1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (c) 2010 Cisco Systems, Inc.
5 * Portions based on tcm_loop_fabric_scsi.c and libfc/fc_fcp.c
7 * Copyright (c) 2007 Intel Corporation. All rights reserved.
8 * Copyright (c) 2008 Red Hat, Inc. All rights reserved.
9 * Copyright (c) 2008 Mike Christie
10 * Copyright (c) 2009 Rising Tide, Inc.
11 * Copyright (c) 2009 Linux-iSCSI.org
12 * Copyright (c) 2009 Nicholas A. Bellinger <nab@linux-iscsi.org>
15 /* XXX TBD some includes may be extraneous */
17 #include <linux/module.h>
18 #include <linux/moduleparam.h>
19 #include <linux/utsname.h>
20 #include <linux/init.h>
21 #include <linux/slab.h>
22 #include <linux/kthread.h>
23 #include <linux/types.h>
24 #include <linux/string.h>
25 #include <linux/configfs.h>
26 #include <linux/ctype.h>
27 #include <linux/hash.h>
28 #include <linux/ratelimit.h>
29 #include <asm/unaligned.h>
30 #include <scsi/libfc.h>
31 #include <scsi/fc_encode.h>
33 #include <target/target_core_base.h>
34 #include <target/target_core_fabric.h>
39 * Deliver read data back to initiator.
40 * XXX TBD handle resource problems later.
42 int ft_queue_data_in(struct se_cmd *se_cmd)
44 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
45 struct fc_frame *fp = NULL;
47 struct fc_lport *lport;
48 struct scatterlist *sg = NULL;
50 u32 f_ctl = FC_FC_EX_CTX | FC_FC_REL_OFF;
58 struct page *page = NULL;
68 if (se_cmd->scsi_status == SAM_STAT_TASK_SET_FULL)
71 ep = fc_seq_exch(cmd->seq);
73 cmd->seq = fc_seq_start_next(cmd->seq);
75 remaining = se_cmd->data_length;
78 * Setup to use first mem list entry, unless no data.
80 BUG_ON(remaining && !se_cmd->t_data_sg);
82 sg = se_cmd->t_data_sg;
88 /* no scatter/gather in skb for odd word length due to fc_seq_send() */
89 use_sg = !(remaining % 4);
92 struct fc_seq *seq = cmd->seq;
95 pr_debug("%s: Command aborted, xid 0x%x\n",
101 mem_len = min((size_t)sg->length, remaining);
102 mem_off = sg->offset;
107 * If lport's has capability of Large Send Offload LSO)
108 * , then allow 'frame_len' to be as big as 'lso_max'
109 * if indicated transfer length is >= lport->lso_max
111 frame_len = (lport->seq_offload) ? lport->lso_max :
112 cmd->sess->max_frame;
113 frame_len = min(frame_len, remaining);
114 fp = fc_frame_alloc(lport, use_sg ? 0 : frame_len);
117 to = fc_frame_payload_get(fp, 0);
119 frame_off += frame_len;
121 * Setup the frame's max payload which is used by base
122 * driver to indicate HW about max frame size, so that
123 * HW can do fragmentation appropriately based on
124 * "gso_max_size" of underline netdev.
126 fr_max_payload(fp) = cmd->sess->max_frame;
128 tlen = min(mem_len, frame_len);
131 off_in_page = mem_off;
134 skb_fill_page_desc(fp_skb(fp),
135 skb_shinfo(fp_skb(fp))->nr_frags,
136 page, off_in_page, tlen);
138 fp_skb(fp)->data_len += tlen;
139 fp_skb(fp)->truesize += page_size(page);
142 from = kmap_atomic(page + (mem_off >> PAGE_SHIFT));
144 from += offset_in_page(mem_off);
145 tlen = min(tlen, (size_t)(PAGE_SIZE -
146 offset_in_page(mem_off)));
147 memcpy(to, from, tlen);
148 kunmap_atomic(page_addr);
158 (skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN))
161 f_ctl |= FC_FC_END_SEQ;
162 fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
163 FC_TYPE_FCP, f_ctl, fh_off);
164 error = fc_seq_send(lport, seq, fp);
166 pr_info_ratelimited("%s: Failed to send frame %p, "
167 "xid <0x%x>, remaining %zu, "
169 __func__, fp, ep->xid,
170 remaining, lport->lso_max);
172 * Go ahead and set TASK_SET_FULL status ignoring the
173 * rest of the DataIN, and immediately attempt to
174 * send the response via ft_queue_status() in order
175 * to notify the initiator that it should reduce it's
176 * per LUN queue_depth.
178 se_cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
183 return ft_queue_status(se_cmd);
186 static void ft_execute_work(struct work_struct *work)
188 struct ft_cmd *cmd = container_of(work, struct ft_cmd, work);
190 target_execute_cmd(&cmd->se_cmd);
194 * Receive write data frame.
196 void ft_recv_write_data(struct ft_cmd *cmd, struct fc_frame *fp)
198 struct se_cmd *se_cmd = &cmd->se_cmd;
199 struct fc_seq *seq = cmd->seq;
201 struct fc_lport *lport;
202 struct fc_frame_header *fh;
203 struct scatterlist *sg = NULL;
209 struct page *page = NULL;
216 fh = fc_frame_header_get(fp);
217 if (!(ntoh24(fh->fh_f_ctl) & FC_FC_REL_OFF))
220 f_ctl = ntoh24(fh->fh_f_ctl);
221 ep = fc_seq_exch(seq);
223 if (cmd->was_ddp_setup) {
226 * Since DDP (Large Rx offload) was setup for this request,
227 * payload is expected to be copied directly to user buffers.
229 buf = fc_frame_payload_get(fp, 1);
231 pr_err("%s: xid 0x%x, f_ctl 0x%x, cmd->sg %p, "
232 "cmd->sg_cnt 0x%x. DDP was setup"
233 " hence not expected to receive frame with "
234 "payload, Frame will be dropped if"
235 "'Sequence Initiative' bit in f_ctl is"
236 "not set\n", __func__, ep->xid, f_ctl,
237 se_cmd->t_data_sg, se_cmd->t_data_nents);
239 * Invalidate HW DDP context if it was setup for respective
240 * command. Invalidation of HW DDP context is requited in both
241 * situation (success and error).
243 ft_invl_hw_context(cmd);
246 * If "Sequence Initiative (TSI)" bit set in f_ctl, means last
247 * write data frame is received successfully where payload is
248 * posted directly to user buffer and only the last frame's
249 * header is posted in receive queue.
251 * If "Sequence Initiative (TSI)" bit is not set, means error
252 * condition w.r.t. DDP, hence drop the packet and let explict
253 * ABORTS from other end of exchange timer trigger the recovery.
255 if (f_ctl & FC_FC_SEQ_INIT)
261 rel_off = ntohl(fh->fh_parm_offset);
262 frame_len = fr_len(fp);
263 if (frame_len <= sizeof(*fh))
265 frame_len -= sizeof(*fh);
266 from = fc_frame_payload_get(fp, 0);
267 if (rel_off >= se_cmd->data_length)
269 if (frame_len + rel_off > se_cmd->data_length)
270 frame_len = se_cmd->data_length - rel_off;
273 * Setup to use first mem list entry, unless no data.
275 BUG_ON(frame_len && !se_cmd->t_data_sg);
277 sg = se_cmd->t_data_sg;
278 mem_len = sg->length;
279 mem_off = sg->offset;
286 mem_len = sg->length;
287 mem_off = sg->offset;
290 if (rel_off >= mem_len) {
299 tlen = min(mem_len, frame_len);
301 to = kmap_atomic(page + (mem_off >> PAGE_SHIFT));
303 to += offset_in_page(mem_off);
304 tlen = min(tlen, (size_t)(PAGE_SIZE -
305 offset_in_page(mem_off)));
306 memcpy(to, from, tlen);
307 kunmap_atomic(page_addr);
313 cmd->write_data_len += tlen;
316 if (cmd->write_data_len == se_cmd->data_length) {
317 INIT_WORK(&cmd->work, ft_execute_work);
318 queue_work(cmd->sess->tport->tpg->workqueue, &cmd->work);
325 * Handle and cleanup any HW specific resources if
326 * received ABORTS, errors, timeouts.
328 void ft_invl_hw_context(struct ft_cmd *cmd)
331 struct fc_exch *ep = NULL;
332 struct fc_lport *lport = NULL;
337 /* Cleanup the DDP context in HW if DDP was setup */
338 if (cmd->was_ddp_setup && seq) {
339 ep = fc_seq_exch(seq);
342 if (lport && (ep->xid <= lport->lro_xid)) {
344 * "ddp_done" trigger invalidation of HW
345 * specific DDP context
347 cmd->write_data_len = lport->tt.ddp_done(lport,
351 * Resetting same variable to indicate HW's
352 * DDP context has been invalidated to avoid
353 * re_invalidation of same context (context is
354 * identified using ep->xid)
356 cmd->was_ddp_setup = 0;