| /* |
| * 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 |
| */ |
| |
| /* |
| * Fibre Channel exchange and sequence handling. |
| */ |
| |
| #include <linux/timer.h> |
| #include <linux/slab.h> |
| #include <linux/err.h> |
| |
| #include <scsi/fc/fc_fc2.h> |
| |
| #include <scsi/libfc.h> |
| #include <scsi/fc_encode.h> |
| |
| #include "fc_libfc.h" |
| |
| u16 fc_cpu_mask; /* cpu mask for possible cpus */ |
| EXPORT_SYMBOL(fc_cpu_mask); |
| static u16 fc_cpu_order; /* 2's power to represent total possible cpus */ |
| static struct kmem_cache *fc_em_cachep; /* cache for exchanges */ |
| static struct workqueue_struct *fc_exch_workqueue; |
| |
| /* |
| * Structure and function definitions for managing Fibre Channel Exchanges |
| * and Sequences. |
| * |
| * The three primary structures used here are fc_exch_mgr, fc_exch, and fc_seq. |
| * |
| * fc_exch_mgr holds the exchange state for an N port |
| * |
| * fc_exch holds state for one exchange and links to its active sequence. |
| * |
| * fc_seq holds the state for an individual sequence. |
| */ |
| |
| /** |
| * struct fc_exch_pool - Per cpu exchange pool |
| * @next_index: Next possible free exchange index |
| * @total_exches: Total allocated exchanges |
| * @lock: Exch pool lock |
| * @ex_list: List of exchanges |
| * |
| * This structure manages per cpu exchanges in array of exchange pointers. |
| * This array is allocated followed by struct fc_exch_pool memory for |
| * assigned range of exchanges to per cpu pool. |
| */ |
| struct fc_exch_pool { |
| u16 next_index; |
| u16 total_exches; |
| |
| /* two cache of free slot in exch array */ |
| u16 left; |
| u16 right; |
| |
| spinlock_t lock; |
| struct list_head ex_list; |
| }; |
| |
| /** |
| * struct fc_exch_mgr - The Exchange Manager (EM). |
| * @class: Default class for new sequences |
| * @kref: Reference counter |
| * @min_xid: Minimum exchange ID |
| * @max_xid: Maximum exchange ID |
| * @ep_pool: Reserved exchange pointers |
| * @pool_max_index: Max exch array index in exch pool |
| * @pool: Per cpu exch pool |
| * @stats: Statistics structure |
| * |
| * This structure is the center for creating exchanges and sequences. |
| * It manages the allocation of exchange IDs. |
| */ |
| struct fc_exch_mgr { |
| enum fc_class class; |
| struct kref kref; |
| u16 min_xid; |
| u16 max_xid; |
| mempool_t *ep_pool; |
| u16 pool_max_index; |
| struct fc_exch_pool *pool; |
| |
| /* |
| * currently exchange mgr stats are updated but not used. |
| * either stats can be expose via sysfs or remove them |
| * all together if not used XXX |
| */ |
| struct { |
| atomic_t no_free_exch; |
| atomic_t no_free_exch_xid; |
| atomic_t xid_not_found; |
| atomic_t xid_busy; |
| atomic_t seq_not_found; |
| atomic_t non_bls_resp; |
| } stats; |
| }; |
| |
| /** |
| * struct fc_exch_mgr_anchor - primary structure for list of EMs |
| * @ema_list: Exchange Manager Anchor list |
| * @mp: Exchange Manager associated with this anchor |
| * @match: Routine to determine if this anchor's EM should be used |
| * |
| * When walking the list of anchors the match routine will be called |
| * for each anchor to determine if that EM should be used. The last |
| * anchor in the list will always match to handle any exchanges not |
| * handled by other EMs. The non-default EMs would be added to the |
| * anchor list by HW that provides FCoE offloads. |
| */ |
| struct fc_exch_mgr_anchor { |
| struct list_head ema_list; |
| struct fc_exch_mgr *mp; |
| bool (*match)(struct fc_frame *); |
| }; |
| |
| static void fc_exch_rrq(struct fc_exch *); |
| static void fc_seq_ls_acc(struct fc_frame *); |
| static void fc_seq_ls_rjt(struct fc_frame *, enum fc_els_rjt_reason, |
| enum fc_els_rjt_explan); |
| static void fc_exch_els_rec(struct fc_frame *); |
| static void fc_exch_els_rrq(struct fc_frame *); |
| |
| /* |
| * Internal implementation notes. |
| * |
| * The exchange manager is one by default in libfc but LLD may choose |
| * to have one per CPU. The sequence manager is one per exchange manager |
| * and currently never separated. |
| * |
| * Section 9.8 in FC-FS-2 specifies: "The SEQ_ID is a one-byte field |
| * assigned by the Sequence Initiator that shall be unique for a specific |
| * D_ID and S_ID pair while the Sequence is open." Note that it isn't |
| * qualified by exchange ID, which one might think it would be. |
| * In practice this limits the number of open sequences and exchanges to 256 |
| * per session. For most targets we could treat this limit as per exchange. |
| * |
| * The exchange and its sequence are freed when the last sequence is received. |
| * It's possible for the remote port to leave an exchange open without |
| * sending any sequences. |
| * |
| * Notes on reference counts: |
| * |
| * Exchanges are reference counted and exchange gets freed when the reference |
| * count becomes zero. |
| * |
| * Timeouts: |
| * Sequences are timed out for E_D_TOV and R_A_TOV. |
| * |
| * Sequence event handling: |
| * |
| * The following events may occur on initiator sequences: |
| * |
| * Send. |
| * For now, the whole thing is sent. |
| * Receive ACK |
| * This applies only to class F. |
| * The sequence is marked complete. |
| * ULP completion. |
| * The upper layer calls fc_exch_done() when done |
| * with exchange and sequence tuple. |
| * RX-inferred completion. |
| * When we receive the next sequence on the same exchange, we can |
| * retire the previous sequence ID. (XXX not implemented). |
| * Timeout. |
| * R_A_TOV frees the sequence ID. If we're waiting for ACK, |
| * E_D_TOV causes abort and calls upper layer response handler |
| * with FC_EX_TIMEOUT error. |
| * Receive RJT |
| * XXX defer. |
| * Send ABTS |
| * On timeout. |
| * |
| * The following events may occur on recipient sequences: |
| * |
| * Receive |
| * Allocate sequence for first frame received. |
| * Hold during receive handler. |
| * Release when final frame received. |
| * Keep status of last N of these for the ELS RES command. XXX TBD. |
| * Receive ABTS |
| * Deallocate sequence |
| * Send RJT |
| * Deallocate |
| * |
| * For now, we neglect conditions where only part of a sequence was |
| * received or transmitted, or where out-of-order receipt is detected. |
| */ |
| |
| /* |
| * Locking notes: |
| * |
| * The EM code run in a per-CPU worker thread. |
| * |
| * To protect against concurrency between a worker thread code and timers, |
| * sequence allocation and deallocation must be locked. |
| * - exchange refcnt can be done atomicly without locks. |
| * - sequence allocation must be locked by exch lock. |
| * - If the EM pool lock and ex_lock must be taken at the same time, then the |
| * EM pool lock must be taken before the ex_lock. |
| */ |
| |
| /* |
| * opcode names for debugging. |
| */ |
| static char *fc_exch_rctl_names[] = FC_RCTL_NAMES_INIT; |
| |
| /** |
| * fc_exch_name_lookup() - Lookup name by opcode |
| * @op: Opcode to be looked up |
| * @table: Opcode/name table |
| * @max_index: Index not to be exceeded |
| * |
| * This routine is used to determine a human-readable string identifying |
| * a R_CTL opcode. |
| */ |
| static inline const char *fc_exch_name_lookup(unsigned int op, char **table, |
| unsigned int max_index) |
| { |
| const char *name = NULL; |
| |
| if (op < max_index) |
| name = table[op]; |
| if (!name) |
| name = "unknown"; |
| return name; |
| } |
| |
| /** |
| * fc_exch_rctl_name() - Wrapper routine for fc_exch_name_lookup() |
| * @op: The opcode to be looked up |
| */ |
| static const char *fc_exch_rctl_name(unsigned int op) |
| { |
| return fc_exch_name_lookup(op, fc_exch_rctl_names, |
| ARRAY_SIZE(fc_exch_rctl_names)); |
| } |
| |
| /** |
| * fc_exch_hold() - Increment an exchange's reference count |
| * @ep: Echange to be held |
| */ |
| static inline void fc_exch_hold(struct fc_exch *ep) |
| { |
| atomic_inc(&ep->ex_refcnt); |
| } |
| |
| /** |
| * fc_exch_setup_hdr() - Initialize a FC header by initializing some fields |
| * and determine SOF and EOF. |
| * @ep: The exchange to that will use the header |
| * @fp: The frame whose header is to be modified |
| * @f_ctl: F_CTL bits that will be used for the frame header |
| * |
| * The fields initialized by this routine are: fh_ox_id, fh_rx_id, |
| * fh_seq_id, fh_seq_cnt and the SOF and EOF. |
| */ |
| static void fc_exch_setup_hdr(struct fc_exch *ep, struct fc_frame *fp, |
| u32 f_ctl) |
| { |
| struct fc_frame_header *fh = fc_frame_header_get(fp); |
| u16 fill; |
| |
| fr_sof(fp) = ep->class; |
| if (ep->seq.cnt) |
| fr_sof(fp) = fc_sof_normal(ep->class); |
| |
| if (f_ctl & FC_FC_END_SEQ) { |
| fr_eof(fp) = FC_EOF_T; |
| if (fc_sof_needs_ack(ep->class)) |
| fr_eof(fp) = FC_EOF_N; |
| /* |
| * From F_CTL. |
| * The number of fill bytes to make the length a 4-byte |
| * multiple is the low order 2-bits of the f_ctl. |
| * The fill itself will have been cleared by the frame |
| * allocation. |
| * After this, the length will be even, as expected by |
| * the transport. |
| */ |
| fill = fr_len(fp) & 3; |
| if (fill) { |
| fill = 4 - fill; |
| /* TODO, this may be a problem with fragmented skb */ |
| skb_put(fp_skb(fp), fill); |
| hton24(fh->fh_f_ctl, f_ctl | fill); |
| } |
| } else { |
| WARN_ON(fr_len(fp) % 4 != 0); /* no pad to non last frame */ |
| fr_eof(fp) = FC_EOF_N; |
| } |
| |
| /* |
| * Initialize remainig fh fields |
| * from fc_fill_fc_hdr |
| */ |
| fh->fh_ox_id = htons(ep->oxid); |
| fh->fh_rx_id = htons(ep->rxid); |
| fh->fh_seq_id = ep->seq.id; |
| fh->fh_seq_cnt = htons(ep->seq.cnt); |
| } |
| |
| /** |
| * fc_exch_release() - Decrement an exchange's reference count |
| * @ep: Exchange to be released |
| * |
| * If the reference count reaches zero and the exchange is complete, |
| * it is freed. |
| */ |
| static void fc_exch_release(struct fc_exch *ep) |
| { |
| struct fc_exch_mgr *mp; |
| |
| if (atomic_dec_and_test(&ep->ex_refcnt)) { |
| mp = ep->em; |
| if (ep->destructor) |
| ep->destructor(&ep->seq, ep->arg); |
| WARN_ON(!(ep->esb_stat & ESB_ST_COMPLETE)); |
| mempool_free(ep, mp->ep_pool); |
| } |
| } |
| |
| /** |
| * fc_exch_done_locked() - Complete an exchange with the exchange lock held |
| * @ep: The exchange that is complete |
| */ |
| static int fc_exch_done_locked(struct fc_exch *ep) |
| { |
| int rc = 1; |
| |
| /* |
| * We must check for completion in case there are two threads |
| * tyring to complete this. But the rrq code will reuse the |
| * ep, and in that case we only clear the resp and set it as |
| * complete, so it can be reused by the timer to send the rrq. |
| */ |
| ep->resp = NULL; |
| if (ep->state & FC_EX_DONE) |
| return rc; |
| ep->esb_stat |= ESB_ST_COMPLETE; |
| |
| if (!(ep->esb_stat & ESB_ST_REC_QUAL)) { |
| ep->state |= FC_EX_DONE; |
| if (cancel_delayed_work(&ep->timeout_work)) |
| atomic_dec(&ep->ex_refcnt); /* drop hold for timer */ |
| rc = 0; |
| } |
| return rc; |
| } |
| |
| /** |
| * fc_exch_ptr_get() - Return an exchange from an exchange pool |
| * @pool: Exchange Pool to get an exchange from |
| * @index: Index of the exchange within the pool |
| * |
| * Use the index to get an exchange from within an exchange pool. exches |
| * will point to an array of exchange pointers. The index will select |
| * the exchange within the array. |
| */ |
| static inline struct fc_exch *fc_exch_ptr_get(struct fc_exch_pool *pool, |
| u16 index) |
| { |
| struct fc_exch **exches = (struct fc_exch **)(pool + 1); |
| return exches[index]; |
| } |
| |
| /** |
| * fc_exch_ptr_set() - Assign an exchange to a slot in an exchange pool |
| * @pool: The pool to assign the exchange to |
| * @index: The index in the pool where the exchange will be assigned |
| * @ep: The exchange to assign to the pool |
| */ |
| static inline void fc_exch_ptr_set(struct fc_exch_pool *pool, u16 index, |
| struct fc_exch *ep) |
| { |
| ((struct fc_exch **)(pool + 1))[index] = ep; |
| } |
| |
| /** |
| * fc_exch_delete() - Delete an exchange |
| * @ep: The exchange to be deleted |
| */ |
| static void fc_exch_delete(struct fc_exch *ep) |
| { |
| struct fc_exch_pool *pool; |
| u16 index; |
| |
| pool = ep->pool; |
| spin_lock_bh(&pool->lock); |
| WARN_ON(pool->total_exches <= 0); |
| pool->total_exches--; |
| |
| /* update cache of free slot */ |
| index = (ep->xid - ep->em->min_xid) >> fc_cpu_order; |
| if (pool->left == FC_XID_UNKNOWN) |
| pool->left = index; |
| else if (pool->right == FC_XID_UNKNOWN) |
| pool->right = index; |
| else |
| pool->next_index = index; |
| |
| fc_exch_ptr_set(pool, index, NULL); |
| list_del(&ep->ex_list); |
| spin_unlock_bh(&pool->lock); |
| fc_exch_release(ep); /* drop hold for exch in mp */ |
| } |
| |
| /** |
| * fc_exch_timer_set_locked() - Start a timer for an exchange w/ the |
| * the exchange lock held |
| * @ep: The exchange whose timer will start |
| * @timer_msec: The timeout period |
| * |
| * Used for upper level protocols to time out the exchange. |
| * The timer is cancelled when it fires or when the exchange completes. |
| */ |
| static inline void fc_exch_timer_set_locked(struct fc_exch *ep, |
| unsigned int timer_msec) |
| { |
| if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) |
| return; |
| |
| FC_EXCH_DBG(ep, "Exchange timer armed\n"); |
| |
| if (queue_delayed_work(fc_exch_workqueue, &ep->timeout_work, |
| msecs_to_jiffies(timer_msec))) |
| fc_exch_hold(ep); /* hold for timer */ |
| } |
| |
| /** |
| * fc_exch_timer_set() - Lock the exchange and set the timer |
| * @ep: The exchange whose timer will start |
| * @timer_msec: The timeout period |
| */ |
| static void fc_exch_timer_set(struct fc_exch *ep, unsigned int timer_msec) |
| { |
| spin_lock_bh(&ep->ex_lock); |
| fc_exch_timer_set_locked(ep, timer_msec); |
| spin_unlock_bh(&ep->ex_lock); |
| } |
| |
| /** |
| * fc_seq_send() - Send a frame using existing sequence/exchange pair |
| * @lport: The local port that the exchange will be sent on |
| * @sp: The sequence to be sent |
| * @fp: The frame to be sent on the exchange |
| */ |
| static int fc_seq_send(struct fc_lport *lport, struct fc_seq *sp, |
| struct fc_frame *fp) |
| { |
| struct fc_exch *ep; |
| struct fc_frame_header *fh = fc_frame_header_get(fp); |
| int error; |
| u32 f_ctl; |
| |
| ep = fc_seq_exch(sp); |
| WARN_ON((ep->esb_stat & ESB_ST_SEQ_INIT) != ESB_ST_SEQ_INIT); |
| |
| f_ctl = ntoh24(fh->fh_f_ctl); |
| fc_exch_setup_hdr(ep, fp, f_ctl); |
| fr_encaps(fp) = ep->encaps; |
| |
| /* |
| * update sequence count if this frame is carrying |
| * multiple FC frames when sequence offload is enabled |
| * by LLD. |
| */ |
| if (fr_max_payload(fp)) |
| sp->cnt += DIV_ROUND_UP((fr_len(fp) - sizeof(*fh)), |
| fr_max_payload(fp)); |
| else |
| sp->cnt++; |
| |
| /* |
| * Send the frame. |
| */ |
| error = lport->tt.frame_send(lport, fp); |
| |
| /* |
| * Update the exchange and sequence flags, |
| * assuming all frames for the sequence have been sent. |
| * We can only be called to send once for each sequence. |
| */ |
| spin_lock_bh(&ep->ex_lock); |
| ep->f_ctl = f_ctl & ~FC_FC_FIRST_SEQ; /* not first seq */ |
| if (f_ctl & FC_FC_SEQ_INIT) |
| ep->esb_stat &= ~ESB_ST_SEQ_INIT; |
| spin_unlock_bh(&ep->ex_lock); |
| return error; |
| } |
| |
| /** |
| * fc_seq_alloc() - Allocate a sequence for a given exchange |
| * @ep: The exchange to allocate a new sequence for |
| * @seq_id: The sequence ID to be used |
| * |
| * We don't support multiple originated sequences on the same exchange. |
| * By implication, any previously originated sequence on this exchange |
| * is complete, and we reallocate the same sequence. |
| */ |
| static struct fc_seq *fc_seq_alloc(struct fc_exch *ep, u8 seq_id) |
| { |
| struct fc_seq *sp; |
| |
| sp = &ep->seq; |
| sp->ssb_stat = 0; |
| sp->cnt = 0; |
| sp->id = seq_id; |
| return sp; |
| } |
| |
| /** |
| * fc_seq_start_next_locked() - Allocate a new sequence on the same |
| * exchange as the supplied sequence |
| * @sp: The sequence/exchange to get a new sequence for |
| */ |
| static struct fc_seq *fc_seq_start_next_locked(struct fc_seq *sp) |
| { |
| struct fc_exch *ep = fc_seq_exch(sp); |
| |
| sp = fc_seq_alloc(ep, ep->seq_id++); |
| FC_EXCH_DBG(ep, "f_ctl %6x seq %2x\n", |
| ep->f_ctl, sp->id); |
| return sp; |
| } |
| |
| /** |
| * fc_seq_start_next() - Lock the exchange and get a new sequence |
| * for a given sequence/exchange pair |
| * @sp: The sequence/exchange to get a new exchange for |
| */ |
| static struct fc_seq *fc_seq_start_next(struct fc_seq *sp) |
| { |
| struct fc_exch *ep = fc_seq_exch(sp); |
| |
| spin_lock_bh(&ep->ex_lock); |
| sp = fc_seq_start_next_locked(sp); |
| spin_unlock_bh(&ep->ex_lock); |
| |
| return sp; |
| } |
| |
| /* |
| * Set the response handler for the exchange associated with a sequence. |
| */ |
| static void fc_seq_set_resp(struct fc_seq *sp, |
| void (*resp)(struct fc_seq *, struct fc_frame *, |
| void *), |
| void *arg) |
| { |
| struct fc_exch *ep = fc_seq_exch(sp); |
| |
| spin_lock_bh(&ep->ex_lock); |
| ep->resp = resp; |
| ep->arg = arg; |
| spin_unlock_bh(&ep->ex_lock); |
| } |
| |
| /** |
| * fc_seq_exch_abort() - Abort an exchange and sequence |
| * @req_sp: The sequence to be aborted |
| * @timer_msec: The period of time to wait before aborting |
| * |
| * Generally called because of a timeout or an abort from the upper layer. |
| */ |
| static int fc_seq_exch_abort(const struct fc_seq *req_sp, |
| unsigned int timer_msec) |
| { |
| struct fc_seq *sp; |
| struct fc_exch *ep; |
| struct fc_frame *fp; |
| int error; |
| |
| ep = fc_seq_exch(req_sp); |
| |
| spin_lock_bh(&ep->ex_lock); |
| if (ep->esb_stat & (ESB_ST_COMPLETE | ESB_ST_ABNORMAL) || |
| ep->state & (FC_EX_DONE | FC_EX_RST_CLEANUP)) { |
| spin_unlock_bh(&ep->ex_lock); |
| return -ENXIO; |
| } |
| |
| /* |
| * Send the abort on a new sequence if possible. |
| */ |
| sp = fc_seq_start_next_locked(&ep->seq); |
| if (!sp) { |
| spin_unlock_bh(&ep->ex_lock); |
| return -ENOMEM; |
| } |
| |
| ep->esb_stat |= ESB_ST_SEQ_INIT | ESB_ST_ABNORMAL; |
| if (timer_msec) |
| fc_exch_timer_set_locked(ep, timer_msec); |
| spin_unlock_bh(&ep->ex_lock); |
| |
| /* |
| * If not logged into the fabric, don't send ABTS but leave |
| * sequence active until next timeout. |
| */ |
| if (!ep->sid) |
| return 0; |
| |
| /* |
| * Send an abort for the sequence that timed out. |
| */ |
| fp = fc_frame_alloc(ep->lp, 0); |
| if (fp) { |
| fc_fill_fc_hdr(fp, FC_RCTL_BA_ABTS, ep->did, ep->sid, |
| FC_TYPE_BLS, FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0); |
| error = fc_seq_send(ep->lp, sp, fp); |
| } else |
| error = -ENOBUFS; |
| return error; |
| } |
| |
| /** |
| * fc_exch_timeout() - Handle exchange timer expiration |
| * @work: The work_struct identifying the exchange that timed out |
| */ |
| static void fc_exch_timeout(struct work_struct *work) |
| { |
| struct fc_exch *ep = container_of(work, struct fc_exch, |
| timeout_work.work); |
| struct fc_seq *sp = &ep->seq; |
| void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg); |
| void *arg; |
| u32 e_stat; |
| int rc = 1; |
| |
| FC_EXCH_DBG(ep, "Exchange timed out\n"); |
| |
| spin_lock_bh(&ep->ex_lock); |
| if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) |
| goto unlock; |
| |
| e_stat = ep->esb_stat; |
| if (e_stat & ESB_ST_COMPLETE) { |
| ep->esb_stat = e_stat & ~ESB_ST_REC_QUAL; |
| spin_unlock_bh(&ep->ex_lock); |
| if (e_stat & ESB_ST_REC_QUAL) |
| fc_exch_rrq(ep); |
| goto done; |
| } else { |
| resp = ep->resp; |
| arg = ep->arg; |
| ep->resp = NULL; |
| if (e_stat & ESB_ST_ABNORMAL) |
| rc = fc_exch_done_locked(ep); |
| spin_unlock_bh(&ep->ex_lock); |
| if (!rc) |
| fc_exch_delete(ep); |
| if (resp) |
| resp(sp, ERR_PTR(-FC_EX_TIMEOUT), arg); |
| fc_seq_exch_abort(sp, 2 * ep->r_a_tov); |
| goto done; |
| } |
| unlock: |
| spin_unlock_bh(&ep->ex_lock); |
| done: |
| /* |
| * This release matches the hold taken when the timer was set. |
| */ |
| fc_exch_release(ep); |
| } |
| |
| /** |
| * fc_exch_em_alloc() - Allocate an exchange from a specified EM. |
| * @lport: The local port that the exchange is for |
| * @mp: The exchange manager that will allocate the exchange |
| * |
| * Returns pointer to allocated fc_exch with exch lock held. |
| */ |
| static struct fc_exch *fc_exch_em_alloc(struct fc_lport *lport, |
| struct fc_exch_mgr *mp) |
| { |
| struct fc_exch *ep; |
| unsigned int cpu; |
| u16 index; |
| struct fc_exch_pool *pool; |
| |
| /* allocate memory for exchange */ |
| ep = mempool_alloc(mp->ep_pool, GFP_ATOMIC); |
| if (!ep) { |
| atomic_inc(&mp->stats.no_free_exch); |
| goto out; |
| } |
| memset(ep, 0, sizeof(*ep)); |
| |
| cpu = get_cpu(); |
| pool = per_cpu_ptr(mp->pool, cpu); |
| spin_lock_bh(&pool->lock); |
| put_cpu(); |
| |
| /* peek cache of free slot */ |
| if (pool->left != FC_XID_UNKNOWN) { |
| index = pool->left; |
| pool->left = FC_XID_UNKNOWN; |
| goto hit; |
| } |
| if (pool->right != FC_XID_UNKNOWN) { |
| index = pool->right; |
| pool->right = FC_XID_UNKNOWN; |
| goto hit; |
| } |
| |
| index = pool->next_index; |
| /* allocate new exch from pool */ |
| while (fc_exch_ptr_get(pool, index)) { |
| index = index == mp->pool_max_index ? 0 : index + 1; |
| if (index == pool->next_index) |
| goto err; |
| } |
| pool->next_index = index == mp->pool_max_index ? 0 : index + 1; |
| hit: |
| fc_exch_hold(ep); /* hold for exch in mp */ |
| spin_lock_init(&ep->ex_lock); |
| /* |
| * Hold exch lock for caller to prevent fc_exch_reset() |
| * from releasing exch while fc_exch_alloc() caller is |
| * still working on exch. |
| */ |
| spin_lock_bh(&ep->ex_lock); |
| |
| fc_exch_ptr_set(pool, index, ep); |
| list_add_tail(&ep->ex_list, &pool->ex_list); |
| fc_seq_alloc(ep, ep->seq_id++); |
| pool->total_exches++; |
| spin_unlock_bh(&pool->lock); |
| |
| /* |
| * update exchange |
| */ |
| ep->oxid = ep->xid = (index << fc_cpu_order | cpu) + mp->min_xid; |
| ep->em = mp; |
| ep->pool = pool; |
| ep->lp = lport; |
| ep->f_ctl = FC_FC_FIRST_SEQ; /* next seq is first seq */ |
| ep->rxid = FC_XID_UNKNOWN; |
| ep->class = mp->class; |
| INIT_DELAYED_WORK(&ep->timeout_work, fc_exch_timeout); |
| out: |
| return ep; |
| err: |
| spin_unlock_bh(&pool->lock); |
| atomic_inc(&mp->stats.no_free_exch_xid); |
| mempool_free(ep, mp->ep_pool); |
| return NULL; |
| } |
| |
| /** |
| * fc_exch_alloc() - Allocate an exchange from an EM on a |
| * local port's list of EMs. |
| * @lport: The local port that will own the exchange |
| * @fp: The FC frame that the exchange will be for |
| * |
| * This function walks the list of exchange manager(EM) |
| * anchors to select an EM for a new exchange allocation. The |
| * EM is selected when a NULL match function pointer is encountered |
| * or when a call to a match function returns true. |
| */ |
| static inline struct fc_exch *fc_exch_alloc(struct fc_lport *lport, |
| struct fc_frame *fp) |
| { |
| struct fc_exch_mgr_anchor *ema; |
| |
| list_for_each_entry(ema, &lport->ema_list, ema_list) |
| if (!ema->match || ema->match(fp)) |
| return fc_exch_em_alloc(lport, ema->mp); |
| return NULL; |
| } |
| |
| /** |
| * fc_exch_find() - Lookup and hold an exchange |
| * @mp: The exchange manager to lookup the exchange from |
| * @xid: The XID of the exchange to look up |
| */ |
| static struct fc_exch *fc_exch_find(struct fc_exch_mgr *mp, u16 xid) |
| { |
| struct fc_exch_pool *pool; |
| struct fc_exch *ep = NULL; |
| |
| if ((xid >= mp->min_xid) && (xid <= mp->max_xid)) { |
| pool = per_cpu_ptr(mp->pool, xid & fc_cpu_mask); |
| spin_lock_bh(&pool->lock); |
| ep = fc_exch_ptr_get(pool, (xid - mp->min_xid) >> fc_cpu_order); |
| if (ep) { |
| fc_exch_hold(ep); |
| WARN_ON(ep->xid != xid); |
| } |
| spin_unlock_bh(&pool->lock); |
| } |
| return ep; |
| } |
| |
| |
| /** |
| * fc_exch_done() - Indicate that an exchange/sequence tuple is complete and |
| * the memory allocated for the related objects may be freed. |
| * @sp: The sequence that has completed |
| */ |
| static void fc_exch_done(struct fc_seq *sp) |
| { |
| struct fc_exch *ep = fc_seq_exch(sp); |
| int rc; |
| |
| spin_lock_bh(&ep->ex_lock); |
| rc = fc_exch_done_locked(ep); |
| spin_unlock_bh(&ep->ex_lock); |
| if (!rc) |
| fc_exch_delete(ep); |
| } |
| |
| /** |
| * fc_exch_resp() - Allocate a new exchange for a response frame |
| * @lport: The local port that the exchange was for |
| * @mp: The exchange manager to allocate the exchange from |
| * @fp: The response frame |
| * |
| * Sets the responder ID in the frame header. |
| */ |
| static struct fc_exch *fc_exch_resp(struct fc_lport *lport, |
| struct fc_exch_mgr *mp, |
| struct fc_frame *fp) |
| { |
| struct fc_exch *ep; |
| struct fc_frame_header *fh; |
| |
| ep = fc_exch_alloc(lport, fp); |
| if (ep) { |
| ep->class = fc_frame_class(fp); |
| |
| /* |
| * Set EX_CTX indicating we're responding on this exchange. |
| */ |
| ep->f_ctl |= FC_FC_EX_CTX; /* we're responding */ |
| ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not new */ |
| fh = fc_frame_header_get(fp); |
| ep->sid = ntoh24(fh->fh_d_id); |
| ep->did = ntoh24(fh->fh_s_id); |
| ep->oid = ep->did; |
| |
| /* |
| * Allocated exchange has placed the XID in the |
| * originator field. Move it to the responder field, |
| * and set the originator XID from the frame. |
| */ |
| ep->rxid = ep->xid; |
| ep->oxid = ntohs(fh->fh_ox_id); |
| ep->esb_stat |= ESB_ST_RESP | ESB_ST_SEQ_INIT; |
| if ((ntoh24(fh->fh_f_ctl) & FC_FC_SEQ_INIT) == 0) |
| ep->esb_stat &= ~ESB_ST_SEQ_INIT; |
| |
| fc_exch_hold(ep); /* hold for caller */ |
| spin_unlock_bh(&ep->ex_lock); /* lock from fc_exch_alloc */ |
| } |
| return ep; |
| } |
| |
| /** |
| * fc_seq_lookup_recip() - Find a sequence where the other end |
| * originated the sequence |
| * @lport: The local port that the frame was sent to |
| * @mp: The Exchange Manager to lookup the exchange from |
| * @fp: The frame associated with the sequence we're looking for |
| * |
| * If fc_pf_rjt_reason is FC_RJT_NONE then this function will have a hold |
| * on the ep that should be released by the caller. |
| */ |
| static enum fc_pf_rjt_reason fc_seq_lookup_recip(struct fc_lport *lport, |
| struct fc_exch_mgr *mp, |
| struct fc_frame *fp) |
| { |
| struct fc_frame_header *fh = fc_frame_header_get(fp); |
| struct fc_exch *ep = NULL; |
| struct fc_seq *sp = NULL; |
| enum fc_pf_rjt_reason reject = FC_RJT_NONE; |
| u32 f_ctl; |
| u16 xid; |
| |
| f_ctl = ntoh24(fh->fh_f_ctl); |
| WARN_ON((f_ctl & FC_FC_SEQ_CTX) != 0); |
| |
| /* |
| * Lookup or create the exchange if we will be creating the sequence. |
| */ |
| if (f_ctl & FC_FC_EX_CTX) { |
| xid = ntohs(fh->fh_ox_id); /* we originated exch */ |
| ep = fc_exch_find(mp, xid); |
| if (!ep) { |
| atomic_inc(&mp->stats.xid_not_found); |
| reject = FC_RJT_OX_ID; |
| goto out; |
| } |
| if (ep->rxid == FC_XID_UNKNOWN) |
| ep->rxid = ntohs(fh->fh_rx_id); |
| else if (ep->rxid != ntohs(fh->fh_rx_id)) { |
| reject = FC_RJT_OX_ID; |
| goto rel; |
| } |
| } else { |
| xid = ntohs(fh->fh_rx_id); /* we are the responder */ |
| |
| /* |
| * Special case for MDS issuing an ELS TEST with a |
| * bad rxid of 0. |
| * XXX take this out once we do the proper reject. |
| */ |
| if (xid == 0 && fh->fh_r_ctl == FC_RCTL_ELS_REQ && |
| fc_frame_payload_op(fp) == ELS_TEST) { |
| fh->fh_rx_id = htons(FC_XID_UNKNOWN); |
| xid = FC_XID_UNKNOWN; |
| } |
| |
| /* |
| * new sequence - find the exchange |
| */ |
| ep = fc_exch_find(mp, xid); |
| if ((f_ctl & FC_FC_FIRST_SEQ) && fc_sof_is_init(fr_sof(fp))) { |
| if (ep) { |
| atomic_inc(&mp->stats.xid_busy); |
| reject = FC_RJT_RX_ID; |
| goto rel; |
| } |
| ep = fc_exch_resp(lport, mp, fp); |
| if (!ep) { |
| reject = FC_RJT_EXCH_EST; /* XXX */ |
| goto out; |
| } |
| xid = ep->xid; /* get our XID */ |
| } else if (!ep) { |
| atomic_inc(&mp->stats.xid_not_found); |
| reject = FC_RJT_RX_ID; /* XID not found */ |
| goto out; |
| } |
| } |
| |
| /* |
| * At this point, we have the exchange held. |
| * Find or create the sequence. |
| */ |
| if (fc_sof_is_init(fr_sof(fp))) { |
| sp = &ep->seq; |
| sp->ssb_stat |= SSB_ST_RESP; |
| sp->id = fh->fh_seq_id; |
| } else { |
| sp = &ep->seq; |
| if (sp->id != fh->fh_seq_id) { |
| atomic_inc(&mp->stats.seq_not_found); |
| if (f_ctl & FC_FC_END_SEQ) { |
| /* |
| * Update sequence_id based on incoming last |
| * frame of sequence exchange. This is needed |
| * for FCoE target where DDP has been used |
| * on target where, stack is indicated only |
| * about last frame's (payload _header) header. |
| * Whereas "seq_id" which is part of |
| * frame_header is allocated by initiator |
| * which is totally different from "seq_id" |
| * allocated when XFER_RDY was sent by target. |
| * To avoid false -ve which results into not |
| * sending RSP, hence write request on other |
| * end never finishes. |
| */ |
| spin_lock_bh(&ep->ex_lock); |
| sp->ssb_stat |= SSB_ST_RESP; |
| sp->id = fh->fh_seq_id; |
| spin_unlock_bh(&ep->ex_lock); |
| } else { |
| /* sequence/exch should exist */ |
| reject = FC_RJT_SEQ_ID; |
| goto rel; |
| } |
| } |
| } |
| WARN_ON(ep != fc_seq_exch(sp)); |
| |
| if (f_ctl & FC_FC_SEQ_INIT) |
| ep->esb_stat |= ESB_ST_SEQ_INIT; |
| |
| fr_seq(fp) = sp; |
| out: |
| return reject; |
| rel: |
| fc_exch_done(&ep->seq); |
| fc_exch_release(ep); /* hold from fc_exch_find/fc_exch_resp */ |
| return reject; |
| } |
| |
| /** |
| * fc_seq_lookup_orig() - Find a sequence where this end |
| * originated the sequence |
| * @mp: The Exchange Manager to lookup the exchange from |
| * @fp: The frame associated with the sequence we're looking for |
| * |
| * Does not hold the sequence for the caller. |
| */ |
| static struct fc_seq *fc_seq_lookup_orig(struct fc_exch_mgr *mp, |
| struct fc_frame *fp) |
| { |
| struct fc_frame_header *fh = fc_frame_header_get(fp); |
| struct fc_exch *ep; |
| struct fc_seq *sp = NULL; |
| u32 f_ctl; |
| u16 xid; |
| |
| f_ctl = ntoh24(fh->fh_f_ctl); |
| WARN_ON((f_ctl & FC_FC_SEQ_CTX) != FC_FC_SEQ_CTX); |
| xid = ntohs((f_ctl & FC_FC_EX_CTX) ? fh->fh_ox_id : fh->fh_rx_id); |
| ep = fc_exch_find(mp, xid); |
| if (!ep) |
| return NULL; |
| if (ep->seq.id == fh->fh_seq_id) { |
| /* |
| * Save the RX_ID if we didn't previously know it. |
| */ |
| sp = &ep->seq; |
| if ((f_ctl & FC_FC_EX_CTX) != 0 && |
| ep->rxid == FC_XID_UNKNOWN) { |
| ep->rxid = ntohs(fh->fh_rx_id); |
| } |
| } |
| fc_exch_release(ep); |
| return sp; |
| } |
| |
| /** |
| * fc_exch_set_addr() - Set the source and destination IDs for an exchange |
| * @ep: The exchange to set the addresses for |
| * @orig_id: The originator's ID |
| * @resp_id: The responder's ID |
| * |
| * Note this must be done before the first sequence of the exchange is sent. |
| */ |
| static void fc_exch_set_addr(struct fc_exch *ep, |
| u32 orig_id, u32 resp_id) |
| { |
| ep->oid = orig_id; |
| if (ep->esb_stat & ESB_ST_RESP) { |
| ep->sid = resp_id; |
| ep->did = orig_id; |
| } else { |
| ep->sid = orig_id; |
| ep->did = resp_id; |
| } |
| } |
| |
| /** |
| * fc_seq_els_rsp_send() - Send an ELS response using information from |
| * the existing sequence/exchange. |
| * @fp: The received frame |
| * @els_cmd: The ELS command to be sent |
| * @els_data: The ELS data to be sent |
| * |
| * The received frame is not freed. |
| */ |
| static void fc_seq_els_rsp_send(struct fc_frame *fp, enum fc_els_cmd els_cmd, |
| struct fc_seq_els_data *els_data) |
| { |
| switch (els_cmd) { |
| case ELS_LS_RJT: |
| fc_seq_ls_rjt(fp, els_data->reason, els_data->explan); |
| break; |
| case ELS_LS_ACC: |
| fc_seq_ls_acc(fp); |
| break; |
| case ELS_RRQ: |
| fc_exch_els_rrq(fp); |
| break; |
| case ELS_REC: |
| fc_exch_els_rec(fp); |
| break; |
| default: |
| FC_LPORT_DBG(fr_dev(fp), "Invalid ELS CMD:%x\n", els_cmd); |
| } |
| } |
| |
| /** |
| * fc_seq_send_last() - Send a sequence that is the last in the exchange |
| * @sp: The sequence that is to be sent |
| * @fp: The frame that will be sent on the sequence |
| * @rctl: The R_CTL information to be sent |
| * @fh_type: The frame header type |
| */ |
| static void fc_seq_send_last(struct fc_seq *sp, struct fc_frame *fp, |
| enum fc_rctl rctl, enum fc_fh_type fh_type) |
| { |
| u32 f_ctl; |
| struct fc_exch *ep = fc_seq_exch(sp); |
| |
| f_ctl = FC_FC_LAST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT; |
| f_ctl |= ep->f_ctl; |
| fc_fill_fc_hdr(fp, rctl, ep->did, ep->sid, fh_type, f_ctl, 0); |
| fc_seq_send(ep->lp, sp, fp); |
| } |
| |
| /** |
| * fc_seq_send_ack() - Send an acknowledgement that we've received a frame |
| * @sp: The sequence to send the ACK on |
| * @rx_fp: The received frame that is being acknoledged |
| * |
| * Send ACK_1 (or equiv.) indicating we received something. |
| */ |
| static void fc_seq_send_ack(struct fc_seq *sp, const struct fc_frame *rx_fp) |
| { |
| struct fc_frame *fp; |
| struct fc_frame_header *rx_fh; |
| struct fc_frame_header *fh; |
| struct fc_exch *ep = fc_seq_exch(sp); |
| struct fc_lport *lport = ep->lp; |
| unsigned int f_ctl; |
| |
| /* |
| * Don't send ACKs for class 3. |
| */ |
| if (fc_sof_needs_ack(fr_sof(rx_fp))) { |
| fp = fc_frame_alloc(lport, 0); |
| if (!fp) |
| return; |
| |
| fh = fc_frame_header_get(fp); |
| fh->fh_r_ctl = FC_RCTL_ACK_1; |
| fh->fh_type = FC_TYPE_BLS; |
| |
| /* |
| * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22). |
| * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT. |
| * Bits 9-8 are meaningful (retransmitted or unidirectional). |
| * Last ACK uses bits 7-6 (continue sequence), |
| * bits 5-4 are meaningful (what kind of ACK to use). |
| */ |
| rx_fh = fc_frame_header_get(rx_fp); |
| f_ctl = ntoh24(rx_fh->fh_f_ctl); |
| f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX | |
| FC_FC_FIRST_SEQ | FC_FC_LAST_SEQ | |
| FC_FC_END_SEQ | FC_FC_END_CONN | FC_FC_SEQ_INIT | |
| FC_FC_RETX_SEQ | FC_FC_UNI_TX; |
| f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX; |
| hton24(fh->fh_f_ctl, f_ctl); |
| |
| fc_exch_setup_hdr(ep, fp, f_ctl); |
| fh->fh_seq_id = rx_fh->fh_seq_id; |
| fh->fh_seq_cnt = rx_fh->fh_seq_cnt; |
| fh->fh_parm_offset = htonl(1); /* ack single frame */ |
| |
| fr_sof(fp) = fr_sof(rx_fp); |
| if (f_ctl & FC_FC_END_SEQ) |
| fr_eof(fp) = FC_EOF_T; |
| else |
| fr_eof(fp) = FC_EOF_N; |
| |
| lport->tt.frame_send(lport, fp); |
| } |
| } |
| |
| /** |
| * fc_exch_send_ba_rjt() - Send BLS Reject |
| * @rx_fp: The frame being rejected |
| * @reason: The reason the frame is being rejected |
| * @explan: The explanation for the rejection |
| * |
| * This is for rejecting BA_ABTS only. |
| */ |
| static void fc_exch_send_ba_rjt(struct fc_frame *rx_fp, |
| enum fc_ba_rjt_reason reason, |
| enum fc_ba_rjt_explan explan) |
| { |
| struct fc_frame *fp; |
| struct fc_frame_header *rx_fh; |
| struct fc_frame_header *fh; |
| struct fc_ba_rjt *rp; |
| struct fc_lport *lport; |
| unsigned int f_ctl; |
| |
| lport = fr_dev(rx_fp); |
| fp = fc_frame_alloc(lport, sizeof(*rp)); |
| if (!fp) |
| return; |
| fh = fc_frame_header_get(fp); |
| rx_fh = fc_frame_header_get(rx_fp); |
| |
| memset(fh, 0, sizeof(*fh) + sizeof(*rp)); |
| |
| rp = fc_frame_payload_get(fp, sizeof(*rp)); |
| rp->br_reason = reason; |
| rp->br_explan = explan; |
| |
| /* |
| * seq_id, cs_ctl, df_ctl and param/offset are zero. |
| */ |
| memcpy(fh->fh_s_id, rx_fh->fh_d_id, 3); |
| memcpy(fh->fh_d_id, rx_fh->fh_s_id, 3); |
| fh->fh_ox_id = rx_fh->fh_ox_id; |
| fh->fh_rx_id = rx_fh->fh_rx_id; |
| fh->fh_seq_cnt = rx_fh->fh_seq_cnt; |
| fh->fh_r_ctl = FC_RCTL_BA_RJT; |
| fh->fh_type = FC_TYPE_BLS; |
| |
| /* |
| * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22). |
| * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT. |
| * Bits 9-8 are meaningful (retransmitted or unidirectional). |
| * Last ACK uses bits 7-6 (continue sequence), |
| * bits 5-4 are meaningful (what kind of ACK to use). |
| * Always set LAST_SEQ, END_SEQ. |
| */ |
| f_ctl = ntoh24(rx_fh->fh_f_ctl); |
| f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX | |
| FC_FC_END_CONN | FC_FC_SEQ_INIT | |
| FC_FC_RETX_SEQ | FC_FC_UNI_TX; |
| f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX; |
| f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ; |
| f_ctl &= ~FC_FC_FIRST_SEQ; |
| hton24(fh->fh_f_ctl, f_ctl); |
| |
| fr_sof(fp) = fc_sof_class(fr_sof(rx_fp)); |
| fr_eof(fp) = FC_EOF_T; |
| if (fc_sof_needs_ack(fr_sof(fp))) |
| fr_eof(fp) = FC_EOF_N; |
| |
| lport->tt.frame_send(lport, fp); |
| } |
| |
| /** |
| * fc_exch_recv_abts() - Handle an incoming ABTS |
| * @ep: The exchange the abort was on |
| * @rx_fp: The ABTS frame |
| * |
| * This would be for target mode usually, but could be due to lost |
| * FCP transfer ready, confirm or RRQ. We always handle this as an |
| * exchange abort, ignoring the parameter. |
| */ |
| static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp) |
| { |
| struct fc_frame *fp; |
| struct fc_ba_acc *ap; |
| struct fc_frame_header *fh; |
| struct fc_seq *sp; |
| |
| if (!ep) |
| goto reject; |
| spin_lock_bh(&ep->ex_lock); |
| if (ep->esb_stat & ESB_ST_COMPLETE) { |
| spin_unlock_bh(&ep->ex_lock); |
| goto reject; |
| } |
| if (!(ep->esb_stat & ESB_ST_REC_QUAL)) |
| fc_exch_hold(ep); /* hold for REC_QUAL */ |
| ep->esb_stat |= ESB_ST_ABNORMAL | ESB_ST_REC_QUAL; |
| fc_exch_timer_set_locked(ep, ep->r_a_tov); |
| |
| fp = fc_frame_alloc(ep->lp, sizeof(*ap)); |
| if (!fp) { |
| spin_unlock_bh(&ep->ex_lock); |
| goto free; |
| } |
| fh = fc_frame_header_get(fp); |
| ap = fc_frame_payload_get(fp, sizeof(*ap)); |
| memset(ap, 0, sizeof(*ap)); |
| sp = &ep->seq; |
| ap->ba_high_seq_cnt = htons(0xffff); |
| if (sp->ssb_stat & SSB_ST_RESP) { |
| ap->ba_seq_id = sp->id; |
| ap->ba_seq_id_val = FC_BA_SEQ_ID_VAL; |
| ap->ba_high_seq_cnt = fh->fh_seq_cnt; |
| ap->ba_low_seq_cnt = htons(sp->cnt); |
| } |
| sp = fc_seq_start_next_locked(sp); |
| spin_unlock_bh(&ep->ex_lock); |
| fc_seq_send_last(sp, fp, FC_RCTL_BA_ACC, FC_TYPE_BLS); |
| fc_frame_free(rx_fp); |
| return; |
| |
| reject: |
| fc_exch_send_ba_rjt(rx_fp, FC_BA_RJT_UNABLE, FC_BA_RJT_INV_XID); |
| free: |
| fc_frame_free(rx_fp); |
| } |
| |
| /** |
| * fc_seq_assign() - Assign exchange and sequence for incoming request |
| * @lport: The local port that received the request |
| * @fp: The request frame |
| * |
| * On success, the sequence pointer will be returned and also in fr_seq(@fp). |
| * A reference will be held on the exchange/sequence for the caller, which |
| * must call fc_seq_release(). |
| */ |
| static struct fc_seq *fc_seq_assign(struct fc_lport *lport, struct fc_frame *fp) |
| { |
| struct fc_exch_mgr_anchor *ema; |
| |
| WARN_ON(lport != fr_dev(fp)); |
| WARN_ON(fr_seq(fp)); |
| fr_seq(fp) = NULL; |
| |
| list_for_each_entry(ema, &lport->ema_list, ema_list) |
| if ((!ema->match || ema->match(fp)) && |
| fc_seq_lookup_recip(lport, ema->mp, fp) == FC_RJT_NONE) |
| break; |
| return fr_seq(fp); |
| } |
| |
| /** |
| * fc_seq_release() - Release the hold |
| * @sp: The sequence. |
| */ |
| static void fc_seq_release(struct fc_seq *sp) |
| { |
| fc_exch_release(fc_seq_exch(sp)); |
| } |
| |
| /** |
| * fc_exch_recv_req() - Handler for an incoming request |
| * @lport: The local port that received the request |
| * @mp: The EM that the exchange is on |
| * @fp: The request frame |
| * |
| * This is used when the other end is originating the exchange |
| * and the sequence. |
| */ |
| static void fc_exch_recv_req(struct fc_lport *lport, struct fc_exch_mgr *mp, |
| struct fc_frame *fp) |
| { |
| struct fc_frame_header *fh = fc_frame_header_get(fp); |
| struct fc_seq *sp = NULL; |
| struct fc_exch *ep = NULL; |
| enum fc_pf_rjt_reason reject; |
| |
| /* We can have the wrong fc_lport at this point with NPIV, which is a |
| * problem now that we know a new exchange needs to be allocated |
| */ |
| lport = fc_vport_id_lookup(lport, ntoh24(fh->fh_d_id)); |
| if (!lport) { |
| fc_frame_free(fp); |
| return; |
| } |
| fr_dev(fp) = lport; |
| |
| BUG_ON(fr_seq(fp)); /* XXX remove later */ |
| |
| /* |
| * If the RX_ID is 0xffff, don't allocate an exchange. |
| * The upper-level protocol may request one later, if needed. |
| */ |
| if (fh->fh_rx_id == htons(FC_XID_UNKNOWN)) |
| return lport->tt.lport_recv(lport, fp); |
| |
| reject = fc_seq_lookup_recip(lport, mp, fp); |
| if (reject == FC_RJT_NONE) { |
| sp = fr_seq(fp); /* sequence will be held */ |
| ep = fc_seq_exch(sp); |
| fc_seq_send_ack(sp, fp); |
| ep->encaps = fr_encaps(fp); |
| |
| /* |
| * Call the receive function. |
| * |
| * The receive function may allocate a new sequence |
| * over the old one, so we shouldn't change the |
| * sequence after this. |
| * |
| * The frame will be freed by the receive function. |
| * If new exch resp handler is valid then call that |
| * first. |
| */ |
| if (ep->resp) |
| ep->resp(sp, fp, ep->arg); |
| else |
| lport->tt.lport_recv(lport, fp); |
| fc_exch_release(ep); /* release from lookup */ |
| } else { |
| FC_LPORT_DBG(lport, "exch/seq lookup failed: reject %x\n", |
| reject); |
| fc_frame_free(fp); |
| } |
| } |
| |
| /** |
| * fc_exch_recv_seq_resp() - Handler for an incoming response where the other |
| * end is the originator of the sequence that is a |
| * response to our initial exchange |
| * @mp: The EM that the exchange is on |
| * @fp: The response frame |
| */ |
| static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp) |
| { |
| struct fc_frame_header *fh = fc_frame_header_get(fp); |
| struct fc_seq *sp; |
| struct fc_exch *ep; |
| enum fc_sof sof; |
| u32 f_ctl; |
| void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg); |
| void *ex_resp_arg; |
| int rc; |
| |
| ep = fc_exch_find(mp, ntohs(fh->fh_ox_id)); |
| if (!ep) { |
| atomic_inc(&mp->stats.xid_not_found); |
| goto out; |
| } |
| if (ep->esb_stat & ESB_ST_COMPLETE) { |
| atomic_inc(&mp->stats.xid_not_found); |
| goto rel; |
| } |
| if (ep->rxid == FC_XID_UNKNOWN) |
| ep->rxid = ntohs(fh->fh_rx_id); |
| if (ep->sid != 0 && ep->sid != ntoh24(fh->fh_d_id)) { |
| atomic_inc(&mp->stats.xid_not_found); |
| goto rel; |
| } |
| if (ep->did != ntoh24(fh->fh_s_id) && |
| ep->did != FC_FID_FLOGI) { |
| atomic_inc(&mp->stats.xid_not_found); |
| goto rel; |
| } |
| sof = fr_sof(fp); |
| sp = &ep->seq; |
| if (fc_sof_is_init(sof)) { |
| sp->ssb_stat |= SSB_ST_RESP; |
| sp->id = fh->fh_seq_id; |
| } else if (sp->id != fh->fh_seq_id) { |
| atomic_inc(&mp->stats.seq_not_found); |
| goto rel; |
| } |
| |
| f_ctl = ntoh24(fh->fh_f_ctl); |
| fr_seq(fp) = sp; |
| if (f_ctl & FC_FC_SEQ_INIT) |
| ep->esb_stat |= ESB_ST_SEQ_INIT; |
| |
| if (fc_sof_needs_ack(sof)) |
| fc_seq_send_ack(sp, fp); |
| resp = ep->resp; |
| ex_resp_arg = ep->arg; |
| |
| if (fh->fh_type != FC_TYPE_FCP && fr_eof(fp) == FC_EOF_T && |
| (f_ctl & (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) == |
| (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) { |
| spin_lock_bh(&ep->ex_lock); |
| resp = ep->resp; |
| rc = fc_exch_done_locked(ep); |
| WARN_ON(fc_seq_exch(sp) != ep); |
| spin_unlock_bh(&ep->ex_lock); |
| if (!rc) |
| fc_exch_delete(ep); |
| } |
| |
| /* |
| * Call the receive function. |
| * The sequence is held (has a refcnt) for us, |
| * but not for the receive function. |
| * |
| * The receive function may allocate a new sequence |
| * over the old one, so we shouldn't change the |
| * sequence after this. |
| * |
| * The frame will be freed by the receive function. |
| * If new exch resp handler is valid then call that |
| * first. |
| */ |
| if (resp) |
| resp(sp, fp, ex_resp_arg); |
| else |
| fc_frame_free(fp); |
| fc_exch_release(ep); |
| return; |
| rel: |
| fc_exch_release(ep); |
| out: |
| fc_frame_free(fp); |
| } |
| |
| /** |
| * fc_exch_recv_resp() - Handler for a sequence where other end is |
| * responding to our sequence |
| * @mp: The EM that the exchange is on |
| * @fp: The response frame |
| */ |
| static void fc_exch_recv_resp(struct fc_exch_mgr *mp, struct fc_frame *fp) |
| { |
| struct fc_seq *sp; |
| |
| sp = fc_seq_lookup_orig(mp, fp); /* doesn't hold sequence */ |
| |
| if (!sp) |
| atomic_inc(&mp->stats.xid_not_found); |
| else |
| atomic_inc(&mp->stats.non_bls_resp); |
| |
| fc_frame_free(fp); |
| } |
| |
| /** |
| * fc_exch_abts_resp() - Handler for a response to an ABT |
| * @ep: The exchange that the frame is on |
| * @fp: The response frame |
| * |
| * This response would be to an ABTS cancelling an exchange or sequence. |
| * The response can be either BA_ACC or BA_RJT |
| */ |
| static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp) |
| { |
| void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg); |
| void *ex_resp_arg; |
| struct fc_frame_header *fh; |
| struct fc_ba_acc *ap; |
| struct fc_seq *sp; |
| u16 low; |
| u16 high; |
| int rc = 1, has_rec = 0; |
| |
| fh = fc_frame_header_get(fp); |
| FC_EXCH_DBG(ep, "exch: BLS rctl %x - %s\n", fh->fh_r_ctl, |
| fc_exch_rctl_name(fh->fh_r_ctl)); |
| |
| if (cancel_delayed_work_sync(&ep->timeout_work)) |
| fc_exch_release(ep); /* release from pending timer hold */ |
| |
| spin_lock_bh(&ep->ex_lock); |
| switch (fh->fh_r_ctl) { |
| case FC_RCTL_BA_ACC: |
| ap = fc_frame_payload_get(fp, sizeof(*ap)); |
| if (!ap) |
| break; |
| |
| /* |
| * Decide whether to establish a Recovery Qualifier. |
| * We do this if there is a non-empty SEQ_CNT range and |
| * SEQ_ID is the same as the one we aborted. |
| */ |
| low = ntohs(ap->ba_low_seq_cnt); |
| high = ntohs(ap->ba_high_seq_cnt); |
| if ((ep->esb_stat & ESB_ST_REC_QUAL) == 0 && |
| (ap->ba_seq_id_val != FC_BA_SEQ_ID_VAL || |
| ap->ba_seq_id == ep->seq_id) && low != high) { |
| ep->esb_stat |= ESB_ST_REC_QUAL; |
| fc_exch_hold(ep); /* hold for recovery qualifier */ |
| has_rec = 1; |
| } |
| break; |
| case FC_RCTL_BA_RJT: |
| break; |
| default: |
| break; |
| } |
| |
| resp = ep->resp; |
| ex_resp_arg = ep->arg; |
| |
| /* do we need to do some other checks here. Can we reuse more of |
| * fc_exch_recv_seq_resp |
| */ |
| sp = &ep->seq; |
| /* |
| * do we want to check END_SEQ as well as LAST_SEQ here? |
| */ |
| if (ep->fh_type != FC_TYPE_FCP && |
| ntoh24(fh->fh_f_ctl) & FC_FC_LAST_SEQ) |
| rc = fc_exch_done_locked(ep); |
| spin_unlock_bh(&ep->ex_lock); |
| if (!rc) |
| fc_exch_delete(ep); |
| |
| if (resp) |
| resp(sp, fp, ex_resp_arg); |
| else |
| fc_frame_free(fp); |
| |
| if (has_rec) |
| fc_exch_timer_set(ep, ep->r_a_tov); |
| |
| } |
| |
| /** |
| * fc_exch_recv_bls() - Handler for a BLS sequence |
| * @mp: The EM that the exchange is on |
| * @fp: The request frame |
| * |
| * The BLS frame is always a sequence initiated by the remote side. |
| * We may be either the originator or recipient of the exchange. |
| */ |
| static void fc_exch_recv_bls(struct fc_exch_mgr *mp, struct fc_frame *fp) |
| { |
| struct fc_frame_header *fh; |
| struct fc_exch *ep; |
| u32 f_ctl; |
| |
| fh = fc_frame_header_get(fp); |
| f_ctl = ntoh24(fh->fh_f_ctl); |
| fr_seq(fp) = NULL; |
| |
| ep = fc_exch_find(mp, (f_ctl & FC_FC_EX_CTX) ? |
| ntohs(fh->fh_ox_id) : ntohs(fh->fh_rx_id)); |
| if (ep && (f_ctl & FC_FC_SEQ_INIT)) { |
| spin_lock_bh(&ep->ex_lock); |
| ep->esb_stat |= ESB_ST_SEQ_INIT; |
| spin_unlock_bh(&ep->ex_lock); |
| } |
| if (f_ctl & FC_FC_SEQ_CTX) { |
| /* |
| * A response to a sequence we initiated. |
| * This should only be ACKs for class 2 or F. |
| */ |
| switch (fh->fh_r_ctl) { |
| case FC_RCTL_ACK_1: |
| case FC_RCTL_ACK_0: |
| break; |
| default: |
| FC_EXCH_DBG(ep, "BLS rctl %x - %s received", |
| fh->fh_r_ctl, |
| fc_exch_rctl_name(fh->fh_r_ctl)); |
| break; |
| } |
| fc_frame_free(fp); |
| } else { |
| switch (fh->fh_r_ctl) { |
| case FC_RCTL_BA_RJT: |
| case FC_RCTL_BA_ACC: |
| if (ep) |
| fc_exch_abts_resp(ep, fp); |
| else |
| fc_frame_free(fp); |
| break; |
| case FC_RCTL_BA_ABTS: |
| fc_exch_recv_abts(ep, fp); |
| break; |
| default: /* ignore junk */ |
| fc_frame_free(fp); |
| break; |
| } |
| } |
| if (ep) |
| fc_exch_release(ep); /* release hold taken by fc_exch_find */ |
| } |
| |
| /** |
| * fc_seq_ls_acc() - Accept sequence with LS_ACC |
| * @rx_fp: The received frame, not freed here. |
| * |
| * If this fails due to allocation or transmit congestion, assume the |
| * originator will repeat the sequence. |
| */ |
| static void fc_seq_ls_acc(struct fc_frame *rx_fp) |
| { |
| struct fc_lport *lport; |
| struct fc_els_ls_acc *acc; |
| struct fc_frame *fp; |
| |
| lport = fr_dev(rx_fp); |
| fp = fc_frame_alloc(lport, sizeof(*acc)); |
| if (!fp) |
| return; |
| acc = fc_frame_payload_get(fp, sizeof(*acc)); |
| memset(acc, 0, sizeof(*acc)); |
| acc->la_cmd = ELS_LS_ACC; |
| fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0); |
| lport->tt.frame_send(lport, fp); |
| } |
| |
| /** |
| * fc_seq_ls_rjt() - Reject a sequence with ELS LS_RJT |
| * @rx_fp: The received frame, not freed here. |
| * @reason: The reason the sequence is being rejected |
| * @explan: The explanation for the rejection |
| * |
| * If this fails due to allocation or transmit congestion, assume the |
| * originator will repeat the sequence. |
| */ |
| static void fc_seq_ls_rjt(struct fc_frame *rx_fp, enum fc_els_rjt_reason reason, |
| enum fc_els_rjt_explan explan) |
| { |
| struct fc_lport *lport; |
| struct fc_els_ls_rjt *rjt; |
| struct fc_frame *fp; |
| |
| lport = fr_dev(rx_fp); |
| fp = fc_frame_alloc(lport, sizeof(*rjt)); |
| if (!fp) |
| return; |
| rjt = fc_frame_payload_get(fp, sizeof(*rjt)); |
| memset(rjt, 0, sizeof(*rjt)); |
| rjt->er_cmd = ELS_LS_RJT; |
| rjt->er_reason = reason; |
| rjt->er_explan = explan; |
| fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0); |
| lport->tt.frame_send(lport, fp); |
| } |
| |
| /** |
| * fc_exch_reset() - Reset an exchange |
| * @ep: The exchange to be reset |
| */ |
| static void fc_exch_reset(struct fc_exch *ep) |
| { |
| struct fc_seq *sp; |
| void (*resp)(struct fc_seq *, struct fc_frame *, void *); |
| void *arg; |
| int rc = 1; |
| |
| spin_lock_bh(&ep->ex_lock); |
| ep->state |= FC_EX_RST_CLEANUP; |
| if (cancel_delayed_work(&ep->timeout_work)) |
| atomic_dec(&ep->ex_refcnt); /* drop hold for timer */ |
| resp = ep->resp; |
| ep->resp = NULL; |
| if (ep->esb_stat & ESB_ST_REC_QUAL) |
| atomic_dec(&ep->ex_refcnt); /* drop hold for rec_qual */ |
| ep->esb_stat &= ~ESB_ST_REC_QUAL; |
| arg = ep->arg; |
| sp = &ep->seq; |
| rc = fc_exch_done_locked(ep); |
| spin_unlock_bh(&ep->ex_lock); |
| if (!rc) |
| fc_exch_delete(ep); |
| |
| if (resp) |
| resp(sp, ERR_PTR(-FC_EX_CLOSED), arg); |
| } |
| |
| /** |
| * fc_exch_pool_reset() - Reset a per cpu exchange pool |
| * @lport: The local port that the exchange pool is on |
| * @pool: The exchange pool to be reset |
| * @sid: The source ID |
| * @did: The destination ID |
| * |
| * Resets a per cpu exches pool, releasing all of its sequences |
| * and exchanges. If sid is non-zero then reset only exchanges |
| * we sourced from the local port's FID. If did is non-zero then |
| * only reset exchanges destined for the local port's FID. |
| */ |
| static void fc_exch_pool_reset(struct fc_lport *lport, |
| struct fc_exch_pool *pool, |
| u32 sid, u32 did) |
| { |
| struct fc_exch *ep; |
| struct fc_exch *next; |
| |
| spin_lock_bh(&pool->lock); |
| restart: |
| list_for_each_entry_safe(ep, next, &pool->ex_list, ex_list) { |
| if ((lport == ep->lp) && |
| (sid == 0 || sid == ep->sid) && |
| (did == 0 || did == ep->did)) { |
| fc_exch_hold(ep); |
| spin_unlock_bh(&pool->lock); |
| |
| fc_exch_reset(ep); |
| |
| fc_exch_release(ep); |
| spin_lock_bh(&pool->lock); |
| |
| /* |
| * must restart loop incase while lock |
| * was down multiple eps were released. |
| */ |
| goto restart; |
| } |
| } |
| spin_unlock_bh(&pool->lock); |
| } |
| |
| /** |
| * fc_exch_mgr_reset() - Reset all EMs of a local port |
| * @lport: The local port whose EMs are to be reset |
| * @sid: The source ID |
| * @did: The destination ID |
| * |
| * Reset all EMs associated with a given local port. Release all |
| * sequences and exchanges. If sid is non-zero then reset only the |
| * exchanges sent from the local port's FID. If did is non-zero then |
| * reset only exchanges destined for the local port's FID. |
| */ |
| void fc_exch_mgr_reset(struct fc_lport *lport, u32 sid, u32 did) |
| { |
| struct fc_exch_mgr_anchor *ema; |
| unsigned int cpu; |
| |
| list_for_each_entry(ema, &lport->ema_list, ema_list) { |
| for_each_possible_cpu(cpu) |
| fc_exch_pool_reset(lport, |
| per_cpu_ptr(ema->mp->pool, cpu), |
| sid, did); |
| } |
| } |
| EXPORT_SYMBOL(fc_exch_mgr_reset); |
| |
| /** |
| * fc_exch_lookup() - find an exchange |
| * @lport: The local port |
| * @xid: The exchange ID |
| * |
| * Returns exchange pointer with hold for caller, or NULL if not found. |
| */ |
| static struct fc_exch *fc_exch_lookup(struct fc_lport *lport, u32 xid) |
| { |
| struct fc_exch_mgr_anchor *ema; |
| |
| list_for_each_entry(ema, &lport->ema_list, ema_list) |
| if (ema->mp->min_xid <= xid && xid <= ema->mp->max_xid) |
| return fc_exch_find(ema->mp, xid); |
| return NULL; |
| } |
| |
| /** |
| * fc_exch_els_rec() - Handler for ELS REC (Read Exchange Concise) requests |
| * @rfp: The REC frame, not freed here. |
| * |
| * Note that the requesting port may be different than the S_ID in the request. |
| */ |
| static void fc_exch_els_rec(struct fc_frame *rfp) |
| { |
| struct fc_lport *lport; |
| struct fc_frame *fp; |
| struct fc_exch *ep; |
| struct fc_els_rec *rp; |
| struct fc_els_rec_acc *acc; |
| enum fc_els_rjt_reason reason = ELS_RJT_LOGIC; |
| enum fc_els_rjt_explan explan; |
| u32 sid; |
| u16 rxid; |
| u16 oxid; |
| |
| lport = fr_dev(rfp); |
| rp = fc_frame_payload_get(rfp, sizeof(*rp)); |
| explan = ELS_EXPL_INV_LEN; |
| if (!rp) |
| goto reject; |
| sid = ntoh24(rp->rec_s_id); |
| rxid = ntohs(rp->rec_rx_id); |
| oxid = ntohs(rp->rec_ox_id); |
| |
| ep = fc_exch_lookup(lport, |
| sid == fc_host_port_id(lport->host) ? oxid : rxid); |
| explan = ELS_EXPL_OXID_RXID; |
| if (!ep) |
| goto reject; |
| if (ep->oid != sid || oxid != ep->oxid) |
| goto rel; |
| if (rxid != FC_XID_UNKNOWN && rxid != ep->rxid) |
| goto rel; |
| fp = fc_frame_alloc(lport, sizeof(*acc)); |
| if (!fp) |
| goto out; |
| |
| acc = fc_frame_payload_get(fp, sizeof(*acc)); |
| memset(acc, 0, sizeof(*acc)); |
| acc->reca_cmd = ELS_LS_ACC; |
| acc->reca_ox_id = rp->rec_ox_id; |
| memcpy(acc->reca_ofid, rp->rec_s_id, 3); |
| acc->reca_rx_id = htons(ep->rxid); |
| if (ep->sid == ep->oid) |
| hton24(acc->reca_rfid, ep->did); |
| else |
| hton24(acc->reca_rfid, ep->sid); |
| acc->reca_fc4value = htonl(ep->seq.rec_data); |
| acc->reca_e_stat = htonl(ep->esb_stat & (ESB_ST_RESP | |
| ESB_ST_SEQ_INIT | |
| ESB_ST_COMPLETE)); |
| fc_fill_reply_hdr(fp, rfp, FC_RCTL_ELS_REP, 0); |
| lport->tt.frame_send(lport, fp); |
| out: |
| fc_exch_release(ep); |
| return; |
| |
| rel: |
| fc_exch_release(ep); |
| reject: |
| fc_seq_ls_rjt(rfp, reason, explan); |
| } |
| |
| /** |
| * fc_exch_rrq_resp() - Handler for RRQ responses |
| * @sp: The sequence that the RRQ is on |
| * @fp: The RRQ frame |
| * @arg: The exchange that the RRQ is on |
| * |
| * TODO: fix error handler. |
| */ |
| static void fc_exch_rrq_resp(struct fc_seq *sp, struct fc_frame *fp, void *arg) |
| { |
| struct fc_exch *aborted_ep = arg; |
| unsigned int op; |
| |
| if (IS_ERR(fp)) { |
| int err = PTR_ERR(fp); |
| |
| if (err == -FC_EX_CLOSED || err == -FC_EX_TIMEOUT) |
| goto cleanup; |
| FC_EXCH_DBG(aborted_ep, "Cannot process RRQ, " |
| "frame error %d\n", err); |
| return; |
| } |
| |
| op = fc_frame_payload_op(fp); |
| fc_frame_free(fp); |
| |
| switch (op) { |
| case ELS_LS_RJT: |
| FC_EXCH_DBG(aborted_ep, "LS_RJT for RRQ"); |
| /* fall through */ |
| case ELS_LS_ACC: |
| goto cleanup; |
| default: |
| FC_EXCH_DBG(aborted_ep, "unexpected response op %x " |
| "for RRQ", op); |
| return; |
| } |
| |
| cleanup: |
| fc_exch_done(&aborted_ep->seq); |
| /* drop hold for rec qual */ |
| fc_exch_release(aborted_ep); |
| } |
| |
| |
| /** |
| * fc_exch_seq_send() - Send a frame using a new exchange and sequence |
| * @lport: The local port to send the frame on |
| * @fp: The frame to be sent |
| * @resp: The response handler for this request |
| * @destructor: The destructor for the exchange |
| * @arg: The argument to be passed to the response handler |
| * @timer_msec: The timeout period for the exchange |
| * |
| * The frame pointer with some of the header's fields must be |
| * filled before calling this routine, those fields are: |
| * |
| * - routing control |
| * - FC port did |
| * - FC port sid |
| * - FC header type |
| * - frame control |
| * - parameter or relative offset |
| */ |
| static struct fc_seq *fc_exch_seq_send(struct fc_lport *lport, |
| struct fc_frame *fp, |
| void (*resp)(struct fc_seq *, |
| struct fc_frame *fp, |
| void *arg), |
| void (*destructor)(struct fc_seq *, |
| void *), |
| void *arg, u32 timer_msec) |
| { |
| struct fc_exch *ep; |
| struct fc_seq *sp = NULL; |
| struct fc_frame_header *fh; |
| int rc = 1; |
| |
| ep = fc_exch_alloc(lport, fp); |
| if (!ep) { |
| fc_frame_free(fp); |
| return NULL; |
| } |
| ep->esb_stat |= ESB_ST_SEQ_INIT; |
| fh = fc_frame_header_get(fp); |
| fc_exch_set_addr(ep, ntoh24(fh->fh_s_id), ntoh24(fh->fh_d_id)); |
| ep->resp = resp; |
| ep->destructor = destructor; |
| ep->arg = arg; |
| ep->r_a_tov = FC_DEF_R_A_TOV; |
| ep->lp = lport; |
| sp = &ep->seq; |
| |
| ep->fh_type = fh->fh_type; /* save for possbile timeout handling */ |
| ep->f_ctl = ntoh24(fh->fh_f_ctl); |
| fc_exch_setup_hdr(ep, fp, ep->f_ctl); |
| sp->cnt++; |
| |
| if (ep->xid <= lport->lro_xid && fh->fh_r_ctl == FC_RCTL_DD_UNSOL_CMD) |
| fc_fcp_ddp_setup(fr_fsp(fp), ep->xid); |
| |
| if (unlikely(lport->tt.frame_send(lport, fp))) |
| goto err; |
| |
| if (timer_msec) |
| fc_exch_timer_set_locked(ep, timer_msec); |
| ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not first seq */ |
| |
| if (ep->f_ctl & FC_FC_SEQ_INIT) |
| ep->esb_stat &= ~ESB_ST_SEQ_INIT; |
| spin_unlock_bh(&ep->ex_lock); |
| return sp; |
| err: |
| fc_fcp_ddp_done(fr_fsp(fp)); |
| rc = fc_exch_done_locked(ep); |
| spin_unlock_bh(&ep->ex_lock); |
| if (!rc) |
| fc_exch_delete(ep); |
| return NULL; |
| } |
| |
| /** |
| * fc_exch_rrq() - Send an ELS RRQ (Reinstate Recovery Qualifier) command |
| * @ep: The exchange to send the RRQ on |
| * |
| * This tells the remote port to stop blocking the use of |
| * the exchange and the seq_cnt range. |
| */ |
| static void fc_exch_rrq(struct fc_exch *ep) |
| { |
| struct fc_lport *lport; |
| struct fc_els_rrq *rrq; |
| struct fc_frame *fp; |
| u32 did; |
| |
| lport = ep->lp; |
| |
| fp = fc_frame_alloc(lport, sizeof(*rrq)); |
| if (!fp) |
| goto retry; |
| |
| rrq = fc_frame_payload_get(fp, sizeof(*rrq)); |
| memset(rrq, 0, sizeof(*rrq)); |
| rrq->rrq_cmd = ELS_RRQ; |
| hton24(rrq->rrq_s_id, ep->sid); |
| rrq->rrq_ox_id = htons(ep->oxid); |
| rrq->rrq_rx_id = htons(ep->rxid); |
| |
| did = ep->did; |
| if (ep->esb_stat & ESB_ST_RESP) |
| did = ep->sid; |
| |
| fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, did, |
| lport->port_id, FC_TYPE_ELS, |
| FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0); |
| |
| if (fc_exch_seq_send(lport, fp, fc_exch_rrq_resp, NULL, ep, |
| lport->e_d_tov)) |
| return; |
| |
| retry: |
| spin_lock_bh(&ep->ex_lock); |
| if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) { |
| spin_unlock_bh(&ep->ex_lock); |
| /* drop hold for rec qual */ |
| fc_exch_release(ep); |
| return; |
| } |
| ep->esb_stat |= ESB_ST_REC_QUAL; |
| fc_exch_timer_set_locked(ep, ep->r_a_tov); |
| spin_unlock_bh(&ep->ex_lock); |
| } |
| |
| /** |
| * fc_exch_els_rrq() - Handler for ELS RRQ (Reset Recovery Qualifier) requests |
| * @fp: The RRQ frame, not freed here. |
| */ |
| static void fc_exch_els_rrq(struct fc_frame *fp) |
| { |
| struct fc_lport *lport; |
| struct fc_exch *ep = NULL; /* request or subject exchange */ |
| struct fc_els_rrq *rp; |
| u32 sid; |
| u16 xid; |
| enum fc_els_rjt_explan explan; |
| |
| lport = fr_dev(fp); |
| rp = fc_frame_payload_get(fp, sizeof(*rp)); |
| explan = ELS_EXPL_INV_LEN; |
| if (!rp) |
| goto reject; |
| |
| /* |
| * lookup subject exchange. |
| */ |
| sid = ntoh24(rp->rrq_s_id); /* subject source */ |
| xid = fc_host_port_id(lport->host) == sid ? |
| ntohs(rp->rrq_ox_id) : ntohs(rp->rrq_rx_id); |
| ep = fc_exch_lookup(lport, xid); |
| explan = ELS_EXPL_OXID_RXID; |
| if (!ep) |
| goto reject; |
| spin_lock_bh(&ep->ex_lock); |
| if (ep->oxid != ntohs(rp->rrq_ox_id)) |
| goto unlock_reject; |
| if (ep->rxid != ntohs(rp->rrq_rx_id) && |
| ep->rxid != FC_XID_UNKNOWN) |
| goto unlock_reject; |
| explan = ELS_EXPL_SID; |
| if (ep->sid != sid) |
| goto unlock_reject; |
| |
| /* |
| * Clear Recovery Qualifier state, and cancel timer if complete. |
| */ |
| if (ep->esb_stat & ESB_ST_REC_QUAL) { |
| ep->esb_stat &= ~ESB_ST_REC_QUAL; |
| atomic_dec(&ep->ex_refcnt); /* drop hold for rec qual */ |
| } |
| if (ep->esb_stat & ESB_ST_COMPLETE) { |
| if (cancel_delayed_work(&ep->timeout_work)) |
| atomic_dec(&ep->ex_refcnt); /* drop timer hold */ |
| } |
| |
| spin_unlock_bh(&ep->ex_lock); |
| |
| /* |
| * Send LS_ACC. |
| */ |
| fc_seq_ls_acc(fp); |
| goto out; |
| |
| unlock_reject: |
| spin_unlock_bh(&ep->ex_lock); |
| reject: |
| fc_seq_ls_rjt(fp, ELS_RJT_LOGIC, explan); |
| out: |
| if (ep) |
| fc_exch_release(ep); /* drop hold from fc_exch_find */ |
| } |
| |
| /** |
| * fc_exch_mgr_add() - Add an exchange manager to a local port's list of EMs |
| * @lport: The local port to add the exchange manager to |
| * @mp: The exchange manager to be added to the local port |
| * @match: The match routine that indicates when this EM should be used |
| */ |
| struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *lport, |
| struct fc_exch_mgr *mp, |
| bool (*match)(struct fc_frame *)) |
| { |
| struct fc_exch_mgr_anchor *ema; |
| |
| ema = kmalloc(sizeof(*ema), GFP_ATOMIC); |
| if (!ema) |
| return ema; |
| |
| ema->mp = mp; |
| ema->match = match; |
| /* add EM anchor to EM anchors list */ |
| list_add_tail(&ema->ema_list, &lport->ema_list); |
| kref_get(&mp->kref); |
| return ema; |
| } |
| EXPORT_SYMBOL(fc_exch_mgr_add); |
| |
| /** |
| * fc_exch_mgr_destroy() - Destroy an exchange manager |
| * @kref: The reference to the EM to be destroyed |
| */ |
| static void fc_exch_mgr_destroy(struct kref *kref) |
| { |
| struct fc_exch_mgr *mp = container_of(kref, struct fc_exch_mgr, kref); |
| |
| mempool_destroy(mp->ep_pool); |
| free_percpu(mp->pool); |
| kfree(mp); |
| } |
| |
| /** |
| * fc_exch_mgr_del() - Delete an EM from a local port's list |
| * @ema: The exchange manager anchor identifying the EM to be deleted |
| */ |
| void fc_exch_mgr_del(struct fc_exch_mgr_anchor *ema) |
| { |
| /* remove EM anchor from EM anchors list */ |
| list_del(&ema->ema_list); |
| kref_put(&ema->mp->kref, fc_exch_mgr_destroy); |
| kfree(ema); |
| } |
| EXPORT_SYMBOL(fc_exch_mgr_del); |
| |
| /** |
| * fc_exch_mgr_list_clone() - Share all exchange manager objects |
| * @src: Source lport to clone exchange managers from |
| * @dst: New lport that takes references to all the exchange managers |
| */ |
| int fc_exch_mgr_list_clone(struct fc_lport *src, struct fc_lport *dst) |
| { |
| struct fc_exch_mgr_anchor *ema, *tmp; |
| |
| list_for_each_entry(ema, &src->ema_list, ema_list) { |
| if (!fc_exch_mgr_add(dst, ema->mp, ema->match)) |
| goto err; |
| } |
| return 0; |
| err: |
| list_for_each_entry_safe(ema, tmp, &dst->ema_list, ema_list) |
| fc_exch_mgr_del(ema); |
| return -ENOMEM; |
| } |
| EXPORT_SYMBOL(fc_exch_mgr_list_clone); |
| |
| /** |
| * fc_exch_mgr_alloc() - Allocate an exchange manager |
| * @lport: The local port that the new EM will be associated with |
| * @class: The default FC class for new exchanges |
| * @min_xid: The minimum XID for exchanges from the new EM |
| * @max_xid: The maximum XID for exchanges from the new EM |
| * @match: The match routine for the new EM |
| */ |
| struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lport, |
| enum fc_class class, |
| u16 min_xid, u16 max_xid, |
| bool (*match)(struct fc_frame *)) |
| { |
| struct fc_exch_mgr *mp; |
| u16 pool_exch_range; |
| size_t pool_size; |
| unsigned int cpu; |
| struct fc_exch_pool *pool; |
| |
| if (max_xid <= min_xid || max_xid == FC_XID_UNKNOWN || |
| (min_xid & fc_cpu_mask) != 0) { |
| FC_LPORT_DBG(lport, "Invalid min_xid 0x:%x and max_xid 0x:%x\n", |
| min_xid, max_xid); |
| return NULL; |
| } |
| |
| /* |
| * allocate memory for EM |
| */ |
| mp = kzalloc(sizeof(struct fc_exch_mgr), GFP_ATOMIC); |
| if (!mp) |
| return NULL; |
| |
| mp->class = class; |
| /* adjust em exch xid range for offload */ |
| mp->min_xid = min_xid; |
| mp->max_xid = max_xid; |
| |
| mp->ep_pool = mempool_create_slab_pool(2, fc_em_cachep); |
| if (!mp->ep_pool) |
| goto free_mp; |
| |
| /* |
| * Setup per cpu exch pool with entire exchange id range equally |
| * divided across all cpus. The exch pointers array memory is |
| * allocated for exch range per pool. |
| */ |
| pool_exch_range = (mp->max_xid - mp->min_xid + 1) / (fc_cpu_mask + 1); |
| mp->pool_max_index = pool_exch_range - 1; |
| |
| /* |
| * Allocate and initialize per cpu exch pool |
| */ |
| pool_size = sizeof(*pool) + pool_exch_range * sizeof(struct fc_exch *); |
| mp->pool = __alloc_percpu(pool_size, __alignof__(struct fc_exch_pool)); |
| if (!mp->pool) |
| goto free_mempool; |
| for_each_possible_cpu(cpu) { |
| pool = per_cpu_ptr(mp->pool, cpu); |
| pool->left = FC_XID_UNKNOWN; |
| pool->right = FC_XID_UNKNOWN; |
| spin_lock_init(&pool->lock); |
| INIT_LIST_HEAD(&pool->ex_list); |
| } |
| |
| kref_init(&mp->kref); |
| if (!fc_exch_mgr_add(lport, mp, match)) { |
| free_percpu(mp->pool); |
| goto free_mempool; |
| } |
| |
| /* |
| * Above kref_init() sets mp->kref to 1 and then |
| * call to fc_exch_mgr_add incremented mp->kref again, |
| * so adjust that extra increment. |
| */ |
| kref_put(&mp->kref, fc_exch_mgr_destroy); |
| return mp; |
| |
| free_mempool: |
| mempool_destroy(mp->ep_pool); |
| free_mp: |
| kfree(mp); |
| return NULL; |
| } |
| EXPORT_SYMBOL(fc_exch_mgr_alloc); |
| |
| /** |
| * fc_exch_mgr_free() - Free all exchange managers on a local port |
| * @lport: The local port whose EMs are to be freed |
| */ |
| void fc_exch_mgr_free(struct fc_lport *lport) |
| { |
| struct fc_exch_mgr_anchor *ema, *next; |
| |
| flush_workqueue(fc_exch_workqueue); |
| list_for_each_entry_safe(ema, next, &lport->ema_list, ema_list) |
| fc_exch_mgr_del(ema); |
| } |
| EXPORT_SYMBOL(fc_exch_mgr_free); |
| |
| /** |
| * fc_find_ema() - Lookup and return appropriate Exchange Manager Anchor depending |
| * upon 'xid'. |
| * @f_ctl: f_ctl |
| * @lport: The local port the frame was received on |
| * @fh: The received frame header |
| */ |
| static struct fc_exch_mgr_anchor *fc_find_ema(u32 f_ctl, |
| struct fc_lport *lport, |
| struct fc_frame_header *fh) |
| { |
| struct fc_exch_mgr_anchor *ema; |
| u16 xid; |
| |
| if (f_ctl & FC_FC_EX_CTX) |
| xid = ntohs(fh->fh_ox_id); |
| else { |
| xid = ntohs(fh->fh_rx_id); |
| if (xid == FC_XID_UNKNOWN) |
| return list_entry(lport->ema_list.prev, |
| typeof(*ema), ema_list); |
| } |
| |
| list_for_each_entry(ema, &lport->ema_list, ema_list) { |
| if ((xid >= ema->mp->min_xid) && |
| (xid <= ema->mp->max_xid)) |
| return ema; |
| } |
| return NULL; |
| } |
| /** |
| * fc_exch_recv() - Handler for received frames |
| * @lport: The local port the frame was received on |
| * @fp: The received frame |
| */ |
| void fc_exch_recv(struct fc_lport *lport, struct fc_frame *fp) |
| { |
| struct fc_frame_header *fh = fc_frame_header_get(fp); |
| struct fc_exch_mgr_anchor *ema; |
| u32 f_ctl; |
| |
| /* lport lock ? */ |
| if (!lport || lport->state == LPORT_ST_DISABLED) { |
| FC_LPORT_DBG(lport, "Receiving frames for an lport that " |
| "has not been initialized correctly\n"); |
| fc_frame_free(fp); |
| return; |
| } |
| |
| f_ctl = ntoh24(fh->fh_f_ctl); |
| ema = fc_find_ema(f_ctl, lport, fh); |
| if (!ema) { |
| FC_LPORT_DBG(lport, "Unable to find Exchange Manager Anchor," |
| "fc_ctl <0x%x>, xid <0x%x>\n", |
| f_ctl, |
| (f_ctl & FC_FC_EX_CTX) ? |
| ntohs(fh->fh_ox_id) : |
| ntohs(fh->fh_rx_id)); |
| fc_frame_free(fp); |
| return; |
| } |
| |
| /* |
| * If frame is marked invalid, just drop it. |
| */ |
| switch (fr_eof(fp)) { |
| case FC_EOF_T: |
| if (f_ctl & FC_FC_END_SEQ) |
| skb_trim(fp_skb(fp), fr_len(fp) - FC_FC_FILL(f_ctl)); |
| /* fall through */ |
| case FC_EOF_N: |
| if (fh->fh_type == FC_TYPE_BLS) |
| fc_exch_recv_bls(ema->mp, fp); |
| else if ((f_ctl & (FC_FC_EX_CTX | FC_FC_SEQ_CTX)) == |
| FC_FC_EX_CTX) |
| fc_exch_recv_seq_resp(ema->mp, fp); |
| else if (f_ctl & FC_FC_SEQ_CTX) |
| fc_exch_recv_resp(ema->mp, fp); |
| else /* no EX_CTX and no SEQ_CTX */ |
| fc_exch_recv_req(lport, ema->mp, fp); |
| break; |
| default: |
| FC_LPORT_DBG(lport, "dropping invalid frame (eof %x)", |
| fr_eof(fp)); |
| fc_frame_free(fp); |
| } |
| } |
| EXPORT_SYMBOL(fc_exch_recv); |
| |
| /** |
| * fc_exch_init() - Initialize the exchange layer for a local port |
| * @lport: The local port to initialize the exchange layer for |
| */ |
| int fc_exch_init(struct fc_lport *lport) |
| { |
| if (!lport->tt.seq_start_next) |
| lport->tt.seq_start_next = fc_seq_start_next; |
| |
| if (!lport->tt.seq_set_resp) |
| lport->tt.seq_set_resp = fc_seq_set_resp; |
| |
| if (!lport->tt.exch_seq_send) |
| lport->tt.exch_seq_send = fc_exch_seq_send; |
| |
| if (!lport->tt.seq_send) |
| lport->tt.seq_send = fc_seq_send; |
| |
| if (!lport->tt.seq_els_rsp_send) |
| lport->tt.seq_els_rsp_send = fc_seq_els_rsp_send; |
| |
| if (!lport->tt.exch_done) |
| lport->tt.exch_done = fc_exch_done; |
| |
| if (!lport->tt.exch_mgr_reset) |
| lport->tt.exch_mgr_reset = fc_exch_mgr_reset; |
| |
| if (!lport->tt.seq_exch_abort) |
| lport->tt.seq_exch_abort = fc_seq_exch_abort; |
| |
| if (!lport->tt.seq_assign) |
| lport->tt.seq_assign = fc_seq_assign; |
| |
| if (!lport->tt.seq_release) |
| lport->tt.seq_release = fc_seq_release; |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(fc_exch_init); |
| |
| /** |
| * fc_setup_exch_mgr() - Setup an exchange manager |
| */ |
| int fc_setup_exch_mgr(void) |
| { |
| fc_em_cachep = kmem_cache_create("libfc_em", sizeof(struct fc_exch), |
| 0, SLAB_HWCACHE_ALIGN, NULL); |
| if (!fc_em_cachep) |
| return -ENOMEM; |
| |
| /* |
| * Initialize fc_cpu_mask and fc_cpu_order. The |
| * fc_cpu_mask is set for nr_cpu_ids rounded up |
| * to order of 2's * power and order is stored |
| * in fc_cpu_order as this is later required in |
| * mapping between an exch id and exch array index |
| * in per cpu exch pool. |
| * |
| * This round up is required to align fc_cpu_mask |
| * to exchange id's lower bits such that all incoming |
| * frames of an exchange gets delivered to the same |
| * cpu on which exchange originated by simple bitwise |
| * AND operation between fc_cpu_mask and exchange id. |
| */ |
| fc_cpu_mask = 1; |
| fc_cpu_order = 0; |
| while (fc_cpu_mask < nr_cpu_ids) { |
| fc_cpu_mask <<= 1; |
| fc_cpu_order++; |
| } |
| fc_cpu_mask--; |
| |
| fc_exch_workqueue = create_singlethread_workqueue("fc_exch_workqueue"); |
| if (!fc_exch_workqueue) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| /** |
| * fc_destroy_exch_mgr() - Destroy an exchange manager |
| */ |
| void fc_destroy_exch_mgr(void) |
| { |
| destroy_workqueue(fc_exch_workqueue); |
| kmem_cache_destroy(fc_em_cachep); |
| } |