mac80211: compute chanctx refcount on-the-fly
It doesn't make much sense to store refcount in
the chanctx structure. One still needs to hold
chanctx_mtx to get the value safely. Besides,
refcount isn't on performance critical paths.
This will make implementing chanctx reservation
refcounting a little easier.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index e4166b3..d8b1b86 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -9,6 +9,41 @@
#include "ieee80211_i.h"
#include "driver-ops.h"
+static int ieee80211_chanctx_num_assigned(struct ieee80211_local *local,
+ struct ieee80211_chanctx *ctx)
+{
+ struct ieee80211_sub_if_data *sdata;
+ int num = 0;
+
+ lockdep_assert_held(&local->chanctx_mtx);
+
+ list_for_each_entry(sdata, &ctx->assigned_vifs, assigned_chanctx_list)
+ num++;
+
+ return num;
+}
+
+static int ieee80211_chanctx_num_reserved(struct ieee80211_local *local,
+ struct ieee80211_chanctx *ctx)
+{
+ struct ieee80211_sub_if_data *sdata;
+ int num = 0;
+
+ lockdep_assert_held(&local->chanctx_mtx);
+
+ list_for_each_entry(sdata, &ctx->reserved_vifs, reserved_chanctx_list)
+ num++;
+
+ return num;
+}
+
+int ieee80211_chanctx_refcount(struct ieee80211_local *local,
+ struct ieee80211_chanctx *ctx)
+{
+ return ieee80211_chanctx_num_assigned(local, ctx) +
+ ieee80211_chanctx_num_reserved(local, ctx);
+}
+
static int ieee80211_num_chanctx(struct ieee80211_local *local)
{
struct ieee80211_chanctx *ctx;
@@ -463,7 +498,7 @@
{
lockdep_assert_held(&local->chanctx_mtx);
- WARN_ON_ONCE(ctx->refcount != 0);
+ WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
list_del_rcu(&ctx->list);
ieee80211_del_chanctx(local, ctx);
@@ -542,7 +577,6 @@
if (conf) {
curr_ctx = container_of(conf, struct ieee80211_chanctx, conf);
- curr_ctx->refcount--;
drv_unassign_vif_chanctx(local, sdata, curr_ctx);
conf = NULL;
list_del(&sdata->assigned_chanctx_list);
@@ -553,7 +587,6 @@
if (ret)
goto out;
- new_ctx->refcount++;
conf = &new_ctx->conf;
list_add(&sdata->assigned_chanctx_list,
&new_ctx->assigned_vifs);
@@ -564,14 +597,14 @@
sdata->vif.bss_conf.idle = !conf;
- if (curr_ctx && curr_ctx->refcount > 0) {
+ if (curr_ctx && ieee80211_chanctx_num_assigned(local, curr_ctx) > 0) {
ieee80211_recalc_chanctx_chantype(local, curr_ctx);
ieee80211_recalc_smps_chanctx(local, curr_ctx);
ieee80211_recalc_radar_chanctx(local, curr_ctx);
ieee80211_recalc_chanctx_min_def(local, curr_ctx);
}
- if (new_ctx && new_ctx->refcount > 0) {
+ if (new_ctx && ieee80211_chanctx_num_assigned(local, new_ctx) > 0) {
ieee80211_recalc_txpower(sdata);
ieee80211_recalc_chanctx_min_def(local, new_ctx);
}
@@ -603,7 +636,7 @@
ieee80211_vif_unreserve_chanctx(sdata);
ieee80211_assign_vif_chanctx(sdata, NULL);
- if (ctx->refcount == 0)
+ if (ieee80211_chanctx_refcount(local, ctx) == 0)
ieee80211_free_chanctx(local, ctx);
}
@@ -735,7 +768,7 @@
ret = ieee80211_assign_vif_chanctx(sdata, ctx);
if (ret) {
/* if assign fails refcount stays the same */
- if (ctx->refcount == 0)
+ if (ieee80211_chanctx_refcount(local, ctx) == 0)
ieee80211_free_chanctx(local, ctx);
goto out;
}
@@ -759,7 +792,7 @@
IEEE80211_CHAN_DISABLED))
return -EINVAL;
- if (ctx->refcount != 1)
+ if (ieee80211_chanctx_refcount(local, ctx) != 1)
return -EINVAL;
if (sdata->vif.bss_conf.chandef.width != chandef->width) {
@@ -865,7 +898,7 @@
list_del(&sdata->reserved_chanctx_list);
sdata->reserved_chanctx = NULL;
- if (--ctx->refcount == 0)
+ if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0)
ieee80211_free_chanctx(sdata->local, ctx);
return 0;
@@ -894,7 +927,7 @@
new_ctx = ieee80211_find_reservation_chanctx(local, chandef, mode);
if (!new_ctx) {
- if (curr_ctx->refcount == 1 &&
+ if (ieee80211_chanctx_refcount(local, curr_ctx) == 1 &&
(local->hw.flags & IEEE80211_HW_CHANGE_RUNNING_CHANCTX)) {
/* if we're the only users of the chanctx and
* the driver supports changing a running
@@ -915,7 +948,6 @@
}
list_add(&sdata->reserved_chanctx_list, &new_ctx->reserved_vifs);
- new_ctx->refcount++;
sdata->reserved_chanctx = new_ctx;
sdata->reserved_chandef = *chandef;
sdata->reserved_radar_required = radar_required;
@@ -961,7 +993,6 @@
sdata->vif.bss_conf.chandef = sdata->reserved_chandef;
/* unref our reservation */
- ctx->refcount--;
sdata->reserved_chanctx = NULL;
sdata->radar_required = sdata->reserved_radar_required;
list_del(&sdata->reserved_chanctx_list);
@@ -974,11 +1005,11 @@
goto out;
} else {
ret = ieee80211_assign_vif_chanctx(sdata, ctx);
- if (old_ctx->refcount == 0)
+ if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
ieee80211_free_chanctx(local, old_ctx);
if (ret) {
/* if assign fails refcount stays the same */
- if (ctx->refcount == 0)
+ if (ieee80211_chanctx_refcount(local, ctx) == 0)
ieee80211_free_chanctx(local, ctx);
goto out;
}