On Wed, Dec 04, 2019 at 09:11:37PM +0800, yu kuai wrote:
> tmpfs support 'size', 'nr_blocks' and 'nr_inodes' mount options. mount or
> remount them to zero means unlimited. 'size' and 'br_blocks' can remount
> from limited to unlimited, while 'nr_inodes' can't.
>
> The problem is fixed since upstream commit 0b5071dd323d ("
> shmem_parse_options(): use a separate structure to keep the results"). But
> in order to backport it, the amount of related patches need to backport is
> huge.
>
> So, I made some local changes to fix the problem.
>
> Signed-off-by: yu kuai <yukuai3@xxxxxxxxxx>
> ---
> mm/shmem.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/mm/shmem.c b/mm/shmem.c
> index 3c8742655756..966fc69ee8fb 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -3444,7 +3444,7 @@ static int shmem_remount_fs(struct super_block *sb, int *flags, char *data)
> inodes = sbinfo->max_inodes - sbinfo->free_inodes;
> if (percpu_counter_compare(&sbinfo->used_blocks, config.max_blocks) > 0)
> goto out;
> - if (config.max_inodes < inodes)
> + if (config.max_inodes && config.max_inodes < inodes)
> goto out;
> /*
> * Those tests disallow limited->unlimited while any are in use;
> @@ -3460,7 +3460,10 @@ static int shmem_remount_fs(struct super_block *sb, int *flags, char *data)
> sbinfo->huge = config.huge;
> sbinfo->max_blocks = config.max_blocks;
> sbinfo->max_inodes = config.max_inodes;
> - sbinfo->free_inodes = config.max_inodes - inodes;
> + if (!config.max_inodes)
> + sbinfo->free_inodes = 0;
> + else
> + sbinfo->free_inodes = config.max_inodes - inodes;
>
> /*
> * Preserve previous mempolicy unless mpol remount option was specified.
> --
> 2.17.2
>
Hm, sorry about my bot, this looked like an odd one-off patch.
What about 5.3.y, should this patch also go there as well?
But is it really an issue as this is a new "feature" that 5.4 now has,
can't you just use 5.4.y if you need this type of thing? It's never
worked in the past, right?
thanks,
greg k-h
