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Diffstat (limited to '')
| -rw-r--r-- | drivers/scsi/scsi_transport_srp.c | 916 |
1 files changed, 916 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_transport_srp.c b/drivers/scsi/scsi_transport_srp.c new file mode 100644 index 000000000..9ac89462a --- /dev/null +++ b/drivers/scsi/scsi_transport_srp.c @@ -0,0 +1,916 @@ +/* + * SCSI RDMA (SRP) transport class + * + * Copyright (C) 2007 FUJITA Tomonori <tomof@acm.org> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + */ +#include <linux/init.h> +#include <linux/module.h> +#include <linux/jiffies.h> +#include <linux/err.h> +#include <linux/slab.h> +#include <linux/string.h> + +#include <scsi/scsi.h> +#include <scsi/scsi_cmnd.h> +#include <scsi/scsi_device.h> +#include <scsi/scsi_host.h> +#include <scsi/scsi_transport.h> +#include <scsi/scsi_transport_srp.h> +#include "scsi_priv.h" + +struct srp_host_attrs { + atomic_t next_port_id; +}; +#define to_srp_host_attrs(host) ((struct srp_host_attrs *)(host)->shost_data) + +#define SRP_HOST_ATTRS 0 +#define SRP_RPORT_ATTRS 8 + +struct srp_internal { + struct scsi_transport_template t; + struct srp_function_template *f; + + struct device_attribute *host_attrs[SRP_HOST_ATTRS + 1]; + + struct device_attribute *rport_attrs[SRP_RPORT_ATTRS + 1]; + struct transport_container rport_attr_cont; +}; + +static int scsi_is_srp_rport(const struct device *dev); + +#define to_srp_internal(tmpl) container_of(tmpl, struct srp_internal, t) + +#define dev_to_rport(d) container_of(d, struct srp_rport, dev) +#define transport_class_to_srp_rport(dev) dev_to_rport((dev)->parent) +static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r) +{ + return dev_to_shost(r->dev.parent); +} + +static int find_child_rport(struct device *dev, void *data) +{ + struct device **child = data; + + if (scsi_is_srp_rport(dev)) { + WARN_ON_ONCE(*child); + *child = dev; + } + return 0; +} + +static inline struct srp_rport *shost_to_rport(struct Scsi_Host *shost) +{ + struct device *child = NULL; + + WARN_ON_ONCE(device_for_each_child(&shost->shost_gendev, &child, + find_child_rport) < 0); + return child ? dev_to_rport(child) : NULL; +} + +/** + * srp_tmo_valid() - check timeout combination validity + * @reconnect_delay: Reconnect delay in seconds. + * @fast_io_fail_tmo: Fast I/O fail timeout in seconds. + * @dev_loss_tmo: Device loss timeout in seconds. + * + * The combination of the timeout parameters must be such that SCSI commands + * are finished in a reasonable time. Hence do not allow the fast I/O fail + * timeout to exceed SCSI_DEVICE_BLOCK_MAX_TIMEOUT nor allow dev_loss_tmo to + * exceed that limit if failing I/O fast has been disabled. Furthermore, these + * parameters must be such that multipath can detect failed paths timely. + * Hence do not allow all three parameters to be disabled simultaneously. + */ +int srp_tmo_valid(int reconnect_delay, int fast_io_fail_tmo, long dev_loss_tmo) +{ + if (reconnect_delay < 0 && fast_io_fail_tmo < 0 && dev_loss_tmo < 0) + return -EINVAL; + if (reconnect_delay == 0) + return -EINVAL; + if (fast_io_fail_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT) + return -EINVAL; + if (fast_io_fail_tmo < 0 && + dev_loss_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT) + return -EINVAL; + if (dev_loss_tmo >= LONG_MAX / HZ) + return -EINVAL; + if (fast_io_fail_tmo >= 0 && dev_loss_tmo >= 0 && + fast_io_fail_tmo >= dev_loss_tmo) + return -EINVAL; + return 0; +} +EXPORT_SYMBOL_GPL(srp_tmo_valid); + +static int srp_host_setup(struct transport_container *tc, struct device *dev, + struct device *cdev) +{ + struct Scsi_Host *shost = dev_to_shost(dev); + struct srp_host_attrs *srp_host = to_srp_host_attrs(shost); + + atomic_set(&srp_host->next_port_id, 0); + return 0; +} + +static DECLARE_TRANSPORT_CLASS(srp_host_class, "srp_host", srp_host_setup, + NULL, NULL); + +static DECLARE_TRANSPORT_CLASS(srp_rport_class, "srp_remote_ports", + NULL, NULL, NULL); + +static ssize_t +show_srp_rport_id(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct srp_rport *rport = transport_class_to_srp_rport(dev); + return sprintf(buf, "%16phC\n", rport->port_id); +} + +static DEVICE_ATTR(port_id, S_IRUGO, show_srp_rport_id, NULL); + +static const struct { + u32 value; + char *name; +} srp_rport_role_names[] = { + {SRP_RPORT_ROLE_INITIATOR, "SRP Initiator"}, + {SRP_RPORT_ROLE_TARGET, "SRP Target"}, +}; + +static ssize_t +show_srp_rport_roles(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct srp_rport *rport = transport_class_to_srp_rport(dev); + int i; + char *name = NULL; + + for (i = 0; i < ARRAY_SIZE(srp_rport_role_names); i++) + if (srp_rport_role_names[i].value == rport->roles) { + name = srp_rport_role_names[i].name; + break; + } + return sprintf(buf, "%s\n", name ? : "unknown"); +} + +static DEVICE_ATTR(roles, S_IRUGO, show_srp_rport_roles, NULL); + +static ssize_t store_srp_rport_delete(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct srp_rport *rport = transport_class_to_srp_rport(dev); + struct Scsi_Host *shost = dev_to_shost(dev); + struct srp_internal *i = to_srp_internal(shost->transportt); + + if (i->f->rport_delete) { + i->f->rport_delete(rport); + return count; + } else { + return -ENOSYS; + } +} + +static DEVICE_ATTR(delete, S_IWUSR, NULL, store_srp_rport_delete); + +static ssize_t show_srp_rport_state(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + static const char *const state_name[] = { + [SRP_RPORT_RUNNING] = "running", + [SRP_RPORT_BLOCKED] = "blocked", + [SRP_RPORT_FAIL_FAST] = "fail-fast", + [SRP_RPORT_LOST] = "lost", + }; + struct srp_rport *rport = transport_class_to_srp_rport(dev); + enum srp_rport_state state = rport->state; + + return sprintf(buf, "%s\n", + (unsigned)state < ARRAY_SIZE(state_name) ? + state_name[state] : "???"); +} + +static DEVICE_ATTR(state, S_IRUGO, show_srp_rport_state, NULL); + +static ssize_t srp_show_tmo(char *buf, int tmo) +{ + return tmo >= 0 ? sprintf(buf, "%d\n", tmo) : sprintf(buf, "off\n"); +} + +int srp_parse_tmo(int *tmo, const char *buf) +{ + int res = 0; + + if (strncmp(buf, "off", 3) != 0) + res = kstrtoint(buf, 0, tmo); + else + *tmo = -1; + + return res; +} +EXPORT_SYMBOL(srp_parse_tmo); + +static ssize_t show_reconnect_delay(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct srp_rport *rport = transport_class_to_srp_rport(dev); + + return srp_show_tmo(buf, rport->reconnect_delay); +} + +static ssize_t store_reconnect_delay(struct device *dev, + struct device_attribute *attr, + const char *buf, const size_t count) +{ + struct srp_rport *rport = transport_class_to_srp_rport(dev); + int res, delay; + + res = srp_parse_tmo(&delay, buf); + if (res) + goto out; + res = srp_tmo_valid(delay, rport->fast_io_fail_tmo, + rport->dev_loss_tmo); + if (res) + goto out; + + if (rport->reconnect_delay <= 0 && delay > 0 && + rport->state != SRP_RPORT_RUNNING) { + queue_delayed_work(system_long_wq, &rport->reconnect_work, + delay * HZ); + } else if (delay <= 0) { + cancel_delayed_work(&rport->reconnect_work); + } + rport->reconnect_delay = delay; + res = count; + +out: + return res; +} + +static DEVICE_ATTR(reconnect_delay, S_IRUGO | S_IWUSR, show_reconnect_delay, + store_reconnect_delay); + +static ssize_t show_failed_reconnects(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct srp_rport *rport = transport_class_to_srp_rport(dev); + + return sprintf(buf, "%d\n", rport->failed_reconnects); +} + +static DEVICE_ATTR(failed_reconnects, S_IRUGO, show_failed_reconnects, NULL); + +static ssize_t show_srp_rport_fast_io_fail_tmo(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct srp_rport *rport = transport_class_to_srp_rport(dev); + + return srp_show_tmo(buf, rport->fast_io_fail_tmo); +} + +static ssize_t store_srp_rport_fast_io_fail_tmo(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct srp_rport *rport = transport_class_to_srp_rport(dev); + int res; + int fast_io_fail_tmo; + + res = srp_parse_tmo(&fast_io_fail_tmo, buf); + if (res) + goto out; + res = srp_tmo_valid(rport->reconnect_delay, fast_io_fail_tmo, + rport->dev_loss_tmo); + if (res) + goto out; + rport->fast_io_fail_tmo = fast_io_fail_tmo; + res = count; + +out: + return res; +} + +static DEVICE_ATTR(fast_io_fail_tmo, S_IRUGO | S_IWUSR, + show_srp_rport_fast_io_fail_tmo, + store_srp_rport_fast_io_fail_tmo); + +static ssize_t show_srp_rport_dev_loss_tmo(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct srp_rport *rport = transport_class_to_srp_rport(dev); + + return srp_show_tmo(buf, rport->dev_loss_tmo); +} + +static ssize_t store_srp_rport_dev_loss_tmo(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct srp_rport *rport = transport_class_to_srp_rport(dev); + int res; + int dev_loss_tmo; + + res = srp_parse_tmo(&dev_loss_tmo, buf); + if (res) + goto out; + res = srp_tmo_valid(rport->reconnect_delay, rport->fast_io_fail_tmo, + dev_loss_tmo); + if (res) + goto out; + rport->dev_loss_tmo = dev_loss_tmo; + res = count; + +out: + return res; +} + +static DEVICE_ATTR(dev_loss_tmo, S_IRUGO | S_IWUSR, + show_srp_rport_dev_loss_tmo, + store_srp_rport_dev_loss_tmo); + +static int srp_rport_set_state(struct srp_rport *rport, + enum srp_rport_state new_state) +{ + enum srp_rport_state old_state = rport->state; + + lockdep_assert_held(&rport->mutex); + + switch (new_state) { + case SRP_RPORT_RUNNING: + switch (old_state) { + case SRP_RPORT_LOST: + goto invalid; + default: + break; + } + break; + case SRP_RPORT_BLOCKED: + switch (old_state) { + case SRP_RPORT_RUNNING: + break; + default: + goto invalid; + } + break; + case SRP_RPORT_FAIL_FAST: + switch (old_state) { + case SRP_RPORT_LOST: + goto invalid; + default: + break; + } + break; + case SRP_RPORT_LOST: + break; + } + rport->state = new_state; + return 0; + +invalid: + return -EINVAL; +} + +/** + * srp_reconnect_work() - reconnect and schedule a new attempt if necessary + * @work: Work structure used for scheduling this operation. + */ +static void srp_reconnect_work(struct work_struct *work) +{ + struct srp_rport *rport = container_of(to_delayed_work(work), + struct srp_rport, reconnect_work); + struct Scsi_Host *shost = rport_to_shost(rport); + int delay, res; + + res = srp_reconnect_rport(rport); + if (res != 0) { + shost_printk(KERN_ERR, shost, + "reconnect attempt %d failed (%d)\n", + ++rport->failed_reconnects, res); + delay = rport->reconnect_delay * + min(100, max(1, rport->failed_reconnects - 10)); + if (delay > 0) + queue_delayed_work(system_long_wq, + &rport->reconnect_work, delay * HZ); + } +} + +static void __rport_fail_io_fast(struct srp_rport *rport) +{ + struct Scsi_Host *shost = rport_to_shost(rport); + struct srp_internal *i; + + lockdep_assert_held(&rport->mutex); + + if (srp_rport_set_state(rport, SRP_RPORT_FAIL_FAST)) + return; + /* + * Call scsi_target_block() to wait for ongoing shost->queuecommand() + * calls before invoking i->f->terminate_rport_io(). + */ + scsi_target_block(rport->dev.parent); + scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE); + + /* Involve the LLD if possible to terminate all I/O on the rport. */ + i = to_srp_internal(shost->transportt); + if (i->f->terminate_rport_io) + i->f->terminate_rport_io(rport); +} + +/** + * rport_fast_io_fail_timedout() - fast I/O failure timeout handler + * @work: Work structure used for scheduling this operation. + */ +static void rport_fast_io_fail_timedout(struct work_struct *work) +{ + struct srp_rport *rport = container_of(to_delayed_work(work), + struct srp_rport, fast_io_fail_work); + struct Scsi_Host *shost = rport_to_shost(rport); + + pr_info("fast_io_fail_tmo expired for SRP %s / %s.\n", + dev_name(&rport->dev), dev_name(&shost->shost_gendev)); + + mutex_lock(&rport->mutex); + if (rport->state == SRP_RPORT_BLOCKED) + __rport_fail_io_fast(rport); + mutex_unlock(&rport->mutex); +} + +/** + * rport_dev_loss_timedout() - device loss timeout handler + * @work: Work structure used for scheduling this operation. + */ +static void rport_dev_loss_timedout(struct work_struct *work) +{ + struct srp_rport *rport = container_of(to_delayed_work(work), + struct srp_rport, dev_loss_work); + struct Scsi_Host *shost = rport_to_shost(rport); + struct srp_internal *i = to_srp_internal(shost->transportt); + + pr_info("dev_loss_tmo expired for SRP %s / %s.\n", + dev_name(&rport->dev), dev_name(&shost->shost_gendev)); + + mutex_lock(&rport->mutex); + WARN_ON(srp_rport_set_state(rport, SRP_RPORT_LOST) != 0); + scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE); + mutex_unlock(&rport->mutex); + + i->f->rport_delete(rport); +} + +static void __srp_start_tl_fail_timers(struct srp_rport *rport) +{ + struct Scsi_Host *shost = rport_to_shost(rport); + int delay, fast_io_fail_tmo, dev_loss_tmo; + + lockdep_assert_held(&rport->mutex); + + delay = rport->reconnect_delay; + fast_io_fail_tmo = rport->fast_io_fail_tmo; + dev_loss_tmo = rport->dev_loss_tmo; + pr_debug("%s current state: %d\n", dev_name(&shost->shost_gendev), + rport->state); + + if (rport->state == SRP_RPORT_LOST) + return; + if (delay > 0) + queue_delayed_work(system_long_wq, &rport->reconnect_work, + 1UL * delay * HZ); + if ((fast_io_fail_tmo >= 0 || dev_loss_tmo >= 0) && + srp_rport_set_state(rport, SRP_RPORT_BLOCKED) == 0) { + pr_debug("%s new state: %d\n", dev_name(&shost->shost_gendev), + rport->state); + scsi_target_block(&shost->shost_gendev); + if (fast_io_fail_tmo >= 0) + queue_delayed_work(system_long_wq, + &rport->fast_io_fail_work, + 1UL * fast_io_fail_tmo * HZ); + if (dev_loss_tmo >= 0) + queue_delayed_work(system_long_wq, + &rport->dev_loss_work, + 1UL * dev_loss_tmo * HZ); + } +} + +/** + * srp_start_tl_fail_timers() - start the transport layer failure timers + * @rport: SRP target port. + * + * Start the transport layer fast I/O failure and device loss timers. Do not + * modify a timer that was already started. + */ +void srp_start_tl_fail_timers(struct srp_rport *rport) +{ + mutex_lock(&rport->mutex); + __srp_start_tl_fail_timers(rport); + mutex_unlock(&rport->mutex); +} +EXPORT_SYMBOL(srp_start_tl_fail_timers); + +/** + * srp_reconnect_rport() - reconnect to an SRP target port + * @rport: SRP target port. + * + * Blocks SCSI command queueing before invoking reconnect() such that + * queuecommand() won't be invoked concurrently with reconnect() from outside + * the SCSI EH. This is important since a reconnect() implementation may + * reallocate resources needed by queuecommand(). + * + * Notes: + * - This function neither waits until outstanding requests have finished nor + * tries to abort these. It is the responsibility of the reconnect() + * function to finish outstanding commands before reconnecting to the target + * port. + * - It is the responsibility of the caller to ensure that the resources + * reallocated by the reconnect() function won't be used while this function + * is in progress. One possible strategy is to invoke this function from + * the context of the SCSI EH thread only. Another possible strategy is to + * lock the rport mutex inside each SCSI LLD callback that can be invoked by + * the SCSI EH (the scsi_host_template.eh_*() functions and also the + * scsi_host_template.queuecommand() function). + */ +int srp_reconnect_rport(struct srp_rport *rport) +{ + struct Scsi_Host *shost = rport_to_shost(rport); + struct srp_internal *i = to_srp_internal(shost->transportt); + struct scsi_device *sdev; + int res; + + pr_debug("SCSI host %s\n", dev_name(&shost->shost_gendev)); + + res = mutex_lock_interruptible(&rport->mutex); + if (res) + goto out; + if (rport->state != SRP_RPORT_FAIL_FAST && rport->state != SRP_RPORT_LOST) + /* + * sdev state must be SDEV_TRANSPORT_OFFLINE, transition + * to SDEV_BLOCK is illegal. Calling scsi_target_unblock() + * later is ok though, scsi_internal_device_unblock_nowait() + * treats SDEV_TRANSPORT_OFFLINE like SDEV_BLOCK. + */ + scsi_target_block(&shost->shost_gendev); + res = rport->state != SRP_RPORT_LOST ? i->f->reconnect(rport) : -ENODEV; + pr_debug("%s (state %d): transport.reconnect() returned %d\n", + dev_name(&shost->shost_gendev), rport->state, res); + if (res == 0) { + cancel_delayed_work(&rport->fast_io_fail_work); + cancel_delayed_work(&rport->dev_loss_work); + + rport->failed_reconnects = 0; + srp_rport_set_state(rport, SRP_RPORT_RUNNING); + scsi_target_unblock(&shost->shost_gendev, SDEV_RUNNING); + /* + * If the SCSI error handler has offlined one or more devices, + * invoking scsi_target_unblock() won't change the state of + * these devices into running so do that explicitly. + */ + shost_for_each_device(sdev, shost) { + mutex_lock(&sdev->state_mutex); + if (sdev->sdev_state == SDEV_OFFLINE) + sdev->sdev_state = SDEV_RUNNING; + mutex_unlock(&sdev->state_mutex); + } + } else if (rport->state == SRP_RPORT_RUNNING) { + /* + * srp_reconnect_rport() has been invoked with fast_io_fail + * and dev_loss off. Mark the port as failed and start the TL + * failure timers if these had not yet been started. + */ + __rport_fail_io_fast(rport); + scsi_target_unblock(&shost->shost_gendev, + SDEV_TRANSPORT_OFFLINE); + __srp_start_tl_fail_timers(rport); + } else if (rport->state != SRP_RPORT_BLOCKED) { + scsi_target_unblock(&shost->shost_gendev, + SDEV_TRANSPORT_OFFLINE); + } + mutex_unlock(&rport->mutex); + +out: + return res; +} +EXPORT_SYMBOL(srp_reconnect_rport); + +/** + * srp_timed_out() - SRP transport intercept of the SCSI timeout EH + * @scmd: SCSI command. + * + * If a timeout occurs while an rport is in the blocked state, ask the SCSI + * EH to continue waiting (BLK_EH_RESET_TIMER). Otherwise let the SCSI core + * handle the timeout (BLK_EH_DONE). + * + * Note: This function is called from soft-IRQ context and with the request + * queue lock held. + */ +enum blk_eh_timer_return srp_timed_out(struct scsi_cmnd *scmd) +{ + struct scsi_device *sdev = scmd->device; + struct Scsi_Host *shost = sdev->host; + struct srp_internal *i = to_srp_internal(shost->transportt); + struct srp_rport *rport = shost_to_rport(shost); + + pr_debug("timeout for sdev %s\n", dev_name(&sdev->sdev_gendev)); + return rport && rport->fast_io_fail_tmo < 0 && + rport->dev_loss_tmo < 0 && + i->f->reset_timer_if_blocked && scsi_device_blocked(sdev) ? + BLK_EH_RESET_TIMER : BLK_EH_DONE; +} +EXPORT_SYMBOL(srp_timed_out); + +static void srp_rport_release(struct device *dev) +{ + struct srp_rport *rport = dev_to_rport(dev); + + put_device(dev->parent); + kfree(rport); +} + +static int scsi_is_srp_rport(const struct device *dev) +{ + return dev->release == srp_rport_release; +} + +static int srp_rport_match(struct attribute_container *cont, + struct device *dev) +{ + struct Scsi_Host *shost; + struct srp_internal *i; + + if (!scsi_is_srp_rport(dev)) + return 0; + + shost = dev_to_shost(dev->parent); + if (!shost->transportt) + return 0; + if (shost->transportt->host_attrs.ac.class != &srp_host_class.class) + return 0; + + i = to_srp_internal(shost->transportt); + return &i->rport_attr_cont.ac == cont; +} + +static int srp_host_match(struct attribute_container *cont, struct device *dev) +{ + struct Scsi_Host *shost; + struct srp_internal *i; + + if (!scsi_is_host_device(dev)) + return 0; + + shost = dev_to_shost(dev); + if (!shost->transportt) + return 0; + if (shost->transportt->host_attrs.ac.class != &srp_host_class.class) + return 0; + + i = to_srp_internal(shost->transportt); + return &i->t.host_attrs.ac == cont; +} + +/** + * srp_rport_get() - increment rport reference count + * @rport: SRP target port. + */ +void srp_rport_get(struct srp_rport *rport) +{ + get_device(&rport->dev); +} +EXPORT_SYMBOL(srp_rport_get); + +/** + * srp_rport_put() - decrement rport reference count + * @rport: SRP target port. + */ +void srp_rport_put(struct srp_rport *rport) +{ + put_device(&rport->dev); +} +EXPORT_SYMBOL(srp_rport_put); + +/** + * srp_rport_add - add a SRP remote port to the device hierarchy + * @shost: scsi host the remote port is connected to. + * @ids: The port id for the remote port. + * + * Publishes a port to the rest of the system. + */ +struct srp_rport *srp_rport_add(struct Scsi_Host *shost, + struct srp_rport_identifiers *ids) +{ + struct srp_rport *rport; + struct device *parent = &shost->shost_gendev; + struct srp_internal *i = to_srp_internal(shost->transportt); + int id, ret; + + rport = kzalloc(sizeof(*rport), GFP_KERNEL); + if (!rport) + return ERR_PTR(-ENOMEM); + + mutex_init(&rport->mutex); + + device_initialize(&rport->dev); + + rport->dev.parent = get_device(parent); + rport->dev.release = srp_rport_release; + + memcpy(rport->port_id, ids->port_id, sizeof(rport->port_id)); + rport->roles = ids->roles; + + if (i->f->reconnect) + rport->reconnect_delay = i->f->reconnect_delay ? + *i->f->reconnect_delay : 10; + INIT_DELAYED_WORK(&rport->reconnect_work, srp_reconnect_work); + rport->fast_io_fail_tmo = i->f->fast_io_fail_tmo ? + *i->f->fast_io_fail_tmo : 15; + rport->dev_loss_tmo = i->f->dev_loss_tmo ? *i->f->dev_loss_tmo : 60; + INIT_DELAYED_WORK(&rport->fast_io_fail_work, + rport_fast_io_fail_timedout); + INIT_DELAYED_WORK(&rport->dev_loss_work, rport_dev_loss_timedout); + + id = atomic_inc_return(&to_srp_host_attrs(shost)->next_port_id); + dev_set_name(&rport->dev, "port-%d:%d", shost->host_no, id); + + transport_setup_device(&rport->dev); + + ret = device_add(&rport->dev); + if (ret) { + transport_destroy_device(&rport->dev); + put_device(&rport->dev); + return ERR_PTR(ret); + } + + transport_add_device(&rport->dev); + transport_configure_device(&rport->dev); + + return rport; +} +EXPORT_SYMBOL_GPL(srp_rport_add); + +/** + * srp_rport_del - remove a SRP remote port + * @rport: SRP remote port to remove + * + * Removes the specified SRP remote port. + */ +void srp_rport_del(struct srp_rport *rport) +{ + struct device *dev = &rport->dev; + + transport_remove_device(dev); + device_del(dev); + transport_destroy_device(dev); + + put_device(dev); +} +EXPORT_SYMBOL_GPL(srp_rport_del); + +static int do_srp_rport_del(struct device *dev, void *data) +{ + if (scsi_is_srp_rport(dev)) + srp_rport_del(dev_to_rport(dev)); + return 0; +} + +/** + * srp_remove_host - tear down a Scsi_Host's SRP data structures + * @shost: Scsi Host that is torn down + * + * Removes all SRP remote ports for a given Scsi_Host. + * Must be called just before scsi_remove_host for SRP HBAs. + */ +void srp_remove_host(struct Scsi_Host *shost) +{ + device_for_each_child(&shost->shost_gendev, NULL, do_srp_rport_del); +} +EXPORT_SYMBOL_GPL(srp_remove_host); + +/** + * srp_stop_rport_timers - stop the transport layer recovery timers + * @rport: SRP remote port for which to stop the timers. + * + * Must be called after srp_remove_host() and scsi_remove_host(). The caller + * must hold a reference on the rport (rport->dev) and on the SCSI host + * (rport->dev.parent). + */ +void srp_stop_rport_timers(struct srp_rport *rport) +{ + mutex_lock(&rport->mutex); + if (rport->state == SRP_RPORT_BLOCKED) + __rport_fail_io_fast(rport); + srp_rport_set_state(rport, SRP_RPORT_LOST); + mutex_unlock(&rport->mutex); + + cancel_delayed_work_sync(&rport->reconnect_work); + cancel_delayed_work_sync(&rport->fast_io_fail_work); + cancel_delayed_work_sync(&rport->dev_loss_work); +} +EXPORT_SYMBOL_GPL(srp_stop_rport_timers); + +/** + * srp_attach_transport - instantiate SRP transport template + * @ft: SRP transport class function template + */ +struct scsi_transport_template * +srp_attach_transport(struct srp_function_template *ft) +{ + int count; + struct srp_internal *i; + + i = kzalloc(sizeof(*i), GFP_KERNEL); + if (!i) + return NULL; + + i->t.host_size = sizeof(struct srp_host_attrs); + i->t.host_attrs.ac.attrs = &i->host_attrs[0]; + i->t.host_attrs.ac.class = &srp_host_class.class; + i->t.host_attrs.ac.match = srp_host_match; + i->host_attrs[0] = NULL; + transport_container_register(&i->t.host_attrs); + + i->rport_attr_cont.ac.attrs = &i->rport_attrs[0]; + i->rport_attr_cont.ac.class = &srp_rport_class.class; + i->rport_attr_cont.ac.match = srp_rport_match; + + count = 0; + i->rport_attrs[count++] = &dev_attr_port_id; + i->rport_attrs[count++] = &dev_attr_roles; + if (ft->has_rport_state) { + i->rport_attrs[count++] = &dev_attr_state; + i->rport_attrs[count++] = &dev_attr_fast_io_fail_tmo; + i->rport_attrs[count++] = &dev_attr_dev_loss_tmo; + } + if (ft->reconnect) { + i->rport_attrs[count++] = &dev_attr_reconnect_delay; + i->rport_attrs[count++] = &dev_attr_failed_reconnects; + } + if (ft->rport_delete) + i->rport_attrs[count++] = &dev_attr_delete; + i->rport_attrs[count++] = NULL; + BUG_ON(count > ARRAY_SIZE(i->rport_attrs)); + + transport_container_register(&i->rport_attr_cont); + + i->f = ft; + + return &i->t; +} +EXPORT_SYMBOL_GPL(srp_attach_transport); + +/** + * srp_release_transport - release SRP transport template instance + * @t: transport template instance + */ +void srp_release_transport(struct scsi_transport_template *t) +{ + struct srp_internal *i = to_srp_internal(t); + + transport_container_unregister(&i->t.host_attrs); + transport_container_unregister(&i->rport_attr_cont); + + kfree(i); +} +EXPORT_SYMBOL_GPL(srp_release_transport); + +static __init int srp_transport_init(void) +{ + int ret; + + ret = transport_class_register(&srp_host_class); + if (ret) + return ret; + ret = transport_class_register(&srp_rport_class); + if (ret) + goto unregister_host_class; + + return 0; +unregister_host_class: + transport_class_unregister(&srp_host_class); + return ret; +} + +static void __exit srp_transport_exit(void) +{ + transport_class_unregister(&srp_host_class); + transport_class_unregister(&srp_rport_class); +} + +MODULE_AUTHOR("FUJITA Tomonori"); +MODULE_DESCRIPTION("SRP Transport Attributes"); +MODULE_LICENSE("GPL"); + +module_init(srp_transport_init); +module_exit(srp_transport_exit); |