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-rw-r--r--lib/maple_tree.c7
-rw-r--r--mm/huge_memory.c2
-rw-r--r--mm/madvise.c6
-rw-r--r--mm/shmem.c6
-rw-r--r--tools/testing/selftests/cachestat/test_cachestat.c80
5 files changed, 80 insertions, 21 deletions
diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index ffb9d15bd815..05d5db255c39 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -4107,6 +4107,10 @@ static inline unsigned char mas_wr_new_end(struct ma_wr_state *wr_mas)
* mas_wr_append: Attempt to append
* @wr_mas: the maple write state
*
+ * This is currently unsafe in rcu mode since the end of the node may be cached
+ * by readers while the node contents may be updated which could result in
+ * inaccurate information.
+ *
* Return: True if appended, false otherwise
*/
static inline bool mas_wr_append(struct ma_wr_state *wr_mas,
@@ -4116,6 +4120,9 @@ static inline bool mas_wr_append(struct ma_wr_state *wr_mas,
struct ma_state *mas = wr_mas->mas;
unsigned char node_pivots = mt_pivots[wr_mas->type];
+ if (mt_in_rcu(mas->tree))
+ return false;
+
if (mas->offset != wr_mas->node_end)
return false;
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 213bb1e33830..cb4432792b88 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1607,7 +1607,7 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
* If other processes are mapping this folio, we couldn't discard
* the folio unless they all do MADV_FREE so let's skip the folio.
*/
- if (folio_mapcount(folio) != 1)
+ if (folio_estimated_sharers(folio) != 1)
goto out;
if (!folio_trylock(folio))
diff --git a/mm/madvise.c b/mm/madvise.c
index 1fb2a11d77d9..b1f53a95e3a5 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -383,7 +383,7 @@ static int madvise_cold_or_pageout_pte_range(pmd_t *pmd,
folio = pfn_folio(pmd_pfn(orig_pmd));
/* Do not interfere with other mappings of this folio */
- if (folio_mapcount(folio) != 1)
+ if (folio_estimated_sharers(folio) != 1)
goto huge_unlock;
if (pageout_anon_only_filter && !folio_test_anon(folio))
@@ -459,7 +459,7 @@ regular_folio:
if (folio_test_large(folio)) {
int err;
- if (folio_mapcount(folio) != 1)
+ if (folio_estimated_sharers(folio) != 1)
break;
if (pageout_anon_only_filter && !folio_test_anon(folio))
break;
@@ -683,7 +683,7 @@ static int madvise_free_pte_range(pmd_t *pmd, unsigned long addr,
if (folio_test_large(folio)) {
int err;
- if (folio_mapcount(folio) != 1)
+ if (folio_estimated_sharers(folio) != 1)
break;
if (!folio_trylock(folio))
break;
diff --git a/mm/shmem.c b/mm/shmem.c
index 20daa207d8bf..99fb60ec2c3d 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -806,14 +806,16 @@ unsigned long shmem_partial_swap_usage(struct address_space *mapping,
XA_STATE(xas, &mapping->i_pages, start);
struct page *page;
unsigned long swapped = 0;
+ unsigned long max = end - 1;
rcu_read_lock();
- xas_for_each(&xas, page, end - 1) {
+ xas_for_each(&xas, page, max) {
if (xas_retry(&xas, page))
continue;
if (xa_is_value(page))
swapped++;
-
+ if (xas.xa_index == max)
+ break;
if (need_resched()) {
xas_pause(&xas);
cond_resched_rcu();
diff --git a/tools/testing/selftests/cachestat/test_cachestat.c b/tools/testing/selftests/cachestat/test_cachestat.c
index 54d09b820ed4..c037553cfd92 100644
--- a/tools/testing/selftests/cachestat/test_cachestat.c
+++ b/tools/testing/selftests/cachestat/test_cachestat.c
@@ -4,10 +4,12 @@
#include <stdio.h>
#include <stdbool.h>
#include <linux/kernel.h>
+#include <linux/magic.h>
#include <linux/mman.h>
#include <sys/mman.h>
#include <sys/shm.h>
#include <sys/syscall.h>
+#include <sys/vfs.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
@@ -15,6 +17,8 @@
#include "../kselftest.h"
+#define NR_TESTS 9
+
static const char * const dev_files[] = {
"/dev/zero", "/dev/null", "/dev/urandom",
"/proc/version", "/proc"
@@ -91,19 +95,33 @@ out:
}
/*
+ * fsync() is implemented via noop_fsync() on tmpfs. This makes the fsync()
+ * test fail below, so we need to check for test file living on a tmpfs.
+ */
+static bool is_on_tmpfs(int fd)
+{
+ struct statfs statfs_buf;
+
+ if (fstatfs(fd, &statfs_buf))
+ return false;
+
+ return statfs_buf.f_type == TMPFS_MAGIC;
+}
+
+/*
* Open/create the file at filename, (optionally) write random data to it
* (exactly num_pages), then test the cachestat syscall on this file.
*
* If test_fsync == true, fsync the file, then check the number of dirty
* pages.
*/
-bool test_cachestat(const char *filename, bool write_random, bool create,
- bool test_fsync, unsigned long num_pages, int open_flags,
- mode_t open_mode)
+static int test_cachestat(const char *filename, bool write_random, bool create,
+ bool test_fsync, unsigned long num_pages,
+ int open_flags, mode_t open_mode)
{
size_t PS = sysconf(_SC_PAGESIZE);
int filesize = num_pages * PS;
- bool ret = true;
+ int ret = KSFT_PASS;
long syscall_ret;
struct cachestat cs;
struct cachestat_range cs_range = { 0, filesize };
@@ -112,7 +130,7 @@ bool test_cachestat(const char *filename, bool write_random, bool create,
if (fd == -1) {
ksft_print_msg("Unable to create/open file.\n");
- ret = false;
+ ret = KSFT_FAIL;
goto out;
} else {
ksft_print_msg("Create/open %s\n", filename);
@@ -121,7 +139,7 @@ bool test_cachestat(const char *filename, bool write_random, bool create,
if (write_random) {
if (!write_exactly(fd, filesize)) {
ksft_print_msg("Unable to access urandom.\n");
- ret = false;
+ ret = KSFT_FAIL;
goto out1;
}
}
@@ -132,7 +150,7 @@ bool test_cachestat(const char *filename, bool write_random, bool create,
if (syscall_ret) {
ksft_print_msg("Cachestat returned non-zero.\n");
- ret = false;
+ ret = KSFT_FAIL;
goto out1;
} else {
@@ -142,15 +160,17 @@ bool test_cachestat(const char *filename, bool write_random, bool create,
if (cs.nr_cache + cs.nr_evicted != num_pages) {
ksft_print_msg(
"Total number of cached and evicted pages is off.\n");
- ret = false;
+ ret = KSFT_FAIL;
}
}
}
if (test_fsync) {
- if (fsync(fd)) {
+ if (is_on_tmpfs(fd)) {
+ ret = KSFT_SKIP;
+ } else if (fsync(fd)) {
ksft_print_msg("fsync fails.\n");
- ret = false;
+ ret = KSFT_FAIL;
} else {
syscall_ret = syscall(cachestat_nr, fd, &cs_range, &cs, 0);
@@ -161,13 +181,13 @@ bool test_cachestat(const char *filename, bool write_random, bool create,
print_cachestat(&cs);
if (cs.nr_dirty) {
- ret = false;
+ ret = KSFT_FAIL;
ksft_print_msg(
"Number of dirty should be zero after fsync.\n");
}
} else {
ksft_print_msg("Cachestat (after fsync) returned non-zero.\n");
- ret = false;
+ ret = KSFT_FAIL;
goto out1;
}
}
@@ -236,13 +256,29 @@ out:
int main(void)
{
- int ret = 0;
+ int ret;
+
+ ksft_print_header();
+
+ ret = syscall(__NR_cachestat, -1, NULL, NULL, 0);
+ if (ret == -1 && errno == ENOSYS)
+ ksft_exit_skip("cachestat syscall not available\n");
+
+ ksft_set_plan(NR_TESTS);
+
+ if (ret == -1 && errno == EBADF) {
+ ksft_test_result_pass("bad file descriptor recognized\n");
+ ret = 0;
+ } else {
+ ksft_test_result_fail("bad file descriptor ignored\n");
+ ret = 1;
+ }
for (int i = 0; i < 5; i++) {
const char *dev_filename = dev_files[i];
if (test_cachestat(dev_filename, false, false, false,
- 4, O_RDONLY, 0400))
+ 4, O_RDONLY, 0400) == KSFT_PASS)
ksft_test_result_pass("cachestat works with %s\n", dev_filename);
else {
ksft_test_result_fail("cachestat fails with %s\n", dev_filename);
@@ -251,13 +287,27 @@ int main(void)
}
if (test_cachestat("tmpfilecachestat", true, true,
- true, 4, O_CREAT | O_RDWR, 0400 | 0600))
+ false, 4, O_CREAT | O_RDWR, 0600) == KSFT_PASS)
ksft_test_result_pass("cachestat works with a normal file\n");
else {
ksft_test_result_fail("cachestat fails with normal file\n");
ret = 1;
}
+ switch (test_cachestat("tmpfilecachestat", true, true,
+ true, 4, O_CREAT | O_RDWR, 0600)) {
+ case KSFT_FAIL:
+ ksft_test_result_fail("cachestat fsync fails with normal file\n");
+ ret = KSFT_FAIL;
+ break;
+ case KSFT_PASS:
+ ksft_test_result_pass("cachestat fsync works with a normal file\n");
+ break;
+ case KSFT_SKIP:
+ ksft_test_result_skip("tmpfilecachestat is on tmpfs\n");
+ break;
+ }
+
if (test_cachestat_shmem())
ksft_test_result_pass("cachestat works with a shmem file\n");
else {