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author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-07-22 23:44:39 (GMT) |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-07-22 23:44:39 (GMT) |
commit | 4d4abdcb1dee03a4f9d6d2021622ed07e14dfd17 (patch) | |
tree | 4ed4c74b70240451065165fda5fb2059f8c6b1e5 /arch/x86/lib/usercopy.c | |
parent | 0342cbcfced2ee937d7c8e1c63f3d3082da7c7dc (diff) | |
parent | 7fcfd1abd6480d3b9ef17f5759c175e036e835cf (diff) | |
download | linux-fsl-qoriq-4d4abdcb1dee03a4f9d6d2021622ed07e14dfd17.tar.xz |
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (123 commits)
perf: Remove the nmi parameter from the oprofile_perf backend
x86, perf: Make copy_from_user_nmi() a library function
perf: Remove perf_event_attr::type check
x86, perf: P4 PMU - Fix typos in comments and style cleanup
perf tools: Make test use the preset debugfs path
perf tools: Add automated tests for events parsing
perf tools: De-opt the parse_events function
perf script: Fix display of IP address for non-callchain path
perf tools: Fix endian conversion reading event attr from file header
perf tools: Add missing 'node' alias to the hw_cache[] array
perf probe: Support adding probes on offline kernel modules
perf probe: Add probed module in front of function
perf probe: Introduce debuginfo to encapsulate dwarf information
perf-probe: Move dwarf library routines to dwarf-aux.{c, h}
perf probe: Remove redundant dwarf functions
perf probe: Move strtailcmp to string.c
perf probe: Rename DIE_FIND_CB_FOUND to DIE_FIND_CB_END
tracing/kprobe: Update symbol reference when loading module
tracing/kprobes: Support module init function probing
kprobes: Return -ENOENT if probe point doesn't exist
...
Diffstat (limited to 'arch/x86/lib/usercopy.c')
-rw-r--r-- | arch/x86/lib/usercopy.c | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/arch/x86/lib/usercopy.c b/arch/x86/lib/usercopy.c new file mode 100644 index 0000000..97be9cb --- /dev/null +++ b/arch/x86/lib/usercopy.c @@ -0,0 +1,43 @@ +/* + * User address space access functions. + * + * For licencing details see kernel-base/COPYING + */ + +#include <linux/highmem.h> +#include <linux/module.h> + +/* + * best effort, GUP based copy_from_user() that is NMI-safe + */ +unsigned long +copy_from_user_nmi(void *to, const void __user *from, unsigned long n) +{ + unsigned long offset, addr = (unsigned long)from; + unsigned long size, len = 0; + struct page *page; + void *map; + int ret; + + do { + ret = __get_user_pages_fast(addr, 1, 0, &page); + if (!ret) + break; + + offset = addr & (PAGE_SIZE - 1); + size = min(PAGE_SIZE - offset, n - len); + + map = kmap_atomic(page); + memcpy(to, map+offset, size); + kunmap_atomic(map); + put_page(page); + + len += size; + to += size; + addr += size; + + } while (len < n); + + return len; +} +EXPORT_SYMBOL_GPL(copy_from_user_nmi); |