It has been noticed that across a kernel build many calls to
tlb_flush_mmu() do not have anything to flush, apparently because glibc
is mmapping a file over a previously-mapped region which has no
faulted-in ptes.

This patch detects this case and optimises away a little over one third
of the tlb invalidations.

The functions which potentially cause an invalidate are
tlb_remove_tlb_entry(), pte_free_tlb() and pmd_free_tlb().  These have
been front-ended in asm-generic/tlb.h and the per-arch versions now
have leading double-underscores.  The generic versions tag the
mmu_gather_t as needing a flush and then call the arch-specific
version.

tlb_flush_mmu() looks at tlb->need_flush and if it sees that no real
activity has happened, the invalidation is avoided.

The success rate is displayed in /proc/meminfo for the while.  This
should be removed later.

- Kill duplicate debug check

- Add a test for pages which have a pte_chain coming off the buddy lists.

Some day gcc may drop support for __FUNCTION__ entirely, we'll
just add a #define __FUNCTION__ __func__ at that point. In the
meantime, gcc-3.x warns about pasting __FUNCTION__, so don't do it.

This came up in 2.5.30, apparently someone was fooled by names
which do not quite match actual functions.

add_gendisk()/del_gendisk() moved into ->reinit() and ->cleanup() of
ide-{disk,cd,floppy} - i.e.  moments when high-levle driver claims/gives
up a drive.

register_disk() also shifted into ->reinit().

consequently, revalidate_drives() is gone (it did messy postponed
rereading of partition tables; not needed anymore).  Ditto for
ide_geninit().

regular 2.5 changes in ->revalidate() and BLKRRPART handling - same as
all other block devices.

instead of messing with ide_module_t, we put ide_driver_t themselves on
a (cyclic) list - said list being the only use of ide_module_t for
high-level drivers.  ide_register_module()/ide_unregister_module() takes
ide_driver_t now (renamed to ide_register_driver()).  /proc/ide/drivers
switched to use of that cyclic list and uses seq_file instead of old
home-grown code.

->init() for high-level drivers is never called (other than as
module_init() when they are initialized).  Method removed, instances
cleaned up.

ide_reinit_drive() turned into ata_attach().  Said beast takes a drive,
tries to feed it to high-level drivers and drops it on the ata_unused if
nobody claims the sucker.  IOW, that's what ide_register_module() used
to do, but for a single drive.

ideprobe_init() calls ata_attach() instead of putting on ata_unused.

ide_register_module() eliminated.  Some of the callers do not need it
anymore, some (ide_replace_subdriver()) actually want ata_attach(drive).

ide_scan_devices() is gone.  There were two remaining callers - in
ide_register_module() and ide_unregister_module().  The former had been
turned into "put driver on the list, empty ata_unused into temporary
list and call ata_attach() on all drives there".  The latter is "remove
driver from the list, call ->cleanup() and ata_attach() for all drives"
(->cleanup() gives the drive up, ata_attach() gives the remaining
drivers a shot for that drive; if nobody claims it - it's put on
ata_unused).

->owner added to ide_driver_t.  MOD_INC_USE_COUNT/MOD_DEC_USE_COUNT
taken out of ->reinit().  ide_reinit_drive() turned into "call
->reinit() for all high-level drivers that are registered until somebody
claims the drive" (instead of open-coded variant in 2.5.32; cleaner and
works correctly for modular drivers).

loops in ide_cdrom_init()/ide_cdrom_exit(), etc. are pulled into
ide_register_module()/ide_unregister_module() resp.

Duplicate calls of ide_cdrom_init(), idedisk_init(), etc. are removed
from ide_init_builtin_drivers() (they were called both from there (i.e.
from ide_init()) and later as module_init() for high-level drivers).

Checks for media type, ->driver_req, etc.  are moved from the
ide_scan_devices() to ->reinit().  ide_scan_devices() had lost first two
arguments (it will completely disappear later).

This puts drives on cyclic lists - per-driver ones for drives that had
been claimed by high-level drivers and ata_unused for unclaimed drives.
We put drives on ata_unused in the very end of ideprobe_init() and then
move them to drivers' lists as they are claimed.

Finish introduction of ->reinit() - Jens had missed MOD_DEC_USE_COUNT on
several exits from ide-cd one and forgot to remove the loop from
ide-floppy ide-tape and ide-scsi ones ;-) (->reinit() is the body of
loop in ->init() - stuff that should be done one drive; in 2.5.32
ide-disk one is OK, ide-cd is OK modulo minor bugs and in the rest it's
a copy of ->init())

Move stuff from ide_register_subdriver() (associating drive with
high-level driver) to ide-probe.c, so that remaining stuff can be safely
called in parallel with IO on other drives [Andre]

This adds list_for_each_entry, which is the equivalent of list_for_each
and list_entry, except only one variable is needed.

Just pushes the BKL down a little, no big deal.

This optimisation is really noticeable as it avoids having to take the
BKL on every close().

 - remove elf_caddr_t. It's positively dangerous to #define this since
   elf_caddr_t foo, bar; creates variables of different types (foo is
   char *, bar is char).
 - rewrite large chunks of create_elf_tables(), it needed cleaning anyway.
 - add upwards-growing stack support to create_elf_tables.
 - redefine the ARCH_DLINFO stuff on powerpc -- it's tested, works.
 - add upwards-growing-stack support to exec.c too.

into home.transmeta.com:/home/torvalds/v2.5/linux

and one USB net driver:  3c574_cs, ibmtr_cs, pcnet_cs, ray_cs,
xirc2ps_cs, xircom_cb, and usb/net/kaweth

return EOPNOTSUPP if no eeprom present, in ETHTOOL_SEEPROM ioctl

(thanks for DaveM for advice and help)

* fix tx checksumming (it's still ifdef'd out by default)
* bump version to 0.2.0
* ifdef out dev->change_mtu support, it is reported broken.

o Feature: Merged NAPI support from Robert Olsson

o Bug fix: moved tx_timeout processing from interrupt context 
  to process context so h/w controller reset can busy-wait.

o Bug fix: ethtool SSET and NWAY we're broken when !netif_running.
o Cleanup: removed PPC code optimization - not needed.
o Bug fix: workaround for Dell Avalon system: change descriptor
  write-back policy to write back 16 bytes rather than 8 bytes.
o Bug fix: added mwb() to force memory transaction ordering on ia-64.
o Cleanup: misc. whitespace cleanup.

o Feature: added new interrupt mitigation knobs.

o Change license from Dual BSD/GPL to GPL

o Forward port of changes from 2.4.20-pre4:
   o ethtool security fixes from Alan Cox
   o usec_delay to udelay (Jeff Garzik)
   o #include <linux/sched.h> for Alpha (Jeff Garzik)

into mandrakesoft.com:/home/jgarzik/repo/net-drivers-2.5

o Bug fix: ethernet bridging not working
o Bug fix: mii-diag does not update driver's speed, 
  duplex, and flow control
o Bug fix: ethtool shows wrong speed/duplex when not connected
o Bug fix: ethtool shows wrong speed/duplex when reconnected if
  forced speed/duplex
o Bug fix: ethtool PHY loopback diagnostic fails