[PATCH, RFC] sym2: remove unkown data direction handling

[PATCH, RFC] sym2: remove unkown data direction handling

[Christoph Hellwig]

since 2.3 the LLDD gets the data direction passed down, so we don't
need to kludge around an unknown data direction anymore.  I've added
a BUG when we get an unkown data direction neverless, and it seems to
survive so far under low load.


--- 1.7/drivers/scsi/sym53c8xx_2/sym_fw.c	2004-09-13 11:10:31 +02:00
+++ edited/drivers/scsi/sym53c8xx_2/sym_fw.c	2004-10-26 14:35:24 +02:00
@@ -70,9 +70,6 @@
 };
 static struct sym_fwb_ofs sym_fw1b_ofs = {
 	SYM_GEN_FW_B(struct SYM_FWB_SCR)
-#ifdef SYM_OPT_HANDLE_DIR_UNKNOWN
-	SYM_GEN_B(struct SYM_FWB_SCR, data_io)
-#endif
 };
 static struct sym_fwz_ofs sym_fw1z_ofs = {
 	SYM_GEN_FW_Z(struct SYM_FWZ_SCR)
@@ -98,9 +95,6 @@
 };
 static struct sym_fwb_ofs sym_fw2b_ofs = {
 	SYM_GEN_FW_B(struct SYM_FWB_SCR)
-#ifdef SYM_OPT_HANDLE_DIR_UNKNOWN
-	SYM_GEN_B(struct SYM_FWB_SCR, data_io)
-#endif
 	SYM_GEN_B(struct SYM_FWB_SCR, start64)
 	SYM_GEN_B(struct SYM_FWB_SCR, pm_handle)
 };
===== drivers/scsi/sym53c8xx_2/sym_fw.h 1.3 vs edited =====
--- 1.3/drivers/scsi/sym53c8xx_2/sym_fw.h	2004-09-13 11:10:31 +02:00
+++ edited/drivers/scsi/sym53c8xx_2/sym_fw.h	2004-10-26 14:35:01 +02:00
@@ -92,9 +92,6 @@
 };
 struct sym_fwb_ofs {
 	SYM_GEN_FW_B(u_short)
-#ifdef SYM_OPT_HANDLE_DIR_UNKNOWN
-	SYM_GEN_B(u_short, data_io)
-#endif
 	SYM_GEN_B(u_short, start64)
 	SYM_GEN_B(u_short, pm_handle)
 };
@@ -111,9 +108,6 @@
 };
 struct sym_fwb_ba {
 	SYM_GEN_FW_B(u32)
-#ifdef SYM_OPT_HANDLE_DIR_UNKNOWN
-	SYM_GEN_B(u32, data_io)
-#endif
 	SYM_GEN_B(u32, start64);
 	SYM_GEN_B(u32, pm_handle);
 };
===== drivers/scsi/sym53c8xx_2/sym_fw1.h 1.6 vs edited =====
--- 1.6/drivers/scsi/sym53c8xx_2/sym_fw1.h	2004-09-13 11:10:31 +02:00
+++ edited/drivers/scsi/sym53c8xx_2/sym_fw1.h	2004-10-26 14:35:11 +02:00
@@ -197,12 +197,6 @@
 	u32 bad_status		[  7];
 	u32 wsr_ma_helper	[  4];
 
-#ifdef SYM_OPT_HANDLE_DIR_UNKNOWN
-	/* Unknown direction handling */
-	u32 data_io		[  2];
-	u32 data_io_com		[  8];
-	u32 data_io_out		[  7];
-#endif
 	/* Data area */
 	u32 zero		[  1];
 	u32 scratch		[  1];
@@ -1746,48 +1740,6 @@
 		offsetof (struct sym_ccb, phys.wresid),
 	SCR_JUMP,
 		PADDR_A (dispatch),
-
-#ifdef SYM_OPT_HANDLE_DIR_UNKNOWN
-}/*-------------------------< DATA_IO >--------------------------*/,{
-	/*
-	 *  We jump here if the data direction was unknown at the 
-	 *  time we had to queue the command to the scripts processor.
-	 *  Pointers had been set as follow in this situation:
-	 *    savep   -->   DATA_IO
-	 *    lastp   -->   start pointer when DATA_IN
-	 *    wlastp  -->   start pointer when DATA_OUT
-	 *  This script sets savep and lastp according to the 
-	 *  direction chosen by the target.
-	 */
-	SCR_JUMP ^ IFTRUE (WHEN (SCR_DATA_OUT)),
-		PADDR_B (data_io_out),
-}/*-------------------------< DATA_IO_COM >----------------------*/,{
-	/*
-	 *  Direction is DATA IN.
-	 */
-	SCR_COPY  (4),
-		HADDR_1 (ccb_head.lastp),
-		HADDR_1 (ccb_head.savep),
-	/*
-	 *  Jump to the SCRIPTS according to actual direction.
-	 */
-	SCR_COPY  (4),
-		HADDR_1 (ccb_head.savep),
-		RADDR_1 (temp),
-	SCR_RETURN,
-		0,
-}/*-------------------------< DATA_IO_OUT >----------------------*/,{
-	/*
-	 *  Direction is DATA OUT.
-	 */
-	SCR_REG_REG (HF_REG, SCR_AND, (~HF_DATA_IN)),
-		0,
-	SCR_COPY  (4),
-		HADDR_1 (ccb_head.wlastp),
-		HADDR_1 (ccb_head.lastp),
-	SCR_JUMP,
-		PADDR_B(data_io_com),
-#endif /* SYM_OPT_HANDLE_DIR_UNKNOWN */
 
 }/*-------------------------< ZERO >-----------------------------*/,{
 	SCR_DATA_ZERO,
===== drivers/scsi/sym53c8xx_2/sym_fw2.h 1.6 vs edited =====
--- 1.6/drivers/scsi/sym53c8xx_2/sym_fw2.h	2004-09-13 11:10:32 +02:00
+++ edited/drivers/scsi/sym53c8xx_2/sym_fw2.h	2004-10-26 14:35:21 +02:00
@@ -191,13 +191,6 @@
 	u32 pm_wsr_handle	[ 38];
 	u32 wsr_ma_helper	[  4];
 
-#ifdef SYM_OPT_HANDLE_DIR_UNKNOWN
-	/* Unknown direction handling */
-	u32 data_io		[  2];
-	u32 data_io_in		[  2];
-	u32 data_io_com		[  6];
-	u32 data_io_out		[  8];
-#endif
 	/* Data area */
 	u32 zero		[  1];
 	u32 scratch		[  1];
@@ -1837,51 +1830,6 @@
 		offsetof (struct sym_ccb, phys.wresid),
 	SCR_JUMP,
 		PADDR_A (dispatch),
-
-#ifdef SYM_OPT_HANDLE_DIR_UNKNOWN
-}/*-------------------------< DATA_IO >--------------------------*/,{
-	/*
-	 *  We jump here if the data direction was unknown at the 
-	 *  time we had to queue the command to the scripts processor.
-	 *  Pointers had been set as follow in this situation:
-	 *    savep   -->   DATA_IO
-	 *    lastp   -->   start pointer when DATA_IN
-	 *    wlastp  -->   start pointer when DATA_OUT
-	 *  This script sets savep and lastp according to the 
-	 *  direction chosen by the target.
-	 */
-	SCR_JUMP ^ IFTRUE (WHEN (SCR_DATA_OUT)),
-		PADDR_B (data_io_out),
-}/*-------------------------< DATA_IO_IN >-----------------------*/,{
-	/*
-	 *  Direction is DATA IN.
-	 */
-	SCR_LOAD_REL  (scratcha, 4),
-		offsetof (struct sym_ccb, phys.head.lastp),
-}/*-------------------------< DATA_IO_COM >----------------------*/,{
-	SCR_STORE_REL (scratcha, 4),
-		offsetof (struct sym_ccb, phys.head.savep),
-
-	/*
-	 *  Jump to the SCRIPTS according to actual direction.
-	 */
-	SCR_LOAD_REL  (temp, 4),
-		offsetof (struct sym_ccb, phys.head.savep),
-	SCR_RETURN,
-		0,
-}/*-------------------------< DATA_IO_OUT >----------------------*/,{
-	/*
-	 *  Direction is DATA OUT.
-	 */
-	SCR_REG_REG (HF_REG, SCR_AND, (~HF_DATA_IN)),
-		0,
-	SCR_LOAD_REL  (scratcha, 4),
-		offsetof (struct sym_ccb, phys.head.wlastp),
-	SCR_STORE_REL (scratcha, 4),
-		offsetof (struct sym_ccb, phys.head.lastp),
-	SCR_JUMP,
-		PADDR_B(data_io_com),
-#endif /* SYM_OPT_HANDLE_DIR_UNKNOWN */
 
 }/*-------------------------< ZERO >-----------------------------*/,{
 	SCR_DATA_ZERO,
===== drivers/scsi/sym53c8xx_2/sym_glue.h 1.23 vs edited =====
--- 1.23/drivers/scsi/sym53c8xx_2/sym_glue.h	2004-10-24 18:08:18 +02:00
+++ edited/drivers/scsi/sym53c8xx_2/sym_glue.h	2004-10-26 14:35:32 +02:00
@@ -74,7 +74,6 @@
  */
 #define	SYM_CONF_TIMER_INTERVAL		((HZ+1)/2)
 
-#define SYM_OPT_HANDLE_DIR_UNKNOWN
 #define SYM_OPT_HANDLE_DEVICE_QUEUEING
 #define SYM_OPT_LIMIT_COMMAND_REORDERING
 #define	SYM_OPT_ANNOUNCE_TRANSFER_RATE
===== drivers/scsi/sym53c8xx_2/sym_hipd.h 1.8 vs edited =====
--- 1.8/drivers/scsi/sym53c8xx_2/sym_hipd.h	2004-09-13 11:10:32 +02:00
+++ edited/drivers/scsi/sym53c8xx_2/sym_hipd.h	2004-11-02 12:10:53 +01:00
@@ -46,12 +46,6 @@
  *  They may be defined in platform specific headers, if they 
  *  are useful.
  *
- *    SYM_OPT_HANDLE_DIR_UNKNOWN
- *        When this option is set, the SCRIPTS used by the driver 
- *        are able to handle SCSI transfers with direction not 
- *        supplied by user.
- *        (set for Linux-2.0.X)
- *
  *    SYM_OPT_HANDLE_DEVICE_QUEUEING
  *        When this option is set, the driver will use a queue per 
  *        device and handle QUEUE FULL status requeuing internally.
@@ -62,7 +56,6 @@
  *        (set for Linux)
  */
 #if 0
-#define SYM_OPT_HANDLE_DIR_UNKNOWN
 #define SYM_OPT_HANDLE_DEVICE_QUEUEING
 #define SYM_OPT_LIMIT_COMMAND_REORDERING
 #endif
@@ -663,9 +656,6 @@
 	 */
 	u32	savep;		/* Jump address to saved data pointer	*/
 	u32	lastp;		/* SCRIPTS address at end of data	*/
-#ifdef	SYM_OPT_HANDLE_DIR_UNKNOWN
-	u32	wlastp;
-#endif
 
 	/*
 	 *  Status fields.
@@ -810,9 +800,6 @@
 		link_ccbq;	/* Link to free/busy CCB queue	*/
 	u32	startp;		/* Initial data pointer		*/
 	u32	goalp;		/* Expected last data pointer	*/
-#ifdef	SYM_OPT_HANDLE_DIR_UNKNOWN
-	u32	wgoalp;
-#endif
 	int	ext_sg;		/* Extreme data pointer, used	*/
 	int	ext_ofs;	/*  to calculate the residual.	*/
 #ifdef SYM_OPT_HANDLE_DEVICE_QUEUEING
@@ -828,11 +815,7 @@
 
 #define CCB_BA(cp,lbl)	(cp->ccb_ba + offsetof(struct sym_ccb, lbl))
 
-#ifdef	SYM_OPT_HANDLE_DIR_UNKNOWN
-#define	sym_goalp(cp) ((cp->host_flags & HF_DATA_IN) ? cp->goalp : cp->wgoalp)
-#else
 #define	sym_goalp(cp) (cp->goalp)
-#endif
 
 /*
  *  Host Control Block
@@ -1192,34 +1175,22 @@
 	/*
 	 *  Set the data pointer.
 	 */
-	switch(dir) {
-#ifdef	SYM_OPT_HANDLE_DIR_UNKNOWN
-	case CAM_DIR_UNKNOWN:
-#endif
+	switch (dir) {
 	case CAM_DIR_OUT:
 		goalp = SCRIPTA_BA (np, data_out2) + 8;
 		lastp = goalp - 8 - (cp->segments * (2*4));
-#ifdef	SYM_OPT_HANDLE_DIR_UNKNOWN
-		cp->wgoalp = cpu_to_scr(goalp);
-		if (dir != CAM_DIR_UNKNOWN)
-			break;
-		cp->phys.head.wlastp = cpu_to_scr(lastp);
-		/* fall through */
-#else
 		break;
-#endif
 	case CAM_DIR_IN:
 		cp->host_flags |= HF_DATA_IN;
 		goalp = SCRIPTA_BA (np, data_in2) + 8;
 		lastp = goalp - 8 - (cp->segments * (2*4));
 		break;
 	case CAM_DIR_NONE:
-	default:
-#ifdef	SYM_OPT_HANDLE_DIR_UNKNOWN
-		cp->host_flags |= HF_DATA_IN;
-#endif
 		lastp = goalp = SCRIPTB_BA (np, no_data);
 		break;
+	case CAM_DIR_UNKNOWN:
+	default:
+		BUG();
 	}
 
 	/*
@@ -1229,14 +1200,6 @@
 	cp->phys.head.savep = cpu_to_scr(lastp);
 	cp->startp	    = cp->phys.head.savep;
 	cp->goalp	    = cpu_to_scr(goalp);
-
-#ifdef	SYM_OPT_HANDLE_DIR_UNKNOWN
-	/*
-	 *  If direction is unknown, start at data_io.
-	 */
-	if (dir == CAM_DIR_UNKNOWN)
-		cp->phys.head.savep = cpu_to_scr(SCRIPTB_BA (np, data_io));
-#endif
 }
 
 /*

Re: [PATCH, RFC] sym2: remove unkown data direction handling

[Matthew Wilcox]

On Tue, Nov 02, 2004 at 12:18:35PM +0100, Christoph Hellwig wrote:
> since 2.3 the LLDD gets the data direction passed down, so we don't
> need to kludge around an unknown data direction anymore.  I've added
> a BUG when we get an unkown data direction neverless, and it seems to
> survive so far under low load.

I thought we could get an unknown data direction from certain ioctls?

-- 
"Next the statesmen will invent cheap lies, putting the blame upon 
the nation that is attacked, and every man will be glad of those
conscience-soothing falsities, and will diligently study them, and refuse
to examine any refutations of them; and thus he will by and by convince 
himself that the war is just, and will thank God for the better sleep 
he enjoys after this process of grotesque self-deception." -- Mark Twain

Re: [PATCH, RFC] sym2: remove unkown data direction handling

[Christoph Hellwig]

On Tue, Nov 02, 2004 at 05:06:49PM +0000, Matthew Wilcox wrote:
> On Tue, Nov 02, 2004 at 12:18:35PM +0100, Christoph Hellwig wrote:
> > since 2.3 the LLDD gets the data direction passed down, so we don't
> > need to kludge around an unknown data direction anymore.  I've added
> > a BUG when we get an unkown data direction neverless, and it seems to
> > survive so far under low load.
> 
> I thought we could get an unknown data direction from certain ioctls?

Not anymore.  We could get the wrong direction from some older ioctls,
when not used as document but not an unkown one.

RE: [PATCH, RFC] sym2: remove unkown data direction handling

[Tony Battersby]

> > I thought we could get an unknown data direction from certain
ioctls?
>
> Not anymore.  We could get the wrong direction from some older ioctls,
> when not used as document but not an unkown one.

Isn't it still possible for a userspace program to specify
SG_DXFER_UNKNOWN when sending a command via /dev/sg* (not that it's a
good idea, but...)

http://gear.torque.net/sg/p/sg_v3_ho.html#AEN166

If you want to BUG() on an unknown data direction, then sg should return
an error to userspace when it sees SG_DXFER_UNKNOWN to avoid the BUG().

Anthony J. Battersby
Cybernetics