freebsd-src/usr.sbin/nvmfd/controller.c
John Baldwin a8089ea5ae nvmfd: A simple userspace daemon for the NVMe over Fabrics controller
This daemon can operate as a purely userspace controller exporting one
or more simulated RAM disks or local block devices as NVMe namespaces
to a remote host.  In this case the daemon provides a discovery
controller with a single entry for an I/O controller.

nvmfd can also offload I/O controller queue pairs to the nvmft.ko
in-kernel Fabrics controller when -K is passed.  In this mode, nvmfd
still accepts connections and performs initial transport-specific
negotitation in userland.  The daemon still provides a userspace-only
discovery controller with a single entry for an I/O controller.
However, queue pairs for the I/O controller are handed off to the CTL
NVMF frontend.

Eventually ctld(8) should be refactored to to provide an abstraction
for the frontend protocol and the discovery and the kernel mode of
this daemon should be merged into ctld(8).  At that point this daemon
can be moved to tools/tools/nvmf as a debugging tool (mostly as sample
code for a userspace controller using libnvmf).

Reviewed by:	imp
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D44731
2024-05-02 16:38:39 -07:00

245 lines
5.2 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2023-2024 Chelsio Communications, Inc.
* Written by: John Baldwin <jhb@FreeBSD.org>
*/
#include <err.h>
#include <errno.h>
#include <libnvmf.h>
#include <stdlib.h>
#include "internal.h"
struct controller {
struct nvmf_qpair *qp;
uint64_t cap;
uint32_t vs;
uint32_t cc;
uint32_t csts;
bool shutdown;
struct nvme_controller_data cdata;
};
static bool
update_cc(struct controller *c, uint32_t new_cc)
{
uint32_t changes;
if (c->shutdown)
return (false);
if (!nvmf_validate_cc(c->qp, c->cap, c->cc, new_cc))
return (false);
changes = c->cc ^ new_cc;
c->cc = new_cc;
/* Handle shutdown requests. */
if (NVMEV(NVME_CC_REG_SHN, changes) != 0 &&
NVMEV(NVME_CC_REG_SHN, new_cc) != 0) {
c->csts &= ~NVMEM(NVME_CSTS_REG_SHST);
c->csts |= NVMEF(NVME_CSTS_REG_SHST, NVME_SHST_COMPLETE);
c->shutdown = true;
}
if (NVMEV(NVME_CC_REG_EN, changes) != 0) {
if (NVMEV(NVME_CC_REG_EN, new_cc) == 0) {
/* Controller reset. */
c->csts = 0;
c->shutdown = true;
} else
c->csts |= NVMEF(NVME_CSTS_REG_RDY, 1);
}
return (true);
}
static void
handle_property_get(const struct controller *c, const struct nvmf_capsule *nc,
const struct nvmf_fabric_prop_get_cmd *pget)
{
struct nvmf_fabric_prop_get_rsp rsp;
nvmf_init_cqe(&rsp, nc, 0);
switch (le32toh(pget->ofst)) {
case NVMF_PROP_CAP:
if (pget->attrib.size != NVMF_PROP_SIZE_8)
goto error;
rsp.value.u64 = htole64(c->cap);
break;
case NVMF_PROP_VS:
if (pget->attrib.size != NVMF_PROP_SIZE_4)
goto error;
rsp.value.u32.low = htole32(c->vs);
break;
case NVMF_PROP_CC:
if (pget->attrib.size != NVMF_PROP_SIZE_4)
goto error;
rsp.value.u32.low = htole32(c->cc);
break;
case NVMF_PROP_CSTS:
if (pget->attrib.size != NVMF_PROP_SIZE_4)
goto error;
rsp.value.u32.low = htole32(c->csts);
break;
default:
goto error;
}
nvmf_send_response(nc, &rsp);
return;
error:
nvmf_send_generic_error(nc, NVME_SC_INVALID_FIELD);
}
static void
handle_property_set(struct controller *c, const struct nvmf_capsule *nc,
const struct nvmf_fabric_prop_set_cmd *pset)
{
switch (le32toh(pset->ofst)) {
case NVMF_PROP_CC:
if (pset->attrib.size != NVMF_PROP_SIZE_4)
goto error;
if (!update_cc(c, le32toh(pset->value.u32.low)))
goto error;
break;
default:
goto error;
}
nvmf_send_success(nc);
return;
error:
nvmf_send_generic_error(nc, NVME_SC_INVALID_FIELD);
}
static void
handle_fabrics_command(struct controller *c,
const struct nvmf_capsule *nc, const struct nvmf_fabric_cmd *fc)
{
switch (fc->fctype) {
case NVMF_FABRIC_COMMAND_PROPERTY_GET:
handle_property_get(c, nc,
(const struct nvmf_fabric_prop_get_cmd *)fc);
break;
case NVMF_FABRIC_COMMAND_PROPERTY_SET:
handle_property_set(c, nc,
(const struct nvmf_fabric_prop_set_cmd *)fc);
break;
case NVMF_FABRIC_COMMAND_CONNECT:
warnx("CONNECT command on connected queue");
nvmf_send_generic_error(nc, NVME_SC_COMMAND_SEQUENCE_ERROR);
break;
case NVMF_FABRIC_COMMAND_DISCONNECT:
warnx("DISCONNECT command on admin queue");
nvmf_send_error(nc, NVME_SCT_COMMAND_SPECIFIC,
NVMF_FABRIC_SC_INVALID_QUEUE_TYPE);
break;
default:
warnx("Unsupported fabrics command %#x", fc->fctype);
nvmf_send_generic_error(nc, NVME_SC_INVALID_OPCODE);
break;
}
}
static void
handle_identify_command(const struct controller *c,
const struct nvmf_capsule *nc, const struct nvme_command *cmd)
{
uint8_t cns;
cns = le32toh(cmd->cdw10) & 0xFF;
switch (cns) {
case 1:
break;
default:
warnx("Unsupported CNS %#x for IDENTIFY", cns);
goto error;
}
nvmf_send_controller_data(nc, &c->cdata, sizeof(c->cdata));
return;
error:
nvmf_send_generic_error(nc, NVME_SC_INVALID_FIELD);
}
void
controller_handle_admin_commands(struct controller *c, handle_command *cb,
void *cb_arg)
{
struct nvmf_qpair *qp = c->qp;
const struct nvme_command *cmd;
struct nvmf_capsule *nc;
int error;
for (;;) {
error = nvmf_controller_receive_capsule(qp, &nc);
if (error != 0) {
if (error != ECONNRESET)
warnc(error, "Failed to read command capsule");
break;
}
cmd = nvmf_capsule_sqe(nc);
/*
* Only permit Fabrics commands while a controller is
* disabled.
*/
if (NVMEV(NVME_CC_REG_EN, c->cc) == 0 &&
cmd->opc != NVME_OPC_FABRICS_COMMANDS) {
warnx("Unsupported admin opcode %#x whiled disabled\n",
cmd->opc);
nvmf_send_generic_error(nc,
NVME_SC_COMMAND_SEQUENCE_ERROR);
nvmf_free_capsule(nc);
continue;
}
if (cb(nc, cmd, cb_arg)) {
nvmf_free_capsule(nc);
continue;
}
switch (cmd->opc) {
case NVME_OPC_FABRICS_COMMANDS:
handle_fabrics_command(c, nc,
(const struct nvmf_fabric_cmd *)cmd);
break;
case NVME_OPC_IDENTIFY:
handle_identify_command(c, nc, cmd);
break;
default:
warnx("Unsupported admin opcode %#x", cmd->opc);
nvmf_send_generic_error(nc, NVME_SC_INVALID_OPCODE);
break;
}
nvmf_free_capsule(nc);
}
}
struct controller *
init_controller(struct nvmf_qpair *qp,
const struct nvme_controller_data *cdata)
{
struct controller *c;
c = calloc(1, sizeof(*c));
c->qp = qp;
c->cap = nvmf_controller_cap(c->qp);
c->vs = cdata->ver;
c->cdata = *cdata;
return (c);
}
void
free_controller(struct controller *c)
{
free(c);
}