4522d58275
* 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6: (156 commits) [PATCH] x86-64: Export smp_call_function_single [PATCH] i386: Clean up smp_tune_scheduling() [PATCH] unwinder: move .eh_frame to RODATA [PATCH] unwinder: fully support linker generated .eh_frame_hdr section [PATCH] x86-64: don't use set_irq_regs() [PATCH] x86-64: check vector in setup_ioapic_dest to verify if need setup_IO_APIC_irq [PATCH] x86-64: Make ix86 default to HIGHMEM4G instead of NOHIGHMEM [PATCH] i386: replace kmalloc+memset with kzalloc [PATCH] x86-64: remove remaining pc98 code [PATCH] x86-64: remove unused variable [PATCH] x86-64: Fix constraints in atomic_add_return() [PATCH] x86-64: fix asm constraints in i386 atomic_add_return [PATCH] x86-64: Correct documentation for bzImage protocol v2.05 [PATCH] x86-64: replace kmalloc+memset with kzalloc in MTRR code [PATCH] x86-64: Fix numaq build error [PATCH] x86-64: include/asm-x86_64/cpufeature.h isn't a userspace header [PATCH] unwinder: Add debugging output to the Dwarf2 unwinder [PATCH] x86-64: Clarify error message in GART code [PATCH] x86-64: Fix interrupt race in idle callback (3rd try) [PATCH] x86-64: Remove unwind stack pointer alignment forcing again ... Fixed conflict in include/linux/uaccess.h manually Signed-off-by: Linus Torvalds <torvalds@osdl.org>
87 lines
2.4 KiB
C
87 lines
2.4 KiB
C
#ifndef __LINUX_UACCESS_H__
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#define __LINUX_UACCESS_H__
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#include <linux/preempt.h>
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#include <asm/uaccess.h>
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/*
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* These routines enable/disable the pagefault handler in that
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* it will not take any locks and go straight to the fixup table.
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*
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* They have great resemblance to the preempt_disable/enable calls
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* and in fact they are identical; this is because currently there is
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* no other way to make the pagefault handlers do this. So we do
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* disable preemption but we don't necessarily care about that.
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*/
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static inline void pagefault_disable(void)
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{
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inc_preempt_count();
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/*
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* make sure to have issued the store before a pagefault
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* can hit.
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*/
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barrier();
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}
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static inline void pagefault_enable(void)
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{
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/*
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* make sure to issue those last loads/stores before enabling
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* the pagefault handler again.
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*/
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barrier();
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dec_preempt_count();
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/*
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* make sure we do..
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*/
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barrier();
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preempt_check_resched();
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}
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#ifndef ARCH_HAS_NOCACHE_UACCESS
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static inline unsigned long __copy_from_user_inatomic_nocache(void *to,
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const void __user *from, unsigned long n)
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{
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return __copy_from_user_inatomic(to, from, n);
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}
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static inline unsigned long __copy_from_user_nocache(void *to,
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const void __user *from, unsigned long n)
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{
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return __copy_from_user(to, from, n);
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}
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#endif /* ARCH_HAS_NOCACHE_UACCESS */
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/**
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* probe_kernel_address(): safely attempt to read from a location
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* @addr: address to read from - its type is type typeof(retval)*
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* @retval: read into this variable
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*
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* Safely read from address @addr into variable @revtal. If a kernel fault
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* happens, handle that and return -EFAULT.
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* We ensure that the __get_user() is executed in atomic context so that
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* do_page_fault() doesn't attempt to take mmap_sem. This makes
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* probe_kernel_address() suitable for use within regions where the caller
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* already holds mmap_sem, or other locks which nest inside mmap_sem.
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* This must be a macro because __get_user() needs to know the types of the
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* args.
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*
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* We don't include enough header files to be able to do the set_fs(). We
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* require that the probe_kernel_address() caller will do that.
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*/
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#define probe_kernel_address(addr, retval) \
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({ \
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long ret; \
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mm_segment_t old_fs = get_fs(); \
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\
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set_fs(KERNEL_DS); \
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pagefault_disable(); \
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ret = __get_user(retval, (__force typeof(retval) __user *)(addr)); \
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pagefault_enable(); \
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set_fs(old_fs); \
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ret; \
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})
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#endif /* __LINUX_UACCESS_H__ */
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