IB: split struct ib_send_wr

This patch split up struct ib_send_wr so that all non-trivial verbs
use their own structure which embedds struct ib_send_wr.  This dramaticly
shrinks the size of a WR for most common operations:

sizeof(struct ib_send_wr) (old):	96

sizeof(struct ib_send_wr):		48
sizeof(struct ib_rdma_wr):		64
sizeof(struct ib_atomic_wr):		96
sizeof(struct ib_ud_wr):		88
sizeof(struct ib_fast_reg_wr):		88
sizeof(struct ib_bind_mw_wr):		96
sizeof(struct ib_sig_handover_wr):	80

And with Sagi's pending MR rework the fast registration WR will also be
down to a reasonable size:

sizeof(struct ib_fastreg_wr):		64

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> [srp, srpt]
Reviewed-by: Chuck Lever <chuck.lever@oracle.com> [sunrpc]
Tested-by: Haggai Eran <haggaie@mellanox.com>
Tested-by: Sagi Grimberg <sagig@mellanox.com>
Tested-by: Steve Wise <swise@opengridcomputing.com>

1 files changed, 85 insertions, 45 deletions

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 7845fae6f2df..25f022c9aaac 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -1100,54 +1100,94 @@ struct ib_send_wr {
                 __be32          imm_data;
                 u32             invalidate_rkey;
         } ex;
-        union {
-                struct {
-                        u64     remote_addr;
-                        u32     rkey;
-                } rdma;
-                struct {
-                        u64     remote_addr;
-                        u64     compare_add;
-                        u64     swap;
-                        u64     compare_add_mask;
-                        u64     swap_mask;
-                        u32     rkey;
-                } atomic;
-                struct {
-                        struct ib_ah *ah;
-                        void   *header;
-                        int     hlen;
-                        int     mss;
-                        u32     remote_qpn;
-                        u32     remote_qkey;
-                        u16     pkey_index; /* valid for GSI only */
-                        u8      port_num;   /* valid for DR SMPs on switch only */
-                } ud;
-                struct {
-                        u64                             iova_start;
-                        struct ib_fast_reg_page_list   *page_list;
-                        unsigned int                    page_shift;
-                        unsigned int                    page_list_len;
-                        u32                             length;
-                        int                             access_flags;
-                        u32                             rkey;
-                } fast_reg;
-                struct {
-                        struct ib_mw            *mw;
-                        /* The new rkey for the memory window. */
-                        u32                      rkey;
-                        struct ib_mw_bind_info   bind_info;
-                } bind_mw;
-                struct {
-                        struct ib_sig_attrs    *sig_attrs;
-                        struct ib_mr           *sig_mr;
-                        int                     access_flags;
-                        struct ib_sge          *prot;
-                } sig_handover;
-        } wr;
         u32                     xrc_remote_srq_num;     /* XRC TGT QPs only */
 };
 
+struct ib_rdma_wr {
+        struct ib_send_wr       wr;
+        u64                     remote_addr;
+        u32                     rkey;
+};
+
+static inline struct ib_rdma_wr *rdma_wr(struct ib_send_wr *wr)
+{
+        return container_of(wr, struct ib_rdma_wr, wr);
+}
+
+struct ib_atomic_wr {
+        struct ib_send_wr       wr;
+        u64                     remote_addr;
+        u64                     compare_add;
+        u64                     swap;
+        u64                     compare_add_mask;
+        u64                     swap_mask;
+        u32                     rkey;
+};
+
+static inline struct ib_atomic_wr *atomic_wr(struct ib_send_wr *wr)
+{
+        return container_of(wr, struct ib_atomic_wr, wr);
+}
+
+struct ib_ud_wr {
+        struct ib_send_wr       wr;
+        struct ib_ah            *ah;
+        void                    *header;
+        int                     hlen;
+        int                     mss;
+        u32                     remote_qpn;
+        u32                     remote_qkey;
+        u16                     pkey_index; /* valid for GSI only */
+        u8                      port_num;   /* valid for DR SMPs on switch only */
+};
+
+static inline struct ib_ud_wr *ud_wr(struct ib_send_wr *wr)
+{
+        return container_of(wr, struct ib_ud_wr, wr);
+}
+
+struct ib_fast_reg_wr {
+        struct ib_send_wr       wr;
+        u64                     iova_start;
+        struct ib_fast_reg_page_list *page_list;
+        unsigned int            page_shift;
+        unsigned int            page_list_len;
+        u32                     length;
+        int                     access_flags;
+        u32                     rkey;
+};
+
+static inline struct ib_fast_reg_wr *fast_reg_wr(struct ib_send_wr *wr)
+{
+        return container_of(wr, struct ib_fast_reg_wr, wr);
+}
+
+struct ib_bind_mw_wr {
+        struct ib_send_wr       wr;
+        struct ib_mw            *mw;
+        /* The new rkey for the memory window. */
+        u32                     rkey;
+        struct ib_mw_bind_info  bind_info;
+};
+
+static inline struct ib_bind_mw_wr *bind_mw_wr(struct ib_send_wr *wr)
+{
+        return container_of(wr, struct ib_bind_mw_wr, wr);
+}
+
+struct ib_sig_handover_wr {
+        struct ib_send_wr       wr;
+        struct ib_sig_attrs    *sig_attrs;
+        struct ib_mr           *sig_mr;
+        int                     access_flags;
+        struct ib_sge          *prot;
+};
+
+static inline struct ib_sig_handover_wr *sig_handover_wr(struct ib_send_wr *wr)
+{
+        return container_of(wr, struct ib_sig_handover_wr, wr);
+}
+
 struct ib_recv_wr {
         struct ib_recv_wr      *next;
         u64                     wr_id;