1 // SPDX-License-Identifier: GPL-2.0
3 * Discovery service for the NVMe over Fabrics target.
4 * Copyright (C) 2016 Intel Corporation. All rights reserved.
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7 #include <linux/slab.h>
8 #include <generated/utsrelease.h>
11 struct nvmet_subsys *nvmet_disc_subsys;
13 static u64 nvmet_genctr;
15 static void __nvmet_disc_changed(struct nvmet_port *port,
16 struct nvmet_ctrl *ctrl)
18 if (ctrl->port != port)
21 if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_DISC_CHANGE))
24 nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE,
25 NVME_AER_NOTICE_DISC_CHANGED, NVME_LOG_DISC);
28 void nvmet_port_disc_changed(struct nvmet_port *port,
29 struct nvmet_subsys *subsys)
31 struct nvmet_ctrl *ctrl;
33 lockdep_assert_held(&nvmet_config_sem);
36 mutex_lock(&nvmet_disc_subsys->lock);
37 list_for_each_entry(ctrl, &nvmet_disc_subsys->ctrls, subsys_entry) {
38 if (subsys && !nvmet_host_allowed(subsys, ctrl->hostnqn))
41 __nvmet_disc_changed(port, ctrl);
43 mutex_unlock(&nvmet_disc_subsys->lock);
45 /* If transport can signal change, notify transport */
46 if (port->tr_ops && port->tr_ops->discovery_chg)
47 port->tr_ops->discovery_chg(port);
50 static void __nvmet_subsys_disc_changed(struct nvmet_port *port,
51 struct nvmet_subsys *subsys,
52 struct nvmet_host *host)
54 struct nvmet_ctrl *ctrl;
56 mutex_lock(&nvmet_disc_subsys->lock);
57 list_for_each_entry(ctrl, &nvmet_disc_subsys->ctrls, subsys_entry) {
58 if (host && strcmp(nvmet_host_name(host), ctrl->hostnqn))
61 __nvmet_disc_changed(port, ctrl);
63 mutex_unlock(&nvmet_disc_subsys->lock);
66 void nvmet_subsys_disc_changed(struct nvmet_subsys *subsys,
67 struct nvmet_host *host)
69 struct nvmet_port *port;
70 struct nvmet_subsys_link *s;
74 list_for_each_entry(port, nvmet_ports, global_entry)
75 list_for_each_entry(s, &port->subsystems, entry) {
76 if (s->subsys != subsys)
78 __nvmet_subsys_disc_changed(port, subsys, host);
82 void nvmet_referral_enable(struct nvmet_port *parent, struct nvmet_port *port)
84 down_write(&nvmet_config_sem);
85 if (list_empty(&port->entry)) {
86 list_add_tail(&port->entry, &parent->referrals);
88 nvmet_port_disc_changed(parent, NULL);
90 up_write(&nvmet_config_sem);
93 void nvmet_referral_disable(struct nvmet_port *parent, struct nvmet_port *port)
95 down_write(&nvmet_config_sem);
96 if (!list_empty(&port->entry)) {
97 port->enabled = false;
98 list_del_init(&port->entry);
99 nvmet_port_disc_changed(parent, NULL);
101 up_write(&nvmet_config_sem);
104 static void nvmet_format_discovery_entry(struct nvmf_disc_rsp_page_hdr *hdr,
105 struct nvmet_port *port, char *subsys_nqn, char *traddr,
108 struct nvmf_disc_rsp_page_entry *e = &hdr->entries[numrec];
110 e->trtype = port->disc_addr.trtype;
111 e->adrfam = port->disc_addr.adrfam;
112 e->treq = port->disc_addr.treq;
113 e->portid = port->disc_addr.portid;
114 /* we support only dynamic controllers */
115 e->cntlid = cpu_to_le16(NVME_CNTLID_DYNAMIC);
116 e->asqsz = cpu_to_le16(NVME_AQ_DEPTH);
118 memcpy(e->trsvcid, port->disc_addr.trsvcid, NVMF_TRSVCID_SIZE);
119 memcpy(e->traddr, traddr, NVMF_TRADDR_SIZE);
120 memcpy(e->tsas.common, port->disc_addr.tsas.common, NVMF_TSAS_SIZE);
121 strncpy(e->subnqn, subsys_nqn, NVMF_NQN_SIZE);
125 * nvmet_set_disc_traddr - set a correct discovery log entry traddr
127 * IP based transports (e.g RDMA) can listen on "any" ipv4/ipv6 addresses
128 * (INADDR_ANY or IN6ADDR_ANY_INIT). The discovery log page traddr reply
129 * must not contain that "any" IP address. If the transport implements
130 * .disc_traddr, use it. this callback will set the discovery traddr
131 * from the req->port address in case the port in question listens
134 static void nvmet_set_disc_traddr(struct nvmet_req *req, struct nvmet_port *port,
137 if (req->ops->disc_traddr)
138 req->ops->disc_traddr(req, port, traddr);
140 memcpy(traddr, port->disc_addr.traddr, NVMF_TRADDR_SIZE);
143 static size_t discovery_log_entries(struct nvmet_req *req)
145 struct nvmet_ctrl *ctrl = req->sq->ctrl;
146 struct nvmet_subsys_link *p;
147 struct nvmet_port *r;
150 list_for_each_entry(p, &req->port->subsystems, entry) {
151 if (!nvmet_host_allowed(p->subsys, ctrl->hostnqn))
155 list_for_each_entry(r, &req->port->referrals, entry)
160 static void nvmet_execute_get_disc_log_page(struct nvmet_req *req)
162 const int entry_size = sizeof(struct nvmf_disc_rsp_page_entry);
163 struct nvmet_ctrl *ctrl = req->sq->ctrl;
164 struct nvmf_disc_rsp_page_hdr *hdr;
165 u64 offset = nvmet_get_log_page_offset(req->cmd);
166 size_t data_len = nvmet_get_log_page_len(req->cmd);
168 struct nvmet_subsys_link *p;
169 struct nvmet_port *r;
174 /* Spec requires dword aligned offsets */
176 status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
181 * Make sure we're passing at least a buffer of response header size.
182 * If host provided data len is less than the header size, only the
183 * number of bytes requested by host will be sent to host.
185 down_read(&nvmet_config_sem);
186 alloc_len = sizeof(*hdr) + entry_size * discovery_log_entries(req);
187 buffer = kzalloc(alloc_len, GFP_KERNEL);
189 up_read(&nvmet_config_sem);
190 status = NVME_SC_INTERNAL;
195 list_for_each_entry(p, &req->port->subsystems, entry) {
196 char traddr[NVMF_TRADDR_SIZE];
198 if (!nvmet_host_allowed(p->subsys, ctrl->hostnqn))
201 nvmet_set_disc_traddr(req, req->port, traddr);
202 nvmet_format_discovery_entry(hdr, req->port,
203 p->subsys->subsysnqn, traddr,
204 NVME_NQN_NVME, numrec);
208 list_for_each_entry(r, &req->port->referrals, entry) {
209 nvmet_format_discovery_entry(hdr, r,
210 NVME_DISC_SUBSYS_NAME,
212 NVME_NQN_DISC, numrec);
216 hdr->genctr = cpu_to_le64(nvmet_genctr);
217 hdr->numrec = cpu_to_le64(numrec);
218 hdr->recfmt = cpu_to_le16(0);
220 nvmet_clear_aen_bit(req, NVME_AEN_BIT_DISC_CHANGE);
222 up_read(&nvmet_config_sem);
224 status = nvmet_copy_to_sgl(req, 0, buffer + offset, data_len);
227 nvmet_req_complete(req, status);
230 static void nvmet_execute_identify_disc_ctrl(struct nvmet_req *req)
232 struct nvmet_ctrl *ctrl = req->sq->ctrl;
233 struct nvme_id_ctrl *id;
236 id = kzalloc(sizeof(*id), GFP_KERNEL);
238 status = NVME_SC_INTERNAL;
242 memset(id->fr, ' ', sizeof(id->fr));
243 strncpy((char *)id->fr, UTS_RELEASE, sizeof(id->fr));
245 /* no limit on data transfer sizes for now */
247 id->cntlid = cpu_to_le16(ctrl->cntlid);
248 id->ver = cpu_to_le32(ctrl->subsys->ver);
251 /* no enforcement soft-limit for maxcmd - pick arbitrary high value */
252 id->maxcmd = cpu_to_le16(NVMET_MAX_CMD);
254 id->sgls = cpu_to_le32(1 << 0); /* we always support SGLs */
255 if (ctrl->ops->has_keyed_sgls)
256 id->sgls |= cpu_to_le32(1 << 2);
257 if (req->port->inline_data_size)
258 id->sgls |= cpu_to_le32(1 << 20);
260 id->oaes = cpu_to_le32(NVMET_DISC_AEN_CFG_OPTIONAL);
262 strlcpy(id->subnqn, ctrl->subsys->subsysnqn, sizeof(id->subnqn));
264 status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id));
268 nvmet_req_complete(req, status);
271 static void nvmet_execute_disc_set_features(struct nvmet_req *req)
273 u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
276 switch (cdw10 & 0xff) {
278 stat = nvmet_set_feat_kato(req);
280 case NVME_FEAT_ASYNC_EVENT:
281 stat = nvmet_set_feat_async_event(req,
282 NVMET_DISC_AEN_CFG_OPTIONAL);
286 offsetof(struct nvme_common_command, cdw10);
287 stat = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
291 nvmet_req_complete(req, stat);
294 static void nvmet_execute_disc_get_features(struct nvmet_req *req)
296 u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
299 switch (cdw10 & 0xff) {
301 nvmet_get_feat_kato(req);
303 case NVME_FEAT_ASYNC_EVENT:
304 nvmet_get_feat_async_event(req);
308 offsetof(struct nvme_common_command, cdw10);
309 stat = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
313 nvmet_req_complete(req, stat);
316 u16 nvmet_parse_discovery_cmd(struct nvmet_req *req)
318 struct nvme_command *cmd = req->cmd;
320 if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
321 pr_err("got cmd %d while not ready\n",
324 offsetof(struct nvme_common_command, opcode);
325 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
328 switch (cmd->common.opcode) {
329 case nvme_admin_set_features:
330 req->execute = nvmet_execute_disc_set_features;
333 case nvme_admin_get_features:
334 req->execute = nvmet_execute_disc_get_features;
337 case nvme_admin_async_event:
338 req->execute = nvmet_execute_async_event;
341 case nvme_admin_keep_alive:
342 req->execute = nvmet_execute_keep_alive;
345 case nvme_admin_get_log_page:
346 req->data_len = nvmet_get_log_page_len(cmd);
348 switch (cmd->get_log_page.lid) {
350 req->execute = nvmet_execute_get_disc_log_page;
353 pr_err("unsupported get_log_page lid %d\n",
354 cmd->get_log_page.lid);
356 offsetof(struct nvme_get_log_page_command, lid);
357 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
359 case nvme_admin_identify:
360 req->data_len = NVME_IDENTIFY_DATA_SIZE;
361 switch (cmd->identify.cns) {
362 case NVME_ID_CNS_CTRL:
364 nvmet_execute_identify_disc_ctrl;
367 pr_err("unsupported identify cns %d\n",
369 req->error_loc = offsetof(struct nvme_identify, cns);
370 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
373 pr_err("unhandled cmd %d\n", cmd->common.opcode);
374 req->error_loc = offsetof(struct nvme_common_command, opcode);
375 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
380 int __init nvmet_init_discovery(void)
383 nvmet_subsys_alloc(NVME_DISC_SUBSYS_NAME, NVME_NQN_DISC);
384 if (IS_ERR(nvmet_disc_subsys))
385 return PTR_ERR(nvmet_disc_subsys);
389 void nvmet_exit_discovery(void)
391 nvmet_subsys_put(nvmet_disc_subsys);