Merge branch 's390-ism-generalized-interface'

Jan Karcher says:

====================
drivers/s390/net/ism: Add generalized interface

Previously, there was no clean separation between SMC-D code and the ISM
device driver.This patch series addresses the situation to make ISM available
for uses outside of SMC-D.
In detail: SMC-D offers an interface via struct smcd_ops, which only the
ISM module implements so far. However, there is no real separation between
the smcd and ism modules, which starts right with the ISM device
initialization, which calls directly into the SMC-D code.
This patch series introduces a new API in the ISM module, which allows
registration of arbitrary clients via include/linux/ism.h: struct ism_client.
Furthermore, it introduces a "pure" struct ism_dev (i.e. getting rid of
dependencies on SMC-D in the device structure), and adds a number of API
calls for data transfers via ISM (see ism_register_dmb() & friends).
Still, the ISM module implements the SMC-D API, and therefore has a number
of internal helper functions for that matter.
Note that the ISM API is consciously kept thin for now (as compared to the
SMC-D API calls), as a number of API calls are only used with SMC-D and
hardly have any meaningful usage beyond SMC-D, e.g. the VLAN-related calls.

v1 -> v2:
  Removed s390x dependency which broke config for other archs.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 98 insertions, 0 deletions

diff --git a/include/linux/ism.h b/include/linux/ism.h
new file mode 100644
index 000000000000..ea2bcdae7401
--- /dev/null
+++ b/include/linux/ism.h
@@ -0,0 +1,98 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ *  Internal Shared Memory
+ *
+ *  Definitions for the ISM module
+ *
+ *  Copyright IBM Corp. 2022
+ */
+#ifndef _ISM_H
+#define _ISM_H
+
+#include <linux/workqueue.h>
+
+struct ism_dmb {
+	u64 dmb_tok;
+	u64 rgid;
+	u32 dmb_len;
+	u32 sba_idx;
+	u32 vlan_valid;
+	u32 vlan_id;
+	void *cpu_addr;
+	dma_addr_t dma_addr;
+};
+
+/* Unless we gain unexpected popularity, this limit should hold for a while */
+#define MAX_CLIENTS		8
+#define ISM_NR_DMBS		1920
+
+struct ism_dev {
+	spinlock_t lock; /* protects the ism device */
+	struct list_head list;
+	struct pci_dev *pdev;
+
+	struct ism_sba *sba;
+	dma_addr_t sba_dma_addr;
+	DECLARE_BITMAP(sba_bitmap, ISM_NR_DMBS);
+	u8 *sba_client_arr;	/* entries are indices into 'clients' array */
+	void *priv[MAX_CLIENTS];
+
+	struct ism_eq *ieq;
+	dma_addr_t ieq_dma_addr;
+
+	struct device dev;
+	u64 local_gid;
+	int ieq_idx;
+
+	atomic_t free_clients_cnt;
+	atomic_t add_dev_cnt;
+	wait_queue_head_t waitq;
+};
+
+struct ism_event {
+	u32 type;
+	u32 code;
+	u64 tok;
+	u64 time;
+	u64 info;
+};
+
+struct ism_client {
+	const char *name;
+	void (*add)(struct ism_dev *dev);
+	void (*remove)(struct ism_dev *dev);
+	void (*handle_event)(struct ism_dev *dev, struct ism_event *event);
+	/* Parameter dmbemask contains a bit vector with updated DMBEs, if sent
+	 * via ism_move_data(). Callback function must handle all active bits
+	 * indicated by dmbemask.
+	 */
+	void (*handle_irq)(struct ism_dev *dev, unsigned int bit, u16 dmbemask);
+	/* Private area - don't touch! */
+	struct work_struct remove_work;
+	struct work_struct add_work;
+	struct ism_dev *tgt_ism;
+	u8 id;
+};
+
+int ism_register_client(struct ism_client *client);
+int  ism_unregister_client(struct ism_client *client);
+static inline void *ism_get_priv(struct ism_dev *dev,
+				 struct ism_client *client) {
+	return dev->priv[client->id];
+}
+
+static inline void ism_set_priv(struct ism_dev *dev, struct ism_client *client,
+				void *priv) {
+	dev->priv[client->id] = priv;
+}
+
+int  ism_register_dmb(struct ism_dev *dev, struct ism_dmb *dmb,
+		      struct ism_client *client);
+int  ism_unregister_dmb(struct ism_dev *dev, struct ism_dmb *dmb);
+int  ism_move(struct ism_dev *dev, u64 dmb_tok, unsigned int idx, bool sf,
+	      unsigned int offset, void *data, unsigned int size);
+u8  *ism_get_seid(void);
+
+const struct smcd_ops *ism_get_smcd_ops(void);
+
+#endif	/* _ISM_H */