[PATCH] ibft: Expose iBFT acpi header via sysfs

David Bond
2016-03-24T01:49:43Z

Some ethernet adapter vendors are supplying products which support optional
(payed license) features. On some adapters this includes a hardware iscsi
initiator. The same adapters in a normal (no extra licenses) mode of
operation can be used as a software iscsi initiator. In addition, software
iscsi boot initiators are becoming a standard part of many vendors uefi
implementations. This is creating difficulties during early boot/install
determining the proper configuration method for these adapters when they
are used as a boot device.

The attached patch creates sysfs entries to expose information from the
acpi header of the ibft table. This information allows for a method to
easily determining if an ibft table was created by a ethernet card's
firmware or the system uefi/bios. In the case of a hardware initiator this
information in combination with the pci vendor and device id can be used
to ascertain any vendor specific behaviors that need to be accommodated.

Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: David Bond <dbond@suse.com>
---
Documentation/ABI/testing/sysfs-ibft | 10 ++++++
drivers/firmware/iscsi_ibft.c | 64 +++++++++++++++++++++++++++++++++++-
drivers/scsi/iscsi_boot_sysfs.c | 62 ++++++++++++++++++++++++++++++++++
include/linux/iscsi_boot_sysfs.h | 13 ++++++++
4 files changed, 148 insertions(+), 1 deletion(-)

diff --git a/Documentation/ABI/testing/sysfs-ibft b/Documentation/ABI/testing/sysfs-ibft
index cac3930..7d6725f 100644
--- a/Documentation/ABI/testing/sysfs-ibft
+++ b/Documentation/ABI/testing/sysfs-ibft
@@ -21,3 +21,13 @@ Contact: Konrad Rzeszutek <ketuzsezr@darnok.org>
Description: The /sys/firmware/ibft/ethernetX directory will contain
files that expose the iSCSI Boot Firmware Table NIC data.
Usually this contains the IP address, MAC, and gateway of the NIC.
+
+What: /sys/firmware/ibft/acpi_header
+Date: March 2016
+Contact: David Bond <dbond@suse.com>
+Description: The /sys/firmware/ibft/acpi_header directory will contain files
+ that expose the SIGNATURE, OEM_ID, and OEM_TABLE_ID fields of the
+ acpi table header of the iBFT structure. This will allow for
+ identification of the creator of the table which is useful in
+ determining quirks associated with some adapters when used in
+ hardware vs software iscsi initiator mode.
diff --git a/drivers/firmware/iscsi_ibft.c b/drivers/firmware/iscsi_ibft.c
index 81037e5..2b1900b 100644
--- a/drivers/firmware/iscsi_ibft.c
+++ b/drivers/firmware/iscsi_ibft.c
@@ -418,6 +418,31 @@ static ssize_t ibft_attr_show_target(void *data, int type, char *buf)
return str - buf;
}

+static ssize_t ibft_attr_show_acpitbl(void *data, int type, char *buf)
+{
+ struct ibft_kobject *entry = data;
+ char *str = buf;
+
+ switch (type) {
+ case ISCSI_BOOT_ACPITBL_SIGNATURE:
+ str += sprintf_string(str, ACPI_NAME_SIZE,
+ entry->header->header.signature);
+ break;
+ case ISCSI_BOOT_ACPITBL_OEM_ID:
+ str += sprintf_string(str, ACPI_OEM_ID_SIZE,
+ entry->header->header.oem_id);
+ break;
+ case ISCSI_BOOT_ACPITBL_OEM_TABLE_ID:
+ str += sprintf_string(str, ACPI_OEM_TABLE_ID_SIZE,
+ entry->header->header.oem_table_id);
+ break;
+ default:
+ break;
+ }
+
+ return str - buf;
+}
+
static int __init ibft_check_device(void)
{
int len;
@@ -576,6 +601,24 @@ static umode_t __init ibft_check_initiator_for(void *data, int type)
return rc;
}

+static umode_t __init ibft_check_acpitbl_for(void *data, int type)
+{
+
+ umode_t rc = 0;
+
+ switch (type) {
+ case ISCSI_BOOT_ACPITBL_SIGNATURE:
+ case ISCSI_BOOT_ACPITBL_OEM_ID:
+ case ISCSI_BOOT_ACPITBL_OEM_TABLE_ID:
+ rc = S_IRUGO;
+ break;
+ default:
+ break;
+ }
+
+ return rc;
+}
+
static void ibft_kobj_release(void *data)
{
kfree(data);
@@ -699,6 +742,8 @@ free_ibft_obj:
static int __init ibft_register_kobjects(struct acpi_table_ibft *header)
{
struct ibft_control *control = NULL;
+ struct iscsi_boot_kobj *boot_kobj;
+ struct ibft_kobject *ibft_kobj;
void *ptr, *end;
int rc = 0;
u16 offset;
@@ -727,6 +772,23 @@ static int __init ibft_register_kobjects(struct acpi_table_ibft *header)
}
}

+ ibft_kobj = kzalloc(sizeof(*ibft_kobj), GFP_KERNEL);
+ if (!ibft_kobj)
+ return -ENOMEM;
+
+ ibft_kobj->header = header;
+ ibft_kobj->hdr = NULL; /*for ibft_unregister*/
+
+ boot_kobj = iscsi_boot_create_acpitbl(boot_kset, 0,
+ ibft_kobj,
+ ibft_attr_show_acpitbl,
+ ibft_check_acpitbl_for,
+ ibft_kobj_release);
+ if (!boot_kobj) {
+ kfree(ibft_kobj);
+ rc = -ENOMEM;
+ }
+
return rc;
}

@@ -738,7 +800,7 @@ static void ibft_unregister(void)
list_for_each_entry_safe(boot_kobj, tmp_kobj,
&boot_kset->kobj_list, list) {
ibft_kobj = boot_kobj->data;
- if (ibft_kobj->hdr->id == id_nic)
+ if (ibft_kobj->hdr && ibft_kobj->hdr->id == id_nic)
sysfs_remove_link(&boot_kobj->kobj, "device");
};
}
diff --git a/drivers/scsi/iscsi_boot_sysfs.c b/drivers/scsi/iscsi_boot_sysfs.c
index 8f0ea97..b472f56 100644
--- a/drivers/scsi/iscsi_boot_sysfs.c
+++ b/drivers/scsi/iscsi_boot_sysfs.c
@@ -306,6 +306,42 @@ static struct attribute_group iscsi_boot_initiator_attr_group = {
.is_visible = iscsi_boot_ini_attr_is_visible,
};

+/* iBFT ACPI Table attributes */
+iscsi_boot_rd_attr(acpitbl_signature, signature, ISCSI_BOOT_ACPITBL_SIGNATURE);
+iscsi_boot_rd_attr(acpitbl_oem_id, oem_id, ISCSI_BOOT_ACPITBL_OEM_ID);
+iscsi_boot_rd_attr(acpitbl_oem_table_id, oem_table_id,
+ ISCSI_BOOT_ACPITBL_OEM_TABLE_ID);
+
+static struct attribute *acpitbl_attrs[] = {
+ &iscsi_boot_attr_acpitbl_signature.attr,
+ &iscsi_boot_attr_acpitbl_oem_id.attr,
+ &iscsi_boot_attr_acpitbl_oem_table_id.attr,
+ NULL
+};
+
+static umode_t iscsi_boot_acpitbl_attr_is_visible(struct kobject *kobj,
+ struct attribute *attr, int i)
+{
+ struct iscsi_boot_kobj *boot_kobj =
+ container_of(kobj, struct iscsi_boot_kobj, kobj);
+
+ if (attr == &iscsi_boot_attr_acpitbl_signature.attr)
+ return boot_kobj->is_visible(boot_kobj->data,
+ ISCSI_BOOT_ACPITBL_SIGNATURE);
+ if (attr == &iscsi_boot_attr_acpitbl_oem_id.attr)
+ return boot_kobj->is_visible(boot_kobj->data,
+ ISCSI_BOOT_ACPITBL_OEM_ID);
+ if (attr == &iscsi_boot_attr_acpitbl_oem_table_id.attr)
+ return boot_kobj->is_visible(boot_kobj->data,
+ ISCSI_BOOT_ACPITBL_OEM_TABLE_ID);
+ return 0;
+}
+
+static struct attribute_group iscsi_boot_acpitbl_attr_group = {
+ .attrs = acpitbl_attrs,
+ .is_visible = iscsi_boot_acpitbl_attr_is_visible,
+};
+
static struct iscsi_boot_kobj *
iscsi_boot_create_kobj(struct iscsi_boot_kset *boot_kset,
struct attribute_group *attr_group,
@@ -436,6 +472,32 @@ iscsi_boot_create_ethernet(struct iscsi_boot_kset *boot_kset, int index,
EXPORT_SYMBOL_GPL(iscsi_boot_create_ethernet);

/**
+ * iscsi_boot_create_acpitbl() - create boot acpi table sysfs dir
+ * @boot_kset: boot kset
+ * @index: not used
+ * @data: driver specific data
+ * @show: attr show function
+ * @is_visible: attr visibility function
+ * @release: release function
+ *
+ * Note: The boot sysfs lib will free the data passed in for the caller
+ * when all refs to the acpitbl kobject have been released.
+ */
+struct iscsi_boot_kobj *
+iscsi_boot_create_acpitbl(struct iscsi_boot_kset *boot_kset, int index,
+ void *data,
+ ssize_t (*show)(void *data, int type, char *buf),
+ umode_t (*is_visible)(void *data, int type),
+ void (*release)(void *data))
+{
+ return iscsi_boot_create_kobj(boot_kset,
+ &iscsi_boot_acpitbl_attr_group,
+ "acpi_header", index, data, show,
+ is_visible, release);
+}
+EXPORT_SYMBOL_GPL(iscsi_boot_create_acpitbl);
+
+/**
* iscsi_boot_create_kset() - creates root sysfs tree
* @set_name: name of root dir
*/
diff --git a/include/linux/iscsi_boot_sysfs.h b/include/linux/iscsi_boot_sysfs.h
index 548d553..10923d7 100644
--- a/include/linux/iscsi_boot_sysfs.h
+++ b/include/linux/iscsi_boot_sysfs.h
@@ -64,6 +64,12 @@ enum iscsi_boot_initiator_properties_enum {
ISCSI_BOOT_INI_END_MARKER,
};

+enum iscsi_boot_acpitbl_properties_enum {
+ ISCSI_BOOT_ACPITBL_SIGNATURE,
+ ISCSI_BOOT_ACPITBL_OEM_ID,
+ ISCSI_BOOT_ACPITBL_OEM_TABLE_ID,
+};
+
struct attribute_group;

struct iscsi_boot_kobj {
@@ -127,6 +133,13 @@ iscsi_boot_create_target(struct iscsi_boot_kset *boot_kset, int index,
umode_t (*is_visible) (void *data, int type),
void (*release) (void *data));

+struct iscsi_boot_kobj *
+iscsi_boot_create_acpitbl(struct iscsi_boot_kset *boot_kset, int index,
+ void *data,
+ ssize_t (*show)(void *data, int type, char *buf),
+ umode_t (*is_visible)(void *data, int type),
+ void (*release)(void *data));
+
struct iscsi_boot_kset *iscsi_boot_create_kset(const char *set_name);
struct iscsi_boot_kset *iscsi_boot_create_host_kset(unsigned int hostno);
void iscsi_boot_destroy_kset(struct iscsi_boot_kset *boot_kset);
--
2.6.2