[PATCH 1/2] target/configfs: Kill se_device->dev_link_magic

Nicholas A. Bellinger
2017-06-01T10:38:00Z

From: Nicholas Bellinger <nab@linux-iscsi.org>

Instead of using a hardcoded magic value in se_device when verifying
a target config_item symlink source during target_fabric_port_link(),
go ahead and use target_core_dev_item_ops directly instead.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
---
drivers/target/target_core_configfs.c | 6 +++++-
drivers/target/target_core_device.c | 1 -
drivers/target/target_core_fabric_configfs.c | 12 +++++++-----
include/target/target_core_base.h | 2 --
4 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c
index 0326607..9b8abd5 100644
--- a/drivers/target/target_core_configfs.c
+++ b/drivers/target/target_core_configfs.c
@@ -2236,7 +2236,11 @@ static void target_core_dev_release(struct config_item *item)
target_free_device(dev);
}

-static struct configfs_item_operations target_core_dev_item_ops = {
+/*
+ * Used in target_core_fabric_configfs.c to verify valid se_device symlink
+ * within target_fabric_port_link()
+ */
+struct configfs_item_operations target_core_dev_item_ops = {
.release = target_core_dev_release,
};

diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index a5762e6..e4771ce 100644
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -756,7 +756,6 @@ struct se_device *target_alloc_device(struct se_hba *hba, const char *name)
if (!dev)
return NULL;

- dev->dev_link_magic = SE_DEV_LINK_MAGIC;
dev->se_hba = hba;
dev->transport = hba->backend->ops;
dev->prot_length = sizeof(struct t10_pi_tuple);
diff --git a/drivers/target/target_core_fabric_configfs.c b/drivers/target/target_core_fabric_configfs.c
index d1e6cab..2cbaecd 100644
--- a/drivers/target/target_core_fabric_configfs.c
+++ b/drivers/target/target_core_fabric_configfs.c
@@ -620,6 +620,8 @@ static ssize_t target_fabric_port_alua_tg_pt_write_md_store(
NULL,
};

+extern struct configfs_item_operations target_core_dev_item_ops;
+
static int target_fabric_port_link(
struct config_item *lun_ci,
struct config_item *se_dev_ci)
@@ -628,16 +630,16 @@ static int target_fabric_port_link(
struct se_lun *lun = container_of(to_config_group(lun_ci),
struct se_lun, lun_group);
struct se_portal_group *se_tpg;
- struct se_device *dev =
- container_of(to_config_group(se_dev_ci), struct se_device, dev_group);
+ struct se_device *dev;
struct target_fabric_configfs *tf;
int ret;

- if (dev->dev_link_magic != SE_DEV_LINK_MAGIC) {
- pr_err("Bad dev->dev_link_magic, not a valid se_dev_ci pointer:"
- " %p to struct se_device: %p\n", se_dev_ci, dev);
+ if (!se_dev_ci->ci_type ||
+ se_dev_ci->ci_type->ct_item_ops != &target_core_dev_item_ops) {
+ pr_err("Bad se_dev_ci, not a valid se_dev_ci pointer: %p\n", se_dev_ci);
return -EFAULT;
}
+ dev = container_of(to_config_group(se_dev_ci), struct se_device, dev_group);

if (!(dev->dev_flags & DF_CONFIGURED)) {
pr_err("se_device not configured yet, cannot port link\n");
diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h
index 0c1dce2..c3c14d0 100644
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -746,8 +746,6 @@ struct se_dev_stat_grps {
};

struct se_device {
-#define SE_DEV_LINK_MAGIC 0xfeeddeef
- u32 dev_link_magic;
/* RELATIVE TARGET PORT IDENTIFER Counter */
u16 dev_rpti_counter;
/* Used for SAM Task Attribute ordering */
--
1.9.1