diff options
Diffstat (limited to 'drivers/s390/block/dcssblk.c')
| -rw-r--r-- | drivers/s390/block/dcssblk.c | 44 |
1 files changed, 40 insertions, 4 deletions
diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c index 16ab8d363ac..6bc27d52326 100644 --- a/drivers/s390/block/dcssblk.c +++ b/drivers/s390/block/dcssblk.c @@ -35,14 +35,17 @@ static int dcssblk_open(struct inode *inode, struct file *filp); static int dcssblk_release(struct inode *inode, struct file *filp); static int dcssblk_make_request(struct request_queue *q, struct bio *bio); +static int dcssblk_direct_access(struct block_device *bdev, sector_t secnum, + unsigned long *data); static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0"; static int dcssblk_major; static struct block_device_operations dcssblk_devops = { - .owner = THIS_MODULE, - .open = dcssblk_open, - .release = dcssblk_release, + .owner = THIS_MODULE, + .open = dcssblk_open, + .release = dcssblk_release, + .direct_access = dcssblk_direct_access, }; static ssize_t dcssblk_add_store(struct device * dev, struct device_attribute *attr, const char * buf, @@ -641,6 +644,20 @@ dcssblk_make_request(request_queue_t *q, struct bio *bio) /* Request beyond end of DCSS segment. */ goto fail; } + /* verify data transfer direction */ + if (dev_info->is_shared) { + switch (dev_info->segment_type) { + case SEG_TYPE_SR: + case SEG_TYPE_ER: + case SEG_TYPE_SC: + /* cannot write to these segments */ + if (bio_data_dir(bio) == WRITE) { + PRINT_WARN("rejecting write to ro segment %s\n", dev_info->dev.bus_id); + goto fail; + } + } + } + index = (bio->bi_sector >> 3); bio_for_each_segment(bvec, bio, i) { page_addr = (unsigned long) @@ -661,7 +678,26 @@ dcssblk_make_request(request_queue_t *q, struct bio *bio) bio_endio(bio, bytes_done, 0); return 0; fail: - bio_io_error(bio, bytes_done); + bio_io_error(bio, bio->bi_size); + return 0; +} + +static int +dcssblk_direct_access (struct block_device *bdev, sector_t secnum, + unsigned long *data) +{ + struct dcssblk_dev_info *dev_info; + unsigned long pgoff; + + dev_info = bdev->bd_disk->private_data; + if (!dev_info) + return -ENODEV; + if (secnum % (PAGE_SIZE/512)) + return -EINVAL; + pgoff = secnum / (PAGE_SIZE / 512); + if ((pgoff+1)*PAGE_SIZE-1 > dev_info->end - dev_info->start) + return -ERANGE; + *data = (unsigned long) (dev_info->start+pgoff*PAGE_SIZE); return 0; } |