linux/include/asm-mips
Nick Piggin 7e675137a8 mm: introduce pte_special pte bit
s390 for one, cannot implement VM_MIXEDMAP with pfn_valid, due to their memory
model (which is more dynamic than most).  Instead, they had proposed to
implement it with an additional path through vm_normal_page(), using a bit in
the pte to determine whether or not the page should be refcounted:

vm_normal_page()
{
	...
        if (unlikely(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP))) {
                if (vma->vm_flags & VM_MIXEDMAP) {
#ifdef s390
			if (!mixedmap_refcount_pte(pte))
				return NULL;
#else
                        if (!pfn_valid(pfn))
                                return NULL;
#endif
                        goto out;
                }
	...
}

This is fine, however if we are allowed to use a bit in the pte to determine
refcountedness, we can use that to _completely_ replace all the vma based
schemes.  So instead of adding more cases to the already complex vma-based
scheme, we can have a clearly seperate and simple pte-based scheme (and get
slightly better code generation in the process):

vm_normal_page()
{
#ifdef s390
	if (!mixedmap_refcount_pte(pte))
		return NULL;
	return pte_page(pte);
#else
	...
#endif
}

And finally, we may rather make this concept usable by any architecture rather
than making it s390 only, so implement a new type of pte state for this.
Unfortunately the old vma based code must stay, because some architectures may
not be able to spare pte bits.  This makes vm_normal_page a little bit more
ugly than we would like, but the 2 cases are clearly seperate.

So introduce a pte_special pte state, and use it in mm/memory.c.  It is
currently a noop for all architectures, so this doesn't actually result in any
compiled code changes to mm/memory.o.

BTW:
I haven't put vm_normal_page() into arch code as-per an earlier suggestion.
The reason is that, regardless of where vm_normal_page is actually
implemented, the *abstraction* is still exactly the same. Also, while it
depends on whether the architecture has pte_special or not, that is the
only two possible cases, and it really isn't an arch specific function --
the role of the arch code should be to provide primitive functions and
accessors with which to build the core code; pte_special does that. We do
not want architectures to know or care about vm_normal_page itself, and
we definitely don't want them being able to invent something new there
out of sight of mm/ code. If we made vm_normal_page an arch function, then
we have to make vm_insert_mixed (next patch) an arch function too. So I
don't think moving it to arch code fundamentally improves any abstractions,
while it does practically make the code more difficult to follow, for both
mm and arch developers, and easier to misuse.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Carsten Otte <cotte@de.ibm.com>
Cc: Jared Hulbert <jaredeh@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:23 -07:00
..
dec zs: move to the serial subsystem 2007-07-18 08:38:22 -07:00
emma2rh [MIPS] Define MIPS_CPU_IRQ_BASE in generic header 2007-02-06 16:53:08 +00:00
fw [MIPS] CFE: Make code remotely resemble Linux code. 2008-01-29 10:14:55 +00:00
ip32 [MIPS] IP32: More interrupt renumbering fixes. 2007-11-26 17:26:13 +00:00
jmr3927 [MIPS] txx9tmr clockevent/clocksource driver 2007-10-29 19:35:35 +00:00
lasat [MIPS] Lasat: Fix overlap of interrupt number ranges. 2007-11-15 23:21:50 +00:00
mach-atlas [MIPS] SNI: Fix mc146818_decode_year 2007-03-04 19:02:31 +00:00
mach-au1x00 au1xxx-ide: fix MWDMA support 2008-04-26 22:25:22 +02:00
mach-bcm47xx [MIPS] Deforest the function pointer jungle in the time code. 2007-10-11 23:46:08 +01:00
mach-cobalt [MIPS] remove unneeded button check for reset 2008-01-29 10:15:00 +00:00
mach-db1x00 Pb1200/DBAu1200: fix bad IDE resource size 2008-04-17 01:14:33 +02:00
mach-dec [MIPS] Split up war.h 2007-10-11 23:46:07 +01:00
mach-emma2rh [MIPS] Split up war.h 2007-10-11 23:46:07 +01:00
mach-excite include/asm-mips/: Spelling fixes 2008-02-03 16:57:20 +02:00
mach-generic ide: remove ide_init_default_irq() macro 2008-04-18 00:46:35 +02:00
mach-ip22 [MIPS] Split up war.h 2007-10-11 23:46:07 +01:00
mach-ip27 [MIPS] IP27: Tighten up CPU description to fix warnings. 2008-03-12 14:14:41 +00:00
mach-ip28 [MIPS] IP28 support 2008-01-29 10:14:58 +00:00
mach-ip32 [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
mach-jazz [MIPS] Fix and cleanup the MIPS part of the (ab)use of CLOCK_TICK_RATE. 2007-11-02 16:13:48 +00:00
mach-jmr3927 [MIPS] Fix plat_ioremap for JMR3927 2008-03-12 14:14:41 +00:00
mach-lasat [MIPS] Lasat: fix LASAT_CASCADE_IRQ 2008-03-12 14:14:42 +00:00
mach-lemote [MIPS] Split up war.h 2007-10-11 23:46:07 +01:00
mach-mips [MIPS] Split up war.h 2007-10-11 23:46:07 +01:00
mach-mipssim [MIPS] Split up war.h 2007-10-11 23:46:07 +01:00
mach-pb1x00 Pb1200/DBAu1200: fix bad IDE resource size 2008-04-17 01:14:33 +02:00
mach-pnx8550 [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
mach-rm [MIPS] Fix and cleanup the MIPS part of the (ab)use of CLOCK_TICK_RATE. 2007-11-02 16:13:48 +00:00
mach-sibyte [MIPS] Split up war.h 2007-10-11 23:46:07 +01:00
mach-tx49xx [MIPS] Split up war.h 2007-10-11 23:46:07 +01:00
mach-vr41xx [MIPS] Split up war.h 2007-10-11 23:46:07 +01:00
mach-wrppmc include/asm-mips/: Spelling fixes 2008-02-03 16:57:20 +02:00
mach-yosemite [MIPS] Split up war.h 2007-10-11 23:46:07 +01:00
mips-boards [MIPS] Malta, Atlas: move an extern function declaration to the header file 2008-01-29 10:15:05 +00:00
pci Fix misspellings of "system", "controller", "interrupt" and "necessary". 2007-10-19 23:10:43 +02:00
pmc-sierra/msp71xx [MIPS] Delete CONFIG_MSP_FPGA 2008-01-29 10:15:01 +00:00
sgi include/asm-mips/: Spelling fixes 2008-02-03 16:57:20 +02:00
sibyte [MIPS] Remove CONFIG_SIBYTE_PT{1120,1125,SWARM} 2008-01-29 10:14:58 +00:00
sn include/asm-mips/: Spelling fixes 2008-02-03 16:57:20 +02:00
tx4927 [MIPS] TXx9 watchdog support for rbhma3100,rbhma4200,rbhma4500 2008-01-29 10:14:58 +00:00
tx4938 [MIPS] txx9tmr clockevent/clocksource driver 2007-10-29 19:35:35 +00:00
vr41xx [MIPS] Separate platform_device registration for VR41xx GPIO 2007-07-12 17:41:15 +01:00
xtalk [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
a.out.h aout: move STACK_TOP[_MAX] to asm/processor.h 2008-02-08 09:22:29 -08:00
abi.h [MIPS] signals: Share even more code. 2007-02-18 21:31:35 +00:00
addrspace.h [MIPS] Put cast inside macro instead of all the callers 2008-01-29 10:14:55 +00:00
asm.h [MIPS] IP28: added cache barrier to assembly routines 2008-01-29 10:14:58 +00:00
asmmacro-32.h
asmmacro-64.h
asmmacro.h [MIPS] Fix "no space between function name and open parenthesis" warnings. 2007-10-11 23:46:15 +01:00
atomic.h [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
auxvec.h
barrier.h [MIPS] Make support for weakly ordered LL/SC a config option. 2007-07-20 18:57:39 +01:00
bcache.h [MIPS] SNI: remove unused pcimt_scache.c 2007-08-27 02:16:54 +01:00
bitops.h generic: implement __fls on all 64-bit archs 2008-04-26 19:21:16 +02:00
bootinfo.h [MIPS] RM: Collected changes 2008-01-29 10:14:59 +00:00
branch.h
break.h
bug.h [MIPS] Fix BUG(), BUG_ON() handling 2007-04-20 14:58:37 +01:00
bugs.h [MIPS] R4000/R4400 errata workarounds 2008-01-29 10:14:54 +00:00
byteorder.h [MIPS] Fix "no space between function name and open parenthesis" warnings. 2007-10-11 23:46:15 +01:00
cache.h
cachectl.h
cacheflush.h [MIPS] Handle aliases in vmalloc correctly. 2008-04-07 22:31:04 +01:00
cacheops.h [MIPS] Cacheops.h: Fix typo. 2008-01-15 01:04:42 +00:00
checksum.h [MIPS] Fix wrong checksum for split TCP packets on 64-bit MIPS 2007-04-20 14:58:37 +01:00
cmpxchg.h Add cmpxchg64 and cmpxchg64_local to mips 2008-02-07 08:42:30 -08:00
compat-signal.h [MIPS] use compat_siginfo in rt_sigframe_n32 2007-06-26 19:57:33 +02:00
compat.h asm-*/compat.h: fix typo in comment 2008-02-03 16:32:51 +02:00
compiler.h [MIPS] cpu-bugs64.c: GCC 3.3 constraint workaround 2007-09-19 19:33:14 +01:00
cpu-features.h [MIPS] Fix use of smp_processor_id() in preemptible code. 2007-12-01 00:39:37 +00:00
cpu-info.h [MIPS] MT: Scheduler support for SMT 2008-01-29 10:14:57 +00:00
cpu.h [MIPS] Alchemy: Au1210/Au1250 CPU support 2008-01-29 10:14:59 +00:00
cputime.h
current.h
debug.h
delay.h [MIPS] R4000/R4400 daddiu erratum workaround 2008-01-29 10:14:55 +00:00
device.h Driver core: add dev_archdata to struct device 2006-12-01 14:52:01 -08:00
div64.h [MIPS] Change names of local variables to silence sparse 2007-07-10 17:33:06 +01:00
dma-mapping.h [MIPS] Don't claim we support dma_declare_coherent_memory - we don't. 2007-02-13 22:40:50 +00:00
dma.h [MIPS] IP28 support 2008-01-29 10:14:58 +00:00
ds1286.h
dsp.h
edac.h [MIPS] Polish <asm/edac.h>. 2007-08-27 02:16:59 +01:00
elf.h Cleanup asm/{elf,page,user}.h: #ifdef __KERNEL__ is no longer needed 2008-02-07 08:42:30 -08:00
emergency-restart.h
errno.h
fb.h fbdev: detect primary display device 2007-07-17 10:23:11 -07:00
fcntl.h [MIPS] Fix value of O_TRUNC 2007-10-01 14:17:50 +01:00
fixmap.h [MIPS] fixmap: delete unused __set_fixmap, set_fixmap and set_fixmap_nocache 2008-01-29 10:15:00 +00:00
floppy.h cleanup floppy.h 2007-10-17 08:42:55 -07:00
fpregdef.h
fpu_emulator.h
fpu.h remove asm/bitops.h includes 2007-10-19 11:53:41 -07:00
futex.h [MIPS] Fix possible hang in LL/SC futex loops. 2007-11-26 17:26:14 +00:00
gdb-stub.h
gpio.h [MIPS] Add generic GPIO support 2007-07-10 17:32:55 +01:00
gt64120.h [MIPS] time: Add GT641xx timer0 clockevent driver 2007-10-22 22:09:00 +01:00
hardirq.h
hazards.h [MIPS] R1: Fix hazard barriers to make kernels work on R2 also. 2007-10-11 23:46:19 +01:00
highmem.h [MIPS] Fix yosemite build error 2008-03-12 14:14:42 +00:00
hw_irq.h [MIPS] i8295 cleanups. 2007-10-11 23:46:04 +01:00
i8253.h [MIPS] Fix pcspeaker build. 2007-11-26 17:26:13 +00:00
i8259.h [MIPS] i8295 cleanups. 2007-10-11 23:46:04 +01:00
ide.h
inst.h [MIPS] Fix rdhwr_op definition. 2006-07-13 21:26:08 +01:00
inventory.h [MIPS] Fix "no space between function name and open parenthesis" warnings. 2007-10-11 23:46:15 +01:00
io.h Remove dma_cache_(wback|inv|wback_inv) functions 2007-10-17 08:42:57 -07:00
ioctl.h [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
ioctls.h [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
ipcbuf.h
irq_cpu.h [MIPS] Define MIPS_CPU_IRQ_BASE in generic header 2007-02-06 16:53:08 +00:00
irq_gt641xx.h [MIPS] Add GT641xx IRQ routines. 2007-10-11 23:46:04 +01:00
irq_regs.h [MIPS] Complete fixes after removal of pt_regs argument to int handlers. 2006-10-08 02:38:28 +01:00
irq.h [MIPS] IRQ Affinity Support for SMTC on Malta Platform 2007-10-11 23:45:57 +01:00
irqflags.h [MIPS] Fix "no space between function name and open parenthesis" warnings. 2007-10-11 23:46:15 +01:00
isadep.h
jazz.h [MIPS] JAZZ fixes 2007-10-11 23:46:00 +01:00
jazzdma.h [MIPS] JAZZ fixes 2007-10-11 23:46:00 +01:00
Kbuild [MIPS] Have headers_install install <asm/cachectl.h> and <asm/sysmips.h>. 2006-09-27 13:37:56 +01:00
kdebug.h move die notifier handling to common code 2007-05-08 11:15:04 -07:00
kexec.h kdump/kexec: calculate note size at compile time 2007-05-08 11:15:07 -07:00
kmap_types.h
kspd.h
kvm.h kvm: provide kvm.h for all architecture: fixes headers_install 2008-04-02 15:28:18 -07:00
linkage.h [MIPS] Sibyte: Replace SB1 cachecode with standard R4000 class cache code. 2007-10-11 23:46:05 +01:00
local.h [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
m48t35.h
m48t37.h
mc146818-time.h [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
mc146818rtc.h
mips_mt.h [MIPS] MT: Enable coexistence of AP/SP with VSMP and SMTC. 2007-07-31 21:35:24 +01:00
mipsmtregs.h [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
mipsprom.h [MIPS] RM: Collected changes 2008-01-29 10:14:59 +00:00
mipsregs.h [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
mman.h [PATCH] Remove final references to deprecated "MAP_ANON" page protection flag 2007-02-11 10:51:17 -08:00
mmu_context.h [MIPS] Kill num_online_cpus() loops. 2007-10-11 23:46:18 +01:00
mmu.h
mmzone.h [PATCH] Delete unused definitions of kvaddr_to_nid 2006-06-23 07:42:52 -07:00
module.h [MIPS] define Hit_Invalidate_I to Index_Invalidate_I for loongson2 2007-07-10 17:33:02 +01:00
msc01_ic.h [MIPS] MT: Reenable EIC support and add support for SOCit SC. 2007-05-11 14:28:31 +01:00
msgbuf.h
mutex.h
namei.h
nile4.h [MIPS] Add back support for LASAT platforms 2007-10-11 23:46:00 +01:00
paccess.h [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
page.h CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
param.h
parport.h [MIPS] Fix "no space between function name and open parenthesis" warnings. 2007-10-11 23:46:15 +01:00
pci.h [MIPS] PCI: Always enable CONFIG_PCI_DOMAINS 2007-10-11 23:46:03 +01:00
percpu.h
pgalloc.h CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
pgtable-32.h [MIPS] Fix yosemite build error 2008-03-12 14:14:42 +00:00
pgtable-64.h [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
pgtable-bits.h
pgtable.h mm: introduce pte_special pte bit 2008-04-28 08:58:23 -07:00
pmon.h [MIPS] PMON: Fix cpustart declaration. 2007-07-31 21:35:32 +01:00
poll.h Consolidate asm/poll.h 2007-05-11 08:29:34 -07:00
posix_types.h asm-*/posix_types.h: scrub __GLIBC__ 2008-02-08 09:22:34 -08:00
prctl.h [MIPS] Fix "no space between function name and open parenthesis" warnings. 2007-10-11 23:46:15 +01:00
prefetch.h
processor.h aout: move STACK_TOP[_MAX] to asm/processor.h 2008-02-08 09:22:29 -08:00
ptrace.h [MIPS] IP22: Fix warning. 2007-10-16 18:23:47 +01:00
r4kcache.h [MIPS] Use real cache invalidate 2008-01-29 10:14:57 +00:00
reboot.h
reg.h
regdef.h
resource.h
rm9k-ocd.h
rtlx.h [MIPS] RTLX: Handle copy_*_user return values. 2007-03-17 01:03:29 +00:00
scatterlist.h Add CONFIG_DEBUG_SG sg validation 2007-10-22 21:20:03 +02:00
seccomp.h [MIPS] Fixup secure computing stuff. 2007-07-31 21:35:21 +01:00
sections.h [MIPS] Remove _fdata from asm-mips/sections.h 2007-02-06 16:53:15 +00:00
segment.h
semaphore.h Generic semaphore implementation 2008-04-17 10:42:34 -04:00
sembuf.h
serial.h [MIPS] Put an end to <asm/serial.h>'s long and annyoing existence 2007-07-10 17:33:01 +01:00
setup.h [PATCH] cleanup asm/setup.h userspace visibility 2006-12-07 08:39:46 -08:00
sgialib.h [MIPS] Fix and cleanup the mess that a dozen prom_printf variants are. 2007-03-04 19:02:37 +00:00
sgiarcs.h [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
sgidefs.h
shmbuf.h
shmparam.h
sigcontext.h [MIPS] Add basic SMARTMIPS ASE support 2007-02-22 00:50:44 +00:00
siginfo.h [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
signal.h [MIPS] signals: Share even more code. 2007-02-18 21:31:35 +00:00
sim.h [MIPS] Fix "no space between function name and open parenthesis" warnings. 2007-10-11 23:46:15 +01:00
smp-ops.h [MIPS] SMP: Call platform methods via ops structure. 2008-01-29 10:14:57 +00:00
smp.h [MIPS] SMP: Call platform methods via ops structure. 2008-01-29 10:14:57 +00:00
smtc_ipi.h [MIPS] SMTC: Fix build error. 2008-01-22 00:35:23 +00:00
smtc_proc.h
smtc.h [MIPS] SMTC: Move MIPS_CPU_IPI_IRQ definition into header. 2007-08-27 02:16:55 +01:00
sni.h [MIPS] RM: fix EISA=n compilation 2008-02-19 17:01:34 +00:00
socket.h [NET]: Introducing socket mark socket option. 2008-01-31 19:27:19 -08:00
sockios.h [NET]: Introduce SIOCGSTAMPNS ioctl to get timestamps with nanosec resolution 2007-04-25 22:24:04 -07:00
sparsemem.h
spinlock_types.h
spinlock.h [MIPS] Make support for weakly ordered LL/SC a config option. 2007-07-20 18:57:39 +01:00
stackframe.h [MIPS] R4000/R4400 daddiu erratum workaround 2008-01-29 10:14:55 +00:00
stacktrace.h [MIPS] unwind_stack should return a value ... 2007-08-27 02:16:55 +01:00
stat.h
statfs.h
string.h
suspend.h
sysmips.h
system.h IP22ZILOG: fix lockup and sysrq 2007-11-29 09:24:53 -08:00
termbits.h [MIPS] tty: add the new ioctls and definitions. 2007-09-10 21:25:27 +01:00
termios.h [MIPS] tty: add the new ioctls and definitions. 2007-09-10 21:25:27 +01:00
thread_info.h Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus 2007-07-31 20:41:53 -07:00
time.h [MIPS] Clocksource: Only install r4k counter as clocksource if present. 2008-03-12 14:14:42 +00:00
timex.h [MIPS] Change get_cycles to always return 0. 2007-11-15 23:21:49 +00:00
titan_dep.h
tlb.h
tlbdebug.h [MIPS] Cleanup tlbdebug.h 2007-07-12 17:41:11 +01:00
tlbflush.h remove unused flush_tlb_pgtables 2007-10-19 11:53:34 -07:00
topology.h [MIPS] MT: Scheduler support for SMT 2008-01-29 10:14:57 +00:00
traps.h
txx9irq.h [MIPS] The irq_chip for TX39/TX49 SoCs 2007-08-27 02:16:52 +01:00
txx9tmr.h [MIPS] txx9tmr clockevent/clocksource driver 2007-10-29 19:35:35 +00:00
types.h remove strict ansi check from __u64 in asm/types.h 2007-10-17 08:42:53 -07:00
uaccess.h [MIPS] R4000/R4400 daddiu erratum workaround 2008-01-29 10:14:55 +00:00
ucontext.h
unaligned.h [MIPS] Optimize get_unaligned / put_unaligned implementations. 2007-10-11 23:46:15 +01:00
unistd.h [MIPS] Wire up the timerfd_*() o32 system calls 2008-02-19 17:01:31 +00:00
user.h Sanitize the type of struct user.u_ar0 2008-02-07 08:42:30 -08:00
vga.h [MIPS] checkfiles: Fix "need space after that ','" errors. 2007-10-11 23:46:15 +01:00
vpe.h
war.h [MIPS] R4000/R4400 errata workarounds 2008-01-29 10:14:54 +00:00
wbflush.h
xor.h