pktcdvd.c 72.7 KB
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/*
 * Copyright (C) 2000 Jens Axboe <axboe@suse.de>
 * Copyright (C) 2001-2004 Peter Osterlund <petero2@telia.com>
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 * Copyright (C) 2006 Thomas Maier <balagi@justmail.de>
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 *
 * May be copied or modified under the terms of the GNU General Public
 * License.  See linux/COPYING for more information.
 *
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 * Packet writing layer for ATAPI and SCSI CD-RW, DVD+RW, DVD-RW and
 * DVD-RAM devices.
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 *
 * Theory of operation:
 *
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 * At the lowest level, there is the standard driver for the CD/DVD device,
 * typically ide-cd.c or sr.c. This driver can handle read and write requests,
 * but it doesn't know anything about the special restrictions that apply to
 * packet writing. One restriction is that write requests must be aligned to
 * packet boundaries on the physical media, and the size of a write request
 * must be equal to the packet size. Another restriction is that a
 * GPCMD_FLUSH_CACHE command has to be issued to the drive before a read
 * command, if the previous command was a write.
 *
 * The purpose of the packet writing driver is to hide these restrictions from
 * higher layers, such as file systems, and present a block device that can be
 * randomly read and written using 2kB-sized blocks.
 *
 * The lowest layer in the packet writing driver is the packet I/O scheduler.
 * Its data is defined by the struct packet_iosched and includes two bio
 * queues with pending read and write requests. These queues are processed
 * by the pkt_iosched_process_queue() function. The write requests in this
 * queue are already properly aligned and sized. This layer is responsible for
 * issuing the flush cache commands and scheduling the I/O in a good order.
 *
 * The next layer transforms unaligned write requests to aligned writes. This
 * transformation requires reading missing pieces of data from the underlying
 * block device, assembling the pieces to full packets and queuing them to the
 * packet I/O scheduler.
 *
 * At the top layer there is a custom make_request_fn function that forwards
 * read requests directly to the iosched queue and puts write requests in the
 * unaligned write queue. A kernel thread performs the necessary read
 * gathering to convert the unaligned writes to aligned writes and then feeds
 * them to the packet I/O scheduler.
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 *
 *************************************************************************/

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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

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#include <linux/pktcdvd.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
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#include <linux/compat.h>
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#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>
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#include <linux/freezer.h>
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#include <linux/mutex.h>
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#include <linux/slab.h>
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#include <linux/backing-dev.h>
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#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_ioctl.h>
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#include <scsi/scsi.h>
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#include <linux/debugfs.h>
#include <linux/device.h>
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#include <linux/uaccess.h>
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#define DRIVER_NAME	"pktcdvd"

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#define pkt_err(pd, fmt, ...)						\
	pr_err("%s: " fmt, pd->name, ##__VA_ARGS__)
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#define pkt_notice(pd, fmt, ...)					\
	pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__)
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#define pkt_info(pd, fmt, ...)						\
	pr_info("%s: " fmt, pd->name, ##__VA_ARGS__)
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#define pkt_dbg(level, pd, fmt, ...)					\
do {									\
	if (level == 2 && PACKET_DEBUG >= 2)				\
		pr_notice("%s: %s():" fmt,				\
			  pd->name, __func__, ##__VA_ARGS__);		\
	else if (level == 1 && PACKET_DEBUG >= 1)			\
		pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__);		\
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} while (0)
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#define MAX_SPEED 0xffff

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static DEFINE_MUTEX(pktcdvd_mutex);
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static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
static struct proc_dir_entry *pkt_proc;
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static int pktdev_major;
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static int write_congestion_on  = PKT_WRITE_CONGESTION_ON;
static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
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static struct mutex ctl_mutex;	/* Serialize open/close/setup/teardown */
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static mempool_t *psd_pool;
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static struct bio_set *pkt_bio_set;
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static struct class	*class_pktcdvd = NULL;    /* /sys/class/pktcdvd */
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static struct dentry	*pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
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/* 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);

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static sector_t get_zone(sector_t sector, struct pktcdvd_device *pd)
{
	return (sector + pd->offset) & ~(sector_t)(pd->settings.size - 1);
}
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/*
 * 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;
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	int error;

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	p = kzalloc(sizeof(*p), GFP_KERNEL);
	if (!p)
		return NULL;
	p->pd = pd;
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	error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
	if (error) {
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		kobject_put(&p->kobj);
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		return NULL;
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	}
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	kobject_uevent(&p->kobj, KOBJ_ADD);
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	return p;
}
/*
 * remove a pktcdvd kernel object.
 */
static void pkt_kobj_remove(struct pktcdvd_kobj *p)
{
	if (p)
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		kobject_put(&p->kobj);
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}
/*
 * 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) \
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	static struct attribute _obj = { .name = _name, .mode = _mode }
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/**********************************************************
  /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;

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	if (strcmp(attr->name, "reset") == 0 && len > 0) {
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		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
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		   && sscanf(data, "%d", &val) == 1) {
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		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
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		   && sscanf(data, "%d", &val) == 1) {
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		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;
}

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static const struct sysfs_ops kobj_pkt_ops = {
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	.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) {
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		pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
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					"%s", pd->name);
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		if (IS_ERR(pd->dev))
			pd->dev = NULL;
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	}
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	if (pd->dev) {
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		pd->kobj_stat = pkt_kobj_create(pd, "stat",
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					&pd->dev->kobj,
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					&kobj_pkt_type_stat);
		pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
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					&pd->dev->kobj,
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					&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)
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		device_unregister(pd->dev);
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}


/********************************************************************
  /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);
}
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static ssize_t device_map_show(struct class *c, struct class_attribute *attr,
			       char *data)
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{
	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;
}
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static CLASS_ATTR_RO(device_map);
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static ssize_t add_store(struct class *c, struct class_attribute *attr,
			 const char *buf, size_t count)
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{
	unsigned int major, minor;
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	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
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		/* pkt_setup_dev() expects caller to hold reference to self */
		if (!try_module_get(THIS_MODULE))
			return -ENODEV;

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

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		return count;
	}
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	return -EINVAL;
}
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static CLASS_ATTR_WO(add);
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static ssize_t remove_store(struct class *c, struct class_attribute *attr,
			    const char *buf, size_t count)
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{
	unsigned int major, minor;
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	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
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		pkt_remove_dev(MKDEV(major, minor));
		return count;
	}
	return -EINVAL;
}
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static CLASS_ATTR_WO(remove);
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static struct attribute *class_pktcdvd_attrs[] = {
	&class_attr_add.attr,
	&class_attr_remove.attr,
	&class_attr_device_map.attr,
	NULL,
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};
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ATTRIBUTE_GROUPS(class_pktcdvd);
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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;
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	class_pktcdvd->class_groups = class_pktcdvd_groups;
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	ret = class_register(class_pktcdvd);
	if (ret) {
		kfree(class_pktcdvd);
		class_pktcdvd = NULL;
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		pr_err("failed to create class pktcdvd\n");
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		return ret;
	}
	return 0;
}

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

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

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  /sys/kernel/debug/pktcdvd[0-7]/
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			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);
}

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static const struct file_operations debug_fops = {
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	.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_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
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	if (!pd->dfs_d_root)
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		return;
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	pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
				pd->dfs_d_root, pd, &debug_fops);
}

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

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

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

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

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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)) {
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		pkt_dbg(2, pd, "queue empty\n");
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		atomic_set(&pd->iosched.attention, 1);
		wake_up(&pd->wqueue);
	}
}

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

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

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

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

	spin_lock_init(&pkt->lock);
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	bio_list_init(&pkt->orig_bios);
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	for (i = 0; i < frames; i++) {
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		struct bio *bio = bio_kmalloc(GFP_KERNEL, 1);
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		if (!bio)
			goto no_rd_bio;
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		pkt->r_bios[i] = bio;
	}

	return pkt;

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

no_page:
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	for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
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		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;

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	for (i = 0; i < pkt->frames; i++) {
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		struct bio *bio = pkt->r_bios[i];
		if (bio)
			bio_put(bio);
	}
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	for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
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		__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);
	}
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	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
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}

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

607 608
	BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));

L
Linus Torvalds 已提交
609
	while (nr_packets > 0) {
610
		pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
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611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630
		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);
}

631
static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
L
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{
	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);
655
		if (s <= tmp->bio->bi_iter.bi_sector)
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			next = n->rb_left;
		else
			next = n->rb_right;
		if (!next)
			break;
		n = next;
	}

664
	if (s > tmp->bio->bi_iter.bi_sector) {
L
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665 666 667 668
		tmp = pkt_rbtree_next(tmp);
		if (!tmp)
			return NULL;
	}
669
	BUG_ON(s > tmp->bio->bi_iter.bi_sector);
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	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;
680
	sector_t s = node->bio->bi_iter.bi_sector;
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	struct pkt_rb_node *tmp;

	while (*p) {
		parent = *p;
		tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
686
		if (s < tmp->bio->bi_iter.bi_sector)
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			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)
{
702
	struct request_queue *q = bdev_get_queue(pd->bdev);
L
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703
	struct request *rq;
704 705 706
	int ret = 0;

	rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
707
			     REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, __GFP_RECLAIM);
708 709
	if (IS_ERR(rq))
		return PTR_ERR(rq);
710 711

	if (cgc->buflen) {
J
Julia Lawall 已提交
712
		ret = blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen,
713
				      __GFP_RECLAIM);
J
Julia Lawall 已提交
714
		if (ret)
715 716
			goto out;
	}
L
Linus Torvalds 已提交
717

718 719
	scsi_req(rq)->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
	memcpy(scsi_req(rq)->cmd, cgc->cmd, CDROM_PACKET_SIZE);
L
Linus Torvalds 已提交
720 721 722

	rq->timeout = 60*HZ;
	if (cgc->quiet)
723
		rq->rq_flags |= RQF_QUIET;
L
Linus Torvalds 已提交
724

725
	blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
726
	if (scsi_req(rq)->result)
A
Andrew Morton 已提交
727
		ret = -EIO;
728
out:
L
Linus Torvalds 已提交
729
	blk_put_request(rq);
730
	return ret;
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}

733 734 735 736 737 738 739 740 741 742 743
static const char *sense_key_string(__u8 index)
{
	static const char * const info[] = {
		"No sense", "Recovered error", "Not ready",
		"Medium error", "Hardware error", "Illegal request",
		"Unit attention", "Data protect", "Blank check",
	};

	return index < ARRAY_SIZE(info) ? info[index] : "INVALID";
}

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/*
 * A generic sense dump / resolve mechanism should be implemented across
 * all ATAPI + SCSI devices.
 */
748 749
static void pkt_dump_sense(struct pktcdvd_device *pd,
			   struct packet_command *cgc)
L
Linus Torvalds 已提交
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{
	struct request_sense *sense = cgc->sense;

753
	if (sense)
754 755 756 757
		pkt_err(pd, "%*ph - sense %02x.%02x.%02x (%s)\n",
			CDROM_PACKET_SIZE, cgc->cmd,
			sense->sense_key, sense->asc, sense->ascq,
			sense_key_string(sense->sense_key));
758
	else
759
		pkt_err(pd, "%*ph - no sense\n", CDROM_PACKET_SIZE, cgc->cmd);
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}

/*
 * 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
 */
786 787
static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
				unsigned write_speed, unsigned read_speed)
L
Linus Torvalds 已提交
788 789 790 791 792 793 794 795 796 797 798 799 800 801
{
	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)))
802
		pkt_dump_sense(pd, &cgc);
L
Linus Torvalds 已提交
803 804 805 806 807 808 809 810

	return ret;
}

/*
 * Queue a bio for processing by the low-level CD device. Must be called
 * from process context.
 */
811
static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
L
Linus Torvalds 已提交
812 813
{
	spin_lock(&pd->iosched.lock);
814 815 816 817
	if (bio_data_dir(bio) == READ)
		bio_list_add(&pd->iosched.read_queue, bio);
	else
		bio_list_add(&pd->iosched.write_queue, bio);
L
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818 819 820 821 822 823 824 825 826 827 828
	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.
829
 * - Switching between reading and writing is slow, so don't do it more often
L
Linus Torvalds 已提交
830
 *   than necessary.
831 832 833 834
 * - 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.
L
Linus Torvalds 已提交
835 836 837 838 839 840 841 842 843 844 845 846 847 848
 * - 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;
849
		int reads_queued, writes_queued;
L
Linus Torvalds 已提交
850 851

		spin_lock(&pd->iosched.lock);
852 853
		reads_queued = !bio_list_empty(&pd->iosched.read_queue);
		writes_queued = !bio_list_empty(&pd->iosched.write_queue);
L
Linus Torvalds 已提交
854 855 856 857 858 859
		spin_unlock(&pd->iosched.lock);

		if (!reads_queued && !writes_queued)
			break;

		if (pd->iosched.writing) {
860 861
			int need_write_seek = 1;
			spin_lock(&pd->iosched.lock);
862
			bio = bio_list_peek(&pd->iosched.write_queue);
863
			spin_unlock(&pd->iosched.lock);
864 865
			if (bio && (bio->bi_iter.bi_sector ==
				    pd->iosched.last_write))
866 867
				need_write_seek = 0;
			if (need_write_seek && reads_queued) {
L
Linus Torvalds 已提交
868
				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
869
					pkt_dbg(2, pd, "write, waiting\n");
L
Linus Torvalds 已提交
870 871 872 873 874 875 876 877
					break;
				}
				pkt_flush_cache(pd);
				pd->iosched.writing = 0;
			}
		} else {
			if (!reads_queued && writes_queued) {
				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
878
					pkt_dbg(2, pd, "read, waiting\n");
L
Linus Torvalds 已提交
879 880 881 882 883 884 885
					break;
				}
				pd->iosched.writing = 1;
			}
		}

		spin_lock(&pd->iosched.lock);
886 887 888 889
		if (pd->iosched.writing)
			bio = bio_list_pop(&pd->iosched.write_queue);
		else
			bio = bio_list_pop(&pd->iosched.read_queue);
L
Linus Torvalds 已提交
890 891 892 893 894 895
		spin_unlock(&pd->iosched.lock);

		if (!bio)
			continue;

		if (bio_data_dir(bio) == READ)
896 897
			pd->iosched.successive_reads +=
				bio->bi_iter.bi_size >> 10;
898
		else {
L
Linus Torvalds 已提交
899
			pd->iosched.successive_reads = 0;
K
Kent Overstreet 已提交
900
			pd->iosched.last_write = bio_end_sector(bio);
901
		}
L
Linus Torvalds 已提交
902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922
		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.
 */
923
static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
L
Linus Torvalds 已提交
924
{
925
	if ((pd->settings.size << 9) / CD_FRAMESIZE
926
	    <= queue_max_segments(q)) {
L
Linus Torvalds 已提交
927 928 929 930 931
		/*
		 * The cdrom device can handle one segment/frame
		 */
		clear_bit(PACKET_MERGE_SEGS, &pd->flags);
		return 0;
932
	} else if ((pd->settings.size << 9) / PAGE_SIZE
933
		   <= queue_max_segments(q)) {
L
Linus Torvalds 已提交
934 935 936 937 938 939 940
		/*
		 * 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 {
941
		pkt_err(pd, "cdrom max_phys_segments too small\n");
L
Linus Torvalds 已提交
942 943 944 945
		return -EIO;
	}
}

946
static void pkt_end_io_read(struct bio *bio)
L
Linus Torvalds 已提交
947 948 949 950 951
{
	struct packet_data *pkt = bio->bi_private;
	struct pktcdvd_device *pd = pkt->pd;
	BUG_ON(!pd);

952
	pkt_dbg(2, pd, "bio=%p sec0=%llx sec=%llx err=%d\n",
953
		bio, (unsigned long long)pkt->sector,
954
		(unsigned long long)bio->bi_iter.bi_sector, bio->bi_status);
L
Linus Torvalds 已提交
955

956
	if (bio->bi_status)
L
Linus Torvalds 已提交
957 958 959 960 961 962 963 964
		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);
}

965
static void pkt_end_io_packet_write(struct bio *bio)
L
Linus Torvalds 已提交
966 967 968 969 970
{
	struct packet_data *pkt = bio->bi_private;
	struct pktcdvd_device *pd = pkt->pd;
	BUG_ON(!pd);

971
	pkt_dbg(2, pd, "id=%d, err=%d\n", pkt->id, bio->bi_status);
L
Linus Torvalds 已提交
972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990

	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];

991
	BUG_ON(bio_list_empty(&pkt->orig_bios));
L
Linus Torvalds 已提交
992 993 994 995 996 997 998 999 1000

	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);
1001
	bio_list_for_each(bio, &pkt->orig_bios) {
1002 1003 1004
		int first_frame = (bio->bi_iter.bi_sector - pkt->sector) /
			(CD_FRAMESIZE >> 9);
		int num_frames = bio->bi_iter.bi_size / CD_FRAMESIZE;
1005
		pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
L
Linus Torvalds 已提交
1006 1007 1008 1009 1010 1011 1012
		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);

1013
	if (pkt->cache_valid) {
1014
		pkt_dbg(2, pd, "zone %llx cached\n",
1015 1016 1017 1018
			(unsigned long long)pkt->sector);
		goto out_account;
	}

L
Linus Torvalds 已提交
1019 1020 1021 1022 1023
	/*
	 * Schedule reads for missing parts of the packet.
	 */
	for (f = 0; f < pkt->frames; f++) {
		int p, offset;
1024

L
Linus Torvalds 已提交
1025 1026
		if (written[f])
			continue;
1027

L
Linus Torvalds 已提交
1028
		bio = pkt->r_bios[f];
1029
		bio_reset(bio);
1030
		bio->bi_iter.bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
L
Linus Torvalds 已提交
1031 1032 1033 1034 1035 1036
		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;
1037
		pkt_dbg(2, pd, "Adding frame %d, page:%p offs:%d\n",
L
Linus Torvalds 已提交
1038 1039 1040 1041 1042
			f, pkt->pages[p], offset);
		if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
			BUG();

		atomic_inc(&pkt->io_wait);
1043
		bio_set_op_attrs(bio, REQ_OP_READ, 0);
1044
		pkt_queue_bio(pd, bio);
L
Linus Torvalds 已提交
1045 1046 1047 1048
		frames_read++;
	}

out_account:
1049
	pkt_dbg(2, pd, "need %d frames for zone %llx\n",
L
Linus Torvalds 已提交
1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067
		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;
1068
			return pkt;
L
Linus Torvalds 已提交
1069 1070
		}
	}
1071 1072
	BUG();
	return NULL;
L
Linus Torvalds 已提交
1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113
}

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;

1114
	if (!sb->s_op->relocate_blocks)
L
Linus Torvalds 已提交
1115 1116 1117 1118 1119 1120 1121 1122 1123
		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;

1124 1125
	bio_reset(pkt->bio);
	pkt->bio->bi_bdev = pd->bdev;
J
Jens Axboe 已提交
1126
	bio_set_op_attrs(pkt->bio, REQ_OP_WRITE, 0);
1127 1128
	pkt->bio->bi_iter.bi_sector = new_sector;
	pkt->bio->bi_iter.bi_size = pkt->frames * CD_FRAMESIZE;
1129
	pkt->bio->bi_vcnt = pkt->frames;
L
Linus Torvalds 已提交
1130

1131 1132
	pkt->bio->bi_end_io = pkt_end_io_packet_write;
	pkt->bio->bi_private = pkt;
L
Linus Torvalds 已提交
1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149

	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;
1150
	pkt_dbg(2, pd, "pkt %2d : s=%6llx %s -> %s\n",
1151
		pkt->id, (unsigned long long)pkt->sector,
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		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;
1168
	int wakeup;
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	atomic_set(&pd->scan_queue, 0);

	if (list_empty(&pd->cdrw.pkt_free_list)) {
1173
		pkt_dbg(2, pd, "no pkt\n");
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		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;
1190
		zone = get_zone(bio->bi_iter.bi_sector, pd);
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		list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1192 1193
			if (p->sector == zone) {
				bio = NULL;
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				goto try_next_bio;
1195
			}
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		}
		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) {
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		pkt_dbg(2, pd, "no bio\n");
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		return 0;
	}

	pkt = pkt_get_packet_data(pd, zone);

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

	/*
	 * Scan work queue for bios in the same zone and link them
	 * to this packet.
	 */
	spin_lock(&pd->lock);
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	pkt_dbg(2, pd, "looking for zone %llx\n", (unsigned long long)zone);
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	while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
		bio = node->bio;
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		pkt_dbg(2, pd, "found zone=%llx\n", (unsigned long long)
			get_zone(bio->bi_iter.bi_sector, pd));
		if (get_zone(bio->bi_iter.bi_sector, pd) != zone)
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			break;
		pkt_rbtree_erase(pd, node);
		spin_lock(&pkt->lock);
1235
		bio_list_add(&pkt->orig_bios, bio);
1236
		pkt->write_size += bio->bi_iter.bi_size / CD_FRAMESIZE;
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		spin_unlock(&pkt->lock);
	}
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	/* 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);
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	spin_unlock(&pd->lock);
1244
	if (wakeup) {
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		clear_bdi_congested(pd->disk->queue->backing_dev_info,
1246 1247
					BLK_RW_ASYNC);
	}
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	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;

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	bio_reset(pkt->w_bio);
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	pkt->w_bio->bi_iter.bi_sector = pkt->sector;
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	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? */
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	for (f = 0; f < pkt->frames; f++) {
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		struct page *page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
		unsigned offset = (f * CD_FRAMESIZE) % PAGE_SIZE;

		if (!bio_add_page(pkt->w_bio, page, CD_FRAMESIZE, offset))
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			BUG();
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	}
1282
	pkt_dbg(2, pd, "vcnt=%d\n", pkt->w_bio->bi_vcnt);
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	/*
1285
	 * Fill-in bvec with data from orig_bios.
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	 */
	spin_lock(&pkt->lock);
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	bio_copy_data(pkt->w_bio, pkt->orig_bios.head);
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	pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
	spin_unlock(&pkt->lock);

1293
	pkt_dbg(2, pd, "Writing %d frames for zone %llx\n",
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		pkt->write_size, (unsigned long long)pkt->sector);
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1296
	if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames))
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		pkt->cache_valid = 1;
1298
	else
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		pkt->cache_valid = 0;

	/* Start the write request */
	atomic_set(&pkt->io_wait, 1);
1303
	bio_set_op_attrs(pkt->w_bio, REQ_OP_WRITE, 0);
1304
	pkt_queue_bio(pd, pkt->w_bio);
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}

1307
static void pkt_finish_packet(struct packet_data *pkt, blk_status_t status)
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{
1309
	struct bio *bio;
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1311
	if (status)
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		pkt->cache_valid = 0;

	/* Finish all bios corresponding to this packet */
1315
	while ((bio = bio_list_pop(&pkt->orig_bios))) {
1316
		bio->bi_status = status;
1317 1318
		bio_endio(bio);
	}
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}

static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
{
1323
	pkt_dbg(2, pd, "pkt %d\n", pkt->id);
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	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;

1351
			if (!pkt->w_bio->bi_status) {
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				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 {
1362
				pkt_dbg(2, pd, "No recovery possible\n");
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				pkt_set_state(pkt, PACKET_FINISHED_STATE);
			}
			break;

		case PACKET_FINISHED_STATE:
1368
			pkt_finish_packet(pkt, pkt->w_bio->bi_status);
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			return;

		default:
			BUG();
			break;
		}
	}
}

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

	/*
	 * 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;

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	for (i = 0; i < PACKET_NUM_STATES; i++)
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		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;

1432
	set_user_nice(current, MIN_NICE);
1433
	set_freezable();
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	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);
1463
				pkt_dbg(2, pd, "i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1464 1465
					states[0], states[1], states[2],
					states[3], states[4], states[5]);
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			}

			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;
			}

1474
			pkt_dbg(2, pd, "sleeping\n");
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			residue = schedule_timeout(min_sleep_time);
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			pkt_dbg(2, pd, "wake up\n");
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			/* make swsusp happy with our thread */
1479
			try_to_freeze();
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			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)
{
1524 1525 1526 1527
	pkt_info(pd, "%s packets, %u blocks, Mode-%c disc\n",
		 pd->settings.fp ? "Fixed" : "Variable",
		 pd->settings.size >> 2,
		 pd->settings.block_mode == 8 ? '1' : '2');
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}

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);
}

1607 1608
static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
						long *last_written)
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{
	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
 */
1645
static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
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{
	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))) {
1661
		pkt_dump_sense(pd, &cgc);
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		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))) {
1676
		pkt_dump_sense(pd, &cgc);
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		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
		 */
1711
		pkt_err(pd, "write mode wrong %d\n", wp->data_block_type);
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		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))) {
1718
		pkt_dump_sense(pd, &cgc);
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		return ret;
	}

	pkt_print_settings(pd);
	return 0;
}

/*
1727
 * 1 -- we can write to this track, 0 -- we can't
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 */
1729
static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
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{
1731 1732 1733 1734 1735 1736 1737 1738
	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;
	}
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1740 1741
	if (!ti->packet || !ti->fp)
		return 0;
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1742 1743 1744 1745

	/*
	 * "good" settings as per Mt Fuji.
	 */
1746
	if (ti->rt == 0 && ti->blank == 0)
1747
		return 1;
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1748

1749
	if (ti->rt == 0 && ti->blank == 1)
1750
		return 1;
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1751

1752
	if (ti->rt == 1 && ti->blank == 0)
1753
		return 1;
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1755
	pkt_err(pd, "bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1756
	return 0;
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}

/*
1760
 * 1 -- we can write to this disc, 0 -- we can't
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 */
1762
static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
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{
	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 */
1771
			return 1;
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		default:
1773
			pkt_dbg(2, pd, "Wrong disc profile (%x)\n",
1774
				pd->mmc3_profile);
1775
			return 0;
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	}

	/*
	 * 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) {
1783
		pkt_notice(pd, "unknown disc - no track?\n");
1784
		return 0;
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	}

	if (di->disc_type != 0x20 && di->disc_type != 0) {
1788
		pkt_err(pd, "wrong disc type (%x)\n", di->disc_type);
1789
		return 0;
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	}

	if (di->erasable == 0) {
1793
		pkt_notice(pd, "disc not erasable\n");
1794
		return 0;
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	}

	if (di->border_status == PACKET_SESSION_RESERVED) {
1798
		pkt_err(pd, "can't write to last track (reserved)\n");
1799
		return 0;
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	}

1802
	return 1;
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}

1805
static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
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{
	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))) {
1823
		pkt_err(pd, "failed get_disc\n");
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		return ret;
	}

1827
	if (!pkt_writable_disc(pd, &di))
1828
		return -EROFS;
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1829 1830 1831 1832 1833

	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))) {
1834
		pkt_err(pd, "failed get_track\n");
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		return ret;
	}

1838
	if (!pkt_writable_track(pd, &ti)) {
1839
		pkt_err(pd, "can't write to this track\n");
1840
		return -EROFS;
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	}

	/*
	 * 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) {
1849
		pkt_notice(pd, "detected zero packet size!\n");
1850
		return -ENXIO;
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1851
	}
1852
	if (pd->settings.size > PACKET_MAX_SECTORS) {
1853
		pkt_err(pd, "packet size is too big\n");
1854
		return -EROFS;
1855
	}
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1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894
	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:
1895
			pkt_err(pd, "unknown data mode\n");
1896
			return -EROFS;
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	}
	return 0;
}

/*
 * enable/disable write caching on drive
 */
1904 1905
static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
						int set)
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{
	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) {
1929
		pkt_err(pd, "write caching control failed\n");
1930
		pkt_dump_sense(pd, &cgc);
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1931
	} else if (!ret && set)
1932
		pkt_notice(pd, "enabled write caching\n");
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	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
 */
1949 1950
static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
						unsigned *write_speed)
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1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967
{
	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) {
1968
			pkt_dump_sense(pd, &cgc);
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1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
			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
 */
2010 2011
static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
						unsigned *speed)
L
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2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026
{
	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) {
2027
		pkt_dump_sense(pd, &cgc);
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Linus Torvalds 已提交
2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041
		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) {
2042
		pkt_dump_sense(pd, &cgc);
L
Linus Torvalds 已提交
2043 2044 2045
		return ret;
	}

2046
	if (!(buf[6] & 0x40)) {
2047
		pkt_notice(pd, "disc type is not CD-RW\n");
L
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2048 2049
		return 1;
	}
2050
	if (!(buf[6] & 0x4)) {
2051
		pkt_notice(pd, "A1 values on media are not valid, maybe not CDRW?\n");
L
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2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070
		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:
2071
			pkt_notice(pd, "unknown disc sub-type %d\n", st);
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Linus Torvalds 已提交
2072 2073 2074
			return 1;
	}
	if (*speed) {
2075
		pkt_info(pd, "maximum media speed: %d\n", *speed);
L
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2076 2077
		return 0;
	} else {
2078
		pkt_notice(pd, "unknown speed %d for sub-type %d\n", sp, st);
L
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2079 2080 2081 2082
		return 1;
	}
}

2083
static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
L
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2084 2085 2086 2087 2088
{
	struct packet_command cgc;
	struct request_sense sense;
	int ret;

2089
	pkt_dbg(2, pd, "Performing OPC\n");
L
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2090 2091 2092 2093 2094 2095 2096

	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)))
2097
		pkt_dump_sense(pd, &cgc);
L
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2098 2099 2100 2101 2102 2103 2104 2105 2106
	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))) {
2107
		pkt_dbg(2, pd, "failed probe\n");
2108
		return ret;
L
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2109 2110 2111
	}

	if ((ret = pkt_set_write_settings(pd))) {
2112
		pkt_dbg(1, pd, "failed saving write settings\n");
L
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2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123
		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 */
2124
			pkt_dbg(1, pd, "write speed %ukB/s\n", write_speed);
L
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2125 2126 2127 2128 2129
			break;
		default:
			if ((ret = pkt_media_speed(pd, &media_write_speed)))
				media_write_speed = 16;
			write_speed = min(write_speed, media_write_speed * 177);
2130
			pkt_dbg(1, pd, "write speed %ux\n", write_speed / 176);
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2131 2132 2133 2134 2135
			break;
	}
	read_speed = write_speed;

	if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
2136
		pkt_dbg(1, pd, "couldn't set write speed\n");
L
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2137 2138 2139 2140 2141 2142
		return -EIO;
	}
	pd->write_speed = write_speed;
	pd->read_speed = read_speed;

	if ((ret = pkt_perform_opc(pd))) {
2143
		pkt_dbg(1, pd, "Optimum Power Calibration failed\n");
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2144 2145 2146 2147 2148 2149 2150 2151
	}

	return 0;
}

/*
 * called at open time.
 */
2152
static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
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2153 2154 2155
{
	int ret;
	long lba;
2156
	struct request_queue *q;
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2157 2158 2159 2160 2161 2162 2163

	/*
	 * 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);
2164
	if ((ret = blkdev_get(pd->bdev, FMODE_READ | FMODE_EXCL, pd)))
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2165 2166 2167
		goto out;

	if ((ret = pkt_get_last_written(pd, &lba))) {
2168
		pkt_err(pd, "pkt_get_last_written failed\n");
2169
		goto out_putdev;
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2170 2171 2172 2173 2174 2175 2176 2177 2178
	}

	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)))
2179
			goto out_putdev;
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2180 2181 2182 2183 2184
		/*
		 * 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);
2185
		blk_queue_max_hw_sectors(q, pd->settings.size);
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2186 2187 2188 2189 2190 2191 2192 2193
		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)))
2194
		goto out_putdev;
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2195

2196 2197
	if (write) {
		if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2198
			pkt_err(pd, "not enough memory for buffers\n");
2199
			ret = -ENOMEM;
2200
			goto out_putdev;
2201
		}
2202
		pkt_info(pd, "%lukB available on disc\n", lba << 1);
2203
	}
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2204 2205 2206 2207

	return 0;

out_putdev:
2208
	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
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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))
2220
		pkt_dbg(1, pd, "not flushing cache\n");
L
Linus Torvalds 已提交
2221 2222 2223 2224

	pkt_lock_door(pd, 0);

	pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2225
	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2226 2227

	pkt_shrink_pktlist(pd);
L
Linus Torvalds 已提交
2228 2229
}

2230
static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
L
Linus Torvalds 已提交
2231 2232 2233 2234 2235 2236
{
	if (dev_minor >= MAX_WRITERS)
		return NULL;
	return pkt_devs[dev_minor];
}

A
Al Viro 已提交
2237
static int pkt_open(struct block_device *bdev, fmode_t mode)
L
Linus Torvalds 已提交
2238 2239 2240 2241
{
	struct pktcdvd_device *pd = NULL;
	int ret;

2242
	mutex_lock(&pktcdvd_mutex);
2243
	mutex_lock(&ctl_mutex);
A
Al Viro 已提交
2244
	pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
L
Linus Torvalds 已提交
2245 2246 2247 2248 2249 2250 2251
	if (!pd) {
		ret = -ENODEV;
		goto out;
	}
	BUG_ON(pd->refcnt < 0);

	pd->refcnt++;
2252
	if (pd->refcnt > 1) {
A
Al Viro 已提交
2253
		if ((mode & FMODE_WRITE) &&
2254 2255 2256 2257 2258
		    !test_bit(PACKET_WRITABLE, &pd->flags)) {
			ret = -EBUSY;
			goto out_dec;
		}
	} else {
A
Al Viro 已提交
2259
		ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2260
		if (ret)
L
Linus Torvalds 已提交
2261 2262 2263 2264 2265
			goto out_dec;
		/*
		 * needed here as well, since ext2 (among others) may change
		 * the blocksize at mount time
		 */
A
Al Viro 已提交
2266
		set_blocksize(bdev, CD_FRAMESIZE);
L
Linus Torvalds 已提交
2267 2268
	}

2269
	mutex_unlock(&ctl_mutex);
2270
	mutex_unlock(&pktcdvd_mutex);
L
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2271 2272 2273 2274 2275
	return 0;

out_dec:
	pd->refcnt--;
out:
2276
	mutex_unlock(&ctl_mutex);
2277
	mutex_unlock(&pktcdvd_mutex);
L
Linus Torvalds 已提交
2278 2279 2280
	return ret;
}

2281
static void pkt_close(struct gendisk *disk, fmode_t mode)
L
Linus Torvalds 已提交
2282
{
A
Al Viro 已提交
2283
	struct pktcdvd_device *pd = disk->private_data;
L
Linus Torvalds 已提交
2284

2285
	mutex_lock(&pktcdvd_mutex);
2286
	mutex_lock(&ctl_mutex);
L
Linus Torvalds 已提交
2287 2288 2289 2290 2291 2292
	pd->refcnt--;
	BUG_ON(pd->refcnt < 0);
	if (pd->refcnt == 0) {
		int flush = test_bit(PACKET_WRITABLE, &pd->flags);
		pkt_release_dev(pd, flush);
	}
2293
	mutex_unlock(&ctl_mutex);
2294
	mutex_unlock(&pktcdvd_mutex);
L
Linus Torvalds 已提交
2295 2296 2297
}


2298
static void pkt_end_io_read_cloned(struct bio *bio)
L
Linus Torvalds 已提交
2299 2300 2301 2302
{
	struct packet_stacked_data *psd = bio->bi_private;
	struct pktcdvd_device *pd = psd->pd;

2303
	psd->bio->bi_status = bio->bi_status;
L
Linus Torvalds 已提交
2304
	bio_put(bio);
2305
	bio_endio(psd->bio);
L
Linus Torvalds 已提交
2306 2307 2308 2309
	mempool_free(psd, psd_pool);
	pkt_bio_finished(pd);
}

K
Kent Overstreet 已提交
2310
static void pkt_make_request_read(struct pktcdvd_device *pd, struct bio *bio)
L
Linus Torvalds 已提交
2311
{
2312
	struct bio *cloned_bio = bio_clone_fast(bio, GFP_NOIO, pkt_bio_set);
K
Kent Overstreet 已提交
2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326
	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);
}

static void pkt_make_request_write(struct request_queue *q, struct bio *bio)
{
	struct pktcdvd_device *pd = q->queuedata;
L
Linus Torvalds 已提交
2327 2328 2329 2330 2331
	sector_t zone;
	struct packet_data *pkt;
	int was_empty, blocked_bio;
	struct pkt_rb_node *node;

2332
	zone = get_zone(bio->bi_iter.bi_sector, pd);
L
Linus Torvalds 已提交
2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344

	/*
	 * 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)) {
2345
				bio_list_add(&pkt->orig_bios, bio);
2346 2347
				pkt->write_size +=
					bio->bi_iter.bi_size / CD_FRAMESIZE;
L
Linus Torvalds 已提交
2348 2349 2350 2351 2352 2353 2354
				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);
2355
				return;
L
Linus Torvalds 已提交
2356 2357 2358 2359 2360 2361 2362 2363
			} else {
				blocked_bio = 1;
			}
			spin_unlock(&pkt->lock);
		}
	}
	spin_unlock(&pd->cdrw.active_list_lock);

2364 2365 2366 2367 2368 2369 2370 2371
 	/*
	 * 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) {
2372
		set_bdi_congested(q->backing_dev_info, BLK_RW_ASYNC);
2373 2374
		do {
			spin_unlock(&pd->lock);
2375
			congestion_wait(BLK_RW_ASYNC, HZ);
2376 2377 2378 2379 2380
			spin_lock(&pd->lock);
		} while(pd->bio_queue_size > pd->write_congestion_off);
	}
	spin_unlock(&pd->lock);

L
Linus Torvalds 已提交
2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405
	/*
	 * 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);
	}
K
Kent Overstreet 已提交
2406 2407
}

2408
static blk_qc_t pkt_make_request(struct request_queue *q, struct bio *bio)
K
Kent Overstreet 已提交
2409 2410 2411 2412 2413
{
	struct pktcdvd_device *pd;
	char b[BDEVNAME_SIZE];
	struct bio *split;

2414
	blk_queue_split(q, &bio);
2415

K
Kent Overstreet 已提交
2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431
	pd = q->queuedata;
	if (!pd) {
		pr_err("%s incorrect request queue\n",
		       bdevname(bio->bi_bdev, b));
		goto end_io;
	}

	pkt_dbg(2, pd, "start = %6llx stop = %6llx\n",
		(unsigned long long)bio->bi_iter.bi_sector,
		(unsigned long long)bio_end_sector(bio));

	/*
	 * Clone READ bios so we can have our own bi_end_io callback.
	 */
	if (bio_data_dir(bio) == READ) {
		pkt_make_request_read(pd, bio);
2432
		return BLK_QC_T_NONE;
K
Kent Overstreet 已提交
2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454
	}

	if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
		pkt_notice(pd, "WRITE for ro device (%llu)\n",
			   (unsigned long long)bio->bi_iter.bi_sector);
		goto end_io;
	}

	if (!bio->bi_iter.bi_size || (bio->bi_iter.bi_size % CD_FRAMESIZE)) {
		pkt_err(pd, "wrong bio size\n");
		goto end_io;
	}

	do {
		sector_t zone = get_zone(bio->bi_iter.bi_sector, pd);
		sector_t last_zone = get_zone(bio_end_sector(bio) - 1, pd);

		if (last_zone != zone) {
			BUG_ON(last_zone != zone + pd->settings.size);

			split = bio_split(bio, last_zone -
					  bio->bi_iter.bi_sector,
2455
					  GFP_NOIO, pkt_bio_set);
K
Kent Overstreet 已提交
2456 2457 2458 2459 2460 2461 2462 2463
			bio_chain(split, bio);
		} else {
			split = bio;
		}

		pkt_make_request_write(q, split);
	} while (split != bio);

2464
	return BLK_QC_T_NONE;
L
Linus Torvalds 已提交
2465
end_io:
2466
	bio_io_error(bio);
2467
	return BLK_QC_T_NONE;
L
Linus Torvalds 已提交
2468 2469 2470 2471
}

static void pkt_init_queue(struct pktcdvd_device *pd)
{
2472
	struct request_queue *q = pd->disk->queue;
L
Linus Torvalds 已提交
2473 2474

	blk_queue_make_request(q, pkt_make_request);
2475
	blk_queue_logical_block_size(q, CD_FRAMESIZE);
2476
	blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
L
Linus Torvalds 已提交
2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535
	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]);

2536 2537 2538
	seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
			pd->write_congestion_off,
			pd->write_congestion_on);
L
Linus Torvalds 已提交
2539 2540 2541 2542 2543
	return 0;
}

static int pkt_seq_open(struct inode *inode, struct file *file)
{
A
Al Viro 已提交
2544
	return single_open(file, pkt_seq_show, PDE_DATA(inode));
L
Linus Torvalds 已提交
2545 2546
}

2547
static const struct file_operations pkt_proc_fops = {
L
Linus Torvalds 已提交
2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561
	.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) {
2562
		pkt_err(pd, "recursive setup not allowed\n");
L
Linus Torvalds 已提交
2563 2564 2565 2566 2567 2568 2569
		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) {
2570 2571
			pkt_err(pd, "%s already setup\n",
				bdevname(pd2->bdev, b));
L
Linus Torvalds 已提交
2572 2573 2574
			return -EBUSY;
		}
		if (pd2->pkt_dev == dev) {
2575
			pkt_err(pd, "can't chain pktcdvd devices\n");
L
Linus Torvalds 已提交
2576 2577 2578 2579 2580 2581 2582
			return -EBUSY;
		}
	}

	bdev = bdget(dev);
	if (!bdev)
		return -ENOMEM;
2583 2584 2585 2586 2587
	if (!blk_queue_scsi_passthrough(bdev_get_queue(bdev))) {
		WARN_ONCE(true, "Attempt to register a non-SCSI queue\n");
		bdput(bdev);
		return -EINVAL;
	}
2588
	ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL);
L
Linus Torvalds 已提交
2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602
	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)) {
2603
		pkt_err(pd, "can't start kernel thread\n");
L
Linus Torvalds 已提交
2604
		ret = -ENOMEM;
2605
		goto out_mem;
L
Linus Torvalds 已提交
2606 2607
	}

2608
	proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd);
2609
	pkt_dbg(1, pd, "writer mapped to %s\n", bdevname(bdev, b));
L
Linus Torvalds 已提交
2610 2611 2612
	return 0;

out_mem:
2613
	blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
L
Linus Torvalds 已提交
2614 2615 2616 2617 2618
	/* This is safe: open() is still holding a reference. */
	module_put(THIS_MODULE);
	return ret;
}

A
Al Viro 已提交
2619
static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
L
Linus Torvalds 已提交
2620
{
A
Al Viro 已提交
2621
	struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2622
	int ret;
L
Linus Torvalds 已提交
2623

2624
	pkt_dbg(2, pd, "cmd %x, dev %d:%d\n",
2625
		cmd, MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
L
Linus Torvalds 已提交
2626

2627
	mutex_lock(&pktcdvd_mutex);
L
Linus Torvalds 已提交
2628
	switch (cmd) {
2629 2630 2631 2632 2633 2634 2635 2636
	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 */
L
Linus Torvalds 已提交
2637 2638 2639 2640 2641 2642 2643 2644
	/*
	 * 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:
2645 2646
		ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
		break;
L
Linus Torvalds 已提交
2647 2648

	default:
2649
		pkt_dbg(2, pd, "Unknown ioctl (%x)\n", cmd);
2650
		ret = -ENOTTY;
L
Linus Torvalds 已提交
2651
	}
2652
	mutex_unlock(&pktcdvd_mutex);
2653

2654
	return ret;
L
Linus Torvalds 已提交
2655 2656
}

2657 2658
static unsigned int pkt_check_events(struct gendisk *disk,
				     unsigned int clearing)
L
Linus Torvalds 已提交
2659 2660 2661 2662 2663 2664 2665 2666 2667
{
	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;
2668
	if (!attached_disk || !attached_disk->fops->check_events)
L
Linus Torvalds 已提交
2669
		return 0;
2670
	return attached_disk->fops->check_events(attached_disk, clearing);
L
Linus Torvalds 已提交
2671 2672
}

2673
static const struct block_device_operations pktcdvd_ops = {
L
Linus Torvalds 已提交
2674
	.owner =		THIS_MODULE,
A
Al Viro 已提交
2675 2676
	.open =			pkt_open,
	.release =		pkt_close,
2677
	.ioctl =		pkt_ioctl,
2678
	.check_events =		pkt_check_events,
L
Linus Torvalds 已提交
2679 2680
};

2681
static char *pktcdvd_devnode(struct gendisk *gd, umode_t *mode)
2682 2683 2684 2685
{
	return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
}

L
Linus Torvalds 已提交
2686 2687 2688
/*
 * Set up mapping from pktcdvd device to CD-ROM device.
 */
2689
static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
L
Linus Torvalds 已提交
2690 2691 2692 2693 2694
{
	int idx;
	int ret = -ENOMEM;
	struct pktcdvd_device *pd;
	struct gendisk *disk;
2695 2696

	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
L
Linus Torvalds 已提交
2697 2698 2699 2700 2701

	for (idx = 0; idx < MAX_WRITERS; idx++)
		if (!pkt_devs[idx])
			break;
	if (idx == MAX_WRITERS) {
2702
		pr_err("max %d writers supported\n", MAX_WRITERS);
2703 2704
		ret = -EBUSY;
		goto out_mutex;
L
Linus Torvalds 已提交
2705 2706
	}

2707
	pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
L
Linus Torvalds 已提交
2708
	if (!pd)
2709
		goto out_mutex;
L
Linus Torvalds 已提交
2710

2711 2712
	pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
						  sizeof(struct pkt_rb_node));
L
Linus Torvalds 已提交
2713 2714 2715
	if (!pd->rb_pool)
		goto out_mem;

2716 2717 2718 2719
	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
	INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
	spin_lock_init(&pd->cdrw.active_list_lock);

L
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2720 2721
	spin_lock_init(&pd->lock);
	spin_lock_init(&pd->iosched.lock);
2722 2723
	bio_list_init(&pd->iosched.read_queue);
	bio_list_init(&pd->iosched.write_queue);
2724
	sprintf(pd->name, DRIVER_NAME"%d", idx);
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2725 2726 2727
	init_waitqueue_head(&pd->wqueue);
	pd->bio_queue = RB_ROOT;

2728 2729 2730
	pd->write_congestion_on  = write_congestion_on;
	pd->write_congestion_off = write_congestion_off;

2731 2732 2733 2734
	disk = alloc_disk(1);
	if (!disk)
		goto out_mem;
	pd->disk = disk;
2735
	disk->major = pktdev_major;
L
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2736 2737 2738
	disk->first_minor = idx;
	disk->fops = &pktcdvd_ops;
	disk->flags = GENHD_FL_REMOVABLE;
2739
	strcpy(disk->disk_name, pd->name);
2740
	disk->devnode = pktcdvd_devnode;
L
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2741 2742 2743 2744 2745
	disk->private_data = pd;
	disk->queue = blk_alloc_queue(GFP_KERNEL);
	if (!disk->queue)
		goto out_mem2;

2746
	pd->pkt_dev = MKDEV(pktdev_major, idx);
L
Linus Torvalds 已提交
2747 2748 2749 2750
	ret = pkt_new_dev(pd, dev);
	if (ret)
		goto out_new_dev;

2751 2752 2753 2754
	/* inherit events of the host device */
	disk->events = pd->bdev->bd_disk->events;
	disk->async_events = pd->bdev->bd_disk->async_events;

L
Linus Torvalds 已提交
2755
	add_disk(disk);
2756

2757 2758 2759
	pkt_sysfs_dev_new(pd);
	pkt_debugfs_dev_new(pd);

L
Linus Torvalds 已提交
2760
	pkt_devs[idx] = pd;
2761 2762 2763 2764
	if (pkt_dev)
		*pkt_dev = pd->pkt_dev;

	mutex_unlock(&ctl_mutex);
L
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2765 2766 2767
	return 0;

out_new_dev:
2768
	blk_cleanup_queue(disk->queue);
L
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2769 2770 2771
out_mem2:
	put_disk(disk);
out_mem:
2772
	mempool_destroy(pd->rb_pool);
L
Linus Torvalds 已提交
2773
	kfree(pd);
2774 2775
out_mutex:
	mutex_unlock(&ctl_mutex);
2776
	pr_err("setup of pktcdvd device failed\n");
L
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2777 2778 2779 2780 2781 2782
	return ret;
}

/*
 * Tear down mapping from pktcdvd device to CD-ROM device.
 */
2783
static int pkt_remove_dev(dev_t pkt_dev)
L
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2784 2785 2786
{
	struct pktcdvd_device *pd;
	int idx;
2787 2788 2789
	int ret = 0;

	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
L
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2790 2791 2792 2793 2794 2795 2796

	for (idx = 0; idx < MAX_WRITERS; idx++) {
		pd = pkt_devs[idx];
		if (pd && (pd->pkt_dev == pkt_dev))
			break;
	}
	if (idx == MAX_WRITERS) {
2797
		pr_debug("dev not setup\n");
2798 2799
		ret = -ENXIO;
		goto out;
L
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2800 2801
	}

2802 2803 2804 2805
	if (pd->refcnt > 0) {
		ret = -EBUSY;
		goto out;
	}
L
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2806 2807 2808
	if (!IS_ERR(pd->cdrw.thread))
		kthread_stop(pd->cdrw.thread);

2809 2810 2811 2812 2813
	pkt_devs[idx] = NULL;

	pkt_debugfs_dev_remove(pd);
	pkt_sysfs_dev_remove(pd);

2814
	blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
L
Linus Torvalds 已提交
2815 2816

	remove_proc_entry(pd->name, pkt_proc);
2817
	pkt_dbg(1, pd, "writer unmapped\n");
L
Linus Torvalds 已提交
2818 2819

	del_gendisk(pd->disk);
2820
	blk_cleanup_queue(pd->disk->queue);
L
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2821 2822 2823 2824 2825 2826 2827
	put_disk(pd->disk);

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

	/* This is safe: open() is still holding a reference. */
	module_put(THIS_MODULE);
2828 2829 2830 2831

out:
	mutex_unlock(&ctl_mutex);
	return ret;
L
Linus Torvalds 已提交
2832 2833 2834 2835
}

static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
{
2836 2837 2838 2839 2840
	struct pktcdvd_device *pd;

	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);

	pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
L
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2841 2842 2843 2844 2845 2846 2847 2848
	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;
2849 2850

	mutex_unlock(&ctl_mutex);
L
Linus Torvalds 已提交
2851 2852
}

2853
static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
L
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2854 2855 2856 2857
{
	void __user *argp = (void __user *)arg;
	struct pkt_ctrl_command ctrl_cmd;
	int ret = 0;
2858
	dev_t pkt_dev = 0;
L
Linus Torvalds 已提交
2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869

	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;
2870 2871
		ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
		ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
L
Linus Torvalds 已提交
2872 2873 2874 2875
		break;
	case PKT_CTRL_CMD_TEARDOWN:
		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;
2876
		ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
L
Linus Torvalds 已提交
2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889
		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;
}

2890 2891 2892 2893 2894 2895
#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
L
Linus Torvalds 已提交
2896

2897
static const struct file_operations pkt_ctl_fops = {
2898 2899 2900 2901 2902 2903
	.open		= nonseekable_open,
	.unlocked_ioctl	= pkt_ctl_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl	= pkt_ctl_compat_ioctl,
#endif
	.owner		= THIS_MODULE,
2904
	.llseek		= no_llseek,
L
Linus Torvalds 已提交
2905 2906 2907 2908
};

static struct miscdevice pkt_misc = {
	.minor 		= MISC_DYNAMIC_MINOR,
2909
	.name  		= DRIVER_NAME,
2910
	.nodename	= "pktcdvd/control",
L
Linus Torvalds 已提交
2911 2912 2913 2914 2915 2916 2917
	.fops  		= &pkt_ctl_fops
};

static int __init pkt_init(void)
{
	int ret;

2918 2919
	mutex_init(&ctl_mutex);

2920 2921
	psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
					sizeof(struct packet_stacked_data));
L
Linus Torvalds 已提交
2922 2923
	if (!psd_pool)
		return -ENOMEM;
2924 2925 2926 2927 2928
	pkt_bio_set = bioset_create(BIO_POOL_SIZE, 0, 0);
	if (!pkt_bio_set) {
		mempool_destroy(psd_pool);
		return -ENOMEM;
	}
L
Linus Torvalds 已提交
2929

2930
	ret = register_blkdev(pktdev_major, DRIVER_NAME);
L
Linus Torvalds 已提交
2931
	if (ret < 0) {
2932
		pr_err("unable to register block device\n");
L
Linus Torvalds 已提交
2933 2934
		goto out2;
	}
2935 2936
	if (!pktdev_major)
		pktdev_major = ret;
L
Linus Torvalds 已提交
2937

2938 2939 2940 2941 2942 2943
	ret = pkt_sysfs_init();
	if (ret)
		goto out;

	pkt_debugfs_init();

L
Linus Torvalds 已提交
2944 2945
	ret = misc_register(&pkt_misc);
	if (ret) {
2946
		pr_err("unable to register misc device\n");
2947
		goto out_misc;
L
Linus Torvalds 已提交
2948 2949
	}

A
Alexey Dobriyan 已提交
2950
	pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
L
Linus Torvalds 已提交
2951 2952 2953

	return 0;

2954 2955 2956
out_misc:
	pkt_debugfs_cleanup();
	pkt_sysfs_cleanup();
L
Linus Torvalds 已提交
2957
out:
2958
	unregister_blkdev(pktdev_major, DRIVER_NAME);
L
Linus Torvalds 已提交
2959 2960
out2:
	mempool_destroy(psd_pool);
2961
	bioset_free(pkt_bio_set);
L
Linus Torvalds 已提交
2962 2963 2964 2965 2966
	return ret;
}

static void __exit pkt_exit(void)
{
A
Alexey Dobriyan 已提交
2967
	remove_proc_entry("driver/"DRIVER_NAME, NULL);
L
Linus Torvalds 已提交
2968
	misc_deregister(&pkt_misc);
2969 2970 2971 2972

	pkt_debugfs_cleanup();
	pkt_sysfs_cleanup();

2973
	unregister_blkdev(pktdev_major, DRIVER_NAME);
L
Linus Torvalds 已提交
2974
	mempool_destroy(psd_pool);
2975
	bioset_free(pkt_bio_set);
L
Linus Torvalds 已提交
2976 2977 2978 2979 2980 2981 2982 2983
}

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);