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| author | Rusty Russell <rusty@rustcorp.com.au> | 2008-12-31 23:05:57 +1030 |
|---|---|---|
| committer | Rusty Russell <rusty@rustcorp.com.au> | 2008-12-31 23:05:57 +1030 |
| commit | 2ca1a615835d9f4990f42102ab1f2ef434e7e89c (patch) | |
| tree | 726cf3d5f29a6c66c44e4bd68e7ebed2fd83d059 /arch/sparc/lib/user_fixup.c | |
| parent | e12f0102ac81d660c9f801d0a0e10ccf4537a9de (diff) | |
| parent | 6a94cb73064c952255336cc57731904174b2c58f (diff) | |
| download | linux-2ca1a615835d9f4990f42102ab1f2ef434e7e89c.tar.gz linux-2ca1a615835d9f4990f42102ab1f2ef434e7e89c.tar.bz2 linux-2ca1a615835d9f4990f42102ab1f2ef434e7e89c.zip | |
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:
arch/x86/kernel/io_apic.c
Diffstat (limited to 'arch/sparc/lib/user_fixup.c')
| -rw-r--r-- | arch/sparc/lib/user_fixup.c | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/arch/sparc/lib/user_fixup.c b/arch/sparc/lib/user_fixup.c new file mode 100644 index 000000000000..05a361b0a1a4 --- /dev/null +++ b/arch/sparc/lib/user_fixup.c @@ -0,0 +1,66 @@ +/* user_fixup.c: Fix up user copy faults. + * + * Copyright (C) 2004 David S. Miller <davem@redhat.com> + */ + +#include <linux/compiler.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/errno.h> +#include <asm/uaccess.h> + +/* Calculating the exact fault address when using + * block loads and stores can be very complicated. + * + * Instead of trying to be clever and handling all + * of the cases, just fix things up simply here. + */ + +static unsigned long compute_size(unsigned long start, unsigned long size, unsigned long *offset) +{ + unsigned long fault_addr = current_thread_info()->fault_address; + unsigned long end = start + size; + + if (fault_addr < start || fault_addr >= end) { + *offset = 0; + } else { + *offset = fault_addr - start; + size = end - fault_addr; + } + return size; +} + +unsigned long copy_from_user_fixup(void *to, const void __user *from, unsigned long size) +{ + unsigned long offset; + + size = compute_size((unsigned long) from, size, &offset); + if (likely(size)) + memset(to + offset, 0, size); + + return size; +} + +unsigned long copy_to_user_fixup(void __user *to, const void *from, unsigned long size) +{ + unsigned long offset; + + return compute_size((unsigned long) to, size, &offset); +} + +unsigned long copy_in_user_fixup(void __user *to, void __user *from, unsigned long size) +{ + unsigned long fault_addr = current_thread_info()->fault_address; + unsigned long start = (unsigned long) to; + unsigned long end = start + size; + + if (fault_addr >= start && fault_addr < end) + return end - fault_addr; + + start = (unsigned long) from; + end = start + size; + if (fault_addr >= start && fault_addr < end) + return end - fault_addr; + + return size; +} |