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author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-09 09:11:21 +0200 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-09 09:11:21 +0200 |
commit | 0154ec71d597692a0d0682b19eac4b3adfb7f3dc (patch) | |
tree | 121b4ac35146f5696da090d3ae2534c76523e6c2 /mm/gup.c | |
parent | VMCI: Fixup atomic64_t abuse (diff) | |
parent | Linux 5.2-rc4 (diff) | |
download | linux-dev-0154ec71d597692a0d0682b19eac4b3adfb7f3dc.tar.xz linux-dev-0154ec71d597692a0d0682b19eac4b3adfb7f3dc.zip |
Merge 5.2-rc4 into char-misc-next
We want the char/misc driver fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'mm/gup.c')
-rw-r--r-- | mm/gup.c | 16 |
1 files changed, 9 insertions, 7 deletions
@@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only #include <linux/kernel.h> #include <linux/errno.h> #include <linux/err.h> @@ -1041,10 +1042,6 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk, BUG_ON(ret >= nr_pages); } - if (!pages) - /* If it's a prefault don't insist harder */ - return ret; - if (ret > 0) { nr_pages -= ret; pages_done += ret; @@ -1060,8 +1057,12 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk, pages_done = ret; break; } - /* VM_FAULT_RETRY triggered, so seek to the faulting offset */ - pages += ret; + /* + * VM_FAULT_RETRY triggered, so seek to the faulting offset. + * For the prefault case (!pages) we only update counts. + */ + if (likely(pages)) + pages += ret; start += ret << PAGE_SHIFT; /* @@ -1084,7 +1085,8 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk, pages_done++; if (!nr_pages) break; - pages++; + if (likely(pages)) + pages++; start += PAGE_SIZE; } if (lock_dropped && *locked) { |