// SPDX-License-Identifier: GPL-2.0
/*
* Serial Attached SCSI (SAS) Discover process
*
* Copyright (C) 2005 Adaptec, Inc. All rights reserved.
* Copyright (C) 2005 Luben Tuikov <[email protected]>
*/
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_eh.h>
#include "sas_internal.h"
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_sas.h>
#include <scsi/sas_ata.h>
#include "scsi_sas_internal.h"
/* ---------- Basic task processing for discovery purposes ---------- */
void sas_init_dev(struct domain_device *dev)
{
switch (dev->dev_type) {
case SAS_END_DEVICE:
INIT_LIST_HEAD(&dev->ssp_dev.eh_list_node);
break;
case SAS_EDGE_EXPANDER_DEVICE:
case SAS_FANOUT_EXPANDER_DEVICE:
INIT_LIST_HEAD(&dev->ex_dev.children);
mutex_init(&dev->ex_dev.cmd_mutex);
break;
default:
break;
}
}
/* ---------- Domain device discovery ---------- */
/**
* sas_get_port_device - Discover devices which caused port creation
* @port: pointer to struct sas_port of interest
*
* Devices directly attached to a HA port, have no parent. This is
* how we know they are (domain) "root" devices. All other devices
* do, and should have their "parent" pointer set appropriately as
* soon as a child device is discovered.
*/
static int sas_get_port_device(struct asd_sas_port *port)
{
struct asd_sas_phy *phy;
struct sas_rphy *rphy;
struct domain_device *dev;
int rc = -ENODEV;
dev = sas_alloc_device();
if (!dev)
return -ENOMEM;
spin_lock_irq(&port->phy_list_lock);
if (list_empty(&port->phy_list)) {
spin_unlock_irq(&port->phy_list_lock);
sas_put_device(dev);
return -ENODEV;
}
phy = container_of(port->phy_list.next, struct asd_sas_phy, port_phy_el);
spin_lock(&phy->frame_rcvd_lock);
memcpy(dev->frame_rcvd, phy->frame_rcvd, min(sizeof(dev->frame_rcvd),
(size_t)phy->frame_rcvd_size));
spin_unlock(&phy->frame_rcvd_lock);
spin_unlock_irq(&port->phy_list_lock);
if (dev->frame_rcvd[0] == 0x34 && port->oob_mode == SATA_OOB_MODE) {
struct dev_to_host_fis *fis =
(struct dev_to_host_fis *) dev->frame_rcvd;
if (fis->interrupt_reason == 1 && fis->lbal == 1 &&
fis->byte_count_low == 0x69 && fis->byte_count_high == 0x96
&& (fis->device & ~0x10) == 0)
dev->dev_type = SAS_SATA_PM;
else
dev->dev_type = SAS_SATA_DEV;
dev->tproto = SAS_PROTOCOL_SATA;
} else if (port->oob_mode == SAS_OOB_MODE) {
struct sas_identify_frame *id =
(struct sas_identify_frame *) dev->frame_rcvd;
dev->dev_type = id->dev_type;
dev->iproto = id->initiator_bits;
dev->tproto = id->target_bits;
} else {
/* If the oob mode is OOB_NOT_CONNECTED, the port is
* disconnected due to race with PHY down. We cannot
* continue to discover this port
*/
sas_put_device(dev);
pr_warn("Port %016llx is disconnected when discovering\n",
SAS_ADDR(port->attached_sas_addr));
return -ENODEV;
}
sas_init_dev(dev);
dev->port = port;
switch (dev->dev_type) {
case SAS_SATA_DEV:
rc = sas_ata_init(dev);
if (rc) {
rphy = NULL;
break;
}
fallthrough;
case SAS_END_DEVICE:
rphy = sas_end_device_alloc(port->port);
break;
case SAS_EDGE_EXPANDER_DEVICE:
rphy = sas_expander_alloc(port->port,
SAS_EDGE_EXPANDER_DEVICE);
break;
case SAS_FANOUT_EXPANDER_DEVICE:
rphy = sas_expander_alloc(port->port,
SAS_FANOUT_EXPANDER_DEVICE);
break;
default:
pr_warn("ERROR: Unidentified device type %d\n", dev->dev_type);
rphy = NULL;
break;
}
if (!rphy) {
sas_put_device(dev);
return rc;
}
rphy->identify.phy_identifier = phy->phy->identify.phy_identifier;
memcpy(dev->sas_addr, port->attached_sas_addr, SAS_ADDR_SIZE);
sas_fill_in_rphy(dev, rphy);
sas_hash_addr(dev->hashed_sas_addr, dev->sas_addr);
port->port_dev = dev;
dev->linkrate = port->linkrate;
dev->min_linkrate = port->linkrate;
dev->max_linkrate = port->linkrate;
dev->pathways = port->num_phys;
memset(port->disc.fanout_sas_addr, 0, SAS_ADDR_SIZE);
memset(port->disc.eeds_a, 0, SAS_ADDR_SIZE);
memset(port->disc.eeds_b, 0, SAS_ADDR_SIZE);
port->disc.max_level = 0;
sas_device_set_phy(dev, port->port);
dev->rphy = rphy;
get_device(&dev->rphy->dev);
if (dev_is_sata(dev) || dev->dev_type == SAS_END_DEVICE)
list_add_tail(&dev->disco_list_node, &port->disco_list);
else {
spin_lock_irq(&port->dev_list_lock);
list_add_tail(&dev->dev_list_node, &port->dev_list);
spin_unlock_irq(&port->dev_list_lock);
}
spin_lock_irq(&port->phy_list_lock);
list_for_each_entry(phy, &port->phy_list, port_phy_el)
sas_phy_set_target(phy, dev);
spin_unlock_irq(&port->phy_list_lock);
return 0;
}
/* ---------- Discover and Revalidate ---------- */
int sas_notify_lldd_dev_found(struct domain_device *dev)
{
int res = 0;
struct sas_ha_struct *sas_ha = dev->port->ha;
struct Scsi_Host *shost = sas_ha->shost;
struct sas_internal *i = to_sas_internal(shost->transportt);
if (!i->dft->lldd_dev_found)
return 0;
res = i->dft->lldd_dev_found(dev);
if (res) {
pr_warn("driver on host %s cannot handle device %016llx, error:%d\n",
dev_name(sas_ha->dev),
SAS_ADDR(dev->sas_addr), res);
return res;
}
set_bit(SAS_DEV_FOUND, &dev->state);
kref_get(&dev->kref);
return 0;
}
void sas_notify_lldd_dev_gone(struct domain_device *dev)
{
struct sas_ha_struct *sas_ha = dev->port->ha;
struct Scsi_Host *shost = sas_ha->shost;
struct sas_internal *i = to_sas_internal(shost->transportt);
if (!i->dft->lldd_dev_gone)
return;
if (test_and_clear_bit(SAS_DEV_FOUND, &dev->state)) {
i->dft->lldd_dev_gone(dev);
sas_put_device(dev);
}
}
static void sas_probe_devices(struct asd_sas_port *port)
{
struct domain_device *dev, *n;
/* devices must be domain members before link recovery and probe */
list_for_each_entry(dev, &port->disco_list, disco_list_node) {
spin_lock_irq(&port->dev_list_lock);
list_add_tail(&dev->dev_list_node, &port->dev_list);
spin_unlock_irq(&port->dev_list_lock);
}
sas_probe_sata(port);
list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) {
int err;
err = sas_rphy_add(dev->rphy);
if (err)
sas_fail_probe(dev, __func__, err);
else
list_del_init(&dev->disco_list_node);
}
}
static void sas_suspend_devices(struct work_struct *work)
{
struct asd_sas_phy *phy;
struct domain_device *dev;
struct sas_discovery_event *ev = to_sas_discovery_event(work);
struct asd_sas_port *port = ev->port;
struct Scsi_Host *shost = port->ha->shost;
struct sas_internal *si = to_sas_internal(shost->transportt);
clear_bit(DISCE_SUSPEND, &port->disc.pending);
sas_suspend_sata(port);
/* lldd is free to forget the domain_device across the
* suspension, we force the issue here to keep the reference
* counts aligned
*/
list_for_each_entry(dev, &port->dev_list, dev_list_node)
sas_notify_lldd_dev_gone(dev);
/* we are suspending, so we know events are disabled and
* phy_list is not being mutated
*/
list_for_each_entry(phy, &port->phy_list, port_phy_el) {
if (si->dft->lldd_port_deformed)
si->dft->lldd_port_deformed(phy);
phy->suspended = 1;
port->suspended = 1;
}
}
static void sas_resume_devices(struct work_struct *work)
{
struct sas_discovery_event *ev = to_sas_discovery_event(work);
struct asd_sas_port *port = ev->port;
clear_bit(DISCE_RESUME, &port->disc.pending);
sas_resume_sata(port);
}
/**
* sas_discover_end_dev - discover an end device (SSP, etc)
* @dev: pointer to domain device of interest
*
* See comment in sas_discover_sata().
*/
static int sas_discover_end_dev(struct domain_device *dev)
{
return sas_notify_lldd_dev_found(dev);
}
/* ---------- Device registration and unregistration ---------- */
void sas_free_device(struct kref *kref)
{
struct domain_device *dev = container_of(kref, typeof(*dev), kref);
put_device(&dev->rphy->dev);
dev->rphy = NULL;
if (dev->parent)
sas_put_device(dev->parent);
sas_port_put_phy(dev->phy);
dev->phy = NULL;
/* remove the phys and ports, everything else should be gone */
if (dev_is_expander(dev->dev_type))
kfree(dev->ex_dev.ex_phy);
if (dev_is_sata(dev) && dev->sata_dev.ap) {
ata_tport_delete(dev->sata_dev.ap);
ata_port_free(dev->sata_dev.ap);
ata_host_put(dev->sata_dev.ata_host);
dev->sata_dev.ata_host = NULL;
dev->sata_dev.ap = NULL;
}
kfree(dev);
}
static void sas_unregister_common_dev(struct asd_sas_port *port, struct domain_device *dev)
{
struct sas_ha_struct *ha = port->ha;
sas_notify_lldd_dev_gone(dev);
if (!dev->parent)
dev->port->port_dev = NULL;
else
list_del_init(&dev->siblings);
spin_lock_irq(&port->dev_list_lock);
list_del_init(&dev->dev_list_node);
if (dev_is_sata(dev))
sas_ata_end_eh(dev->sata_dev.ap);
spin_unlock_irq(&port->dev_list_lock);
spin_lock_irq(&ha->lock);
if (dev->dev_type == SAS_END_DEVICE &&
!list_empty(&dev->ssp_dev.eh_list_node)) {
list_del_init(&dev->ssp_dev.eh_list_node);
ha->eh_active--;
}
spin_unlock_irq(&ha->lock);
sas_put_device(dev);
}
void sas_destruct_devices(struct asd_sas_port *port)
{
struct domain_device *dev, *n;
list_for_each_entry_safe(dev, n, &port->destroy_list, disco_list_node) {
list_del_init(&dev->disco_list_node);
sas_remove_children(&dev->rphy->dev);
sas_rphy_delete(dev->rphy);
sas_unregister_common_dev(port, dev);
}
}
static void sas_destruct_ports(struct asd_sas_port *port)
{
struct sas_port *sas_port, *p;
list_for_each_entry_safe(sas_port, p, &port->sas_port_del_list, del_list) {
list_del_init(&sas_port->del_list);
sas_port_delete(sas_port);
}
}
static bool sas_abort_cmd(struct request *req, void *data)
{
struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
struct domain_device *dev = data;
if (dev == cmd_to_domain_dev(cmd))
blk_abort_request(req);
return true;
}
static void sas_abort_device_scsi_cmds(struct domain_device *dev)
{
struct sas_ha_struct *sas_ha = dev->port->ha;
struct Scsi_Host *shost = sas_ha->shost;
if (dev_is_expander(dev->dev_type))
return;
/*
* For removed device with active IOs, the user space applications have
* to spend very long time waiting for the timeout. This is not
* necessary because a removed device will not return the IOs.
* Abort the inflight IOs here so that EH can be quickly kicked in.
*/
blk_mq_tagset_busy_iter(&shost->tag_set, sas_abort_cmd, dev);
}
void sas_unregister_dev(struct asd_sas_port *port, struct domain_device *dev)
{
if (!test_bit(SAS_DEV_DESTROY, &dev->state) &&
!list_empty(&dev->disco_list_node)) {
/* this rphy never saw sas_rphy_add */
list_del_init(&dev->disco_list_node);
sas_rphy_free(dev->rphy);
sas_unregister_common_dev(port, dev);
return;
}
if (!test_and_set_bit(SAS_DEV_DESTROY, &dev->state)) {
if (test_bit(SAS_DEV_GONE, &dev->state))
sas_abort_device_scsi_cmds(dev);
sas_rphy_unlink(dev->rphy);
list_move_tail(&dev->disco_list_node, &port->destroy_list);
}
}
void sas_unregister_domain_devices(struct asd_sas_port *port, int gone)
{
struct domain_device *dev, *n;
list_for_each_entry_safe_reverse(dev, n, &port->dev_list, dev_list_node) {
if (gone)
set_bit(SAS_DEV_GONE, &dev->state);
sas_unregister_dev(port, dev);
}
list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node)
sas_unregister_dev(port, dev);
port->port->rphy = NULL;
}
void sas_device_set_phy(struct domain_device *dev, struct sas_port *port)
{
struct sas_ha_struct *ha;
struct sas_phy *new_phy;
if (!dev)
return;
ha = dev->port->ha;
new_phy = sas_port_get_phy(port);
/* pin and record last seen phy */
spin_lock_irq(&ha->phy_port_lock);
if (new_phy) {
sas_port_put_phy(dev->phy);
dev->phy = new_phy;
}
spin_unlock_irq(&ha->phy_port_lock);
}
/* ---------- Discovery and Revalidation ---------- */
/**
* sas_discover_domain - discover the domain
* @work: work structure embedded in port domain device.
*
* NOTE: this process _must_ quit (return) as soon as any connection
* errors are encountered. Connection recovery is done elsewhere.
* Discover process only interrogates devices in order to discover the
* domain.
*/
static void sas_discover_domain(struct work_struct *work)
{
struct domain_device *dev;
int error = 0;
struct sas_discovery_event *ev = to_sas_discovery_event(work);
struct asd_sas_port *port = ev->port;
clear_bit(DISCE_DISCOVER_DOMAIN, &port->disc.pending);
if (port->port_dev)
return;
error = sas_get_port_device(port);
if (error)
return;
dev = port->port_dev;
pr_debug("DOING DISCOVERY on port %d, pid:%d\n", port->id,
task_pid_nr(current));
switch (dev->dev_type) {
case SAS_END_DEVICE:
error = sas_discover_end_dev(dev);
break;
case SAS_EDGE_EXPANDER_DEVICE:
case SAS_FANOUT_EXPANDER_DEVICE:
error = sas_discover_root_expander(dev);
break;
case SAS_SATA_DEV:
case SAS_SATA_PM:
error = sas_discover_sata(dev);
break;
default:
error = -ENXIO;
pr_err("unhandled device %d\n", dev->dev_type);
break;
}
if (error) {
sas_rphy_free(dev->rphy);
list_del_init(&dev->disco_list_node);
spin_lock_irq(&port->dev_list_lock);
list_del_init(&dev->dev_list_node);
spin_unlock_irq(&port->dev_list_lock);
sas_put_device(dev);
port->port_dev = NULL;
}
sas_probe_devices(port);
pr_debug("DONE DISCOVERY on port %d, pid:%d, result:%d\n", port->id,
task_pid_nr(current), error);
}
static void sas_revalidate_domain(struct work_struct *work)
{
int res = 0;
struct sas_discovery_event *ev = to_sas_discovery_event(work);
struct asd_sas_port *port = ev->port;
struct sas_ha_struct *ha = port->ha;
struct domain_device *ddev = port->port_dev;
/* prevent revalidation from finding sata links in recovery */
mutex_lock(&ha->disco_mutex);
if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) {
pr_debug("REVALIDATION DEFERRED on port %d, pid:%d\n",
port->id, task_pid_nr(current));
goto out;
}
clear_bit(DISCE_REVALIDATE_DOMAIN, &port->disc.pending);
pr_debug("REVALIDATING DOMAIN on port %d, pid:%d\n", port->id,
task_pid_nr(current));
if (ddev && dev_is_expander(ddev->dev_type))
res = sas_ex_revalidate_domain(ddev);
pr_debug("done REVALIDATING DOMAIN on port %d, pid:%d, res 0x%x\n",
port->id, task_pid_nr(current), res);
out:
mutex_unlock(&ha->disco_mutex);
sas_destruct_devices(port);
sas_destruct_ports(port);
sas_probe_devices(port);
}
/* ---------- Events ---------- */
static void sas_chain_work(struct sas_ha_struct *ha, struct sas_work *sw)
{
/* chained work is not subject to SA_HA_DRAINING or
* SAS_HA_REGISTERED, because it is either submitted in the
* workqueue, or known to be submitted from a context that is
* not racing against draining
*/
queue_work(ha->disco_q, &sw->work);
}
static void sas_chain_event(int event, unsigned long *pending,
struct sas_work *sw,
struct sas_ha_struct *ha)
{
if (!test_and_set_bit(event, pending)) {
unsigned long flags;
spin_lock_irqsave(&ha->lock, flags);
sas_chain_work(ha, sw);
spin_unlock_irqrestore(&ha->lock, flags);
}
}
void sas_discover_event(struct asd_sas_port *port, enum discover_event ev)
{
struct sas_discovery *disc;
if (!port)
return;
disc = &port->disc;
BUG_ON(ev >= DISC_NUM_EVENTS);
sas_chain_event(ev, &disc->pending, &disc->disc_work[ev].work, port->ha);
}
/**
* sas_init_disc - initialize the discovery struct in the port
* @disc: port discovery structure
* @port: pointer to struct port
*
* Called when the ports are being initialized.
*/
void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *port)
{
int i;
static const work_func_t sas_event_fns[DISC_NUM_EVENTS] = {
[DISCE_DISCOVER_DOMAIN] = sas_discover_domain,
[DISCE_REVALIDATE_DOMAIN] = sas_revalidate_domain,
[DISCE_SUSPEND] = sas_suspend_devices,
[DISCE_RESUME] = sas_resume_devices,
};
disc->pending = 0;
for (i = 0; i < DISC_NUM_EVENTS; i++) {
INIT_SAS_WORK(&disc->disc_work[i].work, sas_event_fns[i]);
disc->disc_work[i].port = port;
}
}
Codebase Browser
linux