2  * llc_pdu.c - access to PDU internals
19 static u8 llc_pdu_get_pf_bit(struct llc_pdu_sn *pdu);
31  *	This function sets poll/final bit in LLC header (based on type of PDU).
38 	struct llc_pdu_sn *pdu;  in llc_pdu_set_pf_bit()  local
41 	pdu = llc_pdu_sn_hdr(skb);  in llc_pdu_set_pf_bit()
46 		pdu->ctrl_2 = (pdu->ctrl_2 & 0xFE) | bit_value;  in llc_pdu_set_pf_bit()
49 		pdu->ctrl_1 |= (pdu->ctrl_1 & 0xEF) | (bit_value << 4);  in llc_pdu_set_pf_bit()
60  *	PDU). In I or S pdus, p/f bit is right bit of fourth byte in header. In
66 	struct llc_pdu_sn *pdu;  in llc_pdu_decode_pf_bit()  local
69 	pdu = llc_pdu_sn_hdr(skb);  in llc_pdu_decode_pf_bit()
74 		*pf_bit = pdu->ctrl_2 & LLC_S_PF_BIT_MASK;  in llc_pdu_decode_pf_bit()
77 		*pf_bit = (pdu->ctrl_1 & LLC_U_PF_BIT_MASK) >> 4;  in llc_pdu_decode_pf_bit()
83  *	llc_pdu_init_as_disc_cmd - Builds DISC PDU
85  *	@p_bit: The P bit to set in the PDU
87  *	Builds a pdu frame as a DISC command.
91 	struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);  in llc_pdu_init_as_disc_cmd()  local
93 	pdu->ctrl_1  = LLC_PDU_TYPE_U;  in llc_pdu_init_as_disc_cmd()
94 	pdu->ctrl_1 |= LLC_2_PDU_CMD_DISC;  in llc_pdu_init_as_disc_cmd()
95 	pdu->ctrl_1 |= ((p_bit & 1) << 4) & LLC_U_PF_BIT_MASK;  in llc_pdu_init_as_disc_cmd()
99  *	llc_pdu_init_as_i_cmd - builds I pdu
101  *	@p_bit: The P bit to set in the PDU
102  *	@ns: The sequence number of the data PDU
103  *	@nr: The seq. number of the expected I PDU from the remote
105  *	Builds a pdu frame as an I command.
109 	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);  in llc_pdu_init_as_i_cmd()  local
111 	pdu->ctrl_1  = LLC_PDU_TYPE_I;  in llc_pdu_init_as_i_cmd()
112 	pdu->ctrl_2  = 0;  in llc_pdu_init_as_i_cmd()
113 	pdu->ctrl_2 |= (p_bit & LLC_I_PF_BIT_MASK); /* p/f bit */  in llc_pdu_init_as_i_cmd()
114 	pdu->ctrl_1 |= (ns << 1) & 0xFE;   /* set N(S) in bits 2..8 */  in llc_pdu_init_as_i_cmd()
115 	pdu->ctrl_2 |= (nr << 1) & 0xFE;   /* set N(R) in bits 10..16 */  in llc_pdu_init_as_i_cmd()
119  *	llc_pdu_init_as_rej_cmd - builds REJ PDU
121  *	@p_bit: The P bit to set in the PDU
122  *	@nr: The seq. number of the expected I PDU from the remote
124  *	Builds a pdu frame as a REJ command.
128 	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);  in llc_pdu_init_as_rej_cmd()  local
130 	pdu->ctrl_1  = LLC_PDU_TYPE_S;  in llc_pdu_init_as_rej_cmd()
131 	pdu->ctrl_1 |= LLC_2_PDU_CMD_REJ;  in llc_pdu_init_as_rej_cmd()
132 	pdu->ctrl_2  = 0;  in llc_pdu_init_as_rej_cmd()
133 	pdu->ctrl_2 |= p_bit & LLC_S_PF_BIT_MASK;  in llc_pdu_init_as_rej_cmd()
134 	pdu->ctrl_1 &= 0x0F;    /* setting bits 5..8 to zero(reserved) */  in llc_pdu_init_as_rej_cmd()
135 	pdu->ctrl_2 |= (nr << 1) & 0xFE; /* set N(R) in bits 10..16 */  in llc_pdu_init_as_rej_cmd()
139  *	llc_pdu_init_as_rnr_cmd - builds RNR pdu
141  *	@p_bit: The P bit to set in the PDU
142  *	@nr: The seq. number of the expected I PDU from the remote
144  *	Builds a pdu frame as an RNR command.
148 	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);  in llc_pdu_init_as_rnr_cmd()  local
150 	pdu->ctrl_1  = LLC_PDU_TYPE_S;  in llc_pdu_init_as_rnr_cmd()
151 	pdu->ctrl_1 |= LLC_2_PDU_CMD_RNR;  in llc_pdu_init_as_rnr_cmd()
152 	pdu->ctrl_2  = 0;  in llc_pdu_init_as_rnr_cmd()
153 	pdu->ctrl_2 |= p_bit & LLC_S_PF_BIT_MASK;  in llc_pdu_init_as_rnr_cmd()
154 	pdu->ctrl_1 &= 0x0F;    /* setting bits 5..8 to zero(reserved) */  in llc_pdu_init_as_rnr_cmd()
155 	pdu->ctrl_2 |= (nr << 1) & 0xFE; /* set N(R) in bits 10..16 */  in llc_pdu_init_as_rnr_cmd()
159  *	llc_pdu_init_as_rr_cmd - Builds RR pdu
161  *	@p_bit: The P bit to set in the PDU
162  *	@nr: The seq. number of the expected I PDU from the remote
164  *	Builds a pdu frame as an RR command.
168 	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);  in llc_pdu_init_as_rr_cmd()  local
170 	pdu->ctrl_1  = LLC_PDU_TYPE_S;  in llc_pdu_init_as_rr_cmd()
171 	pdu->ctrl_1 |= LLC_2_PDU_CMD_RR;  in llc_pdu_init_as_rr_cmd()
172 	pdu->ctrl_2  = p_bit & LLC_S_PF_BIT_MASK;  in llc_pdu_init_as_rr_cmd()
173 	pdu->ctrl_1 &= 0x0F;    /* setting bits 5..8 to zero(reserved) */  in llc_pdu_init_as_rr_cmd()
174 	pdu->ctrl_2 |= (nr << 1) & 0xFE; /* set N(R) in bits 10..16 */  in llc_pdu_init_as_rr_cmd()
178  *	llc_pdu_init_as_sabme_cmd - builds SABME pdu
180  *	@p_bit: The P bit to set in the PDU
182  *	Builds a pdu frame as an SABME command.
186 	struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);  in llc_pdu_init_as_sabme_cmd()  local
188 	pdu->ctrl_1  = LLC_PDU_TYPE_U;  in llc_pdu_init_as_sabme_cmd()
189 	pdu->ctrl_1 |= LLC_2_PDU_CMD_SABME;  in llc_pdu_init_as_sabme_cmd()
190 	pdu->ctrl_1 |= ((p_bit & 1) << 4) & LLC_U_PF_BIT_MASK;  in llc_pdu_init_as_sabme_cmd()
194  *	llc_pdu_init_as_dm_rsp - builds DM response pdu
196  *	@f_bit: The F bit to set in the PDU
198  *	Builds a pdu frame as a DM response.
202 	struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);  in llc_pdu_init_as_dm_rsp()  local
204 	pdu->ctrl_1  = LLC_PDU_TYPE_U;  in llc_pdu_init_as_dm_rsp()
205 	pdu->ctrl_1 |= LLC_2_PDU_RSP_DM;  in llc_pdu_init_as_dm_rsp()
206 	pdu->ctrl_1 |= ((f_bit & 1) << 4) & LLC_U_PF_BIT_MASK;  in llc_pdu_init_as_dm_rsp()
210  *	llc_pdu_init_as_frmr_rsp - builds FRMR response PDU
212  *	@prev_pdu: The rejected PDU frame
213  *	@f_bit: The F bit to set in the PDU
218  *	Builds a pdu frame as a FRMR response.
226 	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);  in llc_pdu_init_as_frmr_rsp()  local
228 	pdu->ctrl_1  = LLC_PDU_TYPE_U;  in llc_pdu_init_as_frmr_rsp()
229 	pdu->ctrl_1 |= LLC_2_PDU_RSP_FRMR;  in llc_pdu_init_as_frmr_rsp()
230 	pdu->ctrl_1 |= ((f_bit & 1) << 4) & LLC_U_PF_BIT_MASK;  in llc_pdu_init_as_frmr_rsp()
232 	frmr_info = (struct llc_frmr_info *)&pdu->ctrl_2;  in llc_pdu_init_as_frmr_rsp()
248  *	llc_pdu_init_as_rr_rsp - builds RR response pdu
250  *	@f_bit: The F bit to set in the PDU
251  *	@nr: The seq. number of the expected data PDU from the remote
253  *	Builds a pdu frame as an RR response.
257 	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);  in llc_pdu_init_as_rr_rsp()  local
259 	pdu->ctrl_1  = LLC_PDU_TYPE_S;  in llc_pdu_init_as_rr_rsp()
260 	pdu->ctrl_1 |= LLC_2_PDU_RSP_RR;  in llc_pdu_init_as_rr_rsp()
261 	pdu->ctrl_2  = 0;  in llc_pdu_init_as_rr_rsp()
262 	pdu->ctrl_2 |= f_bit & LLC_S_PF_BIT_MASK;  in llc_pdu_init_as_rr_rsp()
263 	pdu->ctrl_1 &= 0x0F;    /* setting bits 5..8 to zero(reserved) */  in llc_pdu_init_as_rr_rsp()
264 	pdu->ctrl_2 |= (nr << 1) & 0xFE;  /* set N(R) in bits 10..16 */  in llc_pdu_init_as_rr_rsp()
268  *	llc_pdu_init_as_rej_rsp - builds REJ response pdu
270  *	@f_bit: The F bit to set in the PDU
271  *	@nr: The seq. number of the expected data PDU from the remote
273  *	Builds a pdu frame as a REJ response.
277 	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);  in llc_pdu_init_as_rej_rsp()  local
279 	pdu->ctrl_1  = LLC_PDU_TYPE_S;  in llc_pdu_init_as_rej_rsp()
280 	pdu->ctrl_1 |= LLC_2_PDU_RSP_REJ;  in llc_pdu_init_as_rej_rsp()
281 	pdu->ctrl_2  = 0;  in llc_pdu_init_as_rej_rsp()
282 	pdu->ctrl_2 |= f_bit & LLC_S_PF_BIT_MASK;  in llc_pdu_init_as_rej_rsp()
283 	pdu->ctrl_1 &= 0x0F;    /* setting bits 5..8 to zero(reserved) */  in llc_pdu_init_as_rej_rsp()
284 	pdu->ctrl_2 |= (nr << 1) & 0xFE;  /* set N(R) in bits 10..16 */  in llc_pdu_init_as_rej_rsp()
288  *	llc_pdu_init_as_rnr_rsp - builds RNR response pdu
290  *	@f_bit: The F bit to set in the PDU
291  *	@nr: The seq. number of the expected data PDU from the remote
293  *	Builds a pdu frame as an RNR response.
297 	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);  in llc_pdu_init_as_rnr_rsp()  local
299 	pdu->ctrl_1  = LLC_PDU_TYPE_S;  in llc_pdu_init_as_rnr_rsp()
300 	pdu->ctrl_1 |= LLC_2_PDU_RSP_RNR;  in llc_pdu_init_as_rnr_rsp()
301 	pdu->ctrl_2  = 0;  in llc_pdu_init_as_rnr_rsp()
302 	pdu->ctrl_2 |= f_bit & LLC_S_PF_BIT_MASK;  in llc_pdu_init_as_rnr_rsp()
303 	pdu->ctrl_1 &= 0x0F;    /* setting bits 5..8 to zero(reserved) */  in llc_pdu_init_as_rnr_rsp()
304 	pdu->ctrl_2 |= (nr << 1) & 0xFE;  /* set N(R) in bits 10..16 */  in llc_pdu_init_as_rnr_rsp()
308  *	llc_pdu_init_as_ua_rsp - builds UA response pdu
310  *	@f_bit: The F bit to set in the PDU
312  *	Builds a pdu frame as a UA response.
316 	struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);  in llc_pdu_init_as_ua_rsp()  local
318 	pdu->ctrl_1  = LLC_PDU_TYPE_U;  in llc_pdu_init_as_ua_rsp()
319 	pdu->ctrl_1 |= LLC_2_PDU_RSP_UA;  in llc_pdu_init_as_ua_rsp()
320 	pdu->ctrl_1 |= ((f_bit & 1) << 4) & LLC_U_PF_BIT_MASK;  in llc_pdu_init_as_ua_rsp()
324  *	llc_pdu_decode_pdu_type - designates PDU type
326  *	@type: type of PDU (output argument).
328  *	This function designates type of PDU (I, S or U).
332 	struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);  in llc_pdu_decode_pdu_type()  local
334 	if (pdu->ctrl_1 & 1) {  in llc_pdu_decode_pdu_type()
335 		if ((pdu->ctrl_1 & LLC_PDU_TYPE_U) == LLC_PDU_TYPE_U)  in llc_pdu_decode_pdu_type()
344  *	llc_pdu_get_pf_bit - extracts p/f bit of input PDU
345  *	@pdu: pointer to LLC header.
347  *	This function extracts p/f bit of input PDU. at first examines type of
348  *	PDU and then extracts p/f bit. Returns the p/f bit.
350 static u8 llc_pdu_get_pf_bit(struct llc_pdu_sn *pdu)  in llc_pdu_get_pf_bit()  argument
355 	if (pdu->ctrl_1 & 1) {  in llc_pdu_get_pf_bit()
356 		if ((pdu->ctrl_1 & LLC_PDU_TYPE_U) == LLC_PDU_TYPE_U)  in llc_pdu_get_pf_bit()
365 		pf_bit = pdu->ctrl_2 & LLC_S_PF_BIT_MASK;  in llc_pdu_get_pf_bit()
368 		pf_bit = (pdu->ctrl_1 & LLC_U_PF_BIT_MASK) >> 4;  in llc_pdu_get_pf_bit()