xref: /linux/net/smc/smc_loopback.h (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
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 <linux/err.h>
19 #include <net/smc.h>
20 
21 #if IS_ENABLED(CONFIG_SMC_LO)
22 #define SMC_LO_MAX_DMBS		5000
23 #define SMC_LO_DMBS_HASH_BITS	12
24 #define SMC_LO_RESERVED_CHID	0xFFFF
25 
26 struct smc_lo_dmb_node {
27 	struct hlist_node list;
28 	u64 token;
29 	u32 len;
30 	u32 sba_idx;
31 	void *cpu_addr;
32 	dma_addr_t dma_addr;
33 	refcount_t refcnt;
34 };
35 
36 struct smc_lo_dev {
37 	struct smcd_dev *smcd;
38 	struct device dev;
39 	u16 chid;
40 	struct smcd_gid local_gid;
41 	atomic_t dmb_cnt;
42 	rwlock_t dmb_ht_lock;
43 	DECLARE_BITMAP(sba_idx_mask, SMC_LO_MAX_DMBS);
44 	DECLARE_HASHTABLE(dmb_ht, SMC_LO_DMBS_HASH_BITS);
45 	wait_queue_head_t ldev_release;
46 };
47 
48 int smc_loopback_init(void);
49 void smc_loopback_exit(void);
50 #else
51 static inline int smc_loopback_init(void)
52 {
53 	return 0;
54 }
55 
56 static inline void smc_loopback_exit(void)
57 {
58 }
59 #endif
60 
61 #endif /* _SMC_LOOPBACK_H */
62