On Tue, Nov 12, 2019 at 08:27:10PM -0800, John Hubbard wrote: > Now that all other kernel callers of get_user_pages(FOLL_LONGTERM) > have been converted to pin_longterm_pages(), lock it down: > > 1) Add an assertion to get_user_pages(), preventing callers from > passing FOLL_LONGTERM (in addition to the existing assertion that > prevents FOLL_PIN). > > 2) Remove the associated GUP_LONGTERM_BENCHMARK test. > > Signed-off-by: John Hubbard <jhubb...@nvidia.com> > --- > mm/gup.c | 8 ++++---- > mm/gup_benchmark.c | 9 +-------- > tools/testing/selftests/vm/gup_benchmark.c | 7 ++----- > 3 files changed, 7 insertions(+), 17 deletions(-) > > diff --git a/mm/gup.c b/mm/gup.c > index 82e7e4ce5027..90f5f95ee7ac 100644 > --- a/mm/gup.c > +++ b/mm/gup.c > @@ -1756,11 +1756,11 @@ long get_user_pages(unsigned long start, unsigned > long nr_pages, > struct vm_area_struct **vmas) > { > /* > - * FOLL_PIN must only be set internally by the pin_user_page*() and > - * pin_longterm_*() APIs, never directly by the caller, so enforce that > - * with an assertion: > + * FOLL_PIN and FOLL_LONGTERM must only be set internally by the > + * pin_user_page*() and pin_longterm_*() APIs, never directly by the > + * caller, so enforce that with an assertion: > */ > - if (WARN_ON_ONCE(gup_flags & FOLL_PIN)) > + if (WARN_ON_ONCE(gup_flags & (FOLL_PIN | FOLL_LONGTERM)))
Don't we want to block FOLL_LONGTERM in get_user_pages_fast() as well after all this? Ira > return -EINVAL; > > return __gup_longterm_locked(current, current->mm, start, nr_pages, > diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c > index 8f980d91dbf5..679f0e6a0adb 100644 > --- a/mm/gup_benchmark.c > +++ b/mm/gup_benchmark.c > @@ -6,7 +6,7 @@ > #include <linux/debugfs.h> > > #define GUP_FAST_BENCHMARK _IOWR('g', 1, struct gup_benchmark) > -#define GUP_LONGTERM_BENCHMARK _IOWR('g', 2, struct gup_benchmark) > +/* Command 2 has been deleted. */ > #define GUP_BENCHMARK _IOWR('g', 3, struct gup_benchmark) > #define PIN_FAST_BENCHMARK _IOWR('g', 4, struct gup_benchmark) > #define PIN_LONGTERM_BENCHMARK _IOWR('g', 5, struct gup_benchmark) > @@ -28,7 +28,6 @@ static void put_back_pages(int cmd, struct page **pages, > unsigned long nr_pages) > > switch (cmd) { > case GUP_FAST_BENCHMARK: > - case GUP_LONGTERM_BENCHMARK: > case GUP_BENCHMARK: > for (i = 0; i < nr_pages; i++) > put_page(pages[i]); > @@ -97,11 +96,6 @@ static int __gup_benchmark_ioctl(unsigned int cmd, > nr = get_user_pages_fast(addr, nr, gup->flags, > pages + i); > break; > - case GUP_LONGTERM_BENCHMARK: > - nr = get_user_pages(addr, nr, > - gup->flags | FOLL_LONGTERM, > - pages + i, NULL); > - break; > case GUP_BENCHMARK: > nr = get_user_pages(addr, nr, gup->flags, pages + i, > NULL); > @@ -159,7 +153,6 @@ static long gup_benchmark_ioctl(struct file *filep, > unsigned int cmd, > > switch (cmd) { > case GUP_FAST_BENCHMARK: > - case GUP_LONGTERM_BENCHMARK: > case GUP_BENCHMARK: > case PIN_FAST_BENCHMARK: > case PIN_LONGTERM_BENCHMARK: > diff --git a/tools/testing/selftests/vm/gup_benchmark.c > b/tools/testing/selftests/vm/gup_benchmark.c > index 03928e47a86f..836b7082db13 100644 > --- a/tools/testing/selftests/vm/gup_benchmark.c > +++ b/tools/testing/selftests/vm/gup_benchmark.c > @@ -15,7 +15,7 @@ > #define PAGE_SIZE sysconf(_SC_PAGESIZE) > > #define GUP_FAST_BENCHMARK _IOWR('g', 1, struct gup_benchmark) > -#define GUP_LONGTERM_BENCHMARK _IOWR('g', 2, struct gup_benchmark) > +/* Command 2 has been deleted. */ > #define GUP_BENCHMARK _IOWR('g', 3, struct gup_benchmark) > > /* > @@ -49,7 +49,7 @@ int main(int argc, char **argv) > char *file = "/dev/zero"; > char *p; > > - while ((opt = getopt(argc, argv, "m:r:n:f:abctTLUuwSH")) != -1) { > + while ((opt = getopt(argc, argv, "m:r:n:f:abctTUuwSH")) != -1) { > switch (opt) { > case 'a': > cmd = PIN_FAST_BENCHMARK; > @@ -75,9 +75,6 @@ int main(int argc, char **argv) > case 'T': > thp = 0; > break; > - case 'L': > - cmd = GUP_LONGTERM_BENCHMARK; > - break; > case 'U': > cmd = GUP_BENCHMARK; > break; > -- > 2.24.0 >