diff mbox series

[RESEND,v2,01/11] scsi: scsi_debug: Don't hold driver host struct pointer in host->hostdata[]

Message ID 20230313093114.1498305-2-john.g.garry@oracle.com (mailing list archive)
State Accepted
Headers show
Series scsi_debug: Some minor improvements | expand

Commit Message

John Garry March 13, 2023, 9:31 a.m. UTC 
This driver stores just a pointer to the driver host structure in
host->hostdata[]. Most other drivers actually have the driver host
structure allocated in host->hostdata[], but this driver is different as
we allocate that memory separately before allocating the shost memory.

However there is no need to allocate this memory only in host->hostdata[]
when we can already look up the driver host structure from shost->dma_dev,
so add a macro for this - shost_to_sdebug_host(). Rename to_sdebug_host()
-> dev_to_sdebug_host() to avoid ambiguity.

Also remove a check for !sdbg_host in find_build_dev_info(), as this cannot
be true. Other similar checks will be later removed.

Signed-off-by: John Garry <john.g.garry@oracle.com>
---
 drivers/scsi/scsi_debug.c | 24 +++++++++++-------------
 1 file changed, 11 insertions(+), 13 deletions(-)

Comments

Douglas Gilbert March 14, 2023, 2:34 a.m. UTC | #1 
On 2023-03-13 05:31, John Garry wrote:
> This driver stores just a pointer to the driver host structure in
> host->hostdata[]. Most other drivers actually have the driver host
> structure allocated in host->hostdata[], but this driver is different as
> we allocate that memory separately before allocating the shost memory.
> 
> However there is no need to allocate this memory only in host->hostdata[]
> when we can already look up the driver host structure from shost->dma_dev,
> so add a macro for this - shost_to_sdebug_host(). Rename to_sdebug_host()
> -> dev_to_sdebug_host() to avoid ambiguity.
> 
> Also remove a check for !sdbg_host in find_build_dev_info(), as this cannot
> be true. Other similar checks will be later removed.
> 
> Signed-off-by: John Garry <john.g.garry@oracle.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>

Please apply my "ack" to the rest of this series (2 through 11).

Good the have other eyes looking at this driver and making
improvements.

Thanks
Doug Gilbert
John Garry March 16, 2023, 8:48 a.m. UTC | #2 
On 14/03/2023 02:34, Douglas Gilbert wrote:
> 2023-03-13 05:31, John Garry wrote:
>> This driver stores just a pointer to the driver host structure in
>> host->hostdata[]. Most other drivers actually have the driver host
>> structure allocated in host->hostdata[], but this driver is different as
>> we allocate that memory separately before allocating the shost memory.
>>
>> However there is no need to allocate this memory only in host->hostdata[]
>> when we can already look up the driver host structure from 
>> shost->dma_dev,
>> so add a macro for this - shost_to_sdebug_host(). Rename to_sdebug_host()
>> -> dev_to_sdebug_host() to avoid ambiguity.
>>
>> Also remove a check for !sdbg_host in find_build_dev_info(), as this 
>> cannot
>> be true. Other similar checks will be later removed.
>>
>> Signed-off-by: John Garry <john.g.garry@oracle.com>
> Acked-by: Douglas Gilbert <dgilbert@interlog.com>
> 
> Please apply my "ack" to the rest of this series (2 through 11).
> 

Thanks.

Hi Martin, Please let me know if you would like me to send the series 
again with Doug's tags appended.

> Good the have other eyes looking at this driver and making
> improvements.

No worries, Please check the other series which I sent when you can. I 
am not sure how to solve the issue related to the last patch there. 
Maybe a solution would be to just remove all the shosts and then re-add 
with updated can_queue.

John
diff mbox series

Patch

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 72149eeee6e6..554c03d7a648 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -324,9 +324,12 @@  struct sdeb_store_info {
 	void *map_storep;	/* provisioning map */
 };
 
-#define to_sdebug_host(d)	\
+#define dev_to_sdebug_host(d)	\
 	container_of(d, struct sdebug_host_info, dev)
 
+#define shost_to_sdebug_host(shost)	\
+	dev_to_sdebug_host(shost->dma_dev)
+
 enum sdeb_defer_type {SDEB_DEFER_NONE = 0, SDEB_DEFER_HRT = 1,
 		      SDEB_DEFER_WQ = 2, SDEB_DEFER_POLL = 3};
 
@@ -5166,11 +5169,7 @@  static struct sdebug_dev_info *find_build_dev_info(struct scsi_device *sdev)
 	struct sdebug_dev_info *open_devip = NULL;
 	struct sdebug_dev_info *devip;
 
-	sdbg_host = *(struct sdebug_host_info **)shost_priv(sdev->host);
-	if (!sdbg_host) {
-		pr_err("Host info NULL\n");
-		return NULL;
-	}
+	sdbg_host = shost_to_sdebug_host(sdev->host);
 
 	list_for_each_entry(devip, &sdbg_host->dev_info_list, dev_list) {
 		if ((devip->used) && (devip->channel == sdev->channel) &&
@@ -5407,7 +5406,7 @@  static int scsi_debug_target_reset(struct scsi_cmnd *SCpnt)
 	hp = sdp->host;
 	if (!hp)
 		goto lie;
-	sdbg_host = *(struct sdebug_host_info **)shost_priv(hp);
+	sdbg_host = shost_to_sdebug_host(hp);
 	if (sdbg_host) {
 		list_for_each_entry(devip,
 				    &sdbg_host->dev_info_list,
@@ -5440,7 +5439,7 @@  static int scsi_debug_bus_reset(struct scsi_cmnd *SCpnt)
 		sdev_printk(KERN_INFO, sdp, "%s\n", __func__);
 	hp = sdp->host;
 	if (hp) {
-		sdbg_host = *(struct sdebug_host_info **)shost_priv(hp);
+		sdbg_host = shost_to_sdebug_host(hp);
 		if (sdbg_host) {
 			list_for_each_entry(devip,
 					    &sdbg_host->dev_info_list,
@@ -7165,7 +7164,7 @@  static void sdebug_release_adapter(struct device *dev)
 {
 	struct sdebug_host_info *sdbg_host;
 
-	sdbg_host = to_sdebug_host(dev);
+	sdbg_host = dev_to_sdebug_host(dev);
 	kfree(sdbg_host);
 }
 
@@ -7812,14 +7811,14 @@  static int sdebug_driver_probe(struct device *dev)
 	struct Scsi_Host *hpnt;
 	int hprot;
 
-	sdbg_host = to_sdebug_host(dev);
+	sdbg_host = dev_to_sdebug_host(dev);
 
 	sdebug_driver_template.can_queue = sdebug_max_queue;
 	sdebug_driver_template.cmd_per_lun = sdebug_max_queue;
 	if (!sdebug_clustering)
 		sdebug_driver_template.dma_boundary = PAGE_SIZE - 1;
 
-	hpnt = scsi_host_alloc(&sdebug_driver_template, sizeof(sdbg_host));
+	hpnt = scsi_host_alloc(&sdebug_driver_template, 0);
 	if (NULL == hpnt) {
 		pr_err("scsi_host_alloc failed\n");
 		error = -ENODEV;
@@ -7862,7 +7861,6 @@  static int sdebug_driver_probe(struct device *dev)
 		hpnt->nr_maps = 3;
 
 	sdbg_host->shost = hpnt;
-	*((struct sdebug_host_info **)hpnt->hostdata) = sdbg_host;
 	if ((hpnt->this_id >= 0) && (sdebug_num_tgts > hpnt->this_id))
 		hpnt->max_id = sdebug_num_tgts + 1;
 	else
@@ -7936,7 +7934,7 @@  static void sdebug_driver_remove(struct device *dev)
 	struct sdebug_host_info *sdbg_host;
 	struct sdebug_dev_info *sdbg_devinfo, *tmp;
 
-	sdbg_host = to_sdebug_host(dev);
+	sdbg_host = dev_to_sdebug_host(dev);
 
 	scsi_remove_host(sdbg_host->shost);