On Wed, Mar 07 2001, Jens Axboe wrote:
> On Wed, Mar 07 2001, Jens Axboe wrote:
> > Really good question, I sent this patch in the private thread between
> > me and Pozsar just in case the length is what the drive complains about.
>
> Agrh, that's not all. I will fix this properly, sorry about the noise.
This should work. Pozsar, could you test?
I suspect that Derik is right though, that the 05/24/00 is because
the dvdinfo is requesting info for a non-existant physical layer.
I've attempted to quiet that error. You dvdinfo output did look
very odd.
--
Jens Axboe
--- /opt/kernel/linux-2.4.3-pre3/drivers/cdrom/cdrom.c Thu Feb 22 14:55:22 2001
+++ drivers/cdrom/cdrom.c Wed Mar 7 23:25:52 2001
@@ -1171,42 +1171,50 @@
static int dvd_read_physical(struct cdrom_device_info *cdi, dvd_struct *s)
{
- int ret, i;
- u_char buf[4 + 4 * 20], *base;
+ unsigned char buf[20], *base;
struct dvd_layer *layer;
struct cdrom_generic_command cgc;
struct cdrom_device_ops *cdo = cdi->ops;
+ int ret, layer_num = s->physical.layer_num;
+
+ if (layer_num >= DVD_LAYERS)
+ return -EINVAL;
init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE;
- cgc.cmd[6] = s->physical.layer_num;
+ cgc.cmd[6] = layer_num;
cgc.cmd[7] = s->type;
cgc.cmd[9] = cgc.buflen & 0xff;
+ /*
+ * refrain from reporting errors on non-existing layers (mainly)
+ */
+ cgc.quiet = 1;
+
if ((ret = cdo->generic_packet(cdi, &cgc)))
return ret;
base = &buf[4];
- layer = &s->physical.layer[0];
+ layer = &s->physical.layer[layer_num];
- /* place the data... really ugly, but at least we won't have to
- worry about endianess in userspace or here. */
- for (i = 0; i < 4; ++i, base += 20, ++layer) {
- memset(layer, 0, sizeof(*layer));
- layer->book_version = base[0] & 0xf;
- layer->book_type = base[0] >> 4;
- layer->min_rate = base[1] & 0xf;
- layer->disc_size = base[1] >> 4;
- layer->layer_type = base[2] & 0xf;
- layer->track_path = (base[2] >> 4) & 1;
- layer->nlayers = (base[2] >> 5) & 3;
- layer->track_density = base[3] & 0xf;
- layer->linear_density = base[3] >> 4;
- layer->start_sector = base[5] << 16 | base[6] << 8 | base[7];
- layer->end_sector = base[9] << 16 | base[10] << 8 | base[11];
- layer->end_sector_l0 = base[13] << 16 | base[14] << 8 | base[15];
- layer->bca = base[16] >> 7;
- }
+ /*
+ * place the data... really ugly, but at least we won't have to
+ * worry about endianess in userspace.
+ */
+ memset(layer, 0, sizeof(*layer));
+ layer->book_version = base[0] & 0xf;
+ layer->book_type = base[0] >> 4;
+ layer->min_rate = base[1] & 0xf;
+ layer->disc_size = base[1] >> 4;
+ layer->layer_type = base[2] & 0xf;
+ layer->track_path = (base[2] >> 4) & 1;
+ layer->nlayers = (base[2] >> 5) & 3;
+ layer->track_density = base[3] & 0xf;
+ layer->linear_density = base[3] >> 4;
+ layer->start_sector = base[5] << 16 | base[6] << 8 | base[7];
+ layer->end_sector = base[9] << 16 | base[10] << 8 | base[11];
+ layer->end_sector_l0 = base[13] << 16 | base[14] << 8 | base[15];
+ layer->bca = base[16] >> 7;
return 0;
}
--- /opt/kernel/linux-2.4.3-pre3/include/linux/cdrom.h Tue Jan 30 08:24:56 2001
+++ include/linux/cdrom.h Wed Mar 7 23:00:07 2001
@@ -524,10 +524,12 @@
__u32 end_sector_l0;
};
+#define DVD_LAYERS 4
+
struct dvd_physical {
__u8 type;
__u8 layer_num;
- struct dvd_layer layer[4];
+ struct dvd_layer layer[DVD_LAYERS];
};
struct dvd_copyright {
