From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- drivers/block/aoe/aoecmd.c | 1826 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1826 insertions(+) create mode 100644 drivers/block/aoe/aoecmd.c (limited to 'drivers/block/aoe/aoecmd.c') diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c new file mode 100644 index 000000000..422b7d84f --- /dev/null +++ b/drivers/block/aoe/aoecmd.c @@ -0,0 +1,1826 @@ +/* Copyright (c) 2013 Coraid, Inc. See COPYING for GPL terms. */ +/* + * aoecmd.c + * Filesystem request handling methods + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "aoe.h" + +#define MAXIOC (8192) /* default meant to avoid most soft lockups */ + +static void ktcomplete(struct frame *, struct sk_buff *); +static int count_targets(struct aoedev *d, int *untainted); + +static struct buf *nextbuf(struct aoedev *); + +static int aoe_deadsecs = 60 * 3; +module_param(aoe_deadsecs, int, 0644); +MODULE_PARM_DESC(aoe_deadsecs, "After aoe_deadsecs seconds, give up and fail dev."); + +static int aoe_maxout = 64; +module_param(aoe_maxout, int, 0644); +MODULE_PARM_DESC(aoe_maxout, + "Only aoe_maxout outstanding packets for every MAC on eX.Y."); + +/* The number of online cpus during module initialization gives us a + * convenient heuristic cap on the parallelism used for ktio threads + * doing I/O completion. It is not important that the cap equal the + * actual number of running CPUs at any given time, but because of CPU + * hotplug, we take care to use ncpus instead of using + * num_online_cpus() after module initialization. + */ +static int ncpus; + +/* mutex lock used for synchronization while thread spawning */ +static DEFINE_MUTEX(ktio_spawn_lock); + +static wait_queue_head_t *ktiowq; +static struct ktstate *kts; + +/* io completion queue */ +struct iocq_ktio { + struct list_head head; + spinlock_t lock; +}; +static struct iocq_ktio *iocq; + +static struct page *empty_page; + +static struct sk_buff * +new_skb(ulong len) +{ + struct sk_buff *skb; + + skb = alloc_skb(len + MAX_HEADER, GFP_ATOMIC); + if (skb) { + skb_reserve(skb, MAX_HEADER); + skb_reset_mac_header(skb); + skb_reset_network_header(skb); + skb->protocol = __constant_htons(ETH_P_AOE); + skb_checksum_none_assert(skb); + } + return skb; +} + +static struct frame * +getframe_deferred(struct aoedev *d, u32 tag) +{ + struct list_head *head, *pos, *nx; + struct frame *f; + + head = &d->rexmitq; + list_for_each_safe(pos, nx, head) { + f = list_entry(pos, struct frame, head); + if (f->tag == tag) { + list_del(pos); + return f; + } + } + return NULL; +} + +static struct frame * +getframe(struct aoedev *d, u32 tag) +{ + struct frame *f; + struct list_head *head, *pos, *nx; + u32 n; + + n = tag % NFACTIVE; + head = &d->factive[n]; + list_for_each_safe(pos, nx, head) { + f = list_entry(pos, struct frame, head); + if (f->tag == tag) { + list_del(pos); + return f; + } + } + return NULL; +} + +/* + * Leave the top bit clear so we have tagspace for userland. + * The bottom 16 bits are the xmit tick for rexmit/rttavg processing. + * This driver reserves tag -1 to mean "unused frame." + */ +static int +newtag(struct aoedev *d) +{ + register ulong n; + + n = jiffies & 0xffff; + return n |= (++d->lasttag & 0x7fff) << 16; +} + +static u32 +aoehdr_atainit(struct aoedev *d, struct aoetgt *t, struct aoe_hdr *h) +{ + u32 host_tag = newtag(d); + + memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src); + memcpy(h->dst, t->addr, sizeof h->dst); + h->type = __constant_cpu_to_be16(ETH_P_AOE); + h->verfl = AOE_HVER; + h->major = cpu_to_be16(d->aoemajor); + h->minor = d->aoeminor; + h->cmd = AOECMD_ATA; + h->tag = cpu_to_be32(host_tag); + + return host_tag; +} + +static inline void +put_lba(struct aoe_atahdr *ah, sector_t lba) +{ + ah->lba0 = lba; + ah->lba1 = lba >>= 8; + ah->lba2 = lba >>= 8; + ah->lba3 = lba >>= 8; + ah->lba4 = lba >>= 8; + ah->lba5 = lba >>= 8; +} + +static struct aoeif * +ifrotate(struct aoetgt *t) +{ + struct aoeif *ifp; + + ifp = t->ifp; + ifp++; + if (ifp >= &t->ifs[NAOEIFS] || ifp->nd == NULL) + ifp = t->ifs; + if (ifp->nd == NULL) + return NULL; + return t->ifp = ifp; +} + +static void +skb_pool_put(struct aoedev *d, struct sk_buff *skb) +{ + __skb_queue_tail(&d->skbpool, skb); +} + +static struct sk_buff * +skb_pool_get(struct aoedev *d) +{ + struct sk_buff *skb = skb_peek(&d->skbpool); + + if (skb && atomic_read(&skb_shinfo(skb)->dataref) == 1) { + __skb_unlink(skb, &d->skbpool); + return skb; + } + if (skb_queue_len(&d->skbpool) < NSKBPOOLMAX && + (skb = new_skb(ETH_ZLEN))) + return skb; + + return NULL; +} + +void +aoe_freetframe(struct frame *f) +{ + struct aoetgt *t; + + t = f->t; + f->buf = NULL; + memset(&f->iter, 0, sizeof(f->iter)); + f->r_skb = NULL; + f->flags = 0; + list_add(&f->head, &t->ffree); +} + +static struct frame * +newtframe(struct aoedev *d, struct aoetgt *t) +{ + struct frame *f; + struct sk_buff *skb; + struct list_head *pos; + + if (list_empty(&t->ffree)) { + if (t->falloc >= NSKBPOOLMAX*2) + return NULL; + f = kcalloc(1, sizeof(*f), GFP_ATOMIC); + if (f == NULL) + return NULL; + t->falloc++; + f->t = t; + } else { + pos = t->ffree.next; + list_del(pos); + f = list_entry(pos, struct frame, head); + } + + skb = f->skb; + if (skb == NULL) { + f->skb = skb = new_skb(ETH_ZLEN); + if (!skb) { +bail: aoe_freetframe(f); + return NULL; + } + } + + if (atomic_read(&skb_shinfo(skb)->dataref) != 1) { + skb = skb_pool_get(d); + if (skb == NULL) + goto bail; + skb_pool_put(d, f->skb); + f->skb = skb; + } + + skb->truesize -= skb->data_len; + skb_shinfo(skb)->nr_frags = skb->data_len = 0; + skb_trim(skb, 0); + return f; +} + +static struct frame * +newframe(struct aoedev *d) +{ + struct frame *f; + struct aoetgt *t, **tt; + int totout = 0; + int use_tainted; + int has_untainted; + + if (!d->targets || !d->targets[0]) { + printk(KERN_ERR "aoe: NULL TARGETS!\n"); + return NULL; + } + tt = d->tgt; /* last used target */ + for (use_tainted = 0, has_untainted = 0;;) { + tt++; + if (tt >= &d->targets[d->ntargets] || !*tt) + tt = d->targets; + t = *tt; + if (!t->taint) { + has_untainted = 1; + totout += t->nout; + } + if (t->nout < t->maxout + && (use_tainted || !t->taint) + && t->ifp->nd) { + f = newtframe(d, t); + if (f) { + ifrotate(t); + d->tgt = tt; + return f; + } + } + if (tt == d->tgt) { /* we've looped and found nada */ + if (!use_tainted && !has_untainted) + use_tainted = 1; + else + break; + } + } + if (totout == 0) { + d->kicked++; + d->flags |= DEVFL_KICKME; + } + return NULL; +} + +static void +skb_fillup(struct sk_buff *skb, struct bio *bio, struct bvec_iter iter) +{ + int frag = 0; + struct bio_vec bv; + + __bio_for_each_segment(bv, bio, iter, iter) + skb_fill_page_desc(skb, frag++, bv.bv_page, + bv.bv_offset, bv.bv_len); +} + +static void +fhash(struct frame *f) +{ + struct aoedev *d = f->t->d; + u32 n; + + n = f->tag % NFACTIVE; + list_add_tail(&f->head, &d->factive[n]); +} + +static void +ata_rw_frameinit(struct frame *f) +{ + struct aoetgt *t; + struct aoe_hdr *h; + struct aoe_atahdr *ah; + struct sk_buff *skb; + char writebit, extbit; + + skb = f->skb; + h = (struct aoe_hdr *) skb_mac_header(skb); + ah = (struct aoe_atahdr *) (h + 1); + skb_put(skb, sizeof(*h) + sizeof(*ah)); + memset(h, 0, skb->len); + + writebit = 0x10; + extbit = 0x4; + + t = f->t; + f->tag = aoehdr_atainit(t->d, t, h); + fhash(f); + t->nout++; + f->waited = 0; + f->waited_total = 0; + + /* set up ata header */ + ah->scnt = f->iter.bi_size >> 9; + put_lba(ah, f->iter.bi_sector); + if (t->d->flags & DEVFL_EXT) { + ah->aflags |= AOEAFL_EXT; + } else { + extbit = 0; + ah->lba3 &= 0x0f; + ah->lba3 |= 0xe0; /* LBA bit + obsolete 0xa0 */ + } + if (f->buf && bio_data_dir(f->buf->bio) == WRITE) { + skb_fillup(skb, f->buf->bio, f->iter); + ah->aflags |= AOEAFL_WRITE; + skb->len += f->iter.bi_size; + skb->data_len = f->iter.bi_size; + skb->truesize += f->iter.bi_size; + t->wpkts++; + } else { + t->rpkts++; + writebit = 0; + } + + ah->cmdstat = ATA_CMD_PIO_READ | writebit | extbit; + skb->dev = t->ifp->nd; +} + +static int +aoecmd_ata_rw(struct aoedev *d) +{ + struct frame *f; + struct buf *buf; + struct sk_buff *skb; + struct sk_buff_head queue; + + buf = nextbuf(d); + if (buf == NULL) + return 0; + f = newframe(d); + if (f == NULL) + return 0; + + /* initialize the headers & frame */ + f->buf = buf; + f->iter = buf->iter; + f->iter.bi_size = min_t(unsigned long, + d->maxbcnt ?: DEFAULTBCNT, + f->iter.bi_size); + bio_advance_iter(buf->bio, &buf->iter, f->iter.bi_size); + + if (!buf->iter.bi_size) + d->ip.buf = NULL; + + /* mark all tracking fields and load out */ + buf->nframesout += 1; + + ata_rw_frameinit(f); + + skb = skb_clone(f->skb, GFP_ATOMIC); + if (skb) { + do_gettimeofday(&f->sent); + f->sent_jiffs = (u32) jiffies; + __skb_queue_head_init(&queue); + __skb_queue_tail(&queue, skb); + aoenet_xmit(&queue); + } + return 1; +} + +/* some callers cannot sleep, and they can call this function, + * transmitting the packets later, when interrupts are on + */ +static void +aoecmd_cfg_pkts(ushort aoemajor, unsigned char aoeminor, struct sk_buff_head *queue) +{ + struct aoe_hdr *h; + struct aoe_cfghdr *ch; + struct sk_buff *skb; + struct net_device *ifp; + + rcu_read_lock(); + for_each_netdev_rcu(&init_net, ifp) { + dev_hold(ifp); + if (!is_aoe_netif(ifp)) + goto cont; + + skb = new_skb(sizeof *h + sizeof *ch); + if (skb == NULL) { + printk(KERN_INFO "aoe: skb alloc failure\n"); + goto cont; + } + skb_put(skb, sizeof *h + sizeof *ch); + skb->dev = ifp; + __skb_queue_tail(queue, skb); + h = (struct aoe_hdr *) skb_mac_header(skb); + memset(h, 0, sizeof *h + sizeof *ch); + + memset(h->dst, 0xff, sizeof h->dst); + memcpy(h->src, ifp->dev_addr, sizeof h->src); + h->type = __constant_cpu_to_be16(ETH_P_AOE); + h->verfl = AOE_HVER; + h->major = cpu_to_be16(aoemajor); + h->minor = aoeminor; + h->cmd = AOECMD_CFG; + +cont: + dev_put(ifp); + } + rcu_read_unlock(); +} + +static void +resend(struct aoedev *d, struct frame *f) +{ + struct sk_buff *skb; + struct sk_buff_head queue; + struct aoe_hdr *h; + struct aoetgt *t; + char buf[128]; + u32 n; + + t = f->t; + n = newtag(d); + skb = f->skb; + if (ifrotate(t) == NULL) { + /* probably can't happen, but set it up to fail anyway */ + pr_info("aoe: resend: no interfaces to rotate to.\n"); + ktcomplete(f, NULL); + return; + } + h = (struct aoe_hdr *) skb_mac_header(skb); + + if (!(f->flags & FFL_PROBE)) { + snprintf(buf, sizeof(buf), + "%15s e%ld.%d oldtag=%08x@%08lx newtag=%08x s=%pm d=%pm nout=%d\n", + "retransmit", d->aoemajor, d->aoeminor, + f->tag, jiffies, n, + h->src, h->dst, t->nout); + aoechr_error(buf); + } + + f->tag = n; + fhash(f); + h->tag = cpu_to_be32(n); + memcpy(h->dst, t->addr, sizeof h->dst); + memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src); + + skb->dev = t->ifp->nd; + skb = skb_clone(skb, GFP_ATOMIC); + if (skb == NULL) + return; + do_gettimeofday(&f->sent); + f->sent_jiffs = (u32) jiffies; + __skb_queue_head_init(&queue); + __skb_queue_tail(&queue, skb); + aoenet_xmit(&queue); +} + +static int +tsince_hr(struct frame *f) +{ + struct timeval now; + int n; + + do_gettimeofday(&now); + n = now.tv_usec - f->sent.tv_usec; + n += (now.tv_sec - f->sent.tv_sec) * USEC_PER_SEC; + + if (n < 0) + n = -n; + + /* For relatively long periods, use jiffies to avoid + * discrepancies caused by updates to the system time. + * + * On system with HZ of 1000, 32-bits is over 49 days + * worth of jiffies, or over 71 minutes worth of usecs. + * + * Jiffies overflow is handled by subtraction of unsigned ints: + * (gdb) print (unsigned) 2 - (unsigned) 0xfffffffe + * $3 = 4 + * (gdb) + */ + if (n > USEC_PER_SEC / 4) { + n = ((u32) jiffies) - f->sent_jiffs; + n *= USEC_PER_SEC / HZ; + } + + return n; +} + +static int +tsince(u32 tag) +{ + int n; + + n = jiffies & 0xffff; + n -= tag & 0xffff; + if (n < 0) + n += 1<<16; + return jiffies_to_usecs(n + 1); +} + +static struct aoeif * +getif(struct aoetgt *t, struct net_device *nd) +{ + struct aoeif *p, *e; + + p = t->ifs; + e = p + NAOEIFS; + for (; p < e; p++) + if (p->nd == nd) + return p; + return NULL; +} + +static void +ejectif(struct aoetgt *t, struct aoeif *ifp) +{ + struct aoeif *e; + struct net_device *nd; + ulong n; + + nd = ifp->nd; + e = t->ifs + NAOEIFS - 1; + n = (e - ifp) * sizeof *ifp; + memmove(ifp, ifp+1, n); + e->nd = NULL; + dev_put(nd); +} + +static struct frame * +reassign_frame(struct frame *f) +{ + struct frame *nf; + struct sk_buff *skb; + + nf = newframe(f->t->d); + if (!nf) + return NULL; + if (nf->t == f->t) { + aoe_freetframe(nf); + return NULL; + } + + skb = nf->skb; + nf->skb = f->skb; + nf->buf = f->buf; + nf->iter = f->iter; + nf->waited = 0; + nf->waited_total = f->waited_total; + nf->sent = f->sent; + nf->sent_jiffs = f->sent_jiffs; + f->skb = skb; + + return nf; +} + +static void +probe(struct aoetgt *t) +{ + struct aoedev *d; + struct frame *f; + struct sk_buff *skb; + struct sk_buff_head queue; + size_t n, m; + int frag; + + d = t->d; + f = newtframe(d, t); + if (!f) { + pr_err("%s %pm for e%ld.%d: %s\n", + "aoe: cannot probe remote address", + t->addr, + (long) d->aoemajor, d->aoeminor, + "no frame available"); + return; + } + f->flags |= FFL_PROBE; + ifrotate(t); + f->iter.bi_size = t->d->maxbcnt ? t->d->maxbcnt : DEFAULTBCNT; + ata_rw_frameinit(f); + skb = f->skb; + for (frag = 0, n = f->iter.bi_size; n > 0; ++frag, n -= m) { + if (n < PAGE_SIZE) + m = n; + else + m = PAGE_SIZE; + skb_fill_page_desc(skb, frag, empty_page, 0, m); + } + skb->len += f->iter.bi_size; + skb->data_len = f->iter.bi_size; + skb->truesize += f->iter.bi_size; + + skb = skb_clone(f->skb, GFP_ATOMIC); + if (skb) { + do_gettimeofday(&f->sent); + f->sent_jiffs = (u32) jiffies; + __skb_queue_head_init(&queue); + __skb_queue_tail(&queue, skb); + aoenet_xmit(&queue); + } +} + +static long +rto(struct aoedev *d) +{ + long t; + + t = 2 * d->rttavg >> RTTSCALE; + t += 8 * d->rttdev >> RTTDSCALE; + if (t == 0) + t = 1; + + return t; +} + +static void +rexmit_deferred(struct aoedev *d) +{ + struct aoetgt *t; + struct frame *f; + struct frame *nf; + struct list_head *pos, *nx, *head; + int since; + int untainted; + + count_targets(d, &untainted); + + head = &d->rexmitq; + list_for_each_safe(pos, nx, head) { + f = list_entry(pos, struct frame, head); + t = f->t; + if (t->taint) { + if (!(f->flags & FFL_PROBE)) { + nf = reassign_frame(f); + if (nf) { + if (t->nout_probes == 0 + && untainted > 0) { + probe(t); + t->nout_probes++; + } + list_replace(&f->head, &nf->head); + pos = &nf->head; + aoe_freetframe(f); + f = nf; + t = f->t; + } + } else if (untainted < 1) { + /* don't probe w/o other untainted aoetgts */ + goto stop_probe; + } else if (tsince_hr(f) < t->taint * rto(d)) { + /* reprobe slowly when taint is high */ + continue; + } + } else if (f->flags & FFL_PROBE) { +stop_probe: /* don't probe untainted aoetgts */ + list_del(pos); + aoe_freetframe(f); + /* leaving d->kicked, because this is routine */ + f->t->d->flags |= DEVFL_KICKME; + continue; + } + if (t->nout >= t->maxout) + continue; + list_del(pos); + t->nout++; + if (f->flags & FFL_PROBE) + t->nout_probes++; + since = tsince_hr(f); + f->waited += since; + f->waited_total += since; + resend(d, f); + } +} + +/* An aoetgt accumulates demerits quickly, and successful + * probing redeems the aoetgt slowly. + */ +static void +scorn(struct aoetgt *t) +{ + int n; + + n = t->taint++; + t->taint += t->taint * 2; + if (n > t->taint) + t->taint = n; + if (t->taint > MAX_TAINT) + t->taint = MAX_TAINT; +} + +static int +count_targets(struct aoedev *d, int *untainted) +{ + int i, good; + + for (i = good = 0; i < d->ntargets && d->targets[i]; ++i) + if (d->targets[i]->taint == 0) + good++; + + if (untainted) + *untainted = good; + return i; +} + +static void +rexmit_timer(ulong vp) +{ + struct aoedev *d; + struct aoetgt *t; + struct aoeif *ifp; + struct frame *f; + struct list_head *head, *pos, *nx; + LIST_HEAD(flist); + register long timeout; + ulong flags, n; + int i; + int utgts; /* number of aoetgt descriptors (not slots) */ + int since; + + d = (struct aoedev *) vp; + + spin_lock_irqsave(&d->lock, flags); + + /* timeout based on observed timings and variations */ + timeout = rto(d); + + utgts = count_targets(d, NULL); + + if (d->flags & DEVFL_TKILL) { + spin_unlock_irqrestore(&d->lock, flags); + return; + } + + /* collect all frames to rexmit into flist */ + for (i = 0; i < NFACTIVE; i++) { + head = &d->factive[i]; + list_for_each_safe(pos, nx, head) { + f = list_entry(pos, struct frame, head); + if (tsince_hr(f) < timeout) + break; /* end of expired frames */ + /* move to flist for later processing */ + list_move_tail(pos, &flist); + } + } + + /* process expired frames */ + while (!list_empty(&flist)) { + pos = flist.next; + f = list_entry(pos, struct frame, head); + since = tsince_hr(f); + n = f->waited_total + since; + n /= USEC_PER_SEC; + if (aoe_deadsecs + && n > aoe_deadsecs + && !(f->flags & FFL_PROBE)) { + /* Waited too long. Device failure. + * Hang all frames on first hash bucket for downdev + * to clean up. + */ + list_splice(&flist, &d->factive[0]); + aoedev_downdev(d); + goto out; + } + + t = f->t; + n = f->waited + since; + n /= USEC_PER_SEC; + if (aoe_deadsecs && utgts > 0 + && (n > aoe_deadsecs / utgts || n > HARD_SCORN_SECS)) + scorn(t); /* avoid this target */ + + if (t->maxout != 1) { + t->ssthresh = t->maxout / 2; + t->maxout = 1; + } + + if (f->flags & FFL_PROBE) { + t->nout_probes--; + } else { + ifp = getif(t, f->skb->dev); + if (ifp && ++ifp->lost > (t->nframes << 1) + && (ifp != t->ifs || t->ifs[1].nd)) { + ejectif(t, ifp); + ifp = NULL; + } + } + list_move_tail(pos, &d->rexmitq); + t->nout--; + } + rexmit_deferred(d); + +out: + if ((d->flags & DEVFL_KICKME) && d->blkq) { + d->flags &= ~DEVFL_KICKME; + d->blkq->request_fn(d->blkq); + } + + d->timer.expires = jiffies + TIMERTICK; + add_timer(&d->timer); + + spin_unlock_irqrestore(&d->lock, flags); +} + +static unsigned long +rqbiocnt(struct request *r) +{ + struct bio *bio; + unsigned long n = 0; + + __rq_for_each_bio(bio, r) + n++; + return n; +} + +/* This can be removed if we are certain that no users of the block + * layer will ever use zero-count pages in bios. Otherwise we have to + * protect against the put_page sometimes done by the network layer. + * + * See http://oss.sgi.com/archives/xfs/2007-01/msg00594.html for + * discussion. + * + * We cannot use get_page in the workaround, because it insists on a + * positive page count as a precondition. So we use _count directly. + */ +static void +bio_pageinc(struct bio *bio) +{ + struct bio_vec bv; + struct page *page; + struct bvec_iter iter; + + bio_for_each_segment(bv, bio, iter) { + /* Non-zero page count for non-head members of + * compound pages is no longer allowed by the kernel. + */ + page = compound_head(bv.bv_page); + atomic_inc(&page->_count); + } +} + +static void +bio_pagedec(struct bio *bio) +{ + struct page *page; + struct bio_vec bv; + struct bvec_iter iter; + + bio_for_each_segment(bv, bio, iter) { + page = compound_head(bv.bv_page); + atomic_dec(&page->_count); + } +} + +static void +bufinit(struct buf *buf, struct request *rq, struct bio *bio) +{ + memset(buf, 0, sizeof(*buf)); + buf->rq = rq; + buf->bio = bio; + buf->iter = bio->bi_iter; + bio_pageinc(bio); +} + +static struct buf * +nextbuf(struct aoedev *d) +{ + struct request *rq; + struct request_queue *q; + struct buf *buf; + struct bio *bio; + + q = d->blkq; + if (q == NULL) + return NULL; /* initializing */ + if (d->ip.buf) + return d->ip.buf; + rq = d->ip.rq; + if (rq == NULL) { + rq = blk_peek_request(q); + if (rq == NULL) + return NULL; + blk_start_request(rq); + d->ip.rq = rq; + d->ip.nxbio = rq->bio; + rq->special = (void *) rqbiocnt(rq); + } + buf = mempool_alloc(d->bufpool, GFP_ATOMIC); + if (buf == NULL) { + pr_err("aoe: nextbuf: unable to mempool_alloc!\n"); + return NULL; + } + bio = d->ip.nxbio; + bufinit(buf, rq, bio); + bio = bio->bi_next; + d->ip.nxbio = bio; + if (bio == NULL) + d->ip.rq = NULL; + return d->ip.buf = buf; +} + +/* enters with d->lock held */ +void +aoecmd_work(struct aoedev *d) +{ + rexmit_deferred(d); + while (aoecmd_ata_rw(d)) + ; +} + +/* this function performs work that has been deferred until sleeping is OK + */ +void +aoecmd_sleepwork(struct work_struct *work) +{ + struct aoedev *d = container_of(work, struct aoedev, work); + struct block_device *bd; + u64 ssize; + + if (d->flags & DEVFL_GDALLOC) + aoeblk_gdalloc(d); + + if (d->flags & DEVFL_NEWSIZE) { + ssize = get_capacity(d->gd); + bd = bdget_disk(d->gd, 0); + if (bd) { + mutex_lock(&bd->bd_inode->i_mutex); + i_size_write(bd->bd_inode, (loff_t)ssize<<9); + mutex_unlock(&bd->bd_inode->i_mutex); + bdput(bd); + } + spin_lock_irq(&d->lock); + d->flags |= DEVFL_UP; + d->flags &= ~DEVFL_NEWSIZE; + spin_unlock_irq(&d->lock); + } +} + +static void +ata_ident_fixstring(u16 *id, int ns) +{ + u16 s; + + while (ns-- > 0) { + s = *id; + *id++ = s >> 8 | s << 8; + } +} + +static void +ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id) +{ + u64 ssize; + u16 n; + + /* word 83: command set supported */ + n = get_unaligned_le16(&id[83 << 1]); + + /* word 86: command set/feature enabled */ + n |= get_unaligned_le16(&id[86 << 1]); + + if (n & (1<<10)) { /* bit 10: LBA 48 */ + d->flags |= DEVFL_EXT; + + /* word 100: number lba48 sectors */ + ssize = get_unaligned_le64(&id[100 << 1]); + + /* set as in ide-disk.c:init_idedisk_capacity */ + d->geo.cylinders = ssize; + d->geo.cylinders /= (255 * 63); + d->geo.heads = 255; + d->geo.sectors = 63; + } else { + d->flags &= ~DEVFL_EXT; + + /* number lba28 sectors */ + ssize = get_unaligned_le32(&id[60 << 1]); + + /* NOTE: obsolete in ATA 6 */ + d->geo.cylinders = get_unaligned_le16(&id[54 << 1]); + d->geo.heads = get_unaligned_le16(&id[55 << 1]); + d->geo.sectors = get_unaligned_le16(&id[56 << 1]); + } + + ata_ident_fixstring((u16 *) &id[10<<1], 10); /* serial */ + ata_ident_fixstring((u16 *) &id[23<<1], 4); /* firmware */ + ata_ident_fixstring((u16 *) &id[27<<1], 20); /* model */ + memcpy(d->ident, id, sizeof(d->ident)); + + if (d->ssize != ssize) + printk(KERN_INFO + "aoe: %pm e%ld.%d v%04x has %llu sectors\n", + t->addr, + d->aoemajor, d->aoeminor, + d->fw_ver, (long long)ssize); + d->ssize = ssize; + d->geo.start = 0; + if (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE)) + return; + if (d->gd != NULL) { + set_capacity(d->gd, ssize); + d->flags |= DEVFL_NEWSIZE; + } else + d->flags |= DEVFL_GDALLOC; + schedule_work(&d->work); +} + +static void +calc_rttavg(struct aoedev *d, struct aoetgt *t, int rtt) +{ + register long n; + + n = rtt; + + /* cf. Congestion Avoidance and Control, Jacobson & Karels, 1988 */ + n -= d->rttavg >> RTTSCALE; + d->rttavg += n; + if (n < 0) + n = -n; + n -= d->rttdev >> RTTDSCALE; + d->rttdev += n; + + if (!t || t->maxout >= t->nframes) + return; + if (t->maxout < t->ssthresh) + t->maxout += 1; + else if (t->nout == t->maxout && t->next_cwnd-- == 0) { + t->maxout += 1; + t->next_cwnd = t->maxout; + } +} + +static struct aoetgt * +gettgt(struct aoedev *d, char *addr) +{ + struct aoetgt **t, **e; + + t = d->targets; + e = t + d->ntargets; + for (; t < e && *t; t++) + if (memcmp((*t)->addr, addr, sizeof((*t)->addr)) == 0) + return *t; + return NULL; +} + +static void +bvcpy(struct sk_buff *skb, struct bio *bio, struct bvec_iter iter, long cnt) +{ + int soff = 0; + struct bio_vec bv; + + iter.bi_size = cnt; + + __bio_for_each_segment(bv, bio, iter, iter) { + char *p = page_address(bv.bv_page) + bv.bv_offset; + skb_copy_bits(skb, soff, p, bv.bv_len); + soff += bv.bv_len; + } +} + +void +aoe_end_request(struct aoedev *d, struct request *rq, int fastfail) +{ + struct bio *bio; + int bok; + struct request_queue *q; + + q = d->blkq; + if (rq == d->ip.rq) + d->ip.rq = NULL; + do { + bio = rq->bio; + bok = !fastfail && test_bit(BIO_UPTODATE, &bio->bi_flags); + } while (__blk_end_request(rq, bok ? 0 : -EIO, bio->bi_iter.bi_size)); + + /* cf. http://lkml.org/lkml/2006/10/31/28 */ + if (!fastfail) + __blk_run_queue(q); +} + +static void +aoe_end_buf(struct aoedev *d, struct buf *buf) +{ + struct request *rq; + unsigned long n; + + if (buf == d->ip.buf) + d->ip.buf = NULL; + rq = buf->rq; + bio_pagedec(buf->bio); + mempool_free(buf, d->bufpool); + n = (unsigned long) rq->special; + rq->special = (void *) --n; + if (n == 0) + aoe_end_request(d, rq, 0); +} + +static void +ktiocomplete(struct frame *f) +{ + struct aoe_hdr *hin, *hout; + struct aoe_atahdr *ahin, *ahout; + struct buf *buf; + struct sk_buff *skb; + struct aoetgt *t; + struct aoeif *ifp; + struct aoedev *d; + long n; + int untainted; + + if (f == NULL) + return; + + t = f->t; + d = t->d; + skb = f->r_skb; + buf = f->buf; + if (f->flags & FFL_PROBE) + goto out; + if (!skb) /* just fail the buf. */ + goto noskb; + + hout = (struct aoe_hdr *) skb_mac_header(f->skb); + ahout = (struct aoe_atahdr *) (hout+1); + + hin = (struct aoe_hdr *) skb->data; + skb_pull(skb, sizeof(*hin)); + ahin = (struct aoe_atahdr *) skb->data; + skb_pull(skb, sizeof(*ahin)); + if (ahin->cmdstat & 0xa9) { /* these bits cleared on success */ + pr_err("aoe: ata error cmd=%2.2Xh stat=%2.2Xh from e%ld.%d\n", + ahout->cmdstat, ahin->cmdstat, + d->aoemajor, d->aoeminor); +noskb: if (buf) + clear_bit(BIO_UPTODATE, &buf->bio->bi_flags); + goto out; + } + + n = ahout->scnt << 9; + switch (ahout->cmdstat) { + case ATA_CMD_PIO_READ: + case ATA_CMD_PIO_READ_EXT: + if (skb->len < n) { + pr_err("%s e%ld.%d. skb->len=%d need=%ld\n", + "aoe: runt data size in read from", + (long) d->aoemajor, d->aoeminor, + skb->len, n); + clear_bit(BIO_UPTODATE, &buf->bio->bi_flags); + break; + } + if (n > f->iter.bi_size) { + pr_err_ratelimited("%s e%ld.%d. bytes=%ld need=%u\n", + "aoe: too-large data size in read from", + (long) d->aoemajor, d->aoeminor, + n, f->iter.bi_size); + clear_bit(BIO_UPTODATE, &buf->bio->bi_flags); + break; + } + bvcpy(skb, f->buf->bio, f->iter, n); + case ATA_CMD_PIO_WRITE: + case ATA_CMD_PIO_WRITE_EXT: + spin_lock_irq(&d->lock); + ifp = getif(t, skb->dev); + if (ifp) + ifp->lost = 0; + spin_unlock_irq(&d->lock); + break; + case ATA_CMD_ID_ATA: + if (skb->len < 512) { + pr_info("%s e%ld.%d. skb->len=%d need=512\n", + "aoe: runt data size in ataid from", + (long) d->aoemajor, d->aoeminor, + skb->len); + break; + } + if (skb_linearize(skb)) + break; + spin_lock_irq(&d->lock); + ataid_complete(d, t, skb->data); + spin_unlock_irq(&d->lock); + break; + default: + pr_info("aoe: unrecognized ata command %2.2Xh for %d.%d\n", + ahout->cmdstat, + be16_to_cpu(get_unaligned(&hin->major)), + hin->minor); + } +out: + spin_lock_irq(&d->lock); + if (t->taint > 0 + && --t->taint > 0 + && t->nout_probes == 0) { + count_targets(d, &untainted); + if (untainted > 0) { + probe(t); + t->nout_probes++; + } + } + + aoe_freetframe(f); + + if (buf && --buf->nframesout == 0 && buf->iter.bi_size == 0) + aoe_end_buf(d, buf); + + spin_unlock_irq(&d->lock); + aoedev_put(d); + dev_kfree_skb(skb); +} + +/* Enters with iocq.lock held. + * Returns true iff responses needing processing remain. + */ +static int +ktio(int id) +{ + struct frame *f; + struct list_head *pos; + int i; + int actual_id; + + for (i = 0; ; ++i) { + if (i == MAXIOC) + return 1; + if (list_empty(&iocq[id].head)) + return 0; + pos = iocq[id].head.next; + list_del(pos); + f = list_entry(pos, struct frame, head); + spin_unlock_irq(&iocq[id].lock); + ktiocomplete(f); + + /* Figure out if extra threads are required. */ + actual_id = f->t->d->aoeminor % ncpus; + + if (!kts[actual_id].active) { + BUG_ON(id != 0); + mutex_lock(&ktio_spawn_lock); + if (!kts[actual_id].active + && aoe_ktstart(&kts[actual_id]) == 0) + kts[actual_id].active = 1; + mutex_unlock(&ktio_spawn_lock); + } + spin_lock_irq(&iocq[id].lock); + } +} + +static int +kthread(void *vp) +{ + struct ktstate *k; + DECLARE_WAITQUEUE(wait, current); + int more; + + k = vp; + current->flags |= PF_NOFREEZE; + set_user_nice(current, -10); + complete(&k->rendez); /* tell spawner we're running */ + do { + spin_lock_irq(k->lock); + more = k->fn(k->id); + if (!more) { + add_wait_queue(k->waitq, &wait); + __set_current_state(TASK_INTERRUPTIBLE); + } + spin_unlock_irq(k->lock); + if (!more) { + schedule(); + remove_wait_queue(k->waitq, &wait); + } else + cond_resched(); + } while (!kthread_should_stop()); + complete(&k->rendez); /* tell spawner we're stopping */ + return 0; +} + +void +aoe_ktstop(struct ktstate *k) +{ + kthread_stop(k->task); + wait_for_completion(&k->rendez); +} + +int +aoe_ktstart(struct ktstate *k) +{ + struct task_struct *task; + + init_completion(&k->rendez); + task = kthread_run(kthread, k, "%s", k->name); + if (task == NULL || IS_ERR(task)) + return -ENOMEM; + k->task = task; + wait_for_completion(&k->rendez); /* allow kthread to start */ + init_completion(&k->rendez); /* for waiting for exit later */ + return 0; +} + +/* pass it off to kthreads for processing */ +static void +ktcomplete(struct frame *f, struct sk_buff *skb) +{ + int id; + ulong flags; + + f->r_skb = skb; + id = f->t->d->aoeminor % ncpus; + spin_lock_irqsave(&iocq[id].lock, flags); + if (!kts[id].active) { + spin_unlock_irqrestore(&iocq[id].lock, flags); + /* The thread with id has not been spawned yet, + * so delegate the work to the main thread and + * try spawning a new thread. + */ + id = 0; + spin_lock_irqsave(&iocq[id].lock, flags); + } + list_add_tail(&f->head, &iocq[id].head); + spin_unlock_irqrestore(&iocq[id].lock, flags); + wake_up(&ktiowq[id]); +} + +struct sk_buff * +aoecmd_ata_rsp(struct sk_buff *skb) +{ + struct aoedev *d; + struct aoe_hdr *h; + struct frame *f; + u32 n; + ulong flags; + char ebuf[128]; + u16 aoemajor; + + h = (struct aoe_hdr *) skb->data; + aoemajor = be16_to_cpu(get_unaligned(&h->major)); + d = aoedev_by_aoeaddr(aoemajor, h->minor, 0); + if (d == NULL) { + snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response " + "for unknown device %d.%d\n", + aoemajor, h->minor); + aoechr_error(ebuf); + return skb; + } + + spin_lock_irqsave(&d->lock, flags); + + n = be32_to_cpu(get_unaligned(&h->tag)); + f = getframe(d, n); + if (f) { + calc_rttavg(d, f->t, tsince_hr(f)); + f->t->nout--; + if (f->flags & FFL_PROBE) + f->t->nout_probes--; + } else { + f = getframe_deferred(d, n); + if (f) { + calc_rttavg(d, NULL, tsince_hr(f)); + } else { + calc_rttavg(d, NULL, tsince(n)); + spin_unlock_irqrestore(&d->lock, flags); + aoedev_put(d); + snprintf(ebuf, sizeof(ebuf), + "%15s e%d.%d tag=%08x@%08lx s=%pm d=%pm\n", + "unexpected rsp", + get_unaligned_be16(&h->major), + h->minor, + get_unaligned_be32(&h->tag), + jiffies, + h->src, + h->dst); + aoechr_error(ebuf); + return skb; + } + } + aoecmd_work(d); + + spin_unlock_irqrestore(&d->lock, flags); + + ktcomplete(f, skb); + + /* + * Note here that we do not perform an aoedev_put, as we are + * leaving this reference for the ktio to release. + */ + return NULL; +} + +void +aoecmd_cfg(ushort aoemajor, unsigned char aoeminor) +{ + struct sk_buff_head queue; + + __skb_queue_head_init(&queue); + aoecmd_cfg_pkts(aoemajor, aoeminor, &queue); + aoenet_xmit(&queue); +} + +struct sk_buff * +aoecmd_ata_id(struct aoedev *d) +{ + struct aoe_hdr *h; + struct aoe_atahdr *ah; + struct frame *f; + struct sk_buff *skb; + struct aoetgt *t; + + f = newframe(d); + if (f == NULL) + return NULL; + + t = *d->tgt; + + /* initialize the headers & frame */ + skb = f->skb; + h = (struct aoe_hdr *) skb_mac_header(skb); + ah = (struct aoe_atahdr *) (h+1); + skb_put(skb, sizeof *h + sizeof *ah); + memset(h, 0, skb->len); + f->tag = aoehdr_atainit(d, t, h); + fhash(f); + t->nout++; + f->waited = 0; + f->waited_total = 0; + + /* set up ata header */ + ah->scnt = 1; + ah->cmdstat = ATA_CMD_ID_ATA; + ah->lba3 = 0xa0; + + skb->dev = t->ifp->nd; + + d->rttavg = RTTAVG_INIT; + d->rttdev = RTTDEV_INIT; + d->timer.function = rexmit_timer; + + skb = skb_clone(skb, GFP_ATOMIC); + if (skb) { + do_gettimeofday(&f->sent); + f->sent_jiffs = (u32) jiffies; + } + + return skb; +} + +static struct aoetgt ** +grow_targets(struct aoedev *d) +{ + ulong oldn, newn; + struct aoetgt **tt; + + oldn = d->ntargets; + newn = oldn * 2; + tt = kcalloc(newn, sizeof(*d->targets), GFP_ATOMIC); + if (!tt) + return NULL; + memmove(tt, d->targets, sizeof(*d->targets) * oldn); + d->tgt = tt + (d->tgt - d->targets); + kfree(d->targets); + d->targets = tt; + d->ntargets = newn; + + return &d->targets[oldn]; +} + +static struct aoetgt * +addtgt(struct aoedev *d, char *addr, ulong nframes) +{ + struct aoetgt *t, **tt, **te; + + tt = d->targets; + te = tt + d->ntargets; + for (; tt < te && *tt; tt++) + ; + + if (tt == te) { + tt = grow_targets(d); + if (!tt) + goto nomem; + } + t = kzalloc(sizeof(*t), GFP_ATOMIC); + if (!t) + goto nomem; + t->nframes = nframes; + t->d = d; + memcpy(t->addr, addr, sizeof t->addr); + t->ifp = t->ifs; + aoecmd_wreset(t); + t->maxout = t->nframes / 2; + INIT_LIST_HEAD(&t->ffree); + return *tt = t; + + nomem: + pr_info("aoe: cannot allocate memory to add target\n"); + return NULL; +} + +static void +setdbcnt(struct aoedev *d) +{ + struct aoetgt **t, **e; + int bcnt = 0; + + t = d->targets; + e = t + d->ntargets; + for (; t < e && *t; t++) + if (bcnt == 0 || bcnt > (*t)->minbcnt) + bcnt = (*t)->minbcnt; + if (bcnt != d->maxbcnt) { + d->maxbcnt = bcnt; + pr_info("aoe: e%ld.%d: setting %d byte data frames\n", + d->aoemajor, d->aoeminor, bcnt); + } +} + +static void +setifbcnt(struct aoetgt *t, struct net_device *nd, int bcnt) +{ + struct aoedev *d; + struct aoeif *p, *e; + int minbcnt; + + d = t->d; + minbcnt = bcnt; + p = t->ifs; + e = p + NAOEIFS; + for (; p < e; p++) { + if (p->nd == NULL) + break; /* end of the valid interfaces */ + if (p->nd == nd) { + p->bcnt = bcnt; /* we're updating */ + nd = NULL; + } else if (minbcnt > p->bcnt) + minbcnt = p->bcnt; /* find the min interface */ + } + if (nd) { + if (p == e) { + pr_err("aoe: device setifbcnt failure; too many interfaces.\n"); + return; + } + dev_hold(nd); + p->nd = nd; + p->bcnt = bcnt; + } + t->minbcnt = minbcnt; + setdbcnt(d); +} + +void +aoecmd_cfg_rsp(struct sk_buff *skb) +{ + struct aoedev *d; + struct aoe_hdr *h; + struct aoe_cfghdr *ch; + struct aoetgt *t; + ulong flags, aoemajor; + struct sk_buff *sl; + struct sk_buff_head queue; + u16 n; + + sl = NULL; + h = (struct aoe_hdr *) skb_mac_header(skb); + ch = (struct aoe_cfghdr *) (h+1); + + /* + * Enough people have their dip switches set backwards to + * warrant a loud message for this special case. + */ + aoemajor = get_unaligned_be16(&h->major); + if (aoemajor == 0xfff) { + printk(KERN_ERR "aoe: Warning: shelf address is all ones. " + "Check shelf dip switches.\n"); + return; + } + if (aoemajor == 0xffff) { + pr_info("aoe: e%ld.%d: broadcast shelf number invalid\n", + aoemajor, (int) h->minor); + return; + } + if (h->minor == 0xff) { + pr_info("aoe: e%ld.%d: broadcast slot number invalid\n", + aoemajor, (int) h->minor); + return; + } + + n = be16_to_cpu(ch->bufcnt); + if (n > aoe_maxout) /* keep it reasonable */ + n = aoe_maxout; + + d = aoedev_by_aoeaddr(aoemajor, h->minor, 1); + if (d == NULL) { + pr_info("aoe: device allocation failure\n"); + return; + } + + spin_lock_irqsave(&d->lock, flags); + + t = gettgt(d, h->src); + if (t) { + t->nframes = n; + if (n < t->maxout) + aoecmd_wreset(t); + } else { + t = addtgt(d, h->src, n); + if (!t) + goto bail; + } + n = skb->dev->mtu; + n -= sizeof(struct aoe_hdr) + sizeof(struct aoe_atahdr); + n /= 512; + if (n > ch->scnt) + n = ch->scnt; + n = n ? n * 512 : DEFAULTBCNT; + setifbcnt(t, skb->dev, n); + + /* don't change users' perspective */ + if (d->nopen == 0) { + d->fw_ver = be16_to_cpu(ch->fwver); + sl = aoecmd_ata_id(d); + } +bail: + spin_unlock_irqrestore(&d->lock, flags); + aoedev_put(d); + if (sl) { + __skb_queue_head_init(&queue); + __skb_queue_tail(&queue, sl); + aoenet_xmit(&queue); + } +} + +void +aoecmd_wreset(struct aoetgt *t) +{ + t->maxout = 1; + t->ssthresh = t->nframes / 2; + t->next_cwnd = t->nframes; +} + +void +aoecmd_cleanslate(struct aoedev *d) +{ + struct aoetgt **t, **te; + + d->rttavg = RTTAVG_INIT; + d->rttdev = RTTDEV_INIT; + d->maxbcnt = 0; + + t = d->targets; + te = t + d->ntargets; + for (; t < te && *t; t++) + aoecmd_wreset(*t); +} + +void +aoe_failbuf(struct aoedev *d, struct buf *buf) +{ + if (buf == NULL) + return; + buf->iter.bi_size = 0; + clear_bit(BIO_UPTODATE, &buf->bio->bi_flags); + if (buf->nframesout == 0) + aoe_end_buf(d, buf); +} + +void +aoe_flush_iocq(void) +{ + int i; + + for (i = 0; i < ncpus; i++) { + if (kts[i].active) + aoe_flush_iocq_by_index(i); + } +} + +void +aoe_flush_iocq_by_index(int id) +{ + struct frame *f; + struct aoedev *d; + LIST_HEAD(flist); + struct list_head *pos; + struct sk_buff *skb; + ulong flags; + + spin_lock_irqsave(&iocq[id].lock, flags); + list_splice_init(&iocq[id].head, &flist); + spin_unlock_irqrestore(&iocq[id].lock, flags); + while (!list_empty(&flist)) { + pos = flist.next; + list_del(pos); + f = list_entry(pos, struct frame, head); + d = f->t->d; + skb = f->r_skb; + spin_lock_irqsave(&d->lock, flags); + if (f->buf) { + f->buf->nframesout--; + aoe_failbuf(d, f->buf); + } + aoe_freetframe(f); + spin_unlock_irqrestore(&d->lock, flags); + dev_kfree_skb(skb); + aoedev_put(d); + } +} + +int __init +aoecmd_init(void) +{ + void *p; + int i; + int ret; + + /* get_zeroed_page returns page with ref count 1 */ + p = (void *) get_zeroed_page(GFP_KERNEL | __GFP_REPEAT); + if (!p) + return -ENOMEM; + empty_page = virt_to_page(p); + + ncpus = num_online_cpus(); + + iocq = kcalloc(ncpus, sizeof(struct iocq_ktio), GFP_KERNEL); + if (!iocq) + return -ENOMEM; + + kts = kcalloc(ncpus, sizeof(struct ktstate), GFP_KERNEL); + if (!kts) { + ret = -ENOMEM; + goto kts_fail; + } + + ktiowq = kcalloc(ncpus, sizeof(wait_queue_head_t), GFP_KERNEL); + if (!ktiowq) { + ret = -ENOMEM; + goto ktiowq_fail; + } + + mutex_init(&ktio_spawn_lock); + + for (i = 0; i < ncpus; i++) { + INIT_LIST_HEAD(&iocq[i].head); + spin_lock_init(&iocq[i].lock); + init_waitqueue_head(&ktiowq[i]); + snprintf(kts[i].name, sizeof(kts[i].name), "aoe_ktio%d", i); + kts[i].fn = ktio; + kts[i].waitq = &ktiowq[i]; + kts[i].lock = &iocq[i].lock; + kts[i].id = i; + kts[i].active = 0; + } + kts[0].active = 1; + if (aoe_ktstart(&kts[0])) { + ret = -ENOMEM; + goto ktstart_fail; + } + return 0; + +ktstart_fail: + kfree(ktiowq); +ktiowq_fail: + kfree(kts); +kts_fail: + kfree(iocq); + + return ret; +} + +void +aoecmd_exit(void) +{ + int i; + + for (i = 0; i < ncpus; i++) + if (kts[i].active) + aoe_ktstop(&kts[i]); + + aoe_flush_iocq(); + + /* Free up the iocq and thread speicific configuration + * allocated during startup. + */ + kfree(iocq); + kfree(kts); + kfree(ktiowq); + + free_page((unsigned long) page_address(empty_page)); + empty_page = NULL; +} -- cgit v1.2.3-54-g00ecf