[SCSI] srp.h: avoid padding of structs
Several structs in <scsi/srp.h> get padded to a multiple of 8 bytes on
64-bit architectures and end up with a size that does not match the
definition in the SRP spec:
SRP spec 64-bit
sizeof (struct indirect_buf) 20 24
sizeof (struct srp_login_rsp) 52 56
sizeof (struct srp_rsp) 36 40
Fix this by adding __attribute__((packed)) to the offending structs.
Problem pointed out by Arne Redlich <arne.redlich@xiranet.com>.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/include/scsi/srp.h b/include/scsi/srp.h
index 6c2681d..637f77e 100644
--- a/include/scsi/srp.h
+++ b/include/scsi/srp.h
@@ -95,14 +95,15 @@
/*
* We need the packed attribute because the SRP spec puts the list of
- * descriptors at an offset of 20, which is not aligned to the size
- * of struct srp_direct_buf.
+ * descriptors at an offset of 20, which is not aligned to the size of
+ * struct srp_direct_buf. The whole structure must be packed to avoid
+ * having the 20-byte structure padded to 24 bytes on 64-bit architectures.
*/
struct srp_indirect_buf {
struct srp_direct_buf table_desc;
__be32 len;
- struct srp_direct_buf desc_list[0] __attribute__((packed));
-};
+ struct srp_direct_buf desc_list[0];
+} __attribute__((packed));
enum {
SRP_MULTICHAN_SINGLE = 0,
@@ -122,6 +123,11 @@
u8 target_port_id[16];
};
+/*
+ * The SRP spec defines the size of the LOGIN_RSP structure to be 52
+ * bytes, so it needs to be packed to avoid having it padded to 56
+ * bytes on 64-bit architectures.
+ */
struct srp_login_rsp {
u8 opcode;
u8 reserved1[3];
@@ -132,7 +138,7 @@
__be16 buf_fmt;
u8 rsp_flags;
u8 reserved2[25];
-};
+} __attribute__((packed));
struct srp_login_rej {
u8 opcode;
@@ -207,6 +213,11 @@
SRP_RSP_FLAG_DIUNDER = 1 << 5
};
+/*
+ * The SRP spec defines the size of the RSP structure to be 36 bytes,
+ * so it needs to be packed to avoid having it padded to 40 bytes on
+ * 64-bit architectures.
+ */
struct srp_rsp {
u8 opcode;
u8 sol_not;
@@ -221,6 +232,6 @@
__be32 sense_data_len;
__be32 resp_data_len;
u8 data[0];
-};
+} __attribute__((packed));
#endif /* SCSI_SRP_H */