diff options
Diffstat (limited to 'drivers/block/viodasd.c')
| -rw-r--r-- | drivers/block/viodasd.c | 846 |
1 files changed, 846 insertions, 0 deletions
diff --git a/drivers/block/viodasd.c b/drivers/block/viodasd.c new file mode 100644 index 000000000000..46e56a25d2c8 --- /dev/null +++ b/drivers/block/viodasd.c @@ -0,0 +1,846 @@ +/* -*- 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/HvTypes.h> +#include <asm/iSeries/HvLpEvent.h> +#include <asm/iSeries/HvLpConfig.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_GENHD_DEVFS_NAME "iseries/disc" + +#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_ioctl(struct inode *ino, struct file *fil, + unsigned int cmd, unsigned long arg) +{ + unsigned char sectors; + unsigned char heads; + unsigned short cylinders; + struct hd_geometry *geo; + struct gendisk *gendisk; + struct viodasd_device *d; + + switch (cmd) { + case HDIO_GETGEO: + geo = (struct hd_geometry *)arg; + if (geo == NULL) + return -EINVAL; + if (!access_ok(VERIFY_WRITE, geo, sizeof(*geo))) + return -EFAULT; + gendisk = ino->i_bdev->bd_disk; + d = gendisk->private_data; + sectors = d->sectors; + if (sectors == 0) + sectors = 32; + heads = d->tracks; + if (heads == 0) + heads = 64; + cylinders = d->cylinders; + if (cylinders == 0) + cylinders = get_capacity(gendisk) / (sectors * heads); + if (__put_user(sectors, &geo->sectors) || + __put_user(heads, &geo->heads) || + __put_user(cylinders, &geo->cylinders) || + __put_user(get_start_sect(ino->i_bdev), &geo->start)) + return -EFAULT; + return 0; + } + + return -EINVAL; +} + +/* + * Our file operations table + */ +static struct block_device_operations viodasd_fops = { + .owner = THIS_MODULE, + .open = viodasd_open, + .release = viodasd_release, + .ioctl = viodasd_ioctl, +}; + +/* + * 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); +} + +/* + * 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 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)); + bevent->event.xFlags.xValid = 1; + bevent->event.xFlags.xFunction = HvLpEvent_Function_Int; + bevent->event.xFlags.xAckInd = HvLpEvent_AckInd_DoAck; + bevent->event.xFlags.xAckType = HvLpEvent_AckType_ImmediateAck; + bevent->event.xType = HvLpEvent_Type_VirtualIo; + bevent->event.xSubtype = viocmd; + bevent->event.xSourceLp = HvLpConfig_getLpIndex(); + bevent->event.xTargetLp = viopath_hostLp; + bevent->event.xSizeMinus1 = + offsetof(struct vioblocklpevent, u.rw_data.dma_info) + + (sizeof(bevent->u.rw_data.dma_info[0]) * nsg) - 1; + bevent->event.xSourceInstanceId = + viopath_sourceinst(viopath_hostLp); + bevent->event.xTargetInstanceId = + viopath_targetinst(viopath_hostLp); + bevent->event.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)); + snprintf(g->devfs_name, sizeof(g->devfs_name), + "%s%d", VIOD_GENHD_DEVFS_NAME, dev_no); + 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 (event->xFlags.xFunction == HvLpEvent_Function_Int) { + printk(VIOD_KERN_WARNING + "Yikes! got an int in viodasd event handler!\n"); + if (event->xFlags.xAckInd == HvLpEvent_AckInd_DoAck) { + 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 (event->xFlags.xAckInd == HvLpEvent_AckInd_DoAck) { + 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 = { + { "viodasd", "" }, + { 0, } +}; + +MODULE_DEVICE_TABLE(vio, viodasd_device_table); +static struct vio_driver viodasd_driver = { + .name = "viodasd", + .id_table = viodasd_device_table, + .probe = viodasd_probe, + .remove = viodasd_remove +}; + +/* + * 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); |