On Wed, Feb 09, 2022 at 02:00:49PM +0800, Jeffle Xu wrote:
> ... so that the following new devnode can reuse most of the code when
> implementing its own methods.
>
Looks good.
Reviewed-by: Liu Bo <bo.liu@xxxxxxxxxxxxxxxxx>
liubo
> Signed-off-by: Jeffle Xu <jefflexu@xxxxxxxxxxxxxxxxx>
> ---
> fs/cachefiles/daemon.c | 70 +++++++++++++++++++++++++++---------------
> 1 file changed, 45 insertions(+), 25 deletions(-)
>
> diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c
> index 7ac04ee2c0a0..6b8d7c5bbe5d 100644
> --- a/fs/cachefiles/daemon.c
> +++ b/fs/cachefiles/daemon.c
> @@ -78,6 +78,34 @@ static const struct cachefiles_daemon_cmd cachefiles_daemon_cmds[] = {
> { "", NULL }
> };
>
> +static struct cachefiles_cache *cachefiles_daemon_open_cache(void)
> +{
> + struct cachefiles_cache *cache;
> +
> + /* allocate a cache record */
> + cache = kzalloc(sizeof(struct cachefiles_cache), GFP_KERNEL);
> + if (cache) {
> + mutex_init(&cache->daemon_mutex);
> + init_waitqueue_head(&cache->daemon_pollwq);
> + INIT_LIST_HEAD(&cache->volumes);
> + INIT_LIST_HEAD(&cache->object_list);
> + spin_lock_init(&cache->object_list_lock);
> +
> + /* set default caching limits
> + * - limit at 1% free space and/or free files
> + * - cull below 5% free space and/or free files
> + * - cease culling above 7% free space and/or free files
> + */
> + cache->frun_percent = 7;
> + cache->fcull_percent = 5;
> + cache->fstop_percent = 1;
> + cache->brun_percent = 7;
> + cache->bcull_percent = 5;
> + cache->bstop_percent = 1;
> + }
> +
> + return cache;
> +}
>
> /*
> * Prepare a cache for caching.
> @@ -96,31 +124,13 @@ static int cachefiles_daemon_open(struct inode *inode, struct file *file)
> if (xchg(&cachefiles_open, 1) == 1)
> return -EBUSY;
>
> - /* allocate a cache record */
> - cache = kzalloc(sizeof(struct cachefiles_cache), GFP_KERNEL);
> +
> + cache = cachefiles_daemon_open_cache();
> if (!cache) {
> cachefiles_open = 0;
> return -ENOMEM;
> }
>
> - mutex_init(&cache->daemon_mutex);
> - init_waitqueue_head(&cache->daemon_pollwq);
> - INIT_LIST_HEAD(&cache->volumes);
> - INIT_LIST_HEAD(&cache->object_list);
> - spin_lock_init(&cache->object_list_lock);
> -
> - /* set default caching limits
> - * - limit at 1% free space and/or free files
> - * - cull below 5% free space and/or free files
> - * - cease culling above 7% free space and/or free files
> - */
> - cache->frun_percent = 7;
> - cache->fcull_percent = 5;
> - cache->fstop_percent = 1;
> - cache->brun_percent = 7;
> - cache->bcull_percent = 5;
> - cache->bstop_percent = 1;
> -
> file->private_data = cache;
> cache->cachefilesd = file;
> return 0;
> @@ -209,10 +219,11 @@ static ssize_t cachefiles_daemon_read(struct file *file, char __user *_buffer,
> /*
> * Take a command from cachefilesd, parse it and act on it.
> */
> -static ssize_t cachefiles_daemon_write(struct file *file,
> - const char __user *_data,
> - size_t datalen,
> - loff_t *pos)
> +static ssize_t cachefiles_daemon_do_write(struct file *file,
> + const char __user *_data,
> + size_t datalen,
> + loff_t *pos,
> + const struct cachefiles_daemon_cmd *cmds)
> {
> const struct cachefiles_daemon_cmd *cmd;
> struct cachefiles_cache *cache = file->private_data;
> @@ -261,7 +272,7 @@ static ssize_t cachefiles_daemon_write(struct file *file,
> }
>
> /* run the appropriate command handler */
> - for (cmd = cachefiles_daemon_cmds; cmd->name[0]; cmd++)
> + for (cmd = cmds; cmd->name[0]; cmd++)
> if (strcmp(cmd->name, data) == 0)
> goto found_command;
>
> @@ -284,6 +295,15 @@ static ssize_t cachefiles_daemon_write(struct file *file,
> goto error;
> }
>
> +static ssize_t cachefiles_daemon_write(struct file *file,
> + const char __user *_data,
> + size_t datalen,
> + loff_t *pos)
> +{
> + return cachefiles_daemon_do_write(file, _data, datalen, pos,
> + cachefiles_daemon_cmds);
> +}
> +
> /*
> * Poll for culling state
> * - use EPOLLOUT to indicate culling state
> --
> 2.27.0
