OpenCloudOS-Kernel/drivers/block/viodasd.c

819 lines
21 KiB
C

/* -*- linux-c -*-
* viodasd.c
* Authors: Dave Boutcher <boutcher@us.ibm.com>
* Ryan Arnold <ryanarn@us.ibm.com>
* Colin Devilbiss <devilbis@us.ibm.com>
* Stephen Rothwell <sfr@au1.ibm.com>
*
* (C) Copyright 2000-2004 IBM Corporation
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* This routine provides access to disk space (termed "DASD" in historical
* IBM terms) owned and managed by an OS/400 partition running on the
* same box as this Linux partition.
*
* All disk operations are performed by sending messages back and forth to
* the OS/400 partition.
*/
#include <linux/major.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/blkdev.h>
#include <linux/genhd.h>
#include <linux/hdreg.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/dma-mapping.h>
#include <linux/completion.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <asm/uaccess.h>
#include <asm/vio.h>
#include <asm/iseries/hv_types.h>
#include <asm/iseries/hv_lp_event.h>
#include <asm/iseries/hv_lp_config.h>
#include <asm/iseries/vio.h>
MODULE_DESCRIPTION("iSeries Virtual DASD");
MODULE_AUTHOR("Dave Boutcher");
MODULE_LICENSE("GPL");
/*
* We only support 7 partitions per physical disk....so with minor
* numbers 0-255 we get a maximum of 32 disks.
*/
#define VIOD_GENHD_NAME "iseries/vd"
#define VIOD_VERS "1.64"
#define VIOD_KERN_WARNING KERN_WARNING "viod: "
#define VIOD_KERN_INFO KERN_INFO "viod: "
enum {
PARTITION_SHIFT = 3,
MAX_DISKNO = HVMAXARCHITECTEDVIRTUALDISKS,
MAX_DISK_NAME = sizeof(((struct gendisk *)0)->disk_name)
};
static DEFINE_SPINLOCK(viodasd_spinlock);
#define VIOMAXREQ 16
#define VIOMAXBLOCKDMA 12
#define DEVICE_NO(cell) ((struct viodasd_device *)(cell) - &viodasd_devices[0])
struct open_data {
u64 disk_size;
u16 max_disk;
u16 cylinders;
u16 tracks;
u16 sectors;
u16 bytes_per_sector;
};
struct rw_data {
u64 offset;
struct {
u32 token;
u32 reserved;
u64 len;
} dma_info[VIOMAXBLOCKDMA];
};
struct vioblocklpevent {
struct HvLpEvent event;
u32 reserved;
u16 version;
u16 sub_result;
u16 disk;
u16 flags;
union {
struct open_data open_data;
struct rw_data rw_data;
u64 changed;
} u;
};
#define vioblockflags_ro 0x0001
enum vioblocksubtype {
vioblockopen = 0x0001,
vioblockclose = 0x0002,
vioblockread = 0x0003,
vioblockwrite = 0x0004,
vioblockflush = 0x0005,
vioblockcheck = 0x0007
};
struct viodasd_waitevent {
struct completion com;
int rc;
u16 sub_result;
int max_disk; /* open */
};
static const struct vio_error_entry viodasd_err_table[] = {
{ 0x0201, EINVAL, "Invalid Range" },
{ 0x0202, EINVAL, "Invalid Token" },
{ 0x0203, EIO, "DMA Error" },
{ 0x0204, EIO, "Use Error" },
{ 0x0205, EIO, "Release Error" },
{ 0x0206, EINVAL, "Invalid Disk" },
{ 0x0207, EBUSY, "Cant Lock" },
{ 0x0208, EIO, "Already Locked" },
{ 0x0209, EIO, "Already Unlocked" },
{ 0x020A, EIO, "Invalid Arg" },
{ 0x020B, EIO, "Bad IFS File" },
{ 0x020C, EROFS, "Read Only Device" },
{ 0x02FF, EIO, "Internal Error" },
{ 0x0000, 0, NULL },
};
/*
* Figure out the biggest I/O request (in sectors) we can accept
*/
#define VIODASD_MAXSECTORS (4096 / 512 * VIOMAXBLOCKDMA)
/*
* Number of disk I/O requests we've sent to OS/400
*/
static int num_req_outstanding;
/*
* This is our internal structure for keeping track of disk devices
*/
struct viodasd_device {
u16 cylinders;
u16 tracks;
u16 sectors;
u16 bytes_per_sector;
u64 size;
int read_only;
spinlock_t q_lock;
struct gendisk *disk;
struct device *dev;
} viodasd_devices[MAX_DISKNO];
/*
* External open entry point.
*/
static int viodasd_open(struct inode *ino, struct file *fil)
{
struct viodasd_device *d = ino->i_bdev->bd_disk->private_data;
HvLpEvent_Rc hvrc;
struct viodasd_waitevent we;
u16 flags = 0;
if (d->read_only) {
if ((fil != NULL) && (fil->f_mode & FMODE_WRITE))
return -EROFS;
flags = vioblockflags_ro;
}
init_completion(&we.com);
/* Send the open event to OS/400 */
hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
HvLpEvent_Type_VirtualIo,
viomajorsubtype_blockio | vioblockopen,
HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
viopath_sourceinst(viopath_hostLp),
viopath_targetinst(viopath_hostLp),
(u64)(unsigned long)&we, VIOVERSION << 16,
((u64)DEVICE_NO(d) << 48) | ((u64)flags << 32),
0, 0, 0);
if (hvrc != 0) {
printk(VIOD_KERN_WARNING "HV open failed %d\n", (int)hvrc);
return -EIO;
}
wait_for_completion(&we.com);
/* Check the return code */
if (we.rc != 0) {
const struct vio_error_entry *err =
vio_lookup_rc(viodasd_err_table, we.sub_result);
printk(VIOD_KERN_WARNING
"bad rc opening disk: %d:0x%04x (%s)\n",
(int)we.rc, we.sub_result, err->msg);
return -EIO;
}
return 0;
}
/*
* External release entry point.
*/
static int viodasd_release(struct inode *ino, struct file *fil)
{
struct viodasd_device *d = ino->i_bdev->bd_disk->private_data;
HvLpEvent_Rc hvrc;
/* Send the event to OS/400. We DON'T expect a response */
hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
HvLpEvent_Type_VirtualIo,
viomajorsubtype_blockio | vioblockclose,
HvLpEvent_AckInd_NoAck, HvLpEvent_AckType_ImmediateAck,
viopath_sourceinst(viopath_hostLp),
viopath_targetinst(viopath_hostLp),
0, VIOVERSION << 16,
((u64)DEVICE_NO(d) << 48) /* | ((u64)flags << 32) */,
0, 0, 0);
if (hvrc != 0)
printk(VIOD_KERN_WARNING "HV close call failed %d\n",
(int)hvrc);
return 0;
}
/* External ioctl entry point.
*/
static int viodasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
struct gendisk *disk = bdev->bd_disk;
struct viodasd_device *d = disk->private_data;
geo->sectors = d->sectors ? d->sectors : 0;
geo->heads = d->tracks ? d->tracks : 64;
geo->cylinders = d->cylinders ? d->cylinders :
get_capacity(disk) / (geo->cylinders * geo->heads);
return 0;
}
/*
* Our file operations table
*/
static struct block_device_operations viodasd_fops = {
.owner = THIS_MODULE,
.open = viodasd_open,
.release = viodasd_release,
.getgeo = viodasd_getgeo,
};
/*
* End a request
*/
static void viodasd_end_request(struct request *req, int uptodate,
int num_sectors)
{
if (end_that_request_first(req, uptodate, num_sectors))
return;
add_disk_randomness(req->rq_disk);
end_that_request_last(req, uptodate);
}
/*
* Send an actual I/O request to OS/400
*/
static int send_request(struct request *req)
{
u64 start;
int direction;
int nsg;
u16 viocmd;
HvLpEvent_Rc hvrc;
struct vioblocklpevent *bevent;
struct HvLpEvent *hev;
struct scatterlist sg[VIOMAXBLOCKDMA];
int sgindex;
int statindex;
struct viodasd_device *d;
unsigned long flags;
start = (u64)req->sector << 9;
if (rq_data_dir(req) == READ) {
direction = DMA_FROM_DEVICE;
viocmd = viomajorsubtype_blockio | vioblockread;
statindex = 0;
} else {
direction = DMA_TO_DEVICE;
viocmd = viomajorsubtype_blockio | vioblockwrite;
statindex = 1;
}
d = req->rq_disk->private_data;
/* Now build the scatter-gather list */
nsg = blk_rq_map_sg(req->q, req, sg);
nsg = dma_map_sg(d->dev, sg, nsg, direction);
spin_lock_irqsave(&viodasd_spinlock, flags);
num_req_outstanding++;
/* This optimization handles a single DMA block */
if (nsg == 1)
hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
HvLpEvent_Type_VirtualIo, viocmd,
HvLpEvent_AckInd_DoAck,
HvLpEvent_AckType_ImmediateAck,
viopath_sourceinst(viopath_hostLp),
viopath_targetinst(viopath_hostLp),
(u64)(unsigned long)req, VIOVERSION << 16,
((u64)DEVICE_NO(d) << 48), start,
((u64)sg_dma_address(&sg[0])) << 32,
sg_dma_len(&sg[0]));
else {
bevent = (struct vioblocklpevent *)
vio_get_event_buffer(viomajorsubtype_blockio);
if (bevent == NULL) {
printk(VIOD_KERN_WARNING
"error allocating disk event buffer\n");
goto error_ret;
}
/*
* Now build up the actual request. Note that we store
* the pointer to the request in the correlation
* token so we can match the response up later
*/
memset(bevent, 0, sizeof(struct vioblocklpevent));
hev = &bevent->event;
hev->flags = HV_LP_EVENT_VALID | HV_LP_EVENT_DO_ACK |
HV_LP_EVENT_INT;
hev->xType = HvLpEvent_Type_VirtualIo;
hev->xSubtype = viocmd;
hev->xSourceLp = HvLpConfig_getLpIndex();
hev->xTargetLp = viopath_hostLp;
hev->xSizeMinus1 =
offsetof(struct vioblocklpevent, u.rw_data.dma_info) +
(sizeof(bevent->u.rw_data.dma_info[0]) * nsg) - 1;
hev->xSourceInstanceId = viopath_sourceinst(viopath_hostLp);
hev->xTargetInstanceId = viopath_targetinst(viopath_hostLp);
hev->xCorrelationToken = (u64)req;
bevent->version = VIOVERSION;
bevent->disk = DEVICE_NO(d);
bevent->u.rw_data.offset = start;
/*
* Copy just the dma information from the sg list
* into the request
*/
for (sgindex = 0; sgindex < nsg; sgindex++) {
bevent->u.rw_data.dma_info[sgindex].token =
sg_dma_address(&sg[sgindex]);
bevent->u.rw_data.dma_info[sgindex].len =
sg_dma_len(&sg[sgindex]);
}
/* Send the request */
hvrc = HvCallEvent_signalLpEvent(&bevent->event);
vio_free_event_buffer(viomajorsubtype_blockio, bevent);
}
if (hvrc != HvLpEvent_Rc_Good) {
printk(VIOD_KERN_WARNING
"error sending disk event to OS/400 (rc %d)\n",
(int)hvrc);
goto error_ret;
}
spin_unlock_irqrestore(&viodasd_spinlock, flags);
return 0;
error_ret:
num_req_outstanding--;
spin_unlock_irqrestore(&viodasd_spinlock, flags);
dma_unmap_sg(d->dev, sg, nsg, direction);
return -1;
}
/*
* This is the external request processing routine
*/
static void do_viodasd_request(request_queue_t *q)
{
struct request *req;
/*
* If we already have the maximum number of requests
* outstanding to OS/400 just bail out. We'll come
* back later.
*/
while (num_req_outstanding < VIOMAXREQ) {
req = elv_next_request(q);
if (req == NULL)
return;
/* dequeue the current request from the queue */
blkdev_dequeue_request(req);
/* check that request contains a valid command */
if (!blk_fs_request(req)) {
viodasd_end_request(req, 0, req->hard_nr_sectors);
continue;
}
/* Try sending the request */
if (send_request(req) != 0)
viodasd_end_request(req, 0, req->hard_nr_sectors);
}
}
/*
* Probe a single disk and fill in the viodasd_device structure
* for it.
*/
static void probe_disk(struct viodasd_device *d)
{
HvLpEvent_Rc hvrc;
struct viodasd_waitevent we;
int dev_no = DEVICE_NO(d);
struct gendisk *g;
struct request_queue *q;
u16 flags = 0;
retry:
init_completion(&we.com);
/* Send the open event to OS/400 */
hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
HvLpEvent_Type_VirtualIo,
viomajorsubtype_blockio | vioblockopen,
HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
viopath_sourceinst(viopath_hostLp),
viopath_targetinst(viopath_hostLp),
(u64)(unsigned long)&we, VIOVERSION << 16,
((u64)dev_no << 48) | ((u64)flags<< 32),
0, 0, 0);
if (hvrc != 0) {
printk(VIOD_KERN_WARNING "bad rc on HV open %d\n", (int)hvrc);
return;
}
wait_for_completion(&we.com);
if (we.rc != 0) {
if (flags != 0)
return;
/* try again with read only flag set */
flags = vioblockflags_ro;
goto retry;
}
if (we.max_disk > (MAX_DISKNO - 1)) {
static int warned;
if (warned == 0) {
warned++;
printk(VIOD_KERN_INFO
"Only examining the first %d "
"of %d disks connected\n",
MAX_DISKNO, we.max_disk + 1);
}
}
/* Send the close event to OS/400. We DON'T expect a response */
hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
HvLpEvent_Type_VirtualIo,
viomajorsubtype_blockio | vioblockclose,
HvLpEvent_AckInd_NoAck, HvLpEvent_AckType_ImmediateAck,
viopath_sourceinst(viopath_hostLp),
viopath_targetinst(viopath_hostLp),
0, VIOVERSION << 16,
((u64)dev_no << 48) | ((u64)flags << 32),
0, 0, 0);
if (hvrc != 0) {
printk(VIOD_KERN_WARNING
"bad rc sending event to OS/400 %d\n", (int)hvrc);
return;
}
/* create the request queue for the disk */
spin_lock_init(&d->q_lock);
q = blk_init_queue(do_viodasd_request, &d->q_lock);
if (q == NULL) {
printk(VIOD_KERN_WARNING "cannot allocate queue for disk %d\n",
dev_no);
return;
}
g = alloc_disk(1 << PARTITION_SHIFT);
if (g == NULL) {
printk(VIOD_KERN_WARNING
"cannot allocate disk structure for disk %d\n",
dev_no);
blk_cleanup_queue(q);
return;
}
d->disk = g;
blk_queue_max_hw_segments(q, VIOMAXBLOCKDMA);
blk_queue_max_phys_segments(q, VIOMAXBLOCKDMA);
blk_queue_max_sectors(q, VIODASD_MAXSECTORS);
g->major = VIODASD_MAJOR;
g->first_minor = dev_no << PARTITION_SHIFT;
if (dev_no >= 26)
snprintf(g->disk_name, sizeof(g->disk_name),
VIOD_GENHD_NAME "%c%c",
'a' + (dev_no / 26) - 1, 'a' + (dev_no % 26));
else
snprintf(g->disk_name, sizeof(g->disk_name),
VIOD_GENHD_NAME "%c", 'a' + (dev_no % 26));
g->fops = &viodasd_fops;
g->queue = q;
g->private_data = d;
g->driverfs_dev = d->dev;
set_capacity(g, d->size >> 9);
printk(VIOD_KERN_INFO "disk %d: %lu sectors (%lu MB) "
"CHS=%d/%d/%d sector size %d%s\n",
dev_no, (unsigned long)(d->size >> 9),
(unsigned long)(d->size >> 20),
(int)d->cylinders, (int)d->tracks,
(int)d->sectors, (int)d->bytes_per_sector,
d->read_only ? " (RO)" : "");
/* register us in the global list */
add_disk(g);
}
/* returns the total number of scatterlist elements converted */
static int block_event_to_scatterlist(const struct vioblocklpevent *bevent,
struct scatterlist *sg, int *total_len)
{
int i, numsg;
const struct rw_data *rw_data = &bevent->u.rw_data;
static const int offset =
offsetof(struct vioblocklpevent, u.rw_data.dma_info);
static const int element_size = sizeof(rw_data->dma_info[0]);
numsg = ((bevent->event.xSizeMinus1 + 1) - offset) / element_size;
if (numsg > VIOMAXBLOCKDMA)
numsg = VIOMAXBLOCKDMA;
*total_len = 0;
memset(sg, 0, sizeof(sg[0]) * VIOMAXBLOCKDMA);
for (i = 0; (i < numsg) && (rw_data->dma_info[i].len > 0); ++i) {
sg_dma_address(&sg[i]) = rw_data->dma_info[i].token;
sg_dma_len(&sg[i]) = rw_data->dma_info[i].len;
*total_len += rw_data->dma_info[i].len;
}
return i;
}
/*
* Restart all queues, starting with the one _after_ the disk given,
* thus reducing the chance of starvation of higher numbered disks.
*/
static void viodasd_restart_all_queues_starting_from(int first_index)
{
int i;
for (i = first_index + 1; i < MAX_DISKNO; ++i)
if (viodasd_devices[i].disk)
blk_run_queue(viodasd_devices[i].disk->queue);
for (i = 0; i <= first_index; ++i)
if (viodasd_devices[i].disk)
blk_run_queue(viodasd_devices[i].disk->queue);
}
/*
* For read and write requests, decrement the number of outstanding requests,
* Free the DMA buffers we allocated.
*/
static int viodasd_handle_read_write(struct vioblocklpevent *bevent)
{
int num_sg, num_sect, pci_direction, total_len;
struct request *req;
struct scatterlist sg[VIOMAXBLOCKDMA];
struct HvLpEvent *event = &bevent->event;
unsigned long irq_flags;
struct viodasd_device *d;
int error;
spinlock_t *qlock;
num_sg = block_event_to_scatterlist(bevent, sg, &total_len);
num_sect = total_len >> 9;
if (event->xSubtype == (viomajorsubtype_blockio | vioblockread))
pci_direction = DMA_FROM_DEVICE;
else
pci_direction = DMA_TO_DEVICE;
req = (struct request *)bevent->event.xCorrelationToken;
d = req->rq_disk->private_data;
dma_unmap_sg(d->dev, sg, num_sg, pci_direction);
/*
* Since this is running in interrupt mode, we need to make sure
* we're not stepping on any global I/O operations
*/
spin_lock_irqsave(&viodasd_spinlock, irq_flags);
num_req_outstanding--;
spin_unlock_irqrestore(&viodasd_spinlock, irq_flags);
error = event->xRc != HvLpEvent_Rc_Good;
if (error) {
const struct vio_error_entry *err;
err = vio_lookup_rc(viodasd_err_table, bevent->sub_result);
printk(VIOD_KERN_WARNING "read/write error %d:0x%04x (%s)\n",
event->xRc, bevent->sub_result, err->msg);
num_sect = req->hard_nr_sectors;
}
qlock = req->q->queue_lock;
spin_lock_irqsave(qlock, irq_flags);
viodasd_end_request(req, !error, num_sect);
spin_unlock_irqrestore(qlock, irq_flags);
/* Finally, try to get more requests off of this device's queue */
viodasd_restart_all_queues_starting_from(DEVICE_NO(d));
return 0;
}
/* This routine handles incoming block LP events */
static void handle_block_event(struct HvLpEvent *event)
{
struct vioblocklpevent *bevent = (struct vioblocklpevent *)event;
struct viodasd_waitevent *pwe;
if (event == NULL)
/* Notification that a partition went away! */
return;
/* First, we should NEVER get an int here...only acks */
if (hvlpevent_is_int(event)) {
printk(VIOD_KERN_WARNING
"Yikes! got an int in viodasd event handler!\n");
if (hvlpevent_need_ack(event)) {
event->xRc = HvLpEvent_Rc_InvalidSubtype;
HvCallEvent_ackLpEvent(event);
}
}
switch (event->xSubtype & VIOMINOR_SUBTYPE_MASK) {
case vioblockopen:
/*
* Handle a response to an open request. We get all the
* disk information in the response, so update it. The
* correlation token contains a pointer to a waitevent
* structure that has a completion in it. update the
* return code in the waitevent structure and post the
* completion to wake up the guy who sent the request
*/
pwe = (struct viodasd_waitevent *)event->xCorrelationToken;
pwe->rc = event->xRc;
pwe->sub_result = bevent->sub_result;
if (event->xRc == HvLpEvent_Rc_Good) {
const struct open_data *data = &bevent->u.open_data;
struct viodasd_device *device =
&viodasd_devices[bevent->disk];
device->read_only =
bevent->flags & vioblockflags_ro;
device->size = data->disk_size;
device->cylinders = data->cylinders;
device->tracks = data->tracks;
device->sectors = data->sectors;
device->bytes_per_sector = data->bytes_per_sector;
pwe->max_disk = data->max_disk;
}
complete(&pwe->com);
break;
case vioblockclose:
break;
case vioblockread:
case vioblockwrite:
viodasd_handle_read_write(bevent);
break;
default:
printk(VIOD_KERN_WARNING "invalid subtype!");
if (hvlpevent_need_ack(event)) {
event->xRc = HvLpEvent_Rc_InvalidSubtype;
HvCallEvent_ackLpEvent(event);
}
}
}
/*
* Get the driver to reprobe for more disks.
*/
static ssize_t probe_disks(struct device_driver *drv, const char *buf,
size_t count)
{
struct viodasd_device *d;
for (d = viodasd_devices; d < &viodasd_devices[MAX_DISKNO]; d++) {
if (d->disk == NULL)
probe_disk(d);
}
return count;
}
static DRIVER_ATTR(probe, S_IWUSR, NULL, probe_disks);
static int viodasd_probe(struct vio_dev *vdev, const struct vio_device_id *id)
{
struct viodasd_device *d = &viodasd_devices[vdev->unit_address];
d->dev = &vdev->dev;
probe_disk(d);
if (d->disk == NULL)
return -ENODEV;
return 0;
}
static int viodasd_remove(struct vio_dev *vdev)
{
struct viodasd_device *d;
d = &viodasd_devices[vdev->unit_address];
if (d->disk) {
del_gendisk(d->disk);
blk_cleanup_queue(d->disk->queue);
put_disk(d->disk);
d->disk = NULL;
}
d->dev = NULL;
return 0;
}
/**
* viodasd_device_table: Used by vio.c to match devices that we
* support.
*/
static struct vio_device_id viodasd_device_table[] __devinitdata = {
{ "block", "IBM,iSeries-viodasd" },
{ "", "" }
};
MODULE_DEVICE_TABLE(vio, viodasd_device_table);
static struct vio_driver viodasd_driver = {
.id_table = viodasd_device_table,
.probe = viodasd_probe,
.remove = viodasd_remove,
.driver = {
.name = "viodasd",
.owner = THIS_MODULE,
}
};
/*
* Initialize the whole device driver. Handle module and non-module
* versions
*/
static int __init viodasd_init(void)
{
int rc;
/* Try to open to our host lp */
if (viopath_hostLp == HvLpIndexInvalid)
vio_set_hostlp();
if (viopath_hostLp == HvLpIndexInvalid) {
printk(VIOD_KERN_WARNING "invalid hosting partition\n");
return -EIO;
}
printk(VIOD_KERN_INFO "vers " VIOD_VERS ", hosting partition %d\n",
viopath_hostLp);
/* register the block device */
if (register_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME)) {
printk(VIOD_KERN_WARNING
"Unable to get major number %d for %s\n",
VIODASD_MAJOR, VIOD_GENHD_NAME);
return -EIO;
}
/* Actually open the path to the hosting partition */
if (viopath_open(viopath_hostLp, viomajorsubtype_blockio,
VIOMAXREQ + 2)) {
printk(VIOD_KERN_WARNING
"error opening path to host partition %d\n",
viopath_hostLp);
unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
return -EIO;
}
/* Initialize our request handler */
vio_setHandler(viomajorsubtype_blockio, handle_block_event);
rc = vio_register_driver(&viodasd_driver);
if (rc == 0)
driver_create_file(&viodasd_driver.driver, &driver_attr_probe);
return rc;
}
module_init(viodasd_init);
void viodasd_exit(void)
{
driver_remove_file(&viodasd_driver.driver, &driver_attr_probe);
vio_unregister_driver(&viodasd_driver);
vio_clearHandler(viomajorsubtype_blockio);
unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
viopath_close(viopath_hostLp, viomajorsubtype_blockio, VIOMAXREQ + 2);
}
module_exit(viodasd_exit);