[PATCH v2 18/27] compat_ioctl: scsi: move ioctl handling into drivers

From: Arnd Bergmann
Date: Tue Dec 17 2019 - 17:19:39 EST

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@xxxxxxxx>
---
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 handleÑ 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