2 * Copyright (c) 2010 Cisco Systems, Inc.
4 * Portions based on tcm_loop_fabric_scsi.c and libfc/fc_fcp.c
6 * Copyright (c) 2007 Intel Corporation. All rights reserved.
7 * Copyright (c) 2008 Red Hat, Inc. All rights reserved.
8 * Copyright (c) 2008 Mike Christie
9 * Copyright (c) 2009 Rising Tide, Inc.
10 * Copyright (c) 2009 Linux-iSCSI.org
11 * Copyright (c) 2009 Nicholas A. Bellinger <nab@linux-iscsi.org>
13 * This program is free software; you can redistribute it and/or modify it
14 * under the terms and conditions of the GNU General Public License,
15 * version 2, as published by the Free Software Foundation.
17 * This program is distributed in the hope it will be useful, but WITHOUT
18 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
19 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
22 * You should have received a copy of the GNU General Public License along with
23 * this program; if not, write to the Free Software Foundation, Inc.,
24 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
27 /* XXX TBD some includes may be extraneous */
29 #include <linux/module.h>
30 #include <linux/moduleparam.h>
31 #include <linux/version.h>
32 #include <generated/utsrelease.h>
33 #include <linux/utsname.h>
34 #include <linux/init.h>
35 #include <linux/slab.h>
36 #include <linux/kthread.h>
37 #include <linux/types.h>
38 #include <linux/string.h>
39 #include <linux/configfs.h>
40 #include <linux/ctype.h>
41 #include <linux/hash.h>
42 #include <linux/ratelimit.h>
43 #include <asm/unaligned.h>
44 #include <scsi/scsi.h>
45 #include <scsi/scsi_host.h>
46 #include <scsi/scsi_device.h>
47 #include <scsi/scsi_cmnd.h>
48 #include <scsi/libfc.h>
49 #include <scsi/fc_encode.h>
51 #include <target/target_core_base.h>
52 #include <target/target_core_transport.h>
53 #include <target/target_core_fabric_ops.h>
54 #include <target/target_core_device.h>
55 #include <target/target_core_tpg.h>
56 #include <target/target_core_configfs.h>
57 #include <target/configfs_macros.h>
62 * Deliver read data back to initiator.
63 * XXX TBD handle resource problems later.
65 int ft_queue_data_in(struct se_cmd *se_cmd)
67 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
68 struct fc_frame *fp = NULL;
70 struct fc_lport *lport;
71 struct scatterlist *sg = NULL;
73 u32 f_ctl = FC_FC_EX_CTX | FC_FC_REL_OFF;
81 struct page *page = NULL;
88 ep = fc_seq_exch(cmd->seq);
90 cmd->seq = lport->tt.seq_start_next(cmd->seq);
92 remaining = se_cmd->data_length;
95 * Setup to use first mem list entry, unless no data.
97 BUG_ON(remaining && !se_cmd->t_data_sg);
99 sg = se_cmd->t_data_sg;
100 mem_len = sg->length;
101 mem_off = sg->offset;
105 /* no scatter/gather in skb for odd word length due to fc_seq_send() */
106 use_sg = !(remaining % 4);
111 mem_len = min((size_t)sg->length, remaining);
112 mem_off = sg->offset;
117 * If lport's has capability of Large Send Offload LSO)
118 * , then allow 'frame_len' to be as big as 'lso_max'
119 * if indicated transfer length is >= lport->lso_max
121 frame_len = (lport->seq_offload) ? lport->lso_max :
122 cmd->sess->max_frame;
123 frame_len = min(frame_len, remaining);
124 fp = fc_frame_alloc(lport, use_sg ? 0 : frame_len);
127 to = fc_frame_payload_get(fp, 0);
129 frame_off += frame_len;
131 * Setup the frame's max payload which is used by base
132 * driver to indicate HW about max frame size, so that
133 * HW can do fragmentation appropriately based on
134 * "gso_max_size" of underline netdev.
136 fr_max_payload(fp) = cmd->sess->max_frame;
138 tlen = min(mem_len, frame_len);
141 off_in_page = mem_off;
144 skb_fill_page_desc(fp_skb(fp),
145 skb_shinfo(fp_skb(fp))->nr_frags,
146 page, off_in_page, tlen);
148 fp_skb(fp)->data_len += tlen;
149 fp_skb(fp)->truesize +=
150 PAGE_SIZE << compound_order(page);
153 from = kmap_atomic(page + (mem_off >> PAGE_SHIFT),
156 from += mem_off & ~PAGE_MASK;
157 tlen = min(tlen, (size_t)(PAGE_SIZE -
158 (mem_off & ~PAGE_MASK)));
159 memcpy(to, from, tlen);
160 kunmap_atomic(page_addr, KM_SOFTIRQ0);
170 (skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN))
173 f_ctl |= FC_FC_END_SEQ;
174 fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
175 FC_TYPE_FCP, f_ctl, fh_off);
176 error = lport->tt.seq_send(lport, cmd->seq, fp);
178 /* XXX For now, initiator will retry */
179 pr_err_ratelimited("%s: Failed to send frame %p, "
180 "xid <0x%x>, remaining %zu, "
182 __func__, fp, ep->xid,
183 remaining, lport->lso_max);
186 return ft_queue_status(se_cmd);
190 * Receive write data frame.
192 void ft_recv_write_data(struct ft_cmd *cmd, struct fc_frame *fp)
194 struct se_cmd *se_cmd = &cmd->se_cmd;
195 struct fc_seq *seq = cmd->seq;
197 struct fc_lport *lport;
198 struct fc_frame_header *fh;
199 struct scatterlist *sg = NULL;
205 struct page *page = NULL;
212 fh = fc_frame_header_get(fp);
213 if (!(ntoh24(fh->fh_f_ctl) & FC_FC_REL_OFF))
217 * Doesn't expect even single byte of payload. Payload
218 * is expected to be copied directly to user buffers
219 * due to DDP (Large Rx offload) feature, hence
220 * BUG_ON if BUF is non-NULL
222 buf = fc_frame_payload_get(fp, 1);
223 if (cmd->was_ddp_setup && buf) {
224 pr_debug("%s: When DDP was setup, not expected to"
225 "receive frame with payload, Payload shall be"
226 "copied directly to buffer instead of coming "
227 "via. legacy receive queues\n", __func__);
232 * If ft_cmd indicated 'ddp_setup', in that case only the last frame
233 * should come with 'TSI bit being set'. If 'TSI bit is not set and if
234 * data frame appears here, means error condition. In both the cases
235 * release the DDP context (ddp_put) and in error case, as well
236 * initiate error recovery mechanism.
238 ep = fc_seq_exch(seq);
239 if (cmd->was_ddp_setup) {
244 if (cmd->was_ddp_setup && ep->xid != FC_XID_UNKNOWN) {
245 f_ctl = ntoh24(fh->fh_f_ctl);
247 * If TSI bit set in f_ctl, means last write data frame is
248 * received successfully where payload is posted directly
249 * to user buffer and only the last frame's header is posted
250 * in legacy receive queue
252 if (f_ctl & FC_FC_SEQ_INIT) { /* TSI bit set in FC frame */
253 cmd->write_data_len = lport->tt.ddp_done(lport,
258 * Updating the write_data_len may be meaningless at
259 * this point, but just in case if required in future
260 * for debugging or any other purpose
262 pr_err("%s: Received frame with TSI bit not"
263 " being SET, dropping the frame, "
264 "cmd->sg <%p>, cmd->sg_cnt <0x%x>\n",
265 __func__, cmd->sg, cmd->sg_cnt);
266 cmd->write_data_len = lport->tt.ddp_done(lport,
268 lport->tt.seq_exch_abort(cmd->seq, 0);
273 rel_off = ntohl(fh->fh_parm_offset);
274 frame_len = fr_len(fp);
275 if (frame_len <= sizeof(*fh))
277 frame_len -= sizeof(*fh);
278 from = fc_frame_payload_get(fp, 0);
279 if (rel_off >= se_cmd->data_length)
281 if (frame_len + rel_off > se_cmd->data_length)
282 frame_len = se_cmd->data_length - rel_off;
285 * Setup to use first mem list entry, unless no data.
287 BUG_ON(frame_len && !se_cmd->t_data_sg);
289 sg = se_cmd->t_data_sg;
290 mem_len = sg->length;
291 mem_off = sg->offset;
298 mem_len = sg->length;
299 mem_off = sg->offset;
302 if (rel_off >= mem_len) {
311 tlen = min(mem_len, frame_len);
313 to = kmap_atomic(page + (mem_off >> PAGE_SHIFT),
316 to += mem_off & ~PAGE_MASK;
317 tlen = min(tlen, (size_t)(PAGE_SIZE -
318 (mem_off & ~PAGE_MASK)));
319 memcpy(to, from, tlen);
320 kunmap_atomic(page_addr, KM_SOFTIRQ0);
326 cmd->write_data_len += tlen;
329 if (cmd->write_data_len == se_cmd->data_length)
330 transport_generic_handle_data(se_cmd);