From 319c10427498620d220931189dcdba7d4244feba Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Wed, 31 May 2017 11:40:27 +0200 Subject: [PATCH] ubifs: allow userspace to map mounts to volumes There currently appears to be no way for userspace to find out the underlying volume number for a mounted ubifs file system, since ubifs uses anonymous block devices. The volume name is present in /proc/mounts but UBI volumes can be renamed after the volume has been mounted. To remedy this, show the UBI number and UBI volume number as part of the options visible under /proc/mounts. Also, accept and ignore the ubi= vol= options if they are used mounting (patch from Richard Weinberger). # mount -t ubifs ubi:baz x # mount ubi:baz on /root/x type ubifs (rw,relatime,ubi=0,vol=2) # ubirename /dev/ubi0 baz bazz # mount ubi:baz on /root/x type ubifs (rw,relatime,ubi=0,vol=2) # ubinfo -d 0 -n 2 Volume ID: 2 (on ubi0) Type: dynamic Alignment: 1 Size: 67 LEBs (1063424 bytes, 1.0 MiB) State: OK Name: bazz Character device major/minor: 254:3 Signed-off-by: Rabin Vincent Signed-off-by: Richard Weinberger --- fs/ubifs/super.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c index ce684f367f9c1..845c5d7af9091 100644 --- a/fs/ubifs/super.c +++ b/fs/ubifs/super.c @@ -446,6 +446,8 @@ static int ubifs_show_options(struct seq_file *s, struct dentry *root) ubifs_compr_name(c->mount_opts.compr_type)); } + seq_printf(s, ",ubi=%d,vol=%d", c->vi.ubi_num, c->vi.vol_id); + return 0; } @@ -931,6 +933,7 @@ enum { Opt_chk_data_crc, Opt_no_chk_data_crc, Opt_override_compr, + Opt_ignore, Opt_err, }; @@ -942,6 +945,8 @@ static const match_table_t tokens = { {Opt_chk_data_crc, "chk_data_crc"}, {Opt_no_chk_data_crc, "no_chk_data_crc"}, {Opt_override_compr, "compr=%s"}, + {Opt_ignore, "ubi=%s"}, + {Opt_ignore, "vol=%s"}, {Opt_err, NULL}, }; @@ -1042,6 +1047,8 @@ static int ubifs_parse_options(struct ubifs_info *c, char *options, c->default_compr = c->mount_opts.compr_type; break; } + case Opt_ignore: + break; default: { unsigned long flag; -- 2.39.5