From 9f9c0382cda2334b35b40b00f4ed9d6f89f37a7b Mon Sep 17 00:00:00 2001 From: Chris Metcalf Date: Fri, 25 Jun 2010 17:00:56 -0400 Subject: 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 Acked-by: Arnd Bergmann --- arch/tile/include/asm/compat.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/tile/include/asm/compat.h') diff --git a/arch/tile/include/asm/compat.h b/arch/tile/include/asm/compat.h index e133c53f6c4..b09292bcc19 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) -- cgit v1.2.3