From: Johannes Berg <johannes.berg@xxxxxxxxx>
For uAPSD support we'll need to have per-AC PS
buffers. As this is a major undertaking, split
the buffers before really adding support for
uAPSD. This already makes some reference to the
uapsd_queues variable, but for now that will
never be non-zero.
Since book-keeping is complicated, also change
the logic for keeping a maximum of frames only
and allow 64 frames per AC (up from 128 for a
station).
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
---
include/net/mac80211.h | 1
net/mac80211/debugfs_sta.c | 10 +-
net/mac80211/sta_info.c | 197 ++++++++++++++++++++++++++++++++++-----------
net/mac80211/sta_info.h | 24 ++---
net/mac80211/status.c | 17 +++
net/mac80211/tx.c | 42 +++++----
6 files changed, 211 insertions(+), 80 deletions(-)
--- a/net/mac80211/sta_info.c 2011-09-22 14:39:19.000000000 +0200
+++ b/net/mac80211/sta_info.c 2011-09-22 15:47:13.000000000 +0200
@@ -309,8 +309,10 @@ struct sta_info *sta_info_alloc(struct i
*/
sta->timer_to_tid[i] = i;
}
- skb_queue_head_init(&sta->ps_tx_buf);
- skb_queue_head_init(&sta->tx_filtered);
+ for (i = 0; i < IEEE80211_NUM_ACS; i++) {
+ skb_queue_head_init(&sta->ps_tx_buf[i]);
+ skb_queue_head_init(&sta->tx_filtered[i]);
+ }
for (i = 0; i < NUM_RX_DATA_QUEUES; i++)
sta->last_seq_ctrl[i] = cpu_to_le16(USHRT_MAX);
@@ -641,31 +643,73 @@ static inline void __bss_tim_clear(struc
bss->tim[aid / 8] &= ~(1 << (aid % 8));
}
+static unsigned long ieee80211_tids_for_ac(int ac)
+{
+ /* If we ever support TIDs > 7, this obviously needs to be adjusted */
+ switch (ac) {
+ case IEEE80211_AC_VO:
+ return BIT(6) | BIT(7);
+ case IEEE80211_AC_VI:
+ return BIT(4) | BIT(5);
+ case IEEE80211_AC_BE:
+ return BIT(0) | BIT(3);
+ case IEEE80211_AC_BK:
+ return BIT(1) | BIT(2);
+ default:
+ WARN_ON(1);
+ return 0;
+ }
+}
+
void sta_info_recalc_tim(struct sta_info *sta)
{
struct ieee80211_local *local = sta->local;
struct ieee80211_if_ap *bss = sta->sdata->bss;
unsigned long flags;
- bool have_data;
+ bool indicate_tim = false;
+ u8 ignore_for_tim = sta->sta.uapsd_queues;
+ int ac;
/* No need to do anything if the driver does all */
if (local->hw.flags & IEEE80211_HW_AP_LINK_PS)
return;
- have_data = test_sta_flags(sta, WLAN_STA_PS_DRIVER_BUF) ||
- !skb_queue_empty(&sta->tx_filtered) ||
- !skb_queue_empty(&sta->ps_tx_buf);
+ /*
+ * If all ACs are delivery-enabled then we should build
+ * the TIM bit for all ACs anyway; if only some are then
+ * we ignore those and build the TIM bit using only the
+ * non-enabled ones.
+ */
+ if (ignore_for_tim == BIT(IEEE80211_NUM_ACS) - 1)
+ ignore_for_tim = 0;
+
+ for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
+ unsigned long tids;
+
+ if (ignore_for_tim & BIT(ac))
+ continue;
+
+ indicate_tim |= !skb_queue_empty(&sta->tx_filtered[ac]) ||
+ !skb_queue_empty(&sta->ps_tx_buf[ac]);
+ if (indicate_tim)
+ break;
+
+ tids = ieee80211_tids_for_ac(ac);
+
+ indicate_tim |=
+ sta->driver_buffered_tids & tids;
+ }
spin_lock_irqsave(&local->sta_lock, flags);
- if (have_data)
+ if (indicate_tim)
__bss_tim_set(bss, sta->sta.aid);
else
__bss_tim_clear(bss, sta->sta.aid);
if (local->ops->set_tim) {
local->tim_in_locked_section = true;
- drv_set_tim(local, &sta->sta, have_data);
+ drv_set_tim(local, &sta->sta, indicate_tim);
local->tim_in_locked_section = false;
}
@@ -692,8 +736,8 @@ static bool sta_info_buffer_expired(stru
}
-static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
- struct sta_info *sta)
+static bool sta_info_cleanup_expire_buffered_ac(struct ieee80211_local *local,
+ struct sta_info *sta, int ac)
{
unsigned long flags;
struct sk_buff *skb;
@@ -706,13 +750,13 @@ static bool sta_info_cleanup_expire_buff
* total_ps_buffered counter.
*/
for (;;) {
- spin_lock_irqsave(&sta->tx_filtered.lock, flags);
- skb = skb_peek(&sta->tx_filtered);
+ spin_lock_irqsave(&sta->tx_filtered[ac].lock, flags);
+ skb = skb_peek(&sta->tx_filtered[ac]);
if (sta_info_buffer_expired(sta, skb))
- skb = __skb_dequeue(&sta->tx_filtered);
+ skb = __skb_dequeue(&sta->tx_filtered[ac]);
else
skb = NULL;
- spin_unlock_irqrestore(&sta->tx_filtered.lock, flags);
+ spin_unlock_irqrestore(&sta->tx_filtered[ac].lock, flags);
/*
* Frames are queued in order, so if this one
@@ -732,13 +776,13 @@ static bool sta_info_cleanup_expire_buff
* buffered frames.
*/
for (;;) {
- spin_lock_irqsave(&sta->ps_tx_buf.lock, flags);
- skb = skb_peek(&sta->ps_tx_buf);
+ spin_lock_irqsave(&sta->ps_tx_buf[ac].lock, flags);
+ skb = skb_peek(&sta->ps_tx_buf[ac]);
if (sta_info_buffer_expired(sta, skb))
- skb = __skb_dequeue(&sta->ps_tx_buf);
+ skb = __skb_dequeue(&sta->ps_tx_buf[ac]);
else
skb = NULL;
- spin_unlock_irqrestore(&sta->ps_tx_buf.lock, flags);
+ spin_unlock_irqrestore(&sta->ps_tx_buf[ac].lock, flags);
/*
* frames are queued in order, so if this one
@@ -768,8 +812,22 @@ static bool sta_info_cleanup_expire_buff
* used to check whether the cleanup timer still needs to run,
* if there are no frames we don't need to rearm the timer.
*/
- return !(skb_queue_empty(&sta->ps_tx_buf) &&
- skb_queue_empty(&sta->tx_filtered));
+ return !(skb_queue_empty(&sta->ps_tx_buf[ac]) &&
+ skb_queue_empty(&sta->tx_filtered[ac]));
+}
+
+static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
+ struct sta_info *sta)
+{
+ bool have_buffered = false;
+ int ac;
+
+ for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
+ have_buffered |=
+ sta_info_cleanup_expire_buffered_ac(local, sta, ac);
+ }
+
+ return have_buffered;
}
static int __must_check __sta_info_destroy(struct sta_info *sta)
@@ -777,7 +835,7 @@ static int __must_check __sta_info_destr
struct ieee80211_local *local;
struct ieee80211_sub_if_data *sdata;
unsigned long flags;
- int ret, i;
+ int ret, i, ac;
might_sleep();
@@ -814,9 +872,11 @@ static int __must_check __sta_info_destr
sta->dead = true;
- local->total_ps_buffered -= skb_queue_len(&sta->ps_tx_buf);
- __skb_queue_purge(&sta->ps_tx_buf);
- __skb_queue_purge(&sta->tx_filtered);
+ for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
+ local->total_ps_buffered -= skb_queue_len(&sta->ps_tx_buf[ac]);
+ __skb_queue_purge(&sta->ps_tx_buf[ac]);
+ __skb_queue_purge(&sta->tx_filtered[ac]);
+ }
if (test_and_clear_sta_flags(sta,
WLAN_STA_PS_STA | WLAN_STA_PS_DRIVER)) {
@@ -1044,17 +1104,33 @@ void ieee80211_sta_ps_deliver_wakeup(str
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sdata->local;
- int sent, buffered;
+ struct sk_buff_head pending;
+ int filtered = 0, buffered = 0, ac;
+
+ BUILD_BUG_ON(BITS_TO_LONGS(STA_TID_NUM) > 1);
+ sta->driver_buffered_tids = 0;
- clear_sta_flags(sta, WLAN_STA_PS_DRIVER_BUF);
if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta);
+ skb_queue_head_init(&pending);
+
/* Send all buffered frames to the station */
- sent = ieee80211_add_pending_skbs(local, &sta->tx_filtered);
- buffered = ieee80211_add_pending_skbs_fn(local, &sta->ps_tx_buf,
- clear_sta_ps_flags, sta);
- sent += buffered;
+ for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
+ int count = skb_queue_len(&pending), tmp;
+
+ skb_queue_splice_tail_init(&sta->tx_filtered[ac], &pending);
+ tmp = skb_queue_len(&pending);
+ filtered += tmp - count;
+ count = tmp;
+
+ skb_queue_splice_tail_init(&sta->ps_tx_buf[ac], &pending);
+ tmp = skb_queue_len(&pending);
+ buffered += tmp - count;
+ }
+
+ ieee80211_add_pending_skbs_fn(local, &pending, clear_sta_ps_flags, sta);
+
local->total_ps_buffered -= buffered;
sta_info_recalc_tim(sta);
@@ -1062,7 +1138,7 @@ void ieee80211_sta_ps_deliver_wakeup(str
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames "
"since STA not sleeping anymore\n", sdata->name,
- sta->sta.addr, sta->sta.aid, sent - buffered, buffered);
+ sta->sta.addr, sta->sta.aid, filtered, buffered);
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
}
@@ -1070,17 +1146,43 @@ void ieee80211_sta_ps_deliver_poll_respo
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sdata->local;
- struct sk_buff *skb;
- int no_pending_pkts;
+ struct sk_buff *skb = NULL;
+ bool more_data = false;
+ int ac;
+ u8 ignore_for_response = sta->sta.uapsd_queues;
+
+ /*
+ * If all ACs are delivery-enabled then we should reply
+ * from any of them, if only some are enabled we reply
+ * only from the non-enabled ones.
+ */
+ if (ignore_for_response == BIT(IEEE80211_NUM_ACS) - 1)
+ ignore_for_response = 0;
+
+ /*
+ * Get response frame and more data bit for it.
+ */
+ for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
+ if (ignore_for_response & BIT(ac))
+ continue;
+
+ if (!skb) {
+ skb = skb_dequeue(&sta->tx_filtered[ac]);
+ if (!skb) {
+ skb = skb_dequeue(&sta->ps_tx_buf[ac]);
+ if (skb)
+ local->total_ps_buffered--;
+ }
+ }
+
+ /* FIXME: take into account driver-buffered frames */
- skb = skb_dequeue(&sta->tx_filtered);
- if (!skb) {
- skb = skb_dequeue(&sta->ps_tx_buf);
- if (skb)
- local->total_ps_buffered--;
+ if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
+ !skb_queue_empty(&sta->ps_tx_buf[ac])) {
+ more_data = true;
+ break;
+ }
}
- no_pending_pkts = skb_queue_empty(&sta->tx_filtered) &&
- skb_queue_empty(&sta->ps_tx_buf);
if (skb) {
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
@@ -1094,14 +1196,13 @@ void ieee80211_sta_ps_deliver_poll_respo
info->flags |= IEEE80211_TX_CTL_PSPOLL_RESPONSE;
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
- printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
- sta->sta.addr, sta->sta.aid,
- skb_queue_len(&sta->ps_tx_buf));
+ printk(KERN_DEBUG "STA %pM aid %d: PS Poll\n",
+ sta->sta.addr, sta->sta.aid);
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
/* Use MoreData flag to indicate whether there are more
* buffered frames for this STA */
- if (no_pending_pkts)
+ if (!more_data)
hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
else
hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
@@ -1143,10 +1244,14 @@ void ieee80211_sta_set_buffered(struct i
{
struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
- if (!buffered)
+ if (WARN_ON(tid >= STA_TID_NUM))
return;
- set_sta_flags(sta, WLAN_STA_PS_DRIVER_BUF);
+ if (buffered)
+ set_bit(tid, &sta->driver_buffered_tids);
+ else
+ clear_bit(tid, &sta->driver_buffered_tids);
+
sta_info_recalc_tim(sta);
}
EXPORT_SYMBOL(ieee80211_sta_set_buffered);
--- a/net/mac80211/sta_info.h 2011-09-22 14:39:19.000000000 +0200
+++ b/net/mac80211/sta_info.h 2011-09-22 15:47:33.000000000 +0200
@@ -43,8 +43,6 @@
* be in the queues
* @WLAN_STA_PSPOLL: Station sent PS-poll while driver was keeping
* station in power-save mode, reply when the driver unblocks.
- * @WLAN_STA_PS_DRIVER_BUF: Station has frames pending in driver internal
- * buffers. Automatically cleared on station wake-up.
*/
enum ieee80211_sta_info_flags {
WLAN_STA_AUTH = 1<<0,
@@ -60,7 +58,6 @@ enum ieee80211_sta_info_flags {
WLAN_STA_BLOCK_BA = 1<<11,
WLAN_STA_PS_DRIVER = 1<<12,
WLAN_STA_PSPOLL = 1<<13,
- WLAN_STA_PS_DRIVER_BUF = 1<<14,
};
#define STA_TID_NUM 16
@@ -207,11 +204,13 @@ struct sta_ampdu_mlme {
* @drv_unblock_wk: used for driver PS unblocking
* @listen_interval: listen interval of this station, when we're acting as AP
* @flags: STA flags, see &enum ieee80211_sta_info_flags
- * @ps_tx_buf: buffer of frames to transmit to this station
- * when it leaves power saving state
- * @tx_filtered: buffer of frames we already tried to transmit
- * but were filtered by hardware due to STA having entered
- * power saving state
+ * @ps_tx_buf: buffers (per AC) of frames to transmit to this station
+ * when it leaves power saving state or polls
+ * @tx_filtered: buffers (per AC) of frames we already tried to
+ * transmit but were filtered by hardware due to STA having
+ * entered power saving state, these are also delivered to
+ * the station when it leaves powersave or polls for frames
+ * @driver_buffered_tids: bitmap of TIDs the driver has data buffered on
* @rx_packets: Number of MSDUs received from this STA
* @rx_bytes: Number of bytes received from this STA
* @wep_weak_iv_count: number of weak WEP IVs received from this station
@@ -281,8 +280,9 @@ struct sta_info {
* STA powersave frame queues, no more than the internal
* locking required.
*/
- struct sk_buff_head ps_tx_buf;
- struct sk_buff_head tx_filtered;
+ struct sk_buff_head ps_tx_buf[IEEE80211_NUM_ACS];
+ struct sk_buff_head tx_filtered[IEEE80211_NUM_ACS];
+ unsigned long driver_buffered_tids;
/* Updated from RX path only, no locking requirements */
unsigned long rx_packets, rx_bytes;
@@ -429,8 +429,8 @@ rcu_dereference_protected_tid_tx(struct
#define STA_HASH(sta) (sta[5])
-/* Maximum number of frames to buffer per power saving station */
-#define STA_MAX_TX_BUFFER 128
+/* Maximum number of frames to buffer per power saving station per AC */
+#define STA_MAX_TX_BUFFER 64
/* Minimum buffered frame expiry time. If STA uses listen interval that is
* smaller than this value, the minimum value here is used instead. */
--- a/include/net/mac80211.h 2011-09-22 14:39:19.000000000 +0200
+++ b/include/net/mac80211.h 2011-09-22 15:47:13.000000000 +0200
@@ -109,6 +109,7 @@ enum ieee80211_ac_numbers {
IEEE80211_AC_BE = 2,
IEEE80211_AC_BK = 3,
};
+#define IEEE80211_NUM_ACS 4
/**
* struct ieee80211_tx_queue_params - transmit queue configuration
--- a/net/mac80211/status.c 2011-09-22 14:39:19.000000000 +0200
+++ b/net/mac80211/status.c 2011-09-22 15:47:13.000000000 +0200
@@ -14,6 +14,7 @@
#include "rate.h"
#include "mesh.h"
#include "led.h"
+#include "wme.h"
void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
@@ -43,6 +44,8 @@ static void ieee80211_handle_filtered_fr
struct sk_buff *skb)
{
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+ struct ieee80211_hdr *hdr = (void *)skb->data;
+ int ac;
/*
* This skb 'survived' a round-trip through the driver, and
@@ -62,6 +65,14 @@ static void ieee80211_handle_filtered_fr
sta->tx_filtered_count++;
+ if (ieee80211_is_data_qos(hdr->frame_control)) {
+ int tid = *ieee80211_get_qos_ctl(hdr) &
+ IEEE80211_QOS_CTL_TID_MASK;
+ ac = ieee802_1d_to_ac[tid & 7];
+ } else {
+ ac = IEEE80211_AC_BE;
+ }
+
/*
* Clear the TX filter mask for this STA when sending the next
* packet. If the STA went to power save mode, this will happen
@@ -104,8 +115,8 @@ static void ieee80211_handle_filtered_fr
* unknown.
*/
if (test_sta_flags(sta, WLAN_STA_PS_STA) &&
- skb_queue_len(&sta->tx_filtered) < STA_MAX_TX_BUFFER) {
- skb_queue_tail(&sta->tx_filtered, skb);
+ skb_queue_len(&sta->tx_filtered[ac]) < STA_MAX_TX_BUFFER) {
+ skb_queue_tail(&sta->tx_filtered[ac], skb);
sta_info_recalc_tim(sta);
if (!timer_pending(&local->sta_cleanup))
@@ -127,7 +138,7 @@ static void ieee80211_handle_filtered_fr
if (net_ratelimit())
wiphy_debug(local->hw.wiphy,
"dropped TX filtered frame, queue_len=%d PS=%d @%lu\n",
- skb_queue_len(&sta->tx_filtered),
+ skb_queue_len(&sta->tx_filtered[ac]),
!!test_sta_flags(sta, WLAN_STA_PS_STA), jiffies);
#endif
dev_kfree_skb(skb);
--- a/net/mac80211/debugfs_sta.c 2011-09-22 14:38:53.000000000 +0200
+++ b/net/mac80211/debugfs_sta.c 2011-09-22 15:47:10.000000000 +0200
@@ -78,8 +78,14 @@ static ssize_t sta_num_ps_buf_frames_rea
size_t count, loff_t *ppos)
{
struct sta_info *sta = file->private_data;
- return mac80211_format_buffer(userbuf, count, ppos, "%u\n",
- skb_queue_len(&sta->ps_tx_buf));
+ char buf[17*IEEE80211_NUM_ACS], *p = buf;
+ int ac;
+
+ for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
+ p += scnprintf(p, sizeof(buf)+buf-p, "AC%d: %d\n", ac,
+ skb_queue_len(&sta->ps_tx_buf[ac]) +
+ skb_queue_len(&sta->tx_filtered[ac]));
+ return simple_read_from_buffer(userbuf, count, ppos, buf, p - buf);
}
STA_OPS(num_ps_buf_frames);
--- a/net/mac80211/tx.c 2011-09-22 14:39:19.000000000 +0200
+++ b/net/mac80211/tx.c 2011-09-22 15:47:12.000000000 +0200
@@ -343,13 +343,22 @@ static void purge_old_ps_buffers(struct
total += skb_queue_len(&ap->ps_bc_buf);
}
+ /*
+ * Drop one frame from each station from the lowest-priority
+ * AC that has frames at all.
+ */
list_for_each_entry_rcu(sta, &local->sta_list, list) {
- skb = skb_dequeue(&sta->ps_tx_buf);
- if (skb) {
- purged++;
- dev_kfree_skb(skb);
+ int ac;
+
+ for (ac = IEEE80211_AC_BK; ac >= IEEE80211_AC_VO; ac--) {
+ skb = skb_dequeue(&sta->ps_tx_buf[ac]);
+ total += skb_queue_len(&sta->ps_tx_buf[ac]);
+ if (skb) {
+ purged++;
+ dev_kfree_skb(skb);
+ break;
+ }
}
- total += skb_queue_len(&sta->ps_tx_buf);
}
rcu_read_unlock();
@@ -448,22 +457,21 @@ ieee80211_tx_h_unicast_ps_buf(struct iee
if (unlikely((staflags & (WLAN_STA_PS_STA | WLAN_STA_PS_DRIVER)) &&
!(info->flags & IEEE80211_TX_CTL_PSPOLL_RESPONSE))) {
+ int ac = skb_get_queue_mapping(tx->skb);
+
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
- printk(KERN_DEBUG "STA %pM aid %d: PS buffer (entries "
- "before %d)\n",
- sta->sta.addr, sta->sta.aid,
- skb_queue_len(&sta->ps_tx_buf));
+ printk(KERN_DEBUG "STA %pM aid %d: PS buffer for AC %d\n",
+ sta->sta.addr, sta->sta.aid, ac);
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
purge_old_ps_buffers(tx->local);
- if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) {
- struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf);
+ if (skb_queue_len(&sta->ps_tx_buf[ac]) >= STA_MAX_TX_BUFFER) {
+ struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf[ac]);
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
- if (net_ratelimit()) {
- printk(KERN_DEBUG "%s: STA %pM TX "
- "buffer full - dropping oldest frame\n",
- tx->sdata->name, sta->sta.addr);
- }
+ if (net_ratelimit())
+ printk(KERN_DEBUG "%s: STA %pM TX buffer for "
+ "AC %d full - dropping oldest frame\n",
+ tx->sdata->name, sta->sta.addr, ac);
#endif
dev_kfree_skb(old);
} else
@@ -472,7 +480,7 @@ ieee80211_tx_h_unicast_ps_buf(struct iee
info->control.jiffies = jiffies;
info->control.vif = &tx->sdata->vif;
info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
- skb_queue_tail(&sta->ps_tx_buf, tx->skb);
+ skb_queue_tail(&sta->ps_tx_buf[ac], tx->skb);
if (!timer_pending(&local->sta_cleanup))
mod_timer(&local->sta_cleanup,
--
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