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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 Signed-off-by: Abraham Samuel Adekunle --- Coccinelle semantic patch used to find cases: @@ expression e; @@ * e & 0xfff To ensure this change does not affect the functional behaviour, I compared the generated object files before and after the change using the `cmp` which compares the two object files byte by byte as shown below: $ make drivers/staging/rtl8723bs/core/rtw_xmit.o $ cmp rtw_xmit_before.o rtw_xmit_after.o No differences were found in the output, confirming that the change does not alter the compiled output. drivers/staging/rtl8723bs/core/rtw_mlme_ext.c | 2 +- drivers/staging/rtl8723bs/core/rtw_recv.c | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/staging/rtl8723bs/core/rtw_mlme_ext.c b/drivers/staging/rtl8723bs/core/rtw_mlme_ext.c index 952ce6dd5af9..f712ea0cabee 100644 --- a/drivers/staging/rtl8723bs/core/rtw_mlme_ext.c +++ b/drivers/staging/rtl8723bs/core/rtw_mlme_ext.c @@ -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; diff --git a/drivers/staging/rtl8723bs/core/rtw_recv.c b/drivers/staging/rtl8723bs/core/rtw_recv.c index a389ba5ecc6f..25411cc5c738 100644 --- a/drivers/staging/rtl8723bs/core/rtw_recv.c +++ b/drivers/staging/rtl8723bs/core/rtw_recv.c @@ -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; */ -- 2.34.1