Add bcachefs support

bcachefs multi device filesystems require a bit of hackery, since the
line in /proc/mounts isn't actually a device: when checking if a
bcachefs device has quotas, we return an actually device path in @dev.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

4 files changed, 27 insertions, 5 deletions

diff --git a/bylabel.c b/bylabel.c
index 069c3a1..fc20ef4 100644
--- a/bylabel.c
+++ b/bylabel.c
@@ -280,9 +280,9 @@ static char *get_spec_by_volume_label(const char *s)
 	return get_spec_by_x(VOL, s);
 }
 
-const char *get_device_name(const char *item)
+char *get_device_name(const char *item)
 {
-	const char *rc;
+	char *rc;
 
 	if (!strncmp(item, "UUID=", 5))
 		rc = get_spec_by_uuid(item + 5);
diff --git a/bylabel.h b/bylabel.h
index 12fc725..e77875e 100644
--- a/bylabel.h
+++ b/bylabel.h
@@ -1,4 +1,4 @@
 #ifndef BYLABEL_H_
 #define BYLABEL_H_
-const char *get_device_name(const char *item);
+char *get_device_name(const char *item);
 #endif /* BYLABEL_H_ */
diff --git a/mntopt.h b/mntopt.h
index 9b71990..d74f4f5 100644
--- a/mntopt.h
+++ b/mntopt.h
@@ -23,6 +23,7 @@
 #define MNTTYPE_OCFS2		"ocfs2"	/* Oracle Cluster filesystem */
 #define MNTTYPE_GFS2		"gfs2"	/* Red Hat Global filesystem 2 */
 #define MNTTYPE_TMPFS		"tmpfs"	/* tmpfs filesystem */
+#define MNTTYPE_BCACHEFS	"bcachefs"
 
 #ifndef MNTTYPE_NFS
 #define MNTTYPE_NFS	"nfs"		/* Network file system.  */
diff --git a/quotasys.c b/quotasys.c
index afe5f6d..abbdfec 100644
--- a/quotasys.c
+++ b/quotasys.c
@@ -764,6 +764,24 @@ static int hasvfsmetaquota(const char *dev, struct mntent *mnt, int type, int fl
 	return QF_ERROR;
 }
 
+static int hasbcachefsquota(char *dev, struct mntent *mnt, int type, int flags)
+{
+	/* For multi device filesytems, figure out which is the right device: */
+	char *devs = strdup(dev), *p = devs, *d;
+	uint32_t fmt;
+
+	while ((d = strsep(&p, ":"))) {
+		if (!quotactl(QCMD(Q_XFS_GETQSTAT, type), d, 0, (void *)&fmt)) {
+			strcpy(dev, d);
+			free(devs);
+			return QF_META;
+		}
+	}
+
+	free(devs);
+	return QF_ERROR;
+}
+
 /* Return pointer to given mount option in mount option string */
 char *str_hasmntopt(const char *optstring, const char *opt)
 {
@@ -819,7 +837,7 @@ static void copy_mntoptarg(char *buf, const char *optarg, int buflen)
 /*
  *	Check to see if a particular quota is to be enabled (filesystem mounted with proper option)
  */
-static int hasquota(const char *dev, struct mntent *mnt, int type, int flags)
+static int hasquota(char *dev, struct mntent *mnt, int type, int flags)
 {
 	if (!strcmp(mnt->mnt_type, MNTTYPE_GFS2) ||
 	    !strcmp(mnt->mnt_type, MNTTYPE_XFS) ||
@@ -832,6 +850,9 @@ static int hasquota(const char *dev, struct mntent *mnt, int type, int flags)
 	/* tmpfs has no device, pass null here so quotactl_fd() is called */
 	if (!strcmp(mnt->mnt_type, MNTTYPE_TMPFS))
 		return hasvfsmetaquota(NULL, mnt, type, flags);
+
+	if (!strcmp(mnt->mnt_type, MNTTYPE_BCACHEFS))
+		return hasbcachefsquota(dev, mnt, type, flags) != QF_ERROR ? QF_META : QF_ERROR;
 	/*
 	 * For ext4 we check whether it has quota in system files and if not,
 	 * we fall back on checking standard quotas. Furthermore we cannot use
@@ -1317,7 +1338,7 @@ alloc:
 	autofsdircnt = 0;
 	autofsdir_allocated = ALLOC_ENTRIES_NUM;
 	while ((mnt = getmntent(mntf))) {
-		const char *devname;
+		char *devname;
 		char *opt;
 		int qfmt[MAXQUOTAS];