On 10/31/2017 11:40 AM, Marc-André Lureau wrote:
> Those functions are called for memfd files, backed by shmem or
> hugetlb (the next patches will handle hugetlb).
>
> Signed-off-by: Marc-André Lureau <[email protected]>
> ---
> fs/fcntl.c | 2 +-
> include/linux/shmem_fs.h | 4 ++--
> mm/shmem.c | 10 +++++-----
> 3 files changed, 8 insertions(+), 8 deletions(-)
>
> diff --git a/fs/fcntl.c b/fs/fcntl.c
> index 448a1119f0be..752c23743616 100644
> --- a/fs/fcntl.c
> +++ b/fs/fcntl.c
> @@ -417,7 +417,7 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned
> long arg,
> break;
> case F_ADD_SEALS:
> case F_GET_SEALS:
> - err = shmem_fcntl(filp, cmd, arg);
> + err = memfd_fcntl(filp, cmd, arg);
> break;
> case F_GET_RW_HINT:
> case F_SET_RW_HINT:
> diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
> index 557d0c3b6eca..0dac8c0f4aa4 100644
> --- a/include/linux/shmem_fs.h
> +++ b/include/linux/shmem_fs.h
> @@ -109,11 +109,11 @@ extern void shmem_uncharge(struct inode *inode, long
> pages);
>
> #ifdef CONFIG_TMPFS
>
> -extern long shmem_fcntl(struct file *file, unsigned int cmd, unsigned long
> arg);
> +extern long memfd_fcntl(struct file *file, unsigned int cmd, unsigned long
> arg);
>
> #else
>
> -static inline long shmem_fcntl(struct file *f, unsigned int c, unsigned long
> a)
> +static inline long memfd_fcntl(struct file *f, unsigned int c, unsigned long
> a)
> {
> return -EINVAL;
> }
Do we want memfd_fcntl() to work for hugetlbfs if CONFIG_TMPFS is not
defined? I admit that having CONFIG_HUGETLBFS defined without CONFIG_TMPFS
is unlikely, but I think possible. Based on the above #ifdef/#else, I
think hugetlbfs seals will not work if CONFIG_TMPFS is not defined.
--
Mike Kravetz
> diff --git a/mm/shmem.c b/mm/shmem.c
> index 37260c5e12fa..b7811979611f 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -2722,7 +2722,7 @@ static int shmem_wait_for_pins(struct address_space
> *mapping)
> F_SEAL_GROW | \
> F_SEAL_WRITE)
>
> -static int shmem_add_seals(struct file *file, unsigned int seals)
> +static int memfd_add_seals(struct file *file, unsigned int seals)
> {
> struct inode *inode = file_inode(file);
> struct shmem_inode_info *info = SHMEM_I(inode);
> @@ -2792,7 +2792,7 @@ static int shmem_add_seals(struct file *file, unsigned
> int seals)
> return error;
> }
>
> -static int shmem_get_seals(struct file *file)
> +static int memfd_get_seals(struct file *file)
> {
> if (file->f_op != &shmem_file_operations)
> return -EINVAL;
> @@ -2800,7 +2800,7 @@ static int shmem_get_seals(struct file *file)
> return SHMEM_I(file_inode(file))->seals;
> }
>
> -long shmem_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
> +long memfd_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
> {
> long error;
>
> @@ -2810,10 +2810,10 @@ long shmem_fcntl(struct file *file, unsigned int cmd,
> unsigned long arg)
> if (arg > UINT_MAX)
> return -EINVAL;
>
> - error = shmem_add_seals(file, arg);
> + error = memfd_add_seals(file, arg);
> break;
> case F_GET_SEALS:
> - error = shmem_get_seals(file);
> + error = memfd_get_seals(file);
> break;
> default:
> error = -EINVAL;
>
