block: move cmdfilter from gendisk to request_queue

cmd_filter works only for the block layer SG_IO with SCSI block
devices. It breaks scsi/sg.c, bsg, and the block layer SG_IO with SCSI
character devices (such as st). We hit a kernel crash with them.

The problem is that cmd_filter code accesses to gendisk (having struct
blk_scsi_cmd_filter) via inode->i_bdev->bd_disk. It works for only
SCSI block device files. With character device files, inode->i_bdev
leads you to struct cdev. inode->i_bdev->bd_disk->blk_scsi_cmd_filter
isn't safe.

SCSI ULDs don't expose gendisk; they keep it private. bsg needs to be
independent on any protocols. We shouldn't change ULDs to expose their
gendisk.

This patch moves struct blk_scsi_cmd_filter from gendisk to
request_queue, a common object, which eveyone can access to.

The user interface doesn't change; users can change the filters via
/sys/block/. gendisk has a pointer to request_queue so the cmd_filter
code accesses to struct blk_scsi_cmd_filter.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 6 insertions, 112 deletions

diff --git a/block/cmd-filter.c b/block/cmd-filter.c
index eec4404fd357..c705c33361a0 100644
--- a/block/cmd-filter.c
+++ b/block/cmd-filter.c
@@ -27,8 +27,8 @@
 #include <scsi/scsi.h>
 #include <linux/cdrom.h>
 
-int blk_cmd_filter_verify_command(struct blk_scsi_cmd_filter *filter,
-				  unsigned char *cmd, mode_t *f_mode)
+int blk_verify_command(struct blk_scsi_cmd_filter *filter,
+		       unsigned char *cmd, int has_write_perm)
 {
 	/* root can do any command. */
 	if (capable(CAP_SYS_RAWIO))
@@ -43,30 +43,11 @@ int blk_cmd_filter_verify_command(struct blk_scsi_cmd_filter *filter,
 		return 0;
 
 	/* Write-safe commands require a writable open */
-	if (test_bit(cmd[0], filter->write_ok) && (*f_mode & FMODE_WRITE))
+	if (test_bit(cmd[0], filter->write_ok) && has_write_perm)
 		return 0;
 
 	return -EPERM;
 }
-EXPORT_SYMBOL(blk_cmd_filter_verify_command);
-
-int blk_verify_command(struct file *file, unsigned char *cmd)
-{
-	struct gendisk *disk;
-	struct inode *inode;
-
-	if (!file)
-		return -EINVAL;
-
-	inode = file->f_dentry->d_inode;
-	if (!inode)
-		return -EINVAL;
-
-	disk = inode->i_bdev->bd_disk;
-
-	return blk_cmd_filter_verify_command(&disk->cmd_filter,
-						 cmd, &file->f_mode);
-}
 EXPORT_SYMBOL(blk_verify_command);
 
 /* and now, the sysfs stuff */
@@ -219,114 +200,27 @@ static struct kobj_type rcf_ktype = {
 	.default_attrs = default_attrs,
 };
 
-#ifndef MAINTENANCE_IN_CMD
-#define MAINTENANCE_IN_CMD 0xa3
-#endif
-
-static void rcf_set_defaults(struct blk_scsi_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, filter->read_ok);
-	__set_bit(RECEIVE_DIAGNOSTIC, filter->read_ok);
-	__set_bit(MAINTENANCE_IN_CMD, 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(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);
-}
-
 int blk_register_filter(struct gendisk *disk)
 {
 	int ret;
-	struct blk_scsi_cmd_filter *filter = &disk->cmd_filter;
+	struct blk_scsi_cmd_filter *filter = &disk->queue->cmd_filter;
 	struct kobject *parent = kobject_get(disk->holder_dir->parent);
 
 	if (!parent)
 		return -ENODEV;
 
 	ret = kobject_init_and_add(&filter->kobj, &rcf_ktype, parent,
-				 "%s", "cmd_filter");
+				   "%s", "cmd_filter");
 
 	if (ret < 0)
 		return ret;
 
-	rcf_set_defaults(filter);
 	return 0;
 }
 
 void blk_unregister_filter(struct gendisk *disk)
 {
-	struct blk_scsi_cmd_filter *filter = &disk->cmd_filter;
+	struct blk_scsi_cmd_filter *filter = &disk->queue->cmd_filter;
 
 	kobject_put(&filter->kobj);
 	kobject_put(disk->holder_dir->parent);