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/utsname.h>
32 #include <linux/init.h>
33 #include <linux/slab.h>
34 #include <linux/kthread.h>
35 #include <linux/types.h>
36 #include <linux/string.h>
37 #include <linux/configfs.h>
38 #include <linux/ctype.h>
39 #include <linux/hash.h>
40 #include <linux/ratelimit.h>
41 #include <asm/unaligned.h>
42 #include <scsi/scsi.h>
43 #include <scsi/scsi_host.h>
44 #include <scsi/scsi_device.h>
45 #include <scsi/scsi_cmnd.h>
46 #include <scsi/libfc.h>
47 #include <scsi/fc_encode.h>
49 #include <target/target_core_base.h>
50 #include <target/target_core_fabric.h>
51 #include <target/target_core_configfs.h>
52 #include <target/configfs_macros.h>
57 * Deliver read data back to initiator.
58 * XXX TBD handle resource problems later.
60 int ft_queue_data_in(struct se_cmd
*se_cmd
)
62 struct ft_cmd
*cmd
= container_of(se_cmd
, struct ft_cmd
, se_cmd
);
63 struct fc_frame
*fp
= NULL
;
65 struct fc_lport
*lport
;
66 struct scatterlist
*sg
= NULL
;
68 u32 f_ctl
= FC_FC_EX_CTX
| FC_FC_REL_OFF
;
76 struct page
*page
= NULL
;
85 ep
= fc_seq_exch(cmd
->seq
);
87 cmd
->seq
= lport
->tt
.seq_start_next(cmd
->seq
);
89 remaining
= se_cmd
->data_length
;
92 * Setup to use first mem list entry, unless no data.
94 BUG_ON(remaining
&& !se_cmd
->t_data_sg
);
96 sg
= se_cmd
->t_data_sg
;
102 /* no scatter/gather in skb for odd word length due to fc_seq_send() */
103 use_sg
= !(remaining
% 4);
108 mem_len
= min((size_t)sg
->length
, remaining
);
109 mem_off
= sg
->offset
;
114 * If lport's has capability of Large Send Offload LSO)
115 * , then allow 'frame_len' to be as big as 'lso_max'
116 * if indicated transfer length is >= lport->lso_max
118 frame_len
= (lport
->seq_offload
) ? lport
->lso_max
:
119 cmd
->sess
->max_frame
;
120 frame_len
= min(frame_len
, remaining
);
121 fp
= fc_frame_alloc(lport
, use_sg
? 0 : frame_len
);
124 to
= fc_frame_payload_get(fp
, 0);
126 frame_off
+= frame_len
;
128 * Setup the frame's max payload which is used by base
129 * driver to indicate HW about max frame size, so that
130 * HW can do fragmentation appropriately based on
131 * "gso_max_size" of underline netdev.
133 fr_max_payload(fp
) = cmd
->sess
->max_frame
;
135 tlen
= min(mem_len
, frame_len
);
138 off_in_page
= mem_off
;
141 skb_fill_page_desc(fp_skb(fp
),
142 skb_shinfo(fp_skb(fp
))->nr_frags
,
143 page
, off_in_page
, tlen
);
145 fp_skb(fp
)->data_len
+= tlen
;
146 fp_skb(fp
)->truesize
+=
147 PAGE_SIZE
<< compound_order(page
);
150 from
= kmap_atomic(page
+ (mem_off
>> PAGE_SHIFT
));
152 from
+= mem_off
& ~PAGE_MASK
;
153 tlen
= min(tlen
, (size_t)(PAGE_SIZE
-
154 (mem_off
& ~PAGE_MASK
)));
155 memcpy(to
, from
, tlen
);
156 kunmap_atomic(page_addr
);
166 (skb_shinfo(fp_skb(fp
))->nr_frags
< FC_FRAME_SG_LEN
))
169 f_ctl
|= FC_FC_END_SEQ
;
170 fc_fill_fc_hdr(fp
, FC_RCTL_DD_SOL_DATA
, ep
->did
, ep
->sid
,
171 FC_TYPE_FCP
, f_ctl
, fh_off
);
172 error
= lport
->tt
.seq_send(lport
, cmd
->seq
, fp
);
174 /* XXX For now, initiator will retry */
175 pr_err_ratelimited("%s: Failed to send frame %p, "
176 "xid <0x%x>, remaining %zu, "
178 __func__
, fp
, ep
->xid
,
179 remaining
, lport
->lso_max
);
182 return ft_queue_status(se_cmd
);
185 static void ft_execute_work(struct work_struct
*work
)
187 struct ft_cmd
*cmd
= container_of(work
, struct ft_cmd
, work
);
189 target_execute_cmd(&cmd
->se_cmd
);
193 * Receive write data frame.
195 void ft_recv_write_data(struct ft_cmd
*cmd
, struct fc_frame
*fp
)
197 struct se_cmd
*se_cmd
= &cmd
->se_cmd
;
198 struct fc_seq
*seq
= cmd
->seq
;
200 struct fc_lport
*lport
;
201 struct fc_frame_header
*fh
;
202 struct scatterlist
*sg
= NULL
;
208 struct page
*page
= NULL
;
215 fh
= fc_frame_header_get(fp
);
216 if (!(ntoh24(fh
->fh_f_ctl
) & FC_FC_REL_OFF
))
219 f_ctl
= ntoh24(fh
->fh_f_ctl
);
220 ep
= fc_seq_exch(seq
);
222 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
+= mem_off
& ~PAGE_MASK
;
304 tlen
= min(tlen
, (size_t)(PAGE_SIZE
-
305 (mem_off
& ~PAGE_MASK
)));
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;