Arnd's recent patch series tagged this device with noop_llseek,
conservatively. In fact, it should be no_llseek, which we arrange
for by opening the device with nonseekable_open().
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The existing asm-generic/stat.h specifies st_mtime, etc., as a 32-value,
and works well for 32-bit architectures (currently microblaze, score,
and 32-bit tile). However, for 64-bit architectures it isn't sufficient
to return 32 bits of time_t; this isn't good insurance against the 2037
rollover. (It also makes glibc support less convenient, since we can't
use glibc's handy STAT_IS_KERNEL_STAT mode.)
This change extends the two "timespec" fields for each of the three atime,
mtime, and ctime fields from "int" to "long". As a result, on 32-bit
platforms nothing changes, and 64-bit platforms will now work as expected.
The only wrinkle is 32-bit userspace under 64-bit kernels taking advantage
of COMPAT mode. For these, we leave the "struct stat64" definitions with
the "int" versions of the time_t and nsec fields, so that architectures
can implement compat_sys_stat64() and friends with sys_stat64(), etc.,
and get the expected 32-bit structure layout. This requires a
field-by-field copy in the kernel, implemented by the code guarded
under __ARCH_WANT_STAT64.
This does mean that the shape of the "struct stat" and "struct stat64"
structures is different on a 64-bit kernel, but only one of the two
structures should ever be used by any given process: "struct stat"
is meant for 64-bit userspace only, and "struct stat64" for 32-bit
userspace only. (On a 32-bit kernel the two structures continue to have
the same shape, since "long" is 32 bits.)
The alternative is keeping the two structures the same shape on 64-bit
kernels, which means a 64-bit time_t in "struct stat64" for 32-bit
processes. This is a little unnatural since 32-bit userspace can't
do anything with 64 bits of time_t information, since time_t is just
"long", not "int64_t"; and in any case 32-bit userspace might expect
to be running under a 32-bit kernel, which can't provide the high 32
bits anyway. In the case of a 32-bit kernel we'd then be extending the
kernel's 32-bit time_t to 64 bits, then truncating it back to 32 bits
again in userspace, for no particular reason. And, as mentioned above,
if we have 64-bit time_t for 32-bit processes we can't easily use glibc's
STAT_IS_KERNEL_STAT, since glibc's stat structure requires an embedded
"struct timespec", which is a pair of "long" (32-bit) values in a 32-bit
userspace. "Inventive" solutions are possible, but are pretty hacky.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
The kernel was allowing any component of the pt_regs to be updated either
by signal handlers writing to the stack, or by processes writing via
PTRACE_POKEUSR or PTRACE_SETREGS, which meant they could set their PL
up from 0 to 1 and get access to kernel code and data (or, in practice,
cause a kernel panic). We now always reset the ex1 field, allowing the
user to set their ICS bit only.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change is modelled on similar fixes for other architectures.
The pt_regs "faultnum" member is set to the trap (fault) number that
caused us to enter the kernel, and is INT_SWINT_1 for the syscall software
interrupt. We already supported a pseudo value, INT_SWINT_1_SIGRETURN,
that we used for the rt_sigreturn syscall; it avoided the case where
one signal was handled, then we "tail-called" to another handler.
This change avoids the similar case where we start to call one handler,
then are preempted into another handler when we start trying to run
the first handler. We clear ->faultnum after calling handle_signal(),
and to be paranoid also in the case where there was no signal to deliver.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
For the "initfree" boot argument it's not that big a deal, but
to avoid warnings in the code, we check for a valid value before
allowing the specified argument to override the kernel default.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This completes the tile migration to the new naming scheme for
the architecture-specific irq management code.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change makes KM_TYPE_NR independent of the actual deprecated
list of km_type values, which are no longer used in tile code anywhere.
For now we leave it set to 8, allowing that many nested mappings,
and thus reserving 32MB of address space.
A few remaining places using KM_* values were cleaned up as well.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
* 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6: (38 commits)
kbuild: convert `arch/tile' to the kconfig mainmenu upgrade
README: cite nconfig
Revert "kconfig: Temporarily disable dependency warnings"
kconfig: Use PATH_MAX instead of 128 for path buffer sizes.
kconfig: Fix realloc usage()
kconfig: Propagate const
kconfig: Don't go out from read config loop when you read new symbol
kconfig: fix menuconfig on debian lenny
kbuild: migrate all arch to the kconfig mainmenu upgrade
kconfig: expand file names
kconfig: use the file's name of sourced file
kconfig: constify file name
kconfig: don't emit warning upon rootmenu's prompt redefinition
kconfig: replace KERNELVERSION usage by the mainmenu's prompt
kconfig: delay gconf window initialization
kconfig: expand by default the rootmenu's prompt
kconfig: add a symbol string expansion helper
kconfig: regen parser
kconfig: implement the `mainmenu' directive
kconfig: allow PACKAGE to be defined on the compiler's command-line
...
Fix up trivial conflict in arch/mn10300/Kconfig
Christoph reported a nice splat which illustrated a race in the new stack
based kmap_atomic implementation.
The problem is that we pop our stack slot before we're completely done
resetting its state -- in particular clearing the PTE (sometimes that's
CONFIG_DEBUG_HIGHMEM). If an interrupt happens before we actually clear
the PTE used for the last slot, that interrupt can reuse the slot in a
dirty state, which triggers a BUG in kmap_atomic().
Fix this by introducing kmap_atomic_idx() which reports the current slot
index without actually releasing it and use that to find the PTE and delay
the _pop() until after we're completely done.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reported-by: Christoph Hellwig <hch@infradead.org>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
arch/tile: convert a BUG_ON to BUILD_BUG_ON
arch/tile: make ptrace() work properly for TILE-Gx COMPAT mode
arch/tile: support new info op generated by compiler
arch/tile: minor whitespace/naming changes for string support files
arch/tile: enable single-step support for TILE-Gx
arch/tile: parameterize system PLs to support KVM port
arch/tile: add Tilera's <arch/sim.h> header as an open-source header
arch/tile: Bomb C99 comments to C89 comments in tile's <arch/sim_def.h>
arch/tile: prevent corrupt top frame from causing backtracer runaway
arch/tile: various top-level Makefile cleanups
arch/tile: change lower bound on syscall error return to -4095
arch/tile: properly export __mb_incoherent for modules
arch/tile: provide a definition of MAP_STACK
kmemleak: add TILE to the list of supported architectures.
char: hvc: check for error case
arch/tile: Add a warning if we try to allocate too much vmalloc memory.
arch/tile: update some comments to clarify register usage.
arch/tile: use better "punctuation" for VMSPLIT_3_5G and friends
arch/tile: Use <asm-generic/syscalls.h>
tile: replace some BUG_ON checks with BUILD_BUG_ON checks
Keep the current interface but ignore the KM_type and use a stack based
approach.
The advantage is that we get rid of crappy code like:
#define __KM_PTE \
(in_nmi() ? KM_NMI_PTE : \
in_irq() ? KM_IRQ_PTE : \
KM_PTE0)
and in general can stop worrying about what context we're in and what kmap
slots might be appropriate for that.
The downside is that FRV kmap_atomic() gets more expensive.
For now we use a CPP trick suggested by Andrew:
#define kmap_atomic(page, args...) __kmap_atomic(page)
to avoid having to touch all kmap_atomic() users in a single patch.
[ not compiled on:
- mn10300: the arch doesn't actually build with highmem to begin with ]
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix up drivers/gpu/drm/i915/intel_overlay.c]
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
asm-generic/io.h: allow people to override individual funcs
bitops: remove duplicated extern declarations
bitops: make asm-generic/bitops/find.h more generic
asm-generic: kdebug.h: Checkpatch cleanup
asm-generic: fcntl: make exported headers use strict posix types
asm-generic: cmpxchg does not handle non-long arguments
asm-generic: make atomic_add_unless a function
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
vfs: make no_llseek the default
vfs: don't use BKL in default_llseek
llseek: automatically add .llseek fop
libfs: use generic_file_llseek for simple_attr
mac80211: disallow seeks in minstrel debug code
lirc: make chardev nonseekable
viotape: use noop_llseek
raw: use explicit llseek file operations
ibmasmfs: use generic_file_llseek
spufs: use llseek in all file operations
arm/omap: use generic_file_llseek in iommu_debug
lkdtm: use generic_file_llseek in debugfs
net/wireless: use generic_file_llseek in debugfs
drm: use noop_llseek
* git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-irqflags:
Fix IRQ flag handling naming
MIPS: Add missing #inclusions of <linux/irq.h>
smc91x: Add missing #inclusion of <linux/irq.h>
Drop a couple of unnecessary asm/system.h inclusions
SH: Add missing consts to sys_execve() declaration
Blackfin: Rename IRQ flags handling functions
Blackfin: Add missing dep to asm/irqflags.h
Blackfin: Rename DES PC2() symbol to avoid collision
Blackfin: Split the BF532 BFIN_*_FIO_FLAG() functions to their own header
Blackfin: Split PLL code from mach-specific cdef headers
Previously, we tried to pass 64-bit arguments through the
"COMPAT" mode 32-bit syscall API, which turned out not to work
well. Now we just use straight 32-bit arguments in COMPAT mode,
thus requiring individual registers to be read/written with
two syscalls. Of course this is uncommon, since usually all
the registers are read or written at once.
The restructuring applies to all the tile platforms, but is
plausibly better than the original code in any case.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Our internal process shares memcpy, memset, etc., with libc, and
we did some minor tweaking as part of moving from uclibc to glibc,
which is now reflected in the kernel versions of these files.
There are no semantic changes in this commit, just whitespace
(memcpy_32.S now properly uses tabs), naming (memmove.c instead
of memmove_32.c, since TILE-Gx shares the file with TILEPro),
and a couple of other minor tweaks.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This is not quite the complete support, since we're not yet shipping
intvec_64.S, but it is the support relevant to the set of files we are
currently shipping, and makes it easier to track changes between
our internal sources and our public GIT repository.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Chris Metcalf
Linus Torvalds
Arnaud Lacombe
Zimny Lech
Namhyung Kim
FUJITA Tomonori
Peter Zijlstra