Better handling DEAD IOC (PCI-E LInk down) error condition
Detection of Dead IOC has been done in fault_reset_work thread.
If IOC Doorbell is 0xFFFFFFFF, it will be detected as non-operation/DEAD IOC.
When a DEAD IOC is detected, the code is modified to remove that IOC and
all its attached devices from OS.
The PCI layer API pci_remove_bus_device() is called to remove the dead IOC.
Signed-off-by: Nagalakshmi Nandigama <nagalakshmi.nandigama@xxxxxxx>
---
diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.c b/drivers/scsi/mpt2sas/mpt2sas_base.c
index 54b70ae..6c0d8f6 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.c
@@ -58,6 +58,7 @@
#include <linux/sort.h>
#include <linux/io.h>
#include <linux/time.h>
+#include <linux/kthread.h>
#include <linux/aer.h>
#include "mpt2sas_base.h"
@@ -121,10 +122,34 @@ _scsih_set_fwfault_debug(const char *val, struct kernel_param *kp)
ioc->fwfault_debug = mpt2sas_fwfault_debug;
return 0;
}
+
module_param_call(mpt2sas_fwfault_debug, _scsih_set_fwfault_debug,
param_get_int, &mpt2sas_fwfault_debug, 0644);
/**
+ * mpt2sas_remove_dead_ioc_func - kthread context to remove dead ioc
+ * @arg: input argument, used to derive ioc
+ *
+ * Return 0 if controller is removed from pci subsystem.
+ * Return -1 for other case.
+ */
+static int mpt2sas_remove_dead_ioc_func(void *arg)
+{
+ struct MPT2SAS_ADAPTER *ioc = (struct MPT2SAS_ADAPTER *)arg;
+ struct pci_dev *pdev;
+
+ if ((ioc == NULL))
+ return -1;
+
+ pdev = ioc->pdev;
+ if ((pdev == NULL))
+ return -1;
+ pci_remove_bus_device(pdev);
+ return 0;
+}
+
+
+/**
* _base_fault_reset_work - workq handling ioc fault conditions
* @work: input argument, used to derive ioc
* Context: sleep.
@@ -139,6 +164,7 @@ _base_fault_reset_work(struct work_struct *work)
unsigned long flags;
u32 doorbell;
int rc;
+ struct task_struct *p;
spin_lock_irqsave(&ioc->ioc_reset_in_progress_lock, flags);
if (ioc->shost_recovery)
@@ -146,6 +172,39 @@ _base_fault_reset_work(struct work_struct *work)
spin_unlock_irqrestore(&ioc->ioc_reset_in_progress_lock, flags);
doorbell = mpt2sas_base_get_iocstate(ioc, 0);
+ if ((doorbell & MPI2_IOC_STATE_MASK) == MPI2_IOC_STATE_MASK) {
+ printk(MPT2SAS_INFO_FMT "%s : SAS host is non-operational !!!!\n",
+ ioc->name, __func__);
+
+ /*
+ * Call _scsih_flush_pending_cmds callback so that we flush all
+ * pending commands back to OS. This call is required to aovid
+ * deadlock at block layer. Dead IOC will fail to do diag reset,
+ * and this call is safe since dead ioc will never return any
+ * command back from HW.
+ */
+ ioc->schedule_dead_ioc_flush_running_cmds(ioc);
+ /*
+ * Set remove_host flag early since kernel thread will
+ * take some time to execute.
+ */
+ ioc->remove_host = 1;
+ /*Remove the Dead Host */
+ p = kthread_run(mpt2sas_remove_dead_ioc_func, ioc,
+ "mpt2sas_dead_ioc_%d", ioc->id);
+ if (IS_ERR(p)) {
+ printk(MPT2SAS_ERR_FMT
+ "%s: Running mpt2sas_dead_ioc thread failed !!!!\n",
+ ioc->name, __func__);
+ } else {
+ printk(MPT2SAS_ERR_FMT
+ "%s: Running mpt2sas_dead_ioc thread success !!!!\n",
+ ioc->name, __func__);
+ }
+
+ return; /* don't rearm timer */
+ }
+
if ((doorbell & MPI2_IOC_STATE_MASK) == MPI2_IOC_STATE_FAULT) {
rc = mpt2sas_base_hard_reset_handler(ioc, CAN_SLEEP,
FORCE_BIG_HAMMER);
diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.h b/drivers/scsi/mpt2sas/mpt2sas_base.h
index 3c3babc..61e5b24 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.h
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.h
@@ -623,6 +623,7 @@ enum mutex_type {
TM_MUTEX_ON = 1,
};
+typedef void (*MPT2SAS_FLUSH_RUNNING_CMDS)(struct MPT2SAS_ADAPTER *ioc);
/**
* struct MPT2SAS_ADAPTER - per adapter struct
* @list: ioc_list
@@ -665,6 +666,7 @@ enum mutex_type {
* @msix_vector_count: number msix vectors
* @cpu_msix_table: table for mapping cpus to msix index
* @cpu_msix_table_sz: table size
+ * @schedule_dead_ioc_flush_running_cmds: callback to flush pending commands
* @scsi_io_cb_idx: shost generated commands
* @tm_cb_idx: task management commands
* @scsih_cb_idx: scsih internal commands
@@ -816,6 +818,7 @@ struct MPT2SAS_ADAPTER {
resource_size_t **reply_post_host_index;
u16 cpu_msix_table_sz;
u32 ioc_reset_count;
+ MPT2SAS_FLUSH_RUNNING_CMDS schedule_dead_ioc_flush_running_cmds;
/* internal commands, callback index */
u8 scsi_io_cb_idx;
diff --git a/drivers/scsi/mpt2sas/mpt2sas_scsih.c b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
index 341240f..447a769 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_scsih.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
@@ -7924,6 +7924,7 @@ _scsih_probe(struct pci_dev *pdev, const struct pci_device_id *id)
ioc->tm_tr_volume_cb_idx = tm_tr_volume_cb_idx;
ioc->tm_sas_control_cb_idx = tm_sas_control_cb_idx;
ioc->logging_level = logging_level;
+ ioc->schedule_dead_ioc_flush_running_cmds = &_scsih_flush_running_cmds;
/* misc semaphores and spin locks */
mutex_init(&ioc->reset_in_progress_mutex);
spin_lock_init(&ioc->ioc_reset_in_progress_lock);
--
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