xref: /linux/net/smc/smc_loopback.h (revision c7546e2c3cb739a3c1a2f5acaf9bb629d401afe5)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  Shared Memory Communications Direct over loopback-ism device.
4  *
5  *  SMC-D loopback-ism device structure definitions.
6  *
7  *  Copyright (c) 2024, Alibaba Inc.
8  *
9  *  Author: Wen Gu <guwen@linux.alibaba.com>
10  *          Tony Lu <tonylu@linux.alibaba.com>
11  *
12  */
13 
14 #ifndef _SMC_LOOPBACK_H
15 #define _SMC_LOOPBACK_H
16 
17 #include <linux/device.h>
18 #include <net/smc.h>
19 
20 #if IS_ENABLED(CONFIG_SMC_LO)
21 #define SMC_LO_MAX_DMBS		5000
22 #define SMC_LO_DMBS_HASH_BITS	12
23 #define SMC_LO_RESERVED_CHID	0xFFFF
24 
25 struct smc_lo_dmb_node {
26 	struct hlist_node list;
27 	u64 token;
28 	u32 len;
29 	u32 sba_idx;
30 	void *cpu_addr;
31 	dma_addr_t dma_addr;
32 	refcount_t refcnt;
33 };
34 
35 struct smc_lo_dev {
36 	struct smcd_dev *smcd;
37 	struct device dev;
38 	u16 chid;
39 	struct smcd_gid local_gid;
40 	atomic_t dmb_cnt;
41 	rwlock_t dmb_ht_lock;
42 	DECLARE_BITMAP(sba_idx_mask, SMC_LO_MAX_DMBS);
43 	DECLARE_HASHTABLE(dmb_ht, SMC_LO_DMBS_HASH_BITS);
44 	wait_queue_head_t ldev_release;
45 };
46 
47 int smc_loopback_init(void);
48 void smc_loopback_exit(void);
49 #else
50 static inline int smc_loopback_init(void)
51 {
52 	return 0;
53 }
54 
55 static inline void smc_loopback_exit(void)
56 {
57 }
58 #endif
59 
60 #endif /* _SMC_LOOPBACK_H */
61