Commit 1aa8fab2 authored by Matthew Wilcox's avatar Matthew Wilcox Committed by James Bottomley
Browse files

[SCSI] Make scsi_scan_host work for drivers which find their own targets 



If a driver can find its own targets, it can now fill in scan_finished and
(optionally) scan_start in the scsi_host_template.  Then, when it calls
scsi_scan_host(), it will be called back (from a thread if asynchronous
discovery is enabled), first to start the scan, and then at intervals to
check if the scan is completed.

Also make scsi_prep_async_scan and scsi_finish_async_scan static.

Signed-off-by: default avatarMatthew Wilcox <matthew@wil.cx>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@SteelEye.com>
parent 93b45af5

drivers/scsi/scsi_scan.c

+20 −7
Original line number Diff line number Diff line
@@ -1642,7 +1642,7 @@ static void scsi_sysfs_add_devices(struct Scsi_Host *shost) 
 * that other asynchronous scans started after this one won't affect the

 * ordering of the discovered devices.

 */

struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)

static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)

{

	struct async_scan_data *data;
@@ -1686,7 +1686,7 @@ struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) 
 * This function announces all the devices it has found to the rest

 * of the system.

 */

void scsi_finish_async_scan(struct async_scan_data *data)

static void scsi_finish_async_scan(struct async_scan_data *data)

{

	struct Scsi_Host *shost;
@@ -1719,12 +1719,25 @@ void scsi_finish_async_scan(struct async_scan_data *data) 
	kfree(data);

}



static int do_scan_async(void *_data)

static void do_scsi_scan_host(struct Scsi_Host *shost)

{

	struct async_scan_data *data = _data;

	scsi_scan_host_selected(data->shost, SCAN_WILD_CARD, SCAN_WILD_CARD,

	if (shost->hostt->scan_finished) {

		unsigned long start = jiffies;

		if (shost->hostt->scan_start)

			shost->hostt->scan_start(shost);



		while (!shost->hostt->scan_finished(shost, jiffies - start))

			msleep(10);

	} else {

		scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,

				SCAN_WILD_CARD, 0);

	}

}



static int do_scan_async(void *_data)

{

	struct async_scan_data *data = _data;

	do_scsi_scan_host(data->shost);

	scsi_finish_async_scan(data);

	return 0;

}
@@ -1742,10 +1755,10 @@ void scsi_scan_host(struct Scsi_Host *shost) 


	data = scsi_prep_async_scan(shost);

	if (!data) {

		scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,

					SCAN_WILD_CARD, 0);

		do_scsi_scan_host(shost);

		return;

	}



	kthread_run(do_scan_async, data, "scsi_scan_%d", shost->host_no);

}

EXPORT_SYMBOL(scsi_scan_host);

include/scsi/scsi_host.h

+18 −0
Original line number Diff line number Diff line
@@ -240,6 +240,24 @@ struct scsi_host_template { 
	 */

	void (* target_destroy)(struct scsi_target *);



	/*

	 * If a host has the ability to discover targets on its own instead

	 * of scanning the entire bus, it can fill in this function and

	 * call scsi_scan_host().  This function will be called periodically

	 * until it returns 1 with the scsi_host and the elapsed time of

	 * the scan in jiffies.

	 *

	 * Status: OPTIONAL

	 */

	int (* scan_finished)(struct Scsi_Host *, unsigned long);



	/*

	 * If the host wants to be called before the scan starts, but

	 * after the midlayer has set up ready for the scan, it can fill

	 * in this function.

	 */

	void (* scan_start)(struct Scsi_Host *);



	/*

	 * fill in this function to allow the queue depth of this host

	 * to be changeable (on a per device basis).  returns either

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