fc_fcp.c 52.6 KB
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/*
 * Copyright(c) 2007 Intel Corporation. All rights reserved.
 * Copyright(c) 2008 Red Hat, Inc.  All rights reserved.
 * Copyright(c) 2008 Mike Christie
 *
 * 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.
 *
 * Maintained at www.Open-FCoE.org
 */

#include <linux/module.h>
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/scatterlist.h>
#include <linux/err.h>
#include <linux/crc32.h>

#include <scsi/scsi_tcq.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>

#include <scsi/fc/fc_fc2.h>

#include <scsi/libfc.h>
#include <scsi/fc_encode.h>

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#include "fc_libfc.h"
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struct kmem_cache *scsi_pkt_cachep;
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/* SRB state definitions */
#define FC_SRB_FREE		0		/* cmd is free */
#define FC_SRB_CMD_SENT		(1 << 0)	/* cmd has been sent */
#define FC_SRB_RCV_STATUS	(1 << 1)	/* response has arrived */
#define FC_SRB_ABORT_PENDING	(1 << 2)	/* cmd abort sent to device */
#define FC_SRB_ABORTED		(1 << 3)	/* abort acknowleged */
#define FC_SRB_DISCONTIG	(1 << 4)	/* non-sequential data recvd */
#define FC_SRB_COMPL		(1 << 5)	/* fc_io_compl has been run */
#define FC_SRB_FCP_PROCESSING_TMO (1 << 6)	/* timer function processing */
#define FC_SRB_NOMEM		(1 << 7)	/* dropped to out of mem */

#define FC_SRB_READ		(1 << 1)
#define FC_SRB_WRITE		(1 << 0)

/*
 * The SCp.ptr should be tested and set under the host lock. NULL indicates
 * that the command has been retruned to the scsi layer.
 */
#define CMD_SP(Cmnd)		    ((struct fc_fcp_pkt *)(Cmnd)->SCp.ptr)
#define CMD_ENTRY_STATUS(Cmnd)	    ((Cmnd)->SCp.have_data_in)
#define CMD_COMPL_STATUS(Cmnd)	    ((Cmnd)->SCp.this_residual)
#define CMD_SCSI_STATUS(Cmnd)	    ((Cmnd)->SCp.Status)
#define CMD_RESID_LEN(Cmnd)	    ((Cmnd)->SCp.buffers_residual)

struct fc_fcp_internal {
	mempool_t	*scsi_pkt_pool;
	struct list_head scsi_pkt_queue;
	u8		throttled;
};

#define fc_get_scsi_internal(x)	((struct fc_fcp_internal *)(x)->scsi_priv)

/*
 * function prototypes
 * FC scsi I/O related functions
 */
static void fc_fcp_recv_data(struct fc_fcp_pkt *, struct fc_frame *);
static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *);
static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *);
static void fc_fcp_complete_locked(struct fc_fcp_pkt *);
static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *);
static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp);
static void fc_timeout_error(struct fc_fcp_pkt *);
static void fc_fcp_timeout(unsigned long data);
static void fc_fcp_rec(struct fc_fcp_pkt *);
static void fc_fcp_rec_error(struct fc_fcp_pkt *, struct fc_frame *);
static void fc_fcp_rec_resp(struct fc_seq *, struct fc_frame *, void *);
static void fc_io_compl(struct fc_fcp_pkt *);

static void fc_fcp_srr(struct fc_fcp_pkt *, enum fc_rctl, u32);
static void fc_fcp_srr_resp(struct fc_seq *, struct fc_frame *, void *);
static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);

/*
 * command status codes
 */
#define FC_COMPLETE		0
#define FC_CMD_ABORTED		1
#define FC_CMD_RESET		2
#define FC_CMD_PLOGO		3
#define FC_SNS_RCV		4
#define FC_TRANS_ERR		5
#define FC_DATA_OVRRUN		6
#define FC_DATA_UNDRUN		7
#define FC_ERROR		8
#define FC_HRD_ERROR		9
#define FC_CMD_TIME_OUT		10

/*
 * Error recovery timeout values.
 */
#define FC_SCSI_ER_TIMEOUT	(10 * HZ)
#define FC_SCSI_TM_TOV		(10 * HZ)
#define FC_SCSI_REC_TOV		(2 * HZ)
#define FC_HOST_RESET_TIMEOUT	(30 * HZ)

#define FC_MAX_ERROR_CNT	5
#define FC_MAX_RECOV_RETRY	3

#define FC_FCP_DFLT_QUEUE_DEPTH 32

/**
 * fc_fcp_pkt_alloc - allocation routine for scsi_pkt packet
 * @lp:		fc lport struct
 * @gfp:	gfp flags for allocation
 *
 * This is used by upper layer scsi driver.
 * Return Value : scsi_pkt structure or null on allocation failure.
 * Context	: call from process context. no locking required.
 */
static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lp, gfp_t gfp)
{
	struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
	struct fc_fcp_pkt *fsp;

	fsp = mempool_alloc(si->scsi_pkt_pool, gfp);
	if (fsp) {
		memset(fsp, 0, sizeof(*fsp));
		fsp->lp = lp;
		atomic_set(&fsp->ref_cnt, 1);
		init_timer(&fsp->timer);
		INIT_LIST_HEAD(&fsp->list);
		spin_lock_init(&fsp->scsi_pkt_lock);
	}
	return fsp;
}

/**
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 * fc_fcp_pkt_release() - release hold on scsi_pkt packet
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 * @fsp:	fcp packet struct
 *
 * This is used by upper layer scsi driver.
 * Context	: call from process  and interrupt context.
 *		  no locking required
 */
static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp)
{
	if (atomic_dec_and_test(&fsp->ref_cnt)) {
		struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp);

		mempool_free(fsp, si->scsi_pkt_pool);
	}
}

static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp)
{
	atomic_inc(&fsp->ref_cnt);
}

/**
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 * fc_fcp_pkt_destory() - release hold on scsi_pkt packet
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 * @seq:		exchange sequence
 * @fsp:	fcp packet struct
 *
 * Release hold on scsi_pkt packet set to keep scsi_pkt
 * till EM layer exch resource is not freed.
 * Context	: called from from EM layer.
 *		  no locking required
 */
static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp)
{
	fc_fcp_pkt_release(fsp);
}

/**
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 * fc_fcp_lock_pkt() - lock a packet and get a ref to it.
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 * @fsp:	fcp packet
 *
 * We should only return error if we return a command to scsi-ml before
 * getting a response. This can happen in cases where we send a abort, but
 * do not wait for the response and the abort and command can be passing
 * each other on the wire/network-layer.
 *
 * Note: this function locks the packet and gets a reference to allow
 * callers to call the completion function while the lock is held and
 * not have to worry about the packets refcount.
 *
 * TODO: Maybe we should just have callers grab/release the lock and
 * have a function that they call to verify the fsp and grab a ref if
 * needed.
 */
static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *fsp)
{
	spin_lock_bh(&fsp->scsi_pkt_lock);
	if (fsp->state & FC_SRB_COMPL) {
		spin_unlock_bh(&fsp->scsi_pkt_lock);
		return -EPERM;
	}

	fc_fcp_pkt_hold(fsp);
	return 0;
}

static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp)
{
	spin_unlock_bh(&fsp->scsi_pkt_lock);
	fc_fcp_pkt_release(fsp);
}

static void fc_fcp_timer_set(struct fc_fcp_pkt *fsp, unsigned long delay)
{
	if (!(fsp->state & FC_SRB_COMPL))
		mod_timer(&fsp->timer, jiffies + delay);
}

static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
{
	if (!fsp->seq_ptr)
		return -EINVAL;

	fsp->state |= FC_SRB_ABORT_PENDING;
	return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0);
}

/*
 * Retry command.
 * An abort isn't needed.
 */
static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp)
{
	if (fsp->seq_ptr) {
		fsp->lp->tt.exch_done(fsp->seq_ptr);
		fsp->seq_ptr = NULL;
	}

	fsp->state &= ~FC_SRB_ABORT_PENDING;
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	fsp->io_status = 0;
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	fsp->status_code = FC_ERROR;
	fc_fcp_complete_locked(fsp);
}

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/*
 * fc_fcp_ddp_setup - calls to LLD's ddp_setup to set up DDP
 * transfer for a read I/O indicated by the fc_fcp_pkt.
 * @fsp: ptr to the fc_fcp_pkt
 *
 * This is called in exch_seq_send() when we have a newly allocated
 * exchange with a valid exchange id to setup ddp.
 *
 * returns: none
 */
void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid)
{
	struct fc_lport *lp;

	if (!fsp)
		return;

	lp = fsp->lp;
	if ((fsp->req_flags & FC_SRB_READ) &&
	    (lp->lro_enabled) && (lp->tt.ddp_setup)) {
		if (lp->tt.ddp_setup(lp, xid, scsi_sglist(fsp->cmd),
				     scsi_sg_count(fsp->cmd)))
			fsp->xfer_ddp = xid;
	}
}

/*
 * fc_fcp_ddp_done - calls to LLD's ddp_done to release any
 * DDP related resources for this I/O if it is initialized
 * as a ddp transfer
 * @fsp: ptr to the fc_fcp_pkt
 *
 * returns: none
 */
static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp)
{
	struct fc_lport *lp;

	if (!fsp)
		return;

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	if (fsp->xfer_ddp == FC_XID_UNKNOWN)
		return;

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	lp = fsp->lp;
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	if (lp->tt.ddp_done) {
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		fsp->xfer_len = lp->tt.ddp_done(lp, fsp->xfer_ddp);
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		fsp->xfer_ddp = FC_XID_UNKNOWN;
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	}
}


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/*
 * Receive SCSI data from target.
 * Called after receiving solicited data.
 */
static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
{
	struct scsi_cmnd *sc = fsp->cmd;
	struct fc_lport *lp = fsp->lp;
	struct fcoe_dev_stats *stats;
	struct fc_frame_header *fh;
	size_t start_offset;
	size_t offset;
	u32 crc;
	u32 copy_len = 0;
	size_t len;
	void *buf;
	struct scatterlist *sg;
	size_t remaining;

	fh = fc_frame_header_get(fp);
	offset = ntohl(fh->fh_parm_offset);
	start_offset = offset;
	len = fr_len(fp) - sizeof(*fh);
	buf = fc_frame_payload_get(fp, 0);

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	/* if this I/O is ddped, update xfer len */
	fc_fcp_ddp_done(fsp);

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	if (offset + len > fsp->data_len) {
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		/* this should never happen */
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		if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
		    fc_frame_crc_check(fp))
			goto crc_err;
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		FC_FCP_DBG(fsp, "data received past end. len %zx offset %zx "
			   "data_len %x\n", len, offset, fsp->data_len);
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		fc_fcp_retry_cmd(fsp);
		return;
	}
	if (offset != fsp->xfer_len)
		fsp->state |= FC_SRB_DISCONTIG;

	crc = 0;
	if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
		crc = crc32(~0, (u8 *) fh, sizeof(*fh));

	sg = scsi_sglist(sc);
	remaining = len;

	while (remaining > 0 && sg) {
		size_t off;
		void *page_addr;
		size_t sg_bytes;

		if (offset >= sg->length) {
			offset -= sg->length;
			sg = sg_next(sg);
			continue;
		}
		sg_bytes = min(remaining, sg->length - offset);

		/*
		 * The scatterlist item may be bigger than PAGE_SIZE,
		 * but we are limited to mapping PAGE_SIZE at a time.
		 */
		off = offset + sg->offset;
		sg_bytes = min(sg_bytes, (size_t)
			       (PAGE_SIZE - (off & ~PAGE_MASK)));
		page_addr = kmap_atomic(sg_page(sg) + (off >> PAGE_SHIFT),
					KM_SOFTIRQ0);
		if (!page_addr)
			break;		/* XXX panic? */

		if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
			crc = crc32(crc, buf, sg_bytes);
		memcpy((char *)page_addr + (off & ~PAGE_MASK), buf,
		       sg_bytes);

		kunmap_atomic(page_addr, KM_SOFTIRQ0);
		buf += sg_bytes;
		offset += sg_bytes;
		remaining -= sg_bytes;
		copy_len += sg_bytes;
	}

	if (fr_flags(fp) & FCPHF_CRC_UNCHECKED) {
		buf = fc_frame_payload_get(fp, 0);
		if (len % 4) {
			crc = crc32(crc, buf + len, 4 - (len % 4));
			len += 4 - (len % 4);
		}

		if (~crc != le32_to_cpu(fr_crc(fp))) {
crc_err:
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			stats = fc_lport_get_stats(lp);
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			stats->ErrorFrames++;
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			/* FIXME - per cpu count, not total count! */
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			if (stats->InvalidCRCCount++ < 5)
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				printk(KERN_WARNING "libfc: CRC error on data "
				       "frame for port (%6x)\n",
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				       fc_host_port_id(lp->host));
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			/*
			 * Assume the frame is total garbage.
			 * We may have copied it over the good part
			 * of the buffer.
			 * If so, we need to retry the entire operation.
			 * Otherwise, ignore it.
			 */
			if (fsp->state & FC_SRB_DISCONTIG)
				fc_fcp_retry_cmd(fsp);
			return;
		}
	}

	if (fsp->xfer_contig_end == start_offset)
		fsp->xfer_contig_end += copy_len;
	fsp->xfer_len += copy_len;

	/*
	 * In the very rare event that this data arrived after the response
	 * and completes the transfer, call the completion handler.
	 */
	if (unlikely(fsp->state & FC_SRB_RCV_STATUS) &&
	    fsp->xfer_len == fsp->data_len - fsp->scsi_resid)
		fc_fcp_complete_locked(fsp);
}

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/**
 * fc_fcp_send_data() -  Send SCSI data to target.
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 * @fsp: ptr to fc_fcp_pkt
 * @sp: ptr to this sequence
 * @offset: starting offset for this data request
 * @seq_blen: the burst length for this data request
 *
 * Called after receiving a Transfer Ready data descriptor.
 * if LLD is capable of seq offload then send down seq_blen
 * size of data in single frame, otherwise send multiple FC
 * frames of max FC frame payload supported by target port.
 *
 * Returns : 0 for success.
 */
static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq,
			    size_t offset, size_t seq_blen)
{
	struct fc_exch *ep;
	struct scsi_cmnd *sc;
	struct scatterlist *sg;
	struct fc_frame *fp = NULL;
	struct fc_lport *lp = fsp->lp;
	size_t remaining;
	size_t t_blen;
	size_t tlen;
	size_t sg_bytes;
	size_t frame_offset, fh_parm_offset;
	int error;
	void *data = NULL;
	void *page_addr;
	int using_sg = lp->sg_supp;
	u32 f_ctl;

	WARN_ON(seq_blen <= 0);
	if (unlikely(offset + seq_blen > fsp->data_len)) {
		/* this should never happen */
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		FC_FCP_DBG(fsp, "xfer-ready past end. seq_blen %zx "
			   "offset %zx\n", seq_blen, offset);
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		fc_fcp_send_abort(fsp);
		return 0;
	} else if (offset != fsp->xfer_len) {
		/* Out of Order Data Request - no problem, but unexpected. */
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		FC_FCP_DBG(fsp, "xfer-ready non-contiguous. "
			   "seq_blen %zx offset %zx\n", seq_blen, offset);
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	}

	/*
	 * if LLD is capable of seq_offload then set transport
	 * burst length (t_blen) to seq_blen, otherwise set t_blen
	 * to max FC frame payload previously set in fsp->max_payload.
	 */
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	t_blen = fsp->max_payload;
	if (lp->seq_offload) {
		t_blen = min(seq_blen, (size_t)lp->lso_max);
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		FC_FCP_DBG(fsp, "fsp=%p:lso:blen=%zx lso_max=0x%x t_blen=%zx\n",
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			   fsp, seq_blen, lp->lso_max, t_blen);
	}

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	WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);
	if (t_blen > 512)
		t_blen &= ~(512 - 1);	/* round down to block size */
	WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);	/* won't go below 256 */
	sc = fsp->cmd;

	remaining = seq_blen;
	fh_parm_offset = frame_offset = offset;
	tlen = 0;
	seq = lp->tt.seq_start_next(seq);
	f_ctl = FC_FC_REL_OFF;
	WARN_ON(!seq);

	sg = scsi_sglist(sc);

	while (remaining > 0 && sg) {
		if (offset >= sg->length) {
			offset -= sg->length;
			sg = sg_next(sg);
			continue;
		}
		if (!fp) {
			tlen = min(t_blen, remaining);

			/*
			 * TODO.  Temporary workaround.	 fc_seq_send() can't
			 * handle odd lengths in non-linear skbs.
			 * This will be the final fragment only.
			 */
			if (tlen % 4)
				using_sg = 0;
			if (using_sg) {
				fp = _fc_frame_alloc(lp, 0);
				if (!fp)
					return -ENOMEM;
			} else {
				fp = fc_frame_alloc(lp, tlen);
				if (!fp)
					return -ENOMEM;

				data = (void *)(fr_hdr(fp)) +
					sizeof(struct fc_frame_header);
			}
			fh_parm_offset = frame_offset;
			fr_max_payload(fp) = fsp->max_payload;
		}
		sg_bytes = min(tlen, sg->length - offset);
		if (using_sg) {
			get_page(sg_page(sg));
			skb_fill_page_desc(fp_skb(fp),
					   skb_shinfo(fp_skb(fp))->nr_frags,
					   sg_page(sg), sg->offset + offset,
					   sg_bytes);
			fp_skb(fp)->data_len += sg_bytes;
			fr_len(fp) += sg_bytes;
			fp_skb(fp)->truesize += PAGE_SIZE;
		} else {
			size_t off = offset + sg->offset;

			/*
			 * The scatterlist item may be bigger than PAGE_SIZE,
			 * but we must not cross pages inside the kmap.
			 */
			sg_bytes = min(sg_bytes, (size_t) (PAGE_SIZE -
							   (off & ~PAGE_MASK)));
			page_addr = kmap_atomic(sg_page(sg) +
						(off >> PAGE_SHIFT),
						KM_SOFTIRQ0);
			memcpy(data, (char *)page_addr + (off & ~PAGE_MASK),
			       sg_bytes);
			kunmap_atomic(page_addr, KM_SOFTIRQ0);
			data += sg_bytes;
		}
		offset += sg_bytes;
		frame_offset += sg_bytes;
		tlen -= sg_bytes;
		remaining -= sg_bytes;

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		if ((skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN) &&
		    (tlen))
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			continue;

		/*
		 * Send sequence with transfer sequence initiative in case
		 * this is last FCP frame of the sequence.
		 */
		if (remaining == 0)
			f_ctl |= FC_FC_SEQ_INIT | FC_FC_END_SEQ;

		ep = fc_seq_exch(seq);
		fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
			       FC_TYPE_FCP, f_ctl, fh_parm_offset);

		/*
		 * send fragment using for a sequence.
		 */
		error = lp->tt.seq_send(lp, seq, fp);
		if (error) {
			WARN_ON(1);		/* send error should be rare */
			fc_fcp_retry_cmd(fsp);
			return 0;
		}
		fp = NULL;
	}
	fsp->xfer_len += seq_blen;	/* premature count? */
	return 0;
}

static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
{
	int ba_done = 1;
	struct fc_ba_rjt *brp;
	struct fc_frame_header *fh;

	fh = fc_frame_header_get(fp);
	switch (fh->fh_r_ctl) {
	case FC_RCTL_BA_ACC:
		break;
	case FC_RCTL_BA_RJT:
		brp = fc_frame_payload_get(fp, sizeof(*brp));
		if (brp && brp->br_reason == FC_BA_RJT_LOG_ERR)
			break;
		/* fall thru */
	default:
		/*
		 * we will let the command timeout
		 * and scsi-ml recover in this case,
		 * therefore cleared the ba_done flag.
		 */
		ba_done = 0;
	}

	if (ba_done) {
		fsp->state |= FC_SRB_ABORTED;
		fsp->state &= ~FC_SRB_ABORT_PENDING;

		if (fsp->wait_for_comp)
			complete(&fsp->tm_done);
		else
			fc_fcp_complete_locked(fsp);
	}
}

636 637
/**
 * fc_fcp_reduce_can_queue() - drop can_queue
638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661
 * @lp: lport to drop queueing for
 *
 * If we are getting memory allocation failures, then we may
 * be trying to execute too many commands. We let the running
 * commands complete or timeout, then try again with a reduced
 * can_queue. Eventually we will hit the point where we run
 * on all reserved structs.
 */
static void fc_fcp_reduce_can_queue(struct fc_lport *lp)
{
	struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
	unsigned long flags;
	int can_queue;

	spin_lock_irqsave(lp->host->host_lock, flags);
	if (si->throttled)
		goto done;
	si->throttled = 1;

	can_queue = lp->host->can_queue;
	can_queue >>= 1;
	if (!can_queue)
		can_queue = 1;
	lp->host->can_queue = can_queue;
662
	shost_printk(KERN_ERR, lp->host, "libfc: Could not allocate frame.\n"
663 664 665 666 667
		     "Reducing can_queue to %d.\n", can_queue);
done:
	spin_unlock_irqrestore(lp->host->host_lock, flags);
}

668 669 670 671 672
/**
 * fc_fcp_recv() - Reveive FCP frames
 * @seq: The sequence the frame is on
 * @fp: The FC frame
 * @arg: The related FCP packet
673 674 675 676 677 678 679 680
 *
 * Return   : None
 * Context  : called from Soft IRQ context
 *	      can not called holding list lock
 */
static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg)
{
	struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
681
	struct fc_lport *lport = fsp->lp;
682 683 684 685 686 687 688 689 690 691 692
	struct fc_frame_header *fh;
	struct fcp_txrdy *dd;
	u8 r_ctl;
	int rc = 0;

	if (IS_ERR(fp))
		goto errout;

	fh = fc_frame_header_get(fp);
	r_ctl = fh->fh_r_ctl;

693
	if (!(lport->state & LPORT_ST_READY))
694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735
		goto out;
	if (fc_fcp_lock_pkt(fsp))
		goto out;
	fsp->last_pkt_time = jiffies;

	if (fh->fh_type == FC_TYPE_BLS) {
		fc_fcp_abts_resp(fsp, fp);
		goto unlock;
	}

	if (fsp->state & (FC_SRB_ABORTED | FC_SRB_ABORT_PENDING))
		goto unlock;

	if (r_ctl == FC_RCTL_DD_DATA_DESC) {
		/*
		 * received XFER RDY from the target
		 * need to send data to the target
		 */
		WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
		dd = fc_frame_payload_get(fp, sizeof(*dd));
		WARN_ON(!dd);

		rc = fc_fcp_send_data(fsp, seq,
				      (size_t) ntohl(dd->ft_data_ro),
				      (size_t) ntohl(dd->ft_burst_len));
		if (!rc)
			seq->rec_data = fsp->xfer_len;
		else if (rc == -ENOMEM)
			fsp->state |= FC_SRB_NOMEM;
	} else if (r_ctl == FC_RCTL_DD_SOL_DATA) {
		/*
		 * received a DATA frame
		 * next we will copy the data to the system buffer
		 */
		WARN_ON(fr_len(fp) < sizeof(*fh));	/* len may be 0 */
		fc_fcp_recv_data(fsp, fp);
		seq->rec_data = fsp->xfer_contig_end;
	} else if (r_ctl == FC_RCTL_DD_CMD_STATUS) {
		WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);

		fc_fcp_resp(fsp, fp);
	} else {
736
		FC_FCP_DBG(fsp, "unexpected frame.  r_ctl %x\n", r_ctl);
737 738 739 740 741 742 743 744 745
	}
unlock:
	fc_fcp_unlock_pkt(fsp);
out:
	fc_frame_free(fp);
errout:
	if (IS_ERR(fp))
		fc_fcp_error(fsp, fp);
	else if (rc == -ENOMEM)
746
		fc_fcp_reduce_can_queue(lport);
747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771
}

static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
{
	struct fc_frame_header *fh;
	struct fcp_resp *fc_rp;
	struct fcp_resp_ext *rp_ex;
	struct fcp_resp_rsp_info *fc_rp_info;
	u32 plen;
	u32 expected_len;
	u32 respl = 0;
	u32 snsl = 0;
	u8 flags = 0;

	plen = fr_len(fp);
	fh = (struct fc_frame_header *)fr_hdr(fp);
	if (unlikely(plen < sizeof(*fh) + sizeof(*fc_rp)))
		goto len_err;
	plen -= sizeof(*fh);
	fc_rp = (struct fcp_resp *)(fh + 1);
	fsp->cdb_status = fc_rp->fr_status;
	flags = fc_rp->fr_flags;
	fsp->scsi_comp_flags = flags;
	expected_len = fsp->data_len;

772 773 774
	/* if ddp, update xfer len */
	fc_fcp_ddp_done(fsp);

775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844
	if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) {
		rp_ex = (void *)(fc_rp + 1);
		if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) {
			if (plen < sizeof(*fc_rp) + sizeof(*rp_ex))
				goto len_err;
			fc_rp_info = (struct fcp_resp_rsp_info *)(rp_ex + 1);
			if (flags & FCP_RSP_LEN_VAL) {
				respl = ntohl(rp_ex->fr_rsp_len);
				if (respl != sizeof(*fc_rp_info))
					goto len_err;
				if (fsp->wait_for_comp) {
					/* Abuse cdb_status for rsp code */
					fsp->cdb_status = fc_rp_info->rsp_code;
					complete(&fsp->tm_done);
					/*
					 * tmfs will not have any scsi cmd so
					 * exit here
					 */
					return;
				} else
					goto err;
			}
			if (flags & FCP_SNS_LEN_VAL) {
				snsl = ntohl(rp_ex->fr_sns_len);
				if (snsl > SCSI_SENSE_BUFFERSIZE)
					snsl = SCSI_SENSE_BUFFERSIZE;
				memcpy(fsp->cmd->sense_buffer,
				       (char *)fc_rp_info + respl, snsl);
			}
		}
		if (flags & (FCP_RESID_UNDER | FCP_RESID_OVER)) {
			if (plen < sizeof(*fc_rp) + sizeof(rp_ex->fr_resid))
				goto len_err;
			if (flags & FCP_RESID_UNDER) {
				fsp->scsi_resid = ntohl(rp_ex->fr_resid);
				/*
				 * The cmnd->underflow is the minimum number of
				 * bytes that must be transfered for this
				 * command.  Provided a sense condition is not
				 * present, make sure the actual amount
				 * transferred is at least the underflow value
				 * or fail.
				 */
				if (!(flags & FCP_SNS_LEN_VAL) &&
				    (fc_rp->fr_status == 0) &&
				    (scsi_bufflen(fsp->cmd) -
				     fsp->scsi_resid) < fsp->cmd->underflow)
					goto err;
				expected_len -= fsp->scsi_resid;
			} else {
				fsp->status_code = FC_ERROR;
			}
		}
	}
	fsp->state |= FC_SRB_RCV_STATUS;

	/*
	 * Check for missing or extra data frames.
	 */
	if (unlikely(fsp->xfer_len != expected_len)) {
		if (fsp->xfer_len < expected_len) {
			/*
			 * Some data may be queued locally,
			 * Wait a at least one jiffy to see if it is delivered.
			 * If this expires without data, we may do SRR.
			 */
			fc_fcp_timer_set(fsp, 2);
			return;
		}
		fsp->status_code = FC_DATA_OVRRUN;
845 846 847 848
		FC_FCP_DBG(fsp, "tgt %6x xfer len %zx greater than expected, "
			   "len %x, data len %x\n",
			   fsp->rport->port_id,
			   fsp->xfer_len, expected_len, fsp->data_len);
849 850 851 852 853
	}
	fc_fcp_complete_locked(fsp);
	return;

len_err:
854 855
	FC_FCP_DBG(fsp, "short FCP response. flags 0x%x len %u respl %u "
		   "snsl %u\n", flags, fr_len(fp), respl, snsl);
856 857 858 859 860 861
err:
	fsp->status_code = FC_ERROR;
	fc_fcp_complete_locked(fsp);
}

/**
862
 * fc_fcp_complete_locked() - complete processing of a fcp packet
863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889
 * @fsp:	fcp packet
 *
 * This function may sleep if a timer is pending. The packet lock must be
 * held, and the host lock must not be held.
 */
static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
{
	struct fc_lport *lp = fsp->lp;
	struct fc_seq *seq;
	struct fc_exch *ep;
	u32 f_ctl;

	if (fsp->state & FC_SRB_ABORT_PENDING)
		return;

	if (fsp->state & FC_SRB_ABORTED) {
		if (!fsp->status_code)
			fsp->status_code = FC_CMD_ABORTED;
	} else {
		/*
		 * Test for transport underrun, independent of response
		 * underrun status.
		 */
		if (fsp->xfer_len < fsp->data_len && !fsp->io_status &&
		    (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
		     fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
			fsp->status_code = FC_DATA_UNDRUN;
M
Martin K. Petersen 已提交
890
			fsp->io_status = 0;
891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929
		}
	}

	seq = fsp->seq_ptr;
	if (seq) {
		fsp->seq_ptr = NULL;
		if (unlikely(fsp->scsi_comp_flags & FCP_CONF_REQ)) {
			struct fc_frame *conf_frame;
			struct fc_seq *csp;

			csp = lp->tt.seq_start_next(seq);
			conf_frame = fc_frame_alloc(fsp->lp, 0);
			if (conf_frame) {
				f_ctl = FC_FC_SEQ_INIT;
				f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
				ep = fc_seq_exch(seq);
				fc_fill_fc_hdr(conf_frame, FC_RCTL_DD_SOL_CTL,
					       ep->did, ep->sid,
					       FC_TYPE_FCP, f_ctl, 0);
				lp->tt.seq_send(lp, csp, conf_frame);
			}
		}
		lp->tt.exch_done(seq);
	}
	fc_io_compl(fsp);
}

static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error)
{
	struct fc_lport *lp = fsp->lp;

	if (fsp->seq_ptr) {
		lp->tt.exch_done(fsp->seq_ptr);
		fsp->seq_ptr = NULL;
	}
	fsp->status_code = error;
}

/**
930
 * fc_fcp_cleanup_each_cmd() - Cleanup active commads
931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981
 * @lp:		logical port
 * @id:		target id
 * @lun:	lun
 * @error:	fsp status code
 *
 * If lun or id is -1, they are ignored.
 */
static void fc_fcp_cleanup_each_cmd(struct fc_lport *lp, unsigned int id,
				    unsigned int lun, int error)
{
	struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
	struct fc_fcp_pkt *fsp;
	struct scsi_cmnd *sc_cmd;
	unsigned long flags;

	spin_lock_irqsave(lp->host->host_lock, flags);
restart:
	list_for_each_entry(fsp, &si->scsi_pkt_queue, list) {
		sc_cmd = fsp->cmd;
		if (id != -1 && scmd_id(sc_cmd) != id)
			continue;

		if (lun != -1 && sc_cmd->device->lun != lun)
			continue;

		fc_fcp_pkt_hold(fsp);
		spin_unlock_irqrestore(lp->host->host_lock, flags);

		if (!fc_fcp_lock_pkt(fsp)) {
			fc_fcp_cleanup_cmd(fsp, error);
			fc_io_compl(fsp);
			fc_fcp_unlock_pkt(fsp);
		}

		fc_fcp_pkt_release(fsp);
		spin_lock_irqsave(lp->host->host_lock, flags);
		/*
		 * while we dropped the lock multiple pkts could
		 * have been released, so we have to start over.
		 */
		goto restart;
	}
	spin_unlock_irqrestore(lp->host->host_lock, flags);
}

static void fc_fcp_abort_io(struct fc_lport *lp)
{
	fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_HRD_ERROR);
}

/**
982
 * fc_fcp_pkt_send() - send a fcp packet to the lower level.
983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036
 * @lp:		fc lport
 * @fsp:	fc packet.
 *
 * This is called by upper layer protocol.
 * Return   : zero for success and -1 for failure
 * Context  : called from queuecommand which can be called from process
 *	      or scsi soft irq.
 * Locks    : called with the host lock and irqs disabled.
 */
static int fc_fcp_pkt_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
{
	struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
	int rc;

	fsp->cmd->SCp.ptr = (char *)fsp;
	fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
	fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;

	int_to_scsilun(fsp->cmd->device->lun,
		       (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
	memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len);
	list_add_tail(&fsp->list, &si->scsi_pkt_queue);

	spin_unlock_irq(lp->host->host_lock);
	rc = lp->tt.fcp_cmd_send(lp, fsp, fc_fcp_recv);
	spin_lock_irq(lp->host->host_lock);
	if (rc)
		list_del(&fsp->list);

	return rc;
}

static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
			   void (*resp)(struct fc_seq *,
					struct fc_frame *fp,
					void *arg))
{
	struct fc_frame *fp;
	struct fc_seq *seq;
	struct fc_rport *rport;
	struct fc_rport_libfc_priv *rp;
	const size_t len = sizeof(fsp->cdb_cmd);
	int rc = 0;

	if (fc_fcp_lock_pkt(fsp))
		return 0;

	fp = fc_frame_alloc(lp, sizeof(fsp->cdb_cmd));
	if (!fp) {
		rc = -1;
		goto unlock;
	}

	memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len);
1037
	fr_fsp(fp) = fsp;
1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073
	rport = fsp->rport;
	fsp->max_payload = rport->maxframe_size;
	rp = rport->dd_data;

	fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id,
		       fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
		       FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);

	seq = lp->tt.exch_seq_send(lp, fp, resp, fc_fcp_pkt_destroy, fsp, 0);
	if (!seq) {
		rc = -1;
		goto unlock;
	}
	fsp->last_pkt_time = jiffies;
	fsp->seq_ptr = seq;
	fc_fcp_pkt_hold(fsp);	/* hold for fc_fcp_pkt_destroy */

	setup_timer(&fsp->timer, fc_fcp_timeout, (unsigned long)fsp);
	fc_fcp_timer_set(fsp,
			 (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED) ?
			 FC_SCSI_REC_TOV : FC_SCSI_ER_TIMEOUT);
unlock:
	fc_fcp_unlock_pkt(fsp);
	return rc;
}

/*
 * transport error handler
 */
static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
{
	int error = PTR_ERR(fp);

	if (fc_fcp_lock_pkt(fsp))
		return;

1074
	if (error == -FC_EX_CLOSED) {
1075 1076 1077
		fc_fcp_retry_cmd(fsp);
		goto unlock;
	}
1078

1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093
	/*
	 * clear abort pending, because the lower layer
	 * decided to force completion.
	 */
	fsp->state &= ~FC_SRB_ABORT_PENDING;
	fsp->status_code = FC_CMD_PLOGO;
	fc_fcp_complete_locked(fsp);
unlock:
	fc_fcp_unlock_pkt(fsp);
}

/*
 * Scsi abort handler- calls to send an abort
 * and then wait for abort completion
 */
1094
static int fc_fcp_pkt_abort(struct fc_fcp_pkt *fsp)
1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109
{
	int rc = FAILED;

	if (fc_fcp_send_abort(fsp))
		return FAILED;

	init_completion(&fsp->tm_done);
	fsp->wait_for_comp = 1;

	spin_unlock_bh(&fsp->scsi_pkt_lock);
	rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
	spin_lock_bh(&fsp->scsi_pkt_lock);
	fsp->wait_for_comp = 0;

	if (!rc) {
1110
		FC_FCP_DBG(fsp, "target abort cmd  failed\n");
1111 1112
		rc = FAILED;
	} else if (fsp->state & FC_SRB_ABORTED) {
1113
		FC_FCP_DBG(fsp, "target abort cmd  passed\n");
1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177
		rc = SUCCESS;
		fc_fcp_complete_locked(fsp);
	}

	return rc;
}

/*
 * Retry LUN reset after resource allocation failed.
 */
static void fc_lun_reset_send(unsigned long data)
{
	struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
	struct fc_lport *lp = fsp->lp;
	if (lp->tt.fcp_cmd_send(lp, fsp, fc_tm_done)) {
		if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
			return;
		if (fc_fcp_lock_pkt(fsp))
			return;
		setup_timer(&fsp->timer, fc_lun_reset_send, (unsigned long)fsp);
		fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
		fc_fcp_unlock_pkt(fsp);
	}
}

/*
 * Scsi device reset handler- send a LUN RESET to the device
 * and wait for reset reply
 */
static int fc_lun_reset(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
			unsigned int id, unsigned int lun)
{
	int rc;

	fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
	fsp->cdb_cmd.fc_tm_flags = FCP_TMF_LUN_RESET;
	int_to_scsilun(lun, (struct scsi_lun *)fsp->cdb_cmd.fc_lun);

	fsp->wait_for_comp = 1;
	init_completion(&fsp->tm_done);

	fc_lun_reset_send((unsigned long)fsp);

	/*
	 * wait for completion of reset
	 * after that make sure all commands are terminated
	 */
	rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);

	spin_lock_bh(&fsp->scsi_pkt_lock);
	fsp->state |= FC_SRB_COMPL;
	spin_unlock_bh(&fsp->scsi_pkt_lock);

	del_timer_sync(&fsp->timer);

	spin_lock_bh(&fsp->scsi_pkt_lock);
	if (fsp->seq_ptr) {
		lp->tt.exch_done(fsp->seq_ptr);
		fsp->seq_ptr = NULL;
	}
	fsp->wait_for_comp = 0;
	spin_unlock_bh(&fsp->scsi_pkt_lock);

	if (!rc) {
1178
		FC_SCSI_DBG(lp, "lun reset failed\n");
1179 1180 1181 1182 1183 1184 1185
		return FAILED;
	}

	/* cdb_status holds the tmf's rsp code */
	if (fsp->cdb_status != FCP_TMF_CMPL)
		return FAILED;

1186
	FC_SCSI_DBG(lp, "lun reset to lun %u completed\n", lun);
1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294
	fc_fcp_cleanup_each_cmd(lp, id, lun, FC_CMD_ABORTED);
	return SUCCESS;
}

/*
 * Task Managment response handler
 */
static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg)
{
	struct fc_fcp_pkt *fsp = arg;
	struct fc_frame_header *fh;

	if (IS_ERR(fp)) {
		/*
		 * If there is an error just let it timeout or wait
		 * for TMF to be aborted if it timedout.
		 *
		 * scsi-eh will escalate for when either happens.
		 */
		return;
	}

	if (fc_fcp_lock_pkt(fsp))
		return;

	/*
	 * raced with eh timeout handler.
	 */
	if (!fsp->seq_ptr || !fsp->wait_for_comp) {
		spin_unlock_bh(&fsp->scsi_pkt_lock);
		return;
	}

	fh = fc_frame_header_get(fp);
	if (fh->fh_type != FC_TYPE_BLS)
		fc_fcp_resp(fsp, fp);
	fsp->seq_ptr = NULL;
	fsp->lp->tt.exch_done(seq);
	fc_frame_free(fp);
	fc_fcp_unlock_pkt(fsp);
}

static void fc_fcp_cleanup(struct fc_lport *lp)
{
	fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_ERROR);
}

/*
 * fc_fcp_timeout: called by OS timer function.
 *
 * The timer has been inactivated and must be reactivated if desired
 * using fc_fcp_timer_set().
 *
 * Algorithm:
 *
 * If REC is supported, just issue it, and return.  The REC exchange will
 * complete or time out, and recovery can continue at that point.
 *
 * Otherwise, if the response has been received without all the data,
 * it has been ER_TIMEOUT since the response was received.
 *
 * If the response has not been received,
 * we see if data was received recently.  If it has been, we continue waiting,
 * otherwise, we abort the command.
 */
static void fc_fcp_timeout(unsigned long data)
{
	struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
	struct fc_rport *rport = fsp->rport;
	struct fc_rport_libfc_priv *rp = rport->dd_data;

	if (fc_fcp_lock_pkt(fsp))
		return;

	if (fsp->cdb_cmd.fc_tm_flags)
		goto unlock;

	fsp->state |= FC_SRB_FCP_PROCESSING_TMO;

	if (rp->flags & FC_RP_FLAGS_REC_SUPPORTED)
		fc_fcp_rec(fsp);
	else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2),
			       jiffies))
		fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
	else if (fsp->state & FC_SRB_RCV_STATUS)
		fc_fcp_complete_locked(fsp);
	else
		fc_timeout_error(fsp);
	fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO;
unlock:
	fc_fcp_unlock_pkt(fsp);
}

/*
 * Send a REC ELS request
 */
static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
{
	struct fc_lport *lp;
	struct fc_frame *fp;
	struct fc_rport *rport;
	struct fc_rport_libfc_priv *rp;

	lp = fsp->lp;
	rport = fsp->rport;
	rp = rport->dd_data;
	if (!fsp->seq_ptr || rp->rp_state != RPORT_ST_READY) {
		fsp->status_code = FC_HRD_ERROR;
M
Martin K. Petersen 已提交
1295
		fsp->io_status = 0;
1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306
		fc_fcp_complete_locked(fsp);
		return;
	}
	fp = fc_frame_alloc(lp, sizeof(struct fc_els_rec));
	if (!fp)
		goto retry;

	fr_seq(fp) = fsp->seq_ptr;
	fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, rport->port_id,
		       fc_host_port_id(rp->local_port->host), FC_TYPE_ELS,
		       FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1307
	if (lp->tt.elsct_send(lp, rport->port_id, fp, ELS_REC, fc_fcp_rec_resp,
1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351
			      fsp, jiffies_to_msecs(FC_SCSI_REC_TOV))) {
		fc_fcp_pkt_hold(fsp);		/* hold while REC outstanding */
		return;
	}
retry:
	if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
		fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
	else
		fc_timeout_error(fsp);
}

/*
 * Receive handler for REC ELS frame
 * if it is a reject then let the scsi layer to handle
 * the timeout. if it is a LS_ACC then if the io was not completed
 * then set the timeout and return otherwise complete the exchange
 * and tell the scsi layer to restart the I/O.
 */
static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
{
	struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
	struct fc_els_rec_acc *recp;
	struct fc_els_ls_rjt *rjt;
	u32 e_stat;
	u8 opcode;
	u32 offset;
	enum dma_data_direction data_dir;
	enum fc_rctl r_ctl;
	struct fc_rport_libfc_priv *rp;

	if (IS_ERR(fp)) {
		fc_fcp_rec_error(fsp, fp);
		return;
	}

	if (fc_fcp_lock_pkt(fsp))
		goto out;

	fsp->recov_retry = 0;
	opcode = fc_frame_payload_op(fp);
	if (opcode == ELS_LS_RJT) {
		rjt = fc_frame_payload_get(fp, sizeof(*rjt));
		switch (rjt->er_reason) {
		default:
1352 1353 1354 1355
			FC_FCP_DBG(fsp, "device %x unexpected REC reject "
				   "reason %d expl %d\n",
				   fsp->rport->port_id, rjt->er_reason,
				   rjt->er_explan);
1356 1357
			/* fall through */
		case ELS_RJT_UNSUP:
1358
			FC_FCP_DBG(fsp, "device does not support REC\n");
1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477
			rp = fsp->rport->dd_data;
			/*
			 * if we do not spport RECs or got some bogus
			 * reason then resetup timer so we check for
			 * making progress.
			 */
			rp->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
			fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
			break;
		case ELS_RJT_LOGIC:
		case ELS_RJT_UNAB:
			/*
			 * If no data transfer, the command frame got dropped
			 * so we just retry.  If data was transferred, we
			 * lost the response but the target has no record,
			 * so we abort and retry.
			 */
			if (rjt->er_explan == ELS_EXPL_OXID_RXID &&
			    fsp->xfer_len == 0) {
				fc_fcp_retry_cmd(fsp);
				break;
			}
			fc_timeout_error(fsp);
			break;
		}
	} else if (opcode == ELS_LS_ACC) {
		if (fsp->state & FC_SRB_ABORTED)
			goto unlock_out;

		data_dir = fsp->cmd->sc_data_direction;
		recp = fc_frame_payload_get(fp, sizeof(*recp));
		offset = ntohl(recp->reca_fc4value);
		e_stat = ntohl(recp->reca_e_stat);

		if (e_stat & ESB_ST_COMPLETE) {

			/*
			 * The exchange is complete.
			 *
			 * For output, we must've lost the response.
			 * For input, all data must've been sent.
			 * We lost may have lost the response
			 * (and a confirmation was requested) and maybe
			 * some data.
			 *
			 * If all data received, send SRR
			 * asking for response.	 If partial data received,
			 * or gaps, SRR requests data at start of gap.
			 * Recovery via SRR relies on in-order-delivery.
			 */
			if (data_dir == DMA_TO_DEVICE) {
				r_ctl = FC_RCTL_DD_CMD_STATUS;
			} else if (fsp->xfer_contig_end == offset) {
				r_ctl = FC_RCTL_DD_CMD_STATUS;
			} else {
				offset = fsp->xfer_contig_end;
				r_ctl = FC_RCTL_DD_SOL_DATA;
			}
			fc_fcp_srr(fsp, r_ctl, offset);
		} else if (e_stat & ESB_ST_SEQ_INIT) {

			/*
			 * The remote port has the initiative, so just
			 * keep waiting for it to complete.
			 */
			fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
		} else {

			/*
			 * The exchange is incomplete, we have seq. initiative.
			 * Lost response with requested confirmation,
			 * lost confirmation, lost transfer ready or
			 * lost write data.
			 *
			 * For output, if not all data was received, ask
			 * for transfer ready to be repeated.
			 *
			 * If we received or sent all the data, send SRR to
			 * request response.
			 *
			 * If we lost a response, we may have lost some read
			 * data as well.
			 */
			r_ctl = FC_RCTL_DD_SOL_DATA;
			if (data_dir == DMA_TO_DEVICE) {
				r_ctl = FC_RCTL_DD_CMD_STATUS;
				if (offset < fsp->data_len)
					r_ctl = FC_RCTL_DD_DATA_DESC;
			} else if (offset == fsp->xfer_contig_end) {
				r_ctl = FC_RCTL_DD_CMD_STATUS;
			} else if (fsp->xfer_contig_end < offset) {
				offset = fsp->xfer_contig_end;
			}
			fc_fcp_srr(fsp, r_ctl, offset);
		}
	}
unlock_out:
	fc_fcp_unlock_pkt(fsp);
out:
	fc_fcp_pkt_release(fsp);	/* drop hold for outstanding REC */
	fc_frame_free(fp);
}

/*
 * Handle error response or timeout for REC exchange.
 */
static void fc_fcp_rec_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
{
	int error = PTR_ERR(fp);

	if (fc_fcp_lock_pkt(fsp))
		goto out;

	switch (error) {
	case -FC_EX_CLOSED:
		fc_fcp_retry_cmd(fsp);
		break;

	default:
1478 1479
		FC_FCP_DBG(fsp, "REC %p fid %x error unexpected error %d\n",
			   fsp, fsp->rport->port_id, error);
1480 1481 1482 1483 1484 1485 1486 1487
		fsp->status_code = FC_CMD_PLOGO;
		/* fall through */

	case -FC_EX_TIMEOUT:
		/*
		 * Assume REC or LS_ACC was lost.
		 * The exchange manager will have aborted REC, so retry.
		 */
1488 1489 1490
		FC_FCP_DBG(fsp, "REC fid %x error error %d retry %d/%d\n",
			   fsp->rport->port_id, error, fsp->recov_retry,
			   FC_MAX_RECOV_RETRY);
1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558
		if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
			fc_fcp_rec(fsp);
		else
			fc_timeout_error(fsp);
		break;
	}
	fc_fcp_unlock_pkt(fsp);
out:
	fc_fcp_pkt_release(fsp);	/* drop hold for outstanding REC */
}

/*
 * Time out error routine:
 * abort's the I/O close the exchange and
 * send completion notification to scsi layer
 */
static void fc_timeout_error(struct fc_fcp_pkt *fsp)
{
	fsp->status_code = FC_CMD_TIME_OUT;
	fsp->cdb_status = 0;
	fsp->io_status = 0;
	/*
	 * if this fails then we let the scsi command timer fire and
	 * scsi-ml escalate.
	 */
	fc_fcp_send_abort(fsp);
}

/*
 * Sequence retransmission request.
 * This is called after receiving status but insufficient data, or
 * when expecting status but the request has timed out.
 */
static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
{
	struct fc_lport *lp = fsp->lp;
	struct fc_rport *rport;
	struct fc_rport_libfc_priv *rp;
	struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
	struct fc_seq *seq;
	struct fcp_srr *srr;
	struct fc_frame *fp;
	u8 cdb_op;

	rport = fsp->rport;
	rp = rport->dd_data;
	cdb_op = fsp->cdb_cmd.fc_cdb[0];

	if (!(rp->flags & FC_RP_FLAGS_RETRY) || rp->rp_state != RPORT_ST_READY)
		goto retry;			/* shouldn't happen */
	fp = fc_frame_alloc(lp, sizeof(*srr));
	if (!fp)
		goto retry;

	srr = fc_frame_payload_get(fp, sizeof(*srr));
	memset(srr, 0, sizeof(*srr));
	srr->srr_op = ELS_SRR;
	srr->srr_ox_id = htons(ep->oxid);
	srr->srr_rx_id = htons(ep->rxid);
	srr->srr_r_ctl = r_ctl;
	srr->srr_rel_off = htonl(offset);

	fc_fill_fc_hdr(fp, FC_RCTL_ELS4_REQ, rport->port_id,
		       fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
		       FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);

	seq = lp->tt.exch_seq_send(lp, fp, fc_fcp_srr_resp, NULL,
				   fsp, jiffies_to_msecs(FC_SCSI_REC_TOV));
1559
	if (!seq)
1560
		goto retry;
1561

1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645
	fsp->recov_seq = seq;
	fsp->xfer_len = offset;
	fsp->xfer_contig_end = offset;
	fsp->state &= ~FC_SRB_RCV_STATUS;
	fc_fcp_pkt_hold(fsp);		/* hold for outstanding SRR */
	return;
retry:
	fc_fcp_retry_cmd(fsp);
}

/*
 * Handle response from SRR.
 */
static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
{
	struct fc_fcp_pkt *fsp = arg;
	struct fc_frame_header *fh;

	if (IS_ERR(fp)) {
		fc_fcp_srr_error(fsp, fp);
		return;
	}

	if (fc_fcp_lock_pkt(fsp))
		goto out;

	fh = fc_frame_header_get(fp);
	/*
	 * BUG? fc_fcp_srr_error calls exch_done which would release
	 * the ep. But if fc_fcp_srr_error had got -FC_EX_TIMEOUT,
	 * then fc_exch_timeout would be sending an abort. The exch_done
	 * call by fc_fcp_srr_error would prevent fc_exch.c from seeing
	 * an abort response though.
	 */
	if (fh->fh_type == FC_TYPE_BLS) {
		fc_fcp_unlock_pkt(fsp);
		return;
	}

	fsp->recov_seq = NULL;
	switch (fc_frame_payload_op(fp)) {
	case ELS_LS_ACC:
		fsp->recov_retry = 0;
		fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
		break;
	case ELS_LS_RJT:
	default:
		fc_timeout_error(fsp);
		break;
	}
	fc_fcp_unlock_pkt(fsp);
	fsp->lp->tt.exch_done(seq);
out:
	fc_frame_free(fp);
	fc_fcp_pkt_release(fsp);	/* drop hold for outstanding SRR */
}

static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
{
	if (fc_fcp_lock_pkt(fsp))
		goto out;
	fsp->lp->tt.exch_done(fsp->recov_seq);
	fsp->recov_seq = NULL;
	switch (PTR_ERR(fp)) {
	case -FC_EX_TIMEOUT:
		if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
			fc_fcp_rec(fsp);
		else
			fc_timeout_error(fsp);
		break;
	case -FC_EX_CLOSED:			/* e.g., link failure */
		/* fall through */
	default:
		fc_fcp_retry_cmd(fsp);
		break;
	}
	fc_fcp_unlock_pkt(fsp);
out:
	fc_fcp_pkt_release(fsp);	/* drop hold for outstanding SRR */
}

static inline int fc_fcp_lport_queue_ready(struct fc_lport *lp)
{
	/* lock ? */
1646
	return (lp->state == LPORT_ST_READY) && lp->link_up && !lp->qfull;
1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704
}

/**
 * fc_queuecommand - The queuecommand function of the scsi template
 * @cmd:	struct scsi_cmnd to be executed
 * @done:	Callback function to be called when cmd is completed
 *
 * this is the i/o strategy routine, called by the scsi layer
 * this routine is called with holding the host_lock.
 */
int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *))
{
	struct fc_lport *lp;
	struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
	struct fc_fcp_pkt *fsp;
	struct fc_rport_libfc_priv *rp;
	int rval;
	int rc = 0;
	struct fcoe_dev_stats *stats;

	lp = shost_priv(sc_cmd->device->host);

	rval = fc_remote_port_chkready(rport);
	if (rval) {
		sc_cmd->result = rval;
		done(sc_cmd);
		goto out;
	}

	if (!*(struct fc_remote_port **)rport->dd_data) {
		/*
		 * rport is transitioning from blocked/deleted to
		 * online
		 */
		sc_cmd->result = DID_IMM_RETRY << 16;
		done(sc_cmd);
		goto out;
	}

	rp = rport->dd_data;

	if (!fc_fcp_lport_queue_ready(lp)) {
		rc = SCSI_MLQUEUE_HOST_BUSY;
		goto out;
	}

	fsp = fc_fcp_pkt_alloc(lp, GFP_ATOMIC);
	if (fsp == NULL) {
		rc = SCSI_MLQUEUE_HOST_BUSY;
		goto out;
	}

	/*
	 * build the libfc request pkt
	 */
	fsp->cmd = sc_cmd;	/* save the cmd */
	fsp->lp = lp;		/* save the softc ptr */
	fsp->rport = rport;	/* set the remote port ptr */
Y
Yi Zou 已提交
1705
	fsp->xfer_ddp = FC_XID_UNKNOWN;
1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716
	sc_cmd->scsi_done = done;

	/*
	 * set up the transfer length
	 */
	fsp->data_len = scsi_bufflen(sc_cmd);
	fsp->xfer_len = 0;

	/*
	 * setup the data direction
	 */
1717
	stats = fc_lport_get_stats(lp);
1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752
	if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
		fsp->req_flags = FC_SRB_READ;
		stats->InputRequests++;
		stats->InputMegabytes = fsp->data_len;
	} else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
		fsp->req_flags = FC_SRB_WRITE;
		stats->OutputRequests++;
		stats->OutputMegabytes = fsp->data_len;
	} else {
		fsp->req_flags = 0;
		stats->ControlRequests++;
	}

	fsp->tgt_flags = rp->flags;

	init_timer(&fsp->timer);
	fsp->timer.data = (unsigned long)fsp;

	/*
	 * send it to the lower layer
	 * if we get -1 return then put the request in the pending
	 * queue.
	 */
	rval = fc_fcp_pkt_send(lp, fsp);
	if (rval != 0) {
		fsp->state = FC_SRB_FREE;
		fc_fcp_pkt_release(fsp);
		rc = SCSI_MLQUEUE_HOST_BUSY;
	}
out:
	return rc;
}
EXPORT_SYMBOL(fc_queuecommand);

/**
1753
 * fc_io_compl() -  Handle responses for completed commands
1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766
 * @fsp:	scsi packet
 *
 * Translates a error to a Linux SCSI error.
 *
 * The fcp packet lock must be held when calling.
 */
static void fc_io_compl(struct fc_fcp_pkt *fsp)
{
	struct fc_fcp_internal *si;
	struct scsi_cmnd *sc_cmd;
	struct fc_lport *lp;
	unsigned long flags;

1767 1768 1769
	/* release outstanding ddp context */
	fc_fcp_ddp_done(fsp);

1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823
	fsp->state |= FC_SRB_COMPL;
	if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
		spin_unlock_bh(&fsp->scsi_pkt_lock);
		del_timer_sync(&fsp->timer);
		spin_lock_bh(&fsp->scsi_pkt_lock);
	}

	lp = fsp->lp;
	si = fc_get_scsi_internal(lp);
	spin_lock_irqsave(lp->host->host_lock, flags);
	if (!fsp->cmd) {
		spin_unlock_irqrestore(lp->host->host_lock, flags);
		return;
	}

	/*
	 * if a command timed out while we had to try and throttle IO
	 * and it is now getting cleaned up, then we are about to
	 * try again so clear the throttled flag incase we get more
	 * time outs.
	 */
	if (si->throttled && fsp->state & FC_SRB_NOMEM)
		si->throttled = 0;

	sc_cmd = fsp->cmd;
	fsp->cmd = NULL;

	if (!sc_cmd->SCp.ptr) {
		spin_unlock_irqrestore(lp->host->host_lock, flags);
		return;
	}

	CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status;
	switch (fsp->status_code) {
	case FC_COMPLETE:
		if (fsp->cdb_status == 0) {
			/*
			 * good I/O status
			 */
			sc_cmd->result = DID_OK << 16;
			if (fsp->scsi_resid)
				CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
		} else {
			/*
			 * transport level I/O was ok but scsi
			 * has non zero status
			 */
			sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
		}
		break;
	case FC_ERROR:
		sc_cmd->result = DID_ERROR << 16;
		break;
	case FC_DATA_UNDRUN:
1824
		if ((fsp->cdb_status == 0) && !(fsp->req_flags & FC_SRB_READ)) {
1825 1826
			/*
			 * scsi status is good but transport level
1827
			 * underrun.
1828
			 */
1829 1830
			sc_cmd->result = (fsp->state & FC_SRB_RCV_STATUS ?
					  DID_OK : DID_ERROR) << 16;
1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845
		} else {
			/*
			 * scsi got underrun, this is an error
			 */
			CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
			sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
		}
		break;
	case FC_DATA_OVRRUN:
		/*
		 * overrun is an error
		 */
		sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
		break;
	case FC_CMD_ABORTED:
1846
		sc_cmd->result = (DID_ERROR << 16) | fsp->io_status;
1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871
		break;
	case FC_CMD_TIME_OUT:
		sc_cmd->result = (DID_BUS_BUSY << 16) | fsp->io_status;
		break;
	case FC_CMD_RESET:
		sc_cmd->result = (DID_RESET << 16);
		break;
	case FC_HRD_ERROR:
		sc_cmd->result = (DID_NO_CONNECT << 16);
		break;
	default:
		sc_cmd->result = (DID_ERROR << 16);
		break;
	}

	list_del(&fsp->list);
	sc_cmd->SCp.ptr = NULL;
	sc_cmd->scsi_done(sc_cmd);
	spin_unlock_irqrestore(lp->host->host_lock, flags);

	/* release ref from initial allocation in queue command */
	fc_fcp_pkt_release(fsp);
}

/**
1872
 * fc_eh_abort() - Abort a command
1873 1874
 * @sc_cmd:	scsi command to abort
 *
1875
 * From scsi host template.
1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888
 * send ABTS to the target device  and wait for the response
 * sc_cmd is the pointer to the command to be aborted.
 */
int fc_eh_abort(struct scsi_cmnd *sc_cmd)
{
	struct fc_fcp_pkt *fsp;
	struct fc_lport *lp;
	int rc = FAILED;
	unsigned long flags;

	lp = shost_priv(sc_cmd->device->host);
	if (lp->state != LPORT_ST_READY)
		return rc;
1889
	else if (!lp->link_up)
1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908
		return rc;

	spin_lock_irqsave(lp->host->host_lock, flags);
	fsp = CMD_SP(sc_cmd);
	if (!fsp) {
		/* command completed while scsi eh was setting up */
		spin_unlock_irqrestore(lp->host->host_lock, flags);
		return SUCCESS;
	}
	/* grab a ref so the fsp and sc_cmd cannot be relased from under us */
	fc_fcp_pkt_hold(fsp);
	spin_unlock_irqrestore(lp->host->host_lock, flags);

	if (fc_fcp_lock_pkt(fsp)) {
		/* completed while we were waiting for timer to be deleted */
		rc = SUCCESS;
		goto release_pkt;
	}

1909
	rc = fc_fcp_pkt_abort(fsp);
1910 1911 1912 1913 1914 1915 1916 1917 1918
	fc_fcp_unlock_pkt(fsp);

release_pkt:
	fc_fcp_pkt_release(fsp);
	return rc;
}
EXPORT_SYMBOL(fc_eh_abort);

/**
1919
 * fc_eh_device_reset() Reset a single LUN
1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943
 * @sc_cmd:	scsi command
 *
 * Set from scsi host template to send tm cmd to the target and wait for the
 * response.
 */
int fc_eh_device_reset(struct scsi_cmnd *sc_cmd)
{
	struct fc_lport *lp;
	struct fc_fcp_pkt *fsp;
	struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
	int rc = FAILED;
	struct fc_rport_libfc_priv *rp;
	int rval;

	rval = fc_remote_port_chkready(rport);
	if (rval)
		goto out;

	rp = rport->dd_data;
	lp = shost_priv(sc_cmd->device->host);

	if (lp->state != LPORT_ST_READY)
		return rc;

1944 1945
	FC_SCSI_DBG(lp, "Resetting rport (%6x)\n", rport->port_id);

1946 1947
	fsp = fc_fcp_pkt_alloc(lp, GFP_NOIO);
	if (fsp == NULL) {
1948
		printk(KERN_WARNING "libfc: could not allocate scsi_pkt\n");
1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973
		sc_cmd->result = DID_NO_CONNECT << 16;
		goto out;
	}

	/*
	 * Build the libfc request pkt. Do not set the scsi cmnd, because
	 * the sc passed in is not setup for execution like when sent
	 * through the queuecommand callout.
	 */
	fsp->lp = lp;		/* save the softc ptr */
	fsp->rport = rport;	/* set the remote port ptr */

	/*
	 * flush outstanding commands
	 */
	rc = fc_lun_reset(lp, fsp, scmd_id(sc_cmd), sc_cmd->device->lun);
	fsp->state = FC_SRB_FREE;
	fc_fcp_pkt_release(fsp);

out:
	return rc;
}
EXPORT_SYMBOL(fc_eh_device_reset);

/**
1974
 * fc_eh_host_reset() - The reset function will reset the ports on the host.
1975 1976 1977 1978 1979 1980 1981 1982
 * @sc_cmd:	scsi command
 */
int fc_eh_host_reset(struct scsi_cmnd *sc_cmd)
{
	struct Scsi_Host *shost = sc_cmd->device->host;
	struct fc_lport *lp = shost_priv(shost);
	unsigned long wait_tmo;

1983 1984
	FC_SCSI_DBG(lp, "Resetting host\n");

1985 1986 1987 1988 1989 1990
	lp->tt.lport_reset(lp);
	wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT;
	while (!fc_fcp_lport_queue_ready(lp) && time_before(jiffies, wait_tmo))
		msleep(1000);

	if (fc_fcp_lport_queue_ready(lp)) {
1991 1992
		shost_printk(KERN_INFO, shost, "libfc: Host reset succeeded "
			     "on port (%6x)\n", fc_host_port_id(lp->host));
1993 1994
		return SUCCESS;
	} else {
1995 1996 1997
		shost_printk(KERN_INFO, shost, "libfc: Host reset failed, "
			     "port (%6x) is not ready.\n",
			     fc_host_port_id(lp->host));
1998 1999 2000 2001 2002 2003
		return FAILED;
	}
}
EXPORT_SYMBOL(fc_eh_host_reset);

/**
2004
 * fc_slave_alloc() - configure queue depth
2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016
 * @sdev:	scsi device
 *
 * Configures queue depth based on host's cmd_per_len. If not set
 * then we use the libfc default.
 */
int fc_slave_alloc(struct scsi_device *sdev)
{
	struct fc_rport *rport = starget_to_rport(scsi_target(sdev));

	if (!rport || fc_remote_port_chkready(rport))
		return -ENXIO;

2017 2018 2019 2020 2021 2022
	if (sdev->tagged_supported)
		scsi_activate_tcq(sdev, FC_FCP_DFLT_QUEUE_DEPTH);
	else
		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev),
					FC_FCP_DFLT_QUEUE_DEPTH);

2023 2024 2025 2026
	return 0;
}
EXPORT_SYMBOL(fc_slave_alloc);

2027
int fc_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason)
2028
{
2029 2030 2031 2032 2033 2034 2035
	switch (reason) {
	case SCSI_QDEPTH_DEFAULT:
		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
		break;
	case SCSI_QDEPTH_QFULL:
		scsi_track_queue_full(sdev, qdepth);
		break;
V
Vasu Dev 已提交
2036 2037 2038
	case SCSI_QDEPTH_RAMP_UP:
		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
		break;
2039
	default:
2040
		return -EOPNOTSUPP;
2041
	}
2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065
	return sdev->queue_depth;
}
EXPORT_SYMBOL(fc_change_queue_depth);

int fc_change_queue_type(struct scsi_device *sdev, int tag_type)
{
	if (sdev->tagged_supported) {
		scsi_set_tag_type(sdev, tag_type);
		if (tag_type)
			scsi_activate_tcq(sdev, sdev->queue_depth);
		else
			scsi_deactivate_tcq(sdev, sdev->queue_depth);
	} else
		tag_type = 0;

	return tag_type;
}
EXPORT_SYMBOL(fc_change_queue_type);

void fc_fcp_destroy(struct fc_lport *lp)
{
	struct fc_fcp_internal *si = fc_get_scsi_internal(lp);

	if (!list_empty(&si->scsi_pkt_queue))
2066 2067
		printk(KERN_ERR "libfc: Leaked SCSI packets when destroying "
		       "port (%6x)\n", fc_host_port_id(lp->host));
2068 2069 2070 2071 2072 2073 2074

	mempool_destroy(si->scsi_pkt_pool);
	kfree(si);
	lp->scsi_priv = NULL;
}
EXPORT_SYMBOL(fc_fcp_destroy);

2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096
int fc_setup_fcp()
{
	int rc = 0;

	scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt",
					    sizeof(struct fc_fcp_pkt),
					    0, SLAB_HWCACHE_ALIGN, NULL);
	if (!scsi_pkt_cachep) {
		printk(KERN_ERR "libfc: Unable to allocate SRB cache, "
		       "module load failed!");
		rc = -ENOMEM;
	}

	return rc;
}

void fc_destroy_fcp()
{
	if (scsi_pkt_cachep)
		kmem_cache_destroy(scsi_pkt_cachep);
}

2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128
int fc_fcp_init(struct fc_lport *lp)
{
	int rc;
	struct fc_fcp_internal *si;

	if (!lp->tt.fcp_cmd_send)
		lp->tt.fcp_cmd_send = fc_fcp_cmd_send;

	if (!lp->tt.fcp_cleanup)
		lp->tt.fcp_cleanup = fc_fcp_cleanup;

	if (!lp->tt.fcp_abort_io)
		lp->tt.fcp_abort_io = fc_fcp_abort_io;

	si = kzalloc(sizeof(struct fc_fcp_internal), GFP_KERNEL);
	if (!si)
		return -ENOMEM;
	lp->scsi_priv = si;
	INIT_LIST_HEAD(&si->scsi_pkt_queue);

	si->scsi_pkt_pool = mempool_create_slab_pool(2, scsi_pkt_cachep);
	if (!si->scsi_pkt_pool) {
		rc = -ENOMEM;
		goto free_internal;
	}
	return 0;

free_internal:
	kfree(si);
	return rc;
}
EXPORT_SYMBOL(fc_fcp_init);