[PATCH 3/8] cdrom: factor out a cdrom_read_tocentry helper

From: Christoph Hellwig
Date: Mon May 04 2020 - 10:00:10 EST


Factor out a version of the CDROMREADTOCENTRY ioctl handler that can
be called directly from kernel space.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Damien Le Moal <damien.lemoal@xxxxxxx>
Reviewed-by: Hannes Reinecke <hare@xxxxxxx
---
drivers/cdrom/cdrom.c | 39 ++++++++++++++++++++++-----------------
include/linux/cdrom.h | 3 +++
2 files changed, 25 insertions(+), 17 deletions(-)

diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
index a1d2112fd283f..c91d1e1382142 100644
--- a/drivers/cdrom/cdrom.c
+++ b/drivers/cdrom/cdrom.c
@@ -2666,32 +2666,37 @@ static int cdrom_ioctl_read_tochdr(struct cdrom_device_info *cdi,
return 0;
}

+int cdrom_read_tocentry(struct cdrom_device_info *cdi,
+ struct cdrom_tocentry *entry)
+{
+ u8 requested_format = entry->cdte_format;
+ int ret;
+
+ if (requested_format != CDROM_MSF && requested_format != CDROM_LBA)
+ return -EINVAL;
+
+ /* make interface to low-level uniform */
+ entry->cdte_format = CDROM_MSF;
+ ret = cdi->ops->audio_ioctl(cdi, CDROMREADTOCENTRY, entry);
+ if (!ret)
+ sanitize_format(&entry->cdte_addr, &entry->cdte_format,
+ requested_format);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(cdrom_read_tocentry);
+
static int cdrom_ioctl_read_tocentry(struct cdrom_device_info *cdi,
void __user *argp)
{
struct cdrom_tocentry entry;
- u8 requested_format;
int ret;

- /* cd_dbg(CD_DO_IOCTL, "entering CDROMREADTOCENTRY\n"); */
-
if (copy_from_user(&entry, argp, sizeof(entry)))
return -EFAULT;
-
- requested_format = entry.cdte_format;
- if (requested_format != CDROM_MSF && requested_format != CDROM_LBA)
- return -EINVAL;
- /* make interface to low-level uniform */
- entry.cdte_format = CDROM_MSF;
- ret = cdi->ops->audio_ioctl(cdi, CDROMREADTOCENTRY, &entry);
- if (ret)
- return ret;
- sanitize_format(&entry.cdte_addr, &entry.cdte_format, requested_format);
-
- if (copy_to_user(argp, &entry, sizeof(entry)))
+ ret = cdrom_read_tocentry(cdi, &entry);
+ if (!ret && copy_to_user(argp, &entry, sizeof(entry)))
return -EFAULT;
- /* cd_dbg(CD_DO_IOCTL, "CDROMREADTOCENTRY successful\n"); */
- return 0;
+ return ret;
}

static int cdrom_ioctl_play_msf(struct cdrom_device_info *cdi,
diff --git a/include/linux/cdrom.h b/include/linux/cdrom.h
index 4f74ce050253d..008c4d79fa332 100644
--- a/include/linux/cdrom.h
+++ b/include/linux/cdrom.h
@@ -94,6 +94,9 @@ struct cdrom_device_ops {
struct packet_command *);
};

+int cdrom_read_tocentry(struct cdrom_device_info *cdi,
+ struct cdrom_tocentry *entry);
+
/* the general block_device operations structure: */
extern int cdrom_open(struct cdrom_device_info *cdi, struct block_device *bdev,
fmode_t mode);
--
2.26.2