@@ -107,11 +107,13 @@ static const struct constant_table dax_param_enums[] = {
enum {
OPT_DAX,
OPT_DAX_ENUM,
+ OPT_FILE,
};
static const struct fs_parameter_spec virtio_fs_parameters[] = {
fsparam_flag("dax", OPT_DAX),
fsparam_enum("dax", OPT_DAX_ENUM, dax_param_enums),
+ fsparam_flag("file", OPT_FILE),
{}
};
@@ -133,6 +135,10 @@ static int virtio_fs_parse_param(struct fs_context *fsc,
case OPT_DAX_ENUM:
ctx->dax_mode = result.uint_32;
break;
+ case OPT_FILE:
+ ctx->rootmode = S_IFREG;
+ ctx->rootmode_present = true;
+ break;
default:
return -EINVAL;
}
@@ -1401,7 +1407,8 @@ static const struct fuse_iqueue_ops virtio_fs_fiq_ops = {
static inline void virtio_fs_ctx_set_defaults(struct fuse_fs_context *ctx)
{
- ctx->rootmode = S_IFDIR;
+ if (!ctx->rootmode_present)
+ ctx->rootmode = S_IFDIR;
ctx->default_permissions = 1;
ctx->allow_other = 1;
ctx->max_read = UINT_MAX;
This new option allows mounting filesystems whose root node is a regular file instead of a directory. FUSE itself has the more generic 'rootmode' option, which theoretically allows mounting filesystems with an even greater variety of root node modes. There are two reasons why we do not let virtio-fs provide that same option: First, with FUSE, this option is supposed to be set automatically by e.g. the fusermount helper program to match the root node's mode, no user involvement necessary. It is easy for fusermount to stat() the mount point (whose mode must match the filesystem's root node mode) and fill the 'rootmode' option appropriately. In the case of virtio-fs, however, mounting is often done manually by the user, there is no helper program; and I as a user find the simple '-o file' preferable over the more cryptic '-o rootmode=0100000'. Second, inode modes other than S_IFDIR and S_IFREG have limited use with virtio-fs anyway: - Device files are host-specific, so passing them via virtio-fs from host to guest (or between different guests) seems rarely useful, - FIFOs and Unix domain sockets currently do not allow communication between guest and host (or between different guests), which is really the only reason why they would be used as virtio-fs filesystem root nodes, - and symlinks in general do not make much sense as filesystem root nodes. The more generic 'rootmode' option is therefore not very useful for virtio-fs, while being harder to use. Signed-off-by: Hanna Czenczek <hreitz@redhat.com> --- fs/fuse/virtio_fs.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)