diff options
Diffstat (limited to 'drivers/block/sunvdc.c')
| -rw-r--r-- | drivers/block/sunvdc.c | 1249 |
1 files changed, 1249 insertions, 0 deletions
diff --git a/drivers/block/sunvdc.c b/drivers/block/sunvdc.c new file mode 100644 index 0000000000..7bf4b48e22 --- /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, blk_mode_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 = ∁ + + 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 = ∁ + + 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); |