[PATCH 5.10 08/63] jffs2: Allow setting rp_size to zero during remounting

[Greg Kroah-Hartman]

From: lizhe <lizh...@huawei.com>

[ Upstream commit cd3ed3c73ac671ff6b0230ccb72b8300292d3643 ]

Set rp_size to zero will be ignore during remounting.

The method to identify whether we input a remounting option of
rp_size is to check if the rp_size input is zero. It can not work
well if we pass "rp_size=0".

This patch add a bool variable "set_rp_size" to fix this problem.

Reported-by: Jubin Zhong <zhongju...@huawei.com>
Signed-off-by: lizhe <lizh...@huawei.com>
Signed-off-by: Richard Weinberger <rich...@nod.at>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 fs/jffs2/jffs2_fs_sb.h | 1 +
 fs/jffs2/super.c       | 7 +++++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/jffs2/jffs2_fs_sb.h b/fs/jffs2/jffs2_fs_sb.h
index 778275f48a879..5a7091746f68b 100644
--- a/fs/jffs2/jffs2_fs_sb.h
+++ b/fs/jffs2/jffs2_fs_sb.h
@@ -38,6 +38,7 @@ struct jffs2_mount_opts {
         * users. This is implemented simply by means of not allowing the
         * latter users to write to the file system if the amount if the
         * available space is less then 'rp_size'. */
+       bool set_rp_size;
        unsigned int rp_size;
 };
 
diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
index 4fd297bdf0f3f..c523adaca79f3 100644
--- a/fs/jffs2/super.c
+++ b/fs/jffs2/super.c
@@ -88,7 +88,7 @@ static int jffs2_show_options(struct seq_file *s, struct 
dentry *root)
 
        if (opts->override_compr)
                seq_printf(s, ",compr=%s", jffs2_compr_name(opts->compr));
-       if (opts->rp_size)
+       if (opts->set_rp_size)
                seq_printf(s, ",rp_size=%u", opts->rp_size / 1024);
 
        return 0;
@@ -206,6 +206,7 @@ static int jffs2_parse_param(struct fs_context *fc, struct 
fs_parameter *param)
                if (opt > c->mtd->size)
                        return invalf(fc, "jffs2: Too large reserve pool 
specified, max is %llu KB",
                                      c->mtd->size / 1024);
+               c->mount_opts.set_rp_size = true;
                c->mount_opts.rp_size = opt;
                break;
        default:
@@ -225,8 +226,10 @@ static inline void jffs2_update_mount_opts(struct 
fs_context *fc)
                c->mount_opts.override_compr = new_c->mount_opts.override_compr;
                c->mount_opts.compr = new_c->mount_opts.compr;
        }
-       if (new_c->mount_opts.rp_size)
+       if (new_c->mount_opts.set_rp_size) {
+               c->mount_opts.set_rp_size = new_c->mount_opts.set_rp_size;
                c->mount_opts.rp_size = new_c->mount_opts.rp_size;
+       }
        mutex_unlock(&c->alloc_sem);
 }
 
-- 
2.27.0