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staging: rtl8723bs: Use % 4096 instead of & 0xfff

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The sequence number is constrained to a range of [0, 4095], which
is a total of 4096 values. The bitmask operation using `& 0xfff` is
used to perform this wrap-around. While this is functionally correct,
it obscures the intended semantic of a 4096-based wrap.

Using a modulo operation `% 4096u` makes the wrap-around logic
explicit and easier to understand. It clearly signals that the
sequence number cycles through a range of 4096 values.
It also makes the code robust against potential changes of the 4096
upper limit, especially when it becomes a non power-of-2 value while
the AND(&) works solely for power-of-2 values.

The use of `% 4096u` also guarantees that the modulo operation is
performed with unsigned arithmetic, preventing potential issues with
the signed types.

Found by Coccinelle.

Suggested-by: Andy Shevchenko <andy@kernel.org>
Suggested-by: David Laight <david.laight.linux@gmail.com>
Signed-off-by: Abraham Samuel Adekunle <abrahamadekunle50@gmail.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://lore.kernel.org/r/e8d515539ba560961003eae15d301d03e6cdd17d.1744966511.git.abrahamadekunle50@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Abraham Samuel Adekunle
2025-04-18 09:47:55 +00:00
committed by Greg Kroah-Hartman
parent 28925280ed
commit a5df13cd7b
3 changed files with 7 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/staging/rtl8723bs/core/rtw_mlme_ext.c
View File

@@ -3511,7 +3511,7 @@ void issue_action_BA(struct adapter *padapter, unsigned char *raddr, unsigned ch
/* if ((psta = rtw_get_stainfo(pstapriv, pmlmeinfo->network.mac_address)) != NULL) */
psta = rtw_get_stainfo(pstapriv, raddr);
if (psta) {
start_seq = (psta->sta_xmitpriv.txseq_tid[status & 0x07]&0xfff) + 1;
start_seq = (psta->sta_xmitpriv.txseq_tid[status & 0x07] % 4096u) + 1;
psta->BA_starting_seqctrl[status & 0x07] = start_seq;

6
drivers/staging/rtl8723bs/core/rtw_recv.c
View File

@@ -1641,7 +1641,7 @@ static int check_indicate_seq(struct recv_reorder_ctrl *preorder_ctrl, u16 seq_n
struct dvobj_priv *psdpriv = padapter->dvobj;
struct debug_priv *pdbgpriv = &psdpriv->drv_dbg;
u8 wsize = preorder_ctrl->wsize_b;
u16 wend = (preorder_ctrl->indicate_seq + wsize - 1) & 0xFFF;/* 4096; */
u16 wend = (preorder_ctrl->indicate_seq + wsize - 1) % 4096u;
/* Rx Reorder initialize condition. */
if (preorder_ctrl->indicate_seq == 0xFFFF)
@@ -1657,7 +1657,7 @@ static int check_indicate_seq(struct recv_reorder_ctrl *preorder_ctrl, u16 seq_n
/* 2. Incoming SeqNum is larger than the WinEnd => Window shift N */
/* */
if (SN_EQUAL(seq_num, preorder_ctrl->indicate_seq)) {
preorder_ctrl->indicate_seq = (preorder_ctrl->indicate_seq + 1) & 0xFFF;
preorder_ctrl->indicate_seq = (preorder_ctrl->indicate_seq + 1) % 4096u;
} else if (SN_LESS(wend, seq_num)) {
/* boundary situation, when seq_num cross 0xFFF */
@@ -1772,7 +1772,7 @@ static int recv_indicatepkts_in_order(struct adapter *padapter, struct recv_reor
list_del_init(&(prframe->u.hdr.list));
if (SN_EQUAL(preorder_ctrl->indicate_seq, pattrib->seq_num))
preorder_ctrl->indicate_seq = (preorder_ctrl->indicate_seq + 1) & 0xFFF;
preorder_ctrl->indicate_seq = (preorder_ctrl->indicate_seq + 1) % 4096u;
/* Set this as a lock to make sure that only one thread is indicating packet. */
/* pTS->RxIndicateState = RXTS_INDICATE_PROCESSING; */

6
drivers/staging/rtl8723bs/core/rtw_xmit.c
View File

@@ -943,7 +943,7 @@ s32 rtw_make_wlanhdr(struct adapter *padapter, u8 *hdr, struct pkt_attrib *pattr
if (psta) {
psta->sta_xmitpriv.txseq_tid[pattrib->priority]++;
psta->sta_xmitpriv.txseq_tid[pattrib->priority] &= 0xFFF;
psta->sta_xmitpriv.txseq_tid[pattrib->priority] %= 4096u;
pattrib->seqnum = psta->sta_xmitpriv.txseq_tid[pattrib->priority];
SetSeqNum(hdr, pattrib->seqnum);
@@ -964,12 +964,12 @@ s32 rtw_make_wlanhdr(struct adapter *padapter, u8 *hdr, struct pkt_attrib *pattr
pattrib->ampdu_en = false;/* AGG BK */
} else if (SN_EQUAL(pattrib->seqnum, tx_seq)) {
psta->BA_starting_seqctrl[pattrib->priority & 0x0f] =
(tx_seq + 1) & 0xfff;
(tx_seq + 1) % 4096u;
pattrib->ampdu_en = true;/* AGG EN */
} else {
psta->BA_starting_seqctrl[pattrib->priority & 0x0f] =
(pattrib->seqnum + 1) & 0xfff;
(pattrib->seqnum + 1) % 4096u;
pattrib->ampdu_en = true;/* AGG EN */
}