s/device_ptr_t/device_t/g
No md5 changes in the .o's
# Note to the md5 tracking club: $FreeBSD$ changes md5 after every commit
# so you need to checkout -kk to get $FreeBSD$ instead of the actual value
# of the keyword.
host controllers to avoid the need to allocate any multi-page
physically contiguous memory blocks. This makes it possible to use
USB devices reliably on low-memory systems or when memory is too
fragmented for contiguous allocations to succeed.
The USB subsystem now uses bus_dmamap_load() directly on the buffers
supplied by USB peripheral drivers, so this also avoids having to
copy data back and forth before and after transfers. The ehci and
ohci controllers support scatter/gather as long as the buffer is
contiguous in the virtual address space. For uhci the hardware
cannot handle a physical address discontinuity within a USB packet,
so it is necessary to copy small memory fragments at times.
skip blocks that are too big by a factor of two or greater. This
avoids some cases of extremely inefficient memory use that can occur
when large (e.g. 64k) blocks on the free list get used when allocating
a 4k chunk of 64-byte fragments. Because fragments have their own
free list, the 60k difference got lost forever every time.
allocation function. With this patch, it prevents continous growth of
the devbuf memory pool.
Tested with ssh <host> dd of=/dev/null < /dev/zero and vmstat -m | grep devbuf
go looking for free fragments won't match. Since we never free this, we
can "throw away" the tag. This is very dirty, and needs to be reimplemented
properly, but fixes performance problems with uhci.
Also assert that when we overlay a structure on some space, that the
space is large enough for the structure.
