From abf5439370491dd6fbb4fe1a7939680d2a9bc9d4 Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Sat, 16 Aug 2008 14:10:05 +0900 Subject: 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 Signed-off-by: Jens Axboe --- block/bsg.c | 44 +++++++++++--------------------------------- 1 file changed, 11 insertions(+), 33 deletions(-) (limited to 'block/bsg.c') diff --git a/block/bsg.c b/block/bsg.c index 5a68b09a69b..0aae8d7ba99 100644 --- a/block/bsg.c +++ b/block/bsg.c @@ -45,8 +45,6 @@ struct bsg_device { char name[BUS_ID_SIZE]; int max_queue; unsigned long flags; - struct blk_scsi_cmd_filter *cmd_filter; - mode_t *f_mode; }; enum { @@ -174,7 +172,8 @@ unlock: } static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq, - struct sg_io_v4 *hdr, struct bsg_device *bd) + struct sg_io_v4 *hdr, struct bsg_device *bd, + int has_write_perm) { if (hdr->request_len > BLK_MAX_CDB) { rq->cmd = kzalloc(hdr->request_len, GFP_KERNEL); @@ -187,8 +186,7 @@ static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq, return -EFAULT; if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) { - if (blk_cmd_filter_verify_command(bd->cmd_filter, rq->cmd, - bd->f_mode)) + if (blk_verify_command(&q->cmd_filter, rq->cmd, has_write_perm)) return -EPERM; } else if (!capable(CAP_SYS_RAWIO)) return -EPERM; @@ -244,7 +242,7 @@ bsg_validate_sgv4_hdr(struct request_queue *q, struct sg_io_v4 *hdr, int *rw) * map sg_io_v4 to a request. */ static struct request * -bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr) +bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, int has_write_perm) { struct request_queue *q = bd->queue; struct request *rq, *next_rq = NULL; @@ -266,7 +264,7 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr) rq = blk_get_request(q, rw, GFP_KERNEL); if (!rq) return ERR_PTR(-ENOMEM); - ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd); + ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd, has_write_perm); if (ret) goto out; @@ -568,25 +566,6 @@ static inline void bsg_set_block(struct bsg_device *bd, struct file *file) set_bit(BSG_F_BLOCK, &bd->flags); } -static void bsg_set_cmd_filter(struct bsg_device *bd, - struct file *file) -{ - struct inode *inode; - struct gendisk *disk; - - if (!file) - return; - - inode = file->f_dentry->d_inode; - if (!inode) - return; - - disk = inode->i_bdev->bd_disk; - - bd->cmd_filter = &disk->cmd_filter; - bd->f_mode = &file->f_mode; -} - /* * Check if the error is a "real" error that we should return. */ @@ -608,7 +587,6 @@ bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) dprintk("%s: read %Zd bytes\n", bd->name, count); bsg_set_block(bd, file); - bsg_set_cmd_filter(bd, file); bytes_read = 0; ret = __bsg_read(buf, count, bd, NULL, &bytes_read); @@ -621,7 +599,7 @@ bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) } static int __bsg_write(struct bsg_device *bd, const char __user *buf, - size_t count, ssize_t *bytes_written) + size_t count, ssize_t *bytes_written, int has_write_perm) { struct bsg_command *bc; struct request *rq; @@ -652,7 +630,7 @@ static int __bsg_write(struct bsg_device *bd, const char __user *buf, /* * get a request, fill in the blanks, and add to request queue */ - rq = bsg_map_hdr(bd, &bc->hdr); + rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm); if (IS_ERR(rq)) { ret = PTR_ERR(rq); rq = NULL; @@ -683,10 +661,11 @@ bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) dprintk("%s: write %Zd bytes\n", bd->name, count); bsg_set_block(bd, file); - bsg_set_cmd_filter(bd, file); bytes_written = 0; - ret = __bsg_write(bd, buf, count, &bytes_written); + ret = __bsg_write(bd, buf, count, &bytes_written, + file->f_mode & FMODE_WRITE); + *ppos = bytes_written; /* @@ -792,7 +771,6 @@ static struct bsg_device *bsg_add_device(struct inode *inode, bd->queue = rq; bsg_set_block(bd, file); - bsg_set_cmd_filter(bd, file); atomic_set(&bd->ref_count, 1); mutex_lock(&bsg_mutex); @@ -943,7 +921,7 @@ static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg) if (copy_from_user(&hdr, uarg, sizeof(hdr))) return -EFAULT; - rq = bsg_map_hdr(bd, &hdr); + rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE); if (IS_ERR(rq)) return PTR_ERR(rq); -- cgit v1.2.3