diff options
Diffstat (limited to 'drivers/scsi/libfc/fc_fcp.c')
| -rw-r--r-- | drivers/scsi/libfc/fc_fcp.c | 2131 |
1 files changed, 2131 insertions, 0 deletions
diff --git a/drivers/scsi/libfc/fc_fcp.c b/drivers/scsi/libfc/fc_fcp.c new file mode 100644 index 000000000000..404e63ff46b8 --- /dev/null +++ b/drivers/scsi/libfc/fc_fcp.c @@ -0,0 +1,2131 @@ +/* + * 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> + +MODULE_AUTHOR("Open-FCoE.org"); +MODULE_DESCRIPTION("libfc"); +MODULE_LICENSE("GPL"); + +static int fc_fcp_debug; + +#define FC_DEBUG_FCP(fmt...) \ + do { \ + if (fc_fcp_debug) \ + FC_DBG(fmt); \ + } while (0) + +static struct kmem_cache *scsi_pkt_cachep; + +/* 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; +} + +/** + * fc_fcp_pkt_release - release hold on scsi_pkt packet + * @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); +} + +/** + * fc_fcp_pkt_destory - release hold on scsi_pkt packet + * + * @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); +} + +/** + * fc_fcp_lock_pkt - lock a packet and get a ref to it. + * @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; + fsp->io_status = SUGGEST_RETRY << 24; + fsp->status_code = FC_ERROR; + fc_fcp_complete_locked(fsp); +} + +/* + * 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); + + if (offset + len > fsp->data_len) { + /* + * this should never happen + */ + if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) && + fc_frame_crc_check(fp)) + goto crc_err; + FC_DEBUG_FCP("data received past end. len %zx offset %zx " + "data_len %x\n", len, offset, fsp->data_len); + 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: + stats = lp->dev_stats[smp_processor_id()]; + stats->ErrorFrames++; + if (stats->InvalidCRCCount++ < 5) + FC_DBG("CRC error on data frame\n"); + /* + * 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); +} + +/* + * fc_fcp_send_data - Send SCSI data to target. + * @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 */ + FC_DEBUG_FCP("xfer-ready past end. seq_blen %zx offset %zx\n", + seq_blen, offset); + fc_fcp_send_abort(fsp); + return 0; + } else if (offset != fsp->xfer_len) { + /* Out of Order Data Request - no problem, but unexpected. */ + FC_DEBUG_FCP("xfer-ready non-contiguous. " + "seq_blen %zx offset %zx\n", seq_blen, offset); + } + + /* + * 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. + */ + t_blen = lp->seq_offload ? seq_blen : fsp->max_payload; + 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); + + /* + * If a get_page()/put_page() will fail, don't use sg lists + * in the fc_frame structure. + * + * The put_page() may be long after the I/O has completed + * in the case of FCoE, since the network driver does it + * via free_skb(). See the test in free_pages_check(). + * + * Test this case with 'dd </dev/zero >/dev/st0 bs=64k'. + */ + if (using_sg) { + for (sg = scsi_sglist(sc); sg; sg = sg_next(sg)) { + if (page_count(sg_page(sg)) == 0 || + (sg_page(sg)->flags & (1 << PG_lru | + 1 << PG_private | + 1 << PG_locked | + 1 << PG_active | + 1 << PG_slab | + 1 << PG_swapcache | + 1 << PG_writeback | + 1 << PG_reserved | + 1 << PG_buddy))) { + using_sg = 0; + break; + } + } + } + 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) { + WARN_ON(skb_shinfo(fp_skb(fp))->nr_frags > + FC_FRAME_SG_LEN); + 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; + + if (tlen) + 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); + } +} + +/* + * fc_fcp_reduce_can_queue - drop can_queue + * @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; + shost_printk(KERN_ERR, lp->host, "Could not allocate frame.\n" + "Reducing can_queue to %d.\n", can_queue); +done: + spin_unlock_irqrestore(lp->host->host_lock, flags); +} + +/* + * exch mgr calls this routine to process scsi + * exchanges. + * + * 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; + struct fc_lport *lp; + 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; + lp = fsp->lp; + + if (!(lp->state & LPORT_ST_READY)) + 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 { + FC_DBG("unexpected frame. r_ctl %x\n", r_ctl); + } +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) + fc_fcp_reduce_can_queue(lp); +} + +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; + + 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; + FC_DBG("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); + } + fc_fcp_complete_locked(fsp); + return; + +len_err: + FC_DBG("short FCP response. flags 0x%x len %u respl %u snsl %u\n", + flags, fr_len(fp), respl, snsl); +err: + fsp->status_code = FC_ERROR; + fc_fcp_complete_locked(fsp); +} + +/** + * fc_fcp_complete_locked - complete processing of a fcp packet + * @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; + fsp->io_status = SUGGEST_RETRY << 24; + } + } + + 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; +} + +/** + * fc_fcp_cleanup_each_cmd - run fn on each active command + * @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); +} + +/** + * fc_fcp_pkt_send - send a fcp packet to the lower level. + * @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); + fr_cmd(fp) = fsp->cmd; + 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) { + fc_frame_free(fp); + 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; + + switch (error) { + case -FC_EX_CLOSED: + fc_fcp_retry_cmd(fsp); + goto unlock; + default: + FC_DBG("unknown error %ld\n", PTR_ERR(fp)); + } + /* + * 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 + */ +static int fc_fcp_pkt_abort(struct fc_lport *lp, struct fc_fcp_pkt *fsp) +{ + 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) { + FC_DBG("target abort cmd failed\n"); + rc = FAILED; + } else if (fsp->state & FC_SRB_ABORTED) { + FC_DBG("target abort cmd passed\n"); + 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) { + FC_DBG("lun reset failed\n"); + return FAILED; + } + + /* cdb_status holds the tmf's rsp code */ + if (fsp->cdb_status != FCP_TMF_CMPL) + return FAILED; + + FC_DBG("lun reset to lun %u completed\n", lun); + 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; + fsp->io_status = SUGGEST_RETRY << 24; + 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); + if (lp->tt.elsct_send(lp, rport, fp, ELS_REC, fc_fcp_rec_resp, + fsp, jiffies_to_msecs(FC_SCSI_REC_TOV))) { + fc_fcp_pkt_hold(fsp); /* hold while REC outstanding */ + return; + } + fc_frame_free(fp); +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: + FC_DEBUG_FCP("device %x unexpected REC reject " + "reason %d expl %d\n", + fsp->rport->port_id, rjt->er_reason, + rjt->er_explan); + /* fall through */ + case ELS_RJT_UNSUP: + FC_DEBUG_FCP("device does not support REC\n"); + 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: + FC_DBG("REC %p fid %x error unexpected error %d\n", + fsp, fsp->rport->port_id, error); + 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. + */ + FC_DBG("REC fid %x error error %d retry %d/%d\n", + fsp->rport->port_id, error, fsp->recov_retry, + FC_MAX_RECOV_RETRY); + 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)); + if (!seq) { + fc_frame_free(fp); + goto retry; + } + 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 ? */ + return (lp->state == LPORT_ST_READY) && (lp->link_status & FC_LINK_UP); +} + +/** + * 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 */ + 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 + */ + stats = lp->dev_stats[smp_processor_id()]; + 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); + +/** + * fc_io_compl - Handle responses for completed commands + * @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; + + 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 if (fsp->cdb_status == QUEUE_FULL) { + struct scsi_device *tmp_sdev; + struct scsi_device *sdev = sc_cmd->device; + + shost_for_each_device(tmp_sdev, sdev->host) { + if (tmp_sdev->id != sdev->id) + continue; + + if (tmp_sdev->queue_depth > 1) { + scsi_track_queue_full(tmp_sdev, + tmp_sdev-> + queue_depth - 1); + } + } + sc_cmd->result = (DID_OK << 16) | fsp->cdb_status; + } 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: + if (fsp->cdb_status == 0) { + /* + * scsi status is good but transport level + * underrun. for read it should be an error?? + */ + sc_cmd->result = (DID_OK << 16) | fsp->cdb_status; + } 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: + sc_cmd->result = (DID_ABORT << 16) | fsp->io_status; + 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); +} + +/** + * fc_fcp_complete - complete processing of a fcp packet + * @fsp: fcp packet + * + * This function may sleep if a fsp timer is pending. + * The host lock must not be held by caller. + */ +void fc_fcp_complete(struct fc_fcp_pkt *fsp) +{ + if (fc_fcp_lock_pkt(fsp)) + return; + + fc_fcp_complete_locked(fsp); + fc_fcp_unlock_pkt(fsp); +} +EXPORT_SYMBOL(fc_fcp_complete); + +/** + * fc_eh_abort - Abort a command...from scsi host template + * @sc_cmd: scsi command to abort + * + * 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; + else if (!(lp->link_status & FC_LINK_UP)) + 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; + } + + rc = fc_fcp_pkt_abort(lp, fsp); + fc_fcp_unlock_pkt(fsp); + +release_pkt: + fc_fcp_pkt_release(fsp); + return rc; +} +EXPORT_SYMBOL(fc_eh_abort); + +/** + * fc_eh_device_reset: Reset a single LUN + * @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; + + fsp = fc_fcp_pkt_alloc(lp, GFP_NOIO); + if (fsp == NULL) { + FC_DBG("could not allocate scsi_pkt\n"); + 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); + +/** + * fc_eh_host_reset - The reset function will reset the ports on the host. + * @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; + + 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)) { + shost_printk(KERN_INFO, shost, "Host reset succeeded.\n"); + return SUCCESS; + } else { + shost_printk(KERN_INFO, shost, "Host reset failed. " + "lport not ready.\n"); + return FAILED; + } +} +EXPORT_SYMBOL(fc_eh_host_reset); + +/** + * fc_slave_alloc - configure queue depth + * @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)); + int queue_depth; + + if (!rport || fc_remote_port_chkready(rport)) + return -ENXIO; + + if (sdev->tagged_supported) { + if (sdev->host->hostt->cmd_per_lun) + queue_depth = sdev->host->hostt->cmd_per_lun; + else + queue_depth = FC_FCP_DFLT_QUEUE_DEPTH; + scsi_activate_tcq(sdev, queue_depth); + } + return 0; +} +EXPORT_SYMBOL(fc_slave_alloc); + +int fc_change_queue_depth(struct scsi_device *sdev, int qdepth) +{ + scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth); + 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)) + printk(KERN_ERR "Leaked scsi packets.\n"); + + mempool_destroy(si->scsi_pkt_pool); + kfree(si); + lp->scsi_priv = NULL; +} +EXPORT_SYMBOL(fc_fcp_destroy); + +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); + +static int __init libfc_init(void) +{ + int rc; + + scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt", + sizeof(struct fc_fcp_pkt), + 0, SLAB_HWCACHE_ALIGN, NULL); + if (scsi_pkt_cachep == NULL) { + FC_DBG("Unable to allocate SRB cache...module load failed!"); + return -ENOMEM; + } + + rc = fc_setup_exch_mgr(); + if (rc) + goto destroy_pkt_cache; + + rc = fc_setup_rport(); + if (rc) + goto destroy_em; + + return rc; +destroy_em: + fc_destroy_exch_mgr(); +destroy_pkt_cache: + kmem_cache_destroy(scsi_pkt_cachep); + return rc; +} + +static void __exit libfc_exit(void) +{ + kmem_cache_destroy(scsi_pkt_cachep); + fc_destroy_exch_mgr(); + fc_destroy_rport(); +} + +module_init(libfc_init); +module_exit(libfc_exit); |