2 * Discovery service for the NVMe over Fabrics target.
3 * Copyright (C) 2016 Intel Corporation. All rights reserved.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License version
7 * 2 as published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15 #include <linux/slab.h>
16 #include <generated/utsrelease.h>
19 struct nvmet_subsys *nvmet_disc_subsys;
23 void nvmet_referral_enable(struct nvmet_port *parent, struct nvmet_port *port)
25 down_write(&nvmet_config_sem);
26 if (list_empty(&port->entry)) {
27 list_add_tail(&port->entry, &parent->referrals);
31 up_write(&nvmet_config_sem);
34 void nvmet_referral_disable(struct nvmet_port *port)
36 down_write(&nvmet_config_sem);
37 if (!list_empty(&port->entry)) {
38 port->enabled = false;
39 list_del_init(&port->entry);
42 up_write(&nvmet_config_sem);
45 static void nvmet_format_discovery_entry(struct nvmf_disc_rsp_page_hdr *hdr,
46 struct nvmet_port *port, char *subsys_nqn, char *traddr,
49 struct nvmf_disc_rsp_page_entry *e = &hdr->entries[numrec];
51 e->trtype = port->disc_addr.trtype;
52 e->adrfam = port->disc_addr.adrfam;
53 e->treq = port->disc_addr.treq;
54 e->portid = port->disc_addr.portid;
55 /* we support only dynamic controllers */
56 e->cntlid = cpu_to_le16(NVME_CNTLID_DYNAMIC);
57 e->asqsz = cpu_to_le16(NVME_AQ_DEPTH);
59 memcpy(e->trsvcid, port->disc_addr.trsvcid, NVMF_TRSVCID_SIZE);
60 memcpy(e->traddr, traddr, NVMF_TRADDR_SIZE);
61 memcpy(e->tsas.common, port->disc_addr.tsas.common, NVMF_TSAS_SIZE);
62 strncpy(e->subnqn, subsys_nqn, NVMF_NQN_SIZE);
66 * nvmet_set_disc_traddr - set a correct discovery log entry traddr
68 * IP based transports (e.g RDMA) can listen on "any" ipv4/ipv6 addresses
69 * (INADDR_ANY or IN6ADDR_ANY_INIT). The discovery log page traddr reply
70 * must not contain that "any" IP address. If the transport implements
71 * .disc_traddr, use it. this callback will set the discovery traddr
72 * from the req->port address in case the port in question listens
75 static void nvmet_set_disc_traddr(struct nvmet_req *req, struct nvmet_port *port,
78 if (req->ops->disc_traddr)
79 req->ops->disc_traddr(req, port, traddr);
81 memcpy(traddr, port->disc_addr.traddr, NVMF_TRADDR_SIZE);
84 static void nvmet_execute_get_disc_log_page(struct nvmet_req *req)
86 const int entry_size = sizeof(struct nvmf_disc_rsp_page_entry);
87 struct nvmet_ctrl *ctrl = req->sq->ctrl;
88 struct nvmf_disc_rsp_page_hdr *hdr;
89 size_t data_len = nvmet_get_log_page_len(req->cmd);
90 size_t alloc_len = max(data_len, sizeof(*hdr));
91 int residual_len = data_len - sizeof(*hdr);
92 struct nvmet_subsys_link *p;
98 * Make sure we're passing at least a buffer of response header size.
99 * If host provided data len is less than the header size, only the
100 * number of bytes requested by host will be sent to host.
102 hdr = kzalloc(alloc_len, GFP_KERNEL);
104 status = NVME_SC_INTERNAL;
108 down_read(&nvmet_config_sem);
109 list_for_each_entry(p, &req->port->subsystems, entry) {
110 if (!nvmet_host_allowed(p->subsys, ctrl->hostnqn))
112 if (residual_len >= entry_size) {
113 char traddr[NVMF_TRADDR_SIZE];
115 nvmet_set_disc_traddr(req, req->port, traddr);
116 nvmet_format_discovery_entry(hdr, req->port,
117 p->subsys->subsysnqn, traddr,
118 NVME_NQN_NVME, numrec);
119 residual_len -= entry_size;
124 list_for_each_entry(r, &req->port->referrals, entry) {
125 if (residual_len >= entry_size) {
126 nvmet_format_discovery_entry(hdr, r,
127 NVME_DISC_SUBSYS_NAME,
129 NVME_NQN_DISC, numrec);
130 residual_len -= entry_size;
135 hdr->genctr = cpu_to_le64(nvmet_genctr);
136 hdr->numrec = cpu_to_le64(numrec);
137 hdr->recfmt = cpu_to_le16(0);
139 up_read(&nvmet_config_sem);
141 status = nvmet_copy_to_sgl(req, 0, hdr, data_len);
144 nvmet_req_complete(req, status);
147 static void nvmet_execute_identify_disc_ctrl(struct nvmet_req *req)
149 struct nvmet_ctrl *ctrl = req->sq->ctrl;
150 struct nvme_id_ctrl *id;
153 id = kzalloc(sizeof(*id), GFP_KERNEL);
155 status = NVME_SC_INTERNAL;
159 memset(id->fr, ' ', sizeof(id->fr));
160 strncpy((char *)id->fr, UTS_RELEASE, sizeof(id->fr));
162 /* no limit on data transfer sizes for now */
164 id->cntlid = cpu_to_le16(ctrl->cntlid);
165 id->ver = cpu_to_le32(ctrl->subsys->ver);
168 /* no enforcement soft-limit for maxcmd - pick arbitrary high value */
169 id->maxcmd = cpu_to_le16(NVMET_MAX_CMD);
171 id->sgls = cpu_to_le32(1 << 0); /* we always support SGLs */
172 if (ctrl->ops->has_keyed_sgls)
173 id->sgls |= cpu_to_le32(1 << 2);
174 if (req->port->inline_data_size)
175 id->sgls |= cpu_to_le32(1 << 20);
177 strlcpy(id->subnqn, ctrl->subsys->subsysnqn, sizeof(id->subnqn));
179 status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id));
183 nvmet_req_complete(req, status);
186 static void nvmet_execute_disc_set_features(struct nvmet_req *req)
188 u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10[0]);
191 switch (cdw10 & 0xff) {
193 stat = nvmet_set_feat_kato(req);
195 case NVME_FEAT_ASYNC_EVENT:
196 stat = nvmet_set_feat_async_event(req,
197 NVMET_DISC_AEN_CFG_OPTIONAL);
200 stat = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
204 nvmet_req_complete(req, stat);
207 static void nvmet_execute_disc_get_features(struct nvmet_req *req)
209 u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10[0]);
212 switch (cdw10 & 0xff) {
214 nvmet_get_feat_kato(req);
216 case NVME_FEAT_ASYNC_EVENT:
217 nvmet_get_feat_async_event(req);
220 stat = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
224 nvmet_req_complete(req, stat);
227 u16 nvmet_parse_discovery_cmd(struct nvmet_req *req)
229 struct nvme_command *cmd = req->cmd;
231 if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
232 pr_err("got cmd %d while not ready\n",
234 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
237 switch (cmd->common.opcode) {
238 case nvme_admin_set_features:
239 req->execute = nvmet_execute_disc_set_features;
242 case nvme_admin_get_features:
243 req->execute = nvmet_execute_disc_get_features;
246 case nvme_admin_async_event:
247 req->execute = nvmet_execute_async_event;
250 case nvme_admin_keep_alive:
251 req->execute = nvmet_execute_keep_alive;
254 case nvme_admin_get_log_page:
255 req->data_len = nvmet_get_log_page_len(cmd);
257 switch (cmd->get_log_page.lid) {
259 req->execute = nvmet_execute_get_disc_log_page;
262 pr_err("unsupported get_log_page lid %d\n",
263 cmd->get_log_page.lid);
264 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
266 case nvme_admin_identify:
267 req->data_len = NVME_IDENTIFY_DATA_SIZE;
268 switch (cmd->identify.cns) {
269 case NVME_ID_CNS_CTRL:
271 nvmet_execute_identify_disc_ctrl;
274 pr_err("unsupported identify cns %d\n",
276 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
279 pr_err("unhandled cmd %d\n", cmd->common.opcode);
280 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
285 int __init nvmet_init_discovery(void)
288 nvmet_subsys_alloc(NVME_DISC_SUBSYS_NAME, NVME_NQN_DISC);
289 if (!nvmet_disc_subsys)
294 void nvmet_exit_discovery(void)
296 nvmet_subsys_put(nvmet_disc_subsys);