IB/mlx5, iser, isert: Add Signature API additions

Expose more signature setting parameters. We modify the signature API
to allow usage of some new execution parameters relevant to data
integrity feature.

This patch modifies ib_sig_domain structure by:

- Deprecate DIF type in signature API (operation will
  be determined by the parameters alone, no DIF type awareness)
- Add APPTAG check bitmask (for input domain)
- Add REFTAG remap (increment) flag for each domain
- Add APPTAG/REFTAG escape options for each domain

The mlx5 driver is modified to follow the new parameters in HW
signature setup.

At the moment the callers (iser/isert) hard-code new parameters (by
DIF type). In the future, callers will retrieve them from the scsi
command structure.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

4 files changed, 97 insertions, 129 deletions

diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index 13924a256290..d7f35e9e6522 100644
--- a/drivers/infiniband/hw/mlx5/qp.c
+++ b/drivers/infiniband/hw/mlx5/qp.c
@@ -2020,50 +2020,31 @@ static u8 bs_selector(int block_size)
         }
 }
 
-static int mlx5_fill_inl_bsf(struct ib_sig_domain *domain,
-                             struct mlx5_bsf_inl *inl)
+static void mlx5_fill_inl_bsf(struct ib_sig_domain *domain,
+                              struct mlx5_bsf_inl *inl)
 {
         /* Valid inline section and allow BSF refresh */
         inl->vld_refresh = cpu_to_be16(MLX5_BSF_INL_VALID |
                                        MLX5_BSF_REFRESH_DIF);
         inl->dif_apptag = cpu_to_be16(domain->sig.dif.app_tag);
         inl->dif_reftag = cpu_to_be32(domain->sig.dif.ref_tag);
+        /* repeating block */
+        inl->rp_inv_seed = MLX5_BSF_REPEAT_BLOCK;
+        inl->sig_type = domain->sig.dif.bg_type == IB_T10DIF_CRC ?
+                        MLX5_DIF_CRC : MLX5_DIF_IPCS;
 
-        switch (domain->sig.dif.type) {
-        case IB_T10DIF_NONE:
-                /* No DIF */
-                break;
-        case IB_T10DIF_TYPE1: /* Fall through */
-        case IB_T10DIF_TYPE2:
-                inl->sig_type = domain->sig.dif.bg_type == IB_T10DIF_CRC ?
-                                MLX5_DIF_CRC : MLX5_DIF_IPCS;
-                /*
-                 * increment reftag and don't check if
-                 * apptag=0xffff and reftag=0xffffffff
-                 */
-                inl->dif_inc_ref_guard_check = MLX5_BSF_INC_REFTAG |
-                                               MLX5_BSF_APPREF_ESCAPE;
-                inl->dif_app_bitmask_check = 0xffff;
-                /* repeating block */
-                inl->rp_inv_seed = MLX5_BSF_REPEAT_BLOCK;
-                break;
-        case IB_T10DIF_TYPE3:
-                inl->sig_type = domain->sig.dif.bg_type == IB_T10DIF_CRC ?
-                                MLX5_DIF_CRC : MLX5_DIF_IPCS;
-                /*
-                 * Don't inc reftag and don't check if
-                 * apptag=0xffff and reftag=0xffffffff
-                 */
-                inl->dif_inc_ref_guard_check = MLX5_BSF_APPREF_ESCAPE;
-                inl->dif_app_bitmask_check = 0xffff;
-                /* Repeating block */
-                inl->rp_inv_seed = MLX5_BSF_REPEAT_BLOCK;
-                break;
-        default:
-                return -EINVAL;
+        if (domain->sig.dif.ref_remap)
+                inl->dif_inc_ref_guard_check |= MLX5_BSF_INC_REFTAG;
+
+        if (domain->sig.dif.app_escape) {
+                if (domain->sig.dif.ref_escape)
+                        inl->dif_inc_ref_guard_check |= MLX5_BSF_APPREF_ESCAPE;
+                else
+                        inl->dif_inc_ref_guard_check |= MLX5_BSF_APPTAG_ESCAPE;
         }
 
-        return 0;
+        inl->dif_app_bitmask_check =
+                cpu_to_be16(domain->sig.dif.apptag_check_mask);
 }
 
 static int mlx5_set_bsf(struct ib_mr *sig_mr,
@@ -2074,20 +2055,35 @@ static int mlx5_set_bsf(struct ib_mr *sig_mr,
         struct mlx5_bsf_basic *basic = &bsf->basic;
         struct ib_sig_domain *mem = &sig_attrs->mem;
         struct ib_sig_domain *wire = &sig_attrs->wire;
-        int ret;
 
         memset(bsf, 0, sizeof(*bsf));
+
+        /* Basic + Extended + Inline */
+        basic->bsf_size_sbs = 1 << 7;
+        /* Input domain check byte mask */
+        basic->check_byte_mask = sig_attrs->check_mask;
+        basic->raw_data_size = cpu_to_be32(data_size);
+
+        /* Memory domain */
         switch (sig_attrs->mem.sig_type) {
+        case IB_SIG_TYPE_NONE:
+                break;
         case IB_SIG_TYPE_T10_DIF:
-                if (sig_attrs->wire.sig_type != IB_SIG_TYPE_T10_DIF)
-                        return -EINVAL;
+                basic->mem.bs_selector = bs_selector(mem->sig.dif.pi_interval);
+                basic->m_bfs_psv = cpu_to_be32(msig->psv_memory.psv_idx);
+                mlx5_fill_inl_bsf(mem, &bsf->m_inl);
+                break;
+        default:
+                return -EINVAL;
+        }
 
-                /* Basic + Extended + Inline */
-                basic->bsf_size_sbs = 1 << 7;
-                /* Input domain check byte mask */
-                basic->check_byte_mask = sig_attrs->check_mask;
+        /* Wire domain */
+        switch (sig_attrs->wire.sig_type) {
+        case IB_SIG_TYPE_NONE:
+                break;
+        case IB_SIG_TYPE_T10_DIF:
                 if (mem->sig.dif.pi_interval == wire->sig.dif.pi_interval &&
-                    mem->sig.dif.type == wire->sig.dif.type) {
+                    mem->sig_type == wire->sig_type) {
                         /* Same block structure */
                         basic->bsf_size_sbs |= 1 << 4;
                         if (mem->sig.dif.bg_type == wire->sig.dif.bg_type)
@@ -2099,20 +2095,9 @@ static int mlx5_set_bsf(struct ib_mr *sig_mr,
                 } else
                         basic->wire.bs_selector = bs_selector(wire->sig.dif.pi_interval);
 
-                basic->mem.bs_selector = bs_selector(mem->sig.dif.pi_interval);
-                basic->raw_data_size = cpu_to_be32(data_size);
-                basic->m_bfs_psv = cpu_to_be32(msig->psv_memory.psv_idx);
                 basic->w_bfs_psv = cpu_to_be32(msig->psv_wire.psv_idx);
-
-                ret = mlx5_fill_inl_bsf(wire, &bsf->w_inl);
-                if (ret)
-                        return -EINVAL;
-
-                ret = mlx5_fill_inl_bsf(mem, &bsf->m_inl);
-                if (ret)
-                        return -EINVAL;
+                mlx5_fill_inl_bsf(wire, &bsf->w_inl);
                 break;
-
         default:
                 return -EINVAL;
         }
@@ -2311,20 +2296,21 @@ static int set_psv_wr(struct ib_sig_domain *domain,
         memset(psv_seg, 0, sizeof(*psv_seg));
         psv_seg->psv_num = cpu_to_be32(psv_idx);
         switch (domain->sig_type) {
+        case IB_SIG_TYPE_NONE:
+                break;
         case IB_SIG_TYPE_T10_DIF:
                 psv_seg->transient_sig = cpu_to_be32(domain->sig.dif.bg << 16 |
                                                      domain->sig.dif.app_tag);
                 psv_seg->ref_tag = cpu_to_be32(domain->sig.dif.ref_tag);
-
-                *seg += sizeof(*psv_seg);
-                *size += sizeof(*psv_seg) / 16;
                 break;
-
         default:
                 pr_err("Bad signature type given.\n");
                 return 1;
         }
 
+        *seg += sizeof(*psv_seg);
+        *size += sizeof(*psv_seg) / 16;
+
         return 0;
 }
 
diff --git a/drivers/infiniband/ulp/iser/iser_memory.c b/drivers/infiniband/ulp/iser/iser_memory.c
index d9ed6234c505..6c5ce357fba6 100644
--- a/drivers/infiniband/ulp/iser/iser_memory.c
+++ b/drivers/infiniband/ulp/iser/iser_memory.c
@@ -440,51 +440,44 @@ int iser_reg_rdma_mem_fmr(struct iscsi_iser_task *iser_task,
         return 0;
 }
 
-static inline enum ib_t10_dif_type
-scsi2ib_prot_type(unsigned char prot_type)
-{
-        switch (prot_type) {
-        case SCSI_PROT_DIF_TYPE0:
-                return IB_T10DIF_NONE;
-        case SCSI_PROT_DIF_TYPE1:
-                return IB_T10DIF_TYPE1;
-        case SCSI_PROT_DIF_TYPE2:
-                return IB_T10DIF_TYPE2;
-        case SCSI_PROT_DIF_TYPE3:
-                return IB_T10DIF_TYPE3;
-        default:
-                return IB_T10DIF_NONE;
-        }
-}
-
 static inline void
 iser_set_dif_domain(struct scsi_cmnd *sc, struct ib_sig_attrs *sig_attrs,
                     struct ib_sig_domain *domain)
 {
-        unsigned char scsi_ptype = scsi_get_prot_type(sc);
-
-        domain->sig.dif.type = scsi2ib_prot_type(scsi_ptype);
+        domain->sig_type = IB_SIG_TYPE_T10_DIF;
         domain->sig.dif.pi_interval = sc->device->sector_size;
         domain->sig.dif.ref_tag = scsi_get_lba(sc) & 0xffffffff;
+        /*
+         * At the moment we hard code those, but in the future
+         * we will take them from sc.
+         */
+        domain->sig.dif.apptag_check_mask = 0xffff;
+        domain->sig.dif.app_escape = true;
+        domain->sig.dif.ref_escape = true;
+        if (scsi_get_prot_type(sc) == SCSI_PROT_DIF_TYPE1 ||
+            scsi_get_prot_type(sc) == SCSI_PROT_DIF_TYPE2)
+                domain->sig.dif.ref_remap = true;
 };
 
 static int
 iser_set_sig_attrs(struct scsi_cmnd *sc, struct ib_sig_attrs *sig_attrs)
 {
-        sig_attrs->mem.sig_type = IB_SIG_TYPE_T10_DIF;
-        sig_attrs->wire.sig_type = IB_SIG_TYPE_T10_DIF;
-
         switch (scsi_get_prot_op(sc)) {
         case SCSI_PROT_WRITE_INSERT:
         case SCSI_PROT_READ_STRIP:
-                sig_attrs->mem.sig.dif.type = IB_T10DIF_NONE;
+                sig_attrs->mem.sig_type = IB_SIG_TYPE_NONE;
                 iser_set_dif_domain(sc, sig_attrs, &sig_attrs->wire);
                 sig_attrs->wire.sig.dif.bg_type = IB_T10DIF_CRC;
                 break;
         case SCSI_PROT_READ_INSERT:
         case SCSI_PROT_WRITE_STRIP:
-                sig_attrs->wire.sig.dif.type = IB_T10DIF_NONE;
+                sig_attrs->wire.sig_type = IB_SIG_TYPE_NONE;
                 iser_set_dif_domain(sc, sig_attrs, &sig_attrs->mem);
+                /*
+                 * At the moment we use this modparam to tell what is
+                 * the memory bg_type, in the future we will take it
+                 * from sc.
+                 */
                 sig_attrs->mem.sig.dif.bg_type = iser_pi_guard ? IB_T10DIF_CSUM :
                                                  IB_T10DIF_CRC;
                 break;
@@ -493,6 +486,11 @@ iser_set_sig_attrs(struct scsi_cmnd *sc, struct ib_sig_attrs *sig_attrs)
                 iser_set_dif_domain(sc, sig_attrs, &sig_attrs->wire);
                 sig_attrs->wire.sig.dif.bg_type = IB_T10DIF_CRC;
                 iser_set_dif_domain(sc, sig_attrs, &sig_attrs->mem);
+                /*
+                 * At the moment we use this modparam to tell what is
+                 * the memory bg_type, in the future we will take it
+                 * from sc.
+                 */
                 sig_attrs->mem.sig.dif.bg_type = iser_pi_guard ? IB_T10DIF_CSUM :
                                                  IB_T10DIF_CRC;
                 break;
@@ -501,10 +499,10 @@ iser_set_sig_attrs(struct scsi_cmnd *sc, struct ib_sig_attrs *sig_attrs)
                          scsi_get_prot_op(sc));
                 return -EINVAL;
         }
+
         return 0;
 }
 
-
 static int
 iser_set_prot_checks(struct scsi_cmnd *sc, u8 *mask)
 {
diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c
index 73092756460b..0bea5776bcbc 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.c
+++ b/drivers/infiniband/ulp/isert/ib_isert.c
@@ -2609,51 +2609,39 @@ isert_fast_reg_mr(struct isert_conn *isert_conn,
         return ret;
 }
 
-static inline enum ib_t10_dif_type
-se2ib_prot_type(enum target_prot_type prot_type)
-{
-        switch (prot_type) {
-        case TARGET_DIF_TYPE0_PROT:
-                return IB_T10DIF_NONE;
-        case TARGET_DIF_TYPE1_PROT:
-                return IB_T10DIF_TYPE1;
-        case TARGET_DIF_TYPE2_PROT:
-                return IB_T10DIF_TYPE2;
-        case TARGET_DIF_TYPE3_PROT:
-                return IB_T10DIF_TYPE3;
-        default:
-                return IB_T10DIF_NONE;
-        }
-}
-
 static inline void
 isert_set_dif_domain(struct se_cmd *se_cmd, struct ib_sig_attrs *sig_attrs,
                      struct ib_sig_domain *domain)
 {
-        enum ib_t10_dif_type ib_prot_type = se2ib_prot_type(se_cmd->prot_type);
-
-        domain->sig.dif.type = ib_prot_type;
+        domain->sig_type = IB_SIG_TYPE_T10_DIF;
         domain->sig.dif.bg_type = IB_T10DIF_CRC;
         domain->sig.dif.pi_interval = se_cmd->se_dev->dev_attrib.block_size;
         domain->sig.dif.ref_tag = se_cmd->reftag_seed;
+        /*
+         * At the moment we hard code those, but if in the future
+         * the target core would like to use it, we will take it
+         * from se_cmd.
+         */
+        domain->sig.dif.apptag_check_mask = 0xffff;
+        domain->sig.dif.app_escape = true;
+        domain->sig.dif.ref_escape = true;
+        if (se_cmd->prot_type == TARGET_DIF_TYPE1_PROT ||
+            se_cmd->prot_type == TARGET_DIF_TYPE2_PROT)
+                domain->sig.dif.ref_remap = true;
 };
 
 static int
 isert_set_sig_attrs(struct se_cmd *se_cmd, struct ib_sig_attrs *sig_attrs)
 {
-
-        sig_attrs->mem.sig_type = IB_SIG_TYPE_T10_DIF;
-        sig_attrs->wire.sig_type = IB_SIG_TYPE_T10_DIF;
-
         switch (se_cmd->prot_op) {
         case TARGET_PROT_DIN_INSERT:
         case TARGET_PROT_DOUT_STRIP:
-                sig_attrs->mem.sig.dif.type = IB_T10DIF_NONE;
+                sig_attrs->mem.sig_type = IB_SIG_TYPE_NONE;
                 isert_set_dif_domain(se_cmd, sig_attrs, &sig_attrs->wire);
                 break;
         case TARGET_PROT_DOUT_INSERT:
         case TARGET_PROT_DIN_STRIP:
-                sig_attrs->wire.sig.dif.type = IB_T10DIF_NONE;
+                sig_attrs->wire.sig_type = IB_SIG_TYPE_NONE;
                 isert_set_dif_domain(se_cmd, sig_attrs, &sig_attrs->mem);
                 break;
         case TARGET_PROT_DIN_PASS:
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index ed44cc07a7b3..470a011d6fa4 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -491,20 +491,14 @@ struct ib_mr_init_attr {
         u32         flags;
 };
 
-enum ib_signature_type {
-        IB_SIG_TYPE_T10_DIF,
-};
-
 /**
- * T10-DIF Signature types
- * T10-DIF types are defined by SCSI
- * specifications.
+ * Signature types
+ * IB_SIG_TYPE_NONE: Unprotected.
+ * IB_SIG_TYPE_T10_DIF: Type T10-DIF
  */
-enum ib_t10_dif_type {
-        IB_T10DIF_NONE,
-        IB_T10DIF_TYPE1,
-        IB_T10DIF_TYPE2,
-        IB_T10DIF_TYPE3
+enum ib_signature_type {
+        IB_SIG_TYPE_NONE,
+        IB_SIG_TYPE_T10_DIF,
 };
 
 /**
@@ -520,24 +514,26 @@ enum ib_t10_dif_bg_type {
 /**
  * struct ib_t10_dif_domain - Parameters specific for T10-DIF
  *     domain.
- * @type: T10-DIF type (0|1|2|3)
  * @bg_type: T10-DIF block guard type (CRC|CSUM)
  * @pi_interval: protection information interval.
  * @bg: seed of guard computation.
  * @app_tag: application tag of guard block
  * @ref_tag: initial guard block reference tag.
- * @type3_inc_reftag: T10-DIF type 3 does not state
- *     about the reference tag, it is the user
- *     choice to increment it or not.
+ * @ref_remap: Indicate wethear the reftag increments each block
+ * @app_escape: Indicate to skip block check if apptag=0xffff
+ * @ref_escape: Indicate to skip block check if reftag=0xffffffff
+ * @apptag_check_mask: check bitmask of application tag.
  */
 struct ib_t10_dif_domain {
-        enum ib_t10_dif_type    type;
         enum ib_t10_dif_bg_type bg_type;
         u16                     pi_interval;
         u16                     bg;
         u16                     app_tag;
         u32                     ref_tag;
-        bool                    type3_inc_reftag;
+        bool                    ref_remap;
+        bool                    app_escape;
+        bool                    ref_escape;
+        u16                     apptag_check_mask;
 };
 
 /**