diff options
author | Chris Metcalf <cmetcalf@tilera.com> | 2010-06-25 17:00:56 -0400 |
---|---|---|
committer | Chris Metcalf <cmetcalf@tilera.com> | 2010-07-06 13:34:15 -0400 |
commit | 9f9c0382cda2334b35b40b00f4ed9d6f89f37a7b (patch) | |
tree | 8d862fd0883343e8788f86b8f7d37823db0e19a5 /arch/tile/include/asm/compat.h | |
parent | fb702b942bf638baa6cbbbda9f76794db62921ef (diff) |
arch/tile: Add driver to enable access to the user dynamic network.
This network (the "UDN") connects all the cpus on the chip in a
wormhole-routed dynamic network. Subrectangles of the chip can
be allocated by a "create" ioctl on /dev/hardwall, and then to access the
UDN in that rectangle, tasks must perform an "activate" ioctl on that
same file object after affinitizing themselves to a single cpu in
the region. Sending a wormhole-routed message that tries to leave
that subrectangle causes all activated tasks to receive a SIGILL
(just as they would if they tried to access the UDN without first
activating themselves to a hardwall rectangle).
The original submission of this code to LKML had the driver
instantiated under /proc/tile/hardwall. Now we just use a character
device for this, conventionally /dev/hardwall. Some futures planning
for the TILE-Gx chip suggests that we may want to have other types of
devices that share the general model of "bind a task to a cpu, then
'activate' a file descriptor on a pseudo-device that gives access to
some hardware resource". As such, we are using a device rather
than, for example, a syscall, to set up and activate this code.
As part of this change, the compat_ptr() declaration was fixed and used
to pass the compat_ioctl argument to the normal ioctl. So far we limit
compat code to 2GB, so the difference between zero-extend and sign-extend
(the latter being correct, eventually) had been overlooked.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/tile/include/asm/compat.h')
-rw-r--r-- | arch/tile/include/asm/compat.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/tile/include/asm/compat.h b/arch/tile/include/asm/compat.h index e133c53f6c4f..b09292bcc19f 100644 --- a/arch/tile/include/asm/compat.h +++ b/arch/tile/include/asm/compat.h @@ -222,7 +222,7 @@ struct compat_shmid64_ds { static inline void __user *compat_ptr(compat_uptr_t uptr) { - return (void __user *)(unsigned long)uptr; + return (void __user *)(long)(s32)uptr; } static inline compat_uptr_t ptr_to_compat(void __user *uptr) |