| Message ID | 20210510040817.2050266-1-linux@roeck-us.net (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | scsi: target: iscsi: Drop unnecessary container_of | expand |
Guenter, > The structure pointer passed to container_of() is never NULL; that was > already checked. That means that the result of container_of() > operations on it is also never NULL, even though se_node_acl is the > first element of the structure embedding it. On top of that, it is > misleading to perform a NULL check on the result of container_of() > because the position of the contained element could change, which > would make the test invalid. Remove the unnecessary NULL check. Applied to 5.14/scsi-staging, thanks!
diff --git a/drivers/target/iscsi/iscsi_target_nego.c b/drivers/target/iscsi/iscsi_target_nego.c index 151e2949bb75..fb1b5816a5b6 100644 --- a/drivers/target/iscsi/iscsi_target_nego.c +++ b/drivers/target/iscsi/iscsi_target_nego.c @@ -118,13 +118,6 @@ static u32 iscsi_handle_authentication( " CHAP auth\n"); return -1; } - iscsi_nacl = container_of(se_nacl, struct iscsi_node_acl, - se_node_acl); - if (!iscsi_nacl) { - pr_err("Unable to locate struct iscsi_node_acl for" - " CHAP auth\n"); - return -1; - } if (se_nacl->dynamic_node_acl) { iscsi_tpg = container_of(se_nacl->se_tpg,
The structure pointer passed to container_of() is never NULL; that was already checked. That means that the result of container_of() operations on it is also never NULL, even though se_node_acl is the first element of the structure embedding it. On top of that, it is misleading to perform a NULL check on the result of container_of() because the position of the contained element could change, which would make the test invalid. Remove the unnecessary NULL check. As it turns out, the container_of operation was only made for the purpose of the NULL check. If the container_of is actually needed, it is repeated later. Remove the container_of operation as well. The NULL check was identified and removed with the following Coccinelle script. @@ type t; identifier v; statement s; @@ <+... ( t v = container_of(...); | v = container_of(...); ) ... when != v - if (\( !v \| v == NULL \) ) s ...+> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Hou Pu <houpu@bytedance.com> Cc: Mike Christie <michael.christie@oracle.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> --- drivers/target/iscsi/iscsi_target_nego.c | 7 ------- 1 file changed, 7 deletions(-)