Many of the syscalls mentioned in the audit code are not present
for architectures that implement only the "standard" set of
Linux syscalls (e.g. openat, but not open, etc.). This change
adds proper #ifdefs for all those syscalls.
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
They are only applicable for locally-homecached memory ranges, so
change their names to {flush,finv}_buffer_local(). Change inv_buffer()
to just do an mf instead of any kind of fancier barrier, since you're
obviously not going to be waiting for anything once the local homecache
is invalidated.
Fix tilepro.c network driver not to bother calling finv_buffer when
stopping the EPP, but just mf after memset to ensure that it will not
see any packet data after we finish stopping; use finv_buffer_remote()
when doing exit-time cleanup.
This also fixes a (not very interesting) generic Linux build failure
where drivers/scsi/st.c declares its own flush_buffer().
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
User space code has been able to discover the static page size
by including a special <hv/pagesize.h> file. In the current release,
that file is now gone, and <asm/page.h> doesn't rely on it. The
getpagesize() API is now the only way for userspace to get the page size.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change adds a number of missing headers in asm (fb.h, parport.h,
serial.h, and vga.h) using the minimal generic versions.
It also adds a number of missing interfaces that showed up as build
failures when trying to build various drivers not normally included in the
"tile" distribution: ioremap_wc(), memset_io(), io{read,write}{16,32}be(),
virt_to_bus(), bus_to_virt(), irq_canonicalize(), __pte(), __pgd(),
and __pmd(). I also added a cast in virt_to_page() since not all callers
pass a pointer.
I fixed <asm/stat.h> to properly include a __KERNEL__ guard for the
__ARCH_WANT_STAT64 symbol, and <asm/swab.h> to use __builtin_bswap32()
even for our 64-bit architecture, since the same code is produced.
I added an export for get_cycles(), since it's used in some modules.
And I made <arch/spr_def.h> properly include the __KERNEL__ guard,
even though it's not yet exported, since it likely will be soon.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Otherwise, it's possible to end up with the prefetcher pulling
data into cache that the code believes has been flushed.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Otherwise, in principle, there could be stale I$ data present
next time the page that previously held the kernel module code was
used to run some new code.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This allows processes to spread more effectively to multiple cores
(particularly important on 64-core chips!).
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This semantic was already true for atomic operations within the kernel,
and this change makes it true for the fast atomic syscalls (__NR_cmpxchg
and __NR_atomic_update) as well. Previously, user-space had to use
the fast atomic syscalls exclusively to update memory, since raw stores
could lose a race with the atomic update code even when the atomic update
hadn't actually modified the value.
With this change, we no longer write back the value to memory if it
hasn't changed. This allows certain types of idioms in user space to
work as expected, e.g. "atomic exchange" to acquire a spinlock, followed
by a raw store of zero to release the lock.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This support is required for CONFIG_KEYS, NFSv4 kernel DNS, etc.
The change is slightly more complex than the minimal thing, since
I took advantage of having to go into the assembly code to just
move a bunch of stuff into C code: specifically, the schedule(),
do_async_page_fault(), do_signal(), and single_step_once() support,
in addition to the TIF_NOTIFY_RESUME support.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change is the result of some work to make the backtrace code more
shareable between kernel, libc, and gdb.
For the kernel, some good effects are to eliminate the hacky
"VirtualAddress" typedef in favor of "unsigned long", to eliminate a
bunch of spurious kernel doc comments, to remove the dead "bt_read_memory"
function, and to use "__tilegx__" in #ifdefs instead of "TILE_CHIP".
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Commit 8d7718aa08 changed "int"
to "u32" in the prototypes but not the definition.
I missed this when I saw the patch go by on LKML.
We cast "u32 *" to "int *" since we are tying into the underlying
atomics framework, and atomic_t uses int as its value type.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Reviewed-by: Michel Lespinasse <walken@google.com>
This change supports building the kernel with newer binutils where
a shift of greater than the word size is no longer interpreted
silently as modulo the word size, but instead generates a warning.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The first issue fixed in this patch is that pending rwlock write locks
could lock out new readers; this could cause a deadlock if a read lock was
held on cpu 1, a write lock was then attempted on cpu 2 and was pending,
and cpu 1 was interrupted and attempted to re-acquire a read lock.
The write lock code was modified to not lock out new readers.
The second issue fixed is that there was a narrow race window where a tns
instruction had been issued (setting the lock value to "1") and the store
instruction to reset the lock value correctly had not yet been issued.
In this case, if an interrupt occurred and the same cpu then tried to
manipulate the lock, it would find the lock value set to "1" and spin
forever, assuming some other cpu was partway through updating it. The fix
is to enforce an interrupt critical section around the tns/store pair.
In addition, this change now arranges to always validate that after
a readlock we have not wrapped around the count of readers, which
is only eight bits.
Since these changes make the rwlock "fast path" code heavier weight,
I decided to move all the rwlock code all out of line, leaving only the
conventional spinlock code with fastpath inlines. Since the read_lock
and read_trylock implementations ended up very similar, I just expressed
read_lock in terms of read_trylock.
As part of this change I also eliminate support for the now-obsolete
tns_atomic mode.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Add tile support for the EDAC driver, which provides unified system
error (memory, PCI, etc.) reporting. For now, the TILEPro port
reports memory correctable error (CE) only.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Combine the "command" and "completion" locks into a single lock,
on each egress queue, to improve efficiency.
Support the use of 4KB pages in the "egress queue".
Delete the unused "duplicate ACK compression" code.
Filter "bad" (i.e. truncated) packets.
Avoid corrupting "dev->napi_list", by sequentializing modifications.
Deregister for incoming packets during stop, to reduce unexpected
interrupts. Also, encourage active NAPI loops to complete before
we disable NAPI, which would otherwise crash.
Free any pending completions after shutting down LEPP.
Use a single, permanently registered, IRQ handler, to avoid situations
in which the IRQ handler was firing after being freed, and ignore any
"unexpected" interrupts.
Drop egress packets, instead of spinning, if the hardware cannot keep
up, or is disconnected.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The Tilera architecture traditionally supports 64KB page sizes
to improve TLB utilization and improve performance when the
hardware is being used primarily to run a single application.
For more generic server scenarios, it can be beneficial to run
with 4KB page sizes, so this commit allows that to be specified
(by modifying the arch/tile/include/hv/pagesize.h header).
As part of this change, we also re-worked the PTE management
slightly so that PTE writes all go through a __set_pte() function
where we can do some additional validation. The set_pte_order()
function was eliminated since the "order" argument wasn't being used.
One bug uncovered was in the PCI DMA code, which wasn't properly
flushing the specified range. This was benign with 64KB pages,
but with 4KB pages we were getting some larger flushes wrong.
The per-cpu memory reservation code also needed updating to
conform with the newer percpu stuff; before it always chose 64KB,
and that was always correct, but with 4KB granularity we now have
to pay closer attention and reserve the amount of memory that will
be requested when the percpu code starts allocating.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This renames 3G_OPT to 2_75G, and adds 2_5G and 2_25G.
For memory-intensive applications that are also network-buffer
intensive it can be helpful to be able to tune the virtual address
of the start of kernel memory.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This is a grab bag of changes with no actual change to generated code.
This includes whitespace and comment typos, plus a couple of stale
comments being removed.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
It now takes an additional argument so it can be used to
flush-and-invalidate pages that are cached using hash-for-home
as well those that are cached with coherence point on a single cpu.
This allows it to be used more widely for changing the coherence
point of arbitrary pages when necessary.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The first is that we were using an incorrect hand-rolled variant
of __kernel_text_address() which didn't handle module PCs. We now
just use the standard API.
The second was that we weren't accounting for the three-level
page table when we were trying to pre-verify the addresses on
the 64-bit TILE-Gx processor; we now do that correctly.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This avoids having to maintain an additional separate assembly
file, and of course the inline is slightly more efficient as well.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Previously we used iret to atomically return to kernel PL with
interrupts enabled. However, it turns out that we are architecturally
guaranteed that we can just set and clear the "interrupt critical
section" and only interrupt on the following instruction, so we
now do that instead, since it's cleaner.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
These headers are used by Linux but are maintained upstream.
This change incorporates a few minor fixes to these headers,
including a new sim_print() function, cleaner support for the
sim_syscall() API, and a sim_query_cpu_speed() method.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
As the added comment says, we can sometimes see a coherence warning
from our simulator if the "swapper_pgprot" variable on the boot cpu
has not been evicted from cache by the time the other cpus come up.
Force it to be evicted so we never see the warning.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This should have been as part of the initial hardwall submission to
LKML but was overlooked. The header provides the ioctl definitions for
manipulating the hardwall fd, so needs to be available to userspace.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Previously we assumed this was impossible, but in fact it can happen.
Handle it gracefully by retrying after issuing a warning.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The problem was that this could lead to IPIs being disabled during
the softirq processing after a hypervisor downcall (e.g. for I/O),
since both IPI and device interrupts use the INCTRL_1 downcall mechanism.
When this happened at the wrong time, it could lead to deadlock.
Luckily, we were already maintaining the per-interrupt state we need,
and using it in the proper way in the hypervisor, so all we had to do
was to change Linux to stop blocking downcall interrupts for the entire
length of the downcall. (Now they're blocked while we're executing the
downcall routine itself, but not while we're executing any subsequent
softirq routines.) The hypervisor is doing a very small amount of
work it no longer needs to do (masking INTCTRL_1 on entry to the client
interrupt routine), but doing so means that older versions of Tile Linux
will continue to work with a current hypervisor, so that seems reasonable.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The current implementations of __ndelay and __udelay call a hypervisor
service to delay, but the hypervisor service isn't actually implemented
very well, and the consensus is that Linux should handle figuring this
out natively and not use a hypervisor service.
By converting nanoseconds to cycles, and then spinning until the
cycle counter reaches the desired cycle, we get several benefits:
first, we are sensitive to the actual clock speed; second, we use
less power by issuing a slow SPR read once every six cycles while
we delay; and third, we properly handle the case of an interrupt by
exiting at the target time rather than after some number of cycles.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
To handle single-step, tile mmap's a page of memory in the process
space for each thread and uses it to construct a version of the
instruction that we want to single step. If the process exec's,
though, we lose that mapping, and the kernel needs to be aware that
it will need to recreate it if the exec'ed process than tries to
single-step as well.
Also correct some int32_t to s32 for better kernel style.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The convention changed to, e.g., ".data..page_aligned". This commit
fixes the places in the tile architecture that were still using the
old convention. One tile-specific section (.init.page) was dropped
in favor of just using an "aligned" attribute.
Sam Ravnborg <sam@ravnborg.org> pointed out __PAGE_ALIGNED_BSS, etc.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This adds the volatile cast which forces the compiler to emit the load.
Suggested by Peter Zijlstra <peterz@infradead.org>.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The current tile rt_sigreturn() syscall pattern uses the common idiom
of loading up pt_regs with all the saved registers from the time of
the signal, then anticipating the fact that we will clobber the ABI
"return value" register (r0) as we return from the syscall by setting
the rt_sigreturn return value to whatever random value was in the pt_regs
for r0.
However, this breaks in our 64-bit kernel when running "compat" tasks,
since we always sign-extend the "return value" register to properly
handle returned pointers that are in the upper 2GB of the 32-bit compat
address space. Doing this to the sigreturn path then causes occasional
random corruption of the 64-bit r0 register.
Instead, we stop doing the crazy "load the return-value register"
hack in sigreturn. We already have some sigreturn-specific assembly
code that we use to pass the pt_regs pointer to C code. We extend that
code to also set the link register to point to a spot a few instructions
after the usual syscall return address so we don't clobber the saved r0.
Now it no longer matters what the rt_sigreturn syscall returns, and the
pt_regs structure can be cleanly and completely reloaded.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Previously we were just setting up the "tp" register in the
new task as started by clone() in libc. However, this is not
quite right, since in principle a signal might be delivered to
the new task before it had its TLS set up. (Of course, this race
window still exists for resetting the libc getpid() cached value
in the new task, in principle. But in any case, we are now doing
this exactly the way all other architectures do it.)
This change is important for 2.6.37 since the tile glibc we will
be submitting upstream will not set TLS in user space any more,
so it will only work on a kernel that has this fix. It should
also be taken for 2.6.36.x in the stable tree if possible.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: stable <stable@kernel.org>
This change fixes a bug that memchr() will read the first word
of the source even if the length is zero. Ironically, the code
was originally written with a test to avoid exactly this problem,
but to make the code conform to Linux coding standards with all
declarations preceding all statements, the first load from memory
was moved up above that test as the initial value for a variable.
The change just moves all the variable declarations to the top
of the file, with no initializers, so that the test can also be
at the top of the file.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
glibc assumes that it can count /sys/devices/system/cpu/cpu* to get
the number of configured cpus. For this to be valid on tile, we need
to generate a "cpu" entry for all cpus, including the ones that are
not currently allocated for Linux's use.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change enables PCI root complex support for TILEPro. Unlike
TILE-Gx, TILEPro has no support for memory-mapped I/O, so the PCI
support consists of hypervisor upcalls for PIO, DMA, etc. However,
the performance is fine for the devices we have tested with so far
(1Gb Ethernet, SATA, etc.).
The <asm/io.h> header was tweaked to be a little bit more aggressive
about disabling attempts to map/unmap IO port space. The hacky
<asm/pci-bridge.h> header was rolled into the <asm/pci.h> header
and the result was simplified. Both of the latter two headers were
preliminary versions not meant for release before now - oh well.
There is one quirk for our TILEmpower platform, which accidentally
negotiates up to 5GT and needs to be kicked down to 2.5GT.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change adds the first network driver for the tile architecture,
supporting the on-chip XGBE and GBE shims.
The infrastructure is present for the TILE-Gx networking drivers (another
three source files in the new directory) but for now the the actual
tilegx sources are waiting on releasing hardware to initial customers.
Note that arch/tile/include/hv/* are "upstream" headers from the
Tilera hypervisor and will probably benefit less from LKML review.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This avoids a deadlock in the IGMP code where one core gets a read
lock, another core starts trying to get a write lock (thus blocking
new readers), and then the first core tries to recursively re-acquire
the read lock.
We still try to preserve some degree of balance by giving priority
to additional write lockers that come along while the lock is held
for write, so they can all complete quickly and return the lock to
the readers.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
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>
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>
While not a port to KVM (yet), this change modifies the kernel
to be able to build either at PL1 or at PL2 with a suitable
config switch. Pushing up this change avoids handling branch
merge issues going forward with the KVM work.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change adds one of the Tilera standard <arch> headers to the set
of headers shipped with Linux. The <arch/sim.h> header provides
methods for programmatically interacting with the Tilera simulator.
The current <arch/sim.h> provides inline assembly for the _sim_syscall
function, so the declaration and definition previously provided
manually in Linux are no longer needed. We now use the standard
sim_validate_lines_evicted() method from <arch/sim.h> rather than
rolling our own direct call to sim_syscall().
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The backtracer will normally cut itself off after 100 frames anyway,
but it's messy. With this change we notice that the frame being
reported is the same as the last one, and cut off the dump with a
message similar to what gdb displays in the same circumstance.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Avoid a compile failure if CONFIG_DEBUG_EXTRA_FLAGS is empty ("");
provide an "install" hook as well as a matching archhelp target;
and some minor whitespace cleanup.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Previously we were using -1023, which is fine for normal syscall
error returns, but the common value in use for other platforms
is -4095, and one Tilera-specific driver does use values in the
-1100 range, so tickled this bug.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
It's convenient for userspace (in particular, glibc) to find a
definition of MAP_STACK. We use MAP_GROWSDOWN as an alias since
that's appropriate for the main stack, and since our current
allocation of mmap flags bits is running a bit short otherwise.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
All the necessary functionality was already there; we just need
to make it possible to select the config option.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
With this change we now include <asm-generic/syscalls.h> into the "tile"
version of the header. To take full advantage of the prototypes there,
we also change our naming convention for "struct pt_regs *" syscalls so
that, e.g., _sys_execve() is the "true" syscall entry, which sets the
appropriate register to point to the pt_regs before calling sys_execve().
While doing this I realized I no longer needed the fork and vfork
entry point stubs, since those functions aren't in the generic
syscall ABI, so I removed them as well.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This "bpt_code" instruction was killed off in our development line a while
ago (the actual definition of bpt_code that is used is in kernel/traps.c)
but I didn't push it for 2.6.36 because it seemed harmless and I didn't
want to try to push more than absolutely necessary.
However, we recently fixed a bug in our gcc that had been causing
"-gdwarf2" not to be passed to the assembler, and passing this flag causes
an erroneous assembler failure in the presence of code in a data section,
sometimes. While we'd like to track down the bug in the assembler,
we'd also like to make sure 2.6.36 builds with the current toolchain,
so I'm removing this dead code as well.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This cut-and-paste bug was caused by rewriting the register dump
code to use only a single printk per line of output.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
During context switch, save and restore a couple of additional bits of
tilegx user state that can be persistently modified by userspace.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Rather than just using pt_regs, it now contains the actual saved
state explicitly, similar to pt_regs. By doing it this way, we
provide a cleaner API for userspace (or equivalently, we avoid the
need for libc to provide its own definition of sigcontext).
While we're at it, move PT_FLAGS_xxx to where they are not visible
from userspace. And always pass siginfo and mcontext to signal
handlers, even if they claim they don't need it, since sometimes
they actually try to use it anyway in practice.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The sys_execve() implementation was properly const-ified but not
the declaration, the syscall wrappers, or the compat version.
This change completes the constification process.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
With this change, the arch/tile Makefile will only check for a valid
combination of CROSS_COMPILE vs "uname -m" for a few common targets
that are typically the ones we get wrong (vmlinux, all, and modules).
The change handles the case of an empty "make" goal like "make all".
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
This fixes a failure in "make headers_check" for tile.
I hadn't realized this file was exported to userspace by default.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Until now, the tile architecture ABI for syscall return has just been
that r0 holds the return value, and an error is only signalled like it is
for kernel code, with a negative small number.
However, this means that in multiple places in userspace we end up writing
the same three-cycle idiom that tests for a small negative number for
error. It seems cleaner to instead move that code into the kernel, and
set r1 to hold zero on success or errno on failure; previously, r1 was
just zeroed on return from the kernel (to avoid leaking kernel state).
This way a single conditional branch after the syscall is sufficient
to test for the failure case. The number of cycles taken is the same,
but the error-checking code is in just one place, so total code size is
smaller, and random userspace syscall code is easier to understand.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change rolls up random cleanups not representing any actual bugs.
- Remove a stale CONFIG_ value from the default tile_defconfig
- Remove unused tns_atomic_xxx() family of methods from <asm/atomic.h>
- Optimize get_order() using Tile's "clz" instruction
- Fix a bad hypervisor upcall name (not currently used in Linux anyway)
- Use __copy_in_user_inatomic() name for consistency, and export it
- Export some additional hypervisor driver I/O upcalls and some homecache calls
- Remove the obfuscating MEMCPY_TEST_WH64 support code
- Other stray comment cleanups, #if 0 removal, etc.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This functionality was stubbed out until recently. Now we support our
normal backtracing API on TILE-Gx as well as on TILE64/TILEPro.
This change includes a tweak to the instruction encoding caused by
adding addxli for compat mode.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
First, the siginfo preamble wasn't quite right; we need to indicate
that we are padding up to 4 ints of preamble for 64-bit code, and
then for compat mode we need to pad differently, using only 3 ints.
Second, the C ABI requires a save area of two registers, not two
pointers, since in compat mode we have 64-bit registers all of which
we need to save, even though we only have 32-bit VAs.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
We were using the same 5-sec minsec for the clocksource and sched_clock
that we were using for the clock_event_device. For the clock_event_device
that's exactly right since it has a short maximum countdown time.
But for sched_clock we want to avoid wraparound when converting from
ticks to nsec over a much longer window, so we force a shift of 10.
And for clocksource it seems dodgy to use a 5-sec minsec as well, so we
copy some other platforms and force a shift of 22.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The use of "hvc_con_driver" as the name for a file-static "struct
console" with a ".setup" field pointing to an __init function causes
a modpost warning, since a non-initdata structure points to init code.
Using "hvc_console" as the name triggers the hacky "*_console"
workaround in modpost to silence the warning, and is the same thing
that most of the other console drivers already do.
I made the same change in hvsi.c since I happened to notice it was
likely to suffer from the same problem.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
None of these changes fix any actual bugs, but are just various cleanups
that fell out along the way. In particular, some unused #defines and
includes are removed, PREFETCH_STRIDE is added (the default is right for
our shipping chips, but wrong for our next generation), our tile-specific
prefetching code is removed so the (identical) generic prefetching code
can be used instead, a comment is fixed to be proper GPL and not just a
"paste GPL here" token, a "//" comment is converted to "/* */", etc.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
This commit is primarily changes caused by reviewing "sparse"
and "checkpatch" output on our sources, so is somewhat noisy, since
things like "printk() -> pr_err()" (or whatever) throughout the
codebase tend to get tedious to read. Rather than trying to tease
apart precisely which things changed due to which type of code
review, this commit includes various cleanups in the code:
- sparse: Add declarations in headers for globals.
- sparse: Fix __user annotations.
- sparse: Using gfp_t consistently instead of int.
- sparse: removing functions not actually used.
- checkpatch: Clean up printk() warnings by using pr_info(), etc.;
also avoid partial-line printks except in bootup code.
- checkpatch: Use exposed structs rather than typedefs.
- checkpatch: Change some C99 comments to C89 comments.
In addition, a couple of minor other changes are rolled in
to this commit:
- Add support for a "raise" instruction to cause SIGFPE, etc., to be raised.
- Remove some compat code that is unnecessary when we fully eliminate
some of the deprecated syscalls from the generic syscall ABI.
- Update the tile_defconfig to reflect current config contents.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
This code is used in other places in our system than in Linux, so
to share it we now implement it as an inline function in our low-level
<arch> headers, and instantiate it in one file in Linux's arch/tile/lib.
The file is now cacheflush.c and is C code rather than the strangely-named
and assembler-implemented __invalidate_icache.S.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
This wasn't properly tested until the perf-event subsystem started
to get brought up under the tile architecture.
The bug caused bogus atomic64_cmpxchg() values to be returned,
among other things.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
The C file (tile-desc_{32,64}.c) was about 300KB before this change,
and is now shrunk down to 100K. The original file included support
for BFD in the binutils toolchain, which is not necessary in the
kernel; the kernel version only needs to include enough support to
enable the single-stepper and backtracer.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>