Currently, the following commands succeed.
# cat /proc/swaps
Filename Type Size Used
Priority
/dev/sda3 partition 8388604 0 -1
/dev/sdc8 partition 9765884 0 -2
# mkfs.btrfs /dev/sdc8
WARNING! - Btrfs v0.20-rc1-165-g82ac345 IS EXPERIMENTAL
WARNING! - see http://btrfs.wiki.kernel.org before using
fs created label (null) on /dev/sdc8
nodesize 4096 leafsize 4096 sectorsize 4096 size 9.31GB
Btrfs v0.20-rc1-165-g82ac345
# btrfs fi sh /dev/sdc8
Label: none uuid: fc0bdbd0-7eed-460f-b4e9-131273b66df2
Total devices 1 FS bytes used 28.00KB
devid 1 size 9.31GB used 989.62MB path /dev/sdc8
Btrfs v0.20-rc1-165-g82ac345
#
But we should check out the swap device. Fixed it.
Signed-off-by: Tsutomu Itoh <[email protected]>
---
(this patch is based on Chris's raid56-experimental branch)
v1 -> v2:
- O_EXCL is specified at open(), as a last safety check
- check when the swap device is a file is added
- translate '\nnn'(octal) to character
Thank you Eric, David, Zach and others.
---
mkfs.c | 30 ++++++++++++++++++++++----
utils.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
utils.h | 1 +
3 files changed, 102 insertions(+), 4 deletions(-)
diff --git a/mkfs.c b/mkfs.c
index 2d3c2af..e981517 100644
--- a/mkfs.c
+++ b/mkfs.c
@@ -1366,6 +1366,16 @@ int main(int ac, char **av)
if (source_dir == 0) {
file = av[optind++];
+ ret = is_swap_device(file);
+ if (ret < 0) {
+ fprintf(stderr, "error checking %s status: %s\n", file,
+ strerror(-ret));
+ exit(1);
+ }
+ if (ret == 1) {
+ fprintf(stderr, "%s is a swap device\n", file);
+ exit(1);
+ }
ret = check_mounted(file);
if (ret < 0) {
fprintf(stderr, "error checking %s mount status\n",
file);
@@ -1376,9 +1386,10 @@ int main(int ac, char **av)
exit(1);
}
ac--;
- fd = open(file, O_RDWR);
+ fd = open(file, O_RDWR|O_EXCL);
if (fd < 0) {
- fprintf(stderr, "unable to open %s\n", file);
+ fprintf(stderr, "unable to open %s: %s\n", file,
+ strerror(errno));
exit(1);
}
first_file = file;
@@ -1461,6 +1472,16 @@ int main(int ac, char **av)
int old_mixed = mixed;
file = av[optind++];
+ ret = is_swap_device(file);
+ if (ret < 0) {
+ fprintf(stderr, "error checking %s status: %s\n", file,
+ strerror(-ret));
+ exit(1);
+ }
+ if (ret == 1) {
+ fprintf(stderr, "%s is a swap device\n", file);
+ exit(1);
+ }
ret = check_mounted(file);
if (ret < 0) {
fprintf(stderr, "error checking %s mount status\n",
@@ -1471,9 +1492,10 @@ int main(int ac, char **av)
fprintf(stderr, "%s is mounted\n", file);
exit(1);
}
- fd = open(file, O_RDWR);
+ fd = open(file, O_RDWR|O_EXCL);
if (fd < 0) {
- fprintf(stderr, "unable to open %s\n", file);
+ fprintf(stderr, "unable to open %s: %s\n", file,
+ strerror(errno));
exit(1);
}
ret = btrfs_device_already_in_root(root, fd,
diff --git a/utils.c b/utils.c
index f9ee812..891edcc 100644
--- a/utils.c
+++ b/utils.c
@@ -1386,3 +1386,78 @@ int get_fs_info(int fd, char *path, struct
btrfs_ioctl_fs_info_args *fi_args,
return 0;
}
+
+#define isoctal(c) (((c) & ~7) == '0')
+
+static inline void translate(char *f, char *t)
+{
+ while (*f != '\0') {
+ if (*f == '\\' &&
+ isoctal(f[1]) && isoctal(f[2]) && isoctal(f[3])) {
+ *t++ = 64*(f[1] & 7) + 8*(f[2] & 7) + (f[3] & 7);
+ f += 4;
+ } else
+ *t++ = *f++;
+ }
+ *t = '\0';
+ return;
+}
+
+/*
+ * Checks if the swap device.
+ * Returns 1 if swap device, < 0 on error or 0 if not swap device.
+ */
+int is_swap_device(const char *file)
+{
+ FILE *f;
+ struct stat st_buf;
+ dev_t dev;
+ ino_t ino = 0;
+ char tmp[PATH_MAX];
+ char buf[PATH_MAX];
+ char *cp;
+ int ret = 0;
+
+ if (stat(file, &st_buf) < 0)
+ return -errno;
+ if (S_ISBLK(st_buf.st_mode))
+ dev = st_buf.st_rdev;
+ else if (S_ISREG(st_buf.st_mode)) {
+ dev = st_buf.st_dev;
+ ino = st_buf.st_ino;
+ } else
+ return 0;
+
+ if ((f = fopen("/proc/swaps", "r")) == NULL)
+ return 0;
+
+ /* skip the first line */
+ if (fgets(tmp, sizeof(tmp), f) == NULL)
+ goto out;
+
+ while (fgets(tmp, sizeof(tmp), f) != NULL) {
+ if ((cp = strchr(tmp, ' ')) != NULL)
+ *cp = '\0';
+ if ((cp = strchr(tmp, '\t')) != NULL)
+ *cp = '\0';
+ translate(tmp, buf);
+ if (stat(buf, &st_buf) != 0)
+ continue;
+ if (S_ISBLK(st_buf.st_mode)) {
+ if (dev == st_buf.st_rdev) {
+ ret = 1;
+ break;
+ }
+ } else if (S_ISREG(st_buf.st_mode)) {
+ if (dev == st_buf.st_dev && ino == st_buf.st_ino) {
+ ret = 1;
+ break;
+ }
+ }
+ }
+
+out:
+ fclose(f);
+
+ return ret;
+}
diff --git a/utils.h b/utils.h
index bbcaf6a..60a0fea 100644
--- a/utils.h
+++ b/utils.h
@@ -55,6 +55,7 @@ int get_fs_info(int fd, char *path, struct
btrfs_ioctl_fs_info_args *fi_args,
struct btrfs_ioctl_dev_info_args **di_ret);
char *__strncpy__null(char *dest, const char *src, size_t n);
+int is_swap_device(const char *file);
/* Helper to always get proper size of the destination string */
#define strncpy_null(dest, src) __strncpy__null(dest, src, sizeof(dest))
--
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