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-rw-r--r--drivers/scsi/libsas/sas_discover.c584
1 files changed, 584 insertions, 0 deletions
diff --git a/drivers/scsi/libsas/sas_discover.c b/drivers/scsi/libsas/sas_discover.c
new file mode 100644
index 000000000..d5bc1314c
--- /dev/null
+++ b/drivers/scsi/libsas/sas_discover.c
@@ -0,0 +1,584 @@
+// 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 <luben_tuikov@adaptec.com>
+ */
+
+#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->core.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->core.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->core.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().
+ */
+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_sas_tport_delete(dev->sata_dev.ap);
+ ata_sas_port_destroy(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);
+ }
+}
+
+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)) {
+ 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:
+#ifdef CONFIG_SCSI_SAS_ATA
+ error = sas_discover_sata(dev);
+ break;
+#else
+ pr_notice("ATA device seen but CONFIG_SCSI_SAS_ATA=N so cannot attach\n");
+ fallthrough;
+#endif
+ /* Fall through - only for the #else condition above. */
+ 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;
+ }
+}