diff options
Diffstat (limited to 'drivers/block/pktcdvd.c')
-rw-r--r-- | drivers/block/pktcdvd.c | 3029 |
1 files changed, 3029 insertions, 0 deletions
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c new file mode 100644 index 000000000..09e628daf --- /dev/null +++ b/drivers/block/pktcdvd.c @@ -0,0 +1,3029 @@ +/* + * Copyright (C) 2000 Jens Axboe <axboe@suse.de> + * Copyright (C) 2001-2004 Peter Osterlund <petero2@telia.com> + * Copyright (C) 2006 Thomas Maier <balagi@justmail.de> + * + * May be copied or modified under the terms of the GNU General Public + * License. See linux/COPYING for more information. + * + * Packet writing layer for ATAPI and SCSI CD-RW, DVD+RW, DVD-RW and + * DVD-RAM devices. + * + * Theory of operation: + * + * 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. + * + *************************************************************************/ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/pktcdvd.h> +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/compat.h> +#include <linux/kthread.h> +#include <linux/errno.h> +#include <linux/spinlock.h> +#include <linux/file.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/miscdevice.h> +#include <linux/freezer.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <scsi/scsi_cmnd.h> +#include <scsi/scsi_ioctl.h> +#include <scsi/scsi.h> +#include <linux/debugfs.h> +#include <linux/device.h> + +#include <asm/uaccess.h> + +#define DRIVER_NAME "pktcdvd" + +#define pkt_err(pd, fmt, ...) \ + pr_err("%s: " fmt, pd->name, ##__VA_ARGS__) +#define pkt_notice(pd, fmt, ...) \ + pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__) +#define pkt_info(pd, fmt, ...) \ + pr_info("%s: " fmt, pd->name, ##__VA_ARGS__) + +#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__); \ +} while (0) + +#define MAX_SPEED 0xffff + +static DEFINE_MUTEX(pktcdvd_mutex); +static struct pktcdvd_device *pkt_devs[MAX_WRITERS]; +static struct proc_dir_entry *pkt_proc; +static int pktdev_major; +static int write_congestion_on = PKT_WRITE_CONGESTION_ON; +static int write_congestion_off = PKT_WRITE_CONGESTION_OFF; +static struct mutex ctl_mutex; /* Serialize open/close/setup/teardown */ +static mempool_t *psd_pool; + +static struct class *class_pktcdvd = NULL; /* /sys/class/pktcdvd */ +static struct dentry *pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */ + +/* forward declaration */ +static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev); +static int pkt_remove_dev(dev_t pkt_dev); +static int pkt_seq_show(struct seq_file *m, void *p); + +static sector_t get_zone(sector_t sector, struct pktcdvd_device *pd) +{ + return (sector + pd->offset) & ~(sector_t)(pd->settings.size - 1); +} + +/* + * create and register a pktcdvd kernel object. + */ +static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd, + const char* name, + struct kobject* parent, + struct kobj_type* ktype) +{ + struct pktcdvd_kobj *p; + int error; + + p = kzalloc(sizeof(*p), GFP_KERNEL); + if (!p) + return NULL; + p->pd = pd; + error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name); + if (error) { + kobject_put(&p->kobj); + return NULL; + } + kobject_uevent(&p->kobj, KOBJ_ADD); + return p; +} +/* + * remove a pktcdvd kernel object. + */ +static void pkt_kobj_remove(struct pktcdvd_kobj *p) +{ + if (p) + kobject_put(&p->kobj); +} +/* + * default release function for pktcdvd kernel objects. + */ +static void pkt_kobj_release(struct kobject *kobj) +{ + kfree(to_pktcdvdkobj(kobj)); +} + + +/********************************************************** + * + * sysfs interface for pktcdvd + * by (C) 2006 Thomas Maier <balagi@justmail.de> + * + **********************************************************/ + +#define DEF_ATTR(_obj,_name,_mode) \ + static struct attribute _obj = { .name = _name, .mode = _mode } + +/********************************************************** + /sys/class/pktcdvd/pktcdvd[0-7]/ + stat/reset + stat/packets_started + stat/packets_finished + stat/kb_written + stat/kb_read + stat/kb_read_gather + write_queue/size + write_queue/congestion_off + write_queue/congestion_on + **********************************************************/ + +DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200); +DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444); +DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444); +DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444); +DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444); +DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444); + +static struct attribute *kobj_pkt_attrs_stat[] = { + &kobj_pkt_attr_st1, + &kobj_pkt_attr_st2, + &kobj_pkt_attr_st3, + &kobj_pkt_attr_st4, + &kobj_pkt_attr_st5, + &kobj_pkt_attr_st6, + NULL +}; + +DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444); +DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644); +DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on", 0644); + +static struct attribute *kobj_pkt_attrs_wqueue[] = { + &kobj_pkt_attr_wq1, + &kobj_pkt_attr_wq2, + &kobj_pkt_attr_wq3, + NULL +}; + +static ssize_t kobj_pkt_show(struct kobject *kobj, + struct attribute *attr, char *data) +{ + struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd; + int n = 0; + int v; + if (strcmp(attr->name, "packets_started") == 0) { + n = sprintf(data, "%lu\n", pd->stats.pkt_started); + + } else if (strcmp(attr->name, "packets_finished") == 0) { + n = sprintf(data, "%lu\n", pd->stats.pkt_ended); + + } else if (strcmp(attr->name, "kb_written") == 0) { + n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1); + + } else if (strcmp(attr->name, "kb_read") == 0) { + n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1); + + } else if (strcmp(attr->name, "kb_read_gather") == 0) { + n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1); + + } else if (strcmp(attr->name, "size") == 0) { + spin_lock(&pd->lock); + v = pd->bio_queue_size; + spin_unlock(&pd->lock); + n = sprintf(data, "%d\n", v); + + } else if (strcmp(attr->name, "congestion_off") == 0) { + spin_lock(&pd->lock); + v = pd->write_congestion_off; + spin_unlock(&pd->lock); + n = sprintf(data, "%d\n", v); + + } else if (strcmp(attr->name, "congestion_on") == 0) { + spin_lock(&pd->lock); + v = pd->write_congestion_on; + spin_unlock(&pd->lock); + n = sprintf(data, "%d\n", v); + } + return n; +} + +static void init_write_congestion_marks(int* lo, int* hi) +{ + if (*hi > 0) { + *hi = max(*hi, 500); + *hi = min(*hi, 1000000); + if (*lo <= 0) + *lo = *hi - 100; + else { + *lo = min(*lo, *hi - 100); + *lo = max(*lo, 100); + } + } else { + *hi = -1; + *lo = -1; + } +} + +static ssize_t kobj_pkt_store(struct kobject *kobj, + struct attribute *attr, + const char *data, size_t len) +{ + struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd; + int val; + + if (strcmp(attr->name, "reset") == 0 && len > 0) { + pd->stats.pkt_started = 0; + pd->stats.pkt_ended = 0; + pd->stats.secs_w = 0; + pd->stats.secs_rg = 0; + pd->stats.secs_r = 0; + + } else if (strcmp(attr->name, "congestion_off") == 0 + && sscanf(data, "%d", &val) == 1) { + spin_lock(&pd->lock); + pd->write_congestion_off = val; + init_write_congestion_marks(&pd->write_congestion_off, + &pd->write_congestion_on); + spin_unlock(&pd->lock); + + } else if (strcmp(attr->name, "congestion_on") == 0 + && sscanf(data, "%d", &val) == 1) { + spin_lock(&pd->lock); + pd->write_congestion_on = val; + init_write_congestion_marks(&pd->write_congestion_off, + &pd->write_congestion_on); + spin_unlock(&pd->lock); + } + return len; +} + +static const struct sysfs_ops kobj_pkt_ops = { + .show = kobj_pkt_show, + .store = kobj_pkt_store +}; +static struct kobj_type kobj_pkt_type_stat = { + .release = pkt_kobj_release, + .sysfs_ops = &kobj_pkt_ops, + .default_attrs = kobj_pkt_attrs_stat +}; +static struct kobj_type kobj_pkt_type_wqueue = { + .release = pkt_kobj_release, + .sysfs_ops = &kobj_pkt_ops, + .default_attrs = kobj_pkt_attrs_wqueue +}; + +static void pkt_sysfs_dev_new(struct pktcdvd_device *pd) +{ + if (class_pktcdvd) { + pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL, + "%s", pd->name); + if (IS_ERR(pd->dev)) + pd->dev = NULL; + } + if (pd->dev) { + pd->kobj_stat = pkt_kobj_create(pd, "stat", + &pd->dev->kobj, + &kobj_pkt_type_stat); + pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue", + &pd->dev->kobj, + &kobj_pkt_type_wqueue); + } +} + +static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd) +{ + pkt_kobj_remove(pd->kobj_stat); + pkt_kobj_remove(pd->kobj_wqueue); + if (class_pktcdvd) + device_unregister(pd->dev); +} + + +/******************************************************************** + /sys/class/pktcdvd/ + add map block device + remove unmap packet dev + device_map show mappings + *******************************************************************/ + +static void class_pktcdvd_release(struct class *cls) +{ + kfree(cls); +} +static ssize_t class_pktcdvd_show_map(struct class *c, + struct class_attribute *attr, + char *data) +{ + int n = 0; + int idx; + mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); + for (idx = 0; idx < MAX_WRITERS; idx++) { + struct pktcdvd_device *pd = pkt_devs[idx]; + if (!pd) + continue; + n += sprintf(data+n, "%s %u:%u %u:%u\n", + pd->name, + MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev), + MAJOR(pd->bdev->bd_dev), + MINOR(pd->bdev->bd_dev)); + } + mutex_unlock(&ctl_mutex); + return n; +} + +static ssize_t class_pktcdvd_store_add(struct class *c, + struct class_attribute *attr, + const char *buf, + size_t count) +{ + unsigned int major, minor; + + if (sscanf(buf, "%u:%u", &major, &minor) == 2) { + /* pkt_setup_dev() expects caller to hold reference to self */ + if (!try_module_get(THIS_MODULE)) + return -ENODEV; + + pkt_setup_dev(MKDEV(major, minor), NULL); + + module_put(THIS_MODULE); + + return count; + } + + return -EINVAL; +} + +static ssize_t class_pktcdvd_store_remove(struct class *c, + struct class_attribute *attr, + const char *buf, + size_t count) +{ + unsigned int major, minor; + if (sscanf(buf, "%u:%u", &major, &minor) == 2) { + pkt_remove_dev(MKDEV(major, minor)); + return count; + } + return -EINVAL; +} + +static struct class_attribute class_pktcdvd_attrs[] = { + __ATTR(add, 0200, NULL, class_pktcdvd_store_add), + __ATTR(remove, 0200, NULL, class_pktcdvd_store_remove), + __ATTR(device_map, 0444, class_pktcdvd_show_map, NULL), + __ATTR_NULL +}; + + +static int pkt_sysfs_init(void) +{ + int ret = 0; + + /* + * create control files in sysfs + * /sys/class/pktcdvd/... + */ + class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL); + if (!class_pktcdvd) + return -ENOMEM; + class_pktcdvd->name = DRIVER_NAME; + class_pktcdvd->owner = THIS_MODULE; + class_pktcdvd->class_release = class_pktcdvd_release; + class_pktcdvd->class_attrs = class_pktcdvd_attrs; + ret = class_register(class_pktcdvd); + if (ret) { + kfree(class_pktcdvd); + class_pktcdvd = NULL; + pr_err("failed to create class pktcdvd\n"); + return ret; + } + return 0; +} + +static void pkt_sysfs_cleanup(void) +{ + if (class_pktcdvd) + class_destroy(class_pktcdvd); + class_pktcdvd = NULL; +} + +/******************************************************************** + entries in debugfs + + /sys/kernel/debug/pktcdvd[0-7]/ + info + + *******************************************************************/ + +static int pkt_debugfs_seq_show(struct seq_file *m, void *p) +{ + return pkt_seq_show(m, p); +} + +static int pkt_debugfs_fops_open(struct inode *inode, struct file *file) +{ + return single_open(file, pkt_debugfs_seq_show, inode->i_private); +} + +static const struct file_operations debug_fops = { + .open = pkt_debugfs_fops_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .owner = THIS_MODULE, +}; + +static void pkt_debugfs_dev_new(struct pktcdvd_device *pd) +{ + if (!pkt_debugfs_root) + return; + pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root); + if (!pd->dfs_d_root) + return; + + 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; + debugfs_remove(pd->dfs_f_info); + debugfs_remove(pd->dfs_d_root); + 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; +} + +/* ----------------------------------------------------------*/ + + +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)) { + pkt_dbg(2, pd, "queue empty\n"); + atomic_set(&pd->iosched.attention, 1); + wake_up(&pd->wqueue); + } +} + +/* + * Allocate a packet_data struct + */ +static struct packet_data *pkt_alloc_packet_data(int frames) +{ + int i; + struct packet_data *pkt; + + pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL); + if (!pkt) + goto no_pkt; + + pkt->frames = frames; + pkt->w_bio = bio_kmalloc(GFP_KERNEL, frames); + if (!pkt->w_bio) + goto no_bio; + + for (i = 0; i < frames / FRAMES_PER_PAGE; i++) { + pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO); + if (!pkt->pages[i]) + goto no_page; + } + + spin_lock_init(&pkt->lock); + bio_list_init(&pkt->orig_bios); + + for (i = 0; i < frames; i++) { + struct bio *bio = bio_kmalloc(GFP_KERNEL, 1); + if (!bio) + goto no_rd_bio; + + pkt->r_bios[i] = bio; + } + + return pkt; + +no_rd_bio: + for (i = 0; i < frames; i++) { + struct bio *bio = pkt->r_bios[i]; + if (bio) + bio_put(bio); + } + +no_page: + for (i = 0; i < frames / FRAMES_PER_PAGE; i++) + if (pkt->pages[i]) + __free_page(pkt->pages[i]); + bio_put(pkt->w_bio); +no_bio: + kfree(pkt); +no_pkt: + return NULL; +} + +/* + * Free a packet_data struct + */ +static void pkt_free_packet_data(struct packet_data *pkt) +{ + int i; + + for (i = 0; i < pkt->frames; i++) { + struct bio *bio = pkt->r_bios[i]; + if (bio) + bio_put(bio); + } + for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++) + __free_page(pkt->pages[i]); + bio_put(pkt->w_bio); + kfree(pkt); +} + +static void pkt_shrink_pktlist(struct pktcdvd_device *pd) +{ + struct packet_data *pkt, *next; + + BUG_ON(!list_empty(&pd->cdrw.pkt_active_list)); + + list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) { + pkt_free_packet_data(pkt); + } + INIT_LIST_HEAD(&pd->cdrw.pkt_free_list); +} + +static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets) +{ + struct packet_data *pkt; + + BUG_ON(!list_empty(&pd->cdrw.pkt_free_list)); + + while (nr_packets > 0) { + pkt = pkt_alloc_packet_data(pd->settings.size >> 2); + if (!pkt) { + pkt_shrink_pktlist(pd); + return 0; + } + pkt->id = nr_packets; + pkt->pd = pd; + list_add(&pkt->list, &pd->cdrw.pkt_free_list); + nr_packets--; + } + return 1; +} + +static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node) +{ + struct rb_node *n = rb_next(&node->rb_node); + if (!n) + return NULL; + return rb_entry(n, struct pkt_rb_node, rb_node); +} + +static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node) +{ + rb_erase(&node->rb_node, &pd->bio_queue); + mempool_free(node, pd->rb_pool); + pd->bio_queue_size--; + BUG_ON(pd->bio_queue_size < 0); +} + +/* + * Find the first node in the pd->bio_queue rb tree with a starting sector >= s. + */ +static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s) +{ + struct rb_node *n = pd->bio_queue.rb_node; + struct rb_node *next; + struct pkt_rb_node *tmp; + + if (!n) { + BUG_ON(pd->bio_queue_size > 0); + return NULL; + } + + for (;;) { + tmp = rb_entry(n, struct pkt_rb_node, rb_node); + if (s <= tmp->bio->bi_iter.bi_sector) + next = n->rb_left; + else + next = n->rb_right; + if (!next) + break; + n = next; + } + + if (s > tmp->bio->bi_iter.bi_sector) { + tmp = pkt_rbtree_next(tmp); + if (!tmp) + return NULL; + } + BUG_ON(s > tmp->bio->bi_iter.bi_sector); + return tmp; +} + +/* + * Insert a node into the pd->bio_queue rb tree. + */ +static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node) +{ + struct rb_node **p = &pd->bio_queue.rb_node; + struct rb_node *parent = NULL; + sector_t s = node->bio->bi_iter.bi_sector; + struct pkt_rb_node *tmp; + + while (*p) { + parent = *p; + tmp = rb_entry(parent, struct pkt_rb_node, rb_node); + if (s < tmp->bio->bi_iter.bi_sector) + p = &(*p)->rb_left; + else + p = &(*p)->rb_right; + } + rb_link_node(&node->rb_node, parent, p); + rb_insert_color(&node->rb_node, &pd->bio_queue); + pd->bio_queue_size++; +} + +/* + * Send a packet_command to the underlying block device and + * wait for completion. + */ +static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc) +{ + struct request_queue *q = bdev_get_queue(pd->bdev); + struct request *rq; + int ret = 0; + + rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ? + WRITE : READ, __GFP_WAIT); + if (IS_ERR(rq)) + return PTR_ERR(rq); + blk_rq_set_block_pc(rq); + + if (cgc->buflen) { + ret = blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, + __GFP_WAIT); + if (ret) + goto out; + } + + rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]); + memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE); + + rq->timeout = 60*HZ; + if (cgc->quiet) + rq->cmd_flags |= REQ_QUIET; + + blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0); + if (rq->errors) + ret = -EIO; +out: + blk_put_request(rq); + return ret; +} + +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"; +} + +/* + * A generic sense dump / resolve mechanism should be implemented across + * all ATAPI + SCSI devices. + */ +static void pkt_dump_sense(struct pktcdvd_device *pd, + struct packet_command *cgc) +{ + struct request_sense *sense = cgc->sense; + + if (sense) + 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)); + else + pkt_err(pd, "%*ph - no sense\n", CDROM_PACKET_SIZE, cgc->cmd); +} + +/* + * flush the drive cache to media + */ +static int pkt_flush_cache(struct pktcdvd_device *pd) +{ + struct packet_command cgc; + + init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE); + cgc.cmd[0] = GPCMD_FLUSH_CACHE; + cgc.quiet = 1; + + /* + * the IMMED bit -- we default to not setting it, although that + * would allow a much faster close, this is safer + */ +#if 0 + cgc.cmd[1] = 1 << 1; +#endif + return pkt_generic_packet(pd, &cgc); +} + +/* + * speed is given as the normal factor, e.g. 4 for 4x + */ +static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd, + unsigned write_speed, unsigned read_speed) +{ + struct packet_command cgc; + struct request_sense sense; + int ret; + + init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE); + cgc.sense = &sense; + cgc.cmd[0] = GPCMD_SET_SPEED; + cgc.cmd[2] = (read_speed >> 8) & 0xff; + cgc.cmd[3] = read_speed & 0xff; + cgc.cmd[4] = (write_speed >> 8) & 0xff; + cgc.cmd[5] = write_speed & 0xff; + + if ((ret = pkt_generic_packet(pd, &cgc))) + pkt_dump_sense(pd, &cgc); + + return ret; +} + +/* + * Queue a bio for processing by the low-level CD device. Must be called + * from process context. + */ +static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio) +{ + spin_lock(&pd->iosched.lock); + if (bio_data_dir(bio) == READ) + bio_list_add(&pd->iosched.read_queue, bio); + else + bio_list_add(&pd->iosched.write_queue, bio); + spin_unlock(&pd->iosched.lock); + + atomic_set(&pd->iosched.attention, 1); + wake_up(&pd->wqueue); +} + +/* + * Process the queued read/write requests. This function handles special + * requirements for CDRW drives: + * - A cache flush command must be inserted before a read request if the + * previous request was a write. + * - Switching between reading and writing is slow, so don't do it more often + * than necessary. + * - Optimize for throughput at the expense of latency. This means that streaming + * writes will never be interrupted by a read, but if the drive has to seek + * before the next write, switch to reading instead if there are any pending + * read requests. + * - Set the read speed according to current usage pattern. When only reading + * from the device, it's best to use the highest possible read speed, but + * when switching often between reading and writing, it's better to have the + * same read and write speeds. + */ +static void pkt_iosched_process_queue(struct pktcdvd_device *pd) +{ + + if (atomic_read(&pd->iosched.attention) == 0) + return; + atomic_set(&pd->iosched.attention, 0); + + for (;;) { + struct bio *bio; + int reads_queued, writes_queued; + + spin_lock(&pd->iosched.lock); + reads_queued = !bio_list_empty(&pd->iosched.read_queue); + writes_queued = !bio_list_empty(&pd->iosched.write_queue); + spin_unlock(&pd->iosched.lock); + + if (!reads_queued && !writes_queued) + break; + + if (pd->iosched.writing) { + int need_write_seek = 1; + spin_lock(&pd->iosched.lock); + bio = bio_list_peek(&pd->iosched.write_queue); + spin_unlock(&pd->iosched.lock); + if (bio && (bio->bi_iter.bi_sector == + pd->iosched.last_write)) + need_write_seek = 0; + if (need_write_seek && reads_queued) { + if (atomic_read(&pd->cdrw.pending_bios) > 0) { + pkt_dbg(2, pd, "write, waiting\n"); + break; + } + pkt_flush_cache(pd); + pd->iosched.writing = 0; + } + } else { + if (!reads_queued && writes_queued) { + if (atomic_read(&pd->cdrw.pending_bios) > 0) { + pkt_dbg(2, pd, "read, waiting\n"); + break; + } + pd->iosched.writing = 1; + } + } + + spin_lock(&pd->iosched.lock); + if (pd->iosched.writing) + bio = bio_list_pop(&pd->iosched.write_queue); + else + bio = bio_list_pop(&pd->iosched.read_queue); + spin_unlock(&pd->iosched.lock); + + if (!bio) + continue; + + if (bio_data_dir(bio) == READ) + pd->iosched.successive_reads += + bio->bi_iter.bi_size >> 10; + else { + pd->iosched.successive_reads = 0; + pd->iosched.last_write = bio_end_sector(bio); + } + if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) { + if (pd->read_speed == pd->write_speed) { + pd->read_speed = MAX_SPEED; + pkt_set_speed(pd, pd->write_speed, pd->read_speed); + } + } else { + if (pd->read_speed != pd->write_speed) { + pd->read_speed = pd->write_speed; + pkt_set_speed(pd, pd->write_speed, pd->read_speed); + } + } + + atomic_inc(&pd->cdrw.pending_bios); + generic_make_request(bio); + } +} + +/* + * Special care is needed if the underlying block device has a small + * max_phys_segments value. + */ +static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q) +{ + if ((pd->settings.size << 9) / CD_FRAMESIZE + <= queue_max_segments(q)) { + /* + * The cdrom device can handle one segment/frame + */ + clear_bit(PACKET_MERGE_SEGS, &pd->flags); + return 0; + } else if ((pd->settings.size << 9) / PAGE_SIZE + <= queue_max_segments(q)) { + /* + * We can handle this case at the expense of some extra memory + * copies during write operations + */ + set_bit(PACKET_MERGE_SEGS, &pd->flags); + return 0; + } else { + pkt_err(pd, "cdrom max_phys_segments too small\n"); + return -EIO; + } +} + +/* + * Copy all data for this packet to pkt->pages[], so that + * a) The number of required segments for the write bio is minimized, which + * is necessary for some scsi controllers. + * b) The data can be used as cache to avoid read requests if we receive a + * new write request for the same zone. + */ +static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec) +{ + int f, p, offs; + + /* Copy all data to pkt->pages[] */ + p = 0; + offs = 0; + for (f = 0; f < pkt->frames; f++) { + if (bvec[f].bv_page != pkt->pages[p]) { + void *vfrom = kmap_atomic(bvec[f].bv_page) + bvec[f].bv_offset; + void *vto = page_address(pkt->pages[p]) + offs; + memcpy(vto, vfrom, CD_FRAMESIZE); + kunmap_atomic(vfrom); + bvec[f].bv_page = pkt->pages[p]; + bvec[f].bv_offset = offs; + } else { + BUG_ON(bvec[f].bv_offset != offs); + } + offs += CD_FRAMESIZE; + if (offs >= PAGE_SIZE) { + offs = 0; + p++; + } + } +} + +static void pkt_end_io_read(struct bio *bio, int err) +{ + struct packet_data *pkt = bio->bi_private; + struct pktcdvd_device *pd = pkt->pd; + BUG_ON(!pd); + + pkt_dbg(2, pd, "bio=%p sec0=%llx sec=%llx err=%d\n", + bio, (unsigned long long)pkt->sector, + (unsigned long long)bio->bi_iter.bi_sector, err); + + if (err) + atomic_inc(&pkt->io_errors); + if (atomic_dec_and_test(&pkt->io_wait)) { + atomic_inc(&pkt->run_sm); + wake_up(&pd->wqueue); + } + pkt_bio_finished(pd); +} + +static void pkt_end_io_packet_write(struct bio *bio, int err) +{ + struct packet_data *pkt = bio->bi_private; + struct pktcdvd_device *pd = pkt->pd; + BUG_ON(!pd); + + pkt_dbg(2, pd, "id=%d, err=%d\n", pkt->id, err); + + pd->stats.pkt_ended++; + + pkt_bio_finished(pd); + atomic_dec(&pkt->io_wait); + atomic_inc(&pkt->run_sm); + wake_up(&pd->wqueue); +} + +/* + * Schedule reads for the holes in a packet + */ +static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt) +{ + int frames_read = 0; + struct bio *bio; + int f; + char written[PACKET_MAX_SIZE]; + + BUG_ON(bio_list_empty(&pkt->orig_bios)); + + atomic_set(&pkt->io_wait, 0); + atomic_set(&pkt->io_errors, 0); + + /* + * Figure out which frames we need to read before we can write. + */ + memset(written, 0, sizeof(written)); + spin_lock(&pkt->lock); + bio_list_for_each(bio, &pkt->orig_bios) { + int first_frame = (bio->bi_iter.bi_sector - pkt->sector) / + (CD_FRAMESIZE >> 9); + int num_frames = bio->bi_iter.bi_size / CD_FRAMESIZE; + pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9); + BUG_ON(first_frame < 0); + BUG_ON(first_frame + num_frames > pkt->frames); + for (f = first_frame; f < first_frame + num_frames; f++) + written[f] = 1; + } + spin_unlock(&pkt->lock); + + if (pkt->cache_valid) { + pkt_dbg(2, pd, "zone %llx cached\n", + (unsigned long long)pkt->sector); + goto out_account; + } + + /* + * Schedule reads for missing parts of the packet. + */ + for (f = 0; f < pkt->frames; f++) { + int p, offset; + + if (written[f]) + continue; + + bio = pkt->r_bios[f]; + bio_reset(bio); + bio->bi_iter.bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9); + bio->bi_bdev = pd->bdev; + bio->bi_end_io = pkt_end_io_read; + bio->bi_private = pkt; + + p = (f * CD_FRAMESIZE) / PAGE_SIZE; + offset = (f * CD_FRAMESIZE) % PAGE_SIZE; + pkt_dbg(2, pd, "Adding frame %d, page:%p offs:%d\n", + f, pkt->pages[p], offset); + if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset)) + BUG(); + + atomic_inc(&pkt->io_wait); + bio->bi_rw = READ; + pkt_queue_bio(pd, bio); + frames_read++; + } + +out_account: + pkt_dbg(2, pd, "need %d frames for zone %llx\n", + frames_read, (unsigned long long)pkt->sector); + pd->stats.pkt_started++; + pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9); +} + +/* + * Find a packet matching zone, or the least recently used packet if + * there is no match. + */ +static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone) +{ + struct packet_data *pkt; + + list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) { + if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) { + list_del_init(&pkt->list); + if (pkt->sector != zone) + pkt->cache_valid = 0; + return pkt; + } + } + BUG(); + return NULL; +} + +static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt) +{ + if (pkt->cache_valid) { + list_add(&pkt->list, &pd->cdrw.pkt_free_list); + } else { + list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list); + } +} + +/* + * recover a failed write, query for relocation if possible + * + * returns 1 if recovery is possible, or 0 if not + * + */ +static int pkt_start_recovery(struct packet_data *pkt) +{ + /* + * FIXME. We need help from the file system to implement + * recovery handling. + */ + return 0; +#if 0 + struct request *rq = pkt->rq; + struct pktcdvd_device *pd = rq->rq_disk->private_data; + struct block_device *pkt_bdev; + struct super_block *sb = NULL; + unsigned long old_block, new_block; + sector_t new_sector; + + pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev)); + if (pkt_bdev) { + sb = get_super(pkt_bdev); + bdput(pkt_bdev); + } + + if (!sb) + return 0; + + if (!sb->s_op->relocate_blocks) + goto out; + + old_block = pkt->sector / (CD_FRAMESIZE >> 9); + if (sb->s_op->relocate_blocks(sb, old_block, &new_block)) + goto out; + + new_sector = new_block * (CD_FRAMESIZE >> 9); + pkt->sector = new_sector; + + bio_reset(pkt->bio); + pkt->bio->bi_bdev = pd->bdev; + pkt->bio->bi_rw = REQ_WRITE; + pkt->bio->bi_iter.bi_sector = new_sector; + pkt->bio->bi_iter.bi_size = pkt->frames * CD_FRAMESIZE; + pkt->bio->bi_vcnt = pkt->frames; + + pkt->bio->bi_end_io = pkt_end_io_packet_write; + pkt->bio->bi_private = pkt; + + drop_super(sb); + return 1; + +out: + drop_super(sb); + return 0; +#endif +} + +static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state) +{ +#if PACKET_DEBUG > 1 + static const char *state_name[] = { + "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED" + }; + enum packet_data_state old_state = pkt->state; + pkt_dbg(2, pd, "pkt %2d : s=%6llx %s -> %s\n", + pkt->id, (unsigned long long)pkt->sector, + state_name[old_state], state_name[state]); +#endif + pkt->state = state; +} + +/* + * Scan the work queue to see if we can start a new packet. + * returns non-zero if any work was done. + */ +static int pkt_handle_queue(struct pktcdvd_device *pd) +{ + struct packet_data *pkt, *p; + struct bio *bio = NULL; + sector_t zone = 0; /* Suppress gcc warning */ + struct pkt_rb_node *node, *first_node; + struct rb_node *n; + int wakeup; + + atomic_set(&pd->scan_queue, 0); + + if (list_empty(&pd->cdrw.pkt_free_list)) { + pkt_dbg(2, pd, "no pkt\n"); + return 0; + } + + /* + * Try to find a zone we are not already working on. + */ + spin_lock(&pd->lock); + first_node = pkt_rbtree_find(pd, pd->current_sector); + if (!first_node) { + n = rb_first(&pd->bio_queue); + if (n) + first_node = rb_entry(n, struct pkt_rb_node, rb_node); + } + node = first_node; + while (node) { + bio = node->bio; + zone = get_zone(bio->bi_iter.bi_sector, pd); + list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) { + if (p->sector == zone) { + bio = NULL; + goto try_next_bio; + } + } + break; +try_next_bio: + node = pkt_rbtree_next(node); + if (!node) { + n = rb_first(&pd->bio_queue); + if (n) + node = rb_entry(n, struct pkt_rb_node, rb_node); + } + if (node == first_node) + node = NULL; + } + spin_unlock(&pd->lock); + if (!bio) { + pkt_dbg(2, pd, "no bio\n"); + return 0; + } + + pkt = pkt_get_packet_data(pd, zone); + + pd->current_sector = zone + pd->settings.size; + pkt->sector = zone; + BUG_ON(pkt->frames != pd->settings.size >> 2); + pkt->write_size = 0; + + /* + * Scan work queue for bios in the same zone and link them + * to this packet. + */ + spin_lock(&pd->lock); + pkt_dbg(2, pd, "looking for zone %llx\n", (unsigned long long)zone); + while ((node = pkt_rbtree_find(pd, zone)) != NULL) { + bio = node->bio; + 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) + break; + pkt_rbtree_erase(pd, node); + spin_lock(&pkt->lock); + bio_list_add(&pkt->orig_bios, bio); + pkt->write_size += bio->bi_iter.bi_size / CD_FRAMESIZE; + spin_unlock(&pkt->lock); + } + /* check write congestion marks, and if bio_queue_size is + below, wake up any waiters */ + wakeup = (pd->write_congestion_on > 0 + && pd->bio_queue_size <= pd->write_congestion_off); + spin_unlock(&pd->lock); + if (wakeup) { + clear_bdi_congested(&pd->disk->queue->backing_dev_info, + BLK_RW_ASYNC); + } + + pkt->sleep_time = max(PACKET_WAIT_TIME, 1); + pkt_set_state(pkt, PACKET_WAITING_STATE); + atomic_set(&pkt->run_sm, 1); + + spin_lock(&pd->cdrw.active_list_lock); + list_add(&pkt->list, &pd->cdrw.pkt_active_list); + spin_unlock(&pd->cdrw.active_list_lock); + + return 1; +} + +/* + * Assemble a bio to write one packet and queue the bio for processing + * by the underlying block device. + */ +static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt) +{ + int f; + struct bio_vec *bvec = pkt->w_bio->bi_io_vec; + + bio_reset(pkt->w_bio); + pkt->w_bio->bi_iter.bi_sector = pkt->sector; + pkt->w_bio->bi_bdev = pd->bdev; + pkt->w_bio->bi_end_io = pkt_end_io_packet_write; + pkt->w_bio->bi_private = pkt; + + /* XXX: locking? */ + for (f = 0; f < pkt->frames; f++) { + bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE]; + bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE; + if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset)) + BUG(); + } + pkt_dbg(2, pd, "vcnt=%d\n", pkt->w_bio->bi_vcnt); + + /* + * Fill-in bvec with data from orig_bios. + */ + spin_lock(&pkt->lock); + bio_copy_data(pkt->w_bio, pkt->orig_bios.head); + + pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE); + spin_unlock(&pkt->lock); + + pkt_dbg(2, pd, "Writing %d frames for zone %llx\n", + pkt->write_size, (unsigned long long)pkt->sector); + + if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) { + pkt_make_local_copy(pkt, bvec); + pkt->cache_valid = 1; + } else { + pkt->cache_valid = 0; + } + + /* Start the write request */ + atomic_set(&pkt->io_wait, 1); + pkt->w_bio->bi_rw = WRITE; + pkt_queue_bio(pd, pkt->w_bio); +} + +static void pkt_finish_packet(struct packet_data *pkt, int uptodate) +{ + struct bio *bio; + + if (!uptodate) + pkt->cache_valid = 0; + + /* Finish all bios corresponding to this packet */ + while ((bio = bio_list_pop(&pkt->orig_bios))) + bio_endio(bio, uptodate ? 0 : -EIO); +} + +static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt) +{ + int uptodate; + + pkt_dbg(2, pd, "pkt %d\n", pkt->id); + + for (;;) { + switch (pkt->state) { + case PACKET_WAITING_STATE: + if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0)) + return; + + pkt->sleep_time = 0; + pkt_gather_data(pd, pkt); + pkt_set_state(pkt, PACKET_READ_WAIT_STATE); + break; + + case PACKET_READ_WAIT_STATE: + if (atomic_read(&pkt->io_wait) > 0) + return; + + if (atomic_read(&pkt->io_errors) > 0) { + pkt_set_state(pkt, PACKET_RECOVERY_STATE); + } else { + pkt_start_write(pd, pkt); + } + break; + + case PACKET_WRITE_WAIT_STATE: + if (atomic_read(&pkt->io_wait) > 0) + return; + + if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) { + pkt_set_state(pkt, PACKET_FINISHED_STATE); + } else { + pkt_set_state(pkt, PACKET_RECOVERY_STATE); + } + break; + + case PACKET_RECOVERY_STATE: + if (pkt_start_recovery(pkt)) { + pkt_start_write(pd, pkt); + } else { + pkt_dbg(2, pd, "No recovery possible\n"); + pkt_set_state(pkt, PACKET_FINISHED_STATE); + } + break; + + case PACKET_FINISHED_STATE: + uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags); + pkt_finish_packet(pkt, uptodate); + return; + + default: + BUG(); + break; + } + } +} + +static void pkt_handle_packets(struct pktcdvd_device *pd) +{ + struct packet_data *pkt, *next; + + /* + * Run state machine for active packets + */ + list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) { + if (atomic_read(&pkt->run_sm) > 0) { + atomic_set(&pkt->run_sm, 0); + pkt_run_state_machine(pd, pkt); + } + } + + /* + * Move no longer active packets to the free list + */ + spin_lock(&pd->cdrw.active_list_lock); + list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) { + if (pkt->state == PACKET_FINISHED_STATE) { + list_del(&pkt->list); + pkt_put_packet_data(pd, pkt); + pkt_set_state(pkt, PACKET_IDLE_STATE); + atomic_set(&pd->scan_queue, 1); + } + } + spin_unlock(&pd->cdrw.active_list_lock); +} + +static void pkt_count_states(struct pktcdvd_device *pd, int *states) +{ + struct packet_data *pkt; + int i; + + for (i = 0; i < PACKET_NUM_STATES; i++) + states[i] = 0; + + spin_lock(&pd->cdrw.active_list_lock); + list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) { + states[pkt->state]++; + } + spin_unlock(&pd->cdrw.active_list_lock); +} + +/* + * kcdrwd is woken up when writes have been queued for one of our + * registered devices + */ +static int kcdrwd(void *foobar) +{ + struct pktcdvd_device *pd = foobar; + struct packet_data *pkt; + long min_sleep_time, residue; + + set_user_nice(current, MIN_NICE); + set_freezable(); + + for (;;) { + DECLARE_WAITQUEUE(wait, current); + + /* + * Wait until there is something to do + */ + add_wait_queue(&pd->wqueue, &wait); + for (;;) { + set_current_state(TASK_INTERRUPTIBLE); + + /* Check if we need to run pkt_handle_queue */ + if (atomic_read(&pd->scan_queue) > 0) + goto work_to_do; + + /* Check if we need to run the state machine for some packet */ + list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) { + if (atomic_read(&pkt->run_sm) > 0) + goto work_to_do; + } + + /* Check if we need to process the iosched queues */ + if (atomic_read(&pd->iosched.attention) != 0) + goto work_to_do; + + /* Otherwise, go to sleep */ + if (PACKET_DEBUG > 1) { + int states[PACKET_NUM_STATES]; + pkt_count_states(pd, states); + pkt_dbg(2, pd, "i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n", + states[0], states[1], states[2], + states[3], states[4], states[5]); + } + + min_sleep_time = MAX_SCHEDULE_TIMEOUT; + list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) { + if (pkt->sleep_time && pkt->sleep_time < min_sleep_time) + min_sleep_time = pkt->sleep_time; + } + + pkt_dbg(2, pd, "sleeping\n"); + residue = schedule_timeout(min_sleep_time); + pkt_dbg(2, pd, "wake up\n"); + + /* make swsusp happy with our thread */ + try_to_freeze(); + + list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) { + if (!pkt->sleep_time) + continue; + pkt->sleep_time -= min_sleep_time - residue; + if (pkt->sleep_time <= 0) { + pkt->sleep_time = 0; + atomic_inc(&pkt->run_sm); + } + } + + if (kthread_should_stop()) + break; + } +work_to_do: + set_current_state(TASK_RUNNING); + remove_wait_queue(&pd->wqueue, &wait); + + if (kthread_should_stop()) + break; + + /* + * if pkt_handle_queue returns true, we can queue + * another request. + */ + while (pkt_handle_queue(pd)) + ; + + /* + * Handle packet state machine + */ + pkt_handle_packets(pd); + + /* + * Handle iosched queues + */ + pkt_iosched_process_queue(pd); + } + + return 0; +} + +static void pkt_print_settings(struct pktcdvd_device *pd) +{ + 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'); +} + +static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control) +{ + memset(cgc->cmd, 0, sizeof(cgc->cmd)); + + cgc->cmd[0] = GPCMD_MODE_SENSE_10; + cgc->cmd[2] = page_code | (page_control << 6); + cgc->cmd[7] = cgc->buflen >> 8; + cgc->cmd[8] = cgc->buflen & 0xff; + cgc->data_direction = CGC_DATA_READ; + return pkt_generic_packet(pd, cgc); +} + +static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc) +{ + memset(cgc->cmd, 0, sizeof(cgc->cmd)); + memset(cgc->buffer, 0, 2); + cgc->cmd[0] = GPCMD_MODE_SELECT_10; + cgc->cmd[1] = 0x10; /* PF */ + cgc->cmd[7] = cgc->buflen >> 8; + cgc->cmd[8] = cgc->buflen & 0xff; + cgc->data_direction = CGC_DATA_WRITE; + return pkt_generic_packet(pd, cgc); +} + +static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di) +{ + struct packet_command cgc; + int ret; + + /* set up command and get the disc info */ + init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ); + cgc.cmd[0] = GPCMD_READ_DISC_INFO; + cgc.cmd[8] = cgc.buflen = 2; + cgc.quiet = 1; + + if ((ret = pkt_generic_packet(pd, &cgc))) + return ret; + + /* not all drives have the same disc_info length, so requeue + * packet with the length the drive tells us it can supply + */ + cgc.buflen = be16_to_cpu(di->disc_information_length) + + sizeof(di->disc_information_length); + + if (cgc.buflen > sizeof(disc_information)) + cgc.buflen = sizeof(disc_information); + + cgc.cmd[8] = cgc.buflen; + return pkt_generic_packet(pd, &cgc); +} + +static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti) +{ + struct packet_command cgc; + int ret; + + init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ); + cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO; + cgc.cmd[1] = type & 3; + cgc.cmd[4] = (track & 0xff00) >> 8; + cgc.cmd[5] = track & 0xff; + cgc.cmd[8] = 8; + cgc.quiet = 1; + + if ((ret = pkt_generic_packet(pd, &cgc))) + return ret; + + cgc.buflen = be16_to_cpu(ti->track_information_length) + + sizeof(ti->track_information_length); + + if (cgc.buflen > sizeof(track_information)) + cgc.buflen = sizeof(track_information); + + cgc.cmd[8] = cgc.buflen; + return pkt_generic_packet(pd, &cgc); +} + +static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd, + long *last_written) +{ + disc_information di; + track_information ti; + __u32 last_track; + int ret = -1; + + if ((ret = pkt_get_disc_info(pd, &di))) + return ret; + + last_track = (di.last_track_msb << 8) | di.last_track_lsb; + if ((ret = pkt_get_track_info(pd, last_track, 1, &ti))) + return ret; + + /* if this track is blank, try the previous. */ + if (ti.blank) { + last_track--; + if ((ret = pkt_get_track_info(pd, last_track, 1, &ti))) + return ret; + } + + /* if last recorded field is valid, return it. */ + if (ti.lra_v) { + *last_written = be32_to_cpu(ti.last_rec_address); + } else { + /* make it up instead */ + *last_written = be32_to_cpu(ti.track_start) + + be32_to_cpu(ti.track_size); + if (ti.free_blocks) + *last_written -= (be32_to_cpu(ti.free_blocks) + 7); + } + return 0; +} + +/* + * write mode select package based on pd->settings + */ +static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd) +{ + struct packet_command cgc; + struct request_sense sense; + write_param_page *wp; + char buffer[128]; + int ret, size; + + /* doesn't apply to DVD+RW or DVD-RAM */ + if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12)) + return 0; + + memset(buffer, 0, sizeof(buffer)); + init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ); + cgc.sense = &sense; + if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) { + pkt_dump_sense(pd, &cgc); + return ret; + } + + size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff)); + pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff); + if (size > sizeof(buffer)) + size = sizeof(buffer); + + /* + * now get it all + */ + init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ); + cgc.sense = &sense; + if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) { + pkt_dump_sense(pd, &cgc); + return ret; + } + + /* + * write page is offset header + block descriptor length + */ + wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset]; + + wp->fp = pd->settings.fp; + wp->track_mode = pd->settings.track_mode; + wp->write_type = pd->settings.write_type; + wp->data_block_type = pd->settings.block_mode; + + wp->multi_session = 0; + +#ifdef PACKET_USE_LS + wp->link_size = 7; + wp->ls_v = 1; +#endif + + if (wp->data_block_type == PACKET_BLOCK_MODE1) { + wp->session_format = 0; + wp->subhdr2 = 0x20; + } else if (wp->data_block_type == PACKET_BLOCK_MODE2) { + wp->session_format = 0x20; + wp->subhdr2 = 8; +#if 0 + wp->mcn[0] = 0x80; + memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1); +#endif + } else { + /* + * paranoia + */ + pkt_err(pd, "write mode wrong %d\n", wp->data_block_type); + return 1; + } + wp->packet_size = cpu_to_be32(pd->settings.size >> 2); + + cgc.buflen = cgc.cmd[8] = size; + if ((ret = pkt_mode_select(pd, &cgc))) { + pkt_dump_sense(pd, &cgc); + return ret; + } + + pkt_print_settings(pd); + return 0; +} + +/* + * 1 -- we can write to this track, 0 -- we can't + */ +static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti) +{ + switch (pd->mmc3_profile) { + case 0x1a: /* DVD+RW */ + case 0x12: /* DVD-RAM */ + /* The track is always writable on DVD+RW/DVD-RAM */ + return 1; + default: + break; + } + + if (!ti->packet || !ti->fp) + return 0; + + /* + * "good" settings as per Mt Fuji. + */ + if (ti->rt == 0 && ti->blank == 0) + return 1; + + if (ti->rt == 0 && ti->blank == 1) + return 1; + + if (ti->rt == 1 && ti->blank == 0) + return 1; + + pkt_err(pd, "bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet); + return 0; +} + +/* + * 1 -- we can write to this disc, 0 -- we can't + */ +static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di) +{ + switch (pd->mmc3_profile) { + case 0x0a: /* CD-RW */ + case 0xffff: /* MMC3 not supported */ + break; + case 0x1a: /* DVD+RW */ + case 0x13: /* DVD-RW */ + case 0x12: /* DVD-RAM */ + return 1; + default: + pkt_dbg(2, pd, "Wrong disc profile (%x)\n", + pd->mmc3_profile); + return 0; + } + + /* + * for disc type 0xff we should probably reserve a new track. + * but i'm not sure, should we leave this to user apps? probably. + */ + if (di->disc_type == 0xff) { + pkt_notice(pd, "unknown disc - no track?\n"); + return 0; + } + + if (di->disc_type != 0x20 && di->disc_type != 0) { + pkt_err(pd, "wrong disc type (%x)\n", di->disc_type); + return 0; + } + + if (di->erasable == 0) { + pkt_notice(pd, "disc not erasable\n"); + return 0; + } + + if (di->border_status == PACKET_SESSION_RESERVED) { + pkt_err(pd, "can't write to last track (reserved)\n"); + return 0; + } + + return 1; +} + +static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd) +{ + struct packet_command cgc; + unsigned char buf[12]; + disc_information di; + track_information ti; + int ret, track; + + init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ); + cgc.cmd[0] = GPCMD_GET_CONFIGURATION; + cgc.cmd[8] = 8; + ret = pkt_generic_packet(pd, &cgc); + pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7]; + + memset(&di, 0, sizeof(disc_information)); + memset(&ti, 0, sizeof(track_information)); + + if ((ret = pkt_get_disc_info(pd, &di))) { + pkt_err(pd, "failed get_disc\n"); + return ret; + } + + if (!pkt_writable_disc(pd, &di)) + return -EROFS; + + pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR; + + track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */ + if ((ret = pkt_get_track_info(pd, track, 1, &ti))) { + pkt_err(pd, "failed get_track\n"); + return ret; + } + + if (!pkt_writable_track(pd, &ti)) { + pkt_err(pd, "can't write to this track\n"); + return -EROFS; + } + + /* + * we keep packet size in 512 byte units, makes it easier to + * deal with request calculations. + */ + pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2; + if (pd->settings.size == 0) { + pkt_notice(pd, "detected zero packet size!\n"); + return -ENXIO; + } + if (pd->settings.size > PACKET_MAX_SECTORS) { + pkt_err(pd, "packet size is too big\n"); + return -EROFS; + } + pd->settings.fp = ti.fp; + pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1); + + if (ti.nwa_v) { + pd->nwa = be32_to_cpu(ti.next_writable); + set_bit(PACKET_NWA_VALID, &pd->flags); + } + + /* + * in theory we could use lra on -RW media as well and just zero + * blocks that haven't been written yet, but in practice that + * is just a no-go. we'll use that for -R, naturally. + */ + if (ti.lra_v) { + pd->lra = be32_to_cpu(ti.last_rec_address); + set_bit(PACKET_LRA_VALID, &pd->flags); + } else { + pd->lra = 0xffffffff; + set_bit(PACKET_LRA_VALID, &pd->flags); + } + + /* + * fine for now + */ + pd->settings.link_loss = 7; + pd->settings.write_type = 0; /* packet */ + pd->settings.track_mode = ti.track_mode; + + /* + * mode1 or mode2 disc + */ + switch (ti.data_mode) { + case PACKET_MODE1: + pd->settings.block_mode = PACKET_BLOCK_MODE1; + break; + case PACKET_MODE2: + pd->settings.block_mode = PACKET_BLOCK_MODE2; + break; + default: + pkt_err(pd, "unknown data mode\n"); + return -EROFS; + } + return 0; +} + +/* + * enable/disable write caching on drive + */ +static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd, + int set) +{ + struct packet_command cgc; + struct request_sense sense; + unsigned char buf[64]; + int ret; + + init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ); + cgc.sense = &sense; + cgc.buflen = pd->mode_offset + 12; + + /* + * caching mode page might not be there, so quiet this command + */ + cgc.quiet = 1; + + if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0))) + return ret; + + buf[pd->mode_offset + 10] |= (!!set << 2); + + cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff)); + ret = pkt_mode_select(pd, &cgc); + if (ret) { + pkt_err(pd, "write caching control failed\n"); + pkt_dump_sense(pd, &cgc); + } else if (!ret && set) + pkt_notice(pd, "enabled write caching\n"); + return ret; +} + +static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag) +{ + struct packet_command cgc; + + init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE); + cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL; + cgc.cmd[4] = lockflag ? 1 : 0; + return pkt_generic_packet(pd, &cgc); +} + +/* + * Returns drive maximum write speed + */ +static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd, + unsigned *write_speed) +{ + struct packet_command cgc; + struct request_sense sense; + unsigned char buf[256+18]; + unsigned char *cap_buf; + int ret, offset; + + cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset]; + init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN); + cgc.sense = &sense; + + ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0); + if (ret) { + cgc.buflen = pd->mode_offset + cap_buf[1] + 2 + + sizeof(struct mode_page_header); + ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0); + if (ret) { + pkt_dump_sense(pd, &cgc); + return ret; + } + } + + offset = 20; /* Obsoleted field, used by older drives */ + if (cap_buf[1] >= 28) + offset = 28; /* Current write speed selected */ + if (cap_buf[1] >= 30) { + /* If the drive reports at least one "Logical Unit Write + * Speed Performance Descriptor Block", use the information + * in the first block. (contains the highest speed) + */ + int num_spdb = (cap_buf[30] << 8) + cap_buf[31]; + if (num_spdb > 0) + offset = 34; + } + + *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1]; + return 0; +} + +/* These tables from cdrecord - I don't have orange book */ +/* standard speed CD-RW (1-4x) */ +static char clv_to_speed[16] = { + /* 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 */ + 0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 +}; +/* high speed CD-RW (-10x) */ +static char hs_clv_to_speed[16] = { + /* 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 */ + 0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 +}; +/* ultra high speed CD-RW */ +static char us_clv_to_speed[16] = { + /* 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 */ + 0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0 +}; + +/* + * reads the maximum media speed from ATIP + */ +static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd, + unsigned *speed) +{ + struct packet_command cgc; + struct request_sense sense; + unsigned char buf[64]; + unsigned int size, st, sp; + int ret; + + init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ); + cgc.sense = &sense; + cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP; + cgc.cmd[1] = 2; + cgc.cmd[2] = 4; /* READ ATIP */ + cgc.cmd[8] = 2; + ret = pkt_generic_packet(pd, &cgc); + if (ret) { + pkt_dump_sense(pd, &cgc); + return ret; + } + size = ((unsigned int) buf[0]<<8) + buf[1] + 2; + if (size > sizeof(buf)) + size = sizeof(buf); + + init_cdrom_command(&cgc, buf, size, CGC_DATA_READ); + cgc.sense = &sense; + cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP; + cgc.cmd[1] = 2; + cgc.cmd[2] = 4; + cgc.cmd[8] = size; + ret = pkt_generic_packet(pd, &cgc); + if (ret) { + pkt_dump_sense(pd, &cgc); + return ret; + } + + if (!(buf[6] & 0x40)) { + pkt_notice(pd, "disc type is not CD-RW\n"); + return 1; + } + if (!(buf[6] & 0x4)) { + pkt_notice(pd, "A1 values on media are not valid, maybe not CDRW?\n"); + return 1; + } + + st = (buf[6] >> 3) & 0x7; /* disc sub-type */ + + sp = buf[16] & 0xf; /* max speed from ATIP A1 field */ + + /* Info from cdrecord */ + switch (st) { + case 0: /* standard speed */ + *speed = clv_to_speed[sp]; + break; + case 1: /* high speed */ + *speed = hs_clv_to_speed[sp]; + break; + case 2: /* ultra high speed */ + *speed = us_clv_to_speed[sp]; + break; + default: + pkt_notice(pd, "unknown disc sub-type %d\n", st); + return 1; + } + if (*speed) { + pkt_info(pd, "maximum media speed: %d\n", *speed); + return 0; + } else { + pkt_notice(pd, "unknown speed %d for sub-type %d\n", sp, st); + return 1; + } +} + +static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd) +{ + struct packet_command cgc; + struct request_sense sense; + int ret; + + pkt_dbg(2, pd, "Performing OPC\n"); + + init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE); + cgc.sense = &sense; + cgc.timeout = 60*HZ; + cgc.cmd[0] = GPCMD_SEND_OPC; + cgc.cmd[1] = 1; + if ((ret = pkt_generic_packet(pd, &cgc))) + pkt_dump_sense(pd, &cgc); + return ret; +} + +static int pkt_open_write(struct pktcdvd_device *pd) +{ + int ret; + unsigned int write_speed, media_write_speed, read_speed; + + if ((ret = pkt_probe_settings(pd))) { + pkt_dbg(2, pd, "failed probe\n"); + return ret; + } + + if ((ret = pkt_set_write_settings(pd))) { + pkt_dbg(1, pd, "failed saving write settings\n"); + 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 */ + pkt_dbg(1, pd, "write speed %ukB/s\n", write_speed); + break; + default: + if ((ret = pkt_media_speed(pd, &media_write_speed))) + media_write_speed = 16; + write_speed = min(write_speed, media_write_speed * 177); + pkt_dbg(1, pd, "write speed %ux\n", write_speed / 176); + break; + } + read_speed = write_speed; + + if ((ret = pkt_set_speed(pd, write_speed, read_speed))) { + pkt_dbg(1, pd, "couldn't set write speed\n"); + return -EIO; + } + pd->write_speed = write_speed; + pd->read_speed = read_speed; + + if ((ret = pkt_perform_opc(pd))) { + pkt_dbg(1, pd, "Optimum Power Calibration failed\n"); + } + + return 0; +} + +/* + * called at open time. + */ +static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write) +{ + int ret; + long lba; + struct request_queue *q; + + /* + * We need to re-open the cdrom device without O_NONBLOCK to be able + * to read/write from/to it. It is already opened in O_NONBLOCK mode + * so bdget() can't fail. + */ + bdget(pd->bdev->bd_dev); + if ((ret = blkdev_get(pd->bdev, FMODE_READ | FMODE_EXCL, pd))) + goto out; + + if ((ret = pkt_get_last_written(pd, &lba))) { + pkt_err(pd, "pkt_get_last_written failed\n"); + goto out_putdev; + } + + set_capacity(pd->disk, lba << 2); + set_capacity(pd->bdev->bd_disk, lba << 2); + bd_set_size(pd->bdev, (loff_t)lba << 11); + + q = bdev_get_queue(pd->bdev); + if (write) { + if ((ret = pkt_open_write(pd))) + goto out_putdev; + /* + * Some CDRW drives can not handle writes larger than one packet, + * even if the size is a multiple of the packet size. + */ + spin_lock_irq(q->queue_lock); + blk_queue_max_hw_sectors(q, pd->settings.size); + spin_unlock_irq(q->queue_lock); + set_bit(PACKET_WRITABLE, &pd->flags); + } else { + pkt_set_speed(pd, MAX_SPEED, MAX_SPEED); + clear_bit(PACKET_WRITABLE, &pd->flags); + } + + if ((ret = pkt_set_segment_merging(pd, q))) + goto out_putdev; + + if (write) { + if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) { + pkt_err(pd, "not enough memory for buffers\n"); + ret = -ENOMEM; + goto out_putdev; + } + pkt_info(pd, "%lukB available on disc\n", lba << 1); + } + + return 0; + +out_putdev: + blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL); +out: + return ret; +} + +/* + * called when the device is closed. makes sure that the device flushes + * the internal cache before we close. + */ +static void pkt_release_dev(struct pktcdvd_device *pd, int flush) +{ + if (flush && pkt_flush_cache(pd)) + pkt_dbg(1, pd, "not flushing cache\n"); + + pkt_lock_door(pd, 0); + + pkt_set_speed(pd, MAX_SPEED, MAX_SPEED); + blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL); + + pkt_shrink_pktlist(pd); +} + +static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor) +{ + if (dev_minor >= MAX_WRITERS) + return NULL; + return pkt_devs[dev_minor]; +} + +static int pkt_open(struct block_device *bdev, fmode_t mode) +{ + struct pktcdvd_device *pd = NULL; + int ret; + + mutex_lock(&pktcdvd_mutex); + mutex_lock(&ctl_mutex); + pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev)); + if (!pd) { + ret = -ENODEV; + goto out; + } + BUG_ON(pd->refcnt < 0); + + pd->refcnt++; + if (pd->refcnt > 1) { + if ((mode & FMODE_WRITE) && + !test_bit(PACKET_WRITABLE, &pd->flags)) { + ret = -EBUSY; + goto out_dec; + } + } else { + ret = pkt_open_dev(pd, mode & FMODE_WRITE); + if (ret) + goto out_dec; + /* + * needed here as well, since ext2 (among others) may change + * the blocksize at mount time + */ + set_blocksize(bdev, CD_FRAMESIZE); + } + + mutex_unlock(&ctl_mutex); + mutex_unlock(&pktcdvd_mutex); + return 0; + +out_dec: + pd->refcnt--; +out: + mutex_unlock(&ctl_mutex); + mutex_unlock(&pktcdvd_mutex); + return ret; +} + +static void pkt_close(struct gendisk *disk, fmode_t mode) +{ + struct pktcdvd_device *pd = disk->private_data; + + mutex_lock(&pktcdvd_mutex); + mutex_lock(&ctl_mutex); + pd->refcnt--; + BUG_ON(pd->refcnt < 0); + if (pd->refcnt == 0) { + int flush = test_bit(PACKET_WRITABLE, &pd->flags); + pkt_release_dev(pd, flush); + } + mutex_unlock(&ctl_mutex); + mutex_unlock(&pktcdvd_mutex); +} + + +static void pkt_end_io_read_cloned(struct bio *bio, int err) +{ + struct packet_stacked_data *psd = bio->bi_private; + struct pktcdvd_device *pd = psd->pd; + + bio_put(bio); + bio_endio(psd->bio, err); + mempool_free(psd, psd_pool); + pkt_bio_finished(pd); +} + +static void pkt_make_request_read(struct pktcdvd_device *pd, struct bio *bio) +{ + struct bio *cloned_bio = bio_clone(bio, GFP_NOIO); + struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO); + + psd->pd = pd; + psd->bio = bio; + cloned_bio->bi_bdev = pd->bdev; + cloned_bio->bi_private = psd; + cloned_bio->bi_end_io = pkt_end_io_read_cloned; + pd->stats.secs_r += bio_sectors(bio); + pkt_queue_bio(pd, cloned_bio); +} + +static void pkt_make_request_write(struct request_queue *q, struct bio *bio) +{ + struct pktcdvd_device *pd = q->queuedata; + sector_t zone; + struct packet_data *pkt; + int was_empty, blocked_bio; + struct pkt_rb_node *node; + + zone = get_zone(bio->bi_iter.bi_sector, pd); + + /* + * If we find a matching packet in state WAITING or READ_WAIT, we can + * just append this bio to that packet. + */ + spin_lock(&pd->cdrw.active_list_lock); + blocked_bio = 0; + list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) { + if (pkt->sector == zone) { + spin_lock(&pkt->lock); + if ((pkt->state == PACKET_WAITING_STATE) || + (pkt->state == PACKET_READ_WAIT_STATE)) { + bio_list_add(&pkt->orig_bios, bio); + pkt->write_size += + bio->bi_iter.bi_size / CD_FRAMESIZE; + if ((pkt->write_size >= pkt->frames) && + (pkt->state == PACKET_WAITING_STATE)) { + atomic_inc(&pkt->run_sm); + wake_up(&pd->wqueue); + } + spin_unlock(&pkt->lock); + spin_unlock(&pd->cdrw.active_list_lock); + return; + } else { + blocked_bio = 1; + } + spin_unlock(&pkt->lock); + } + } + spin_unlock(&pd->cdrw.active_list_lock); + + /* + * Test if there is enough room left in the bio work queue + * (queue size >= congestion on mark). + * If not, wait till the work queue size is below the congestion off mark. + */ + spin_lock(&pd->lock); + if (pd->write_congestion_on > 0 + && pd->bio_queue_size >= pd->write_congestion_on) { + set_bdi_congested(&q->backing_dev_info, BLK_RW_ASYNC); + do { + spin_unlock(&pd->lock); + congestion_wait(BLK_RW_ASYNC, HZ); + spin_lock(&pd->lock); + } while(pd->bio_queue_size > pd->write_congestion_off); + } + spin_unlock(&pd->lock); + + /* + * No matching packet found. Store the bio in the work queue. + */ + node = mempool_alloc(pd->rb_pool, GFP_NOIO); + node->bio = bio; + spin_lock(&pd->lock); + BUG_ON(pd->bio_queue_size < 0); + was_empty = (pd->bio_queue_size == 0); + pkt_rbtree_insert(pd, node); + spin_unlock(&pd->lock); + + /* + * Wake up the worker thread. + */ + atomic_set(&pd->scan_queue, 1); + if (was_empty) { + /* This wake_up is required for correct operation */ + wake_up(&pd->wqueue); + } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) { + /* + * This wake up is not required for correct operation, + * but improves performance in some cases. + */ + wake_up(&pd->wqueue); + } +} + +static void pkt_make_request(struct request_queue *q, struct bio *bio) +{ + struct pktcdvd_device *pd; + char b[BDEVNAME_SIZE]; + struct bio *split; + + 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); + return; + } + + 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; + } + + blk_queue_bounce(q, &bio); + + 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, + GFP_NOIO, fs_bio_set); + bio_chain(split, bio); + } else { + split = bio; + } + + pkt_make_request_write(q, split); + } while (split != bio); + + return; +end_io: + bio_io_error(bio); +} + + + +static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd, + struct bio_vec *bvec) +{ + struct pktcdvd_device *pd = q->queuedata; + sector_t zone = get_zone(bmd->bi_sector, pd); + int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size; + int remaining = (pd->settings.size << 9) - used; + int remaining2; + + /* + * A bio <= PAGE_SIZE must be allowed. If it crosses a packet + * boundary, pkt_make_request() will split the bio. + */ + remaining2 = PAGE_SIZE - bmd->bi_size; + remaining = max(remaining, remaining2); + + BUG_ON(remaining < 0); + return remaining; +} + +static void pkt_init_queue(struct pktcdvd_device *pd) +{ + struct request_queue *q = pd->disk->queue; + + blk_queue_make_request(q, pkt_make_request); + blk_queue_logical_block_size(q, CD_FRAMESIZE); + blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS); + blk_queue_merge_bvec(q, pkt_merge_bvec); + q->queuedata = pd; +} + +static int pkt_seq_show(struct seq_file *m, void *p) +{ + struct pktcdvd_device *pd = m->private; + char *msg; + char bdev_buf[BDEVNAME_SIZE]; + int states[PACKET_NUM_STATES]; + + seq_printf(m, "Writer %s mapped to %s:\n", pd->name, + bdevname(pd->bdev, bdev_buf)); + + seq_printf(m, "\nSettings:\n"); + seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2); + + if (pd->settings.write_type == 0) + msg = "Packet"; + else + msg = "Unknown"; + seq_printf(m, "\twrite type:\t\t%s\n", msg); + + seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable"); + seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss); + + seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode); + + if (pd->settings.block_mode == PACKET_BLOCK_MODE1) + msg = "Mode 1"; + else if (pd->settings.block_mode == PACKET_BLOCK_MODE2) + msg = "Mode 2"; + else + msg = "Unknown"; + seq_printf(m, "\tblock mode:\t\t%s\n", msg); + + seq_printf(m, "\nStatistics:\n"); + seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started); + seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended); + seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1); + seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1); + seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1); + + seq_printf(m, "\nMisc:\n"); + seq_printf(m, "\treference count:\t%d\n", pd->refcnt); + seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags); + seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed); + seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed); + seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset); + seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset); + + seq_printf(m, "\nQueue state:\n"); + seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size); + seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios)); + seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector); + + pkt_count_states(pd, states); + seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n", + states[0], states[1], states[2], states[3], states[4], states[5]); + + seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n", + pd->write_congestion_off, + pd->write_congestion_on); + return 0; +} + +static int pkt_seq_open(struct inode *inode, struct file *file) +{ + return single_open(file, pkt_seq_show, PDE_DATA(inode)); +} + +static const struct file_operations pkt_proc_fops = { + .open = pkt_seq_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release +}; + +static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev) +{ + int i; + int ret = 0; + char b[BDEVNAME_SIZE]; + struct block_device *bdev; + + if (pd->pkt_dev == dev) { + pkt_err(pd, "recursive setup not allowed\n"); + return -EBUSY; + } + for (i = 0; i < MAX_WRITERS; i++) { + struct pktcdvd_device *pd2 = pkt_devs[i]; + if (!pd2) + continue; + if (pd2->bdev->bd_dev == dev) { + pkt_err(pd, "%s already setup\n", + bdevname(pd2->bdev, b)); + return -EBUSY; + } + if (pd2->pkt_dev == dev) { + pkt_err(pd, "can't chain pktcdvd devices\n"); + return -EBUSY; + } + } + + bdev = bdget(dev); + if (!bdev) + return -ENOMEM; + ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL); + if (ret) + return ret; + + /* This is safe, since we have a reference from open(). */ + __module_get(THIS_MODULE); + + pd->bdev = bdev; + set_blocksize(bdev, CD_FRAMESIZE); + + pkt_init_queue(pd); + + atomic_set(&pd->cdrw.pending_bios, 0); + pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name); + if (IS_ERR(pd->cdrw.thread)) { + pkt_err(pd, "can't start kernel thread\n"); + ret = -ENOMEM; + goto out_mem; + } + + proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd); + pkt_dbg(1, pd, "writer mapped to %s\n", bdevname(bdev, b)); + return 0; + +out_mem: + blkdev_put(bdev, FMODE_READ | FMODE_NDELAY); + /* This is safe: open() is still holding a reference. */ + module_put(THIS_MODULE); + return ret; +} + +static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg) +{ + struct pktcdvd_device *pd = bdev->bd_disk->private_data; + int ret; + + pkt_dbg(2, pd, "cmd %x, dev %d:%d\n", + cmd, MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev)); + + mutex_lock(&pktcdvd_mutex); + switch (cmd) { + case CDROMEJECT: + /* + * The door gets locked when the device is opened, so we + * have to unlock it or else the eject command fails. + */ + if (pd->refcnt == 1) + pkt_lock_door(pd, 0); + /* fallthru */ + /* + * forward selected CDROM ioctls to CD-ROM, for UDF + */ + case CDROMMULTISESSION: + case CDROMREADTOCENTRY: + case CDROM_LAST_WRITTEN: + case CDROM_SEND_PACKET: + case SCSI_IOCTL_SEND_COMMAND: + ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg); + break; + + default: + pkt_dbg(2, pd, "Unknown ioctl (%x)\n", cmd); + ret = -ENOTTY; + } + mutex_unlock(&pktcdvd_mutex); + + return ret; +} + +static unsigned int pkt_check_events(struct gendisk *disk, + unsigned int clearing) +{ + struct pktcdvd_device *pd = disk->private_data; + struct gendisk *attached_disk; + + if (!pd) + return 0; + if (!pd->bdev) + return 0; + attached_disk = pd->bdev->bd_disk; + if (!attached_disk || !attached_disk->fops->check_events) + return 0; + return attached_disk->fops->check_events(attached_disk, clearing); +} + +static const struct block_device_operations pktcdvd_ops = { + .owner = THIS_MODULE, + .open = pkt_open, + .release = pkt_close, + .ioctl = pkt_ioctl, + .check_events = pkt_check_events, +}; + +static char *pktcdvd_devnode(struct gendisk *gd, umode_t *mode) +{ + return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name); +} + +/* + * Set up mapping from pktcdvd device to CD-ROM device. + */ +static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev) +{ + int idx; + int ret = -ENOMEM; + struct pktcdvd_device *pd; + struct gendisk *disk; + + mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); + + for (idx = 0; idx < MAX_WRITERS; idx++) + if (!pkt_devs[idx]) + break; + if (idx == MAX_WRITERS) { + pr_err("max %d writers supported\n", MAX_WRITERS); + ret = -EBUSY; + goto out_mutex; + } + + pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL); + if (!pd) + goto out_mutex; + + pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE, + sizeof(struct pkt_rb_node)); + if (!pd->rb_pool) + goto out_mem; + + INIT_LIST_HEAD(&pd->cdrw.pkt_free_list); + INIT_LIST_HEAD(&pd->cdrw.pkt_active_list); + spin_lock_init(&pd->cdrw.active_list_lock); + + spin_lock_init(&pd->lock); + spin_lock_init(&pd->iosched.lock); + bio_list_init(&pd->iosched.read_queue); + bio_list_init(&pd->iosched.write_queue); + sprintf(pd->name, DRIVER_NAME"%d", idx); + init_waitqueue_head(&pd->wqueue); + pd->bio_queue = RB_ROOT; + + pd->write_congestion_on = write_congestion_on; + pd->write_congestion_off = write_congestion_off; + + disk = alloc_disk(1); + if (!disk) + goto out_mem; + pd->disk = disk; + disk->major = pktdev_major; + disk->first_minor = idx; + disk->fops = &pktcdvd_ops; + disk->flags = GENHD_FL_REMOVABLE; + strcpy(disk->disk_name, pd->name); + disk->devnode = pktcdvd_devnode; + disk->private_data = pd; + disk->queue = blk_alloc_queue(GFP_KERNEL); + if (!disk->queue) + goto out_mem2; + + pd->pkt_dev = MKDEV(pktdev_major, idx); + ret = pkt_new_dev(pd, dev); + if (ret) + goto out_new_dev; + + /* inherit events of the host device */ + disk->events = pd->bdev->bd_disk->events; + disk->async_events = pd->bdev->bd_disk->async_events; + + add_disk(disk); + + pkt_sysfs_dev_new(pd); + pkt_debugfs_dev_new(pd); + + pkt_devs[idx] = pd; + if (pkt_dev) + *pkt_dev = pd->pkt_dev; + + mutex_unlock(&ctl_mutex); + return 0; + +out_new_dev: + blk_cleanup_queue(disk->queue); +out_mem2: + put_disk(disk); +out_mem: + if (pd->rb_pool) + mempool_destroy(pd->rb_pool); + kfree(pd); +out_mutex: + mutex_unlock(&ctl_mutex); + pr_err("setup of pktcdvd device failed\n"); + return ret; +} + +/* + * Tear down mapping from pktcdvd device to CD-ROM device. + */ +static int pkt_remove_dev(dev_t pkt_dev) +{ + struct pktcdvd_device *pd; + int idx; + int ret = 0; + + mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); + + for (idx = 0; idx < MAX_WRITERS; idx++) { + pd = pkt_devs[idx]; + if (pd && (pd->pkt_dev == pkt_dev)) + break; + } + if (idx == MAX_WRITERS) { + pr_debug("dev not setup\n"); + ret = -ENXIO; + goto out; + } + + if (pd->refcnt > 0) { + ret = -EBUSY; + goto out; + } + if (!IS_ERR(pd->cdrw.thread)) + kthread_stop(pd->cdrw.thread); + + pkt_devs[idx] = NULL; + + pkt_debugfs_dev_remove(pd); + pkt_sysfs_dev_remove(pd); + + blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY); + + remove_proc_entry(pd->name, pkt_proc); + pkt_dbg(1, pd, "writer unmapped\n"); + + del_gendisk(pd->disk); + blk_cleanup_queue(pd->disk->queue); + put_disk(pd->disk); + + mempool_destroy(pd->rb_pool); + kfree(pd); + + /* This is safe: open() is still holding a reference. */ + module_put(THIS_MODULE); + +out: + mutex_unlock(&ctl_mutex); + return ret; +} + +static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd) +{ + struct pktcdvd_device *pd; + + mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); + + pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index); + if (pd) { + ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev); + ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev); + } else { + ctrl_cmd->dev = 0; + ctrl_cmd->pkt_dev = 0; + } + ctrl_cmd->num_devices = MAX_WRITERS; + + mutex_unlock(&ctl_mutex); +} + +static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + void __user *argp = (void __user *)arg; + struct pkt_ctrl_command ctrl_cmd; + int ret = 0; + dev_t pkt_dev = 0; + + if (cmd != PACKET_CTRL_CMD) + return -ENOTTY; + + if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command))) + return -EFAULT; + + switch (ctrl_cmd.command) { + case PKT_CTRL_CMD_SETUP: + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev); + ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev); + break; + case PKT_CTRL_CMD_TEARDOWN: + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev)); + break; + case PKT_CTRL_CMD_STATUS: + pkt_get_status(&ctrl_cmd); + break; + default: + return -ENOTTY; + } + + if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command))) + return -EFAULT; + return ret; +} + +#ifdef CONFIG_COMPAT +static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg)); +} +#endif + +static const struct file_operations pkt_ctl_fops = { + .open = nonseekable_open, + .unlocked_ioctl = pkt_ctl_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = pkt_ctl_compat_ioctl, +#endif + .owner = THIS_MODULE, + .llseek = no_llseek, +}; + +static struct miscdevice pkt_misc = { + .minor = MISC_DYNAMIC_MINOR, + .name = DRIVER_NAME, + .nodename = "pktcdvd/control", + .fops = &pkt_ctl_fops +}; + +static int __init pkt_init(void) +{ + int ret; + + mutex_init(&ctl_mutex); + + psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE, + sizeof(struct packet_stacked_data)); + if (!psd_pool) + return -ENOMEM; + + ret = register_blkdev(pktdev_major, DRIVER_NAME); + if (ret < 0) { + pr_err("unable to register block device\n"); + goto out2; + } + if (!pktdev_major) + pktdev_major = ret; + + ret = pkt_sysfs_init(); + if (ret) + goto out; + + pkt_debugfs_init(); + + ret = misc_register(&pkt_misc); + if (ret) { + pr_err("unable to register misc device\n"); + goto out_misc; + } + + pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL); + + return 0; + +out_misc: + pkt_debugfs_cleanup(); + pkt_sysfs_cleanup(); +out: + unregister_blkdev(pktdev_major, DRIVER_NAME); +out2: + mempool_destroy(psd_pool); + return ret; +} + +static void __exit pkt_exit(void) +{ + remove_proc_entry("driver/"DRIVER_NAME, NULL); + misc_deregister(&pkt_misc); + + pkt_debugfs_cleanup(); + pkt_sysfs_cleanup(); + + unregister_blkdev(pktdev_major, DRIVER_NAME); + mempool_destroy(psd_pool); +} + +MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives"); +MODULE_AUTHOR("Jens Axboe <axboe@suse.de>"); +MODULE_LICENSE("GPL"); + +module_init(pkt_init); +module_exit(pkt_exit); |