2011-09-18 02:57:43

by Christian Lamparter

Subject: [PATCH] ath9k: use ACCESS_ONCE_RW for write assignments

This patch fixes a compiler error which was introduced by
"ath9k_hw: add a new API for setting tx descriptors" [2b63a4].

ar9002_mac.c:185:2: error: assignment of read-only location
...
ar9003_mac.c:37:2: error: assignment of read-only location
...

Signed-off-by: Christian Lamparter <[email protected]>
---
compile tested...
---
diff --git a/drivers/net/wireless/ath/ath9k/ar9002_mac.c b/drivers/net/wireless/ath/ath9k/ar9002_mac.c
index f7d8e51..0f00e49 100644
--- a/drivers/net/wireless/ath/ath9k/ar9002_mac.c
+++ b/drivers/net/wireless/ath/ath9k/ar9002_mac.c
@@ -182,8 +182,8 @@ ar9002_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
ads->ds_txstatus6 = ads->ds_txstatus7 = 0;
ads->ds_txstatus8 = ads->ds_txstatus9 = 0;

- ACCESS_ONCE(ads->ds_link) = i->link;
- ACCESS_ONCE(ads->ds_data) = i->buf_addr[0];
+ ACCESS_ONCE_RW(ads->ds_link) = i->link;
+ ACCESS_ONCE_RW(ads->ds_data) = i->buf_addr[0];

ctl1 = i->buf_len[0] | (i->is_last ? 0 : AR_TxMore);
ctl6 = SM(i->keytype, AR_EncrType);
@@ -197,26 +197,26 @@ ar9002_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)

if ((i->is_first || i->is_last) &&
i->aggr != AGGR_BUF_MIDDLE && i->aggr != AGGR_BUF_LAST) {
- ACCESS_ONCE(ads->ds_ctl2) = set11nTries(i->rates, 0)
+ ACCESS_ONCE_RW(ads->ds_ctl2) = set11nTries(i->rates, 0)
| set11nTries(i->rates, 1)
| set11nTries(i->rates, 2)
| set11nTries(i->rates, 3)
| (i->dur_update ? AR_DurUpdateEna : 0)
| SM(0, AR_BurstDur);

- ACCESS_ONCE(ads->ds_ctl3) = set11nRate(i->rates, 0)
+ ACCESS_ONCE_RW(ads->ds_ctl3) = set11nRate(i->rates, 0)
| set11nRate(i->rates, 1)
| set11nRate(i->rates, 2)
| set11nRate(i->rates, 3);
} else {
- ACCESS_ONCE(ads->ds_ctl2) = 0;
- ACCESS_ONCE(ads->ds_ctl3) = 0;
+ ACCESS_ONCE_RW(ads->ds_ctl2) = 0;
+ ACCESS_ONCE_RW(ads->ds_ctl3) = 0;
}

if (!i->is_first) {
- ACCESS_ONCE(ads->ds_ctl0) = 0;
- ACCESS_ONCE(ads->ds_ctl1) = ctl1;
- ACCESS_ONCE(ads->ds_ctl6) = ctl6;
+ ACCESS_ONCE_RW(ads->ds_ctl0) = 0;
+ ACCESS_ONCE_RW(ads->ds_ctl1) = ctl1;
+ ACCESS_ONCE_RW(ads->ds_ctl6) = ctl6;
return;
}

@@ -241,7 +241,7 @@ ar9002_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
break;
}

- ACCESS_ONCE(ads->ds_ctl0) = (i->pkt_len & AR_FrameLen)
+ ACCESS_ONCE_RW(ads->ds_ctl0) = (i->pkt_len & AR_FrameLen)
| (i->flags & ATH9K_TXDESC_VMF ? AR_VirtMoreFrag : 0)
| SM(i->txpower, AR_XmitPower)
| (i->flags & ATH9K_TXDESC_VEOL ? AR_VEOL : 0)
@@ -251,19 +251,19 @@ ar9002_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
| (i->flags & ATH9K_TXDESC_RTSENA ? AR_RTSEnable :
(i->flags & ATH9K_TXDESC_CTSENA ? AR_CTSEnable : 0));

- ACCESS_ONCE(ads->ds_ctl1) = ctl1;
- ACCESS_ONCE(ads->ds_ctl6) = ctl6;
+ ACCESS_ONCE_RW(ads->ds_ctl1) = ctl1;
+ ACCESS_ONCE_RW(ads->ds_ctl6) = ctl6;

if (i->aggr == AGGR_BUF_MIDDLE || i->aggr == AGGR_BUF_LAST)
return;

- ACCESS_ONCE(ads->ds_ctl4) = set11nPktDurRTSCTS(i->rates, 0)
+ ACCESS_ONCE_RW(ads->ds_ctl4) = set11nPktDurRTSCTS(i->rates, 0)
| set11nPktDurRTSCTS(i->rates, 1);

- ACCESS_ONCE(ads->ds_ctl5) = set11nPktDurRTSCTS(i->rates, 2)
+ ACCESS_ONCE_RW(ads->ds_ctl5) = set11nPktDurRTSCTS(i->rates, 2)
| set11nPktDurRTSCTS(i->rates, 3);

- ACCESS_ONCE(ads->ds_ctl7) = set11nRateFlags(i->rates, 0)
+ ACCESS_ONCE_RW(ads->ds_ctl7) = set11nRateFlags(i->rates, 0)
| set11nRateFlags(i->rates, 1)
| set11nRateFlags(i->rates, 2)
| set11nRateFlags(i->rates, 3)
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_mac.c b/drivers/net/wireless/ath/ath9k/ar9003_mac.c
index 6cabc85..38a13a4 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_mac.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_mac.c
@@ -34,47 +34,47 @@ ar9003_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
(i->qcu << AR_TxQcuNum_S) | 0x17;

checksum += val;
- ACCESS_ONCE(ads->info) = val;
+ ACCESS_ONCE_RW(ads->info) = val;

checksum += i->link;
- ACCESS_ONCE(ads->link) = i->link;
+ ACCESS_ONCE_RW(ads->link) = i->link;

checksum += i->buf_addr[0];
- ACCESS_ONCE(ads->data0) = i->buf_addr[0];
+ ACCESS_ONCE_RW(ads->data0) = i->buf_addr[0];
checksum += i->buf_addr[1];
- ACCESS_ONCE(ads->data1) = i->buf_addr[1];
+ ACCESS_ONCE_RW(ads->data1) = i->buf_addr[1];
checksum += i->buf_addr[2];
- ACCESS_ONCE(ads->data2) = i->buf_addr[2];
+ ACCESS_ONCE_RW(ads->data2) = i->buf_addr[2];
checksum += i->buf_addr[3];
- ACCESS_ONCE(ads->data3) = i->buf_addr[3];
+ ACCESS_ONCE_RW(ads->data3) = i->buf_addr[3];

checksum += (val = (i->buf_len[0] << AR_BufLen_S) & AR_BufLen);
- ACCESS_ONCE(ads->ctl3) = val;
+ ACCESS_ONCE_RW(ads->ctl3) = val;
checksum += (val = (i->buf_len[1] << AR_BufLen_S) & AR_BufLen);
- ACCESS_ONCE(ads->ctl5) = val;
+ ACCESS_ONCE_RW(ads->ctl5) = val;
checksum += (val = (i->buf_len[2] << AR_BufLen_S) & AR_BufLen);
- ACCESS_ONCE(ads->ctl7) = val;
+ ACCESS_ONCE_RW(ads->ctl7) = val;
checksum += (val = (i->buf_len[3] << AR_BufLen_S) & AR_BufLen);
- ACCESS_ONCE(ads->ctl9) = val;
+ ACCESS_ONCE_RW(ads->ctl9) = val;

checksum = (u16) (((checksum & 0xffff) + (checksum >> 16)) & 0xffff);
- ACCESS_ONCE(ads->ctl10) = checksum;
+ ACCESS_ONCE_RW(ads->ctl10) = checksum;

if (i->is_first || i->is_last) {
- ACCESS_ONCE(ads->ctl13) = set11nTries(i->rates, 0)
+ ACCESS_ONCE_RW(ads->ctl13) = set11nTries(i->rates, 0)
| set11nTries(i->rates, 1)
| set11nTries(i->rates, 2)
| set11nTries(i->rates, 3)
| (i->dur_update ? AR_DurUpdateEna : 0)
| SM(0, AR_BurstDur);

- ACCESS_ONCE(ads->ctl14) = set11nRate(i->rates, 0)
+ ACCESS_ONCE_RW(ads->ctl14) = set11nRate(i->rates, 0)
| set11nRate(i->rates, 1)
| set11nRate(i->rates, 2)
| set11nRate(i->rates, 3);
} else {
- ACCESS_ONCE(ads->ctl13) = 0;
- ACCESS_ONCE(ads->ctl14) = 0;
+ ACCESS_ONCE_RW(ads->ctl13) = 0;
+ ACCESS_ONCE_RW(ads->ctl14) = 0;
}

ads->ctl20 = 0;
@@ -83,17 +83,17 @@ ar9003_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)

ctl17 = SM(i->keytype, AR_EncrType);
if (!i->is_first) {
- ACCESS_ONCE(ads->ctl11) = 0;
- ACCESS_ONCE(ads->ctl12) = i->is_last ? 0 : AR_TxMore;
- ACCESS_ONCE(ads->ctl15) = 0;
- ACCESS_ONCE(ads->ctl16) = 0;
- ACCESS_ONCE(ads->ctl17) = ctl17;
- ACCESS_ONCE(ads->ctl18) = 0;
- ACCESS_ONCE(ads->ctl19) = 0;
+ ACCESS_ONCE_RW(ads->ctl11) = 0;
+ ACCESS_ONCE_RW(ads->ctl12) = i->is_last ? 0 : AR_TxMore;
+ ACCESS_ONCE_RW(ads->ctl15) = 0;
+ ACCESS_ONCE_RW(ads->ctl16) = 0;
+ ACCESS_ONCE_RW(ads->ctl17) = ctl17;
+ ACCESS_ONCE_RW(ads->ctl18) = 0;
+ ACCESS_ONCE_RW(ads->ctl19) = 0;
return;
}

- ACCESS_ONCE(ads->ctl11) = (i->pkt_len & AR_FrameLen)
+ ACCESS_ONCE_RW(ads->ctl11) = (i->pkt_len & AR_FrameLen)
| (i->flags & ATH9K_TXDESC_VMF ? AR_VirtMoreFrag : 0)
| SM(i->txpower, AR_XmitPower)
| (i->flags & ATH9K_TXDESC_VEOL ? AR_VEOL : 0)
@@ -129,22 +129,22 @@ ar9003_set_txdesc(struct ath_hw *ah, void *ds, struct ath_tx_info *i)
val = (i->flags & ATH9K_TXDESC_PAPRD) >> ATH9K_TXDESC_PAPRD_S;
ctl12 |= SM(val, AR_PAPRDChainMask);

- ACCESS_ONCE(ads->ctl12) = ctl12;
- ACCESS_ONCE(ads->ctl17) = ctl17;
+ ACCESS_ONCE_RW(ads->ctl12) = ctl12;
+ ACCESS_ONCE_RW(ads->ctl17) = ctl17;

- ACCESS_ONCE(ads->ctl15) = set11nPktDurRTSCTS(i->rates, 0)
+ ACCESS_ONCE_RW(ads->ctl15) = set11nPktDurRTSCTS(i->rates, 0)
| set11nPktDurRTSCTS(i->rates, 1);

- ACCESS_ONCE(ads->ctl16) = set11nPktDurRTSCTS(i->rates, 2)
+ ACCESS_ONCE_RW(ads->ctl16) = set11nPktDurRTSCTS(i->rates, 2)
| set11nPktDurRTSCTS(i->rates, 3);

- ACCESS_ONCE(ads->ctl18) = set11nRateFlags(i->rates, 0)
+ ACCESS_ONCE_RW(ads->ctl18) = set11nRateFlags(i->rates, 0)
| set11nRateFlags(i->rates, 1)
| set11nRateFlags(i->rates, 2)
| set11nRateFlags(i->rates, 3)
| SM(i->rtscts_rate, AR_RTSCTSRate);

- ACCESS_ONCE(ads->ctl19) = AR_Not_Sounding;
+ ACCESS_ONCE_RW(ads->ctl19) = AR_Not_Sounding;
}

static u16 ar9003_calc_ptr_chksum(struct ar9003_txc *ads)

2011-09-18 09:05:18

by Felix Fietkau

Subject: Re: [PATCH] ath9k: use ACCESS_ONCE_RW for write assignments

On 2011-09-18 4:57 AM, Christian Lamparter wrote:
> This patch fixes a compiler error which was introduced by
> "ath9k_hw: add a new API for setting tx descriptors" [2b63a4].
>
> ar9002_mac.c:185:2: error: assignment of read-only location
> ...
> ar9003_mac.c:37:2: error: assignment of read-only location
> ...
>
> Signed-off-by: Christian Lamparter<[email protected]>
When and where was ACCESS_ONCE_RW added? It's not in wireless-testing
and I can only find references to it on the web in grsecurity patches.

- Felix

2011-09-18 11:18:18

by Christian Lamparter

Subject: Re: [PATCH] ath9k: use ACCESS_ONCE_RW for write assignments

On Sunday 18 September 2011 11:05:06 Felix Fietkau wrote:
> On 2011-09-18 4:57 AM, Christian Lamparter wrote:
> > This patch fixes a compiler error which was introduced by
> > "ath9k_hw: add a new API for setting tx descriptors" [2b63a4].
> >
> > ar9002_mac.c:185:2: error: assignment of read-only location
> > ...
> > ar9003_mac.c:37:2: error: assignment of read-only location
> > ...
> >
> > Signed-off-by: Christian Lamparter<[email protected]>
> When and where was ACCESS_ONCE_RW added? It's not in wireless-testing
> and I can only find references to it on the web in grsecurity patches.
Sorry! You are right. ACCESS_ONCE_RW is part of grsecurity, looks
like I have to bother Brad with this one.

Regards,
Chr