diff mbox

[4/4] sd: Optionally attach to ZBC devices

Message ID 1406645117-53088-5-git-send-email-hare@suse.de
State Not Applicable
Delegated to: David Miller
Headers show

Commit Message

Hannes Reinecke July 29, 2014, 2:45 p.m. UTC 
ZBC drives are close to disk devices, so sd.c is well
suited as a testbed for ZBC devices.
This patch introduces a module option 'attach_zbc' to
sd which will make the sd driver accept ZBC
devices as normal disk drives.

Signed-off-by: Hannes Reinecke <hare@suse.de>
---
 drivers/scsi/sd.c | 25 +++++++++++++++++++------
 1 file changed, 19 insertions(+), 6 deletions(-)

Comments

Christoph Hellwig July 29, 2014, 5:14 p.m. UTC | #1 
On Tue, Jul 29, 2014 at 04:45:17PM +0200, Hannes Reinecke wrote:
> ZBC drives are close to disk devices, so sd.c is well
> suited as a testbed for ZBC devices.
> This patch introduces a module option 'attach_zbc' to
> sd which will make the sd driver accept ZBC
> devices as normal disk drives.
> 
> Signed-off-by: Hannes Reinecke <hare@suse.de>

Looks reasonable to me.

I'd also really like a sysfs file that tells us if we're dealing
with a host aware device, as those report as TYPE_SBC. 

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Hannes Reinecke July 30, 2014, 6:41 a.m. UTC | #2 
On 07/29/2014 07:14 PM, Christoph Hellwig wrote:
> On Tue, Jul 29, 2014 at 04:45:17PM +0200, Hannes Reinecke wrote:
>> ZBC drives are close to disk devices, so sd.c is well
>> suited as a testbed for ZBC devices.
>> This patch introduces a module option 'attach_zbc' to
>> sd which will make the sd driver accept ZBC
>> devices as normal disk drives.
>>
>> Signed-off-by: Hannes Reinecke <hare@suse.de>
>
> Looks reasonable to me.
>
> I'd also really like a sysfs file that tells us if we're dealing
> with a host aware device, as those report as TYPE_SBC.
>
Yes, eventually. But can't we defer that to a next patchset?
I'd really like to have this one in, as it makes dealing with ZAC 
devices _so much_ easier ...

Cheers,

Hannes
Christoph Hellwig July 30, 2014, 11:39 a.m. UTC | #3 
On Wed, Jul 30, 2014 at 08:41:55AM +0200, Hannes Reinecke wrote:
> Yes, eventually. But can't we defer that to a next patchset?
> I'd really like to have this one in, as it makes dealing with ZAC devices
> _so much_ easier ...

I'm happy to put the sd patch in if I can get another review for it.

But even if you want me to carry the libata bits I will need a clear
ACK from Tejun.  And I really think it would belong into the libata
tree.

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diff mbox

Patch

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 377a520..f957a85 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -91,6 +91,13 @@  MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK15_MAJOR);
 MODULE_ALIAS_SCSI_DEVICE(TYPE_DISK);
 MODULE_ALIAS_SCSI_DEVICE(TYPE_MOD);
 MODULE_ALIAS_SCSI_DEVICE(TYPE_RBC);
+MODULE_ALIAS_SCSI_DEVICE(TYPE_ZBC);
+
+static bool sd_attach_zbc;
+
+module_param_named(attach_zbc, sd_attach_zbc, bool, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(attach_zbc,
+		  "Attach to ZBC devices (default=0)");
 
 #if !defined(CONFIG_DEBUG_BLOCK_EXT_DEVT)
 #define SD_MINORS	16
@@ -161,7 +168,7 @@  cache_type_store(struct device *dev, struct device_attribute *attr,
 	static const char temp[] = "temporary ";
 	int len;
 
-	if (sdp->type != TYPE_DISK)
+	if (sdp->type != TYPE_DISK && sdp->type != TYPE_ZBC)
 		/* no cache control on RBC devices; theoretically they
 		 * can do it, but there's probably so many exceptions
 		 * it's not worth the risk */
@@ -259,7 +266,7 @@  allow_restart_store(struct device *dev, struct device_attribute *attr,
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 
-	if (sdp->type != TYPE_DISK)
+	if (sdp->type != TYPE_DISK && sdp->type != TYPE_ZBC)
 		return -EINVAL;
 
 	sdp->allow_restart = simple_strtoul(buf, NULL, 10);
@@ -389,7 +396,7 @@  provisioning_mode_store(struct device *dev, struct device_attribute *attr,
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 
-	if (sdp->type != TYPE_DISK)
+	if (sdp->type != TYPE_DISK && sdp->type != TYPE_ZBC)
 		return -EINVAL;
 
 	if (!strncmp(buf, lbp_mode[SD_LBP_UNMAP], 20))
@@ -456,7 +463,7 @@  max_write_same_blocks_store(struct device *dev, struct device_attribute *attr,
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 
-	if (sdp->type != TYPE_DISK)
+	if (sdp->type != TYPE_DISK && sdp->type != TYPE_ZBC)
 		return -EINVAL;
 
 	err = kstrtoul(buf, 10, &max);
@@ -2537,7 +2544,7 @@  static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
 	struct scsi_mode_data data;
 	struct scsi_sense_hdr sshdr;
 
-	if (sdp->type != TYPE_DISK)
+	if (sdp->type != TYPE_DISK && sdp->type != TYPE_ZBC)
 		return;
 
 	if (sdkp->protection_type == 0)
@@ -2957,7 +2964,13 @@  static int sd_probe(struct device *dev)
 	int error;
 
 	error = -ENODEV;
-	if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC)
+	if (sdp->type != TYPE_DISK &&
+	    sdp->type != TYPE_MOD &&
+	    sdp->type != TYPE_RBC &&
+	    sdp->type != TYPE_ZBC)
+		goto out;
+
+	if (sdp->type == TYPE_ZBC && !sd_attach_zbc)
 		goto out;
 
 	SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp,