fuse

4 files changed, 601 insertions, 1 deletions

diff --git a/Makefile b/Makefile
index c6daadc8..2ec19e7f 100644
--- a/Makefile
+++ b/Makefile
@@ -12,6 +12,7 @@ CFLAGS+=-std=gnu89 -O2 -g -MMD -Wall				\
 	-D_LGPL_SOURCE						\
 	-DRCU_MEMBARRIER					\
 	-DZSTD_STATIC_LINKING_ONLY				\
+	-DFUSE_USE_VERSION=32					\
 	-DNO_BCACHEFS_CHARDEV					\
 	-DNO_BCACHEFS_FS					\
 	-DNO_BCACHEFS_SYSFS					\
@@ -36,7 +37,7 @@ ifdef D
 	CFLAGS+=-DCONFIG_BCACHEFS_DEBUG=y
 endif
 
-PKGCONFIG_LIBS="blkid uuid liburcu libsodium zlib liblz4 libzstd"
+PKGCONFIG_LIBS="blkid uuid liburcu libsodium zlib liblz4 libzstd fuse3"
 
 PKGCONFIG_CFLAGS:=$(shell $(PKG_CONFIG) --cflags $(PKGCONFIG_LIBS))
 ifeq (,$(PKGCONFIG_CFLAGS))
diff --git a/bcachefs.c b/bcachefs.c
index 9c503e00..8840d516 100644
--- a/bcachefs.c
+++ b/bcachefs.c
@@ -203,6 +203,9 @@ int main(int argc, char *argv[])
 	if (!strcmp(cmd, "setattr"))
 		return cmd_setattr(argc, argv);
 
+	if (!strcmp(cmd, "fusemount"))
+		return cmd_fusemount(argc, argv);
+
 	if (!strcmp(cmd, "--help")) {
 		usage();
 		return 0;
diff --git a/cmd_fusemount.c b/cmd_fusemount.c
new file mode 100644
index 00000000..6f9a9be8
--- /dev/null
+++ b/cmd_fusemount.c
@@ -0,0 +1,594 @@
+#include <errno.h>
+#include <float.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <sys/statvfs.h>
+
+#include <fuse_lowlevel.h>
+
+#include "cmds.h"
+#include "libbcachefs.h"
+#include "tools-util.h"
+
+#include "libbcachefs/bcachefs.h"
+#include "libbcachefs/btree_iter.h"
+#include "libbcachefs/buckets.h"
+#include "libbcachefs/dirent.h"
+#include "libbcachefs/error.h"
+#include "libbcachefs/fs-common.h"
+#include "libbcachefs/inode.h"
+#include "libbcachefs/opts.h"
+#include "libbcachefs/super.h"
+
+/* mode_to_type(): */
+#include "libbcachefs/fs.h"
+
+#include <linux/dcache.h>
+
+/* XXX cut and pasted from fsck.c */
+#define QSTR(n) { { { .len = strlen(n) } }, .name = n }
+
+static inline u64 map_root_ino(u64 ino)
+{
+	return ino == 1 ? 4096 : ino;
+}
+
+static inline u64 unmap_root_ino(u64 ino)
+{
+	return ino == 4096 ? 1 : ino;
+}
+
+static struct stat inode_to_stat(struct bch_fs *c,
+				 struct bch_inode_unpacked *bi)
+{
+	return (struct stat) {
+		.st_size	= bi->bi_size,
+		.st_mode	= bi->bi_mode,
+		.st_uid		= bi->bi_uid,
+		.st_gid		= bi->bi_gid,
+		.st_nlink	= bch2_inode_nlink_get(bi),
+		.st_rdev	= bi->bi_dev,
+		.st_blksize	= block_bytes(c),
+		.st_blocks	= bi->bi_sectors,
+		.st_atim	= bch2_time_to_timespec(c, bi->bi_atime),
+		.st_mtim	= bch2_time_to_timespec(c, bi->bi_mtime),
+		.st_ctim	= bch2_time_to_timespec(c, bi->bi_ctime),
+	};
+}
+
+static struct fuse_entry_param inode_to_entry(struct bch_fs *c,
+					      struct bch_inode_unpacked *bi)
+{
+	return (struct fuse_entry_param) {
+		.ino		= bi->bi_inum,
+		.generation	= bi->bi_generation,
+		.attr		= inode_to_stat(c, bi),
+		.attr_timeout	= DBL_MAX,
+		.entry_timeout	= DBL_MAX,
+	};
+}
+
+static void bcachefs_fuse_destroy(void *arg)
+{
+	struct bch_fs *c = arg;
+
+	bch2_fs_stop(c);
+}
+
+static void bcachefs_fuse_lookup(fuse_req_t req, fuse_ino_t dir,
+				 const char *name)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+	struct bch_inode_unpacked bi;
+	struct qstr qstr = QSTR(name);
+	u64 inum;
+	int ret;
+
+	dir = map_root_ino(dir);
+
+	pr_info("dir %llu name %s", (u64) dir, name);
+
+	inum = bch2_dirent_lookup(c, dir, &qstr);
+	if (!inum) {
+		ret = -ENOENT;
+		goto err;
+	}
+
+	ret = bch2_inode_find_by_inum(c, inum, &bi);
+	if (ret)
+		goto err;
+
+	bi.bi_inum = unmap_root_ino(bi.bi_inum);
+
+	struct fuse_entry_param e = inode_to_entry(c, &bi);
+	fuse_reply_entry(req, &e);
+	return;
+err:
+	fuse_reply_err(req, -ret);
+}
+
+static void bcachefs_fuse_getattr(fuse_req_t req, fuse_ino_t inum,
+				  struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+	struct bch_inode_unpacked bi;
+	struct stat attr;
+	int ret;
+
+	inum = map_root_ino(inum);
+
+	pr_info("inum %llu", (u64) inum);
+
+	ret = bch2_inode_find_by_inum(c, inum, &bi);
+	if (ret) {
+		fuse_reply_err(req, -ret);
+		return;
+	}
+
+	bi.bi_inum = unmap_root_ino(bi.bi_inum);
+
+	attr = inode_to_stat(c, &bi);
+	fuse_reply_attr(req, &attr, DBL_MAX);
+}
+
+static void bcachefs_fuse_setattr(fuse_req_t req, fuse_ino_t inum,
+				  struct stat *attr, int to_set,
+				  struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+	struct bch_inode_unpacked inode_u;
+	struct btree_trans trans;
+	struct btree_iter *iter;
+	u64 now;
+	int ret;
+
+	inum = map_root_ino(inum);
+
+	bch2_trans_init(&trans, c, 0, 0);
+retry:
+	bch2_trans_begin(&trans);
+	now = bch2_current_time(c);
+
+	iter = bch2_inode_peek(&trans, &inode_u, inum, BTREE_ITER_INTENT);
+	ret = PTR_ERR_OR_ZERO(iter);
+	if (ret)
+		goto err;
+
+	if (to_set & FUSE_SET_ATTR_MODE)
+		inode_u.bi_mode	= attr->st_mode;
+	if (to_set & FUSE_SET_ATTR_UID)
+		inode_u.bi_uid	= attr->st_uid;
+	if (to_set & FUSE_SET_ATTR_GID)
+		inode_u.bi_gid	= attr->st_gid;
+	if (to_set & FUSE_SET_ATTR_SIZE)
+		inode_u.bi_size	= attr->st_size;
+	if (to_set & FUSE_SET_ATTR_ATIME)
+		inode_u.bi_atime = timespec_to_bch2_time(c, attr->st_atim);
+	if (to_set & FUSE_SET_ATTR_MTIME)
+		inode_u.bi_mtime = timespec_to_bch2_time(c, attr->st_mtim);
+	if (to_set & FUSE_SET_ATTR_ATIME_NOW)
+		inode_u.bi_atime = now;
+	if (to_set & FUSE_SET_ATTR_MTIME_NOW)
+		inode_u.bi_mtime = now;
+
+	ret   = bch2_inode_write(&trans, iter, &inode_u) ?:
+		bch2_trans_commit(&trans, NULL, NULL,
+				  BTREE_INSERT_ATOMIC|
+				  BTREE_INSERT_NOFAIL);
+err:
+	if (ret == -EINTR)
+		goto retry;
+
+	bch2_trans_exit(&trans);
+
+	if (!ret) {
+		*attr = inode_to_stat(c, &inode_u);
+		fuse_reply_attr(req, attr, DBL_MAX);
+	} else {
+		fuse_reply_err(req, -ret);
+	}
+}
+
+static void bcachefs_fuse_readlink(fuse_req_t req, fuse_ino_t inum)
+{
+	//struct bch_fs *c = fuse_req_userdata(req);
+
+	//char *link = malloc();
+
+	//fuse_reply_readlink(req, link);
+}
+
+static int do_create(struct bch_fs *c, u64 dir,
+		     const char *name, mode_t mode, dev_t rdev,
+		     struct bch_inode_unpacked *new_inode)
+{
+	struct qstr qstr = QSTR(name);
+	struct bch_inode_unpacked dir_u;
+
+	dir = map_root_ino(dir);
+
+	bch2_inode_init_early(c, new_inode);
+
+	return bch2_trans_do(c, NULL, 0,
+			bch2_create_trans(&trans,
+				dir, &dir_u,
+				new_inode, &qstr,
+				0, 0, mode, rdev, NULL, NULL));
+}
+
+static void bcachefs_fuse_mknod(fuse_req_t req, fuse_ino_t dir,
+				const char *name, mode_t mode,
+				dev_t rdev)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+	struct bch_inode_unpacked new_inode;
+	int ret;
+
+	ret = do_create(c, dir, name, mode, rdev, &new_inode);
+	if (ret)
+		goto err;
+
+	struct fuse_entry_param e = inode_to_entry(c, &new_inode);
+	fuse_reply_entry(req, &e);
+	return;
+err:
+	fuse_reply_err(req, -ret);
+}
+
+static void bcachefs_fuse_mkdir(fuse_req_t req, fuse_ino_t dir,
+				const char *name, mode_t mode)
+{
+	bcachefs_fuse_mknod(req, dir, name, mode, 0);
+}
+
+static void bcachefs_fuse_unlink(fuse_req_t req, fuse_ino_t dir,
+				 const char *name)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+	struct bch_inode_unpacked dir_u, inode_u;
+	struct qstr qstr = QSTR(name);
+	int ret;
+
+	dir = map_root_ino(dir);
+
+	ret = bch2_trans_do(c, NULL, BTREE_INSERT_ATOMIC|BTREE_INSERT_NOFAIL,
+			    bch2_unlink_trans(&trans, dir, &dir_u,
+					      &inode_u, &qstr));
+
+	fuse_reply_err(req, -ret);
+}
+
+static void bcachefs_fuse_rmdir(fuse_req_t req, fuse_ino_t dir,
+				const char *name)
+{
+	dir = map_root_ino(dir);
+
+	bcachefs_fuse_unlink(req, dir, name);
+}
+
+#if 0
+static void bcachefs_fuse_symlink(fuse_req_t req, const char *link,
+				  fuse_ino_t parent, const char *name)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+#endif
+
+static void bcachefs_fuse_rename(fuse_req_t req,
+				 fuse_ino_t src_dir, const char *srcname,
+				 fuse_ino_t dst_dir, const char *dstname,
+				 unsigned flags)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+	struct bch_inode_unpacked dst_dir_u, src_dir_u;
+	struct bch_inode_unpacked src_inode_u, dst_inode_u;
+	struct qstr dst_name = QSTR(srcname);
+	struct qstr src_name = QSTR(dstname);
+	int ret;
+
+	src_dir = map_root_ino(src_dir);
+	dst_dir = map_root_ino(dst_dir);
+
+	/* XXX handle overwrites */
+	ret = bch2_trans_do(c, NULL, BTREE_INSERT_ATOMIC,
+		bch2_rename_trans(&trans,
+				  src_dir, &src_dir_u,
+				  dst_dir, &dst_dir_u,
+				  &src_inode_u, &dst_inode_u,
+				  &src_name, &dst_name,
+				  BCH_RENAME));
+
+	fuse_reply_err(req, -ret);
+}
+
+static void bcachefs_fuse_link(fuse_req_t req, fuse_ino_t inum,
+			       fuse_ino_t newparent, const char *newname)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+	struct bch_inode_unpacked inode_u;
+	struct qstr qstr = QSTR(newname);
+	int ret;
+
+	ret = bch2_trans_do(c, NULL, BTREE_INSERT_ATOMIC,
+			    bch2_link_trans(&trans, newparent,
+					    inum, &inode_u, &qstr));
+
+	if (!ret) {
+		struct fuse_entry_param e = inode_to_entry(c, &inode_u);
+		fuse_reply_entry(req, &e);
+	} else {
+		fuse_reply_err(req, -ret);
+	}
+}
+
+#if 0
+static void bcachefs_fuse_open(fuse_req_t req, fuse_ino_t inum,
+			       struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+
+static void bcachefs_fuse_read(fuse_req_t req, fuse_ino_t inum,
+			       size_t size, off_t off,
+			       struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+
+static void bcachefs_fuse_flush(fuse_req_t req, fuse_ino_t inum,
+				struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+
+static void bcachefs_fuse_release(fuse_req_t req, fuse_ino_t inum,
+				  struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+
+static void bcachefs_fuse_fsync(fuse_req_t req, fuse_ino_t inum, int datasync,
+				struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+
+static void bcachefs_fuse_opendir(fuse_req_t req, fuse_ino_t inum,
+				  struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+#endif
+
+struct fuse_dir_context {
+	struct dir_context	ctx;
+	fuse_req_t		req;
+	char			*buf;
+	size_t			bufsize;
+};
+
+static int fuse_filldir(struct dir_context *_ctx,
+			const char *name, int namelen,
+			loff_t pos, u64 dir, unsigned type)
+{
+	struct fuse_dir_context *ctx =
+		container_of(_ctx, struct fuse_dir_context, ctx);
+
+	struct stat statbuf = {
+		.st_ino		= map_root_ino(dir),
+		.st_mode	= type << 12,
+	};
+
+	size_t len = fuse_add_direntry(ctx->req,
+				       ctx->buf,
+				       ctx->bufsize,
+				       name,
+				       &statbuf,
+				       pos + 1);
+
+	if (len > ctx->bufsize)
+		return 0;
+
+	ctx->buf	+= len;
+	ctx->bufsize	-= len;
+	return 1;
+}
+
+static void bcachefs_fuse_readdir(fuse_req_t req, fuse_ino_t dir,
+				  size_t size, off_t off,
+				  struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+	char buf[4096];
+	struct fuse_dir_context ctx = {
+		.ctx.actor	= fuse_filldir,
+		.ctx.pos	= off,
+		.req		= req,
+		.buf		= buf,
+		.bufsize	= sizeof(buf),
+	};
+	int ret;
+
+	dir = map_root_ino(dir);
+
+	ret = bch2_readdir(c, dir, &ctx.ctx);
+	if (!ret) {
+		fuse_reply_buf(req, buf, ctx.buf - buf);
+	} else {
+		fuse_reply_err(req, -ret);
+	}
+}
+
+#if 0
+static void bcachefs_fuse_releasedir(fuse_req_t req, fuse_ino_t inum,
+				     struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+
+static void bcachefs_fuse_fsyncdir(fuse_req_t req, fuse_ino_t inum, int datasync,
+				   struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+#endif
+
+static void bcachefs_fuse_statfs(fuse_req_t req, fuse_ino_t inum)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+	struct bch_fs_usage_short usage = bch2_fs_usage_read_short(c);
+	unsigned shift = c->block_bits;
+	struct statvfs statbuf = {
+		.f_bsize	= block_bytes(c),
+		.f_frsize	= block_bytes(c),
+		.f_blocks	= usage.capacity >> shift,
+		.f_bfree	= (usage.capacity - usage.used) >> shift,
+		//.f_bavail	= statbuf.f_bfree,
+		.f_files	= usage.nr_inodes,
+		.f_ffree	= U64_MAX,
+		.f_namemax	= BCH_NAME_MAX,
+	};
+
+	fuse_reply_statfs(req, &statbuf);
+}
+
+#if 0
+static void bcachefs_fuse_setxattr(fuse_req_t req, fuse_ino_t inum,
+				   const char *name, const char *value,
+				   size_t size, int flags)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+
+static void bcachefs_fuse_getxattr(fuse_req_t req, fuse_ino_t inum,
+				   const char *name, size_t size)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+
+	fuse_reply_xattr(req, );
+}
+
+static void bcachefs_fuse_listxattr(fuse_req_t req, fuse_ino_t inum, size_t size)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+
+static void bcachefs_fuse_removexattr(fuse_req_t req, fuse_ino_t inum,
+				      const char *name)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+#endif
+
+static void bcachefs_fuse_create(fuse_req_t req, fuse_ino_t dir,
+				 const char *name, mode_t mode,
+				 struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+	struct bch_inode_unpacked new_inode;
+	int ret;
+
+	ret = do_create(c, dir, name, mode, 0, &new_inode);
+	if (ret)
+		goto err;
+
+	struct fuse_entry_param e = inode_to_entry(c, &new_inode);
+	fuse_reply_create(req, &e, fi);
+	return;
+err:
+	fuse_reply_err(req, -ret);
+
+}
+
+#if 0
+static void bcachefs_fuse_write_buf(fuse_req_t req, fuse_ino_t inum,
+				    struct fuse_bufvec *bufv, off_t off,
+				    struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+
+static void bcachefs_fuse_fallocate(fuse_req_t req, fuse_ino_t inum, int mode,
+				    off_t offset, off_t length,
+				    struct fuse_file_info *fi)
+{
+	struct bch_fs *c = fuse_req_userdata(req);
+}
+#endif
+
+static const struct fuse_lowlevel_ops bcachefs_fuse_ops = {
+	.destroy	= bcachefs_fuse_destroy,
+	.lookup		= bcachefs_fuse_lookup,
+	.getattr	= bcachefs_fuse_getattr,
+	.setattr	= bcachefs_fuse_setattr,
+	.readlink	= bcachefs_fuse_readlink,
+	.mknod		= bcachefs_fuse_mknod,
+	.mkdir		= bcachefs_fuse_mkdir,
+	.unlink		= bcachefs_fuse_unlink,
+	.rmdir		= bcachefs_fuse_rmdir,
+	//.symlink	= bcachefs_fuse_symlink,
+	.rename		= bcachefs_fuse_rename,
+	.link		= bcachefs_fuse_link,
+	//.open		= bcachefs_fuse_open,
+	//.read		= bcachefs_fuse_read,
+	//.write	= bcachefs_fuse_write,
+	//.flush	= bcachefs_fuse_flush,
+	//.release	= bcachefs_fuse_release,
+	//.fsync	= bcachefs_fuse_fsync,
+	//.opendir	= bcachefs_fuse_opendir,
+	.readdir	= bcachefs_fuse_readdir,
+	//.releasedir	= bcachefs_fuse_releasedir,
+	//.fsyncdir	= bcachefs_fuse_fsyncdir,
+	.statfs		= bcachefs_fuse_statfs,
+	//.setxattr	= bcachefs_fuse_setxattr,
+	//.getxattr	= bcachefs_fuse_getxattr,
+	//.listxattr	= bcachefs_fuse_listxattr,
+	//.removexattr	= bcachefs_fuse_removexattr,
+	.create		= bcachefs_fuse_create,
+
+	/* posix locks: */
+#if 0
+	.getlk		= bcachefs_fuse_getlk,
+	.setlk		= bcachefs_fuse_setlk,
+#endif
+	//.write_buf	= bcachefs_fuse_write_buf,
+	//.fallocate	= bcachefs_fuse_fallocate,
+
+};
+
+int cmd_fusemount(int argc, char *argv[])
+{
+	struct bch_opts bch_opts = bch2_opts_empty();
+	struct bch_fs *c = NULL;
+
+	c = bch2_fs_open(argv + optind, argc - optind, bch_opts);
+	if (IS_ERR(c))
+		die("error opening %s: %s", argv[optind],
+		    strerror(-PTR_ERR(c)));
+
+	struct fuse_args args = FUSE_ARGS_INIT(argc, argv);
+	struct fuse_cmdline_opts fuse_opts;
+	if (fuse_parse_cmdline(&args, &fuse_opts) < 0)
+		die("fuse_parse_cmdline err: %m");
+
+	struct fuse_session *se =
+		fuse_session_new(&args, &bcachefs_fuse_ops,
+				 sizeof(bcachefs_fuse_ops), c);
+	if (!se)
+		die("fuse_lowlevel_new err: %m");
+
+	if (fuse_set_signal_handlers(se) < 0)
+		die("fuse_set_signal_handlers err: %m");
+
+	if (fuse_session_mount(se, "/home/kent/mnt"))
+		die("fuse_mount err: %m");
+
+	int ret = fuse_session_loop(se);
+
+	fuse_session_unmount(se);
+	fuse_remove_signal_handlers(se);
+	fuse_session_destroy(se);
+	fuse_opt_free_args(&args);
+
+	return ret ? 1 : 0;
+}
diff --git a/cmds.h b/cmds.h
index d64ffeeb..230ad5b0 100644
--- a/cmds.h
+++ b/cmds.h
@@ -47,4 +47,6 @@ int cmd_version(int argc, char *argv[]);
 
 int cmd_setattr(int argc, char *argv[]);
 
+int cmd_fusemount(int argc, char *argv[]);
+
 #endif /* _CMDS_H */