diff mbox series

[18/26] fuse-bpf: Add Rename support

Message ID 20220926231822.994383-19-drosen@google.com (mailing list archive)
State Changes Requested
Delegated to: BPF
Headers show
Series FUSE BPF: A Stacked Filesystem Extension for FUSE | expand

Checks

Context Check Description
bpf/vmtest-bpf-PR fail PR summary
bpf/vmtest-bpf-VM_Test-1 pending Logs for ${{ matrix.test }} on ${{ matrix.arch }} with ${{ matrix.toolchain }}
bpf/vmtest-bpf-VM_Test-2 fail Logs for build for s390x with gcc
bpf/vmtest-bpf-VM_Test-3 fail Logs for build for x86_64 with gcc
bpf/vmtest-bpf-VM_Test-4 fail Logs for build for x86_64 with llvm-16
bpf/vmtest-bpf-VM_Test-5 success Logs for llvm-toolchain
bpf/vmtest-bpf-VM_Test-6 success Logs for set-matrix

Commit Message

Daniel Rosenberg Sept. 26, 2022, 11:18 p.m. UTC 
Signed-off-by: Daniel Rosenberg <drosen@google.com>
Signed-off-by: Paul Lawrence <paullawrence@google.com>
---
 fs/fuse/backing.c | 197 ++++++++++++++++++++++++++++++++++++++++++++++
 fs/fuse/dir.c     |  19 +++++
 fs/fuse/fuse_i.h  |  30 +++++++
 3 files changed, 246 insertions(+)
diff mbox series

Patch

diff --git a/fs/fuse/backing.c b/fs/fuse/backing.c
index 4fd7442c94a1..f4ab92dc8099 100644
--- a/fs/fuse/backing.c
+++ b/fs/fuse/backing.c
@@ -1374,6 +1374,203 @@  int fuse_rmdir_finalize(struct bpf_fuse_args *fa, int *out, struct inode *dir, s
 	return 0;
 }
 
+static int fuse_rename_backing_common(struct inode *olddir,
+				      struct dentry *oldent,
+				      struct inode *newdir,
+				      struct dentry *newent, unsigned int flags)
+{
+	int err = 0;
+	struct path old_backing_path;
+	struct path new_backing_path;
+	struct dentry *old_backing_dir_dentry;
+	struct dentry *old_backing_dentry;
+	struct dentry *new_backing_dir_dentry;
+	struct dentry *new_backing_dentry;
+	struct dentry *trap = NULL;
+	struct inode *target_inode;
+	struct renamedata rd;
+
+	//TODO Actually deal with changing anything that isn't a flag
+	get_fuse_backing_path(oldent, &old_backing_path);
+	if (!old_backing_path.dentry)
+		return -EBADF;
+	get_fuse_backing_path(newent, &new_backing_path);
+	if (!new_backing_path.dentry) {
+		/*
+		 * TODO A file being moved from a backing path to another
+		 * backing path which is not yet instrumented with FUSE-BPF.
+		 * This may be slow and should be substituted with something
+		 * more clever.
+		 */
+		err = -EXDEV;
+		goto put_old_path;
+	}
+	if (new_backing_path.mnt != old_backing_path.mnt) {
+		err = -EXDEV;
+		goto put_new_path;
+	}
+	old_backing_dentry = old_backing_path.dentry;
+	new_backing_dentry = new_backing_path.dentry;
+	old_backing_dir_dentry = dget_parent(old_backing_dentry);
+	new_backing_dir_dentry = dget_parent(new_backing_dentry);
+	target_inode = d_inode(newent);
+
+	trap = lock_rename(old_backing_dir_dentry, new_backing_dir_dentry);
+	if (trap == old_backing_dentry) {
+		err = -EINVAL;
+		goto put_parents;
+	}
+	if (trap == new_backing_dentry) {
+		err = -ENOTEMPTY;
+		goto put_parents;
+	}
+
+	rd = (struct renamedata) {
+		.old_mnt_userns = &init_user_ns,
+		.old_dir = d_inode(old_backing_dir_dentry),
+		.old_dentry = old_backing_dentry,
+		.new_mnt_userns = &init_user_ns,
+		.new_dir = d_inode(new_backing_dir_dentry),
+		.new_dentry = new_backing_dentry,
+		.flags = flags,
+	};
+	err = vfs_rename(&rd);
+	if (err)
+		goto unlock;
+	if (target_inode)
+		fsstack_copy_attr_all(target_inode,
+				get_fuse_inode(target_inode)->backing_inode);
+	fsstack_copy_attr_all(d_inode(oldent), d_inode(old_backing_dentry));
+unlock:
+	unlock_rename(old_backing_dir_dentry, new_backing_dir_dentry);
+put_parents:
+	dput(new_backing_dir_dentry);
+	dput(old_backing_dir_dentry);
+put_new_path:
+	path_put(&new_backing_path);
+put_old_path:
+	path_put(&old_backing_path);
+	return err;
+}
+
+int fuse_rename2_initialize_in(struct bpf_fuse_args *fa, struct fuse_rename2_in *fri,
+			       struct inode *olddir, struct dentry *oldent,
+			       struct inode *newdir, struct dentry *newent,
+			       unsigned int flags)
+{
+	*fri = (struct fuse_rename2_in) {
+		.newdir = get_node_id(newdir),
+		.flags = flags,
+	};
+	*fa = (struct bpf_fuse_args) {
+		.nodeid = get_node_id(olddir),
+		.opcode = FUSE_RENAME2,
+		.in_numargs = 3,
+		.in_args[0] = (struct bpf_fuse_arg) {
+			.size = sizeof(*fri),
+			.value = fri,
+		},
+		.in_args[1] = (struct bpf_fuse_arg) {
+			.size = oldent->d_name.len + 1,
+			.max_size = NAME_MAX + 1,
+			.flags = BPF_FUSE_IMMUTABLE,
+			.value =  (void *) oldent->d_name.name,
+		},
+		.in_args[2] = (struct bpf_fuse_arg) {
+			.size = newent->d_name.len + 1,
+			.max_size = NAME_MAX + 1,
+			.flags = BPF_FUSE_IMMUTABLE,
+			.value =  (void *) newent->d_name.name,
+		},
+	};
+
+	return 0;
+}
+
+int fuse_rename2_initialize_out(struct bpf_fuse_args *fa, struct fuse_rename2_in *fri,
+				struct inode *olddir, struct dentry *oldent,
+				struct inode *newdir, struct dentry *newent,
+				unsigned int flags)
+{
+	return 0;
+}
+
+int fuse_rename2_backing(struct bpf_fuse_args *fa, int *out,
+			 struct inode *olddir, struct dentry *oldent,
+			 struct inode *newdir, struct dentry *newent,
+			 unsigned int flags)
+{
+	const struct fuse_rename2_in *fri = fa->in_args[0].value;
+
+	/* TODO: deal with changing dirs/ents */
+	*out = fuse_rename_backing_common(olddir, oldent, newdir, newent,
+					  fri->flags);
+	return *out;
+}
+
+int fuse_rename2_finalize(struct bpf_fuse_args *fa, int *out,
+			  struct inode *olddir, struct dentry *oldent,
+			  struct inode *newdir, struct dentry *newent,
+			  unsigned int flags)
+{
+	return 0;
+}
+
+int fuse_rename_initialize_in(struct bpf_fuse_args *fa, struct fuse_rename_in *fri,
+			      struct inode *olddir, struct dentry *oldent,
+			      struct inode *newdir, struct dentry *newent)
+{
+	*fri = (struct fuse_rename_in) {
+		.newdir = get_node_id(newdir),
+	};
+	*fa = (struct bpf_fuse_args) {
+		.nodeid = get_node_id(olddir),
+		.opcode = FUSE_RENAME,
+		.in_numargs = 3,
+		.in_args[0] = (struct bpf_fuse_arg) {
+			.size = sizeof(*fri),
+			.value = fri,
+		},
+		.in_args[1] = (struct bpf_fuse_arg) {
+			.size = oldent->d_name.len + 1,
+			.max_size = NAME_MAX + 1,
+			.flags = BPF_FUSE_IMMUTABLE,
+			.value =  (void *) oldent->d_name.name,
+		},
+		.in_args[2] = (struct bpf_fuse_arg) {
+			.size = newent->d_name.len + 1,
+			.max_size = NAME_MAX + 1,
+			.flags = BPF_FUSE_IMMUTABLE,
+			.value =  (void *) newent->d_name.name,
+		},
+	};
+
+	return 0;
+}
+
+int fuse_rename_initialize_out(struct bpf_fuse_args *fa, struct fuse_rename_in *fri,
+			       struct inode *olddir, struct dentry *oldent,
+			       struct inode *newdir, struct dentry *newent)
+{
+	return 0;
+}
+
+int fuse_rename_backing(struct bpf_fuse_args *fa, int *out,
+			struct inode *olddir, struct dentry *oldent,
+			struct inode *newdir, struct dentry *newent)
+{
+	/* TODO: deal with changing dirs/ents */
+	*out = fuse_rename_backing_common(olddir, oldent, newdir, newent, 0);
+	return *out;
+}
+
+int fuse_rename_finalize(struct bpf_fuse_args *fa, int *out,
+			 struct inode *olddir, struct dentry *oldent,
+			 struct inode *newdir, struct dentry *newent)
+{
+	return 0;
+}
+
 int fuse_unlink_initialize_in(struct bpf_fuse_args *fa, struct fuse_dummy_io *dummy,
 			      struct inode *dir, struct dentry *entry)
 {
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index f159b9a6d305..7c9d8540668c 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -1151,6 +1151,16 @@  static int fuse_rename2(struct user_namespace *mnt_userns, struct inode *olddir,
 		return -EINVAL;
 
 	if (flags) {
+#ifdef CONFIG_FUSE_BPF
+		if (fuse_bpf_backing(olddir, struct fuse_rename2_in, err,
+						fuse_rename2_initialize_in,
+						fuse_rename2_initialize_out, fuse_rename2_backing,
+						fuse_rename2_finalize,
+						olddir, oldent, newdir, newent, flags))
+			return err;
+#endif
+
+		/* TODO: how should this go with bpfs involved? */
 		if (fc->no_rename2 || fc->minor < 23)
 			return -EINVAL;
 
@@ -1162,6 +1172,15 @@  static int fuse_rename2(struct user_namespace *mnt_userns, struct inode *olddir,
 			err = -EINVAL;
 		}
 	} else {
+#ifdef CONFIG_FUSE_BPF
+		if (fuse_bpf_backing(olddir, struct fuse_rename_in, err,
+						fuse_rename_initialize_in,
+						fuse_rename_initialize_out, fuse_rename_backing,
+						fuse_rename_finalize,
+						olddir, oldent, newdir, newent))
+			return err;
+#endif
+
 		err = fuse_rename_common(olddir, oldent, newdir, newent, 0,
 					 FUSE_RENAME,
 					 sizeof(struct fuse_rename_in));
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index db769dd0a2e4..6c2f75ae9a5a 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -1465,6 +1465,36 @@  int fuse_rmdir_backing(struct bpf_fuse_args *fa, int *out, struct inode *dir, st
 int fuse_rmdir_finalize(struct bpf_fuse_args *fa, int *out,
 			struct inode *dir, struct dentry *entry);
 
+int fuse_rename2_initialize_in(struct bpf_fuse_args *fa, struct fuse_rename2_in *fri,
+			       struct inode *olddir, struct dentry *oldent,
+			       struct inode *newdir, struct dentry *newent,
+			       unsigned int flags);
+int fuse_rename2_initialize_out(struct bpf_fuse_args *fa, struct fuse_rename2_in *fri,
+				struct inode *olddir, struct dentry *oldent,
+				struct inode *newdir, struct dentry *newent,
+				unsigned int flags);
+int fuse_rename2_backing(struct bpf_fuse_args *fa, int *out,
+			 struct inode *olddir, struct dentry *oldent,
+			 struct inode *newdir, struct dentry *newent,
+			 unsigned int flags);
+int fuse_rename2_finalize(struct bpf_fuse_args *fa, int *out,
+			  struct inode *olddir, struct dentry *oldent,
+			  struct inode *newdir, struct dentry *newent,
+			  unsigned int flags);
+
+int fuse_rename_initialize_in(struct bpf_fuse_args *fa, struct fuse_rename_in *fri,
+			      struct inode *olddir, struct dentry *oldent,
+			      struct inode *newdir, struct dentry *newent);
+int fuse_rename_initialize_out(struct bpf_fuse_args *fa, struct fuse_rename_in *fri,
+			       struct inode *olddir, struct dentry *oldent,
+			       struct inode *newdir, struct dentry *newent);
+int fuse_rename_backing(struct bpf_fuse_args *fa, int *out,
+			struct inode *olddir, struct dentry *oldent,
+			struct inode *newdir, struct dentry *newent);
+int fuse_rename_finalize(struct bpf_fuse_args *fa, int *out,
+			 struct inode *olddir, struct dentry *oldent,
+			 struct inode *newdir, struct dentry *newent);
+
 int fuse_unlink_initialize_in(struct bpf_fuse_args *fa, struct fuse_dummy_io *fmi,
 			      struct inode *dir, struct dentry *entry);
 int fuse_unlink_initialize_out(struct bpf_fuse_args *fa, struct fuse_dummy_io *fmi,