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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/block/viodasd.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/block/viodasd.c')
-rw-r--r--drivers/block/viodasd.c846
1 files changed, 846 insertions, 0 deletions
diff --git a/drivers/block/viodasd.c b/drivers/block/viodasd.c
new file mode 100644
index 00000000000..46e56a25d2c
--- /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);