diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2018-09-07 16:49:43 +0200 |
|---|---|---|
| committer | Arnd Bergmann <arnd@arndb.de> | 2019-10-23 17:23:44 +0200 |
| commit | 1207045da5a7c94344e0ea9a9e7495985eef499a (patch) | |
| tree | a7f6028469b50532252bbdd7b71b0f06e293a90e /drivers/ide | |
| parent | 01b8bca81e181ccca475e1fdb92ebb00d9d9b547 (diff) | |
compat_ioctl: move tape handling into drivers
MTIOCPOS and MTIOCGET are incompatible between 32-bit and 64-bit user
space, and traditionally have been translated in fs/compat_ioctl.c.
To get rid of that translation handler, move a corresponding
implementation into each of the four drivers implementing those commands.
The interesting part of that is now in a new linux/mtio.h header that
wraps the existing uapi/linux/mtio.h header and provides an abstraction
to let drivers handle both cases easily. Using an in_compat_syscall()
check, the caller does not have to keep track of whether this was
called through .unlocked_ioctl() or .compat_ioctl().
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Kai Mäkisara" <Kai.Makisara@kolumbus.fi>
Cc: linux-scsi@vger.kernel.org
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'drivers/ide')
| -rw-r--r-- | drivers/ide/ide-tape.c | 27 |
1 files changed, 21 insertions, 6 deletions
diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c index db1a65f4b490..3e7482695f77 100644 --- a/drivers/ide/ide-tape.c +++ b/drivers/ide/ide-tape.c @@ -19,6 +19,7 @@ #define IDETAPE_VERSION "1.20" +#include <linux/compat.h> #include <linux/module.h> #include <linux/types.h> #include <linux/string.h> @@ -1407,14 +1408,10 @@ static long do_idetape_chrdev_ioctl(struct file *file, if (tape->drv_write_prot) mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); - if (copy_to_user(argp, &mtget, sizeof(struct mtget))) - return -EFAULT; - return 0; + return put_user_mtget(argp, &mtget); case MTIOCPOS: mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; - if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) - return -EFAULT; - return 0; + return put_user_mtpos(argp, &mtpos); default: if (tape->chrdev_dir == IDETAPE_DIR_READ) ide_tape_discard_merge_buffer(drive, 1); @@ -1432,6 +1429,22 @@ static long idetape_chrdev_ioctl(struct file *file, return ret; } +static long idetape_chrdev_compat_ioctl(struct file *file, + unsigned int cmd, unsigned long arg) +{ + long ret; + + if (cmd == MTIOCPOS32) + cmd = MTIOCPOS; + else if (cmd == MTIOCGET32) + cmd = MTIOCGET; + + mutex_lock(&ide_tape_mutex); + ret = do_idetape_chrdev_ioctl(file, cmd, arg); + mutex_unlock(&ide_tape_mutex); + return ret; +} + /* * Do a mode sense page 0 with block descriptor and if it succeeds set the tape * block size with the reported value. @@ -1886,6 +1899,8 @@ static const struct file_operations idetape_fops = { .read = idetape_chrdev_read, .write = idetape_chrdev_write, .unlocked_ioctl = idetape_chrdev_ioctl, + .compat_ioctl = IS_ENABLED(CONFIG_COMPAT) ? + idetape_chrdev_compat_ioctl : NULL, .open = idetape_chrdev_open, .release = idetape_chrdev_release, .llseek = noop_llseek, |