Messages in this thread | | | Date | Thu, 25 Nov 1999 16:16:03 -0800 (PST) | From | Linus Torvalds <> | Subject | Re: Request for comments (kdev_t and friends...) |
| |
On Fri, 26 Nov 1999, Martin Dalecki wrote: > > The attached patch is basically showing the full impact of any attempt to > enhance the kdev_t struct handling inside the current linux kernel.
I'm pretty convinced that "kdev_t" is just broken.
What we should have is to just make
open_special_device() .. close_special_device();
and hide a real pointer to a "struct block_device *" (or "struct char_device *" as it may be) in the file pointer.
That "struct block_device *" would not have any resemblance to "dev_t" at all, and wouldn't have any of these MAJOR/MINOR issues. It would just contain the full data - size of the device, offset of the device into a "larger" device, pointers to the requests queues etc etc.
So then the lookup would only ever be done once, at file open time. The actual read/write functions (and bread() etc) would use the full block device pointer and wouldn't need to search for anything at all..
Linus
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
| |