Revision 5b77e95dd7790ff6c8fbf1cd8d0104ebed818a03 authored by Alexander Potapenko on 02 April 2019, 11:28:13 UTC, committed by Ingo Molnar on 06 April 2019, 07:52:02 UTC
There's a number of problems with how arch/x86/include/asm/bitops.h is currently using assembly constraints for the memory region bitops are modifying: 1) Use memory clobber in bitops that touch arbitrary memory Certain bit operations that read/write bits take a base pointer and an arbitrarily large offset to address the bit relative to that base. Inline assembly constraints aren't expressive enough to tell the compiler that the assembly directive is going to touch a specific memory location of unknown size, therefore we have to use the "memory" clobber to indicate that the assembly is going to access memory locations other than those listed in the inputs/outputs. To indicate that BTR/BTS instructions don't necessarily touch the first sizeof(long) bytes of the argument, we also move the address to assembly inputs. This particular change leads to size increase of 124 kernel functions in a defconfig build. For some of them the diff is in NOP operations, other end up re-reading values from memory and may potentially slow down the execution. But without these clobbers the compiler is free to cache the contents of the bitmaps and use them as if they weren't changed by the inline assembly. 2) Use byte-sized arguments for operations touching single bytes. Passing a long value to ANDB/ORB/XORB instructions makes the compiler treat sizeof(long) bytes as being clobbered, which isn't the case. This may theoretically lead to worse code in the case of heavy optimization. Practical impact: I've built a defconfig kernel and looked through some of the functions generated by GCC 7.3.0 with and without this clobber, and didn't spot any miscompilations. However there is a (trivial) theoretical case where this code leads to miscompilation: https://lkml.org/lkml/2019/3/28/393 using just GCC 8.3.0 with -O2. It isn't hard to imagine someone writes such a function in the kernel someday. So the primary motivation is to fix an existing misuse of the asm directive, which happens to work in certain configurations now, but isn't guaranteed to work under different circumstances. [ --mingo: Added -stable tag because defconfig only builds a fraction of the kernel and the trivial testcase looks normal enough to be used in existing or in-development code. ] Signed-off-by: Alexander Potapenko <glider@google.com> Cc: <stable@vger.kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: James Y Knight <jyknight@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20190402112813.193378-1-glider@google.com [ Edited the changelog, tidied up one of the defines. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
1 parent faa3604
scsi_ioctl.c
/*
* Copyright (C) 2001 Jens Axboe <axboe@suse.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
*
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public Licens
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
*
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/capability.h>
#include <linux/completion.h>
#include <linux/cdrom.h>
#include <linux/ratelimit.h>
#include <linux/slab.h>
#include <linux/times.h>
#include <linux/uio.h>
#include <linux/uaccess.h>
#include <scsi/scsi.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/scsi_cmnd.h>
struct blk_cmd_filter {
unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
};
static struct blk_cmd_filter blk_default_cmd_filter;
/* Command group 3 is reserved and should never be used. */
const unsigned char scsi_command_size_tbl[8] =
{
6, 10, 10, 12,
16, 12, 10, 10
};
EXPORT_SYMBOL(scsi_command_size_tbl);
#include <scsi/sg.h>
static int sg_get_version(int __user *p)
{
static const int sg_version_num = 30527;
return put_user(sg_version_num, p);
}
static int scsi_get_idlun(struct request_queue *q, int __user *p)
{
return put_user(0, p);
}
static int scsi_get_bus(struct request_queue *q, int __user *p)
{
return put_user(0, p);
}
static int sg_get_timeout(struct request_queue *q)
{
return jiffies_to_clock_t(q->sg_timeout);
}
static int sg_set_timeout(struct request_queue *q, int __user *p)
{
int timeout, err = get_user(timeout, p);
if (!err)
q->sg_timeout = clock_t_to_jiffies(timeout);
return err;
}
static int max_sectors_bytes(struct request_queue *q)
{
unsigned int max_sectors = queue_max_sectors(q);
max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
return max_sectors << 9;
}
static int sg_get_reserved_size(struct request_queue *q, int __user *p)
{
int val = min_t(int, q->sg_reserved_size, max_sectors_bytes(q));
return put_user(val, p);
}
static int sg_set_reserved_size(struct request_queue *q, int __user *p)
{
int size, err = get_user(size, p);
if (err)
return err;
if (size < 0)
return -EINVAL;
q->sg_reserved_size = min(size, max_sectors_bytes(q));
return 0;
}
/*
* will always return that we are ATAPI even for a real SCSI drive, I'm not
* so sure this is worth doing anything about (why would you care??)
*/
static int sg_emulated_host(struct request_queue *q, int __user *p)
{
return put_user(1, p);
}
static void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter)
{
/* Basic read-only commands */
__set_bit(TEST_UNIT_READY, filter->read_ok);
__set_bit(REQUEST_SENSE, filter->read_ok);
__set_bit(READ_6, filter->read_ok);
__set_bit(READ_10, filter->read_ok);
__set_bit(READ_12, filter->read_ok);
__set_bit(READ_16, filter->read_ok);
__set_bit(READ_BUFFER, filter->read_ok);
__set_bit(READ_DEFECT_DATA, filter->read_ok);
__set_bit(READ_CAPACITY, filter->read_ok);
__set_bit(READ_LONG, filter->read_ok);
__set_bit(INQUIRY, filter->read_ok);
__set_bit(MODE_SENSE, filter->read_ok);
__set_bit(MODE_SENSE_10, filter->read_ok);
__set_bit(LOG_SENSE, filter->read_ok);
__set_bit(START_STOP, filter->read_ok);
__set_bit(GPCMD_VERIFY_10, filter->read_ok);
__set_bit(VERIFY_16, filter->read_ok);
__set_bit(REPORT_LUNS, filter->read_ok);
__set_bit(SERVICE_ACTION_IN_16, filter->read_ok);
__set_bit(RECEIVE_DIAGNOSTIC, filter->read_ok);
__set_bit(MAINTENANCE_IN, filter->read_ok);
__set_bit(GPCMD_READ_BUFFER_CAPACITY, filter->read_ok);
/* Audio CD commands */
__set_bit(GPCMD_PLAY_CD, filter->read_ok);
__set_bit(GPCMD_PLAY_AUDIO_10, filter->read_ok);
__set_bit(GPCMD_PLAY_AUDIO_MSF, filter->read_ok);
__set_bit(GPCMD_PLAY_AUDIO_TI, filter->read_ok);
__set_bit(GPCMD_PAUSE_RESUME, filter->read_ok);
/* CD/DVD data reading */
__set_bit(GPCMD_READ_CD, filter->read_ok);
__set_bit(GPCMD_READ_CD_MSF, filter->read_ok);
__set_bit(GPCMD_READ_DISC_INFO, filter->read_ok);
__set_bit(GPCMD_READ_CDVD_CAPACITY, filter->read_ok);
__set_bit(GPCMD_READ_DVD_STRUCTURE, filter->read_ok);
__set_bit(GPCMD_READ_HEADER, filter->read_ok);
__set_bit(GPCMD_READ_TRACK_RZONE_INFO, filter->read_ok);
__set_bit(GPCMD_READ_SUBCHANNEL, filter->read_ok);
__set_bit(GPCMD_READ_TOC_PMA_ATIP, filter->read_ok);
__set_bit(GPCMD_REPORT_KEY, filter->read_ok);
__set_bit(GPCMD_SCAN, filter->read_ok);
__set_bit(GPCMD_GET_CONFIGURATION, filter->read_ok);
__set_bit(GPCMD_READ_FORMAT_CAPACITIES, filter->read_ok);
__set_bit(GPCMD_GET_EVENT_STATUS_NOTIFICATION, filter->read_ok);
__set_bit(GPCMD_GET_PERFORMANCE, filter->read_ok);
__set_bit(GPCMD_SEEK, filter->read_ok);
__set_bit(GPCMD_STOP_PLAY_SCAN, filter->read_ok);
/* Basic writing commands */
__set_bit(WRITE_6, filter->write_ok);
__set_bit(WRITE_10, filter->write_ok);
__set_bit(WRITE_VERIFY, filter->write_ok);
__set_bit(WRITE_12, filter->write_ok);
__set_bit(WRITE_VERIFY_12, filter->write_ok);
__set_bit(WRITE_16, filter->write_ok);
__set_bit(WRITE_LONG, filter->write_ok);
__set_bit(WRITE_LONG_2, filter->write_ok);
__set_bit(WRITE_SAME, filter->write_ok);
__set_bit(WRITE_SAME_16, filter->write_ok);
__set_bit(WRITE_SAME_32, filter->write_ok);
__set_bit(ERASE, filter->write_ok);
__set_bit(GPCMD_MODE_SELECT_10, filter->write_ok);
__set_bit(MODE_SELECT, filter->write_ok);
__set_bit(LOG_SELECT, filter->write_ok);
__set_bit(GPCMD_BLANK, filter->write_ok);
__set_bit(GPCMD_CLOSE_TRACK, filter->write_ok);
__set_bit(GPCMD_FLUSH_CACHE, filter->write_ok);
__set_bit(GPCMD_FORMAT_UNIT, filter->write_ok);
__set_bit(GPCMD_REPAIR_RZONE_TRACK, filter->write_ok);
__set_bit(GPCMD_RESERVE_RZONE_TRACK, filter->write_ok);
__set_bit(GPCMD_SEND_DVD_STRUCTURE, filter->write_ok);
__set_bit(GPCMD_SEND_EVENT, filter->write_ok);
__set_bit(GPCMD_SEND_KEY, filter->write_ok);
__set_bit(GPCMD_SEND_OPC, filter->write_ok);
__set_bit(GPCMD_SEND_CUE_SHEET, filter->write_ok);
__set_bit(GPCMD_SET_SPEED, filter->write_ok);
__set_bit(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL, filter->write_ok);
__set_bit(GPCMD_LOAD_UNLOAD, filter->write_ok);
__set_bit(GPCMD_SET_STREAMING, filter->write_ok);
__set_bit(GPCMD_SET_READ_AHEAD, filter->write_ok);
}
int blk_verify_command(unsigned char *cmd, fmode_t mode)
{
struct blk_cmd_filter *filter = &blk_default_cmd_filter;
/* root can do any command. */
if (capable(CAP_SYS_RAWIO))
return 0;
/* Anybody who can open the device can do a read-safe command */
if (test_bit(cmd[0], filter->read_ok))
return 0;
/* Write-safe commands require a writable open */
if (test_bit(cmd[0], filter->write_ok) && (mode & FMODE_WRITE))
return 0;
return -EPERM;
}
EXPORT_SYMBOL(blk_verify_command);
static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq,
struct sg_io_hdr *hdr, fmode_t mode)
{
struct scsi_request *req = scsi_req(rq);
if (copy_from_user(req->cmd, hdr->cmdp, hdr->cmd_len))
return -EFAULT;
if (blk_verify_command(req->cmd, mode))
return -EPERM;
/*
* fill in request structure
*/
req->cmd_len = hdr->cmd_len;
rq->timeout = msecs_to_jiffies(hdr->timeout);
if (!rq->timeout)
rq->timeout = q->sg_timeout;
if (!rq->timeout)
rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
if (rq->timeout < BLK_MIN_SG_TIMEOUT)
rq->timeout = BLK_MIN_SG_TIMEOUT;
return 0;
}
static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
struct bio *bio)
{
struct scsi_request *req = scsi_req(rq);
int r, ret = 0;
/*
* fill in all the output members
*/
hdr->status = req->result & 0xff;
hdr->masked_status = status_byte(req->result);
hdr->msg_status = msg_byte(req->result);
hdr->host_status = host_byte(req->result);
hdr->driver_status = driver_byte(req->result);
hdr->info = 0;
if (hdr->masked_status || hdr->host_status || hdr->driver_status)
hdr->info |= SG_INFO_CHECK;
hdr->resid = req->resid_len;
hdr->sb_len_wr = 0;
if (req->sense_len && hdr->sbp) {
int len = min((unsigned int) hdr->mx_sb_len, req->sense_len);
if (!copy_to_user(hdr->sbp, req->sense, len))
hdr->sb_len_wr = len;
else
ret = -EFAULT;
}
r = blk_rq_unmap_user(bio);
if (!ret)
ret = r;
return ret;
}
static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
struct sg_io_hdr *hdr, fmode_t mode)
{
unsigned long start_time;
ssize_t ret = 0;
int writing = 0;
int at_head = 0;
struct request *rq;
struct scsi_request *req;
struct bio *bio;
if (hdr->interface_id != 'S')
return -EINVAL;
if (hdr->dxfer_len > (queue_max_hw_sectors(q) << 9))
return -EIO;
if (hdr->dxfer_len)
switch (hdr->dxfer_direction) {
default:
return -EINVAL;
case SG_DXFER_TO_DEV:
writing = 1;
break;
case SG_DXFER_TO_FROM_DEV:
case SG_DXFER_FROM_DEV:
break;
}
if (hdr->flags & SG_FLAG_Q_AT_HEAD)
at_head = 1;
ret = -ENOMEM;
rq = blk_get_request(q, writing ? REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
if (IS_ERR(rq))
return PTR_ERR(rq);
req = scsi_req(rq);
if (hdr->cmd_len > BLK_MAX_CDB) {
req->cmd = kzalloc(hdr->cmd_len, GFP_KERNEL);
if (!req->cmd)
goto out_put_request;
}
ret = blk_fill_sghdr_rq(q, rq, hdr, mode);
if (ret < 0)
goto out_free_cdb;
ret = 0;
if (hdr->iovec_count) {
struct iov_iter i;
struct iovec *iov = NULL;
ret = import_iovec(rq_data_dir(rq),
hdr->dxferp, hdr->iovec_count,
0, &iov, &i);
if (ret < 0)
goto out_free_cdb;
/* SG_IO howto says that the shorter of the two wins */
iov_iter_truncate(&i, hdr->dxfer_len);
ret = blk_rq_map_user_iov(q, rq, NULL, &i, GFP_KERNEL);
kfree(iov);
} else if (hdr->dxfer_len)
ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
GFP_KERNEL);
if (ret)
goto out_free_cdb;
bio = rq->bio;
req->retries = 0;
start_time = jiffies;
/* ignore return value. All information is passed back to caller
* (if he doesn't check that is his problem).
* N.B. a non-zero SCSI status is _not_ necessarily an error.
*/
blk_execute_rq(q, bd_disk, rq, at_head);
hdr->duration = jiffies_to_msecs(jiffies - start_time);
ret = blk_complete_sghdr_rq(rq, hdr, bio);
out_free_cdb:
scsi_req_free_cmd(req);
out_put_request:
blk_put_request(rq);
return ret;
}
/**
* sg_scsi_ioctl -- handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
* @q: request queue to send scsi commands down
* @disk: gendisk to operate on (option)
* @mode: mode used to open the file through which the ioctl has been
* submitted
* @sic: userspace structure describing the command to perform
*
* Send down the scsi command described by @sic to the device below
* the request queue @q. If @file is non-NULL it's used to perform
* fine-grained permission checks that allow users to send down
* non-destructive SCSI commands. If the caller has a struct gendisk
* available it should be passed in as @disk to allow the low level
* driver to use the information contained in it. A non-NULL @disk
* is only allowed if the caller knows that the low level driver doesn't
* need it (e.g. in the scsi subsystem).
*
* Notes:
* - This interface is deprecated - users should use the SG_IO
* interface instead, as this is a more flexible approach to
* performing SCSI commands on a device.
* - The SCSI command length is determined by examining the 1st byte
* of the given command. There is no way to override this.
* - Data transfers are limited to PAGE_SIZE
* - The length (x + y) must be at least OMAX_SB_LEN bytes long to
* accommodate the sense buffer when an error occurs.
* The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
* old code will not be surprised.
* - If a Unix error occurs (e.g. ENOMEM) then the user will receive
* a negative return and the Unix error code in 'errno'.
* If the SCSI command succeeds then 0 is returned.
* Positive numbers returned are the compacted SCSI error codes (4
* bytes in one int) where the lowest byte is the SCSI status.
*/
int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
struct scsi_ioctl_command __user *sic)
{
enum { OMAX_SB_LEN = 16 }; /* For backward compatibility */
struct request *rq;
struct scsi_request *req;
int err;
unsigned int in_len, out_len, bytes, opcode, cmdlen;
char *buffer = NULL;
if (!sic)
return -EINVAL;
/*
* get in an out lengths, verify they don't exceed a page worth of data
*/
if (get_user(in_len, &sic->inlen))
return -EFAULT;
if (get_user(out_len, &sic->outlen))
return -EFAULT;
if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
return -EINVAL;
if (get_user(opcode, sic->data))
return -EFAULT;
bytes = max(in_len, out_len);
if (bytes) {
buffer = kzalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
if (!buffer)
return -ENOMEM;
}
rq = blk_get_request(q, in_len ? REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
if (IS_ERR(rq)) {
err = PTR_ERR(rq);
goto error_free_buffer;
}
req = scsi_req(rq);
cmdlen = COMMAND_SIZE(opcode);
/*
* get command and data to send to device, if any
*/
err = -EFAULT;
req->cmd_len = cmdlen;
if (copy_from_user(req->cmd, sic->data, cmdlen))
goto error;
if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
goto error;
err = blk_verify_command(req->cmd, mode);
if (err)
goto error;
/* default. possible overriden later */
req->retries = 5;
switch (opcode) {
case SEND_DIAGNOSTIC:
case FORMAT_UNIT:
rq->timeout = FORMAT_UNIT_TIMEOUT;
req->retries = 1;
break;
case START_STOP:
rq->timeout = START_STOP_TIMEOUT;
break;
case MOVE_MEDIUM:
rq->timeout = MOVE_MEDIUM_TIMEOUT;
break;
case READ_ELEMENT_STATUS:
rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
break;
case READ_DEFECT_DATA:
rq->timeout = READ_DEFECT_DATA_TIMEOUT;
req->retries = 1;
break;
default:
rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
break;
}
if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, GFP_NOIO)) {
err = DRIVER_ERROR << 24;
goto error;
}
blk_execute_rq(q, disk, rq, 0);
err = req->result & 0xff; /* only 8 bit SCSI status */
if (err) {
if (req->sense_len && req->sense) {
bytes = (OMAX_SB_LEN > req->sense_len) ?
req->sense_len : OMAX_SB_LEN;
if (copy_to_user(sic->data, req->sense, bytes))
err = -EFAULT;
}
} else {
if (copy_to_user(sic->data, buffer, out_len))
err = -EFAULT;
}
error:
blk_put_request(rq);
error_free_buffer:
kfree(buffer);
return err;
}
EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
/* Send basic block requests */
static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
int cmd, int data)
{
struct request *rq;
int err;
rq = blk_get_request(q, REQ_OP_SCSI_OUT, 0);
if (IS_ERR(rq))
return PTR_ERR(rq);
rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
scsi_req(rq)->cmd[0] = cmd;
scsi_req(rq)->cmd[4] = data;
scsi_req(rq)->cmd_len = 6;
blk_execute_rq(q, bd_disk, rq, 0);
err = scsi_req(rq)->result ? -EIO : 0;
blk_put_request(rq);
return err;
}
static inline int blk_send_start_stop(struct request_queue *q,
struct gendisk *bd_disk, int data)
{
return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
}
int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mode,
unsigned int cmd, void __user *arg)
{
int err;
if (!q)
return -ENXIO;
switch (cmd) {
/*
* new sgv3 interface
*/
case SG_GET_VERSION_NUM:
err = sg_get_version(arg);
break;
case SCSI_IOCTL_GET_IDLUN:
err = scsi_get_idlun(q, arg);
break;
case SCSI_IOCTL_GET_BUS_NUMBER:
err = scsi_get_bus(q, arg);
break;
case SG_SET_TIMEOUT:
err = sg_set_timeout(q, arg);
break;
case SG_GET_TIMEOUT:
err = sg_get_timeout(q);
break;
case SG_GET_RESERVED_SIZE:
err = sg_get_reserved_size(q, arg);
break;
case SG_SET_RESERVED_SIZE:
err = sg_set_reserved_size(q, arg);
break;
case SG_EMULATED_HOST:
err = sg_emulated_host(q, arg);
break;
case SG_IO: {
struct sg_io_hdr hdr;
err = -EFAULT;
if (copy_from_user(&hdr, arg, sizeof(hdr)))
break;
err = sg_io(q, bd_disk, &hdr, mode);
if (err == -EFAULT)
break;
if (copy_to_user(arg, &hdr, sizeof(hdr)))
err = -EFAULT;
break;
}
case CDROM_SEND_PACKET: {
struct cdrom_generic_command cgc;
struct sg_io_hdr hdr;
err = -EFAULT;
if (copy_from_user(&cgc, arg, sizeof(cgc)))
break;
cgc.timeout = clock_t_to_jiffies(cgc.timeout);
memset(&hdr, 0, sizeof(hdr));
hdr.interface_id = 'S';
hdr.cmd_len = sizeof(cgc.cmd);
hdr.dxfer_len = cgc.buflen;
err = 0;
switch (cgc.data_direction) {
case CGC_DATA_UNKNOWN:
hdr.dxfer_direction = SG_DXFER_UNKNOWN;
break;
case CGC_DATA_WRITE:
hdr.dxfer_direction = SG_DXFER_TO_DEV;
break;
case CGC_DATA_READ:
hdr.dxfer_direction = SG_DXFER_FROM_DEV;
break;
case CGC_DATA_NONE:
hdr.dxfer_direction = SG_DXFER_NONE;
break;
default:
err = -EINVAL;
}
if (err)
break;
hdr.dxferp = cgc.buffer;
hdr.sbp = cgc.sense;
if (hdr.sbp)
hdr.mx_sb_len = sizeof(struct request_sense);
hdr.timeout = jiffies_to_msecs(cgc.timeout);
hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
hdr.cmd_len = sizeof(cgc.cmd);
err = sg_io(q, bd_disk, &hdr, mode);
if (err == -EFAULT)
break;
if (hdr.status)
err = -EIO;
cgc.stat = err;
cgc.buflen = hdr.resid;
if (copy_to_user(arg, &cgc, sizeof(cgc)))
err = -EFAULT;
break;
}
/*
* old junk scsi send command ioctl
*/
case SCSI_IOCTL_SEND_COMMAND:
printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
err = -EINVAL;
if (!arg)
break;
err = sg_scsi_ioctl(q, bd_disk, mode, arg);
break;
case CDROMCLOSETRAY:
err = blk_send_start_stop(q, bd_disk, 0x03);
break;
case CDROMEJECT:
err = blk_send_start_stop(q, bd_disk, 0x02);
break;
default:
err = -ENOTTY;
}
return err;
}
EXPORT_SYMBOL(scsi_cmd_ioctl);
int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
{
if (bd && bd == bd->bd_contains)
return 0;
if (capable(CAP_SYS_RAWIO))
return 0;
return -ENOIOCTLCMD;
}
EXPORT_SYMBOL(scsi_verify_blk_ioctl);
int scsi_cmd_blk_ioctl(struct block_device *bd, fmode_t mode,
unsigned int cmd, void __user *arg)
{
int ret;
ret = scsi_verify_blk_ioctl(bd, cmd);
if (ret < 0)
return ret;
return scsi_cmd_ioctl(bd->bd_disk->queue, bd->bd_disk, mode, cmd, arg);
}
EXPORT_SYMBOL(scsi_cmd_blk_ioctl);
/**
* scsi_req_init - initialize certain fields of a scsi_request structure
* @req: Pointer to a scsi_request structure.
* Initializes .__cmd[], .cmd, .cmd_len and .sense_len but no other members
* of struct scsi_request.
*/
void scsi_req_init(struct scsi_request *req)
{
memset(req->__cmd, 0, sizeof(req->__cmd));
req->cmd = req->__cmd;
req->cmd_len = BLK_MAX_CDB;
req->sense_len = 0;
}
EXPORT_SYMBOL(scsi_req_init);
static int __init blk_scsi_ioctl_init(void)
{
blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
return 0;
}
fs_initcall(blk_scsi_ioctl_init);
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