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-rw-r--r--drivers/nvme/host/fabrics.h230
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diff --git a/drivers/nvme/host/fabrics.h b/drivers/nvme/host/fabrics.h
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+++ b/drivers/nvme/host/fabrics.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * NVMe over Fabrics common host code.
+ * Copyright (c) 2015-2016 HGST, a Western Digital Company.
+ */
+#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
+/* default to 600 seconds of reconnect attempts before giving up */
+#define NVMF_DEF_CTRL_LOSS_TMO 600
+/* default is -1: the fail fast mechanism is disabled */
+#define NVMF_DEF_FAIL_FAST_TMO -1
+
+/*
+ * Reserved one command for internal usage. This command is used for sending
+ * the connect command, as well as for the keep alive command on the admin
+ * queue once live.
+ */
+#define NVMF_RESERVED_TAGS 1
+
+/*
+ * 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_t 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,
+ NVMF_OPT_HOST_TRADDR = 1 << 10,
+ NVMF_OPT_CTRL_LOSS_TMO = 1 << 11,
+ NVMF_OPT_HOST_ID = 1 << 12,
+ NVMF_OPT_DUP_CONNECT = 1 << 13,
+ NVMF_OPT_DISABLE_SQFLOW = 1 << 14,
+ NVMF_OPT_HDR_DIGEST = 1 << 15,
+ NVMF_OPT_DATA_DIGEST = 1 << 16,
+ NVMF_OPT_NR_WRITE_QUEUES = 1 << 17,
+ NVMF_OPT_NR_POLL_QUEUES = 1 << 18,
+ NVMF_OPT_TOS = 1 << 19,
+ NVMF_OPT_FAIL_FAST_TMO = 1 << 20,
+ NVMF_OPT_HOST_IFACE = 1 << 21,
+ NVMF_OPT_DISCOVERY = 1 << 22,
+ NVMF_OPT_DHCHAP_SECRET = 1 << 23,
+ NVMF_OPT_DHCHAP_CTRL_SECRET = 1 << 24,
+};
+
+/**
+ * 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.
+ * @max_reconnects: maximum number of allowed reconnect attempts before removing
+ * the controller, (-1) means reconnect forever, zero means remove
+ * immediately;
+ * @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: The transport-specific TRADDR field for a port on the
+ * subsystem which is adding a controller.
+ * @trsvcid: The transport-specific TRSVCID field for a port on the
+ * subsystem which is adding a controller.
+ * @host_traddr: A transport-specific field identifying the NVME host port
+ * to use for the connection to the controller.
+ * @host_iface: A transport-specific field identifying the NVME host
+ * interface to use for the connection to the controller.
+ * @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.
+ * @dhchap_secret: DH-HMAC-CHAP secret
+ * @dhchap_ctrl_secret: DH-HMAC-CHAP controller secret for bi-directional
+ * authentication
+ * @disable_sqflow: disable controller sq flow control
+ * @hdr_digest: generate/verify header digest (TCP)
+ * @data_digest: generate/verify data digest (TCP)
+ * @nr_write_queues: number of queues for write I/O
+ * @nr_poll_queues: number of queues for polling I/O
+ * @tos: type of service
+ * @fast_io_fail_tmo: Fast I/O fail timeout in seconds
+ */
+struct nvmf_ctrl_options {
+ unsigned mask;
+ int max_reconnects;
+ char *transport;
+ char *subsysnqn;
+ char *traddr;
+ char *trsvcid;
+ char *host_traddr;
+ char *host_iface;
+ size_t queue_size;
+ unsigned int nr_io_queues;
+ unsigned int reconnect_delay;
+ bool discovery_nqn;
+ bool duplicate_connect;
+ unsigned int kato;
+ struct nvmf_host *host;
+ char *dhchap_secret;
+ char *dhchap_ctrl_secret;
+ bool disable_sqflow;
+ bool hdr_digest;
+ bool data_digest;
+ unsigned int nr_write_queues;
+ unsigned int nr_poll_queues;
+ int tos;
+ int fast_io_fail_tmo;
+};
+
+/*
+ * 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.
+ * @module: Transport module reference
+ * @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)
+ * 3. struct nvmf_transport_ops must be statically allocated in the
+ * modules .bss section so that a pure module_get on @module
+ * prevents the memory from beeing freed.
+ */
+struct nvmf_transport_ops {
+ struct list_head entry;
+ struct module *module;
+ const char *name;
+ int required_opts;
+ int allowed_opts;
+ struct nvme_ctrl *(*create_ctrl)(struct device *dev,
+ struct nvmf_ctrl_options *opts);
+};
+
+static inline bool
+nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl,
+ struct nvmf_ctrl_options *opts)
+{
+ if (ctrl->state == NVME_CTRL_DELETING ||
+ ctrl->state == NVME_CTRL_DELETING_NOIO ||
+ ctrl->state == NVME_CTRL_DEAD ||
+ strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) ||
+ strcmp(opts->host->nqn, ctrl->opts->host->nqn) ||
+ !uuid_equal(&opts->host->id, &ctrl->opts->host->id))
+ return false;
+
+ return true;
+}
+
+static inline char *nvmf_ctrl_subsysnqn(struct nvme_ctrl *ctrl)
+{
+ if (!ctrl->subsys ||
+ !strcmp(ctrl->opts->subsysnqn, NVME_DISC_SUBSYS_NAME))
+ return ctrl->opts->subsysnqn;
+ return ctrl->subsys->subnqn;
+}
+
+static inline void nvmf_complete_timed_out_request(struct request *rq)
+{
+ if (blk_mq_request_started(rq) && !blk_mq_request_completed(rq)) {
+ nvme_req(rq)->status = NVME_SC_HOST_ABORTED_CMD;
+ blk_mq_complete_request(rq);
+ }
+}
+
+static inline unsigned int nvmf_nr_io_queues(struct nvmf_ctrl_options *opts)
+{
+ return min(opts->nr_io_queues, num_online_cpus()) +
+ min(opts->nr_write_queues, num_online_cpus()) +
+ min(opts->nr_poll_queues, num_online_cpus());
+}
+
+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);
+int 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);
+int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size);
+bool nvmf_should_reconnect(struct nvme_ctrl *ctrl);
+bool nvmf_ip_options_match(struct nvme_ctrl *ctrl,
+ struct nvmf_ctrl_options *opts);
+void nvmf_set_io_queues(struct nvmf_ctrl_options *opts, u32 nr_io_queues,
+ u32 io_queues[HCTX_MAX_TYPES]);
+void nvmf_map_queues(struct blk_mq_tag_set *set, struct nvme_ctrl *ctrl,
+ u32 io_queues[HCTX_MAX_TYPES]);
+
+#endif /* _NVME_FABRICS_H */