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overlay: getdents: support lseek

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Refs: #1421
Change-Id: Ife7ab1b50159a5897552ff695bb001ada27ec934
This commit is contained in:
Masamichi Takagi
2019-11-13 15:51:20 +09:00
parent 7fc4272b89
commit 3c256e1a6c
5 changed files with 667 additions and 75 deletions
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410
executer/user/mcexec.c
View File

@ -3003,12 +3003,16 @@ int close_cloexec_fds(int mcos_fd)
struct overlay_fd {
int fd; /* associated fd, points to mckernel side */
int getdents_fd; /* non-seekable mckernel fd */
int linux_fd; /* linux fd, -1 if not opened */
struct list_head link;
char path[PATH_MAX]; /* linux path */
char linux_path[PATH_MAX]; /* linux path */
char mck_path[PATH_MAX]; /* mckernel path */
size_t pathlen;
void *dirents; /* copy of mckernel dirents to filter duplicates */
size_t dirents_size;
void *mck_dirents; /* cache of mckernel dirents to filter duplicates */
size_t mck_dirents_size;
void *linux_dirents; /* cache of filtered Linux dirents */
size_t linux_dirents_size;
};
LIST_HEAD(overlay_fd_list);
@ -3039,10 +3043,15 @@ void overlay_addfd(int fd, const char *path)
}
ofd->fd = fd;
ofd->getdents_fd = -1;
ofd->linux_fd = -1;
ofd->dirents = NULL;
ofd->dirents_size = 0;
ofd->pathlen = snprintf(ofd->path, PATH_MAX, "%s%s", prefix, real_path);
ofd->mck_dirents = NULL;
ofd->mck_dirents_size = 0;
ofd->linux_dirents = NULL;
ofd->linux_dirents_size = 0;
ofd->pathlen = snprintf(ofd->linux_path, PATH_MAX, "%s%s",
prefix, real_path);
strncpy(ofd->mck_path, path, PATH_MAX);
pthread_spin_lock(&overlay_fd_lock);
list_add(&ofd->link, &overlay_fd_list);
@ -3057,9 +3066,12 @@ void overlay_delfd(int fd)
list_for_each_entry(ofd, &overlay_fd_list, link) {
if (ofd->fd == fd) {
list_del(&ofd->link);
if (ofd->getdents_fd != -1)
close(ofd->getdents_fd);
if (ofd->linux_fd != -1)
close(ofd->linux_fd);
free(ofd->dirents);
free(ofd->mck_dirents);
free(ofd->linux_dirents);
free(ofd);
break;
}
@ -3401,122 +3413,370 @@ static inline char *dirent_name(int sysnum, void *_dirp)
exit(-1);
}
static inline void *dirent_off(int sysnum, void *_dirp)
{
#ifdef __NR_getdents
if (sysnum == __NR_getdents) {
struct linux_dirent *dirp = _dirp;
return &(dirp->d_off);
}
#endif
if (sysnum == __NR_getdents64) {
struct linux_dirent64 *dirp = _dirp;
return &(dirp->d_off);
}
fprintf(stderr, "%s: unexpected syscall number %d\n",
__func__, sysnum);
exit(-1);
}
int copy_dirents(void *_dirp, void *dirents, size_t dirents_size,
off_t offset, unsigned int *count, int sysnum)
{
off_t max_len;
int len;
void *dirp_iter;
unsigned short reclen;
max_len = dirents_size - offset > *count ?
*count : dirents_size - offset;
__dprintf("max_len: %ld\n", max_len);
for (len = 0; len < max_len;) {
dirp_iter = dirents + offset + len;
reclen = dirent_reclen(sysnum, dirp_iter);
/* early exit on record boundary */
if (len + reclen > max_len) {
/* don't try to copy lower */
*count = 0;
__dprintf("early exit: len: %d, reclen: %d, max_len: %ld\n",
len, reclen, max_len);
goto out;
}
memcpy(_dirp + len, dirp_iter, reclen);
len += reclen;
}
*count -= len;
out:
return len;
}
int overlay_getdents(int sysnum, int fd, void *_dirp, unsigned int count)
{
void *dirp, *mcdirp;
int ret = 0, pos, linux_ret, mcpos;
void *dirp = NULL;
void *linux_dirp_iter, *mck_dirp_iter;
int ret, ret_before_edit;
int mck_ret = 0, pos;
int linux_ret = 0, mcpos;
unsigned short reclen;
struct overlay_fd *ofd = NULL, *ofd_iter;
int hide_orig = 0;
off_t offset;
char ofd_path[PATH_MAX];
int mck_len, linux_len;
pthread_spin_lock(&overlay_fd_lock);
list_for_each_entry(ofd_iter, &overlay_fd_list, link) {
if (ofd_iter->fd == fd) {
ofd = ofd_iter;
__dprintf("found overlay cache entry (%s)\n",
ofd->path);
ofd->linux_path);
break;
}
}
pthread_spin_unlock(&overlay_fd_lock);
/* special case for /proc/N/task */
if (ofd && !strncmp(ofd->path, "/proc", 5) &&
!strncmp(ofd->path + strlen(ofd->path) - 4,
"task", 4)) {
if (ofd && !strncmp(ofd->linux_path, "/proc", 5) &&
!strncmp(ofd->linux_path + strlen(ofd->linux_path) - 4,
"task", 4)) {
hide_orig = 1;
}
/* not a directory we overlay, or not there yet */
if (ofd == NULL || ofd->linux_fd == -1 || hide_orig) {
/* not a directory we overlay or hiding lower fs */
if (ofd == NULL || hide_orig) {
ret = syscall(sysnum, fd, _dirp, count);
if (ret == -1)
if (ret == -1) {
ret = -errno;
}
if (ofd == NULL || ret < 0 || hide_orig)
return ret;
/* copy mckernel dirents to our buffer, in case of split getdents */
if (ret > 0) {
void *newbuf = realloc(ofd->dirents, ofd->dirents_size + ret);
if (!newbuf) {
fprintf(stderr, "%s: not enough memory (%zd)",
__func__, ofd->dirents_size + ret);
return ret;
goto err;
}
ofd->dirents = newbuf;
memcpy(ofd->dirents + ofd->dirents_size, _dirp, ret);
ofd->dirents_size += ret;
goto out_mck_only;
}
/* return first directory result unless it is empty or there
* is obvious room for more elements.
* The second check could have false positives depending on
* the fs, but should not be for filesystems we overlay
*/
if (ret > 0 && count - ret < 500)
return ret;
dirp = malloc(count);
if (!dirp) {
fprintf(stderr, "%s: out of memory\n", __func__);
ret = -ENOMEM;
goto err;
}
if (ofd->linux_fd == -1) {
ofd->linux_fd = open(ofd->path, O_RDONLY|O_DIRECTORY);
if (ofd->linux_fd < 0) {
offset = lseek(fd, 0, SEEK_CUR);
if (offset == (off_t)-1) {
ret = -errno;
goto err;
}
__dprintf("offset: %ld\n", offset);
if (ofd->getdents_fd == -1) {
ofd->getdents_fd = open(ofd->mck_path, O_RDONLY | O_DIRECTORY);
if (ofd->getdents_fd < 0) {
ret = -errno;
if (errno != ENOENT) {
fprintf(stderr, "%s: could not open %s: %d\n",
__func__, ofd->path, errno);
__func__, ofd->mck_path, errno);
}
return ret;
goto err;
}
}
again:
linux_ret = syscall(sysnum, ofd->linux_fd, _dirp + ret, count - ret);
if (linux_ret < 0) {
mck_again:
/* Use "count" to simplify the handling of
* "Result buffer is too small" case
*/
ret = syscall(sysnum, ofd->getdents_fd, dirp, count);
if (ret < 0) {
ret = -errno;
goto err;
}
mck_ret += ret;
__dprintf("getdents from upper: mck_ret: %d, ret: %d, count: %d\n",
mck_ret, ret, count);
/* cache mckernel dirents to our buffer, in case of split getdents */
if (ret > 0) {
void *newbuf = realloc(ofd->mck_dirents,
ofd->mck_dirents_size + ret);
if (!newbuf) {
ret = -ENOMEM;
fprintf(stderr, "%s: not enough memory (%zd)",
__func__, ofd->mck_dirents_size + ret);
goto err;
}
ofd->mck_dirents = newbuf;
memcpy(ofd->mck_dirents + ofd->mck_dirents_size, dirp, ret);
/* Rewrite d_off to match the packed data layout.
* (EOF of fd) >= (EOF of upper + lower) is assumed.
* See generic_file_llseek_size().
*/
for (mcpos = ofd->mck_dirents_size;
mcpos < ofd->mck_dirents_size + ret;) {
mck_dirp_iter = ofd->mck_dirents + mcpos;
reclen = dirent_reclen(sysnum, mck_dirp_iter);
#ifdef DEBUG
printf("<%s,%d,%ld> ",
dirent_name(sysnum, mck_dirp_iter),
dirent_reclen(sysnum, mck_dirp_iter),
*((unsigned long *)
dirent_off(sysnum, mck_dirp_iter)));
#endif
*((unsigned long *)
dirent_off(sysnum, mck_dirp_iter)) = mcpos + reclen;
mcpos += reclen;
}
#ifdef DEBUG
printf("\n");
#endif
ofd->mck_dirents_size += ret;
}
/* Fill as many entries as possbile to avoid
* upper entries appear to be inserted in the
* following getdents
*/
if (ret > 0 && mck_ret < count) {
goto mck_again;
}
if (ofd->linux_fd == -1) {
ofd->linux_fd = open(ofd->linux_path, O_RDONLY | O_DIRECTORY);
if (ofd->linux_fd < 0) {
ret = -errno;
if (errno != ENOENT) {
fprintf(stderr, "%s: could not open %s: %d\n",
__func__, ofd->linux_path, errno);
}
goto err;
}
}
/* lower fs path for blacklist check */
strncpy(ofd_path, ofd->linux_path, PATH_MAX - ofd->pathlen);
linux_again:
/* greedy-fetch because the results would be blacklisted */
ret = syscall(sysnum, ofd->linux_fd, dirp, count);
if (ret < 0) {
ret = -errno;
fprintf(stderr, "%s: linux getdents failed: %d\n",
__func__, errno);
return ret;
goto err;
}
if (linux_ret == 0)
return ret;
ret_before_edit = ret;
for (pos = ret; pos < ret + linux_ret;) {
dirp = _dirp + pos;
reclen = dirent_reclen(sysnum, dirp);
snprintf(ofd->path + ofd->pathlen, PATH_MAX - ofd->pathlen,
"/%s", dirent_name(sysnum, dirp));
for (pos = 0; pos < ret;) {
linux_dirp_iter = dirp + pos;
reclen = dirent_reclen(sysnum, linux_dirp_iter);
snprintf(ofd_path + ofd->pathlen, PATH_MAX - ofd->pathlen,
"/%s", dirent_name(sysnum, linux_dirp_iter));
/* remove blacklist */
if (overlay_blacklist(ofd->path)) {
__dprintf("blacklisted %s\n", ofd->path);
memmove(_dirp + pos,
_dirp + pos + reclen,
ret + linux_ret - pos - reclen);
linux_ret -= reclen;
if (overlay_blacklist(ofd_path)) {
__dprintf("blacklisted: %s\n", ofd_path);
memmove(dirp + pos,
dirp + pos + reclen,
ret - pos - reclen);
ret -= reclen;
continue;
}
/* remove duplicates */
for (mcpos = 0; mcpos < ofd->dirents_size;) {
mcdirp = ofd->dirents + mcpos;
if (!strcmp(dirent_name(sysnum, mcdirp),
dirent_name(sysnum, dirp))) {
memmove(_dirp + pos,
_dirp + pos + reclen,
ret + linux_ret - pos - reclen);
linux_ret -= reclen;
for (mcpos = 0; mcpos < ofd->mck_dirents_size;) {
mck_dirp_iter = ofd->mck_dirents + mcpos;
if (!strcmp(dirent_name(sysnum, mck_dirp_iter),
dirent_name(sysnum, linux_dirp_iter))) {
__dprintf("dupe: %s\n",
dirent_name(sysnum, mck_dirp_iter));
memmove(dirp + pos,
dirp + pos + reclen,
ret - pos - reclen);
ret -= reclen;
break;
}
mcpos += dirent_reclen(sysnum, mcdirp);
mcpos += dirent_reclen(sysnum, mck_dirp_iter);
}
if (mcpos >= ofd->dirents_size)
pos += reclen;
}
if (mcpos < ofd->mck_dirents_size)
continue;
ret += linux_ret;
pos += reclen;
}
linux_ret += ret;
__dprintf("getdents from lower: linux_ret: %d, ret: %d, count: %d\n",
linux_ret, ret, count);
/* cache Linux dirents to our buffer, in case of split getdents */
if (ret > 0) {
void *newbuf = realloc(ofd->linux_dirents,
ofd->linux_dirents_size + ret);
if (!newbuf) {
fprintf(stderr, "%s: not enough memory (%zd)",
__func__, ofd->linux_dirents_size + ret);
return ret;
}
ofd->linux_dirents = newbuf;
memcpy(ofd->linux_dirents + ofd->linux_dirents_size,
dirp, ret);
ofd->linux_dirents_size += ret;
/* Rewrite d_off to match the packed data layout.
* Rewrite all because ofd->mck_dirents_size might
* have changed.
*/
for (pos = 0; pos < ofd->linux_dirents_size;) {
linux_dirp_iter = ofd->linux_dirents + pos;
reclen = dirent_reclen(sysnum, linux_dirp_iter);
#ifdef DEBUG
printf("<%s,%d,%ld> ",
dirent_name(sysnum, linux_dirp_iter),
dirent_reclen(sysnum, linux_dirp_iter),
*((unsigned long *)
dirent_off(sysnum, linux_dirp_iter)));
#endif
*((unsigned long *)
dirent_off(sysnum, linux_dirp_iter)) =
ofd->mck_dirents_size + pos + reclen;
pos += reclen;
}
#ifdef DEBUG
printf("\n");
#endif
}
/* It's possible we filtered everything out, but there is more
* available. Keep trying!
*/
if (linux_ret == 0 || count - ret > 500)
goto again;
if (ret_before_edit > 0 && mck_ret + linux_ret < count) {
goto linux_again;
}
/* concatenate cached upper and lower and lseek */
/* TODO: this error should be detected by lseek */
if (offset > ofd->mck_dirents_size + ofd->linux_dirents_size) {
fprintf(stderr, "%s: offset (%ld) is too large (upper: %ld, lower: %ld)\n",
__func__, offset, ofd->mck_dirents_size,
ofd->linux_dirents_size);
ret = -EINVAL;
goto err;
}
mck_len = 0;
linux_len = 0;
if (count > 0 && offset < ofd->mck_dirents_size) {
mck_len = copy_dirents(_dirp, ofd->mck_dirents,
ofd->mck_dirents_size, offset,
&count, sysnum);
/* Result buffer is too small */
if (mck_len == 0) {
__dprintf("upper: Result buffer is too small\n");
ret = -EINVAL;
goto err;
}
offset = 0;
} else {
offset -= ofd->mck_dirents_size;
}
__dprintf("mck_dirents_size: %ld, offset: %ld, mck_len: %d, count: %d\n",
ofd->mck_dirents_size, offset,
mck_len, count);
if (count > 0 && offset < ofd->linux_dirents_size) {
linux_len = copy_dirents(_dirp + mck_len, ofd->linux_dirents,
ofd->linux_dirents_size, offset,
&count, sysnum);
/* Result buffer is too small */
if (mck_len == 0 && linux_len == 0) {
__dprintf("lower: Result buffer is too small\n");
ret = -EINVAL;
goto err;
}
__dprintf("linux_dirents_size: %ld, offset: %ld, linux_len: %d, count: %d\n",
ofd->linux_dirents_size, offset,
linux_len, count);
}
ret = mck_len + linux_len;
lseek(fd, ret, SEEK_CUR);
out_mck_only:
err:
free(dirp);
#ifdef DEBUG
{
void *dirp_iter;
printf("ret: %d, {<d_name,d_reclen,d_off>}: ", ret);
for (pos = 0; pos < ret;
pos += dirent_reclen(sysnum, dirp_iter)) {
dirp_iter = _dirp + pos;
printf("<%s,%d,%ld> ",
dirent_name(sysnum, dirp_iter),
dirent_reclen(sysnum, dirp_iter),
*((unsigned long *)dirent_off(sysnum, dirp_iter))
);
}
printf("\n");
}
#endif
return ret;
}

129
test/issues/1421/1421.c Normal file
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@ -0,0 +1,129 @@
// test getdents d_off and lseek are coherent
#define _GNU_SOURCE
#include <dirent.h> /* Defines DT_* constants */
#include <fcntl.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#define handle_error(msg) \
do { perror(msg); exit(EXIT_FAILURE); } while (0)
struct linux_dirent {
long d_ino;
off_t d_off;
unsigned short d_reclen;
char d_name[];
};
#define OFF_TABLE_SIZE (1UL << 20)
#define RECLEN_TABLE_SIZE (1UL << 20)
void print_dirent(char *buf, int bpos)
{
struct linux_dirent *d;
char d_type;
d = (struct linux_dirent *) (buf + bpos);
printf("%8ld ", d->d_ino);
d_type = *(buf + bpos + d->d_reclen - 1);
printf("%-10s ", (d_type == DT_REG) ? "regular" :
(d_type == DT_DIR) ? "directory" :
(d_type == DT_FIFO) ? "FIFO" :
(d_type == DT_SOCK) ? "socket" :
(d_type == DT_LNK) ? "symlink" :
(d_type == DT_BLK) ? "block dev" :
(d_type == DT_CHR) ? "char dev" : "???");
printf("%4d %10lld %s\n", d->d_reclen,
(long long) d->d_off, (char *) d->d_name);
}
int
main(int argc, char *argv[])
{
int fd, nread;
int buf_size = argc > 2 ? atoi(argv[2]) : 40;
char *buf;
struct linux_dirent *d;
int bpos;
off_t *off_table;
int off_table_size = 0;
unsigned short *reclen_table;
int reclen_table_size = 0;
int i;
buf = malloc(buf_size);
if (!buf)
handle_error("allocating buf");
off_table = malloc(OFF_TABLE_SIZE * sizeof(off_t));
if (!off_table)
handle_error("allocating off_table");
off_table[off_table_size++] = 0;
reclen_table = malloc(RECLEN_TABLE_SIZE * sizeof(unsigned short));
if (!reclen_table)
handle_error("allocating reclen_table");
fd = open(argc > 1 ? argv[1] : ".", O_RDONLY | O_DIRECTORY);
if (fd == -1)
handle_error("open");
for ( ; ; ) {
nread = syscall(SYS_getdents, fd, buf, buf_size);
if (nread == -1)
handle_error("getdents");
if (nread == 0)
break;
printf("--------------- nread=%d ---------------\n", nread);
printf("i-node# file type d_reclen d_off d_name\n");
for (bpos = 0; bpos < nread;) {
d = (struct linux_dirent *) (buf + bpos);
print_dirent(buf, bpos);
off_table[off_table_size++] = d->d_off;
reclen_table[reclen_table_size++] = d->d_reclen;
bpos += d->d_reclen;
}
printf("at end of getdents: lseek %10lld\n",
lseek(fd, 0, SEEK_CUR));
}
for (i = 0; i < off_table_size; i++) {
lseek(fd, off_table[i], SEEK_SET);
printf("lseek to %ld: lseek %10lld\n",
off_table[i], lseek(fd, 0, SEEK_CUR));
nread = syscall(SYS_getdents, fd, buf, reclen_table[i] - 1);
if (i != off_table_size - 1) {
if (nread == -1 && errno == EINVAL) {
printf("[ OK ] EINVAL for too small count\n");
} else {
printf("[ NG ] EINVAL for too small count\n");
handle_error("Test failed");
}
}
nread = syscall(SYS_getdents, fd, buf, buf_size);
if (nread == -1)
handle_error("getdents");
if (nread == 0) {
printf("--------------- nread=%d (EOF) ---------\n",
nread);
if (i != off_table_size - 1)
handle_error("unexpected EOF");
} else {
printf("--------------- nread=%d ---------------\n",
nread);
printf("i-node# file type d_reclen d_off d_name\n");
for (bpos = 0; bpos < nread;) {
d = (struct linux_dirent *) (buf + bpos);
print_dirent(buf, bpos);
bpos += d->d_reclen;
}
}
printf("at end of getdents: lseek %10lld\n",
lseek(fd, 0, SEEK_CUR));
}
exit(EXIT_SUCCESS);
}

11
test/issues/1421/Makefile Normal file
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@ -0,0 +1,11 @@
include $(HOME)/.mck_test_config.mk
TARGET=1421
all: $(TARGET)
test: $(TARGET)
@echo "===== getdents count: 40"
$(MCK_DIR)/bin/mcexec ./$(TARGET) /sys/devices/system/node 40
@printf "\n===== getdents count: 200\n"
$(MCK_DIR)/bin/mcexec ./$(TARGET) /sys/devices/system/node 200

13
test/issues/1421/README Normal file
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@ -0,0 +1,13 @@
============
What to test
============
(1) lseek value after a getdents matches the d_off of the last entry
received.
(2) lseek using d_off and then getdents gets the proper entry.
(3) lseek using d_off and then getdents with (d_reclen -1) returns EINVAL.
===========
How to test
===========
(1) make test
(2) Check the result manually.

179
test/issues/1421/result_x86_64.txt Normal file
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@ -0,0 +1,179 @@
cc 1421.c -o 1421
===== getdents count: 40
/work/gg10/e29005/project/os/install/bin/mcexec ./1421 /sys/devices/system/node 40
--------------- nread=24 ---------------
i-node# file type d_reclen d_off d_name
61145 directory 24 24 .
at end of getdents: lseek 24
--------------- nread=24 ---------------
i-node# file type d_reclen d_off d_name
46533 directory 24 48 ..
at end of getdents: lseek 48
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
61156 directory 32 80 node0
at end of getdents: lseek 80
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
61148 directory 32 112 node1
at end of getdents: lseek 112
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
61147 regular 32 144 possible
at end of getdents: lseek 144
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
61146 regular 32 176 online
at end of getdents: lseek 176
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
18112 directory 32 208 power
at end of getdents: lseek 208
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
18106 regular 32 240 uevent
at end of getdents: lseek 240
lseek to 0: lseek 0
[ OK ] EINVAL for too small count
--------------- nread=24 ---------------
i-node# file type d_reclen d_off d_name
61145 directory 24 24 .
at end of getdents: lseek 24
lseek to 24: lseek 24
[ OK ] EINVAL for too small count
--------------- nread=24 ---------------
i-node# file type d_reclen d_off d_name
46533 directory 24 48 ..
at end of getdents: lseek 48
lseek to 48: lseek 48
[ OK ] EINVAL for too small count
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
61156 directory 32 80 node0
at end of getdents: lseek 80
lseek to 80: lseek 80
[ OK ] EINVAL for too small count
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
61148 directory 32 112 node1
at end of getdents: lseek 112
lseek to 112: lseek 112
[ OK ] EINVAL for too small count
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
61147 regular 32 144 possible
at end of getdents: lseek 144
lseek to 144: lseek 144
[ OK ] EINVAL for too small count
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
61146 regular 32 176 online
at end of getdents: lseek 176
lseek to 176: lseek 176
[ OK ] EINVAL for too small count
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
18112 directory 32 208 power
at end of getdents: lseek 208
lseek to 208: lseek 208
[ OK ] EINVAL for too small count
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
18106 regular 32 240 uevent
at end of getdents: lseek 240
lseek to 240: lseek 240
--------------- nread=0 (EOF) ---------
at end of getdents: lseek 240
===== getdents count: 200
/work/gg10/e29005/project/os/install/bin/mcexec ./1421 /sys/devices/system/node 200
--------------- nread=176 ---------------
i-node# file type d_reclen d_off d_name
61145 directory 24 24 .
46533 directory 24 48 ..
61156 directory 32 80 node0
61148 directory 32 112 node1
61147 regular 32 144 possible
61146 regular 32 176 online
at end of getdents: lseek 176
--------------- nread=64 ---------------
i-node# file type d_reclen d_off d_name
18112 directory 32 208 power
18106 regular 32 240 uevent
at end of getdents: lseek 240
lseek to 0: lseek 0
[ OK ] EINVAL for too small count
--------------- nread=176 ---------------
i-node# file type d_reclen d_off d_name
61145 directory 24 24 .
46533 directory 24 48 ..
61156 directory 32 80 node0
61148 directory 32 112 node1
61147 regular 32 144 possible
61146 regular 32 176 online
at end of getdents: lseek 176
lseek to 24: lseek 24
[ OK ] EINVAL for too small count
--------------- nread=184 ---------------
i-node# file type d_reclen d_off d_name
46533 directory 24 48 ..
61156 directory 32 80 node0
61148 directory 32 112 node1
61147 regular 32 144 possible
61146 regular 32 176 online
18112 directory 32 208 power
at end of getdents: lseek 208
lseek to 48: lseek 48
[ OK ] EINVAL for too small count
--------------- nread=192 ---------------
i-node# file type d_reclen d_off d_name
61156 directory 32 80 node0
61148 directory 32 112 node1
61147 regular 32 144 possible
61146 regular 32 176 online
18112 directory 32 208 power
18106 regular 32 240 uevent
at end of getdents: lseek 240
lseek to 80: lseek 80
[ OK ] EINVAL for too small count
--------------- nread=160 ---------------
i-node# file type d_reclen d_off d_name
61148 directory 32 112 node1
61147 regular 32 144 possible
61146 regular 32 176 online
18112 directory 32 208 power
18106 regular 32 240 uevent
at end of getdents: lseek 240
lseek to 112: lseek 112
[ OK ] EINVAL for too small count
--------------- nread=128 ---------------
i-node# file type d_reclen d_off d_name
61147 regular 32 144 possible
61146 regular 32 176 online
18112 directory 32 208 power
18106 regular 32 240 uevent
at end of getdents: lseek 240
lseek to 144: lseek 144
[ OK ] EINVAL for too small count
--------------- nread=96 ---------------
i-node# file type d_reclen d_off d_name
61146 regular 32 176 online
18112 directory 32 208 power
18106 regular 32 240 uevent
at end of getdents: lseek 240
lseek to 176: lseek 176
[ OK ] EINVAL for too small count
--------------- nread=64 ---------------
i-node# file type d_reclen d_off d_name
18112 directory 32 208 power
18106 regular 32 240 uevent
at end of getdents: lseek 240
lseek to 208: lseek 208
[ OK ] EINVAL for too small count
--------------- nread=32 ---------------
i-node# file type d_reclen d_off d_name
18106 regular 32 240 uevent
at end of getdents: lseek 240
lseek to 240: lseek 240
--------------- nread=0 (EOF) ---------
at end of getdents: lseek 240