diff options
| -rw-r--r-- | mkfs_msdos.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/mkfs_msdos.c b/mkfs_msdos.c index 0ef30f2..878ff8f 100644 --- a/mkfs_msdos.c +++ b/mkfs_msdos.c @@ -847,16 +847,17 @@ static int getdiskinfo(int fd, const char *fname, const char *dtype, if (ckgeom(fname, bpb->bpbBytesPerSec, "bytes/sector") == -1) return -1; - u_long block_size; - if (ioctl(fd, BLKGETSIZE, &block_size)) { - err(1, "ioctl(BLKGETSIZE) failed"); + u_long device_size; + if (ioctl(fd, BLKGETSIZE64, &device_size)) { + err(1, "ioctl(BLKGETSIZE64) failed"); } - if (block_size > UINT32_MAX) { - errx(1, "block size too large: %lu", block_size); + u_long sectors = device_size/bpb->bpbBytesPerSec; + if (sectors > UINT32_MAX) { + errx(1, "too many sectors: %lu (%lu byte device, %u bytes/sector)", + sectors, device_size, bpb->bpbBytesPerSec); } - - bpb->bpbHugeSectors = (u_int)block_size; + bpb->bpbHugeSectors = sectors; bpb->bpbSecPerTrack = 63; if (ckgeom(fname, bpb->bpbSecPerTrack, "sectors/track") == -1) return -1; |