diff options
Diffstat (limited to 'fs/fuse/inode.c')
| -rw-r--r-- | fs/fuse/inode.c | 55 |
1 files changed, 49 insertions, 6 deletions
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 516ea2979a90..3a5d88878335 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -111,6 +111,9 @@ static struct inode *fuse_alloc_inode(struct super_block *sb) if (IS_ENABLED(CONFIG_FUSE_DAX) && !fuse_dax_inode_alloc(sb, fi)) goto out_free_forget; + if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH)) + fuse_inode_backing_set(fi, NULL); + return &fi->inode; out_free_forget: @@ -129,6 +132,9 @@ static void fuse_free_inode(struct inode *inode) #ifdef CONFIG_FUSE_DAX kfree(fi->dax); #endif + if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH)) + fuse_backing_put(fuse_inode_backing(fi)); + kmem_cache_free(fuse_inode_cachep, fi); } @@ -469,8 +475,11 @@ retry: } else if (fuse_stale_inode(inode, generation, attr)) { /* nodeid was reused, any I/O on the old inode should fail */ fuse_make_bad(inode); - iput(inode); - goto retry; + if (inode != d_inode(sb->s_root)) { + remove_inode_hash(inode); + iput(inode); + goto retry; + } } fi = get_fuse_inode(inode); spin_lock(&fi->lock); @@ -924,6 +933,9 @@ void fuse_conn_init(struct fuse_conn *fc, struct fuse_mount *fm, fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ; fc->max_pages_limit = FUSE_MAX_MAX_PAGES; + if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH)) + fuse_backing_files_init(fc); + INIT_LIST_HEAD(&fc->mounts); list_add(&fm->fc_entry, &fc->mounts); fm->fc = fc; @@ -954,6 +966,8 @@ void fuse_conn_put(struct fuse_conn *fc) WARN_ON(atomic_read(&bucket->count) != 1); kfree(bucket); } + if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH)) + fuse_backing_files_free(fc); call_rcu(&fc->rcu, delayed_release); } } @@ -974,7 +988,7 @@ static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode) attr.mode = mode; attr.ino = FUSE_ROOT_ID; attr.nlink = 1; - return fuse_iget(sb, 1, 0, &attr, 0, 0); + return fuse_iget(sb, FUSE_ROOT_ID, 0, &attr, 0, 0); } struct fuse_inode_handle { @@ -1117,6 +1131,11 @@ static struct dentry *fuse_get_parent(struct dentry *child) return parent; } +/* only for fid encoding; no support for file handle */ +static const struct export_operations fuse_export_fid_operations = { + .encode_fh = fuse_encode_fh, +}; + static const struct export_operations fuse_export_operations = { .fh_to_dentry = fuse_fh_to_dentry, .fh_to_parent = fuse_fh_to_parent, @@ -1291,6 +1310,26 @@ static void process_init_reply(struct fuse_mount *fm, struct fuse_args *args, fc->create_supp_group = 1; if (flags & FUSE_DIRECT_IO_ALLOW_MMAP) fc->direct_io_allow_mmap = 1; + /* + * max_stack_depth is the max stack depth of FUSE fs, + * so it has to be at least 1 to support passthrough + * to backing files. + * + * with max_stack_depth > 1, the backing files can be + * on a stacked fs (e.g. overlayfs) themselves and with + * max_stack_depth == 1, FUSE fs can be stacked as the + * underlying fs of a stacked fs (e.g. overlayfs). + */ + if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH) && + (flags & FUSE_PASSTHROUGH) && + arg->max_stack_depth > 0 && + arg->max_stack_depth <= FILESYSTEM_MAX_STACK_DEPTH) { + fc->passthrough = 1; + fc->max_stack_depth = arg->max_stack_depth; + fm->sb->s_stack_depth = arg->max_stack_depth; + } + if (flags & FUSE_NO_EXPORT_SUPPORT) + fm->sb->s_export_op = &fuse_export_fid_operations; } else { ra_pages = fc->max_read / PAGE_SIZE; fc->no_lock = 1; @@ -1337,7 +1376,8 @@ void fuse_send_init(struct fuse_mount *fm) FUSE_NO_OPENDIR_SUPPORT | FUSE_EXPLICIT_INVAL_DATA | FUSE_HANDLE_KILLPRIV_V2 | FUSE_SETXATTR_EXT | FUSE_INIT_EXT | FUSE_SECURITY_CTX | FUSE_CREATE_SUPP_GROUP | - FUSE_HAS_EXPIRE_ONLY | FUSE_DIRECT_IO_ALLOW_MMAP; + FUSE_HAS_EXPIRE_ONLY | FUSE_DIRECT_IO_ALLOW_MMAP | + FUSE_NO_EXPORT_SUPPORT | FUSE_HAS_RESEND; #ifdef CONFIG_FUSE_DAX if (fm->fc->dax) flags |= FUSE_MAP_ALIGNMENT; @@ -1346,6 +1386,8 @@ void fuse_send_init(struct fuse_mount *fm) #endif if (fm->fc->auto_submounts) flags |= FUSE_SUBMOUNTS; + if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH)) + flags |= FUSE_PASSTHROUGH; ia->in.flags = flags; ia->in.flags2 = flags >> 32; @@ -1496,8 +1538,8 @@ static void fuse_fill_attr_from_inode(struct fuse_attr *attr, .ctimensec = ctime.tv_nsec, .mode = fi->inode.i_mode, .nlink = fi->inode.i_nlink, - .uid = fi->inode.i_uid.val, - .gid = fi->inode.i_gid.val, + .uid = __kuid_val(fi->inode.i_uid), + .gid = __kgid_val(fi->inode.i_gid), .rdev = fi->inode.i_rdev, .blksize = 1u << fi->inode.i_blkbits, }; @@ -1534,6 +1576,7 @@ static int fuse_fill_super_submount(struct super_block *sb, sb->s_bdi = bdi_get(parent_sb->s_bdi); sb->s_xattr = parent_sb->s_xattr; + sb->s_export_op = parent_sb->s_export_op; sb->s_time_gran = parent_sb->s_time_gran; sb->s_blocksize = parent_sb->s_blocksize; sb->s_blocksize_bits = parent_sb->s_blocksize_bits; |