[PATCH v6 06/22] cachefiles: enable on-demand read mode

Jeffle Xu
2022-03-25T12:24:33Z

Enable on-demand read mode by adding an optional parameter to the "bind"
command.

On-demand mode will be turned on when this parameter is "ondemand", i.e.
"bind ondemand". Otherwise cachefiles will work in the original mode.

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
---
fs/cachefiles/daemon.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c
index 91b88a499737..2c38c5361bda 100644
--- a/fs/cachefiles/daemon.c
+++ b/fs/cachefiles/daemon.c
@@ -741,11 +741,6 @@ static int cachefiles_daemon_bind(struct cachefiles_cache *cache, char *args)
cache->brun_percent >= 100)
return -ERANGE;

- if (*args) {
- pr_err("'bind' command doesn't take an argument\n");
- return -EINVAL;
- }
-
if (!cache->rootdirname) {
pr_err("No cache directory specified\n");
return -EINVAL;
@@ -757,6 +752,14 @@ static int cachefiles_daemon_bind(struct cachefiles_cache *cache, char *args)
return -EBUSY;
}

+ if (IS_ENABLED(CONFIG_CACHEFILES_ONDEMAND) &&
+ !strcmp(args, "ondemand")) {
+ set_bit(CACHEFILES_ONDEMAND_MODE, &cache->flags);
+ } else if (*args) {
+ pr_err("'bind' command doesn't take an argument\n");
+ return -EINVAL;
+ }
+
/* Make sure we have copies of the tag string */
if (!cache->tag) {
/*
--
2.27.0