[PATCH] path_id: add handle_scsi_sas

[PATCH] path_id: add handle_scsi_sas

[harald]

From: Harald Hoyer <harald@redhat.com>

based on code by Jim Garlick.
---
 extras/path_id/path_id.c |   64 +++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 63 insertions(+), 1 deletions(-)

diff --git a/extras/path_id/path_id.c b/extras/path_id/path_id.c
index dcee378..8dbdd30 100644
--- a/extras/path_id/path_id.c
+++ b/extras/path_id/path_id.c
@@ -121,7 +121,69 @@ out:
 
 static struct udev_device *handle_scsi_sas(struct udev_device *parent, char **path)
 {
-	return NULL;
+	struct udev *udev  = udev_device_get_udev(parent);
+	struct udev_device *end_dev;
+	struct udev_device *sasdev;
+	struct udev_device *phydev;
+	struct udev_device *parent_dev;
+	struct udev_device *child_dev;
+	char syspath[UTIL_PATH_SIZE], *base;
+	char phy_path[UTIL_PATH_SIZE];
+	const char *end_name, *name, *enc, *bay;
+	const char *port_path;
+	int scsi_host;
+	int num_phys = 8;
+	int i;
+
+	parent_dev = parent;
+	while (1) {
+		child_dev = parent_dev;
+		parent_dev = udev_device_get_parent(child_dev);
+		if (parent_dev = NULL)
+			return NULL;
+		name = udev_device_get_sysname(parent_dev);
+		if (strstr(name, "end_device-")) {
+			end_dev = parent_dev;
+			end_name = name;
+		} else if (sscanf(name, "host%d", &scsi_host)) {
+			port_path = udev_device_get_syspath(child_dev);
+			break;
+		}
+	}
+
+	base = strdup(udev_device_get_syspath(end_dev));
+	if (!base)
+		return NULL;
+	snprintf(syspath, sizeof(syspath), "%s/sas_device/%s", base, end_name);
+	free(base);
+
+	for (i = 0 ; i < num_phys ; i++) {
+		snprintf(phy_path, sizeof(phy_path), "%s/phy-%d:%d",
+				port_path, scsi_host, i);
+		if (phydev = udev_device_new_from_syspath(udev, phy_path)) {
+			udev_device_unref(phydev);
+			break;
+		}
+	}
+	if (i = num_phys)
+		return NULL;
+
+	sasdev = udev_device_new_from_syspath(udev, syspath);
+	if (sasdev = NULL) {
+		fprintf(stderr, "unable to access '%s'\n", syspath);
+		return NULL;
+	}
+	enc = udev_device_get_sysattr_value(sasdev, "enclosure_identifier");
+	bay = udev_device_get_sysattr_value(sasdev, "bay_identifier");
+	if (bay = NULL) {
+		parent = NULL;
+		goto out;
+	}
+
+	path_prepend(path, "sas-%s-%s-%s", strrchr(phy_path, '/') + 1, enc : "unknown", bay);
+out:
+	udev_device_unref(sasdev);
+	return parent;
 }
 
 static struct udev_device *handle_scsi_iscsi(struct udev_device *parent, char **path)
-- 
1.7.0.1

[PATCH] path_id: add handle_scsi_sas

[harald]

From: Harald Hoyer <harald@redhat.com>

based on code by Jim Garlick.
---
 extras/path_id/path_id.c |   64 +++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 63 insertions(+), 1 deletions(-)

diff --git a/extras/path_id/path_id.c b/extras/path_id/path_id.c
index dcee378..c3d241b 100644
--- a/extras/path_id/path_id.c
+++ b/extras/path_id/path_id.c
@@ -121,7 +121,69 @@ out:
 
 static struct udev_device *handle_scsi_sas(struct udev_device *parent, char **path)
 {
-	return NULL;
+	struct udev *udev  = udev_device_get_udev(parent);
+	struct udev_device *end_dev;
+	struct udev_device *sasdev;
+	struct udev_device *phydev;
+	struct udev_device *parent_dev;
+	struct udev_device *child_dev;
+	char syspath[UTIL_PATH_SIZE], *base;
+	char phy_path[UTIL_PATH_SIZE];
+	const char *end_name, *name, *enc, *bay;
+	const char *port_path;
+	int scsi_host;
+	int num_phys = 8;
+	int i;
+
+	parent_dev = parent;
+	while (1) {
+		child_dev = parent_dev;
+		parent_dev = udev_device_get_parent(child_dev);
+		if (parent_dev = NULL)
+			return NULL;
+		name = udev_device_get_sysname(parent_dev);
+		if (strstr(name, "end_device-")) {
+			end_dev = parent_dev;
+			end_name = name;
+		} else if (sscanf(name, "host%d", &scsi_host)) {
+			port_path = udev_device_get_syspath(child_dev);
+			break;
+		}
+	}
+
+	base = strdup(udev_device_get_syspath(end_dev));
+	if (!base)
+		return NULL;
+	snprintf(syspath, sizeof(syspath), "%s/sas_device/%s", base, end_name);
+	free(base);
+
+	for (i = 0 ; i < num_phys ; i++) {
+		snprintf(phy_path, sizeof(phy_path), "%s/phy-%d:%d",
+				port_path, scsi_host, i);
+		if (phydev = udev_device_new_from_syspath(udev, phy_path)) {
+			udev_device_unref(phydev);
+			break;
+		}
+	}
+	if (i = num_phys)
+		return NULL;
+
+	sasdev = udev_device_new_from_syspath(udev, syspath);
+	if (sasdev = NULL) {
+		fprintf(stderr, "unable to access '%s'\n", syspath);
+		return NULL;
+	}
+	enc = udev_device_get_sysattr_value(sasdev, "enclosure_identifier");
+	bay = udev_device_get_sysattr_value(sasdev, "bay_identifier");
+	if (bay = NULL) {
+		parent = NULL;
+		goto out;
+	}
+
+	path_prepend(path, "sas-%s-%s-%s", strrchr(phy_path, '/') + 1, enc ? enc : "unknown", bay);
+out:
+	udev_device_unref(sasdev);
+	return parent;
 }
 
 static struct udev_device *handle_scsi_iscsi(struct udev_device *parent, char **path)
-- 
1.7.0.1

Re: [PATCH] path_id: add handle_scsi_sas

[Harald Hoyer]

On 06/25/2010 02:28 PM, harald@redhat.com wrote:
> +	path_prepend(path, "sas-%s-%s-%s", strrchr(phy_path, '/') + 1, enc : "unknown", bay);

copy & paste error here... revised patch follows

Re: [PATCH] path_id: add handle_scsi_sas

[Hannes Reinecke]

harald@redhat.com wrote:
> From: Harald Hoyer <harald@redhat.com>
> 
> based on code by Jim Garlick.
> ---
>  extras/path_id/path_id.c |   64 +++++++++++++++++++++++++++++++++++++++++++++-
>  1 files changed, 63 insertions(+), 1 deletions(-)
> 
> diff --git a/extras/path_id/path_id.c b/extras/path_id/path_id.c
> index dcee378..c3d241b 100644
> --- a/extras/path_id/path_id.c
> +++ b/extras/path_id/path_id.c
> @@ -121,7 +121,69 @@ out:
>  
>  static struct udev_device *handle_scsi_sas(struct udev_device *parent, char **path)
>  {
> -	return NULL;
> +	struct udev *udev  = udev_device_get_udev(parent);
> +	struct udev_device *end_dev;
> +	struct udev_device *sasdev;
> +	struct udev_device *phydev;
> +	struct udev_device *parent_dev;
> +	struct udev_device *child_dev;
> +	char syspath[UTIL_PATH_SIZE], *base;
> +	char phy_path[UTIL_PATH_SIZE];
> +	const char *end_name, *name, *enc, *bay;
> +	const char *port_path;
> +	int scsi_host;
> +	int num_phys = 8;
> +	int i;
> +
> +	parent_dev = parent;
> +	while (1) {
> +		child_dev = parent_dev;
> +		parent_dev = udev_device_get_parent(child_dev);
> +		if (parent_dev = NULL)
> +			return NULL;
> +		name = udev_device_get_sysname(parent_dev);
> +		if (strstr(name, "end_device-")) {
> +			end_dev = parent_dev;
> +			end_name = name;
> +		} else if (sscanf(name, "host%d", &scsi_host)) {
> +			port_path = udev_device_get_syspath(child_dev);
> +			break;
> +		}
> +	}
> +
This is wrong. The whole idea of path_id is that the path traversal is done
in one common loop, from which there are callouts to the individual device
handlers.

So we should be having one sas_end_device_handler and one sas_host handler.

I'll see to come up with an updated version.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		      zSeries & Storage
hare@suse.de			      +49 911 74053 688
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: Markus Rex, HRB 16746 (AG Nürnberg)

Re: [PATCH] path_id: add handle_scsi_sas

[Kay Sievers]

On Wed, Jul 7, 2010 at 12:20, Hannes Reinecke <hare@suse.de> wrote:
> This is wrong. The whole idea of path_id is that the path traversal is done
> in one common loop, from which there are callouts to the individual device
> handlers.

If you get a working update, please also remove the "unknown" stuff
from the returned string.

We must not return anything we are not entirely sure about, and the
strings must never change when something becomes "known" in the future
with some kernel/driver/sysfs update or anything similar.

In all such cases we better return nothing, than some random stuff we
can not keep reasonable stable.

Thanks,
Kay