drop scsi_register_blocked_host() in 2.5?

drop scsi_register_blocked_host() in 2.5?

[Douglas Gilbert]

Just doing some documentation and noticed these two functions:
   - scsi_register_blocked_host()
   - scsi_deregister_blocked_host()
that return void and do nothing. See scsi_lib.c around line 1344
for Eric's comment. These functions are exported and the
eata and u14-34f drivers call them.

Time for Christoph's razor?

Doug Gilbert

Re: drop scsi_register_blocked_host() in 2.5?

[Christoph Hellwig]

On Fri, Feb 21, 2003 at 12:24:37PM +1100, Douglas Gilbert wrote:
> Just doing some documentation and noticed these two functions:
>    - scsi_register_blocked_host()
>    - scsi_deregister_blocked_host()
> that return void and do nothing. See scsi_lib.c around line 1344
> for Eric's comment. These functions are exported and the
> eata and u14-34f drivers call them.
> 
> Time for Christoph's razor?

Well, it's not used for ages and there's not much reason to keep it
around.  So this gets my vote.

Re: drop scsi_register_blocked_host() in 2.5?

[Christoph Hellwig]

On Fri, Feb 21, 2003 at 12:24:37PM +1100, Douglas Gilbert wrote:
> Just doing some documentation and noticed these two functions:
>    - scsi_register_blocked_host()
>    - scsi_deregister_blocked_host()
> that return void and do nothing. See scsi_lib.c around line 1344
> for Eric's comment. These functions are exported and the
> eata and u14-34f drivers call them.
> 
> Time for Christoph's razor?

How does this patch look?


--- 1.36/drivers/scsi/scsi_error.c	Fri Feb 21 15:57:24 2003
+++ edited/drivers/scsi/scsi_error.c	Fri Feb 21 18:50:34 2003
@@ -15,33 +15,19 @@
  */
 
 #include <linux/module.h>
-
 #include <linux/sched.h>
 #include <linux/timer.h>
 #include <linux/string.h>
 #include <linux/slab.h>
-#include <linux/ioport.h>
 #include <linux/kernel.h>
-#include <linux/stat.h>
-#include <linux/blk.h>
 #include <linux/interrupt.h>
-#include <linux/delay.h>
+#include <linux/blkdev.h>
 #include <linux/smp_lock.h>
-#include <linux/completion.h>
-
-#define __KERNEL_SYSCALLS__
-
-#include <linux/unistd.h>
-
-#include <asm/system.h>
-#include <asm/irq.h>
-#include <asm/dma.h>
+#include <scsi/scsi_ioctl.h>
 
 #include "scsi.h"
 #include "hosts.h"
 
-#include <scsi/scsi_ioctl.h> /* grr */
-
 #ifdef DEBUG
 #define SENSE_TIMEOUT SCSI_TIMEOUT
 #else
@@ -111,8 +97,8 @@
  *    simple, really, especially compared to the old way of handling this
  *    crap.
  **/
-void scsi_add_timer(Scsi_Cmnd *scmd, int timeout, void (*complete)
-		    (Scsi_Cmnd *))
+void scsi_add_timer(struct scsi_cmnd *scmd, int timeout,
+		    void (*complete)(struct scsi_cmnd *))
 {
 
 	/*
@@ -120,10 +106,10 @@
 	 * first delete the timer.  The timer handling code gets rather
 	 * confused if we don't do this.
 	 */
-	if (scmd->eh_timeout.function != NULL) {
+	if (scmd->eh_timeout.function)
 		del_timer(&scmd->eh_timeout);
-	}
-	scmd->eh_timeout.data = (unsigned long) scmd;
+
+	scmd->eh_timeout.data = (unsigned long)scmd;
 	scmd->eh_timeout.expires = jiffies + timeout;
 	scmd->eh_timeout.function = (void (*)(unsigned long)) complete;
 
@@ -132,7 +118,6 @@
 					  scmd, timeout, complete));
 
 	add_timer(&scmd->eh_timeout);
-
 }
 
 /**
@@ -146,7 +131,7 @@
  *     1 if we were able to detach the timer.  0 if we blew it, and the
  *     timer function has already started to run.
  **/
-int scsi_delete_timer(Scsi_Cmnd *scmd)
+int scsi_delete_timer(struct scsi_cmnd *scmd)
 {
 	int rtn;
 
@@ -156,7 +141,7 @@
 					 " rtn: %d\n", __FUNCTION__,
 					 scmd, rtn));
 
-	scmd->eh_timeout.data = (unsigned long) NULL;
+	scmd->eh_timeout.data = (unsigned long)NULL;
 	scmd->eh_timeout.function = NULL;
 
 	return rtn;
@@ -172,7 +157,7 @@
  *     normal completion function determines that the timer has already
  *     fired, then it mustn't do anything.
  **/
-void scsi_times_out(Scsi_Cmnd *scmd)
+void scsi_times_out(struct scsi_cmnd *scmd)
 {
 	if (unlikely(!scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD))) {
 		panic("Error handler thread not present at %p %p %s %d",
@@ -195,7 +180,7 @@
  * Return value:
  *     0 when dev was taken offline by error recovery. 1 OK to proceed.
  **/
-int scsi_block_when_processing_errors(Scsi_Device *sdev)
+int scsi_block_when_processing_errors(struct scsi_device *sdev)
 {
 	wait_event(sdev->host->host_wait, (sdev->host->in_recovery == 0));
 
@@ -260,11 +245,10 @@
  * Return value:
  * 	SUCCESS or FAILED or NEEDS_RETRY
  **/
-static int scsi_check_sense(Scsi_Cmnd *scmd)
+static int scsi_check_sense(struct scsi_cmnd *scmd)
 {
-	if (!SCSI_SENSE_VALID(scmd)) {
+	if (!SCSI_SENSE_VALID(scmd))
 		return FAILED;
-	}
 	if (scmd->sense_buffer[2] & 0xe0)
 		return SUCCESS;
 
@@ -326,9 +310,8 @@
  *    don't allow for the possibility of retries here, and we are a lot
  *    more restrictive about what we consider acceptable.
  **/
-static int scsi_eh_completed_normally(Scsi_Cmnd *scmd)
+static int scsi_eh_completed_normally(struct scsi_cmnd *scmd)
 {
-
 	/*
 	 * first check the host byte, to see if there is anything in there
 	 * that would indicate what we need to do.
@@ -353,15 +336,15 @@
 		 */
 		return scsi_check_sense(scmd);
 	}
-	if (host_byte(scmd->result) != DID_OK) {
+	if (host_byte(scmd->result) != DID_OK)
 		return FAILED;
-	}
+
 	/*
 	 * next, check the message byte.
 	 */
-	if (msg_byte(scmd->result) != COMMAND_COMPLETE) {
+	if (msg_byte(scmd->result) != COMMAND_COMPLETE)
 		return FAILED;
-	}
+
 	/*
 	 * now, check the status byte to see if this indicates
 	 * anything special.
@@ -397,46 +380,38 @@
  *    for some action to complete on the device.  our only job is to
  *    record that it timed out, and to wake up the thread.
  **/
-static void scsi_eh_times_out(Scsi_Cmnd *scmd)
+static void scsi_eh_times_out(struct scsi_cmnd *scmd)
 {
 	scsi_eh_eflags_set(scmd, SCSI_EH_REC_TIMEOUT);
 	SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd:%p\n", __FUNCTION__,
 					  scmd));
 
-	if (scmd->device->host->eh_action != NULL)
+	if (scmd->device->host->eh_action)
 		up(scmd->device->host->eh_action);
-	else
-		printk("%s: eh_action NULL\n", __FUNCTION__);
 }
 
 /**
  * scsi_eh_done - Completion function for error handling.
  * @scmd:	Cmd that is done.
  **/
-static void scsi_eh_done(Scsi_Cmnd *scmd)
+static void scsi_eh_done(struct scsi_cmnd *scmd)
 {
-	int     rtn;
-
 	/*
 	 * if the timeout handler is already running, then just set the
 	 * flag which says we finished late, and return.  we have no
 	 * way of stopping the timeout handler from running, so we must
 	 * always defer to it.
 	 */
-	rtn = del_timer(&scmd->eh_timeout);
-	if (!rtn) {
-		return;
-	}
+	if (del_timer(&scmd->eh_timeout)) {
+		scmd->request->rq_status = RQ_SCSI_DONE;
+		scmd->owner = SCSI_OWNER_ERROR_HANDLER;
 
-	scmd->request->rq_status = RQ_SCSI_DONE;
-
-	scmd->owner = SCSI_OWNER_ERROR_HANDLER;
+		SCSI_LOG_ERROR_RECOVERY(3, printk("%s scmd: %p result: %x\n",
+					   __FUNCTION__, scmd, scmd->result));
 
-	SCSI_LOG_ERROR_RECOVERY(3, printk("%s scmd: %p result: %x\n",
-					  __FUNCTION__, scmd, scmd->result));
-
-	if (scmd->device->host->eh_action != NULL)
-		up(scmd->device->host->eh_action);
+		if (scmd->device->host->eh_action)
+			up(scmd->device->host->eh_action);
+	}
 }
 
 /**
@@ -451,10 +426,10 @@
  * Return value:
  *    SUCCESS or FAILED or NEEDS_RETRY
  **/
-static int scsi_send_eh_cmnd(Scsi_Cmnd *scmd, int timeout)
+static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, int timeout)
 {
-	unsigned long flags;
 	struct Scsi_Host *host = scmd->device->host;
+	unsigned long flags;
 	int rtn = SUCCESS;
 
 	ASSERT_LOCK(host->host_lock, 0);
@@ -567,32 +542,33 @@
  *    that we obtain it on our own. This function will *not* return until
  *    the command either times out, or it completes.
  **/
-static int scsi_request_sense(Scsi_Cmnd *scmd)
+static int scsi_request_sense(struct scsi_cmnd *scmd)
 {
 	static unsigned char generic_sense[6] =
 	{REQUEST_SENSE, 0, 0, 0, 255, 0};
-	unsigned char scsi_result0[256], *scsi_result = NULL;
+	unsigned char scsi_result0[256], *scsi_result = &scsi_result0[0];
 	int saved_result;
 	int rtn;
 
-	memcpy((void *) scmd->cmnd, (void *) generic_sense,
-	       sizeof(generic_sense));
-
-	scsi_result = (!scmd->device->host->hostt->unchecked_isa_dma)
-	    ? &scsi_result0[0] : kmalloc(512, GFP_ATOMIC | GFP_DMA);
+	memcpy(scmd->cmnd, generic_sense, sizeof(generic_sense));
 
-	if (scsi_result == NULL) {
-		printk("%s: cannot allocate scsi_result.\n", __FUNCTION__);
-		return FAILED;
+	if (scmd->device->host->hostt->unchecked_isa_dma) {
+		scsi_result = kmalloc(512, GFP_ATOMIC | __GFP_DMA);
+		if (unlikely(!scsi_result)) {
+			printk(KERN_ERR "%s: cannot allocate scsi_result.\n",
+					__FUNCTION__);
+			return FAILED;
+		}
 	}
+
 	/*
 	 * zero the sense buffer.  some host adapters automatically always
 	 * request sense, so it is not a good idea that
 	 * scmd->request_buffer and scmd->sense_buffer point to the same
 	 * address (db).  0 is not a valid sense code. 
 	 */
-	memset((void *) scmd->sense_buffer, 0, sizeof(scmd->sense_buffer));
-	memset((void *) scsi_result, 0, 256);
+	memset(scmd->sense_buffer, 0, sizeof(scmd->sense_buffer));
+	memset(scsi_result, 0, 256);
 
 	saved_result = scmd->result;
 	scmd->request_buffer = scsi_result;
@@ -605,12 +581,12 @@
 	rtn = scsi_send_eh_cmnd(scmd, SENSE_TIMEOUT);
 
 	/* last chance to have valid sense data */
-	if (!SCSI_SENSE_VALID(scmd))
-		memcpy((void *) scmd->sense_buffer,
-		       scmd->request_buffer,
-		       sizeof(scmd->sense_buffer));
+	if (!SCSI_SENSE_VALID(scmd)) {
+		memcpy(scmd->sense_buffer, scmd->request_buffer,
+				sizeof(scmd->sense_buffer));
+	}
 
-	if (scsi_result != &scsi_result0[0] && scsi_result != NULL)
+	if (scsi_result != &scsi_result0[0])
 		kfree(scsi_result);
 
 	/*
@@ -619,10 +595,6 @@
 	 */
 	scsi_setup_cmd_retry(scmd);
 	scmd->result = saved_result;
-
-	/*
-	 * hey, we are done.  let's look to see what happened.
-	 */
 	return rtn;
 }
 
@@ -634,7 +606,7 @@
  *    This function will *not* return until the command either times out,
  *    or it completes.
  **/
-static int scsi_eh_retry_cmd(Scsi_Cmnd *scmd)
+static int scsi_eh_retry_cmd(struct scsi_cmnd *scmd)
 {
 	int rtn = SUCCESS;
 
@@ -660,11 +632,12 @@
  *    keep a list of pending commands for final completion, and once we
  *    are ready to leave error handling we handle completion for real.
  **/
-static void scsi_eh_finish_cmd(Scsi_Cmnd *scmd,
-			       struct list_head *done_q )
+static void scsi_eh_finish_cmd(struct scsi_cmnd *scmd,
+			       struct list_head *done_q)
 {
 	scmd->device->host->host_failed--;
 	scmd->state = SCSI_STATE_BHQUEUE;
+
 	scsi_eh_eflags_clr_all(scmd);
 
 	/*
@@ -672,7 +645,6 @@
 	 * things.
 	 */
 	scsi_setup_cmd_retry(scmd);
-
 	list_move_tail(&scmd->eh_entry, done_q);
 }
 
@@ -685,7 +657,6 @@
  *    See if we need to request sense information.  if so, then get it
  *    now, so we have a better idea of what to do.  
  *
- *
  * Notes:
  *    This has the unfortunate side effect that if a shost adapter does
  *    not automatically request sense information, that we end up shutting
@@ -696,13 +667,15 @@
  *    this.
  *
  *    In 2.5 this capability will be going away.
+ *
+ *    Really?  --hch
  **/
 static int scsi_eh_get_sense(struct list_head *work_q,
 			     struct list_head *done_q)
 {
-	int rtn;
 	struct list_head *lh, *lh_sf;
-	Scsi_Cmnd *scmd;
+	struct scsi_cmnd *scmd;
+	int rtn;
 
 	list_for_each_safe(lh, lh_sf, work_q) {
 		scmd = list_entry(lh, struct scsi_cmnd, eh_entry);
@@ -766,14 +739,14 @@
  *    they can provide this facility themselves.  helper functions in
  *    scsi_error.c can be supplied to make this easier to do.
  **/
-static int scsi_try_to_abort_cmd(Scsi_Cmnd *scmd)
+static int scsi_try_to_abort_cmd(struct scsi_cmnd *scmd)
 {
-	int rtn = FAILED;
 	unsigned long flags;
+	int rtn = FAILED;
 
-	if (scmd->device->host->hostt->eh_abort_handler == NULL) {
+	if (!scmd->device->host->hostt->eh_abort_handler)
 		return rtn;
-	}
+
 	/*
 	 * scsi_done was called just after the command timed out and before
 	 * we had a chance to process it. (db)
@@ -786,6 +759,7 @@
 	spin_lock_irqsave(scmd->device->host->host_lock, flags);
 	rtn = scmd->device->host->hostt->eh_abort_handler(scmd);
 	spin_unlock_irqrestore(scmd->device->host->host_lock, flags);
+
 	return rtn;
 }
 
@@ -796,22 +770,19 @@
  * Return value:
  *    0 - Device is ready. 1 - Device NOT ready.
  **/
-static int scsi_eh_tur(Scsi_Cmnd *scmd)
+static int scsi_eh_tur(struct scsi_cmnd *scmd)
 {
-	static unsigned char tur_command[6] =
-	{TEST_UNIT_READY, 0, 0, 0, 0, 0};
-	int rtn;
-	int retry_cnt = 1;
+	static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0};
+	int retry_cnt = 1, rtn;
 
 retry_tur:
-	memcpy((void *) scmd->cmnd, (void *) tur_command,
-	       sizeof(tur_command));
+	memcpy(scmd->cmnd, tur_command, sizeof(tur_command));
 
 	/*
 	 * zero the sense buffer.  the scsi spec mandates that any
 	 * untransferred sense data should be interpreted as being zero.
 	 */
-	memset((void *) scmd->sense_buffer, 0, sizeof(scmd->sense_buffer));
+	memset(scmd->sense_buffer, 0, sizeof(scmd->sense_buffer));
 
 	scmd->request_buffer = NULL;
 	scmd->request_bufflen = 0;
@@ -856,9 +827,9 @@
 static int scsi_eh_abort_cmds(struct list_head *work_q,
 			      struct list_head *done_q)
 {
-	int rtn;
 	struct list_head *lh, *lh_sf;
 	struct scsi_cmnd *scmd;
+	int rtn;
 
 	list_for_each_safe(lh, lh_sf, work_q) {
 		scmd = list_entry(lh, struct scsi_cmnd, eh_entry);
@@ -895,14 +866,14 @@
  *    timer on it, and set the host back to a consistent state prior to
  *    returning.
  **/
-static int scsi_try_bus_device_reset(Scsi_Cmnd *scmd)
+static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd)
 {
 	unsigned long flags;
 	int rtn = FAILED;
 
-	if (scmd->device->host->hostt->eh_device_reset_handler == NULL) {
+	if (!scmd->device->host->hostt->eh_device_reset_handler)
 		return rtn;
-	}
+
 	scmd->owner = SCSI_OWNER_LOWLEVEL;
 
 	spin_lock_irqsave(scmd->device->host->host_lock, flags);
@@ -932,10 +903,10 @@
 				    struct list_head *work_q,
 				    struct list_head *done_q)
 {
-	int rtn;
 	struct list_head *lh, *lh_sf;
 	struct scsi_cmnd *scmd, *bdr_scmd;
 	struct scsi_device *sdev;
+	int rtn;
 
 	list_for_each_entry(sdev, &shost->my_devices, siblings) {
 		bdr_scmd = NULL;
@@ -980,18 +951,18 @@
  * scsi_try_bus_reset - ask host to perform a bus reset
  * @scmd:	SCSI cmd to send bus reset.
  **/
-static int scsi_try_bus_reset(Scsi_Cmnd *scmd)
+static int scsi_try_bus_reset(struct scsi_cmnd *scmd)
 {
+	struct scsi_device *sdev;
 	unsigned long flags;
 	int rtn;
-	Scsi_Device *sdev;
 
 	SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Bus RST\n",
 					  __FUNCTION__));
 	scmd->owner = SCSI_OWNER_LOWLEVEL;
 	scmd->serial_number_at_timeout = scmd->serial_number;
 
-	if (scmd->device->host->hostt->eh_bus_reset_handler == NULL)
+	if (!scmd->device->host->hostt->eh_bus_reset_handler)
 		return FAILED;
 
 	spin_lock_irqsave(scmd->device->host->host_lock, flags);
@@ -1017,18 +988,18 @@
  * scsi_try_host_reset - ask host adapter to reset itself
  * @scmd:	SCSI cmd to send hsot reset.
  **/
-static int scsi_try_host_reset(Scsi_Cmnd *scmd)
+static int scsi_try_host_reset(struct scsi_cmnd *scmd)
 {
+	struct scsi_device *sdev;
 	unsigned long flags;
 	int rtn;
-	 Scsi_Device *sdev;
 
 	SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Host RST\n",
 					  __FUNCTION__));
 	scmd->owner = SCSI_OWNER_LOWLEVEL;
 	scmd->serial_number_at_timeout = scmd->serial_number;
 
-	if (scmd->device->host->hostt->eh_host_reset_handler == NULL)
+	if (!scmd->device->host->hostt->eh_host_reset_handler)
 		return FAILED;
 
 	spin_lock_irqsave(scmd->device->host->host_lock, flags);
@@ -1059,11 +1030,11 @@
 			     struct list_head *work_q,
 			     struct list_head *done_q)
 {
-	int rtn;
 	struct list_head *lh, *lh_sf;
-	Scsi_Cmnd *scmd;
-	Scsi_Cmnd *chan_scmd;
+	struct scsi_cmnd *scmd;
+	struct scsi_cmnd *chan_scmd;
 	unsigned int channel;
+	int rtn;
 
 	/*
 	 * we really want to loop over the various channels, and do this on
@@ -1121,7 +1092,7 @@
 {
 	int rtn;
 	struct list_head *lh, *lh_sf;
-	Scsi_Cmnd *scmd;
+	struct scsi_cmnd *scmd;
 
 	if (!list_empty(work_q)) {
 		scmd = list_entry(work_q->next,
@@ -1156,7 +1127,7 @@
 				  struct list_head *done_q)
 {
 	struct list_head *lh, *lh_sf;
-	Scsi_Cmnd *scmd;
+	struct scsi_cmnd *scmd;
 
 	list_for_each_safe(lh, lh_sf, work_q) {
 		scmd = list_entry(lh, struct scsi_cmnd, eh_entry);
@@ -1183,12 +1154,12 @@
  * @sem:	semphore to signal
  *
  **/
-static
-void scsi_sleep_done(struct semaphore *sem)
+static void scsi_sleep_done(unsigned long data)
 {
-	if (sem != NULL) {
+	struct semaphore *sem = (struct semaphore *)data;
+
+	if (sem)
 		up(sem);
-	}
 }
 
 /**
@@ -1202,9 +1173,9 @@
 	struct timer_list timer;
 
 	init_timer(&timer);
-	timer.data = (unsigned long) &sem;
+	timer.data = (unsigned long)&sem;
 	timer.expires = jiffies + timeout;
-	timer.function = (void (*)(unsigned long)) scsi_sleep_done;
+	timer.function = (void (*)(unsigned long))scsi_sleep_done;
 
 	SCSI_LOG_ERROR_RECOVERY(5, printk("sleeping for timer tics %d\n",
 					  timeout));
@@ -1229,7 +1200,7 @@
  *    doesn't require the error handler read (i.e. we don't need to
  *    abort/reset), then this function should return SUCCESS.
  **/
-int scsi_decide_disposition(Scsi_Cmnd *scmd)
+int scsi_decide_disposition(struct scsi_cmnd *scmd)
 {
 	int rtn;
 
@@ -1429,7 +1400,7 @@
 {
 	struct scsi_request *sreq = scsi_allocate_request(sdev);
 
-	if (sreq == NULL) {
+	if (unlikely(!sreq)) {
 		printk(KERN_ERR "%s: request allocate failed,"
 		       "prevent media removal cmd not sent", __FUNCTION__);
 		return;
@@ -1463,7 +1434,7 @@
  **/
 static void scsi_restart_operations(struct Scsi_Host *shost)
 {
-	Scsi_Device *sdev;
+	struct scsi_device *sdev;
 	unsigned long flags;
 
 	ASSERT_LOCK(shost->host_lock, 0);
@@ -1533,7 +1504,7 @@
 static void scsi_eh_flush_done_q(struct list_head *done_q)
 {
 	struct list_head *lh, *lh_sf;
-	Scsi_Cmnd *scmd;
+	struct scsi_cmnd *scmd;
 
 	list_for_each_safe(lh, lh_sf, done_q) {
 		scmd = list_entry(lh, struct scsi_cmnd, eh_entry);
@@ -1674,11 +1645,10 @@
 		 * what we need to do to get it up and online again (if we can).
 		 * If we fail, we end up taking the thing offline.
 		 */
-		if (shost->hostt->eh_strategy_handler != NULL) {
+		if (shost->hostt->eh_strategy_handler) 
 			rtn = shost->hostt->eh_strategy_handler(shost);
-		} else {
+		else
 			scsi_unjam_host(shost);
-		}
 
 		shost->eh_active = 0;
 
@@ -1719,45 +1689,8 @@
 	complete_and_exit(shost->eh_notify, 0);
 }
 
-/**
- * scsi_new_reset - Send reset to a bus or device at any phase.
- * @scmd:	Cmd to send reset with (usually a dummy)
- * @flag:	Reset type.
- *
- * Description:
- *    This is used by the SCSI Generic driver to provide Bus/Device reset
- *    capability.
- *
- * Return value:
- *    SUCCESS/FAILED.
- **/
-static int scsi_new_reset(Scsi_Cmnd *scmd, int flag)
-{
-	int rtn;
-
-	switch(flag) {
-	case SCSI_TRY_RESET_DEVICE:
-		rtn = scsi_try_bus_device_reset(scmd);
-		if (rtn == SUCCESS)
-			break;
-		/* FALLTHROUGH */
-	case SCSI_TRY_RESET_BUS:
-		rtn = scsi_try_bus_reset(scmd);
-		if (rtn == SUCCESS)
-			break;
-		/* FALLTHROUGH */
-	case SCSI_TRY_RESET_HOST:
-		rtn = scsi_try_host_reset(scmd);
-		break;
-	default:
-		rtn = FAILED;
-	}
-
-	return rtn;
-}
-
 static void
-scsi_reset_provider_done_command(Scsi_Cmnd *SCpnt)
+scsi_reset_provider_done_command(struct scsi_cmnd *scmd)
 {
 }
 
@@ -1775,47 +1708,63 @@
  *		Bus/Device reset capability.
  */
 int
-scsi_reset_provider(Scsi_Device *dev, int flag)
+scsi_reset_provider(struct scsi_device *dev, int flag)
 {
-	struct scsi_cmnd *SCpnt = scsi_get_command(dev, GFP_KERNEL);
+	struct scsi_cmnd *scmd = scsi_get_command(dev, GFP_KERNEL);
 	struct request req;
 	int rtn;
 
-	SCpnt->request = &req;
-	memset(&SCpnt->eh_timeout, 0, sizeof(SCpnt->eh_timeout));
-	SCpnt->request->rq_status      	= RQ_SCSI_BUSY;
-	SCpnt->state                   	= SCSI_STATE_INITIALIZING;
-	SCpnt->owner	     		= SCSI_OWNER_MIDLEVEL;
+	scmd->request = &req;
+	memset(&scmd->eh_timeout, 0, sizeof(scmd->eh_timeout));
+	scmd->request->rq_status      	= RQ_SCSI_BUSY;
+	scmd->state                   	= SCSI_STATE_INITIALIZING;
+	scmd->owner	     		= SCSI_OWNER_MIDLEVEL;
     
-	memset(&SCpnt->cmnd, '\0', sizeof(SCpnt->cmnd));
+	memset(&scmd->cmnd, '\0', sizeof(scmd->cmnd));
     
-	SCpnt->scsi_done		= scsi_reset_provider_done_command;
-	SCpnt->done			= NULL;
-	SCpnt->reset_chain		= NULL;
+	scmd->scsi_done		= scsi_reset_provider_done_command;
+	scmd->done			= NULL;
+	scmd->reset_chain		= NULL;
         
-	SCpnt->buffer			= NULL;
-	SCpnt->bufflen			= 0;
-	SCpnt->request_buffer		= NULL;
-	SCpnt->request_bufflen		= 0;
-
-	SCpnt->internal_timeout		= NORMAL_TIMEOUT;
-	SCpnt->abort_reason		= DID_ABORT;
-
-	SCpnt->cmd_len			= 0;
-
-	SCpnt->sc_data_direction	= SCSI_DATA_UNKNOWN;
-	SCpnt->sc_request		= NULL;
-	SCpnt->sc_magic			= SCSI_CMND_MAGIC;
+	scmd->buffer			= NULL;
+	scmd->bufflen			= 0;
+	scmd->request_buffer		= NULL;
+	scmd->request_bufflen		= 0;
+
+	scmd->internal_timeout		= NORMAL_TIMEOUT;
+	scmd->abort_reason		= DID_ABORT;
+
+	scmd->cmd_len			= 0;
+
+	scmd->sc_data_direction	= SCSI_DATA_UNKNOWN;
+	scmd->sc_request		= NULL;
+	scmd->sc_magic			= SCSI_CMND_MAGIC;
 
 	/*
 	 * Sometimes the command can get back into the timer chain,
 	 * so use the pid as an identifier.
 	 */
-	SCpnt->pid			= 0;
+	scmd->pid			= 0;
 
-	rtn = scsi_new_reset(SCpnt, flag);
+	switch (flag) {
+	case SCSI_TRY_RESET_DEVICE:
+		rtn = scsi_try_bus_device_reset(scmd);
+		if (rtn == SUCCESS)
+			break;
+		/* FALLTHROUGH */
+	case SCSI_TRY_RESET_BUS:
+		rtn = scsi_try_bus_reset(scmd);
+		if (rtn == SUCCESS)
+			break;
+		/* FALLTHROUGH */
+	case SCSI_TRY_RESET_HOST:
+		rtn = scsi_try_host_reset(scmd);
+		break;
+	default:
+		rtn = FAILED;
+	}
 
-	scsi_delete_timer(SCpnt);
-	scsi_put_command(SCpnt);
+	scsi_delete_timer(scmd);
+	scsi_put_command(scmd);
 	return rtn;
 }

Re: drop scsi_register_blocked_host() in 2.5?

[Christoph Hellwig]

On Fri, Feb 21, 2003 at 11:50:31PM +0100, Christoph Hellwig wrote:
> On Fri, Feb 21, 2003 at 12:24:37PM +1100, Douglas Gilbert wrote:
> > Just doing some documentation and noticed these two functions:
> >    - scsi_register_blocked_host()
> >    - scsi_deregister_blocked_host()
> > that return void and do nothing. See scsi_lib.c around line 1344
> > for Eric's comment. These functions are exported and the
> > eata and u14-34f drivers call them.
> > 
> > Time for Christoph's razor?
> 
> How does this patch look?

Probably not good as I attached the wrong patch..


--- 1.27/drivers/scsi/eata.c	Tue Feb 11 15:51:57 2003
+++ edited/drivers/scsi/eata.c	Fri Feb 21 23:27:14 2003
@@ -1228,7 +1228,6 @@
       sh[j]->unchecked_isa_dma = FALSE;
    else {
       unsigned long flags;
-      scsi_register_blocked_host(sh[j]);
       sh[j]->unchecked_isa_dma = TRUE;
 
       flags=claim_dma_lock();
@@ -2352,8 +2351,6 @@
 
    if (sh[j] == NULL) panic("%s: release, invalid Scsi_Host pointer.\n",
                             driver_name);
-
-   if(sh[j]->unchecked_isa_dma) scsi_deregister_blocked_host(sh[j]);
 
    for (i = 0; i < sh[j]->can_queue; i++)
       if ((&HD(j)->cp[i])->sglist) kfree((&HD(j)->cp[i])->sglist);
--- 1.55/drivers/scsi/hosts.h	Fri Feb 21 15:57:24 2003
+++ edited/drivers/scsi/hosts.h	Fri Feb 21 23:27:46 2003
@@ -515,8 +515,6 @@
 extern void scsi_unblock_requests(struct Scsi_Host *);
 extern void scsi_block_requests(struct Scsi_Host *);
 extern void scsi_report_bus_reset(struct Scsi_Host *, int);
-extern void scsi_register_blocked_host(struct Scsi_Host *);
-extern void scsi_deregister_blocked_host(struct Scsi_Host *);
 
 static inline void scsi_assign_lock(struct Scsi_Host *shost, spinlock_t *lock)
 {
--- 1.71/drivers/scsi/scsi_lib.c	Fri Feb 21 15:57:25 2003
+++ edited/drivers/scsi/scsi_lib.c	Fri Feb 21 23:27:58 2003
@@ -1340,23 +1340,6 @@
 	}
 }
 
-/*
- * FIXME(eric) - these are empty stubs for the moment.  I need to re-implement
- * host blocking from scratch. The theory is that hosts that wish to block
- * will register/deregister using these functions instead of the old way
- * of setting the wish_block flag.
- *
- * The details of the implementation remain to be settled, however the
- * stubs are here now so that the actual drivers will properly compile.
- */
-void scsi_register_blocked_host(struct Scsi_Host * shost)
-{
-}
-
-void scsi_deregister_blocked_host(struct Scsi_Host * shost)
-{
-}
-
 int __init scsi_init_queue(void)
 {
 	int i;
--- 1.27/drivers/scsi/scsi_syms.c	Mon Feb 10 23:25:47 2003
+++ edited/drivers/scsi/scsi_syms.c	Fri Feb 21 23:27:39 2003
@@ -74,8 +74,6 @@
 
 EXPORT_SYMBOL(scsi_io_completion);
 
-EXPORT_SYMBOL(scsi_register_blocked_host);
-EXPORT_SYMBOL(scsi_deregister_blocked_host);
 EXPORT_SYMBOL(scsi_slave_attach);
 EXPORT_SYMBOL(scsi_slave_detach);
 EXPORT_SYMBOL(scsi_device_get);
--- 1.23/drivers/scsi/u14-34f.c	Wed Feb 12 11:56:04 2003
+++ edited/drivers/scsi/u14-34f.c	Fri Feb 21 23:27:28 2003
@@ -905,7 +905,6 @@
       }
    else {
       unsigned long flags;
-      scsi_register_blocked_host(sh[j]);
       sh[j]->unchecked_isa_dma = TRUE;
 
       flags=claim_dma_lock();
@@ -1910,8 +1909,6 @@
 
    if (sh[j] == NULL) panic("%s: release, invalid Scsi_Host pointer.\n",
                             driver_name);
-
-   if(sh[j]->unchecked_isa_dma) scsi_deregister_blocked_host(sh[j]);
 
    for (i = 0; i < sh[j]->can_queue; i++)
       if ((&HD(j)->cp[i])->sglist) kfree((&HD(j)->cp[i])->sglist);

RE: drop scsi_register_blocked_host() in 2.5?

[Ballabio_Dario]

This means giving up forever to support multiple isa scsi hba's.
The aim of these routines (left unimplemented by Eric during the 2.3
development cycle)
was to allow multiple isa hba working at the same time, but being active
one at a time. If you try to do heavy i/o on a system with multiple u14-34f
or isa eata boards (I have not tested aha1542 but it is probably the same)
it crashes immediately due to data corruption at the isa bus level.
Using a 2.2 kernel the same system works perfectly.


-db


-----Original Message-----
From: Christoph Hellwig [mailto:hch@infradead.org]
Sent: Friday, February 21, 2003 8:59 PM
To: Douglas Gilbert
Cc: linux-scsi@vger.kernel.org
Subject: Re: drop scsi_register_blocked_host() in 2.5?


On Fri, Feb 21, 2003 at 12:24:37PM +1100, Douglas Gilbert wrote:
> Just doing some documentation and noticed these two functions:
>    - scsi_register_blocked_host()
>    - scsi_deregister_blocked_host()
> that return void and do nothing. See scsi_lib.c around line 1344
> for Eric's comment. These functions are exported and the
> eata and u14-34f drivers call them.
> 
> Time for Christoph's razor?

Well, it's not used for ages and there's not much reason to keep it
around.  So this gets my vote.

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Re: drop scsi_register_blocked_host() in 2.5?

[Christoph Hellwig]

On Mon, Feb 24, 2003 at 03:32:09AM -0500, Ballabio_Dario@emc.com wrote:
> This means giving up forever to support multiple isa scsi hba's.
> The aim of these routines (left unimplemented by Eric during the 2.3
> development cycle)
> was to allow multiple isa hba working at the same time, but being active
> one at a time. If you try to do heavy i/o on a system with multiple u14-34f
> or isa eata boards (I have not tested aha1542 but it is probably the same)
> it crashes immediately due to data corruption at the isa bus level.
> Using a 2.2 kernel the same system works perfectly.

The stubs won't help you to reach that goal.  Feel free to bring them back
once you have an actual implementation.

Re: drop scsi_register_blocked_host() in 2.5?

[James Bottomley]

On Mon, 2003-02-24 at 15:17, Christoph Hellwig wrote:
> On Mon, Feb 24, 2003 at 03:32:09AM -0500, Ballabio_Dario@emc.com wrote:
> > This means giving up forever to support multiple isa scsi hba's.
> > The aim of these routines (left unimplemented by Eric during the 2.3
> > development cycle)
> > was to allow multiple isa hba working at the same time, but being active
> > one at a time. If you try to do heavy i/o on a system with multiple u14-34f
> > or isa eata boards (I have not tested aha1542 but it is probably the same)
> > it crashes immediately due to data corruption at the isa bus level.
> > Using a 2.2 kernel the same system works perfectly.
> 
> The stubs won't help you to reach that goal.  Feel free to bring them back
> once you have an actual implementation.

Not for this reason.  It's fundamentally not SCSIs job to solve bus
contention issues like this.  Most busses employ arbitration mechanisms
for this very reason.  If the bus doesn't that would be grounds for not
using >1 HBA per bus.

The host blocked API may play a useful role for FC events such as loop
down and LIP, but I don't think register_host_blocked serves any purpose
for this.

James