[PATCH v3 10/17] net/mlx5_core: Add support for page faults events and low level handling

Haggai Eran
2014-12-11T15:04:19Z

* Add a handler function pointer in the mlx5_core_qp struct for page fault
events. Handle page fault events by calling the handler function, if not
NULL.
* Add on-demand paging capability query command.
* Export command for resuming QPs after page faults.
* Add various constants related to paging support.

Signed-off-by: Sagi Grimberg <sagig-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
Signed-off-by: Shachar Raindel <raindel-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
Signed-off-by: Haggai Eran <haggaie-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
---
drivers/net/ethernet/mellanox/mlx5/core/eq.c | 13 ++-
drivers/net/ethernet/mellanox/mlx5/core/fw.c | 40 +++++++++
drivers/net/ethernet/mellanox/mlx5/core/qp.c | 119 +++++++++++++++++++++++++++
include/linux/mlx5/device.h | 54 +++++++++++-
include/linux/mlx5/driver.h | 12 +++
include/linux/mlx5/qp.h | 55 +++++++++++++
6 files changed, 291 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eq.c b/drivers/net/ethernet/mellanox/mlx5/core/eq.c
index ad2c96a02a53..44cc16d4eff7 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eq.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eq.c
@@ -157,6 +157,8 @@ static const char *eqe_type_str(u8 type)
return "MLX5_EVENT_TYPE_CMD";
case MLX5_EVENT_TYPE_PAGE_REQUEST:
return "MLX5_EVENT_TYPE_PAGE_REQUEST";
+ case MLX5_EVENT_TYPE_PAGE_FAULT:
+ return "MLX5_EVENT_TYPE_PAGE_FAULT";
default:
return "Unrecognized event";
}
@@ -279,6 +281,11 @@ static int mlx5_eq_int(struct mlx5_core_dev *dev, struct mlx5_eq *eq)
}
break;

+#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
+ case MLX5_EVENT_TYPE_PAGE_FAULT:
+ mlx5_eq_pagefault(dev, eqe);
+ break;
+#endif

default:
mlx5_core_warn(dev, "Unhandled event 0x%x on EQ 0x%x\n",
@@ -446,8 +453,12 @@ void mlx5_eq_cleanup(struct mlx5_core_dev *dev)
int mlx5_start_eqs(struct mlx5_core_dev *dev)
{
struct mlx5_eq_table *table = &dev->priv.eq_table;
+ u32 async_event_mask = MLX5_ASYNC_EVENT_MASK;
int err;

+ if (dev->caps.gen.flags & MLX5_DEV_CAP_FLAG_ON_DMND_PG)
+ async_event_mask |= (1ull << MLX5_EVENT_TYPE_PAGE_FAULT);
+
err = mlx5_create_map_eq(dev, &table->cmd_eq, MLX5_EQ_VEC_CMD,
MLX5_NUM_CMD_EQE, 1ull << MLX5_EVENT_TYPE_CMD,
"mlx5_cmd_eq", &dev->priv.uuari.uars[0]);
@@ -459,7 +470,7 @@ int mlx5_start_eqs(struct mlx5_core_dev *dev)
mlx5_cmd_use_events(dev);

err = mlx5_create_map_eq(dev, &table->async_eq, MLX5_EQ_VEC_ASYNC,
- MLX5_NUM_ASYNC_EQE, MLX5_ASYNC_EVENT_MASK,
+ MLX5_NUM_ASYNC_EQE, async_event_mask,
"mlx5_async_eq", &dev->priv.uuari.uars[0]);
if (err) {
mlx5_core_warn(dev, "failed to create async EQ %d\n", err);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fw.c b/drivers/net/ethernet/mellanox/mlx5/core/fw.c
index 087c4c797deb..06f9036acd83 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/fw.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fw.c
@@ -69,6 +69,46 @@ int mlx5_cmd_query_hca_cap(struct mlx5_core_dev *dev, struct mlx5_caps *caps)
return mlx5_core_get_caps(dev, caps, HCA_CAP_OPMOD_GET_CUR);
}

+int mlx5_query_odp_caps(struct mlx5_core_dev *dev, struct mlx5_odp_caps *caps)
+{
+ u8 in[MLX5_ST_SZ_BYTES(query_hca_cap_in)];
+ int out_sz = MLX5_ST_SZ_BYTES(query_hca_cap_out);
+ void *out;
+ int err;
+
+ if (!(dev->caps.gen.flags & MLX5_DEV_CAP_FLAG_ON_DMND_PG))
+ return -ENOTSUPP;
+
+ memset(in, 0, sizeof(in));
+ out = kzalloc(out_sz, GFP_KERNEL);
+ if (!out)
+ return -ENOMEM;
+ MLX5_SET(query_hca_cap_in, in, opcode, MLX5_CMD_OP_QUERY_HCA_CAP);
+ MLX5_SET(query_hca_cap_in, in, op_mod, HCA_CAP_OPMOD_GET_ODP_CUR);
+ err = mlx5_cmd_exec(dev, in, sizeof(in), out, out_sz);
+ if (err)
+ goto out;
+
+ err = mlx5_cmd_status_to_err_v2(out);
+ if (err) {
+ mlx5_core_warn(dev, "query cur hca ODP caps failed, %d\n", err);
+ goto out;
+ }
+
+ memcpy(caps, MLX5_ADDR_OF(query_hca_cap_out, out, capability_struct),
+ sizeof(*caps));
+
+ mlx5_core_dbg(dev, "on-demand paging capabilities:\nrc: %08x\nuc: %08x\nud: %08x\n",
+ be32_to_cpu(caps->per_transport_caps.rc_odp_caps),
+ be32_to_cpu(caps->per_transport_caps.uc_odp_caps),
+ be32_to_cpu(caps->per_transport_caps.ud_odp_caps));
+
+out:
+ kfree(out);
+ return err;
+}
+EXPORT_SYMBOL(mlx5_query_odp_caps);
+
int mlx5_cmd_init_hca(struct mlx5_core_dev *dev)
{
struct mlx5_cmd_init_hca_mbox_in in;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/qp.c b/drivers/net/ethernet/mellanox/mlx5/core/qp.c
index 5261a2b0da43..575d853dbe05 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/qp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/qp.c
@@ -88,6 +88,95 @@ void mlx5_rsc_event(struct mlx5_core_dev *dev, u32 rsn, int event_type)
mlx5_core_put_rsc(common);
}

+#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
+void mlx5_eq_pagefault(struct mlx5_core_dev *dev, struct mlx5_eqe *eqe)
+{
+ struct mlx5_eqe_page_fault *pf_eqe = &eqe->data.page_fault;
+ int qpn = be32_to_cpu(pf_eqe->flags_qpn) & MLX5_QPN_MASK;
+ struct mlx5_core_rsc_common *common = mlx5_get_rsc(dev, qpn);
+ struct mlx5_core_qp *qp =
+ container_of(common, struct mlx5_core_qp, common);
+ struct mlx5_pagefault pfault;
+
+ if (!qp) {
+ mlx5_core_warn(dev, "ODP event for non-existent QP %06x\n",
+ qpn);
+ return;
+ }
+
+ pfault.event_subtype = eqe->sub_type;
+ pfault.flags = (be32_to_cpu(pf_eqe->flags_qpn) >> MLX5_QPN_BITS) &
+ (MLX5_PFAULT_REQUESTOR | MLX5_PFAULT_WRITE | MLX5_PFAULT_RDMA);
+ pfault.bytes_committed = be32_to_cpu(
+ pf_eqe->bytes_committed);
+
+ mlx5_core_dbg(dev,
+ "PAGE_FAULT: subtype: 0x%02x, flags: 0x%02x,\n",
+ eqe->sub_type, pfault.flags);
+
+ switch (eqe->sub_type) {
+ case MLX5_PFAULT_SUBTYPE_RDMA:
+ /* RDMA based event */
+ pfault.rdma.r_key =
+ be32_to_cpu(pf_eqe->rdma.r_key);
+ pfault.rdma.packet_size =
+ be16_to_cpu(pf_eqe->rdma.packet_length);
+ pfault.rdma.rdma_op_len =
+ be32_to_cpu(pf_eqe->rdma.rdma_op_len);
+ pfault.rdma.rdma_va =
+ be64_to_cpu(pf_eqe->rdma.rdma_va);
+ mlx5_core_dbg(dev,
+ "PAGE_FAULT: qpn: 0x%06x, r_key: 0x%08x,\n",
+ qpn, pfault.rdma.r_key);
+ mlx5_core_dbg(dev,
+ "PAGE_FAULT: rdma_op_len: 0x%08x,\n",
+ pfault.rdma.rdma_op_len);
+ mlx5_core_dbg(dev,
+ "PAGE_FAULT: rdma_va: 0x%016llx,\n",
+ pfault.rdma.rdma_va);
+ mlx5_core_dbg(dev,
+ "PAGE_FAULT: bytes_committed: 0x%06x\n",
+ pfault.bytes_committed);
+ break;
+
+ case MLX5_PFAULT_SUBTYPE_WQE:
+ /* WQE based event */
+ pfault.wqe.wqe_index =
+ be16_to_cpu(pf_eqe->wqe.wqe_index);
+ pfault.wqe.packet_size =
+ be16_to_cpu(pf_eqe->wqe.packet_length);
+ mlx5_core_dbg(dev,
+ "PAGE_FAULT: qpn: 0x%06x, wqe_index: 0x%04x,\n",
+ qpn, pfault.wqe.wqe_index);
+ mlx5_core_dbg(dev,
+ "PAGE_FAULT: bytes_committed: 0x%06x\n",
+ pfault.bytes_committed);
+ break;
+
+ default:
+ mlx5_core_warn(dev,
+ "Unsupported page fault event sub-type: 0x%02hhx, QP %06x\n",
+ eqe->sub_type, qpn);
+ /* Unsupported page faults should still be resolved by the
+ * page fault handler
+ */
+ }
+
+ if (qp->pfault_handler) {
+ qp->pfault_handler(qp, &pfault);
+ } else {
+ mlx5_core_err(dev,
+ "ODP event for QP %08x, without a fault handler in QP\n",
+ qpn);
+ /* Page fault will remain unresolved. QP will hang until it is
+ * destroyed
+ */
+ }
+
+ mlx5_core_put_rsc(common);
+}
+#endif
+
int mlx5_core_create_qp(struct mlx5_core_dev *dev,
struct mlx5_core_qp *qp,
struct mlx5_create_qp_mbox_in *in,
@@ -322,3 +411,33 @@ int mlx5_core_xrcd_dealloc(struct mlx5_core_dev *dev, u32 xrcdn)
return err;
}
EXPORT_SYMBOL_GPL(mlx5_core_xrcd_dealloc);
+
+#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
+int mlx5_core_page_fault_resume(struct mlx5_core_dev *dev, u32 qpn,
+ u8 flags, int error)
+{
+ struct mlx5_page_fault_resume_mbox_in in;
+ struct mlx5_page_fault_resume_mbox_out out;
+ int err;
+
+ memset(&in, 0, sizeof(in));
+ memset(&out, 0, sizeof(out));
+ in.hdr.opcode = cpu_to_be16(MLX5_CMD_OP_PAGE_FAULT_RESUME);
+ in.hdr.opmod = 0;
+ flags &= (MLX5_PAGE_FAULT_RESUME_REQUESTOR |
+ MLX5_PAGE_FAULT_RESUME_WRITE |
+ MLX5_PAGE_FAULT_RESUME_RDMA);
+ flags |= (error ? MLX5_PAGE_FAULT_RESUME_ERROR : 0);
+ in.flags_qpn = cpu_to_be32((qpn & MLX5_QPN_MASK) |
+ (flags << MLX5_QPN_BITS));
+ err = mlx5_cmd_exec(dev, &in, sizeof(in), &out, sizeof(out));
+ if (err)
+ return err;
+
+ if (out.hdr.status)
+ err = mlx5_cmd_status_to_err(&out.hdr);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(mlx5_core_page_fault_resume);
+#endif
diff --git a/include/linux/mlx5/device.h b/include/linux/mlx5/device.h
index 3562b9732699..ec7389fe4822 100644
--- a/include/linux/mlx5/device.h
+++ b/include/linux/mlx5/device.h
@@ -120,6 +120,15 @@ enum {
};

enum {
+ MLX5_MKEY_INBOX_PG_ACCESS = 1 << 31
+};
+
+enum {
+ MLX5_PFAULT_SUBTYPE_WQE = 0,
+ MLX5_PFAULT_SUBTYPE_RDMA = 1,
+};
+
+enum {
MLX5_PERM_LOCAL_READ = 1 << 2,
MLX5_PERM_LOCAL_WRITE = 1 << 3,
MLX5_PERM_REMOTE_READ = 1 << 4,
@@ -215,6 +224,8 @@ enum mlx5_event {

MLX5_EVENT_TYPE_CMD = 0x0a,
MLX5_EVENT_TYPE_PAGE_REQUEST = 0xb,
+
+ MLX5_EVENT_TYPE_PAGE_FAULT = 0xc,
};

enum {
@@ -307,6 +318,8 @@ enum {
enum {
HCA_CAP_OPMOD_GET_MAX = 0,
HCA_CAP_OPMOD_GET_CUR = 1,
+ HCA_CAP_OPMOD_GET_ODP_MAX = 4,
+ HCA_CAP_OPMOD_GET_ODP_CUR = 5
};

struct mlx5_inbox_hdr {
@@ -336,6 +349,23 @@ struct mlx5_cmd_query_adapter_mbox_out {
u8 vsd_psid[16];
};

+enum mlx5_odp_transport_cap_bits {
+ MLX5_ODP_SUPPORT_SEND = 1 << 31,
+ MLX5_ODP_SUPPORT_RECV = 1 << 30,
+ MLX5_ODP_SUPPORT_WRITE = 1 << 29,
+ MLX5_ODP_SUPPORT_READ = 1 << 28,
+};
+
+struct mlx5_odp_caps {
+ char reserved[0x10];
+ struct {
+ __be32 rc_odp_caps;
+ __be32 uc_odp_caps;
+ __be32 ud_odp_caps;
+ } per_transport_caps;
+ char reserved2[0xe4];
+};
+
struct mlx5_cmd_init_hca_mbox_in {
struct mlx5_inbox_hdr hdr;
u8 rsvd0[2];
@@ -456,6 +486,27 @@ struct mlx5_eqe_page_req {
__be32 rsvd1[5];
};

+struct mlx5_eqe_page_fault {
+ __be32 bytes_committed;
+ union {
+ struct {
+ u16 reserved1;
+ __be16 wqe_index;
+ u16 reserved2;
+ __be16 packet_length;
+ u8 reserved3[12];
+ } __packed wqe;
+ struct {
+ __be32 r_key;
+ u16 reserved1;
+ __be16 packet_length;
+ __be32 rdma_op_len;
+ __be64 rdma_va;
+ } __packed rdma;
+ } __packed;
+ __be32 flags_qpn;
+} __packed;
+
union ev_data {
__be32 raw[7];
struct mlx5_eqe_cmd cmd;
@@ -467,6 +518,7 @@ union ev_data {
struct mlx5_eqe_congestion cong;
struct mlx5_eqe_stall_vl stall_vl;
struct mlx5_eqe_page_req req_pages;
+ struct mlx5_eqe_page_fault page_fault;
} __packed;

struct mlx5_eqe {
@@ -833,7 +885,7 @@ struct mlx5_query_special_ctxs_mbox_out {
struct mlx5_create_mkey_mbox_in {
struct mlx5_inbox_hdr hdr;
__be32 input_mkey_index;
- u8 rsvd0[4];
+ __be32 flags;
struct mlx5_mkey_seg seg;
u8 rsvd1[16];
__be32 xlat_oct_act_size;
diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
index 246310dc8bef..09c707dec29a 100644
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -113,6 +113,13 @@ enum {
MLX5_REG_HOST_ENDIANNESS = 0x7004,
};

+enum mlx5_page_fault_resume_flags {
+ MLX5_PAGE_FAULT_RESUME_REQUESTOR = 1 << 0,
+ MLX5_PAGE_FAULT_RESUME_WRITE = 1 << 1,
+ MLX5_PAGE_FAULT_RESUME_RDMA = 1 << 2,
+ MLX5_PAGE_FAULT_RESUME_ERROR = 1 << 7,
+};
+
enum dbg_rsc_type {
MLX5_DBG_RSC_QP,
MLX5_DBG_RSC_EQ,
@@ -711,6 +718,9 @@ void mlx5_eq_cleanup(struct mlx5_core_dev *dev);
void mlx5_fill_page_array(struct mlx5_buf *buf, __be64 *pas);
void mlx5_cq_completion(struct mlx5_core_dev *dev, u32 cqn);
void mlx5_rsc_event(struct mlx5_core_dev *dev, u32 rsn, int event_type);
+#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
+void mlx5_eq_pagefault(struct mlx5_core_dev *dev, struct mlx5_eqe *eqe);
+#endif
void mlx5_srq_event(struct mlx5_core_dev *dev, u32 srqn, int event_type);
struct mlx5_core_srq *mlx5_core_get_srq(struct mlx5_core_dev *dev, u32 srqn);
void mlx5_cmd_comp_handler(struct mlx5_core_dev *dev, unsigned long vector);
@@ -748,6 +758,8 @@ int mlx5_core_create_psv(struct mlx5_core_dev *dev, u32 pdn,
int npsvs, u32 *sig_index);
int mlx5_core_destroy_psv(struct mlx5_core_dev *dev, int psv_num);
void mlx5_core_put_rsc(struct mlx5_core_rsc_common *common);
+int mlx5_query_odp_caps(struct mlx5_core_dev *dev,
+ struct mlx5_odp_caps *odp_caps);

static inline u32 mlx5_mkey_to_idx(u32 mkey)
{
diff --git a/include/linux/mlx5/qp.h b/include/linux/mlx5/qp.h
index 67f4b9660b06..6b1d6f60c7e6 100644
--- a/include/linux/mlx5/qp.h
+++ b/include/linux/mlx5/qp.h
@@ -50,6 +50,9 @@
#define MLX5_BSF_APPTAG_ESCAPE 0x1
#define MLX5_BSF_APPREF_ESCAPE 0x2

+#define MLX5_QPN_BITS 24
+#define MLX5_QPN_MASK ((1 << MLX5_QPN_BITS) - 1)
+
enum mlx5_qp_optpar {
MLX5_QP_OPTPAR_ALT_ADDR_PATH = 1 << 0,
MLX5_QP_OPTPAR_RRE = 1 << 1,
@@ -363,9 +366,46 @@ struct mlx5_stride_block_ctrl_seg {
__be16 num_entries;
};

+enum mlx5_pagefault_flags {
+ MLX5_PFAULT_REQUESTOR = 1 << 0,
+ MLX5_PFAULT_WRITE = 1 << 1,
+ MLX5_PFAULT_RDMA = 1 << 2,
+};
+
+/* Contains the details of a pagefault. */
+struct mlx5_pagefault {
+ u32 bytes_committed;
+ u8 event_subtype;
+ enum mlx5_pagefault_flags flags;
+ union {
+ /* Initiator or send message responder pagefault details. */
+ struct {
+ /* Received packet size, only valid for responders. */
+ u32 packet_size;
+ /*
+ * WQE index. Refers to either the send queue or
+ * receive queue, according to event_subtype.
+ */
+ u16 wqe_index;
+ } wqe;
+ /* RDMA responder pagefault details */
+ struct {
+ u32 r_key;
+ /*
+ * Received packet size, minimal size page fault
+ * resolution required for forward progress.
+ */
+ u32 packet_size;
+ u32 rdma_op_len;
+ u64 rdma_va;
+ } rdma;
+ };
+};
+
struct mlx5_core_qp {
struct mlx5_core_rsc_common common; /* must be first */
void (*event) (struct mlx5_core_qp *, int);
+ void (*pfault_handler)(struct mlx5_core_qp *, struct mlx5_pagefault *);
int qpn;
struct mlx5_rsc_debug *dbg;
int pid;
@@ -533,6 +573,17 @@ static inline struct mlx5_core_mr *__mlx5_mr_lookup(struct mlx5_core_dev *dev, u
return radix_tree_lookup(&dev->priv.mr_table.tree, key);
}

+struct mlx5_page_fault_resume_mbox_in {
+ struct mlx5_inbox_hdr hdr;
+ __be32 flags_qpn;
+ u8 reserved[4];
+};
+
+struct mlx5_page_fault_resume_mbox_out {
+ struct mlx5_outbox_hdr hdr;
+ u8 rsvd[8];
+};
+
int mlx5_core_create_qp(struct mlx5_core_dev *dev,
struct mlx5_core_qp *qp,
struct mlx5_create_qp_mbox_in *in,
@@ -552,6 +603,10 @@ void mlx5_init_qp_table(struct mlx5_core_dev *dev);
void mlx5_cleanup_qp_table(struct mlx5_core_dev *dev);
int mlx5_debug_qp_add(struct mlx5_core_dev *dev, struct mlx5_core_qp *qp);
void mlx5_debug_qp_remove(struct mlx5_core_dev *dev, struct mlx5_core_qp *qp);
+#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
+int mlx5_core_page_fault_resume(struct mlx5_core_dev *dev, u32 qpn,
+ u8 context, int error);
+#endif

static inline const char *mlx5_qp_type_str(int type)
{