struct mnt_namespace {
bool read_mountinfo;
ino_t id;
+ struct list_head cooked_bdevs;
};
static struct mnt_namespace *find_mnt_ns(ino_t id);
static struct mnt_namespace *add_mnt_ns(ino_t id);
static void *mnt_namespaces; /* for tsearch/tfind */
+struct cooked_bdev {
+ struct list_head cooked_bdevs;
+ dev_t cooked;
+ dev_t raw;
+ char *filesystem;
+};
+
+static ino_t self_mntns_id;
+static int self_mntns_fd = -1;
+
struct name_manager {
struct idcache *cache;
unsigned long next_id;
false);
}
+static void reset_cooked_bdev(struct cooked_bdev *bdev, dev_t raw, const char *filesystem)
+{
+ bdev->raw = raw;
+ free(bdev->filesystem);
+ bdev->filesystem = xstrdup(filesystem);
+}
+
+static struct cooked_bdev *new_cooked_bdev(dev_t cooked, dev_t raw, const char *filesystem)
+{
+ struct cooked_bdev *bdev = xmalloc(sizeof(*bdev));
+
+ INIT_LIST_HEAD(&bdev->cooked_bdevs);
+ bdev->cooked = cooked;
+ bdev->raw = raw;
+ if (major(cooked) == 0) {
+ bdev->filesystem = NULL;
+ xasprintf(&bdev->filesystem, "%s:%lu",
+ filesystem, (unsigned long)minor(cooked));
+ } else
+ bdev->filesystem = xstrdup(filesystem);
+
+ return bdev;
+}
+
+static void free_cooked_bdev(struct cooked_bdev* bdev)
+{
+ if (bdev->filesystem)
+ free(bdev->filesystem);
+ free(bdev);
+}
+
+static void add_cooked_bdev(struct mnt_namespace *mnt_ns, dev_t cooked, dev_t raw, const char *filesystem)
+{
+ struct cooked_bdev *bdev;
+
+ struct list_head *n;
+ list_for_each (n, &mnt_ns->cooked_bdevs) {
+ bdev = list_entry(n, struct cooked_bdev, cooked_bdevs);
+ if (bdev->cooked == cooked) {
+ reset_cooked_bdev (bdev, raw, filesystem);
+ return;
+ }
+ }
+
+ bdev = new_cooked_bdev(cooked, raw, filesystem);
+ list_add_tail(&bdev->cooked_bdevs, &mnt_ns->cooked_bdevs);
+}
+
+static void dedup_cooked_bdevs(struct mnt_namespace *mnt_ns)
+{
+ struct list_head *n, *nnext;
+
+ list_for_each_safe(n, nnext, &mnt_ns->cooked_bdevs) {
+ struct cooked_bdev *bdev = list_entry(n, struct cooked_bdev,
+ cooked_bdevs);
+ if (bdev->cooked == bdev->raw) {
+ list_del(n);
+ free_cooked_bdev(bdev);
+ }
+ }
+
+#if 0
+ list_for_each(n, &mnt_ns->cooked_bdevs) {
+ struct cooked_bdev *bdev = list_entry(n, struct cooked_bdev,
+ cooked_bdevs);
+ fprintf(stderr, "mntns: %lu (major: %u, minor: %u) => (major: %u, minor: %u)\n",
+ mnt_ns->id,
+ major(bdev->cooked), minor(bdev->cooked),
+ major(bdev->raw), minor(bdev->raw));
+ }
+#endif
+}
+
static struct mnt_namespace *new_mnt_ns(ino_t id)
{
struct mnt_namespace *mnt_ns = xmalloc(sizeof(*mnt_ns));
mnt_ns->id = id;
mnt_ns->read_mountinfo = false;
+ INIT_LIST_HEAD(&mnt_ns->cooked_bdevs);
return mnt_ns;
}
static void free_mnt_ns(void *mnt_ns)
{
+ list_free(&((struct mnt_namespace *)mnt_ns)->cooked_bdevs,
+ struct cooked_bdev, cooked_bdevs, free_cooked_bdev);
+
free(mnt_ns);
}
static void initialize_nodevs(void)
{
int i;
+ struct stat sb;
for (i = 0; i < NODEV_TABLE_SIZE; i++)
INIT_LIST_HEAD(&nodev_table.tables[i]);
+
+ if (stat("/proc/self/ns/mnt", &sb) == 0) {
+ self_mntns_id = sb.st_ino;
+ self_mntns_fd = open("/proc/self/ns/mnt", O_RDONLY);
+ }
}
static void finalize_nodevs(void)
{
int i;
+ if (self_mntns_fd >= 0)
+ close(self_mntns_fd);
+
for (i = 0; i < NODEV_TABLE_SIZE; i++)
list_free(&nodev_table.tables[i], struct nodev, nodevs, free_nodev);
return NULL;
}
-static void process_mountinfo_entry(unsigned long major, unsigned long minor,
- const char *filesystem)
+static void add_nodevs_from_cooked_bdevs(struct mnt_namespace *mnt_ns)
{
+ struct list_head *n;
+ list_for_each(n, &mnt_ns->cooked_bdevs) {
+ struct cooked_bdev *bdev = list_entry(n, struct cooked_bdev,
+ cooked_bdevs);
+ if (major(bdev->cooked) == 0
+ && get_nodev_filesystem(minor(bdev->cooked)) == NULL)
+ add_nodev(minor(bdev->cooked), bdev->filesystem);
+ }
+}
+
+static void process_mountinfo_entry(unsigned long major, unsigned long minor,
+ const char *filesystem,
+ const char *mntpoint_filename,
+ struct mnt_namespace *mnt_ns)
+{
+ if (mnt_ns != NULL) {
+ struct stat sb;
+ if (stat(mntpoint_filename, &sb) == 0)
+ add_cooked_bdev(mnt_ns, sb.st_dev, makedev(major, minor), filesystem);
+ }
+
if (major != 0)
return;
if (get_nodev_filesystem(minor))
add_nodev(minor, filesystem);
}
-static void read_mountinfo(FILE *mountinfo)
+static void read_mountinfo(FILE *mountinfo, struct mnt_namespace *mnt_ns)
{
/* This can be very long. A line in mountinfo can have more than 3
* paths. */
while (fgets(line, sizeof(line), mountinfo)) {
unsigned long major, minor;
char filesystem[256];
+ int mntpoint_offset, mntpoint_end_offset;
+ int scan_offset;
- /* 23 61 0:22 / /sys rw,nosuid,nodev,noexec,relatime shared:2 - sysfs sysfs rw,seclabel */
- if(sscanf(line, "%*d %*d %lu:%lu %*s %*s %*s %*[^-] - %255s %*[^\n]",
- &major, &minor, filesystem) != 3)
- /* 1600 1458 0:55 / / rw,nodev,relatime - overlay overlay rw,context="s... */
- if (sscanf(line, "%*d %*d %lu:%lu %*s %*s %*s - %255s %*[^\n]",
- &major, &minor, filesystem) != 3)
+ if(sscanf(line, "%*d %*d %lu:%lu %*s %n%*s%n %*s %n", &major, &minor,
+ &mntpoint_offset, &mntpoint_end_offset, &scan_offset) != 2)
+ continue;
+
+ /* 23 61 0:22 / /sys rw,nosuid,nodev,noexec,relatime shared:2 - sysfs sysfs rw,seclabel
+ * --------------------------------------------------^
+ */
+ if(sscanf(line + scan_offset, "%*[^-] - %255s %*[^\n]",
+ filesystem) != 1)
+ /* 1600 1458 0:55 / / rw,nodev,relatime - overlay overlay rw,context="s...
+ * -------------------------------------^
+ */
+ if (sscanf(line + scan_offset, "- %255s %*[^\n]",
+ filesystem) != 1)
continue;
- process_mountinfo_entry(major, minor, filesystem);
+ line[mntpoint_end_offset] = '\0';
+ process_mountinfo_entry(major, minor, filesystem,
+ line + mntpoint_offset, mnt_ns);
+ }
+
+ if (mnt_ns) {
+ dedup_cooked_bdevs(mnt_ns);
+ add_nodevs_from_cooked_bdevs(mnt_ns);
}
}
+static void read_mountinfo_in_mntns(FILE *mountinfo, struct mnt_namespace *mnt_ns,
+ int mntns_fd)
+{
+ if (mntns_fd >= 0 && setns(mntns_fd, CLONE_NEWNS) < 0) {
+ mntns_fd = -1;
+ mnt_ns = NULL;
+ }
+
+ read_mountinfo(mountinfo, mnt_ns);
+
+ if (mntns_fd >= 0)
+ setns(self_mntns_fd, CLONE_NEWNS);
+}
+
static void initialize_ipc_table(void)
{
for (int i = 0; i < IPC_TABLE_SIZE; i++)
if (proc->mnt_ns == NULL || !proc->mnt_ns->read_mountinfo) {
FILE *mountinfo = ul_path_fopen(pc, "r", "mountinfo");
if (mountinfo) {
- read_mountinfo(mountinfo);
+ int mntns_fd = -1;
+ if (proc->mnt_ns && (self_mntns_id != proc->mnt_ns->id))
+ mntns_fd = ul_path_open(pc, O_RDONLY, "ns/mnt");
+ read_mountinfo_in_mntns(mountinfo, proc->mnt_ns, mntns_fd);
+ if (mntns_fd >= 0)
+ close(mntns_fd);
if (proc->mnt_ns)
proc->mnt_ns->read_mountinfo = true;
fclose(mountinfo);
--- /dev/null
+#!/bin/bash
+#
+# Copyright (C) 2024 Masatake YAMATO <yamato@redhat.com>
+#
+# This file is part of util-linux.
+#
+# This file is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This file is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+TS_TOPDIR="${0%/*}/../.."
+TS_DESC="SOURCE column for fd opening a file on btrfs"
+
+. "$TS_TOPDIR"/functions.sh
+ts_init "$*"
+ts_skip_nonroot
+
+ts_check_test_command "$TS_CMD_LSFD"
+ts_check_prog "stat"
+ts_check_prog "sed"
+ts_check_prog "mkfs.btrfs"
+ts_check_prog "dd"
+
+ts_cd "$TS_OUTDIR"
+
+PID=
+FD=3
+
+IMG=img-column-source-btrfs.btrfs
+MNTPNT=mntpnt-column-source-btrfs
+FILE=${MNTPNT}/afile
+
+mkdir -p $MNTPNT
+dd if=/dev/zero of=$IMG bs=114294784 count=1 status=none
+if ! mkfs.btrfs -q $IMG; then
+ ts_skip "failed to make a btrfs image: $IMG"
+fi
+if ! mount $IMG $MNTPNT; then
+ ts_skip "failed to mount a btrfs image, $IMG to $MNTPNT"
+fi
+trap "umount $MNTPNT; rm -f $IMG" EXIT
+
+if ! touch $FILE; then
+ ts_skip "failed to touch a file on a btrfs filesystem: $FILE"
+fi
+
+# The major number may be 0. So we can assume the device number is the
+# same as that of minor number.
+EXPECTED="btrfs:$(stat -c %d $FILE)"
+
+{
+ coproc MKFDS { "$TS_HELPER_MKFDS" ro-regular-file $FD file=$FILE; }
+ if read -u ${MKFDS[0]} PID; then
+ EXPR='(PID == '"${PID}"') and (FD == '"$FD"')'
+ SOURCE=$(${TS_CMD_LSFD} -n --raw -o SOURCE -Q "${EXPR}")
+ echo "SOURCE": $?
+ if [[ "$SOURCE" == "$EXPECTED" ]]; then
+ echo "SOURCE == EXPECTED"
+ else
+ echo "SOURCE: $SOURCE"
+ echo "EXPECTED: $EXPECTED"
+ fi
+ echo DONE >&"${MKFDS[1]}"
+ fi
+ wait "${MKFDS_PID}"
+} > "$TS_OUTPUT" 2>&1
+
+ts_finalize
projects / thirdparty / util-linux.git / commitdiff
