selftests/mm: drop global mem_fd in uffd tests

Drop it by creating the memfd dynamically in the tests.

Link: https://lkml.kernel.org/r/20230412164331.328584-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
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: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/tools/testing/selftests/mm/uffd-common.c b/tools/testing/selftests/mm/uffd-common.c
index 09ea24c5f02c0005ab7a73252b2a8b8371e998de..b1617f5d451794c14145b2ab8352f9910ec64c74 100644 (file)
--- a/tools/testing/selftests/mm/uffd-common.c
+++ b/tools/testing/selftests/mm/uffd-common.c
@@ -12,12 +12,32 @@
 volatile bool test_uffdio_copy_eexist = true;
 unsigned long nr_cpus, nr_pages, nr_pages_per_cpu, page_size, hpage_size;
 char *area_src, *area_src_alias, *area_dst, *area_dst_alias, *area_remap;
-int mem_fd, uffd = -1, uffd_flags, finished, *pipefd, test_type;
+int uffd = -1, uffd_flags, finished, *pipefd, test_type;
 bool map_shared, test_collapse, test_dev_userfaultfd;
 bool test_uffdio_wp = true, test_uffdio_minor = false;
 unsigned long long *count_verify;
 uffd_test_ops_t *uffd_test_ops;
 
+static int uffd_mem_fd_create(off_t mem_size, bool hugetlb)
+{
+       unsigned int memfd_flags = 0;
+       int mem_fd;
+
+       if (hugetlb)
+               memfd_flags = MFD_HUGETLB;
+       mem_fd = memfd_create("uffd-test", memfd_flags);
+       if (mem_fd < 0)
+               err("memfd_create");
+       if (ftruncate(mem_fd, mem_size))
+               err("ftruncate");
+       if (fallocate(mem_fd,
+                     FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 0,
+                     mem_size))
+               err("fallocate");
+
+       return mem_fd;
+}
+
 static void anon_release_pages(char *rel_area)
 {
        if (madvise(rel_area, nr_pages * page_size, MADV_DONTNEED))
@@ -51,6 +71,7 @@ static void hugetlb_allocate_area(void **alloc_area, bool is_src)
        off_t offset = is_src ? 0 : size;
        void *area_alias = NULL;
        char **alloc_area_alias;
+       int mem_fd = uffd_mem_fd_create(size * 2, true);
 
        *alloc_area = mmap(NULL, size, PROT_READ | PROT_WRITE,
                           (map_shared ? MAP_SHARED : MAP_PRIVATE) |
@@ -73,6 +94,8 @@ static void hugetlb_allocate_area(void **alloc_area, bool is_src)
        }
        if (area_alias)
                *alloc_area_alias = area_alias;
+
+       close(mem_fd);
 }
 
 static void hugetlb_alias_mapping(__u64 *start, size_t len, unsigned long offset)
@@ -95,6 +118,7 @@ static void shmem_allocate_area(void **alloc_area, bool is_src)
        size_t bytes = nr_pages * page_size;
        unsigned long offset = is_src ? 0 : bytes;
        char *p = NULL, *p_alias = NULL;
+       int mem_fd = uffd_mem_fd_create(bytes * 2, false);
 
        if (test_collapse) {
                p = BASE_PMD_ADDR;
@@ -124,6 +148,8 @@ static void shmem_allocate_area(void **alloc_area, bool is_src)
                area_src_alias = area_alias;
        else
                area_dst_alias = area_alias;
+
+       close(mem_fd);
 }
 
 static void shmem_alias_mapping(__u64 *start, size_t len, unsigned long offset)

diff --git a/tools/testing/selftests/mm/uffd-common.h b/tools/testing/selftests/mm/uffd-common.h
index 11f770391bd9114ea8f446b5653352dc41525bcb..0dfab7057295608cbe298ec6d3f7e48ad0a896b1 100644 (file)
--- a/tools/testing/selftests/mm/uffd-common.h
+++ b/tools/testing/selftests/mm/uffd-common.h
@@ -87,7 +87,7 @@ typedef struct uffd_test_ops uffd_test_ops_t;
 
 extern unsigned long nr_cpus, nr_pages, nr_pages_per_cpu, page_size, hpage_size;
 extern char *area_src, *area_src_alias, *area_dst, *area_dst_alias, *area_remap;
-extern int mem_fd, uffd, uffd_flags, finished, *pipefd, test_type;
+extern int uffd, uffd_flags, finished, *pipefd, test_type;
 extern bool map_shared, test_collapse, test_dev_userfaultfd;
 extern bool test_uffdio_wp, test_uffdio_minor;
 extern unsigned long long *count_verify;

diff --git a/tools/testing/selftests/mm/uffd-stress.c b/tools/testing/selftests/mm/uffd-stress.c
index e6d39a7550822605d8fd22bb4085a1f29b1a83ad..4eca1a0276c2ec7d3b549c83e79bbc5772703f61 100644 (file)
--- a/tools/testing/selftests/mm/uffd-stress.c
+++ b/tools/testing/selftests/mm/uffd-stress.c
@@ -1090,21 +1090,6 @@ int main(int argc, char **argv)
        }
        nr_pages = nr_pages_per_cpu * nr_cpus;
 
-       if (test_type == TEST_SHMEM || test_type == TEST_HUGETLB) {
-               unsigned int memfd_flags = 0;
-
-               if (test_type == TEST_HUGETLB)
-                       memfd_flags = MFD_HUGETLB;
-               mem_fd = memfd_create(argv[0], memfd_flags);
-               if (mem_fd < 0)
-                       err("memfd_create");
-               if (ftruncate(mem_fd, nr_pages * page_size * 2))
-                       err("ftruncate");
-               if (fallocate(mem_fd,
-                             FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 0,
-                             nr_pages * page_size * 2))
-                       err("fallocate");
-       }
        printf("nr_pages: %lu, nr_pages_per_cpu: %lu\n",
               nr_pages, nr_pages_per_cpu);
        return userfaultfd_stress();