Alan Stern <[EMAIL PROTECTED]> wrote:
> Well, if Doug wants to reduce the value returned by SG_GET_RESERVED_SIZE,
> it's okay with me. An advantage of doing this is that older versions of
> cdrecord would then work correctly.
>
> However you don't seem to realize that people can use programs like
> cdrecord with devices whose drivers don't support SG_GET_RESERVED_SIZE --
> because that ioctl works only with sg. Programs would have to try
> SG_GET_RESERVED_SIZE and if it faied, then try BLKSECTGET.
Is there any reason not to have one single ioctl for one basic feature?
> Remember also, the "reserved size" is _not_ the maximum allowed size of a
> DMA transfer. Rather, it is the size of an internal buffer maintained by
> sg. It's legal to do an I/O transfer larger than the "reserved size", but
> it is not legal to do an I/O transfer larger than max_sectors.
At the time the call SG_GET_RESERVED_SIZE has been discussed/defined, we did
originally agree that the max value should be limited to what the HW allows
as DMA size. This is why I did originally files a bug against
SG_GET_RESERVED_SIZE.
Jörg
--
EMail:[EMAIL PROTECTED] (home) Jörg Schilling D-13353 Berlin
[EMAIL PROTECTED] (uni)
[EMAIL PROTECTED] (work) Blog: http://schily.blogspot.com/
URL: http://cdrecord.berlios.de/old/private/ ftp://ftp.berlios.de/pub/schily
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
