net/smc/smc_loopback.h

   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 */