The patch titled
Subject: selftests/mm: check that PAGEMAP_SCAN returns correct categories
has been added to the -mm mm-unstable branch. Its filename is
selftests-mm-check-that-pagemap_scan-returns-correct-categories.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-mm-check-that-pagemap_scan-returns-correct-categories.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Andrei Vagin <avagin@xxxxxxxxxx>
Subject: selftests/mm: check that PAGEMAP_SCAN returns correct categories
Date: Mon, 6 Nov 2023 14:09:59 -0800
Right now, tests read page flags from /proc/pid/pagemap files. With this
change, tests will check that PAGEMAP_SCAN return correct information too.
Link: https://lkml.kernel.org/r/20231106220959.296568-2-avagin@xxxxxxxxxx
Signed-off-by: Andrei Vagin <avagin@xxxxxxxxxx>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx>
Tested-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx>
Cc: MichaÅ? MirosÅ?aw <mirq-linux@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/mm/vm_util.c | 53 +++++++++++++++++++++++--
1 file changed, 50 insertions(+), 3 deletions(-)
--- a/tools/testing/selftests/mm/vm_util.c~selftests-mm-check-that-pagemap_scan-returns-correct-categories
+++ a/tools/testing/selftests/mm/vm_util.c
@@ -4,6 +4,7 @@
#include <dirent.h>
#include <sys/ioctl.h>
#include <linux/userfaultfd.h>
+#include <linux/fs.h>
#include <sys/syscall.h>
#include <unistd.h>
#include "../kselftest.h"
@@ -28,19 +29,65 @@ uint64_t pagemap_get_entry(int fd, char
return entry;
}
+static uint64_t pagemap_scan_get_categories(int fd, char *start)
+{
+ struct pm_scan_arg arg;
+ struct page_region r;
+ long ret;
+
+ arg.start = (uintptr_t)start;
+ arg.end = (uintptr_t)(start + psize());
+ arg.vec = (uintptr_t)&r;
+ arg.vec_len = 1;
+ arg.flags = 0;
+ arg.size = sizeof(struct pm_scan_arg);
+ arg.max_pages = 0;
+ arg.category_inverted = 0;
+ arg.category_mask = 0;
+ arg.category_anyof_mask = PAGE_IS_WPALLOWED | PAGE_IS_WRITTEN | PAGE_IS_FILE |
+ PAGE_IS_PRESENT | PAGE_IS_SWAPPED | PAGE_IS_PFNZERO |
+ PAGE_IS_HUGE | PAGE_IS_SOFT_DIRTY;
+ arg.return_mask = arg.category_anyof_mask;
+
+ ret = ioctl(fd, PAGEMAP_SCAN, &arg);
+ if (ret < 0)
+ ksft_exit_fail_msg("PAGEMAP_SCAN failed: %s\n", strerror(errno));
+ if (ret == 0)
+ return 0;
+ return r.categories;
+}
+
+static bool page_entry_is(int fd, char *start, char *desc,
+ uint64_t pagemap_flags, uint64_t pagescan_flags)
+{
+ bool m, s;
+
+ m = pagemap_get_entry(fd, start) & pagemap_flags;
+ s = pagemap_scan_get_categories(fd, start) & pagescan_flags;
+ if (m == s)
+ return m;
+
+ ksft_exit_fail_msg(
+ "read and ioctl return unmatched results for %s: %d %d", desc, m, s);
+ return m;
+}
+
bool pagemap_is_softdirty(int fd, char *start)
{
- return pagemap_get_entry(fd, start) & PM_SOFT_DIRTY;
+ return page_entry_is(fd, start, "soft-dirty",
+ PM_SOFT_DIRTY, PAGE_IS_SOFT_DIRTY);
}
bool pagemap_is_swapped(int fd, char *start)
{
- return pagemap_get_entry(fd, start) & PM_SWAP;
+ return page_entry_is(fd, start, "swap", PM_SWAP, PAGE_IS_SWAPPED);
}
bool pagemap_is_populated(int fd, char *start)
{
- return pagemap_get_entry(fd, start) & (PM_PRESENT | PM_SWAP);
+ return page_entry_is(fd, start, "populated",
+ PM_PRESENT | PM_SWAP,
+ PAGE_IS_PRESENT | PAGE_IS_SWAPPED);
}
unsigned long pagemap_get_pfn(int fd, char *start)
_
Patches currently in -mm which might be from avagin@xxxxxxxxxx are
fs-proc-task_mmu-report-soft_dirty-bits-through-the-pagemap_scan-ioctl.patch
selftests-mm-check-that-pagemap_scan-returns-correct-categories.patch
