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| author | Petr Mladek <pmladek@suse.com> | 2021-11-02 10:39:27 +0100 |
|---|---|---|
| committer | Petr Mladek <pmladek@suse.com> | 2021-11-02 10:39:27 +0100 |
| commit | 40e64a88dadcfa168914065baf7f035de957bbe0 (patch) | |
| tree | 06c8c4a9e6c1b478aa6851794c6a33bec1ce6ec4 /mm/maccess.c | |
| parent | 24a1dffbecafeb00d8830985eb7a318e37aabc4e (diff) | |
| parent | 6a7ca80f4033c9cf3003625b2ef8b497f4ec44da (diff) | |
| download | linux-40e64a88dadcfa168914065baf7f035de957bbe0.tar.gz linux-40e64a88dadcfa168914065baf7f035de957bbe0.tar.bz2 linux-40e64a88dadcfa168914065baf7f035de957bbe0.zip | |
Merge branch 'for-5.16-vsprintf-pgp' into for-linus
Diffstat (limited to 'mm/maccess.c')
| -rw-r--r-- | mm/maccess.c | 28 |
1 files changed, 22 insertions, 6 deletions
diff --git a/mm/maccess.c b/mm/maccess.c index 3bd70405f2d8..d3f1a1f0b1c1 100644 --- a/mm/maccess.c +++ b/mm/maccess.c @@ -24,13 +24,21 @@ bool __weak copy_from_kernel_nofault_allowed(const void *unsafe_src, long copy_from_kernel_nofault(void *dst, const void *src, size_t size) { + unsigned long align = 0; + + if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) + align = (unsigned long)dst | (unsigned long)src; + if (!copy_from_kernel_nofault_allowed(src, size)) return -ERANGE; pagefault_disable(); - copy_from_kernel_nofault_loop(dst, src, size, u64, Efault); - copy_from_kernel_nofault_loop(dst, src, size, u32, Efault); - copy_from_kernel_nofault_loop(dst, src, size, u16, Efault); + if (!(align & 7)) + copy_from_kernel_nofault_loop(dst, src, size, u64, Efault); + if (!(align & 3)) + copy_from_kernel_nofault_loop(dst, src, size, u32, Efault); + if (!(align & 1)) + copy_from_kernel_nofault_loop(dst, src, size, u16, Efault); copy_from_kernel_nofault_loop(dst, src, size, u8, Efault); pagefault_enable(); return 0; @@ -50,10 +58,18 @@ EXPORT_SYMBOL_GPL(copy_from_kernel_nofault); long copy_to_kernel_nofault(void *dst, const void *src, size_t size) { + unsigned long align = 0; + + if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) + align = (unsigned long)dst | (unsigned long)src; + pagefault_disable(); - copy_to_kernel_nofault_loop(dst, src, size, u64, Efault); - copy_to_kernel_nofault_loop(dst, src, size, u32, Efault); - copy_to_kernel_nofault_loop(dst, src, size, u16, Efault); + if (!(align & 7)) + copy_to_kernel_nofault_loop(dst, src, size, u64, Efault); + if (!(align & 3)) + copy_to_kernel_nofault_loop(dst, src, size, u32, Efault); + if (!(align & 1)) + copy_to_kernel_nofault_loop(dst, src, size, u16, Efault); copy_to_kernel_nofault_loop(dst, src, size, u8, Efault); pagefault_enable(); return 0; |