diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/staging/vhba/vhba.c |
Initial import
Diffstat (limited to 'drivers/staging/vhba/vhba.c')
-rw-r--r-- | drivers/staging/vhba/vhba.c | 1071 |
1 files changed, 1071 insertions, 0 deletions
diff --git a/drivers/staging/vhba/vhba.c b/drivers/staging/vhba/vhba.c new file mode 100644 index 000000000..4a14a10e9 --- /dev/null +++ b/drivers/staging/vhba/vhba.c @@ -0,0 +1,1071 @@ +/* + * vhba.c + * + * Copyright (C) 2007-2012 Chia-I Wu <b90201047 AT ntu DOT edu DOT tw> + * + * 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., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/highmem.h> +#include <linux/fs.h> +#include <linux/sched.h> +#include <linux/platform_device.h> +#include <linux/miscdevice.h> +#include <linux/poll.h> +#include <linux/slab.h> +#include <linux/version.h> +#ifdef CONFIG_COMPAT +#include <linux/compat.h> +#endif +#include <asm/uaccess.h> +#include <scsi/scsi.h> +#include <scsi/scsi_host.h> +#include <scsi/scsi_cmnd.h> +#include <scsi/scsi_device.h> + +/* scatterlist.page_link and sg_page() were introduced in 2.6.24 */ +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 24) +#define USE_SG_PAGE +#include <linux/scatterlist.h> +#endif + +MODULE_AUTHOR("Chia-I Wu"); +MODULE_VERSION(VHBA_VERSION); +MODULE_DESCRIPTION("Virtual SCSI HBA"); +MODULE_LICENSE("GPL"); + +#ifdef DEBUG +#define DPRINTK(fmt, args...) printk(KERN_DEBUG "%s: " fmt, __FUNCTION__, ## args) +#else +#define DPRINTK(fmt, args...) +#endif + +/* scmd_dbg was introduced in 3.15 */ +#ifndef scmd_dbg +#define scmd_dbg(scmd, fmt, a...) \ + dev_dbg(&(scmd)->device->sdev_gendev, fmt, ##a) +#endif + +#ifndef scmd_warn +#define scmd_warn(scmd, fmt, a...) \ + dev_warn(&(scmd)->device->sdev_gendev, fmt, ##a) +#endif + +#define VHBA_MAX_SECTORS_PER_IO 256 +#define VHBA_MAX_ID 32 +#define VHBA_CAN_QUEUE 32 +#define VHBA_INVALID_ID VHBA_MAX_ID + +#define DATA_TO_DEVICE(dir) ((dir) == DMA_TO_DEVICE || (dir) == DMA_BIDIRECTIONAL) +#define DATA_FROM_DEVICE(dir) ((dir) == DMA_FROM_DEVICE || (dir) == DMA_BIDIRECTIONAL) + + +/* SCSI macros were introduced in 2.6.23 */ +#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 23) +#define scsi_sg_count(cmd) ((cmd)->use_sg) +#define scsi_sglist(cmd) ((cmd)->request_buffer) +#define scsi_bufflen(cmd) ((cmd)->request_bufflen) +#define scsi_set_resid(cmd, to_read) {(cmd)->resid = (to_read);} +#endif + +/* 1-argument form of k[un]map_atomic was introduced in 2.6.37-rc1; + 2-argument form was deprecated in 3.4-rc1 */ +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 37) +#define vhba_kmap_atomic kmap_atomic +#define vhba_kunmap_atomic kunmap_atomic +#else +#define vhba_kmap_atomic(page) kmap_atomic(page, KM_USER0) +#define vhba_kunmap_atomic(page) kunmap_atomic(page, KM_USER0) +#endif + + +enum vhba_req_state { + VHBA_REQ_FREE, + VHBA_REQ_PENDING, + VHBA_REQ_READING, + VHBA_REQ_SENT, + VHBA_REQ_WRITING, +}; + +struct vhba_command { + struct scsi_cmnd *cmd; + int status; + struct list_head entry; +}; + +struct vhba_device { + uint id; + spinlock_t cmd_lock; + struct list_head cmd_list; + wait_queue_head_t cmd_wq; + atomic_t refcnt; +}; + +struct vhba_host { + struct Scsi_Host *shost; + spinlock_t cmd_lock; + int cmd_next; + struct vhba_command commands[VHBA_CAN_QUEUE]; + spinlock_t dev_lock; + struct vhba_device *devices[VHBA_MAX_ID]; + int num_devices; + DECLARE_BITMAP(chgmap, VHBA_MAX_ID); + int chgtype[VHBA_MAX_ID]; + struct work_struct scan_devices; +}; + +#define MAX_COMMAND_SIZE 16 + +struct vhba_request { + __u32 tag; + __u32 lun; + __u8 cdb[MAX_COMMAND_SIZE]; + __u8 cdb_len; + __u32 data_len; +}; + +struct vhba_response { + __u32 tag; + __u32 status; + __u32 data_len; +}; + +static struct vhba_command *vhba_alloc_command (void); +static void vhba_free_command (struct vhba_command *vcmd); + +static struct platform_device vhba_platform_device; + +static struct vhba_device *vhba_device_alloc (void) +{ + struct vhba_device *vdev; + + vdev = kzalloc(sizeof(struct vhba_device), GFP_KERNEL); + if (!vdev) { + return NULL; + } + + vdev->id = VHBA_INVALID_ID; + spin_lock_init(&vdev->cmd_lock); + INIT_LIST_HEAD(&vdev->cmd_list); + init_waitqueue_head(&vdev->cmd_wq); + atomic_set(&vdev->refcnt, 1); + + return vdev; +} + +static void vhba_device_put (struct vhba_device *vdev) +{ + if (atomic_dec_and_test(&vdev->refcnt)) { + kfree(vdev); + } +} + +static struct vhba_device *vhba_device_get (struct vhba_device *vdev) +{ + atomic_inc(&vdev->refcnt); + + return vdev; +} + +static int vhba_device_queue (struct vhba_device *vdev, struct scsi_cmnd *cmd) +{ + struct vhba_command *vcmd; + unsigned long flags; + + vcmd = vhba_alloc_command(); + if (!vcmd) { + return SCSI_MLQUEUE_HOST_BUSY; + } + + vcmd->cmd = cmd; + + spin_lock_irqsave(&vdev->cmd_lock, flags); + list_add_tail(&vcmd->entry, &vdev->cmd_list); + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + + wake_up_interruptible(&vdev->cmd_wq); + + return 0; +} + +static int vhba_device_dequeue (struct vhba_device *vdev, struct scsi_cmnd *cmd) +{ + struct vhba_command *vcmd; + int retval; + unsigned long flags; + + spin_lock_irqsave(&vdev->cmd_lock, flags); + list_for_each_entry(vcmd, &vdev->cmd_list, entry) { + if (vcmd->cmd == cmd) { + list_del_init(&vcmd->entry); + break; + } + } + + /* command not found */ + if (&vcmd->entry == &vdev->cmd_list) { + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + return SUCCESS; + } + + while (vcmd->status == VHBA_REQ_READING || vcmd->status == VHBA_REQ_WRITING) { + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + scmd_dbg(cmd, "wait for I/O before aborting\n"); + schedule_timeout(1); + spin_lock_irqsave(&vdev->cmd_lock, flags); + } + + retval = (vcmd->status == VHBA_REQ_SENT) ? FAILED : SUCCESS; + + vhba_free_command(vcmd); + + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + + return retval; +} + +static inline void vhba_scan_devices_add (struct vhba_host *vhost, int id) +{ + struct scsi_device *sdev; + + sdev = scsi_device_lookup(vhost->shost, 0, id, 0); + if (!sdev) { + scsi_add_device(vhost->shost, 0, id, 0); + } else { + dev_warn(&vhost->shost->shost_gendev, "tried to add an already-existing device 0:%d:0!\n", id); + scsi_device_put(sdev); + } +} + +static inline void vhba_scan_devices_remove (struct vhba_host *vhost, int id) +{ + struct scsi_device *sdev; + + sdev = scsi_device_lookup(vhost->shost, 0, id, 0); + if (sdev) { + scsi_remove_device(sdev); + scsi_device_put(sdev); + } else { + dev_warn(&vhost->shost->shost_gendev, "tried to remove non-existing device 0:%d:0!\n", id); + } +} + +static void vhba_scan_devices (struct work_struct *work) +{ + struct vhba_host *vhost = container_of(work, struct vhba_host, scan_devices); + unsigned long flags; + int id, change, exists; + + while (1) { + spin_lock_irqsave(&vhost->dev_lock, flags); + + id = find_first_bit(vhost->chgmap, vhost->shost->max_id); + if (id >= vhost->shost->max_id) { + spin_unlock_irqrestore(&vhost->dev_lock, flags); + break; + } + change = vhost->chgtype[id]; + exists = vhost->devices[id] != NULL; + + vhost->chgtype[id] = 0; + clear_bit(id, vhost->chgmap); + + spin_unlock_irqrestore(&vhost->dev_lock, flags); + + if (change < 0) { + dev_dbg(&vhost->shost->shost_gendev, "trying to remove target 0:%d:0\n", id); + vhba_scan_devices_remove(vhost, id); + } else if (change > 0) { + dev_dbg(&vhost->shost->shost_gendev, "trying to add target 0:%d:0\n", id); + vhba_scan_devices_add(vhost, id); + } else { + /* quick sequence of add/remove or remove/add; we determine + which one it was by checking if device structure exists */ + if (exists) { + /* remove followed by add: remove and (re)add */ + dev_dbg(&vhost->shost->shost_gendev, "trying to (re)add target 0:%d:0\n", id); + vhba_scan_devices_remove(vhost, id); + vhba_scan_devices_add(vhost, id); + } else { + /* add followed by remove: no-op */ + dev_dbg(&vhost->shost->shost_gendev, "no-op for target 0:%d:0\n", id); + } + } + } +} + +static int vhba_add_device (struct vhba_device *vdev) +{ + struct vhba_host *vhost; + int i; + unsigned long flags; + + vhost = platform_get_drvdata(&vhba_platform_device); + + vhba_device_get(vdev); + + spin_lock_irqsave(&vhost->dev_lock, flags); + if (vhost->num_devices >= vhost->shost->max_id) { + spin_unlock_irqrestore(&vhost->dev_lock, flags); + vhba_device_put(vdev); + return -EBUSY; + } + + for (i = 0; i < vhost->shost->max_id; i++) { + if (vhost->devices[i] == NULL) { + vdev->id = i; + vhost->devices[i] = vdev; + vhost->num_devices++; + set_bit(vdev->id, vhost->chgmap); + vhost->chgtype[vdev->id]++; + break; + } + } + spin_unlock_irqrestore(&vhost->dev_lock, flags); + + schedule_work(&vhost->scan_devices); + + return 0; +} + +static int vhba_remove_device (struct vhba_device *vdev) +{ + struct vhba_host *vhost; + unsigned long flags; + + vhost = platform_get_drvdata(&vhba_platform_device); + + spin_lock_irqsave(&vhost->dev_lock, flags); + set_bit(vdev->id, vhost->chgmap); + vhost->chgtype[vdev->id]--; + vhost->devices[vdev->id] = NULL; + vhost->num_devices--; + vdev->id = VHBA_INVALID_ID; + spin_unlock_irqrestore(&vhost->dev_lock, flags); + + vhba_device_put(vdev); + + schedule_work(&vhost->scan_devices); + + return 0; +} + +static struct vhba_device *vhba_lookup_device (int id) +{ + struct vhba_host *vhost; + struct vhba_device *vdev = NULL; + unsigned long flags; + + vhost = platform_get_drvdata(&vhba_platform_device); + + if (likely(id < vhost->shost->max_id)) { + spin_lock_irqsave(&vhost->dev_lock, flags); + vdev = vhost->devices[id]; + if (vdev) { + vdev = vhba_device_get(vdev); + } + + spin_unlock_irqrestore(&vhost->dev_lock, flags); + } + + return vdev; +} + +static struct vhba_command *vhba_alloc_command (void) +{ + struct vhba_host *vhost; + struct vhba_command *vcmd; + unsigned long flags; + int i; + + vhost = platform_get_drvdata(&vhba_platform_device); + + spin_lock_irqsave(&vhost->cmd_lock, flags); + + vcmd = vhost->commands + vhost->cmd_next++; + if (vcmd->status != VHBA_REQ_FREE) { + for (i = 0; i < vhost->shost->can_queue; i++) { + vcmd = vhost->commands + i; + + if (vcmd->status == VHBA_REQ_FREE) { + vhost->cmd_next = i + 1; + break; + } + } + + if (i == vhost->shost->can_queue) { + vcmd = NULL; + } + } + + if (vcmd) { + vcmd->status = VHBA_REQ_PENDING; + } + + vhost->cmd_next %= vhost->shost->can_queue; + + spin_unlock_irqrestore(&vhost->cmd_lock, flags); + + return vcmd; +} + +static void vhba_free_command (struct vhba_command *vcmd) +{ + struct vhba_host *vhost; + unsigned long flags; + + vhost = platform_get_drvdata(&vhba_platform_device); + + spin_lock_irqsave(&vhost->cmd_lock, flags); + vcmd->status = VHBA_REQ_FREE; + spin_unlock_irqrestore(&vhost->cmd_lock, flags); +} + +static int vhba_queuecommand_lck (struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *)) +{ + struct vhba_device *vdev; + int retval; + + scmd_dbg(cmd, "queue %lu\n", cmd->serial_number); + + vdev = vhba_lookup_device(cmd->device->id); + if (!vdev) { + scmd_dbg(cmd, "no such device\n"); + + cmd->result = DID_NO_CONNECT << 16; + done(cmd); + + return 0; + } + + cmd->scsi_done = done; + retval = vhba_device_queue(vdev, cmd); + + vhba_device_put(vdev); + + return retval; +} + +#ifdef DEF_SCSI_QCMD +DEF_SCSI_QCMD(vhba_queuecommand) +#else +#define vhba_queuecommand vhba_queuecommand_lck +#endif + +static int vhba_abort (struct scsi_cmnd *cmd) +{ + struct vhba_device *vdev; + int retval = SUCCESS; + + scmd_warn(cmd, "abort %lu\n", cmd->serial_number); + + vdev = vhba_lookup_device(cmd->device->id); + if (vdev) { + retval = vhba_device_dequeue(vdev, cmd); + vhba_device_put(vdev); + } else { + cmd->result = DID_NO_CONNECT << 16; + } + + return retval; +} + +static struct scsi_host_template vhba_template = { + .module = THIS_MODULE, + .name = "vhba", + .proc_name = "vhba", + .queuecommand = vhba_queuecommand, + .eh_abort_handler = vhba_abort, + .can_queue = VHBA_CAN_QUEUE, + .this_id = -1, + .cmd_per_lun = 1, + .max_sectors = VHBA_MAX_SECTORS_PER_IO, + .sg_tablesize = 256, +}; + +static ssize_t do_request (struct scsi_cmnd *cmd, char __user *buf, size_t buf_len) +{ + struct vhba_request vreq; + ssize_t ret; + + scmd_dbg(cmd, "request %lu, cdb 0x%x, bufflen %d, use_sg %d\n", + cmd->serial_number, cmd->cmnd[0], scsi_bufflen(cmd), scsi_sg_count(cmd)); + + ret = sizeof(vreq); + if (DATA_TO_DEVICE(cmd->sc_data_direction)) { + ret += scsi_bufflen(cmd); + } + + if (ret > buf_len) { + scmd_warn(cmd, "buffer too small (%zd < %zd) for a request\n", buf_len, ret); + return -EIO; + } + + vreq.tag = cmd->serial_number; + vreq.lun = cmd->device->lun; + memcpy(vreq.cdb, cmd->cmnd, MAX_COMMAND_SIZE); + vreq.cdb_len = cmd->cmd_len; + vreq.data_len = scsi_bufflen(cmd); + + if (copy_to_user(buf, &vreq, sizeof(vreq))) { + return -EFAULT; + } + + if (DATA_TO_DEVICE(cmd->sc_data_direction) && vreq.data_len) { + buf += sizeof(vreq); + + if (scsi_sg_count(cmd)) { + unsigned char buf_stack[64]; + unsigned char *kaddr, *uaddr, *kbuf; + struct scatterlist *sg = scsi_sglist(cmd); + int i; + + uaddr = (unsigned char *) buf; + + if (vreq.data_len > 64) { + kbuf = kmalloc(PAGE_SIZE, GFP_KERNEL); + } else { + kbuf = buf_stack; + } + + for (i = 0; i < scsi_sg_count(cmd); i++) { + size_t len = sg[i].length; + +#ifdef USE_SG_PAGE + kaddr = vhba_kmap_atomic(sg_page(&sg[i])); +#else + kaddr = vhba_kmap_atomic(sg[i].page); +#endif + memcpy(kbuf, kaddr + sg[i].offset, len); + vhba_kunmap_atomic(kaddr); + + if (copy_to_user(uaddr, kbuf, len)) { + if (kbuf != buf_stack) { + kfree(kbuf); + } + return -EFAULT; + } + uaddr += len; + } + + if (kbuf != buf_stack) { + kfree(kbuf); + } + } else { + if (copy_to_user(buf, scsi_sglist(cmd), vreq.data_len)) { + return -EFAULT; + } + } + } + + return ret; +} + +static ssize_t do_response (struct scsi_cmnd *cmd, const char __user *buf, size_t buf_len, struct vhba_response *res) +{ + ssize_t ret = 0; + + scmd_dbg(cmd, "response %lu, status %x, data len %d, use_sg %d\n", + cmd->serial_number, res->status, res->data_len, scsi_sg_count(cmd)); + + if (res->status) { + unsigned char sense_stack[SCSI_SENSE_BUFFERSIZE]; + + if (res->data_len > SCSI_SENSE_BUFFERSIZE) { + scmd_warn(cmd, "truncate sense (%d < %d)", SCSI_SENSE_BUFFERSIZE, res->data_len); + res->data_len = SCSI_SENSE_BUFFERSIZE; + } + + /* Copy via temporary buffer on stack in order to avoid problems + with PAX on grsecurity-enabled kernels */ + if (copy_from_user(sense_stack, buf, res->data_len)) { + return -EFAULT; + } + memcpy(cmd->sense_buffer, sense_stack, res->data_len); + + cmd->result = res->status; + + ret += res->data_len; + } else if (DATA_FROM_DEVICE(cmd->sc_data_direction) && scsi_bufflen(cmd)) { + size_t to_read; + + if (res->data_len > scsi_bufflen(cmd)) { + scmd_warn(cmd, "truncate data (%d < %d)\n", scsi_bufflen(cmd), res->data_len); + res->data_len = scsi_bufflen(cmd); + } + + to_read = res->data_len; + + if (scsi_sg_count(cmd)) { + unsigned char buf_stack[64]; + unsigned char *kaddr, *uaddr, *kbuf; + struct scatterlist *sg = scsi_sglist(cmd); + int i; + + uaddr = (unsigned char *)buf; + + if (res->data_len > 64) { + kbuf = kmalloc(PAGE_SIZE, GFP_KERNEL); + } else { + kbuf = buf_stack; + } + + for (i = 0; i < scsi_sg_count(cmd); i++) { + size_t len = (sg[i].length < to_read) ? sg[i].length : to_read; + + if (copy_from_user(kbuf, uaddr, len)) { + if (kbuf != buf_stack) { + kfree(kbuf); + } + return -EFAULT; + } + uaddr += len; + +#ifdef USE_SG_PAGE + kaddr = vhba_kmap_atomic(sg_page(&sg[i])); +#else + kaddr = vhba_kmap_atomic(sg[i].page); +#endif + memcpy(kaddr + sg[i].offset, kbuf, len); + vhba_kunmap_atomic(kaddr); + + to_read -= len; + if (to_read == 0) { + break; + } + } + + if (kbuf != buf_stack) { + kfree(kbuf); + } + } else { + if (copy_from_user(scsi_sglist(cmd), buf, res->data_len)) { + return -EFAULT; + } + + to_read -= res->data_len; + } + + scsi_set_resid(cmd, to_read); + + ret += res->data_len - to_read; + } + + return ret; +} + +static inline struct vhba_command *next_command (struct vhba_device *vdev) +{ + struct vhba_command *vcmd; + + list_for_each_entry(vcmd, &vdev->cmd_list, entry) { + if (vcmd->status == VHBA_REQ_PENDING) { + break; + } + } + + if (&vcmd->entry == &vdev->cmd_list) { + vcmd = NULL; + } + + return vcmd; +} + +static inline struct vhba_command *match_command (struct vhba_device *vdev, u32 tag) +{ + struct vhba_command *vcmd; + + list_for_each_entry(vcmd, &vdev->cmd_list, entry) { + if (vcmd->cmd->serial_number == tag) { + break; + } + } + + if (&vcmd->entry == &vdev->cmd_list) { + vcmd = NULL; + } + + return vcmd; +} + +static struct vhba_command *wait_command (struct vhba_device *vdev, unsigned long flags) +{ + struct vhba_command *vcmd; + DEFINE_WAIT(wait); + + while (!(vcmd = next_command(vdev))) { + if (signal_pending(current)) { + break; + } + + prepare_to_wait(&vdev->cmd_wq, &wait, TASK_INTERRUPTIBLE); + + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + + schedule(); + + spin_lock_irqsave(&vdev->cmd_lock, flags); + } + + finish_wait(&vdev->cmd_wq, &wait); + if (vcmd) { + vcmd->status = VHBA_REQ_READING; + } + + return vcmd; +} + +static ssize_t vhba_ctl_read (struct file *file, char __user *buf, size_t buf_len, loff_t *offset) +{ + struct vhba_device *vdev; + struct vhba_command *vcmd; + ssize_t ret; + unsigned long flags; + + vdev = file->private_data; + + /* Get next command */ + if (file->f_flags & O_NONBLOCK) { + /* Non-blocking variant */ + spin_lock_irqsave(&vdev->cmd_lock, flags); + vcmd = next_command(vdev); + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + + if (!vcmd) { + return -EWOULDBLOCK; + } + } else { + /* Blocking variant */ + spin_lock_irqsave(&vdev->cmd_lock, flags); + vcmd = wait_command(vdev, flags); + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + + if (!vcmd) { + return -ERESTARTSYS; + } + } + + ret = do_request(vcmd->cmd, buf, buf_len); + + spin_lock_irqsave(&vdev->cmd_lock, flags); + if (ret >= 0) { + vcmd->status = VHBA_REQ_SENT; + *offset += ret; + } else { + vcmd->status = VHBA_REQ_PENDING; + } + + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + + return ret; +} + +static ssize_t vhba_ctl_write (struct file *file, const char __user *buf, size_t buf_len, loff_t *offset) +{ + struct vhba_device *vdev; + struct vhba_command *vcmd; + struct vhba_response res; + ssize_t ret; + unsigned long flags; + + if (buf_len < sizeof(res)) { + return -EIO; + } + + if (copy_from_user(&res, buf, sizeof(res))) { + return -EFAULT; + } + + vdev = file->private_data; + + spin_lock_irqsave(&vdev->cmd_lock, flags); + vcmd = match_command(vdev, res.tag); + if (!vcmd || vcmd->status != VHBA_REQ_SENT) { + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + DPRINTK("not expecting response\n"); + return -EIO; + } + vcmd->status = VHBA_REQ_WRITING; + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + + ret = do_response(vcmd->cmd, buf + sizeof(res), buf_len - sizeof(res), &res); + + spin_lock_irqsave(&vdev->cmd_lock, flags); + if (ret >= 0) { + vcmd->cmd->scsi_done(vcmd->cmd); + ret += sizeof(res); + + /* don't compete with vhba_device_dequeue */ + if (!list_empty(&vcmd->entry)) { + list_del_init(&vcmd->entry); + vhba_free_command(vcmd); + } + } else { + vcmd->status = VHBA_REQ_SENT; + } + + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + + return ret; +} + +static long vhba_ctl_ioctl (struct file *file, unsigned int cmd, unsigned long arg) +{ + struct vhba_device *vdev = file->private_data; + struct vhba_host *vhost; + struct scsi_device *sdev; + + switch (cmd) { + case 0xBEEF001: { + vhost = platform_get_drvdata(&vhba_platform_device); + sdev = scsi_device_lookup(vhost->shost, 0, vdev->id, 0); + + if (sdev) { + int id[4] = { + sdev->host->host_no, + sdev->channel, + sdev->id, + sdev->lun + }; + + scsi_device_put(sdev); + + if (copy_to_user((void *)arg, id, sizeof(id))) { + return -EFAULT; + } + + return 0; + } else { + return -ENODEV; + } + } + } + + return -ENOTTY; +} + +#ifdef CONFIG_COMPAT +static long vhba_ctl_compat_ioctl (struct file *file, unsigned int cmd, unsigned long arg) +{ + unsigned long compat_arg = (unsigned long)compat_ptr(arg); + return vhba_ctl_ioctl(file, cmd, compat_arg); +} +#endif + +static unsigned int vhba_ctl_poll (struct file *file, poll_table *wait) +{ + struct vhba_device *vdev = file->private_data; + unsigned int mask = 0; + unsigned long flags; + + poll_wait(file, &vdev->cmd_wq, wait); + + spin_lock_irqsave(&vdev->cmd_lock, flags); + if (next_command(vdev)) { + mask |= POLLIN | POLLRDNORM; + } + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + + return mask; +} + +static int vhba_ctl_open (struct inode *inode, struct file *file) +{ + struct vhba_device *vdev; + int retval; + + DPRINTK("open\n"); + + /* check if vhba is probed */ + if (!platform_get_drvdata(&vhba_platform_device)) { + return -ENODEV; + } + + vdev = vhba_device_alloc(); + if (!vdev) { + return -ENOMEM; + } + + if (!(retval = vhba_add_device(vdev))) { + file->private_data = vdev; + } + + vhba_device_put(vdev); + + return retval; +} + +static int vhba_ctl_release (struct inode *inode, struct file *file) +{ + struct vhba_device *vdev; + struct vhba_command *vcmd; + unsigned long flags; + + DPRINTK("release\n"); + + vdev = file->private_data; + + vhba_device_get(vdev); + vhba_remove_device(vdev); + + spin_lock_irqsave(&vdev->cmd_lock, flags); + list_for_each_entry(vcmd, &vdev->cmd_list, entry) { + WARN_ON(vcmd->status == VHBA_REQ_READING || vcmd->status == VHBA_REQ_WRITING); + + scmd_warn(vcmd->cmd, "device released with command %lu\n", vcmd->cmd->serial_number); + vcmd->cmd->result = DID_NO_CONNECT << 16; + vcmd->cmd->scsi_done(vcmd->cmd); + + vhba_free_command(vcmd); + } + INIT_LIST_HEAD(&vdev->cmd_list); + spin_unlock_irqrestore(&vdev->cmd_lock, flags); + + vhba_device_put(vdev); + + return 0; +} + +static struct file_operations vhba_ctl_fops = { + .owner = THIS_MODULE, + .open = vhba_ctl_open, + .release = vhba_ctl_release, + .read = vhba_ctl_read, + .write = vhba_ctl_write, + .poll = vhba_ctl_poll, + .unlocked_ioctl = vhba_ctl_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = vhba_ctl_compat_ioctl, +#endif +}; + +static struct miscdevice vhba_miscdev = { + .minor = MISC_DYNAMIC_MINOR, + .name = "vhba_ctl", + .fops = &vhba_ctl_fops, +}; + +static int vhba_probe (struct platform_device *pdev) +{ + struct Scsi_Host *shost; + struct vhba_host *vhost; + int i; + + shost = scsi_host_alloc(&vhba_template, sizeof(struct vhba_host)); + if (!shost) { + return -ENOMEM; + } + + shost->max_id = VHBA_MAX_ID; + /* we don't support lun > 0 */ + shost->max_lun = 1; + shost->max_cmd_len = MAX_COMMAND_SIZE; + + vhost = (struct vhba_host *)shost->hostdata; + memset(vhost, 0, sizeof(*vhost)); + + vhost->shost = shost; + vhost->num_devices = 0; + spin_lock_init(&vhost->dev_lock); + spin_lock_init(&vhost->cmd_lock); + INIT_WORK(&vhost->scan_devices, vhba_scan_devices); + vhost->cmd_next = 0; + for (i = 0; i < vhost->shost->can_queue; i++) { + vhost->commands[i].status = VHBA_REQ_FREE; + } + + platform_set_drvdata(pdev, vhost); + + if (scsi_add_host(shost, &pdev->dev)) { + scsi_host_put(shost); + return -ENOMEM; + } + + return 0; +} + +static int vhba_remove (struct platform_device *pdev) +{ + struct vhba_host *vhost; + struct Scsi_Host *shost; + + vhost = platform_get_drvdata(pdev); + shost = vhost->shost; + + scsi_remove_host(shost); + scsi_host_put(shost); + + return 0; +} + +static void vhba_release (struct device * dev) +{ + return; +} + +static struct platform_device vhba_platform_device = { + .name = "vhba", + .id = -1, + .dev = { + .release = vhba_release, + }, +}; + +static struct platform_driver vhba_platform_driver = { + .driver = { + .owner = THIS_MODULE, + .name = "vhba", + }, + .probe = vhba_probe, + .remove = vhba_remove, +}; + +static int __init vhba_init (void) +{ + int ret; + + ret = platform_device_register(&vhba_platform_device); + if (ret < 0) { + return ret; + } + + ret = platform_driver_register(&vhba_platform_driver); + if (ret < 0) { + platform_device_unregister(&vhba_platform_device); + return ret; + } + + ret = misc_register(&vhba_miscdev); + if (ret < 0) { + platform_driver_unregister(&vhba_platform_driver); + platform_device_unregister(&vhba_platform_device); + return ret; + } + + return 0; +} + +static void __exit vhba_exit(void) +{ + misc_deregister(&vhba_miscdev); + platform_driver_unregister(&vhba_platform_driver); + platform_device_unregister(&vhba_platform_device); +} + +module_init(vhba_init); +module_exit(vhba_exit); + |