- remove special treatment of pager_map mappings in pmaps. this is
required now, since I've removed the globals that expose the address range.
pager_map now uses pmap_kenter_pa() instead of pmap_enter(), so there's
no longer any need to special-case it.
- eliminate struct uvm_vnode by moving its fields into struct vnode.
- rewrite the pageout path. the pager is now responsible for handling the
high-level requests instead of only getting control after a bunch of work
has already been done on its behalf. this will allow us to UBCify LFS,
which needs tighter control over its pages than other filesystems do.
writing a page to disk no longer requires making it read-only, which
allows us to write wired pages without causing all kinds of havoc.
- use a new PG_PAGEOUT flag to indicate that a page should be freed
on behalf of the pagedaemon when it's unlocked. this flag is very similar
to PG_RELEASED, but unlike PG_RELEASED, PG_PAGEOUT can be cleared if the
pageout fails due to eg. an indirect-block buffer being locked.
this allows us to remove the "version" field from struct vm_page,
and together with shrinking "loan_count" from 32 bits to 16,
struct vm_page is now 4 bytes smaller.
- no longer use PG_RELEASED for swap-backed pages. if the page is busy
because it's being paged out, we can't release the swap slot to be
reallocated until that write is complete, but unlike with vnodes we
don't keep a count of in-progress writes so there's no good way to
know when the write is done. instead, when we need to free a busy
swap-backed page, just sleep until we can get it busy ourselves.
- implement a fast-path for extending writes which allows us to avoid
zeroing new pages. this substantially reduces cpu usage.
- encapsulate the data used by the genfs code in a struct genfs_node,
which must be the first element of the filesystem-specific vnode data
for filesystems which use genfs_{get,put}pages().
- eliminate many of the UVM pagerops, since they aren't needed anymore
now that the pager "put" operation is a higher-level operation.
- enhance the genfs code to allow NFS to use the genfs_{get,put}pages
instead of a modified copy.
- clean up struct vnode by removing all the fields that used to be used by
the vfs_cluster.c code (which we don't use anymore with UBC).
- remove kmem_object and mb_object since they were useless.
instead of allocating pages to these objects, we now just allocate
pages with no object. such pages are mapped in the kernel until they
are freed, so we can use the mapping to find the page to free it.
this allows us to remove splvm() protection in several places.
The sum of all these changes improves write throughput on my
decstation 5000/200 to within 1% of the rate of NetBSD 1.5
and reduces the elapsed time for "make release" of a NetBSD 1.5
source tree on my 128MB pc to 10% less than a 1.5 kernel took.
device (rather, the device that carries that attribute) also
carry one or more attributes indicating which type of controller
it might be.
This will allow systems that might have AGP, but would never have
e.g. an Intel PCI-Host bridge, to trim out code that won't be used.
attach time. Allow access to these regions in vga_pci_mmap().
Note: we also have to allow access to the legacy ISA "hole" in
vga_pci_mmap(), since the X server needs to be able to read
the legacy BIOS on many cards.
XXX Need to address the PCI Expansion ROM.
Based on changes from Simon Burge <simonb@wasabisystems.com>.
-Add a really bad hack: The X server (4.1.0 afaict) appearently overwrites
the PGTBL_CTL which contains the base address of the pseudo-GATT.
Restore the original value if we notice this happened.
The X server works now, but only with soft cursor.
-allocate space for DMA segments as much as necessary
-fix format warnings in a debug output
-don't try to access AGP capability stuff in the PCI config header
if it doesn't exist (as on the i810)
function on all (probed) PCI buses:
int pci_find_device(struct pci_attach_args *pa,
int (*match)(struct pci_attach_args *));
The pci_attach_args structure pointed to by pa is filled in if the
device is found, and 1 is returned. Otherwise 0 is returned.
This function is, unfortunately, needed by the i810 agp code. It's
also of use for LKMs.
Also frob pci_probe_bus to take 2 extra args when used by pci_find_device.
