diff options
Diffstat (limited to 'drivers/scsi/libfc/fc_fcp.c')
| -rw-r--r-- | drivers/scsi/libfc/fc_fcp.c | 1044 |
1 files changed, 552 insertions, 492 deletions
diff --git a/drivers/scsi/libfc/fc_fcp.c b/drivers/scsi/libfc/fc_fcp.c index 59a4408b27b5..c4b58d042f6f 100644 --- a/drivers/scsi/libfc/fc_fcp.c +++ b/drivers/scsi/libfc/fc_fcp.c @@ -39,15 +39,9 @@ #include <scsi/libfc.h> #include <scsi/fc_encode.h> -MODULE_AUTHOR("Open-FCoE.org"); -MODULE_DESCRIPTION("libfc"); -MODULE_LICENSE("GPL v2"); +#include "fc_libfc.h" -unsigned int fc_debug_logging; -module_param_named(debug_logging, fc_debug_logging, int, S_IRUGO|S_IWUSR); -MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels"); - -static struct kmem_cache *scsi_pkt_cachep; +struct kmem_cache *scsi_pkt_cachep; /* SRB state definitions */ #define FC_SRB_FREE 0 /* cmd is free */ @@ -58,7 +52,6 @@ static struct kmem_cache *scsi_pkt_cachep; #define FC_SRB_DISCONTIG (1 << 4) /* non-sequential data recvd */ #define FC_SRB_COMPL (1 << 5) /* fc_io_compl has been run */ #define FC_SRB_FCP_PROCESSING_TMO (1 << 6) /* timer function processing */ -#define FC_SRB_NOMEM (1 << 7) /* dropped to out of mem */ #define FC_SRB_READ (1 << 1) #define FC_SRB_WRITE (1 << 0) @@ -73,10 +66,20 @@ static struct kmem_cache *scsi_pkt_cachep; #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_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; + mempool_t *scsi_pkt_pool; struct list_head scsi_pkt_queue; - u8 throttled; + 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) @@ -90,9 +93,9 @@ static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *); static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *); static void fc_fcp_complete_locked(struct fc_fcp_pkt *); static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *); -static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp); +static void fc_fcp_error(struct fc_fcp_pkt *, struct fc_frame *); static void fc_timeout_error(struct fc_fcp_pkt *); -static void fc_fcp_timeout(unsigned long data); +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 *); @@ -124,6 +127,7 @@ static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *); #define FC_SCSI_TM_TOV (10 * HZ) #define FC_SCSI_REC_TOV (2 * 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 @@ -131,23 +135,22 @@ static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *); #define FC_FCP_DFLT_QUEUE_DEPTH 32 /** - * fc_fcp_pkt_alloc - allocation routine for scsi_pkt packet - * @lp: fc lport struct - * @gfp: gfp flags for allocation + * fc_fcp_pkt_alloc() - Allocate a fcp_pkt + * @lport: The local port that the FCP packet is for + * @gfp: GFP flags for allocation * - * This is used by upper layer scsi driver. - * Return Value : scsi_pkt structure or null on allocation failure. - * Context : call from process context. no locking required. + * 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 *lp, gfp_t gfp) +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(lp); + 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 = lp; + fsp->lp = lport; atomic_set(&fsp->ref_cnt, 1); init_timer(&fsp->timer); INIT_LIST_HEAD(&fsp->list); @@ -157,12 +160,11 @@ static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lp, gfp_t gfp) } /** - * fc_fcp_pkt_release() - release hold on scsi_pkt packet - * @fsp: fcp packet struct + * fc_fcp_pkt_release() - Release hold on a fcp_pkt + * @fsp: The FCP packet to be released * - * This is used by upper layer scsi driver. - * Context : call from process and interrupt context. - * no locking required + * Context: Can be called from process or interrupt context, + * no lock is required. */ static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp) { @@ -173,20 +175,25 @@ static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp) } } +/** + * 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 scsi_pkt packet - * @seq: exchange sequence - * @fsp: fcp packet struct + * 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. * - * Release hold on scsi_pkt packet set to keep scsi_pkt - * till EM layer exch resource is not freed. - * Context : called from from EM layer. - * no locking required + * Context: No locking required. */ static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp) { @@ -194,10 +201,10 @@ static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp) } /** - * fc_fcp_lock_pkt() - lock a packet and get a ref to it. - * @fsp: fcp packet + * 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 + * 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. @@ -222,18 +229,33 @@ static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *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 for the timer + */ 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) @@ -243,9 +265,14 @@ static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp) return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0); } -/* - * Retry command. - * An abort isn't needed. +/** + * 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) { @@ -260,64 +287,146 @@ static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp) fc_fcp_complete_locked(fsp); } -/* - * fc_fcp_ddp_setup - calls to LLD's ddp_setup to set up DDP - * transfer for a read I/O indicated by the fc_fcp_pkt. - * @fsp: ptr to the fc_fcp_pkt - * - * This is called in exch_seq_send() when we have a newly allocated - * exchange with a valid exchange id to setup ddp. - * - * returns: none +/** + * 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 *lp; + struct fc_lport *lport; if (!fsp) return; - lp = fsp->lp; + lport = fsp->lp; if ((fsp->req_flags & FC_SRB_READ) && - (lp->lro_enabled) && (lp->tt.ddp_setup)) { - if (lp->tt.ddp_setup(lp, xid, scsi_sglist(fsp->cmd), - scsi_sg_count(fsp->cmd))) + (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; } } -EXPORT_SYMBOL(fc_fcp_ddp_setup); -/* - * fc_fcp_ddp_done - calls to LLD's ddp_done to release any - * DDP related resources for this I/O if it is initialized - * as a ddp transfer - * @fsp: ptr to the fc_fcp_pkt - * - * returns: none +/** + * 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 */ static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp) { - struct fc_lport *lp; + struct fc_lport *lport; if (!fsp) return; - lp = fsp->lp; - if (fsp->xfer_ddp && lp->tt.ddp_done) { - fsp->xfer_len = lp->tt.ddp_done(lp, fsp->xfer_ddp); - fsp->xfer_ddp = 0; + 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 + * + * Locking notes: Called with Scsi_Host lock held + */ +static void fc_fcp_can_queue_ramp_up(struct fc_lport *lport) +{ + struct fc_fcp_internal *si = fc_get_scsi_internal(lport); + int can_queue; + + if (si->last_can_queue_ramp_up_time && + (time_before(jiffies, si->last_can_queue_ramp_up_time + + FC_CAN_QUEUE_PERIOD))) + return; + + if (time_before(jiffies, si->last_can_queue_ramp_down_time + + FC_CAN_QUEUE_PERIOD)) + return; + + 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); +} + +/** + * 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. + * + * Locking notes: Called with Scsi_Host lock held + */ +static void fc_fcp_can_queue_ramp_down(struct fc_lport *lport) +{ + struct fc_fcp_internal *si = fc_get_scsi_internal(lport); + int can_queue; + + if (si->last_can_queue_ramp_down_time && + (time_before(jiffies, si->last_can_queue_ramp_down_time + + FC_CAN_QUEUE_PERIOD))) + return; + + 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); +} /* - * Receive SCSI data from target. - * Called after receiving solicited data. + * 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; + unsigned long flags; + + fp = fc_frame_alloc(lport, len); + if (!fp) { + spin_lock_irqsave(lport->host->host_lock, flags); + fc_fcp_can_queue_ramp_down(lport); + spin_unlock_irqrestore(lport->host->host_lock, flags); + } + return fp; +} + +/** + * 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 *lp = fsp->lp; + struct fc_lport *lport = fsp->lp; struct fcoe_dev_stats *stats; struct fc_frame_header *fh; size_t start_offset; @@ -327,7 +436,7 @@ static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp) size_t len; void *buf; struct scatterlist *sg; - size_t remaining; + u32 nents; fh = fc_frame_header_get(fp); offset = ntohl(fh->fh_parm_offset); @@ -351,65 +460,29 @@ static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp) if (offset != fsp->xfer_len) fsp->state |= FC_SRB_DISCONTIG; - crc = 0; - if (fr_flags(fp) & FCPHF_CRC_UNCHECKED) - crc = crc32(~0, (u8 *) fh, sizeof(*fh)); - sg = scsi_sglist(sc); - remaining = len; - - while (remaining > 0 && sg) { - size_t off; - void *page_addr; - size_t sg_bytes; + nents = scsi_sg_count(sc); - if (offset >= sg->length) { - offset -= sg->length; - sg = sg_next(sg); - continue; - } - sg_bytes = min(remaining, sg->length - offset); - - /* - * The scatterlist item may be bigger than PAGE_SIZE, - * but we are limited to mapping PAGE_SIZE at a time. - */ - off = offset + sg->offset; - sg_bytes = min(sg_bytes, (size_t) - (PAGE_SIZE - (off & ~PAGE_MASK))); - page_addr = kmap_atomic(sg_page(sg) + (off >> PAGE_SHIFT), - KM_SOFTIRQ0); - if (!page_addr) - break; /* XXX panic? */ - - if (fr_flags(fp) & FCPHF_CRC_UNCHECKED) - crc = crc32(crc, buf, sg_bytes); - memcpy((char *)page_addr + (off & ~PAGE_MASK), buf, - sg_bytes); - - kunmap_atomic(page_addr, KM_SOFTIRQ0); - buf += sg_bytes; - offset += sg_bytes; - remaining -= sg_bytes; - copy_len += sg_bytes; - } - - if (fr_flags(fp) & FCPHF_CRC_UNCHECKED) { + if (!(fr_flags(fp) & FCPHF_CRC_UNCHECKED)) { + copy_len = fc_copy_buffer_to_sglist(buf, len, sg, &nents, + &offset, KM_SOFTIRQ0, NULL); + } else { + crc = crc32(~0, (u8 *) fh, sizeof(*fh)); + copy_len = fc_copy_buffer_to_sglist(buf, len, sg, &nents, + &offset, KM_SOFTIRQ0, &crc); buf = fc_frame_payload_get(fp, 0); - if (len % 4) { + if (len % 4) crc = crc32(crc, buf + len, 4 - (len % 4)); - len += 4 - (len % 4); - } if (~crc != le32_to_cpu(fr_crc(fp))) { crc_err: - stats = fc_lport_get_stats(lp); + stats = fc_lport_get_stats(lport); stats->ErrorFrames++; /* FIXME - per cpu count, not total count! */ if (stats->InvalidCRCCount++ < 5) printk(KERN_WARNING "libfc: CRC error on data " "frame for port (%6x)\n", - fc_host_port_id(lp->host)); + fc_host_port_id(lport->host)); /* * Assume the frame is total garbage. * We may have copied it over the good part @@ -437,18 +510,17 @@ crc_err: } /** - * fc_fcp_send_data() - Send SCSI data to target. - * @fsp: ptr to fc_fcp_pkt - * @sp: ptr to this sequence - * @offset: starting offset for this data request - * @seq_blen: the burst length for this data request + * 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 LLD is capable of seq offload then send down seq_blen - * size of data in single frame, otherwise send multiple FC - * frames of max FC frame payload supported by target port. - * - * Returns : 0 for success. + * If the LLD is capable of sequence offload then send down the + * seq_blen ammount 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) @@ -457,16 +529,18 @@ static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq, struct scsi_cmnd *sc; struct scatterlist *sg; struct fc_frame *fp = NULL; - struct fc_lport *lp = fsp->lp; + 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 = lp->sg_supp; + int using_sg = lport->sg_supp; u32 f_ctl; WARN_ON(seq_blen <= 0); @@ -488,10 +562,10 @@ static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq, * to max FC frame payload previously set in fsp->max_payload. */ t_blen = fsp->max_payload; - if (lp->seq_offload) { - t_blen = min(seq_blen, (size_t)lp->lso_max); + 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, lp->lso_max, t_blen); + fsp, seq_blen, lport->lso_max, t_blen); } WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD); @@ -503,7 +577,7 @@ static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq, remaining = seq_blen; fh_parm_offset = frame_offset = offset; tlen = 0; - seq = lp->tt.seq_start_next(seq); + seq = lport->tt.seq_start_next(seq); f_ctl = FC_FC_REL_OFF; WARN_ON(!seq); @@ -525,43 +599,34 @@ static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq, */ if (tlen % 4) using_sg = 0; - if (using_sg) { - fp = _fc_frame_alloc(lp, 0); - if (!fp) - return -ENOMEM; - } else { - fp = fc_frame_alloc(lp, tlen); - if (!fp) - return -ENOMEM; + fp = fc_frame_alloc(lport, using_sg ? 0 : tlen); + if (!fp) + return -ENOMEM; - data = (void *)(fr_hdr(fp)) + - sizeof(struct fc_frame_header); - } + 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(sg_page(sg)); + get_page(page); skb_fill_page_desc(fp_skb(fp), skb_shinfo(fp_skb(fp))->nr_frags, - sg_page(sg), sg->offset + offset, - sg_bytes); + 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 { - size_t off = offset + sg->offset; - /* * The scatterlist item may be bigger than PAGE_SIZE, * but we must not cross pages inside the kmap. */ - sg_bytes = min(sg_bytes, (size_t) (PAGE_SIZE - - (off & ~PAGE_MASK))); - page_addr = kmap_atomic(sg_page(sg) + - (off >> PAGE_SHIFT), - KM_SOFTIRQ0); + page_addr = kmap_atomic(page, KM_SOFTIRQ0); memcpy(data, (char *)page_addr + (off & ~PAGE_MASK), sg_bytes); kunmap_atomic(page_addr, KM_SOFTIRQ0); @@ -572,7 +637,8 @@ static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq, tlen -= sg_bytes; remaining -= sg_bytes; - if (tlen) + if ((skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN) && + (tlen)) continue; /* @@ -589,7 +655,7 @@ static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq, /* * send fragment using for a sequence. */ - error = lp->tt.seq_send(lp, seq, fp); + error = lport->tt.seq_send(lport, seq, fp); if (error) { WARN_ON(1); /* send error should be rare */ fc_fcp_retry_cmd(fsp); @@ -601,6 +667,11 @@ static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq, return 0; } +/** + * fc_fcp_abts_resp() - Send 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; @@ -637,46 +708,13 @@ static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp) } /** - * fc_fcp_reduce_can_queue() - drop can_queue - * @lp: lport to drop queueing for - * - * If we are getting memory allocation failures, then we may - * be trying to execute too many commands. We let the running - * commands complete or timeout, then try again with a reduced - * can_queue. Eventually we will hit the point where we run - * on all reserved structs. - */ -static void fc_fcp_reduce_can_queue(struct fc_lport *lp) -{ - struct fc_fcp_internal *si = fc_get_scsi_internal(lp); - unsigned long flags; - int can_queue; - - spin_lock_irqsave(lp->host->host_lock, flags); - if (si->throttled) - goto done; - si->throttled = 1; - - can_queue = lp->host->can_queue; - can_queue >>= 1; - if (!can_queue) - can_queue = 1; - lp->host->can_queue = can_queue; - shost_printk(KERN_ERR, lp->host, "libfc: Could not allocate frame.\n" - "Reducing can_queue to %d.\n", can_queue); -done: - spin_unlock_irqrestore(lp->host->host_lock, flags); -} - -/** - * fc_fcp_recv() - Reveive FCP frames + * fc_fcp_recv() - Reveive an FCP frame * @seq: The sequence the frame is on - * @fp: The FC frame + * @fp: The received frame * @arg: The related FCP packet * - * Return : None - * Context : called from Soft IRQ context - * can not called holding list lock + * 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) { @@ -687,8 +725,10 @@ static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg) u8 r_ctl; int rc = 0; - if (IS_ERR(fp)) - goto errout; + if (IS_ERR(fp)) { + fc_fcp_error(fsp, fp); + return; + } fh = fc_frame_header_get(fp); r_ctl = fh->fh_r_ctl; @@ -721,8 +761,6 @@ static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg) (size_t) ntohl(dd->ft_burst_len)); if (!rc) seq->rec_data = fsp->xfer_len; - else if (rc == -ENOMEM) - fsp->state |= FC_SRB_NOMEM; } else if (r_ctl == FC_RCTL_DD_SOL_DATA) { /* * received a DATA frame @@ -742,13 +780,13 @@ unlock: fc_fcp_unlock_pkt(fsp); out: fc_frame_free(fp); -errout: - if (IS_ERR(fp)) - fc_fcp_error(fsp, fp); - else if (rc == -ENOMEM) - fc_fcp_reduce_can_queue(lport); } +/** + * 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; @@ -862,15 +900,16 @@ err: } /** - * fc_fcp_complete_locked() - complete processing of a fcp packet - * @fsp: fcp packet + * 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 *lp = fsp->lp; + struct fc_lport *lport = fsp->lp; struct fc_seq *seq; struct fc_exch *ep; u32 f_ctl; @@ -901,8 +940,8 @@ static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp) struct fc_frame *conf_frame; struct fc_seq *csp; - csp = lp->tt.seq_start_next(seq); - conf_frame = fc_frame_alloc(fsp->lp, 0); + 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; @@ -910,43 +949,48 @@ static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp) fc_fill_fc_hdr(conf_frame, FC_RCTL_DD_SOL_CTL, ep->did, ep->sid, FC_TYPE_FCP, f_ctl, 0); - lp->tt.seq_send(lp, csp, conf_frame); + lport->tt.seq_send(lport, csp, conf_frame); } } - lp->tt.exch_done(seq); + lport->tt.exch_done(seq); } 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 *lp = fsp->lp; + struct fc_lport *lport = fsp->lp; if (fsp->seq_ptr) { - lp->tt.exch_done(fsp->seq_ptr); + lport->tt.exch_done(fsp->seq_ptr); fsp->seq_ptr = NULL; } fsp->status_code = error; } /** - * fc_fcp_cleanup_each_cmd() - Cleanup active commads - * @lp: logical port - * @id: target id - * @lun: lun - * @error: fsp status code + * 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 *lp, unsigned int id, +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(lp); + 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(lp->host->host_lock, flags); + spin_lock_irqsave(lport->host->host_lock, flags); restart: list_for_each_entry(fsp, &si->scsi_pkt_queue, list) { sc_cmd = fsp->cmd; @@ -957,7 +1001,7 @@ restart: continue; fc_fcp_pkt_hold(fsp); - spin_unlock_irqrestore(lp->host->host_lock, flags); + spin_unlock_irqrestore(lport->host->host_lock, flags); if (!fc_fcp_lock_pkt(fsp)) { fc_fcp_cleanup_cmd(fsp, error); @@ -966,35 +1010,36 @@ restart: } fc_fcp_pkt_release(fsp); - spin_lock_irqsave(lp->host->host_lock, flags); + spin_lock_irqsave(lport->host->host_lock, flags); /* * while we dropped the lock multiple pkts could * have been released, so we have to start over. */ goto restart; } - spin_unlock_irqrestore(lp->host->host_lock, flags); + spin_unlock_irqrestore(lport->host->host_lock, flags); } -static void fc_fcp_abort_io(struct fc_lport *lp) +/** + * 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(lp, -1, -1, FC_HRD_ERROR); + fc_fcp_cleanup_each_cmd(lport, -1, -1, FC_HRD_ERROR); } /** - * fc_fcp_pkt_send() - send a fcp packet to the lower level. - * @lp: fc lport - * @fsp: fc packet. + * fc_fcp_pkt_send() - Send a fcp_pkt + * @lport: The local port to send the FCP packet on + * @fsp: The FCP packet to send * - * This is called by upper layer protocol. - * Return : zero for success and -1 for failure - * Context : called from queuecommand which can be called from process - * or scsi soft irq. - * Locks : called with the host lock and irqs disabled. + * Return: Zero for success and -1 for failure + * Locks: Called with the host lock and irqs disabled. */ -static int fc_fcp_pkt_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp) +static int fc_fcp_pkt_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp) { - struct fc_fcp_internal *si = fc_get_scsi_internal(lp); + struct fc_fcp_internal *si = fc_get_scsi_internal(lport); int rc; fsp->cmd->SCp.ptr = (char *)fsp; @@ -1006,16 +1051,22 @@ static int fc_fcp_pkt_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp) memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len); list_add_tail(&fsp->list, &si->scsi_pkt_queue); - spin_unlock_irq(lp->host->host_lock); - rc = lp->tt.fcp_cmd_send(lp, fsp, fc_fcp_recv); - spin_lock_irq(lp->host->host_lock); + spin_unlock_irq(lport->host->host_lock); + rc = lport->tt.fcp_cmd_send(lport, fsp, fc_fcp_recv); + spin_lock_irq(lport->host->host_lock); if (rc) list_del(&fsp->list); return rc; } -static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp, +/** + * 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)) @@ -1023,14 +1074,14 @@ static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp, struct fc_frame *fp; struct fc_seq *seq; struct fc_rport *rport; - struct fc_rport_libfc_priv *rp; + 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_frame_alloc(lp, sizeof(fsp->cdb_cmd)); + fp = fc_fcp_frame_alloc(lport, sizeof(fsp->cdb_cmd)); if (!fp) { rc = -1; goto unlock; @@ -1040,15 +1091,15 @@ static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp, fr_fsp(fp) = fsp; rport = fsp->rport; fsp->max_payload = rport->maxframe_size; - rp = rport->dd_data; + rpriv = rport->dd_data; fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id, - fc_host_port_id(rp->local_port->host), FC_TYPE_FCP, + fc_host_port_id(rpriv->local_port->host), FC_TYPE_FCP, FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0); - seq = lp->tt.exch_seq_send(lp, fp, resp, fc_fcp_pkt_destroy, fsp, 0); + seq = lport->tt.exch_seq_send(lport, fp, resp, fc_fcp_pkt_destroy, + fsp, 0); if (!seq) { - fc_frame_free(fp); rc = -1; goto unlock; } @@ -1065,8 +1116,10 @@ unlock: return rc; } -/* - * transport error handler +/** + * 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) { @@ -1091,11 +1144,13 @@ unlock: fc_fcp_unlock_pkt(fsp); } -/* - * Scsi abort handler- calls to send an abort - * and then wait for abort completion +/** + * 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_lport *lp, struct fc_fcp_pkt *fsp) +static int fc_fcp_pkt_abort(struct fc_fcp_pkt *fsp) { int rc = FAILED; @@ -1122,14 +1177,15 @@ static int fc_fcp_pkt_abort(struct fc_lport *lp, struct fc_fcp_pkt *fsp) return rc; } -/* - * Retry LUN reset after resource allocation failed. +/** + * 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 *lp = fsp->lp; - if (lp->tt.fcp_cmd_send(lp, fsp, fc_tm_done)) { + 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)) @@ -1140,11 +1196,15 @@ static void fc_lun_reset_send(unsigned long data) } } -/* - * Scsi device reset handler- send a LUN RESET to the device - * and wait for reset reply +/** + * fc_lun_reset() - Send a LUN RESET command to a device + * and wait for the reply + * @lport: The local port to sent the comand 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 *lp, struct fc_fcp_pkt *fsp, +static int fc_lun_reset(struct fc_lport *lport, struct fc_fcp_pkt *fsp, unsigned int id, unsigned int lun) { int rc; @@ -1172,14 +1232,14 @@ static int fc_lun_reset(struct fc_lport *lp, struct fc_fcp_pkt *fsp, spin_lock_bh(&fsp->scsi_pkt_lock); if (fsp->seq_ptr) { - lp->tt.exch_done(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(lp, "lun reset failed\n"); + FC_SCSI_DBG(lport, "lun reset failed\n"); return FAILED; } @@ -1187,13 +1247,16 @@ static int fc_lun_reset(struct fc_lport *lp, struct fc_fcp_pkt *fsp, if (fsp->cdb_status != FCP_TMF_CMPL) return FAILED; - FC_SCSI_DBG(lp, "lun reset to lun %u completed\n", lun); - fc_fcp_cleanup_each_cmd(lp, id, lun, FC_CMD_ABORTED); + 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; } -/* - * Task Managment response handler +/** + * fc_tm_done() - Task Managment 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) { @@ -1230,34 +1293,31 @@ static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg) fc_fcp_unlock_pkt(fsp); } -static void fc_fcp_cleanup(struct fc_lport *lp) +/** + * 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(lp, -1, -1, FC_ERROR); + fc_fcp_cleanup_each_cmd(lport, -1, -1, FC_ERROR); } -/* - * fc_fcp_timeout: called by OS timer function. - * - * The timer has been inactivated and must be reactivated if desired - * using fc_fcp_timer_set(). - * - * Algorithm: - * - * If REC is supported, just issue it, and return. The REC exchange will - * complete or time out, and recovery can continue at that point. - * - * Otherwise, if the response has been received without all the data, - * it has been ER_TIMEOUT since the response was received. +/** + * fc_fcp_timeout() - Handler for fcp_pkt timeouts + * @data: The FCP packet that has timed out * - * If the response has not been received, - * we see if data was received recently. If it has been, we continue waiting, - * otherwise, we abort the command. + * 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 *rp = rport->dd_data; + struct fc_rport_libfc_priv *rpriv = rport->dd_data; if (fc_fcp_lock_pkt(fsp)) return; @@ -1267,7 +1327,7 @@ static void fc_fcp_timeout(unsigned long data) fsp->state |= FC_SRB_FCP_PROCESSING_TMO; - if (rp->flags & FC_RP_FLAGS_REC_SUPPORTED) + if (rpriv->flags & FC_RP_FLAGS_REC_SUPPORTED) fc_fcp_rec(fsp); else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2), jiffies)) @@ -1281,39 +1341,40 @@ unlock: fc_fcp_unlock_pkt(fsp); } -/* - * Send a REC ELS request +/** + * 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 *lp; + struct fc_lport *lport; struct fc_frame *fp; struct fc_rport *rport; - struct fc_rport_libfc_priv *rp; + struct fc_rport_libfc_priv *rpriv; - lp = fsp->lp; + lport = fsp->lp; rport = fsp->rport; - rp = rport->dd_data; - if (!fsp->seq_ptr || rp->rp_state != RPORT_ST_READY) { + 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_frame_alloc(lp, sizeof(struct fc_els_rec)); + 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, - fc_host_port_id(rp->local_port->host), FC_TYPE_ELS, + fc_host_port_id(rpriv->local_port->host), FC_TYPE_ELS, FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0); - if (lp->tt.elsct_send(lp, rport->port_id, fp, ELS_REC, fc_fcp_rec_resp, - fsp, jiffies_to_msecs(FC_SCSI_REC_TOV))) { + if (lport->tt.elsct_send(lport, rport->port_id, fp, ELS_REC, + fc_fcp_rec_resp, fsp, + jiffies_to_msecs(FC_SCSI_REC_TOV))) { fc_fcp_pkt_hold(fsp); /* hold while REC outstanding */ return; } - fc_frame_free(fp); retry: if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY) fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV); @@ -1321,12 +1382,16 @@ retry: fc_timeout_error(fsp); } -/* - * Receive handler for REC ELS frame - * if it is a reject then let the scsi layer to handle - * the timeout. if it is a LS_ACC then if the io was not completed - * then set the timeout and return otherwise complete the exchange - * and tell the scsi layer to restart the I/O. +/** + * 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) { @@ -1338,7 +1403,7 @@ static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg) u32 offset; enum dma_data_direction data_dir; enum fc_rctl r_ctl; - struct fc_rport_libfc_priv *rp; + struct fc_rport_libfc_priv *rpriv; if (IS_ERR(fp)) { fc_fcp_rec_error(fsp, fp); @@ -1361,13 +1426,13 @@ static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg) /* fall through */ case ELS_RJT_UNSUP: FC_FCP_DBG(fsp, "device does not support REC\n"); - rp = fsp->rport->dd_data; + 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. */ - rp->flags &= ~FC_RP_FLAGS_REC_SUPPORTED; + rpriv->flags &= ~FC_RP_FLAGS_REC_SUPPORTED; fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT); break; case ELS_RJT_LOGIC: @@ -1464,8 +1529,10 @@ out: fc_frame_free(fp); } -/* - * Handle error response or timeout for REC exchange. +/** + * 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) { @@ -1504,10 +1571,9 @@ out: fc_fcp_pkt_release(fsp); /* drop hold for outstanding REC */ } -/* - * Time out error routine: - * abort's the I/O close the exchange and - * send completion notification to scsi layer +/** + * fc_timeout_error() - Handler for fcp_pkt timeouts + * @fsp: The FCP packt that has timed out */ static void fc_timeout_error(struct fc_fcp_pkt *fsp) { @@ -1521,16 +1587,18 @@ static void fc_timeout_error(struct fc_fcp_pkt *fsp) fc_fcp_send_abort(fsp); } -/* - * Sequence retransmission request. +/** + * 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 *lp = fsp->lp; + struct fc_lport *lport = fsp->lp; struct fc_rport *rport; - struct fc_rport_libfc_priv *rp; + struct fc_rport_libfc_priv *rpriv; struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr); struct fc_seq *seq; struct fcp_srr *srr; @@ -1538,12 +1606,13 @@ static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset) u8 cdb_op; rport = fsp->rport; - rp = rport->dd_data; + rpriv = rport->dd_data; cdb_op = fsp->cdb_cmd.fc_cdb[0]; - if (!(rp->flags & FC_RP_FLAGS_RETRY) || rp->rp_state != RPORT_ST_READY) + if (!(rpriv->flags & FC_RP_FLAGS_RETRY) || + rpriv->rp_state != RPORT_ST_READY) goto retry; /* shouldn't happen */ - fp = fc_frame_alloc(lp, sizeof(*srr)); + fp = fc_fcp_frame_alloc(lport, sizeof(*srr)); if (!fp) goto retry; @@ -1556,15 +1625,14 @@ static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset) srr->srr_rel_off = htonl(offset); fc_fill_fc_hdr(fp, FC_RCTL_ELS4_REQ, rport->port_id, - fc_host_port_id(rp->local_port->host), FC_TYPE_FCP, + fc_host_port_id(rpriv->local_port->host), FC_TYPE_FCP, FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0); - seq = lp->tt.exch_seq_send(lp, fp, fc_fcp_srr_resp, NULL, - fsp, jiffies_to_msecs(FC_SCSI_REC_TOV)); - if (!seq) { - fc_frame_free(fp); + seq = lport->tt.exch_seq_send(lport, fp, fc_fcp_srr_resp, NULL, + fsp, jiffies_to_msecs(FC_SCSI_REC_TOV)); + if (!seq) goto retry; - } + fsp->recov_seq = seq; fsp->xfer_len = offset; fsp->xfer_contig_end = offset; @@ -1575,8 +1643,11 @@ retry: fc_fcp_retry_cmd(fsp); } -/* - * Handle response from SRR. +/** + * 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) { @@ -1622,6 +1693,11 @@ out: fc_fcp_pkt_release(fsp); /* drop hold for outstanding SRR */ } +/** + * 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)) @@ -1646,31 +1722,36 @@ out: fc_fcp_pkt_release(fsp); /* drop hold for outstanding SRR */ } -static inline int fc_fcp_lport_queue_ready(struct fc_lport *lp) +/** + * 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 (lp->state == LPORT_ST_READY) && lp->link_up && !lp->qfull; + return (lport->state == LPORT_ST_READY) && + lport->link_up && !lport->qfull; } /** - * fc_queuecommand - The queuecommand function of the scsi template - * @cmd: struct scsi_cmnd to be executed - * @done: Callback function to be called when cmd is completed + * fc_queuecommand() - The queuecommand function of the SCSI template + * @cmd: The scsi_cmnd to be executed + * @done: The callback function to be called when the scsi_cmnd is complete * - * this is the i/o strategy routine, called by the scsi layer - * this routine is called with holding the host_lock. + * This is the i/o strategy routine, called by the SCSI layer. This routine + * is called with the host_lock held. */ int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *)) { - struct fc_lport *lp; + struct fc_lport *lport; struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device)); struct fc_fcp_pkt *fsp; - struct fc_rport_libfc_priv *rp; + struct fc_rport_libfc_priv *rpriv; int rval; int rc = 0; struct fcoe_dev_stats *stats; - lp = shost_priv(sc_cmd->device->host); + lport = shost_priv(sc_cmd->device->host); rval = fc_remote_port_chkready(rport); if (rval) { @@ -1689,14 +1770,16 @@ int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *)) goto out; } - rp = rport->dd_data; + rpriv = rport->dd_data; - if (!fc_fcp_lport_queue_ready(lp)) { + 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(lp, GFP_ATOMIC); + fsp = fc_fcp_pkt_alloc(lport, GFP_ATOMIC); if (fsp == NULL) { rc = SCSI_MLQUEUE_HOST_BUSY; goto out; @@ -1706,8 +1789,9 @@ int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *)) * build the libfc request pkt */ fsp->cmd = sc_cmd; /* save the cmd */ - fsp->lp = lp; /* save the softc ptr */ + fsp->lp = lport; /* save the softc ptr */ fsp->rport = rport; /* set the remote port ptr */ + fsp->xfer_ddp = FC_XID_UNKNOWN; sc_cmd->scsi_done = done; /* @@ -1719,7 +1803,7 @@ int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *)) /* * setup the data direction */ - stats = fc_lport_get_stats(lp); + stats = fc_lport_get_stats(lport); if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) { fsp->req_flags = FC_SRB_READ; stats->InputRequests++; @@ -1733,7 +1817,7 @@ int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *)) stats->ControlRequests++; } - fsp->tgt_flags = rp->flags; + fsp->tgt_flags = rpriv->flags; init_timer(&fsp->timer); fsp->timer.data = (unsigned long)fsp; @@ -1743,7 +1827,7 @@ int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *)) * if we get -1 return then put the request in the pending * queue. */ - rval = fc_fcp_pkt_send(lp, fsp); + rval = fc_fcp_pkt_send(lport, fsp); if (rval != 0) { fsp->state = FC_SRB_FREE; fc_fcp_pkt_release(fsp); @@ -1755,18 +1839,17 @@ out: EXPORT_SYMBOL(fc_queuecommand); /** - * fc_io_compl() - Handle responses for completed commands - * @fsp: scsi packet - * - * Translates a error to a Linux SCSI error. + * 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 *lp; + struct fc_lport *lport; unsigned long flags; /* release outstanding ddp context */ @@ -1779,28 +1862,26 @@ static void fc_io_compl(struct fc_fcp_pkt *fsp) spin_lock_bh(&fsp->scsi_pkt_lock); } - lp = fsp->lp; - si = fc_get_scsi_internal(lp); - spin_lock_irqsave(lp->host->host_lock, flags); + lport = fsp->lp; + si = fc_get_scsi_internal(lport); + spin_lock_irqsave(lport->host->host_lock, flags); if (!fsp->cmd) { - spin_unlock_irqrestore(lp->host->host_lock, flags); + spin_unlock_irqrestore(lport->host->host_lock, flags); return; } /* - * if a command timed out while we had to try and throttle IO - * and it is now getting cleaned up, then we are about to - * try again so clear the throttled flag incase we get more - * time outs. + * if can_queue ramp down is done then try can_queue ramp up + * since commands are completing now. */ - if (si->throttled && fsp->state & FC_SRB_NOMEM) - si->throttled = 0; + if (si->last_can_queue_ramp_down_time) + fc_fcp_can_queue_ramp_up(lport); sc_cmd = fsp->cmd; fsp->cmd = NULL; if (!sc_cmd->SCp.ptr) { - spin_unlock_irqrestore(lp->host->host_lock, flags); + spin_unlock_irqrestore(lport->host->host_lock, flags); return; } @@ -1814,21 +1895,6 @@ static void fc_io_compl(struct fc_fcp_pkt *fsp) sc_cmd->result = DID_OK << 16; if (fsp->scsi_resid) CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid; - } else if (fsp->cdb_status == QUEUE_FULL) { - struct scsi_device *tmp_sdev; - struct scsi_device *sdev = sc_cmd->device; - - shost_for_each_device(tmp_sdev, sdev->host) { - if (tmp_sdev->id != sdev->id) - continue; - - if (tmp_sdev->queue_depth > 1) { - scsi_track_queue_full(tmp_sdev, - tmp_sdev-> - queue_depth - 1); - } - } - sc_cmd->result = (DID_OK << 16) | fsp->cdb_status; } else { /* * transport level I/O was ok but scsi @@ -1846,7 +1912,8 @@ static void fc_io_compl(struct fc_fcp_pkt *fsp) * scsi status is good but transport level * underrun. */ - sc_cmd->result = DID_OK << 16; + sc_cmd->result = (fsp->state & FC_SRB_RCV_STATUS ? + DID_OK : DID_ERROR) << 16; } else { /* * scsi got underrun, this is an error @@ -1881,60 +1948,42 @@ static void fc_io_compl(struct fc_fcp_pkt *fsp) list_del(&fsp->list); sc_cmd->SCp.ptr = NULL; sc_cmd->scsi_done(sc_cmd); - spin_unlock_irqrestore(lp->host->host_lock, flags); + spin_unlock_irqrestore(lport->host->host_lock, flags); /* release ref from initial allocation in queue command */ fc_fcp_pkt_release(fsp); } /** - * fc_fcp_complete() - complete processing of a fcp packet - * @fsp: fcp packet - * - * This function may sleep if a fsp timer is pending. - * The host lock must not be held by caller. - */ -void fc_fcp_complete(struct fc_fcp_pkt *fsp) -{ - if (fc_fcp_lock_pkt(fsp)) - return; - - fc_fcp_complete_locked(fsp); - fc_fcp_unlock_pkt(fsp); -} -EXPORT_SYMBOL(fc_fcp_complete); - -/** * fc_eh_abort() - Abort a command - * @sc_cmd: scsi command to abort + * @sc_cmd: The SCSI command to abort * - * From scsi host template. - * send ABTS to the target device and wait for the response - * sc_cmd is the pointer to the command to be aborted. + * 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 *lp; + struct fc_lport *lport; int rc = FAILED; unsigned long flags; - lp = shost_priv(sc_cmd->device->host); - if (lp->state != LPORT_ST_READY) + lport = shost_priv(sc_cmd->device->host); + if (lport->state != LPORT_ST_READY) return rc; - else if (!lp->link_up) + else if (!lport->link_up) return rc; - spin_lock_irqsave(lp->host->host_lock, flags); + spin_lock_irqsave(lport->host->host_lock, flags); fsp = CMD_SP(sc_cmd); if (!fsp) { /* command completed while scsi eh was setting up */ - spin_unlock_irqrestore(lp->host->host_lock, flags); + spin_unlock_irqrestore(lport->host->host_lock, flags); return SUCCESS; } /* grab a ref so the fsp and sc_cmd cannot be relased from under us */ fc_fcp_pkt_hold(fsp); - spin_unlock_irqrestore(lp->host->host_lock, flags); + spin_unlock_irqrestore(lport->host->host_lock, flags); if (fc_fcp_lock_pkt(fsp)) { /* completed while we were waiting for timer to be deleted */ @@ -1942,7 +1991,7 @@ int fc_eh_abort(struct scsi_cmnd *sc_cmd) goto release_pkt; } - rc = fc_fcp_pkt_abort(lp, fsp); + rc = fc_fcp_pkt_abort(fsp); fc_fcp_unlock_pkt(fsp); release_pkt: @@ -1952,37 +2001,34 @@ release_pkt: EXPORT_SYMBOL(fc_eh_abort); /** - * fc_eh_device_reset() Reset a single LUN - * @sc_cmd: scsi command + * 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 to send tm cmd to the target and wait for the - * response. + * Set from SCSI host template. */ int fc_eh_device_reset(struct scsi_cmnd *sc_cmd) { - struct fc_lport *lp; + struct fc_lport *lport; struct fc_fcp_pkt *fsp; struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device)); int rc = FAILED; - struct fc_rport_libfc_priv *rp; int rval; rval = fc_remote_port_chkready(rport); if (rval) goto out; - rp = rport->dd_data; - lp = shost_priv(sc_cmd->device->host); + lport = shost_priv(sc_cmd->device->host); - if (lp->state != LPORT_ST_READY) + if (lport->state != LPORT_ST_READY) return rc; - FC_SCSI_DBG(lp, "Resetting rport (%6x)\n", rport->port_id); + FC_SCSI_DBG(lport, "Resetting rport (%6x)\n", rport->port_id); - fsp = fc_fcp_pkt_alloc(lp, GFP_NOIO); + fsp = fc_fcp_pkt_alloc(lport, GFP_NOIO); if (fsp == NULL) { printk(KERN_WARNING "libfc: could not allocate scsi_pkt\n"); - sc_cmd->result = DID_NO_CONNECT << 16; goto out; } @@ -1991,13 +2037,13 @@ int fc_eh_device_reset(struct scsi_cmnd *sc_cmd) * the sc passed in is not setup for execution like when sent * through the queuecommand callout. */ - fsp->lp = lp; /* save the softc ptr */ + fsp->lp = lport; /* save the softc ptr */ fsp->rport = rport; /* set the remote port ptr */ /* * flush outstanding commands */ - rc = fc_lun_reset(lp, fsp, scmd_id(sc_cmd), sc_cmd->device->lun); + rc = fc_lun_reset(lport, fsp, scmd_id(sc_cmd), sc_cmd->device->lun); fsp->state = FC_SRB_FREE; fc_fcp_pkt_release(fsp); @@ -2007,38 +2053,39 @@ out: EXPORT_SYMBOL(fc_eh_device_reset); /** - * fc_eh_host_reset() - The reset function will reset the ports on the host. - * @sc_cmd: scsi command + * 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 *lp = shost_priv(shost); + struct fc_lport *lport = shost_priv(shost); unsigned long wait_tmo; - FC_SCSI_DBG(lp, "Resetting host\n"); + FC_SCSI_DBG(lport, "Resetting host\n"); - lp->tt.lport_reset(lp); + lport->tt.lport_reset(lport); wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT; - while (!fc_fcp_lport_queue_ready(lp) && time_before(jiffies, wait_tmo)) + while (!fc_fcp_lport_queue_ready(lport) && time_before(jiffies, + wait_tmo)) msleep(1000); - if (fc_fcp_lport_queue_ready(lp)) { + if (fc_fcp_lport_queue_ready(lport)) { shost_printk(KERN_INFO, shost, "libfc: Host reset succeeded " - "on port (%6x)\n", fc_host_port_id(lp->host)); + "on port (%6x)\n", fc_host_port_id(lport->host)); return SUCCESS; } else { shost_printk(KERN_INFO, shost, "libfc: Host reset failed, " "port (%6x) is not ready.\n", - fc_host_port_id(lp->host)); + fc_host_port_id(lport->host)); return FAILED; } } EXPORT_SYMBOL(fc_eh_host_reset); /** - * fc_slave_alloc() - configure queue depth - * @sdev: scsi device + * 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. @@ -2046,29 +2093,50 @@ EXPORT_SYMBOL(fc_eh_host_reset); int fc_slave_alloc(struct scsi_device *sdev) { struct fc_rport *rport = starget_to_rport(scsi_target(sdev)); - int queue_depth; if (!rport || fc_remote_port_chkready(rport)) return -ENXIO; - if (sdev->tagged_supported) { - if (sdev->host->hostt->cmd_per_lun) - queue_depth = sdev->host->hostt->cmd_per_lun; - else - queue_depth = FC_FCP_DFLT_QUEUE_DEPTH; - scsi_activate_tcq(sdev, queue_depth); - } + 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); -int fc_change_queue_depth(struct scsi_device *sdev, int qdepth) +/** + * 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) { - scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth); + 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) { @@ -2084,38 +2152,69 @@ int fc_change_queue_type(struct scsi_device *sdev, int tag_type) } EXPORT_SYMBOL(fc_change_queue_type); -void fc_fcp_destroy(struct fc_lport *lp) +/** + * 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(lp); + 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 (%6x)\n", fc_host_port_id(lp->host)); + "port (%6x)\n", fc_host_port_id(lport->host)); mempool_destroy(si->scsi_pkt_pool); kfree(si); - lp->scsi_priv = NULL; + lport->scsi_priv = NULL; } EXPORT_SYMBOL(fc_fcp_destroy); -int fc_fcp_init(struct fc_lport *lp) +int fc_setup_fcp() +{ + 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() +{ + 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 (!lp->tt.fcp_cmd_send) - lp->tt.fcp_cmd_send = fc_fcp_cmd_send; + if (!lport->tt.fcp_cmd_send) + lport->tt.fcp_cmd_send = fc_fcp_cmd_send; - if (!lp->tt.fcp_cleanup) - lp->tt.fcp_cleanup = fc_fcp_cleanup; + if (!lport->tt.fcp_cleanup) + lport->tt.fcp_cleanup = fc_fcp_cleanup; - if (!lp->tt.fcp_abort_io) - lp->tt.fcp_abort_io = fc_fcp_abort_io; + 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; - lp->scsi_priv = si; + lport->scsi_priv = si; + si->max_can_queue = lport->host->can_queue; INIT_LIST_HEAD(&si->scsi_pkt_queue); si->scsi_pkt_pool = mempool_create_slab_pool(2, scsi_pkt_cachep); @@ -2130,42 +2229,3 @@ free_internal: return rc; } EXPORT_SYMBOL(fc_fcp_init); - -static int __init libfc_init(void) -{ - int rc; - - scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt", - sizeof(struct fc_fcp_pkt), - 0, SLAB_HWCACHE_ALIGN, NULL); - if (scsi_pkt_cachep == NULL) { - printk(KERN_ERR "libfc: Unable to allocate SRB cache, " - "module load failed!"); - return -ENOMEM; - } - - rc = fc_setup_exch_mgr(); - if (rc) - goto destroy_pkt_cache; - - rc = fc_setup_rport(); - if (rc) - goto destroy_em; - - return rc; -destroy_em: - fc_destroy_exch_mgr(); -destroy_pkt_cache: - kmem_cache_destroy(scsi_pkt_cachep); - return rc; -} - -static void __exit libfc_exit(void) -{ - kmem_cache_destroy(scsi_pkt_cachep); - fc_destroy_exch_mgr(); - fc_destroy_rport(); -} - -module_init(libfc_init); -module_exit(libfc_exit); |