[deliverable/linux.git] / drivers / target / tcm_fc / tfc_io.c

/*
 * Copyright (c) 2010 Cisco Systems, Inc.
 *
 * Portions based on tcm_loop_fabric_scsi.c and libfc/fc_fcp.c
 *
 * Copyright (c) 2007 Intel Corporation. All rights reserved.
 * Copyright (c) 2008 Red Hat, Inc.  All rights reserved.
 * Copyright (c) 2008 Mike Christie
 * Copyright (c) 2009 Rising Tide, Inc.
 * Copyright (c) 2009 Linux-iSCSI.org
 * Copyright (c) 2009 Nicholas A. Bellinger <nab@linux-iscsi.org>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 */

/* XXX TBD some includes may be extraneous */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <generated/utsrelease.h>
#include <linux/utsname.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/kthread.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/configfs.h>
#include <linux/ctype.h>
#include <linux/hash.h>
#include <linux/ratelimit.h>
#include <asm/unaligned.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/libfc.h>
#include <scsi/fc_encode.h>

#include <target/target_core_base.h>
#include <target/target_core_fabric.h>
#include <target/target_core_configfs.h>
#include <target/configfs_macros.h>

#include "tcm_fc.h"

/*
 * Deliver read data back to initiator.
 * XXX TBD handle resource problems later.
 */
int ft_queue_data_in(struct se_cmd *se_cmd)
{
	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	struct fc_frame *fp = NULL;
	struct fc_exch *ep;
	struct fc_lport *lport;
	struct scatterlist *sg = NULL;
	size_t remaining;
	u32 f_ctl = FC_FC_EX_CTX | FC_FC_REL_OFF;
	u32 mem_off = 0;
	u32 fh_off = 0;
	u32 frame_off = 0;
	size_t frame_len = 0;
	size_t mem_len = 0;
	size_t tlen;
	size_t off_in_page;
	struct page *page = NULL;
	int use_sg;
	int error;
	void *page_addr;
	void *from;
	void *to = NULL;

	if (cmd->aborted)
		return 0;
	ep = fc_seq_exch(cmd->seq);
	lport = ep->lp;
	cmd->seq = lport->tt.seq_start_next(cmd->seq);

	remaining = se_cmd->data_length;

	/*
	 * Setup to use first mem list entry, unless no data.
	 */
	BUG_ON(remaining && !se_cmd->t_data_sg);
	if (remaining) {
		sg = se_cmd->t_data_sg;
		mem_len = sg->length;
		mem_off = sg->offset;
		page = sg_page(sg);
	}

	/* no scatter/gather in skb for odd word length due to fc_seq_send() */
	use_sg = !(remaining % 4);

	while (remaining) {
		if (!mem_len) {
			sg = sg_next(sg);
			mem_len = min((size_t)sg->length, remaining);
			mem_off = sg->offset;
			page = sg_page(sg);
		}
		if (!frame_len) {
			/*
			 * If lport's has capability of Large Send Offload LSO)
			 * , then allow 'frame_len' to be as big as 'lso_max'
			 * if indicated transfer length is >= lport->lso_max
			 */
			frame_len = (lport->seq_offload) ? lport->lso_max :
							  cmd->sess->max_frame;
			frame_len = min(frame_len, remaining);
			fp = fc_frame_alloc(lport, use_sg ? 0 : frame_len);
			if (!fp)
				return -ENOMEM;
			to = fc_frame_payload_get(fp, 0);
			fh_off = frame_off;
			frame_off += frame_len;
			/*
			 * Setup the frame's max payload which is used by base
			 * driver to indicate HW about max frame size, so that
			 * HW can do fragmentation appropriately based on
			 * "gso_max_size" of underline netdev.
			 */
			fr_max_payload(fp) = cmd->sess->max_frame;
		}
		tlen = min(mem_len, frame_len);

		if (use_sg) {
			off_in_page = mem_off;
			BUG_ON(!page);
			get_page(page);
			skb_fill_page_desc(fp_skb(fp),
					   skb_shinfo(fp_skb(fp))->nr_frags,
					   page, off_in_page, tlen);
			fr_len(fp) += tlen;
			fp_skb(fp)->data_len += tlen;
			fp_skb(fp)->truesize +=
					PAGE_SIZE << compound_order(page);
		} else {
			BUG_ON(!page);
			from = kmap_atomic(page + (mem_off >> PAGE_SHIFT));
			page_addr = from;
			from += mem_off & ~PAGE_MASK;
			tlen = min(tlen, (size_t)(PAGE_SIZE -
						(mem_off & ~PAGE_MASK)));
			memcpy(to, from, tlen);
			kunmap_atomic(page_addr);
			to += tlen;
		}

		mem_off += tlen;
		mem_len -= tlen;
		frame_len -= tlen;
		remaining -= tlen;

		if (frame_len &&
		    (skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN))
			continue;
		if (!remaining)
			f_ctl |= FC_FC_END_SEQ;
		fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
			       FC_TYPE_FCP, f_ctl, fh_off);
		error = lport->tt.seq_send(lport, cmd->seq, fp);
		if (error) {
			/* XXX For now, initiator will retry */
			pr_err_ratelimited("%s: Failed to send frame %p, "
						"xid <0x%x>, remaining %zu, "
						"lso_max <0x%x>\n",
						__func__, fp, ep->xid,
						remaining, lport->lso_max);
		}
	}
	return ft_queue_status(se_cmd);
}

static void ft_execute_work(struct work_struct *work)
{
	struct ft_cmd *cmd = container_of(work, struct ft_cmd, work);

	target_execute_cmd(&cmd->se_cmd);
}

/*
 * Receive write data frame.
 */
void ft_recv_write_data(struct ft_cmd *cmd, struct fc_frame *fp)
{
	struct se_cmd *se_cmd = &cmd->se_cmd;
	struct fc_seq *seq = cmd->seq;
	struct fc_exch *ep;
	struct fc_lport *lport;
	struct fc_frame_header *fh;
	struct scatterlist *sg = NULL;
	u32 mem_off = 0;
	u32 rel_off;
	size_t frame_len;
	size_t mem_len = 0;
	size_t tlen;
	struct page *page = NULL;
	void *page_addr;
	void *from;
	void *to;
	u32 f_ctl;
	void *buf;

	fh = fc_frame_header_get(fp);
	if (!(ntoh24(fh->fh_f_ctl) & FC_FC_REL_OFF))
		goto drop;

	f_ctl = ntoh24(fh->fh_f_ctl);
	ep = fc_seq_exch(seq);
	lport = ep->lp;
	if (cmd->was_ddp_setup) {
		BUG_ON(!ep);
		BUG_ON(!lport);
		/*
		 * Since DDP (Large Rx offload) was setup for this request,
		 * payload is expected to be copied directly to user buffers.
		 */
		buf = fc_frame_payload_get(fp, 1);
		if (buf)
			pr_err("%s: xid 0x%x, f_ctl 0x%x, cmd->sg %p, "
				"cmd->sg_cnt 0x%x. DDP was setup"
				" hence not expected to receive frame with "
				"payload, Frame will be dropped if"
				"'Sequence Initiative' bit in f_ctl is"
				"not set\n", __func__, ep->xid, f_ctl,
				se_cmd->t_data_sg, se_cmd->t_data_nents);
		/*
		 * Invalidate HW DDP context if it was setup for respective
		 * command. Invalidation of HW DDP context is requited in both
		 * situation (success and error).
		 */
		ft_invl_hw_context(cmd);

		/*
		 * If "Sequence Initiative (TSI)" bit set in f_ctl, means last
		 * write data frame is received successfully where payload is
		 * posted directly to user buffer and only the last frame's
		 * header is posted in receive queue.
		 *
		 * If "Sequence Initiative (TSI)" bit is not set, means error
		 * condition w.r.t. DDP, hence drop the packet and let explict
		 * ABORTS from other end of exchange timer trigger the recovery.
		 */
		if (f_ctl & FC_FC_SEQ_INIT)
			goto last_frame;
		else
			goto drop;
	}

	rel_off = ntohl(fh->fh_parm_offset);
	frame_len = fr_len(fp);
	if (frame_len <= sizeof(*fh))
		goto drop;
	frame_len -= sizeof(*fh);
	from = fc_frame_payload_get(fp, 0);
	if (rel_off >= se_cmd->data_length)
		goto drop;
	if (frame_len + rel_off > se_cmd->data_length)
		frame_len = se_cmd->data_length - rel_off;

	/*
	 * Setup to use first mem list entry, unless no data.
	 */
	BUG_ON(frame_len && !se_cmd->t_data_sg);
	if (frame_len) {
		sg = se_cmd->t_data_sg;
		mem_len = sg->length;
		mem_off = sg->offset;
		page = sg_page(sg);
	}

	while (frame_len) {
		if (!mem_len) {
			sg = sg_next(sg);
			mem_len = sg->length;
			mem_off = sg->offset;
			page = sg_page(sg);
		}
		if (rel_off >= mem_len) {
			rel_off -= mem_len;
			mem_len = 0;
			continue;
		}
		mem_off += rel_off;
		mem_len -= rel_off;
		rel_off = 0;

		tlen = min(mem_len, frame_len);

		to = kmap_atomic(page + (mem_off >> PAGE_SHIFT));
		page_addr = to;
		to += mem_off & ~PAGE_MASK;
		tlen = min(tlen, (size_t)(PAGE_SIZE -
					  (mem_off & ~PAGE_MASK)));
		memcpy(to, from, tlen);
		kunmap_atomic(page_addr);

		from += tlen;
		frame_len -= tlen;
		mem_off += tlen;
		mem_len -= tlen;
		cmd->write_data_len += tlen;
	}
last_frame:
	if (cmd->write_data_len == se_cmd->data_length) {
		INIT_WORK(&cmd->work, ft_execute_work);
		queue_work(cmd->sess->tport->tpg->workqueue, &cmd->work);
	}
drop:
	fc_frame_free(fp);
}

/*
 * Handle and cleanup any HW specific resources if
 * received ABORTS, errors, timeouts.
 */
void ft_invl_hw_context(struct ft_cmd *cmd)
{
	struct fc_seq *seq = cmd->seq;
	struct fc_exch *ep = NULL;
	struct fc_lport *lport = NULL;

	BUG_ON(!cmd);

	/* Cleanup the DDP context in HW if DDP was setup */
	if (cmd->was_ddp_setup && seq) {
		ep = fc_seq_exch(seq);
		if (ep) {
			lport = ep->lp;
			if (lport && (ep->xid <= lport->lro_xid))
				/*
				 * "ddp_done" trigger invalidation of HW
				 * specific DDP context
				 */
				cmd->write_data_len = lport->tt.ddp_done(lport,
								      ep->xid);

				/*
				 * Resetting same variable to indicate HW's
				 * DDP context has been invalidated to avoid
				 * re_invalidation of same context (context is
				 * identified using ep->xid)
				 */
				cmd->was_ddp_setup = 0;
		}
	}
}
Commit	Line	Data
3699d92a KP	1	/*
	2	* Copyright (c) 2010 Cisco Systems, Inc.
	3	*
	4	* Portions based on tcm_loop_fabric_scsi.c and libfc/fc_fcp.c
	5	*
	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>
	12	*
	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.
	16	*
	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
	20	* more details.
	21	*
	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.
	25	*/
	26
	27	/* XXX TBD some includes may be extraneous */
	28
	29	#include <linux/module.h>
	30	#include <linux/moduleparam.h>
3699d92a KP	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>
6708bb27	41	#include <linux/ratelimit.h>
3699d92a KP	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>
	49
	50	#include <target/target_core_base.h>
c4795fb2	51	#include <target/target_core_fabric.h>
3699d92a	52	#include <target/target_core_configfs.h>
3699d92a KP	53	#include <target/configfs_macros.h>
	54
	55	#include "tcm_fc.h"
	56
	57	/*
	58	* Deliver read data back to initiator.
	59	* XXX TBD handle resource problems later.
	60	*/
	61	int ft_queue_data_in(struct se_cmd *se_cmd)
	62	{
	63	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
3699d92a KP	64	struct fc_frame *fp = NULL;
	65	struct fc_exch *ep;
	66	struct fc_lport *lport;
ec98f782	67	struct scatterlist *sg = NULL;
3699d92a KP	68	size_t remaining;
3699d92a KP	69	u32 f_ctl = FC_FC_EX_CTX \| FC_FC_REL_OFF;
ec98f782	70	u32 mem_off = 0;
3699d92a KP	71	u32 fh_off = 0;
	72	u32 frame_off = 0;
	73	size_t frame_len = 0;
ec98f782	74	size_t mem_len = 0;
3699d92a KP	75	size_t tlen;
3699d92a KP	76	size_t off_in_page;
ec98f782	77	struct page *page = NULL;
3699d92a KP	78	int use_sg;
	79	int error;
	80	void *page_addr;
	81	void *from;
	82	void *to = NULL;
	83
e1c40382 MR	84	if (cmd->aborted)
e1c40382 MR	85	return 0;
3699d92a KP	86	ep = fc_seq_exch(cmd->seq);
	87	lport = ep->lp;
	88	cmd->seq = lport->tt.seq_start_next(cmd->seq);
	89
3699d92a KP	90	remaining = se_cmd->data_length;
	91
	92	/*
05d1c7c0	93	* Setup to use first mem list entry, unless no data.
3699d92a	94	*/
ec98f782	95	BUG_ON(remaining && !se_cmd->t_data_sg);
05d1c7c0	96	if (remaining) {
ec98f782 AG	97	sg = se_cmd->t_data_sg;
	98	mem_len = sg->length;
	99	mem_off = sg->offset;
	100	page = sg_page(sg);
3699d92a KP	101	}
	102
	103	/* no scatter/gather in skb for odd word length due to fc_seq_send() */
	104	use_sg = !(remaining % 4);
	105
	106	while (remaining) {
	107	if (!mem_len) {
ec98f782 AG	108	sg = sg_next(sg);
	109	mem_len = min((size_t)sg->length, remaining);
	110	mem_off = sg->offset;
	111	page = sg_page(sg);
3699d92a KP	112	}
	113	if (!frame_len) {
	114	/*
	115	* If lport's has capability of Large Send Offload LSO)
	116	* , then allow 'frame_len' to be as big as 'lso_max'
	117	* if indicated transfer length is >= lport->lso_max
	118	*/
	119	frame_len = (lport->seq_offload) ? lport->lso_max :
	120	cmd->sess->max_frame;
	121	frame_len = min(frame_len, remaining);
	122	fp = fc_frame_alloc(lport, use_sg ? 0 : frame_len);
	123	if (!fp)
	124	return -ENOMEM;
	125	to = fc_frame_payload_get(fp, 0);
	126	fh_off = frame_off;
	127	frame_off += frame_len;
	128	/*
	129	* Setup the frame's max payload which is used by base
	130	* driver to indicate HW about max frame size, so that
	131	* HW can do fragmentation appropriately based on
	132	* "gso_max_size" of underline netdev.
	133	*/
	134	fr_max_payload(fp) = cmd->sess->max_frame;
	135	}
	136	tlen = min(mem_len, frame_len);
	137
	138	if (use_sg) {
05d1c7c0	139	off_in_page = mem_off;
3699d92a KP	140	BUG_ON(!page);
	141	get_page(page);
	142	skb_fill_page_desc(fp_skb(fp),
	143	skb_shinfo(fp_skb(fp))->nr_frags,
	144	page, off_in_page, tlen);
	145	fr_len(fp) += tlen;
	146	fp_skb(fp)->data_len += tlen;
	147	fp_skb(fp)->truesize +=
	148	PAGE_SIZE << compound_order(page);
05d1c7c0	149	} else {
3699d92a	150	BUG_ON(!page);
ca747d61	151	from = kmap_atomic(page + (mem_off >> PAGE_SHIFT));
3699d92a KP	152	page_addr = from;
	153	from += mem_off & ~PAGE_MASK;
	154	tlen = min(tlen, (size_t)(PAGE_SIZE -
	155	(mem_off & ~PAGE_MASK)));
	156	memcpy(to, from, tlen);
ca747d61	157	kunmap_atomic(page_addr);
3699d92a	158	to += tlen;
3699d92a KP	159	}
	160
	161	mem_off += tlen;
	162	mem_len -= tlen;
	163	frame_len -= tlen;
	164	remaining -= tlen;
	165
	166	if (frame_len &&
	167	(skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN))
	168	continue;
	169	if (!remaining)
	170	f_ctl \|= FC_FC_END_SEQ;
	171	fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
	172	FC_TYPE_FCP, f_ctl, fh_off);
	173	error = lport->tt.seq_send(lport, cmd->seq, fp);
	174	if (error) {
	175	/* XXX For now, initiator will retry */
6708bb27	176	pr_err_ratelimited("%s: Failed to send frame %p, "
95efa286	177	"xid <0x%x>, remaining %zu, "
3699d92a KP	178	"lso_max <0x%x>\n",
	179	__func__, fp, ep->xid,
	180	remaining, lport->lso_max);
	181	}
	182	}
	183	return ft_queue_status(se_cmd);
	184	}
	185
b8b22533 CH	186	static void ft_execute_work(struct work_struct *work)
	187	{
	188	struct ft_cmd *cmd = container_of(work, struct ft_cmd, work);
	189
	190	target_execute_cmd(&cmd->se_cmd);
	191	}
	192
3699d92a KP	193	/*
	194	* Receive write data frame.
	195	*/
	196	void ft_recv_write_data(struct ft_cmd cmd, struct fc_frame fp)
	197	{
	198	struct se_cmd *se_cmd = &cmd->se_cmd;
	199	struct fc_seq *seq = cmd->seq;
	200	struct fc_exch *ep;
	201	struct fc_lport *lport;
3699d92a	202	struct fc_frame_header *fh;
ec98f782 AG	203	struct scatterlist *sg = NULL;
ec98f782 AG	204	u32 mem_off = 0;
3699d92a KP	205	u32 rel_off;
3699d92a KP	206	size_t frame_len;
ec98f782	207	size_t mem_len = 0;
3699d92a	208	size_t tlen;
ec98f782	209	struct page *page = NULL;
3699d92a KP	210	void *page_addr;
	211	void *from;
	212	void *to;
	213	u32 f_ctl;
	214	void *buf;
	215
3699d92a KP	216	fh = fc_frame_header_get(fp);
	217	if (!(ntoh24(fh->fh_f_ctl) & FC_FC_REL_OFF))
	218	goto drop;
	219
dcd998cc KP	220	f_ctl = ntoh24(fh->fh_f_ctl);
	221	ep = fc_seq_exch(seq);
	222	lport = ep->lp;
	223	if (cmd->was_ddp_setup) {
	224	BUG_ON(!ep);
	225	BUG_ON(!lport);
079587b4 KP	226	/*
	227	* Since DDP (Large Rx offload) was setup for this request,
	228	* payload is expected to be copied directly to user buffers.
	229	*/
	230	buf = fc_frame_payload_get(fp, 1);
	231	if (buf)
	232	pr_err("%s: xid 0x%x, f_ctl 0x%x, cmd->sg %p, "
dcd998cc KP	233	"cmd->sg_cnt 0x%x. DDP was setup"
dcd998cc KP	234	" hence not expected to receive frame with "
079587b4 KP	235	"payload, Frame will be dropped if"
079587b4 KP	236	"'Sequence Initiative' bit in f_ctl is"
dcd998cc	237	"not set\n", __func__, ep->xid, f_ctl,
e182d682	238	se_cmd->t_data_sg, se_cmd->t_data_nents);
079587b4 KP	239	/*
	240	* Invalidate HW DDP context if it was setup for respective
	241	* command. Invalidation of HW DDP context is requited in both
	242	* situation (success and error).
	243	*/
	244	ft_invl_hw_context(cmd);
3699d92a	245
079587b4 KP	246	/*
	247	* If "Sequence Initiative (TSI)" bit set in f_ctl, means last
	248	* write data frame is received successfully where payload is
	249	* posted directly to user buffer and only the last frame's
	250	* header is posted in receive queue.
	251	*
	252	* If "Sequence Initiative (TSI)" bit is not set, means error
	253	* condition w.r.t. DDP, hence drop the packet and let explict
	254	* ABORTS from other end of exchange timer trigger the recovery.
	255	*/
	256	if (f_ctl & FC_FC_SEQ_INIT)
	257	goto last_frame;
	258	else
	259	goto drop;
	260	}
3699d92a KP	261
	262	rel_off = ntohl(fh->fh_parm_offset);
	263	frame_len = fr_len(fp);
	264	if (frame_len <= sizeof(*fh))
	265	goto drop;
	266	frame_len -= sizeof(*fh);
	267	from = fc_frame_payload_get(fp, 0);
	268	if (rel_off >= se_cmd->data_length)
	269	goto drop;
	270	if (frame_len + rel_off > se_cmd->data_length)
	271	frame_len = se_cmd->data_length - rel_off;
	272
	273	/*
05d1c7c0	274	* Setup to use first mem list entry, unless no data.
3699d92a	275	*/
ec98f782	276	BUG_ON(frame_len && !se_cmd->t_data_sg);
05d1c7c0	277	if (frame_len) {
ec98f782 AG	278	sg = se_cmd->t_data_sg;
	279	mem_len = sg->length;
	280	mem_off = sg->offset;
	281	page = sg_page(sg);
3699d92a KP	282	}
	283
	284	while (frame_len) {
	285	if (!mem_len) {
ec98f782 AG	286	sg = sg_next(sg);
	287	mem_len = sg->length;
	288	mem_off = sg->offset;
	289	page = sg_page(sg);
3699d92a KP	290	}
	291	if (rel_off >= mem_len) {
	292	rel_off -= mem_len;
	293	mem_len = 0;
	294	continue;
	295	}
	296	mem_off += rel_off;
	297	mem_len -= rel_off;
	298	rel_off = 0;
	299
	300	tlen = min(mem_len, frame_len);
	301
ca747d61	302	to = kmap_atomic(page + (mem_off >> PAGE_SHIFT));
05d1c7c0 AG	303	page_addr = to;
	304	to += mem_off & ~PAGE_MASK;
	305	tlen = min(tlen, (size_t)(PAGE_SIZE -
	306	(mem_off & ~PAGE_MASK)));
	307	memcpy(to, from, tlen);
ca747d61	308	kunmap_atomic(page_addr);
05d1c7c0	309
3699d92a KP	310	from += tlen;
	311	frame_len -= tlen;
	312	mem_off += tlen;
	313	mem_len -= tlen;
	314	cmd->write_data_len += tlen;
	315	}
	316	last_frame:
b8b22533 CH	317	if (cmd->write_data_len == se_cmd->data_length) {
	318	INIT_WORK(&cmd->work, ft_execute_work);
	319	queue_work(cmd->sess->tport->tpg->workqueue, &cmd->work);
	320	}
3699d92a KP	321	drop:
	322	fc_frame_free(fp);
	323	}
dcd998cc KP	324
	325	/*
	326	* Handle and cleanup any HW specific resources if
	327	* received ABORTS, errors, timeouts.
	328	*/
	329	void ft_invl_hw_context(struct ft_cmd *cmd)
	330	{
	331	struct fc_seq *seq = cmd->seq;
	332	struct fc_exch *ep = NULL;
	333	struct fc_lport *lport = NULL;
	334
	335	BUG_ON(!cmd);
	336
	337	/* Cleanup the DDP context in HW if DDP was setup */
	338	if (cmd->was_ddp_setup && seq) {
	339	ep = fc_seq_exch(seq);
	340	if (ep) {
	341	lport = ep->lp;
	342	if (lport && (ep->xid <= lport->lro_xid))
	343	/*
	344	* "ddp_done" trigger invalidation of HW
	345	* specific DDP context
	346	*/
	347	cmd->write_data_len = lport->tt.ddp_done(lport,
	348	ep->xid);
	349
	350	/*
	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)
	355	*/
	356	cmd->was_ddp_setup = 0;
	357	}
	358	}
	359	}