From 8574cf4055ab44724ee9a4c30921d3ed853d787c Mon Sep 17 00:00:00 2001 From: Karsten Graul Date: Fri, 1 May 2020 12:48:12 +0200 Subject: net/smc: allocate index for a new link Add smc_llc_alloc_alt_link() to find a free link index for a new link, depending on the new link group type. And update constants for the maximum number of links to 3 (2 symmetric and 1 dangling asymmetric link). These maximum numbers are the same as used by other implementations of the SMC-R protocol. Signed-off-by: Karsten Graul Reviewed-by: Ursula Braun Signed-off-by: David S. Miller --- net/smc/smc_core.h | 2 +- net/smc/smc_llc.c | 24 ++++++++++++++++++++++++ 2 files changed, 25 insertions(+), 1 deletion(-) (limited to 'net/smc') diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h index da3cddbd1651..eb27f2eb7c8c 100644 --- a/net/smc/smc_core.h +++ b/net/smc/smc_core.h @@ -128,7 +128,7 @@ struct smc_link { /* For now we just allow one parallel link per link group. The SMC protocol * allows more (up to 8). */ -#define SMC_LINKS_PER_LGR_MAX 1 +#define SMC_LINKS_PER_LGR_MAX 3 #define SMC_SINGLE_LINK 0 #define SMC_FIRST_CONTACT 1 /* first contact to a peer */ diff --git a/net/smc/smc_llc.c b/net/smc/smc_llc.c index e478a4c11877..3a25b6ebe3a8 100644 --- a/net/smc/smc_llc.c +++ b/net/smc/smc_llc.c @@ -541,6 +541,30 @@ static int smc_llc_send_message(struct smc_link *link, void *llcbuf) /********************************* receive ***********************************/ +static int smc_llc_alloc_alt_link(struct smc_link_group *lgr, + enum smc_lgr_type lgr_new_t) +{ + int i; + + if (lgr->type == SMC_LGR_SYMMETRIC || + (lgr->type != SMC_LGR_SINGLE && + (lgr_new_t == SMC_LGR_ASYMMETRIC_LOCAL || + lgr_new_t == SMC_LGR_ASYMMETRIC_PEER))) + return -EMLINK; + + if (lgr_new_t == SMC_LGR_ASYMMETRIC_LOCAL || + lgr_new_t == SMC_LGR_ASYMMETRIC_PEER) { + for (i = SMC_LINKS_PER_LGR_MAX - 1; i >= 0; i--) + if (lgr->lnk[i].state == SMC_LNK_UNUSED) + return i; + } else { + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) + if (lgr->lnk[i].state == SMC_LNK_UNUSED) + return i; + } + return -EMLINK; +} + static void smc_llc_rx_delete_link(struct smc_link *link, struct smc_llc_msg_del_link *llc) { -- cgit v1.2.3