[SCSI] iscsi: bidi support at the generic libiscsi level

- prepare the additional bidi_read rlength header. - access the right scsi_in() and/or scsi_out() side of things. also for resid. - Handle BIDI underflow overflow from target Signed-off-by: Boaz Harrosh <bharrosh@panasas.com> Reviewed-by: Pete Wyckoff <pw@osc.edu> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] iscsi: bidi support at the generic libiscsi level
- prepare the additional bidi_read rlength header. - access the right scsi_in() and/or scsi_out() side of things. also for resid. - Handle BIDI underflow overflow from target Signed-off-by: Boaz Harrosh <bharrosh@panasas.com> Reviewed-by: Pete Wyckoff <pw@osc.edu> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Boaz Harrosh · James Bottomley
1 parent 38d1c069db
Showing 1 changed file with 70 additions and 15 deletions Side-by-side Diff
drivers/scsi/libiscsi.c
@@ -176,6 +176,31 @@
 	return 0;
 }
  
+static int iscsi_prep_bidi_ahs(struct iscsi_cmd_task *ctask)
+{
+	struct scsi_cmnd *sc = ctask->sc;
+	struct iscsi_rlength_ahdr *rlen_ahdr;
+	int rc;
+
+	rlen_ahdr = iscsi_next_hdr(ctask);
+	rc = iscsi_add_hdr(ctask, sizeof(*rlen_ahdr));
+	if (rc)
+		return rc;
+
+	rlen_ahdr->ahslength =
+		cpu_to_be16(sizeof(rlen_ahdr->read_length) +
+						  sizeof(rlen_ahdr->reserved));
+	rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
+	rlen_ahdr->reserved = 0;
+	rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
+
+	debug_scsi("bidi-in rlen_ahdr->read_length(%d) "
+		   "rlen_ahdr->ahslength(%d)\n",
+		   be32_to_cpu(rlen_ahdr->read_length),
+		   be16_to_cpu(rlen_ahdr->ahslength));
+	return 0;
+}
+
 /**
  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
  * @ctask: iscsi cmd task
@@ -200,7 +225,6 @@
 	hdr->flags = ISCSI_ATTR_SIMPLE;
 	int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
 	hdr->itt = build_itt(ctask->itt, session->age);
-	hdr->data_length = cpu_to_be32(scsi_bufflen(sc));
 	hdr->cmdsn = cpu_to_be32(session->cmdsn);
 	session->cmdsn++;
 	hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
  
@@ -216,7 +240,15 @@
 	memcpy(hdr->cdb, sc->cmnd, cmd_len);
  
 	ctask->imm_count = 0;
+	if (scsi_bidi_cmnd(sc)) {
+		hdr->flags |= ISCSI_FLAG_CMD_READ;
+		rc = iscsi_prep_bidi_ahs(ctask);
+		if (rc)
+			return rc;
+	}
 	if (sc->sc_data_direction == DMA_TO_DEVICE) {
+		unsigned out_len = scsi_out(sc)->length;
+		hdr->data_length = cpu_to_be32(out_len);
 		hdr->flags |= ISCSI_FLAG_CMD_WRITE;
 		/*
 		 * Write counters:
  
  
@@ -237,19 +269,19 @@
 		ctask->unsol_datasn = 0;
  
 		if (session->imm_data_en) {
-			if (scsi_bufflen(sc) >= session->first_burst)
+			if (out_len >= session->first_burst)
 				ctask->imm_count = min(session->first_burst,
 							conn->max_xmit_dlength);
 			else
-				ctask->imm_count = min(scsi_bufflen(sc),
+				ctask->imm_count = min(out_len,
 							conn->max_xmit_dlength);
 			hton24(hdr->dlength, ctask->imm_count);
 		} else
 			zero_data(hdr->dlength);
  
 		if (!session->initial_r2t_en) {
-			ctask->unsol_count = min((session->first_burst),
-				(scsi_bufflen(sc))) - ctask->imm_count;
+			ctask->unsol_count = min(session->first_burst, out_len)
+							     - ctask->imm_count;
 			ctask->unsol_offset = ctask->imm_count;
 		}
  
@@ -259,6 +291,7 @@
 	} else {
 		hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 		zero_data(hdr->dlength);
+		hdr->data_length = cpu_to_be32(scsi_in(sc)->length);
  
 		if (sc->sc_data_direction == DMA_FROM_DEVICE)
 			hdr->flags |= ISCSI_FLAG_CMD_READ;
@@ -277,10 +310,12 @@
 		return EIO;
  
 	conn->scsicmd_pdus_cnt++;
-	debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x len %d "
-		"cmdsn %d win %d]\n",
-		sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
-		conn->id, sc, sc->cmnd[0], ctask->itt, scsi_bufflen(sc),
+	debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x "
+		"len %d bidi_len %d cmdsn %d win %d]\n",
+		scsi_bidi_cmnd(sc) ? "bidirectional" :
+		     sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
+		conn->id, sc, sc->cmnd[0], ctask->itt,
+		scsi_bufflen(sc), scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
 		session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
 	return 0;
 }
@@ -343,7 +378,12 @@
 		conn->session->tt->cleanup_cmd_task(conn, ctask);
  
 	sc->result = err;
-	scsi_set_resid(sc, scsi_bufflen(sc));
+	if (!scsi_bidi_cmnd(sc))
+		scsi_set_resid(sc, scsi_bufflen(sc));
+	else {
+		scsi_out(sc)->resid = scsi_out(sc)->length;
+		scsi_in(sc)->resid = scsi_in(sc)->length;
+	}
 	if (conn->ctask == ctask)
 		conn->ctask = NULL;
 	/* release ref from queuecommand */
@@ -478,6 +518,18 @@
 			   min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 	}
  
+	if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
+			   ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
+		int res_count = be32_to_cpu(rhdr->bi_residual_count);
+
+		if (scsi_bidi_cmnd(sc) && res_count > 0 &&
+				(rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW ||
+				 res_count <= scsi_in(sc)->length))
+			scsi_in(sc)->resid = res_count;
+		else
+			sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
+	}
+
 	if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
 	                   ISCSI_FLAG_CMD_OVERFLOW)) {
 		int res_count = be32_to_cpu(rhdr->residual_count);
  
@@ -485,13 +537,11 @@
 		if (res_count > 0 &&
 		    (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 		     res_count <= scsi_bufflen(sc)))
+			/* write side for bidi or uni-io set_resid */
 			scsi_set_resid(sc, res_count);
 		else
 			sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
-	} else if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
-	                          ISCSI_FLAG_CMD_BIDI_OVERFLOW))
-		sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
-
+	}
 out:
 	debug_scsi("done [sc %lx res %d itt 0x%x]\n",
 		   (long)sc, sc->result, ctask->itt);
@@ -1147,7 +1197,12 @@
 fault:
 	spin_unlock(&session->lock);
 	debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
-	scsi_set_resid(sc, scsi_bufflen(sc));
+	if (!scsi_bidi_cmnd(sc))
+		scsi_set_resid(sc, scsi_bufflen(sc));
+	else {
+		scsi_out(sc)->resid = scsi_out(sc)->length;
+		scsi_in(sc)->resid = scsi_in(sc)->length;
+	}
 	sc->scsi_done(sc);
 	spin_lock(host->host_lock);
 	return 0;
...	...	@@ -176,6 +176,31 @@
176	176	return 0;
177	177	}
178	178
	179	+static int iscsi_prep_bidi_ahs(struct iscsi_cmd_task *ctask)
	180	+{
	181	+ struct scsi_cmnd *sc = ctask->sc;
	182	+ struct iscsi_rlength_ahdr *rlen_ahdr;
	183	+ int rc;
	184	+
	185	+ rlen_ahdr = iscsi_next_hdr(ctask);
	186	+ rc = iscsi_add_hdr(ctask, sizeof(*rlen_ahdr));
	187	+ if (rc)
	188	+ return rc;
	189	+
	190	+ rlen_ahdr->ahslength =
	191	+ cpu_to_be16(sizeof(rlen_ahdr->read_length) +
	192	+ sizeof(rlen_ahdr->reserved));
	193	+ rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
	194	+ rlen_ahdr->reserved = 0;
	195	+ rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
	196	+
	197	+ debug_scsi("bidi-in rlen_ahdr->read_length(%d) "
	198	+ "rlen_ahdr->ahslength(%d)\n",
	199	+ be32_to_cpu(rlen_ahdr->read_length),
	200	+ be16_to_cpu(rlen_ahdr->ahslength));
	201	+ return 0;
	202	+}
	203	+
179	204	/**
180	205	* iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
181	206	* @ctask: iscsi cmd task
...	...	@@ -200,7 +225,6 @@
200	225	hdr->flags = ISCSI_ATTR_SIMPLE;
201	226	int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
202	227	hdr->itt = build_itt(ctask->itt, session->age);
203		- hdr->data_length = cpu_to_be32(scsi_bufflen(sc));
204	228	hdr->cmdsn = cpu_to_be32(session->cmdsn);
205	229	session->cmdsn++;
206	230	hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
207	231
...	...	@@ -216,7 +240,15 @@
216	240	memcpy(hdr->cdb, sc->cmnd, cmd_len);
217	241
218	242	ctask->imm_count = 0;
	243	+ if (scsi_bidi_cmnd(sc)) {
	244	+ hdr->flags \|= ISCSI_FLAG_CMD_READ;
	245	+ rc = iscsi_prep_bidi_ahs(ctask);
	246	+ if (rc)
	247	+ return rc;
	248	+ }
219	249	if (sc->sc_data_direction == DMA_TO_DEVICE) {
	250	+ unsigned out_len = scsi_out(sc)->length;
	251	+ hdr->data_length = cpu_to_be32(out_len);
220	252	hdr->flags \|= ISCSI_FLAG_CMD_WRITE;
221	253	/*
222	254	* Write counters:
223	255
224	256
...	...	@@ -237,19 +269,19 @@
237	269	ctask->unsol_datasn = 0;
238	270
239	271	if (session->imm_data_en) {
240		- if (scsi_bufflen(sc) >= session->first_burst)
	272	+ if (out_len >= session->first_burst)
241	273	ctask->imm_count = min(session->first_burst,
242	274	conn->max_xmit_dlength);
243	275	else
244		- ctask->imm_count = min(scsi_bufflen(sc),
	276	+ ctask->imm_count = min(out_len,
245	277	conn->max_xmit_dlength);
246	278	hton24(hdr->dlength, ctask->imm_count);
247	279	} else
248	280	zero_data(hdr->dlength);
249	281
250	282	if (!session->initial_r2t_en) {
251		- ctask->unsol_count = min((session->first_burst),
252		- (scsi_bufflen(sc))) - ctask->imm_count;
	283	+ ctask->unsol_count = min(session->first_burst, out_len)
	284	+ - ctask->imm_count;
253	285	ctask->unsol_offset = ctask->imm_count;
254	286	}
255	287
...	...	@@ -259,6 +291,7 @@
259	291	} else {
260	292	hdr->flags \|= ISCSI_FLAG_CMD_FINAL;
261	293	zero_data(hdr->dlength);
	294	+ hdr->data_length = cpu_to_be32(scsi_in(sc)->length);
262	295
263	296	if (sc->sc_data_direction == DMA_FROM_DEVICE)
264	297	hdr->flags \|= ISCSI_FLAG_CMD_READ;
...	...	@@ -277,10 +310,12 @@
277	310	return EIO;
278	311
279	312	conn->scsicmd_pdus_cnt++;
280		- debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x len %d "
281		- "cmdsn %d win %d]\n",
282		- sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
283		- conn->id, sc, sc->cmnd[0], ctask->itt, scsi_bufflen(sc),
	313	+ debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x "
	314	+ "len %d bidi_len %d cmdsn %d win %d]\n",
	315	+ scsi_bidi_cmnd(sc) ? "bidirectional" :
	316	+ sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
	317	+ conn->id, sc, sc->cmnd[0], ctask->itt,
	318	+ scsi_bufflen(sc), scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
284	319	session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
285	320	return 0;
286	321	}
...	...	@@ -343,7 +378,12 @@
343	378	conn->session->tt->cleanup_cmd_task(conn, ctask);
344	379
345	380	sc->result = err;
346		- scsi_set_resid(sc, scsi_bufflen(sc));
	381	+ if (!scsi_bidi_cmnd(sc))
	382	+ scsi_set_resid(sc, scsi_bufflen(sc));
	383	+ else {
	384	+ scsi_out(sc)->resid = scsi_out(sc)->length;
	385	+ scsi_in(sc)->resid = scsi_in(sc)->length;
	386	+ }
347	387	if (conn->ctask == ctask)
348	388	conn->ctask = NULL;
349	389	/* release ref from queuecommand */
...	...	@@ -478,6 +518,18 @@
478	518	min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
479	519	}
480	520
	521	+ if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW \|
	522	+ ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
	523	+ int res_count = be32_to_cpu(rhdr->bi_residual_count);
	524	+
	525	+ if (scsi_bidi_cmnd(sc) && res_count > 0 &&
	526	+ (rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW \|\|
	527	+ res_count <= scsi_in(sc)->length))
	528	+ scsi_in(sc)->resid = res_count;
	529	+ else
	530	+ sc->result = (DID_BAD_TARGET << 16) \| rhdr->cmd_status;
	531	+ }
	532	+
481	533	if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW \|
482	534	ISCSI_FLAG_CMD_OVERFLOW)) {
483	535	int res_count = be32_to_cpu(rhdr->residual_count);
484	536
...	...	@@ -485,13 +537,11 @@
485	537	if (res_count > 0 &&
486	538	(rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW \|\|
487	539	res_count <= scsi_bufflen(sc)))
	540	+ /* write side for bidi or uni-io set_resid */
488	541	scsi_set_resid(sc, res_count);
489	542	else
490	543	sc->result = (DID_BAD_TARGET << 16) \| rhdr->cmd_status;
491		- } else if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW \|
492		- ISCSI_FLAG_CMD_BIDI_OVERFLOW))
493		- sc->result = (DID_BAD_TARGET << 16) \| rhdr->cmd_status;
494		-
	544	+ }
495	545	out:
496	546	debug_scsi("done [sc %lx res %d itt 0x%x]\n",
497	547	(long)sc, sc->result, ctask->itt);
...	...	@@ -1147,7 +1197,12 @@
1147	1197	fault:
1148	1198	spin_unlock(&session->lock);
1149	1199	debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
1150		- scsi_set_resid(sc, scsi_bufflen(sc));
	1200	+ if (!scsi_bidi_cmnd(sc))
	1201	+ scsi_set_resid(sc, scsi_bufflen(sc));
	1202	+ else {
	1203	+ scsi_out(sc)->resid = scsi_out(sc)->length;
	1204	+ scsi_in(sc)->resid = scsi_in(sc)->length;
	1205	+ }
1151	1206	sc->scsi_done(sc);
1152	1207	spin_lock(host->host_lock);
1153	1208	return 0;