diff options
Diffstat (limited to 'drivers/cdrom/cdrom.c')
| -rw-r--r-- | drivers/cdrom/cdrom.c | 69 |
1 files changed, 60 insertions, 9 deletions
diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c index af13c62dc47..75fb965b8f7 100644 --- a/drivers/cdrom/cdrom.c +++ b/drivers/cdrom/cdrom.c @@ -30,7 +30,7 @@ changelog for the 1.x series, David? 2.00 Dec 2, 1997 -- Erik Andersen <andersee@debian.org> - -- New maintainer! As David A. van Leeuwen has been too busy to activly + -- New maintainer! As David A. van Leeuwen has been too busy to actively maintain and improve this driver, I am now carrying on the torch. If you have a problem with this driver, please feel free to contact me. @@ -409,7 +409,8 @@ int register_cdrom(struct cdrom_device_info *cdi) } ENSURE(drive_status, CDC_DRIVE_STATUS ); - ENSURE(media_changed, CDC_MEDIA_CHANGED); + if (cdo->check_events == NULL && cdo->media_changed == NULL) + *change_capability = ~(CDC_MEDIA_CHANGED | CDC_SELECT_DISC); ENSURE(tray_move, CDC_CLOSE_TRAY | CDC_OPEN_TRAY); ENSURE(lock_door, CDC_LOCK); ENSURE(select_speed, CDC_SELECT_SPEED); @@ -985,6 +986,9 @@ int cdrom_open(struct cdrom_device_info *cdi, struct block_device *bdev, fmode_t cdinfo(CD_OPEN, "entering cdrom_open\n"); + /* open is event synchronization point, check events first */ + check_disk_change(bdev); + /* if this was a O_NONBLOCK open and we should honor the flags, * do a quick open without drive/disc integrity checks. */ cdi->use_count++; @@ -1011,9 +1015,6 @@ int cdrom_open(struct cdrom_device_info *cdi, struct block_device *bdev, fmode_t cdinfo(CD_OPEN, "Use count for \"/dev/%s\" now %d\n", cdi->name, cdi->use_count); - /* Do this on open. Don't wait for mount, because they might - not be mounting, but opening with O_NONBLOCK */ - check_disk_change(bdev); return 0; err_release: if (CDROM_CAN(CDC_LOCK) && cdi->options & CDO_LOCK) { @@ -1348,7 +1349,10 @@ static int cdrom_select_disc(struct cdrom_device_info *cdi, int slot) if (!CDROM_CAN(CDC_SELECT_DISC)) return -EDRIVE_CANT_DO_THIS; - (void) cdi->ops->media_changed(cdi, slot); + if (cdi->ops->check_events) + cdi->ops->check_events(cdi, 0, slot); + else + cdi->ops->media_changed(cdi, slot); if (slot == CDSL_NONE) { /* set media changed bits, on both queues */ @@ -1392,6 +1396,42 @@ static int cdrom_select_disc(struct cdrom_device_info *cdi, int slot) return slot; } +/* + * As cdrom implements an extra ioctl consumer for media changed + * event, it needs to buffer ->check_events() output, such that event + * is not lost for both the usual VFS and ioctl paths. + * cdi->{vfs|ioctl}_events are used to buffer pending events for each + * path. + * + * XXX: Locking is non-existent. cdi->ops->check_events() can be + * called in parallel and buffering fields are accessed without any + * exclusion. The original media_changed code had the same problem. + * It might be better to simply deprecate CDROM_MEDIA_CHANGED ioctl + * and remove this cruft altogether. It doesn't have much usefulness + * at this point. + */ +static void cdrom_update_events(struct cdrom_device_info *cdi, + unsigned int clearing) +{ + unsigned int events; + + events = cdi->ops->check_events(cdi, clearing, CDSL_CURRENT); + cdi->vfs_events |= events; + cdi->ioctl_events |= events; +} + +unsigned int cdrom_check_events(struct cdrom_device_info *cdi, + unsigned int clearing) +{ + unsigned int events; + + cdrom_update_events(cdi, clearing); + events = cdi->vfs_events; + cdi->vfs_events = 0; + return events; +} +EXPORT_SYMBOL(cdrom_check_events); + /* We want to make media_changed accessible to the user through an * ioctl. The main problem now is that we must double-buffer the * low-level implementation, to assure that the VFS and the user both @@ -1403,15 +1443,26 @@ int media_changed(struct cdrom_device_info *cdi, int queue) { unsigned int mask = (1 << (queue & 1)); int ret = !!(cdi->mc_flags & mask); + bool changed; if (!CDROM_CAN(CDC_MEDIA_CHANGED)) - return ret; + return ret; + /* changed since last call? */ - if (cdi->ops->media_changed(cdi, CDSL_CURRENT)) { + if (cdi->ops->check_events) { + BUG_ON(!queue); /* shouldn't be called from VFS path */ + cdrom_update_events(cdi, DISK_EVENT_MEDIA_CHANGE); + changed = cdi->ioctl_events & DISK_EVENT_MEDIA_CHANGE; + cdi->ioctl_events = 0; + } else + changed = cdi->ops->media_changed(cdi, CDSL_CURRENT); + + if (changed) { cdi->mc_flags = 0x3; /* set bit on both queues */ ret |= 1; cdi->media_written = 0; } + cdi->mc_flags &= ~mask; /* clear bit */ return ret; } @@ -2469,7 +2520,7 @@ static int cdrom_ioctl_drive_status(struct cdrom_device_info *cdi, /* * Ok, this is where problems start. The current interface for the * CDROM_DISC_STATUS ioctl is flawed. It makes the false assumption that - * CDs are all CDS_DATA_1 or all CDS_AUDIO, etc. Unfortunatly, while this + * CDs are all CDS_DATA_1 or all CDS_AUDIO, etc. Unfortunately, while this * is often the case, it is also very common for CDs to have some tracks * with data, and some tracks with audio. Just because I feel like it, * I declare the following to be the best way to cope. If the CD has ANY |