Back out Axboe-style quasi-S/G and replace it with one command and
repeated URBs. This is similar to what usb-storage does, only instead
of a few URBs allocated together, one URB is reused.
Jens's idea was very nice, but it collapsed when I had to support
packet commads for CD burning. I cannot issue two or more packet
commands where application expected only one.
However, burning does not work completely yet. The cdrecord starts,
recognizes the device, then aborts without writing a TOC.
Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When Al Viro saw the ub.c, he observed that it was a proof positive of
Linus not reading patches anymore: names like fo_ob_ar_ba_2 used to
cause serious fireworks. In my defence, any good scheme can be pushed
to the realm of absurd if pushed far enough.
Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Evidently, Yani Ioannou's display is wider than mine.
Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This the quasi-S/G patch for ub as suggested by Jens Axboe at OLS and
implemented that night before 4 a.m. Surprisingly, it worked right away...
Alas, I had to skip some OLS partying, but it was for the good cause.
Now the speed of ub is quite acceptable even on partitions with small
block size.
The ub does not really support S/G. Instead, it just tells the block
layer that it does. Then, most of the time, the block layer merges
requests and passes single-segmnent requests down to ub; everything
works as before. Very rarely ub gets an unmerged S/G request. In such
case, it issues several commands to the device.
I added a small array of counters to monitor the merging (sg_stat).
This may be dropped later.
Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch fixes a microcode lockup in my CD-ROM adapters when a blank CD
is inserted. However, do not try to burn CDs yet! I'm pretty sure that
trying it will end in coasters.
- Fix a few cases where we were unable to resynchronize with replies
for previous commands. The main thing is to keep reading replies
in case of a stall. This is done with the new state CLRRS.
- Since I am forgetting the basic state machine already, document it.
- Move counter increments in the looping path in its own function.
- Fix a harmless buglet in case CSW read fails to submit: do not
override state.
- Implement the Alan Stern's idea for adaptive signature checking.
Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This smoothes two imperfections:
- Increase number of LUNs per device from 4 to 9. The best solution
would be to remove this limit altogether, but that has to wait until
the time when more than 26 hosts are allowed.
- Replace mdelay with msleep in a probing routine.
Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Pete Zaitcev