net/mlx5: Add reserved-gids support

Reserved GIDs are entries in the GID table in use by the mlx5_core
and its submodules (e.g. FPGA, SRIOV, E-Swtich, netdev).
The entries are reserved at the high indexes of the GID table.

A mlx5 submodule may reserve a certain amount of GIDs for its own use
during the load sequence by calling mlx5_core_reserve_gids, and must
also take care to un-reserve these GIDs when it closes.
Reservation is only allowed during the load sequence and before any
interfaces (e.g. mlx5_ib or mlx5_en) are up.

After reservation, a submodule may call mlx5_core_reserved_gid_alloc/
free to allocate entries from the reserved GIDs pool.

Reserve a GID table entry for every supported FPGA QP.

A later patch in the patchset will remove them from being reported to
IB core.
Another such patch will make use of these for FPGA QPs in Innova NIC.

Added lib/mlx5.h to serve as a library for mlx5 submodlues, and to
expose only public mlx5 API, more mlx5 library files will be added in
future submissions.
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/Makefile

@@ -4,7 +4,7 @@ subdir-ccflags-y += -I$(src)
 mlx5_core-y :=	main.o cmd.o debugfs.o fw.o eq.o uar.o pagealloc.o \
 		health.o mcg.o cq.o srq.o alloc.o qp.o port.o mr.o pd.o \
 		mad.o transobj.o vport.o sriov.o fs_cmd.o fs_core.o \
-		fs_counters.o rl.o lag.o dev.o
+		fs_counters.o rl.o lag.o dev.o lib/gid.o
 
 mlx5_core-$(CONFIG_MLX5_FPGA) += fpga/cmd.o fpga/core.o
 

drivers/net/ethernet/mellanox/mlx5/core/fpga/core.c

@@ -35,6 +35,7 @@
 #include <linux/mlx5/driver.h>
 
 #include "mlx5_core.h"
+#include "lib/mlx5.h"
 #include "fpga/core.h"
 
 static const char *const mlx5_fpga_error_strings[] = {
@@ -104,6 +105,7 @@ int mlx5_fpga_device_start(struct mlx5_core_dev *mdev)
 {
 	struct mlx5_fpga_device *fdev = mdev->fpga;
 	unsigned long flags;
+	unsigned int max_num_qps;
 	int err;
 
 	if (!fdev)
@@ -123,6 +125,9 @@ int mlx5_fpga_device_start(struct mlx5_core_dev *mdev)
 		       mlx5_fpga_image_name(fdev->last_oper_image),
 		       MLX5_CAP_FPGA(fdev->mdev, image_version));
 
+	max_num_qps = MLX5_CAP_FPGA(mdev, shell_caps.max_num_qps);
+	err = mlx5_core_reserve_gids(mdev, max_num_qps);
+
 out:
 	spin_lock_irqsave(&fdev->state_lock, flags);
 	fdev->state = err ? MLX5_FPGA_STATUS_FAILURE : MLX5_FPGA_STATUS_SUCCESS;
@@ -151,9 +156,33 @@ int mlx5_fpga_device_init(struct mlx5_core_dev *mdev)
 	return 0;
 }
 
+void mlx5_fpga_device_stop(struct mlx5_core_dev *mdev)
+{
+	struct mlx5_fpga_device *fdev = mdev->fpga;
+	unsigned int max_num_qps;
+	unsigned long flags;
+
+	if (!fdev)
+		return;
+
+	spin_lock_irqsave(&fdev->state_lock, flags);
+	if (fdev->state != MLX5_FPGA_STATUS_SUCCESS) {
+		spin_unlock_irqrestore(&fdev->state_lock, flags);
+		return;
+	}
+	fdev->state = MLX5_FPGA_STATUS_NONE;
+	spin_unlock_irqrestore(&fdev->state_lock, flags);
+
+	max_num_qps = MLX5_CAP_FPGA(mdev, shell_caps.max_num_qps);
+	mlx5_core_unreserve_gids(mdev, max_num_qps);
+}
+
 void mlx5_fpga_device_cleanup(struct mlx5_core_dev *mdev)
 {
-	kfree(mdev->fpga);
+	struct mlx5_fpga_device *fdev = mdev->fpga;
+
+	mlx5_fpga_device_stop(mdev);
+	kfree(fdev);
 	mdev->fpga = NULL;
 }
 

drivers/net/ethernet/mellanox/mlx5/core/fpga/core.h

@@ -71,6 +71,7 @@ struct mlx5_fpga_device {
 int mlx5_fpga_device_init(struct mlx5_core_dev *mdev);
 void mlx5_fpga_device_cleanup(struct mlx5_core_dev *mdev);
 int mlx5_fpga_device_start(struct mlx5_core_dev *mdev);
+void mlx5_fpga_device_stop(struct mlx5_core_dev *mdev);
 void mlx5_fpga_event(struct mlx5_core_dev *mdev, u8 event, void *data);
 
 #else
@@ -89,6 +90,10 @@ static inline int mlx5_fpga_device_start(struct mlx5_core_dev *mdev)
 	return 0;
 }
 
+static inline void mlx5_fpga_device_stop(struct mlx5_core_dev *mdev)
+{
+}
+
 static inline void mlx5_fpga_event(struct mlx5_core_dev *mdev, u8 event,
 				   void *data)
 {

drivers/net/ethernet/mellanox/mlx5/core/lib/gid.c

+/*
+ * Copyright (c) 2017, Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/mlx5/driver.h>
+#include <linux/etherdevice.h>
+#include <linux/idr.h>
+#include "mlx5_core.h"
+
+void mlx5_init_reserved_gids(struct mlx5_core_dev *dev)
+{
+	unsigned int tblsz = MLX5_CAP_ROCE(dev, roce_address_table_size);
+
+	ida_init(&dev->roce.reserved_gids.ida);
+	dev->roce.reserved_gids.start = tblsz;
+	dev->roce.reserved_gids.count = 0;
+}
+
+void mlx5_cleanup_reserved_gids(struct mlx5_core_dev *dev)
+{
+	WARN_ON(!ida_is_empty(&dev->roce.reserved_gids.ida));
+	dev->roce.reserved_gids.start = 0;
+	dev->roce.reserved_gids.count = 0;
+	ida_destroy(&dev->roce.reserved_gids.ida);
+}
+
+int mlx5_core_reserve_gids(struct mlx5_core_dev *dev, unsigned int count)
+{
+	if (test_bit(MLX5_INTERFACE_STATE_UP, &dev->intf_state)) {
+		mlx5_core_err(dev, "Cannot reserve GIDs when interfaces are up\n");
+		return -EPERM;
+	}
+	if (dev->roce.reserved_gids.start < count) {
+		mlx5_core_warn(dev, "GID table exhausted attempting to reserve %d more GIDs\n",
+			       count);
+		return -ENOMEM;
+	}
+	if (dev->roce.reserved_gids.count + count > MLX5_MAX_RESERVED_GIDS) {
+		mlx5_core_warn(dev, "Unable to reserve %d more GIDs\n", count);
+		return -ENOMEM;
+	}
+
+	dev->roce.reserved_gids.start -= count;
+	dev->roce.reserved_gids.count += count;
+	mlx5_core_dbg(dev, "Reserved %u GIDs starting at %u\n",
+		      dev->roce.reserved_gids.count,
+		      dev->roce.reserved_gids.start);
+	return 0;
+}
+
+void mlx5_core_unreserve_gids(struct mlx5_core_dev *dev, unsigned int count)
+{
+	WARN(test_bit(MLX5_INTERFACE_STATE_UP, &dev->intf_state), "Unreserving GIDs when interfaces are up");
+	WARN(count > dev->roce.reserved_gids.count, "Unreserving %u GIDs when only %u reserved",
+	     count, dev->roce.reserved_gids.count);
+
+	dev->roce.reserved_gids.start += count;
+	dev->roce.reserved_gids.count -= count;
+	mlx5_core_dbg(dev, "%u GIDs starting at %u left reserved\n",
+		      dev->roce.reserved_gids.count,
+		      dev->roce.reserved_gids.start);
+}
+
+int mlx5_core_reserved_gid_alloc(struct mlx5_core_dev *dev, int *gid_index)
+{
+	int end = dev->roce.reserved_gids.start +
+		  dev->roce.reserved_gids.count;
+	int index = 0;
+
+	index = ida_simple_get(&dev->roce.reserved_gids.ida,
+			       dev->roce.reserved_gids.start, end,
+			       GFP_KERNEL);
+	if (index < 0)
+		return index;
+
+	mlx5_core_dbg(dev, "Allodating reserved GID %u\n", index);
+	*gid_index = index;
+	return 0;
+}
+
+void mlx5_core_reserved_gid_free(struct mlx5_core_dev *dev, int gid_index)
+{
+	mlx5_core_dbg(dev, "Freeing reserved GID %u\n", gid_index);
+	ida_simple_remove(&dev->roce.reserved_gids.ida, gid_index);
+}
+
+unsigned int mlx5_core_reserved_gids_count(struct mlx5_core_dev *dev)
+{
+	return dev->roce.reserved_gids.count;
+}
+EXPORT_SYMBOL_GPL(mlx5_core_reserved_gids_count);
+
+int mlx5_core_roce_gid_set(struct mlx5_core_dev *dev, unsigned int index,
+			   u8 roce_version, u8 roce_l3_type, const u8 *gid,
+			   const u8 *mac, bool vlan, u16 vlan_id)
+{
+#define MLX5_SET_RA(p, f, v) MLX5_SET(roce_addr_layout, p, f, v)
+	u32  in[MLX5_ST_SZ_DW(set_roce_address_in)] = {0};
+	u32 out[MLX5_ST_SZ_DW(set_roce_address_out)] = {0};
+	void *in_addr = MLX5_ADDR_OF(set_roce_address_in, in, roce_address);
+	char *addr_l3_addr = MLX5_ADDR_OF(roce_addr_layout, in_addr,
+					  source_l3_address);
+	void *addr_mac = MLX5_ADDR_OF(roce_addr_layout, in_addr,
+				      source_mac_47_32);
+	int gidsz = MLX5_FLD_SZ_BYTES(roce_addr_layout, source_l3_address);
+
+	if (MLX5_CAP_GEN(dev, port_type) != MLX5_CAP_PORT_TYPE_ETH)
+		return -EINVAL;
+
+	if (gid) {
+		if (vlan) {
+			MLX5_SET_RA(in_addr, vlan_valid, 1);
+			MLX5_SET_RA(in_addr, vlan_id, vlan_id);
+		}
+
+		ether_addr_copy(addr_mac, mac);
+		MLX5_SET_RA(in_addr, roce_version, roce_version);
+		MLX5_SET_RA(in_addr, roce_l3_type, roce_l3_type);
+		memcpy(addr_l3_addr, gid, gidsz);
+	}
+
+	MLX5_SET(set_roce_address_in, in, roce_address_index, index);
+	MLX5_SET(set_roce_address_in, in, opcode, MLX5_CMD_OP_SET_ROCE_ADDRESS);
+	return mlx5_cmd_exec(dev, in, sizeof(in), out, sizeof(out));
+}
+EXPORT_SYMBOL(mlx5_core_roce_gid_set);

drivers/net/ethernet/mellanox/mlx5/core/lib/mlx5.h

+/*
+ * Copyright (c) 2017, Mellanox Technologies, Ltd.  All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef __LIB_MLX5_H__
+#define __LIB_MLX5_H__
+
+void mlx5_init_reserved_gids(struct mlx5_core_dev *dev);
+void mlx5_cleanup_reserved_gids(struct mlx5_core_dev *dev);
+int  mlx5_core_reserve_gids(struct mlx5_core_dev *dev, unsigned int count);
+void mlx5_core_unreserve_gids(struct mlx5_core_dev *dev, unsigned int count);
+int  mlx5_core_reserved_gid_alloc(struct mlx5_core_dev *dev, int *gid_index);
+void mlx5_core_reserved_gid_free(struct mlx5_core_dev *dev, int gid_index);
+
+#endif

drivers/net/ethernet/mellanox/mlx5/core/main.c

@@ -56,6 +56,7 @@
 #ifdef CONFIG_MLX5_CORE_EN
 #include "eswitch.h"
 #endif
+#include "lib/mlx5.h"
 #include "fpga/core.h"
 
 MODULE_AUTHOR("Eli Cohen <eli@mellanox.com>");
@@ -936,6 +937,8 @@ static int mlx5_init_once(struct mlx5_core_dev *dev, struct mlx5_priv *priv)
 
 	mlx5_init_mkey_table(dev);
 
+	mlx5_init_reserved_gids(dev);
+
 	err = mlx5_init_rl_table(dev);
 	if (err) {
 		dev_err(&pdev->dev, "Failed to init rate limiting\n");
@@ -986,6 +989,7 @@ static void mlx5_cleanup_once(struct mlx5_core_dev *dev)
 	mlx5_eswitch_cleanup(dev->priv.eswitch);
 #endif
 	mlx5_cleanup_rl_table(dev);
+	mlx5_cleanup_reserved_gids(dev);
 	mlx5_cleanup_mkey_table(dev);
 	mlx5_cleanup_srq_table(dev);
 	mlx5_cleanup_qp_table(dev);
@@ -1160,7 +1164,7 @@ static int mlx5_load_one(struct mlx5_core_dev *dev, struct mlx5_priv *priv,
 	err = mlx5_fpga_device_start(dev);
 	if (err) {
 		dev_err(&pdev->dev, "fpga device start failed %d\n", err);
-		goto err_reg_dev;
+		goto err_fpga_start;
 	}
 
 	if (mlx5_device_registered(dev)) {
@@ -1181,6 +1185,9 @@ static int mlx5_load_one(struct mlx5_core_dev *dev, struct mlx5_priv *priv,
 	return 0;
 
 err_reg_dev:
+	mlx5_fpga_device_stop(dev);
+
+err_fpga_start:
 	mlx5_sriov_detach(dev);
 
 err_sriov:
@@ -1260,6 +1267,8 @@ static int mlx5_unload_one(struct mlx5_core_dev *dev, struct mlx5_priv *priv,
 	if (mlx5_device_registered(dev))
 		mlx5_detach_device(dev);
 
+	mlx5_fpga_device_stop(dev);
+
 	mlx5_sriov_detach(dev);
 #ifdef CONFIG_MLX5_CORE_EN
 	mlx5_eswitch_detach(dev->priv.eswitch);

include/linux/mlx5/driver.h

@@ -44,6 +44,7 @@
 #include <linux/workqueue.h>
 #include <linux/mempool.h>
 #include <linux/interrupt.h>
+#include <linux/idr.h>
 
 #include <linux/mlx5/device.h>
 #include <linux/mlx5/doorbell.h>
@@ -737,6 +738,14 @@ struct mlx5e_resources {
 	struct mlx5_sq_bfreg       bfreg;
 };
 
+#define MLX5_MAX_RESERVED_GIDS 8
+
+struct mlx5_rsvd_gids {
+	unsigned int start;
+	unsigned int count;
+	struct ida ida;
+};
+
 struct mlx5_core_dev {
 	struct pci_dev	       *pdev;
 	/* sync pci state */
@@ -766,6 +775,9 @@ struct mlx5_core_dev {
 	atomic_t		num_qps;
 	u32			issi;
 	struct mlx5e_resources  mlx5e_res;
+	struct {
+		struct mlx5_rsvd_gids	reserved_gids;
+	} roce;
 #ifdef CONFIG_MLX5_FPGA
 	struct mlx5_fpga_device *fpga;
 #endif
@@ -1045,6 +1057,11 @@ int mlx5_alloc_bfreg(struct mlx5_core_dev *mdev, struct mlx5_sq_bfreg *bfreg,
 		     bool map_wc, bool fast_path);
 void mlx5_free_bfreg(struct mlx5_core_dev *mdev, struct mlx5_sq_bfreg *bfreg);
 
+unsigned int mlx5_core_reserved_gids_count(struct mlx5_core_dev *dev);
+int mlx5_core_roce_gid_set(struct mlx5_core_dev *dev, unsigned int index,
+			   u8 roce_version, u8 roce_l3_type, const u8 *gid,
+			   const u8 *mac, bool vlan, u16 vlan_id);
+
 static inline int fw_initializing(struct mlx5_core_dev *dev)
 {
 	return ioread32be(&dev->iseg->initializing) >> 31;