On Sat, 26 Jul 2008 18:03:23 +0900 FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx> wrote: > 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@xxxxxxxxxxxxx> > --- > block/bsg.c | 45 +++++------------- > block/cmd-filter.c | 118 ++-------------------------------------------- > block/scsi_ioctl.c | 94 ++++++++++++++++++++++++++++++++++++- > drivers/scsi/scsi_lib.c | 2 + > drivers/scsi/sg.c | 11 ++++- > include/linux/blkdev.h | 16 +++++- > include/linux/genhd.h | 10 ---- > 7 files changed, 133 insertions(+), 163 deletions(-) (snip) > diff --git a/block/bsg.c b/block/bsg.c > diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c > index 88d1b5f..51cdae8 100644 > --- a/drivers/scsi/scsi_lib.c > +++ b/drivers/scsi/scsi_lib.c > @@ -1617,6 +1617,8 @@ struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost, > */ > blk_queue_dma_alignment(q, 0x03); > > + blk_set_cmd_filter_defaults(&q->cmd_filter); > + I guess that I was SCSI biased. Some block drivers (such as cciss) also support some of SCSI commands and use blk_verify_command. They also need to call blk_set_cmd_filter_defaults. I add blk_set_cmd_filter_defaults to blk_init_queue_node (and removed one in __scsi_alloc_queue). Adding it to blk_alloc_queue_node should be fine but blk_init_queue_node looks a reasonable place. I put this patchset with Adel's sysfs interface fix to: git://git.kernel.org/pub/scm/linux/kernel/git/tomo/linux-2.6-misc.git cmdfilter -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
