wifi: mac80211: move code in ieee80211_link_reserve_chanctx to a helper

Reduces indentation in preparation for further changes

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://patch.msgid.link/cce95007092336254d51570f4a27e05a6f150a53.1720514221.git-series.nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index 12bad02da561530c8541c61f8784436de55979b3..9aa3b9e2522817844f9070d4b3c06967d889e602 100644 (file)
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -1089,6 +1089,71 @@ int ieee80211_link_unreserve_chanctx(struct ieee80211_link_data *link)
        return 0;
 }
 
+static struct ieee80211_chanctx *
+ieee80211_replace_chanctx(struct ieee80211_local *local,
+                         const struct ieee80211_chan_req *chanreq,
+                         enum ieee80211_chanctx_mode mode,
+                         struct ieee80211_chanctx *curr_ctx)
+{
+       struct ieee80211_chanctx *new_ctx, *ctx;
+
+       if (!curr_ctx || (curr_ctx->replace_state ==
+                         IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
+           !list_empty(&curr_ctx->reserved_links)) {
+               /*
+                * Another link already requested this context for a
+                * reservation. Find another one hoping all links assigned
+                * to it will also switch soon enough.
+                *
+                * TODO: This needs a little more work as some cases
+                * (more than 2 chanctx capable devices) may fail which could
+                * otherwise succeed provided some channel context juggling was
+                * performed.
+                *
+                * Consider ctx1..3, link1..6, each ctx has 2 links. link1 and
+                * link2 from ctx1 request new different chandefs starting 2
+                * in-place reserations with ctx4 and ctx5 replacing ctx1 and
+                * ctx2 respectively. Next link5 and link6 from ctx3 reserve
+                * ctx4. If link3 and link4 remain on ctx2 as they are then this
+                * fails unless `replace_ctx` from ctx5 is replaced with ctx3.
+                */
+               list_for_each_entry(ctx, &local->chanctx_list, list) {
+                       if (ctx->replace_state !=
+                           IEEE80211_CHANCTX_REPLACE_NONE)
+                               continue;
+
+                       if (!list_empty(&ctx->reserved_links))
+                               continue;
+
+                       curr_ctx = ctx;
+                       break;
+               }
+       }
+
+       /*
+        * If that's true then all available contexts already have reservations
+        * and cannot be used.
+        */
+       if (!curr_ctx || (curr_ctx->replace_state ==
+                         IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
+           !list_empty(&curr_ctx->reserved_links))
+               return ERR_PTR(-EBUSY);
+
+       new_ctx = ieee80211_alloc_chanctx(local, chanreq, mode, -1);
+       if (!new_ctx)
+               return ERR_PTR(-ENOMEM);
+
+       new_ctx->replace_ctx = curr_ctx;
+       new_ctx->replace_state = IEEE80211_CHANCTX_REPLACES_OTHER;
+
+       curr_ctx->replace_ctx = new_ctx;
+       curr_ctx->replace_state = IEEE80211_CHANCTX_WILL_BE_REPLACED;
+
+       list_add_rcu(&new_ctx->list, &local->chanctx_list);
+
+       return new_ctx;
+}
+
 int ieee80211_link_reserve_chanctx(struct ieee80211_link_data *link,
                                   const struct ieee80211_chan_req *chanreq,
                                   enum ieee80211_chanctx_mode mode,
@@ -1096,7 +1161,7 @@ int ieee80211_link_reserve_chanctx(struct ieee80211_link_data *link,
 {
        struct ieee80211_sub_if_data *sdata = link->sdata;
        struct ieee80211_local *local = sdata->local;
-       struct ieee80211_chanctx *new_ctx, *curr_ctx, *ctx;
+       struct ieee80211_chanctx *new_ctx, *curr_ctx;
 
        lockdep_assert_wiphy(local->hw.wiphy);
 
@@ -1106,76 +1171,14 @@ int ieee80211_link_reserve_chanctx(struct ieee80211_link_data *link,
 
        new_ctx = ieee80211_find_reservation_chanctx(local, chanreq, mode);
        if (!new_ctx) {
-               if (ieee80211_can_create_new_chanctx(local, -1)) {
+               if (ieee80211_can_create_new_chanctx(local, -1))
                        new_ctx = ieee80211_new_chanctx(local, chanreq, mode,
                                                        false);
-                       if (IS_ERR(new_ctx))
-                               return PTR_ERR(new_ctx);
-               } else {
-                       if (!curr_ctx ||
-                           (curr_ctx->replace_state ==
-                            IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
-                           !list_empty(&curr_ctx->reserved_links)) {
-                               /*
-                                * Another link already requested this context
-                                * for a reservation. Find another one hoping
-                                * all links assigned to it will also switch
-                                * soon enough.
-                                *
-                                * TODO: This needs a little more work as some
-                                * cases (more than 2 chanctx capable devices)
-                                * may fail which could otherwise succeed
-                                * provided some channel context juggling was
-                                * performed.
-                                *
-                                * Consider ctx1..3, link1..6, each ctx has 2
-                                * links. link1 and link2 from ctx1 request new
-                                * different chandefs starting 2 in-place
-                                * reserations with ctx4 and ctx5 replacing
-                                * ctx1 and ctx2 respectively. Next link5 and
-                                * link6 from ctx3 reserve ctx4. If link3 and
-                                * link4 remain on ctx2 as they are then this
-                                * fails unless `replace_ctx` from ctx5 is
-                                * replaced with ctx3.
-                                */
-                               list_for_each_entry(ctx, &local->chanctx_list,
-                                                   list) {
-                                       if (ctx->replace_state !=
-                                           IEEE80211_CHANCTX_REPLACE_NONE)
-                                               continue;
-
-                                       if (!list_empty(&ctx->reserved_links))
-                                               continue;
-
-                                       curr_ctx = ctx;
-                                       break;
-                               }
-                       }
-
-                       /*
-                        * If that's true then all available contexts already
-                        * have reservations and cannot be used.
-                        */
-                       if (!curr_ctx ||
-                           (curr_ctx->replace_state ==
-                            IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
-                           !list_empty(&curr_ctx->reserved_links))
-                               return -EBUSY;
-
-                       new_ctx = ieee80211_alloc_chanctx(local, chanreq, mode, -1);
-                       if (!new_ctx)
-                               return -ENOMEM;
-
-                       new_ctx->replace_ctx = curr_ctx;
-                       new_ctx->replace_state =
-                                       IEEE80211_CHANCTX_REPLACES_OTHER;
-
-                       curr_ctx->replace_ctx = new_ctx;
-                       curr_ctx->replace_state =
-                                       IEEE80211_CHANCTX_WILL_BE_REPLACED;
-
-                       list_add_rcu(&new_ctx->list, &local->chanctx_list);
-               }
+               else
+                       new_ctx = ieee80211_replace_chanctx(local, chanreq,
+                                                           mode, curr_ctx);
+               if (IS_ERR(new_ctx))
+                       return PTR_ERR(new_ctx);
        }
 
        list_add(&link->reserved_chanctx_list, &new_ctx->reserved_links);