return 0;
}
+/*
+ * fcoe_oem_match() - match for read types IO
+ * @fp: the fc_frame for new IO.
+ *
+ * Returns : true for read types IO, otherwise returns false.
+ */
+bool fcoe_oem_match(struct fc_frame *fp)
+{
+ return fc_fcp_is_read(fr_fsp(fp));
+}
+
/**
* fcoe_em_config() - allocates em for this lport
* @lp: the port that em is to allocated for
*/
static inline int fcoe_em_config(struct fc_lport *lp)
{
- if (!fc_exch_mgr_alloc(lp, FC_CLASS_3, FCOE_MIN_XID,
- FCOE_MAX_XID, NULL))
+ struct fcoe_softc *fc = lport_priv(lp);
+ struct fcoe_softc *oldfc = NULL;
+ u16 min_xid = FCOE_MIN_XID;
+ u16 max_xid = FCOE_MAX_XID;
+
+ /*
+ * Check if need to allocate an em instance for
+ * offload exchange ids to be shared across all VN_PORTs/lport.
+ */
+ if (!lp->lro_enabled || !lp->lro_xid || (lp->lro_xid >= max_xid)) {
+ lp->lro_xid = 0;
+ goto skip_oem;
+ }
+
+ /*
+ * Reuse existing offload em instance in case
+ * it is already allocated on phys_dev.
+ */
+ list_for_each_entry(oldfc, &fcoe_hostlist, list) {
+ if (oldfc->phys_dev == fc->phys_dev) {
+ fc->oem = oldfc->oem;
+ break;
+ }
+ }
+
+ if (fc->oem) {
+ if (!fc_exch_mgr_add(lp, fc->oem, fcoe_oem_match)) {
+ printk(KERN_ERR "fcoe_em_config: failed to add "
+ "offload em:%p on interface:%s\n",
+ fc->oem, fc->real_dev->name);
+ return -ENOMEM;
+ }
+ } else {
+ fc->oem = fc_exch_mgr_alloc(lp, FC_CLASS_3,
+ FCOE_MIN_XID, lp->lro_xid,
+ fcoe_oem_match);
+ if (!fc->oem) {
+ printk(KERN_ERR "fcoe_em_config: failed to allocate "
+ "em for offload exches on interface:%s\n",
+ fc->real_dev->name);
+ return -ENOMEM;
+ }
+ }
+
+ /*
+ * Exclude offload EM xid range from next EM xid range.
+ */
+ min_xid += lp->lro_xid + 1;
+
+skip_oem:
+ if (!fc_exch_mgr_alloc(lp, FC_CLASS_3, min_xid, max_xid, NULL)) {
+ printk(KERN_ERR "fcoe_em_config: failed to "
+ "allocate em on interface %s\n", fc->real_dev->name);
return -ENOMEM;
+ }
return 0;
}
struct kref kref; /* exchange mgr reference count */
spinlock_t em_lock; /* exchange manager lock,
must be taken before ex_lock */
- u16 last_xid; /* last allocated exchange ID */
+ u16 next_xid; /* next possible free exchange ID */
u16 min_xid; /* min exchange ID */
u16 max_xid; /* max exchange ID */
u16 max_read; /* max exchange ID for read */
return sp;
}
-/*
- * fc_em_alloc_xid - returns an xid based on request type
- * @lp : ptr to associated lport
- * @fp : ptr to the assocated frame
- *
- * check the associated fc_fsp_pkt to get scsi command type and
- * command direction to decide from which range this exch id
- * will be allocated from.
- *
- * Returns : 0 or an valid xid
- */
-static u16 fc_em_alloc_xid(struct fc_exch_mgr *mp, const struct fc_frame *fp)
-{
- u16 xid, min, max;
- u16 *plast;
- struct fc_exch *ep = NULL;
-
- if (mp->max_read) {
- if (fc_fcp_is_read(fr_fsp(fp))) {
- min = mp->min_xid;
- max = mp->max_read;
- plast = &mp->last_read;
- } else {
- min = mp->max_read + 1;
- max = mp->max_xid;
- plast = &mp->last_xid;
- }
- } else {
- min = mp->min_xid;
- max = mp->max_xid;
- plast = &mp->last_xid;
- }
- xid = *plast;
- do {
- xid = (xid == max) ? min : xid + 1;
- ep = mp->exches[xid - mp->min_xid];
- } while ((ep != NULL) && (xid != *plast));
-
- if (unlikely(ep))
- xid = 0;
- else
- *plast = xid;
-
- return xid;
-}
-
/**
* fc_exch_em_alloc() - allocate an exchange from a specified EM.
* @lport: ptr to the local port
* @mp: ptr to the exchange manager
- * @fp: ptr to the FC frame
- * @xid: input xid
*
- * if xid is supplied zero then assign next free exchange ID
- * from exchange manager, otherwise use supplied xid.
- * Returns with exch lock held.
+ * 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_frame *fp, u16 xid)
+ struct fc_exch_mgr *mp)
{
struct fc_exch *ep;
+ u16 min, max, xid;
+
+ min = mp->min_xid;
+ max = mp->max_xid;
/* allocate memory for exchange */
ep = mempool_alloc(mp->ep_pool, GFP_ATOMIC);
memset(ep, 0, sizeof(*ep));
spin_lock_bh(&mp->em_lock);
- /* alloc xid if input xid 0 */
- if (!xid) {
- /* alloc a new xid */
- xid = fc_em_alloc_xid(mp, fp);
- if (!xid) {
- printk(KERN_WARNING "libfc: Failed to allocate an exhange\n");
+ xid = mp->next_xid;
+ /* alloc a new xid */
+ while (mp->exches[xid - min]) {
+ xid = (xid == max) ? min : xid + 1;
+ if (xid == mp->next_xid)
goto err;
- }
}
+ mp->next_xid = (xid == max) ? min : xid + 1;
fc_exch_hold(ep); /* hold for exch in mp */
spin_lock_init(&ep->ex_lock);
list_for_each_entry(ema, &lport->ema_list, ema_list) {
if (!ema->match || ema->match(fp)) {
- ep = fc_exch_em_alloc(lport, ema->mp, fp, 0);
+ ep = fc_exch_em_alloc(lport, ema->mp);
if (ep)
return ep;
}
struct fc_exch_mgr *mp;
size_t len;
- if (max_xid <= min_xid || min_xid == 0 || max_xid == FC_XID_UNKNOWN) {
+ if (max_xid <= min_xid || max_xid == FC_XID_UNKNOWN) {
FC_LPORT_DBG(lp, "Invalid min_xid 0x:%x and max_xid 0x:%x\n",
min_xid, max_xid);
return NULL;
/*
* Memory need for EM
*/
-#define xid_ok(i, m1, m2) (((i) >= (m1)) && ((i) <= (m2)))
len = (max_xid - min_xid + 1) * (sizeof(struct fc_exch *));
len += sizeof(struct fc_exch_mgr);
/* adjust em exch xid range for offload */
mp->min_xid = min_xid;
mp->max_xid = max_xid;
- mp->last_xid = min_xid - 1;
- mp->max_read = 0;
- mp->last_read = 0;
- if (lp->lro_enabled && xid_ok(lp->lro_xid, min_xid, max_xid)) {
- mp->max_read = lp->lro_xid;
- mp->last_read = min_xid - 1;
- mp->last_xid = mp->max_read;
- } else {
- /* disable lro if no xid control over read */
- lp->lro_enabled = 0;
- }
+ mp->next_xid = min_xid;
INIT_LIST_HEAD(&mp->ex_list);
spin_lock_init(&mp->em_lock);
fc_exch_setup_hdr(ep, fp, ep->f_ctl);
sp->cnt++;
- fc_fcp_ddp_setup(fr_fsp(fp), ep->xid);
+ if (ep->xid <= lp->lro_xid)
+ fc_fcp_ddp_setup(fr_fsp(fp), ep->xid);
if (unlikely(lp->tt.frame_send(lp, fp)))
goto err;
projects / users / hch / configfs.git / commitdiff