text:
#include <linux/pktcdvd.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/compat.h>
#include <linux/kthread.h>
#include <linux/errno.h>
#include <linux/spinlock.h>
#include <linux/file.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/miscdevice.h>
#include <linux/freezer.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/scsi.h>
#include <linux/debugfs.h>
#include <linux/device.h>

#include <asm/uaccess.h>

#define DRIVER_NAME	"pktcdvd"

#if PACKET_DEBUG
#define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
#else
#define DPRINTK(fmt, args...)
#endif

#if PACKET_DEBUG > 1
#define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
#else
#define VPRINTK(fmt, args...)
#endif

#define MAX_SPEED 0xffff

#define ZONE(sector, pd) (((sector) + (pd)->offset) & \
			~(sector_t)((pd)->settings.size - 1))

static DEFINE_MUTEX(pktcdvd_mutex);
static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
static struct proc_dir_entry *pkt_proc;
static int pktdev_major;
static int write_congestion_on  = PKT_WRITE_CONGESTION_ON;
static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
static struct mutex ctl_mutex;	/* Serialize open/close/setup/teardown */
static mempool_t *psd_pool;

static struct class	*class_pktcdvd = NULL;    /* /sys/class/pktcdvd */
static struct dentry	*pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */

/* forward declaration */
static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
static int pkt_remove_dev(dev_t pkt_dev);
static int pkt_seq_show(struct seq_file *m, void *p);

/*
 * create and register a pktcdvd kernel object.
 */
static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
					const char* name,
					struct kobject* parent,
					struct kobj_type* ktype)
{
	struct pktcdvd_kobj *p;
	int error;

	p = kzalloc(sizeof(*p), GFP_KERNEL);
	if (!p)
		return NULL;
	p->pd = pd;
	error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
	if (error) {
		kobject_put(&p->kobj);
		return NULL;
	}
	kobject_uevent(&p->kobj, KOBJ_ADD);
	return p;
}
/*
 * remove a pktcdvd kernel object.
 */
static void pkt_kobj_remove(struct pktcdvd_kobj *p)
{
	if (p)
		kobject_put(&p->kobj);
}
/*
 * default release function for pktcdvd kernel objects.
 */
static void pkt_kobj_release(struct kobject *kobj)
{
	kfree(to_pktcdvdkobj(kobj));
}

/**********************************************************
 *
 * sysfs interface for pktcdvd
 * by (C) 2006  Thomas Maier <balagi@justmail.de>
 *
 **********************************************************/

#define DEF_ATTR(_obj,_name,_mode) \
	static struct attribute _obj = { .name = _name, .mode = _mode }

/**********************************************************
  /sys/class/pktcdvd/pktcdvd[0-7]/
                     stat/reset
                     stat/packets_started
                     stat/packets_finished
                     stat/kb_written
                     stat/kb_read
                     stat/kb_read_gather
                     write_queue/size
                     write_queue/congestion_off
                     write_queue/congestion_on
 **********************************************************/

DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);

static struct attribute *kobj_pkt_attrs_stat[] = {
	&kobj_pkt_attr_st1,
	&kobj_pkt_attr_st2,
	&kobj_pkt_attr_st3,
	&kobj_pkt_attr_st4,
	&kobj_pkt_attr_st5,
	&kobj_pkt_attr_st6,
	NULL
};

DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on",  0644);

static struct attribute *kobj_pkt_attrs_wqueue[] = {
	&kobj_pkt_attr_wq1,
	&kobj_pkt_attr_wq2,
	&kobj_pkt_attr_wq3,
	NULL
};

static ssize_t kobj_pkt_show(struct kobject *kobj,
			struct attribute *attr, char *data)
{
	struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
	int n = 0;
	int v;
	if (strcmp(attr->name, "packets_started") == 0) {
		n = sprintf(data, "%lu\n", pd->stats.pkt_started);

	} else if (strcmp(attr->name, "packets_finished") == 0) {
		n = sprintf(data, "%lu\n", pd->stats.pkt_ended);

	} else if (strcmp(attr->name, "kb_written") == 0) {
		n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);

	} else if (strcmp(attr->name, "kb_read") == 0) {
		n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);

	} else if (strcmp(attr->name, "kb_read_gather") == 0) {
		n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);

	} else if (strcmp(attr->name, "size") == 0) {
		spin_lock(&pd->lock);
		v = pd->bio_queue_size;
		spin_unlock(&pd->lock);
		n = sprintf(data, "%d\n", v);

	} else if (strcmp(attr->name, "congestion_off") == 0) {
		spin_lock(&pd->lock);
		v = pd->write_congestion_off;
		spin_unlock(&pd->lock);
		n = sprintf(data, "%d\n", v);

	} else if (strcmp(attr->name, "congestion_on") == 0) {
		spin_lock(&pd->lock);
		v = pd->write_congestion_on;
		spin_unlock(&pd->lock);
		n = sprintf(data, "%d\n", v);
	}
	return n;
}

static void init_write_congestion_marks(int* lo, int* hi)
{
	if (*hi > 0) {
		*hi = max(*hi, 500);
		*hi = min(*hi, 1000000);
		if (*lo <= 0)
			*lo = *hi - 100;
		else {
			*lo = min(*lo, *hi - 100);
			*lo = max(*lo, 100);
		}
	} else {
		*hi = -1;
		*lo = -1;
	}
}

static ssize_t kobj_pkt_store(struct kobject *kobj,
			struct attribute *attr,
			const char *data, size_t len)
{
	struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
	int val;

	if (strcmp(attr->name, "reset") == 0 && len > 0) {
		pd->stats.pkt_started = 0;
		pd->stats.pkt_ended = 0;
		pd->stats.secs_w = 0;
		pd->stats.secs_rg = 0;
		pd->stats.secs_r = 0;

	} else if (strcmp(attr->name, "congestion_off") == 0
		   && sscanf(data, "%d", &val) == 1) {
		spin_lock(&pd->lock);
		pd->write_congestion_off = val;
		init_write_congestion_marks(&pd->write_congestion_off,
					&pd->write_congestion_on);
		spin_unlock(&pd->lock);

	} else if (strcmp(attr->name, "congestion_on") == 0
		   && sscanf(data, "%d", &val) == 1) {
		spin_lock(&pd->lock);
		pd->write_congestion_on = val;
		init_write_congestion_marks(&pd->write_congestion_off,
					&pd->write_congestion_on);
		spin_unlock(&pd->lock);
	}
	return len;
}

static const struct sysfs_ops kobj_pkt_ops = {
	.show = kobj_pkt_show,
	.store = kobj_pkt_store
};
static struct kobj_type kobj_pkt_type_stat = {
	.release = pkt_kobj_release,
	.sysfs_ops = &kobj_pkt_ops,
	.default_attrs = kobj_pkt_attrs_stat
};
static struct kobj_type kobj_pkt_type_wqueue = {
	.release = pkt_kobj_release,
	.sysfs_ops = &kobj_pkt_ops,
	.default_attrs = kobj_pkt_attrs_wqueue
};

static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
{
	if (class_pktcdvd) {
		pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
					"%s", pd->name);
		if (IS_ERR(pd->dev))
			pd->dev = NULL;
	}
	if (pd->dev) {
		pd->kobj_stat = pkt_kobj_create(pd, "stat",
					&pd->dev->kobj,
					&kobj_pkt_type_stat);
		pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
					&pd->dev->kobj,
					&kobj_pkt_type_wqueue);
	}
}

static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
{
	pkt_kobj_remove(pd->kobj_stat);
	pkt_kobj_remove(pd->kobj_wqueue);
	if (class_pktcdvd)
		device_unregister(pd->dev);
}

/********************************************************************
  /sys/class/pktcdvd/
                     add            map block device
                     remove         unmap packet dev
                     device_map     show mappings
 *******************************************************************/

static void class_pktcdvd_release(struct class *cls)
{
	kfree(cls);
}
static ssize_t class_pktcdvd_show_map(struct class *c,
					struct class_attribute *attr,
					char *data)
{
	int n = 0;
	int idx;
	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
	for (idx = 0; idx < MAX_WRITERS; idx++) {
		struct pktcdvd_device *pd = pkt_devs[idx];
		if (!pd)
			continue;
		n += sprintf(data+n, "%s %u:%u %u:%u\n",
			pd->name,
			MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
			MAJOR(pd->bdev->bd_dev),
			MINOR(pd->bdev->bd_dev));
	}
	mutex_unlock(&ctl_mutex);
	return n;
}

static ssize_t class_pktcdvd_store_add(struct class *c,
					struct class_attribute *attr,
					const char *buf,
					size_t count)
{
	unsigned int major, minor;

	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
		/* pkt_setup_dev() expects caller to hold reference to self */
		if (!try_module_get(THIS_MODULE))
			return -ENODEV;

		pkt_setup_dev(MKDEV(major, minor), NULL);

		module_put(THIS_MODULE);

		return count;
	}

	return -EINVAL;
}

static ssize_t class_pktcdvd_store_remove(struct class *c,
					  struct class_attribute *attr,
					  const char *buf,
					size_t count)
{
	unsigned int major, minor;
	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
		pkt_remove_dev(MKDEV(major, minor));
		return count;
	}
	return -EINVAL;
}

static struct class_attribute class_pktcdvd_attrs[] = {
 __ATTR(add,            0200, NULL, class_pktcdvd_store_add),
 __ATTR(remove,         0200, NULL, class_pktcdvd_store_remove),
 __ATTR(device_map,     0444, class_pktcdvd_show_map, NULL),
 __ATTR_NULL
};

static int pkt_sysfs_init(void)
{
	int ret = 0;

	/*
	 * create control files in sysfs
	 * /sys/class/pktcdvd/...
	 */
	class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
	if (!class_pktcdvd)
		return -ENOMEM;
	class_pktcdvd->name = DRIVER_NAME;
	class_pktcdvd->owner = THIS_MODULE;
	class_pktcdvd->class_release = class_pktcdvd_release;
	class_pktcdvd->class_attrs = class_pktcdvd_attrs;
	ret = class_register(class_pktcdvd);
	if (ret) {
		kfree(class_pktcdvd);
		class_pktcdvd = NULL;
		printk(DRIVER_NAME": failed to create class pktcdvd\n");
		return ret;
	}
	return 0;
}

static void pkt_sysfs_cleanup(void)
{
	if (class_pktcdvd)
		class_destroy(class_pktcdvd);
	class_pktcdvd = NULL;
}

/********************************************************************
  entries in debugfs

  /sys/kernel/debug/pktcdvd[0-7]/
			info

 *******************************************************************/

static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
{
	return pkt_seq_show(m, p);
}

static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
{
	return single_open(file, pkt_debugfs_seq_show, inode->i_private);
}

static const struct file_operations debug_fops = {
	.open		= pkt_debugfs_fops_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
	.owner		= THIS_MODULE,
};

static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
{
	if (!pkt_debugfs_root)
		return;
	pd->dfs_f_info = NULL;
	pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
	if (IS_ERR(pd->dfs_d_root)) {
		pd->dfs_d_root = NULL;
		return;
	}
	pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
				pd->dfs_d_root, pd, &debug_fops);
	if (IS_ERR(pd->dfs_f_info)) {
		pd->dfs_f_info = NULL;
		return;
	}
}

static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
{
	if (!pkt_debugfs_root)
		return;
	if (pd->dfs_f_info)
		debugfs_remove(pd->dfs_f_info);
	pd->dfs_f_info = NULL;
	if (pd->dfs_d_root)
		debugfs_remove(pd->dfs_d_root);
	pd->dfs_d_root = NULL;
}

static void pkt_debugfs_init(void)
{
	pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
	if (IS_ERR(pkt_debugfs_root)) {
		pkt_debugfs_root = NULL;
		return;
	}
}

static void pkt_debugfs_cleanup(void)
{
	if (!pkt_debugfs_root)
		return;
	debugfs_remove(pkt_debugfs_root);
	pkt_debugfs_root = NULL;
}

/* ----------------------------------------------------------*/

static void pkt_bio_finished(struct pktcdvd_device *pd)
{
	BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
	if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
		VPRINTK(DRIVER_NAME": queue empty\n");
		atomic_set(&pd->iosched.attention, 1);
		wake_up(&pd->wqueue);
	}
}

/*
 * Allocate a packet_data struct
 */
static struct packet_data *pkt_alloc_packet_data(int frames)
{
	int i;
	struct packet_data *pkt;

	pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
	if (!pkt)
		goto no_pkt;

	pkt->frames = frames;
	pkt->w_bio = bio_kmalloc(GFP_KERNEL, frames);
	if (!pkt->w_bio)
		goto no_bio;

	for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
		pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
		if (!pkt->pages[i])
			goto no_page;
	}

	spin_lock_init(&pkt->lock);
	bio_list_init(&pkt->orig_bios);

	for (i = 0; i < frames; i++) {
		struct bio *bio = bio_kmalloc(GFP_KERNEL, 1);
		if (!bio)
			goto no_rd_bio;

		pkt->r_bios[i] = bio;
	}

	return pkt;

no_rd_bio:
	for (i = 0; i < frames; i++) {
		struct bio *bio = pkt->r_bios[i];
		if (bio)
			bio_put(bio);
	}

no_page:
	for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
		if (pkt->pages[i])
			__free_page(pkt->pages[i]);
	bio_put(pkt->w_bio);
no_bio:
	kfree(pkt);
no_pkt:
	return NULL;
}

/*
 * Free a packet_data struct
 */
static void pkt_free_packet_data(struct packet_data *pkt)
{
	int i;

	for (i = 0; i < pkt->frames; i++) {
		struct bio *bio = pkt->r_bios[i];
		if (bio)
			bio_put(bio);
	}
	for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
		__free_page(pkt->pages[i]);
	bio_put(pkt->w_bio);
	kfree(pkt);
}

static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
{
	struct packet_data *pkt, *next;

	BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));

	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
		pkt_free_packet_data(pkt);
	}
	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
}

static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
{
	struct packet_data *pkt;

	BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));

	while (nr_packets > 0) {
		pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
		if (!pkt) {
			pkt_shrink_pktlist(pd);
			return 0;
		}
		pkt->id = nr_packets;
		pkt->pd = pd;
		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
		nr_packets--;
	}
	return 1;
}

static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
{
	struct rb_node *n = rb_next(&node->rb_node);
	if (!n)
		return NULL;
	return rb_entry(n, struct pkt_rb_node, rb_node);
}

static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
{
	rb_erase(&node->rb_node, &pd->bio_queue);
	mempool_free(node, pd->rb_pool);
	pd->bio_queue_size--;
	BUG_ON(pd->bio_queue_size < 0);
}

/*
 * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 */
static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
{
	struct rb_node *n = pd->bio_queue.rb_node;
	struct rb_node *next;
	struct pkt_rb_node *tmp;

	if (!n) {
		BUG_ON(pd->bio_queue_size > 0);
		return NULL;
	}

	for (;;) {
		tmp = rb_entry(n, struct pkt_rb_node, rb_node);
		if (s <= tmp->bio->bi_sector)
			next = n->rb_left;
		else
			next = n->rb_right;
		if (!next)
			break;
		n = next;
	}

	if (s > tmp->bio->bi_sector) {
		tmp = pkt_rbtree_next(tmp);
		if (!tmp)
			return NULL;
	}
	BUG_ON(s > tmp->bio->bi_sector);
	return tmp;
}

/*
 * Insert a node into the pd->bio_queue rb tree.
 */
static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
{
	struct rb_node **p = &pd->bio_queue.rb_node;
	struct rb_node *parent = NULL;
	sector_t s = node->bio->bi_sector;
	struct pkt_rb_node *tmp;

	while (*p) {
		parent = *p;
		tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
		if (s < tmp->bio->bi_sector)
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}
	rb_link_node(&node->rb_node, parent, p);
	rb_insert_color(&node->rb_node, &pd->bio_queue);
	pd->bio_queue_size++;
}

/*
 * Send a packet_command to the underlying block device and
 * wait for completion.
 */
static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
{
	struct request_queue *q = bdev_get_queue(pd->bdev);
	struct request *rq;
	int ret = 0;

	rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
			     WRITE : READ, __GFP_WAIT);

	if (cgc->buflen) {
		if (blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, __GFP_WAIT))
			goto out;
	}

	rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
	memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);

	rq->timeout = 60*HZ;
	rq->cmd_type = REQ_TYPE_BLOCK_PC;
	if (cgc->quiet)
		rq->cmd_flags |= REQ_QUIET;

	blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
	if (rq->errors)
		ret = -EIO;
out:
	blk_put_request(rq);
	return ret;
}

/*
 * A generic sense dump / resolve mechanism should be implemented across
 * all ATAPI + SCSI devices.
 */
static void pkt_dump_sense(struct packet_command *cgc)
{
	static char *info[9] = { "No sense", "Recovered error", "Not ready",
				 "Medium error", "Hardware error", "Illegal request",
				 "Unit attention", "Data protect", "Blank check" };
	int i;
	struct request_sense *sense = cgc->sense;

	printk(DRIVER_NAME":");
	for (i = 0; i < CDROM_PACKET_SIZE; i++)
		printk(" %02x", cgc->cmd[i]);
	printk(" - ");

	if (sense == NULL) {
		printk("no sense\n");
		return;
	}

	printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);

	if (sense->sense_key > 8) {
		printk(" (INVALID)\n");
		return;
	}

	printk(" (%s)\n", info[sense->sense_key]);
}

/*
 * flush the drive cache to media
 */
static int pkt_flush_cache(struct pktcdvd_device *pd)
{
	struct packet_command cgc;

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
	cgc.cmd[0] = GPCMD_FLUSH_CACHE;
	cgc.quiet = 1;

	/*
	 * the IMMED bit -- we default to not setting it, although that
	 * would allow a much faster close, this is safer
	 */
#if 0
	cgc.cmd[1] = 1 << 1;
#endif
	return pkt_generic_packet(pd, &cgc);
}

/*
 * speed is given as the normal factor, e.g. 4 for 4x
 */
static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
				unsigned write_speed, unsigned read_speed)
{
	struct packet_command cgc;
	struct request_sense sense;
	int ret;

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
	cgc.sense = &sense;
	cgc.cmd[0] = GPCMD_SET_SPEED;
	cgc.cmd[2] = (read_speed >> 8) & 0xff;
	cgc.cmd[3] = read_speed & 0xff;
	cgc.cmd[4] = (write_speed >> 8) & 0xff;
	cgc.cmd[5] = write_speed & 0xff;

	if ((ret = pkt_generic_packet(pd, &cgc)))
		pkt_dump_sense(&cgc);

	return ret;
}

/*
 * Queue a bio for processing by the low-level CD device. Must be called
 * from process context.
 */
static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
{
	spin_lock(&pd->iosched.lock);
	if (bio_data_dir(bio) == READ)
		bio_list_add(&pd->iosched.read_queue, bio);
	else
		bio_list_add(&pd->iosched.write_queue, bio);
	spin_unlock(&pd->iosched.lock);

	atomic_set(&pd->iosched.attention, 1);
	wake_up(&pd->wqueue);
}

/*
 * Process the queued read/write requests. This function handles special
 * requirements for CDRW drives:
 * - A cache flush command must be inserted before a read request if the
 *   previous request was a write.
 * - Switching between reading and writing is slow, so don't do it more often
 *   than necessary.
 * - Optimize for throughput at the expense of latency. This means that streaming
 *   writes will never be interrupted by a read, but if the drive has to seek
 *   before the next write, switch to reading instead if there are any pending
 *   read requests.
 * - Set the read speed according to current usage pattern. When only reading
 *   from the device, it's best to use the highest possible read speed, but
 *   when switching often between reading and writing, it's better to have the
 *   same read and write speeds.
 */
static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
{

	if (atomic_read(&pd->iosched.attention) == 0)
		return;
	atomic_set(&pd->iosched.attention, 0);

	for (;;) {
		struct bio *bio;
		int reads_queued, writes_queued;

		spin_lock(&pd->iosched.lock);
		reads_queued = !bio_list_empty(&pd->iosched.read_queue);
		writes_queued = !bio_list_empty(&pd->iosched.write_queue);
		spin_unlock(&pd->iosched.lock);

		if (!reads_queued && !writes_queued)
			break;

		if (pd->iosched.writing) {
			int need_write_seek = 1;
			spin_lock(&pd->iosched.lock);
			bio = bio_list_peek(&pd->iosched.write_queue);
			spin_unlock(&pd->iosched.lock);
			if (bio && (bio->bi_sector == pd->iosched.last_write))
				need_write_seek = 0;
			if (need_write_seek && reads_queued) {
				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
					VPRINTK(DRIVER_NAME": write, waiting\n");
					break;
				}
				pkt_flush_cache(pd);
				pd->iosched.writing = 0;
			}
		} else {
			if (!reads_queued && writes_queued) {
				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
					VPRINTK(DRIVER_NAME": read, waiting\n");
					break;
				}
				pd->iosched.writing = 1;
			}
		}

		spin_lock(&pd->iosched.lock);
		if (pd->iosched.writing)
			bio = bio_list_pop(&pd->iosched.write_queue);
		else
			bio = bio_list_pop(&pd->iosched.read_queue);
		spin_unlock(&pd->iosched.lock);

		if (!bio)
			continue;

		if (bio_data_dir(bio) == READ)
			pd->iosched.successive_reads += bio->bi_size >> 10;
		else {
			pd->iosched.successive_reads = 0;
			pd->iosched.last_write = bio_end_sector(bio);
		}
		if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
			if (pd->read_speed == pd->write_speed) {
				pd->read_speed = MAX_SPEED;
				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
			}
		} else {
			if (pd->read_speed != pd->write_speed) {
				pd->read_speed = pd->write_speed;
				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
			}
		}

		atomic_inc(&pd->cdrw.pending_bios);
		generic_make_request(bio);
	}
}

/*
 * Special care is needed if the underlying block device has a small
 * max_phys_segments value.
 */
static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
{
	if ((pd->settings.size << 9) / CD_FRAMESIZE
	    <= queue_max_segments(q)) {
		/*
		 * The cdrom device can handle one segment/frame
		 */
		clear_bit(PACKET_MERGE_SEGS, &pd->flags);
		return 0;
	} else if ((pd->settings.size << 9) / PAGE_SIZE
		   <= queue_max_segments(q)) {
		/*
		 * We can handle this case at the expense of some extra memory
		 * copies during write operations
		 */
		set_bit(PACKET_MERGE_SEGS, &pd->flags);
		return 0;
	} else {
		printk(DRIVER_NAME": cdrom max_phys_segments too small\n");
		return -EIO;
	}
}

/*
 * Copy all data for this packet to pkt->pages[], so that
 * a) The number of required segments for the write bio is minimized, which
 *    is necessary for some scsi controllers.
 * b) The data can be used as cache to avoid read requests if we receive a
 *    new write request for the same zone.
 */
static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
{
	int f, p, offs;

	/* Copy all data to pkt->pages[] */
	p = 0;
	offs = 0;
	for (f = 0; f < pkt->frames; f++) {
		if (bvec[f].bv_page != pkt->pages[p]) {
			void *vfrom = kmap_atomic(bvec[f].bv_page) + bvec[f].bv_offset;
			void *vto = page_address(pkt->pages[p]) + offs;
			memcpy(vto, vfrom, CD_FRAMESIZE);
			kunmap_atomic(vfrom);
			bvec[f].bv_page = pkt->pages[p];
			bvec[f].bv_offset = offs;
		} else {
			BUG_ON(bvec[f].bv_offset != offs);
		}
		offs += CD_FRAMESIZE;
		if (offs >= PAGE_SIZE) {
			offs = 0;
			p++;
		}
	}
}

static void pkt_end_io_read(struct bio *bio, int err)
{
	struct packet_data *pkt = bio->bi_private;
	struct pktcdvd_device *pd = pkt->pd;
	BUG_ON(!pd);

	VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
		(unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);

	if (err)
		atomic_inc(&pkt->io_errors);
	if (atomic_dec_and_test(&pkt->io_wait)) {
		atomic_inc(&pkt->run_sm);
		wake_up(&pd->wqueue);
	}
	pkt_bio_finished(pd);
}

static void pkt_end_io_packet_write(struct bio *bio, int err)
{
	struct packet_data *pkt = bio->bi_private;
	struct pktcdvd_device *pd = pkt->pd;
	BUG_ON(!pd);

	VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);

	pd->stats.pkt_ended++;

	pkt_bio_finished(pd);
	atomic_dec(&pkt->io_wait);
	atomic_inc(&pkt->run_sm);
	wake_up(&pd->wqueue);
}

/*
 * Schedule reads for the holes in a packet
 */
static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
{
	int frames_read = 0;
	struct bio *bio;
	int f;
	char written[PACKET_MAX_SIZE];

	BUG_ON(bio_list_empty(&pkt->orig_bios));

	atomic_set(&pkt->io_wait, 0);
	atomic_set(&pkt->io_errors, 0);

	/*
	 * Figure out which frames we need to read before we can write.
	 */
	memset(written, 0, sizeof(written));
	spin_lock(&pkt->lock);
	bio_list_for_each(bio, &pkt->orig_bios) {
		int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
		int num_frames = bio->bi_size / CD_FRAMESIZE;
		pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
		BUG_ON(first_frame < 0);
		BUG_ON(first_frame + num_frames > pkt->frames);
		for (f = first_frame; f < first_frame + num_frames; f++)
			written[f] = 1;
	}
	spin_unlock(&pkt->lock);

	if (pkt->cache_valid) {
		VPRINTK("pkt_gather_data: zone %llx cached\n",
			(unsigned long long)pkt->sector);
		goto out_account;
	}

	/*
	 * Schedule reads for missing parts of the packet.
	 */
	for (f = 0; f < pkt->frames; f++) {
		int p, offset;

		if (written[f])
			continue;

		bio = pkt->r_bios[f];
		bio_reset(bio);
		bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
		bio->bi_bdev = pd->bdev;
		bio->bi_end_io = pkt_end_io_read;
		bio->bi_private = pkt;

		p = (f * CD_FRAMESIZE) / PAGE_SIZE;
		offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
		VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
			f, pkt->pages[p], offset);
		if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
			BUG();

		atomic_inc(&pkt->io_wait);
		bio->bi_rw = READ;
		pkt_queue_bio(pd, bio);
		frames_read++;
	}

out_account:
	VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
		frames_read, (unsigned long long)pkt->sector);
	pd->stats.pkt_started++;
	pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
}

/*
 * Find a packet matching zone, or the least recently used packet if
 * there is no match.
 */
static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
{
	struct packet_data *pkt;

	list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
		if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
			list_del_init(&pkt->list);
			if (pkt->sector != zone)
				pkt->cache_valid = 0;
			return pkt;
		}
	}
	BUG();
	return NULL;
}

static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
{
	if (pkt->cache_valid) {
		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
	} else {
		list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
	}
}

/*
 * recover a failed write, query for relocation if possible
 *
 * returns 1 if recovery is possible, or 0 if not
 *
 */
static int pkt_start_recovery(struct packet_data *pkt)
{
	/*
	 * FIXME. We need help from the file system to implement
	 * recovery handling.
	 */
	return 0;
#if 0
	struct request *rq = pkt->rq;
	struct pktcdvd_device *pd = rq->rq_disk->private_data;
	struct block_device *pkt_bdev;
	struct super_block *sb = NULL;
	unsigned long old_block, new_block;
	sector_t new_sector;

	pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
	if (pkt_bdev) {
		sb = get_super(pkt_bdev);
		bdput(pkt_bdev);
	}

	if (!sb)
		return 0;

	if (!sb->s_op->relocate_blocks)
		goto out;

	old_block = pkt->sector / (CD_FRAMESIZE >> 9);
	if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
		goto out;

	new_sector = new_block * (CD_FRAMESIZE >> 9);
	pkt->sector = new_sector;

	bio_reset(pkt->bio);
	pkt->bio->bi_bdev = pd->bdev;
	pkt->bio->bi_rw = REQ_WRITE;
	pkt->bio->bi_sector = new_sector;
	pkt->bio->bi_size = pkt->frames * CD_FRAMESIZE;
	pkt->bio->bi_vcnt = pkt->frames;

	pkt->bio->bi_end_io = pkt_end_io_packet_write;
	pkt->bio->bi_private = pkt;

	drop_super(sb);
	return 1;

out:
	drop_super(sb);
	return 0;
#endif
}

static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
{
#if PACKET_DEBUG > 1
	static const char *state_name[] = {
		"IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
	};
	enum packet_data_state old_state = pkt->state;
	VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
		state_name[old_state], state_name[state]);
#endif
	pkt->state = state;
}

/*
 * Scan the work queue to see if we can start a new packet.
 * returns non-zero if any work was done.
 */
static int pkt_handle_queue(struct pktcdvd_device *pd)
{
	struct packet_data *pkt, *p;
	struct bio *bio = NULL;
	sector_t zone = 0; /* Suppress gcc warning */
	struct pkt_rb_node *node, *first_node;
	struct rb_node *n;
	int wakeup;

	VPRINTK("handle_queue\n");

	atomic_set(&pd->scan_queue, 0);

	if (list_empty(&pd->cdrw.pkt_free_list)) {
		VPRINTK("handle_queue: no pkt\n");
		return 0;
	}

	/*
	 * Try to find a zone we are not already working on.
	 */
	spin_lock(&pd->lock);
	first_node = pkt_rbtree_find(pd, pd->current_sector);
	if (!first_node) {
		n = rb_first(&pd->bio_queue);
		if (n)
			first_node = rb_entry(n, struct pkt_rb_node, rb_node);
	}
	node = first_node;
	while (node) {
		bio = node->bio;
		zone = ZONE(bio->bi_sector, pd);
		list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
			if (p->sector == zone) {
				bio = NULL;
				goto try_next_bio;
			}
		}
		break;
try_next_bio:
		node = pkt_rbtree_next(node);
		if (!node) {
			n = rb_first(&pd->bio_queue);
			if (n)
				node = rb_entry(n, struct pkt_rb_node, rb_node);
		}
		if (node == first_node)
			node = NULL;
	}
	spin_unlock(&pd->lock);
	if (!bio) {
		VPRINTK("handle_queue: no bio\n");
		return 0;
	}

	pkt = pkt_get_packet_data(pd, zone);

	pd->current_sector = zone + pd->settings.size;
	pkt->sector = zone;
	BUG_ON(pkt->frames != pd->settings.size >> 2);
	pkt->write_size = 0;

	/*
	 * Scan work queue for bios in the same zone and link them
	 * to this packet.
	 */
	spin_lock(&pd->lock);
	VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
	while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
		bio = node->bio;
		VPRINTK("pkt_handle_queue: found zone=%llx\n",
			(unsigned long long)ZONE(bio->bi_sector, pd));
		if (ZONE(bio->bi_sector, pd) != zone)
			break;
		pkt_rbtree_erase(pd, node);
		spin_lock(&pkt->lock);
		bio_list_add(&pkt->orig_bios, bio);
		pkt->write_size += bio->bi_size / CD_FRAMESIZE;
		spin_unlock(&pkt->lock);
	}
	/* check write congestion marks, and if bio_queue_size is
	   below, wake up any waiters */
	wakeup = (pd->write_congestion_on > 0
	 		&& pd->bio_queue_size <= pd->write_congestion_off);
	spin_unlock(&pd->lock);
	if (wakeup) {
		clear_bdi_congested(&pd->disk->queue->backing_dev_info,
					BLK_RW_ASYNC);
	}

	pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
	pkt_set_state(pkt, PACKET_WAITING_STATE);
	atomic_set(&pkt->run_sm, 1);

	spin_lock(&pd->cdrw.active_list_lock);
	list_add(&pkt->list, &pd->cdrw.pkt_active_list);
	spin_unlock(&pd->cdrw.active_list_lock);

	return 1;
}

/*
 * Assemble a bio to write one packet and queue the bio for processing
 * by the underlying block device.
 */
static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
{
	int f;
	struct bio_vec *bvec = pkt->w_bio->bi_io_vec;

	bio_reset(pkt->w_bio);
	pkt->w_bio->bi_sector = pkt->sector;
	pkt->w_bio->bi_bdev = pd->bdev;
	pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
	pkt->w_bio->bi_private = pkt;

	/* XXX: locking? */
	for (f = 0; f < pkt->frames; f++) {
		bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
		bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
		if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
			BUG();
	}
	VPRINTK(DRIVER_NAME": vcnt=%d\n", pkt->w_bio->bi_vcnt);

	/*
	 * Fill-in bvec with data from orig_bios.
	 */
	spin_lock(&pkt->lock);
	bio_copy_data(pkt->w_bio, pkt->orig_bios.head);

	pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
	spin_unlock(&pkt->lock);

	VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
		pkt->write_size, (unsigned long long)pkt->sector);

	if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
		pkt_make_local_copy(pkt, bvec);
		pkt->cache_valid = 1;
	} else {
		pkt->cache_valid = 0;
	}

	/* Start the write request */
	atomic_set(&pkt->io_wait, 1);
	pkt->w_bio->bi_rw = WRITE;
	pkt_queue_bio(pd, pkt->w_bio);
}

static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
{
	struct bio *bio;

	if (!uptodate)
		pkt->cache_valid = 0;

	/* Finish all bios corresponding to this packet */
	while ((bio = bio_list_pop(&pkt->orig_bios)))
		bio_endio(bio, uptodate ? 0 : -EIO);
}

static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
{
	int uptodate;

	VPRINTK("run_state_machine: pkt %d\n", pkt->id);

	for (;;) {
		switch (pkt->state) {
		case PACKET_WAITING_STATE:
			if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
				return;

			pkt->sleep_time = 0;
			pkt_gather_data(pd, pkt);
			pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
			break;

		case PACKET_READ_WAIT_STATE:
			if (atomic_read(&pkt->io_wait) > 0)
				return;

			if (atomic_read(&pkt->io_errors) > 0) {
				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
			} else {
				pkt_start_write(pd, pkt);
			}
			break;

		case PACKET_WRITE_WAIT_STATE:
			if (atomic_read(&pkt->io_wait) > 0)
				return;

			if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
				pkt_set_state(pkt, PACKET_FINISHED_STATE);
			} else {
				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
			}
			break;

		case PACKET_RECOVERY_STATE:
			if (pkt_start_recovery(pkt)) {
				pkt_start_write(pd, pkt);
			} else {
				VPRINTK("No recovery possible\n");
				pkt_set_state(pkt, PACKET_FINISHED_STATE);
			}
			break;

		case PACKET_FINISHED_STATE:
			uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
			pkt_finish_packet(pkt, uptodate);
			return;

		default:
			BUG();
			break;
		}
	}
}

static void pkt_handle_packets(struct pktcdvd_device *pd)
{
	struct packet_data *pkt, *next;

	VPRINTK("pkt_handle_packets\n");

	/*
	 * Run state machine for active packets
	 */
	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
		if (atomic_read(&pkt->run_sm) > 0) {
			atomic_set(&pkt->run_sm, 0);
			pkt_run_state_machine(pd, pkt);
		}
	}

	/*
	 * Move no longer active packets to the free list
	 */
	spin_lock(&pd->cdrw.active_list_lock);
	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
		if (pkt->state == PACKET_FINISHED_STATE) {
			list_del(&pkt->list);
			pkt_put_packet_data(pd, pkt);
			pkt_set_state(pkt, PACKET_IDLE_STATE);
			atomic_set(&pd->scan_queue, 1);
		}
	}
	spin_unlock(&pd->cdrw.active_list_lock);
}

static void pkt_count_states(struct pktcdvd_device *pd, int *states)
{
	struct packet_data *pkt;
	int i;

	for (i = 0; i < PACKET_NUM_STATES; i++)
		states[i] = 0;

	spin_lock(&pd->cdrw.active_list_lock);
	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
		states[pkt->state]++;
	}
	spin_unlock(&pd->cdrw.active_list_lock);
}

/*
 * kcdrwd is woken up when writes have been queued for one of our
 * registered devices
 */
static int kcdrwd(void *foobar)
{
	struct pktcdvd_device *pd = foobar;
	struct packet_data *pkt;
	long min_sleep_time, residue;

	set_user_nice(current, -20);
	set_freezable();

	for (;;) {
		DECLARE_WAITQUEUE(wait, current);

		/*
		 * Wait until there is something to do
		 */
		add_wait_queue(&pd->wqueue, &wait);
		for (;;) {
			set_current_state(TASK_INTERRUPTIBLE);

			/* Check if we need to run pkt_handle_queue */
			if (atomic_read(&pd->scan_queue) > 0)
				goto work_to_do;

			/* Check if we need to run the state machine for some packet */
			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
				if (atomic_read(&pkt->run_sm) > 0)
					goto work_to_do;
			}

			/* Check if we need to process the iosched queues */
			if (atomic_read(&pd->iosched.attention) != 0)
				goto work_to_do;

			/* Otherwise, go to sleep */
			if (PACKET_DEBUG > 1) {
				int states[PACKET_NUM_STATES];
				pkt_count_states(pd, states);
				VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
					states[0], states[1], states[2], states[3],
					states[4], states[5]);
			}

			min_sleep_time = MAX_SCHEDULE_TIMEOUT;
			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
				if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
					min_sleep_time = pkt->sleep_time;
			}

			VPRINTK("kcdrwd: sleeping\n");
			residue = schedule_timeout(min_sleep_time);
			VPRINTK("kcdrwd: wake up\n");

			/* make swsusp happy with our thread */
			try_to_freeze();

			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
				if (!pkt->sleep_time)
					continue;
				pkt->sleep_time -= min_sleep_time - residue;
				if (pkt->sleep_time <= 0) {
					pkt->sleep_time = 0;
					atomic_inc(&pkt->run_sm);
				}
			}

			if (kthread_should_stop())
				break;
		}
work_to_do:
		set_current_state(TASK_RUNNING);
		remove_wait_queue(&pd->wqueue, &wait);

		if (kthread_should_stop())
			break;

		/*
		 * if pkt_handle_queue returns true, we can queue
		 * another request.
		 */
		while (pkt_handle_queue(pd))
			;

		/*
		 * Handle packet state machine
		 */
		pkt_handle_packets(pd);

		/*
		 * Handle iosched queues
		 */
		pkt_iosched_process_queue(pd);
	}

	return 0;
}

static void pkt_print_settings(struct pktcdvd_device *pd)
{
	printk(DRIVER_NAME": %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
	printk("%u blocks, ", pd->settings.size >> 2);
	printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
}

static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
{
	memset(cgc->cmd, 0, sizeof(cgc->cmd));

	cgc->cmd[0] = GPCMD_MODE_SENSE_10;
	cgc->cmd[2] = page_code | (page_control << 6);
	cgc->cmd[7] = cgc->buflen >> 8;
	cgc->cmd[8] = cgc->buflen & 0xff;
	cgc->data_direction = CGC_DATA_READ;
	return pkt_generic_packet(pd, cgc);
}

static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
{
	memset(cgc->cmd, 0, sizeof(cgc->cmd));
	memset(cgc->buffer, 0, 2);
	cgc->cmd[0] = GPCMD_MODE_SELECT_10;
	cgc->cmd[1] = 0x10;		/* PF */
	cgc->cmd[7] = cgc->buflen >> 8;
	cgc->cmd[8] = cgc->buflen & 0xff;
	cgc->data_direction = CGC_DATA_WRITE;
	return pkt_generic_packet(pd, cgc);
}

static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
{
	struct packet_command cgc;
	int ret;

	/* set up command and get the disc info */
	init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_DISC_INFO;
	cgc.cmd[8] = cgc.buflen = 2;
	cgc.quiet = 1;

	if ((ret = pkt_generic_packet(pd, &cgc)))
		return ret;

	/* not all drives have the same disc_info length, so requeue
	 * packet with the length the drive tells us it can supply
	 */
	cgc.buflen = be16_to_cpu(di->disc_information_length) +
		     sizeof(di->disc_information_length);

	if (cgc.buflen > sizeof(disc_information))
		cgc.buflen = sizeof(disc_information);

	cgc.cmd[8] = cgc.buflen;
	return pkt_generic_packet(pd, &cgc);
}

static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
{
	struct packet_command cgc;
	int ret;

	init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
	cgc.cmd[1] = type & 3;
	cgc.cmd[4] = (track & 0xff00) >> 8;
	cgc.cmd[5] = track & 0xff;
	cgc.cmd[8] = 8;
	cgc.quiet = 1;

	if ((ret = pkt_generic_packet(pd, &cgc)))
		return ret;

	cgc.buflen = be16_to_cpu(ti->track_information_length) +
		     sizeof(ti->track_information_length);

	if (cgc.buflen > sizeof(track_information))
		cgc.buflen = sizeof(track_information);

	cgc.cmd[8] = cgc.buflen;
	return pkt_generic_packet(pd, &cgc);
}

static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
						long *last_written)
{
	disc_information di;
	track_information ti;
	__u32 last_track;
	int ret = -1;

	if ((ret = pkt_get_disc_info(pd, &di)))
		return ret;

	last_track = (di.last_track_msb << 8) | di.last_track_lsb;
	if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
		return ret;

	/* if this track is blank, try the previous. */
	if (ti.blank) {
		last_track--;
		if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
			return ret;
	}

	/* if last recorded field is valid, return it. */
	if (ti.lra_v) {
		*last_written = be32_to_cpu(ti.last_rec_address);
	} else {
		/* make it up instead */
		*last_written = be32_to_cpu(ti.track_start) +
				be32_to_cpu(ti.track_size);
		if (ti.free_blocks)
			*last_written -= (be32_to_cpu(ti.free_blocks) + 7);
	}
	return 0;
}

/*
 * write mode select package based on pd->settings
 */
static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
{
	struct packet_command cgc;
	struct request_sense sense;
	write_param_page *wp;
	char buffer[128];
	int ret, size;

	/* doesn't apply to DVD+RW or DVD-RAM */
	if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
		return 0;

	memset(buffer, 0, sizeof(buffer));
	init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
	cgc.sense = &sense;
	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
		pkt_dump_sense(&cgc);
		return ret;
	}

	size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
	pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
	if (size > sizeof(buffer))
		size = sizeof(buffer);

	/*
	 * now get it all
	 */
	init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
	cgc.sense = &sense;
	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
		pkt_dump_sense(&cgc);
		return ret;
	}

	/*
	 * write page is offset header + block descriptor length
	 */
	wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];

	wp->fp = pd->settings.fp;
	wp->track_mode = pd->settings.track_mode;
	wp->write_type = pd->settings.write_type;
	wp->data_block_type = pd->settings.block_mode;

	wp->multi_session = 0;

#ifdef PACKET_USE_LS
	wp->link_size = 7;
	wp->ls_v = 1;
#endif

	if (wp->data_block_type == PACKET_BLOCK_MODE1) {
		wp->session_format = 0;
		wp->subhdr2 = 0x20;
	} else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
		wp->session_format = 0x20;
		wp->subhdr2 = 8;
#if 0
		wp->mcn[0] = 0x80;
		memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
#endif
	} else {
		/*
		 * paranoia
		 */
		printk(DRIVER_NAME": write mode wrong %d\n", wp->data_block_type);
		return 1;
	}
	wp->packet_size = cpu_to_be32(pd->settings.size >> 2);

	cgc.buflen = cgc.cmd[8] = size;
	if ((ret = pkt_mode_select(pd, &cgc))) {
		pkt_dump_sense(&cgc);
		return ret;
	}

	pkt_print_settings(pd);
	return 0;
}

/*
 * 1 -- we can write to this track, 0 -- we can't
 */
static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
{
	switch (pd->mmc3_profile) {
		case 0x1a: /* DVD+RW */
		case 0x12: /* DVD-RAM */
			/* The track is always writable on DVD+RW/DVD-RAM */
			return 1;
		default:
			break;
	}

	if (!ti->packet || !ti->fp)
		return 0;

	/*
	 * "good" settings as per Mt Fuji.
	 */
	if (ti->rt == 0 && ti->blank == 0)
		return 1;

	if (ti->rt == 0 && ti->blank == 1)
		return 1;

	if (ti->rt == 1 && ti->blank == 0)
		return 1;

	printk(DRIVER_NAME": bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
	return 0;
}

/*
 * 1 -- we can write to this disc, 0 -- we can't
 */
static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
{
	switch (pd->mmc3_profile) {
		case 0x0a: /* CD-RW */
		case 0xffff: /* MMC3 not supported */
			break;
		case 0x1a: /* DVD+RW */
		case 0x13: /* DVD-RW */
		case 0x12: /* DVD-RAM */
			return 1;
		default:
			VPRINTK(DRIVER_NAME": Wrong disc profile (%x)\n", pd->mmc3_profile);
			return 0;
	}

	/*
	 * for disc type 0xff we should probably reserve a new track.
	 * but i'm not sure, should we leave this to user apps? probably.
	 */
	if (di->disc_type == 0xff) {
		printk(DRIVER_NAME": Unknown disc. No track?\n");
		return 0;
	}

	if (di->disc_type != 0x20 && di->disc_type != 0) {
		printk(DRIVER_NAME": Wrong disc type (%x)\n", di->disc_type);
		return 0;
	}

	if (di->erasable == 0) {
		printk(DRIVER_NAME": Disc not erasable\n");
		return 0;
	}

	if (di->border_status == PACKET_SESSION_RESERVED) {
		printk(DRIVER_NAME": Can't write to last track (reserved)\n");
		return 0;
	}

	return 1;
}

static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
{
	struct packet_command cgc;
	unsigned char buf[12];
	disc_information di;
	track_information ti;
	int ret, track;

	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
	cgc.cmd[8] = 8;
	ret = pkt_generic_packet(pd, &cgc);
	pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];

	memset(&di, 0, sizeof(disc_information));
	memset(&ti, 0, sizeof(track_information));

	if ((ret = pkt_get_disc_info(pd, &di))) {
		printk("failed get_disc\n");
		return ret;
	}

	if (!pkt_writable_disc(pd, &di))
		return -EROFS;

	pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;

	track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
	if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
		printk(DRIVER_NAME": failed get_track\n");
		return ret;
	}

	if (!pkt_writable_track(pd, &ti)) {
		printk(DRIVER_NAME": can't write to this track\n");
		return -EROFS;
	}

	/*
	 * we keep packet size in 512 byte units, makes it easier to
	 * deal with request calculations.
	 */
	pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
	if (pd->settings.size == 0) {
		printk(DRIVER_NAME": detected zero packet size!\n");
		return -ENXIO;
	}
	if (pd->settings.size > PACKET_MAX_SECTORS) {
		printk(DRIVER_NAME": packet size is too big\n");
		return -EROFS;
	}
	pd->settings.fp = ti.fp;
	pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);

	if (ti.nwa_v) {
		pd->nwa = be32_to_cpu(ti.next_writable);
		set_bit(PACKET_NWA_VALID, &pd->flags);
	}

	/*
	 * in theory we could use lra on -RW media as well and just zero
	 * blocks that haven't been written yet, but in practice that
	 * is just a no-go. we'll use that for -R, naturally.
	 */
	if (ti.lra_v) {
		pd->lra = be32_to_cpu(ti.last_rec_address);
		set_bit(PACKET_LRA_VALID, &pd->flags);
	} else {
		pd->lra = 0xffffffff;
		set_bit(PACKET_LRA_VALID, &pd->flags);
	}

	/*
	 * fine for now
	 */
	pd->settings.link_loss = 7;
	pd->settings.write_type = 0;	/* packet */
	pd->settings.track_mode = ti.track_mode;

	/*
	 * mode1 or mode2 disc
	 */
	switch (ti.data_mode) {
		case PACKET_MODE1:
			pd->settings.block_mode = PACKET_BLOCK_MODE1;
			break;
		case PACKET_MODE2:
			pd->settings.block_mode = PACKET_BLOCK_MODE2;
			break;
		default:
			printk(DRIVER_NAME": unknown data mode\n");
			return -EROFS;
	}
	return 0;
}

/*
 * enable/disable write caching on drive
 */
static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
						int set)
{
	struct packet_command cgc;
	struct request_sense sense;
	unsigned char buf[64];
	int ret;

	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
	cgc.sense = &sense;
	cgc.buflen = pd->mode_offset + 12;

	/*
	 * caching mode page might not be there, so quiet this command
	 */
	cgc.quiet = 1;

	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
		return ret;

	buf[pd->mode_offset + 10] |= (!!set << 2);

	cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
	ret = pkt_mode_select(pd, &cgc);
	if (ret) {
		printk(DRIVER_NAME": write caching control failed\n");
		pkt_dump_sense(&cgc);
	} else if (!ret && set)
		printk(DRIVER_NAME": enabled write caching on %s\n", pd->name);
	return ret;
}

static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
{
	struct packet_command cgc;

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
	cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
	cgc.cmd[4] = lockflag ? 1 : 0;
	return pkt_generic_packet(pd, &cgc);
}

/*
 * Returns drive maximum write speed
 */
static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
						unsigned *write_speed)
{
	struct packet_command cgc;
	struct request_sense sense;
	unsigned char buf[256+18];
	unsigned char *cap_buf;
	int ret, offset;

	cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
	cgc.sense = &sense;

	ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
	if (ret) {
		cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
			     sizeof(struct mode_page_header);
		ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
		if (ret) {
			pkt_dump_sense(&cgc);
			return ret;
		}
	}

	offset = 20;			    /* Obsoleted field, used by older drives */
	if (cap_buf[1] >= 28)
		offset = 28;		    /* Current write speed selected */
	if (cap_buf[1] >= 30) {
		/* If the drive reports at least one "Logical Unit Write
		 * Speed Performance Descriptor Block", use the information
		 * in the first block. (contains the highest speed)
		 */
		int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
		if (num_spdb > 0)
			offset = 34;
	}

	*write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
	return 0;
}

/* These tables from cdrecord - I don't have orange book */
/* standard speed CD-RW (1-4x) */
static char clv_to_speed[16] = {
	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
	   0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};
/* high speed CD-RW (-10x) */
static char hs_clv_to_speed[16] = {
	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
	   0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};
/* ultra high speed CD-RW */
static char us_clv_to_speed[16] = {
	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
	   0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
};

/*
 * reads the maximum media speed from ATIP
 */
static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
						unsigned *speed)
{
	struct packet_command cgc;
	struct request_sense sense;
	unsigned char buf[64];
	unsigned int size, st, sp;
	int ret;

	init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
	cgc.sense = &sense;
	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
	cgc.cmd[1] = 2;
	cgc.cmd[2] = 4; /* READ ATIP */
	cgc.cmd[8] = 2;
	ret = pkt_generic_packet(pd, &cgc);
	if (ret) {
		pkt_dump_sense(&cgc);
		return ret;
	}
	size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
	if (size > sizeof(buf))
		size = sizeof(buf);

	init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
	cgc.sense = &sense;
	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
	cgc.cmd[1] = 2;
	cgc.cmd[2] = 4;
	cgc.cmd[8] = size;
	ret = pkt_generic_packet(pd, &cgc);
	if (ret) {
		pkt_dump_sense(&cgc);
		return ret;
	}

	if (!(buf[6] & 0x40)) {
		printk(DRIVER_NAME": Disc type is not CD-RW\n");
		return 1;
	}
	if (!(buf[6] & 0x4)) {
		printk(DRIVER_NAME": A1 values on media are not valid, maybe not CDRW?\n");
		return 1;
	}

	st = (buf[6] >> 3) & 0x7; /* disc sub-type */

	sp = buf[16] & 0xf; /* max speed from ATIP A1 field */

	/* Info from cdrecord */
	switch (st) {
		case 0: /* standard speed */
			*speed = clv_to_speed[sp];
			break;
		case 1: /* high speed */
			*speed = hs_clv_to_speed[sp];
			break;
		case 2: /* ultra high speed */
			*speed = us_clv_to_speed[sp];
			break;
		default:
			printk(DRIVER_NAME": Unknown disc sub-type %d\n",st);
			return 1;
	}
	if (*speed) {
		printk(DRIVER_NAME": Max. media speed: %d\n",*speed);
		return 0;
	} else {
		printk(DRIVER_NAME": Unknown speed %d for sub-type %d\n",sp,st);
		return 1;
	}
}

static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
{
	struct packet_command cgc;
	struct request_sense sense;
	int ret;

	VPRINTK(DRIVER_NAME": Performing OPC\n");

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
	cgc.sense = &sense;
	cgc.timeout = 60*HZ;
	cgc.cmd[0] = GPCMD_SEND_OPC;
	cgc.cmd[1] = 1;
	if ((ret = pkt_generic_packet(pd, &cgc)))
		pkt_dump_sense(&cgc);
	return ret;
}

static int pkt_open_write(struct pktcdvd_device *pd)
{
	int ret;
	unsigned int write_speed, media_write_speed, read_speed;

	if ((ret = pkt_probe_settings(pd))) {
		VPRINTK(DRIVER_NAME": %s failed probe\n", pd->name);
		return ret;
	}

	if ((ret = pkt_set_write_settings(pd))) {
		DPRINTK(DRIVER_NAME": %s failed saving write settings\n", pd->name);
		return -EIO;
	}

	pkt_write_caching(pd, USE_WCACHING);

	if ((ret = pkt_get_max_speed(pd, &write_speed)))
		write_speed = 16 * 177;
	switch (pd->mmc3_profile) {
		case 0x13: /* DVD-RW */
		case 0x1a: /* DVD+RW */
		case 0x12: /* DVD-RAM */
			DPRINTK(DRIVER_NAME": write speed %ukB/s\n", write_speed);
			break;
		default:
			if ((ret = pkt_media_speed(pd, &media_write_speed)))
				media_write_speed = 16;
			write_speed = min(write_speed, media_write_speed * 177);
			DPRINTK(DRIVER_NAME": write speed %ux\n", write_speed / 176);
			break;
	}
	read_speed = write_speed;

	if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
		DPRINTK(DRIVER_NAME": %s couldn't set write speed\n", pd->name);
		return -EIO;
	}
	pd->write_speed = write_speed;
	pd->read_speed = read_speed;

	if ((ret = pkt_perform_opc(pd))) {
		DPRINTK(DRIVER_NAME": %s Optimum Power Calibration failed\n", pd->name);
	}

	return 0;
}

/*
 * called at open time.
 */
static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
{
	int ret;
	long lba;
	struct request_queue *q;

	/*
	 * We need to re-open the cdrom device without O_NONBLOCK to be able
	 * to read/write from/to it. It is already opened in O_NONBLOCK mode
	 * so bdget() can't fail.
	 */
	bdget(pd->bdev->bd_dev);
	if ((ret = blkdev_get(pd->bdev, FMODE_READ | FMODE_EXCL, pd)))
		goto out;

	if ((ret = pkt_get_last_written(pd, &lba))) {
		printk(DRIVER_NAME": pkt_get_last_written failed\n");
		goto out_putdev;
	}

	set_capacity(pd->disk, lba << 2);
	set_capacity(pd->bdev->bd_disk, lba << 2);
	bd_set_size(pd->bdev, (loff_t)lba << 11);

	q = bdev_get_queue(pd->bdev);
	if (write) {
		if ((ret = pkt_open_write(pd)))
			goto out_putdev;
		/*
		 * Some CDRW drives can not handle writes larger than one packet,
		 * even if the size is a multiple of the packet size.
		 */
		spin_lock_irq(q->queue_lock);
		blk_queue_max_hw_sectors(q, pd->settings.size);
		spin_unlock_irq(q->queue_lock);
		set_bit(PACKET_WRITABLE, &pd->flags);
	} else {
		pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
		clear_bit(PACKET_WRITABLE, &pd->flags);
	}

	if ((ret = pkt_set_segment_merging(pd, q)))
		goto out_putdev;

	if (write) {
		if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
			printk(DRIVER_NAME": not enough memory for buffers\n");
			ret = -ENOMEM;
			goto out_putdev;
		}
		printk(DRIVER_NAME": %lukB available on disc\n", lba << 1);
	}

	return 0;

out_putdev:
	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
out:
	return ret;
}

/*
 * called when the device is closed. makes sure that the device flushes
 * the internal cache before we close.
 */
static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
{
	if (flush && pkt_flush_cache(pd))
		DPRINTK(DRIVER_NAME": %s not flushing cache\n", pd->name);

	pkt_lock_door(pd, 0);

	pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);

	pkt_shrink_pktlist(pd);
}

static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
{
	if (dev_minor >= MAX_WRITERS)
		return NULL;
	return pkt_devs[dev_minor];
}

static int pkt_open(struct block_device *bdev, fmode_t mode)
{
	struct pktcdvd_device *pd = NULL;
	int ret;

	VPRINTK(DRIVER_NAME": entering open\n");

	mutex_lock(&pktcdvd_mutex);
	mutex_lock(&ctl_mutex);
	pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
	if (!pd) {
		ret = -ENODEV;
		goto out;
	}
	BUG_ON(pd->refcnt < 0);

	pd->refcnt++;
	if (pd->refcnt > 1) {
		if ((mode & FMODE_WRITE) &&
		    !test_bit(PACKET_WRITABLE, &pd->flags)) {
			ret = -EBUSY;
			goto out_dec;
		}
	} else {
		ret = pkt_open_dev(pd, mode & FMODE_WRITE);
		if (ret)
			goto out_dec;
		/*
		 * needed here as well, since ext2 (among others) may change
		 * the blocksize at mount time
		 */
		set_blocksize(bdev, CD_FRAMESIZE);
	}

	mutex_unlock(&ctl_mutex);
	mutex_unlock(&pktcdvd_mutex);
	return 0;

out_dec:
	pd->refcnt--;
out:
	VPRINTK(DRIVER_NAME": failed open (%d)\n", ret);
	mutex_unlock(&ctl_mutex);
	mutex_unlock(&pktcdvd_mutex);
	return ret;
}

static void pkt_close(struct gendisk *disk, fmode_t mode)
{
	struct pktcdvd_device *pd = disk->private_data;

	mutex_lock(&pktcdvd_mutex);
	mutex_lock(&ctl_mutex);
	pd->refcnt--;
	BUG_ON(pd->refcnt < 0);
	if (pd->refcnt == 0) {
		int flush = test_bit(PACKET_WRITABLE, &pd->flags);
		pkt_release_dev(pd, flush);
	}
	mutex_unlock(&ctl_mutex);
	mutex_unlock(&pktcdvd_mutex);
}

static void pkt_end_io_read_cloned(struct bio *bio, int err)
{
	struct packet_stacked_data *psd = bio->bi_private;
	struct pktcdvd_device *pd = psd->pd;

	bio_put(bio);
	bio_endio(psd->bio, err);
	mempool_free(psd, psd_pool);
	pkt_bio_finished(pd);
}

static void pkt_make_request(struct request_queue *q, struct bio *bio)
{
	struct pktcdvd_device *pd;
	char b[BDEVNAME_SIZE];
	sector_t zone;
	struct packet_data *pkt;
	int was_empty, blocked_bio;
	struct pkt_rb_node *node;

	pd = q->queuedata;
	if (!pd) {
		printk(DRIVER_NAME": %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
		goto end_io;
	}

	/*
	 * Clone READ bios so we can have our own bi_end_io callback.
	 */
	if (bio_data_dir(bio) == READ) {
		struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
		struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);

		psd->pd = pd;
		psd->bio = bio;
		cloned_bio->bi_bdev = pd->bdev;
		cloned_bio->bi_private = psd;
		cloned_bio->bi_end_io = pkt_end_io_read_cloned;
		pd->stats.secs_r += bio_sectors(bio);
		pkt_queue_bio(pd, cloned_bio);
		return;
	}

	if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
		printk(DRIVER_NAME": WRITE for ro device %s (%llu)\n",
			pd->name, (unsigned long long)bio->bi_sector);
		goto end_io;
	}

	if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
		printk(DRIVER_NAME": wrong bio size\n");
		goto end_io;
	}

	blk_queue_bounce(q, &bio);

	zone = ZONE(bio->bi_sector, pd);
	VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
		(unsigned long long)bio->bi_sector,
		(unsigned long long)bio_end_sector(bio));

	/* Check if we have to split the bio */
	{
		struct bio_pair *bp;
		sector_t last_zone;
		int first_sectors;

		last_zone = ZONE(bio_end_sector(bio) - 1, pd);
		if (last_zone != zone) {
			BUG_ON(last_zone != zone + pd->settings.size);
			first_sectors = last_zone - bio->bi_sector;
			bp = bio_split(bio, first_sectors);
			BUG_ON(!bp);
			pkt_make_request(q, &bp->bio1);
			pkt_make_request(q, &bp->bio2);
			bio_pair_release(bp);
			return;
		}
	}

	/*
	 * If we find a matching packet in state WAITING or READ_WAIT, we can
	 * just append this bio to that packet.
	 */
	spin_lock(&pd->cdrw.active_list_lock);
	blocked_bio = 0;
	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
		if (pkt->sector == zone) {
			spin_lock(&pkt->lock);
			if ((pkt->state == PACKET_WAITING_STATE) ||
			    (pkt->state == PACKET_READ_WAIT_STATE)) {
				bio_list_add(&pkt->orig_bios, bio);
				pkt->write_size += bio->bi_size / CD_FRAMESIZE;
				if ((pkt->write_size >= pkt->frames) &&
				    (pkt->state == PACKET_WAITING_STATE)) {
					atomic_inc(&pkt->run_sm);
					wake_up(&pd->wqueue);
				}
				spin_unlock(&pkt->lock);
				spin_unlock(&pd->cdrw.active_list_lock);
				return;
			} else {
				blocked_bio = 1;
			}
			spin_unlock(&pkt->lock);
		}
	}
	spin_unlock(&pd->cdrw.active_list_lock);

 	/*
	 * Test if there is enough room left in the bio work queue
	 * (queue size >= congestion on mark).
	 * If not, wait till the work queue size is below the congestion off mark.
	 */
	spin_lock(&pd->lock);
	if (pd->write_congestion_on > 0
	    && pd->bio_queue_size >= pd->write_congestion_on) {
		set_bdi_congested(&q->backing_dev_info, BLK_RW_ASYNC);
		do {
			spin_unlock(&pd->lock);
			congestion_wait(BLK_RW_ASYNC, HZ);
			spin_lock(&pd->lock);
		} while(pd->bio_queue_size > pd->write_congestion_off);
	}
	spin_unlock(&pd->lock);

	/*
	 * No matching packet found. Store the bio in the work queue.
	 */
	node = mempool_alloc(pd->rb_pool, GFP_NOIO);
	node->bio = bio;
	spin_lock(&pd->lock);
	BUG_ON(pd->bio_queue_size < 0);
	was_empty = (pd->bio_queue_size == 0);
	pkt_rbtree_insert(pd, node);
	spin_unlock(&pd->lock);

	/*
	 * Wake up the worker thread.
	 */
	atomic_set(&pd->scan_queue, 1);
	if (was_empty) {
		/* This wake_up is required for correct operation */
		wake_up(&pd->wqueue);
	} else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
		/*
		 * This wake up is not required for correct operation,
		 * but improves performance in some cases.
		 */
		wake_up(&pd->wqueue);
	}
	return;
end_io:
	bio_io_error(bio);
}

static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
			  struct bio_vec *bvec)
{
	struct pktcdvd_device *pd = q->queuedata;
	sector_t zone = ZONE(bmd->bi_sector, pd);
	int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size;
	int remaining = (pd->settings.size << 9) - used;
	int remaining2;

	/*
	 * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
	 * boundary, pkt_make_request() will split the bio.
	 */
	remaining2 = PAGE_SIZE - bmd->bi_size;
	remaining = max(remaining, remaining2);

	BUG_ON(remaining < 0);
	return remaining;
}

static void pkt_init_queue(struct pktcdvd_device *pd)
{
	struct request_queue *q = pd->disk->queue;

	blk_queue_make_request(q, pkt_make_request);
	blk_queue_logical_block_size(q, CD_FRAMESIZE);
	blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
	blk_queue_merge_bvec(q, pkt_merge_bvec);
	q->queuedata = pd;
}

static int pkt_seq_show(struct seq_file *m, void *p)
{
	struct pktcdvd_device *pd = m->private;
	char *msg;
	char bdev_buf[BDEVNAME_SIZE];
	int states[PACKET_NUM_STATES];

	seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
		   bdevname(pd->bdev, bdev_buf));

	seq_printf(m, "\nSettings:\n");
	seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);

	if (pd->settings.write_type == 0)
		msg = "Packet";
	else
		msg = "Unknown";
	seq_printf(m, "\twrite type:\t\t%s\n", msg);

	seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
	seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);

	seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);

	if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
		msg = "Mode 1";
	else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
		msg = "Mode 2";
	else
		msg = "Unknown";
	seq_printf(m, "\tblock mode:\t\t%s\n", msg);

	seq_printf(m, "\nStatistics:\n");
	seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
	seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
	seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
	seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
	seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);

	seq_printf(m, "\nMisc:\n");
	seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
	seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
	seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
	seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
	seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
	seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);

	seq_printf(m, "\nQueue state:\n");
	seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
	seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
	seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);

	pkt_count_states(pd, states);
	seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
		   states[0], states[1], states[2], states[3], states[4], states[5]);

	seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
			pd->write_congestion_off,
			pd->write_congestion_on);
	return 0;
}

static int pkt_seq_open(struct inode *inode, struct file *file)
{
	return single_open(file, pkt_seq_show, PDE_DATA(inode));
}

static const struct file_operations pkt_proc_fops = {
	.open	= pkt_seq_open,
	.read	= seq_read,
	.llseek	= seq_lseek,
	.release = single_release
};

static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
{
	int i;
	int ret = 0;
	char b[BDEVNAME_SIZE];
	struct block_device *bdev;

	if (pd->pkt_dev == dev) {
		printk(DRIVER_NAME": Recursive setup not allowed\n");
		return -EBUSY;
	}
	for (i = 0; i < MAX_WRITERS; i++) {
		struct pktcdvd_device *pd2 = pkt_devs[i];
		if (!pd2)
			continue;
		if (pd2->bdev->bd_dev == dev) {
			printk(DRIVER_NAME": %s already setup\n", bdevname(pd2->bdev, b));
			return -EBUSY;
		}
		if (pd2->pkt_dev == dev) {
			printk(DRIVER_NAME": Can't chain pktcdvd devices\n");
			return -EBUSY;
		}
	}

	bdev = bdget(dev);
	if (!bdev)
		return -ENOMEM;
	ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL);
	if (ret)
		return ret;

	/* This is safe, since we have a reference from open(). */
	__module_get(THIS_MODULE);

	pd->bdev = bdev;
	set_blocksize(bdev, CD_FRAMESIZE);

	pkt_init_queue(pd);

	atomic_set(&pd->cdrw.pending_bios, 0);
	pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
	if (IS_ERR(pd->cdrw.thread)) {
		printk(DRIVER_NAME": can't start kernel thread\n");
		ret = -ENOMEM;
		goto out_mem;
	}

	proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd);
	DPRINTK(DRIVER_NAME": writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
	return 0;

out_mem:
	blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
	/* This is safe: open() is still holding a reference. */
	module_put(THIS_MODULE);
	return ret;
}

static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
{
	struct pktcdvd_device *pd = bdev->bd_disk->private_data;
	int ret;

	VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd,
		MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));

	mutex_lock(&pktcdvd_mutex);
	switch (cmd) {
	case CDROMEJECT:
		/*
		 * The door gets locked when the device is opened, so we
		 * have to unlock it or else the eject command fails.
		 */
		if (pd->refcnt == 1)
			pkt_lock_door(pd, 0);
		/* fallthru */
	/*
	 * forward selected CDROM ioctls to CD-ROM, for UDF
	 */
	case CDROMMULTISESSION:
	case CDROMREADTOCENTRY:
	case CDROM_LAST_WRITTEN:
	case CDROM_SEND_PACKET:
	case SCSI_IOCTL_SEND_COMMAND:
		ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
		break;

	default:
		VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
		ret = -ENOTTY;
	}
	mutex_unlock(&pktcdvd_mutex);

	return ret;
}

static unsigned int pkt_check_events(struct gendisk *disk,
				     unsigned int clearing)
{
	struct pktcdvd_device *pd = disk->private_data;
	struct gendisk *attached_disk;

	if (!pd)
		return 0;
	if (!pd->bdev)
		return 0;
	attached_disk = pd->bdev->bd_disk;
	if (!attached_disk || !attached_disk->fops->check_events)
		return 0;
	return attached_disk->fops->check_events(attached_disk, clearing);
}

static const struct block_device_operations pktcdvd_ops = {
	.owner =		THIS_MODULE,
	.open =			pkt_open,
	.release =		pkt_close,
	.ioctl =		pkt_ioctl,
	.check_events =		pkt_check_events,
};

static char *pktcdvd_devnode(struct gendisk *gd, umode_t *mode)
{
	return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
}

/*
 * Set up mapping from pktcdvd device to CD-ROM device.
 */
static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
{
	int idx;
	int ret = -ENOMEM;
	struct pktcdvd_device *pd;
	struct gendisk *disk;

	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);

	for (idx = 0; idx < MAX_WRITERS; idx++)
		if (!pkt_devs[idx])
			break;
	if (idx == MAX_WRITERS) {
		printk(DRIVER_NAME": max %d writers supported\n", MAX_WRITERS);
		ret = -EBUSY;
		goto out_mutex;
	}

	pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
	if (!pd)
		goto out_mutex;

	pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
						  sizeof(struct pkt_rb_node));
	if (!pd->rb_pool)
		goto out_mem;

	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
	INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
	spin_lock_init(&pd->cdrw.active_list_lock);

	spin_lock_init(&pd->lock);
	spin_lock_init(&pd->iosched.lock);
	bio_list_init(&pd->iosched.read_queue);
	bio_list_init(&pd->iosched.write_queue);
	sprintf(pd->name, DRIVER_NAME"%d", idx);
	init_waitqueue_head(&pd->wqueue);
	pd->bio_queue = RB_ROOT;

	pd->write_congestion_on  = write_congestion_on;
	pd->write_congestion_off = write_congestion_off;

	disk = alloc_disk(1);
	if (!disk)
		goto out_mem;
	pd->disk = disk;
	disk->major = pktdev_major;
	disk->first_minor = idx;
	disk->fops = &pktcdvd_ops;
	disk->flags = GENHD_FL_REMOVABLE;
	strcpy(disk->disk_name, pd->name);
	disk->devnode = pktcdvd_devnode;
	disk->private_data = pd;
	disk->queue = blk_alloc_queue(GFP_KERNEL);
	if (!disk->queue)
		goto out_mem2;

	pd->pkt_dev = MKDEV(pktdev_major, idx);
	ret = pkt_new_dev(pd, dev);
	if (ret)
		goto out_new_dev;

	/* inherit events of the host device */
	disk->events = pd->bdev->bd_disk->events;
	disk->async_events = pd->bdev->bd_disk->async_events;

	add_disk(disk);

	pkt_sysfs_dev_new(pd);
	pkt_debugfs_dev_new(pd);

	pkt_devs[idx] = pd;
	if (pkt_dev)
		*pkt_dev = pd->pkt_dev;

	mutex_unlock(&ctl_mutex);
	return 0;

out_new_dev:
	blk_cleanup_queue(disk->queue);
out_mem2:
	put_disk(disk);
out_mem:
	if (pd->rb_pool)
		mempool_destroy(pd->rb_pool);
	kfree(pd);
out_mutex:
	mutex_unlock(&ctl_mutex);
	printk(DRIVER_NAME": setup of pktcdvd device failed\n");
	return ret;
}

/*
 * Tear down mapping from pktcdvd device to CD-ROM device.
 */
static int pkt_remove_dev(dev_t pkt_dev)
{
	struct pktcdvd_device *pd;
	int idx;
	int ret = 0;

	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);

	for (idx = 0; idx < MAX_WRITERS; idx++) {
		pd = pkt_devs[idx];
		if (pd && (pd->pkt_dev == pkt_dev))
			break;
	}
	if (idx == MAX_WRITERS) {
		DPRINTK(DRIVER_NAME": dev not setup\n");
		ret = -ENXIO;
		goto out;
	}

	if (pd->refcnt > 0) {
		ret = -EBUSY;
		goto out;
	}
	if (!IS_ERR(pd->cdrw.thread))
		kthread_stop(pd->cdrw.thread);

	pkt_devs[idx] = NULL;

	pkt_debugfs_dev_remove(pd);
	pkt_sysfs_dev_remove(pd);

	blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);

	remove_proc_entry(pd->name, pkt_proc);
	DPRINTK(DRIVER_NAME": writer %s unmapped\n", pd->name);

	del_gendisk(pd->disk);
	blk_cleanup_queue(pd->disk->queue);
	put_disk(pd->disk);

	mempool_destroy(pd->rb_pool);
	kfree(pd);

	/* This is safe: open() is still holding a reference. */
	module_put(THIS_MODULE);

out:
	mutex_unlock(&ctl_mutex);
	return ret;
}

static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
{
	struct pktcdvd_device *pd;

	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);

	pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
	if (pd) {
		ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
		ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
	} else {
		ctrl_cmd->dev = 0;
		ctrl_cmd->pkt_dev = 0;
	}
	ctrl_cmd->num_devices = MAX_WRITERS;

	mutex_unlock(&ctl_mutex);
}

static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	struct pkt_ctrl_command ctrl_cmd;
	int ret = 0;
	dev_t pkt_dev = 0;

	if (cmd != PACKET_CTRL_CMD)
		return -ENOTTY;

	if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
		return -EFAULT;

	switch (ctrl_cmd.command) {
	case PKT_CTRL_CMD_SETUP:
		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;
		ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
		ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
		break;
	case PKT_CTRL_CMD_TEARDOWN:
		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;
		ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
		break;
	case PKT_CTRL_CMD_STATUS:
		pkt_get_status(&ctrl_cmd);
		break;
	default:
		return -ENOTTY;
	}

	if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
		return -EFAULT;
	return ret;
}

#ifdef CONFIG_COMPAT
static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
}
#endif

static const struct file_operations pkt_ctl_fops = {
	.open		= nonseekable_open,
	.unlocked_ioctl	= pkt_ctl_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl	= pkt_ctl_compat_ioctl,
#endif
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
};

static struct miscdevice pkt_misc = {
	.minor 		= MISC_DYNAMIC_MINOR,
	.name  		= DRIVER_NAME,
	.nodename	= "pktcdvd/control",
	.fops  		= &pkt_ctl_fops
};

static int __init pkt_init(void)
{
	int ret;

	mutex_init(&ctl_mutex);

	psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
					sizeof(struct packet_stacked_data));
	if (!psd_pool)
		return -ENOMEM;

	ret = register_blkdev(pktdev_major, DRIVER_NAME);
	if (ret < 0) {
		printk(DRIVER_NAME": Unable to register block device\n");
		goto out2;
	}
	if (!pktdev_major)
		pktdev_major = ret;

	ret = pkt_sysfs_init();
	if (ret)
		goto out;

	pkt_debugfs_init();

	ret = misc_register(&pkt_misc);
	if (ret) {
		printk(DRIVER_NAME": Unable to register misc device\n");
		goto out_misc;
	}

	pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);

	return 0;

out_misc:
	pkt_debugfs_cleanup();
	pkt_sysfs_cleanup();
out:
	unregister_blkdev(pktdev_major, DRIVER_NAME);
out2:
	mempool_destroy(psd_pool);
	return ret;
}

static void __exit pkt_exit(void)
{
	remove_proc_entry("driver/"DRIVER_NAME, NULL);
	misc_deregister(&pkt_misc);

	pkt_debugfs_cleanup();
	pkt_sysfs_cleanup();

	unregister_blkdev(pktdev_major, DRIVER_NAME);
	mempool_destroy(psd_pool);
}

MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
MODULE_LICENSE("GPL");

module_init(pkt_init);
module_exit(pkt_exit);


text:
/*
$('.comment-list li').hover(
	function (){
		cid = $(this).data('commentId');
		$('#button-div-'+cid).css("visibility","visible");
	},
	function (){
		cid = $(this).data('commentId');
		if ($("#button-div-"+cid+" form").length==0){
			$('#button-div-'+cid).css("visibility","hidden");
		}

	}
);
*/
$('#id_a_hide').click(function (event) {
	show_comment_a();
});

$('#id_close_btn').click(function (event) {
	jQuery.fancybox.close();
	if ($('#id_close_btn').data('commentsChanged') == 'yes') {
		controller.postRequest('/jurisdiction/{{jurisdiction.id}}/',{ajax: 'reload_all_items'});
	}
});
$('.modal_dialog_close').click(function (event) {
	jQuery.fancybox.close();
	if ($('#id_close_btn').data('commentsChanged') == 'yes') {
		controller.postRequest('/jurisdiction/{{jurisdiction.id}}/',{ajax: 'reload_all_items'});
	}
});

function show_comment_a(){
	$('#show_commnet_div').empty().append(' Show old comments ');
	$('#old_list').hide();
	$('#id_a_show').bind('click', function(){hide_comment_a();});
}

function hide_comment_a(){
	$('#show_commnet_div').empty().append(' Hide old comments ');
	$('#old_list').show();
	$('#id_a_hide').bind('click', function(){show_comment_a();});;
}

$('#add_new_comment_bt').click(function (){
	controller.postRequest('/jurisdiction_comment/',{ajax: 'create_jurisdiction_comment', jurisdiction_id: {{jurisdiction.id}}, answer_id: {{answer_id}} });
	return false;
});

$('#show_old_comments_link').click(function() {
	jid = $(this).data('jid')
	old_id = $(this).data('oldid')
	controller.postRequest('/jurisdiction_comment/',{ajax: 'show_old_comments', jurisdiction_id: jid, answer_id: old_id });
	return false;
});

redpajama_set_name: RedPajamaGithub


text:
use strict;
use Data::Dumper;
use File::Copy;
use Getopt::Long;
use XML::LibXML;
use String::CamelCase 'decamelize';

#
# This is a SAS Component
#

=head1 NAME

ermodel_to_text

=head1 SYNOPSIS

ermodel_to_text [--decamelize] > output

=head1 DESCRIPTION

Given the XML description of an Entity-Relationship model on stdin, dump the description
of the model as an easy-to-parse tab-delimited text file.

=head1 COMMAND-LINE OPTIONS

Usage: ermodel_to_text [--decamelize] > output

    --decamelize

        If set, convert all entity, relationship, and field names to a decamelized form.

=head1 OUTPUT FORMAT

The output is a tab-delimited file. It contains blocks of data delimited by
lines containing only the string "//".

Each block of data describes either an entity or a relationship. A single line
defines the entity or relationship name and the associated metadata. The
remaining lines in the block define the field data associated with the entity or relationship.

An entity line contains the following fields:

=over 4

=item The string "entity"

=item The entity name

=back

A relationship line contains the following fields:

=over 4

=item The string "relationship"

=item The relationship name

=item The name of the "from" entity.

=item The name of the "to" entity.

=item The arity of the relationship (1M or MM).

=item The name of the converse relationship.

=back

Each field description line contains the following fields:

=over 4

=item The name of the field

=item The field type

=item The name of a relation, if the field data is stored in a separate relation.

=back

=head1 AUTHORS

L<The SEED Project|http://www.theseed.org>

=cut

my $decamelize;

my $rc = GetOptions("decamelize" => \$decamelize);

$rc && @ARGV == 0 or die "Usage: $0 [--decamelize] < DBD-xml-file > tab-sep-output\n";

my $doc = XML::LibXML->new->parse_fh(\*STDIN);
$doc or die "Cannot parse XML data\n";

my %etypes;

for my $e ($doc->findnodes('//Entities/Entity'))
{
    my $name = $e->getAttribute("name");
    my $name_conv = convert_name($name);

    my $keytype = $e->getAttribute("keyType");
    $etypes{$name} = $keytype;

    print join("\t", "entity", $name_conv), "\n";
    print join("\t", 'id', $keytype, ''), "\n";
    for my $fn ($e->findnodes('Fields/Field'))
    {
	my $fname = $fn->getAttribute("name");
	my $fname_conv = convert_field_name($fname);
	my $ftype = $fn->getAttribute("type");
	my $rel = $fn->getAttribute("relation");
	print join("\t", $fname_conv, $ftype, $rel), "\n";
    }
    print "//\n";
}

for my $r ($doc->findnodes('//Relationships/Relationship'))
{
    my $name = $r->getAttribute("name");
    my $name_conv = convert_name($name);

    my $from = $r->getAttribute("from");
    my $from_conv = convert_name($from);
    my $from_type = $etypes{$from};

    my $to = $r->getAttribute("to");
    my $to_conv = convert_name($to);
    my $to_type = $etypes{$to};

    my $arity = $r->getAttribute("arity");
    my $converse = $r->getAttribute("converse");
    my $converse_conv = convert_name($converse);

    print join("\t", "relationship", $name_conv, $from_conv, $to_conv, $arity, $converse_conv), "\n";

    print join("\t", 'from_link', $from_type, ''), "\n";
    print join("\t", 'to_link', $to_type, ''), "\n";

    for my $fn ($r->findnodes('Fields/Field'))
    {
	my $fname = $fn->getAttribute("name");
	my $fname_conv = convert_field_name($fname);
	my $ftype = $fn->getAttribute("type");
	my $rel = $fn->getAttribute("relation");
	print join("\t", $fname_conv, $ftype, $rel), "\n";
    }
    print "//\n";
}

sub convert_name
{
    my($n) = @_;
    if ($decamelize)
    {
	return decamelize($n);
    }
    else
    {
	return $n;
    }
}

sub convert_field_name
{
    my($n) = @_;
    $n =~ s/-/_/g;
    return $n;
}

__DATA__


text:
* [Homepage](https://github.com/maxmeyer/workplace-tables#readme)
* [Issues](https://github.com/maxmeyer/workplace-tables/issues)
* [Documentation](http://rubydoc.info/gems/workplace-tables/frames)
* [Email](mailto:dev at fedux.org)

## Description

TODO: Description

## Features

## Examples

    require 'workplace/tables'

## Requirements

## Install

    $ gem install workplace-tables

## Synopsis

    $ workplace-tables

## Copyright

Copyright (c) 2012 Max Meyer

See {file:LICENSE.txt} for details.


text:
<?xml version="1.0" encoding="UTF-8"?>
<GeocodeResponse>
 <status>OK</status>
 <result>
  <type>locality</type>
  <type>political</type>
  <formatted_address>3375 Krummnußbaum, Austria</formatted_address>
  <address_component>
   <long_name>Krummnußbaum</long_name>
   <short_name>Krummnußbaum</short_name>
   <type>locality</type>
   <type>political</type>
  </address_component>
  <address_component>
   <long_name>Gemeinde Krummnußbaum</long_name>
   <short_name>Gemeinde Krummnußbaum</short_name>
   <type>administrative_area_level_3</type>
   <type>political</type>
  </address_component>
  <address_component>
   <long_name>Melk District</long_name>
   <short_name>Melk District</short_name>
   <type>administrative_area_level_2</type>
   <type>political</type>
  </address_component>
  <address_component>
   <long_name>Lower Austria</long_name>
   <short_name>Lower Austria</short_name>
   <type>administrative_area_level_1</type>
   <type>political</type>
  </address_component>
  <address_component>
   <long_name>Austria</long_name>
   <short_name>AT</short_name>
   <type>country</type>
   <type>political</type>
  </address_component>
  <address_component>
   <long_name>3375</long_name>
   <short_name>3375</short_name>
   <type>postal_code</type>
  </address_component>
  <geometry>
   <location>
    <lat>48.2088640</lat>
    <lng>15.1639272</lng>
   </location>
   <location_type>APPROXIMATE</location_type>
   <viewport>
    <southwest>
     <lat>48.2014276</lat>
     <lng>15.1479198</lng>
    </southwest>
    <northeast>
     <lat>48.2162993</lat>
     <lng>15.1799346</lng>
    </northeast>
   </viewport>
  </geometry>
  <place_id>ChIJmy8hZEVdckcRILVR5oAbVeQ</place_id>
 </result>
</GeocodeResponse>


text:
using System;
using System.Collections.Generic;
using System.Linq;

namespace UnicodeNormalizationSample
{
    // 合成・分解共通の処理は Normalizer.cs へ
    partial class Normalizer
    {
        /// 合成テーブルを作成します。
        /// <param name="unicodeData">UnicodeData.txt の内容</param>
        /// <param name="normalizationProps">DerivedNormalizationProps.txt の内容</param>
        private static IReadOnlyDictionary<CodePointPair, uint> CreateCompositionTable(UnicodeDataRecord[] unicodeData, NormalizationProps normalizationProps)
        {
            var fullCompositionExclusion = new HashSet<uint>(normalizationProps.FullCompositionExclusion);
            return unicodeData.Where(x => x.DecompositionMapping != null
                    && x.DecompositionMapping.Type == null // 互換分解でない
                    && x.DecompositionMapping.Mapping.Length == 2 // 1文字の分解でない -> 2文字
                    && !fullCompositionExclusion.Contains(x.CodePoint) // Full_Composition_Exclusion
                ).ToDictionary(
                    x => new CodePointPair(x.DecompositionMapping.Mapping[0], x.DecompositionMapping.Mapping[1]),
                    x => x.CodePoint
                );
        }

        /// 正規合成を行います。
        /// <param name="input">UTF-32でエンコードされた文字列。</param>
        /// <param name="compatibility">互換分解するかどうか。</param>
        public uint[] Compose(uint[] input, bool compatibility)
        {
            var buffer = Decompose(input, compatibility);

            if (buffer.Length <= 1)
                return buffer;

            var lastStarter = default(uint);
            var lastStarterIndex = default(int);

            var inputIndex = 0;

            // 最初の starter を探す
            while (true)
            {
                var c = buffer[inputIndex];
                if (GetCanonicalCombiningClass(c) == 0)
                {
                    lastStarter = c;
                    lastStarterIndex = inputIndex++;
                    break;
                }

                if (++inputIndex >= buffer.Length)
                    return buffer; // 合成できないので終了
            }

            var insertIndex = inputIndex;
            var lastChar = lastStarter;
            var lastCcc = 0;

            for (; inputIndex < buffer.Length; inputIndex++)
            {
                var c = buffer[inputIndex];

                // ハングル
                var LIndex = lastChar - LBase;
                if (LIndex >= 0 && LIndex < LCount)
                {
                    var VIndex = c - VBase;
                    if (VIndex >= 0 && VIndex < VCount)
                    {
                        lastChar = SBase + (LIndex * VCount + VIndex) * TCount;
                        buffer[insertIndex - 1] = lastChar;
                        lastCcc = 0;
                        continue;
                    }
                }

                var SIndex = lastChar - SBase;
                if (SIndex >= 0 && SIndex < SCount && (SIndex % TCount) == 0)
                {
                    var TIndex = c - TBase;
                    if (0 < TIndex && TIndex < TCount)
                    {
                        lastChar += TIndex;
                        buffer[insertIndex - 1] = lastChar;
                        lastCcc = 0;
                        continue;
                    }
                }

                // ここから通常の合成
                var ccc = GetCanonicalCombiningClass(c);

                uint composed;
                if ((ccc == 0 ? lastCcc == 0 : lastCcc < ccc) // ブロック条件
                    && _compositionTable.TryGetValue(new CodePointPair(lastStarter, c), out composed))
                {
                    buffer[lastStarterIndex] = composed;
                    lastStarter = composed;
                }
                else
                {
                    if (ccc == 0)
                    {
                        lastStarter = c;
                        lastStarterIndex = insertIndex;
                    }
                    buffer[insertIndex++] = c;
                    lastChar = c;
                    lastCcc = ccc;
                }
            }

            Array.Resize(ref buffer, insertIndex);
            return buffer;
        }
    }
}


text:
include (CMakeParseArguments)
include ("cmake/tooling-cmake-util/PolysquareToolingUtil")

set (CLANG_TIDY_EXIT_STATUS_WRAPPER_LOCATION
     "${CMAKE_CURRENT_LIST_DIR}/util/ClangTidyExitStatusWrapper.cmake")
set (_CLANG_TIDY_LIST_DIR "${CMAKE_CURRENT_LIST_DIR}")

macro (clang_tidy_validate CONTINUE)

    if (NOT DEFINED CLANG_TIDY_FOUND)

        set (CMAKE_MODULE_PATH
             ${CMAKE_MODULE_PATH} # NOLINT:correctness/quotes
             "${_CLANG_TIDY_LIST_DIR}")
        find_package (CLANGTIDY ${ARGN})

    endif ()

    set (${CONTINUE} ${CLANG_TIDY_FOUND})

endmacro ()

set (CMAKE_EXPORT_COMPILE_COMMANDS TRUE)

function (clang_tidy_check_target_sources TARGET)

    set (CHECK_SOURCES_OPTIONS
         CHECK_GENERATED
         WARN_ONLY)
    set (CHECK_SOURCES_SINGLEVAR_OPTIONS
         FORCE_LANGUAGE)
    set (CHECK_SOURCES_MULTIVAR_OPTIONS
         ENABLE_CHECKS
         DISABLE_CHECKS
         INTERNAL_INCLUDE_DIRS
         EXTERNAL_INCLUDE_DIRS
         DEFINES
         CPP_IDENTIFIERS
         DEPENDS)

    cmake_parse_arguments (CHECK_SOURCES
                           "${CHECK_SOURCES_OPTIONS}"
                           "${CHECK_SOURCES_SINGLEVAR_OPTIONS}"
                           "${CHECK_SOURCES_MULTIVAR_OPTIONS}"
                           ${ARGN})

    list (APPEND CHECK_SOURCES_DISABLE_CHECKS
                 "clang-diagnostic-unknown-argument"
                 "clang-diagnostic-unused-command-line-argument")

    psq_strip_extraneous_sources (FILES_TO_CHECK ${TARGET})
    psq_handle_check_generated_option (CHECK_SOURCES FILES_TO_CHECK
                                       SOURCES ${FILES_TO_CHECK})

    string (REPLACE ";" "," ENABLE_CHECKS_LIST "${CHECK_SOURCES_ENABLE_CHECKS}")
    string (REPLACE ";" "," DISABLE_CHECKS_LIST
            "${CHECK_SOURCES_DISABLE_CHECKS}")

    set (CLANG_TIDY_OPTIONS
         -DVERBOSE=${CMAKE_VERBOSE_MAKEFILE}
         "-DCLANG_TIDY_EXECUTABLE=${CLANG_TIDY_EXECUTABLE}"
         -DENABLE_CHECKS=${ENABLE_CHECKS_LIST}
         -DDISABLE_CHECKS=${DISABLE_CHECKS_LIST})

    psq_add_switch (CLANG_TIDY_OPTIONS CHECK_SOURCES_WARN_ONLY
                    ON -DWARN_ONLY=ON
                    OFF -DWARN_ONLY=OFF)

    # Scan each source file to determine its language. We might need
    # it later when generating a compilation database.
    if (CHECK_SOURCES_FORCE_LANGUAGE)

        set (FORCE_LANGUAGE_OPTION
             FORCE_LANGUAGE ${CHECK_SOURCES_FORCE_LANGUAGE})

    endif ()

    # Scan source languages and sort them out now. We will pass
    # each of these lists to psq_make_compilation_db for later
    # use.
    psq_forward_options (CHECK_SOURCES SORT_TO_LANGS_FORWARD_OPTIONS
                         SINGLEVAR_ARGS FORCE_LANGUAGE
                         MULTIVAR_ARGS CPP_IDENTIFIERS)
    psq_sort_sources_to_languages (C_SOURCES CXX_SOURCES HEADERS
                                   SOURCES ${FILES_TO_CHECK}
                                   ${SORT_TO_LANGS_FORWARD_OPTIONS}
                                   INCLUDES
                                   ${CHECK_SOURCES_INTERNAL_INCLUDE_DIRS})

    # By default, fall back to using generated compilation database
    # until it can be proven that using the CMake generated one is a better
    # choice.
    set (CUSTOM_COMPILATION_DB_SOURCES ${FILES_TO_CHECK})

    if (CMAKE_GENERATOR STREQUAL "Ninja" OR
        CMAKE_GENERATOR STREQUAL "Unix Makefiles")

        psq_get_target_command_attach_point (${TARGET} WHEN)

        # A compilation database is generated for all linkable targets, so
        # if we're running PRE_LINK then use that
        if (WHEN STREQUAL "PRE_LINK")

            set (CUSTOM_COMPILATION_DB_SOURCES ${HEADERS})

        endif ()

    endif (CMAKE_GENERATOR STREQUAL "Ninja" OR
           CMAKE_GENERATOR STREQUAL "Unix Makefiles")

    # Keep C_SOURCES and CXX_SOURCES intersecting with the sources
    # we wish to make a compilation DB for.
    psq_get_list_intersection (C_COMP_DB_SOURCES
                               SOURCE ${C_SOURCES}
                               INTERSECTION ${CUSTOM_COMPILATION_DB_SOURCES})
    psq_get_list_intersection (CXX_COMP_DB_SOURCES
                               SOURCE ${CXX_SOURCES}
                               INTERSECTION ${CUSTOM_COMPILATION_DB_SOURCES})

    # For mixed source-header targets or UTILITY targets, we need
    # to generate a fake compilation database as CMake won't do it
    # for us in this instance.
    psq_make_compilation_db (${TARGET}
                             CUSTOM_COMPILATION_DB_DIR
                             ${FORCE_LANGUAGE_OPTION}
                             C_SOURCES ${C_COMP_DB_SOURCES}
                             CXX_SOURCES ${CXX_COMP_DB_SOURCES}
                             INTERNAL_INCLUDE_DIRS
                             ${CHECK_SOURCES_INTERNAL_INCLUDE_DIRS}
                             EXTERNAL_INCLUDE_DIRS
                             ${CHECK_SOURCES_EXTERNAL_INCLUDE_DIRS}
                             DEFINES
                             ${CHECK_SOURCES_DEFINES})

    foreach (SOURCE ${FILES_TO_CHECK})

        # Check if this source is one that requires a custom
        # compilation database
        list (FIND CUSTOM_COMPILATION_DB_SOURCES "${SOURCE}" SOURCE_INDEX)

        if (NOT SOURCE_INDEX EQUAL -1)

            set (SOURCE_COMP_DB "${CUSTOM_COMPILATION_DB_DIR}")

        else ()

            set (SOURCE_COMP_DB "${CMAKE_BINARY_DIR}")

        endif ()

        psq_forward_options (CHECK_SOURCES RUN_TOOL_ON_SOURCE_FORWARD
                             MULTIVAR_ARGS DEPENDS)
        psq_run_tool_on_source (${TARGET} "${SOURCE}" "clang-tidy"
                                COMMAND
                                "${CMAKE_COMMAND}"
                                "-DSOURCE=${SOURCE}"
                                -DCUSTOM_COMPILATION_DB_DIR=${SOURCE_COMP_DB}
                                ${CLANG_TIDY_OPTIONS}
                                -P
                                ${CLANG_TIDY_EXIT_STATUS_WRAPPER_LOCATION}
                                ${RUN_TOOL_ON_SOURCE_FORWARD})
    endforeach ()

endfunction ()