diff options
| -rw-r--r-- | Makefile | 4 | ||||
| -rw-r--r-- | sbdd.c | 59 |
2 files changed, 62 insertions, 1 deletions
@@ -36,6 +36,8 @@ ######## Makefile TARG_BLK = /dev/disk/by-id/ata-QEMU_HARDDISK_QM00001 +TARG_BLK2 = /dev/disk/by-id/ata-QEMU_HARDDISK_QM00003 +DISK_LIST = "$(TARG_BLK),$(TARG_BLK2)" SBDD_BLK = /dev/sbdd DD_ARGS = bs=512 count=1 @@ -46,7 +48,7 @@ clean: load: dmesg -C - insmod sbdd.ko disk="$(TARG_BLK)" + insmod sbdd.ko disk="$(TARG_BLK)" disklist=$(DISK_LIST) dmesg unload: @@ -22,6 +22,13 @@ #define SBDD_NAME "sbdd" #define SBDD_BDEV_MODE (FMODE_READ | FMODE_WRITE) +#define MAX_RAID_DISK 6 + +struct raiddisk { + sector_t capacity; + unsigned int max_sectors; + struct block_device *bdev; +}; struct sbdd { wait_queue_head_t exitwait; @@ -32,6 +39,7 @@ struct sbdd { struct gendisk *gd; struct request_queue *q; struct block_device *bdev; + struct raiddisk disks[MAX_RAID_DISK]; }; static struct sbdd __sbdd; @@ -39,6 +47,9 @@ static int __sbdd_major = 0; static struct bio_set __sbdd_bio_set; static char *__sbdd_disk = "/dev/disk/by-id/ata-QEMU_HARDDISK_QM00001"; +static char *__sbdd_disklist[MAX_RAID_DISK] = { NULL }; +static unsigned int __sbdd_diskcount; + struct sbdd_io_bio { struct bio *original_bio; }; @@ -139,8 +150,10 @@ static struct block_device_operations const __sbdd_bdev_ops = { static int sbdd_create(void) { int ret = 0; + int disk = 0; unsigned short lblock_size; unsigned int max_sectors; + sector_t totalsize = 0; ret = bioset_init(&__sbdd_bio_set, BIO_POOL_SIZE, 0, 0); if (ret) { @@ -185,6 +198,40 @@ static int sbdd_create(void) return -ENOENT; } + for (disk = 0; disk < __sbdd_diskcount; disk++) { + pr_info("[%d] opening %s", disk, __sbdd_disklist[disk]); + + __sbdd.disks[disk].bdev = blkdev_get_by_path( + __sbdd_disklist[disk], SBDD_BDEV_MODE, THIS_MODULE); + if (!__sbdd.disks[disk].bdev || IS_ERR(__sbdd.disks[disk].bdev)) { + pr_err("blkdev_get_by_path(\"%s\") failed with %ld\n", + __sbdd_disklist[disk], + PTR_ERR(__sbdd.disks[disk].bdev)); + return -ENOENT; + } + + /* Set up device characteristics */ + __sbdd.disks[disk].capacity = get_capacity(__sbdd.disks[disk].bdev->bd_disk); + pr_info("[%d] capacity: %llu\n", disk, __sbdd.disks[disk].capacity); + + /* Get the smallest disk size in the set */ + if (disk == 0) { + totalsize = __sbdd.disks[disk].capacity; + } else { + if (__sbdd.disks[disk].capacity < totalsize) { + totalsize = __sbdd.disks[disk].capacity; + } + } + __sbdd.disks[disk].max_sectors = queue_max_hw_sectors(bdev_get_queue(__sbdd.disks[disk].bdev)); + pr_info("[%d] max_sectors = %d\n", disk, __sbdd.disks[disk].max_sectors); + } + + pr_info("%d disks processed\n", disk); + + disk--; + /* `totalsize` equals the smallest disk size, simply multiple it out to disk count */ + totalsize *= __sbdd_diskcount; + /* Configure queue */ lblock_size = bdev_logical_block_size(__sbdd.bdev); blk_queue_logical_block_size(__sbdd.q, lblock_size); @@ -218,6 +265,8 @@ static int sbdd_create(void) static void sbdd_delete(void) { + int disk; + atomic_set(&__sbdd.deleting, 1); wait_event(__sbdd.exitwait, !atomic_read(&__sbdd.refs_cnt)); @@ -233,6 +282,13 @@ static void sbdd_delete(void) blkdev_put(__sbdd.bdev, SBDD_BDEV_MODE); } + for (disk = 0; disk < __sbdd_diskcount; disk++) { + if (__sbdd.disks[disk].bdev) { + pr_info("release a handle on the %s\n", __sbdd_disklist[disk]); + blkdev_put(__sbdd.disks[disk].bdev, SBDD_BDEV_MODE); + } + } + if (__sbdd.q) { pr_info("cleaning up queue\n"); blk_cleanup_queue(__sbdd.q); @@ -295,6 +351,9 @@ module_exit(sbdd_exit); /* Set desired target disk with insmod */ module_param_named(disk, __sbdd_disk, charp, S_IRUGO); +/* Set desired disk list with insmod */ +module_param_array_named(disklist, __sbdd_disklist, charp, &__sbdd_diskcount, S_IRUGO); + /* Note for the kernel: a free license module. A warning will be outputted without it. */ MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Simple Block Device Driver"); |