/* * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "fc_libfc.h" 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 acknowledged */ #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_READ (1 << 1) #define FC_SRB_WRITE (1 << 0) /* * The SCp.ptr should be tested and set under the scsi_pkt_queue lock */ #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 - FCP layer internal data * @scsi_pkt_pool: Memory pool to draw FCP packets from * @scsi_queue_lock: Protects the scsi_pkt_queue * @scsi_pkt_queue: Current FCP packets * @last_can_queue_ramp_down_time: ramp down time * @last_can_queue_ramp_up_time: ramp up time * @max_can_queue: max can_queue size */ struct fc_fcp_internal { mempool_t *scsi_pkt_pool; spinlock_t scsi_queue_lock; struct list_head scsi_pkt_queue; unsigned long last_can_queue_ramp_down_time; unsigned long last_can_queue_ramp_up_time; int max_can_queue; }; #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 *, struct fc_frame *); static void fc_fcp_recovery(struct fc_fcp_pkt *, u8 code); static void fc_fcp_timeout(unsigned long); 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_CRC_ERROR 10 #define FC_TIMED_OUT 11 /* * Error recovery timeout values. */ #define FC_SCSI_TM_TOV (10 * HZ) #define FC_HOST_RESET_TIMEOUT (30 * HZ) #define FC_CAN_QUEUE_PERIOD (60 * HZ) #define FC_MAX_ERROR_CNT 5 #define FC_MAX_RECOV_RETRY 3 #define FC_FCP_DFLT_QUEUE_DEPTH 32 /** * fc_fcp_pkt_alloc() - Allocate a fcp_pkt * @lport: The local port that the FCP packet is for * @gfp: GFP flags for allocation * * Return value: fcp_pkt structure or null on allocation failure. * Context: Can be called from process context, no lock is required. */ static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lport, gfp_t gfp) { struct fc_fcp_internal *si = fc_get_scsi_internal(lport); struct fc_fcp_pkt *fsp; fsp = mempool_alloc(si->scsi_pkt_pool, gfp); if (fsp) { memset(fsp, 0, sizeof(*fsp)); fsp->lp = lport; fsp->xfer_ddp = FC_XID_UNKNOWN; atomic_set(&fsp->ref_cnt, 1); init_timer(&fsp->timer); fsp->timer.data = (unsigned long)fsp; INIT_LIST_HEAD(&fsp->list); spin_lock_init(&fsp->scsi_pkt_lock); } return fsp; } /** * fc_fcp_pkt_release() - Release hold on a fcp_pkt * @fsp: The FCP packet to be released * * Context: Can be called from process or interrupt context, * no lock is 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); } } /** * fc_fcp_pkt_hold() - Hold a fcp_pkt * @fsp: The FCP packet to be held */ static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp) { atomic_inc(&fsp->ref_cnt); } /** * fc_fcp_pkt_destory() - Release hold on a fcp_pkt * @seq: The sequence that the FCP packet is on (required by destructor API) * @fsp: The FCP packet to be released * * This routine is called by a destructor callback in the exch_seq_send() * routine of the libfc Transport Template. The 'struct fc_seq' is a required * argument even though it is not used by this routine. * * Context: 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 fcp_pkt and increase its reference count * @fsp: The FCP packet to be locked and incremented * * 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; } /** * fc_fcp_unlock_pkt() - Release a fcp_pkt's lock and decrement its * reference count * @fsp: The FCP packet to be unlocked and decremented */ static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp) { spin_unlock_bh(&fsp->scsi_pkt_lock); fc_fcp_pkt_release(fsp); } /** * fc_fcp_timer_set() - Start a timer for a fcp_pkt * @fsp: The FCP packet to start a timer for * @delay: The timeout period in jiffies */ 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); } /** * fc_fcp_send_abort() - Send an abort for exchanges associated with a * fcp_pkt * @fsp: The FCP packet to abort exchanges on */ 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); } /** * fc_fcp_retry_cmd() - Retry a fcp_pkt * @fsp: The FCP packet to be retried * * Sets the status code to be FC_ERROR and then calls * fc_fcp_complete_locked() which in turn calls fc_io_compl(). * fc_io_compl() will notify the SCSI-ml that the I/O is done. * The SCSI-ml will retry the command. */ 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 = 0; fsp->status_code = FC_ERROR; fc_fcp_complete_locked(fsp); } /** * fc_fcp_ddp_setup() - Calls a LLD's ddp_setup routine to set up DDP context * @fsp: The FCP packet that will manage the DDP frames * @xid: The XID that will be used for the DDP exchange */ void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid) { struct fc_lport *lport; lport = fsp->lp; if ((fsp->req_flags & FC_SRB_READ) && (lport->lro_enabled) && (lport->tt.ddp_setup)) { if (lport->tt.ddp_setup(lport, xid, scsi_sglist(fsp->cmd), scsi_sg_count(fsp->cmd))) fsp->xfer_ddp = xid; } } /** * fc_fcp_ddp_done() - Calls a LLD's ddp_done routine to release any * DDP related resources for a fcp_pkt * @fsp: The FCP packet that DDP had been used on */ void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp) { struct fc_lport *lport; if (!fsp) return; if (fsp->xfer_ddp == FC_XID_UNKNOWN) return; lport = fsp->lp; if (lport->tt.ddp_done) { fsp->xfer_len = lport->tt.ddp_done(lport, fsp->xfer_ddp); fsp->xfer_ddp = FC_XID_UNKNOWN; } } /** * fc_fcp_can_queue_ramp_up() - increases can_queue * @lport: lport to ramp up can_queue */ static void fc_fcp_can_queue_ramp_up(struct fc_lport *lport) { struct fc_fcp_internal *si = fc_get_scsi_internal(lport); unsigned long flags; int can_queue; spin_lock_irqsave(lport->host->host_lock, flags); if (si->last_can_queue_ramp_up_time && (time_before(jiffies, si->last_can_queue_ramp_up_time + FC_CAN_QUEUE_PERIOD))) goto unlock; if (time_before(jiffies, si->last_can_queue_ramp_down_time + FC_CAN_QUEUE_PERIOD)) goto unlock; si->last_can_queue_ramp_up_time = jiffies; can_queue = lport->host->can_queue << 1; if (can_queue >= si->max_can_queue) { can_queue = si->max_can_queue; si->last_can_queue_ramp_down_time = 0; } lport->host->can_queue = can_queue; shost_printk(KERN_ERR, lport->host, "libfc: increased " "can_queue to %d.\n", can_queue); unlock: spin_unlock_irqrestore(lport->host->host_lock, flags); } /** * fc_fcp_can_queue_ramp_down() - reduces can_queue * @lport: lport to reduce can_queue * * 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_can_queue_ramp_down(struct fc_lport *lport) { struct fc_fcp_internal *si = fc_get_scsi_internal(lport); unsigned long flags; int can_queue; spin_lock_irqsave(lport->host->host_lock, flags); if (si->last_can_queue_ramp_down_time && (time_before(jiffies, si->last_can_queue_ramp_down_time + FC_CAN_QUEUE_PERIOD))) goto unlock; si->last_can_queue_ramp_down_time = jiffies; can_queue = lport->host->can_queue; can_queue >>= 1; if (!can_queue) can_queue = 1; lport->host->can_queue = can_queue; shost_printk(KERN_ERR, lport->host, "libfc: Could not allocate frame.\n" "Reducing can_queue to %d.\n", can_queue); unlock: spin_unlock_irqrestore(lport->host->host_lock, flags); } /* * fc_fcp_frame_alloc() - Allocates fc_frame structure and buffer. * @lport: fc lport struct * @len: payload length * * Allocates fc_frame structure and buffer but if fails to allocate * then reduce can_queue. */ static inline struct fc_frame *fc_fcp_frame_alloc(struct fc_lport *lport, size_t len) { struct fc_frame *fp; fp = fc_frame_alloc(lport, len); if (likely(fp)) return fp; /* error case */ fc_fcp_can_queue_ramp_down(lport); return NULL; } /** * fc_fcp_recv_data() - Handler for receiving SCSI-FCP data from a target * @fsp: The FCP packet the data is on * @fp: The data frame */ static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp) { struct scsi_cmnd *sc = fsp->cmd; struct fc_lport *lport = fsp->lp; struct fc_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; u32 nents; u8 host_bcode = FC_COMPLETE; 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 this I/O is ddped then clear it and initiate recovery since data * frames are expected to be placed directly in that case. * * Indicate error to scsi-ml because something went wrong with the * ddp handling to get us here. */ if (fsp->xfer_ddp != FC_XID_UNKNOWN) { fc_fcp_ddp_done(fsp); FC_FCP_DBG(fsp, "DDP I/O in fc_fcp_recv_data set ERROR\n"); host_bcode = FC_ERROR; goto err; } 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_FCP_DBG(fsp, "data received past end. len %zx offset %zx " "data_len %x\n", len, offset, fsp->data_len); /* Data is corrupted indicate scsi-ml should retry */ host_bcode = FC_DATA_OVRRUN; goto err; } if (offset != fsp->xfer_len) fsp->state |= FC_SRB_DISCONTIG; sg = scsi_sglist(sc); nents = scsi_sg_count(sc); if (!(fr_flags(fp) & FCPHF_CRC_UNCHECKED)) { copy_len = fc_copy_buffer_to_sglist(buf, len, sg, &nents, &offset, NULL); } else { crc = crc32(~0, (u8 *) fh, sizeof(*fh)); copy_len = fc_copy_buffer_to_sglist(buf, len, sg, &nents, &offset, &crc); buf = fc_frame_payload_get(fp, 0); if (len % 4) crc = crc32(crc, buf + len, 4 - (len % 4)); if (~crc != le32_to_cpu(fr_crc(fp))) { crc_err: stats = per_cpu_ptr(lport->stats, get_cpu()); stats->ErrorFrames++; /* per cpu count, not total count, but OK for limit */ if (stats->InvalidCRCCount++ < FC_MAX_ERROR_CNT) printk(KERN_WARNING "libfc: CRC error on data " "frame for port (%6.6x)\n", lport->port_id); put_cpu(); /* * 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) { host_bcode = FC_CRC_ERROR; goto err; } 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); return; err: fc_fcp_recovery(fsp, host_bcode); } /** * fc_fcp_send_data() - Send SCSI data to a target * @fsp: The FCP packet the data is on * @sp: The sequence the data is to be sent on * @offset: The starting offset for this data request * @seq_blen: The burst length for this data request * * Called after receiving a Transfer Ready data descriptor. * If the LLD is capable of sequence offload then send down the * seq_blen amount of data in single frame, otherwise send * multiple frames of the maximum frame payload supported by * the target port. */ 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 *lport = fsp->lp; struct page *page; size_t remaining; size_t t_blen; size_t tlen; size_t sg_bytes; size_t frame_offset, fh_parm_offset; size_t off; int error; void *data = NULL; void *page_addr; int using_sg = lport->sg_supp; u32 f_ctl; WARN_ON(seq_blen <= 0); if (unlikely(offset + seq_blen > fsp->data_len)) { /* this should never happen */ FC_FCP_DBG(fsp, "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_FCP_DBG(fsp, "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 = fsp->max_payload; if (lport->seq_offload) { t_blen = min(seq_blen, (size_t)lport->lso_max); FC_FCP_DBG(fsp, "fsp=%p:lso:blen=%zx lso_max=0x%x t_blen=%zx\n", fsp, seq_blen, lport->lso_max, t_blen); } if (t_blen > 512) t_blen &= ~(512 - 1); /* round down to block size */ sc = fsp->cmd; remaining = seq_blen; fh_parm_offset = frame_offset = offset; tlen = 0; seq = lport->tt.seq_start_next(seq); f_ctl = FC_FC_REL_OFF; WARN_ON(!seq); sg = scsi_sglist(sc); while (remaining > 0 && sg) { if (offset >= sg->length) { offset -= sg->length; sg = sg_next(sg); continue; } if (!fp) { tlen = min(t_blen, remaining); /* * TODO. Temporary workaround. fc_seq_send() can't * handle odd lengths in non-linear skbs. * This will be the final fragment only. */ if (tlen % 4) using_sg = 0; fp = fc_frame_alloc(lport, using_sg ? 0 : tlen); if (!fp) return -ENOMEM; data = fc_frame_header_get(fp) + 1; fh_parm_offset = frame_offset; fr_max_payload(fp) = fsp->max_payload; } off = offset + sg->offset; sg_bytes = min(tlen, sg->length - offset); sg_bytes = min(sg_bytes, (size_t) (PAGE_SIZE - (off & ~PAGE_MASK))); page = sg_page(sg) + (off >> PAGE_SHIFT); if (using_sg) { get_page(page); skb_fill_page_desc(fp_skb(fp), skb_shinfo(fp_skb(fp))->nr_frags, page, off & ~PAGE_MASK, sg_bytes); fp_skb(fp)->data_len += sg_bytes; fr_len(fp) += sg_bytes; fp_skb(fp)->truesize += PAGE_SIZE; } else { /* * The scatterlist item may be bigger than PAGE_SIZE, * but we must not cross pages inside the kmap. */ page_addr = kmap_atomic(page); memcpy(data, (char *)page_addr + (off & ~PAGE_MASK), sg_bytes); kunmap_atomic(page_addr); data += sg_bytes; } offset += sg_bytes; frame_offset += sg_bytes; tlen -= sg_bytes; remaining -= sg_bytes; if ((skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN) && (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 = lport->tt.seq_send(lport, seq, fp); if (error) { WARN_ON(1); /* send error should be rare */ return error; } fp = NULL; } fsp->xfer_len += seq_blen; /* premature count? */ return 0; } /** * fc_fcp_abts_resp() - Receive an ABTS response * @fsp: The FCP packet that is being aborted * @fp: The response frame */ 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_recv() - Receive an FCP frame * @seq: The sequence the frame is on * @fp: The received frame * @arg: The related FCP packet * * Context: Called from Soft IRQ context. Can not be called * holding the FCP packet 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 *lport = fsp->lp; struct fc_frame_header *fh; struct fcp_txrdy *dd; u8 r_ctl; int rc = 0; if (IS_ERR(fp)) { fc_fcp_error(fsp, fp); return; } fh = fc_frame_header_get(fp); r_ctl = fh->fh_r_ctl; if (lport->state != LPORT_ST_READY) goto out; if (fc_fcp_lock_pkt(fsp)) goto out; 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 (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_FCP_DBG(fsp, "unexpected frame. r_ctl %x\n", r_ctl); } unlock: fc_fcp_unlock_pkt(fsp); out: fc_frame_free(fp); } /** * fc_fcp_resp() - Handler for FCP responses * @fsp: The FCP packet the response is for * @fp: The response frame */ 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 ddp, update xfer len */ fc_fcp_ddp_done(fsp); 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; } } 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 transferred 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_FCP_DBG(fsp, "tgt %6.6x 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_FCP_DBG(fsp, "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_pkt with the * fcp_pkt lock held * @fsp: The FCP packet to be completed * * 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 *lport = 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 = 0; } } 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 = lport->tt.seq_start_next(seq); conf_frame = fc_fcp_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); lport->tt.seq_send(lport, csp, conf_frame); } } lport->tt.exch_done(seq); } /* * Some resets driven by SCSI are not I/Os and do not have * SCSI commands associated with the requests. We should not * call I/O completion if we do not have a SCSI command. */ if (fsp->cmd) fc_io_compl(fsp); } /** * fc_fcp_cleanup_cmd() - Cancel the active exchange on a fcp_pkt * @fsp: The FCP packet whose exchanges should be canceled * @error: The reason for the cancellation */ static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error) { struct fc_lport *lport = fsp->lp; if (fsp->seq_ptr) { lport->tt.exch_done(fsp->seq_ptr); fsp->seq_ptr = NULL; } fsp->status_code = error; } /** * fc_fcp_cleanup_each_cmd() - Cancel all exchanges on a local port * @lport: The local port whose exchanges should be canceled * @id: The target's ID * @lun: The LUN * @error: The reason for cancellation * * If lun or id is -1, they are ignored. */ static void fc_fcp_cleanup_each_cmd(struct fc_lport *lport, unsigned int id, unsigned int lun, int error) { struct fc_fcp_internal *si = fc_get_scsi_internal(lport); struct fc_fcp_pkt *fsp; struct scsi_cmnd *sc_cmd; unsigned long flags; spin_lock_irqsave(&si->scsi_queue_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(&si->scsi_queue_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(&si->scsi_queue_lock, flags); /* * while we dropped the lock multiple pkts could * have been released, so we have to start over. */ goto restart; } spin_unlock_irqrestore(&si->scsi_queue_lock, flags); } /** * fc_fcp_abort_io() - Abort all FCP-SCSI exchanges on a local port * @lport: The local port whose exchanges are to be aborted */ static void fc_fcp_abort_io(struct fc_lport *lport) { fc_fcp_cleanup_each_cmd(lport, -1, -1, FC_HRD_ERROR); } /** * fc_fcp_pkt_send() - Send a fcp_pkt * @lport: The local port to send the FCP packet on * @fsp: The FCP packet to send * * Return: Zero for success and -1 for failure * Locks: Called without locks held */ static int fc_fcp_pkt_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp) { struct fc_fcp_internal *si = fc_get_scsi_internal(lport); unsigned long flags; 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, &fsp->cdb_cmd.fc_lun); memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len); spin_lock_irqsave(&si->scsi_queue_lock, flags); list_add_tail(&fsp->list, &si->scsi_pkt_queue); spin_unlock_irqrestore(&si->scsi_queue_lock, flags); rc = lport->tt.fcp_cmd_send(lport, fsp, fc_fcp_recv); if (unlikely(rc)) { spin_lock_irqsave(&si->scsi_queue_lock, flags); fsp->cmd->SCp.ptr = NULL; list_del(&fsp->list); spin_unlock_irqrestore(&si->scsi_queue_lock, flags); } return rc; } /** * get_fsp_rec_tov() - Helper function to get REC_TOV * @fsp: the FCP packet * * Returns rec tov in jiffies as rpriv->e_d_tov + 1 second */ static inline unsigned int get_fsp_rec_tov(struct fc_fcp_pkt *fsp) { struct fc_rport_libfc_priv *rpriv = fsp->rport->dd_data; return msecs_to_jiffies(rpriv->e_d_tov) + HZ; } /** * fc_fcp_cmd_send() - Send a FCP command * @lport: The local port to send the command on * @fsp: The FCP packet the command is on * @resp: The handler for the response */ static int fc_fcp_cmd_send(struct fc_lport *lport, 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 *rpriv; const size_t len = sizeof(fsp->cdb_cmd); int rc = 0; if (fc_fcp_lock_pkt(fsp)) return 0; fp = fc_fcp_frame_alloc(lport, sizeof(fsp->cdb_cmd)); if (!fp) { rc = -1; goto unlock; } memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len); fr_fsp(fp) = fsp; rport = fsp->rport; fsp->max_payload = rport->maxframe_size; rpriv = rport->dd_data; fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id, rpriv->local_port->port_id, FC_TYPE_FCP, FC_FCTL_REQ, 0); seq = lport->tt.exch_seq_send(lport, fp, resp, fc_fcp_pkt_destroy, fsp, 0); if (!seq) { rc = -1; goto unlock; } 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); if (rpriv->flags & FC_RP_FLAGS_REC_SUPPORTED) fc_fcp_timer_set(fsp, get_fsp_rec_tov(fsp)); unlock: fc_fcp_unlock_pkt(fsp); return rc; } /** * fc_fcp_error() - Handler for FCP layer errors * @fsp: The FCP packet the error is on * @fp: The frame that has errored */ 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; if (error == -FC_EX_CLOSED) { fc_fcp_retry_cmd(fsp); goto unlock; } /* * 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); } /** * fc_fcp_pkt_abort() - Abort a fcp_pkt * @fsp: The FCP packet to abort on * * Called to send an abort and then wait for abort completion */ static int fc_fcp_pkt_abort(struct fc_fcp_pkt *fsp) { int rc = FAILED; unsigned long ticks_left; 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); ticks_left = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV); spin_lock_bh(&fsp->scsi_pkt_lock); fsp->wait_for_comp = 0; if (!ticks_left) { FC_FCP_DBG(fsp, "target abort cmd failed\n"); } else if (fsp->state & FC_SRB_ABORTED) { FC_FCP_DBG(fsp, "target abort cmd passed\n"); rc = SUCCESS; fc_fcp_complete_locked(fsp); } return rc; } /** * fc_lun_reset_send() - Send LUN reset command * @data: The FCP packet that identifies the LUN to be reset */ static void fc_lun_reset_send(unsigned long data) { struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data; struct fc_lport *lport = fsp->lp; if (lport->tt.fcp_cmd_send(lport, 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, get_fsp_rec_tov(fsp)); fc_fcp_unlock_pkt(fsp); } } /** * fc_lun_reset() - Send a LUN RESET command to a device * and wait for the reply * @lport: The local port to sent the command on * @fsp: The FCP packet that identifies the LUN to be reset * @id: The SCSI command ID * @lun: The LUN ID to be reset */ static int fc_lun_reset(struct fc_lport *lport, 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, &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) { lport->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_SCSI_DBG(lport, "lun reset failed\n"); return FAILED; } /* cdb_status holds the tmf's rsp code */ if (fsp->cdb_status != FCP_TMF_CMPL) return FAILED; FC_SCSI_DBG(lport, "lun reset to lun %u completed\n", lun); fc_fcp_cleanup_each_cmd(lport, id, lun, FC_CMD_ABORTED); return SUCCESS; } /** * fc_tm_done() - Task Management response handler * @seq: The sequence that the response is on * @fp: The response frame * @arg: The FCP packet the response is for */ 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)) goto out; /* * raced with eh timeout handler. */ if (!fsp->seq_ptr || !fsp->wait_for_comp) goto out_unlock; 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); out_unlock: fc_fcp_unlock_pkt(fsp); out: fc_frame_free(fp); } /** * fc_fcp_cleanup() - Cleanup all FCP exchanges on a local port * @lport: The local port to be cleaned up */ static void fc_fcp_cleanup(struct fc_lport *lport) { fc_fcp_cleanup_each_cmd(lport, -1, -1, FC_ERROR); } /** * fc_fcp_timeout() - Handler for fcp_pkt timeouts * @data: The FCP packet that has timed out * * If REC is supported then 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 then 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 *rpriv = 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 (rpriv->flags & FC_RP_FLAGS_REC_SUPPORTED) fc_fcp_rec(fsp); else if (fsp->state & FC_SRB_RCV_STATUS) fc_fcp_complete_locked(fsp); else fc_fcp_recovery(fsp, FC_TIMED_OUT); fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO; unlock: fc_fcp_unlock_pkt(fsp); } /** * fc_fcp_rec() - Send a REC ELS request * @fsp: The FCP packet to send the REC request on */ static void fc_fcp_rec(struct fc_fcp_pkt *fsp) { struct fc_lport *lport; struct fc_frame *fp; struct fc_rport *rport; struct fc_rport_libfc_priv *rpriv; lport = fsp->lp; rport = fsp->rport; rpriv = rport->dd_data; if (!fsp->seq_ptr || rpriv->rp_state != RPORT_ST_READY) { fsp->status_code = FC_HRD_ERROR; fsp->io_status = 0; fc_fcp_complete_locked(fsp); return; } fp = fc_fcp_frame_alloc(lport, 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, rpriv->local_port->port_id, FC_TYPE_ELS, FC_FCTL_REQ, 0); if (lport->tt.elsct_send(lport, rport->port_id, fp, ELS_REC, fc_fcp_rec_resp, fsp, 2 * lport->r_a_tov)) { fc_fcp_pkt_hold(fsp); /* hold while REC outstanding */ return; } retry: if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY) fc_fcp_timer_set(fsp, get_fsp_rec_tov(fsp)); else fc_fcp_recovery(fsp, FC_TIMED_OUT); } /** * fc_fcp_rec_resp() - Handler for REC ELS responses * @seq: The sequence the response is on * @fp: The response frame * @arg: The FCP packet the response is on * * If the response is a reject then the scsi layer will handle * the timeout. If the response is a LS_ACC then if the I/O was not completed * set the timeout and return. If the I/O was completed then complete the * exchange and tell the SCSI layer. */ 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 *rpriv; 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_FCP_DBG(fsp, "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_FCP_DBG(fsp, "device does not support REC\n"); rpriv = fsp->rport->dd_data; /* * if we do not spport RECs or got some bogus * reason then resetup timer so we check for * making progress. */ rpriv->flags &= ~FC_RP_FLAGS_REC_SUPPORTED; 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_fcp_recovery(fsp, FC_ERROR); 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, get_fsp_rec_tov(fsp)); } 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); } /** * fc_fcp_rec_error() - Handler for REC errors * @fsp: The FCP packet the error is on * @fp: The REC frame */ 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_FCP_DBG(fsp, "REC %p fid %6.6x 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_FCP_DBG(fsp, "REC fid %6.6x 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_fcp_recovery(fsp, FC_ERROR); break; } fc_fcp_unlock_pkt(fsp); out: fc_fcp_pkt_release(fsp); /* drop hold for outstanding REC */ } /** * fc_fcp_recovery() - Handler for fcp_pkt recovery * @fsp: The FCP pkt that needs to be aborted */ static void fc_fcp_recovery(struct fc_fcp_pkt *fsp, u8 code) { fsp->status_code = code; 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); } /** * fc_fcp_srr() - Send a SRR request (Sequence Retransmission Request) * @fsp: The FCP packet the SRR is to be sent on * @r_ctl: The R_CTL field for the SRR 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 *lport = fsp->lp; struct fc_rport *rport; struct fc_rport_libfc_priv *rpriv; struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr); struct fc_seq *seq; struct fcp_srr *srr; struct fc_frame *fp; unsigned int rec_tov; rport = fsp->rport; rpriv = rport->dd_data; if (!(rpriv->flags & FC_RP_FLAGS_RETRY) || rpriv->rp_state != RPORT_ST_READY) goto retry; /* shouldn't happen */ fp = fc_fcp_frame_alloc(lport, 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, rpriv->local_port->port_id, FC_TYPE_FCP, FC_FCTL_REQ, 0); rec_tov = get_fsp_rec_tov(fsp); seq = lport->tt.exch_seq_send(lport, fp, fc_fcp_srr_resp, fc_fcp_pkt_destroy, fsp, jiffies_to_msecs(rec_tov)); if (!seq) 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); } /** * fc_fcp_srr_resp() - Handler for SRR response * @seq: The sequence the SRR is on * @fp: The SRR frame * @arg: The FCP packet the SRR is on */ 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; } switch (fc_frame_payload_op(fp)) { case ELS_LS_ACC: fsp->recov_retry = 0; fc_fcp_timer_set(fsp, get_fsp_rec_tov(fsp)); break; case ELS_LS_RJT: default: fc_fcp_recovery(fsp, FC_ERROR); break; } fc_fcp_unlock_pkt(fsp); out: fsp->lp->tt.exch_done(seq); fc_frame_free(fp); } /** * fc_fcp_srr_error() - Handler for SRR errors * @fsp: The FCP packet that the SRR error is on * @fp: The SRR frame */ static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp) { if (fc_fcp_lock_pkt(fsp)) goto out; switch (PTR_ERR(fp)) { case -FC_EX_TIMEOUT: if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY) fc_fcp_rec(fsp); else fc_fcp_recovery(fsp, FC_TIMED_OUT); break; case -FC_EX_CLOSED: /* e.g., link failure */ /* fall through */ default: fc_fcp_retry_cmd(fsp); break; } fc_fcp_unlock_pkt(fsp); out: fsp->lp->tt.exch_done(fsp->recov_seq); } /** * fc_fcp_lport_queue_ready() - Determine if the lport and it's queue is ready * @lport: The local port to be checked */ static inline int fc_fcp_lport_queue_ready(struct fc_lport *lport) { /* lock ? */ return (lport->state == LPORT_ST_READY) && lport->link_up && !lport->qfull; } /** * fc_queuecommand() - The queuecommand function of the SCSI template * @shost: The Scsi_Host that the command was issued to * @cmd: The scsi_cmnd to be executed * * This is the i/o strategy routine, called by the SCSI layer. */ int fc_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *sc_cmd) { struct fc_lport *lport = shost_priv(shost); struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device)); struct fc_fcp_pkt *fsp; struct fc_rport_libfc_priv *rpriv; int rval; int rc = 0; struct fc_stats *stats; rval = fc_remote_port_chkready(rport); if (rval) { sc_cmd->result = rval; sc_cmd->scsi_done(sc_cmd); return 0; } if (!*(struct fc_remote_port **)rport->dd_data) { /* * rport is transitioning from blocked/deleted to * online */ sc_cmd->result = DID_IMM_RETRY << 16; sc_cmd->scsi_done(sc_cmd); goto out; } rpriv = rport->dd_data; if (!fc_fcp_lport_queue_ready(lport)) { if (lport->qfull) fc_fcp_can_queue_ramp_down(lport); rc = SCSI_MLQUEUE_HOST_BUSY; goto out; } fsp = fc_fcp_pkt_alloc(lport, 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->rport = rport; /* set the remote port ptr */ /* * set up the transfer length */ fsp->data_len = scsi_bufflen(sc_cmd); fsp->xfer_len = 0; /* * setup the data direction */ stats = per_cpu_ptr(lport->stats, get_cpu()); if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) { fsp->req_flags = FC_SRB_READ; stats->InputRequests++; stats->InputBytes += fsp->data_len; } else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) { fsp->req_flags = FC_SRB_WRITE; stats->OutputRequests++; stats->OutputBytes += fsp->data_len; } else { fsp->req_flags = 0; stats->ControlRequests++; } put_cpu(); /* * send it to the lower layer * if we get -1 return then put the request in the pending * queue. */ rval = fc_fcp_pkt_send(lport, 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: The FCP packet that is complete * * Translates fcp_pkt errors to a Linux SCSI errors. * 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 *lport; unsigned long flags; /* release outstanding ddp context */ fc_fcp_ddp_done(fsp); 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); } lport = fsp->lp; si = fc_get_scsi_internal(lport); /* * if can_queue ramp down is done then try can_queue ramp up * since commands are completing now. */ if (si->last_can_queue_ramp_down_time) fc_fcp_can_queue_ramp_up(lport); sc_cmd = fsp->cmd; CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status; switch (fsp->status_code) { case FC_COMPLETE: if (fsp->cdb_status == 0) { /* * good I/O status */ sc_cmd->result = DID_OK << 16; if (fsp->scsi_resid) CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid; } else { /* * transport level I/O was ok but scsi * has non zero status */ sc_cmd->result = (DID_OK << 16) | fsp->cdb_status; } break; case FC_ERROR: FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml " "due to FC_ERROR\n"); sc_cmd->result = DID_ERROR << 16; break; case FC_DATA_UNDRUN: if ((fsp->cdb_status == 0) && !(fsp->req_flags & FC_SRB_READ)) { /* * scsi status is good but transport level * underrun. */ if (fsp->state & FC_SRB_RCV_STATUS) { sc_cmd->result = DID_OK << 16; } else { FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml" " due to FC_DATA_UNDRUN (trans)\n"); sc_cmd->result = DID_ERROR << 16; } } else { /* * scsi got underrun, this is an error */ FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml " "due to FC_DATA_UNDRUN (scsi)\n"); 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 */ FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml " "due to FC_DATA_OVRRUN\n"); sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status; break; case FC_CMD_ABORTED: FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml " "due to FC_CMD_ABORTED\n"); sc_cmd->result = (DID_ERROR << 16) | fsp->io_status; break; case FC_CMD_RESET: FC_FCP_DBG(fsp, "Returning DID_RESET to scsi-ml " "due to FC_CMD_RESET\n"); sc_cmd->result = (DID_RESET << 16); break; case FC_HRD_ERROR: FC_FCP_DBG(fsp, "Returning DID_NO_CONNECT to scsi-ml " "due to FC_HRD_ERROR\n"); sc_cmd->result = (DID_NO_CONNECT << 16); break; case FC_CRC_ERROR: FC_FCP_DBG(fsp, "Returning DID_PARITY to scsi-ml " "due to FC_CRC_ERROR\n"); sc_cmd->result = (DID_PARITY << 16); break; case FC_TIMED_OUT: FC_FCP_DBG(fsp, "Returning DID_BUS_BUSY to scsi-ml " "due to FC_TIMED_OUT\n"); sc_cmd->result = (DID_BUS_BUSY << 16) | fsp->io_status; break; default: FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml " "due to unknown error\n"); sc_cmd->result = (DID_ERROR << 16); break; } if (lport->state != LPORT_ST_READY && fsp->status_code != FC_COMPLETE) sc_cmd->result = (DID_TRANSPORT_DISRUPTED << 16); spin_lock_irqsave(&si->scsi_queue_lock, flags); list_del(&fsp->list); sc_cmd->SCp.ptr = NULL; spin_unlock_irqrestore(&si->scsi_queue_lock, flags); sc_cmd->scsi_done(sc_cmd); /* release ref from initial allocation in queue command */ fc_fcp_pkt_release(fsp); } /** * fc_eh_abort() - Abort a command * @sc_cmd: The SCSI command to abort * * From SCSI host template. * Send an ABTS to the target device and wait for the response. */ int fc_eh_abort(struct scsi_cmnd *sc_cmd) { struct fc_fcp_pkt *fsp; struct fc_lport *lport; struct fc_fcp_internal *si; int rc = FAILED; unsigned long flags; int rval; rval = fc_block_scsi_eh(sc_cmd); if (rval) return rval; lport = shost_priv(sc_cmd->device->host); if (lport->state != LPORT_ST_READY) return rc; else if (!lport->link_up) return rc; si = fc_get_scsi_internal(lport); spin_lock_irqsave(&si->scsi_queue_lock, flags); fsp = CMD_SP(sc_cmd); if (!fsp) { /* command completed while scsi eh was setting up */ spin_unlock_irqrestore(&si->scsi_queue_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(&si->scsi_queue_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(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: The SCSI command which identifies the device whose * LUN is to be reset * * Set from SCSI host template. */ int fc_eh_device_reset(struct scsi_cmnd *sc_cmd) { struct fc_lport *lport; struct fc_fcp_pkt *fsp; struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device)); int rc = FAILED; int rval; rval = fc_block_scsi_eh(sc_cmd); if (rval) return rval; lport = shost_priv(sc_cmd->device->host); if (lport->state != LPORT_ST_READY) return rc; FC_SCSI_DBG(lport, "Resetting rport (%6.6x)\n", rport->port_id); fsp = fc_fcp_pkt_alloc(lport, GFP_NOIO); if (fsp == NULL) { printk(KERN_WARNING "libfc: could not allocate scsi_pkt\n"); 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->rport = rport; /* set the remote port ptr */ /* * flush outstanding commands */ rc = fc_lun_reset(lport, 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() - Reset a Scsi_Host. * @sc_cmd: The SCSI command that identifies the SCSI host to be reset */ int fc_eh_host_reset(struct scsi_cmnd *sc_cmd) { struct Scsi_Host *shost = sc_cmd->device->host; struct fc_lport *lport = shost_priv(shost); unsigned long wait_tmo; FC_SCSI_DBG(lport, "Resetting host\n"); fc_block_scsi_eh(sc_cmd); lport->tt.lport_reset(lport); wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT; while (!fc_fcp_lport_queue_ready(lport) && time_before(jiffies, wait_tmo)) msleep(1000); if (fc_fcp_lport_queue_ready(lport)) { shost_printk(KERN_INFO, shost, "libfc: Host reset succeeded " "on port (%6.6x)\n", lport->port_id); return SUCCESS; } else { shost_printk(KERN_INFO, shost, "libfc: Host reset failed, " "port (%6.6x) is not ready.\n", lport->port_id); return FAILED; } } EXPORT_SYMBOL(fc_eh_host_reset); /** * fc_slave_alloc() - Configure the queue depth of a Scsi_Host * @sdev: The SCSI device that identifies the SCSI host * * Configures queue depth based on host's cmd_per_len. If not set * then we use the libfc default. */ int fc_slave_alloc(struct scsi_device *sdev) { struct fc_rport *rport = starget_to_rport(scsi_target(sdev)); if (!rport || fc_remote_port_chkready(rport)) return -ENXIO; if (sdev->tagged_supported) scsi_activate_tcq(sdev, FC_FCP_DFLT_QUEUE_DEPTH); else scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), FC_FCP_DFLT_QUEUE_DEPTH); return 0; } EXPORT_SYMBOL(fc_slave_alloc); /** * fc_change_queue_depth() - Change a device's queue depth * @sdev: The SCSI device whose queue depth is to change * @qdepth: The new queue depth * @reason: The resason for the change */ int fc_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason) { switch (reason) { case SCSI_QDEPTH_DEFAULT: scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth); break; case SCSI_QDEPTH_QFULL: scsi_track_queue_full(sdev, qdepth); break; case SCSI_QDEPTH_RAMP_UP: scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth); break; default: return -EOPNOTSUPP; } return sdev->queue_depth; } EXPORT_SYMBOL(fc_change_queue_depth); /** * fc_change_queue_type() - Change a device's queue type * @sdev: The SCSI device whose queue depth is to change * @tag_type: Identifier for queue type */ 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); /** * fc_fcp_destory() - Tear down the FCP layer for a given local port * @lport: The local port that no longer needs the FCP layer */ void fc_fcp_destroy(struct fc_lport *lport) { struct fc_fcp_internal *si = fc_get_scsi_internal(lport); if (!list_empty(&si->scsi_pkt_queue)) printk(KERN_ERR "libfc: Leaked SCSI packets when destroying " "port (%6.6x)\n", lport->port_id); mempool_destroy(si->scsi_pkt_pool); kfree(si); lport->scsi_priv = NULL; } EXPORT_SYMBOL(fc_fcp_destroy); int fc_setup_fcp(void) { int rc = 0; scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt", sizeof(struct fc_fcp_pkt), 0, SLAB_HWCACHE_ALIGN, NULL); if (!scsi_pkt_cachep) { printk(KERN_ERR "libfc: Unable to allocate SRB cache, " "module load failed!"); rc = -ENOMEM; } return rc; } void fc_destroy_fcp(void) { if (scsi_pkt_cachep) kmem_cache_destroy(scsi_pkt_cachep); } /** * fc_fcp_init() - Initialize the FCP layer for a local port * @lport: The local port to initialize the exchange layer for */ int fc_fcp_init(struct fc_lport *lport) { int rc; struct fc_fcp_internal *si; if (!lport->tt.fcp_cmd_send) lport->tt.fcp_cmd_send = fc_fcp_cmd_send; if (!lport->tt.fcp_cleanup) lport->tt.fcp_cleanup = fc_fcp_cleanup; if (!lport->tt.fcp_abort_io) lport->tt.fcp_abort_io = fc_fcp_abort_io; si = kzalloc(sizeof(struct fc_fcp_internal), GFP_KERNEL); if (!si) return -ENOMEM; lport->scsi_priv = si; si->max_can_queue = lport->host->can_queue; INIT_LIST_HEAD(&si->scsi_pkt_queue); spin_lock_init(&si->scsi_queue_lock); 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);