/* Copyright (c) 2004 Coraid, Inc. See COPYING for GPL terms. */
/*
* aoecmd.c
* Filesystem request handling methods
*/
#include <linux/hdreg.h>
#include <linux/blkdev.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include "aoe.h"
#define TIMERTICK (HZ / 10)
#define MINTIMER (2 * TIMERTICK)
#define MAXTIMER (HZ << 1)
#define MAXWAIT (60 * 3) /* After MAXWAIT seconds, give up and fail dev */
static struct sk_buff *
new_skb(struct net_device *if_dev, ulong len)
{
struct sk_buff *skb;
skb = alloc_skb(len, GFP_ATOMIC);
if (skb) {
skb->nh.raw = skb->mac.raw = skb->data;
skb->dev = if_dev;
skb->protocol = __constant_htons(ETH_P_AOE);
skb->priority = 0;
skb_put(skb, len);
skb->next = skb->prev = NULL;
/* tell the network layer not to perform IP checksums
* or to get the NIC to do it
*/
skb->ip_summed = CHECKSUM_NONE;
}
return skb;
}
static struct sk_buff *
skb_prepare(struct aoedev *d, struct frame *f)
{
struct sk_buff *skb;
char *p;
skb = new_skb(d->ifp, f->ndata + f->writedatalen);
if (!skb) {
printk(KERN_INFO "aoe: skb_prepare: failure to allocate skb\n");
return NULL;
}
p = skb->mac.raw;
memcpy(p, f->data, f->ndata);
if (f->writedatalen) {
p += sizeof(struct aoe_hdr) + sizeof(struct aoe_atahdr);
memcpy(p, f->bufaddr, f->writedatalen);
}
return skb;
}
static struct frame *
getframe(struct aoedev *d, int tag)
{
struct frame *f, *e;
f = d->frames;
e = f + d->nframes;
for (; f<e; f++)
if (f->tag == tag)
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 int
aoehdr_atainit(struct aoedev *d, struct aoe_hdr *h)
{
u16 type = __constant_cpu_to_be16(ETH_P_AOE);
u16 aoemajor = __cpu_to_be16(d->aoemajor);
u32 host_tag = newtag(d);
u32 tag = __cpu_to_be32(host_tag);
memcpy(h->src, d->ifp->dev_addr, sizeof h->src);
memcpy(h->dst, d->addr, sizeof h->dst);
memcpy(h->type, &type, sizeof type);
h->verfl = AOE_HVER;
memcpy(h->major, &aoemajor, sizeof aoemajor);
h->minor = d->aoeminor;
h->cmd = AOECMD_ATA;
memcpy(h->tag, &tag, sizeof tag);
return host_tag;
}
static void
aoecmd_ata_rw(struct aoedev *d, struct frame *f)
{
struct aoe_hdr *h;
struct aoe_atahdr *ah;
struct buf *buf;
struct sk_buff *skb;
ulong bcnt;
register sector_t sector;
char writebit, extbit;
writebit = 0x10;
extbit = 0x4;
buf = d->inprocess;
sector = buf->sector;
bcnt = buf->bv_resid;
if (bcnt > MAXATADATA)
bcnt = MAXATADATA;
/* initialize the headers & frame */
h = (struct aoe_hdr *) f->data;
ah = (struct aoe_atahdr *) (h+1);
f->ndata = sizeof *h + sizeof *ah;
memset(h, 0, f->ndata);
f->tag = aoehdr_atainit(d, h);
f->waited = 0;
f->buf = buf;
f->bufaddr = buf->bufaddr;
/* set up ata header */
ah->scnt = bcnt >> 9;
ah->lba0 = sector;
ah->lba1 = sector >>= 8;
ah->lba2 = sector >>= 8;
ah->lba3 = sector >>= 8;
if (d->flags & DEVFL_EXT) {
ah->aflags |= AOEAFL_EXT;
ah->lba4 = sector >>= 8;
ah->lba5 = sector >>= 8;
} else {
extbit = 0;
ah->lba3 &= 0x0f;
ah->lba3 |= 0xe0; /* LBA bit + obsolete 0xa0 */
}
if (bio_data_dir(buf->bio) == WRITE) {
ah->aflags |= AOEAFL_WRITE;
f->writedatalen = bcnt;
} else {
writebit = 0;
f->writedatalen = 0;
}
ah->cmdstat = WIN_READ | writebit | extbit;
/* mark all tracking fields and load out */
buf->nframesout += 1;
buf->bufaddr += bcnt;
buf->bv_resid -= bcnt;
/* printk(KERN_INFO "aoe: bv_resid=%ld\n", buf->bv_resid); */
buf->resid -= bcnt;
buf->sector += bcnt >> 9;
if (buf->resid == 0) {
d->inprocess = NULL;
} else if (buf->bv_resid == 0) {
buf->bv++;
buf->bv_resid = buf->bv->bv_len;
buf->bufaddr = page_address(buf->bv->bv_page) + buf->bv->bv_offset;
}
skb = skb_prepare(d, f);
if (skb) {
skb->next = d->skblist;
d->skblist = skb;
}
}
/* enters with d->lock held */
void
aoecmd_work(struct aoedev *d)
{
struct frame *f;
struct buf *buf;
loop:
f = getframe(d, FREETAG);
if (f == NULL)
return;
if (d->inprocess == NULL) {
if (list_empty(&d->bufq))
return;
buf = container_of(d->bufq.next, struct buf, bufs);
list_del(d->bufq.next);
/*printk(KERN_INFO "aoecmd_work: bi_size=%ld\n", buf->bio->bi_size); */
d->inprocess = buf;
}
aoecmd_ata_rw(d, f);
goto loop;
}
static void
rexmit(struct aoedev *d, struct frame *f)
{
struct sk_buff *skb;
struct aoe_hdr *h;
char buf[128];
u32 n;
u32 net_tag;
n = newtag(d);
snprintf(buf, sizeof buf,
"%15s e%ld.%ld oldtag=%08x@%08lx newtag=%08x\n",
"retransmit",
d->aoemajor, d->aoeminor, f->tag, jiffies, n);
aoechr_error(buf);
h = (struct aoe_hdr *) f->data;
f->tag = n;
net_tag = __cpu_to_be32(n);
memcpy(h->tag, &net_tag, sizeof net_tag);
skb = skb_prepare(d, f);
if (skb) {
skb->next = d->skblist;
d->skblist = skb;
}
}
static int
tsince(int tag)
{
int n;
n = jiffies & 0xffff;
n -= tag & 0xffff;
if (n < 0)
n += 1<<16;
return n;
}
static void
rexmit_timer(ulong vp)
{
struct aoedev *d;
struct frame *f, *e;
struct sk_buff *sl;
register long timeout;
ulong flags, n;
d = (struct aoedev *) vp;
sl = NULL;
/* timeout is always ~150% of the moving average */
timeout = d->rttavg;
timeout += timeout >> 1;
spin_lock_irqsave(&d->lock, flags);
if (d->flags & DEVFL_TKILL) {
tdie: spin_unlock_irqrestore(&d->lock, flags);
return;
}
f = d->frames;
e = f + d->nframes;
for (; f<e; f++) {
if (f->tag != FREETAG && tsince(f->tag) >= timeout) {
n = f->waited += timeout;
n /= HZ;
if (n > MAXWAIT) { /* waited too long. device failure. */
aoedev_downdev(d);
goto tdie;
}
rexmit(d, f);
}
}
sl = d->skblist;
d->skblist = NULL;
if (sl) {
n = d->rttavg <<= 1;
if (n > MAXTIMER)
d->rttavg = MAXTIMER;
}
d->timer.expires = jiffies + TIMERTICK;
add_timer(&d->timer);
spin_unlock_irqrestore(&d->lock, flags);
aoenet_xmit(sl);
}
static void
ataid_complete(struct aoedev *d, unsigned char *id)
{
u64 ssize;
u16 n;
/* word 83: command set supported */
n = __le16_to_cpu(*((u16 *) &id[83<<1]));
/* word 86: command set/feature enabled */
n |= __le16_to_cpu(*((u16 *) &id[86<<1]));
if (n & (1<<10)) { /* bit 10: LBA 48 */
d->flags |= DEVFL_EXT;
/* word 100: number lba48 sectors */
ssize = __le64_to_cpu(*((u64 *) &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 = __le32_to_cpu(*((u32 *) &id[60<<1]));
/* NOTE: obsolete in ATA 6 */
d->geo.cylinders = __le16_to_cpu(*((u16 *) &id[54<<1]));
d->geo.heads = __le16_to_cpu(*((u16 *) &id[55<<1]));
d->geo.sectors = __le16_to_cpu(*((u16 *) &id[56<<1]));
}
d->ssize = ssize;
d->geo.start = 0;
if (d->gd != NULL) {
d->gd->capacity = ssize;
d->flags |= DEVFL_UP;
return;
}
if (d->flags & DEVFL_WORKON) {
printk(KERN_INFO "aoe: ataid_complete: can't schedule work, it's already on! "
"(This really shouldn't happen).\n");
return;
}
INIT_WORK(&d->work, aoeblk_gdalloc, d);
schedule_work(&d->work);
d->flags |= DEVFL_WORKON;
}
static void
calc_rttavg(struct aoedev *d, int rtt)
{
register long n;
n = rtt;
if (n < MINTIMER)
n = MINTIMER;
else if (n > MAXTIMER)
n = MAXTIMER;
/* g == .25; cf. Congestion Avoidance and Control, Jacobson & Karels; 1988 */
n -= d->rttavg;
d->rttavg += n >> 2;
}
void
aoecmd_ata_rsp(struct sk_buff *skb)
{
struct aoedev *d;
struct aoe_hdr *hin;
struct aoe_atahdr *ahin, *ahout;
struct frame *f;
struct buf *buf;
struct sk_buff *sl;
register long n;
ulong flags;
char ebuf[128];
hin = (struct aoe_hdr *) skb->mac.raw;
d = aoedev_bymac(hin->src);
if (d == NULL) {
snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response "
"for unknown device %d.%d\n",
__be16_to_cpu(*((u16 *) hin->major)),
hin->minor);
aoechr_error(ebuf);
return;
}
spin_lock_irqsave(&d->lock, flags);
f = getframe(d, __be32_to_cpu(*((u32 *) hin->tag)));
if (f == NULL) {
spin_unlock_irqrestore(&d->lock, flags);
snprintf(ebuf, sizeof ebuf,
"%15s e%d.%d tag=%08x@%08lx\n",
"unexpected rsp",
__be16_to_cpu(*((u16 *) hin->major)),
hin->minor,
__be32_to_cpu(*((u32 *) hin->tag)),
jiffies);
aoechr_error(ebuf);
return;
}
calc_rttavg(d, tsince(f->tag));
ahin = (struct aoe_atahdr *) (hin+1);
ahout = (struct aoe_atahdr *) (f->data + sizeof(struct aoe_hdr));
buf = f->buf;
if (ahin->cmdstat & 0xa9) { /* these bits cleared on success */
printk(KERN_CRIT "aoe: aoecmd_ata_rsp: ata error cmd=%2.2Xh "
"stat=%2.2Xh from e%ld.%ld\n",
ahout->cmdstat, ahin->cmdstat,
d->aoemajor, d->aoeminor);
if (buf)
buf->flags |= BUFFL_FAIL;
} else {
switch (ahout->cmdstat) {
case WIN_READ:
case WIN_READ_EXT:
n = ahout->scnt << 9;
if (skb->len - sizeof *hin - sizeof *ahin < n) {
printk(KERN_CRIT "aoe: aoecmd_ata_rsp: runt "
"ata data size in read. skb->len=%d\n",
skb->len);
/* fail frame f? just returning will rexmit. */
spin_unlock_irqrestore(&d->lock, flags);
return;
}
memcpy(f->bufaddr, ahin+1, n);
case WIN_WRITE:
case WIN_WRITE_EXT:
break;
case WIN_IDENTIFY:
if (skb->len - sizeof *hin - sizeof *ahin < 512) {
printk(KERN_INFO "aoe: aoecmd_ata_rsp: runt data size "
"in ataid. skb->len=%d\n", skb->len);
spin_unlock_irqrestore(&d->lock, flags);
return;
}
ataid_complete(d, (char *) (ahin+1));
/* d->flags |= DEVFL_WC_UPDATE; */
break;
default:
printk(KERN_INFO "aoe: aoecmd_ata_rsp: unrecognized "
"outbound ata command %2.2Xh for %d.%d\n",
ahout->cmdstat,
__be16_to_cpu(*((u16 *) hin->major)),
hin->minor);
}
}
if (buf) {
buf->nframesout -= 1;
if (buf->nframesout == 0 && buf->resid == 0) {
n = (buf->flags & BUFFL_FAIL) ? -EIO : 0;
bio_endio(buf->bio, buf->bio->bi_size, n);
mempool_free(buf, d->bufpool);
}
}
f->buf = NULL;
f->tag = FREETAG;
aoecmd_work(d);
sl = d->skblist;
d->skblist = NULL;
spin_unlock_irqrestore(&d->lock, flags);
aoenet_xmit(sl);
}
void
aoecmd_cfg(ushort aoemajor, unsigned char aoeminor)
{
struct aoe_hdr *h;
struct aoe_cfghdr *ch;
struct sk_buff *skb, *sl;
struct net_device *ifp;
u16 aoe_type = __constant_cpu_to_be16(ETH_P_AOE);
u16 net_aoemajor = __cpu_to_be16(aoemajor);
sl = NULL;
read_lock(&dev_base_lock);
for (ifp = dev_base; ifp; dev_put(ifp), ifp = ifp->next) {
dev_hold(ifp);
if (!is_aoe_netif(ifp))
continue;
skb = new_skb(ifp, sizeof *h + sizeof *ch);
if (skb == NULL) {
printk(KERN_INFO "aoe: aoecmd_cfg: skb alloc failure\n");
continue;
}
h = (struct aoe_hdr *) skb->mac.raw;
memset(h, 0, sizeof *h + sizeof *ch);
memset(h->dst, 0xff, sizeof h->dst);
memcpy(h->src, ifp->dev_addr, sizeof h->src);
memcpy(h->type, &aoe_type, sizeof aoe_type);
h->verfl = AOE_HVER;
memcpy(h->major, &net_aoemajor, sizeof net_aoemajor);
h->minor = aoeminor;
h->cmd = AOECMD_CFG;
skb->next = sl;
sl = skb;
}
read_unlock(&dev_base_lock);
aoenet_xmit(sl);
}
/*
* Since we only call this in one place (and it only prepares one frame)
* we just return the skb. Usually we'd chain it up to the d->skblist.
*/
static struct sk_buff *
aoecmd_ata_id(struct aoedev *d)
{
struct aoe_hdr *h;
struct aoe_atahdr *ah;
struct frame *f;
struct sk_buff *skb;
f = getframe(d, FREETAG);
if (f == NULL) {
printk(KERN_CRIT "aoe: aoecmd_ata_id: can't get a frame. "
"This shouldn't happen.\n");
return NULL;
}
/* initialize the headers & frame */
h = (struct aoe_hdr *) f->data;
ah = (struct aoe_atahdr *) (h+1);
f->ndata = sizeof *h + sizeof *ah;
memset(h, 0, f->ndata);
f->tag = aoehdr_atainit(d, h);
f->waited = 0;
f->writedatalen = 0;
/* this message initializes the device, so we reset the rttavg */
d->rttavg = MAXTIMER;
/* set up ata header */
ah->scnt = 1;
ah->cmdstat = WIN_IDENTIFY;
ah->lba3 = 0xa0;
skb = skb_prepare(d, f);
/* we now want to start the rexmit tracking */
d->flags &= ~DEVFL_TKILL;
d->timer.data = (ulong) d;
d->timer.function = rexmit_timer;
d->timer.expires = jiffies + TIMERTICK;
add_timer(&d->timer);
return skb;
}
void
aoecmd_cfg_rsp(struct sk_buff *skb)
{
struct aoedev *d;
struct aoe_hdr *h;
struct aoe_cfghdr *ch;
ulong flags, bufcnt, sysminor, aoemajor;
struct sk_buff *sl;
enum { MAXFRAMES = 8, MAXSYSMINOR = 255 };
h = (struct aoe_hdr *) skb->mac.raw;
ch = (struct aoe_cfghdr *) (h+1);
/*
* Enough people have their dip switches set backwards to
* warrant a loud message for this special case.
*/
aoemajor = __be16_to_cpu(*((u16 *) h->major));
if (aoemajor == 0xfff) {
printk(KERN_CRIT "aoe: aoecmd_cfg_rsp: Warning: shelf "
"address is all ones. Check shelf dip switches\n");
return;
}
sysminor = SYSMINOR(aoemajor, h->minor);
if (sysminor > MAXSYSMINOR) {
printk(KERN_INFO "aoe: aoecmd_cfg_rsp: sysminor %ld too "
"large\n", sysminor);
return;
}
bufcnt = __be16_to_cpu(*((u16 *) ch->bufcnt));
if (bufcnt > MAXFRAMES) /* keep it reasonable */
bufcnt = MAXFRAMES;
d = aoedev_set(sysminor, h->src, skb->dev, bufcnt);
if (d == NULL) {
printk(KERN_INFO "aoe: aoecmd_cfg_rsp: device set failure\n");
return;
}
spin_lock_irqsave(&d->lock, flags);
if (d->flags & (DEVFL_UP | DEVFL_CLOSEWAIT)) {
spin_unlock_irqrestore(&d->lock, flags);
return;
}
d->fw_ver = __be16_to_cpu(*((u16 *) ch->fwver));
/* we get here only if the device is new */
sl = aoecmd_ata_id(d);
spin_unlock_irqrestore(&d->lock, flags);
aoenet_xmit(sl);
}
