[SCSI] scsi_lib_dma: fix bug with dma maps on nested scsi objects

Some of our virtual SCSI hosts don't have a proper bus parent at the top, which can be a problem for doing DMA on them This patch makes the host device cache a pointer to the physical bus device and provides an extra API for setting it (the normal API picks it up from the parent). This patch also modifies the qla2xxx and lpfc vport logic to use the new DMA host setting API. Acked-By: James Smart <james.smart@emulex.com> Cc: Stable Tree <stable@kernel.org> Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] scsi_lib_dma: fix bug with dma maps on nested scsi objects
Some of our virtual SCSI hosts don't have a proper bus parent at the top, which can be a problem for doing DMA on them This patch makes the host device cache a pointer to the physical bus device and provides an extra API for setting it (the normal API picks it up from the parent). This patch also modifies the qla2xxx and lpfc vport logic to use the new DMA host setting API. Acked-By: James Smart <james.smart@emulex.com> Cc: Stable Tree <stable@kernel.org> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
James Bottomley · Eric Lee · Eric Lee · Eric Lee · Eric Lee · Eric Lee
1 parent 5917290ce9
Showing 5 changed files with 30 additions and 8 deletions Side-by-side Diff
drivers/scsi/hosts.c
drivers/scsi/lpfc/lpfc_init.c
drivers/scsi/qla2xxx/qla_attr.c
drivers/scsi/scsi_lib_dma.c
include/scsi/scsi_host.h
@@ -180,14 +180,20 @@
 EXPORT_SYMBOL(scsi_remove_host);
  
 /**
- * scsi_add_host - add a scsi host
+ * scsi_add_host_with_dma - add a scsi host with dma device
  * @shost:	scsi host pointer to add
  * @dev:	a struct device of type scsi class
+ * @dma_dev:	dma device for the host
  *
+ * Note: You rarely need to worry about this unless you're in a
+ * virtualised host environments, so use the simpler scsi_add_host()
+ * function instead.
+ *
  * Return value: 
  * 	0 on success / != 0 for error
  **/
-int scsi_add_host(struct Scsi_Host *shost, struct device *dev)
+int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
+			   struct device *dma_dev)
 {
 	struct scsi_host_template *sht = shost->hostt;
 	int error = -EINVAL;
@@ -207,6 +213,7 @@
  
 	if (!shost->shost_gendev.parent)
 		shost->shost_gendev.parent = dev ? dev : &platform_bus;
+	shost->dma_dev = dma_dev;
  
 	error = device_add(&shost->shost_gendev);
 	if (error)
@@ -262,7 +269,7 @@
  fail:
 	return error;
 }
-EXPORT_SYMBOL(scsi_add_host);
+EXPORT_SYMBOL(scsi_add_host_with_dma);
  
 static void scsi_host_dev_release(struct device *dev)
 {
@@ -2408,7 +2408,7 @@
 	vport->els_tmofunc.function = lpfc_els_timeout;
 	vport->els_tmofunc.data = (unsigned long)vport;
  
-	error = scsi_add_host(shost, dev);
+	error = scsi_add_host_with_dma(shost, dev, &phba->pcidev->dev);
 	if (error)
 		goto out_put_shost;
  
@@ -1654,7 +1654,8 @@
 			fc_vport_set_state(fc_vport, FC_VPORT_LINKDOWN);
 	}
  
-	if (scsi_add_host(vha->host, &fc_vport->dev)) {
+	if (scsi_add_host_with_dma(vha->host, &fc_vport->dev,
+				   &ha->pdev->dev)) {
 		DEBUG15(printk("scsi(%ld): scsi_add_host failure for VP[%d].\n",
 			vha->host_no, vha->vp_idx));
 		goto vport_create_failed_2;
@@ -23,7 +23,7 @@
 	int nseg = 0;
  
 	if (scsi_sg_count(cmd)) {
-		struct device *dev = cmd->device->host->shost_gendev.parent;
+		struct device *dev = cmd->device->host->dma_dev;
  
 		nseg = dma_map_sg(dev, scsi_sglist(cmd), scsi_sg_count(cmd),
 				  cmd->sc_data_direction);
@@ -41,7 +41,7 @@
 void scsi_dma_unmap(struct scsi_cmnd *cmd)
 {
 	if (scsi_sg_count(cmd)) {
-		struct device *dev = cmd->device->host->shost_gendev.parent;
+		struct device *dev = cmd->device->host->dma_dev;
  
 		dma_unmap_sg(dev, scsi_sglist(cmd), scsi_sg_count(cmd),
 			     cmd->sc_data_direction);
@@ -683,6 +683,12 @@
 	void *shost_data;
  
 	/*
+	 * Points to the physical bus device we'd use to do DMA
+	 * Needed just in case we have virtual hosts.
+	 */
+	struct device *dma_dev;
+
+	/*
 	 * We should ensure that this is aligned, both for better performance
 	 * and also because some compilers (m68k) don't automatically force
 	 * alignment to a long boundary.
@@ -726,7 +732,9 @@
 extern void scsi_flush_work(struct Scsi_Host *);
  
 extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int);
-extern int __must_check scsi_add_host(struct Scsi_Host *, struct device *);
+extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
+					       struct device *,
+					       struct device *);
 extern void scsi_scan_host(struct Scsi_Host *);
 extern void scsi_rescan_device(struct device *);
 extern void scsi_remove_host(struct Scsi_Host *);
@@ -736,6 +744,12 @@
 extern const char *scsi_host_state_name(enum scsi_host_state);
  
 extern u64 scsi_calculate_bounce_limit(struct Scsi_Host *);
+
+static inline int __must_check scsi_add_host(struct Scsi_Host *host,
+					     struct device *dev)
+{
+	return scsi_add_host_with_dma(host, dev, dev);
+}
  
 static inline struct device *scsi_get_device(struct Scsi_Host *shost)
 {
...	...	@@ -180,14 +180,20 @@
180	180	EXPORT_SYMBOL(scsi_remove_host);
181	181
182	182	/**
183		- * scsi_add_host - add a scsi host
	183	+ * scsi_add_host_with_dma - add a scsi host with dma device
184	184	* @shost: scsi host pointer to add
185	185	* @dev: a struct device of type scsi class
	186	+ * @dma_dev: dma device for the host
186	187	*
	188	+ * Note: You rarely need to worry about this unless you're in a
	189	+ * virtualised host environments, so use the simpler scsi_add_host()
	190	+ * function instead.
	191	+ *
187	192	* Return value:
188	193	* 0 on success / != 0 for error
189	194	**/
190		-int scsi_add_host(struct Scsi_Host shost, struct device dev)
	195	+int scsi_add_host_with_dma(struct Scsi_Host shost, struct device dev,
	196	+ struct device *dma_dev)
191	197	{
192	198	struct scsi_host_template *sht = shost->hostt;
193	199	int error = -EINVAL;
...	...	@@ -207,6 +213,7 @@
207	213
208	214	if (!shost->shost_gendev.parent)
209	215	shost->shost_gendev.parent = dev ? dev : &platform_bus;
	216	+ shost->dma_dev = dma_dev;
210	217
211	218	error = device_add(&shost->shost_gendev);
212	219	if (error)
...	...	@@ -262,7 +269,7 @@
262	269	fail:
263	270	return error;
264	271	}
265		-EXPORT_SYMBOL(scsi_add_host);
	272	+EXPORT_SYMBOL(scsi_add_host_with_dma);
266	273
267	274	static void scsi_host_dev_release(struct device *dev)
268	275	{
...	...	@@ -2408,7 +2408,7 @@
2408	2408	vport->els_tmofunc.function = lpfc_els_timeout;
2409	2409	vport->els_tmofunc.data = (unsigned long)vport;
2410	2410
2411		- error = scsi_add_host(shost, dev);
	2411	+ error = scsi_add_host_with_dma(shost, dev, &phba->pcidev->dev);
2412	2412	if (error)
2413	2413	goto out_put_shost;
2414	2414
...	...	@@ -1654,7 +1654,8 @@
1654	1654	fc_vport_set_state(fc_vport, FC_VPORT_LINKDOWN);
1655	1655	}
1656	1656
1657		- if (scsi_add_host(vha->host, &fc_vport->dev)) {
	1657	+ if (scsi_add_host_with_dma(vha->host, &fc_vport->dev,
	1658	+ &ha->pdev->dev)) {
1658	1659	DEBUG15(printk("scsi(%ld): scsi_add_host failure for VP[%d].\n",
1659	1660	vha->host_no, vha->vp_idx));
1660	1661	goto vport_create_failed_2;
...	...	@@ -23,7 +23,7 @@
23	23	int nseg = 0;
24	24
25	25	if (scsi_sg_count(cmd)) {
26		- struct device *dev = cmd->device->host->shost_gendev.parent;
	26	+ struct device *dev = cmd->device->host->dma_dev;
27	27
28	28	nseg = dma_map_sg(dev, scsi_sglist(cmd), scsi_sg_count(cmd),
29	29	cmd->sc_data_direction);
...	...	@@ -41,7 +41,7 @@
41	41	void scsi_dma_unmap(struct scsi_cmnd *cmd)
42	42	{
43	43	if (scsi_sg_count(cmd)) {
44		- struct device *dev = cmd->device->host->shost_gendev.parent;
	44	+ struct device *dev = cmd->device->host->dma_dev;
45	45
46	46	dma_unmap_sg(dev, scsi_sglist(cmd), scsi_sg_count(cmd),
47	47	cmd->sc_data_direction);
...	...	@@ -683,6 +683,12 @@
683	683	void *shost_data;
684	684
685	685	/*
	686	+ * Points to the physical bus device we'd use to do DMA
	687	+ * Needed just in case we have virtual hosts.
	688	+ */
	689	+ struct device *dma_dev;
	690	+
	691	+ /*
686	692	* We should ensure that this is aligned, both for better performance
687	693	* and also because some compilers (m68k) don't automatically force
688	694	* alignment to a long boundary.
...	...	@@ -726,7 +732,9 @@
726	732	extern void scsi_flush_work(struct Scsi_Host *);
727	733
728	734	extern struct Scsi_Host scsi_host_alloc(struct scsi_host_template , int);
729		-extern int __must_check scsi_add_host(struct Scsi_Host , struct device );
	735	+extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
	736	+ struct device *,
	737	+ struct device *);
730	738	extern void scsi_scan_host(struct Scsi_Host *);
731	739	extern void scsi_rescan_device(struct device *);
732	740	extern void scsi_remove_host(struct Scsi_Host *);
...	...	@@ -736,6 +744,12 @@
736	744	extern const char *scsi_host_state_name(enum scsi_host_state);
737	745
738	746	extern u64 scsi_calculate_bounce_limit(struct Scsi_Host *);
	747	+
	748	+static inline int __must_check scsi_add_host(struct Scsi_Host *host,
	749	+ struct device *dev)
	750	+{
	751	+ return scsi_add_host_with_dma(host, dev, dev);
	752	+}
739	753
740	754	static inline struct device scsi_get_device(struct Scsi_Host shost)
741	755	{