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900 lines
24 KiB
900 lines
24 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* SCSI RDMA (SRP) transport class |
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* |
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* Copyright (C) 2007 FUJITA Tomonori <[email protected]> |
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*/ |
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#include <linux/init.h> |
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#include <linux/module.h> |
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#include <linux/jiffies.h> |
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#include <linux/err.h> |
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#include <linux/slab.h> |
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#include <linux/string.h> |
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#include <scsi/scsi.h> |
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#include <scsi/scsi_cmnd.h> |
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#include <scsi/scsi_device.h> |
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#include <scsi/scsi_host.h> |
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#include <scsi/scsi_transport.h> |
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#include <scsi/scsi_transport_srp.h> |
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#include "scsi_priv.h" |
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struct srp_host_attrs { |
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atomic_t next_port_id; |
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}; |
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#define to_srp_host_attrs(host) ((struct srp_host_attrs *)(host)->shost_data) |
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#define SRP_HOST_ATTRS 0 |
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#define SRP_RPORT_ATTRS 8 |
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struct srp_internal { |
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struct scsi_transport_template t; |
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struct srp_function_template *f; |
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struct device_attribute *host_attrs[SRP_HOST_ATTRS + 1]; |
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struct device_attribute *rport_attrs[SRP_RPORT_ATTRS + 1]; |
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struct transport_container rport_attr_cont; |
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}; |
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static int scsi_is_srp_rport(const struct device *dev); |
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#define to_srp_internal(tmpl) container_of(tmpl, struct srp_internal, t) |
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#define dev_to_rport(d) container_of(d, struct srp_rport, dev) |
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#define transport_class_to_srp_rport(dev) dev_to_rport((dev)->parent) |
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static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r) |
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{ |
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return dev_to_shost(r->dev.parent); |
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} |
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static int find_child_rport(struct device *dev, void *data) |
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{ |
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struct device **child = data; |
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if (scsi_is_srp_rport(dev)) { |
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WARN_ON_ONCE(*child); |
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*child = dev; |
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} |
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return 0; |
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} |
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static inline struct srp_rport *shost_to_rport(struct Scsi_Host *shost) |
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{ |
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struct device *child = NULL; |
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WARN_ON_ONCE(device_for_each_child(&shost->shost_gendev, &child, |
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find_child_rport) < 0); |
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return child ? dev_to_rport(child) : NULL; |
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} |
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/** |
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* srp_tmo_valid() - check timeout combination validity |
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* @reconnect_delay: Reconnect delay in seconds. |
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* @fast_io_fail_tmo: Fast I/O fail timeout in seconds. |
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* @dev_loss_tmo: Device loss timeout in seconds. |
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* |
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* The combination of the timeout parameters must be such that SCSI commands |
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* are finished in a reasonable time. Hence do not allow the fast I/O fail |
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* timeout to exceed SCSI_DEVICE_BLOCK_MAX_TIMEOUT nor allow dev_loss_tmo to |
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* exceed that limit if failing I/O fast has been disabled. Furthermore, these |
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* parameters must be such that multipath can detect failed paths timely. |
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* Hence do not allow all three parameters to be disabled simultaneously. |
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*/ |
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int srp_tmo_valid(int reconnect_delay, int fast_io_fail_tmo, long dev_loss_tmo) |
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{ |
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if (reconnect_delay < 0 && fast_io_fail_tmo < 0 && dev_loss_tmo < 0) |
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return -EINVAL; |
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if (reconnect_delay == 0) |
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return -EINVAL; |
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if (fast_io_fail_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT) |
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return -EINVAL; |
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if (fast_io_fail_tmo < 0 && |
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dev_loss_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT) |
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return -EINVAL; |
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if (dev_loss_tmo >= LONG_MAX / HZ) |
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return -EINVAL; |
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if (fast_io_fail_tmo >= 0 && dev_loss_tmo >= 0 && |
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fast_io_fail_tmo >= dev_loss_tmo) |
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return -EINVAL; |
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return 0; |
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} |
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EXPORT_SYMBOL_GPL(srp_tmo_valid); |
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static int srp_host_setup(struct transport_container *tc, struct device *dev, |
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struct device *cdev) |
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{ |
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struct Scsi_Host *shost = dev_to_shost(dev); |
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struct srp_host_attrs *srp_host = to_srp_host_attrs(shost); |
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atomic_set(&srp_host->next_port_id, 0); |
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return 0; |
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} |
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static DECLARE_TRANSPORT_CLASS(srp_host_class, "srp_host", srp_host_setup, |
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NULL, NULL); |
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static DECLARE_TRANSPORT_CLASS(srp_rport_class, "srp_remote_ports", |
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NULL, NULL, NULL); |
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static ssize_t |
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show_srp_rport_id(struct device *dev, struct device_attribute *attr, |
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char *buf) |
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{ |
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struct srp_rport *rport = transport_class_to_srp_rport(dev); |
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return sprintf(buf, "%16phC\n", rport->port_id); |
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} |
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static DEVICE_ATTR(port_id, S_IRUGO, show_srp_rport_id, NULL); |
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static const struct { |
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u32 value; |
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char *name; |
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} srp_rport_role_names[] = { |
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{SRP_RPORT_ROLE_INITIATOR, "SRP Initiator"}, |
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{SRP_RPORT_ROLE_TARGET, "SRP Target"}, |
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}; |
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static ssize_t |
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show_srp_rport_roles(struct device *dev, struct device_attribute *attr, |
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char *buf) |
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{ |
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struct srp_rport *rport = transport_class_to_srp_rport(dev); |
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int i; |
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char *name = NULL; |
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for (i = 0; i < ARRAY_SIZE(srp_rport_role_names); i++) |
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if (srp_rport_role_names[i].value == rport->roles) { |
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name = srp_rport_role_names[i].name; |
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break; |
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} |
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return sprintf(buf, "%s\n", name ? : "unknown"); |
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} |
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static DEVICE_ATTR(roles, S_IRUGO, show_srp_rport_roles, NULL); |
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static ssize_t store_srp_rport_delete(struct device *dev, |
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struct device_attribute *attr, |
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const char *buf, size_t count) |
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{ |
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struct srp_rport *rport = transport_class_to_srp_rport(dev); |
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struct Scsi_Host *shost = dev_to_shost(dev); |
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struct srp_internal *i = to_srp_internal(shost->transportt); |
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if (i->f->rport_delete) { |
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i->f->rport_delete(rport); |
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return count; |
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} else { |
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return -ENOSYS; |
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} |
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} |
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static DEVICE_ATTR(delete, S_IWUSR, NULL, store_srp_rport_delete); |
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static ssize_t show_srp_rport_state(struct device *dev, |
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struct device_attribute *attr, |
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char *buf) |
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{ |
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static const char *const state_name[] = { |
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[SRP_RPORT_RUNNING] = "running", |
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[SRP_RPORT_BLOCKED] = "blocked", |
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[SRP_RPORT_FAIL_FAST] = "fail-fast", |
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[SRP_RPORT_LOST] = "lost", |
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}; |
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struct srp_rport *rport = transport_class_to_srp_rport(dev); |
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enum srp_rport_state state = rport->state; |
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return sprintf(buf, "%s\n", |
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(unsigned)state < ARRAY_SIZE(state_name) ? |
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state_name[state] : "???"); |
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} |
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static DEVICE_ATTR(state, S_IRUGO, show_srp_rport_state, NULL); |
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static ssize_t srp_show_tmo(char *buf, int tmo) |
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{ |
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return tmo >= 0 ? sprintf(buf, "%d\n", tmo) : sprintf(buf, "off\n"); |
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} |
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int srp_parse_tmo(int *tmo, const char *buf) |
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{ |
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int res = 0; |
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if (strncmp(buf, "off", 3) != 0) |
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res = kstrtoint(buf, 0, tmo); |
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else |
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*tmo = -1; |
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return res; |
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} |
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EXPORT_SYMBOL(srp_parse_tmo); |
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static ssize_t show_reconnect_delay(struct device *dev, |
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struct device_attribute *attr, char *buf) |
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{ |
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struct srp_rport *rport = transport_class_to_srp_rport(dev); |
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return srp_show_tmo(buf, rport->reconnect_delay); |
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} |
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static ssize_t store_reconnect_delay(struct device *dev, |
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struct device_attribute *attr, |
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const char *buf, const size_t count) |
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{ |
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struct srp_rport *rport = transport_class_to_srp_rport(dev); |
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int res, delay; |
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res = srp_parse_tmo(&delay, buf); |
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if (res) |
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goto out; |
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res = srp_tmo_valid(delay, rport->fast_io_fail_tmo, |
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rport->dev_loss_tmo); |
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if (res) |
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goto out; |
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if (rport->reconnect_delay <= 0 && delay > 0 && |
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rport->state != SRP_RPORT_RUNNING) { |
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queue_delayed_work(system_long_wq, &rport->reconnect_work, |
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delay * HZ); |
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} else if (delay <= 0) { |
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cancel_delayed_work(&rport->reconnect_work); |
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} |
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rport->reconnect_delay = delay; |
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res = count; |
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out: |
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return res; |
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} |
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static DEVICE_ATTR(reconnect_delay, S_IRUGO | S_IWUSR, show_reconnect_delay, |
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store_reconnect_delay); |
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static ssize_t show_failed_reconnects(struct device *dev, |
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struct device_attribute *attr, char *buf) |
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{ |
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struct srp_rport *rport = transport_class_to_srp_rport(dev); |
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return sprintf(buf, "%d\n", rport->failed_reconnects); |
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} |
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static DEVICE_ATTR(failed_reconnects, S_IRUGO, show_failed_reconnects, NULL); |
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static ssize_t show_srp_rport_fast_io_fail_tmo(struct device *dev, |
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struct device_attribute *attr, |
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char *buf) |
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{ |
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struct srp_rport *rport = transport_class_to_srp_rport(dev); |
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return srp_show_tmo(buf, rport->fast_io_fail_tmo); |
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} |
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static ssize_t store_srp_rport_fast_io_fail_tmo(struct device *dev, |
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struct device_attribute *attr, |
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const char *buf, size_t count) |
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{ |
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struct srp_rport *rport = transport_class_to_srp_rport(dev); |
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int res; |
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int fast_io_fail_tmo; |
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res = srp_parse_tmo(&fast_io_fail_tmo, buf); |
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if (res) |
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goto out; |
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res = srp_tmo_valid(rport->reconnect_delay, fast_io_fail_tmo, |
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rport->dev_loss_tmo); |
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if (res) |
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goto out; |
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rport->fast_io_fail_tmo = fast_io_fail_tmo; |
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res = count; |
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out: |
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return res; |
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} |
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static DEVICE_ATTR(fast_io_fail_tmo, S_IRUGO | S_IWUSR, |
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show_srp_rport_fast_io_fail_tmo, |
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store_srp_rport_fast_io_fail_tmo); |
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static ssize_t show_srp_rport_dev_loss_tmo(struct device *dev, |
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struct device_attribute *attr, |
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char *buf) |
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{ |
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struct srp_rport *rport = transport_class_to_srp_rport(dev); |
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return srp_show_tmo(buf, rport->dev_loss_tmo); |
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} |
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static ssize_t store_srp_rport_dev_loss_tmo(struct device *dev, |
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struct device_attribute *attr, |
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const char *buf, size_t count) |
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{ |
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struct srp_rport *rport = transport_class_to_srp_rport(dev); |
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int res; |
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int dev_loss_tmo; |
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res = srp_parse_tmo(&dev_loss_tmo, buf); |
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if (res) |
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goto out; |
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res = srp_tmo_valid(rport->reconnect_delay, rport->fast_io_fail_tmo, |
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dev_loss_tmo); |
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if (res) |
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goto out; |
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rport->dev_loss_tmo = dev_loss_tmo; |
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res = count; |
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out: |
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return res; |
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} |
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static DEVICE_ATTR(dev_loss_tmo, S_IRUGO | S_IWUSR, |
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show_srp_rport_dev_loss_tmo, |
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store_srp_rport_dev_loss_tmo); |
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static int srp_rport_set_state(struct srp_rport *rport, |
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enum srp_rport_state new_state) |
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{ |
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enum srp_rport_state old_state = rport->state; |
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lockdep_assert_held(&rport->mutex); |
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switch (new_state) { |
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case SRP_RPORT_RUNNING: |
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switch (old_state) { |
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case SRP_RPORT_LOST: |
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goto invalid; |
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default: |
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break; |
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} |
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break; |
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case SRP_RPORT_BLOCKED: |
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switch (old_state) { |
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case SRP_RPORT_RUNNING: |
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break; |
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default: |
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goto invalid; |
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} |
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break; |
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case SRP_RPORT_FAIL_FAST: |
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switch (old_state) { |
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case SRP_RPORT_LOST: |
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goto invalid; |
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default: |
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break; |
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} |
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break; |
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case SRP_RPORT_LOST: |
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break; |
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} |
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rport->state = new_state; |
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return 0; |
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invalid: |
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return -EINVAL; |
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} |
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/** |
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* srp_reconnect_work() - reconnect and schedule a new attempt if necessary |
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* @work: Work structure used for scheduling this operation. |
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*/ |
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static void srp_reconnect_work(struct work_struct *work) |
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{ |
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struct srp_rport *rport = container_of(to_delayed_work(work), |
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struct srp_rport, reconnect_work); |
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struct Scsi_Host *shost = rport_to_shost(rport); |
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int delay, res; |
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res = srp_reconnect_rport(rport); |
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if (res != 0) { |
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shost_printk(KERN_ERR, shost, |
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"reconnect attempt %d failed (%d)\n", |
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++rport->failed_reconnects, res); |
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delay = rport->reconnect_delay * |
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min(100, max(1, rport->failed_reconnects - 10)); |
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if (delay > 0) |
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queue_delayed_work(system_long_wq, |
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&rport->reconnect_work, delay * HZ); |
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} |
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} |
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/* |
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* scsi_target_block() must have been called before this function is |
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* called to guarantee that no .queuecommand() calls are in progress. |
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*/ |
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static void __rport_fail_io_fast(struct srp_rport *rport) |
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{ |
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struct Scsi_Host *shost = rport_to_shost(rport); |
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struct srp_internal *i; |
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lockdep_assert_held(&rport->mutex); |
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if (srp_rport_set_state(rport, SRP_RPORT_FAIL_FAST)) |
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return; |
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scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE); |
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/* Involve the LLD if possible to terminate all I/O on the rport. */ |
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i = to_srp_internal(shost->transportt); |
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if (i->f->terminate_rport_io) |
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i->f->terminate_rport_io(rport); |
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} |
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/** |
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* rport_fast_io_fail_timedout() - fast I/O failure timeout handler |
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* @work: Work structure used for scheduling this operation. |
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*/ |
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static void rport_fast_io_fail_timedout(struct work_struct *work) |
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{ |
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struct srp_rport *rport = container_of(to_delayed_work(work), |
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struct srp_rport, fast_io_fail_work); |
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struct Scsi_Host *shost = rport_to_shost(rport); |
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pr_info("fast_io_fail_tmo expired for SRP %s / %s.\n", |
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dev_name(&rport->dev), dev_name(&shost->shost_gendev)); |
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mutex_lock(&rport->mutex); |
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if (rport->state == SRP_RPORT_BLOCKED) |
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__rport_fail_io_fast(rport); |
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mutex_unlock(&rport->mutex); |
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} |
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/** |
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* rport_dev_loss_timedout() - device loss timeout handler |
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* @work: Work structure used for scheduling this operation. |
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*/ |
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static void rport_dev_loss_timedout(struct work_struct *work) |
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{ |
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struct srp_rport *rport = container_of(to_delayed_work(work), |
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struct srp_rport, dev_loss_work); |
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struct Scsi_Host *shost = rport_to_shost(rport); |
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struct srp_internal *i = to_srp_internal(shost->transportt); |
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pr_info("dev_loss_tmo expired for SRP %s / %s.\n", |
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dev_name(&rport->dev), dev_name(&shost->shost_gendev)); |
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mutex_lock(&rport->mutex); |
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WARN_ON(srp_rport_set_state(rport, SRP_RPORT_LOST) != 0); |
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scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE); |
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mutex_unlock(&rport->mutex); |
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i->f->rport_delete(rport); |
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} |
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static void __srp_start_tl_fail_timers(struct srp_rport *rport) |
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{ |
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struct Scsi_Host *shost = rport_to_shost(rport); |
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int delay, fast_io_fail_tmo, dev_loss_tmo; |
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lockdep_assert_held(&rport->mutex); |
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delay = rport->reconnect_delay; |
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fast_io_fail_tmo = rport->fast_io_fail_tmo; |
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dev_loss_tmo = rport->dev_loss_tmo; |
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pr_debug("%s current state: %d\n", dev_name(&shost->shost_gendev), |
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rport->state); |
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if (rport->state == SRP_RPORT_LOST) |
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return; |
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if (delay > 0) |
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queue_delayed_work(system_long_wq, &rport->reconnect_work, |
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1UL * delay * HZ); |
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if ((fast_io_fail_tmo >= 0 || dev_loss_tmo >= 0) && |
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srp_rport_set_state(rport, SRP_RPORT_BLOCKED) == 0) { |
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pr_debug("%s new state: %d\n", dev_name(&shost->shost_gendev), |
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rport->state); |
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scsi_target_block(&shost->shost_gendev); |
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if (fast_io_fail_tmo >= 0) |
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queue_delayed_work(system_long_wq, |
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&rport->fast_io_fail_work, |
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1UL * fast_io_fail_tmo * HZ); |
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if (dev_loss_tmo >= 0) |
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queue_delayed_work(system_long_wq, |
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&rport->dev_loss_work, |
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1UL * dev_loss_tmo * HZ); |
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} |
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} |
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|
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/** |
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* srp_start_tl_fail_timers() - start the transport layer failure timers |
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* @rport: SRP target port. |
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* |
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* Start the transport layer fast I/O failure and device loss timers. Do not |
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* modify a timer that was already started. |
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*/ |
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void srp_start_tl_fail_timers(struct srp_rport *rport) |
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{ |
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mutex_lock(&rport->mutex); |
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__srp_start_tl_fail_timers(rport); |
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mutex_unlock(&rport->mutex); |
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} |
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EXPORT_SYMBOL(srp_start_tl_fail_timers); |
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|
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/** |
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* srp_reconnect_rport() - reconnect to an SRP target port |
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* @rport: SRP target port. |
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* |
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* Blocks SCSI command queueing before invoking reconnect() such that |
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* queuecommand() won't be invoked concurrently with reconnect() from outside |
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* the SCSI EH. This is important since a reconnect() implementation may |
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* reallocate resources needed by queuecommand(). |
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* |
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* Notes: |
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* - This function neither waits until outstanding requests have finished nor |
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* tries to abort these. It is the responsibility of the reconnect() |
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* function to finish outstanding commands before reconnecting to the target |
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* port. |
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* - 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); |
|
__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);
|
|
|