[PATCH 3/4] fastboot: make the libata port scan asynchronous

Arjan van de Ven
2009-01-04T17:30:08Z

>From 2eb80a6c7b7c33a9053cfd286169d5163027f0cd Mon Sep 17 00:00:00 2001
From: Arjan van de Ven <arjan@linux.intel.com>
Date: Sun, 4 Jan 2009 05:32:28 -0800
Subject: [PATCH] fastboot: make the libata port scan asynchronous

This patch makes the libata port scanning asynchronous (per device).
There is a synchronization point before doing the actual disk scan
so that device ordering is not affected.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
---
drivers/ata/libata-core.c | 84 ++++++++++++++++++++++++--------------------
1 files changed, 46 insertions(+), 38 deletions(-)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index fecca42..fe2c208 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -56,6 +56,7 @@
#include <linux/workqueue.h>
#include <linux/scatterlist.h>
#include <linux/io.h>
+#include <linux/async.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_host.h>
@@ -5909,6 +5910,48 @@ void ata_host_init(struct ata_host *host, struct device *dev,
host->ops = ops;
}

+
+void async_port_probe(void *data, async_cookie_t cookie)
+{
+ int rc;
+ struct ata_port *ap = data;
+ /* probe */
+ if (ap->ops->error_handler) {
+ struct ata_eh_info *ehi = &ap->link.eh_info;
+ unsigned long flags;
+
+ ata_port_probe(ap);
+
+ /* kick EH for boot probing */
+ spin_lock_irqsave(ap->lock, flags);
+
+ ehi->probe_mask |= ATA_ALL_DEVICES;
+ ehi->action |= ATA_EH_RESET | ATA_EH_LPM;
+ ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
+
+ ap->pflags &= ~ATA_PFLAG_INITIALIZING;
+ ap->pflags |= ATA_PFLAG_LOADING;
+ ata_port_schedule_eh(ap);
+
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ /* wait for EH to finish */
+ ata_port_wait_eh(ap);
+ } else {
+ DPRINTK("ata%u: bus probe begin\n", ap->print_id);
+ rc = ata_bus_probe(ap);
+ DPRINTK("ata%u: bus probe end\n", ap->print_id);
+
+ if (rc) {
+ /* FIXME: do something useful here?
+ * Current libata behavior will
+ * tear down everything when
+ * the module is removed
+ * or the h/w is unplugged.
+ */
+ }
+ }
+}
/**
* ata_host_register - register initialized ATA host
* @host: ATA host to register
@@ -5988,45 +6031,9 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
DPRINTK("probe begin\n");
for (i = 0; i < host->n_ports; i++) {
struct ata_port *ap = host->ports[i];
-
- /* probe */
- if (ap->ops->error_handler) {
- struct ata_eh_info *ehi = &ap->link.eh_info;
- unsigned long flags;
-
- ata_port_probe(ap);
-
- /* kick EH for boot probing */
- spin_lock_irqsave(ap->lock, flags);
-
- ehi->probe_mask |= ATA_ALL_DEVICES;
- ehi->action |= ATA_EH_RESET | ATA_EH_LPM;
- ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
-
- ap->pflags &= ~ATA_PFLAG_INITIALIZING;
- ap->pflags |= ATA_PFLAG_LOADING;
- ata_port_schedule_eh(ap);
-
- spin_unlock_irqrestore(ap->lock, flags);
-
- /* wait for EH to finish */
- ata_port_wait_eh(ap);
- } else {
- DPRINTK("ata%u: bus probe begin\n", ap->print_id);
- rc = ata_bus_probe(ap);
- DPRINTK("ata%u: bus probe end\n", ap->print_id);
-
- if (rc) {
- /* FIXME: do something useful here?
- * Current libata behavior will
- * tear down everything when
- * the module is removed
- * or the h/w is unplugged.
- */
- }
- }
+ async_schedule(async_port_probe, ap);
}
-
+ async_synchronize_full();
/* probes are done, now scan each port's disk(s) */
DPRINTK("host probe begin\n");
for (i = 0; i < host->n_ports; i++) {
@@ -6034,6 +6041,7 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)

ata_scsi_scan_host(ap, 1);
}
+ DPRINTK("host probe end\n");

return 0;
}
--
1.6.0.6

--
Arjan van de Ven Intel Open Source Technology Centre
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