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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (c) 2010 Cisco Systems, Inc.4 *5 * Portions based on tcm_loop_fabric_scsi.c and libfc/fc_fcp.c6 *7 * Copyright (c) 2007 Intel Corporation. All rights reserved.8 * Copyright (c) 2008 Red Hat, Inc. All rights reserved.9 * Copyright (c) 2008 Mike Christie10 * Copyright (c) 2009 Rising Tide, Inc.11 * Copyright (c) 2009 Linux-iSCSI.org12 * Copyright (c) 2009 Nicholas A. Bellinger <nab@linux-iscsi.org>13 */14 15/* XXX TBD some includes may be extraneous */16 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 <linux/unaligned.h>30#include <scsi/libfc.h>31 32#include <target/target_core_base.h>33#include <target/target_core_fabric.h>34 35#include "tcm_fc.h"36 37/*38 * Deliver read data back to initiator.39 * XXX TBD handle resource problems later.40 */41int ft_queue_data_in(struct se_cmd *se_cmd)42{43 struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);44 struct fc_frame *fp = NULL;45 struct fc_exch *ep;46 struct fc_lport *lport;47 struct scatterlist *sg = NULL;48 size_t remaining;49 u32 f_ctl = FC_FC_EX_CTX | FC_FC_REL_OFF;50 u32 mem_off = 0;51 u32 fh_off = 0;52 u32 frame_off = 0;53 size_t frame_len = 0;54 size_t mem_len = 0;55 size_t tlen;56 size_t off_in_page;57 struct page *page = NULL;58 int use_sg;59 int error;60 void *page_addr;61 void *from;62 void *to = NULL;63 64 if (cmd->aborted)65 return 0;66 67 if (se_cmd->scsi_status == SAM_STAT_TASK_SET_FULL)68 goto queue_status;69 70 ep = fc_seq_exch(cmd->seq);71 lport = ep->lp;72 cmd->seq = fc_seq_start_next(cmd->seq);73 74 remaining = se_cmd->data_length;75 76 /*77 * Setup to use first mem list entry, unless no data.78 */79 BUG_ON(remaining && !se_cmd->t_data_sg);80 if (remaining) {81 sg = se_cmd->t_data_sg;82 mem_len = sg->length;83 mem_off = sg->offset;84 page = sg_page(sg);85 }86 87 /* no scatter/gather in skb for odd word length due to fc_seq_send() */88 use_sg = !(remaining % 4);89 90 while (remaining) {91 struct fc_seq *seq = cmd->seq;92 93 if (!seq) {94 pr_debug("%s: Command aborted, xid 0x%x\n",95 __func__, ep->xid);96 break;97 }98 if (!mem_len) {99 sg = sg_next(sg);100 mem_len = min((size_t)sg->length, remaining);101 mem_off = sg->offset;102 page = sg_page(sg);103 }104 if (!frame_len) {105 /*106 * If lport's has capability of Large Send Offload LSO)107 * , then allow 'frame_len' to be as big as 'lso_max'108 * if indicated transfer length is >= lport->lso_max109 */110 frame_len = (lport->seq_offload) ? lport->lso_max :111 cmd->sess->max_frame;112 frame_len = min(frame_len, remaining);113 fp = fc_frame_alloc(lport, use_sg ? 0 : frame_len);114 if (!fp)115 return -ENOMEM;116 to = fc_frame_payload_get(fp, 0);117 fh_off = frame_off;118 frame_off += frame_len;119 /*120 * Setup the frame's max payload which is used by base121 * driver to indicate HW about max frame size, so that122 * HW can do fragmentation appropriately based on123 * "gso_max_size" of underline netdev.124 */125 fr_max_payload(fp) = cmd->sess->max_frame;126 }127 tlen = min(mem_len, frame_len);128 129 if (use_sg) {130 off_in_page = mem_off;131 BUG_ON(!page);132 get_page(page);133 skb_fill_page_desc(fp_skb(fp),134 skb_shinfo(fp_skb(fp))->nr_frags,135 page, off_in_page, tlen);136 fr_len(fp) += tlen;137 fp_skb(fp)->data_len += tlen;138 fp_skb(fp)->truesize += page_size(page);139 } else {140 BUG_ON(!page);141 from = kmap_atomic(page + (mem_off >> PAGE_SHIFT));142 page_addr = from;143 from += offset_in_page(mem_off);144 tlen = min(tlen, (size_t)(PAGE_SIZE -145 offset_in_page(mem_off)));146 memcpy(to, from, tlen);147 kunmap_atomic(page_addr);148 to += tlen;149 }150 151 mem_off += tlen;152 mem_len -= tlen;153 frame_len -= tlen;154 remaining -= tlen;155 156 if (frame_len &&157 (skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN))158 continue;159 if (!remaining)160 f_ctl |= FC_FC_END_SEQ;161 fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,162 FC_TYPE_FCP, f_ctl, fh_off);163 error = fc_seq_send(lport, seq, fp);164 if (error) {165 pr_info_ratelimited("%s: Failed to send frame %p, "166 "xid <0x%x>, remaining %zu, "167 "lso_max <0x%x>\n",168 __func__, fp, ep->xid,169 remaining, lport->lso_max);170 /*171 * Go ahead and set TASK_SET_FULL status ignoring the172 * rest of the DataIN, and immediately attempt to173 * send the response via ft_queue_status() in order174 * to notify the initiator that it should reduce it's175 * per LUN queue_depth.176 */177 se_cmd->scsi_status = SAM_STAT_TASK_SET_FULL;178 break;179 }180 }181queue_status:182 return ft_queue_status(se_cmd);183}184 185static void ft_execute_work(struct work_struct *work)186{187 struct ft_cmd *cmd = container_of(work, struct ft_cmd, work);188 189 target_execute_cmd(&cmd->se_cmd);190}191 192/*193 * Receive write data frame.194 */195void ft_recv_write_data(struct ft_cmd *cmd, struct fc_frame *fp)196{197 struct se_cmd *se_cmd = &cmd->se_cmd;198 struct fc_seq *seq = cmd->seq;199 struct fc_exch *ep;200 struct fc_lport *lport;201 struct fc_frame_header *fh;202 struct scatterlist *sg = NULL;203 u32 mem_off = 0;204 u32 rel_off;205 size_t frame_len;206 size_t mem_len = 0;207 size_t tlen;208 struct page *page = NULL;209 void *page_addr;210 void *from;211 void *to;212 u32 f_ctl;213 void *buf;214 215 fh = fc_frame_header_get(fp);216 if (!(ntoh24(fh->fh_f_ctl) & FC_FC_REL_OFF))217 goto drop;218 219 f_ctl = ntoh24(fh->fh_f_ctl);220 ep = fc_seq_exch(seq);221 lport = ep->lp;222 if (cmd->was_ddp_setup) {223 BUG_ON(!lport);224 /*225 * Since DDP (Large Rx offload) was setup for this request,226 * payload is expected to be copied directly to user buffers.227 */228 buf = fc_frame_payload_get(fp, 1);229 if (buf)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 se_cmd->t_data_sg, se_cmd->t_data_nents);237 /*238 * Invalidate HW DDP context if it was setup for respective239 * command. Invalidation of HW DDP context is requited in both240 * situation (success and error).241 */242 ft_invl_hw_context(cmd);243 244 /*245 * If "Sequence Initiative (TSI)" bit set in f_ctl, means last246 * write data frame is received successfully where payload is247 * posted directly to user buffer and only the last frame's248 * header is posted in receive queue.249 *250 * If "Sequence Initiative (TSI)" bit is not set, means error251 * condition w.r.t. DDP, hence drop the packet and let explict252 * ABORTS from other end of exchange timer trigger the recovery.253 */254 if (f_ctl & FC_FC_SEQ_INIT)255 goto last_frame;256 else257 goto drop;258 }259 260 rel_off = ntohl(fh->fh_parm_offset);261 frame_len = fr_len(fp);262 if (frame_len <= sizeof(*fh))263 goto drop;264 frame_len -= sizeof(*fh);265 from = fc_frame_payload_get(fp, 0);266 if (rel_off >= se_cmd->data_length)267 goto drop;268 if (frame_len + rel_off > se_cmd->data_length)269 frame_len = se_cmd->data_length - rel_off;270 271 /*272 * Setup to use first mem list entry, unless no data.273 */274 BUG_ON(frame_len && !se_cmd->t_data_sg);275 if (frame_len) {276 sg = se_cmd->t_data_sg;277 mem_len = sg->length;278 mem_off = sg->offset;279 page = sg_page(sg);280 }281 282 while (frame_len) {283 if (!mem_len) {284 sg = sg_next(sg);285 mem_len = sg->length;286 mem_off = sg->offset;287 page = sg_page(sg);288 }289 if (rel_off >= mem_len) {290 rel_off -= mem_len;291 mem_len = 0;292 continue;293 }294 mem_off += rel_off;295 mem_len -= rel_off;296 rel_off = 0;297 298 tlen = min(mem_len, frame_len);299 300 to = kmap_atomic(page + (mem_off >> PAGE_SHIFT));301 page_addr = to;302 to += offset_in_page(mem_off);303 tlen = min(tlen, (size_t)(PAGE_SIZE -304 offset_in_page(mem_off)));305 memcpy(to, from, tlen);306 kunmap_atomic(page_addr);307 308 from += tlen;309 frame_len -= tlen;310 mem_off += tlen;311 mem_len -= tlen;312 cmd->write_data_len += tlen;313 }314last_frame:315 if (cmd->write_data_len == se_cmd->data_length) {316 INIT_WORK(&cmd->work, ft_execute_work);317 queue_work(cmd->sess->tport->tpg->workqueue, &cmd->work);318 }319drop:320 fc_frame_free(fp);321}322 323/*324 * Handle and cleanup any HW specific resources if325 * received ABORTS, errors, timeouts.326 */327void ft_invl_hw_context(struct ft_cmd *cmd)328{329 struct fc_seq *seq;330 struct fc_exch *ep = NULL;331 struct fc_lport *lport = NULL;332 333 BUG_ON(!cmd);334 seq = cmd->seq;335 336 /* Cleanup the DDP context in HW if DDP was setup */337 if (cmd->was_ddp_setup && seq) {338 ep = fc_seq_exch(seq);339 if (ep) {340 lport = ep->lp;341 if (lport && (ep->xid <= lport->lro_xid)) {342 /*343 * "ddp_done" trigger invalidation of HW344 * specific DDP context345 */346 cmd->write_data_len = lport->tt.ddp_done(lport,347 ep->xid);348 349 /*350 * Resetting same variable to indicate HW's351 * DDP context has been invalidated to avoid352 * re_invalidation of same context (context is353 * identified using ep->xid)354 */355 cmd->was_ddp_setup = 0;356 }357 }358 }359}360