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-rw-r--r--drivers/ata/libata-core.c30
-rw-r--r--drivers/ata/libata-eh.c44
-rw-r--r--drivers/ata/libata.h2
-rw-r--r--include/linux/libata.h5
4 files changed, 80 insertions, 1 deletions
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 42d9ce2..7f77c67 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -1628,8 +1628,14 @@ unsigned ata_exec_internal_sg(struct ata_device *dev,
}
}
+ if (ap->ops->error_handler)
+ ata_eh_release(ap);
+
rc = wait_for_completion_timeout(&wait, msecs_to_jiffies(timeout));
+ if (ap->ops->error_handler)
+ ata_eh_acquire(ap);
+
ata_sff_flush_pio_task(ap);
if (!rc) {
@@ -5570,6 +5576,7 @@ struct ata_host *ata_host_alloc(struct device *dev, int max_ports)
dev_set_drvdata(dev, host);
spin_lock_init(&host->lock);
+ mutex_init(&host->eh_mutex);
host->dev = dev;
host->n_ports = max_ports;
@@ -5867,6 +5874,7 @@ void ata_host_init(struct ata_host *host, struct device *dev,
unsigned long flags, struct ata_port_operations *ops)
{
spin_lock_init(&host->lock);
+ mutex_init(&host->eh_mutex);
host->dev = dev;
host->flags = flags;
host->ops = ops;
@@ -6483,9 +6491,31 @@ int ata_ratelimit(void)
return __ratelimit(&ratelimit);
}
+/**
+ * ata_msleep - ATA EH owner aware msleep
+ * @ap: ATA port to attribute the sleep to
+ * @msecs: duration to sleep in milliseconds
+ *
+ * Sleeps @msecs. If the current task is owner of @ap's EH, the
+ * ownership is released before going to sleep and reacquired
+ * after the sleep is complete. IOW, other ports sharing the
+ * @ap->host will be allowed to own the EH while this task is
+ * sleeping.
+ *
+ * LOCKING:
+ * Might sleep.
+ */
void ata_msleep(struct ata_port *ap, unsigned int msecs)
{
+ bool owns_eh = ap && ap->host->eh_owner == current;
+
+ if (owns_eh)
+ ata_eh_release(ap);
+
msleep(msecs);
+
+ if (owns_eh)
+ ata_eh_acquire(ap);
}
/**
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 6780f4d..5e59050 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -463,6 +463,41 @@ static void ata_eh_clear_action(struct ata_link *link, struct ata_device *dev,
}
/**
+ * ata_eh_acquire - acquire EH ownership
+ * @ap: ATA port to acquire EH ownership for
+ *
+ * Acquire EH ownership for @ap. This is the basic exclusion
+ * mechanism for ports sharing a host. Only one port hanging off
+ * the same host can claim the ownership of EH.
+ *
+ * LOCKING:
+ * EH context.
+ */
+void ata_eh_acquire(struct ata_port *ap)
+{
+ mutex_lock(&ap->host->eh_mutex);
+ WARN_ON_ONCE(ap->host->eh_owner);
+ ap->host->eh_owner = current;
+}
+
+/**
+ * ata_eh_release - release EH ownership
+ * @ap: ATA port to release EH ownership for
+ *
+ * Release EH ownership for @ap if the caller. The caller must
+ * have acquired EH ownership using ata_eh_acquire() previously.
+ *
+ * LOCKING:
+ * EH context.
+ */
+void ata_eh_release(struct ata_port *ap)
+{
+ WARN_ON_ONCE(ap->host->eh_owner != current);
+ ap->host->eh_owner = NULL;
+ mutex_unlock(&ap->host->eh_mutex);
+}
+
+/**
* ata_scsi_timed_out - SCSI layer time out callback
* @cmd: timed out SCSI command
*
@@ -639,11 +674,13 @@ void ata_scsi_error(struct Scsi_Host *host)
/* If we timed raced normal completion and there is nothing to
recover nr_timedout == 0 why exactly are we doing error recovery ? */
- repeat:
/* invoke error handler */
if (ap->ops->error_handler) {
struct ata_link *link;
+ /* acquire EH ownership */
+ ata_eh_acquire(ap);
+ repeat:
/* kill fast drain timer */
del_timer_sync(&ap->fastdrain_timer);
@@ -718,6 +755,7 @@ void ata_scsi_error(struct Scsi_Host *host)
host->host_eh_scheduled = 0;
spin_unlock_irqrestore(ap->lock, flags);
+ ata_eh_release(ap);
} else {
WARN_ON(ata_qc_from_tag(ap, ap->link.active_tag) == NULL);
ap->ops->eng_timeout(ap);
@@ -2818,8 +2856,10 @@ int ata_eh_reset(struct ata_link *link, int classify,
"reset failed (errno=%d), retrying in %u secs\n",
rc, DIV_ROUND_UP(jiffies_to_msecs(delta), 1000));
+ ata_eh_release(ap);
while (delta)
delta = schedule_timeout_uninterruptible(delta);
+ ata_eh_acquire(ap);
}
if (try == max_tries - 1) {
@@ -3635,8 +3675,10 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
if (time_before_eq(deadline, now))
break;
+ ata_eh_release(ap);
deadline = wait_for_completion_timeout(&ap->park_req_pending,
deadline - now);
+ ata_eh_acquire(ap);
} while (deadline);
ata_for_each_link(link, ap, EDGE) {
ata_for_each_dev(dev, link, ALL) {
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 7c070a4..a9be110 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -145,6 +145,8 @@ extern int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
/* libata-eh.c */
extern unsigned long ata_internal_cmd_timeout(struct ata_device *dev, u8 cmd);
extern void ata_internal_cmd_timed_out(struct ata_device *dev, u8 cmd);
+extern void ata_eh_acquire(struct ata_port *ap);
+extern void ata_eh_release(struct ata_port *ap);
extern enum blk_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd);
extern void ata_scsi_error(struct Scsi_Host *host);
extern void ata_port_wait_eh(struct ata_port *ap);
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 2fbd22b..52112d3 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -37,6 +37,7 @@
#include <scsi/scsi_host.h>
#include <linux/acpi.h>
#include <linux/cdrom.h>
+#include <linux/sched.h>
/*
* Define if arch has non-standard setup. This is a _PCI_ standard
@@ -535,6 +536,10 @@ struct ata_host {
void *private_data;
struct ata_port_operations *ops;
unsigned long flags;
+
+ struct mutex eh_mutex;
+ struct task_struct *eh_owner;
+
#ifdef CONFIG_ATA_ACPI
acpi_handle acpi_handle;
#endif
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