I am writing a kernel module that lists block devices and their corresponding dev_t which I will use for tracing.
The following is the structure block_device
struct block_device {
dev_t bd_dev; /* not a kdev_t - it's a search key */
int bd_openers;
struct inode * bd_inode; /* will die */
struct super_block * bd_super;
struct mutex bd_mutex; /* open/close mutex */
struct list_head bd_inodes;
void * bd_claiming;
void * bd_holder;
int bd_holders;
bool bd_write_holder;
#ifdef CONFIG_SYSFS
struct list_head bd_holder_disks;
#endif
struct block_device * bd_contains;
unsigned bd_block_size;
struct hd_struct * bd_part;
/* number of times partitions within this device have been opened. */
unsigned bd_part_count;
int bd_invalidated;
struct gendisk * bd_disk;
struct request_queue * bd_queue;
struct list_head bd_list;
............
};
bd_list is a linked list containing all block devices in the system. all_bdevs ( fs/block_dev.c ) is the head of the list but the problem that it's not exported. Is there a way to iterate block devices inside a kernel module ?
