From the 01408c4939 log message:
The problem is that when we write to a file, the copy from userspace to
pagecache is first done with preemption disabled, so if the source
address is not immediately available the copy fails *and* *zeros* *the*
*destination*.
This is a problem because a concurrent read (which admittedly is an odd
thing to do) might see zeros rather that was there before the write, or
what was there after, or some mixture of the two (any of these being a
reasonable thing to see).
If the copy did fail, it will immediately be retried with preemption
re-enabled so any transient problem with accessing the source won't
cause an error.
The first copying does not need to zero any uncopied bytes, and doing
so causes the problem. It uses copy_from_user_atomic rather than
copy_from_user so the simple expedient is to change copy_from_user_atomic
to *not* zero out bytes on failure.
< --- end cite --- >
This patch finally implements at least a not so pretty solution by
duplicating the relevant part of __copy_user.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The kernel use 64-bit for sc_regs[0], and both N32/N64 userland
expects it was 64-bit. But size of 'long' on N32 is actually 32-bit.
So this definition make some confusion. Use __u32 and __u64 for
N32/N64 sigcontext to get rid of this confusion.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This fixes some sparse warnings.
pgtable-32.c:15:6: warning: symbol 'pgd_init' was not declared. Should it be static?
pgtable-32.c:32:13: warning: symbol 'pagetable_init' was not declared. Should it be static?
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add R2 optimized variants of clear_bit, set_bit and test_and_clear_bit.
With gcc 4.1.1 this saves 1592 bytes on a defconfig (minus IPv6) kernel.
Turns out that R2 bitop instructions are no gain for the other bitop
functions.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This implementation has support for the concept of one separate ioport
address space by PCI domain. A pointer to the virtual address where
the port space of a domain has been mapped has been added to struct
pci_controller and systems should be fixed to fill in this value. For
single domain systems this will be the same value as passed to
set_io_port_base().
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
access_ok in compat-signal.h is wrong (checking destination instead of
source) and redundant (already checked before calling this function).
Also sf_mask in struct sigframe32 should be compat_sigset_t type.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This did result in double clearing of the error return value on success
only but should make a meassurable overhead for sigreturn.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Platforms will now have to supply a function dma_device_is_coherent which
returns if a particular device participates in the coherence domain. For
most platforms this function will always return 0 or 1.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Now that finally all supported versions of binutils have functioning
support for .subsection use .subsection to tweak the branch prediction
I did not modify the R10000 errata variants because it seems unclear if
this will invalidate the workaround which actually relies on the cheesy
prediction of branch likely to cause a misspredict if the sc was
successful.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] signal: do not inline handle_signal()
[MIPS] signal: do not use save_static_function() anymore
[MIPS] signal32: no need to save c0_status register in setup_sigcontext32()
[MIPS] signal32: reduce {setup,restore}_sigcontext32 sizes
[MIPS] signal: factorize debug code
[MIPS] signal: test return value of install_sigtramp()
[MIPS] signal32: remove duplicate code
[MIPS] signal: clean up sigframe structure
[MIPS] signal: do not inline functions in signal-common.h
[MIPS] signals: reduce {setup,restore}_sigcontext sizes
[MIPS] Fix warning in get_user when fetching pointer object from userspace.
[MIPS] Fix eth2 platform device id for jaguar_atx and ocelot_3 platforms
[MIPS] JMR3927 and RBTX49x7 support little endian
[MIPS] RBTX49x7: declare prom_getcmdline()
[MIPS] RTLX: Sprinkle device model code into code to make udev happier.
[MIPS] VPE: Sprinkle device model code into code to make udev happier.
The line discipline numbers N_* are currently defined for each architecture
individually, but (except for a seeming mistake) identically, in
asm/termios.h. There is no obvious reason why these numbers should be
architecture specific, nor any apparent relationship with the termios
structure. The total number of these, NR_LDISCS, is defined in linux/tty.h
anyway. So I propose the following patch which moves the definitions of
the individual line disciplines to linux/tty.h too.
Three of these numbers (N_MASC, N_PROFIBUS_FDL, and N_SMSBLOCK) are unused
in the current kernel, but the patch still keeps the complete set in case
there are plans to use them yet.
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the last vestiges of the long-deprecated "MAP_ANON" page protection
flag: use "MAP_ANONYMOUS" instead.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All the information in the MIPS c0_status register is priviledged.
Nothing that would constitute part of the thread context.
The one flag one could possibly argument about might be c0_status.fr
but none of the ABIs or tools or application software can make use
of it.
So for consistency with restore_sigcontext32(), which does not
restore c0_status register, this patch remove the saving part.
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-apm:
[APM] SH: Convert to use shared APM emulation.
[APM] MIPS: Convert to use shared APM emulation.
[APM] ARM: Convert to use shared APM emulation.
[APM] Add shared version of APM emulation
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-tc:
[EISA] EISA registration with !CONFIG_EISA
[TC] pmagb-b-fb: Convert to the driver model
[TC] dec_esp: Driver model for the PMAZ-A
[TC] mips: pmag-ba-fb: Convert to the driver model
[TC] defxx: TURBOchannel support
[TC] TURBOchannel support for the DECstation
[TC] MIPS: TURBOchannel resources off-by-one fix
[TC] MIPS: TURBOchannel update to the driver model
On all targets that sucker boils down to memcpy_fromio(sbk->data, from, len).
The function name is highly misguiding (it _never_ does any checksums), the
last argument is just a noise and simply expanding the call to memcpy_fromio()
gives shorter and more readable source. For a lot of reasons it has almost
no remaining users, so it's better to just outright kill it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Also convert to use generic kernel/power/Kconfig to make the use of the
shared APM emulation possible.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This is the platform-specific part of TURBOchannel bus support for the
DECstation. It implements determining whether the bus is actually there,
getting bus parameters, IRQ assignments for devices and protected accesses
to possibly unoccupied slots that may trigger bus error exceptions.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This is a set of changes to convert support for the TURBOchannel bus to the
driver model. It implements the usual set of calls similar to what other bus
drivers have: tc_register_driver(), tc_unregister_driver(), etc. All the
platform-specific bits have been removed and headers from asm-mips/dec/ have
been merged into linux/tc.h, which should be included by drivers.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The problem was introduced in 2.6.18.3 with the casting of some
36bit-defines (PCI memory) in au1000.h to resource_size_t which may be
u32 or u64 depending on the experimental CONFIG_RESOURCES_64BIT.
With unset CONFIG_RESOURCES_64BIT, the pci-memory cannot be accessed
because the ioremap in arch/mips/au1000/common/pci.c already used the
truncated addresses.
With set CONFIG_RESOURCES_64BIT, things get even worse, because PCI-scan
aborts, due to resource conflict: request_resource() in arch/mips/pci/pci.c
fails because the maximum iomem-address is 0xffffffff (32bit) but the
pci-memory-start-address is 0x440000000 (36bit).
To get pci working again, I propose the following patch:
1. remove the resource_size_t-casting from au1000.h again
2. make the casting in arch/mips/au1000/common/pci.c (it's allowed and
necessary here. The 36bit-handling will be done in __fixup_bigphys_addr).
With this patch pci works again like in 2.6.18.2, the gcc-compile warnings
in pci.c are gone and it doesn't depend on CONFIG_EXPERIMENTAL.
Signed-off-by: Alexander Bigga <ab@mycable.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
CC arch/mips/au1000/common/pci.o
arch/mips/au1000/common/pci.c:42: warning: large integer implicitly truncated to unsigned type
arch/mips/au1000/common/pci.c:43: warning: large integer implicitly truncated to unsigned type
arch/mips/au1000/common/pci.c:49: warning: large integer implicitly truncated to unsigned type
arch/mips/au1000/common/pci.c:50: warning: large integer implicitly truncated to unsigned type
arch/mips/au1000/common/pci.c: In function ‘au1x_pci_setup’:
arch/mips/au1000/common/pci.c:82: warning: ISO C90 forbids mixed declarations and code
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The old code was assuming that min_low_pfn was always 0. This
means that platforms having a big hole at their memory start
paid the price of wasting some memory for the allocation of
unused entries in mem_map[].
This patch prevents this waste.
It introduces PHYS_OFFSET define which is the start of the
physical memory and uses it wherever needed. Specially when
converting physical/virtual addresses into virtual/physical
ones.
Currently all platforms defines PHYS_OFFSET to 0.
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch makes a better usage of these two globals.
'min_low_pfn' is now correctly setup for all configs, which
allow us to rely on it in boot memory code init.
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Current prom_free_prom_memory() implementations are almost same as
free_init_pages(), or no-op. Make free_init_pages() extern (again)
and make prom_free_prom_memory() use it.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Move I8259A_IRQ_BASE from asm/i8259.h to asm/mach-generic/irq.h and
make it really customizable. And remove I8259_IRQ_BASE declared on
some platforms. Currently only NEC_CMBVR4133 is using custom
I8259A_IRQ_BASE value.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The irq_base for {mips,rm7k,rm9k}_cpu_irq_init() are constant on all
platforms and are same value on most platforms (0 or 16, depends on
CONFIG_I8259). Define them in asm-mips/mach-generic/irq.h and make
them customizable. This will save a few cycle on each CPU interrupt.
A good side effect is removing some dependencies to MALTA in generic
SMTC code.
Although MIPS_CPU_IRQ_BASE is customizable, this patch changes irq
mappings on DDB5477, EMMA2RH and MIPS_SIM, since really customizing
them might cause some header dependency problem and there seems no
good reason to customize it. So currently only VR41XX is using custom
MIPS_CPU_IRQ_BASE value, which is 0 regardless of CONFIG_I8259.
Testing this patch on those platforms is greatly appreciated. Thank
you.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Nick Piggin points out that page accounting on MIPS multiple ZERO_PAGEs
is not maintained by its move_pte, and could lead to freeing a ZERO_PAGE.
Instead of complicating that move_pte, just forget the minor optimization
when mremapping, and change the one thing which needed it for correctness
- filemap_xip use ZERO_PAGE(0) throughout instead of according to address.
[ "There is no block device driver one could use for XIP on mips
platforms" - Carsten Otte ]
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The commit 8e3d8433d8 ([NET]: MIPS
checksum annotations and cleanups) broke 64-bit MIPS.
The problem is the commit replaces some unsigned long with __be32. On
64bit MIPS, a __be32 (i.e. unsigned int) value is represented as a
sign-extented 32-bit value in a 64-bit argument register. So the
address 192.168.0.1 (0xc0a80001) is passed as 0xffffffffc0a80001 to
csum_tcpudp_nofold() but the asm code in the function expects
0x00000000c0a80001, therefore it returns a wrong checksum. Explicit
cast to unsigned long is needed to drop high 32bit.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
NEC VR4111 and VR4121 need one more nop with mtc0_tlbw_hazard().
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
SMTC pseudo-interrupts between TCs are deferred and queued if the target
TC is interrupt-inhibited (IXMT). In the first SMTC prototypes, these
queued IPIs were serviced on return to user mode, or on entry into the
kernel idle loop. The INSTANT_REPLAY option dispatches them as part of
local_irq_restore() processing, which adds runtime overhead (hence the
option to turn it off), but ensures that IPIs are handled promptly even
under heavy I/O interrupt load.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Implement optimized asm version of csum_partial_copy_nocheck,
csum_partial_copy_from_user and csum_and_copy_to_user which can do
calculate and copy in parallel, based on memcpy.S.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Virtually index, physically tagged cache architectures can get away
without cache flushing when forking. This patch adds a new cache
flushing function flush_cache_dup_mm(struct mm_struct *) which for the
moment I've implemented to do the same thing on all architectures
except on MIPS where it's a no-op.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Provide a custom copy_user_highpage() to deal with aliasing issues on
MIPS. It uses kmap_coherent() to map an user page for kernel with same
color. Rewrite copy_to_user_page() and copy_from_user_page() with the
new interfaces to avoid extra cache flushing.
The main part of this patch was originally written by Ralf Baechle;
Atushi Nemoto did the the debugging.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
