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git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - drivers/target/tcm_fc/tfc_io.c
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/libfc.h>
43 #include <scsi/fc_encode.h>
45 #include <target/target_core_base.h>
46 #include <target/target_core_fabric.h>
47 #include <target/configfs_macros.h>
52 * Deliver read data back to initiator.
53 * XXX TBD handle resource problems later.
55 int ft_queue_data_in(struct se_cmd
*se_cmd
)
57 struct ft_cmd
*cmd
= container_of(se_cmd
, struct ft_cmd
, se_cmd
);
58 struct fc_frame
*fp
= NULL
;
60 struct fc_lport
*lport
;
61 struct scatterlist
*sg
= NULL
;
63 u32 f_ctl
= FC_FC_EX_CTX
| FC_FC_REL_OFF
;
71 struct page
*page
= NULL
;
81 if (se_cmd
->scsi_status
== SAM_STAT_TASK_SET_FULL
)
84 ep
= fc_seq_exch(cmd
->seq
);
86 cmd
->seq
= lport
->tt
.seq_start_next(cmd
->seq
);
88 remaining
= se_cmd
->data_length
;
91 * Setup to use first mem list entry, unless no data.
93 BUG_ON(remaining
&& !se_cmd
->t_data_sg
);
95 sg
= se_cmd
->t_data_sg
;
101 /* no scatter/gather in skb for odd word length due to fc_seq_send() */
102 use_sg
= !(remaining
% 4);
105 struct fc_seq
*seq
= cmd
->seq
;
108 pr_debug("%s: Command aborted, xid 0x%x\n",
114 mem_len
= min((size_t)sg
->length
, remaining
);
115 mem_off
= sg
->offset
;
120 * If lport's has capability of Large Send Offload LSO)
121 * , then allow 'frame_len' to be as big as 'lso_max'
122 * if indicated transfer length is >= lport->lso_max
124 frame_len
= (lport
->seq_offload
) ? lport
->lso_max
:
125 cmd
->sess
->max_frame
;
126 frame_len
= min(frame_len
, remaining
);
127 fp
= fc_frame_alloc(lport
, use_sg
? 0 : frame_len
);
130 to
= fc_frame_payload_get(fp
, 0);
132 frame_off
+= frame_len
;
134 * Setup the frame's max payload which is used by base
135 * driver to indicate HW about max frame size, so that
136 * HW can do fragmentation appropriately based on
137 * "gso_max_size" of underline netdev.
139 fr_max_payload(fp
) = cmd
->sess
->max_frame
;
141 tlen
= min(mem_len
, frame_len
);
144 off_in_page
= mem_off
;
147 skb_fill_page_desc(fp_skb(fp
),
148 skb_shinfo(fp_skb(fp
))->nr_frags
,
149 page
, off_in_page
, tlen
);
151 fp_skb(fp
)->data_len
+= tlen
;
152 fp_skb(fp
)->truesize
+=
153 PAGE_SIZE
<< compound_order(page
);
156 from
= kmap_atomic(page
+ (mem_off
>> PAGE_SHIFT
));
158 from
+= mem_off
& ~PAGE_MASK
;
159 tlen
= min(tlen
, (size_t)(PAGE_SIZE
-
160 (mem_off
& ~PAGE_MASK
)));
161 memcpy(to
, from
, tlen
);
162 kunmap_atomic(page_addr
);
172 (skb_shinfo(fp_skb(fp
))->nr_frags
< FC_FRAME_SG_LEN
))
175 f_ctl
|= FC_FC_END_SEQ
;
176 fc_fill_fc_hdr(fp
, FC_RCTL_DD_SOL_DATA
, ep
->did
, ep
->sid
,
177 FC_TYPE_FCP
, f_ctl
, fh_off
);
178 error
= lport
->tt
.seq_send(lport
, seq
, fp
);
180 pr_info_ratelimited("%s: Failed to send frame %p, "
181 "xid <0x%x>, remaining %zu, "
183 __func__
, fp
, ep
->xid
,
184 remaining
, lport
->lso_max
);
186 * Go ahead and set TASK_SET_FULL status ignoring the
187 * rest of the DataIN, and immediately attempt to
188 * send the response via ft_queue_status() in order
189 * to notify the initiator that it should reduce it's
190 * per LUN queue_depth.
192 se_cmd
->scsi_status
= SAM_STAT_TASK_SET_FULL
;
197 return ft_queue_status(se_cmd
);
200 static void ft_execute_work(struct work_struct
*work
)
202 struct ft_cmd
*cmd
= container_of(work
, struct ft_cmd
, work
);
204 target_execute_cmd(&cmd
->se_cmd
);
208 * Receive write data frame.
210 void ft_recv_write_data(struct ft_cmd
*cmd
, struct fc_frame
*fp
)
212 struct se_cmd
*se_cmd
= &cmd
->se_cmd
;
213 struct fc_seq
*seq
= cmd
->seq
;
215 struct fc_lport
*lport
;
216 struct fc_frame_header
*fh
;
217 struct scatterlist
*sg
= NULL
;
223 struct page
*page
= NULL
;
230 fh
= fc_frame_header_get(fp
);
231 if (!(ntoh24(fh
->fh_f_ctl
) & FC_FC_REL_OFF
))
234 f_ctl
= ntoh24(fh
->fh_f_ctl
);
235 ep
= fc_seq_exch(seq
);
237 if (cmd
->was_ddp_setup
) {
241 * Since DDP (Large Rx offload) was setup for this request,
242 * payload is expected to be copied directly to user buffers.
244 buf
= fc_frame_payload_get(fp
, 1);
246 pr_err("%s: xid 0x%x, f_ctl 0x%x, cmd->sg %p, "
247 "cmd->sg_cnt 0x%x. DDP was setup"
248 " hence not expected to receive frame with "
249 "payload, Frame will be dropped if"
250 "'Sequence Initiative' bit in f_ctl is"
251 "not set\n", __func__
, ep
->xid
, f_ctl
,
252 se_cmd
->t_data_sg
, se_cmd
->t_data_nents
);
254 * Invalidate HW DDP context if it was setup for respective
255 * command. Invalidation of HW DDP context is requited in both
256 * situation (success and error).
258 ft_invl_hw_context(cmd
);
261 * If "Sequence Initiative (TSI)" bit set in f_ctl, means last
262 * write data frame is received successfully where payload is
263 * posted directly to user buffer and only the last frame's
264 * header is posted in receive queue.
266 * If "Sequence Initiative (TSI)" bit is not set, means error
267 * condition w.r.t. DDP, hence drop the packet and let explict
268 * ABORTS from other end of exchange timer trigger the recovery.
270 if (f_ctl
& FC_FC_SEQ_INIT
)
276 rel_off
= ntohl(fh
->fh_parm_offset
);
277 frame_len
= fr_len(fp
);
278 if (frame_len
<= sizeof(*fh
))
280 frame_len
-= sizeof(*fh
);
281 from
= fc_frame_payload_get(fp
, 0);
282 if (rel_off
>= se_cmd
->data_length
)
284 if (frame_len
+ rel_off
> se_cmd
->data_length
)
285 frame_len
= se_cmd
->data_length
- rel_off
;
288 * Setup to use first mem list entry, unless no data.
290 BUG_ON(frame_len
&& !se_cmd
->t_data_sg
);
292 sg
= se_cmd
->t_data_sg
;
293 mem_len
= sg
->length
;
294 mem_off
= sg
->offset
;
301 mem_len
= sg
->length
;
302 mem_off
= sg
->offset
;
305 if (rel_off
>= mem_len
) {
314 tlen
= min(mem_len
, frame_len
);
316 to
= kmap_atomic(page
+ (mem_off
>> PAGE_SHIFT
));
318 to
+= mem_off
& ~PAGE_MASK
;
319 tlen
= min(tlen
, (size_t)(PAGE_SIZE
-
320 (mem_off
& ~PAGE_MASK
)));
321 memcpy(to
, from
, tlen
);
322 kunmap_atomic(page_addr
);
328 cmd
->write_data_len
+= tlen
;
331 if (cmd
->write_data_len
== se_cmd
->data_length
) {
332 INIT_WORK(&cmd
->work
, ft_execute_work
);
333 queue_work(cmd
->sess
->tport
->tpg
->workqueue
, &cmd
->work
);
340 * Handle and cleanup any HW specific resources if
341 * received ABORTS, errors, timeouts.
343 void ft_invl_hw_context(struct ft_cmd
*cmd
)
346 struct fc_exch
*ep
= NULL
;
347 struct fc_lport
*lport
= NULL
;
352 /* Cleanup the DDP context in HW if DDP was setup */
353 if (cmd
->was_ddp_setup
&& seq
) {
354 ep
= fc_seq_exch(seq
);
357 if (lport
&& (ep
->xid
<= lport
->lro_xid
)) {
359 * "ddp_done" trigger invalidation of HW
360 * specific DDP context
362 cmd
->write_data_len
= lport
->tt
.ddp_done(lport
,
366 * Resetting same variable to indicate HW's
367 * DDP context has been invalidated to avoid
368 * re_invalidation of same context (context is
369 * identified using ep->xid)
371 cmd
->was_ddp_setup
= 0;