[mirror_ubuntu-artful-kernel.git] / drivers / nvme / target / discovery.c

/*
 * Discovery service for the NVMe over Fabrics target.
 * Copyright (C) 2016 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that 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.
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/slab.h>
#include <generated/utsrelease.h>
#include "nvmet.h"

struct nvmet_subsys *nvmet_disc_subsys;

u64 nvmet_genctr;

void nvmet_referral_enable(struct nvmet_port *parent, struct nvmet_port *port)
{
	down_write(&nvmet_config_sem);
	if (list_empty(&port->entry)) {
		list_add_tail(&port->entry, &parent->referrals);
		port->enabled = true;
		nvmet_genctr++;
	}
	up_write(&nvmet_config_sem);
}

void nvmet_referral_disable(struct nvmet_port *port)
{
	down_write(&nvmet_config_sem);
	if (!list_empty(&port->entry)) {
		port->enabled = false;
		list_del_init(&port->entry);
		nvmet_genctr++;
	}
	up_write(&nvmet_config_sem);
}

static void nvmet_format_discovery_entry(struct nvmf_disc_rsp_page_hdr *hdr,
		struct nvmet_port *port, char *subsys_nqn, u8 type, u32 numrec)
{
	struct nvmf_disc_rsp_page_entry *e = &hdr->entries[numrec];

	e->trtype = port->disc_addr.trtype;
	e->adrfam = port->disc_addr.adrfam;
	e->treq = port->disc_addr.treq;
	e->portid = port->disc_addr.portid;
	/* we support only dynamic controllers */
	e->cntlid = cpu_to_le16(NVME_CNTLID_DYNAMIC);
	e->asqsz = cpu_to_le16(NVME_AQ_DEPTH);
	e->subtype = type;
	memcpy(e->trsvcid, port->disc_addr.trsvcid, NVMF_TRSVCID_SIZE);
	memcpy(e->traddr, port->disc_addr.traddr, NVMF_TRADDR_SIZE);
	memcpy(e->tsas.common, port->disc_addr.tsas.common, NVMF_TSAS_SIZE);
	memcpy(e->subnqn, subsys_nqn, NVMF_NQN_SIZE);
}

static void nvmet_execute_get_disc_log_page(struct nvmet_req *req)
{
	const int entry_size = sizeof(struct nvmf_disc_rsp_page_entry);
	struct nvmet_ctrl *ctrl = req->sq->ctrl;
	struct nvmf_disc_rsp_page_hdr *hdr;
	size_t data_len = nvmet_get_log_page_len(req->cmd);
	size_t alloc_len = max(data_len, sizeof(*hdr));
	int residual_len = data_len - sizeof(*hdr);
	struct nvmet_subsys_link *p;
	struct nvmet_port *r;
	u32 numrec = 0;
	u16 status = 0;

	/*
	 * Make sure we're passing at least a buffer of response header size.
	 * If host provided data len is less than the header size, only the
	 * number of bytes requested by host will be sent to host.
	 */
	hdr = kzalloc(alloc_len, GFP_KERNEL);
	if (!hdr) {
		status = NVME_SC_INTERNAL;
		goto out;
	}

	down_read(&nvmet_config_sem);
	list_for_each_entry(p, &req->port->subsystems, entry) {
		if (!nvmet_host_allowed(req, p->subsys, ctrl->hostnqn))
			continue;
		if (residual_len >= entry_size) {
			nvmet_format_discovery_entry(hdr, req->port,
					p->subsys->subsysnqn,
					NVME_NQN_NVME, numrec);
			residual_len -= entry_size;
		}
		numrec++;
	}

	list_for_each_entry(r, &req->port->referrals, entry) {
		if (residual_len >= entry_size) {
			nvmet_format_discovery_entry(hdr, r,
					NVME_DISC_SUBSYS_NAME,
					NVME_NQN_DISC, numrec);
			residual_len -= entry_size;
		}
		numrec++;
	}

	hdr->genctr = cpu_to_le64(nvmet_genctr);
	hdr->numrec = cpu_to_le64(numrec);
	hdr->recfmt = cpu_to_le16(0);

	up_read(&nvmet_config_sem);

	status = nvmet_copy_to_sgl(req, 0, hdr, data_len);
	kfree(hdr);
out:
	nvmet_req_complete(req, status);
}

static void nvmet_execute_identify_disc_ctrl(struct nvmet_req *req)
{
	struct nvmet_ctrl *ctrl = req->sq->ctrl;
	struct nvme_id_ctrl *id;
	u16 status = 0;

	id = kzalloc(sizeof(*id), GFP_KERNEL);
	if (!id) {
		status = NVME_SC_INTERNAL;
		goto out;
	}

	memset(id->fr, ' ', sizeof(id->fr));
	strncpy((char *)id->fr, UTS_RELEASE, sizeof(id->fr));

	/* no limit on data transfer sizes for now */
	id->mdts = 0;
	id->cntlid = cpu_to_le16(ctrl->cntlid);
	id->ver = cpu_to_le32(ctrl->subsys->ver);
	id->lpa = (1 << 2);

	/* no enforcement soft-limit for maxcmd - pick arbitrary high value */
	id->maxcmd = cpu_to_le16(NVMET_MAX_CMD);

	id->sgls = cpu_to_le32(1 << 0);	/* we always support SGLs */
	if (ctrl->ops->has_keyed_sgls)
		id->sgls |= cpu_to_le32(1 << 2);
	if (ctrl->ops->sqe_inline_size)
		id->sgls |= cpu_to_le32(1 << 20);

	strcpy(id->subnqn, ctrl->subsys->subsysnqn);

	status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id));

	kfree(id);
out:
	nvmet_req_complete(req, status);
}

u16 nvmet_parse_discovery_cmd(struct nvmet_req *req)
{
	struct nvme_command *cmd = req->cmd;

	req->ns = NULL;

	if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
		pr_err("got cmd %d while not ready\n",
		       cmd->common.opcode);
		return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
	}

	switch (cmd->common.opcode) {
	case nvme_admin_get_log_page:
		req->data_len = nvmet_get_log_page_len(cmd);

		switch (cmd->get_log_page.lid) {
		case NVME_LOG_DISC:
			req->execute = nvmet_execute_get_disc_log_page;
			return 0;
		default:
			pr_err("unsupported get_log_page lid %d\n",
			       cmd->get_log_page.lid);
		return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
		}
	case nvme_admin_identify:
		req->data_len = NVME_IDENTIFY_DATA_SIZE;
		switch (cmd->identify.cns) {
		case NVME_ID_CNS_CTRL:
			req->execute =
				nvmet_execute_identify_disc_ctrl;
			return 0;
		default:
			pr_err("unsupported identify cns %d\n",
			       cmd->identify.cns);
			return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
		}
	default:
		pr_err("unsupported cmd %d\n", cmd->common.opcode);
		return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
	}

	pr_err("unhandled cmd %d\n", cmd->common.opcode);
	return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
}

int __init nvmet_init_discovery(void)
{
	nvmet_disc_subsys =
		nvmet_subsys_alloc(NVME_DISC_SUBSYS_NAME, NVME_NQN_DISC);
	if (!nvmet_disc_subsys)
		return -ENOMEM;
	return 0;
}

void nvmet_exit_discovery(void)
{
	nvmet_subsys_put(nvmet_disc_subsys);
}
Commit	Line	Data
a07b4970 CH	1	/*
	2	* Discovery service for the NVMe over Fabrics target.
	3	* Copyright (C) 2016 Intel Corporation. All rights reserved.
	4	*
	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.
	8	*
	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.
	13	*/
	14	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	15	#include <linux/slab.h>
	16	#include <generated/utsrelease.h>
	17	#include "nvmet.h"
	18
	19	struct nvmet_subsys *nvmet_disc_subsys;
	20
	21	u64 nvmet_genctr;
	22
	23	void nvmet_referral_enable(struct nvmet_port parent, struct nvmet_port port)
	24	{
	25	down_write(&nvmet_config_sem);
	26	if (list_empty(&port->entry)) {
	27	list_add_tail(&port->entry, &parent->referrals);
	28	port->enabled = true;
	29	nvmet_genctr++;
	30	}
	31	up_write(&nvmet_config_sem);
	32	}
	33
	34	void nvmet_referral_disable(struct nvmet_port *port)
	35	{
	36	down_write(&nvmet_config_sem);
	37	if (!list_empty(&port->entry)) {
	38	port->enabled = false;
	39	list_del_init(&port->entry);
	40	nvmet_genctr++;
	41	}
	42	up_write(&nvmet_config_sem);
	43	}
	44
	45	static void nvmet_format_discovery_entry(struct nvmf_disc_rsp_page_hdr *hdr,
	46	struct nvmet_port port, char subsys_nqn, u8 type, u32 numrec)
	47	{
	48	struct nvmf_disc_rsp_page_entry *e = &hdr->entries[numrec];
	49
	50	e->trtype = port->disc_addr.trtype;
	51	e->adrfam = port->disc_addr.adrfam;
	52	e->treq = port->disc_addr.treq;
	53	e->portid = port->disc_addr.portid;
	54	/* we support only dynamic controllers */
	55	e->cntlid = cpu_to_le16(NVME_CNTLID_DYNAMIC);
7aa1f427	56	e->asqsz = cpu_to_le16(NVME_AQ_DEPTH);
a446c084	57	e->subtype = type;
a07b4970 CH	58	memcpy(e->trsvcid, port->disc_addr.trsvcid, NVMF_TRSVCID_SIZE);
	59	memcpy(e->traddr, port->disc_addr.traddr, NVMF_TRADDR_SIZE);
	60	memcpy(e->tsas.common, port->disc_addr.tsas.common, NVMF_TSAS_SIZE);
	61	memcpy(e->subnqn, subsys_nqn, NVMF_NQN_SIZE);
	62	}
	63
	64	static void nvmet_execute_get_disc_log_page(struct nvmet_req *req)
	65	{
	66	const int entry_size = sizeof(struct nvmf_disc_rsp_page_entry);
	67	struct nvmet_ctrl *ctrl = req->sq->ctrl;
	68	struct nvmf_disc_rsp_page_hdr *hdr;
	69	size_t data_len = nvmet_get_log_page_len(req->cmd);
	70	size_t alloc_len = max(data_len, sizeof(*hdr));
	71	int residual_len = data_len - sizeof(*hdr);
	72	struct nvmet_subsys_link *p;
	73	struct nvmet_port *r;
	74	u32 numrec = 0;
	75	u16 status = 0;
	76
	77	/*
	78	* Make sure we're passing at least a buffer of response header size.
	79	* If host provided data len is less than the header size, only the
	80	* number of bytes requested by host will be sent to host.
	81	*/
	82	hdr = kzalloc(alloc_len, GFP_KERNEL);
	83	if (!hdr) {
	84	status = NVME_SC_INTERNAL;
	85	goto out;
	86	}
	87
	88	down_read(&nvmet_config_sem);
	89	list_for_each_entry(p, &req->port->subsystems, entry) {
	90	if (!nvmet_host_allowed(req, p->subsys, ctrl->hostnqn))
	91	continue;
	92	if (residual_len >= entry_size) {
	93	nvmet_format_discovery_entry(hdr, req->port,
	94	p->subsys->subsysnqn,
	95	NVME_NQN_NVME, numrec);
	96	residual_len -= entry_size;
	97	}
	98	numrec++;
	99	}
	100
	101	list_for_each_entry(r, &req->port->referrals, entry) {
	102	if (residual_len >= entry_size) {
	103	nvmet_format_discovery_entry(hdr, r,
	104	NVME_DISC_SUBSYS_NAME,
	105	NVME_NQN_DISC, numrec);
	106	residual_len -= entry_size;
	107	}
	108	numrec++;
	109	}
	110
	111	hdr->genctr = cpu_to_le64(nvmet_genctr);
	112	hdr->numrec = cpu_to_le64(numrec);
	113	hdr->recfmt = cpu_to_le16(0);
	114
	115	up_read(&nvmet_config_sem);
	116
	117	status = nvmet_copy_to_sgl(req, 0, hdr, data_len);
	118	kfree(hdr);
	119	out:
	120	nvmet_req_complete(req, status);
	121	}
122
123	static void nvmet_execute_identify_disc_ctrl(struct nvmet_req *req)
124	{
125	struct nvmet_ctrl *ctrl = req->sq->ctrl;
126	struct nvme_id_ctrl *id;
127	u16 status = 0;
128
129	id = kzalloc(sizeof(*id), GFP_KERNEL);
130	if (!id) {
131	status = NVME_SC_INTERNAL;
132	goto out;
133	}
134
135	memset(id->fr, ' ', sizeof(id->fr));
136	strncpy((char *)id->fr, UTS_RELEASE, sizeof(id->fr));
137
138	/* no limit on data transfer sizes for now */
139	id->mdts = 0;
140	id->cntlid = cpu_to_le16(ctrl->cntlid);
141	id->ver = cpu_to_le32(ctrl->subsys->ver);
142	id->lpa = (1 << 2);
143
144	/* no enforcement soft-limit for maxcmd - pick arbitrary high value */
145	id->maxcmd = cpu_to_le16(NVMET_MAX_CMD);
146
147	id->sgls = cpu_to_le32(1 << 0); /* we always support SGLs */
148	if (ctrl->ops->has_keyed_sgls)
149	id->sgls \|= cpu_to_le32(1 << 2);
150	if (ctrl->ops->sqe_inline_size)
151	id->sgls \|= cpu_to_le32(1 << 20);
152
153	strcpy(id->subnqn, ctrl->subsys->subsysnqn);
154
155	status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id));
156
157	kfree(id);
158	out:
159	nvmet_req_complete(req, status);
160	}
161
64a0ca88	162	u16 nvmet_parse_discovery_cmd(struct nvmet_req *req)
a07b4970 CH	163	{
	164	struct nvme_command *cmd = req->cmd;
	165
	166	req->ns = NULL;
	167
	168	if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
4151dd9a PP	169	pr_err("got cmd %d while not ready\n",
4151dd9a PP	170	cmd->common.opcode);
a07b4970 CH	171	return NVME_SC_INVALID_OPCODE \| NVME_SC_DNR;
	172	}
	173
	174	switch (cmd->common.opcode) {
	175	case nvme_admin_get_log_page:
	176	req->data_len = nvmet_get_log_page_len(cmd);
	177
	178	switch (cmd->get_log_page.lid) {
	179	case NVME_LOG_DISC:
	180	req->execute = nvmet_execute_get_disc_log_page;
	181	return 0;
	182	default:
4151dd9a PP	183	pr_err("unsupported get_log_page lid %d\n",
4151dd9a PP	184	cmd->get_log_page.lid);
a07b4970 CH	185	return NVME_SC_INVALID_OPCODE \| NVME_SC_DNR;
	186	}
	187	case nvme_admin_identify:
0add5e8e	188	req->data_len = NVME_IDENTIFY_DATA_SIZE;
986994a2	189	switch (cmd->identify.cns) {
e9c9346e	190	case NVME_ID_CNS_CTRL:
a07b4970 CH	191	req->execute =
	192	nvmet_execute_identify_disc_ctrl;
	193	return 0;
	194	default:
4151dd9a PP	195	pr_err("unsupported identify cns %d\n",
4151dd9a PP	196	cmd->identify.cns);
a07b4970 CH	197	return NVME_SC_INVALID_OPCODE \| NVME_SC_DNR;
	198	}
	199	default:
4151dd9a	200	pr_err("unsupported cmd %d\n", cmd->common.opcode);
a07b4970 CH	201	return NVME_SC_INVALID_OPCODE \| NVME_SC_DNR;
	202	}
	203
4151dd9a	204	pr_err("unhandled cmd %d\n", cmd->common.opcode);
a07b4970 CH	205	return NVME_SC_INVALID_OPCODE \| NVME_SC_DNR;
	206	}
	207
	208	int __init nvmet_init_discovery(void)
	209	{
	210	nvmet_disc_subsys =
	211	nvmet_subsys_alloc(NVME_DISC_SUBSYS_NAME, NVME_NQN_DISC);
	212	if (!nvmet_disc_subsys)
	213	return -ENOMEM;
	214	return 0;
	215	}
	216
	217	void nvmet_exit_discovery(void)
	218	{
	219	nvmet_subsys_put(nvmet_disc_subsys);
	220	}