path: root/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c

/*******************************************************************************

  Intel 10 Gigabit PCI Express Linux driver
  Copyright(c) 1999 - 2013 Intel Corporation.

  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.

  The full GNU General Public License is included in this distribution in
  the file called "COPYING".

  Contact Information:
  e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
  Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497

*******************************************************************************/

#include "ixgbe.h"
#include <linux/if_ether.h>
#include <linux/gfp.h>
#include <linux/if_vlan.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/fc/fc_fs.h>
#include <scsi/fc/fc_fcoe.h>
#include <scsi/libfc.h>
#include <scsi/libfcoe.h>

/**
 * ixgbe_fcoe_clear_ddp - clear the given ddp context
 * @ddp: ptr to the ixgbe_fcoe_ddp
 *
 * Returns : none
 *
 */
static inline void ixgbe_fcoe_clear_ddp(struct ixgbe_fcoe_ddp *ddp)
{
	ddp->len = 0;
	ddp->err = 1;
	ddp->udl = NULL;
	ddp->udp = 0UL;
	ddp->sgl = NULL;
	ddp->sgc = 0;
}

/**
 * ixgbe_fcoe_ddp_put - free the ddp context for a given xid
 * @netdev: the corresponding net_device
 * @xid: the xid that corresponding ddp will be freed
 *
 * This is the implementation of net_device_ops.ndo_fcoe_ddp_done
 * and it is expected to be called by ULD, i.e., FCP layer of libfc
 * to release the corresponding ddp context when the I/O is done.
 *
 * Returns : data length already ddp-ed in bytes
 */
int ixgbe_fcoe_ddp_put(struct net_device *netdev, u16 xid)
{
	int len = 0;
	struct ixgbe_fcoe *fcoe;
	struct ixgbe_adapter *adapter;
	struct ixgbe_fcoe_ddp *ddp;
	u32 fcbuff;

	if (!netdev)
		goto out_ddp_put;

	if (xid >= IXGBE_FCOE_DDP_MAX)
		goto out_ddp_put;

	adapter = netdev_priv(netdev);
	fcoe = &adapter->fcoe;
	ddp = &fcoe->ddp[xid];
	if (!ddp->udl)
		goto out_ddp_put;

	len = ddp->len;
	/* if there an error, force to invalidate ddp context */
	if (ddp->err) {
		spin_lock_bh(&fcoe->lock);
		IXGBE_WRITE_REG(&adapter->hw, IXGBE_FCFLT, 0);
		IXGBE_WRITE_REG(&adapter->hw, IXGBE_FCFLTRW,
				(xid | IXGBE_FCFLTRW_WE));
		IXGBE_WRITE_REG(&adapter->hw, IXGBE_FCBUFF, 0);
		IXGBE_WRITE_REG(&adapter->hw, IXGBE_FCDMARW,
				(xid | IXGBE_FCDMARW_WE));

		/* guaranteed to be invalidated after 100us */
		IXGBE_WRITE_REG(&adapter->hw, IXGBE_FCDMARW,
				(xid | IXGBE_FCDMARW_RE));
		fcbuff = IXGBE_READ_REG(&adapter->hw, IXGBE_FCBUFF);
		spin_unlock_bh(&fcoe->lock);
		if (fcbuff & IXGBE_FCBUFF_VALID)
			udelay(100);
	}
	if (ddp->sgl)
		dma_unmap_sg(&adapter->pdev->dev, ddp->sgl, ddp->sgc,
			     DMA_FROM_DEVICE);
	if (ddp->pool) {
		dma_pool_free(ddp->pool, ddp->udl, ddp->udp);
		ddp->pool = NULL;
	}

	ixgbe_fcoe_clear_ddp(ddp);

out_ddp_put:
	return len;
}

/**
 * ixgbe_fcoe_ddp_setup - called to set up ddp context
 * @netdev: the corresponding net_device
 * @xid: the exchange id requesting ddp
 * @sgl: the scatter-gather list for this request
 * @sgc: the number of scatter-gather items
 *
 * Returns : 1 for success and 0 for no ddp
 */
static int ixgbe_fcoe_ddp_setup(struct net_device *netdev, u16 xid,
				struct scatterlist *sgl, unsigned int sgc,
				int target_mode)
{
	struct ixgbe_adapter *adapter;
	struct ixgbe_hw *hw;
	struct ixgbe_fcoe *fcoe;
	struct ixgbe_fcoe_ddp *ddp;
	struct ixgbe_fcoe_ddp_pool *ddp_pool;
	struct scatterlist *sg;
	unsigned int i, j, dmacount;
	unsigned int len;
	static const unsigned int bufflen = IXGBE_FCBUFF_MIN;
	unsigned int firstoff = 0;
	unsigned int lastsize;
	unsigned int thisoff = 0;
	unsigned int thislen = 0;
	u32 fcbuff, fcdmarw, fcfltrw, fcrxctl;
	dma_addr_t addr = 0;

	if (!netdev || !sgl)
		return 0;

	adapter = netdev_priv(netdev);
	if (xid >= IXGBE_FCOE_DDP_MAX) {
		e_warn(drv, "xid=0x%x out-of-range\n", xid);
		return 0;
	}

	/* no DDP if we are already down or resetting */
	if (test_bit(