Add a mount option to allow using dax with virtio_fs. Signed-off-by: Vivek Goyal <vgoyal@xxxxxxxxxx> --- fs/fuse/fuse_i.h | 7 ++++ fs/fuse/inode.c | 3 ++ fs/fuse/virtio_fs.c | 82 +++++++++++++++++++++++++++++++++++++-------- 3 files changed, 78 insertions(+), 14 deletions(-) diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index cf5e675100ec..04fdd7c41bd1 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -486,10 +486,14 @@ struct fuse_fs_context { bool destroy:1; bool no_control:1; bool no_force_umount:1; + bool dax:1; unsigned int max_read; unsigned int blksize; const char *subtype; + /* DAX device, may be NULL */ + struct dax_device *dax_dev; + /* fuse_dev pointer to fill in, should contain NULL on entry */ void **fudptr; }; @@ -761,6 +765,9 @@ struct fuse_conn { /** List of device instances belonging to this connection */ struct list_head devices; + + /** DAX device, non-NULL if DAX is supported */ + struct dax_device *dax_dev; }; static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb) diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 2ac5713c4c32..beac337ccc10 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -589,6 +589,8 @@ static int fuse_show_options(struct seq_file *m, struct dentry *root) seq_printf(m, ",max_read=%u", fc->max_read); if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE) seq_printf(m, ",blksize=%lu", sb->s_blocksize); + if (fc->dax_dev) + seq_printf(m, ",dax"); return 0; } @@ -1207,6 +1209,7 @@ int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx) fc->destroy = ctx->destroy; fc->no_control = ctx->no_control; fc->no_force_umount = ctx->no_force_umount; + fc->dax_dev = ctx->dax_dev; err = -ENOMEM; root = fuse_get_root_inode(sb, ctx->rootmode); diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c index 0fd3b5cecc5f..741cad4abad8 100644 --- a/fs/fuse/virtio_fs.c +++ b/fs/fuse/virtio_fs.c @@ -13,6 +13,7 @@ #include <linux/virtio_fs.h> #include <linux/delay.h> #include <linux/fs_context.h> +#include <linux/fs_parser.h> #include <linux/highmem.h> #include <linux/uio.h> #include "fuse_i.h" @@ -81,6 +82,45 @@ struct virtio_fs_req_work { static int virtio_fs_enqueue_req(struct virtio_fs_vq *fsvq, struct fuse_req *req, bool in_flight); +enum { + OPT_DAX, +}; + +static const struct fs_parameter_spec virtio_fs_parameters[] = { + fsparam_flag ("dax", OPT_DAX), + {} +}; + +static int virtio_fs_parse_param(struct fs_context *fc, + struct fs_parameter *param) +{ + struct fs_parse_result result; + struct fuse_fs_context *ctx = fc->fs_private; + int opt; + + opt = fs_parse(fc, virtio_fs_parameters, param, &result); + if (opt < 0) + return opt; + + switch (opt) { + case OPT_DAX: + ctx->dax = 1; + break; + default: + return -EINVAL; + } + + return 0; +} + +static void virtio_fs_free_fc(struct fs_context *fc) +{ + struct fuse_fs_context *ctx = fc->fs_private; + + if (ctx) + kfree(ctx); +} + static inline struct virtio_fs_vq *vq_to_fsvq(struct virtqueue *vq) { struct virtio_fs *fs = vq->vdev->priv; @@ -1220,23 +1260,27 @@ static const struct fuse_iqueue_ops virtio_fs_fiq_ops = { .release = virtio_fs_fiq_release, }; -static int virtio_fs_fill_super(struct super_block *sb) +static inline void virtio_fs_ctx_set_defaults(struct fuse_fs_context *ctx) +{ + ctx->rootmode = S_IFDIR; + ctx->default_permissions = 1; + ctx->allow_other = 1; + ctx->max_read = UINT_MAX; + ctx->blksize = 512; + ctx->destroy = true; + ctx->no_control = true; + ctx->no_force_umount = true; +} + +static int virtio_fs_fill_super(struct super_block *sb, struct fs_context *fsc) { struct fuse_conn *fc = get_fuse_conn_super(sb); struct virtio_fs *fs = fc->iq.priv; + struct fuse_fs_context *ctx = fsc->fs_private; unsigned int i; int err; - struct fuse_fs_context ctx = { - .rootmode = S_IFDIR, - .default_permissions = 1, - .allow_other = 1, - .max_read = UINT_MAX, - .blksize = 512, - .destroy = true, - .no_control = true, - .no_force_umount = true, - }; + virtio_fs_ctx_set_defaults(ctx); mutex_lock(&virtio_fs_mutex); /* After holding mutex, make sure virtiofs device is still there. @@ -1260,8 +1304,10 @@ static int virtio_fs_fill_super(struct super_block *sb) } /* virtiofs allocates and installs its own fuse devices */ - ctx.fudptr = NULL; - err = fuse_fill_super_common(sb, &ctx); + ctx->fudptr = NULL; + if (ctx->dax) + ctx->dax_dev = fs->dax_dev; + err = fuse_fill_super_common(sb, ctx); if (err < 0) goto err_free_fuse_devs; @@ -1372,7 +1418,7 @@ static int virtio_fs_get_tree(struct fs_context *fsc) return PTR_ERR(sb); if (!sb->s_root) { - err = virtio_fs_fill_super(sb); + err = virtio_fs_fill_super(sb, fsc); if (err) { deactivate_locked_super(sb); return err; @@ -1387,11 +1433,19 @@ static int virtio_fs_get_tree(struct fs_context *fsc) } static const struct fs_context_operations virtio_fs_context_ops = { + .free = virtio_fs_free_fc, + .parse_param = virtio_fs_parse_param, .get_tree = virtio_fs_get_tree, }; static int virtio_fs_init_fs_context(struct fs_context *fsc) { + struct fuse_fs_context *ctx; + + ctx = kzalloc(sizeof(struct fuse_fs_context), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + fsc->fs_private = ctx; fsc->ops = &virtio_fs_context_ops; return 0; } -- 2.25.4