[GIT PULL v3 00/27] block, scsi: final compat_ioctl cleanup

[GIT PULL v3 00/27] block, scsi: final compat_ioctl cleanup

[Arnd Bergmann]

Hi Martin, James,

If this version seems ok to everyone, please pull into
the scsi tree.

The following changes since commit e42617b825f8073569da76dc4510bfa019b1c35a:

  Linux 5.5-rc4 (2019-12-08 14:57:55 -0800)

are available in the Git repository at:

  git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground.git tags/block-ioctl-cleanup-5.6

for you to fetch changes up to d1329555e914109846283e469b5077e7500ecfaf

  Documentation: document ioctl interfaces better (2019-12-17 22:45:18 +0100)

----------------------------------------------------------------
block, scsi: final compat_ioctl cleanup

This series concludes the work I did for linux-5.5 on the compat_ioctl()
cleanup, killing off fs/compat_ioctl.c and block/compat_ioctl.c by moving
everything into drivers.

Overall this would be a reduction both in complexity and line count, but
as I'm also adding documentation the overall number of lines increases
in the end.

My plan was originally to keep the SCSI and block parts separate.
This did not work easily because of interdependencies: I cannot
do the final SCSI cleanup in a good way without first addressing the
CDROM ioctls, so this is one series that I hope could be merged through
either the block or the scsi git trees, or possibly both if you can
pull in the same branch.

The series comes in these steps:

1. clean up the sg v3 interface as suggested by Linus. I have
   talked about this with Doug Gilbert as well, and he would
   rebase his sg v4 patches on top of "compat: scsi: sg: fix v3
   compat read/write interface"

2. Actually moving handlers out of block/compat_ioctl.c and
   block/scsi_ioctl.c into drivers, mixed in with cleanup
   patches

3. Document how to do this right. I keep getting asked about this,
   and it helps to point to some documentation file.

The branch is based on another one that fixes a couple of bugs found
during the creation of this series.

Changes since v2:
- Rebase to v5.5-rc4, which contains the earlier bugfixes
- Fix sr_block_compat_ioctl() error handling bug found by
  Ben Hutchings
- Fix idecd_locked_compat_ioctl() compat_ptr() bug
- Don't try to handle HDIO_DRIVE_TASKFILE in drivers/ide
- More documentation improvements

Changes since v1:
- move out the bugfixes into a branch for itself
- clean up scsi sg driver further as suggested by Christoph Hellwig
- avoid some ifdefs by moving compat_ptr() out of asm/compat.h
- split out the blkdev_compat_ptr_ioctl function; bug spotted by
  Ben Hutchings
- Improve formatting of documentation

[1] https://lore.kernel.org/linux-block/20191211204306.1207817-1-arnd@arndb.de/T/#m9f89df30565fc66abbded5d01f4db553b16f129f

----------------------------------------------------------------

Arnd Bergmann (22):
  compat: ARM64: always include asm-generic/compat.h
  compat: provide compat_ptr() on all architectures
  compat: scsi: sg: fix v3 compat read/write interface
  compat_ioctl: block: add blkdev_compat_ptr_ioctl
  compat_ioctl: ubd, aoe: use blkdev_compat_ptr_ioctl
  compat_ioctl: move CDROM_SEND_PACKET handling into scsi
  compat_ioctl: move CDROMREADADIO to cdrom.c
  compat_ioctl: cdrom: handle CDROM_LAST_WRITTEN
  compat_ioctl: block: handle cdrom compat ioctl in non-cdrom drivers
  compat_ioctl: add scsi_compat_ioctl
  compat_ioctl: bsg: add handler
  compat_ioctl: ide: floppy: add handler
  compat_ioctl: scsi: move ioctl handling into drivers
  compat_ioctl: move sys_compat_ioctl() to ioctl.c
  compat_ioctl: simplify the implementation
  compat_ioctl: move cdrom commands into cdrom.c
  compat_ioctl: scsi: handle HDIO commands from drivers
  compat_ioctl: move HDIO ioctl handling into drivers/ide
  compat_ioctl: block: move blkdev_compat_ioctl() into ioctl.c
  compat_ioctl: block: simplify compat_blkpg_ioctl()
  compat_ioctl: simplify up block/ioctl.c
  Documentation: document ioctl interfaces better

 Documentation/core-api/index.rst       |   1 +
 Documentation/core-api/ioctl.rst       | 253 +++++++++++++++
 arch/arm64/include/asm/compat.h        |  22 +-
 arch/mips/include/asm/compat.h         |  18 --
 arch/parisc/include/asm/compat.h       |  17 -
 arch/powerpc/include/asm/compat.h      |  17 -
 arch/powerpc/oprofile/backtrace.c      |   2 +-
 arch/s390/include/asm/compat.h         |   6 +-
 arch/sparc/include/asm/compat.h        |  17 -
 arch/um/drivers/ubd_kern.c             |   1 +
 arch/x86/include/asm/compat.h          |  17 -
 block/Makefile                         |   1 -
 block/bsg.c                            |   1 +
 block/compat_ioctl.c                   | 427 -------------------------
 block/ioctl.c                          | 319 ++++++++++++++----
 block/scsi_ioctl.c                     | 214 ++++++++-----
 drivers/ata/libata-scsi.c              |   9 +
 drivers/block/aoe/aoeblk.c             |   1 +
 drivers/block/floppy.c                 |   3 +
 drivers/block/paride/pcd.c             |   3 +
 drivers/block/paride/pd.c              |   1 +
 drivers/block/paride/pf.c              |   1 +
 drivers/block/pktcdvd.c                |  26 +-
 drivers/block/sunvdc.c                 |   1 +
 drivers/block/virtio_blk.c             |   3 +
 drivers/block/xen-blkfront.c           |   1 +
 drivers/cdrom/cdrom.c                  |  35 +-
 drivers/cdrom/gdrom.c                  |   3 +
 drivers/ide/ide-cd.c                   |  38 +++
 drivers/ide/ide-disk.c                 |   1 +
 drivers/ide/ide-floppy.c               |   4 +
 drivers/ide/ide-floppy.h               |   2 +
 drivers/ide/ide-floppy_ioctl.c         |  35 ++
 drivers/ide/ide-gd.c                   |  17 +
 drivers/ide/ide-ioctls.c               |  47 ++-
 drivers/ide/ide-tape.c                 |  11 +
 drivers/scsi/aic94xx/aic94xx_init.c    |   3 +
 drivers/scsi/ch.c                      |   9 +-
 drivers/scsi/hisi_sas/hisi_sas_v1_hw.c |   3 +
 drivers/scsi/hisi_sas/hisi_sas_v2_hw.c |   3 +
 drivers/scsi/hisi_sas/hisi_sas_v3_hw.c |   3 +
 drivers/scsi/ipr.c                     |   3 +
 drivers/scsi/isci/init.c               |   3 +
 drivers/scsi/mvsas/mv_init.c           |   3 +
 drivers/scsi/pm8001/pm8001_init.c      |   3 +
 drivers/scsi/scsi_ioctl.c              |  54 +++-
 drivers/scsi/sd.c                      |  50 ++-
 drivers/scsi/sg.c                      | 170 +++++-----
 drivers/scsi/sr.c                      |  53 ++-
 drivers/scsi/st.c                      |  51 +--
 fs/Makefile                            |   2 +-
 fs/compat_ioctl.c                      | 261 ---------------
 fs/internal.h                          |   6 -
 fs/ioctl.c                             | 131 ++++++--
 include/linux/blkdev.h                 |   7 +
 include/linux/compat.h                 |  18 ++
 include/linux/falloc.h                 |   2 -
 include/linux/fs.h                     |   4 -
 include/linux/ide.h                    |   2 +
 include/linux/libata.h                 |   6 +
 include/scsi/scsi_ioctl.h              |   1 +
 include/scsi/sg.h                      |  30 ++
 62 files changed, 1269 insertions(+), 1187 deletions(-)
 create mode 100644 Documentation/core-api/ioctl.rst
 delete mode 100644 block/compat_ioctl.c
 delete mode 100644 fs/compat_ioctl.c

-- 
2.20.0

Cc: linux-scsi@vger.kernel.org
Cc: linux-block@vger.kernel.org
Cc: y2038@lists.linaro.org
Cc: linux-kernel@vger.kernel.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Cc: linux-doc@vger.kernel.org
Cc: corbet@lwn.net
Cc: viro@zeniv.linux.org.uk
Cc: linux-fsdevel@vger.kernel.org
Cc: Jens Axboe <axboe@kernel.dk>

[PATCH v3 13/22] compat_ioctl: scsi: move ioctl handling into drivers

[Arnd Bergmann]

Each driver calling scsi_ioctl() gets an equivalent compat_ioctl()
handler that implements the same commands by calling scsi_compat_ioctl().

The scsi_cmd_ioctl() and scsi_cmd_blk_ioctl() functions are compatible
at this point, so any driver that calls those can do so for both native
and compat mode, with the argument passed through compat_ptr().

With this, we can remove the entries from fs/compat_ioctl.c.  The new
code is larger, but should be easier to maintain and keep updated with
newly added commands.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/block/virtio_blk.c |   3 +
 drivers/scsi/ch.c          |   9 ++-
 drivers/scsi/sd.c          |  50 ++++++--------
 drivers/scsi/sg.c          |  44 ++++++++-----
 drivers/scsi/sr.c          |  57 ++++++++++++++--
 drivers/scsi/st.c          |  51 ++++++++------
 fs/compat_ioctl.c          | 132 +------------------------------------
 7 files changed, 142 insertions(+), 204 deletions(-)

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 7ffd719d89de..fbbf18ac1d5d 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -405,6 +405,9 @@ static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
 
 static const struct block_device_operations virtblk_fops = {
 	.ioctl  = virtblk_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = blkdev_compat_ptr_ioctl,
+#endif
 	.owner  = THIS_MODULE,
 	.getgeo = virtblk_getgeo,
 };
diff --git a/drivers/scsi/ch.c b/drivers/scsi/ch.c
index 76751d6c7f0d..ed5f4a6ae270 100644
--- a/drivers/scsi/ch.c
+++ b/drivers/scsi/ch.c
@@ -872,6 +872,10 @@ static long ch_ioctl_compat(struct file * file,
 			    unsigned int cmd, unsigned long arg)
 {
 	scsi_changer *ch = file->private_data;
+	int retval = scsi_ioctl_block_when_processing_errors(ch->device, cmd,
+							file->f_flags & O_NDELAY);
+	if (retval)
+		return retval;
 
 	switch (cmd) {
 	case CHIOGPARAMS:
@@ -883,7 +887,7 @@ static long ch_ioctl_compat(struct file * file,
 	case CHIOINITELEM:
 	case CHIOSVOLTAG:
 		/* compatible */
-		return ch_ioctl(file, cmd, arg);
+		return ch_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
 	case CHIOGSTATUS32:
 	{
 		struct changer_element_status32 ces32;
@@ -898,8 +902,7 @@ static long ch_ioctl_compat(struct file * file,
 		return ch_gstatus(ch, ces32.ces_type, data);
 	}
 	default:
-		// return scsi_ioctl_compat(ch->device, cmd, (void*)arg);
-		return -ENOIOCTLCMD;
+		return scsi_compat_ioctl(ch->device, cmd, compat_ptr(arg));
 
 	}
 }
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index cea625906440..5afb0046b12a 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1465,13 +1465,12 @@ static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
  *	Note: most ioctls are forward onto the block subsystem or further
  *	down in the scsi subsystem.
  **/
-static int sd_ioctl(struct block_device *bdev, fmode_t mode,
-		    unsigned int cmd, unsigned long arg)
+static int sd_ioctl_common(struct block_device *bdev, fmode_t mode,
+			   unsigned int cmd, void __user *p)
 {
 	struct gendisk *disk = bdev->bd_disk;
 	struct scsi_disk *sdkp = scsi_disk(disk);
 	struct scsi_device *sdp = sdkp->device;
-	void __user *p = (void __user *)arg;
 	int error;
     
 	SCSI_LOG_IOCTL(1, sd_printk(KERN_INFO, sdkp, "sd_ioctl: disk=%s, "
@@ -1507,9 +1506,6 @@ static int sd_ioctl(struct block_device *bdev, fmode_t mode,
 			break;
 		default:
 			error = scsi_cmd_blk_ioctl(bdev, mode, cmd, p);
-			if (error != -ENOTTY)
-				break;
-			error = scsi_ioctl(sdp, cmd, p);
 			break;
 	}
 out:
@@ -1691,39 +1687,31 @@ static void sd_rescan(struct device *dev)
 	revalidate_disk(sdkp->disk);
 }
 
+static int sd_ioctl(struct block_device *bdev, fmode_t mode,
+		    unsigned int cmd, unsigned long arg)
+{
+	void __user *p = (void __user *)arg;
+	int ret;
+
+	ret = sd_ioctl_common(bdev, mode, cmd, p);
+	if (ret != -ENOTTY)
+		return ret;
+
+	return scsi_ioctl(scsi_disk(bdev->bd_disk)->device, cmd, p);
+}
 
 #ifdef CONFIG_COMPAT
-/* 
- * This gets directly called from VFS. When the ioctl 
- * is not recognized we go back to the other translation paths. 
- */
 static int sd_compat_ioctl(struct block_device *bdev, fmode_t mode,
 			   unsigned int cmd, unsigned long arg)
 {
-	struct gendisk *disk = bdev->bd_disk;
-	struct scsi_disk *sdkp = scsi_disk(disk);
-	struct scsi_device *sdev = sdkp->device;
 	void __user *p = compat_ptr(arg);
-	int error;
-
-	error = scsi_verify_blk_ioctl(bdev, cmd);
-	if (error < 0)
-		return error;
+	int ret;
 
-	error = scsi_ioctl_block_when_processing_errors(sdev, cmd,
-			(mode & FMODE_NDELAY) != 0);
-	if (error)
-		return error;
+	ret = sd_ioctl_common(bdev, mode, cmd, p);
+	if (ret != -ENOTTY)
+		return ret;
 
-	if (is_sed_ioctl(cmd))
-		return sed_ioctl(sdkp->opal_dev, cmd, p);
-	       
-	/* 
-	 * Let the static ioctl translation table take care of it.
-	 */
-	if (!sdev->host->hostt->compat_ioctl)
-		return -ENOIOCTLCMD; 
-	return sdev->host->hostt->compat_ioctl(sdev, cmd, p);
+	return scsi_compat_ioctl(scsi_disk(bdev->bd_disk)->device, cmd, p);
 }
 #endif
 
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index eace8886d95a..bafeaf7b9ad8 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -911,19 +911,14 @@ static int put_compat_request_table(struct compat_sg_req_info __user *o,
 #endif
 
 static long
-sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
+sg_ioctl_common(struct file *filp, Sg_device *sdp, Sg_fd *sfp,
+		unsigned int cmd_in, void __user *p)
 {
-	void __user *p = (void __user *)arg;
 	int __user *ip = p;
 	int result, val, read_only;
-	Sg_device *sdp;
-	Sg_fd *sfp;
 	Sg_request *srp;
 	unsigned long iflags;
 
-	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
-		return -ENXIO;
-
 	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
 				   "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
 	read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
@@ -1146,29 +1141,44 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
 			cmd_in, filp->f_flags & O_NDELAY);
 	if (result)
 		return result;
+
+	return -ENOIOCTLCMD;
+}
+
+static long
+sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
+{
+	void __user *p = (void __user *)arg;
+	Sg_device *sdp;
+	Sg_fd *sfp;
+	int ret;
+
+	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
+		return -ENXIO;
+
+	ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);
+	if (ret != -ENOIOCTLCMD)
+		return ret;
+
 	return scsi_ioctl(sdp->device, cmd_in, p);
 }
 
 #ifdef CONFIG_COMPAT
 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
 {
+	void __user *p = compat_ptr(arg);
 	Sg_device *sdp;
 	Sg_fd *sfp;
-	struct scsi_device *sdev;
+	int ret;
 
 	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 		return -ENXIO;
 
-	sdev = sdp->device;
-	if (sdev->host->hostt->compat_ioctl) { 
-		int ret;
-
-		ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
-
+	ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);
+	if (ret != -ENOIOCTLCMD)
 		return ret;
-	}
-	
-	return -ENOIOCTLCMD;
+
+	return scsi_compat_ioctl(sdp->device, cmd_in, p);
 }
 #endif
 
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 4664fdf75c0f..6033a886c42c 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -38,6 +38,7 @@
 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/bio.h>
+#include <linux/compat.h>
 #include <linux/string.h>
 #include <linux/errno.h>
 #include <linux/cdrom.h>
@@ -598,6 +599,55 @@ static int sr_block_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 	return ret;
 }
 
+#ifdef CONFIG_COMPAT
+static int sr_block_compat_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
+			  unsigned long arg)
+{
+	struct scsi_cd *cd = scsi_cd(bdev->bd_disk);
+	struct scsi_device *sdev = cd->device;
+	void __user *argp = compat_ptr(arg);
+	int ret;
+
+	mutex_lock(&sr_mutex);
+
+	ret = scsi_ioctl_block_when_processing_errors(sdev, cmd,
+			(mode & FMODE_NDELAY) != 0);
+	if (ret)
+		goto out;
+
+	scsi_autopm_get_device(sdev);
+
+	/*
+	 * Send SCSI addressing ioctls directly to mid level, send other
+	 * ioctls to cdrom/block level.
+	 */
+	switch (cmd) {
+	case SCSI_IOCTL_GET_IDLUN:
+	case SCSI_IOCTL_GET_BUS_NUMBER:
+		ret = scsi_compat_ioctl(sdev, cmd, argp);
+		goto put;
+	}
+
+	/*
+	 * CDROM ioctls are handled in the block layer, but
+	 * do the scsi blk ioctls here.
+	 */
+	ret = scsi_cmd_blk_ioctl(bdev, mode, cmd, argp);
+	if (ret != -ENOTTY)
+		return ret;
+
+	ret = scsi_compat_ioctl(sdev, cmd, argp);
+
+put:
+	scsi_autopm_put_device(sdev);
+
+out:
+	mutex_unlock(&sr_mutex);
+	return ret;
+
+}
+#endif
+
 static unsigned int sr_block_check_events(struct gendisk *disk,
 					  unsigned int clearing)
 {
@@ -641,12 +691,11 @@ static const struct block_device_operations sr_bdops =
 	.open		= sr_block_open,
 	.release	= sr_block_release,
 	.ioctl		= sr_block_ioctl,
+#ifdef CONFIG_COMPAT
+	.ioctl		= sr_block_compat_ioctl,
+#endif
 	.check_events	= sr_block_check_events,
 	.revalidate_disk = sr_block_revalidate_disk,
-	/* 
-	 * No compat_ioctl for now because sr_block_ioctl never
-	 * seems to pass arbitrary ioctls down to host drivers.
-	 */
 };
 
 static int sr_open(struct cdrom_device_info *cdi, int purpose)
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index 9e3fff2de83e..393f3019ccac 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -3501,7 +3501,7 @@ static int partition_tape(struct scsi_tape *STp, int size)
 
 
 /* The ioctl command */
-static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
+static long st_ioctl_common(struct file *file, unsigned int cmd_in, void __user *p)
 {
 	int i, cmd_nr, cmd_type, bt;
 	int retval = 0;
@@ -3509,7 +3509,6 @@ static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
 	struct scsi_tape *STp = file->private_data;
 	struct st_modedef *STm;
 	struct st_partstat *STps;
-	void __user *p = (void __user *)arg;
 
 	if (mutex_lock_interruptible(&STp->lock))
 		return -ERESTARTSYS;
@@ -3824,9 +3823,19 @@ static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
 	}
 	mutex_unlock(&STp->lock);
 	switch (cmd_in) {
+		case SCSI_IOCTL_STOP_UNIT:
+			/* unload */
+			retval = scsi_ioctl(STp->device, cmd_in, p);
+			if (!retval) {
+				STp->rew_at_close = 0;
+				STp->ready = ST_NO_TAPE;
+			}
+			return retval;
+
 		case SCSI_IOCTL_GET_IDLUN:
 		case SCSI_IOCTL_GET_BUS_NUMBER:
 			break;
+
 		default:
 			if ((cmd_in == SG_IO ||
 			     cmd_in == SCSI_IOCTL_SEND_COMMAND ||
@@ -3840,42 +3849,46 @@ static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
 				return i;
 			break;
 	}
-	retval = scsi_ioctl(STp->device, cmd_in, p);
-	if (!retval && cmd_in == SCSI_IOCTL_STOP_UNIT) { /* unload */
-		STp->rew_at_close = 0;
-		STp->ready = ST_NO_TAPE;
-	}
-	return retval;
+	return -ENOTTY;
 
  out:
 	mutex_unlock(&STp->lock);
 	return retval;
 }
 
+static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
+{
+	void __user *p = (void __user *)arg;
+	struct scsi_tape *STp = file->private_data;
+	int ret;
+
+	ret = st_ioctl_common(file, cmd_in, p);
+	if (ret != -ENOTTY)
+		return ret;
+
+	return scsi_ioctl(STp->device, cmd_in, p);
+}
+
 #ifdef CONFIG_COMPAT
 static long st_compat_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
 {
 	void __user *p = compat_ptr(arg);
 	struct scsi_tape *STp = file->private_data;
-	struct scsi_device *sdev = STp->device;
-	int ret = -ENOIOCTLCMD;
+	int ret;
 
 	/* argument conversion is handled using put_user_mtpos/put_user_mtget */
 	switch (cmd_in) {
-	case MTIOCTOP:
-		return st_ioctl(file, MTIOCTOP, (unsigned long)p);
 	case MTIOCPOS32:
-		return st_ioctl(file, MTIOCPOS, (unsigned long)p);
+		return st_ioctl_common(file, MTIOCPOS, p);
 	case MTIOCGET32:
-		return st_ioctl(file, MTIOCGET, (unsigned long)p);
+		return st_ioctl_common(file, MTIOCGET, p);
 	}
 
-	if (sdev->host->hostt->compat_ioctl) { 
+	ret = st_ioctl_common(file, cmd_in, p);
+	if (ret != -ENOTTY)
+		return ret;
 
-		ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
-
-	}
-	return ret;
+	return scsi_compat_ioctl(STp->device, cmd_in, p);
 }
 #endif
 
diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
index 358ea2ecf36b..ab4471f469e6 100644
--- a/fs/compat_ioctl.c
+++ b/fs/compat_ioctl.c
@@ -36,109 +36,11 @@
 
 #include "internal.h"
 
-#ifdef CONFIG_BLOCK
-#include <linux/cdrom.h>
-#include <linux/fd.h>
-#include <scsi/scsi.h>
-#include <scsi/scsi_ioctl.h>
-#include <scsi/sg.h>
-#endif
-
 #include <linux/uaccess.h>
 #include <linux/watchdog.h>
 
 #include <linux/hiddev.h>
 
-
-#include <linux/sort.h>
-
-/*
- * simple reversible transform to make our table more evenly
- * distributed after sorting.
- */
-#define XFORM(i) (((i) ^ ((i) << 27) ^ ((i) << 17)) & 0xffffffff)
-
-#define COMPATIBLE_IOCTL(cmd) XFORM((u32)cmd),
-static unsigned int ioctl_pointer[] = {
-#ifdef CONFIG_BLOCK
-/* Big S */
-COMPATIBLE_IOCTL(SCSI_IOCTL_GET_IDLUN)
-COMPATIBLE_IOCTL(SCSI_IOCTL_DOORLOCK)
-COMPATIBLE_IOCTL(SCSI_IOCTL_DOORUNLOCK)
-COMPATIBLE_IOCTL(SCSI_IOCTL_TEST_UNIT_READY)
-COMPATIBLE_IOCTL(SCSI_IOCTL_GET_BUS_NUMBER)
-COMPATIBLE_IOCTL(SCSI_IOCTL_SEND_COMMAND)
-COMPATIBLE_IOCTL(SCSI_IOCTL_PROBE_HOST)
-COMPATIBLE_IOCTL(SCSI_IOCTL_GET_PCI)
-#endif
-#ifdef CONFIG_BLOCK
-/* SG stuff */
-COMPATIBLE_IOCTL(SG_IO)
-COMPATIBLE_IOCTL(SG_GET_REQUEST_TABLE)
-COMPATIBLE_IOCTL(SG_SET_TIMEOUT)
-COMPATIBLE_IOCTL(SG_GET_TIMEOUT)
-COMPATIBLE_IOCTL(SG_EMULATED_HOST)
-COMPATIBLE_IOCTL(SG_GET_TRANSFORM)
-COMPATIBLE_IOCTL(SG_SET_RESERVED_SIZE)
-COMPATIBLE_IOCTL(SG_GET_RESERVED_SIZE)
-COMPATIBLE_IOCTL(SG_GET_SCSI_ID)
-COMPATIBLE_IOCTL(SG_SET_FORCE_LOW_DMA)
-COMPATIBLE_IOCTL(SG_GET_LOW_DMA)
-COMPATIBLE_IOCTL(SG_SET_FORCE_PACK_ID)
-COMPATIBLE_IOCTL(SG_GET_PACK_ID)
-COMPATIBLE_IOCTL(SG_GET_NUM_WAITING)
-COMPATIBLE_IOCTL(SG_SET_DEBUG)
-COMPATIBLE_IOCTL(SG_GET_SG_TABLESIZE)
-COMPATIBLE_IOCTL(SG_GET_COMMAND_Q)
-COMPATIBLE_IOCTL(SG_SET_COMMAND_Q)
-COMPATIBLE_IOCTL(SG_GET_VERSION_NUM)
-COMPATIBLE_IOCTL(SG_NEXT_CMD_LEN)
-COMPATIBLE_IOCTL(SG_SCSI_RESET)
-COMPATIBLE_IOCTL(SG_GET_REQUEST_TABLE)
-COMPATIBLE_IOCTL(SG_SET_KEEP_ORPHAN)
-COMPATIBLE_IOCTL(SG_GET_KEEP_ORPHAN)
-#endif
-};
-
-/*
- * Convert common ioctl arguments based on their command number
- *
- * Please do not add any code in here. Instead, implement
- * a compat_ioctl operation in the place that handleѕ the
- * ioctl for the native case.
- */
-static long do_ioctl_trans(unsigned int cmd,
-		 unsigned long arg, struct file *file)
-{
-	return -ENOIOCTLCMD;
-}
-
-static int compat_ioctl_check_table(unsigned int xcmd)
-{
-#ifdef CONFIG_BLOCK
-	int i;
-	const int max = ARRAY_SIZE(ioctl_pointer) - 1;
-
-	BUILD_BUG_ON(max >= (1 << 16));
-
-	/* guess initial offset into table, assuming a
-	   normalized distribution */
-	i = ((xcmd >> 16) * max) >> 16;
-
-	/* do linear search up first, until greater or equal */
-	while (ioctl_pointer[i] < xcmd && i < max)
-		i++;
-
-	/* then do linear search down */
-	while (ioctl_pointer[i] > xcmd && i > 0)
-		i--;
-
-	return ioctl_pointer[i] == xcmd;
-#else
-	return 0;
-#endif
-}
-
 COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
 		       compat_ulong_t, arg32)
 {
@@ -216,19 +118,9 @@ COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
 				goto out_fput;
 		}
 
-		if (!f.file->f_op->unlocked_ioctl)
-			goto do_ioctl;
-		break;
-	}
-
-	if (compat_ioctl_check_table(XFORM(cmd)))
-		goto found_handler;
-
-	error = do_ioctl_trans(cmd, arg, f.file);
-	if (error == -ENOIOCTLCMD)
 		error = -ENOTTY;
-
-	goto out_fput;
+		goto out_fput;
+	}
 
  found_handler:
 	arg = (unsigned long)compat_ptr(arg);
@@ -239,23 +131,3 @@ COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
  out:
 	return error;
 }
-
-static int __init init_sys32_ioctl_cmp(const void *p, const void *q)
-{
-	unsigned int a, b;
-	a = *(unsigned int *)p;
-	b = *(unsigned int *)q;
-	if (a > b)
-		return 1;
-	if (a < b)
-		return -1;
-	return 0;
-}
-
-static int __init init_sys32_ioctl(void)
-{
-	sort(ioctl_pointer, ARRAY_SIZE(ioctl_pointer), sizeof(*ioctl_pointer),
-		init_sys32_ioctl_cmp, NULL);
-	return 0;
-}
-__initcall(init_sys32_ioctl);
-- 
2.20.0

[PATCH v3 14/22] compat_ioctl: move sys_compat_ioctl() to ioctl.c

[Arnd Bergmann]

The rest of the fs/compat_ioctl.c file is no longer useful now,
so move the actual syscall as planned.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/scsi/sr.c |   2 +-
 fs/Makefile       |   2 +-
 fs/compat_ioctl.c | 133 ----------------------------------------------
 fs/ioctl.c        |  90 +++++++++++++++++++++++++++++++
 4 files changed, 92 insertions(+), 135 deletions(-)
 delete mode 100644 fs/compat_ioctl.c

diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 6033a886c42c..f1e7aab00ce3 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -634,7 +634,7 @@ static int sr_block_compat_ioctl(struct block_device *bdev, fmode_t mode, unsign
 	 */
 	ret = scsi_cmd_blk_ioctl(bdev, mode, cmd, argp);
 	if (ret != -ENOTTY)
-		return ret;
+		goto put;
 
 	ret = scsi_compat_ioctl(sdev, cmd, argp);
 
diff --git a/fs/Makefile b/fs/Makefile
index 1148c555c4d3..98be354fdb61 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -37,7 +37,7 @@ obj-$(CONFIG_FS_DAX)		+= dax.o
 obj-$(CONFIG_FS_ENCRYPTION)	+= crypto/
 obj-$(CONFIG_FS_VERITY)		+= verity/
 obj-$(CONFIG_FILE_LOCKING)      += locks.o
-obj-$(CONFIG_COMPAT)		+= compat.o compat_ioctl.o
+obj-$(CONFIG_COMPAT)		+= compat.o
 obj-$(CONFIG_BINFMT_AOUT)	+= binfmt_aout.o
 obj-$(CONFIG_BINFMT_EM86)	+= binfmt_em86.o
 obj-$(CONFIG_BINFMT_MISC)	+= binfmt_misc.o
diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
deleted file mode 100644
index ab4471f469e6..000000000000
--- a/fs/compat_ioctl.c
+++ /dev/null
@@ -1,133 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * ioctl32.c: Conversion between 32bit and 64bit native ioctls.
- *
- * Copyright (C) 1997-2000  Jakub Jelinek  (jakub@redhat.com)
- * Copyright (C) 1998  Eddie C. Dost  (ecd@skynet.be)
- * Copyright (C) 2001,2002  Andi Kleen, SuSE Labs 
- * Copyright (C) 2003       Pavel Machek (pavel@ucw.cz)
- *
- * These routines maintain argument size conversion between 32bit and 64bit
- * ioctls.
- */
-
-#include <linux/types.h>
-#include <linux/compat.h>
-#include <linux/kernel.h>
-#include <linux/capability.h>
-#include <linux/compiler.h>
-#include <linux/sched.h>
-#include <linux/smp.h>
-#include <linux/ioctl.h>
-#include <linux/if.h>
-#include <linux/raid/md_u.h>
-#include <linux/falloc.h>
-#include <linux/file.h>
-#include <linux/ppp-ioctl.h>
-#include <linux/if_pppox.h>
-#include <linux/tty.h>
-#include <linux/vt_kern.h>
-#include <linux/blkdev.h>
-#include <linux/serial.h>
-#include <linux/ctype.h>
-#include <linux/syscalls.h>
-#include <linux/gfp.h>
-#include <linux/cec.h>
-
-#include "internal.h"
-
-#include <linux/uaccess.h>
-#include <linux/watchdog.h>
-
-#include <linux/hiddev.h>
-
-COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
-		       compat_ulong_t, arg32)
-{
-	unsigned long arg = arg32;
-	struct fd f = fdget(fd);
-	int error = -EBADF;
-	if (!f.file)
-		goto out;
-
-	/* RED-PEN how should LSM module know it's handling 32bit? */
-	error = security_file_ioctl(f.file, cmd, arg);
-	if (error)
-		goto out_fput;
-
-	switch (cmd) {
-	/* these are never seen by ->ioctl(), no argument or int argument */
-	case FIOCLEX:
-	case FIONCLEX:
-	case FIFREEZE:
-	case FITHAW:
-	case FICLONE:
-		goto do_ioctl;
-	/* these are never seen by ->ioctl(), pointer argument */
-	case FIONBIO:
-	case FIOASYNC:
-	case FIOQSIZE:
-	case FS_IOC_FIEMAP:
-	case FIGETBSZ:
-	case FICLONERANGE:
-	case FIDEDUPERANGE:
-		goto found_handler;
-	/*
-	 * The next group is the stuff handled inside file_ioctl().
-	 * For regular files these never reach ->ioctl(); for
-	 * devices, sockets, etc. they do and one (FIONREAD) is
-	 * even accepted in some cases.  In all those cases
-	 * argument has the same type, so we can handle these
-	 * here, shunting them towards do_vfs_ioctl().
-	 * ->compat_ioctl() will never see any of those.
-	 */
-	/* pointer argument, never actually handled by ->ioctl() */
-	case FIBMAP:
-		goto found_handler;
-	/* handled by some ->ioctl(); always a pointer to int */
-	case FIONREAD:
-		goto found_handler;
-	/* these get messy on amd64 due to alignment differences */
-#if defined(CONFIG_X86_64)
-	case FS_IOC_RESVSP_32:
-	case FS_IOC_RESVSP64_32:
-		error = compat_ioctl_preallocate(f.file, 0, compat_ptr(arg));
-		goto out_fput;
-	case FS_IOC_UNRESVSP_32:
-	case FS_IOC_UNRESVSP64_32:
-		error = compat_ioctl_preallocate(f.file, FALLOC_FL_PUNCH_HOLE,
-				compat_ptr(arg));
-		goto out_fput;
-	case FS_IOC_ZERO_RANGE_32:
-		error = compat_ioctl_preallocate(f.file, FALLOC_FL_ZERO_RANGE,
-				compat_ptr(arg));
-		goto out_fput;
-#else
-	case FS_IOC_RESVSP:
-	case FS_IOC_RESVSP64:
-	case FS_IOC_UNRESVSP:
-	case FS_IOC_UNRESVSP64:
-	case FS_IOC_ZERO_RANGE:
-		goto found_handler;
-#endif
-
-	default:
-		if (f.file->f_op->compat_ioctl) {
-			error = f.file->f_op->compat_ioctl(f.file, cmd, arg);
-			if (error != -ENOIOCTLCMD)
-				goto out_fput;
-		}
-
-		error = -ENOTTY;
-		goto out_fput;
-	}
-
- found_handler:
-	arg = (unsigned long)compat_ptr(arg);
- do_ioctl:
-	error = do_vfs_ioctl(f.file, fd, cmd, arg);
- out_fput:
-	fdput(f);
- out:
-	return error;
-}
diff --git a/fs/ioctl.c b/fs/ioctl.c
index 2f5e4e5b97e1..8f22f7817edb 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -788,4 +788,94 @@ long compat_ptr_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	return file->f_op->unlocked_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
 }
 EXPORT_SYMBOL(compat_ptr_ioctl);
+
+COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
+		       compat_ulong_t, arg32)
+{
+	unsigned long arg = arg32;
+	struct fd f = fdget(fd);
+	int error = -EBADF;
+	if (!f.file)
+		goto out;
+
+	/* RED-PEN how should LSM module know it's handling 32bit? */
+	error = security_file_ioctl(f.file, cmd, arg);
+	if (error)
+		goto out_fput;
+
+	switch (cmd) {
+	/* these are never seen by ->ioctl(), no argument or int argument */
+	case FIOCLEX:
+	case FIONCLEX:
+	case FIFREEZE:
+	case FITHAW:
+	case FICLONE:
+		goto do_ioctl;
+	/* these are never seen by ->ioctl(), pointer argument */
+	case FIONBIO:
+	case FIOASYNC:
+	case FIOQSIZE:
+	case FS_IOC_FIEMAP:
+	case FIGETBSZ:
+	case FICLONERANGE:
+	case FIDEDUPERANGE:
+		goto found_handler;
+	/*
+	 * The next group is the stuff handled inside file_ioctl().
+	 * For regular files these never reach ->ioctl(); for
+	 * devices, sockets, etc. they do and one (FIONREAD) is
+	 * even accepted in some cases.  In all those cases
+	 * argument has the same type, so we can handle these
+	 * here, shunting them towards do_vfs_ioctl().
+	 * ->compat_ioctl() will never see any of those.
+	 */
+	/* pointer argument, never actually handled by ->ioctl() */
+	case FIBMAP:
+		goto found_handler;
+	/* handled by some ->ioctl(); always a pointer to int */
+	case FIONREAD:
+		goto found_handler;
+	/* these get messy on amd64 due to alignment differences */
+#if defined(CONFIG_X86_64)
+	case FS_IOC_RESVSP_32:
+	case FS_IOC_RESVSP64_32:
+		error = compat_ioctl_preallocate(f.file, 0, compat_ptr(arg));
+		goto out_fput;
+	case FS_IOC_UNRESVSP_32:
+	case FS_IOC_UNRESVSP64_32:
+		error = compat_ioctl_preallocate(f.file, FALLOC_FL_PUNCH_HOLE,
+				compat_ptr(arg));
+		goto out_fput;
+	case FS_IOC_ZERO_RANGE_32:
+		error = compat_ioctl_preallocate(f.file, FALLOC_FL_ZERO_RANGE,
+				compat_ptr(arg));
+		goto out_fput;
+#else
+	case FS_IOC_RESVSP:
+	case FS_IOC_RESVSP64:
+	case FS_IOC_UNRESVSP:
+	case FS_IOC_UNRESVSP64:
+	case FS_IOC_ZERO_RANGE:
+		goto found_handler;
+#endif
+
+	default:
+		if (f.file->f_op->compat_ioctl) {
+			error = f.file->f_op->compat_ioctl(f.file, cmd, arg);
+			if (error != -ENOIOCTLCMD)
+				goto out_fput;
+		}
+		error = -ENOTTY;
+		goto out_fput;
+	}
+
+ found_handler:
+	arg = (unsigned long)compat_ptr(arg);
+ do_ioctl:
+	error = do_vfs_ioctl(f.file, fd, cmd, arg);
+ out_fput:
+	fdput(f);
+ out:
+	return error;
+}
 #endif
-- 
2.20.0

[PATCH v3 15/22] compat_ioctl: simplify the implementation

[Arnd Bergmann]

Now that both native and compat ioctl syscalls are
in the same file, a couple of simplifications can
be made, bringing the implementation closer together:

- do_vfs_ioctl(), ioctl_preallocate(), and compat_ioctl_preallocate()
  can become static, allowing the compiler to optimize better

- slightly update the coding style for consistency between
  the functions.

- rather than listing each command in two switch statements
  for the compat case, just call a single function that has
  all the common commands.

As a side-effect, FS_IOC_RESVSP/FS_IOC_RESVSP64 are now available
to x86 compat tasks, along with FS_IOC_RESVSP_32/FS_IOC_RESVSP64_32.
This is harmless for i386 emulation, and can be considered a bugfix
for x32 emulation, which never supported these in the past.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 fs/internal.h          |   6 --
 fs/ioctl.c             | 157 +++++++++++++++++------------------------
 include/linux/falloc.h |   2 -
 include/linux/fs.h     |   4 --
 4 files changed, 64 insertions(+), 105 deletions(-)

diff --git a/fs/internal.h b/fs/internal.h
index 4a7da1df573d..d46247850ad7 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -180,11 +180,5 @@ extern void mnt_pin_kill(struct mount *m);
  */
 extern const struct dentry_operations ns_dentry_operations;
 
-/*
- * fs/ioctl.c
- */
-extern int do_vfs_ioctl(struct file *file, unsigned int fd, unsigned int cmd,
-		    unsigned long arg);
-
 /* direct-io.c: */
 int sb_init_dio_done_wq(struct super_block *sb);
diff --git a/fs/ioctl.c b/fs/ioctl.c
index 8f22f7817edb..7c9a5df5a597 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -467,7 +467,7 @@ EXPORT_SYMBOL(generic_block_fiemap);
  * Only the l_start, l_len and l_whence fields of the 'struct space_resv'
  * are used here, rest are ignored.
  */
-int ioctl_preallocate(struct file *filp, int mode, void __user *argp)
+static int ioctl_preallocate(struct file *filp, int mode, void __user *argp)
 {
 	struct inode *inode = file_inode(filp);
 	struct space_resv sr;
@@ -495,8 +495,8 @@ int ioctl_preallocate(struct file *filp, int mode, void __user *argp)
 /* on ia32 l_start is on a 32-bit boundary */
 #if defined CONFIG_COMPAT && defined(CONFIG_X86_64)
 /* just account for different alignment */
-int compat_ioctl_preallocate(struct file *file, int mode,
-				struct space_resv_32 __user *argp)
+static int compat_ioctl_preallocate(struct file *file, int mode,
+				    struct space_resv_32 __user *argp)
 {
 	struct inode *inode = file_inode(file);
 	struct space_resv_32 sr;
@@ -521,11 +521,9 @@ int compat_ioctl_preallocate(struct file *file, int mode,
 }
 #endif
 
-static int file_ioctl(struct file *filp, unsigned int cmd,
-		unsigned long arg)
+static int file_ioctl(struct file *filp, unsigned int cmd, int __user *p)
 {
 	struct inode *inode = file_inode(filp);
-	int __user *p = (int __user *)arg;
 
 	switch (cmd) {
 	case FIBMAP:
@@ -542,7 +540,7 @@ static int file_ioctl(struct file *filp, unsigned int cmd,
 		return ioctl_preallocate(filp, FALLOC_FL_ZERO_RANGE, p);
 	}
 
-	return vfs_ioctl(filp, cmd, arg);
+	return -ENOIOCTLCMD;
 }
 
 static int ioctl_fionbio(struct file *filp, int __user *argp)
@@ -661,53 +659,48 @@ static int ioctl_file_dedupe_range(struct file *file,
 }
 
 /*
- * When you add any new common ioctls to the switches above and below
- * please update compat_sys_ioctl() too.
- *
  * do_vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d.
  * It's just a simple helper for sys_ioctl and compat_sys_ioctl.
+ *
+ * When you add any new common ioctls to the switches above and below,
+ * please ensure they have compatible arguments in compat mode.
  */
-int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
-	     unsigned long arg)
+static int do_vfs_ioctl(struct file *filp, unsigned int fd,
+			unsigned int cmd, unsigned long arg)
 {
-	int error = 0;
 	void __user *argp = (void __user *)arg;
 	struct inode *inode = file_inode(filp);
 
 	switch (cmd) {
 	case FIOCLEX:
 		set_close_on_exec(fd, 1);
-		break;
+		return 0;
 
 	case FIONCLEX:
 		set_close_on_exec(fd, 0);
-		break;
+		return 0;
 
 	case FIONBIO:
-		error = ioctl_fionbio(filp, argp);
-		break;
+		return ioctl_fionbio(filp, argp);
 
 	case FIOASYNC:
-		error = ioctl_fioasync(fd, filp, argp);
-		break;
+		return ioctl_fioasync(fd, filp, argp);
 
 	case FIOQSIZE:
 		if (S_ISDIR(inode->i_mode) || S_ISREG(inode->i_mode) ||
 		    S_ISLNK(inode->i_mode)) {
 			loff_t res = inode_get_bytes(inode);
-			error = copy_to_user(argp, &res, sizeof(res)) ?
-					-EFAULT : 0;
-		} else
-			error = -ENOTTY;
-		break;
+			return copy_to_user(argp, &res, sizeof(res)) ?
+					    -EFAULT : 0;
+		}
+
+		return -ENOTTY;
 
 	case FIFREEZE:
-		error = ioctl_fsfreeze(filp);
-		break;
+		return ioctl_fsfreeze(filp);
 
 	case FITHAW:
-		error = ioctl_fsthaw(filp);
-		break;
+		return ioctl_fsthaw(filp);
 
 	case FS_IOC_FIEMAP:
 		return ioctl_fiemap(filp, argp);
@@ -716,6 +709,7 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
 		/* anon_bdev filesystems may not have a block size */
 		if (!inode->i_sb->s_blocksize)
 			return -EINVAL;
+
 		return put_user(inode->i_sb->s_blocksize, (int __user *)argp);
 
 	case FICLONE:
@@ -729,24 +723,30 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
 
 	default:
 		if (S_ISREG(inode->i_mode))
-			error = file_ioctl(filp, cmd, arg);
-		else
-			error = vfs_ioctl(filp, cmd, arg);
+			return file_ioctl(filp, cmd, argp);
 		break;
 	}
-	return error;
+
+	return -ENOIOCTLCMD;
 }
 
 int ksys_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
 {
-	int error;
 	struct fd f = fdget(fd);
+	int error;
 
 	if (!f.file)
 		return -EBADF;
+
 	error = security_file_ioctl(f.file, cmd, arg);
-	if (!error)
-		error = do_vfs_ioctl(f.file, fd, cmd, arg);
+	if (error)
+		goto out;
+
+	error = do_vfs_ioctl(f.file, fd, cmd, arg);
+	if (error == -ENOIOCTLCMD)
+		error = vfs_ioctl(f.file, cmd, arg);
+
+out:
 	fdput(f);
 	return error;
 }
@@ -790,92 +790,63 @@ long compat_ptr_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 EXPORT_SYMBOL(compat_ptr_ioctl);
 
 COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
-		       compat_ulong_t, arg32)
+		       compat_ulong_t, arg)
 {
-	unsigned long arg = arg32;
 	struct fd f = fdget(fd);
-	int error = -EBADF;
+	int error;
+
 	if (!f.file)
-		goto out;
+		return -EBADF;
 
 	/* RED-PEN how should LSM module know it's handling 32bit? */
 	error = security_file_ioctl(f.file, cmd, arg);
 	if (error)
-		goto out_fput;
+		goto out;
 
 	switch (cmd) {
-	/* these are never seen by ->ioctl(), no argument or int argument */
-	case FIOCLEX:
-	case FIONCLEX:
-	case FIFREEZE:
-	case FITHAW:
+	/* FICLONE takes an int argument, so don't use compat_ptr() */
 	case FICLONE:
-		goto do_ioctl;
-	/* these are never seen by ->ioctl(), pointer argument */
-	case FIONBIO:
-	case FIOASYNC:
-	case FIOQSIZE:
-	case FS_IOC_FIEMAP:
-	case FIGETBSZ:
-	case FICLONERANGE:
-	case FIDEDUPERANGE:
-		goto found_handler;
-	/*
-	 * The next group is the stuff handled inside file_ioctl().
-	 * For regular files these never reach ->ioctl(); for
-	 * devices, sockets, etc. they do and one (FIONREAD) is
-	 * even accepted in some cases.  In all those cases
-	 * argument has the same type, so we can handle these
-	 * here, shunting them towards do_vfs_ioctl().
-	 * ->compat_ioctl() will never see any of those.
-	 */
-	/* pointer argument, never actually handled by ->ioctl() */
-	case FIBMAP:
-		goto found_handler;
-	/* handled by some ->ioctl(); always a pointer to int */
-	case FIONREAD:
-		goto found_handler;
-	/* these get messy on amd64 due to alignment differences */
+		error = ioctl_file_clone(f.file, arg, 0, 0, 0);
+		break;
+
 #if defined(CONFIG_X86_64)
+	/* these get messy on amd64 due to alignment differences */
 	case FS_IOC_RESVSP_32:
 	case FS_IOC_RESVSP64_32:
 		error = compat_ioctl_preallocate(f.file, 0, compat_ptr(arg));
-		goto out_fput;
+		break;
 	case FS_IOC_UNRESVSP_32:
 	case FS_IOC_UNRESVSP64_32:
 		error = compat_ioctl_preallocate(f.file, FALLOC_FL_PUNCH_HOLE,
 				compat_ptr(arg));
-		goto out_fput;
+		break;
 	case FS_IOC_ZERO_RANGE_32:
 		error = compat_ioctl_preallocate(f.file, FALLOC_FL_ZERO_RANGE,
 				compat_ptr(arg));
-		goto out_fput;
-#else
-	case FS_IOC_RESVSP:
-	case FS_IOC_RESVSP64:
-	case FS_IOC_UNRESVSP:
-	case FS_IOC_UNRESVSP64:
-	case FS_IOC_ZERO_RANGE:
-		goto found_handler;
+		break;
 #endif
 
+	/*
+	 * everything else in do_vfs_ioctl() takes either a compatible
+	 * pointer argument or no argument -- call it with a modified
+	 * argument.
+	 */
 	default:
-		if (f.file->f_op->compat_ioctl) {
+		error = do_vfs_ioctl(f.file, fd, cmd,
+				     (unsigned long)compat_ptr(arg));
+		if (error != -ENOIOCTLCMD)
+			break;
+
+		if (f.file->f_op->compat_ioctl)
 			error = f.file->f_op->compat_ioctl(f.file, cmd, arg);
-			if (error != -ENOIOCTLCMD)
-				goto out_fput;
-		}
-		error = -ENOTTY;
-		goto out_fput;
+		if (error == -ENOIOCTLCMD)
+			error = -ENOTTY;
+		break;
 	}
 
- found_handler:
-	arg = (unsigned long)compat_ptr(arg);
- do_ioctl:
-	error = do_vfs_ioctl(f.file, fd, cmd, arg);
- out_fput:
-	fdput(f);
  out:
+	fdput(f);
+
 	return error;
 }
 #endif
diff --git a/include/linux/falloc.h b/include/linux/falloc.h
index 8bf3d79f3e82..f3f0b97b1675 100644
--- a/include/linux/falloc.h
+++ b/include/linux/falloc.h
@@ -51,8 +51,6 @@ struct space_resv_32 {
 #define FS_IOC_UNRESVSP64_32	_IOW ('X', 43, struct space_resv_32)
 #define FS_IOC_ZERO_RANGE_32	_IOW ('X', 57, struct space_resv_32)
 
-int compat_ioctl_preallocate(struct file *, int, struct space_resv_32 __user *);
-
 #endif
 
 #endif /* _FALLOC_H_ */
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 98e0349adb52..daf570bca42a 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2552,10 +2552,6 @@ extern int finish_open(struct file *file, struct dentry *dentry,
 			int (*open)(struct inode *, struct file *));
 extern int finish_no_open(struct file *file, struct dentry *dentry);
 
-/* fs/ioctl.c */
-
-extern int ioctl_preallocate(struct file *filp, int mode, void __user *argp);
-
 /* fs/dcache.c */
 extern void __init vfs_caches_init_early(void);
 extern void __init vfs_caches_init(void);
-- 
2.20.0

Re: [PATCH v3 13/22] compat_ioctl: scsi: move ioctl handling into drivers

[Stefan Hajnoczi]

[-- Attachment #1: Type: text/plain, Size: 1163 bytes --]

On Thu, Jan 02, 2020 at 03:55:31PM +0100, Arnd Bergmann wrote:
> Each driver calling scsi_ioctl() gets an equivalent compat_ioctl()
> handler that implements the same commands by calling scsi_compat_ioctl().
> 
> The scsi_cmd_ioctl() and scsi_cmd_blk_ioctl() functions are compatible
> at this point, so any driver that calls those can do so for both native
> and compat mode, with the argument passed through compat_ptr().
> 
> With this, we can remove the entries from fs/compat_ioctl.c.  The new
> code is larger, but should be easier to maintain and keep updated with
> newly added commands.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  drivers/block/virtio_blk.c |   3 +
>  drivers/scsi/ch.c          |   9 ++-
>  drivers/scsi/sd.c          |  50 ++++++--------
>  drivers/scsi/sg.c          |  44 ++++++++-----
>  drivers/scsi/sr.c          |  57 ++++++++++++++--
>  drivers/scsi/st.c          |  51 ++++++++------
>  fs/compat_ioctl.c          | 132 +------------------------------------
>  7 files changed, 142 insertions(+), 204 deletions(-)

virtio_blk.c changes:

Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

Re: [GIT PULL v3 00/27] block, scsi: final compat_ioctl cleanup

[Arnd Bergmann]

On Thu, Jan 2, 2020 at 3:56 PM Arnd Bergmann <arnd@arndb.de> wrote:
>
> Hi Martin, James,
>
> If this version seems ok to everyone, please pull into
> the scsi tree.

It seems I slightly messed up the Cc list here, in case some of you are
missing patches, the full series (22 patches, not 27) is mirrored at
https://lore.kernel.org/lkml/20200102145552.1853992-1-arnd@arndb.de/T/
as well.

         Arnd

Re: [GIT PULL v3 00/27] block, scsi: final compat_ioctl cleanup

[Ben Hutchings]

On Thu, 2020-01-02 at 15:55 +0100, Arnd Bergmann wrote:
[...]
> Changes since v2:
> - Rebase to v5.5-rc4, which contains the earlier bugfixes
> - Fix sr_block_compat_ioctl() error handling bug found by
>   Ben Hutchings
[...]

Unfortunately that fix was squashed into "compat_ioctl: move
sys_compat_ioctl() to ioctl.c" whereas it belongs in "compat_ioctl:
scsi: move ioctl handling into drivers".

If you decide to rebase again, you can add my Reviewed-by to all
patches.

Ben.

-- 
Ben Hutchings, Software Developer                         Codethink Ltd
https://www.codethink.co.uk/                 Dale House, 35 Dale Street
                                     Manchester, M1 2HF, United Kingdom

Re: [GIT PULL v3 00/27] block, scsi: final compat_ioctl cleanup

[Martin K. Petersen]

Arnd,

> If this version seems ok to everyone, please pull into the scsi tree.

Looks good to me. Please address Ben's comment and I'll pull it in.

-- 
Martin K. Petersen	Oracle Linux Engineering

Re: [GIT PULL v3 00/27] block, scsi: final compat_ioctl cleanup

[Arnd Bergmann]

On Fri, Jan 3, 2020 at 1:22 AM Ben Hutchings
<ben.hutchings@codethink.co.uk> wrote:
>
> On Thu, 2020-01-02 at 15:55 +0100, Arnd Bergmann wrote:
> [...]
> > Changes since v2:
> > - Rebase to v5.5-rc4, which contains the earlier bugfixes
> > - Fix sr_block_compat_ioctl() error handling bug found by
> >   Ben Hutchings
> [...]
>
> Unfortunately that fix was squashed into "compat_ioctl: move
> sys_compat_ioctl() to ioctl.c" whereas it belongs in "compat_ioctl:
> scsi: move ioctl handling into drivers".

Fixed now.

> If you decide to rebase again, you can add my Reviewed-by to all
> patches.

Done, and pushed out to the same tag as before

https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/
block-ioctl-cleanup-5.6

Thank you again for the careful review!

Martin, please pull the URL above to get the latest version, the top commit
is 8ce156deca718 ("Documentation: document ioctl interfaces better").

       Arnd

Re: [PATCH v3 13/22] compat_ioctl: scsi: move ioctl handling into drivers

[Johannes Hirte]

On 2020 Jan 02, Arnd Bergmann wrote:
> Each driver calling scsi_ioctl() gets an equivalent compat_ioctl()
> handler that implements the same commands by calling scsi_compat_ioctl().
> 
> The scsi_cmd_ioctl() and scsi_cmd_blk_ioctl() functions are compatible
> at this point, so any driver that calls those can do so for both native
> and compat mode, with the argument passed through compat_ptr().
> 
> With this, we can remove the entries from fs/compat_ioctl.c.  The new
> code is larger, but should be easier to maintain and keep updated with
> newly added commands.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  drivers/block/virtio_blk.c |   3 +
>  drivers/scsi/ch.c          |   9 ++-
>  drivers/scsi/sd.c          |  50 ++++++--------
>  drivers/scsi/sg.c          |  44 ++++++++-----
>  drivers/scsi/sr.c          |  57 ++++++++++++++--
>  drivers/scsi/st.c          |  51 ++++++++------
>  fs/compat_ioctl.c          | 132 +------------------------------------
>  7 files changed, 142 insertions(+), 204 deletions(-)
> 

This breaks libcdio. cd-info now results in:

cd-info version 2.1.0 x86_64-pc-linux-gnu
Copyright (c) 2003-2005, 2007-2008, 2011-2015, 2017 R. Bernstein
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.
CD location   : /dev/cdrom
CD driver name: GNU/Linux
   access mode: IOCTL

Error in getting drive hardware properties
Error in getting drive reading properties
Error in getting drive writing properties
__________________________________

Disc mode is listed as: CD-DA
++ WARN: error in ioctl CDROMREADTOCHDR: Bad address

cd-info: Can't get first track number. I give up.


-- 
Regards,
  Johannes Hirte

Re: [PATCH v3 13/22] compat_ioctl: scsi: move ioctl handling into drivers

[Arnd Bergmann]

On Wed, Feb 12, 2020 at 10:15 PM Johannes Hirte
<johannes.hirte@datenkhaos.de> wrote:
>
> On 2020 Jan 02, Arnd Bergmann wrote:

>
> Error in getting drive hardware properties
> Error in getting drive reading properties
> Error in getting drive writing properties
> __________________________________
>
> Disc mode is listed as: CD-DA
> ++ WARN: error in ioctl CDROMREADTOCHDR: Bad address
>
> cd-info: Can't get first track number. I give up.

Right, there was also a report about breaking the Fedora installer,
see https://bugzilla.redhat.com/show_bug.cgi?id=1801353

There is a preliminary patch that should fix this, I'll post a
version with more references tomorrow:
https://www.happyassassin.net/temp/0001-Replace-.ioctl-with-.compat_ioctl-in-three-appropria.patch

      Arnd

Re: [PATCH v3 13/22] compat_ioctl: scsi: move ioctl handling into drivers

[Johannes Hirte]

On 2020 Feb 12, Arnd Bergmann wrote:
> On Wed, Feb 12, 2020 at 10:15 PM Johannes Hirte
> <johannes.hirte@datenkhaos.de> wrote:
> >
> > On 2020 Jan 02, Arnd Bergmann wrote:
> 
> >
> > Error in getting drive hardware properties
> > Error in getting drive reading properties
> > Error in getting drive writing properties
> > __________________________________
> >
> > Disc mode is listed as: CD-DA
> > ++ WARN: error in ioctl CDROMREADTOCHDR: Bad address
> >
> > cd-info: Can't get first track number. I give up.
> 
> Right, there was also a report about breaking the Fedora installer,
> see https://bugzilla.redhat.com/show_bug.cgi?id=1801353
> 
> There is a preliminary patch that should fix this, I'll post a
> version with more references tomorrow:
> https://www.happyassassin.net/temp/0001-Replace-.ioctl-with-.compat_ioctl-in-three-appropria.patch

Yes, I can confirm that the patch fix it.

-- 
Regards,
  Johannes Hirte