/* * Copyright (C) 2000 Jens Axboe * Copyright (C) 2001-2004 Peter Osterlund * Copyright (C) 2006 Thomas Maier * * 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, * such as drivers/scsi/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 ->submit_bio 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DRIVER_NAME "pktcdvd" #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 bio_set pkt_bio_set; /* /sys/class/pktcdvd */ static struct class 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 sector_t get_zone(sector_t sector, struct pktcdvd_device *pd) { return (sector + pd->offset) & ~(sector_t)(pd->settings.size - 1); } /********************************************************** * sysfs interface for pktcdvd * by (C) 2006 Thomas Maier /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 **********************************************************/ static ssize_t packets_started_show(struct device *dev, struct device_attribute *attr, char *buf) { struct pktcdvd_device *pd = dev_get_drvdata(dev); return sysfs_emit(buf, "%lu\n", pd->stats.pkt_started); } static DEVICE_ATTR_RO(packets_started); static ssize_t packets_finished_show(struct device *dev, struct device_attribute *attr, char *buf) { struct pktcdvd_device *pd = dev_get_drvdata(dev); return sysfs_emit(buf, "%lu\n", pd->stats.pkt_ended); } static DEVICE_ATTR_RO(packets_finished); static ssize_t kb_written_show(struct device *dev, struct device_attribute *attr, char *buf) { struct pktcdvd_device *pd = dev_get_drvdata(dev); return sysfs_emit(buf, "%lu\n", pd->stats.secs_w >> 1); } static DEVICE_ATTR_RO(kb_written); static ssize_t kb_read_show(struct device *dev, struct device_attribute *attr, char *buf) { struct pktcdvd_device *pd = dev_get_drvdata(dev); return sysfs_emit(buf, "%lu\n", pd->stats.secs_r >> 1); } static DEVICE_ATTR_RO(kb_read); static ssize_t kb_read_gather_show(struct device *dev, struct device_attribute *attr, char *buf) { struct pktcdvd_device *pd = dev_get_drvdata(dev); return sysfs_emit(buf, "%lu\n", pd->stats.secs_rg >> 1); } static DEVICE_ATTR_RO(kb_read_gather); static ssize_t reset_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { struct pktcdvd_device *pd = dev_get_drvdata(dev); if (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; } return len; } static DEVICE_ATTR_WO(reset); static struct attribute *pkt_stat_attrs[] = { &dev_attr_packets_finished.attr, &dev_attr_packets_started.attr, &dev_attr_kb_read.attr, &dev_attr_kb_written.attr, &dev_attr_kb_read_gather.attr, &dev_attr_reset.attr, NULL, }; static const struct attribute_group pkt_stat_group = { .name = "stat", .attrs = pkt_stat_attrs, }; static ssize_t size_show(struct device *dev, struct device_attribute *attr, char *buf) { struct pktcdvd_device *pd = dev_get_drvdata(dev); int n; spin_lock(&pd->lock); n = sysfs_emit(buf, "%d\n", pd->bio_queue_size); spin_unlock(&pd->lock); return n; } static DEVICE_ATTR_RO(size); 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 congestion_off_show(struct device *dev, struct device_attribute *attr, char *buf) { struct pktcdvd_device *pd = dev_get_drvdata(dev); int n; spin_lock(&pd->lock); n = sysfs_emit(buf, "%d\n", pd->write_congestion_off); spin_unlock(&pd->lock); return n; } static ssize_t congestion_off_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { struct pktcdvd_device *pd = dev_get_drvdata(dev); int val, ret; ret = kstrtoint(buf, 10, &val); if (ret) return ret; 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); return len; } static DEVICE_ATTR_RW(congestion_off); static ssize_t congestion_on_show(struct device *dev, struct device_attribute *attr, char *buf) { struct pktcdvd_device *pd = dev_get_drvdata(dev); int n; spin_lock(&pd->lock); n = sysfs_emit(buf, "%d\n", pd->write_congestion_on); spin_unlock(&pd->lock); return n; } static ssize_t congestion_on_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { struct pktcdvd_device *pd = dev_get_drvdata(dev); int val, ret; ret = kstrtoint(buf, 10, &val); if (ret) return ret; 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 DEVICE_ATTR_RW(congestion_on); static struct attribute *pkt_wq_attrs[] = { &dev_attr_congestion_on.attr, &dev_attr_congestion_off.attr, &dev_attr_size.attr, NULL, }; static const struct attribute_group pkt_wq_group = { .name = "write_queue", .attrs = pkt_wq_attrs, }; static const struct attribute_group *pkt_groups[] = { &pkt_stat_group, &pkt_wq_group, NULL, }; static void pkt_sysfs_dev_new(struct pktcdvd_device *pd) { if (class_is_registered(&class_pktcdvd)) { pd->dev = device_create_with_groups(&class_pktcdvd, NULL, MKDEV(0, 0), pd, pkt_groups, "%s", pd->disk->disk_name); if (IS_ERR(pd->dev)) pd->dev = NULL; } } static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd) { if (class_is_registered(&class_pktcdvd)) device_unregister(pd->dev); } /******************************************************************** /sys/class/pktcdvd/ add map block device remove unmap packet dev device_map show mappings *******************************************************************/ static ssize_t device_map_show(const struct class *c, const 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 += sysfs_emit_at(data, n, "%s %u:%u %u:%u\n", pd->disk->disk_name, MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev), MAJOR(file_bdev(pd->bdev_file)->bd_dev), MINOR(file_bdev(pd->bdev_file)->bd_dev)); } mutex_unlock(&ctl_mutex); return n; } static CLASS_ATTR_RO(device_map); static ssize_t add_store(const struct class *c, const 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 CLASS_ATTR_WO(add); static ssize_t remove_store(const struct class *c, const 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 CLASS_ATTR_WO(remove); static struct attribute *class_pktcdvd_attrs[] = { &class_attr_add.attr, &class_attr_remove.attr, &class_attr_device_map.attr, NULL, }; ATTRIBUTE_GROUPS(class_pktcdvd); static struct class class_pktcdvd = { .name = DRIVER_NAME, .class_groups = class_pktcdvd_groups, }; static int pkt_sysfs_init(void) { /* * create control files in sysfs * /sys/class/pktcdvd/... */ return class_register(&class_pktcdvd); } static void pkt_sysfs_cleanup(void) { class_unregister(&class_pktcdvd); } /******************************************************************** entries in debugfs /sys/kernel/debug/pktcdvd[0-7]/ info *******************************************************************/ 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); } static int pkt_seq_show(struct seq_file *m, void *p) { struct pktcdvd_device *pd = m->private; char *msg; int states[PACKET_NUM_STATES]; seq_printf(m, "Writer %s mapped to %pg:\n", pd->disk->disk_name, file_bdev(pd->bdev_file)); 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", 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; } DEFINE_SHOW_ATTRIBUTE(pkt_seq); static void pkt_debugfs_dev_new(struct pktcdvd_device *pd) { if (!pkt_debugfs_root) return; pd->dfs_d_root = debugfs_create_dir(pd->disk->disk_name, pkt_debugfs_root); pd->dfs_f_info = debugfs_create_file("info", 0444, pd->dfs_d_root, pd, &pkt_seq_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) { struct device *ddev = disk_to_dev(pd->disk); BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0); if (atomic_dec_and_test(&pd->cdrw.pending_bios)) { dev_dbg(ddev, "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(frames, GFP_KERNEL); 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++) { pkt->r_bios[i] = bio_kmalloc(1, GFP_KERNEL); if (!pkt->r_bios[i]) goto no_rd_bio; } return pkt; no_rd_bio: for (i = 0; i < frames; i++) kfree(pkt->r_bios[i]); no_page: for (i = 0; i < frames / FRAMES_PER_PAGE; i++) if (pkt->pages[i]) __free_page(pkt->pages[i]); kfree(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++) kfree(pkt->r_bios[i]); for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++) __free_page(pkt->pages[i]); kfree(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(file_bdev(pd->bdev_file)); struct scsi_cmnd *scmd; struct request *rq; int ret = 0; rq = scsi_alloc_request(q, (cgc->data_direction == CGC_DATA_WRITE) ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0); if (IS_ERR(rq)) return PTR_ERR(rq); scmd = blk_mq_rq_to_pdu(rq); if (cgc->buflen) { ret = blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, GFP_NOIO); if (ret) goto out; } scmd->cmd_len = COMMAND_SIZE(cgc->cmd[0]); memcpy(scmd->cmnd, cgc->cmd, CDROM_PACKET_SIZE); rq->timeout = 60*HZ; if (cgc->quiet) rq->rq_flags |= RQF_QUIET; blk_execute_rq(rq, false); if (scmd->result) ret = -EIO; out: blk_mq_free_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 device *ddev = disk_to_dev(pd->disk); struct scsi_sense_hdr *sshdr = cgc->sshdr; if (sshdr) dev_err(ddev, "%*ph - sense %02x.%02x.%02x (%s)\n", CDROM_PACKET_SIZE, cgc->cmd, sshdr->sense_key, sshdr->asc, sshdr->ascq, sense_key_string(sshdr->sense_key)); else dev_err(ddev, "%*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 scsi_sense_hdr sshdr; int ret; init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE); cgc.sshdr = &sshdr; cgc.cmd[0] = GPCMD_SET_SPEED; put_unaligned_be16(read_speed, &cgc.cmd[2]); put_unaligned_be16(write_speed, &cgc.cmd[4]); ret = pkt_generic_packet(pd, &cgc); if (ret) 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) { /* * Some CDRW drives can not handle writes larger than one packet, * even if the size is a multiple of the packet size. */ bio->bi_opf |= REQ_NOMERGE; 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) { struct device *ddev = disk_to_dev(pd->disk); 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) { dev_dbg(ddev, "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) { dev_dbg(ddev, "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); submit_bio_noacct(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) { struct device *ddev = disk_to_dev(pd->disk); 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; } 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; } dev_err(ddev, "cdrom max_phys_segments too small\n"); return -EIO; } static void pkt_end_io_read(struct bio *bio) { struct packet_data *pkt = bio->bi_private; struct pktcdvd_device *pd = pkt->pd; BUG_ON(!pd); dev_dbg(disk_to_dev(pd->disk), "bio=%p sec0=%llx sec=%llx err=%d\n", bio, pkt->sector, bio->bi_iter.bi_sector, bio->bi_status); if (bio->bi_status) atomic_inc(&pkt->io_errors); bio_uninit(bio); 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) { struct packet_data *pkt = bio->bi_private; struct pktcdvd_device *pd = pkt->pd; BUG_ON(!pd); dev_dbg(disk_to_dev(pd->disk), "id=%d, err=%d\n", pkt->id, bio->bi_status); pd->stats.pkt_ended++; bio_uninit(bio); 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) { struct device *ddev = disk_to_dev(pd->disk); 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) { dev_dbg(ddev, "zone %llx cached\n", 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_init(bio, file_bdev(pd->bdev_file), bio->bi_inline_vecs, 1, REQ_OP_READ); bio->bi_iter.bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9); bio->bi_end_io = pkt_end_io_read; bio->bi_private = pkt; p = (f * CD_FRAMESIZE) / PAGE_SIZE; offset = (f * CD_FRAMESIZE) % PAGE_SIZE; dev_dbg(ddev, "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); pkt_queue_bio(pd, bio); frames_read++; } out_account: dev_dbg(ddev, "need %d frames for zone %llx\n", frames_read, 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); } } static inline void pkt_set_state(struct device *ddev, struct packet_data *pkt, enum packet_data_state state) { static const char *state_name[] = { "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED" }; enum packet_data_state old_state = pkt->state; dev_dbg(ddev, "pkt %2d : s=%6llx %s -> %s\n", pkt->id, pkt->sector, state_name[old_state], state_name[state]); 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 device *ddev = disk_to_dev(pd->disk); 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; atomic_set(&pd->scan_queue, 0); if (list_empty(&pd->cdrw.pkt_free_list)) { dev_dbg(ddev, "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) { dev_dbg(ddev, "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); dev_dbg(ddev, "looking for zone %llx\n", zone); while ((node = pkt_rbtree_find(pd, zone)) != NULL) { sector_t tmp = get_zone(node->bio->bi_iter.bi_sector, pd); bio = node->bio; dev_dbg(ddev, "found zone=%llx\n", tmp); if (tmp != 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 */ if (pd->congested && pd->bio_queue_size <= pd->write_congestion_off) { pd->congested = false; wake_up_var(&pd->congested); } spin_unlock(&pd->lock); pkt->sleep_time = max(PACKET_WAIT_TIME, 1); pkt_set_state(ddev, 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; } /** * bio_list_copy_data - copy contents of data buffers from one chain of bios to * another * @src: source bio list * @dst: destination bio list * * Stops when it reaches the end of either the @src list or @dst list - that is, * copies min(src->bi_size, dst->bi_size) bytes (or the equivalent for lists of * bios). */ static void bio_list_copy_data(struct bio *dst, struct bio *src) { struct bvec_iter src_iter = src->bi_iter; struct bvec_iter dst_iter = dst->bi_iter; while (1) { if (!src_iter.bi_size) { src = src->bi_next; if (!src) break; src_iter = src->bi_iter; } if (!dst_iter.bi_size) { dst = dst->bi_next; if (!dst) break; dst_iter = dst->bi_iter; } bio_copy_data_iter(dst, &dst_iter, src, &src_iter); } } /* * 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) { struct device *ddev = disk_to_dev(pd->disk); int f; bio_init(pkt->w_bio, file_bdev(pd->bdev_file), pkt->w_bio->bi_inline_vecs, pkt->frames, REQ_OP_WRITE); pkt->w_bio->bi_iter.bi_sector = pkt->sector; 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++) { 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)) BUG(); } dev_dbg(ddev, "vcnt=%d\n", pkt->w_bio->bi_vcnt); /* * Fill-in bvec with data from orig_bios. */ spin_lock(&pkt->lock); bio_list_copy_data(pkt->w_bio, pkt->orig_bios.head); pkt_set_state(ddev, pkt, PACKET_WRITE_WAIT_STATE); spin_unlock(&pkt->lock); dev_dbg(ddev, "Writing %d frames for zone %llx\n", pkt->write_size, pkt->sector); if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) pkt->cache_valid = 1; else pkt->cache_valid = 0; /* Start the write request */ atomic_set(&pkt->io_wait, 1); pkt_queue_bio(pd, pkt->w_bio); } static void pkt_finish_packet(struct packet_data *pkt, blk_status_t status) { struct bio *bio; if (status) pkt->cache_valid = 0; /* Finish all bios corresponding to this packet */ while ((bio = bio_list_pop(&pkt->orig_bios))) { bio->bi_status = status; bio_endio(bio); } } static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt) { struct device *ddev = disk_to_dev(pd->disk); dev_dbg(ddev, "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(ddev, 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(ddev, 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 (!pkt->w_bio->bi_status) { pkt_set_state(ddev, pkt, PACKET_FINISHED_STATE); } else { pkt_set_state(ddev, pkt, PACKET_RECOVERY_STATE); } break; case PACKET_RECOVERY_STATE: dev_dbg(ddev, "No recovery possible\n"); pkt_set_state(ddev, pkt, PACKET_FINISHED_STATE); break; case PACKET_FINISHED_STATE: pkt_finish_packet(pkt, pkt->w_bio->bi_status); return; default: BUG(); break; } } } static void pkt_handle_packets(struct pktcdvd_device *pd) { struct device *ddev = disk_to_dev(pd->disk); 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(ddev, pkt, PACKET_IDLE_STATE); atomic_set(&pd->scan_queue, 1); } } 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 device *ddev = disk_to_dev(pd->disk); struct packet_data *pkt; int states[PACKET_NUM_STATES]; 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 */ pkt_count_states(pd, states); dev_dbg(ddev, "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; } dev_dbg(ddev, "sleeping\n"); residue = schedule_timeout(min_sleep_time); dev_dbg(ddev, "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) { dev_info(disk_to_dev(pd->disk), "%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); put_unaligned_be16(cgc->buflen, &cgc->cmd[7]); 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 */ put_unaligned_be16(cgc->buflen, &cgc->cmd[7]); 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; ret = pkt_generic_packet(pd, &cgc); if (ret) 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; put_unaligned_be16(track, &cgc.cmd[4]); cgc.cmd[8] = 8; cgc.quiet = 1; ret = pkt_generic_packet(pd, &cgc); if (ret) 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; ret = pkt_get_disc_info(pd, &di); if (ret) return ret; last_track = (di.last_track_msb << 8) | di.last_track_lsb; ret = pkt_get_track_info(pd, last_track, 1, &ti); if (ret) return ret; /* if this track is blank, try the previous. */ if (ti.blank) { last_track--; ret = pkt_get_track_info(pd, last_track, 1, &ti); if (ret) 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 device *ddev = disk_to_dev(pd->disk); struct packet_command cgc; struct scsi_sense_hdr sshdr; 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.sshdr = &sshdr; ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0); if (ret) { pkt_dump_sense(pd, &cgc); return ret; } size = 2 + get_unaligned_be16(&buffer[0]); pd->mode_offset = get_unaligned_be16(&buffer[6]); if (size > sizeof(buffer)) size = sizeof(buffer); /* * now get it all */ init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ); cgc.sshdr = &sshdr; ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0); if (ret) { 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 */ dev_err(ddev, "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; ret = pkt_mode_select(pd, &cgc); if (ret) { 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) { struct device *ddev = disk_to_dev(pd->disk); 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; dev_err(ddev, "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) { struct device *ddev = disk_to_dev(pd->disk); 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: dev_dbg(ddev, "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) { dev_notice(ddev, "unknown disc - no track?\n"); return 0; } if (di->disc_type != 0x20 && di->disc_type != 0) { dev_err(ddev, "wrong disc type (%x)\n", di->disc_type); return 0; } if (di->erasable == 0) { dev_err(ddev, "disc not erasable\n"); return 0; } if (di->border_status == PACKET_SESSION_RESERVED) { dev_err(ddev, "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 device *ddev = disk_to_dev(pd->disk); 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 : get_unaligned_be16(&buf[6]); memset(&di, 0, sizeof(disc_information)); memset(&ti, 0, sizeof(track_information)); ret = pkt_get_disc_info(pd, &di); if (ret) { dev_err(ddev, "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; */ ret = pkt_get_track_info(pd, track, 1, &ti); if (ret) { dev_err(ddev, "failed get_track\n"); return ret; } if (!pkt_writable_track(pd, &ti)) { dev_err(ddev, "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) { dev_notice(ddev, "detected zero packet size!\n"); return -ENXIO; } if (pd->settings.size > PACKET_MAX_SECTORS) { dev_err(ddev, "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: dev_err(ddev, "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) { struct device *ddev = disk_to_dev(pd->disk); struct packet_command cgc; struct scsi_sense_hdr sshdr; unsigned char buf[64]; bool set = IS_ENABLED(CONFIG_CDROM_PKTCDVD_WCACHE); int ret; init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ); cgc.sshdr = &sshdr; cgc.buflen = pd->mode_offset + 12; /* * caching mode page might not be there, so quiet this command */ cgc.quiet = 1; ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0); if (ret) return ret; /* * use drive write caching -- we need deferred error handling to be * able to successfully recover with this option (drive will return good * status as soon as the cdb is validated). */ buf[pd->mode_offset + 10] |= (set << 2); cgc.buflen = cgc.cmd[8] = 2 + get_unaligned_be16(&buf[0]); ret = pkt_mode_select(pd, &cgc); if (ret) { dev_err(ddev, "write caching control failed\n"); pkt_dump_sense(pd, &cgc); } else if (!ret && set) dev_notice(ddev, "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 scsi_sense_hdr sshdr; 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.sshdr = &sshdr; 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 = get_unaligned_be16(&cap_buf[30]); if (num_spdb > 0) offset = 34; } *write_speed = get_unaligned_be16(&cap_buf[offset]); 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 device *ddev = disk_to_dev(pd->disk); struct packet_command cgc; struct scsi_sense_hdr sshdr; unsigned char buf[64]; unsigned int size, st, sp; int ret; init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ); cgc.sshdr = &sshdr; 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 = 2 + get_unaligned_be16(&buf[0]); if (size > sizeof(buf)) size = sizeof(buf); init_cdrom_command(&cgc, buf, size, CGC_DATA_READ); cgc.sshdr = &sshdr; 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)) { dev_notice(ddev, "disc type is not CD-RW\n"); return 1; } if (!(buf[6] & 0x4)) { dev_notice(ddev, "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: dev_notice(ddev, "unknown disc sub-type %d\n", st); return 1; } if (*speed) { dev_info(ddev, "maximum media speed: %d\n", *speed); return 0; } else { dev_notice(ddev, "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 device *ddev = disk_to_dev(pd->disk); struct packet_command cgc; struct scsi_sense_hdr sshdr; int ret; dev_dbg(ddev, "Performing OPC\n"); init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE); cgc.sshdr = &sshdr; cgc.timeout = 60*HZ; cgc.cmd[0] = GPCMD_SEND_OPC; cgc.cmd[1] = 1; ret = pkt_generic_packet(pd, &cgc); if (ret) pkt_dump_sense(pd, &cgc); return ret; } static int pkt_open_write(struct pktcdvd_device *pd) { struct device *ddev = disk_to_dev(pd->disk); int ret; unsigned int write_speed, media_write_speed, read_speed; ret = pkt_probe_settings(pd); if (ret) { dev_dbg(ddev, "failed probe\n"); return ret; } ret = pkt_set_write_settings(pd); if (ret) { dev_notice(ddev, "failed saving write settings\n"); return -EIO; } pkt_write_caching(pd); ret = pkt_get_max_speed(pd, &write_speed); if (ret) write_speed = 16 * 177; switch (pd->mmc3_profile) { case 0x13: /* DVD-RW */ case 0x1a: /* DVD+RW */ case 0x12: /* DVD-RAM */ dev_notice(ddev, "write speed %ukB/s\n", write_speed); break; default: ret = pkt_media_speed(pd, &media_write_speed); if (ret) media_write_speed = 16; write_speed = min(write_speed, media_write_speed * 177); dev_notice(ddev, "write speed %ux\n", write_speed / 176); break; } read_speed = write_speed; ret = pkt_set_speed(pd, write_speed, read_speed); if (ret) { dev_notice(ddev, "couldn't set write speed\n"); return -EIO; } pd->write_speed = write_speed; pd->read_speed = read_speed; ret = pkt_perform_opc(pd); if (ret) dev_notice(ddev, "Optimum Power Calibration failed\n"); return 0; } /* * called at open time. */ static int pkt_open_dev(struct pktcdvd_device *pd, bool write) { struct device *ddev = disk_to_dev(pd->disk); int ret; long lba; struct request_queue *q; struct file *bdev_file; /* * 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 open should not fail. */ bdev_file = bdev_file_open_by_dev(file_bdev(pd->bdev_file)->bd_dev, BLK_OPEN_READ, pd, NULL); if (IS_ERR(bdev_file)) { ret = PTR_ERR(bdev_file); goto out; } pd->f_open_bdev = bdev_file; ret = pkt_get_last_written(pd, &lba); if (ret) { dev_err(ddev, "pkt_get_last_written failed\n"); goto out_putdev; } set_capacity(pd->disk, lba << 2); set_capacity_and_notify(file_bdev(pd->bdev_file)->bd_disk, lba << 2); q = bdev_get_queue(file_bdev(pd->bdev_file)); if (write) { ret = pkt_open_write(pd); if (ret) goto out_putdev; set_bit(PACKET_WRITABLE, &pd->flags); } else { pkt_set_speed(pd, MAX_SPEED, MAX_SPEED); clear_bit(PACKET_WRITABLE, &pd->flags); } ret = pkt_set_segment_merging(pd, q); if (ret) goto out_putdev; if (write) { if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) { dev_err(ddev, "not enough memory for buffers\n"); ret = -ENOMEM; goto out_putdev; } dev_info(ddev, "%lukB available on disc\n", lba << 1); } set_blocksize(bdev_file, CD_FRAMESIZE); return 0; out_putdev: fput(bdev_file); 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) { struct device *ddev = disk_to_dev(pd->disk); if (flush && pkt_flush_cache(pd)) dev_notice(ddev, "not flushing cache\n"); pkt_lock_door(pd, 0); pkt_set_speed(pd, MAX_SPEED, MAX_SPEED); fput(pd->f_open_bdev); pd->f_open_bdev = NULL; pkt_shrink_pktlist(pd); } static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor) { if (dev_minor >= MAX_WRITERS) return NULL; dev_minor = array_index_nospec(dev_minor, MAX_WRITERS); return pkt_devs[dev_minor]; } static int pkt_open(struct gendisk *disk, blk_mode_t mode) { struct pktcdvd_device *pd = NULL; int ret; mutex_lock(&pktcdvd_mutex); mutex_lock(&ctl_mutex); pd = pkt_find_dev_from_minor(disk->first_minor); if (!pd) { ret = -ENODEV; goto out; } BUG_ON(pd->refcnt < 0); pd->refcnt++; if (pd->refcnt > 1) { if ((mode & BLK_OPEN_WRITE) && !test_bit(PACKET_WRITABLE, &pd->flags)) { ret = -EBUSY; goto out_dec; } } else { ret = pkt_open_dev(pd, mode & BLK_OPEN_WRITE); if (ret) goto out_dec; } 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_release(struct gendisk *disk) { 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) { struct packet_stacked_data *psd = bio->bi_private; struct pktcdvd_device *pd = psd->pd; psd->bio->bi_status = bio->bi_status; bio_put(bio); bio_endio(psd->bio); 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_alloc_clone(file_bdev(pd->bdev_file), bio, GFP_NOIO, &pkt_bio_set); struct packet_stacked_data *psd = mempool_alloc(&psd_pool, GFP_NOIO); psd->pd = pd; psd->bio = bio; 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 bio *bio) { struct pktcdvd_device *pd = bio->bi_bdev->bd_disk->private_data; 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) { struct wait_bit_queue_entry wqe; init_wait_var_entry(&wqe, &pd->congested, 0); for (;;) { prepare_to_wait_event(__var_waitqueue(&pd->congested), &wqe.wq_entry, TASK_UNINTERRUPTIBLE); if (pd->bio_queue_size <= pd->write_congestion_off) break; pd->congested = true; spin_unlock(&pd->lock); schedule(); spin_lock(&pd->lock); } } 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_submit_bio(struct bio *bio) { struct pktcdvd_device *pd = bio->bi_bdev->bd_disk->private_data; struct device *ddev = disk_to_dev(pd->disk); struct bio *split; bio = bio_split_to_limits(bio); if (!bio) return; dev_dbg(ddev, "start = %6llx stop = %6llx\n", bio->bi_iter.bi_sector, 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)) { dev_notice(ddev, "WRITE for ro device (%llu)\n", bio->bi_iter.bi_sector); goto end_io; } if (!bio->bi_iter.bi_size || (bio->bi_iter.bi_size % CD_FRAMESIZE)) { dev_err(ddev, "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, GFP_NOIO, &pkt_bio_set); bio_chain(split, bio); } else { split = bio; } pkt_make_request_write(split); } while (split != bio); return; end_io: bio_io_error(bio); } static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev) { struct device *ddev = disk_to_dev(pd->disk); int i; struct file *bdev_file; struct scsi_device *sdev; if (pd->pkt_dev == dev) { dev_err(ddev, "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 (file_bdev(pd2->bdev_file)->bd_dev == dev) { dev_err(ddev, "%pg already setup\n", file_bdev(pd2->bdev_file)); return -EBUSY; } if (pd2->pkt_dev == dev) { dev_err(ddev, "can't chain pktcdvd devices\n"); return -EBUSY; } } bdev_file = bdev_file_open_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_NDELAY, NULL, NULL); if (IS_ERR(bdev_file)) return PTR_ERR(bdev_file); sdev = scsi_device_from_queue(file_bdev(bdev_file)->bd_disk->queue); if (!sdev) { fput(bdev_file); return -EINVAL; } put_device(&sdev->sdev_gendev); /* This is safe, since we have a reference from open(). */ __module_get(THIS_MODULE); pd->bdev_file = bdev_file; atomic_set(&pd->cdrw.pending_bios, 0); pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->disk->disk_name); if (IS_ERR(pd->cdrw.thread)) { dev_err(ddev, "can't start kernel thread\n"); goto out_mem; } proc_create_single_data(pd->disk->disk_name, 0, pkt_proc, pkt_seq_show, pd); dev_notice(ddev, "writer mapped to %pg\n", file_bdev(bdev_file)); return 0; out_mem: fput(bdev_file); /* This is safe: open() is still holding a reference. */ module_put(THIS_MODULE); return -ENOMEM; } static int pkt_ioctl(struct block_device *bdev, blk_mode_t mode, unsigned int cmd, unsigned long arg) { struct pktcdvd_device *pd = bdev->bd_disk->private_data; struct device *ddev = disk_to_dev(pd->disk); int ret; dev_dbg(ddev, "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); fallthrough; /* * 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: if (!bdev->bd_disk->fops->ioctl) ret = -ENOTTY; else ret = bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg); break; default: dev_dbg(ddev, "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_file) return 0; attached_disk = file_bdev(pd->bdev_file)->bd_disk; if (!attached_disk || !attached_disk->fops->check_events) return 0; return attached_disk->fops->check_events(attached_disk, clearing); } static char *pkt_devnode(struct gendisk *disk, umode_t *mode) { return kasprintf(GFP_KERNEL, "pktcdvd/%s", disk->disk_name); } static const struct block_device_operations pktcdvd_ops = { .owner = THIS_MODULE, .submit_bio = pkt_submit_bio, .open = pkt_open, .release = pkt_release, .ioctl = pkt_ioctl, .compat_ioctl = blkdev_compat_ptr_ioctl, .check_events = pkt_check_events, .devnode = pkt_devnode, }; /* * Set up mapping from pktcdvd device to CD-ROM device. */ static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev) { struct queue_limits lim = { .max_hw_sectors = PACKET_MAX_SECTORS, .logical_block_size = CD_FRAMESIZE, .features = BLK_FEAT_ROTATIONAL, }; 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; ret = mempool_init_kmalloc_pool(&pd->rb_pool, PKT_RB_POOL_SIZE, sizeof(struct pkt_rb_node)); if (ret) 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); 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 = blk_alloc_disk(&lim, NUMA_NO_NODE); if (IS_ERR(disk)) { ret = PTR_ERR(disk); goto out_mem; } pd->disk = disk; disk->major = pktdev_major; disk->first_minor = idx; disk->minors = 1; disk->fops = &pktcdvd_ops; disk->flags = GENHD_FL_REMOVABLE | GENHD_FL_NO_PART; snprintf(disk->disk_name, sizeof(disk->disk_name), DRIVER_NAME"%d", idx); disk->private_data = pd; pd->pkt_dev = MKDEV(pktdev_major, idx); ret = pkt_new_dev(pd, dev); if (ret) goto out_mem2; /* inherit events of the host device */ disk->events = file_bdev(pd->bdev_file)->bd_disk->events; ret = add_disk(disk); if (ret) goto out_mem2; 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_mem2: put_disk(disk); out_mem: mempool_exit(&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; struct device *ddev; 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; } ddev = disk_to_dev(pd->disk); 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); fput(pd->bdev_file); remove_proc_entry(pd->disk->disk_name, pkt_proc); dev_notice(ddev, "writer unmapped\n"); del_gendisk(pd->disk); put_disk(pd->disk); mempool_exit(&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(file_bdev(pd->bdev_file)->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, }; 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); ret = mempool_init_kmalloc_pool(&psd_pool, PSD_POOL_SIZE, sizeof(struct packet_stacked_data)); if (ret) return ret; ret = bioset_init(&pkt_bio_set, BIO_POOL_SIZE, 0, 0); if (ret) { mempool_exit(&psd_pool); return ret; } 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_exit(&psd_pool); bioset_exit(&pkt_bio_set); 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_exit(&psd_pool); bioset_exit(&pkt_bio_set); } MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives"); MODULE_AUTHOR("Jens Axboe "); MODULE_LICENSE("GPL"); module_init(pkt_init); module_exit(pkt_exit);