[PATCH 2/6] cdrom: remove the unused cdrom_media_changed function

Christoph Hellwig
2020-07-08T12:35:09Z

As well as the ->media_changed method. All these are left over from
before the drivers were switched over to the check_events scheme.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
Documentation/cdrom/cdrom-standard.rst | 18 +----------------
drivers/cdrom/cdrom.c | 28 +++++---------------------
include/linux/cdrom.h | 2 --
3 files changed, 6 insertions(+), 42 deletions(-)

diff --git a/Documentation/cdrom/cdrom-standard.rst b/Documentation/cdrom/cdrom-standard.rst
index dde4f7f7fdbf1c..2de90581059033 100644
--- a/Documentation/cdrom/cdrom-standard.rst
+++ b/Documentation/cdrom/cdrom-standard.rst
@@ -157,7 +157,6 @@ with the kernel as a block device by registering the following general
cdrom_release, /∗ release ∗/
NULL, /∗ fsync ∗/
NULL, /∗ fasync ∗/
- cdrom_media_changed, /∗ media change ∗/
NULL /∗ revalidate ∗/
};

@@ -366,19 +365,6 @@ which may or may not be in the drive). If the drive is not a changer,
CDS_DRIVE_NOT_READY /* something is wrong, tray is moving? */
CDS_DISC_OK /* a disc is loaded and everything is fine */

-::
-
- int media_changed(struct cdrom_device_info *cdi, int disc_nr)
-
-This function is very similar to the original function in $struct
-file_operations*. It returns 1 if the medium of the device *cdi->dev*
-has changed since the last call, and 0 otherwise. The parameter
-*disc_nr* identifies a specific slot in a juke-box, it should be
-ignored for single-disc drives. Note that by `re-routing` this
-function through *cdrom_media_changed()*, we can implement separate
-queues for the VFS and a new *ioctl()* function that can report device
-changes to software (e. g., an auto-mounting daemon).
-
::

int tray_move(struct cdrom_device_info *cdi, int position)
@@ -917,9 +903,7 @@ commands can be identified by the underscores in their names.
maximum number of discs in the juke-box found in the *cdrom_dops*.
`CDROM_MEDIA_CHANGED`
Returns 1 if a disc has been changed since the last call.
- Note that calls to *cdrom_media_changed* by the VFS are treated
- by an independent queue, so both mechanisms will detect a
- media change once. For juke-boxes, an extra argument *arg*
+ For juke-boxes, an extra argument *arg*
specifies the slot for which the information is given. The special
value *CDSL_CURRENT* requests that information about the currently
selected slot be returned.
diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
index d82b3b7658bddc..0c271b9e3c5b79 100644
--- a/drivers/cdrom/cdrom.c
+++ b/drivers/cdrom/cdrom.c
@@ -605,7 +605,7 @@ int register_cdrom(struct gendisk *disk, struct cdrom_device_info *cdi)
disk->cdi = cdi;

ENSURE(cdo, drive_status, CDC_DRIVE_STATUS);
- if (cdo->check_events == NULL && cdo->media_changed == NULL)
+ if (cdo->check_events == NULL)
WARN_ON_ONCE(cdo->capability & (CDC_MEDIA_CHANGED | CDC_SELECT_DISC));
ENSURE(cdo, tray_move, CDC_CLOSE_TRAY | CDC_OPEN_TRAY);
ENSURE(cdo, lock_door, CDC_LOCK);
@@ -1419,8 +1419,6 @@ static int cdrom_select_disc(struct cdrom_device_info *cdi, int 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 */
@@ -1517,13 +1515,10 @@ int media_changed(struct cdrom_device_info *cdi, int queue)
return ret;

/* changed since last call? */
- 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);
+ 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;

if (changed) {
cdi->mc_flags = 0x3; /* set bit on both queues */
@@ -1535,18 +1530,6 @@ int media_changed(struct cdrom_device_info *cdi, int queue)
return ret;
}

-int cdrom_media_changed(struct cdrom_device_info *cdi)
-{
- /* This talks to the VFS, which doesn't like errors - just 1 or 0.
- * Returning "0" is always safe (media hasn't been changed). Do that
- * if the low-level cdrom driver dosn't support media changed. */
- if (cdi == NULL || cdi->ops->media_changed == NULL)
- return 0;
- if (!CDROM_CAN(CDC_MEDIA_CHANGED))
- return 0;
- return media_changed(cdi, 0);
-}
-
/* Requests to the low-level drivers will /always/ be done in the
following format convention:

@@ -3464,7 +3447,6 @@ EXPORT_SYMBOL(unregister_cdrom);
EXPORT_SYMBOL(cdrom_open);
EXPORT_SYMBOL(cdrom_release);
EXPORT_SYMBOL(cdrom_ioctl);
-EXPORT_SYMBOL(cdrom_media_changed);
EXPORT_SYMBOL(cdrom_number_of_slots);
EXPORT_SYMBOL(cdrom_mode_select);
EXPORT_SYMBOL(cdrom_mode_sense);
diff --git a/include/linux/cdrom.h b/include/linux/cdrom.h
index 8543fa59da7207..f48d0a31deaece 100644
--- a/include/linux/cdrom.h
+++ b/include/linux/cdrom.h
@@ -73,7 +73,6 @@ struct cdrom_device_ops {
int (*drive_status) (struct cdrom_device_info *, int);
unsigned int (*check_events) (struct cdrom_device_info *cdi,
unsigned int clearing, int slot);
- int (*media_changed) (struct cdrom_device_info *, int);
int (*tray_move) (struct cdrom_device_info *, int);
int (*lock_door) (struct cdrom_device_info *, int);
int (*select_speed) (struct cdrom_device_info *, int);
@@ -107,7 +106,6 @@ extern int cdrom_ioctl(struct cdrom_device_info *cdi, struct block_device *bdev,
fmode_t mode, unsigned int cmd, unsigned long arg);
extern unsigned int cdrom_check_events(struct cdrom_device_info *cdi,
unsigned int clearing);
-extern int cdrom_media_changed(struct cdrom_device_info *);

extern int register_cdrom(struct gendisk *disk, struct cdrom_device_info *cdi);
extern void unregister_cdrom(struct cdrom_device_info *cdi);
--
2.26.2