This patch is originally from Alan Stern (as569). It has been rediffed against a current tree.
This patch converts usb-storage to use the kthread API for creating its
control and scanning threads. The new code doesn't use kthread_stop
because the threads need (or will need in the future) to exit
asynchronously.
Greg, please apply.
Matt
Signed-off-by: Alan Stern <[EMAIL PROTECTED]>
Signed-off-by: Matthew Dharm <[EMAIL PROTECTED]>
Index: usb-2.6/drivers/usb/storage/usb.h
===================================================================
--- usb-2.6.orig/drivers/usb/storage/usb.h
+++ usb-2.6/drivers/usb/storage/usb.h
@@ -160,9 +160,6 @@ struct us_data {
struct scsi_cmnd *srb; /* current srb */
unsigned int tag; /* current dCBWTag */
- /* thread information */
- int pid; /* control thread */
-
/* control and bulk communications data */
struct urb *current_urb; /* USB requests */
struct usb_ctrlrequest *cr; /* control requests */
Index: usb-2.6/drivers/usb/storage/usb.c
===================================================================
--- usb-2.6.orig/drivers/usb/storage/usb.c
+++ usb-2.6/drivers/usb/storage/usb.c
@@ -54,6 +54,7 @@
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
+#include <linux/kthread.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
@@ -310,22 +311,7 @@ static int usb_stor_control_thread(void
struct us_data *us = (struct us_data *)__us;
struct Scsi_Host *host = us_to_host(us);
- lock_kernel();
-
- /*
- * This thread doesn't need any user-level access,
- * so get rid of all our resources.
- */
- daemonize("usb-storage");
current->flags |= PF_NOFREEZE;
- unlock_kernel();
-
- /* acquire a reference to the host, so it won't be deallocated
- * until we're ready to exit */
- scsi_host_get(host);
-
- /* signal that we've started the thread */
- complete(&(us->notify));
for(;;) {
US_DEBUGP("*** thread sleeping.\n");
@@ -762,6 +748,7 @@ static int get_pipes(struct us_data *us)
static int usb_stor_acquire_resources(struct us_data *us)
{
int p;
+ struct task_struct *th;
us->current_urb = usb_alloc_urb(0, GFP_KERNEL);
if (!us->current_urb) {
@@ -790,17 +777,19 @@ static int usb_stor_acquire_resources(st
up(&us->dev_semaphore);
/* Start up our control thread */
- p = kernel_thread(usb_stor_control_thread, us, CLONE_VM);
- if (p < 0) {
+ th = kthread_create(usb_stor_control_thread, us, "usb-storage");
+ if (IS_ERR(th)) {
printk(KERN_WARNING USB_STORAGE
"Unable to start control thread\n");
- return p;
+ return PTR_ERR(th);
}
- us->pid = p;
- atomic_inc(&total_threads);
- /* Wait for the thread to start */
- wait_for_completion(&(us->notify));
+ /* Take a reference to the host for the control thread and
+ * count it among all the threads we have launched. Then
+ * start it up. */
+ scsi_host_get(us_to_host(us));
+ atomic_inc(&total_threads);
+ wake_up_process(th);
return 0;
}
@@ -894,21 +883,6 @@ static int usb_stor_scan_thread(void * _
{
struct us_data *us = (struct us_data *)__us;
- /*
- * This thread doesn't need any user-level access,
- * so get rid of all our resources.
- */
- lock_kernel();
- daemonize("usb-stor-scan");
- unlock_kernel();
-
- /* Acquire a reference to the host, so it won't be deallocated
- * until we're ready to exit */
- scsi_host_get(us_to_host(us));
-
- /* Signal that we've started the thread */
- complete(&(us->notify));
-
printk(KERN_DEBUG
"usb-storage: device found at %d\n", us->pusb_dev->devnum);
@@ -945,6 +919,7 @@ static int storage_probe(struct usb_inte
struct us_data *us;
const int id_index = id - storage_usb_ids;
int result;
+ struct task_struct *th;
US_DEBUGP("USB Mass Storage device detected\n");
@@ -1025,17 +1000,21 @@ static int storage_probe(struct usb_inte
}
/* Start up the thread for delayed SCSI-device scanning */
- result = kernel_thread(usb_stor_scan_thread, us, CLONE_VM);
- if (result < 0) {
+ th = kthread_create(usb_stor_scan_thread, us, "usb-stor-scan");
+ if (IS_ERR(th)) {
printk(KERN_WARNING USB_STORAGE
"Unable to start the device-scanning thread\n");
quiesce_and_remove_host(us);
+ result = PTR_ERR(th);
goto BadDevice;
}
- atomic_inc(&total_threads);
- /* Wait for the thread to start */
- wait_for_completion(&(us->notify));
+ /* Take a reference to the host for the scanning thread and
+ * count it among all the threads we have launched. Then
+ * start it up. */
+ scsi_host_get(us_to_host(us));
+ atomic_inc(&total_threads);
+ wake_up_process(th);
return 0;
--
Matthew Dharm Home: [EMAIL PROTECTED]
Maintainer, Linux USB Mass Storage Driver
NYET! The evil stops here!
-- Pitr
User Friendly, 6/22/1998
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