diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/s390/scsi/zfcp_erp.c | 1866 |
1 files changed, 1866 insertions, 0 deletions
diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c new file mode 100644 index 000000000..78d52a4c5 --- /dev/null +++ b/drivers/s390/scsi/zfcp_erp.c @@ -0,0 +1,1866 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * zfcp device driver + * + * Error Recovery Procedures (ERP). + * + * Copyright IBM Corp. 2002, 2020 + */ + +#define KMSG_COMPONENT "zfcp" +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + +#include <linux/kthread.h> +#include <linux/bug.h> +#include "zfcp_ext.h" +#include "zfcp_reqlist.h" +#include "zfcp_diag.h" + +#define ZFCP_MAX_ERPS 3 + +enum zfcp_erp_act_flags { + ZFCP_STATUS_ERP_TIMEDOUT = 0x10000000, + ZFCP_STATUS_ERP_CLOSE_ONLY = 0x01000000, + ZFCP_STATUS_ERP_DISMISSED = 0x00200000, + ZFCP_STATUS_ERP_LOWMEM = 0x00400000, + ZFCP_STATUS_ERP_NO_REF = 0x00800000, +}; + +/* + * Eyecatcher pseudo flag to bitwise or-combine with enum zfcp_erp_act_type. + * Used to indicate that an ERP action could not be set up despite a detected + * need for some recovery. + */ +#define ZFCP_ERP_ACTION_NONE 0xc0 +/* + * Eyecatcher pseudo flag to bitwise or-combine with enum zfcp_erp_act_type. + * Used to indicate that ERP not needed because the object has + * ZFCP_STATUS_COMMON_ERP_FAILED. + */ +#define ZFCP_ERP_ACTION_FAILED 0xe0 + +enum zfcp_erp_act_result { + ZFCP_ERP_SUCCEEDED = 0, + ZFCP_ERP_FAILED = 1, + ZFCP_ERP_CONTINUES = 2, + ZFCP_ERP_EXIT = 3, + ZFCP_ERP_DISMISSED = 4, + ZFCP_ERP_NOMEM = 5, +}; + +static void zfcp_erp_adapter_block(struct zfcp_adapter *adapter, int mask) +{ + zfcp_erp_clear_adapter_status(adapter, + ZFCP_STATUS_COMMON_UNBLOCKED | mask); +} + +static bool zfcp_erp_action_is_running(struct zfcp_erp_action *act) +{ + struct zfcp_erp_action *curr_act; + + list_for_each_entry(curr_act, &act->adapter->erp_running_head, list) + if (act == curr_act) + return true; + return false; +} + +static void zfcp_erp_action_ready(struct zfcp_erp_action *act) +{ + struct zfcp_adapter *adapter = act->adapter; + + list_move(&act->list, &adapter->erp_ready_head); + zfcp_dbf_rec_run("erardy1", act); + wake_up(&adapter->erp_ready_wq); + zfcp_dbf_rec_run("erardy2", act); +} + +static void zfcp_erp_action_dismiss(struct zfcp_erp_action *act) +{ + act->status |= ZFCP_STATUS_ERP_DISMISSED; + if (zfcp_erp_action_is_running(act)) + zfcp_erp_action_ready(act); +} + +static void zfcp_erp_action_dismiss_lun(struct scsi_device *sdev) +{ + struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev); + + if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_ERP_INUSE) + zfcp_erp_action_dismiss(&zfcp_sdev->erp_action); +} + +static void zfcp_erp_action_dismiss_port(struct zfcp_port *port) +{ + struct scsi_device *sdev; + + if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_INUSE) + zfcp_erp_action_dismiss(&port->erp_action); + else { + spin_lock(port->adapter->scsi_host->host_lock); + __shost_for_each_device(sdev, port->adapter->scsi_host) + if (sdev_to_zfcp(sdev)->port == port) + zfcp_erp_action_dismiss_lun(sdev); + spin_unlock(port->adapter->scsi_host->host_lock); + } +} + +static void zfcp_erp_action_dismiss_adapter(struct zfcp_adapter *adapter) +{ + struct zfcp_port *port; + + if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_INUSE) + zfcp_erp_action_dismiss(&adapter->erp_action); + else { + read_lock(&adapter->port_list_lock); + list_for_each_entry(port, &adapter->port_list, list) + zfcp_erp_action_dismiss_port(port); + read_unlock(&adapter->port_list_lock); + } +} + +static enum zfcp_erp_act_type zfcp_erp_handle_failed( + enum zfcp_erp_act_type want, struct zfcp_adapter *adapter, + struct zfcp_port *port, struct scsi_device *sdev) +{ + enum zfcp_erp_act_type need = want; + struct zfcp_scsi_dev *zsdev; + + switch (want) { + case ZFCP_ERP_ACTION_REOPEN_LUN: + zsdev = sdev_to_zfcp(sdev); + if (atomic_read(&zsdev->status) & ZFCP_STATUS_COMMON_ERP_FAILED) + need = 0; + break; + case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED: + if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED) + need = 0; + break; + case ZFCP_ERP_ACTION_REOPEN_PORT: + if (atomic_read(&port->status) & + ZFCP_STATUS_COMMON_ERP_FAILED) { + need = 0; + /* ensure propagation of failed status to new devices */ + zfcp_erp_set_port_status( + port, ZFCP_STATUS_COMMON_ERP_FAILED); + } + break; + case ZFCP_ERP_ACTION_REOPEN_ADAPTER: + if (atomic_read(&adapter->status) & + ZFCP_STATUS_COMMON_ERP_FAILED) { + need = 0; + /* ensure propagation of failed status to new devices */ + zfcp_erp_set_adapter_status( + adapter, ZFCP_STATUS_COMMON_ERP_FAILED); + } + break; + } + + return need; +} + +static enum zfcp_erp_act_type zfcp_erp_required_act(enum zfcp_erp_act_type want, + struct zfcp_adapter *adapter, + struct zfcp_port *port, + struct scsi_device *sdev) +{ + enum zfcp_erp_act_type need = want; + int l_status, p_status, a_status; + struct zfcp_scsi_dev *zfcp_sdev; + + switch (want) { + case ZFCP_ERP_ACTION_REOPEN_LUN: + zfcp_sdev = sdev_to_zfcp(sdev); + l_status = atomic_read(&zfcp_sdev->status); + if (l_status & ZFCP_STATUS_COMMON_ERP_INUSE) + return 0; + p_status = atomic_read(&port->status); + if (!(p_status & ZFCP_STATUS_COMMON_RUNNING) || + p_status & ZFCP_STATUS_COMMON_ERP_FAILED) + return 0; + if (!(p_status & ZFCP_STATUS_COMMON_UNBLOCKED)) + need = ZFCP_ERP_ACTION_REOPEN_PORT; + fallthrough; + case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED: + p_status = atomic_read(&port->status); + if (!(p_status & ZFCP_STATUS_COMMON_OPEN)) + need = ZFCP_ERP_ACTION_REOPEN_PORT; + fallthrough; + case ZFCP_ERP_ACTION_REOPEN_PORT: + p_status = atomic_read(&port->status); + if (p_status & ZFCP_STATUS_COMMON_ERP_INUSE) + return 0; + a_status = atomic_read(&adapter->status); + if (!(a_status & ZFCP_STATUS_COMMON_RUNNING) || + a_status & ZFCP_STATUS_COMMON_ERP_FAILED) + return 0; + if (p_status & ZFCP_STATUS_COMMON_NOESC) + return need; + if (!(a_status & ZFCP_STATUS_COMMON_UNBLOCKED)) + need = ZFCP_ERP_ACTION_REOPEN_ADAPTER; + fallthrough; + case ZFCP_ERP_ACTION_REOPEN_ADAPTER: + a_status = atomic_read(&adapter->status); + if (a_status & ZFCP_STATUS_COMMON_ERP_INUSE) + return 0; + if (!(a_status & ZFCP_STATUS_COMMON_RUNNING) && + !(a_status & ZFCP_STATUS_COMMON_OPEN)) + return 0; /* shutdown requested for closed adapter */ + } + + return need; +} + +static struct zfcp_erp_action *zfcp_erp_setup_act(enum zfcp_erp_act_type need, + u32 act_status, + struct zfcp_adapter *adapter, + struct zfcp_port *port, + struct scsi_device *sdev) +{ + struct zfcp_erp_action *erp_action; + struct zfcp_scsi_dev *zfcp_sdev; + + if (WARN_ON_ONCE(need != ZFCP_ERP_ACTION_REOPEN_LUN && + need != ZFCP_ERP_ACTION_REOPEN_PORT && + need != ZFCP_ERP_ACTION_REOPEN_PORT_FORCED && + need != ZFCP_ERP_ACTION_REOPEN_ADAPTER)) + return NULL; + + switch (need) { + case ZFCP_ERP_ACTION_REOPEN_LUN: + zfcp_sdev = sdev_to_zfcp(sdev); + if (!(act_status & ZFCP_STATUS_ERP_NO_REF)) + if (scsi_device_get(sdev)) + return NULL; + atomic_or(ZFCP_STATUS_COMMON_ERP_INUSE, + &zfcp_sdev->status); + erp_action = &zfcp_sdev->erp_action; + WARN_ON_ONCE(erp_action->port != port); + WARN_ON_ONCE(erp_action->sdev != sdev); + if (!(atomic_read(&zfcp_sdev->status) & + ZFCP_STATUS_COMMON_RUNNING)) + act_status |= ZFCP_STATUS_ERP_CLOSE_ONLY; + break; + + case ZFCP_ERP_ACTION_REOPEN_PORT: + case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED: + if (!get_device(&port->dev)) + return NULL; + zfcp_erp_action_dismiss_port(port); + atomic_or(ZFCP_STATUS_COMMON_ERP_INUSE, &port->status); + erp_action = &port->erp_action; + WARN_ON_ONCE(erp_action->port != port); + WARN_ON_ONCE(erp_action->sdev != NULL); + if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_RUNNING)) + act_status |= ZFCP_STATUS_ERP_CLOSE_ONLY; + break; + + case ZFCP_ERP_ACTION_REOPEN_ADAPTER: + kref_get(&adapter->ref); + zfcp_erp_action_dismiss_adapter(adapter); + atomic_or(ZFCP_STATUS_COMMON_ERP_INUSE, &adapter->status); + erp_action = &adapter->erp_action; + WARN_ON_ONCE(erp_action->port != NULL); + WARN_ON_ONCE(erp_action->sdev != NULL); + if (!(atomic_read(&adapter->status) & + ZFCP_STATUS_COMMON_RUNNING)) + act_status |= ZFCP_STATUS_ERP_CLOSE_ONLY; + break; + } + + WARN_ON_ONCE(erp_action->adapter != adapter); + memset(&erp_action->list, 0, sizeof(erp_action->list)); + memset(&erp_action->timer, 0, sizeof(erp_action->timer)); + erp_action->step = ZFCP_ERP_STEP_UNINITIALIZED; + erp_action->fsf_req_id = 0; + erp_action->type = need; + erp_action->status = act_status; + + return erp_action; +} + +static void zfcp_erp_action_enqueue(enum zfcp_erp_act_type want, + struct zfcp_adapter *adapter, + struct zfcp_port *port, + struct scsi_device *sdev, + char *dbftag, u32 act_status) +{ + enum zfcp_erp_act_type need; + struct zfcp_erp_action *act; + + need = zfcp_erp_handle_failed(want, adapter, port, sdev); + if (!need) { + need = ZFCP_ERP_ACTION_FAILED; /* marker for trace */ + goto out; + } + + if (!adapter->erp_thread) { + need = ZFCP_ERP_ACTION_NONE; /* marker for trace */ + goto out; + } + + need = zfcp_erp_required_act(want, adapter, port, sdev); + if (!need) + goto out; + + act = zfcp_erp_setup_act(need, act_status, adapter, port, sdev); + if (!act) { + need |= ZFCP_ERP_ACTION_NONE; /* marker for trace */ + goto out; + } + atomic_or(ZFCP_STATUS_ADAPTER_ERP_PENDING, &adapter->status); + ++adapter->erp_total_count; + list_add_tail(&act->list, &adapter->erp_ready_head); + wake_up(&adapter->erp_ready_wq); + out: + zfcp_dbf_rec_trig(dbftag, adapter, port, sdev, want, need); +} + +void zfcp_erp_port_forced_no_port_dbf(char *dbftag, + struct zfcp_adapter *adapter, + u64 port_name, u32 port_id) +{ + unsigned long flags; + static /* don't waste stack */ struct zfcp_port tmpport; + + write_lock_irqsave(&adapter->erp_lock, flags); + /* Stand-in zfcp port with fields just good enough for + * zfcp_dbf_rec_trig() and zfcp_dbf_set_common(). + * Under lock because tmpport is static. + */ + atomic_set(&tmpport.status, -1); /* unknown */ + tmpport.wwpn = port_name; + tmpport.d_id = port_id; + zfcp_dbf_rec_trig(dbftag, adapter, &tmpport, NULL, + ZFCP_ERP_ACTION_REOPEN_PORT_FORCED, + ZFCP_ERP_ACTION_NONE); + write_unlock_irqrestore(&adapter->erp_lock, flags); +} + +static void _zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter, + int clear_mask, char *dbftag) +{ + zfcp_erp_adapter_block(adapter, clear_mask); + zfcp_scsi_schedule_rports_block(adapter); + + zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER, + adapter, NULL, NULL, dbftag, 0); +} + +/** + * zfcp_erp_adapter_reopen - Reopen adapter. + * @adapter: Adapter to reopen. + * @clear: Status flags to clear. + * @dbftag: Tag for debug trace event. + */ +void zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter, int clear, + char *dbftag) +{ + unsigned long flags; + + zfcp_erp_adapter_block(adapter, clear); + zfcp_scsi_schedule_rports_block(adapter); + + write_lock_irqsave(&adapter->erp_lock, flags); + zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER, adapter, + NULL, NULL, dbftag, 0); + write_unlock_irqrestore(&adapter->erp_lock, flags); +} + +/** + * zfcp_erp_adapter_shutdown - Shutdown adapter. + * @adapter: Adapter to shut down. + * @clear: Status flags to clear. + * @dbftag: Tag for debug trace event. + */ +void zfcp_erp_adapter_shutdown(struct zfcp_adapter *adapter, int clear, + char *dbftag) +{ + int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED; + zfcp_erp_adapter_reopen(adapter, clear | flags, dbftag); +} + +/** + * zfcp_erp_port_shutdown - Shutdown port + * @port: Port to shut down. + * @clear: Status flags to clear. + * @dbftag: Tag for debug trace event. + */ +void zfcp_erp_port_shutdown(struct zfcp_port *port, int clear, char *dbftag) +{ + int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED; + zfcp_erp_port_reopen(port, clear | flags, dbftag); +} + +static void zfcp_erp_port_block(struct zfcp_port *port, int clear) +{ + zfcp_erp_clear_port_status(port, + ZFCP_STATUS_COMMON_UNBLOCKED | clear); +} + +static void _zfcp_erp_port_forced_reopen(struct zfcp_port *port, int clear, + char *dbftag) +{ + zfcp_erp_port_block(port, clear); + zfcp_scsi_schedule_rport_block(port); + + zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_PORT_FORCED, + port->adapter, port, NULL, dbftag, 0); +} + +/** + * zfcp_erp_port_forced_reopen - Forced close of port and open again + * @port: Port to force close and to reopen. + * @clear: Status flags to clear. + * @dbftag: Tag for debug trace event. + */ +void zfcp_erp_port_forced_reopen(struct zfcp_port *port, int clear, + char *dbftag) +{ + unsigned long flags; + struct zfcp_adapter *adapter = port->adapter; + + write_lock_irqsave(&adapter->erp_lock, flags); + _zfcp_erp_port_forced_reopen(port, clear, dbftag); + write_unlock_irqrestore(&adapter->erp_lock, flags); +} + +static void _zfcp_erp_port_reopen(struct zfcp_port *port, int clear, + char *dbftag) +{ + zfcp_erp_port_block(port, clear); + zfcp_scsi_schedule_rport_block(port); + + zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_PORT, + port->adapter, port, NULL, dbftag, 0); +} + +/** + * zfcp_erp_port_reopen - trigger remote port recovery + * @port: port to recover + * @clear: flags in port status to be cleared + * @dbftag: Tag for debug trace event. + */ +void zfcp_erp_port_reopen(struct zfcp_port *port, int clear, char *dbftag) +{ + unsigned long flags; + struct zfcp_adapter *adapter = port->adapter; + + write_lock_irqsave(&adapter->erp_lock, flags); + _zfcp_erp_port_reopen(port, clear, dbftag); + write_unlock_irqrestore(&adapter->erp_lock, flags); +} + +static void zfcp_erp_lun_block(struct scsi_device *sdev, int clear_mask) +{ + zfcp_erp_clear_lun_status(sdev, + ZFCP_STATUS_COMMON_UNBLOCKED | clear_mask); +} + +static void _zfcp_erp_lun_reopen(struct scsi_device *sdev, int clear, + char *dbftag, u32 act_status) +{ + struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev); + struct zfcp_adapter *adapter = zfcp_sdev->port->adapter; + + zfcp_erp_lun_block(sdev, clear); + + zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_LUN, adapter, + zfcp_sdev->port, sdev, dbftag, act_status); +} + +/** + * zfcp_erp_lun_reopen - initiate reopen of a LUN + * @sdev: SCSI device / LUN to be reopened + * @clear: specifies flags in LUN status to be cleared + * @dbftag: Tag for debug trace event. + * + * Return: 0 on success, < 0 on error + */ +void zfcp_erp_lun_reopen(struct scsi_device *sdev, int clear, char *dbftag) +{ + unsigned long flags; + struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev); + struct zfcp_port *port = zfcp_sdev->port; + struct zfcp_adapter *adapter = port->adapter; + + write_lock_irqsave(&adapter->erp_lock, flags); + _zfcp_erp_lun_reopen(sdev, clear, dbftag, 0); + write_unlock_irqrestore(&adapter->erp_lock, flags); +} + +/** + * zfcp_erp_lun_shutdown - Shutdown LUN + * @sdev: SCSI device / LUN to shut down. + * @clear: Status flags to clear. + * @dbftag: Tag for debug trace event. + */ +void zfcp_erp_lun_shutdown(struct scsi_device *sdev, int clear, char *dbftag) +{ + int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED; + zfcp_erp_lun_reopen(sdev, clear | flags, dbftag); +} + +/** + * zfcp_erp_lun_shutdown_wait - Shutdown LUN and wait for erp completion + * @sdev: SCSI device / LUN to shut down. + * @dbftag: Tag for debug trace event. + * + * Do not acquire a reference for the LUN when creating the ERP + * action. It is safe, because this function waits for the ERP to + * complete first. This allows to shutdown the LUN, even when the SCSI + * device is in the state SDEV_DEL when scsi_device_get will fail. + */ +void zfcp_erp_lun_shutdown_wait(struct scsi_device *sdev, char *dbftag) +{ + unsigned long flags; + struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev); + struct zfcp_port *port = zfcp_sdev->port; + struct zfcp_adapter *adapter = port->adapter; + int clear = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED; + + write_lock_irqsave(&adapter->erp_lock, flags); + _zfcp_erp_lun_reopen(sdev, clear, dbftag, ZFCP_STATUS_ERP_NO_REF); + write_unlock_irqrestore(&adapter->erp_lock, flags); + + zfcp_erp_wait(adapter); +} + +static int zfcp_erp_status_change_set(unsigned long mask, atomic_t *status) +{ + return (atomic_read(status) ^ mask) & mask; +} + +static void zfcp_erp_adapter_unblock(struct zfcp_adapter *adapter) +{ + if (zfcp_erp_status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED, + &adapter->status)) + zfcp_dbf_rec_run("eraubl1", &adapter->erp_action); + atomic_or(ZFCP_STATUS_COMMON_UNBLOCKED, &adapter->status); +} + +static void zfcp_erp_port_unblock(struct zfcp_port *port) +{ + if (zfcp_erp_status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED, + &port->status)) + zfcp_dbf_rec_run("erpubl1", &port->erp_action); + atomic_or(ZFCP_STATUS_COMMON_UNBLOCKED, &port->status); +} + +static void zfcp_erp_lun_unblock(struct scsi_device *sdev) +{ + struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev); + + if (zfcp_erp_status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED, + &zfcp_sdev->status)) + zfcp_dbf_rec_run("erlubl1", &sdev_to_zfcp(sdev)->erp_action); + atomic_or(ZFCP_STATUS_COMMON_UNBLOCKED, &zfcp_sdev->status); +} + +static void zfcp_erp_action_to_running(struct zfcp_erp_action *erp_action) +{ + list_move(&erp_action->list, &erp_action->adapter->erp_running_head); + zfcp_dbf_rec_run("erator1", erp_action); +} + +static void zfcp_erp_strategy_check_fsfreq(struct zfcp_erp_action *act) +{ + struct zfcp_adapter *adapter = act->adapter; + struct zfcp_fsf_req *req; + + if (!act->fsf_req_id) + return; + + spin_lock(&adapter->req_list->lock); + req = _zfcp_reqlist_find(adapter->req_list, act->fsf_req_id); + if (req && req->erp_action == act) { + if (act->status & (ZFCP_STATUS_ERP_DISMISSED | + ZFCP_STATUS_ERP_TIMEDOUT)) { + req->status |= ZFCP_STATUS_FSFREQ_DISMISSED; + zfcp_dbf_rec_run("erscf_1", act); + /* lock-free concurrent access with + * zfcp_erp_timeout_handler() + */ + WRITE_ONCE(req->erp_action, NULL); + } + if (act->status & ZFCP_STATUS_ERP_TIMEDOUT) + zfcp_dbf_rec_run("erscf_2", act); + if (req->status & ZFCP_STATUS_FSFREQ_DISMISSED) + act->fsf_req_id = 0; + } else + act->fsf_req_id = 0; + spin_unlock(&adapter->req_list->lock); +} + +/** + * zfcp_erp_notify - Trigger ERP action. + * @erp_action: ERP action to continue. + * @set_mask: ERP action status flags to set. + */ +void zfcp_erp_notify(struct zfcp_erp_action *erp_action, unsigned long set_mask) +{ + struct zfcp_adapter *adapter = erp_action->adapter; + unsigned long flags; + + write_lock_irqsave(&adapter->erp_lock, flags); + if (zfcp_erp_action_is_running(erp_action)) { + erp_action->status |= set_mask; + zfcp_erp_action_ready(erp_action); + } + write_unlock_irqrestore(&adapter->erp_lock, flags); +} + +/** + * zfcp_erp_timeout_handler - Trigger ERP action from timed out ERP request + * @t: timer list entry embedded in zfcp FSF request + */ +void zfcp_erp_timeout_handler(struct timer_list *t) +{ + struct zfcp_fsf_req *fsf_req = from_timer(fsf_req, t, timer); + struct zfcp_erp_action *act; + + if (fsf_req->status & ZFCP_STATUS_FSFREQ_DISMISSED) + return; + /* lock-free concurrent access with zfcp_erp_strategy_check_fsfreq() */ + act = READ_ONCE(fsf_req->erp_action); + if (!act) + return; + zfcp_erp_notify(act, ZFCP_STATUS_ERP_TIMEDOUT); +} + +static void zfcp_erp_memwait_handler(struct timer_list *t) +{ + struct zfcp_erp_action *act = from_timer(act, t, timer); + + zfcp_erp_notify(act, 0); +} + +static void zfcp_erp_strategy_memwait(struct zfcp_erp_action *erp_action) +{ + timer_setup(&erp_action->timer, zfcp_erp_memwait_handler, 0); + erp_action->timer.expires = jiffies + HZ; + add_timer(&erp_action->timer); +} + +void zfcp_erp_port_forced_reopen_all(struct zfcp_adapter *adapter, + int clear, char *dbftag) +{ + unsigned long flags; + struct zfcp_port *port; + + write_lock_irqsave(&adapter->erp_lock, flags); + read_lock(&adapter->port_list_lock); + list_for_each_entry(port, &adapter->port_list, list) + _zfcp_erp_port_forced_reopen(port, clear, dbftag); + read_unlock(&adapter->port_list_lock); + write_unlock_irqrestore(&adapter->erp_lock, flags); +} + +static void _zfcp_erp_port_reopen_all(struct zfcp_adapter *adapter, + int clear, char *dbftag) +{ + struct zfcp_port *port; + + read_lock(&adapter->port_list_lock); + list_for_each_entry(port, &adapter->port_list, list) + _zfcp_erp_port_reopen(port, clear, dbftag); + read_unlock(&adapter->port_list_lock); +} + +static void _zfcp_erp_lun_reopen_all(struct zfcp_port *port, int clear, + char *dbftag) +{ + struct scsi_device *sdev; + + spin_lock(port->adapter->scsi_host->host_lock); + __shost_for_each_device(sdev, port->adapter->scsi_host) + if (sdev_to_zfcp(sdev)->port == port) + _zfcp_erp_lun_reopen(sdev, clear, dbftag, 0); + spin_unlock(port->adapter->scsi_host->host_lock); +} + +static void zfcp_erp_strategy_followup_failed(struct zfcp_erp_action *act) +{ + switch (act->type) { + case ZFCP_ERP_ACTION_REOPEN_ADAPTER: + _zfcp_erp_adapter_reopen(act->adapter, 0, "ersff_1"); + break; + case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED: + _zfcp_erp_port_forced_reopen(act->port, 0, "ersff_2"); + break; + case ZFCP_ERP_ACTION_REOPEN_PORT: + _zfcp_erp_port_reopen(act->port, 0, "ersff_3"); + break; + case ZFCP_ERP_ACTION_REOPEN_LUN: + _zfcp_erp_lun_reopen(act->sdev, 0, "ersff_4", 0); + break; + } +} + +static void zfcp_erp_strategy_followup_success(struct zfcp_erp_action *act) +{ + switch (act->type) { + case ZFCP_ERP_ACTION_REOPEN_ADAPTER: + _zfcp_erp_port_reopen_all(act->adapter, 0, "ersfs_1"); + break; + case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED: + _zfcp_erp_port_reopen(act->port, 0, "ersfs_2"); + break; + case ZFCP_ERP_ACTION_REOPEN_PORT: + _zfcp_erp_lun_reopen_all(act->port, 0, "ersfs_3"); + break; + case ZFCP_ERP_ACTION_REOPEN_LUN: + /* NOP */ + break; + } +} + +static void zfcp_erp_wakeup(struct zfcp_adapter *adapter) +{ + unsigned long flags; + + read_lock_irqsave(&adapter->erp_lock, flags); + if (list_empty(&adapter->erp_ready_head) && + list_empty(&adapter->erp_running_head)) { + atomic_andnot(ZFCP_STATUS_ADAPTER_ERP_PENDING, + &adapter->status); + wake_up(&adapter->erp_done_wqh); + } + read_unlock_irqrestore(&adapter->erp_lock, flags); +} + +static void zfcp_erp_enqueue_ptp_port(struct zfcp_adapter *adapter) +{ + struct zfcp_port *port; + port = zfcp_port_enqueue(adapter, adapter->peer_wwpn, 0, + adapter->peer_d_id); + if (IS_ERR(port)) /* error or port already attached */ + return; + zfcp_erp_port_reopen(port, 0, "ereptp1"); +} + +static enum zfcp_erp_act_result zfcp_erp_adapter_strat_fsf_xconf( + struct zfcp_erp_action *erp_action) +{ + int retries; + int sleep = 1; + struct zfcp_adapter *adapter = erp_action->adapter; + + atomic_andnot(ZFCP_STATUS_ADAPTER_XCONFIG_OK, &adapter->status); + + for (retries = 7; retries; retries--) { + atomic_andnot(ZFCP_STATUS_ADAPTER_HOST_CON_INIT, + &adapter->status); + write_lock_irq(&adapter->erp_lock); + zfcp_erp_action_to_running(erp_action); + write_unlock_irq(&adapter->erp_lock); + if (zfcp_fsf_exchange_config_data(erp_action)) { + atomic_andnot(ZFCP_STATUS_ADAPTER_HOST_CON_INIT, + &adapter->status); + return ZFCP_ERP_FAILED; + } + + wait_event(adapter->erp_ready_wq, + !list_empty(&adapter->erp_ready_head)); + if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT) + break; + + if (!(atomic_read(&adapter->status) & + ZFCP_STATUS_ADAPTER_HOST_CON_INIT)) + break; + + ssleep(sleep); + sleep *= 2; + } + + atomic_andnot(ZFCP_STATUS_ADAPTER_HOST_CON_INIT, + &adapter->status); + + if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_XCONFIG_OK)) + return ZFCP_ERP_FAILED; + + return ZFCP_ERP_SUCCEEDED; +} + +static void +zfcp_erp_adapter_strategy_open_ptp_port(struct zfcp_adapter *const adapter) +{ + if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_PTP) + zfcp_erp_enqueue_ptp_port(adapter); +} + +static enum zfcp_erp_act_result zfcp_erp_adapter_strategy_open_fsf_xport( + struct zfcp_erp_action *act) +{ + int ret; + struct zfcp_adapter *adapter = act->adapter; + + write_lock_irq(&adapter->erp_lock); + zfcp_erp_action_to_running(act); + write_unlock_irq(&adapter->erp_lock); + + ret = zfcp_fsf_exchange_port_data(act); + if (ret == -EOPNOTSUPP) + return ZFCP_ERP_SUCCEEDED; + if (ret) + return ZFCP_ERP_FAILED; + + zfcp_dbf_rec_run("erasox1", act); + wait_event(adapter->erp_ready_wq, + !list_empty(&adapter->erp_ready_head)); + zfcp_dbf_rec_run("erasox2", act); + if (act->status & ZFCP_STATUS_ERP_TIMEDOUT) + return ZFCP_ERP_FAILED; + + return ZFCP_ERP_SUCCEEDED; +} + +static enum zfcp_erp_act_result +zfcp_erp_adapter_strategy_alloc_shost(struct zfcp_adapter *const adapter) +{ + struct zfcp_diag_adapter_config_data *const config_data = + &adapter->diagnostics->config_data; + struct zfcp_diag_adapter_port_data *const port_data = + &adapter->diagnostics->port_data; + unsigned long flags; + int rc; + + rc = zfcp_scsi_adapter_register(adapter); + if (rc == -EEXIST) + return ZFCP_ERP_SUCCEEDED; + else if (rc) + return ZFCP_ERP_FAILED; + + /* + * We allocated the shost for the first time. Before it was NULL, + * and so we deferred all updates in the xconf- and xport-data + * handlers. We need to make up for that now, and make all the updates + * that would have been done before. + * + * We can be sure that xconf- and xport-data succeeded, because + * otherwise this function is not called. But they might have been + * incomplete. + */ + + spin_lock_irqsave(&config_data->header.access_lock, flags); + zfcp_scsi_shost_update_config_data(adapter, &config_data->data, + !!config_data->header.incomplete); + spin_unlock_irqrestore(&config_data->header.access_lock, flags); + + if (adapter->adapter_features & FSF_FEATURE_HBAAPI_MANAGEMENT) { + spin_lock_irqsave(&port_data->header.access_lock, flags); + zfcp_scsi_shost_update_port_data(adapter, &port_data->data); + spin_unlock_irqrestore(&port_data->header.access_lock, flags); + } + + /* + * There is a remote possibility that the 'Exchange Port Data' request + * reports a different connectivity status than 'Exchange Config Data'. + * But any change to the connectivity status of the local optic that + * happens after the initial xconf request is expected to be reported + * to us, as soon as we post Status Read Buffers to the FCP channel + * firmware after this function. So any resulting inconsistency will + * only be momentary. + */ + if (config_data->header.incomplete) + zfcp_fsf_fc_host_link_down(adapter); + + return ZFCP_ERP_SUCCEEDED; +} + +static enum zfcp_erp_act_result zfcp_erp_adapter_strategy_open_fsf( + struct zfcp_erp_action *act) +{ + if (zfcp_erp_adapter_strat_fsf_xconf(act) == ZFCP_ERP_FAILED) + return ZFCP_ERP_FAILED; + + if (zfcp_erp_adapter_strategy_open_fsf_xport(act) == ZFCP_ERP_FAILED) + return ZFCP_ERP_FAILED; + + if (zfcp_erp_adapter_strategy_alloc_shost(act->adapter) == + ZFCP_ERP_FAILED) + return ZFCP_ERP_FAILED; + + zfcp_erp_adapter_strategy_open_ptp_port(act->adapter); + + if (mempool_resize(act->adapter->pool.sr_data, + act->adapter->stat_read_buf_num)) + return ZFCP_ERP_FAILED; + + if (mempool_resize(act->adapter->pool.status_read_req, + act->adapter->stat_read_buf_num)) + return ZFCP_ERP_FAILED; + + atomic_set(&act->adapter->stat_miss, act->adapter->stat_read_buf_num); + if (zfcp_status_read_refill(act->adapter)) + return ZFCP_ERP_FAILED; + + return ZFCP_ERP_SUCCEEDED; +} + +static void zfcp_erp_adapter_strategy_close(struct zfcp_erp_action *act) +{ + struct zfcp_adapter *adapter = act->adapter; + + /* close queues to ensure that buffers are not accessed by adapter */ + zfcp_qdio_close(adapter->qdio); + zfcp_fsf_req_dismiss_all(adapter); + adapter->fsf_req_seq_no = 0; + zfcp_fc_wka_ports_force_offline(adapter->gs); + /* all ports and LUNs are closed */ + zfcp_erp_clear_adapter_status(adapter, ZFCP_STATUS_COMMON_OPEN); + + atomic_andnot(ZFCP_STATUS_ADAPTER_XCONFIG_OK | + ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED, &adapter->status); +} + +static enum zfcp_erp_act_result zfcp_erp_adapter_strategy_open( + struct zfcp_erp_action *act) +{ + struct zfcp_adapter *adapter = act->adapter; + + if (zfcp_qdio_open(adapter->qdio)) { + atomic_andnot(ZFCP_STATUS_ADAPTER_XCONFIG_OK | + ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED, + &adapter->status); + return ZFCP_ERP_FAILED; + } + + if (zfcp_erp_adapter_strategy_open_fsf(act)) { + zfcp_erp_adapter_strategy_close(act); + return ZFCP_ERP_FAILED; + } + + atomic_or(ZFCP_STATUS_COMMON_OPEN, &adapter->status); + + return ZFCP_ERP_SUCCEEDED; +} + +static enum zfcp_erp_act_result zfcp_erp_adapter_strategy( + struct zfcp_erp_action *act) +{ + struct zfcp_adapter *adapter = act->adapter; + + if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN) { + zfcp_erp_adapter_strategy_close(act); + if (act->status & ZFCP_STATUS_ERP_CLOSE_ONLY) + return ZFCP_ERP_EXIT; + } + + if (zfcp_erp_adapter_strategy_open(act)) { + ssleep(8); + return ZFCP_ERP_FAILED; + } + + return ZFCP_ERP_SUCCEEDED; +} + +static enum zfcp_erp_act_result zfcp_erp_port_forced_strategy_close( + struct zfcp_erp_action *act) +{ + int retval; + + retval = zfcp_fsf_close_physical_port(act); + if (retval == -ENOMEM) + return ZFCP_ERP_NOMEM; + act->step = ZFCP_ERP_STEP_PHYS_PORT_CLOSING; + if (retval) + return ZFCP_ERP_FAILED; + + return ZFCP_ERP_CONTINUES; +} + +static enum zfcp_erp_act_result zfcp_erp_port_forced_strategy( + struct zfcp_erp_action *erp_action) +{ + struct zfcp_port *port = erp_action->port; + int status = atomic_read(&port->status); + + switch (erp_action->step) { + case ZFCP_ERP_STEP_UNINITIALIZED: + if ((status & ZFCP_STATUS_PORT_PHYS_OPEN) && + (status & ZFCP_STATUS_COMMON_OPEN)) + return zfcp_erp_port_forced_strategy_close(erp_action); + else + return ZFCP_ERP_FAILED; + + case ZFCP_ERP_STEP_PHYS_PORT_CLOSING: + if (!(status & ZFCP_STATUS_PORT_PHYS_OPEN)) + return ZFCP_ERP_SUCCEEDED; + break; + case ZFCP_ERP_STEP_PORT_CLOSING: + case ZFCP_ERP_STEP_PORT_OPENING: + case ZFCP_ERP_STEP_LUN_CLOSING: + case ZFCP_ERP_STEP_LUN_OPENING: + /* NOP */ + break; + } + return ZFCP_ERP_FAILED; +} + +static enum zfcp_erp_act_result zfcp_erp_port_strategy_close( + struct zfcp_erp_action *erp_action) +{ + int retval; + + retval = zfcp_fsf_close_port(erp_action); + if (retval == -ENOMEM) + return ZFCP_ERP_NOMEM; + erp_action->step = ZFCP_ERP_STEP_PORT_CLOSING; + if (retval) + return ZFCP_ERP_FAILED; + return ZFCP_ERP_CONTINUES; +} + +static enum zfcp_erp_act_result zfcp_erp_port_strategy_open_port( + struct zfcp_erp_action *erp_action) +{ + int retval; + + retval = zfcp_fsf_open_port(erp_action); + if (retval == -ENOMEM) + return ZFCP_ERP_NOMEM; + erp_action->step = ZFCP_ERP_STEP_PORT_OPENING; + if (retval) + return ZFCP_ERP_FAILED; + return ZFCP_ERP_CONTINUES; +} + +static int zfcp_erp_open_ptp_port(struct zfcp_erp_action *act) +{ + struct zfcp_adapter *adapter = act->adapter; + struct zfcp_port *port = act->port; + + if (port->wwpn != adapter->peer_wwpn) { + zfcp_erp_set_port_status(port, ZFCP_STATUS_COMMON_ERP_FAILED); + return ZFCP_ERP_FAILED; + } + port->d_id = adapter->peer_d_id; + return zfcp_erp_port_strategy_open_port(act); +} + +static enum zfcp_erp_act_result zfcp_erp_port_strategy_open_common( + struct zfcp_erp_action *act) +{ + struct zfcp_adapter *adapter = act->adapter; + struct zfcp_port *port = act->port; + int p_status = atomic_read(&port->status); + + switch (act->step) { + case ZFCP_ERP_STEP_UNINITIALIZED: + case ZFCP_ERP_STEP_PHYS_PORT_CLOSING: + case ZFCP_ERP_STEP_PORT_CLOSING: + if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_PTP) + return zfcp_erp_open_ptp_port(act); + if (!port->d_id) { + zfcp_fc_trigger_did_lookup(port); + return ZFCP_ERP_EXIT; + } + return zfcp_erp_port_strategy_open_port(act); + + case ZFCP_ERP_STEP_PORT_OPENING: + /* D_ID might have changed during open */ + if (p_status & ZFCP_STATUS_COMMON_OPEN) { + if (!port->d_id) { + zfcp_fc_trigger_did_lookup(port); + return ZFCP_ERP_EXIT; + } + return ZFCP_ERP_SUCCEEDED; + } + if (port->d_id && !(p_status & ZFCP_STATUS_COMMON_NOESC)) { + port->d_id = 0; + return ZFCP_ERP_FAILED; + } + /* no early return otherwise, continue after switch case */ + break; + case ZFCP_ERP_STEP_LUN_CLOSING: + case ZFCP_ERP_STEP_LUN_OPENING: + /* NOP */ + break; + } + return ZFCP_ERP_FAILED; +} + +static enum zfcp_erp_act_result zfcp_erp_port_strategy( + struct zfcp_erp_action *erp_action) +{ + struct zfcp_port *port = erp_action->port; + int p_status = atomic_read(&port->status); + + if ((p_status & ZFCP_STATUS_COMMON_NOESC) && + !(p_status & ZFCP_STATUS_COMMON_OPEN)) + goto close_init_done; + + switch (erp_action->step) { + case ZFCP_ERP_STEP_UNINITIALIZED: + if (p_status & ZFCP_STATUS_COMMON_OPEN) + return zfcp_erp_port_strategy_close(erp_action); + break; + + case ZFCP_ERP_STEP_PORT_CLOSING: + if (p_status & ZFCP_STATUS_COMMON_OPEN) + return ZFCP_ERP_FAILED; + break; + case ZFCP_ERP_STEP_PHYS_PORT_CLOSING: + case ZFCP_ERP_STEP_PORT_OPENING: + case ZFCP_ERP_STEP_LUN_CLOSING: + case ZFCP_ERP_STEP_LUN_OPENING: + /* NOP */ + break; + } + +close_init_done: + if (erp_action->status & ZFCP_STATUS_ERP_CLOSE_ONLY) + return ZFCP_ERP_EXIT; + + return zfcp_erp_port_strategy_open_common(erp_action); +} + +static void zfcp_erp_lun_strategy_clearstati(struct scsi_device *sdev) +{ + struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev); + + atomic_andnot(ZFCP_STATUS_COMMON_ACCESS_DENIED, + &zfcp_sdev->status); +} + +static enum zfcp_erp_act_result zfcp_erp_lun_strategy_close( + struct zfcp_erp_action *erp_action) +{ + int retval = zfcp_fsf_close_lun(erp_action); + if (retval == -ENOMEM) + return ZFCP_ERP_NOMEM; + erp_action->step = ZFCP_ERP_STEP_LUN_CLOSING; + if (retval) + return ZFCP_ERP_FAILED; + return ZFCP_ERP_CONTINUES; +} + +static enum zfcp_erp_act_result zfcp_erp_lun_strategy_open( + struct zfcp_erp_action *erp_action) +{ + int retval = zfcp_fsf_open_lun(erp_action); + if (retval == -ENOMEM) + return ZFCP_ERP_NOMEM; + erp_action->step = ZFCP_ERP_STEP_LUN_OPENING; + if (retval) + return ZFCP_ERP_FAILED; + return ZFCP_ERP_CONTINUES; +} + +static enum zfcp_erp_act_result zfcp_erp_lun_strategy( + struct zfcp_erp_action *erp_action) +{ + struct scsi_device *sdev = erp_action->sdev; + struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev); + + switch (erp_action->step) { + case ZFCP_ERP_STEP_UNINITIALIZED: + zfcp_erp_lun_strategy_clearstati(sdev); + if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_OPEN) + return zfcp_erp_lun_strategy_close(erp_action); + /* already closed */ + fallthrough; + case ZFCP_ERP_STEP_LUN_CLOSING: + if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_OPEN) + return ZFCP_ERP_FAILED; + if (erp_action->status & ZFCP_STATUS_ERP_CLOSE_ONLY) + return ZFCP_ERP_EXIT; + return zfcp_erp_lun_strategy_open(erp_action); + + case ZFCP_ERP_STEP_LUN_OPENING: + if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_OPEN) + return ZFCP_ERP_SUCCEEDED; + break; + case ZFCP_ERP_STEP_PHYS_PORT_CLOSING: + case ZFCP_ERP_STEP_PORT_CLOSING: + case ZFCP_ERP_STEP_PORT_OPENING: + /* NOP */ + break; + } + return ZFCP_ERP_FAILED; +} + +static enum zfcp_erp_act_result zfcp_erp_strategy_check_lun( + struct scsi_device *sdev, enum zfcp_erp_act_result result) +{ + struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev); + + switch (result) { + case ZFCP_ERP_SUCCEEDED : + atomic_set(&zfcp_sdev->erp_counter, 0); + zfcp_erp_lun_unblock(sdev); + break; + case ZFCP_ERP_FAILED : + atomic_inc(&zfcp_sdev->erp_counter); + if (atomic_read(&zfcp_sdev->erp_counter) > ZFCP_MAX_ERPS) { + dev_err(&zfcp_sdev->port->adapter->ccw_device->dev, + "ERP failed for LUN 0x%016Lx on " + "port 0x%016Lx\n", + (unsigned long long)zfcp_scsi_dev_lun(sdev), + (unsigned long long)zfcp_sdev->port->wwpn); + zfcp_erp_set_lun_status(sdev, + ZFCP_STATUS_COMMON_ERP_FAILED); + } + break; + case ZFCP_ERP_CONTINUES: + case ZFCP_ERP_EXIT: + case ZFCP_ERP_DISMISSED: + case ZFCP_ERP_NOMEM: + /* NOP */ + break; + } + + if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_ERP_FAILED) { + zfcp_erp_lun_block(sdev, 0); + result = ZFCP_ERP_EXIT; + } + return result; +} + +static enum zfcp_erp_act_result zfcp_erp_strategy_check_port( + struct zfcp_port *port, enum zfcp_erp_act_result result) +{ + switch (result) { + case ZFCP_ERP_SUCCEEDED : + atomic_set(&port->erp_counter, 0); + zfcp_erp_port_unblock(port); + break; + + case ZFCP_ERP_FAILED : + if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC) { + zfcp_erp_port_block(port, 0); + result = ZFCP_ERP_EXIT; + } + atomic_inc(&port->erp_counter); + if (atomic_read(&port->erp_counter) > ZFCP_MAX_ERPS) { + dev_err(&port->adapter->ccw_device->dev, + "ERP failed for remote port 0x%016Lx\n", + (unsigned long long)port->wwpn); + zfcp_erp_set_port_status(port, + ZFCP_STATUS_COMMON_ERP_FAILED); + } + break; + case ZFCP_ERP_CONTINUES: + case ZFCP_ERP_EXIT: + case ZFCP_ERP_DISMISSED: + case ZFCP_ERP_NOMEM: + /* NOP */ + break; + } + + if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED) { + zfcp_erp_port_block(port, 0); + result = ZFCP_ERP_EXIT; + } + return result; +} + +static enum zfcp_erp_act_result zfcp_erp_strategy_check_adapter( + struct zfcp_adapter *adapter, enum zfcp_erp_act_result result) +{ + switch (result) { + case ZFCP_ERP_SUCCEEDED : + atomic_set(&adapter->erp_counter, 0); + zfcp_erp_adapter_unblock(adapter); + break; + + case ZFCP_ERP_FAILED : + atomic_inc(&adapter->erp_counter); + if (atomic_read(&adapter->erp_counter) > ZFCP_MAX_ERPS) { + dev_err(&adapter->ccw_device->dev, + "ERP cannot recover an error " + "on the FCP device\n"); + zfcp_erp_set_adapter_status(adapter, + ZFCP_STATUS_COMMON_ERP_FAILED); + } + break; + case ZFCP_ERP_CONTINUES: + case ZFCP_ERP_EXIT: + case ZFCP_ERP_DISMISSED: + case ZFCP_ERP_NOMEM: + /* NOP */ + break; + } + + if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_FAILED) { + zfcp_erp_adapter_block(adapter, 0); + result = ZFCP_ERP_EXIT; + } + return result; +} + +static enum zfcp_erp_act_result zfcp_erp_strategy_check_target( + struct zfcp_erp_action *erp_action, enum zfcp_erp_act_result result) +{ + struct zfcp_adapter *adapter = erp_action->adapter; + struct zfcp_port *port = erp_action->port; + struct scsi_device *sdev = erp_action->sdev; + + switch (erp_action->type) { + + case ZFCP_ERP_ACTION_REOPEN_LUN: + result = zfcp_erp_strategy_check_lun(sdev, result); + break; + + case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED: + case ZFCP_ERP_ACTION_REOPEN_PORT: + result = zfcp_erp_strategy_check_port(port, result); + break; + + case ZFCP_ERP_ACTION_REOPEN_ADAPTER: + result = zfcp_erp_strategy_check_adapter(adapter, result); + break; + } + return result; +} + +static int zfcp_erp_strat_change_det(atomic_t *target_status, u32 erp_status) +{ + int status = atomic_read(target_status); + + if ((status & ZFCP_STATUS_COMMON_RUNNING) && + (erp_status & ZFCP_STATUS_ERP_CLOSE_ONLY)) + return 1; /* take it online */ + + if (!(status & ZFCP_STATUS_COMMON_RUNNING) && + !(erp_status & ZFCP_STATUS_ERP_CLOSE_ONLY)) + return 1; /* take it offline */ + + return 0; +} + +static enum zfcp_erp_act_result zfcp_erp_strategy_statechange( + struct zfcp_erp_action *act, enum zfcp_erp_act_result result) +{ + enum zfcp_erp_act_type type = act->type; + struct zfcp_adapter *adapter = act->adapter; + struct zfcp_port *port = act->port; + struct scsi_device *sdev = act->sdev; + struct zfcp_scsi_dev *zfcp_sdev; + u32 erp_status = act->status; + + switch (type) { + case ZFCP_ERP_ACTION_REOPEN_ADAPTER: + if (zfcp_erp_strat_change_det(&adapter->status, erp_status)) { + _zfcp_erp_adapter_reopen(adapter, + ZFCP_STATUS_COMMON_ERP_FAILED, + "ersscg1"); + return ZFCP_ERP_EXIT; + } + break; + + case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED: + case ZFCP_ERP_ACTION_REOPEN_PORT: + if (zfcp_erp_strat_change_det(&port->status, erp_status)) { + _zfcp_erp_port_reopen(port, + ZFCP_STATUS_COMMON_ERP_FAILED, + "ersscg2"); + return ZFCP_ERP_EXIT; + } + break; + + case ZFCP_ERP_ACTION_REOPEN_LUN: + zfcp_sdev = sdev_to_zfcp(sdev); + if (zfcp_erp_strat_change_det(&zfcp_sdev->status, erp_status)) { + _zfcp_erp_lun_reopen(sdev, + ZFCP_STATUS_COMMON_ERP_FAILED, + "ersscg3", 0); + return ZFCP_ERP_EXIT; + } + break; + } + return result; +} + +static void zfcp_erp_action_dequeue(struct zfcp_erp_action *erp_action) +{ + struct zfcp_adapter *adapter = erp_action->adapter; + struct zfcp_scsi_dev *zfcp_sdev; + + adapter->erp_total_count--; + if (erp_action->status & ZFCP_STATUS_ERP_LOWMEM) { + adapter->erp_low_mem_count--; + erp_action->status &= ~ZFCP_STATUS_ERP_LOWMEM; + } + + list_del(&erp_action->list); + zfcp_dbf_rec_run("eractd1", erp_action); + + switch (erp_action->type) { + case ZFCP_ERP_ACTION_REOPEN_LUN: + zfcp_sdev = sdev_to_zfcp(erp_action->sdev); + atomic_andnot(ZFCP_STATUS_COMMON_ERP_INUSE, + &zfcp_sdev->status); + break; + + case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED: + case ZFCP_ERP_ACTION_REOPEN_PORT: + atomic_andnot(ZFCP_STATUS_COMMON_ERP_INUSE, + &erp_action->port->status); + break; + + case ZFCP_ERP_ACTION_REOPEN_ADAPTER: + atomic_andnot(ZFCP_STATUS_COMMON_ERP_INUSE, + &erp_action->adapter->status); + break; + } +} + +/** + * zfcp_erp_try_rport_unblock - unblock rport if no more/new recovery + * @port: zfcp_port whose fc_rport we should try to unblock + */ +static void zfcp_erp_try_rport_unblock(struct zfcp_port *port) +{ + unsigned long flags; + struct zfcp_adapter *adapter = port->adapter; + int port_status; + struct Scsi_Host *shost = adapter->scsi_host; + struct scsi_device *sdev; + + write_lock_irqsave(&adapter->erp_lock, flags); + port_status = atomic_read(&port->status); + if ((port_status & ZFCP_STATUS_COMMON_UNBLOCKED) == 0 || + (port_status & (ZFCP_STATUS_COMMON_ERP_INUSE | + ZFCP_STATUS_COMMON_ERP_FAILED)) != 0) { + /* new ERP of severity >= port triggered elsewhere meanwhile or + * local link down (adapter erp_failed but not clear unblock) + */ + zfcp_dbf_rec_run_lvl(4, "ertru_p", &port->erp_action); + write_unlock_irqrestore(&adapter->erp_lock, flags); + return; + } + spin_lock(shost->host_lock); + __shost_for_each_device(sdev, shost) { + struct zfcp_scsi_dev *zsdev = sdev_to_zfcp(sdev); + int lun_status; + + if (sdev->sdev_state == SDEV_DEL || + sdev->sdev_state == SDEV_CANCEL) + continue; + if (zsdev->port != port) + continue; + /* LUN under port of interest */ + lun_status = atomic_read(&zsdev->status); + if ((lun_status & ZFCP_STATUS_COMMON_ERP_FAILED) != 0) + continue; /* unblock rport despite failed LUNs */ + /* LUN recovery not given up yet [maybe follow-up pending] */ + if ((lun_status & ZFCP_STATUS_COMMON_UNBLOCKED) == 0 || + (lun_status & ZFCP_STATUS_COMMON_ERP_INUSE) != 0) { + /* LUN blocked: + * not yet unblocked [LUN recovery pending] + * or meanwhile blocked [new LUN recovery triggered] + */ + zfcp_dbf_rec_run_lvl(4, "ertru_l", &zsdev->erp_action); + spin_unlock(shost->host_lock); + write_unlock_irqrestore(&adapter->erp_lock, flags); + return; + } + } + /* now port has no child or all children have completed recovery, + * and no ERP of severity >= port was meanwhile triggered elsewhere + */ + zfcp_scsi_schedule_rport_register(port); + spin_unlock(shost->host_lock); + write_unlock_irqrestore(&adapter->erp_lock, flags); +} + +static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act, + enum zfcp_erp_act_result result) +{ + struct zfcp_adapter *adapter = act->adapter; + struct zfcp_port *port = act->port; + struct scsi_device *sdev = act->sdev; + + switch (act->type) { + case ZFCP_ERP_ACTION_REOPEN_LUN: + if (!(act->status & ZFCP_STATUS_ERP_NO_REF)) + scsi_device_put(sdev); + zfcp_erp_try_rport_unblock(port); + break; + + case ZFCP_ERP_ACTION_REOPEN_PORT: + /* This switch case might also happen after a forced reopen + * was successfully done and thus overwritten with a new + * non-forced reopen at `ersfs_2'. In this case, we must not + * do the clean-up of the non-forced version. + */ + if (act->step != ZFCP_ERP_STEP_UNINITIALIZED) + if (result == ZFCP_ERP_SUCCEEDED) + zfcp_erp_try_rport_unblock(port); + fallthrough; + case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED: + put_device(&port->dev); + break; + + case ZFCP_ERP_ACTION_REOPEN_ADAPTER: + if (result == ZFCP_ERP_SUCCEEDED) { + register_service_level(&adapter->service_level); + zfcp_fc_conditional_port_scan(adapter); + queue_work(adapter->work_queue, &adapter->ns_up_work); + } else + unregister_service_level(&adapter->service_level); + + kref_put(&adapter->ref, zfcp_adapter_release); + break; + } +} + +static enum zfcp_erp_act_result zfcp_erp_strategy_do_action( + struct zfcp_erp_action *erp_action) +{ + switch (erp_action->type) { + case ZFCP_ERP_ACTION_REOPEN_ADAPTER: + return zfcp_erp_adapter_strategy(erp_action); + case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED: + return zfcp_erp_port_forced_strategy(erp_action); + case ZFCP_ERP_ACTION_REOPEN_PORT: + return zfcp_erp_port_strategy(erp_action); + case ZFCP_ERP_ACTION_REOPEN_LUN: + return zfcp_erp_lun_strategy(erp_action); + } + return ZFCP_ERP_FAILED; +} + +static enum zfcp_erp_act_result zfcp_erp_strategy( + struct zfcp_erp_action *erp_action) +{ + enum zfcp_erp_act_result result; + unsigned long flags; + struct zfcp_adapter *adapter = erp_action->adapter; + + kref_get(&adapter->ref); + + write_lock_irqsave(&adapter->erp_lock, flags); + zfcp_erp_strategy_check_fsfreq(erp_action); + + if (erp_action->status & ZFCP_STATUS_ERP_DISMISSED) { + zfcp_erp_action_dequeue(erp_action); + result = ZFCP_ERP_DISMISSED; + goto unlock; + } + + if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT) { + result = ZFCP_ERP_FAILED; + goto check_target; + } + + zfcp_erp_action_to_running(erp_action); + + /* no lock to allow for blocking operations */ + write_unlock_irqrestore(&adapter->erp_lock, flags); + result = zfcp_erp_strategy_do_action(erp_action); + write_lock_irqsave(&adapter->erp_lock, flags); + + if (erp_action->status & ZFCP_STATUS_ERP_DISMISSED) + result = ZFCP_ERP_CONTINUES; + + switch (result) { + case ZFCP_ERP_NOMEM: + if (!(erp_action->status & ZFCP_STATUS_ERP_LOWMEM)) { + ++adapter->erp_low_mem_count; + erp_action->status |= ZFCP_STATUS_ERP_LOWMEM; + } + if (adapter->erp_total_count == adapter->erp_low_mem_count) + _zfcp_erp_adapter_reopen(adapter, 0, "erstgy1"); + else { + zfcp_erp_strategy_memwait(erp_action); + result = ZFCP_ERP_CONTINUES; + } + goto unlock; + + case ZFCP_ERP_CONTINUES: + if (erp_action->status & ZFCP_STATUS_ERP_LOWMEM) { + --adapter->erp_low_mem_count; + erp_action->status &= ~ZFCP_STATUS_ERP_LOWMEM; + } + goto unlock; + case ZFCP_ERP_SUCCEEDED: + case ZFCP_ERP_FAILED: + case ZFCP_ERP_EXIT: + case ZFCP_ERP_DISMISSED: + /* NOP */ + break; + } + +check_target: + result = zfcp_erp_strategy_check_target(erp_action, result); + zfcp_erp_action_dequeue(erp_action); + result = zfcp_erp_strategy_statechange(erp_action, result); + if (result == ZFCP_ERP_EXIT) + goto unlock; + if (result == ZFCP_ERP_SUCCEEDED) + zfcp_erp_strategy_followup_success(erp_action); + if (result == ZFCP_ERP_FAILED) + zfcp_erp_strategy_followup_failed(erp_action); + + unlock: + write_unlock_irqrestore(&adapter->erp_lock, flags); + + if (result != ZFCP_ERP_CONTINUES) + zfcp_erp_action_cleanup(erp_action, result); + + kref_put(&adapter->ref, zfcp_adapter_release); + return result; +} + +static int zfcp_erp_thread(void *data) +{ + struct zfcp_adapter *adapter = (struct zfcp_adapter *) data; + struct zfcp_erp_action *act; + unsigned long flags; + + for (;;) { + wait_event_interruptible(adapter->erp_ready_wq, + !list_empty(&adapter->erp_ready_head) || + kthread_should_stop()); + + if (kthread_should_stop()) + break; + + write_lock_irqsave(&adapter->erp_lock, flags); + act = list_first_entry_or_null(&adapter->erp_ready_head, + struct zfcp_erp_action, list); + write_unlock_irqrestore(&adapter->erp_lock, flags); + + if (act) { + /* there is more to come after dismission, no notify */ + if (zfcp_erp_strategy(act) != ZFCP_ERP_DISMISSED) + zfcp_erp_wakeup(adapter); + } + } + + return 0; +} + +/** + * zfcp_erp_thread_setup - Start ERP thread for adapter + * @adapter: Adapter to start the ERP thread for + * + * Return: 0 on success, or error code from kthread_run(). + */ +int zfcp_erp_thread_setup(struct zfcp_adapter *adapter) +{ + struct task_struct *thread; + + thread = kthread_run(zfcp_erp_thread, adapter, "zfcperp%s", + dev_name(&adapter->ccw_device->dev)); + if (IS_ERR(thread)) { + dev_err(&adapter->ccw_device->dev, + "Creating an ERP thread for the FCP device failed.\n"); + return PTR_ERR(thread); + } + + adapter->erp_thread = thread; + return 0; +} + +/** + * zfcp_erp_thread_kill - Stop ERP thread. + * @adapter: Adapter where the ERP thread should be stopped. + * + * The caller of this routine ensures that the specified adapter has + * been shut down and that this operation has been completed. Thus, + * there are no pending erp_actions which would need to be handled + * here. + */ +void zfcp_erp_thread_kill(struct zfcp_adapter *adapter) +{ + kthread_stop(adapter->erp_thread); + adapter->erp_thread = NULL; + WARN_ON(!list_empty(&adapter->erp_ready_head)); + WARN_ON(!list_empty(&adapter->erp_running_head)); +} + +/** + * zfcp_erp_wait - wait for completion of error recovery on an adapter + * @adapter: adapter for which to wait for completion of its error recovery + */ +void zfcp_erp_wait(struct zfcp_adapter *adapter) +{ + wait_event(adapter->erp_done_wqh, + !(atomic_read(&adapter->status) & + ZFCP_STATUS_ADAPTER_ERP_PENDING)); +} + +/** + * zfcp_erp_set_adapter_status - set adapter status bits + * @adapter: adapter to change the status + * @mask: status bits to change + * + * Changes in common status bits are propagated to attached ports and LUNs. + */ +void zfcp_erp_set_adapter_status(struct zfcp_adapter *adapter, u32 mask) +{ + struct zfcp_port *port; + struct scsi_device *sdev; + unsigned long flags; + u32 common_mask = mask & ZFCP_COMMON_FLAGS; + + atomic_or(mask, &adapter->status); + + if (!common_mask) + return; + + read_lock_irqsave(&adapter->port_list_lock, flags); + list_for_each_entry(port, &adapter->port_list, list) + atomic_or(common_mask, &port->status); + read_unlock_irqrestore(&adapter->port_list_lock, flags); + + /* + * if `scsi_host` is missing, xconfig/xport data has never completed + * yet, so we can't access it, but there are also no SDEVs yet + */ + if (adapter->scsi_host == NULL) + return; + + spin_lock_irqsave(adapter->scsi_host->host_lock, flags); + __shost_for_each_device(sdev, adapter->scsi_host) + atomic_or(common_mask, &sdev_to_zfcp(sdev)->status); + spin_unlock_irqrestore(adapter->scsi_host->host_lock, flags); +} + +/** + * zfcp_erp_clear_adapter_status - clear adapter status bits + * @adapter: adapter to change the status + * @mask: status bits to change + * + * Changes in common status bits are propagated to attached ports and LUNs. + */ +void zfcp_erp_clear_adapter_status(struct zfcp_adapter *adapter, u32 mask) +{ + struct zfcp_port *port; + struct scsi_device *sdev; + unsigned long flags; + u32 common_mask = mask & ZFCP_COMMON_FLAGS; + u32 clear_counter = mask & ZFCP_STATUS_COMMON_ERP_FAILED; + + atomic_andnot(mask, &adapter->status); + + if (!common_mask) + return; + + if (clear_counter) + atomic_set(&adapter->erp_counter, 0); + + read_lock_irqsave(&adapter->port_list_lock, flags); + list_for_each_entry(port, &adapter->port_list, list) { + atomic_andnot(common_mask, &port->status); + if (clear_counter) + atomic_set(&port->erp_counter, 0); + } + read_unlock_irqrestore(&adapter->port_list_lock, flags); + + /* + * if `scsi_host` is missing, xconfig/xport data has never completed + * yet, so we can't access it, but there are also no SDEVs yet + */ + if (adapter->scsi_host == NULL) + return; + + spin_lock_irqsave(adapter->scsi_host->host_lock, flags); + __shost_for_each_device(sdev, adapter->scsi_host) { + atomic_andnot(common_mask, &sdev_to_zfcp(sdev)->status); + if (clear_counter) + atomic_set(&sdev_to_zfcp(sdev)->erp_counter, 0); + } + spin_unlock_irqrestore(adapter->scsi_host->host_lock, flags); +} + +/** + * zfcp_erp_set_port_status - set port status bits + * @port: port to change the status + * @mask: status bits to change + * + * Changes in common status bits are propagated to attached LUNs. + */ +void zfcp_erp_set_port_status(struct zfcp_port *port, u32 mask) +{ + struct scsi_device *sdev; + u32 common_mask = mask & ZFCP_COMMON_FLAGS; + unsigned long flags; + + atomic_or(mask, &port->status); + + if (!common_mask) + return; + + spin_lock_irqsave(port->adapter->scsi_host->host_lock, flags); + __shost_for_each_device(sdev, port->adapter->scsi_host) + if (sdev_to_zfcp(sdev)->port == port) + atomic_or(common_mask, + &sdev_to_zfcp(sdev)->status); + spin_unlock_irqrestore(port->adapter->scsi_host->host_lock, flags); +} + +/** + * zfcp_erp_clear_port_status - clear port status bits + * @port: adapter to change the status + * @mask: status bits to change + * + * Changes in common status bits are propagated to attached LUNs. + */ +void zfcp_erp_clear_port_status(struct zfcp_port *port, u32 mask) +{ + struct scsi_device *sdev; + u32 common_mask = mask & ZFCP_COMMON_FLAGS; + u32 clear_counter = mask & ZFCP_STATUS_COMMON_ERP_FAILED; + unsigned long flags; + + atomic_andnot(mask, &port->status); + + if (!common_mask) + return; + + if (clear_counter) + atomic_set(&port->erp_counter, 0); + + spin_lock_irqsave(port->adapter->scsi_host->host_lock, flags); + __shost_for_each_device(sdev, port->adapter->scsi_host) + if (sdev_to_zfcp(sdev)->port == port) { + atomic_andnot(common_mask, + &sdev_to_zfcp(sdev)->status); + if (clear_counter) + atomic_set(&sdev_to_zfcp(sdev)->erp_counter, 0); + } + spin_unlock_irqrestore(port->adapter->scsi_host->host_lock, flags); +} + +/** + * zfcp_erp_set_lun_status - set lun status bits + * @sdev: SCSI device / lun to set the status bits + * @mask: status bits to change + */ +void zfcp_erp_set_lun_status(struct scsi_device *sdev, u32 mask) +{ + struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev); + + atomic_or(mask, &zfcp_sdev->status); +} + +/** + * zfcp_erp_clear_lun_status - clear lun status bits + * @sdev: SCSi device / lun to clear the status bits + * @mask: status bits to change + */ +void zfcp_erp_clear_lun_status(struct scsi_device *sdev, u32 mask) +{ + struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev); + + atomic_andnot(mask, &zfcp_sdev->status); + + if (mask & ZFCP_STATUS_COMMON_ERP_FAILED) + atomic_set(&zfcp_sdev->erp_counter, 0); +} + +/** + * zfcp_erp_adapter_reset_sync() - Really reopen adapter and wait. + * @adapter: Pointer to zfcp_adapter to reopen. + * @dbftag: Trace tag string of length %ZFCP_DBF_TAG_LEN. + */ +void zfcp_erp_adapter_reset_sync(struct zfcp_adapter *adapter, char *dbftag) +{ + zfcp_erp_set_adapter_status(adapter, ZFCP_STATUS_COMMON_RUNNING); + zfcp_erp_adapter_reopen(adapter, ZFCP_STATUS_COMMON_ERP_FAILED, dbftag); + zfcp_erp_wait(adapter); +} |