2024-06-05 18:46:19

by Felix Fietkau

[permalink] [raw]
Subject: [RFC v2 6/7] wifi: mac80211: move code in ieee80211_link_reserve_chanctx to a helper

Reduces indentation in preparation for further changes

Signed-off-by: Felix Fietkau <[email protected]>
---
net/mac80211/chan.c | 141 ++++++++++++++++++++++-----------------------
1 file changed, 72 insertions(+), 69 deletions(-)

diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index 0e899c07bc2b..ac49c2c71d2b 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -1060,6 +1060,71 @@ 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,
@@ -1067,7 +1132,7 @@ 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);

@@ -1077,76 +1142,14 @@ 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);
--
git-series 0.9.1