android_kernel_motorola_sm6225/drivers/block/viodasd.c
Tejun Heo 9934c8c045 block: implement and enforce request peek/start/fetch
Till now block layer allowed two separate modes of request execution.
A request is always acquired from the request queue via
elv_next_request().  After that, drivers are free to either dequeue it
or process it without dequeueing.  Dequeue allows elv_next_request()
to return the next request so that multiple requests can be in flight.

Executing requests without dequeueing has its merits mostly in
allowing drivers for simpler devices which can't do sg to deal with
segments only without considering request boundary.  However, the
benefit this brings is dubious and declining while the cost of the API
ambiguity is increasing.  Segment based drivers are usually for very
old or limited devices and as converting to dequeueing model isn't
difficult, it doesn't justify the API overhead it puts on block layer
and its more modern users.

Previous patches converted all block low level drivers to dequeueing
model.  This patch completes the API transition by...

* renaming elv_next_request() to blk_peek_request()

* renaming blkdev_dequeue_request() to blk_start_request()

* adding blk_fetch_request() which is combination of peek and start

* disallowing completion of queued (not started) requests

* applying new API to all LLDs

Renamings are for consistency and to break out of tree code so that
it's apparent that out of tree drivers need updating.

[ Impact: block request issue API cleanup, no functional change ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Mike Miller <mike.miller@hp.com>
Cc: unsik Kim <donari75@gmail.com>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Laurent Vivier <Laurent@lvivier.info>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Stefan Weinhuber <wein@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:52:18 +02:00

812 lines
22 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
*
* (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/scatterlist.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>
#include <asm/firmware.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 = FIELD_SIZEOF(struct gendisk, disk_name)
};
static DEFINE_SPINLOCK(viodasd_spinlock);
#define VIOMAXREQ 16
#define DEVICE_NO(cell) ((struct viodasd_device *)(cell) - &viodasd_devices[0])
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 block_device *bdev, fmode_t mode)
{
struct viodasd_device *d = bdev->bd_disk->private_data;
HvLpEvent_Rc hvrc;
struct viodasd_waitevent we;
u16 flags = 0;
if (d->read_only) {
if (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 gendisk *disk, fmode_t mode)
{
struct viodasd_device *d = 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 : 32;
geo->heads = d->tracks ? d->tracks : 64;
geo->cylinders = d->cylinders ? d->cylinders :
get_capacity(disk) / (geo->sectors * 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 error,
int num_sectors)
{
__blk_end_request(req, error, num_sectors << 9);
}
/*
* 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;
struct viodasd_device *d;
unsigned long flags;
start = (u64)blk_rq_pos(req) << 9;
if (rq_data_dir(req) == READ) {
direction = DMA_FROM_DEVICE;
viocmd = viomajorsubtype_blockio | vioblockread;
} else {
direction = DMA_TO_DEVICE;
viocmd = viomajorsubtype_blockio | vioblockwrite;
}
d = req->rq_disk->private_data;
/* Now build the scatter-gather list */
sg_init_table(sg, VIOMAXBLOCKDMA);
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(struct request_queue *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 = blk_fetch_request(q);
if (req == NULL)
return;
/* check that request contains a valid command */
if (!blk_fs_request(req)) {
viodasd_end_request(req, -EIO, blk_rq_sectors(req));
continue;
}
/* Try sending the request */
if (send_request(req) != 0)
viodasd_end_request(req, -EIO, blk_rq_sectors(req));
}
}
/*
* Probe a single disk and fill in the viodasd_device structure
* for it.
*/
static int 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 0;
}
wait_for_completion(&we.com);
if (we.rc != 0) {
if (flags != 0)
return 0;
/* 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 0;
}
if (d->dev == NULL) {
/* this is when we reprobe for new disks */
if (vio_create_viodasd(dev_no) == NULL) {
printk(VIOD_KERN_WARNING
"cannot allocate virtual device for disk %d\n",
dev_no);
return 0;
}
/*
* The vio_create_viodasd will have recursed into this
* routine with d->dev set to the new vio device and
* will finish the setup of the disk below.
*/
return 1;
}
/* 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 0;
}
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 0;
}
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);
return 1;
}
/* 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;
sg_init_table(sg, 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) ? 0 : -EIO;
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 = blk_rq_sectors(req);
}
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;
if (!probe_disk(d))
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,
}
};
static int need_delete_probe;
/*
* Initialize the whole device driver. Handle module and non-module
* versions
*/
static int __init viodasd_init(void)
{
int rc;
if (!firmware_has_feature(FW_FEATURE_ISERIES)) {
rc = -ENODEV;
goto early_fail;
}
/* 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");
rc = -EIO;
goto early_fail;
}
printk(VIOD_KERN_INFO "vers " VIOD_VERS ", hosting partition %d\n",
viopath_hostLp);
/* register the block device */
rc = register_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
if (rc) {
printk(VIOD_KERN_WARNING
"Unable to get major number %d for %s\n",
VIODASD_MAJOR, VIOD_GENHD_NAME);
goto early_fail;
}
/* Actually open the path to the hosting partition */
rc = viopath_open(viopath_hostLp, viomajorsubtype_blockio,
VIOMAXREQ + 2);
if (rc) {
printk(VIOD_KERN_WARNING
"error opening path to host partition %d\n",
viopath_hostLp);
goto unregister_blk;
}
/* Initialize our request handler */
vio_setHandler(viomajorsubtype_blockio, handle_block_event);
rc = vio_register_driver(&viodasd_driver);
if (rc) {
printk(VIOD_KERN_WARNING "vio_register_driver failed\n");
goto unset_handler;
}
/*
* If this call fails, it just means that we cannot dynamically
* add virtual disks, but the driver will still work fine for
* all existing disk, so ignore the failure.
*/
if (!driver_create_file(&viodasd_driver.driver, &driver_attr_probe))
need_delete_probe = 1;
return 0;
unset_handler:
vio_clearHandler(viomajorsubtype_blockio);
viopath_close(viopath_hostLp, viomajorsubtype_blockio, VIOMAXREQ + 2);
unregister_blk:
unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
early_fail:
return rc;
}
module_init(viodasd_init);
void __exit viodasd_exit(void)
{
if (need_delete_probe)
driver_remove_file(&viodasd_driver.driver, &driver_attr_probe);
vio_unregister_driver(&viodasd_driver);
vio_clearHandler(viomajorsubtype_blockio);
viopath_close(viopath_hostLp, viomajorsubtype_blockio, VIOMAXREQ + 2);
unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
}
module_exit(viodasd_exit);