nvme/host/fabrics.h
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+/*
+ * NVMe over Fabrics common host code.
+ * Copyright (c) 2015-2016 HGST, a Western Digital Company.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+#ifndef _NVME_FABRICS_H
+#define _NVME_FABRICS_H 1
+
+#include <linux/in.h>
+#include <linux/inet.h>
+
+#define NVMF_MIN_QUEUE_SIZE 16
+#define NVMF_MAX_QUEUE_SIZE 1024
+#define NVMF_DEF_QUEUE_SIZE 128
+#define NVMF_DEF_RECONNECT_DELAY 10
+
+/*
+ * Define a host as seen by the target. We allocate one at boot, but also
+ * allow the override it when creating controllers. This is both to provide
+ * persistence of the Host NQN over multiple boots, and to allow using
+ * multiple ones, for example in a container scenario. Because we must not
+ * use different Host NQNs with the same Host ID we generate a Host ID and
+ * use this structure to keep track of the relation between the two.
+ */
+struct nvmf_host {
+ struct kref ref;
+ struct list_head list;
+ char nqn[NVMF_NQN_SIZE];
+ uuid_le id;
+};
+
+/**
+ * enum nvmf_parsing_opts - used to define the sysfs parsing options used.
+ */
+enum {
+ NVMF_OPT_ERR = 0,
+ NVMF_OPT_TRANSPORT = 1 << 0,
+ NVMF_OPT_NQN = 1 << 1,
+ NVMF_OPT_TRADDR = 1 << 2,
+ NVMF_OPT_TRSVCID = 1 << 3,
+ NVMF_OPT_QUEUE_SIZE = 1 << 4,
+ NVMF_OPT_NR_IO_QUEUES = 1 << 5,
+ NVMF_OPT_TL_RETRY_COUNT = 1 << 6,
+ NVMF_OPT_KATO = 1 << 7,
+ NVMF_OPT_HOSTNQN = 1 << 8,
+ NVMF_OPT_RECONNECT_DELAY = 1 << 9,
+};
+
+/**
+ * struct nvmf_ctrl_options - Used to hold the options specified
+ * with the parsing opts enum.
+ * @mask: Used by the fabrics library to parse through sysfs options
+ * on adding a NVMe controller.
+ * @transport: Holds the fabric transport "technology name" (for a lack of
+ * better description) that will be used by an NVMe controller
+ * being added.
+ * @subsysnqn: Hold the fully qualified NQN subystem name (format defined
+ * in the NVMe specification, "NVMe Qualified Names").
+ * @traddr: network address that will be used by the host to communicate
+ * to the added NVMe controller.
+ * @trsvcid: network port used for host-controller communication.
+ * @queue_size: Number of IO queue elements.
+ * @nr_io_queues: Number of controller IO queues that will be established.
+ * @reconnect_delay: Time between two consecutive reconnect attempts.
+ * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN.
+ * @kato: Keep-alive timeout.
+ * @host: Virtual NVMe host, contains the NQN and Host ID.
+ */
+struct nvmf_ctrl_options {
+ unsigned mask;
+ char *transport;
+ char *subsysnqn;
+ char *traddr;
+ char *trsvcid;
+ size_t queue_size;
+ unsigned int nr_io_queues;
+ unsigned int reconnect_delay;
+ bool discovery_nqn;
+ unsigned int kato;
+ struct nvmf_host *host;
+};
+
+/*
+ * struct nvmf_transport_ops - used to register a specific
+ * fabric implementation of NVMe fabrics.
+ * @entry: Used by the fabrics library to add the new
+ * registration entry to its linked-list internal tree.
+ * @name: Name of the NVMe fabric driver implementation.
+ * @required_opts: sysfs command-line options that must be specified
+ * when adding a new NVMe controller.
+ * @allowed_opts: sysfs command-line options that can be specified
+ * when adding a new NVMe controller.
+ * @create_ctrl(): function pointer that points to a non-NVMe
+ * implementation-specific fabric technology
+ * that would go into starting up that fabric
+ * for the purpose of conneciton to an NVMe controller
+ * using that fabric technology.
+ *
+ * Notes:
+ * 1. At minimum, 'required_opts' and 'allowed_opts' should
+ * be set to the same enum parsing options defined earlier.
+ * 2. create_ctrl() must be defined (even if it does nothing)
+ */
+struct nvmf_transport_ops {
+ struct list_head entry;
+ const char *name;
+ int required_opts;
+ int allowed_opts;
+ struct nvme_ctrl *(*create_ctrl)(struct device *dev,
+ struct nvmf_ctrl_options *opts);
+};
+
+int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val);
+int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val);
+int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val);
+int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl);
+int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid);
+void nvmf_register_transport(struct nvmf_transport_ops *ops);
+void nvmf_unregister_transport(struct nvmf_transport_ops *ops);
+void nvmf_free_options(struct nvmf_ctrl_options *opts);
+const char *nvmf_get_subsysnqn(struct nvme_ctrl *ctrl);
+int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size);
+
+#endif /* _NVME_FABRICS_H */