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-rw-r--r--drivers/block/sunvdc.c1249
1 files changed, 1249 insertions, 0 deletions
diff --git a/drivers/block/sunvdc.c b/drivers/block/sunvdc.c
new file mode 100644
index 000000000..9fa821fa7
--- /dev/null
+++ b/drivers/block/sunvdc.c
@@ -0,0 +1,1249 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* 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/blk-mq.h>
+#include <linux/hdreg.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 "1.2"
+#define DRV_MODULE_RELDATE "November 24, 2014"
+
+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 VDC_DEFAULT_BLK_SIZE 512
+
+#define MAX_XFER_BLKS (128 * 1024)
+#define MAX_XFER_SIZE (MAX_XFER_BLKS / VDC_DEFAULT_BLK_SIZE)
+#define MAX_RING_COOKIES ((MAX_XFER_BLKS / PAGE_SIZE) + 2)
+
+#define WAITING_FOR_LINK_UP 0x01
+#define WAITING_FOR_TX_SPACE 0x02
+#define WAITING_FOR_GEN_CMD 0x04
+#define WAITING_FOR_ANY -1
+
+#define VDC_MAX_RETRIES 10
+
+static struct workqueue_struct *sunvdc_wq;
+
+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;
+ u32 drain;
+
+ u64 ldc_timeout;
+ struct delayed_work ldc_reset_timer_work;
+ struct work_struct ldc_reset_work;
+
+ /* The server fills these in for us in the disk attribute
+ * ACK packet.
+ */
+ u64 operations;
+ u32 vdisk_size;
+ u8 vdisk_type;
+ u8 vdisk_mtype;
+ u32 vdisk_phys_blksz;
+
+ struct blk_mq_tag_set tag_set;
+
+ char disk_name[32];
+};
+
+static void vdc_ldc_reset(struct vdc_port *port);
+static void vdc_ldc_reset_work(struct work_struct *work);
+static void vdc_ldc_reset_timer_work(struct work_struct *work);
+
+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 = 2 },
+ { .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)
+{
+ struct vdc_port *port = bdev->bd_disk->private_data;
+ int i;
+
+ 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:
+ if (!vdc_version_supported(port, 1, 1))
+ return -EINVAL;
+ switch (port->vdisk_mtype) {
+ case VD_MEDIA_TYPE_CD:
+ case VD_MEDIA_TYPE_DVD:
+ return 0;
+ default:
+ 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,
+ .compat_ioctl = blkdev_compat_ptr_ioctl,
+};
+
+static void vdc_blk_queue_start(struct vdc_port *port)
+{
+ struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
+
+ /* restart blk queue when ring is half emptied. also called after
+ * handshake completes, so check for initial handshake before we've
+ * allocated a disk.
+ */
+ if (port->disk && vdc_tx_dring_avail(dr) * 100 / VDC_TX_RING_SIZE >= 50)
+ blk_mq_start_stopped_hw_queues(port->disk->queue, true);
+}
+
+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)
+{
+ struct vdc_port *port = to_vdc_port(vio);
+
+ cancel_delayed_work(&port->ldc_reset_timer_work);
+ vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
+ vdc_blk_queue_start(port);
+}
+
+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;
+
+ port->vdisk_phys_blksz = VDC_DEFAULT_BLK_SIZE;
+ if (vdc_version_supported(port, 1, 2))
+ port->vdisk_phys_blksz = pkt->phys_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 = vio_dring_next(dr, index);
+
+ req = rqe->req;
+ if (req == NULL) {
+ vdc_end_special(port, desc);
+ return;
+ }
+
+ rqe->req = NULL;
+
+ blk_mq_end_request(req, desc->status ? BLK_STS_IOERR : 0);
+
+ vdc_blk_queue_start(port);
+}
+
+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)) {
+ vio_link_state_change(vio, event);
+ queue_work(sunvdc_wq, &port->ldc_reset_work);
+ goto out;
+ }
+
+ if (unlikely(event == LDC_EVENT_UP)) {
+ vio_link_state_change(vio, event);
+ goto out;
+ }
+
+ if (unlikely(event != LDC_EVENT_DATA_READY)) {
+ pr_warn(PFX "Unexpected LDC event %d\n", event);
+ goto out;
+ }
+
+ 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);
+out:
+ 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;
+ int retries = 0;
+
+ 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;
+ if (retries++ > VDC_MAX_RETRIES)
+ break;
+ } while (err == -EAGAIN);
+
+ if (err == -ENOTCONN)
+ vdc_ldc_reset(port);
+ return err;
+}
+
+static int __send_request(struct request *req)
+{
+ struct vdc_port *port = req->q->disk->private_data;
+ struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
+ struct scatterlist sg[MAX_RING_COOKIES];
+ struct vdc_req_entry *rqe;
+ struct vio_disk_desc *desc;
+ unsigned int map_perm;
+ int nsg, err, i;
+ u64 len;
+ u8 op;
+
+ if (WARN_ON(port->ring_cookies > MAX_RING_COOKIES))
+ return -EINVAL;
+
+ 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 = vio_dring_next(dr, dr->prod);
+ }
+
+ return err;
+}
+
+static blk_status_t vdc_queue_rq(struct blk_mq_hw_ctx *hctx,
+ const struct blk_mq_queue_data *bd)
+{
+ struct vdc_port *port = hctx->queue->queuedata;
+ struct vio_dring_state *dr;
+ unsigned long flags;
+
+ dr = &port->vio.drings[VIO_DRIVER_TX_RING];
+
+ blk_mq_start_request(bd->rq);
+
+ spin_lock_irqsave(&port->vio.lock, flags);
+
+ /*
+ * Doing drain, just end the request in error
+ */
+ if (unlikely(port->drain)) {
+ spin_unlock_irqrestore(&port->vio.lock, flags);
+ return BLK_STS_IOERR;
+ }
+
+ if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
+ spin_unlock_irqrestore(&port->vio.lock, flags);
+ blk_mq_stop_hw_queue(hctx);
+ return BLK_STS_DEV_RESOURCE;
+ }
+
+ if (__send_request(bd->rq) < 0) {
+ spin_unlock_irqrestore(&port->vio.lock, flags);
+ return BLK_STS_IOERR;
+ }
+
+ spin_unlock_irqrestore(&port->vio.lock, flags);
+ return BLK_STS_OK;
+}
+
+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;
+ }
+
+ 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 = vio_dring_next(dr, dr->prod);
+ 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 vdc_port_up(struct vdc_port *port)
+{
+ struct vio_completion comp;
+
+ 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);
+ return comp.err;
+}
+
+static void vdc_port_down(struct vdc_port *port)
+{
+ ldc_disconnect(port->vio.lp);
+ ldc_unbind(port->vio.lp);
+ vdc_free_tx_ring(port);
+ vio_ldc_free(&port->vio);
+}
+
+static const struct blk_mq_ops vdc_mq_ops = {
+ .queue_rq = vdc_queue_rq,
+};
+
+static int probe_disk(struct vdc_port *port)
+{
+ struct request_queue *q;
+ struct gendisk *g;
+ int err;
+
+ err = vdc_port_up(port);
+ if (err)
+ return err;
+
+ /* Using version 1.2 means vdisk_phys_blksz should be set unless the
+ * disk is reserved by another system.
+ */
+ if (vdc_version_supported(port, 1, 2) && !port->vdisk_phys_blksz)
+ return -ENODEV;
+
+ 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);
+ }
+
+ err = blk_mq_alloc_sq_tag_set(&port->tag_set, &vdc_mq_ops,
+ VDC_TX_RING_SIZE, BLK_MQ_F_SHOULD_MERGE);
+ if (err)
+ return err;
+
+ g = blk_mq_alloc_disk(&port->tag_set, port);
+ if (IS_ERR(g)) {
+ printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
+ port->vio.name);
+ err = PTR_ERR(g);
+ goto out_free_tag;
+ }
+
+ port->disk = g;
+ q = g->queue;
+
+ /* 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;
+ g->minors = 1 << PARTITION_SHIFT;
+ strcpy(g->disk_name, port->disk_name);
+
+ g->fops = &vdc_fops;
+ g->queue = q;
+ g->private_data = port;
+
+ 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_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_REMOVABLE;
+ set_disk_ro(g, 1);
+ break;
+
+ case VD_MEDIA_TYPE_FIXED:
+ pr_info(PFX "Virtual Hard disk %s\n", port->disk_name);
+ break;
+ }
+ }
+
+ blk_queue_physical_block_size(q, port->vdisk_phys_blksz);
+
+ 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);
+
+ err = device_add_disk(&port->vio.vdev->dev, g, NULL);
+ if (err)
+ goto out_cleanup_disk;
+
+ return 0;
+
+out_cleanup_disk:
+ put_disk(g);
+out_free_tag:
+ blk_mq_free_tag_set(&port->tag_set);
+ return err;
+}
+
+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);
+}
+
+struct vdc_check_port_data {
+ int dev_no;
+ char *type;
+};
+
+static int vdc_device_probed(struct device *dev, void *arg)
+{
+ struct vio_dev *vdev = to_vio_dev(dev);
+ struct vdc_check_port_data *port_data;
+
+ port_data = (struct vdc_check_port_data *)arg;
+
+ if ((vdev->dev_no == port_data->dev_no) &&
+ (!(strcmp((char *)&vdev->type, port_data->type))) &&
+ dev_get_drvdata(dev)) {
+ /* This device has already been configured
+ * by vdc_port_probe()
+ */
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+/* Determine whether the VIO device is part of an mpgroup
+ * by locating all the virtual-device-port nodes associated
+ * with the parent virtual-device node for the VIO device
+ * and checking whether any of these nodes are vdc-ports
+ * which have already been configured.
+ *
+ * Returns true if this device is part of an mpgroup and has
+ * already been probed.
+ */
+static bool vdc_port_mpgroup_check(struct vio_dev *vdev)
+{
+ struct vdc_check_port_data port_data;
+ struct device *dev;
+
+ port_data.dev_no = vdev->dev_no;
+ port_data.type = (char *)&vdev->type;
+
+ dev = device_find_child(vdev->dev.parent, &port_data,
+ vdc_device_probed);
+
+ if (dev)
+ return true;
+
+ return false;
+}
+
+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;
+ const u64 *ldc_timeout;
+
+ print_version();
+
+ hp = mdesc_grab();
+ if (!hp)
+ return -ENODEV;
+
+ 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;
+ }
+
+ /* Check if this device is part of an mpgroup */
+ if (vdc_port_mpgroup_check(vdev)) {
+ printk(KERN_WARNING
+ "VIO: Ignoring extra vdisk port %s",
+ dev_name(&vdev->dev));
+ goto err_out_release_mdesc;
+ }
+
+ port = kzalloc(sizeof(*port), GFP_KERNEL);
+ if (!port) {
+ err = -ENOMEM;
+ 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;
+
+ /* Actual wall time may be double due to do_generic_file_read() doing
+ * a readahead I/O first, and once that fails it will try to read a
+ * single page.
+ */
+ ldc_timeout = mdesc_get_property(hp, vdev->mp, "vdc-timeout", NULL);
+ port->ldc_timeout = ldc_timeout ? *ldc_timeout : 0;
+ INIT_DELAYED_WORK(&port->ldc_reset_timer_work, vdc_ldc_reset_timer_work);
+ INIT_WORK(&port->ldc_reset_work, vdc_ldc_reset_work);
+
+ 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 = VDC_DEFAULT_BLK_SIZE;
+ port->max_xfer_size = MAX_XFER_SIZE;
+ port->ring_cookies = MAX_RING_COOKIES;
+
+ 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;
+
+ /* Note that the device driver_data is used to determine
+ * whether the port has been probed.
+ */
+ 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 void vdc_port_remove(struct vio_dev *vdev)
+{
+ struct vdc_port *port = dev_get_drvdata(&vdev->dev);
+
+ if (port) {
+ blk_mq_stop_hw_queues(port->disk->queue);
+
+ flush_work(&port->ldc_reset_work);
+ cancel_delayed_work_sync(&port->ldc_reset_timer_work);
+ del_timer_sync(&port->vio.timer);
+
+ del_gendisk(port->disk);
+ put_disk(port->disk);
+ blk_mq_free_tag_set(&port->tag_set);
+
+ vdc_free_tx_ring(port);
+ vio_ldc_free(&port->vio);
+
+ dev_set_drvdata(&vdev->dev, NULL);
+
+ kfree(port);
+ }
+}
+
+static void vdc_requeue_inflight(struct vdc_port *port)
+{
+ struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
+ u32 idx;
+
+ for (idx = dr->cons; idx != dr->prod; idx = vio_dring_next(dr, idx)) {
+ struct vio_disk_desc *desc = vio_dring_entry(dr, idx);
+ struct vdc_req_entry *rqe = &port->rq_arr[idx];
+ struct request *req;
+
+ ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
+ desc->hdr.state = VIO_DESC_FREE;
+ dr->cons = vio_dring_next(dr, idx);
+
+ req = rqe->req;
+ if (req == NULL) {
+ vdc_end_special(port, desc);
+ continue;
+ }
+
+ rqe->req = NULL;
+ blk_mq_requeue_request(req, false);
+ }
+}
+
+static void vdc_queue_drain(struct vdc_port *port)
+{
+ struct request_queue *q = port->disk->queue;
+
+ /*
+ * Mark the queue as draining, then freeze/quiesce to ensure
+ * that all existing requests are seen in ->queue_rq() and killed
+ */
+ port->drain = 1;
+ spin_unlock_irq(&port->vio.lock);
+
+ blk_mq_freeze_queue(q);
+ blk_mq_quiesce_queue(q);
+
+ spin_lock_irq(&port->vio.lock);
+ port->drain = 0;
+ blk_mq_unquiesce_queue(q);
+ blk_mq_unfreeze_queue(q);
+}
+
+static void vdc_ldc_reset_timer_work(struct work_struct *work)
+{
+ struct vdc_port *port;
+ struct vio_driver_state *vio;
+
+ port = container_of(work, struct vdc_port, ldc_reset_timer_work.work);
+ vio = &port->vio;
+
+ spin_lock_irq(&vio->lock);
+ if (!(port->vio.hs_state & VIO_HS_COMPLETE)) {
+ pr_warn(PFX "%s ldc down %llu seconds, draining queue\n",
+ port->disk_name, port->ldc_timeout);
+ vdc_queue_drain(port);
+ vdc_blk_queue_start(port);
+ }
+ spin_unlock_irq(&vio->lock);
+}
+
+static void vdc_ldc_reset_work(struct work_struct *work)
+{
+ struct vdc_port *port;
+ struct vio_driver_state *vio;
+ unsigned long flags;
+
+ port = container_of(work, struct vdc_port, ldc_reset_work);
+ vio = &port->vio;
+
+ spin_lock_irqsave(&vio->lock, flags);
+ vdc_ldc_reset(port);
+ spin_unlock_irqrestore(&vio->lock, flags);
+}
+
+static void vdc_ldc_reset(struct vdc_port *port)
+{
+ int err;
+
+ assert_spin_locked(&port->vio.lock);
+
+ pr_warn(PFX "%s ldc link reset\n", port->disk_name);
+ blk_mq_stop_hw_queues(port->disk->queue);
+ vdc_requeue_inflight(port);
+ vdc_port_down(port);
+
+ err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
+ if (err) {
+ pr_err(PFX "%s vio_ldc_alloc:%d\n", port->disk_name, err);
+ return;
+ }
+
+ err = vdc_alloc_tx_ring(port);
+ if (err) {
+ pr_err(PFX "%s vio_alloc_tx_ring:%d\n", port->disk_name, err);
+ goto err_free_ldc;
+ }
+
+ if (port->ldc_timeout)
+ mod_delayed_work(system_wq, &port->ldc_reset_timer_work,
+ round_jiffies(jiffies + HZ * port->ldc_timeout));
+ mod_timer(&port->vio.timer, round_jiffies(jiffies + HZ));
+ return;
+
+err_free_ldc:
+ vio_ldc_free(&port->vio);
+}
+
+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;
+
+ sunvdc_wq = alloc_workqueue("sunvdc", 0, 0);
+ if (!sunvdc_wq)
+ return -ENOMEM;
+
+ err = register_blkdev(0, VDCBLK_NAME);
+ if (err < 0)
+ goto out_free_wq;
+
+ 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_free_wq:
+ destroy_workqueue(sunvdc_wq);
+ return err;
+}
+
+static void __exit vdc_exit(void)
+{
+ vio_unregister_driver(&vdc_port_driver);
+ unregister_blkdev(vdc_major, VDCBLK_NAME);
+ destroy_workqueue(sunvdc_wq);
+}
+
+module_init(vdc_init);
+module_exit(vdc_exit);