On Fri, Jul 16, 2021 at 06:47:51PM +0800, Jeffle Xu
wrote:> We add 'always', 'never', and 'inode' (default).
'-o dax' continues to
> operate the same which is equivalent to 'always'.
>
> By the time this patch is applied, 'inode' mode is actually equal
to
> 'always' mode, before the per-file DAX flag is introduced in the
> following patch.
>
> Signed-off-by: Jeffle Xu <jefflexu at linux.alibaba.com>
> ---
> fs/fuse/dax.c | 13 ++++++++++++-
> fs/fuse/fuse_i.h | 11 +++++++++--
> fs/fuse/inode.c | 2 +-
> fs/fuse/virtio_fs.c | 16 ++++++++++++++--
> 4 files changed, 36 insertions(+), 6 deletions(-)
>
> diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c
> index c6f4e82e65f3..a478e824c2d0 100644
> --- a/fs/fuse/dax.c
> +++ b/fs/fuse/dax.c
> @@ -70,6 +70,9 @@ struct fuse_inode_dax {
> };
>
> struct fuse_conn_dax {
> + /** dax mode: FUSE_DAX_MOUNT_* (always, never or per-file) **/
> + unsigned int mode;
Why "/**" ?
How about make it something like "enum fuse_dax_mode mode" instead?
enum fuse_dax_mode dax_mode;
> +
> /* DAX device */
> struct dax_device *dev;
>
> @@ -1288,7 +1291,8 @@ static int fuse_dax_mem_range_init(struct
fuse_conn_dax *fcd)
> return ret;
> }
>
> -int fuse_dax_conn_alloc(struct fuse_conn *fc, struct dax_device *dax_dev)
> +int fuse_dax_conn_alloc(struct fuse_conn *fc, unsigned int mode,
> + struct dax_device *dax_dev)
> {
> struct fuse_conn_dax *fcd;
> int err;
> @@ -1301,6 +1305,7 @@ int fuse_dax_conn_alloc(struct fuse_conn *fc, struct
dax_device *dax_dev)
> return -ENOMEM;
>
> spin_lock_init(&fcd->lock);
> + fcd->mode = mode;
> fcd->dev = dax_dev;
> err = fuse_dax_mem_range_init(fcd);
> if (err) {
> @@ -1339,10 +1344,16 @@ static const struct address_space_operations
fuse_dax_file_aops = {
> static bool fuse_should_enable_dax(struct inode *inode)
> {
> struct fuse_conn *fc = get_fuse_conn(inode);
> + unsigned int mode;
>
> if (!fc->dax)
> return false;
>
> + mode = fc->dax->mode;
> +
> + if (mode == FUSE_DAX_MOUNT_NEVER)
> + return false;
> +
> return true;
> }
>
> diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
> index 07829ce78695..f29018323845 100644
> --- a/fs/fuse/fuse_i.h
> +++ b/fs/fuse/fuse_i.h
> @@ -487,6 +487,12 @@ struct fuse_dev {
> struct list_head entry;
> };
>
> +enum {
And this becomes.
enum fuse_dax_mode {
};
> + FUSE_DAX_MOUNT_INODE,
> + FUSE_DAX_MOUNT_ALWAYS,
> + FUSE_DAX_MOUNT_NEVER,
> +};
How about getting rid of "MOUNT" and just do.
FUSE_DAX_INODE,
FUSE_DAX_ALWAYS,
FUSE_DAX_NEVER,
> +
> struct fuse_fs_context {
> int fd;
> unsigned int rootmode;
> @@ -503,7 +509,7 @@ struct fuse_fs_context {
> bool no_control:1;
> bool no_force_umount:1;
> bool legacy_opts_show:1;
> - bool dax:1;
> + unsigned int dax;
enum fuse_dax_mode dax_mode;
> unsigned int max_read;
> unsigned int blksize;
> const char *subtype;
> @@ -1242,7 +1248,8 @@ ssize_t fuse_dax_read_iter(struct kiocb *iocb, struct
iov_iter *to);
> ssize_t fuse_dax_write_iter(struct kiocb *iocb, struct iov_iter *from);
> int fuse_dax_mmap(struct file *file, struct vm_area_struct *vma);
> int fuse_dax_break_layouts(struct inode *inode, u64 dmap_start, u64
dmap_end);
> -int fuse_dax_conn_alloc(struct fuse_conn *fc, struct dax_device *dax_dev);
> +int fuse_dax_conn_alloc(struct fuse_conn *fc, unsigned int mode,
^^
enum fuse_dax_mode dax_mode> + struct dax_device *dax_dev);
> void fuse_dax_conn_free(struct fuse_conn *fc);
> bool fuse_dax_inode_alloc(struct super_block *sb, struct fuse_inode *fi);
> void fuse_dax_inode_init(struct inode *inode);
> diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
> index b9beb39a4a18..f6b46395edb2 100644
> --- a/fs/fuse/inode.c
> +++ b/fs/fuse/inode.c
> @@ -1434,7 +1434,7 @@ int fuse_fill_super_common(struct super_block *sb,
struct fuse_fs_context *ctx)
> sb->s_subtype = ctx->subtype;
> ctx->subtype = NULL;
> if (IS_ENABLED(CONFIG_FUSE_DAX)) {
> - err = fuse_dax_conn_alloc(fc, ctx->dax_dev);
> + err = fuse_dax_conn_alloc(fc, ctx->dax, ctx->dax_dev);
> if (err)
> goto err;
> }
> diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c
> index 8f52cdaa8445..561f711d1945 100644
> --- a/fs/fuse/virtio_fs.c
> +++ b/fs/fuse/virtio_fs.c
> @@ -88,12 +88,21 @@ struct virtio_fs_req_work {
> static int virtio_fs_enqueue_req(struct virtio_fs_vq *fsvq,
> struct fuse_req *req, bool in_flight);
>
> +static const struct constant_table dax_param_enums[] = {
> + {"inode", FUSE_DAX_MOUNT_INODE },
> + {"always", FUSE_DAX_MOUNT_ALWAYS },
> + {"never", FUSE_DAX_MOUNT_NEVER },
> + {}
> +};
> +
> enum {
> OPT_DAX,
> + OPT_DAX_ENUM,
> };
>
> static const struct fs_parameter_spec virtio_fs_parameters[] = {
> fsparam_flag("dax", OPT_DAX),
> + fsparam_enum("dax", OPT_DAX_ENUM, dax_param_enums),
> {}
> };
>
> @@ -110,7 +119,10 @@ static int virtio_fs_parse_param(struct fs_context
*fc,
>
> switch (opt) {
> case OPT_DAX:
> - ctx->dax = 1;
> + ctx->dax = FUSE_DAX_MOUNT_ALWAYS;
> + break;
> + case OPT_DAX_ENUM:
> + ctx->dax = result.uint_32;
Do we want to check here if result.uint_32 has one of the allowed values.
FUSE_DAX_MOUNT_INODE, FUSE_DAX_MOUNT_ALWAYS or FUSE_DAX_MOUNT_NEVER. Or
VFS has already taken care of that?
Vivek
> break;
> default:
> return -EINVAL;
> @@ -1326,7 +1338,7 @@ static int virtio_fs_fill_super(struct super_block
*sb, struct fs_context *fsc)
>
> /* virtiofs allocates and installs its own fuse devices */
> ctx->fudptr = NULL;
> - if (ctx->dax) {
> + if (ctx->dax != FUSE_DAX_MOUNT_NEVER) {
> if (!fs->dax_dev) {
> err = -EINVAL;
> pr_err("virtio-fs: dax can't be enabled as filesystem"
> --
> 2.27.0
>