[6/7] isofs: stop using ioctl_by_bdev

Instead just call the CD-ROM layer functionality directly, and turn the
hot mess in isofs_get_last_session into remotely readable code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/isofs/inode.c | 54 +++++++++++++++++++++++-------------------------
 1 file changed, 26 insertions(+), 28 deletions(-)

On 2020/04/23 16:16, Christoph Hellwig wrote:
> Instead just call the CD-ROM layer functionality directly, and turn the
> hot mess in isofs_get_last_session into remotely readable code.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  fs/isofs/inode.c | 54 +++++++++++++++++++++++-------------------------
>  1 file changed, 26 insertions(+), 28 deletions(-)
> 
> diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
> index 62c0462dc89f..fc48923a9b6c 100644
> --- a/fs/isofs/inode.c
> +++ b/fs/isofs/inode.c
> @@ -544,43 +544,41 @@ static int isofs_show_options(struct seq_file *m, struct dentry *root)
>  
>  static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
>  {
> -	struct cdrom_multisession ms_info;
> -	unsigned int vol_desc_start;
> -	struct block_device *bdev = sb->s_bdev;
> -	int i;
> +	struct cdrom_device_info *cdi = disk_to_cdi(sb->s_bdev->bd_disk);
> +	unsigned int vol_desc_start = 0;
>  
> -	vol_desc_start=0;
> -	ms_info.addr_format=CDROM_LBA;
>  	if (session > 0) {
> -		struct cdrom_tocentry Te;
> -		Te.cdte_track=session;
> -		Te.cdte_format=CDROM_LBA;
> -		i = ioctl_by_bdev(bdev, CDROMREADTOCENTRY, (unsigned long) &Te);
> -		if (!i) {
> +		struct cdrom_tocentry te;
> +
> +		if (!cdi)
> +			return -EINVAL;
> +
> +		te.cdte_track = session;
> +		te.cdte_format = CDROM_LBA;
> +		if (cdrom_read_tocentry(cdi, &te) == 0) {
>  			printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
> -				session, Te.cdte_addr.lba,
> -				Te.cdte_ctrl&CDROM_DATA_TRACK);
> -			if ((Te.cdte_ctrl&CDROM_DATA_TRACK) == 4)
> -				return Te.cdte_addr.lba;
> +				session, te.cdte_addr.lba,
> +				te.cdte_ctrl & CDROM_DATA_TRACK);
> +			if ((te.cdte_ctrl & CDROM_DATA_TRACK) == 4)
> +				return te.cdte_addr.lba;
>  		}
>  
>  		printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
>  	}
> -	i = ioctl_by_bdev(bdev, CDROMMULTISESSION, (unsigned long) &ms_info);
> -	if (session > 0)
> -		printk(KERN_ERR "ISOFS: Invalid session number\n");
> -#if 0
> -	printk(KERN_DEBUG "isofs.inode: CDROMMULTISESSION: rc=%d\n",i);
> -	if (i==0) {
> -		printk(KERN_DEBUG "isofs.inode: XA disk: %s\n",ms_info.xa_flag?"yes":"no");
> -		printk(KERN_DEBUG "isofs.inode: vol_desc_start = %d\n", ms_info.addr.lba);
> -	}
> -#endif
> -	if (i==0)
> +
> +	if (cdi) {
> +		struct cdrom_multisession ms_info;
> +
> +		ms_info.addr_format = CDROM_LBA;
> +		if (cdrom_multisession(cdi, &ms_info) == 0) {
>  #if WE_OBEY_THE_WRITTEN_STANDARDS
> -		if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
> +			/* necessary for a valid ms_info.addr */
> +			if (ms_info.xa_flag)
>  #endif
> -			vol_desc_start=ms_info.addr.lba;
> +				vol_desc_start = ms_info.addr.lba;
> +		}
> +	}
> +
>  	return vol_desc_start;
>  }
>  
> 

Looks OK to me.

Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>

On Thu 23-04-20 09:12:23, Christoph Hellwig wrote:
> Instead just call the CD-ROM layer functionality directly, and turn the
> hot mess in isofs_get_last_session into remotely readable code.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

One comment below...

> ---
>  fs/isofs/inode.c | 54 +++++++++++++++++++++++-------------------------
>  1 file changed, 26 insertions(+), 28 deletions(-)
> 
> diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
> index 62c0462dc89f..fc48923a9b6c 100644
> --- a/fs/isofs/inode.c
> +++ b/fs/isofs/inode.c
> @@ -544,43 +544,41 @@ static int isofs_show_options(struct seq_file *m, struct dentry *root)
>  
>  static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
>  {
> -	struct cdrom_multisession ms_info;
> -	unsigned int vol_desc_start;
> -	struct block_device *bdev = sb->s_bdev;
> -	int i;
> +	struct cdrom_device_info *cdi = disk_to_cdi(sb->s_bdev->bd_disk);
> +	unsigned int vol_desc_start = 0;
>  
> -	vol_desc_start=0;
> -	ms_info.addr_format=CDROM_LBA;
>  	if (session > 0) {
> -		struct cdrom_tocentry Te;
> -		Te.cdte_track=session;
> -		Te.cdte_format=CDROM_LBA;
> -		i = ioctl_by_bdev(bdev, CDROMREADTOCENTRY, (unsigned long) &Te);
> -		if (!i) {
> +		struct cdrom_tocentry te;
> +
> +		if (!cdi)
> +			return -EINVAL;

There's no error handling in the caller and this function actually returns
unsigned int... So I believe you need to return 0 here to maintain previous
behavior (however suspicious it may be)?

								Honza

On Thu, Apr 23, 2020 at 01:03:47PM +0200, Jan Kara wrote:
> There's no error handling in the caller and this function actually returns
> unsigned int... So I believe you need to return 0 here to maintain previous
> behavior (however suspicious it may be)?

Indeed, and I don't think it is suspicious at all - if we have no CDROM
info we should assume session 0, which is the same as for non-CDROM
devices.  Fixed for the next version.

On Fri 24-04-20 08:52:53, Christoph Hellwig wrote:
> On Thu, Apr 23, 2020 at 01:03:47PM +0200, Jan Kara wrote:
> > There's no error handling in the caller and this function actually returns
> > unsigned int... So I believe you need to return 0 here to maintain previous
> > behavior (however suspicious it may be)?
> 
> Indeed, and I don't think it is suspicious at all - if we have no CDROM
> info we should assume session 0, which is the same as for non-CDROM
> devices.  Fixed for the next version.

Right, I've realized that once I've checked UDF version and thought about
it for a while...

								Honza