diff options
Diffstat (limited to 'drivers/scsi/libfc/fc_fcp.c')
| -rw-r--r-- | drivers/scsi/libfc/fc_fcp.c | 2339 |
1 files changed, 2339 insertions, 0 deletions
diff --git a/drivers/scsi/libfc/fc_fcp.c b/drivers/scsi/libfc/fc_fcp.c new file mode 100644 index 000000000..4fae253d4 --- /dev/null +++ b/drivers/scsi/libfc/fc_fcp.c @@ -0,0 +1,2339 @@ +/* + * 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 <linux/slab.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> + +#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(struct timer_list *); +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 +#define FC_TRANS_RESET 12 + +/* + * 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; + refcount_set(&fsp->ref_cnt, 1); + timer_setup(&fsp->timer, NULL, 0); + INIT_LIST_HEAD(&fsp->list); + spin_lock_init(&fsp->scsi_pkt_lock); + } else { + per_cpu_ptr(lport->stats, get_cpu())->FcpPktAllocFails++; + put_cpu(); + } + 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 (refcount_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) +{ + refcount_inc(&fsp->ref_cnt); +} + +/** + * fc_fcp_pkt_destroy() - 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 fc_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); + fsp->timer_delay = delay; + } +} + +static void fc_fcp_abort_done(struct fc_fcp_pkt *fsp) +{ + 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_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) +{ + int rc; + + if (!fsp->seq_ptr) + return -EINVAL; + + per_cpu_ptr(fsp->lp->stats, get_cpu())->FcpPktAborts++; + put_cpu(); + + fsp->state |= FC_SRB_ABORT_PENDING; + rc = fc_seq_exch_abort(fsp->seq_ptr, 0); + /* + * fc_seq_exch_abort() might return -ENXIO if + * the sequence is already completed + */ + if (rc == -ENXIO) { + fc_fcp_abort_done(fsp); + rc = 0; + } + return rc; +} + +/** + * 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, int status_code) +{ + if (fsp->seq_ptr) { + fc_exch_done(fsp->seq_ptr); + fsp->seq_ptr = NULL; + } + + fsp->state &= ~FC_SRB_ABORT_PENDING; + fsp->io_status = 0; + fsp->status_code = status_code; + 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 bool 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; + bool changed = false; + + 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; + changed = true; + +unlock: + spin_unlock_irqrestore(lport->host->host_lock, flags); + return changed; +} + +/* + * 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; + + per_cpu_ptr(lport->stats, get_cpu())->FcpFrameAllocFails++; + put_cpu(); + /* error case */ + fc_fcp_can_queue_ramp_down(lport); + shost_printk(KERN_ERR, lport->host, + "libfc: Could not allocate frame, " + "reducing can_queue to %d.\n", lport->host->can_queue); + return NULL; +} + +/** + * 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; + unsigned int e_d_tov = FC_DEF_E_D_TOV; + + if (rpriv && rpriv->e_d_tov > e_d_tov) + e_d_tov = rpriv->e_d_tov; + return msecs_to_jiffies(e_d_tov) + HZ; +} + +/** + * 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_DBG( fsp, "complete out-of-order sequence\n" ); + 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 = fc_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 = fc_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) + fc_fcp_abort_done(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) { + FC_FCP_DBG(fsp, "lport state %d, ignoring r_ctl %x\n", + lport->state, r_ctl); + 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)) { + FC_FCP_DBG(fsp, "command aborted, ignoring r_ctl %x\n", r_ctl); + 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 != FCP_RESP_RSP_INFO_LEN4) && + (respl != FCP_RESP_RSP_INFO_LEN8)) + 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->cdb_status == SAM_STAT_GOOD && + 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. + */ + if (fsp->lp->qfull) { + FC_FCP_DBG(fsp, "tgt %6.6x queue busy retry\n", + fsp->rport->port_id); + return; + } + FC_FCP_DBG(fsp, "tgt %6.6x xfer len %zx data underrun " + "len %x, data len %x\n", + fsp->rport->port_id, + fsp->xfer_len, expected_len, fsp->data_len); + fc_fcp_timer_set(fsp, get_fsp_rec_tov(fsp)); + 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->cdb_status == SAM_STAT_GOOD && + 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)) { + FC_FCP_DBG(fsp, "data underrun, xfer %zx data %x\n", + fsp->xfer_len, fsp->data_len); + fsp->status_code = FC_DATA_UNDRUN; + } + } + + 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 = fc_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); + fc_seq_send(lport, csp, conf_frame); + } + } + fc_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) +{ + if (fsp->seq_ptr) { + fc_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); + + spin_lock_bh(&fsp->scsi_pkt_lock); + if (!(fsp->state & FC_SRB_COMPL)) { + fsp->state |= FC_SRB_COMPL; + /* + * TODO: dropping scsi_pkt_lock and then reacquiring + * again around fc_fcp_cleanup_cmd() is required, + * since fc_fcp_cleanup_cmd() calls into + * fc_seq_set_resp() and that func preempts cpu using + * schedule. May be schedule and related code should be + * removed instead of unlocking here to avoid scheduling + * while atomic bug. + */ + spin_unlock_bh(&fsp->scsi_pkt_lock); + + fc_fcp_cleanup_cmd(fsp, error); + + spin_lock_bh(&fsp->scsi_pkt_lock); + fc_io_compl(fsp); + } + spin_unlock_bh(&fsp->scsi_pkt_lock); + + 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; +} + +/** + * 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 = fc_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 */ + + fsp->timer.function = fc_fcp_timeout; + 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, FC_ERROR); + 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; + + FC_FCP_DBG(fsp, "pkt abort state %x\n", fsp->state); + if (fc_fcp_send_abort(fsp)) { + FC_FCP_DBG(fsp, "failed to send abort\n"); + return FAILED; + } + + if (fsp->state & FC_SRB_ABORTED) { + FC_FCP_DBG(fsp, "target abort cmd completed\n"); + return SUCCESS; + } + + 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(struct timer_list *t) +{ + struct fc_fcp_pkt *fsp = from_timer(fsp, t, timer); + 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; + fsp->timer.function = fc_lun_reset_send; + 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(&fsp->timer); + + /* + * 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) { + fc_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; + fc_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(struct timer_list *t) +{ + struct fc_fcp_pkt *fsp = from_timer(fsp, t, timer); + 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; + + if (fsp->lp->qfull) { + FC_FCP_DBG(fsp, "fcp timeout, resetting timer delay %d\n", + fsp->timer_delay); + fsp->timer.function = fc_fcp_timeout; + fc_fcp_timer_set(fsp, fsp->timer_delay); + goto unlock; + } + FC_FCP_DBG(fsp, "fcp timeout, delay %d flags %x state %x\n", + fsp->timer_delay, rpriv->flags, fsp->state); + 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 invalid REC reject %d/%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: + FC_FCP_DBG(fsp, "device %x REC reject %d/%d\n", + fsp->rport->port_id, rjt->er_reason, + rjt->er_explan); + /* + * If response got lost or is stuck in the + * queue somewhere we have no idea if and when + * the response will be received. So quarantine + * the xid and retry the command. + */ + if (rjt->er_explan == ELS_EXPL_OXID_RXID) { + struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr); + ep->state |= FC_EX_QUARANTINE; + fsp->state |= FC_SRB_ABORTED; + fc_fcp_retry_cmd(fsp, FC_TRANS_RESET); + break; + } + fc_fcp_recovery(fsp, FC_TRANS_RESET); + 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_DBG(fsp, "REC %p fid %6.6x exchange closed\n", + fsp, fsp->rport->port_id); + fc_fcp_retry_cmd(fsp, FC_ERROR); + 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 %p fid %6.6x exchange timeout retry %d/%d\n", + fsp, fsp->rport->port_id, 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) +{ + FC_FCP_DBG(fsp, "start recovery code %x\n", 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; + + 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); + + seq = fc_exch_seq_send(lport, fp, fc_fcp_srr_resp, + fc_fcp_pkt_destroy, + fsp, get_fsp_rec_tov(fsp)); + 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_TRANS_RESET); +} + +/** + * 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 fc_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 fc_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: + fc_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: + FC_FCP_DBG(fsp, "SRR timeout, retries %d\n", fsp->recov_retry); + 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 */ + FC_FCP_DBG(fsp, "SRR error, exchange closed\n"); + /* fall through */ + default: + fc_fcp_retry_cmd(fsp, FC_ERROR); + break; + } + fc_fcp_unlock_pkt(fsp); +out: + fc_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) { + if (fc_fcp_can_queue_ramp_down(lport)) + shost_printk(KERN_ERR, lport->host, + "libfc: queue full, " + "reducing can_queue to %d.\n", + lport->host->can_queue); + } + 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: + if (host_byte(sc_cmd->result) == DID_TIME_OUT) + FC_FCP_DBG(fsp, "Returning DID_TIME_OUT to scsi-ml " + "due to FC_CMD_ABORTED\n"); + else { + FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml " + "due to FC_CMD_ABORTED\n"); + set_host_byte(sc_cmd, DID_ERROR); + } + sc_cmd->result |= 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_TRANS_RESET: + FC_FCP_DBG(fsp, "Returning DID_SOFT_ERROR to scsi-ml " + "due to FC_TRANS_RESET\n"); + sc_cmd->result = (DID_SOFT_ERROR << 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 released 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_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; + + scsi_change_queue_depth(sdev, FC_FCP_DFLT_QUEUE_DEPTH); + return 0; +} +EXPORT_SYMBOL(fc_slave_alloc); + +/** + * 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); |