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 <generated/utsrelease.h>
32 #include <linux/utsname.h>
33 #include <linux/init.h>
34 #include <linux/slab.h>
35 #include <linux/kthread.h>
36 #include <linux/types.h>
37 #include <linux/string.h>
38 #include <linux/configfs.h>
39 #include <linux/ctype.h>
40 #include <linux/hash.h>
41 #include <linux/ratelimit.h>
42 #include <asm/unaligned.h>
43 #include <scsi/scsi.h>
44 #include <scsi/scsi_host.h>
45 #include <scsi/scsi_device.h>
46 #include <scsi/scsi_cmnd.h>
47 #include <scsi/libfc.h>
48 #include <scsi/fc_encode.h>
50 #include <target/target_core_base.h>
51 #include <target/target_core_transport.h>
52 #include <target/target_core_fabric_ops.h>
53 #include <target/target_core_device.h>
54 #include <target/target_core_tpg.h>
55 #include <target/target_core_configfs.h>
56 #include <target/configfs_macros.h>
61 * Deliver read data back to initiator.
62 * XXX TBD handle resource problems later.
64 int ft_queue_data_in(struct se_cmd *se_cmd)
66 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
67 struct fc_frame *fp = NULL;
69 struct fc_lport *lport;
70 struct scatterlist *sg = NULL;
72 u32 f_ctl = FC_FC_EX_CTX | FC_FC_REL_OFF;
80 struct page *page = NULL;
87 ep = fc_seq_exch(cmd->seq);
89 cmd->seq = lport->tt.seq_start_next(cmd->seq);
91 remaining = se_cmd->data_length;
94 * Setup to use first mem list entry, unless no data.
96 BUG_ON(remaining && !se_cmd->t_data_sg);
98 sg = se_cmd->t_data_sg;
100 mem_off = sg->offset;
104 /* no scatter/gather in skb for odd word length due to fc_seq_send() */
105 use_sg = !(remaining % 4);
110 mem_len = min((size_t)sg->length, remaining);
111 mem_off = sg->offset;
116 * If lport's has capability of Large Send Offload LSO)
117 * , then allow 'frame_len' to be as big as 'lso_max'
118 * if indicated transfer length is >= lport->lso_max
120 frame_len = (lport->seq_offload) ? lport->lso_max :
121 cmd->sess->max_frame;
122 frame_len = min(frame_len, remaining);
123 fp = fc_frame_alloc(lport, use_sg ? 0 : frame_len);
126 to = fc_frame_payload_get(fp, 0);
128 frame_off += frame_len;
130 * Setup the frame's max payload which is used by base
131 * driver to indicate HW about max frame size, so that
132 * HW can do fragmentation appropriately based on
133 * "gso_max_size" of underline netdev.
135 fr_max_payload(fp) = cmd->sess->max_frame;
137 tlen = min(mem_len, frame_len);
140 off_in_page = mem_off;
143 skb_fill_page_desc(fp_skb(fp),
144 skb_shinfo(fp_skb(fp))->nr_frags,
145 page, off_in_page, tlen);
147 fp_skb(fp)->data_len += tlen;
148 fp_skb(fp)->truesize +=
149 PAGE_SIZE << compound_order(page);
152 from = kmap_atomic(page + (mem_off >> PAGE_SHIFT),
155 from += mem_off & ~PAGE_MASK;
156 tlen = min(tlen, (size_t)(PAGE_SIZE -
157 (mem_off & ~PAGE_MASK)));
158 memcpy(to, from, tlen);
159 kunmap_atomic(page_addr, KM_SOFTIRQ0);
169 (skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN))
172 f_ctl |= FC_FC_END_SEQ;
173 fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
174 FC_TYPE_FCP, f_ctl, fh_off);
175 error = lport->tt.seq_send(lport, cmd->seq, fp);
177 /* XXX For now, initiator will retry */
178 pr_err_ratelimited("%s: Failed to send frame %p, "
179 "xid <0x%x>, remaining %zu, "
181 __func__, fp, ep->xid,
182 remaining, lport->lso_max);
185 return ft_queue_status(se_cmd);
189 * Receive write data frame.
191 void ft_recv_write_data(struct ft_cmd *cmd, struct fc_frame *fp)
193 struct se_cmd *se_cmd = &cmd->se_cmd;
194 struct fc_seq *seq = cmd->seq;
196 struct fc_lport *lport;
197 struct fc_frame_header *fh;
198 struct scatterlist *sg = NULL;
204 struct page *page = NULL;
211 fh = fc_frame_header_get(fp);
212 if (!(ntoh24(fh->fh_f_ctl) & FC_FC_REL_OFF))
215 f_ctl = ntoh24(fh->fh_f_ctl);
216 ep = fc_seq_exch(seq);
218 if (cmd->was_ddp_setup) {
224 * Doesn't expect payload if DDP is setup. Payload
225 * is expected to be copied directly to user buffers
226 * due to DDP (Large Rx offload),
228 buf = fc_frame_payload_get(fp, 1);
230 pr_err("%s: xid 0x%x, f_ctl 0x%x, cmd->sg %p, "
231 "cmd->sg_cnt 0x%x. DDP was setup"
232 " hence not expected to receive frame with "
233 "payload, Frame will be dropped if "
234 "'Sequence Initiative' bit in f_ctl is "
235 "not set\n", __func__, ep->xid, f_ctl,
236 cmd->sg, cmd->sg_cnt);
238 * Invalidate HW DDP context if it was setup for respective
239 * command. Invalidation of HW DDP context is requited in both
240 * situation (success and error).
242 ft_invl_hw_context(cmd);
245 * If "Sequence Initiative (TSI)" bit set in f_ctl, means last
246 * write data frame is received successfully where payload is
247 * posted directly to user buffer and only the last frame's
248 * header is posted in receive queue.
250 * If "Sequence Initiative (TSI)" bit is not set, means error
251 * condition w.r.t. DDP, hence drop the packet and let explict
252 * ABORTS from other end of exchange timer trigger the recovery.
254 if (f_ctl & FC_FC_SEQ_INIT)
259 rel_off = ntohl(fh->fh_parm_offset);
260 frame_len = fr_len(fp);
261 if (frame_len <= sizeof(*fh))
263 frame_len -= sizeof(*fh);
264 from = fc_frame_payload_get(fp, 0);
265 if (rel_off >= se_cmd->data_length)
267 if (frame_len + rel_off > se_cmd->data_length)
268 frame_len = se_cmd->data_length - rel_off;
271 * Setup to use first mem list entry, unless no data.
273 BUG_ON(frame_len && !se_cmd->t_data_sg);
275 sg = se_cmd->t_data_sg;
276 mem_len = sg->length;
277 mem_off = sg->offset;
284 mem_len = sg->length;
285 mem_off = sg->offset;
288 if (rel_off >= mem_len) {
297 tlen = min(mem_len, frame_len);
299 to = kmap_atomic(page + (mem_off >> PAGE_SHIFT),
302 to += mem_off & ~PAGE_MASK;
303 tlen = min(tlen, (size_t)(PAGE_SIZE -
304 (mem_off & ~PAGE_MASK)));
305 memcpy(to, from, tlen);
306 kunmap_atomic(page_addr, KM_SOFTIRQ0);
312 cmd->write_data_len += tlen;
315 if (cmd->write_data_len == se_cmd->data_length)
316 transport_generic_handle_data(se_cmd);
322 * Handle and cleanup any HW specific resources if
323 * received ABORTS, errors, timeouts.
325 void ft_invl_hw_context(struct ft_cmd *cmd)
327 struct fc_seq *seq = cmd->seq;
328 struct fc_exch *ep = NULL;
329 struct fc_lport *lport = NULL;
333 /* Cleanup the DDP context in HW if DDP was setup */
334 if (cmd->was_ddp_setup && seq) {
335 ep = fc_seq_exch(seq);
338 if (lport && (ep->xid <= lport->lro_xid))
340 * "ddp_done" trigger invalidation of HW
341 * specific DDP context
343 cmd->write_data_len = lport->tt.ddp_done(lport,
347 * Resetting same variable to indicate HW's
348 * DDP context has been invalidated to avoid
349 * re_invalidation of same context (context is
350 * identified using ep->xid)
352 cmd->was_ddp_setup = 0;