/*
 * Copyright 2008 Cisco Systems, Inc.  All rights reserved.
 * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
 *
 * This program is free software; you may redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
#include <linux/mempool.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/workqueue.h>
#include <linux/pci.h>
#include <linux/scatterlist.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <linux/delay.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_tcq.h>
#include <scsi/fc/fc_els.h>
#include <scsi/fc/fc_fcoe.h>
#include <scsi/libfc.h>
#include <scsi/fc_frame.h>
#include "fnic_io.h"
#include "fnic.h"

const char *fnic_state_str[] = {
        [FNIC_IN_FC_MODE] =           "FNIC_IN_FC_MODE",
        [FNIC_IN_FC_TRANS_ETH_MODE] = "FNIC_IN_FC_TRANS_ETH_MODE",
        [FNIC_IN_ETH_MODE] =          "FNIC_IN_ETH_MODE",
        [FNIC_IN_ETH_TRANS_FC_MODE] = "FNIC_IN_ETH_TRANS_FC_MODE",
};

static const char *fnic_ioreq_state_str[] = {
        [FNIC_IOREQ_CMD_PENDING] = "FNIC_IOREQ_CMD_PENDING",
        [FNIC_IOREQ_ABTS_PENDING] = "FNIC_IOREQ_ABTS_PENDING",
        [FNIC_IOREQ_ABTS_COMPLETE] = "FNIC_IOREQ_ABTS_COMPLETE",
        [FNIC_IOREQ_CMD_COMPLETE] = "FNIC_IOREQ_CMD_COMPLETE",
};

static const char *fcpio_status_str[] =  {
        [FCPIO_SUCCESS] = "FCPIO_SUCCESS", /*0x0*/
        [FCPIO_INVALID_HEADER] = "FCPIO_INVALID_HEADER",
        [FCPIO_OUT_OF_RESOURCE] = "FCPIO_OUT_OF_RESOURCE",
        [FCPIO_INVALID_PARAM] = "FCPIO_INVALID_PARAM]",
        [FCPIO_REQ_NOT_SUPPORTED] = "FCPIO_REQ_NOT_SUPPORTED",
        [FCPIO_IO_NOT_FOUND] = "FCPIO_IO_NOT_FOUND",
        [FCPIO_ABORTED] = "FCPIO_ABORTED", /*0x41*/
        [FCPIO_TIMEOUT] = "FCPIO_TIMEOUT",
        [FCPIO_SGL_INVALID] = "FCPIO_SGL_INVALID",
        [FCPIO_MSS_INVALID] = "FCPIO_MSS_INVALID",
        [FCPIO_DATA_CNT_MISMATCH] = "FCPIO_DATA_CNT_MISMATCH",
        [FCPIO_FW_ERR] = "FCPIO_FW_ERR",
        [FCPIO_ITMF_REJECTED] = "FCPIO_ITMF_REJECTED",
        [FCPIO_ITMF_FAILED] = "FCPIO_ITMF_FAILED",
        [FCPIO_ITMF_INCORRECT_LUN] = "FCPIO_ITMF_INCORRECT_LUN",
        [FCPIO_CMND_REJECTED] = "FCPIO_CMND_REJECTED",
        [FCPIO_NO_PATH_AVAIL] = "FCPIO_NO_PATH_AVAIL",
        [FCPIO_PATH_FAILED] = "FCPIO_PATH_FAILED",
        [FCPIO_LUNMAP_CHNG_PEND] = "FCPIO_LUNHMAP_CHNG_PEND",
};

const char *fnic_state_to_str(unsigned int state)
{
        if (state >= ARRAY_SIZE(fnic_state_str) || !fnic_state_str[state])
                return "unknown";

        return fnic_state_str[state];
}

static const char *fnic_ioreq_state_to_str(unsigned int state)
{
        if (state >= ARRAY_SIZE(fnic_ioreq_state_str) ||
            !fnic_ioreq_state_str[state])
                return "unknown";

        return fnic_ioreq_state_str[state];
}

static const char *fnic_fcpio_status_to_str(unsigned int status)
{
        if (status >= ARRAY_SIZE(fcpio_status_str) || !fcpio_status_str[status])
                return "unknown";

        return fcpio_status_str[status];
}

static void fnic_cleanup_io(struct fnic *fnic, int exclude_id);

static inline spinlock_t *fnic_io_lock_hash(struct fnic *fnic,
                                            struct scsi_cmnd *sc)
{
        u32 hash = sc->request->tag & (FNIC_IO_LOCKS - 1);

        return &fnic->io_req_lock[hash];
}

/*
 * Unmap the data buffer and sense buffer for an io_req,
 * also unmap and free the device-private scatter/gather list.
 */
static void fnic_release_ioreq_buf(struct fnic *fnic,
                                   struct fnic_io_req *io_req,
                                   struct scsi_cmnd *sc)
{
        if (io_req->sgl_list_pa)
                pci_unmap_single(fnic->pdev, io_req->sgl_list_pa,
                                 sizeof(io_req->sgl_list[0]) * io_req->sgl_cnt,
                                 PCI_DMA_TODEVICE);
        scsi_dma_unmap(sc);

        if (io_req->sgl_cnt)
                mempool_free(io_req->sgl_list_alloc,
                             fnic->io_sgl_pool[io_req->sgl_type]);
        if (io_req->sense_buf_pa)
                pci_unmap_single(fnic->pdev, io_req->sense_buf_pa,
                                 SCSI_SENSE_BUFFERSIZE, PCI_DMA_FROMDEVICE);
}

/* Free up Copy Wq descriptors. Called with copy_wq lock held */
static int free_wq_copy_descs(struct fnic *fnic, struct vnic_wq_copy *wq)
{
        /* if no Ack received from firmware, then nothing to clean */
        if (!fnic->fw_ack_recd[0])
                return 1;

        /*
         * Update desc_available count based on number of freed descriptors
         * Account for wraparound
         */
        if (wq->to_clean_index <= fnic->fw_ack_index[0])
                wq->ring.desc_avail += (fnic->fw_ack_index[0]
                                        - wq->to_clean_index + 1);
        else
                wq->ring.desc_avail += (wq->ring.desc_count
                                        - wq->to_clean_index
                                        + fnic->fw_ack_index[0] + 1);

        /*
         * just bump clean index to ack_index+1 accounting for wraparound
         * this will essentially free up all descriptors between
         * to_clean_index and fw_ack_index, both inclusive
         */
        wq->to_clean_index =
                (fnic->fw_ack_index[0] + 1) % wq->ring.desc_count;

        /* we have processed the acks received so far */
        fnic->fw_ack_recd[0] = 0;
        return 0;
}


/*
 * fnic_fw_reset_handler
 * Routine to send reset msg to fw
 */
int fnic_fw_reset_handler(struct fnic *fnic)
{
        struct vnic_wq_copy *wq = &fnic->wq_copy[0];
        int ret = 0;
        unsigned long flags;

        spin_lock_irqsave(&fnic->wq_copy_lock[0], flags);

        if (vnic_wq_copy_desc_avail(wq) <= fnic->wq_copy_desc_low[0])
                free_wq_copy_descs(fnic, wq);

        if (!vnic_wq_copy_desc_avail(wq))
                ret = -EAGAIN;
        else
                fnic_queue_wq_copy_desc_fw_reset(wq, SCSI_NO_TAG);

        spin_unlock_irqrestore(&fnic->wq_copy_lock[0], flags);

        if (!ret)
                FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                              "Issued fw reset\n");
        else
                FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                              "Failed to issue fw reset\n");
        return ret;
}


/*
 * fnic_flogi_reg_handler
 * Routine to send flogi register msg to fw
 */
int fnic_flogi_reg_handler(struct fnic *fnic)
{
        struct vnic_wq_copy *wq = &fnic->wq_copy[0];
        u8 gw_mac[ETH_ALEN];
        int ret = 0;
        unsigned long flags;

        spin_lock_irqsave(&fnic->wq_copy_lock[0], flags);

        if (vnic_wq_copy_desc_avail(wq) <= fnic->wq_copy_desc_low[0])
                free_wq_copy_descs(fnic, wq);

        if (!vnic_wq_copy_desc_avail(wq)) {
                ret = -EAGAIN;
                goto flogi_reg_ioreq_end;
        }

        if (fnic->fcoui_mode)
                memset(gw_mac, 0xff, ETH_ALEN);
        else
                memcpy(gw_mac, fnic->dest_addr, ETH_ALEN);

        fnic_queue_wq_copy_desc_flogi_reg(wq, SCSI_NO_TAG,
                                          FCPIO_FLOGI_REG_GW_DEST,
                                          fnic->s_id,
                                          gw_mac);

flogi_reg_ioreq_end:
        spin_unlock_irqrestore(&fnic->wq_copy_lock[0], flags);

        if (!ret)
                FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                              "flog reg issued\n");

        return ret;
}

/*
 * fnic_queue_wq_copy_desc
 * Routine to enqueue a wq copy desc
 */
static inline int fnic_queue_wq_copy_desc(struct fnic *fnic,
                                          struct vnic_wq_copy *wq,
                                          struct fnic_io_req *io_req,
                                          struct scsi_cmnd *sc,
                                          int sg_count)
{
        struct scatterlist *sg;
        struct fc_rport *rport = starget_to_rport(scsi_target(sc->device));
        struct fc_rport_libfc_priv *rp = rport->dd_data;
        struct host_sg_desc *desc;
        u8 pri_tag = 0;
        unsigned int i;
        unsigned long intr_flags;
        int flags;
        u8 exch_flags;
        struct scsi_lun fc_lun;
        char msg[2];

        if (sg_count) {
                /* For each SGE, create a device desc entry */
                desc = io_req->sgl_list;
                for_each_sg(scsi_sglist(sc), sg, sg_count, i) {
                        desc->addr = cpu_to_le64(sg_dma_address(sg));
                        desc->len = cpu_to_le32(sg_dma_len(sg));
                        desc->_resvd = 0;
                        desc++;
                }

                io_req->sgl_list_pa = pci_map_single
                        (fnic->pdev,
                         io_req->sgl_list,
                         sizeof(io_req->sgl_list[0]) * sg_count,
                         PCI_DMA_TODEVICE);
        }

        io_req->sense_buf_pa = pci_map_single(fnic->pdev,
                                              sc->sense_buffer,
                                              SCSI_SENSE_BUFFERSIZE,
                                              PCI_DMA_FROMDEVICE);

        int_to_scsilun(sc->device->lun, &fc_lun);

        pri_tag = FCPIO_ICMND_PTA_SIMPLE;
        msg[0] = MSG_SIMPLE_TAG;
        scsi_populate_tag_msg(sc, msg);
        if (msg[0] == MSG_ORDERED_TAG)
                pri_tag = FCPIO_ICMND_PTA_ORDERED;

        /* Enqueue the descriptor in the Copy WQ */
        spin_lock_irqsave(&fnic->wq_copy_lock[0], intr_flags);

        if (vnic_wq_copy_desc_avail(wq) <= fnic->wq_copy_desc_low[0])
                free_wq_copy_descs(fnic, wq);

        if (unlikely(!vnic_wq_copy_desc_avail(wq))) {
                spin_unlock_irqrestore(&fnic->wq_copy_lock[0], intr_flags);
                return SCSI_MLQUEUE_HOST_BUSY;
        }

        flags = 0;
        if (sc->sc_data_direction == DMA_FROM_DEVICE)
                flags = FCPIO_ICMND_RDDATA;
        else if (sc->sc_data_direction == DMA_TO_DEVICE)
                flags = FCPIO_ICMND_WRDATA;

        exch_flags = 0;
        if ((fnic->config.flags & VFCF_FCP_SEQ_LVL_ERR) &&
            (rp->flags & FC_RP_FLAGS_RETRY))
                exch_flags |= FCPIO_ICMND_SRFLAG_RETRY;

        fnic_queue_wq_copy_desc_icmnd_16(wq, sc->request->tag,
                                         0, exch_flags, io_req->sgl_cnt,
                                         SCSI_SENSE_BUFFERSIZE,
                                         io_req->sgl_list_pa,
                                         io_req->sense_buf_pa,
                                         0, /* scsi cmd ref, always 0 */
                                         pri_tag, /* scsi pri and tag */
                                         flags, /* command flags */
                                         sc->cmnd, scsi_bufflen(sc),
                                         fc_lun.scsi_lun, io_req->port_id,
                                         rport->maxframe_size, rp->r_a_tov,
                                         rp->e_d_tov);

        spin_unlock_irqrestore(&fnic->wq_copy_lock[0], intr_flags);
        return 0;
}

/*
 * fnic_queuecommand
 * Routine to send a scsi cdb
 * Called with host_lock held and interrupts disabled.
 */
int fnic_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
{
        struct fc_lport *lp;
        struct fc_rport *rport;
        struct fnic_io_req *io_req;
        struct fnic *fnic;
        struct vnic_wq_copy *wq;
        int ret;
        int sg_count;
        unsigned long flags;
        unsigned long ptr;

        rport = starget_to_rport(scsi_target(sc->device));
        ret = fc_remote_port_chkready(rport);
        if (ret) {
                sc->result = ret;
                done(sc);
                return 0;
        }

        lp = shost_priv(sc->device->host);
        if (lp->state != LPORT_ST_READY || !(lp->link_up))
                return SCSI_MLQUEUE_HOST_BUSY;

        /*
         * Release host lock, use driver resource specific locks from here.
         * Don't re-enable interrupts in case they were disabled prior to the
         * caller disabling them.
         */
        spin_unlock(lp->host->host_lock);

        /* Get a new io_req for this SCSI IO */
        fnic = lport_priv(lp);

        io_req = mempool_alloc(fnic->io_req_pool, GFP_ATOMIC);
        if (!io_req) {
                ret = SCSI_MLQUEUE_HOST_BUSY;
                goto out;
        }
        memset(io_req, 0, sizeof(*io_req));

        /* Map the data buffer */
        sg_count = scsi_dma_map(sc);
        if (sg_count < 0) {
                mempool_free(io_req, fnic->io_req_pool);
                goto out;
        }

        /* Determine the type of scatter/gather list we need */
        io_req->sgl_cnt = sg_count;
        io_req->sgl_type = FNIC_SGL_CACHE_DFLT;
        if (sg_count > FNIC_DFLT_SG_DESC_CNT)
                io_req->sgl_type = FNIC_SGL_CACHE_MAX;

        if (sg_count) {
                io_req->sgl_list =
                        mempool_alloc(fnic->io_sgl_pool[io_req->sgl_type],
                                      GFP_ATOMIC | GFP_DMA);
                if (!io_req->sgl_list) {
                        ret = SCSI_MLQUEUE_HOST_BUSY;
                        scsi_dma_unmap(sc);
                        mempool_free(io_req, fnic->io_req_pool);
                        goto out;
                }

                /* Cache sgl list allocated address before alignment */
                io_req->sgl_list_alloc = io_req->sgl_list;
                ptr = (unsigned long) io_req->sgl_list;
                if (ptr % FNIC_SG_DESC_ALIGN) {
                        io_req->sgl_list = (struct host_sg_desc *)
                                (((unsigned long) ptr
                                  + FNIC_SG_DESC_ALIGN - 1)
                                 & ~(FNIC_SG_DESC_ALIGN - 1));
                }
        }

        /* initialize rest of io_req */
        io_req->port_id = rport->port_id;
        CMD_STATE(sc) = FNIC_IOREQ_CMD_PENDING;
        CMD_SP(sc) = (char *)io_req;
        sc->scsi_done = done;

        /* create copy wq desc and enqueue it */
        wq = &fnic->wq_copy[0];
        ret = fnic_queue_wq_copy_desc(fnic, wq, io_req, sc, sg_count);
        if (ret) {
                /*
                 * In case another thread cancelled the request,
                 * refetch the pointer under the lock.
                 */
                spinlock_t *io_lock = fnic_io_lock_hash(fnic, sc);

                spin_lock_irqsave(io_lock, flags);
                io_req = (struct fnic_io_req *)CMD_SP(sc);
                CMD_SP(sc) = NULL;
                CMD_STATE(sc) = FNIC_IOREQ_CMD_COMPLETE;
                spin_unlock_irqrestore(io_lock, flags);
                if (io_req) {
                        fnic_release_ioreq_buf(fnic, io_req, sc);
                        mempool_free(io_req, fnic->io_req_pool);
                }
        }
out:
        /* acquire host lock before returning to SCSI */
        spin_lock(lp->host->host_lock);
        return ret;
}

/*
 * fnic_fcpio_fw_reset_cmpl_handler
 * Routine to handle fw reset completion
 */
static int fnic_fcpio_fw_reset_cmpl_handler(struct fnic *fnic,
                                            struct fcpio_fw_req *desc)
{
        u8 type;
        u8 hdr_status;
        struct fcpio_tag tag;
        int ret = 0;
        struct fc_frame *flogi;
        unsigned long flags;

        fcpio_header_dec(&desc->hdr, &type, &hdr_status, &tag);

        /* Clean up all outstanding io requests */
        fnic_cleanup_io(fnic, SCSI_NO_TAG);

        spin_lock_irqsave(&fnic->fnic_lock, flags);

        flogi = fnic->flogi;
        fnic->flogi = NULL;

        /* fnic should be in FC_TRANS_ETH_MODE */
        if (fnic->state == FNIC_IN_FC_TRANS_ETH_MODE) {
                /* Check status of reset completion */
                if (!hdr_status) {
                        FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                                      "reset cmpl success\n");
                        /* Ready to send flogi out */
                        fnic->state = FNIC_IN_ETH_MODE;
                } else {
                        FNIC_SCSI_DBG(KERN_DEBUG,
                                      fnic->lport->host,
                                      "fnic fw_reset : failed %s\n",
                                      fnic_fcpio_status_to_str(hdr_status));

                        /*
                         * Unable to change to eth mode, cannot send out flogi
                         * Change state to fc mode, so that subsequent Flogi
                         * requests from libFC will cause more attempts to
                         * reset the firmware. Free the cached flogi
                         */
                        fnic->state = FNIC_IN_FC_MODE;
                        ret = -1;
                }
        } else {
                FNIC_SCSI_DBG(KERN_DEBUG,
                              fnic->lport->host,
                              "Unexpected state %s while processing"
                              " reset cmpl\n", fnic_state_to_str(fnic->state));
                ret = -1;
        }

        /* Thread removing device blocks till firmware reset is complete */
        if (fnic->remove_wait)
                complete(fnic->remove_wait);

        /*
         * If fnic is being removed, or fw reset failed
         * free the flogi frame. Else, send it out
         */
        if (fnic->remove_wait || ret) {
                fnic->flogi_oxid = FC_XID_UNKNOWN;
                spin_unlock_irqrestore(&fnic->fnic_lock, flags);
                if (flogi)
                        dev_kfree_skb_irq(fp_skb(flogi));
                goto reset_cmpl_handler_end;
        }

        spin_unlock_irqrestore(&fnic->fnic_lock, flags);

        if (flogi)
                ret = fnic_send_frame(fnic, flogi);

 reset_cmpl_handler_end:
        return ret;
}

/*
 * fnic_fcpio_flogi_reg_cmpl_handler
 * Routine to handle flogi register completion
 */
static int fnic_fcpio_flogi_reg_cmpl_handler(struct fnic *fnic,
                                             struct fcpio_fw_req *desc)
{
        u8 type;
        u8 hdr_status;
        struct fcpio_tag tag;
        int ret = 0;
        struct fc_frame *flogi_resp = NULL;
        unsigned long flags;
        struct sk_buff *skb;

        fcpio_header_dec(&desc->hdr, &type, &hdr_status, &tag);

        /* Update fnic state based on status of flogi reg completion */
        spin_lock_irqsave(&fnic->fnic_lock, flags);

        flogi_resp = fnic->flogi_resp;
        fnic->flogi_resp = NULL;

        if (fnic->state == FNIC_IN_ETH_TRANS_FC_MODE) {

                /* Check flogi registration completion status */
                if (!hdr_status) {
                        FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                                      "flog reg succeeded\n");
                        fnic->state = FNIC_IN_FC_MODE;
                } else {
                        FNIC_SCSI_DBG(KERN_DEBUG,
                                      fnic->lport->host,
                                      "fnic flogi reg :failed %s\n",
                                      fnic_fcpio_status_to_str(hdr_status));
                        fnic->state = FNIC_IN_ETH_MODE;
                        ret = -1;
                }
        } else {
                FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                              "Unexpected fnic state %s while"
                              " processing flogi reg completion\n",
                              fnic_state_to_str(fnic->state));
                ret = -1;
        }

        /* Successful flogi reg cmpl, pass frame to LibFC */
        if (!ret && flogi_resp) {
                if (fnic->stop_rx_link_events) {
                        spin_unlock_irqrestore(&fnic->fnic_lock, flags);
                        goto reg_cmpl_handler_end;
                }
                skb = (struct sk_buff *)flogi_resp;
                /* Use fr_flags to indicate whether flogi resp or not */
                fr_flags(flogi_resp) = 1;
                fr_dev(flogi_resp) = fnic->lport;
                spin_unlock_irqrestore(&fnic->fnic_lock, flags);

                skb_queue_tail(&fnic->frame_queue, skb);
                queue_work(fnic_event_queue, &fnic->frame_work);

        } else {
                spin_unlock_irqrestore(&fnic->fnic_lock, flags);
                if (flogi_resp)
                        dev_kfree_skb_irq(fp_skb(flogi_resp));
        }

reg_cmpl_handler_end:
        return ret;
}

static inline int is_ack_index_in_range(struct vnic_wq_copy *wq,
                                        u16 request_out)
{
        if (wq->to_clean_index <= wq->to_use_index) {
                /* out of range, stale request_out index */
                if (request_out < wq->to_clean_index ||
                    request_out >= wq->to_use_index)
                        return 0;
        } else {
                /* out of range, stale request_out index */
                if (request_out < wq->to_clean_index &&
                    request_out >= wq->to_use_index)
                        return 0;
        }
        /* request_out index is in range */
        return 1;
}


/*
 * Mark that ack received and store the Ack index. If there are multiple
 * acks received before Tx thread cleans it up, the latest value will be
 * used which is correct behavior. This state should be in the copy Wq
 * instead of in the fnic
 */
static inline void fnic_fcpio_ack_handler(struct fnic *fnic,
                                          unsigned int cq_index,
                                          struct fcpio_fw_req *desc)
{
        struct vnic_wq_copy *wq;
        u16 request_out = desc->u.ack.request_out;
        unsigned long flags;

        /* mark the ack state */
        wq = &fnic->wq_copy[cq_index - fnic->raw_wq_count - fnic->rq_count];
        spin_lock_irqsave(&fnic->wq_copy_lock[0], flags);

        if (is_ack_index_in_range(wq, request_out)) {
                fnic->fw_ack_index[0] = request_out;
                fnic->fw_ack_recd[0] = 1;
        }
        spin_unlock_irqrestore(&fnic->wq_copy_lock[0], flags);
}

/*
 * fnic_fcpio_icmnd_cmpl_handler
 * Routine to handle icmnd completions
 */
static void fnic_fcpio_icmnd_cmpl_handler(struct fnic *fnic,
                                         struct fcpio_fw_req *desc)
{
        u8 type;
        u8 hdr_status;
        struct fcpio_tag tag;
        u32 id;
        u64 xfer_len = 0;
        struct fcpio_icmnd_cmpl *icmnd_cmpl;
        struct fnic_io_req *io_req;
        struct scsi_cmnd *sc;
        unsigned long flags;
        spinlock_t *io_lock;

        /* Decode the cmpl description to get the io_req id */
        fcpio_header_dec(&desc->hdr, &type, &hdr_status, &tag);
        fcpio_tag_id_dec(&tag, &id);

        if (id >= FNIC_MAX_IO_REQ)
                return;

        sc = scsi_host_find_tag(fnic->lport->host, id);
        WARN_ON_ONCE(!sc);
        if (!sc)
                return;

        io_lock = fnic_io_lock_hash(fnic, sc);
        spin_lock_irqsave(io_lock, flags);
        io_req = (struct fnic_io_req *)CMD_SP(sc);
        WARN_ON_ONCE(!io_req);
        if (!io_req) {
                spin_unlock_irqrestore(io_lock, flags);
                return;
        }

        /* firmware completed the io */
        io_req->io_completed = 1;

        /*
         *  if SCSI-ML has already issued abort on this command,
         * ignore completion of the IO. The abts path will clean it up
         */
        if (CMD_STATE(sc) == FNIC_IOREQ_ABTS_PENDING) {
                spin_unlock_irqrestore(io_lock, flags);
                return;
        }

        /* Mark the IO as complete */
        CMD_STATE(sc) = FNIC_IOREQ_CMD_COMPLETE;

        icmnd_cmpl = &desc->u.icmnd_cmpl;

        switch (hdr_status) {
        case FCPIO_SUCCESS:
                sc->result = (DID_OK << 16) | icmnd_cmpl->scsi_status;
                xfer_len = scsi_bufflen(sc);
                scsi_set_resid(sc, icmnd_cmpl->residual);

                if (icmnd_cmpl->flags & FCPIO_ICMND_CMPL_RESID_UNDER)
                        xfer_len -= icmnd_cmpl->residual;

                /*
                 * If queue_full, then try to reduce queue depth for all
                 * LUNS on the target. Todo: this should be accompanied
                 * by a periodic queue_depth rampup based on successful
                 * IO completion.
                 */
                if (icmnd_cmpl->scsi_status == QUEUE_FULL) {
                        struct scsi_device *t_sdev;
                        int qd = 0;

                        shost_for_each_device(t_sdev, sc->device->host) {
                                if (t_sdev->id != sc->device->id)
                                        continue;

                                if (t_sdev->queue_depth > 1) {
                                        qd = scsi_track_queue_full
                                                (t_sdev,
                                                 t_sdev->queue_depth - 1);
                                        if (qd == -1)
                                                qd = t_sdev->host->cmd_per_lun;
                                        shost_printk(KERN_INFO,
                                                     fnic->lport->host,
                                                     "scsi[%d:%d:%d:%d"
                                                     "] queue full detected,"
                                                     "new depth = %d\n",
                                                     t_sdev->host->host_no,
                                                     t_sdev->channel,
                                                     t_sdev->id, t_sdev->lun,
                                                     t_sdev->queue_depth);
                                }
                        }
                }
                break;

        case FCPIO_TIMEOUT:          /* request was timed out */
                sc->result = (DID_TIME_OUT << 16) | icmnd_cmpl->scsi_status;
                break;

        case FCPIO_ABORTED:          /* request was aborted */
                sc->result = (DID_ERROR << 16) | icmnd_cmpl->scsi_status;
                break;

        case FCPIO_DATA_CNT_MISMATCH: /* recv/sent more/less data than exp. */
                scsi_set_resid(sc, icmnd_cmpl->residual);
                sc->result = (DID_ERROR << 16) | icmnd_cmpl->scsi_status;
                break;

        case FCPIO_OUT_OF_RESOURCE:  /* out of resources to complete request */
                sc->result = (DID_REQUEUE << 16) | icmnd_cmpl->scsi_status;
                break;
        case FCPIO_INVALID_HEADER:   /* header contains invalid data */
        case FCPIO_INVALID_PARAM:    /* some parameter in request invalid */
        case FCPIO_REQ_NOT_SUPPORTED:/* request type is not supported */
        case FCPIO_IO_NOT_FOUND:     /* requested I/O was not found */
        case FCPIO_SGL_INVALID:      /* request was aborted due to sgl error */
        case FCPIO_MSS_INVALID:      /* request was aborted due to mss error */
        case FCPIO_FW_ERR:           /* request was terminated due fw error */
        default:
                shost_printk(KERN_ERR, fnic->lport->host, "hdr status = %s\n",
                             fnic_fcpio_status_to_str(hdr_status));
                sc->result = (DID_ERROR << 16) | icmnd_cmpl->scsi_status;
                break;
        }

        /* Break link with the SCSI command */
        CMD_SP(sc) = NULL;

        spin_unlock_irqrestore(io_lock, flags);

        fnic_release_ioreq_buf(fnic, io_req, sc);

        mempool_free(io_req, fnic->io_req_pool);

        if (sc->sc_data_direction == DMA_FROM_DEVICE) {
                fnic->lport->host_stats.fcp_input_requests++;
                fnic->fcp_input_bytes += xfer_len;
        } else if (sc->sc_data_direction == DMA_TO_DEVICE) {
                fnic->lport->host_stats.fcp_output_requests++;
                fnic->fcp_output_bytes += xfer_len;
        } else
                fnic->lport->host_stats.fcp_control_requests++;

        /* Call SCSI completion function to complete the IO */
        if (sc->scsi_done)
                sc->scsi_done(sc);

}

/* fnic_fcpio_itmf_cmpl_handler
 * Routine to handle itmf completions
 */
static void fnic_fcpio_itmf_cmpl_handler(struct fnic *fnic,
                                        struct fcpio_fw_req *desc)
{
        u8 type;
        u8 hdr_status;
        struct fcpio_tag tag;
        u32 id;
        struct scsi_cmnd *sc;
        struct fnic_io_req *io_req;
        unsigned long flags;
        spinlock_t *io_lock;

        fcpio_header_dec(&desc->hdr, &type, &hdr_status, &tag);
        fcpio_tag_id_dec(&tag, &id);

        if ((id & FNIC_TAG_MASK) >= FNIC_MAX_IO_REQ)
                return;

        sc = scsi_host_find_tag(fnic->lport->host, id & FNIC_TAG_MASK);
        WARN_ON_ONCE(!sc);
        if (!sc)
                return;

        io_lock = fnic_io_lock_hash(fnic, sc);
        spin_lock_irqsave(io_lock, flags);
        io_req = (struct fnic_io_req *)CMD_SP(sc);
        WARN_ON_ONCE(!io_req);
        if (!io_req) {
                spin_unlock_irqrestore(io_lock, flags);
                return;
        }

        if (id & FNIC_TAG_ABORT) {
                /* Completion of abort cmd */
                if (CMD_STATE(sc) != FNIC_IOREQ_ABTS_PENDING) {
                        /* This is a late completion. Ignore it */
                        spin_unlock_irqrestore(io_lock, flags);
                        return;
                }
                CMD_STATE(sc) = FNIC_IOREQ_ABTS_COMPLETE;
                CMD_ABTS_STATUS(sc) = hdr_status;

                FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                              "abts cmpl recd. id %d status %s\n",
                              (int)(id & FNIC_TAG_MASK),
                              fnic_fcpio_status_to_str(hdr_status));

                /*
                 * If scsi_eh thread is blocked waiting for abts to complete,
                 * signal completion to it. IO will be cleaned in the thread
                 * else clean it in this context
                 */
                if (io_req->abts_done) {
                        complete(io_req->abts_done);
                        spin_unlock_irqrestore(io_lock, flags);
                } else {
                        FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                                      "abts cmpl, completing IO\n");
                        CMD_SP(sc) = NULL;
                        sc->result = (DID_ERROR << 16);

                        spin_unlock_irqrestore(io_lock, flags);

                        fnic_release_ioreq_buf(fnic, io_req, sc);
                        mempool_free(io_req, fnic->io_req_pool);
                        if (sc->scsi_done)
                                sc->scsi_done(sc);
                }

        } else if (id & FNIC_TAG_DEV_RST) {
                /* Completion of device reset */
                CMD_LR_STATUS(sc) = hdr_status;
                CMD_STATE(sc) = FNIC_IOREQ_CMD_COMPLETE;
                FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                              "dev reset cmpl recd. id %d status %s\n",
                              (int)(id & FNIC_TAG_MASK),
                              fnic_fcpio_status_to_str(hdr_status));
                if (io_req->dr_done)
                        complete(io_req->dr_done);
                spin_unlock_irqrestore(io_lock, flags);

        } else {
                shost_printk(KERN_ERR, fnic->lport->host,
                             "Unexpected itmf io state %s tag %x\n",
                             fnic_ioreq_state_to_str(CMD_STATE(sc)), id);
                spin_unlock_irqrestore(io_lock, flags);
        }

}

/*
 * fnic_fcpio_cmpl_handler
 * Routine to service the cq for wq_copy
 */
static int fnic_fcpio_cmpl_handler(struct vnic_dev *vdev,
                                   unsigned int cq_index,
                                   struct fcpio_fw_req *desc)
{
        struct fnic *fnic = vnic_dev_priv(vdev);
        int ret = 0;

        switch (desc->hdr.type) {
        case FCPIO_ACK: /* fw copied copy wq desc to its queue */
                fnic_fcpio_ack_handler(fnic, cq_index, desc);
                break;

        case FCPIO_ICMND_CMPL: /* fw completed a command */
                fnic_fcpio_icmnd_cmpl_handler(fnic, desc);
                break;

        case FCPIO_ITMF_CMPL: /* fw completed itmf (abort cmd, lun reset)*/
                fnic_fcpio_itmf_cmpl_handler(fnic, desc);
                break;

        case FCPIO_FLOGI_REG_CMPL: /* fw completed flogi_reg */
                ret = fnic_fcpio_flogi_reg_cmpl_handler(fnic, desc);
                break;

        case FCPIO_RESET_CMPL: /* fw completed reset */
                ret = fnic_fcpio_fw_reset_cmpl_handler(fnic, desc);
                break;

        default:
                FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                              "firmware completion type %d\n",
                              desc->hdr.type);
                break;
        }

        return ret;
}

/*
 * fnic_wq_copy_cmpl_handler
 * Routine to process wq copy
 */
int fnic_wq_copy_cmpl_handler(struct fnic *fnic, int copy_work_to_do)
{
        unsigned int wq_work_done = 0;
        unsigned int i, cq_index;
        unsigned int cur_work_done;

        for (i = 0; i < fnic->wq_copy_count; i++) {
                cq_index = i + fnic->raw_wq_count + fnic->rq_count;
                cur_work_done = vnic_cq_copy_service(&fnic->cq[cq_index],
                                                     fnic_fcpio_cmpl_handler,
                                                     copy_work_to_do);
                wq_work_done += cur_work_done;
        }
        return wq_work_done;
}

static void fnic_cleanup_io(struct fnic *fnic, int exclude_id)
{
        unsigned int i;
        struct fnic_io_req *io_req;
        unsigned long flags = 0;
        struct scsi_cmnd *sc;
        spinlock_t *io_lock;

        for (i = 0; i < FNIC_MAX_IO_REQ; i++) {
                if (i == exclude_id)
                        continue;

                sc = scsi_host_find_tag(fnic->lport->host, i);
                if (!sc)
                        continue;

                io_lock = fnic_io_lock_hash(fnic, sc);
                spin_lock_irqsave(io_lock, flags);
                io_req = (struct fnic_io_req *)CMD_SP(sc);
                if (!io_req) {
                        spin_unlock_irqrestore(io_lock, flags);
                        goto cleanup_scsi_cmd;
                }

                CMD_SP(sc) = NULL;

                spin_unlock_irqrestore(io_lock, flags);

                /*
                 * If there is a scsi_cmnd associated with this io_req, then
                 * free the corresponding state
                 */
                fnic_release_ioreq_buf(fnic, io_req, sc);
                mempool_free(io_req, fnic->io_req_pool);

cleanup_scsi_cmd:
                sc->result = DID_TRANSPORT_DISRUPTED << 16;
                FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host, "fnic_cleanup_io:"
                              " DID_TRANSPORT_DISRUPTED\n");

                /* Complete the command to SCSI */
                if (sc->scsi_done)
                        sc->scsi_done(sc);
        }
}

void fnic_wq_copy_cleanup_handler(struct vnic_wq_copy *wq,
                                  struct fcpio_host_req *desc)
{
        u32 id;
        struct fnic *fnic = vnic_dev_priv(wq->vdev);
        struct fnic_io_req *io_req;
        struct scsi_cmnd *sc;
        unsigned long flags;

        spinlock_t *io_lock;

        /* get the tag reference */
        fcpio_tag_id_dec(&desc->hdr.tag, &id);
        id &= FNIC_TAG_MASK;

        if (id >= FNIC_MAX_IO_REQ)
                return;

        sc = scsi_host_find_tag(fnic->lport->host, id);
        if (!sc)
                return;

        io_lock = fnic_io_lock_hash(fnic, sc);
        spin_lock_irqsave(io_lock, flags);

        /* Get the IO context which this desc refers to */
        io_req = (struct fnic_io_req *)CMD_SP(sc);

        /* fnic interrupts are turned off by now */

        if (!io_req) {
                spin_unlock_irqrestore(io_lock, flags);
                goto wq_copy_cleanup_scsi_cmd;
        }

        CMD_SP(sc) = NULL;

        spin_unlock_irqrestore(io_lock, flags);

        fnic_release_ioreq_buf(fnic, io_req, sc);
        mempool_free(io_req, fnic->io_req_pool);

wq_copy_cleanup_scsi_cmd:
        sc->result = DID_NO_CONNECT << 16;
        FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host, "wq_copy_cleanup_handler:"
                      " DID_NO_CONNECT\n");

        if (sc->scsi_done)
                sc->scsi_done(sc);
}

static inline int fnic_queue_abort_io_req(struct fnic *fnic, int tag,
                                          u32 task_req, u8 *fc_lun,
                                          struct fnic_io_req *io_req)
{
        struct vnic_wq_copy *wq = &fnic->wq_copy[0];
        unsigned long flags;

        spin_lock_irqsave(&fnic->wq_copy_lock[0], flags);

        if (vnic_wq_copy_desc_avail(wq) <= fnic->wq_copy_desc_low[0])
                free_wq_copy_descs(fnic, wq);

        if (!vnic_wq_copy_desc_avail(wq)) {
                spin_unlock_irqrestore(&fnic->wq_copy_lock[0], flags);
                return 1;
        }
        fnic_queue_wq_copy_desc_itmf(wq, tag | FNIC_TAG_ABORT,
                                     0, task_req, tag, fc_lun, io_req->port_id,
                                     fnic->config.ra_tov, fnic->config.ed_tov);

        spin_unlock_irqrestore(&fnic->wq_copy_lock[0], flags);
        return 0;
}

void fnic_rport_exch_reset(struct fnic *fnic, u32 port_id)
{
        int tag;
        struct fnic_io_req *io_req;
        spinlock_t *io_lock;
        unsigned long flags;
        struct scsi_cmnd *sc;
        struct scsi_lun fc_lun;
        enum fnic_ioreq_state old_ioreq_state;

        FNIC_SCSI_DBG(KERN_DEBUG,
                      fnic->lport->host,
                      "fnic_rport_reset_exch called portid 0x%06x\n",
                      port_id);

        if (fnic->in_remove)
                return;

        for (tag = 0; tag < FNIC_MAX_IO_REQ; tag++) {
                sc = scsi_host_find_tag(fnic->lport->host, tag);
                if (!sc)
                        continue;

                io_lock = fnic_io_lock_hash(fnic, sc);
                spin_lock_irqsave(io_lock, flags);

                io_req = (struct fnic_io_req *)CMD_SP(sc);

                if (!io_req || io_req->port_id != port_id) {
                        spin_unlock_irqrestore(io_lock, flags);
                        continue;
                }

                /*
                 * Found IO that is still pending with firmware and
                 * belongs to rport that went away
                 */
                if (CMD_STATE(sc) == FNIC_IOREQ_ABTS_PENDING) {
                        spin_unlock_irqrestore(io_lock, flags);
                        continue;
                }
                old_ioreq_state = CMD_STATE(sc);
                CMD_STATE(sc) = FNIC_IOREQ_ABTS_PENDING;
                CMD_ABTS_STATUS(sc) = FCPIO_INVALID_CODE;

                BUG_ON(io_req->abts_done);

                FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                              "fnic_rport_reset_exch: Issuing abts\n");

                spin_unlock_irqrestore(io_lock, flags);

                /* Now queue the abort command to firmware */
                int_to_scsilun(sc->device->lun, &fc_lun);

                if (fnic_queue_abort_io_req(fnic, tag,
                                            FCPIO_ITMF_ABT_TASK_TERM,
                                            fc_lun.scsi_lun, io_req)) {
                        /*
                         * Revert the cmd state back to old state, if
                         * it hasnt changed in between. This cmd will get
                         * aborted later by scsi_eh, or cleaned up during
                         * lun reset
                         */
                        io_lock = fnic_io_lock_hash(fnic, sc);

                        spin_lock_irqsave(io_lock, flags);
                        if (CMD_STATE(sc) == FNIC_IOREQ_ABTS_PENDING)
                                CMD_STATE(sc) = old_ioreq_state;
                        spin_unlock_irqrestore(io_lock, flags);
                }
        }

}

void fnic_terminate_rport_io(struct fc_rport *rport)
{
        int tag;
        struct fnic_io_req *io_req;
        spinlock_t *io_lock;
        unsigned long flags;
        struct scsi_cmnd *sc;
        struct scsi_lun fc_lun;
        struct fc_rport_libfc_priv *rdata = rport->dd_data;
        struct fc_lport *lport = rdata->local_port;
        struct fnic *fnic = lport_priv(lport);
        struct fc_rport *cmd_rport;
        enum fnic_ioreq_state old_ioreq_state;

        FNIC_SCSI_DBG(KERN_DEBUG,
                      fnic->lport->host, "fnic_terminate_rport_io called"
                      " wwpn 0x%llx, wwnn0x%llx, portid 0x%06x\n",
                      rport->port_name, rport->node_name,
                      rport->port_id);

        if (fnic->in_remove)
                return;

        for (tag = 0; tag < FNIC_MAX_IO_REQ; tag++) {
                sc = scsi_host_find_tag(fnic->lport->host, tag);
                if (!sc)
                        continue;

                cmd_rport = starget_to_rport(scsi_target(sc->device));
                if (rport != cmd_rport)
                        continue;

                io_lock = fnic_io_lock_hash(fnic, sc);
                spin_lock_irqsave(io_lock, flags);

                io_req = (struct fnic_io_req *)CMD_SP(sc);

                if (!io_req || rport != cmd_rport) {
                        spin_unlock_irqrestore(io_lock, flags);
                        continue;
                }

                /*
                 * Found IO that is still pending with firmware and
                 * belongs to rport that went away
                 */
                if (CMD_STATE(sc) == FNIC_IOREQ_ABTS_PENDING) {
                        spin_unlock_irqrestore(io_lock, flags);
                        continue;
                }
                old_ioreq_state = CMD_STATE(sc);
                CMD_STATE(sc) = FNIC_IOREQ_ABTS_PENDING;
                CMD_ABTS_STATUS(sc) = FCPIO_INVALID_CODE;

                BUG_ON(io_req->abts_done);

                FNIC_SCSI_DBG(KERN_DEBUG,
                              fnic->lport->host,
                              "fnic_terminate_rport_io: Issuing abts\n");

                spin_unlock_irqrestore(io_lock, flags);

                /* Now queue the abort command to firmware */
                int_to_scsilun(sc->device->lun, &fc_lun);

                if (fnic_queue_abort_io_req(fnic, tag,
                                            FCPIO_ITMF_ABT_TASK_TERM,
                                            fc_lun.scsi_lun, io_req)) {
                        /*
                         * Revert the cmd state back to old state, if
                         * it hasnt changed in between. This cmd will get
                         * aborted later by scsi_eh, or cleaned up during
                         * lun reset
                         */
                        io_lock = fnic_io_lock_hash(fnic, sc);

                        spin_lock_irqsave(io_lock, flags);
                        if (CMD_STATE(sc) == FNIC_IOREQ_ABTS_PENDING)
                                CMD_STATE(sc) = old_ioreq_state;
                        spin_unlock_irqrestore(io_lock, flags);
                }
        }

}

static void fnic_block_error_handler(struct scsi_cmnd *sc)
{
        struct Scsi_Host *shost = sc->device->host;
        struct fc_rport *rport = starget_to_rport(scsi_target(sc->device));
        unsigned long flags;

        spin_lock_irqsave(shost->host_lock, flags);
        while (rport->port_state == FC_PORTSTATE_BLOCKED) {
                spin_unlock_irqrestore(shost->host_lock, flags);
                msleep(1000);
                spin_lock_irqsave(shost->host_lock, flags);
        }
        spin_unlock_irqrestore(shost->host_lock, flags);

}

/*
 * This function is exported to SCSI for sending abort cmnds.
 * A SCSI IO is represented by a io_req in the driver.
 * The ioreq is linked to the SCSI Cmd, thus a link with the ULP's IO.
 */
int fnic_abort_cmd(struct scsi_cmnd *sc)
{
        struct fc_lport *lp;
        struct fnic *fnic;
        struct fnic_io_req *io_req;
        struct fc_rport *rport;
        spinlock_t *io_lock;
        unsigned long flags;
        int ret = SUCCESS;
        u32 task_req;
        struct scsi_lun fc_lun;
        DECLARE_COMPLETION_ONSTACK(tm_done);

        /* Wait for rport to unblock */
        fnic_block_error_handler(sc);

        /* Get local-port, check ready and link up */
        lp = shost_priv(sc->device->host);

        fnic = lport_priv(lp);
        FNIC_SCSI_DBG(KERN_DEBUG,
                      fnic->lport->host,
                      "Abort Cmd called FCID 0x%x, LUN 0x%x TAG %d\n",
                      (starget_to_rport(scsi_target(sc->device)))->port_id,
                      sc->device->lun, sc->request->tag);

        if (lp->state != LPORT_ST_READY || !(lp->link_up)) {
                ret = FAILED;
                goto fnic_abort_cmd_end;
        }

        /*
         * Avoid a race between SCSI issuing the abort and the device
         * completing the command.
         *
         * If the command is already completed by the fw cmpl code,
         * we just return SUCCESS from here. This means that the abort
         * succeeded. In the SCSI ML, since the timeout for command has
         * happened, the completion wont actually complete the command
         * and it will be considered as an aborted command
         *
         * The CMD_SP will not be cleared except while holding io_req_lock.
         */
        io_lock = fnic_io_lock_hash(fnic, sc);
        spin_lock_irqsave(io_lock, flags);
        io_req = (struct fnic_io_req *)CMD_SP(sc);
        if (!io_req) {
                spin_unlock_irqrestore(io_lock, flags);
                goto fnic_abort_cmd_end;
        }

        io_req->abts_done = &tm_done;

        if (CMD_STATE(sc) == FNIC_IOREQ_ABTS_PENDING) {
                spin_unlock_irqrestore(io_lock, flags);
                goto wait_pending;
        }
        /*
         * Command is still pending, need to abort it
         * If the firmware completes the command after this point,
         * the completion wont be done till mid-layer, since abort
         * has already started.
         */
        CMD_STATE(sc) = FNIC_IOREQ_ABTS_PENDING;
        CMD_ABTS_STATUS(sc) = FCPIO_INVALID_CODE;

        spin_unlock_irqrestore(io_lock, flags);

        /*
         * Check readiness of the remote port. If the path to remote
         * port is up, then send abts to the remote port to terminate
         * the IO. Else, just locally terminate the IO in the firmware
         */
        rport = starget_to_rport(scsi_target(sc->device));
        if (fc_remote_port_chkready(rport) == 0)
                task_req = FCPIO_ITMF_ABT_TASK;
        else
                task_req = FCPIO_ITMF_ABT_TASK_TERM;

        /* Now queue the abort command to firmware */
        int_to_scsilun(sc->device->lun, &fc_lun);

        if (fnic_queue_abort_io_req(fnic, sc->request->tag, task_req,
                                    fc_lun.scsi_lun, io_req)) {
                spin_lock_irqsave(io_lock, flags);
                io_req = (struct fnic_io_req *)CMD_SP(sc);
                if (io_req)
                        io_req->abts_done = NULL;
                spin_unlock_irqrestore(io_lock, flags);
                ret = FAILED;
                goto fnic_abort_cmd_end;
        }

        /*
         * We queued an abort IO, wait for its completion.
         * Once the firmware completes the abort command, it will
         * wake up this thread.
         */
 wait_pending:
        wait_for_completion_timeout(&tm_done,
                                    msecs_to_jiffies
                                    (2 * fnic->config.ra_tov +
                                     fnic->config.ed_tov));

        /* Check the abort status */
        spin_lock_irqsave(io_lock, flags);

        io_req = (struct fnic_io_req *)CMD_SP(sc);
        if (!io_req) {
                spin_unlock_irqrestore(io_lock, flags);
                ret = FAILED;
                goto fnic_abort_cmd_end;
        }
        io_req->abts_done = NULL;

        /* fw did not complete abort, timed out */
        if (CMD_STATE(sc) == FNIC_IOREQ_ABTS_PENDING) {
                spin_unlock_irqrestore(io_lock, flags);
                ret = FAILED;
                goto fnic_abort_cmd_end;
        }

        /*
         * firmware completed the abort, check the status,
         * free the io_req irrespective of failure or success
         */
        if (CMD_ABTS_STATUS(sc) != FCPIO_SUCCESS)
                ret = FAILED;

        CMD_SP(sc) = NULL;

        spin_unlock_irqrestore(io_lock, flags);

        fnic_release_ioreq_buf(fnic, io_req, sc);
        mempool_free(io_req, fnic->io_req_pool);

fnic_abort_cmd_end:
        FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                      "Returning from abort cmd %s\n",
                      (ret == SUCCESS) ?
                      "SUCCESS" : "FAILED");
        return ret;
}

static inline int fnic_queue_dr_io_req(struct fnic *fnic,
                                       struct scsi_cmnd *sc,
                                       struct fnic_io_req *io_req)
{
        struct vnic_wq_copy *wq = &fnic->wq_copy[0];
        struct scsi_lun fc_lun;
        int ret = 0;
        unsigned long intr_flags;

        spin_lock_irqsave(&fnic->wq_copy_lock[0], intr_flags);

        if (vnic_wq_copy_desc_avail(wq) <= fnic->wq_copy_desc_low[0])
                free_wq_copy_descs(fnic, wq);

        if (!vnic_wq_copy_desc_avail(wq)) {
                ret = -EAGAIN;
                goto lr_io_req_end;
        }

        /* fill in the lun info */
        int_to_scsilun(sc->device->lun, &fc_lun);

        fnic_queue_wq_copy_desc_itmf(wq, sc->request->tag | FNIC_TAG_DEV_RST,
                                     0, FCPIO_ITMF_LUN_RESET, SCSI_NO_TAG,
                                     fc_lun.scsi_lun, io_req->port_id,
                                     fnic->config.ra_tov, fnic->config.ed_tov);

lr_io_req_end:
        spin_unlock_irqrestore(&fnic->wq_copy_lock[0], intr_flags);

        return ret;
}

/*
 * Clean up any pending aborts on the lun
 * For each outstanding IO on this lun, whose abort is not completed by fw,
 * issue a local abort. Wait for abort to complete. Return 0 if all commands
 * successfully aborted, 1 otherwise
 */
static int fnic_clean_pending_aborts(struct fnic *fnic,
                                     struct scsi_cmnd *lr_sc)
{
        int tag;
        struct fnic_io_req *io_req;
        spinlock_t *io_lock;
        unsigned long flags;
        int ret = 0;
        struct scsi_cmnd *sc;
        struct fc_rport *rport;
        struct scsi_lun fc_lun;
        struct scsi_device *lun_dev = lr_sc->device;
        DECLARE_COMPLETION_ONSTACK(tm_done);

        for (tag = 0; tag < FNIC_MAX_IO_REQ; tag++) {
                sc = scsi_host_find_tag(fnic->lport->host, tag);
                /*
                 * ignore this lun reset cmd or cmds that do not belong to
                 * this lun
                 */
                if (!sc || sc == lr_sc || sc->device != lun_dev)
                        continue;

                io_lock = fnic_io_lock_hash(fnic, sc);
                spin_lock_irqsave(io_lock, flags);

                io_req = (struct fnic_io_req *)CMD_SP(sc);

                if (!io_req || sc->device != lun_dev) {
                        spin_unlock_irqrestore(io_lock, flags);
                        continue;
                }

                /*
                 * Found IO that is still pending with firmware and
                 * belongs to the LUN that we are resetting
                 */
                FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                              "Found IO in %s on lun\n",
                              fnic_ioreq_state_to_str(CMD_STATE(sc)));

                BUG_ON(CMD_STATE(sc) != FNIC_IOREQ_ABTS_PENDING);

                CMD_ABTS_STATUS(sc) = FCPIO_INVALID_CODE;
                io_req->abts_done = &tm_done;
                spin_unlock_irqrestore(io_lock, flags);

                /* Now queue the abort command to firmware */
                int_to_scsilun(sc->device->lun, &fc_lun);
                rport = starget_to_rport(scsi_target(sc->device));

                if (fnic_queue_abort_io_req(fnic, tag,
                                            FCPIO_ITMF_ABT_TASK_TERM,
                                            fc_lun.scsi_lun, io_req)) {
                        spin_lock_irqsave(io_lock, flags);
                        io_req = (struct fnic_io_req *)CMD_SP(sc);
                        if (io_req)
                                io_req->abts_done = NULL;
                        spin_unlock_irqrestore(io_lock, flags);
                        ret = 1;
                        goto clean_pending_aborts_end;
                }

                wait_for_completion_timeout(&tm_done,
                                            msecs_to_jiffies
                                            (fnic->config.ed_tov));

                /* Recheck cmd state to check if it is now aborted */
                spin_lock_irqsave(io_lock, flags);
                io_req = (struct fnic_io_req *)CMD_SP(sc);
                if (!io_req) {
                        spin_unlock_irqrestore(io_lock, flags);
                        ret = 1;
                        goto clean_pending_aborts_end;
                }

                io_req->abts_done = NULL;

                /* if abort is still pending with fw, fail */
                if (CMD_STATE(sc) == FNIC_IOREQ_ABTS_PENDING) {
                        spin_unlock_irqrestore(io_lock, flags);
                        ret = 1;
                        goto clean_pending_aborts_end;
                }
                CMD_SP(sc) = NULL;
                spin_unlock_irqrestore(io_lock, flags);

                fnic_release_ioreq_buf(fnic, io_req, sc);
                mempool_free(io_req, fnic->io_req_pool);
        }

clean_pending_aborts_end:
        return ret;
}

/*
 * SCSI Eh thread issues a Lun Reset when one or more commands on a LUN
 * fail to get aborted. It calls driver's eh_device_reset with a SCSI command
 * on the LUN.
 */
int fnic_device_reset(struct scsi_cmnd *sc)
{
        struct fc_lport *lp;
        struct fnic *fnic;
        struct fnic_io_req *io_req;
        struct fc_rport *rport;
        int status;
        int ret = FAILED;
        spinlock_t *io_lock;
        unsigned long flags;
        DECLARE_COMPLETION_ONSTACK(tm_done);

        /* Wait for rport to unblock */
        fnic_block_error_handler(sc);

        /* Get local-port, check ready and link up */
        lp = shost_priv(sc->device->host);

        fnic = lport_priv(lp);
        FNIC_SCSI_DBG(KERN_DEBUG,
                      fnic->lport->host,
                      "Device reset called FCID 0x%x, LUN 0x%x\n",
                      (starget_to_rport(scsi_target(sc->device)))->port_id,
                      sc->device->lun);


        if (lp->state != LPORT_ST_READY || !(lp->link_up))
                goto fnic_device_reset_end;

        /* Check if remote port up */
        rport = starget_to_rport(scsi_target(sc->device));
        if (fc_remote_port_chkready(rport))
                goto fnic_device_reset_end;

        io_lock = fnic_io_lock_hash(fnic, sc);
        spin_lock_irqsave(io_lock, flags);
        io_req = (struct fnic_io_req *)CMD_SP(sc);

        /*
         * If there is a io_req attached to this command, then use it,
         * else allocate a new one.
         */
        if (!io_req) {
                io_req = mempool_alloc(fnic->io_req_pool, GFP_ATOMIC);
                if (!io_req) {
                        spin_unlock_irqrestore(io_lock, flags);
                        goto fnic_device_reset_end;
                }
                memset(io_req, 0, sizeof(*io_req));
                io_req->port_id = rport->port_id;
                CMD_SP(sc) = (char *)io_req;
        }
        io_req->dr_done = &tm_done;
        CMD_STATE(sc) = FNIC_IOREQ_CMD_PENDING;
        CMD_LR_STATUS(sc) = FCPIO_INVALID_CODE;
        spin_unlock_irqrestore(io_lock, flags);

        FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host, "TAG %d\n",
                      sc->request->tag);

        /*
         * issue the device reset, if enqueue failed, clean up the ioreq
         * and break assoc with scsi cmd
         */
        if (fnic_queue_dr_io_req(fnic, sc, io_req)) {
                spin_lock_irqsave(io_lock, flags);
                io_req = (struct fnic_io_req *)CMD_SP(sc);
                if (io_req)
                        io_req->dr_done = NULL;
                goto fnic_device_reset_clean;
        }

        /*
         * Wait on the local completion for LUN reset.  The io_req may be
         * freed while we wait since we hold no lock.
         */
        wait_for_completion_timeout(&tm_done,
                                    msecs_to_jiffies(FNIC_LUN_RESET_TIMEOUT));

        spin_lock_irqsave(io_lock, flags);
        io_req = (struct fnic_io_req *)CMD_SP(sc);
        if (!io_req) {
                spin_unlock_irqrestore(io_lock, flags);
                goto fnic_device_reset_end;
        }
        io_req->dr_done = NULL;

        status = CMD_LR_STATUS(sc);
        spin_unlock_irqrestore(io_lock, flags);

        /*
         * If lun reset not completed, bail out with failed. io_req
         * gets cleaned up during higher levels of EH
         */
        if (status == FCPIO_INVALID_CODE) {
                FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                              "Device reset timed out\n");
                goto fnic_device_reset_end;
        }

        /* Completed, but not successful, clean up the io_req, return fail */
        if (status != FCPIO_SUCCESS) {
                spin_lock_irqsave(io_lock, flags);
                FNIC_SCSI_DBG(KERN_DEBUG,
                              fnic->lport->host,
                              "Device reset completed - failed\n");
                io_req = (struct fnic_io_req *)CMD_SP(sc);
                goto fnic_device_reset_clean;
        }

        /*
         * Clean up any aborts on this lun that have still not
         * completed. If any of these fail, then LUN reset fails.
         * clean_pending_aborts cleans all cmds on this lun except
         * the lun reset cmd. If all cmds get cleaned, the lun reset
         * succeeds
         */
        if (fnic_clean_pending_aborts(fnic, sc)) {
                spin_lock_irqsave(io_lock, flags);
                io_req = (struct fnic_io_req *)CMD_SP(sc);
                FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                              "Device reset failed"
                              " since could not abort all IOs\n");
                goto fnic_device_reset_clean;
        }

        /* Clean lun reset command */
        spin_lock_irqsave(io_lock, flags);
        io_req = (struct fnic_io_req *)CMD_SP(sc);
        if (io_req)
                /* Completed, and successful */
                ret = SUCCESS;

fnic_device_reset_clean:
        if (io_req)
                CMD_SP(sc) = NULL;

        spin_unlock_irqrestore(io_lock, flags);

        if (io_req) {
                fnic_release_ioreq_buf(fnic, io_req, sc);
                mempool_free(io_req, fnic->io_req_pool);
        }

fnic_device_reset_end:
        FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                      "Returning from device reset %s\n",
                      (ret == SUCCESS) ?
                      "SUCCESS" : "FAILED");
        return ret;
}

/* Clean up all IOs, clean up libFC local port */
int fnic_reset(struct Scsi_Host *shost)
{
        struct fc_lport *lp;
        struct fnic *fnic;
        int ret = SUCCESS;

        lp = shost_priv(shost);
        fnic = lport_priv(lp);

        FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                      "fnic_reset called\n");

        /*
         * Reset local port, this will clean up libFC exchanges,
         * reset remote port sessions, and if link is up, begin flogi
         */
        if (lp->tt.lport_reset(lp))
                ret = FAILED;

        FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                      "Returning from fnic reset %s\n",
                      (ret == SUCCESS) ?
                      "SUCCESS" : "FAILED");

        return ret;
}

/*
 * SCSI Error handling calls driver's eh_host_reset if all prior
 * error handling levels return FAILED. If host reset completes
 * successfully, and if link is up, then Fabric login begins.
 *
 * Host Reset is the highest level of error recovery. If this fails, then
 * host is offlined by SCSI.
 *
 */
int fnic_host_reset(struct scsi_cmnd *sc)
{
        int ret;
        unsigned long wait_host_tmo;
        struct Scsi_Host *shost = sc->device->host;
        struct fc_lport *lp = shost_priv(shost);

        /*
         * If fnic_reset is successful, wait for fabric login to complete
         * scsi-ml tries to send a TUR to every device if host reset is
         * successful, so before returning to scsi, fabric should be up
         */
        ret = fnic_reset(shost);
        if (ret == SUCCESS) {
                wait_host_tmo = jiffies + FNIC_HOST_RESET_SETTLE_TIME * HZ;
                ret = FAILED;
                while (time_before(jiffies, wait_host_tmo)) {
                        if ((lp->state == LPORT_ST_READY) &&
                            (lp->link_up)) {
                                ret = SUCCESS;
                                break;
                        }
                        ssleep(1);
                }
        }

        return ret;
}

/*
 * This fxn is called from libFC when host is removed
 */
void fnic_scsi_abort_io(struct fc_lport *lp)
{
        int err = 0;
        unsigned long flags;
        enum fnic_state old_state;
        struct fnic *fnic = lport_priv(lp);
        DECLARE_COMPLETION_ONSTACK(remove_wait);

        /* Issue firmware reset for fnic, wait for reset to complete */
        spin_lock_irqsave(&fnic->fnic_lock, flags);
        fnic->remove_wait = &remove_wait;
        old_state = fnic->state;
        fnic->state = FNIC_IN_FC_TRANS_ETH_MODE;
        vnic_dev_del_addr(fnic->vdev, fnic->data_src_addr);
        spin_unlock_irqrestore(&fnic->fnic_lock, flags);

        err = fnic_fw_reset_handler(fnic);
        if (err) {
                spin_lock_irqsave(&fnic->fnic_lock, flags);
                if (fnic->state == FNIC_IN_FC_TRANS_ETH_MODE)
                        fnic->state = old_state;
                fnic->remove_wait = NULL;
                spin_unlock_irqrestore(&fnic->fnic_lock, flags);
                return;
        }

        /* Wait for firmware reset to complete */
        wait_for_completion_timeout(&remove_wait,
                                    msecs_to_jiffies(FNIC_RMDEVICE_TIMEOUT));

        spin_lock_irqsave(&fnic->fnic_lock, flags);
        fnic->remove_wait = NULL;
        FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
                      "fnic_scsi_abort_io %s\n",
                      (fnic->state == FNIC_IN_ETH_MODE) ?
                      "SUCCESS" : "FAILED");
        spin_unlock_irqrestore(&fnic->fnic_lock, flags);

}

/*
 * This fxn called from libFC to clean up driver IO state on link down
 */
void fnic_scsi_cleanup(struct fc_lport *lp)
{
        unsigned long flags;
        enum fnic_state old_state;
        struct fnic *fnic = lport_priv(lp);

        /* issue fw reset */
        spin_lock_irqsave(&fnic->fnic_lock, flags);
        old_state = fnic->state;
        fnic->state = FNIC_IN_FC_TRANS_ETH_MODE;
        vnic_dev_del_addr(fnic->vdev, fnic->data_src_addr);
        spin_unlock_irqrestore(&fnic->fnic_lock, flags);

        if (fnic_fw_reset_handler(fnic)) {
                spin_lock_irqsave(&fnic->fnic_lock, flags);
                if (fnic->state == FNIC_IN_FC_TRANS_ETH_MODE)
                        fnic->state = old_state;
                spin_unlock_irqrestore(&fnic->fnic_lock, flags);
        }

}

void fnic_empty_scsi_cleanup(struct fc_lport *lp)
{
}

void fnic_exch_mgr_reset(struct fc_lport *lp, u32 sid, u32 did)
{
        struct fnic *fnic = lport_priv(lp);

        /* Non-zero sid, nothing to do */
        if (sid)
                goto call_fc_exch_mgr_reset;

        if (did) {
                fnic_rport_exch_reset(fnic, did);
                goto call_fc_exch_mgr_reset;
        }

        /*
         * sid = 0, did = 0
         * link down or device being removed
         */
        if (!fnic->in_remove)
                fnic_scsi_cleanup(lp);
        else
                fnic_scsi_abort_io(lp);

        /* call libFC exch mgr reset to reset its exchanges */
call_fc_exch_mgr_reset:
        fc_exch_mgr_reset(lp, sid, did);

}