linux/drivers/nvme/target/discovery.c
Max Gurtovoy 0068a7b010 nvmet: make sure discovery change log event is protected
Generation counter is protected by nvmet_config_sem. Make sure the
callers that call functions that might change it, are calling it
properly.

Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Israel Rukshin <israelr@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-12-01 20:36:37 +01:00

398 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Discovery service for the NVMe over Fabrics target.
* Copyright (C) 2016 Intel Corporation. All rights reserved.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/slab.h>
#include <generated/utsrelease.h>
#include "nvmet.h"
struct nvmet_subsys *nvmet_disc_subsys;
static u64 nvmet_genctr;
static void __nvmet_disc_changed(struct nvmet_port *port,
struct nvmet_ctrl *ctrl)
{
if (ctrl->port != port)
return;
if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_DISC_CHANGE))
return;
nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE,
NVME_AER_NOTICE_DISC_CHANGED, NVME_LOG_DISC);
}
void nvmet_port_disc_changed(struct nvmet_port *port,
struct nvmet_subsys *subsys)
{
struct nvmet_ctrl *ctrl;
lockdep_assert_held(&nvmet_config_sem);
nvmet_genctr++;
mutex_lock(&nvmet_disc_subsys->lock);
list_for_each_entry(ctrl, &nvmet_disc_subsys->ctrls, subsys_entry) {
if (subsys && !nvmet_host_allowed(subsys, ctrl->hostnqn))
continue;
__nvmet_disc_changed(port, ctrl);
}
mutex_unlock(&nvmet_disc_subsys->lock);
/* If transport can signal change, notify transport */
if (port->tr_ops && port->tr_ops->discovery_chg)
port->tr_ops->discovery_chg(port);
}
static void __nvmet_subsys_disc_changed(struct nvmet_port *port,
struct nvmet_subsys *subsys,
struct nvmet_host *host)
{
struct nvmet_ctrl *ctrl;
mutex_lock(&nvmet_disc_subsys->lock);
list_for_each_entry(ctrl, &nvmet_disc_subsys->ctrls, subsys_entry) {
if (host && strcmp(nvmet_host_name(host), ctrl->hostnqn))
continue;
__nvmet_disc_changed(port, ctrl);
}
mutex_unlock(&nvmet_disc_subsys->lock);
}
void nvmet_subsys_disc_changed(struct nvmet_subsys *subsys,
struct nvmet_host *host)
{
struct nvmet_port *port;
struct nvmet_subsys_link *s;
lockdep_assert_held(&nvmet_config_sem);
nvmet_genctr++;
list_for_each_entry(port, nvmet_ports, global_entry)
list_for_each_entry(s, &port->subsystems, entry) {
if (s->subsys != subsys)
continue;
__nvmet_subsys_disc_changed(port, subsys, host);
}
}
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_port_disc_changed(parent, NULL);
}
up_write(&nvmet_config_sem);
}
void nvmet_referral_disable(struct nvmet_port *parent, struct nvmet_port *port)
{
down_write(&nvmet_config_sem);
if (!list_empty(&port->entry)) {
port->enabled = false;
list_del_init(&port->entry);
nvmet_port_disc_changed(parent, NULL);
}
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, char *traddr,
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, traddr, NVMF_TRADDR_SIZE);
memcpy(e->tsas.common, port->disc_addr.tsas.common, NVMF_TSAS_SIZE);
strncpy(e->subnqn, subsys_nqn, NVMF_NQN_SIZE);
}
/*
* nvmet_set_disc_traddr - set a correct discovery log entry traddr
*
* IP based transports (e.g RDMA) can listen on "any" ipv4/ipv6 addresses
* (INADDR_ANY or IN6ADDR_ANY_INIT). The discovery log page traddr reply
* must not contain that "any" IP address. If the transport implements
* .disc_traddr, use it. this callback will set the discovery traddr
* from the req->port address in case the port in question listens
* "any" IP address.
*/
static void nvmet_set_disc_traddr(struct nvmet_req *req, struct nvmet_port *port,
char *traddr)
{
if (req->ops->disc_traddr)
req->ops->disc_traddr(req, port, traddr);
else
memcpy(traddr, port->disc_addr.traddr, NVMF_TRADDR_SIZE);
}
static size_t discovery_log_entries(struct nvmet_req *req)
{
struct nvmet_ctrl *ctrl = req->sq->ctrl;
struct nvmet_subsys_link *p;
struct nvmet_port *r;
size_t entries = 0;
list_for_each_entry(p, &req->port->subsystems, entry) {
if (!nvmet_host_allowed(p->subsys, ctrl->hostnqn))
continue;
entries++;
}
list_for_each_entry(r, &req->port->referrals, entry)
entries++;
return entries;
}
static void nvmet_execute_disc_get_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;
u64 offset = nvmet_get_log_page_offset(req->cmd);
size_t data_len = nvmet_get_log_page_len(req->cmd);
size_t alloc_len;
struct nvmet_subsys_link *p;
struct nvmet_port *r;
u32 numrec = 0;
u16 status = 0;
void *buffer;
if (!nvmet_check_transfer_len(req, data_len))
return;
if (req->cmd->get_log_page.lid != NVME_LOG_DISC) {
req->error_loc =
offsetof(struct nvme_get_log_page_command, lid);
status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
goto out;
}
/* Spec requires dword aligned offsets */
if (offset & 0x3) {
status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
goto out;
}
/*
* 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.
*/
down_read(&nvmet_config_sem);
alloc_len = sizeof(*hdr) + entry_size * discovery_log_entries(req);
buffer = kzalloc(alloc_len, GFP_KERNEL);
if (!buffer) {
up_read(&nvmet_config_sem);
status = NVME_SC_INTERNAL;
goto out;
}
hdr = buffer;
list_for_each_entry(p, &req->port->subsystems, entry) {
char traddr[NVMF_TRADDR_SIZE];
if (!nvmet_host_allowed(p->subsys, ctrl->hostnqn))
continue;
nvmet_set_disc_traddr(req, req->port, traddr);
nvmet_format_discovery_entry(hdr, req->port,
p->subsys->subsysnqn, traddr,
NVME_NQN_NVME, numrec);
numrec++;
}
list_for_each_entry(r, &req->port->referrals, entry) {
nvmet_format_discovery_entry(hdr, r,
NVME_DISC_SUBSYS_NAME,
r->disc_addr.traddr,
NVME_NQN_DISC, numrec);
numrec++;
}
hdr->genctr = cpu_to_le64(nvmet_genctr);
hdr->numrec = cpu_to_le64(numrec);
hdr->recfmt = cpu_to_le16(0);
nvmet_clear_aen_bit(req, NVME_AEN_BIT_DISC_CHANGE);
up_read(&nvmet_config_sem);
status = nvmet_copy_to_sgl(req, 0, buffer + offset, data_len);
kfree(buffer);
out:
nvmet_req_complete(req, status);
}
static void nvmet_execute_disc_identify(struct nvmet_req *req)
{
struct nvmet_ctrl *ctrl = req->sq->ctrl;
struct nvme_id_ctrl *id;
const char model[] = "Linux";
u16 status = 0;
if (!nvmet_check_transfer_len(req, NVME_IDENTIFY_DATA_SIZE))
return;
if (req->cmd->identify.cns != NVME_ID_CNS_CTRL) {
req->error_loc = offsetof(struct nvme_identify, cns);
status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
goto out;
}
id = kzalloc(sizeof(*id), GFP_KERNEL);
if (!id) {
status = NVME_SC_INTERNAL;
goto out;
}
memset(id->sn, ' ', sizeof(id->sn));
bin2hex(id->sn, &ctrl->subsys->serial,
min(sizeof(ctrl->subsys->serial), sizeof(id->sn) / 2));
memset(id->fr, ' ', sizeof(id->fr));
memcpy_and_pad(id->mn, sizeof(id->mn), model, sizeof(model) - 1, ' ');
memcpy_and_pad(id->fr, sizeof(id->fr),
UTS_RELEASE, strlen(UTS_RELEASE), ' ');
/* 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->flags & NVMF_KEYED_SGLS)
id->sgls |= cpu_to_le32(1 << 2);
if (req->port->inline_data_size)
id->sgls |= cpu_to_le32(1 << 20);
id->oaes = cpu_to_le32(NVMET_DISC_AEN_CFG_OPTIONAL);
strlcpy(id->subnqn, ctrl->subsys->subsysnqn, sizeof(id->subnqn));
status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id));
kfree(id);
out:
nvmet_req_complete(req, status);
}
static void nvmet_execute_disc_set_features(struct nvmet_req *req)
{
u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
u16 stat;
if (!nvmet_check_transfer_len(req, 0))
return;
switch (cdw10 & 0xff) {
case NVME_FEAT_KATO:
stat = nvmet_set_feat_kato(req);
break;
case NVME_FEAT_ASYNC_EVENT:
stat = nvmet_set_feat_async_event(req,
NVMET_DISC_AEN_CFG_OPTIONAL);
break;
default:
req->error_loc =
offsetof(struct nvme_common_command, cdw10);
stat = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
break;
}
nvmet_req_complete(req, stat);
}
static void nvmet_execute_disc_get_features(struct nvmet_req *req)
{
u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
u16 stat = 0;
if (!nvmet_check_transfer_len(req, 0))
return;
switch (cdw10 & 0xff) {
case NVME_FEAT_KATO:
nvmet_get_feat_kato(req);
break;
case NVME_FEAT_ASYNC_EVENT:
nvmet_get_feat_async_event(req);
break;
default:
req->error_loc =
offsetof(struct nvme_common_command, cdw10);
stat = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
break;
}
nvmet_req_complete(req, stat);
}
u16 nvmet_parse_discovery_cmd(struct nvmet_req *req)
{
struct nvme_command *cmd = req->cmd;
if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
pr_err("got cmd %d while not ready\n",
cmd->common.opcode);
req->error_loc =
offsetof(struct nvme_common_command, opcode);
return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
}
switch (cmd->common.opcode) {
case nvme_admin_set_features:
req->execute = nvmet_execute_disc_set_features;
return 0;
case nvme_admin_get_features:
req->execute = nvmet_execute_disc_get_features;
return 0;
case nvme_admin_async_event:
req->execute = nvmet_execute_async_event;
return 0;
case nvme_admin_keep_alive:
req->execute = nvmet_execute_keep_alive;
return 0;
case nvme_admin_get_log_page:
req->execute = nvmet_execute_disc_get_log_page;
return 0;
case nvme_admin_identify:
req->execute = nvmet_execute_disc_identify;
return 0;
default:
pr_err("unhandled cmd %d\n", cmd->common.opcode);
req->error_loc = offsetof(struct nvme_common_command, 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);
return PTR_ERR_OR_ZERO(nvmet_disc_subsys);
}
void nvmet_exit_discovery(void)
{
nvmet_subsys_put(nvmet_disc_subsys);
}