linux/drivers/block/sunvdc.c
Dwight Engen d0aedcd4f1 vio: fix reuse of vio_dring slot
vio_dring_avail() will allow use of every dring entry, but when the last
entry is allocated then dr->prod == dr->cons which is indistinguishable from
the ring empty condition. This causes the next allocation to reuse an entry.
When this happens in sunvdc, the server side vds driver begins nack'ing the
messages and ends up resetting the ldc channel. This problem does not effect
sunvnet since it checks for < 2.

The fix here is to just never allocate the very last dring slot so that full
and empty are not the same condition. The request start path was changed to
check for the ring being full a bit earlier, and to stop the blk_queue if
there is no space left. The blk_queue will be restarted once the ring is
only half full again. The number of ring entries was increased to 512 which
matches the sunvnet and Solaris vdc drivers, and greatly reduces the
frequency of hitting the ring full condition and the associated blk_queue
stop/starting. The checks in sunvent were adjusted to account for
vio_dring_avail() returning 1 less.

Orabug: 19441666
OraBZ: 14983

Signed-off-by: Dwight Engen <dwight.engen@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30 14:37:35 -07:00

967 lines
22 KiB
C

/* sunvdc.c: Sun LDOM Virtual Disk Client.
*
* Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/blkdev.h>
#include <linux/hdreg.h>
#include <linux/genhd.h>
#include <linux/cdrom.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/scatterlist.h>
#include <asm/vio.h>
#include <asm/ldc.h>
#define DRV_MODULE_NAME "sunvdc"
#define PFX DRV_MODULE_NAME ": "
#define DRV_MODULE_VERSION "1.1"
#define DRV_MODULE_RELDATE "February 13, 2013"
static char version[] =
DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
MODULE_DESCRIPTION("Sun LDOM virtual disk client driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_MODULE_VERSION);
#define VDC_TX_RING_SIZE 512
#define WAITING_FOR_LINK_UP 0x01
#define WAITING_FOR_TX_SPACE 0x02
#define WAITING_FOR_GEN_CMD 0x04
#define WAITING_FOR_ANY -1
struct vdc_req_entry {
struct request *req;
};
struct vdc_port {
struct vio_driver_state vio;
struct gendisk *disk;
struct vdc_completion *cmp;
u64 req_id;
u64 seq;
struct vdc_req_entry rq_arr[VDC_TX_RING_SIZE];
unsigned long ring_cookies;
u64 max_xfer_size;
u32 vdisk_block_size;
/* The server fills these in for us in the disk attribute
* ACK packet.
*/
u64 operations;
u32 vdisk_size;
u8 vdisk_type;
u8 vdisk_mtype;
char disk_name[32];
struct vio_disk_vtoc label;
};
static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
{
return container_of(vio, struct vdc_port, vio);
}
/* Ordered from largest major to lowest */
static struct vio_version vdc_versions[] = {
{ .major = 1, .minor = 1 },
{ .major = 1, .minor = 0 },
};
static inline int vdc_version_supported(struct vdc_port *port,
u16 major, u16 minor)
{
return port->vio.ver.major == major && port->vio.ver.minor >= minor;
}
#define VDCBLK_NAME "vdisk"
static int vdc_major;
#define PARTITION_SHIFT 3
static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr)
{
return vio_dring_avail(dr, VDC_TX_RING_SIZE);
}
static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
struct gendisk *disk = bdev->bd_disk;
sector_t nsect = get_capacity(disk);
sector_t cylinders = nsect;
geo->heads = 0xff;
geo->sectors = 0x3f;
sector_div(cylinders, geo->heads * geo->sectors);
geo->cylinders = cylinders;
if ((sector_t)(geo->cylinders + 1) * geo->heads * geo->sectors < nsect)
geo->cylinders = 0xffff;
return 0;
}
/* Add ioctl/CDROM_GET_CAPABILITY to support cdrom_id in udev
* when vdisk_mtype is VD_MEDIA_TYPE_CD or VD_MEDIA_TYPE_DVD.
* Needed to be able to install inside an ldom from an iso image.
*/
static int vdc_ioctl(struct block_device *bdev, fmode_t mode,
unsigned command, unsigned long argument)
{
int i;
struct gendisk *disk;
switch (command) {
case CDROMMULTISESSION:
pr_debug(PFX "Multisession CDs not supported\n");
for (i = 0; i < sizeof(struct cdrom_multisession); i++)
if (put_user(0, (char __user *)(argument + i)))
return -EFAULT;
return 0;
case CDROM_GET_CAPABILITY:
disk = bdev->bd_disk;
if (bdev->bd_disk && (disk->flags & GENHD_FL_CD))
return 0;
return -EINVAL;
default:
pr_debug(PFX "ioctl %08x not supported\n", command);
return -EINVAL;
}
}
static const struct block_device_operations vdc_fops = {
.owner = THIS_MODULE,
.getgeo = vdc_getgeo,
.ioctl = vdc_ioctl,
};
static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)
{
if (vio->cmp &&
(waiting_for == -1 ||
vio->cmp->waiting_for == waiting_for)) {
vio->cmp->err = err;
complete(&vio->cmp->com);
vio->cmp = NULL;
}
}
static void vdc_handshake_complete(struct vio_driver_state *vio)
{
vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
}
static int vdc_handle_unknown(struct vdc_port *port, void *arg)
{
struct vio_msg_tag *pkt = arg;
printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n",
pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
printk(KERN_ERR PFX "Resetting connection.\n");
ldc_disconnect(port->vio.lp);
return -ECONNRESET;
}
static int vdc_send_attr(struct vio_driver_state *vio)
{
struct vdc_port *port = to_vdc_port(vio);
struct vio_disk_attr_info pkt;
memset(&pkt, 0, sizeof(pkt));
pkt.tag.type = VIO_TYPE_CTRL;
pkt.tag.stype = VIO_SUBTYPE_INFO;
pkt.tag.stype_env = VIO_ATTR_INFO;
pkt.tag.sid = vio_send_sid(vio);
pkt.xfer_mode = VIO_DRING_MODE;
pkt.vdisk_block_size = port->vdisk_block_size;
pkt.max_xfer_size = port->max_xfer_size;
viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size);
return vio_ldc_send(&port->vio, &pkt, sizeof(pkt));
}
static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
{
struct vdc_port *port = to_vdc_port(vio);
struct vio_disk_attr_info *pkt = arg;
viodbg(HS, "GOT ATTR stype[0x%x] ops[%llx] disk_size[%llu] disk_type[%x] "
"mtype[0x%x] xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
pkt->tag.stype, pkt->operations,
pkt->vdisk_size, pkt->vdisk_type, pkt->vdisk_mtype,
pkt->xfer_mode, pkt->vdisk_block_size,
pkt->max_xfer_size);
if (pkt->tag.stype == VIO_SUBTYPE_ACK) {
switch (pkt->vdisk_type) {
case VD_DISK_TYPE_DISK:
case VD_DISK_TYPE_SLICE:
break;
default:
printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n",
vio->name, pkt->vdisk_type);
return -ECONNRESET;
}
if (pkt->vdisk_block_size > port->vdisk_block_size) {
printk(KERN_ERR PFX "%s: BLOCK size increased "
"%u --> %u\n",
vio->name,
port->vdisk_block_size, pkt->vdisk_block_size);
return -ECONNRESET;
}
port->operations = pkt->operations;
port->vdisk_type = pkt->vdisk_type;
if (vdc_version_supported(port, 1, 1)) {
port->vdisk_size = pkt->vdisk_size;
port->vdisk_mtype = pkt->vdisk_mtype;
}
if (pkt->max_xfer_size < port->max_xfer_size)
port->max_xfer_size = pkt->max_xfer_size;
port->vdisk_block_size = pkt->vdisk_block_size;
return 0;
} else {
printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name);
return -ECONNRESET;
}
}
static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc)
{
int err = desc->status;
vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD);
}
static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
unsigned int index)
{
struct vio_disk_desc *desc = vio_dring_entry(dr, index);
struct vdc_req_entry *rqe = &port->rq_arr[index];
struct request *req;
if (unlikely(desc->hdr.state != VIO_DESC_DONE))
return;
ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
desc->hdr.state = VIO_DESC_FREE;
dr->cons = (index + 1) & (VDC_TX_RING_SIZE - 1);
req = rqe->req;
if (req == NULL) {
vdc_end_special(port, desc);
return;
}
rqe->req = NULL;
__blk_end_request(req, (desc->status ? -EIO : 0), desc->size);
/* restart blk queue when ring is half emptied */
if (blk_queue_stopped(port->disk->queue) &&
vdc_tx_dring_avail(dr) * 100 / VDC_TX_RING_SIZE >= 50)
blk_start_queue(port->disk->queue);
}
static int vdc_ack(struct vdc_port *port, void *msgbuf)
{
struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
struct vio_dring_data *pkt = msgbuf;
if (unlikely(pkt->dring_ident != dr->ident ||
pkt->start_idx != pkt->end_idx ||
pkt->start_idx >= VDC_TX_RING_SIZE))
return 0;
vdc_end_one(port, dr, pkt->start_idx);
return 0;
}
static int vdc_nack(struct vdc_port *port, void *msgbuf)
{
/* XXX Implement me XXX */
return 0;
}
static void vdc_event(void *arg, int event)
{
struct vdc_port *port = arg;
struct vio_driver_state *vio = &port->vio;
unsigned long flags;
int err;
spin_lock_irqsave(&vio->lock, flags);
if (unlikely(event == LDC_EVENT_RESET ||
event == LDC_EVENT_UP)) {
vio_link_state_change(vio, event);
spin_unlock_irqrestore(&vio->lock, flags);
return;
}
if (unlikely(event != LDC_EVENT_DATA_READY)) {
printk(KERN_WARNING PFX "Unexpected LDC event %d\n", event);
spin_unlock_irqrestore(&vio->lock, flags);
return;
}
err = 0;
while (1) {
union {
struct vio_msg_tag tag;
u64 raw[8];
} msgbuf;
err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
if (unlikely(err < 0)) {
if (err == -ECONNRESET)
vio_conn_reset(vio);
break;
}
if (err == 0)
break;
viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
msgbuf.tag.type,
msgbuf.tag.stype,
msgbuf.tag.stype_env,
msgbuf.tag.sid);
err = vio_validate_sid(vio, &msgbuf.tag);
if (err < 0)
break;
if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
err = vdc_ack(port, &msgbuf);
else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
err = vdc_nack(port, &msgbuf);
else
err = vdc_handle_unknown(port, &msgbuf);
} else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
err = vio_control_pkt_engine(vio, &msgbuf);
} else {
err = vdc_handle_unknown(port, &msgbuf);
}
if (err < 0)
break;
}
if (err < 0)
vdc_finish(&port->vio, err, WAITING_FOR_ANY);
spin_unlock_irqrestore(&vio->lock, flags);
}
static int __vdc_tx_trigger(struct vdc_port *port)
{
struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
struct vio_dring_data hdr = {
.tag = {
.type = VIO_TYPE_DATA,
.stype = VIO_SUBTYPE_INFO,
.stype_env = VIO_DRING_DATA,
.sid = vio_send_sid(&port->vio),
},
.dring_ident = dr->ident,
.start_idx = dr->prod,
.end_idx = dr->prod,
};
int err, delay;
hdr.seq = dr->snd_nxt;
delay = 1;
do {
err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
if (err > 0) {
dr->snd_nxt++;
break;
}
udelay(delay);
if ((delay <<= 1) > 128)
delay = 128;
} while (err == -EAGAIN);
return err;
}
static int __send_request(struct request *req)
{
struct vdc_port *port = req->rq_disk->private_data;
struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
struct scatterlist sg[port->ring_cookies];
struct vdc_req_entry *rqe;
struct vio_disk_desc *desc;
unsigned int map_perm;
int nsg, err, i;
u64 len;
u8 op;
map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
if (rq_data_dir(req) == READ) {
map_perm |= LDC_MAP_W;
op = VD_OP_BREAD;
} else {
map_perm |= LDC_MAP_R;
op = VD_OP_BWRITE;
}
sg_init_table(sg, port->ring_cookies);
nsg = blk_rq_map_sg(req->q, req, sg);
len = 0;
for (i = 0; i < nsg; i++)
len += sg[i].length;
desc = vio_dring_cur(dr);
err = ldc_map_sg(port->vio.lp, sg, nsg,
desc->cookies, port->ring_cookies,
map_perm);
if (err < 0) {
printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
return err;
}
rqe = &port->rq_arr[dr->prod];
rqe->req = req;
desc->hdr.ack = VIO_ACK_ENABLE;
desc->req_id = port->req_id;
desc->operation = op;
if (port->vdisk_type == VD_DISK_TYPE_DISK) {
desc->slice = 0xff;
} else {
desc->slice = 0;
}
desc->status = ~0;
desc->offset = (blk_rq_pos(req) << 9) / port->vdisk_block_size;
desc->size = len;
desc->ncookies = err;
/* This has to be a non-SMP write barrier because we are writing
* to memory which is shared with the peer LDOM.
*/
wmb();
desc->hdr.state = VIO_DESC_READY;
err = __vdc_tx_trigger(port);
if (err < 0) {
printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
} else {
port->req_id++;
dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
}
return err;
}
static void do_vdc_request(struct request_queue *rq)
{
struct request *req;
while ((req = blk_peek_request(rq)) != NULL) {
struct vdc_port *port;
struct vio_dring_state *dr;
port = req->rq_disk->private_data;
dr = &port->vio.drings[VIO_DRIVER_TX_RING];
if (unlikely(vdc_tx_dring_avail(dr) < 1))
goto wait;
blk_start_request(req);
if (__send_request(req) < 0) {
blk_requeue_request(rq, req);
wait:
/* Avoid pointless unplugs. */
blk_stop_queue(rq);
break;
}
}
}
static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
{
struct vio_dring_state *dr;
struct vio_completion comp;
struct vio_disk_desc *desc;
unsigned int map_perm;
unsigned long flags;
int op_len, err;
void *req_buf;
if (!(((u64)1 << (u64)op) & port->operations))
return -EOPNOTSUPP;
switch (op) {
case VD_OP_BREAD:
case VD_OP_BWRITE:
default:
return -EINVAL;
case VD_OP_FLUSH:
op_len = 0;
map_perm = 0;
break;
case VD_OP_GET_WCE:
op_len = sizeof(u32);
map_perm = LDC_MAP_W;
break;
case VD_OP_SET_WCE:
op_len = sizeof(u32);
map_perm = LDC_MAP_R;
break;
case VD_OP_GET_VTOC:
op_len = sizeof(struct vio_disk_vtoc);
map_perm = LDC_MAP_W;
break;
case VD_OP_SET_VTOC:
op_len = sizeof(struct vio_disk_vtoc);
map_perm = LDC_MAP_R;
break;
case VD_OP_GET_DISKGEOM:
op_len = sizeof(struct vio_disk_geom);
map_perm = LDC_MAP_W;
break;
case VD_OP_SET_DISKGEOM:
op_len = sizeof(struct vio_disk_geom);
map_perm = LDC_MAP_R;
break;
case VD_OP_SCSICMD:
op_len = 16;
map_perm = LDC_MAP_RW;
break;
case VD_OP_GET_DEVID:
op_len = sizeof(struct vio_disk_devid);
map_perm = LDC_MAP_W;
break;
case VD_OP_GET_EFI:
case VD_OP_SET_EFI:
return -EOPNOTSUPP;
break;
};
map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
op_len = (op_len + 7) & ~7;
req_buf = kzalloc(op_len, GFP_KERNEL);
if (!req_buf)
return -ENOMEM;
if (len > op_len)
len = op_len;
if (map_perm & LDC_MAP_R)
memcpy(req_buf, buf, len);
spin_lock_irqsave(&port->vio.lock, flags);
dr = &port->vio.drings[VIO_DRIVER_TX_RING];
/* XXX If we want to use this code generically we have to
* XXX handle TX ring exhaustion etc.
*/
desc = vio_dring_cur(dr);
err = ldc_map_single(port->vio.lp, req_buf, op_len,
desc->cookies, port->ring_cookies,
map_perm);
if (err < 0) {
spin_unlock_irqrestore(&port->vio.lock, flags);
kfree(req_buf);
return err;
}
init_completion(&comp.com);
comp.waiting_for = WAITING_FOR_GEN_CMD;
port->vio.cmp = &comp;
desc->hdr.ack = VIO_ACK_ENABLE;
desc->req_id = port->req_id;
desc->operation = op;
desc->slice = 0;
desc->status = ~0;
desc->offset = 0;
desc->size = op_len;
desc->ncookies = err;
/* This has to be a non-SMP write barrier because we are writing
* to memory which is shared with the peer LDOM.
*/
wmb();
desc->hdr.state = VIO_DESC_READY;
err = __vdc_tx_trigger(port);
if (err >= 0) {
port->req_id++;
dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
spin_unlock_irqrestore(&port->vio.lock, flags);
wait_for_completion(&comp.com);
err = comp.err;
} else {
port->vio.cmp = NULL;
spin_unlock_irqrestore(&port->vio.lock, flags);
}
if (map_perm & LDC_MAP_W)
memcpy(buf, req_buf, len);
kfree(req_buf);
return err;
}
static int vdc_alloc_tx_ring(struct vdc_port *port)
{
struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
unsigned long len, entry_size;
int ncookies;
void *dring;
entry_size = sizeof(struct vio_disk_desc) +
(sizeof(struct ldc_trans_cookie) * port->ring_cookies);
len = (VDC_TX_RING_SIZE * entry_size);
ncookies = VIO_MAX_RING_COOKIES;
dring = ldc_alloc_exp_dring(port->vio.lp, len,
dr->cookies, &ncookies,
(LDC_MAP_SHADOW |
LDC_MAP_DIRECT |
LDC_MAP_RW));
if (IS_ERR(dring))
return PTR_ERR(dring);
dr->base = dring;
dr->entry_size = entry_size;
dr->num_entries = VDC_TX_RING_SIZE;
dr->prod = dr->cons = 0;
dr->pending = VDC_TX_RING_SIZE;
dr->ncookies = ncookies;
return 0;
}
static void vdc_free_tx_ring(struct vdc_port *port)
{
struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
if (dr->base) {
ldc_free_exp_dring(port->vio.lp, dr->base,
(dr->entry_size * dr->num_entries),
dr->cookies, dr->ncookies);
dr->base = NULL;
dr->entry_size = 0;
dr->num_entries = 0;
dr->pending = 0;
dr->ncookies = 0;
}
}
static int probe_disk(struct vdc_port *port)
{
struct vio_completion comp;
struct request_queue *q;
struct gendisk *g;
int err;
init_completion(&comp.com);
comp.err = 0;
comp.waiting_for = WAITING_FOR_LINK_UP;
port->vio.cmp = &comp;
vio_port_up(&port->vio);
wait_for_completion(&comp.com);
if (comp.err)
return comp.err;
err = generic_request(port, VD_OP_GET_VTOC,
&port->label, sizeof(port->label));
if (err < 0) {
printk(KERN_ERR PFX "VD_OP_GET_VTOC returns error %d\n", err);
return err;
}
if (vdc_version_supported(port, 1, 1)) {
/* vdisk_size should be set during the handshake, if it wasn't
* then the underlying disk is reserved by another system
*/
if (port->vdisk_size == -1)
return -ENODEV;
} else {
struct vio_disk_geom geom;
err = generic_request(port, VD_OP_GET_DISKGEOM,
&geom, sizeof(geom));
if (err < 0) {
printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
"error %d\n", err);
return err;
}
port->vdisk_size = ((u64)geom.num_cyl *
(u64)geom.num_hd *
(u64)geom.num_sec);
}
q = blk_init_queue(do_vdc_request, &port->vio.lock);
if (!q) {
printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
port->vio.name);
return -ENOMEM;
}
g = alloc_disk(1 << PARTITION_SHIFT);
if (!g) {
printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
port->vio.name);
blk_cleanup_queue(q);
return -ENOMEM;
}
port->disk = g;
/* Each segment in a request is up to an aligned page in size. */
blk_queue_segment_boundary(q, PAGE_SIZE - 1);
blk_queue_max_segment_size(q, PAGE_SIZE);
blk_queue_max_segments(q, port->ring_cookies);
blk_queue_max_hw_sectors(q, port->max_xfer_size);
g->major = vdc_major;
g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
strcpy(g->disk_name, port->disk_name);
g->fops = &vdc_fops;
g->queue = q;
g->private_data = port;
g->driverfs_dev = &port->vio.vdev->dev;
set_capacity(g, port->vdisk_size);
if (vdc_version_supported(port, 1, 1)) {
switch (port->vdisk_mtype) {
case VD_MEDIA_TYPE_CD:
pr_info(PFX "Virtual CDROM %s\n", port->disk_name);
g->flags |= GENHD_FL_CD;
g->flags |= GENHD_FL_REMOVABLE;
set_disk_ro(g, 1);
break;
case VD_MEDIA_TYPE_DVD:
pr_info(PFX "Virtual DVD %s\n", port->disk_name);
g->flags |= GENHD_FL_CD;
g->flags |= GENHD_FL_REMOVABLE;
set_disk_ro(g, 1);
break;
case VD_MEDIA_TYPE_FIXED:
pr_info(PFX "Virtual Hard disk %s\n", port->disk_name);
break;
}
}
pr_info(PFX "%s: %u sectors (%u MB) protocol %d.%d\n",
g->disk_name,
port->vdisk_size, (port->vdisk_size >> (20 - 9)),
port->vio.ver.major, port->vio.ver.minor);
add_disk(g);
return 0;
}
static struct ldc_channel_config vdc_ldc_cfg = {
.event = vdc_event,
.mtu = 64,
.mode = LDC_MODE_UNRELIABLE,
};
static struct vio_driver_ops vdc_vio_ops = {
.send_attr = vdc_send_attr,
.handle_attr = vdc_handle_attr,
.handshake_complete = vdc_handshake_complete,
};
static void print_version(void)
{
static int version_printed;
if (version_printed++ == 0)
printk(KERN_INFO "%s", version);
}
static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
{
struct mdesc_handle *hp;
struct vdc_port *port;
int err;
print_version();
hp = mdesc_grab();
err = -ENODEV;
if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
printk(KERN_ERR PFX "Port id [%llu] too large.\n",
vdev->dev_no);
goto err_out_release_mdesc;
}
port = kzalloc(sizeof(*port), GFP_KERNEL);
err = -ENOMEM;
if (!port) {
printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
goto err_out_release_mdesc;
}
if (vdev->dev_no >= 26)
snprintf(port->disk_name, sizeof(port->disk_name),
VDCBLK_NAME "%c%c",
'a' + ((int)vdev->dev_no / 26) - 1,
'a' + ((int)vdev->dev_no % 26));
else
snprintf(port->disk_name, sizeof(port->disk_name),
VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
port->vdisk_size = -1;
err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
vdc_versions, ARRAY_SIZE(vdc_versions),
&vdc_vio_ops, port->disk_name);
if (err)
goto err_out_free_port;
port->vdisk_block_size = 512;
port->max_xfer_size = ((128 * 1024) / port->vdisk_block_size);
port->ring_cookies = ((port->max_xfer_size *
port->vdisk_block_size) / PAGE_SIZE) + 2;
err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
if (err)
goto err_out_free_port;
err = vdc_alloc_tx_ring(port);
if (err)
goto err_out_free_ldc;
err = probe_disk(port);
if (err)
goto err_out_free_tx_ring;
dev_set_drvdata(&vdev->dev, port);
mdesc_release(hp);
return 0;
err_out_free_tx_ring:
vdc_free_tx_ring(port);
err_out_free_ldc:
vio_ldc_free(&port->vio);
err_out_free_port:
kfree(port);
err_out_release_mdesc:
mdesc_release(hp);
return err;
}
static int vdc_port_remove(struct vio_dev *vdev)
{
struct vdc_port *port = dev_get_drvdata(&vdev->dev);
if (port) {
del_timer_sync(&port->vio.timer);
vdc_free_tx_ring(port);
vio_ldc_free(&port->vio);
dev_set_drvdata(&vdev->dev, NULL);
kfree(port);
}
return 0;
}
static const struct vio_device_id vdc_port_match[] = {
{
.type = "vdc-port",
},
{},
};
MODULE_DEVICE_TABLE(vio, vdc_port_match);
static struct vio_driver vdc_port_driver = {
.id_table = vdc_port_match,
.probe = vdc_port_probe,
.remove = vdc_port_remove,
.name = "vdc_port",
};
static int __init vdc_init(void)
{
int err;
err = register_blkdev(0, VDCBLK_NAME);
if (err < 0)
goto out_err;
vdc_major = err;
err = vio_register_driver(&vdc_port_driver);
if (err)
goto out_unregister_blkdev;
return 0;
out_unregister_blkdev:
unregister_blkdev(vdc_major, VDCBLK_NAME);
vdc_major = 0;
out_err:
return err;
}
static void __exit vdc_exit(void)
{
vio_unregister_driver(&vdc_port_driver);
unregister_blkdev(vdc_major, VDCBLK_NAME);
}
module_init(vdc_init);
module_exit(vdc_exit);