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
Convert files to UTF-8 and some cleanups
2007-10-19 23:21:04 +02:00
[ARM] 4913/1: [AT91] PMC_MDIV definitions
2008-04-10 14:57:20 +01:00
[ARM] Use new get_irqnr_preamble
2007-05-12 15:25:50 +01:00
[ARM] 4185/2: entry: introduce get_irqnr_preamble and arch_ret_to_user
2007-02-17 15:04:29 +00:00
[ARM] 4634/1: DaVinci GPIO header build fix
2007-10-31 15:21:52 +00:00
[ARM] Use new get_irqnr_preamble
2007-05-12 15:25:50 +01:00
[ARM] Use new get_irqnr_preamble
2007-05-12 15:25:50 +01:00
[ARM] 4988/1: Add GPIO lib support to the EP93xx
2008-04-19 14:01:43 +01:00
[ARM] 4185/2: entry: introduce get_irqnr_preamble and arch_ret_to_user
2007-02-17 15:04:29 +00:00
imxfb: fast read flag and nonstandard field configurable
2007-10-16 09:43:21 -07:00
[ARM] Remove Integrator/CP SMP platform support
2007-05-16 15:35:26 +01:00
iop-adma: remove the workaround for missed interrupts on iop3xx
2008-04-17 13:25:54 -07:00
[ARM] 4476/1: EM7210/SS4000E support
2007-07-20 09:35:35 +01:00
iop3xx: surface the iop3xx DMA and AAU units to the iop-adma driver
2007-07-13 08:06:19 -07:00
Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
2008-02-04 15:29:53 -08:00
[ARM] 4680/1: parentheses around NR_IRQS definition
2007-11-29 20:56:57 +00:00
[ARM] 4185/2: entry: introduce get_irqnr_preamble and arch_ret_to_user
2007-02-17 15:04:29 +00:00
[ARM] 4981/1: [KS8695] Simple LED driver
2008-04-17 15:58:25 +01:00
[ARM] 4185/2: entry: introduce get_irqnr_preamble and arch_ret_to_user
2007-02-17 15:04:29 +00:00
[ARM] 4248/1: lh7a40x: fix missing definitions for get_irqnr_preamble
2007-03-08 13:33:57 +00:00
[ARM] msm: dma support for MSM7X00A
2008-01-26 14:39:14 +00:00
[ARM] 4887/1: i.MXC family: Separate current platform code
2008-04-17 16:15:17 +01:00
[ARM] 4329/1: fix position of NETX_SYSTEM_REG
2007-05-03 20:22:49 +01:00
ns9xxx: let putc autodetect where to write
2008-03-31 08:17:01 +02:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc
2008-04-21 17:23:30 -07:00
Orion: orion -> orion5x rename
2008-03-27 14:51:41 -04:00
[ARM] 4185/2: entry: introduce get_irqnr_preamble and arch_ret_to_user
2007-02-17 15:04:29 +00:00
[MTD] [NAND] support for pxa3xx
2008-04-22 19:27:27 +01:00
RealView: Add uncompressing support for PB1176
2008-04-18 22:43:16 +01:00
[ARM] 4564/1: Add tagged list support for Acorn RiscPC's uncompress code
2007-10-12 23:43:11 +01:00
[ARM] 4522/1: S3C: split include/asm-arm/arch/memory.h
2007-07-22 17:06:04 +01:00
Merge branch 'merge-fixes' into devel
2008-04-19 17:17:34 +01:00
ide: add struct ide_io_ports (take 3)
2008-04-27 15:38:32 +02:00
[ARM] 4185/2: entry: introduce get_irqnr_preamble and arch_ret_to_user
2007-02-17 15:04:29 +00:00
fix typo 'the same the\>'
2008-02-03 14:59:11 +02:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/juhl/trivial
2008-04-21 16:36:46 -07:00
iop: unconditionally initialize the ATU on platforms known to be 'hosts'
2008-03-26 12:33:41 -07:00
plat-orion: make orion_nand available for all Orion families
2008-03-27 14:51:40 -04:00
[MTD] [NAND] S3C2410 Allow ECC disable to be specified by the board
2008-04-22 21:41:32 +01:00
[ARM] 4786/1: S3C2412: Add SPI FIFO controll constants
2008-01-28 13:20:51 +00:00
[ARM] 4216/1: add .gitignore entries for ARM specific files
2007-02-17 11:26:41 +00:00
aout: suppress A.OUT library support if !CONFIG_ARCH_SUPPORTS_AOUT
2008-02-08 09:22:30 -08:00
aout: move STACK_TOP[_MAX] to asm/processor.h
2008-02-08 09:22:29 -08:00
atomic.h: atomic_add_unless as inline. Remove system.h atomic.h circular dependency
2007-05-08 11:15:20 -07:00
ext4: Add ext4_find_next_bit()
2008-01-28 23:58:27 -05:00
[ARM] 3983/2: remove unused argument to __bug()
2006-12-07 22:38:09 +00:00
[ARM] Marvell Feroceon CPU core support
2008-01-26 15:03:38 +00:00
[ARM] Improve csum_fold, cleanup csum_tcpudp_magic()
2007-02-06 16:46:46 +00:00
[ARM] 3978/1: macro to provide a 63-bit value from a 32-bit hardware counter
2006-12-07 16:06:45 +00:00
Add a prefetch abort handler
2008-04-18 22:43:07 +01:00
[ARM] Unuse another Linux PTE bit
2006-12-13 14:34:43 +00:00
[ARM] Add a reference from struct device to the dma bounce info
2007-02-12 10:28:24 +00:00
[NET]: div64_64 consolidate (rev3)
2007-04-25 22:23:33 -07:00
arm: sg fallout
2007-10-23 12:37:59 +02:00
[ARM] 4127/1: Flush the prefetch buffer after changing the DACR
2007-02-08 14:49:18 +00:00
[ARM] ecard: add ecardm_iomap() / ecardm_iounmap()
2007-05-11 17:19:02 +01:00
Cleanup asm/{elf,page,user}.h: #ifdef __KERNEL__ is no longer needed
2008-02-07 08:42:30 -08:00
fbdev: detect primary display device
2007-07-17 10:23:11 -07:00
[ARM] nommu: fix breakage caused by f9720205d1
2007-10-31 15:21:42 +00:00
cleanup floppy.h
2007-10-17 08:42:55 -07:00
[ARM] 4583/1: ARMv7: Add VFPv3 support
2008-01-26 14:41:28 +00:00
Add a prefetch abort handler
2008-04-18 22:43:07 +01:00
[PATCH] GPIO core
2007-02-12 09:48:34 -08:00
ARMv7: Add support for the ThumbEE state saving/restoring
2008-04-18 22:43:06 +01:00
ide: remove ide_default_io_ctl() macro
2008-04-18 00:46:34 +02:00
endianness annotations in arm io.h
2007-10-14 12:41:52 -07:00
[ARM] enable arbitary speed tty ioctls and split input/output speed
2007-05-28 23:07:34 +01:00
[ARM] 4073/1: Prevent s3c24xx drivers from including asm/arch/hardware.h and asm/arch/irqs.h
2006-12-30 17:05:07 +00:00
[ARM] 4473/2: Take the HWCAP definitions out of the elf.h file
2007-07-12 16:20:15 +01:00
move die notifier handling to common code
2007-05-08 11:15:04 -07:00
[ARM] 4838/1: Fix kexec for SA1100 machines
2008-02-29 22:47:09 +00:00
Kprobes: indicate kretprobe support in Kconfig
2008-03-04 16:35:11 -08:00
kvm: provide kvm.h for all architecture: fixes headers_install
2008-04-02 15:28:18 -07:00
[ARM] VFP: fix section mismatch error
2007-06-10 12:22:20 +01:00
[ARM] Add initial sparsemem support
2008-04-19 11:36:48 +01:00
[ARM] ARMv6: add CPU_HAS_ASID configuration
2007-05-17 10:19:23 +01:00
[ARM] ARMv6: add CPU_HAS_ASID configuration
2007-05-17 10:19:23 +01:00
misc: removal of final callers using fastcall
2008-02-08 09:22:31 -08:00
CONFIG_HIGHPTE vs. sub-page page tables.
2008-02-08 09:22:42 -08:00
[ARM] 4577/1: ITE 8152 PCI bridge support
2007-10-15 18:53:59 +01:00
CONFIG_HIGHPTE vs. sub-page page tables.
2008-02-08 09:22:42 -08:00
[ARM] 4850/1: include generic pgtable.h for !CONFIG_MMU case
2008-03-06 12:18:18 +00:00
mm: introduce pte_special pte bit
2008-04-28 08:58:23 -07:00
Consolidate asm/poll.h
2007-05-11 08:29:34 -07:00
asm-*/posix_types.h: scrub __GLIBC__
2008-02-08 09:22:34 -08:00
[ARM] include/asm-arm - use angle brackets for includes
2008-03-06 12:18:18 +00:00
aout: move STACK_TOP[_MAX] to asm/processor.h
2008-02-08 09:22:29 -08:00
[ARM] Move HWCAP_* definitions to asm/elf.h
2006-11-30 12:24:46 +00:00
[ARM] 4474/1: Do not check the PSR_F_BIT in valid_user_regs
2007-07-12 16:20:52 +01:00
Add CONFIG_DEBUG_SG sg validation
2007-10-22 21:20:03 +02:00
Generic semaphore implementation
2008-04-17 10:42:34 -04:00
[ARM] use __used attribute
2007-05-30 13:15:06 +01:00
[ARM] 4372/1: Define byte sizes in asm-arm/sizes.h
2007-05-11 21:07:58 +01:00
[ARM] 4814/1: RealView: Add broadcasting clockevents support for ARM11MPCore
2008-02-04 17:52:19 +00:00
[NET]: Introducing socket mark socket option.
2008-01-31 19:27:19 -08:00
[NET]: Introduce SIOCGSTAMPNS ioctl to get timestamps with nanosec resolution
2007-04-25 22:24:04 -07:00
[ARM] Add initial sparsemem support
2008-04-19 11:36:48 +01:00
[PATCH] Remove the last reference to rwlock_is_locked() macro.
2007-02-11 10:51:34 -08:00
Add cmpxchg_local to arm
2008-02-07 08:42:31 -08:00
[ARM] enable arbitary speed tty ioctls and split input/output speed
2007-05-28 23:07:34 +01:00
[ARM] enable arbitary speed tty ioctls and split input/output speed
2007-05-28 23:07:34 +01:00
ARMv7: Add support for the ThumbEE state saving/restoring
2008-04-18 22:43:06 +01:00
add mm argument to pte/pmd/pud/pgd_free
2008-02-05 09:44:18 -08:00
remove unused flush_tlb_pgtables
2007-10-19 11:53:34 -07:00
ARM kprobes: prevent some functions involved with kprobes from being probed
2008-01-26 15:25:17 +00:00
remove strict ansi check from __u64 in asm/types.h
2007-10-17 08:42:53 -07:00
Storage class should be before const qualifier
2007-02-17 20:11:19 +01:00
[ARM] 4837/1: make __get_unaligned_*() return unsigned types
2008-02-29 22:46:48 +00:00
[ARM] 4852/1: Add timerfd_create, timerfd_settime and timerfd_gettime syscall entries
2008-04-19 11:28:06 +01:00
Sanitize the type of struct user.u_ar0
2008-02-07 08:42:30 -08:00
[ARM] 4583/1: ARMv7: Add VFPv3 support
2008-01-26 14:41:28 +00:00
[ARM] 4583/1: ARMv7: Add VFPv3 support
2008-01-26 14:41:28 +00:00
7e675137a8