@@ -14,6 +14,7 @@
#include <sys/types.h>
#include <sys/syscall.h>
#include <sys/mman.h>
+#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/time.h>
@@ -34,8 +35,14 @@ static const char meminfo_fname[] = "/proc/meminfo";
static size_t testfile_size = 64 * 1024 * 1024;
static char *opt_fsizestr;
static int pagesize;
+static unsigned long cached_max;
+static int ovl_mounted;
#define MNTPOINT "mntpoint"
+#define OVL_LOWER MNTPOINT"/lower"
+#define OVL_UPPER MNTPOINT"/upper"
+#define OVL_WORK MNTPOINT"/work"
+#define OVL_MNT MNTPOINT"/ovl"
#define MIN_SANE_READAHEAD (4u * 1024u)
static const char mntpoint[] = MNTPOINT;
@@ -45,16 +52,28 @@ static struct tst_option options[] = {
{NULL, NULL, NULL}
};
-static int check_ret(void)
+static struct tcase {
+ const char *tname;
+ int use_overlay;
+} tcases[] = {
+ { "readahead on file", 0 },
+ { "readahead on overlayfs file", 1 },
+};
+
+static int readahead_supported = 1;
+
+static int check_ret(struct tcase *tc)
{
if (TST_RET == 0)
return 0;
- if (TST_ERR == EINVAL) {
+ if (TST_ERR == EINVAL &&
+ (!tc->use_overlay || !readahead_supported)) {
+ readahead_supported = 0;
tst_res(TCONF, "readahead not supported on %s",
tst_device->fs_type);
} else {
tst_res(TFAIL | TTERRNO, "readahead failed on %s",
- tst_device->fs_type);
+ tc->use_overlay ? "overlayfs" : tst_device->fs_type);
}
return 1;
}
@@ -112,12 +131,13 @@ static unsigned long get_cached_size(void)
return parse_entry(meminfo_fname, entry);
}
-static void create_testfile(void)
+static void create_testfile(int use_overlay)
{
int fd;
char *tmp;
size_t i;
+ sprintf(testfile, "%s/testfile", use_overlay ? OVL_MNT : MNTPOINT);
tst_res(TINFO, "creating test file of size: %zu", testfile_size);
tmp = SAFE_MALLOC(pagesize);
@@ -224,21 +244,33 @@ static void read_testfile(int do_readahead, const char *fname, size_t fsize,
SAFE_CLOSE(fd);
}
-static void test_readahead(void)
+static void test_readahead(unsigned int n)
{
unsigned long read_bytes, read_bytes_ra;
long usec, usec_ra;
- unsigned long cached_max, cached_low, cached, cached_ra;
+ unsigned long cached_high, cached_low, cached, cached_ra;
char proc_io_fname[128];
+ struct tcase *tc = &tcases[n];
+
+ tst_res(TINFO, "Test #%d: %s", n, tc->tname);
+
sprintf(proc_io_fname, "/proc/%u/io", getpid());
+ if (tc->use_overlay && !ovl_mounted) {
+ tst_res(TCONF,
+ "overlayfs is not configured in this kernel.");
+ return;
+ }
+
+ create_testfile(tc->use_overlay);
+
/* find out how much can cache hold if we read whole file */
read_testfile(0, testfile, testfile_size, &read_bytes, &usec, &cached);
- cached_max = get_cached_size();
+ cached_high = get_cached_size();
sync();
drop_caches();
cached_low = get_cached_size();
- cached_max = cached_max - cached_low;
+ cached_max = MAX(cached_max, cached_high - cached_low);
tst_res(TINFO, "read_testfile(0)");
read_testfile(0, testfile, testfile_size, &read_bytes, &usec, &cached);
@@ -253,7 +285,7 @@ static void test_readahead(void)
tst_res(TINFO, "read_testfile(1)");
read_testfile(1, testfile, testfile_size, &read_bytes_ra,
&usec_ra, &cached_ra);
- if (check_ret())
+ if (check_ret(tc))
return;
if (cached_ra > cached_low)
cached_ra = cached_ra - cached_low;
@@ -295,6 +327,28 @@ static void test_readahead(void)
}
}
+static void setup_overlay(void)
+{
+ int ret;
+
+ /* Setup an overlay mount with lower dir and file */
+ SAFE_MKDIR(OVL_LOWER, 0755);
+ SAFE_MKDIR(OVL_UPPER, 0755);
+ SAFE_MKDIR(OVL_WORK, 0755);
+ SAFE_MKDIR(OVL_MNT, 0755);
+ ret = mount("overlay", OVL_MNT, "overlay", 0, "lowerdir="OVL_LOWER
+ ",upperdir="OVL_UPPER",workdir="OVL_WORK);
+ if (ret < 0) {
+ if (errno == ENODEV) {
+ tst_res(TINFO,
+ "overlayfs is not configured in this kernel.");
+ return;
+ }
+ tst_brk(TBROK | TERRNO, "overlayfs mount failed");
+ }
+ ovl_mounted = 1;
+}
+
static void setup(void)
{
if (opt_fsizestr)
@@ -308,8 +362,13 @@ static void setup(void)
pagesize = getpagesize();
- sprintf(testfile, "%s/testfile", mntpoint);
- create_testfile();
+ setup_overlay();
+}
+
+static void cleanup(void)
+{
+ if (ovl_mounted)
+ SAFE_UMOUNT(OVL_MNT);
}
static struct tst_test test = {
@@ -318,8 +377,10 @@ static struct tst_test test = {
.mount_device = 1,
.mntpoint = mntpoint,
.setup = setup,
+ .cleanup = cleanup,
.options = options,
- .test_all = test_readahead,
+ .test = test_readahead,
+ .tcnt = ARRAY_SIZE(tcases),
};
#else /* __NR_readahead */
Repeat the test case on an overlayfs file. The new test case is a regression test for kernel commit b833a3660394 ("ovl: add ovl_fadvise()") which fixes a regression of readahead() on an overlay file that was introduced by kernel commit 5b910bd615ba ("ovl: fix GPF in swapfile_activate of file from overlayfs over xfs"). Signed-off-by: Amir Goldstein <amir73il@gmail.com> --- .../kernel/syscalls/readahead/readahead02.c | 85 ++++++++++++++++--- 1 file changed, 73 insertions(+), 12 deletions(-)