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selftests/mm: let uffd_handle_page_fault() take wp parameter

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Make the handler optionally apply WP bit when resolving page faults for
either missing or minor page faults.  This moves towards removing global
test_uffdio_wp outside of the common code.

Link: https://lkml.kernel.org/r/20230412164341.328618-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Peter Xu 2023-04-12 12:43:41 -04:00 committed by Andrew Morton
parent 508340845d
commit 0210c43ef6
3 changed files with 23 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
tools/testing/selftests/mm/uffd-common.c
View File

@ -353,7 +353,7 @@ void wp_range(int ufd, __u64 start, __u64 len, bool wp)
err("clear WP failed: address=0x%"PRIx64, (uint64_t)start);
}
static void continue_range(int ufd, __u64 start, __u64 len)
static void continue_range(int ufd, __u64 start, __u64 len, bool wp)
{
struct uffdio_continue req;
int ret;
@ -361,7 +361,7 @@ static void continue_range(int ufd, __u64 start, __u64 len)
req.range.start = start;
req.range.len = len;
req.mode = 0;
if (test_uffdio_wp)
if (wp)
req.mode |= UFFDIO_CONTINUE_MODE_WP;
if (ioctl(ufd, UFFDIO_CONTINUE, &req))
@ -429,7 +429,8 @@ void uffd_handle_page_fault(struct uffd_msg *msg, struct uffd_args *args)
area_dst_alias));
for (b = 0; b < page_size; ++b)
area[b] = ~area[b];
continue_range(uffd, msg->arg.pagefault.address, page_size);
continue_range(uffd, msg->arg.pagefault.address, page_size,
args->apply_wp);
args->minor_faults++;
} else {
/*
@ -459,7 +460,7 @@ void uffd_handle_page_fault(struct uffd_msg *msg, struct uffd_args *args)
offset = (char *)(unsigned long)msg->arg.pagefault.address - area_dst;
offset &= ~(page_size-1);
if (copy_page(uffd, offset))
if (copy_page(uffd, offset, args->apply_wp))
args->missing_faults++;
}
}
@ -555,7 +556,7 @@ static void wake_range(int ufd, unsigned long addr, unsigned long len)
addr), exit(1);
}
int __copy_page(int ufd, unsigned long offset, bool retry)
int __copy_page(int ufd, unsigned long offset, bool retry, bool wp)
{
struct uffdio_copy uffdio_copy;
@ -564,7 +565,7 @@ int __copy_page(int ufd, unsigned long offset, bool retry)
uffdio_copy.dst = (unsigned long) area_dst + offset;
uffdio_copy.src = (unsigned long) area_src + offset;
uffdio_copy.len = page_size;
if (test_uffdio_wp)
if (wp)
uffdio_copy.mode = UFFDIO_COPY_MODE_WP;
else
uffdio_copy.mode = 0;
@ -587,7 +588,7 @@ int __copy_page(int ufd, unsigned long offset, bool retry)
return 0;
}
int copy_page(int ufd, unsigned long offset)
int copy_page(int ufd, unsigned long offset, bool wp)
{
return __copy_page(ufd, offset, false);
return __copy_page(ufd, offset, false, wp);
}

6
tools/testing/selftests/mm/uffd-common.h
View File

@ -72,6 +72,8 @@
/* Userfaultfd test statistics */
struct uffd_args {
int cpu;
/* Whether apply wr-protects when installing pages */
bool apply_wp;
unsigned long missing_faults;
unsigned long wp_faults;
unsigned long minor_faults;
@ -104,8 +106,8 @@ void userfaultfd_open(uint64_t *features);
int uffd_read_msg(int ufd, struct uffd_msg *msg);
void wp_range(int ufd, __u64 start, __u64 len, bool wp);
void uffd_handle_page_fault(struct uffd_msg *msg, struct uffd_args *args);
int __copy_page(int ufd, unsigned long offset, bool retry);
int copy_page(int ufd, unsigned long offset);
int __copy_page(int ufd, unsigned long offset, bool retry, bool wp);
int copy_page(int ufd, unsigned long offset, bool wp);
void *uffd_poll_thread(void *arg);
#define TEST_ANON 1

16
tools/testing/selftests/mm/uffd-stress.c
View File

@ -96,6 +96,7 @@ static void uffd_stats_reset(struct uffd_args *args, unsigned long n_cpus)
for (i = 0; i < n_cpus; i++) {
args[i].cpu = i;
args[i].apply_wp = test_uffdio_wp;
args[i].missing_faults = 0;
args[i].wp_faults = 0;
args[i].minor_faults = 0;
@ -155,7 +156,7 @@ static void *locking_thread(void *arg)
static int copy_page_retry(int ufd, unsigned long offset)
{
return __copy_page(ufd, offset, true);
return __copy_page(ufd, offset, true, test_uffdio_wp);
}
pthread_mutex_t uffd_read_mutex = PTHREAD_MUTEX_INITIALIZER;
@ -308,7 +309,7 @@ static void sighndl(int sig, siginfo_t *siginfo, void *ptr)
* This also tests UFFD_FEATURE_EVENT_FORK event along with the signal
* feature. Using monitor thread, verify no userfault events are generated.
*/
static int faulting_process(int signal_test)
static int faulting_process(int signal_test, bool wp)
{
unsigned long nr;
unsigned long long count;
@ -343,7 +344,7 @@ static int faulting_process(int signal_test)
if (steps == 1) {
/* This is a MISSING request */
steps++;
if (copy_page(uffd, offset))
if (copy_page(uffd, offset, wp))
signalled++;
} else {
/* This is a WP request */
@ -507,6 +508,7 @@ static int userfaultfd_events_test(void)
true, test_uffdio_wp, false))
err("register failure");
args.apply_wp = test_uffdio_wp;
if (pthread_create(&uffd_mon, &attr, uffd_poll_thread, &args))
err("uffd_poll_thread create");
@ -515,7 +517,7 @@ static int userfaultfd_events_test(void)
err("fork");
if (!pid)
exit(faulting_process(0));
exit(faulting_process(0, test_uffdio_wp));
waitpid(pid, &err, 0);
if (err)
@ -551,11 +553,12 @@ static int userfaultfd_sig_test(void)
true, test_uffdio_wp, false))
err("register failure");
if (faulting_process(1))
if (faulting_process(1, test_uffdio_wp))
err("faulting process failed");
uffd_test_ops->release_pages(area_dst);
args.apply_wp = test_uffdio_wp;
if (pthread_create(&uffd_mon, &attr, uffd_poll_thread, &args))
err("uffd_poll_thread create");
@ -564,7 +567,7 @@ static int userfaultfd_sig_test(void)
err("fork");
if (!pid)
exit(faulting_process(2));
exit(faulting_process(2, test_uffdio_wp));
waitpid(pid, &err, 0);
if (err)
@ -628,6 +631,7 @@ static int userfaultfd_minor_test(void)
page_size);
}
args.apply_wp = test_uffdio_wp;
if (pthread_create(&uffd_mon, &attr, uffd_poll_thread, &args))
err("uffd_poll_thread create");