]> git.sesse.net Git - bcachefs-tools-debian/blobdiff - cmd_fusemount.c
Make fuse3 support optional and document.
[bcachefs-tools-debian] / cmd_fusemount.c
index 90d3d869fbf6a4c0492f8026128409cfb039a920..4e4c24cce888b28679841097e49a4961c2e9b70a 100644 (file)
@@ -1,3 +1,5 @@
+#ifdef BCACHEFS_FUSE
+
 #include <errno.h>
 #include <float.h>
 #include <getopt.h>
@@ -44,7 +46,7 @@ static struct stat inode_to_stat(struct bch_fs *c,
                                 struct bch_inode_unpacked *bi)
 {
        return (struct stat) {
-               .st_ino         = bi->bi_inum,
+               .st_ino         = unmap_root_ino(bi->bi_inum),
                .st_size        = bi->bi_size,
                .st_mode        = bi->bi_mode,
                .st_uid         = bi->bi_uid,
@@ -63,7 +65,7 @@ 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,
+               .ino            = unmap_root_ino(bi->bi_inum),
                .generation     = bi->bi_generation,
                .attr           = inode_to_stat(c, bi),
                .attr_timeout   = DBL_MAX,
@@ -98,6 +100,9 @@ static void bcachefs_fuse_lookup(fuse_req_t req, fuse_ino_t dir,
        u64 inum;
        int ret;
 
+       fuse_log(FUSE_LOG_DEBUG, "fuse_lookup(dir=%llu name=%s)\n",
+                dir, name);
+
        dir = map_root_ino(dir);
 
        ret = bch2_inode_find_by_inum(c, dir, &bi);
@@ -110,20 +115,26 @@ static void bcachefs_fuse_lookup(fuse_req_t req, fuse_ino_t dir,
 
        inum = bch2_dirent_lookup(c, dir, &hash_info, &qstr);
        if (!inum) {
-               ret = -ENOENT;
-               goto err;
+               struct fuse_entry_param e = {
+                       .attr_timeout   = DBL_MAX,
+                       .entry_timeout  = DBL_MAX,
+               };
+               fuse_reply_entry(req, &e);
+               return;
        }
 
        ret = bch2_inode_find_by_inum(c, inum, &bi);
        if (ret)
                goto err;
 
-       bi.bi_inum = unmap_root_ino(bi.bi_inum);
+       fuse_log(FUSE_LOG_DEBUG, "fuse_lookup ret(inum=%llu)\n",
+                bi.bi_inum);
 
        struct fuse_entry_param e = inode_to_entry(c, &bi);
        fuse_reply_entry(req, &e);
        return;
 err:
+       fuse_log(FUSE_LOG_DEBUG, "fuse_lookup error %i\n", ret);
        fuse_reply_err(req, -ret);
 }
 
@@ -135,15 +146,19 @@ static void bcachefs_fuse_getattr(fuse_req_t req, fuse_ino_t inum,
        struct stat attr;
        int ret;
 
+       fuse_log(FUSE_LOG_DEBUG, "fuse_getattr(inum=%llu)\n",
+                inum);
+
        inum = map_root_ino(inum);
 
        ret = bch2_inode_find_by_inum(c, inum, &bi);
        if (ret) {
+               fuse_log(FUSE_LOG_DEBUG, "fuse_getattr error %i\n", ret);
                fuse_reply_err(req, -ret);
                return;
        }
 
-       bi.bi_inum = unmap_root_ino(bi.bi_inum);
+       fuse_log(FUSE_LOG_DEBUG, "fuse_getattr success\n");
 
        attr = inode_to_stat(c, &bi);
        fuse_reply_attr(req, &attr, DBL_MAX);
@@ -160,6 +175,9 @@ static void bcachefs_fuse_setattr(fuse_req_t req, fuse_ino_t inum,
        u64 now;
        int ret;
 
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_setattr(%llu, %x)\n",
+                inum, to_set);
+
        inum = map_root_ino(inum);
 
        bch2_trans_init(&trans, c, 0, 0);
@@ -188,6 +206,7 @@ retry:
                inode_u.bi_atime = now;
        if (to_set & FUSE_SET_ATTR_MTIME_NOW)
                inode_u.bi_mtime = now;
+       /* TODO: CTIME? */
 
        ret   = bch2_inode_write(&trans, iter, &inode_u) ?:
                bch2_trans_commit(&trans, NULL, NULL,
@@ -207,15 +226,6 @@ err:
        }
 }
 
-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)
@@ -242,6 +252,8 @@ static void bcachefs_fuse_mknod(fuse_req_t req, fuse_ino_t dir,
        struct bch_inode_unpacked new_inode;
        int ret;
 
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_mknod(%llu, %s, %x, %x)\n",
+                dir, name, mode, rdev);
        ret = do_create(c, dir, name, mode, rdev, &new_inode);
        if (ret)
                goto err;
@@ -256,6 +268,12 @@ err:
 static void bcachefs_fuse_mkdir(fuse_req_t req, fuse_ino_t dir,
                                const char *name, mode_t mode)
 {
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_mkdir(%llu, %s, %x)\n",
+                dir, name, mode);
+
+       BUG_ON(mode & S_IFMT);
+
+       mode |= S_IFDIR;
        bcachefs_fuse_mknod(req, dir, name, mode, 0);
 }
 
@@ -267,6 +285,8 @@ static void bcachefs_fuse_unlink(fuse_req_t req, fuse_ino_t dir,
        struct qstr qstr = QSTR(name);
        int ret;
 
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_unlink(%llu, %s)\n", dir, name);
+
        dir = map_root_ino(dir);
 
        ret = bch2_trans_do(c, NULL, BTREE_INSERT_ATOMIC|BTREE_INSERT_NOFAIL,
@@ -279,19 +299,13 @@ static void bcachefs_fuse_unlink(fuse_req_t req, fuse_ino_t dir,
 static void bcachefs_fuse_rmdir(fuse_req_t req, fuse_ino_t dir,
                                const char *name)
 {
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_rmdir(%llu, %s)\n", dir, 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,
@@ -304,6 +318,10 @@ static void bcachefs_fuse_rename(fuse_req_t req,
        struct qstr src_name = QSTR(dstname);
        int ret;
 
+       fuse_log(FUSE_LOG_DEBUG,
+                "bcachefs_fuse_rename(%llu, %s, %llu, %s, %x)\n",
+                src_dir, srcname, dst_dir, dstname, flags);
+
        src_dir = map_root_ino(src_dir);
        dst_dir = map_root_ino(dst_dir);
 
@@ -327,6 +345,11 @@ static void bcachefs_fuse_link(fuse_req_t req, fuse_ino_t inum,
        struct qstr qstr = QSTR(newname);
        int ret;
 
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_link(%llu, %llu, %s)\n",
+                inum, newparent, newname);
+
+       newparent = map_root_ino(newparent);
+
        ret = bch2_trans_do(c, NULL, BTREE_INSERT_ATOMIC,
                            bch2_link_trans(&trans, newparent,
                                            inum, &inode_u, &qstr));
@@ -376,53 +399,202 @@ static void bcachefs_fuse_read_endio(struct bio *bio)
        closure_put(bio->bi_private);
 }
 
+struct fuse_align_io {
+       off_t           start;
+       size_t          pad_start;
+       off_t           end;
+       size_t          pad_end;
+       size_t          size;
+};
+
+/* Handle unaligned start and end */
+/* TODO: align to block_bytes, sector size, or page size? */
+static struct fuse_align_io align_io(const struct bch_fs *c, size_t size,
+                                    off_t offset)
+{
+       struct fuse_align_io align;
+
+       BUG_ON(offset < 0);
+
+       align.start = round_down(offset, block_bytes(c));
+       align.pad_start = offset - align.start;
+
+       off_t end = offset + size;
+       align.end = round_up(end, block_bytes(c));
+       align.pad_end = align.end - end;
+
+       align.size = align.end - align.start;
+
+       return align;
+}
+
+/*
+ * Given an aligned number of bytes transferred, figure out how many unaligned
+ * bytes were transferred.
+ */
+static size_t align_fix_up_bytes(const struct fuse_align_io *align,
+                                size_t align_bytes)
+{
+       size_t bytes = 0;
+
+       if (align_bytes > align->pad_start) {
+               bytes = align_bytes - align->pad_start;
+               bytes = bytes > align->pad_end ? bytes - align->pad_end : 0;
+       }
+
+       return bytes;
+}
+
+/*
+ * Read aligned data.
+ */
+static int read_aligned(struct bch_fs *c, fuse_ino_t inum, size_t aligned_size,
+                       off_t aligned_offset, void *buf)
+{
+       BUG_ON(aligned_size & (block_bytes(c) - 1));
+       BUG_ON(aligned_offset & (block_bytes(c) - 1));
+
+       struct bch_io_opts io_opts;
+       if (get_inode_io_opts(c, inum, &io_opts))
+               return -ENOENT;
+
+       struct bch_read_bio rbio;
+       struct bio_vec bv;
+       userbio_init(&rbio.bio, &bv, buf, aligned_size);
+       bio_set_op_attrs(&rbio.bio, REQ_OP_READ, REQ_SYNC);
+       rbio.bio.bi_iter.bi_sector      = aligned_offset >> 9;
+
+       struct closure cl;
+       closure_init_stack(&cl);
+
+       closure_get(&cl);
+       rbio.bio.bi_end_io              = bcachefs_fuse_read_endio;
+       rbio.bio.bi_private             = &cl;
+
+       bch2_read(c, rbio_init(&rbio.bio, io_opts), inum);
+
+       closure_sync(&cl);
+
+       return -blk_status_to_errno(rbio.bio.bi_status);
+}
+
 static void bcachefs_fuse_read(fuse_req_t req, fuse_ino_t inum,
                               size_t size, off_t offset,
                               struct fuse_file_info *fi)
 {
        struct bch_fs *c = fuse_req_userdata(req);
 
-       if ((size|offset) & (block_bytes(c) - 1)) {
-               fuse_log(FUSE_LOG_DEBUG,
-                        "bcachefs_fuse_read: unaligned io not supported.\n");
-               fuse_reply_err(req, EINVAL);
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_read(%llu, %zd, %lld)\n",
+                inum, size, offset);
+
+       /* Check inode size. */
+       struct bch_inode_unpacked bi;
+       int ret = bch2_inode_find_by_inum(c, inum, &bi);
+       if (ret) {
+               fuse_reply_err(req, -ret);
                return;
        }
 
-       struct bch_io_opts io_opts;
-       if (get_inode_io_opts(c, inum, &io_opts)) {
-               fuse_reply_err(req, ENOENT);
+       off_t end = min_t(u64, bi.bi_size, offset + size);
+       if (end <= offset) {
+               fuse_reply_buf(req, NULL, 0);
                return;
        }
+       size = end - offset;
 
-       void *buf = aligned_alloc(max(PAGE_SIZE, size), size);
+       struct fuse_align_io align = align_io(c, size, offset);
+
+       void *buf = aligned_alloc(PAGE_SIZE, align.size);
        if (!buf) {
                fuse_reply_err(req, ENOMEM);
                return;
        }
 
-       struct bch_read_bio     rbio;
+       ret = read_aligned(c, inum, align.size, align.start, buf);
+
+       if (likely(!ret))
+               fuse_reply_buf(req, buf + align.pad_start, size);
+       else
+               fuse_reply_err(req, -ret);
+
+       free(buf);
+}
+
+static int inode_update_times(struct bch_fs *c, fuse_ino_t inum)
+{
+       struct btree_trans trans;
+       struct btree_iter *iter;
+       struct bch_inode_unpacked inode_u;
+       int ret = 0;
+       u64 now;
+
+       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;
+
+       inode_u.bi_mtime = now;
+       inode_u.bi_ctime = now;
+
+       ret = bch2_inode_write(&trans, iter, &inode_u);
+       if (ret)
+               goto err;
+
+       ret = bch2_trans_commit(&trans, NULL, NULL,
+                               BTREE_INSERT_ATOMIC|BTREE_INSERT_NOFAIL);
+
+err:
+       if (ret == -EINTR)
+               goto retry;
+
+       bch2_trans_exit(&trans);
+       return ret;
+}
+
+static int write_aligned(struct bch_fs *c, fuse_ino_t inum,
+                        struct bch_io_opts io_opts, void *buf,
+                        size_t aligned_size, off_t aligned_offset,
+                        off_t new_i_size, size_t *written_out)
+{
+       struct bch_write_op     op = { 0 };
        struct bio_vec          bv;
        struct closure          cl;
 
+       BUG_ON(aligned_size & (block_bytes(c) - 1));
+       BUG_ON(aligned_offset & (block_bytes(c) - 1));
+
+       *written_out = 0;
+
        closure_init_stack(&cl);
-       userbio_init(&rbio.bio, &bv, buf, size);
-       bio_set_op_attrs(&rbio.bio, REQ_OP_READ, REQ_SYNC);
-       rbio.bio.bi_iter.bi_sector      = offset >> 9;
-       rbio.bio.bi_end_io              = bcachefs_fuse_read_endio;
-       rbio.bio.bi_private             = &cl;
 
-       bch2_read(c, rbio_init(&rbio.bio, io_opts), inum);
+       bch2_write_op_init(&op, c, io_opts); /* XXX reads from op?! */
+       op.write_point  = writepoint_hashed(0);
+       op.nr_replicas  = io_opts.data_replicas;
+       op.target       = io_opts.foreground_target;
+       op.pos          = POS(inum, aligned_offset >> 9);
+       op.new_i_size   = new_i_size;
 
-       closure_sync(&cl);
+       userbio_init(&op.wbio.bio, &bv, buf, aligned_size);
+       bio_set_op_attrs(&op.wbio.bio, REQ_OP_WRITE, REQ_SYNC);
 
-       if (likely(!rbio.bio.bi_status)) {
-               fuse_reply_buf(req, buf, size);
-       } else {
-               fuse_reply_err(req, -blk_status_to_errno(rbio.bio.bi_status));
+       if (bch2_disk_reservation_get(c, &op.res, aligned_size >> 9,
+                                     op.nr_replicas, 0)) {
+               /* XXX: use check_range_allocated like dio write path */
+               return -ENOSPC;
        }
 
-       free(buf);
+       closure_call(&op.cl, bch2_write, NULL, &cl);
+       closure_sync(&cl);
+
+       if (!op.error)
+               *written_out = op.written << 9;
+
+       return op.error;
 }
 
 static void bcachefs_fuse_write(fuse_req_t req, fuse_ino_t inum,
@@ -432,52 +604,185 @@ static void bcachefs_fuse_write(fuse_req_t req, fuse_ino_t inum,
 {
        struct bch_fs *c        = fuse_req_userdata(req);
        struct bch_io_opts      io_opts;
-       struct bch_write_op     op;
-       struct bio_vec          bv;
-       struct closure          cl;
+       size_t                  aligned_written;
+       int                     ret = 0;
 
-       if ((size|offset) & (block_bytes(c) - 1)) {
-               fuse_log(FUSE_LOG_DEBUG,
-                        "bcachefs_fuse_write: unaligned io not supported.\n");
-               fuse_reply_err(req, EINVAL);
-               return;
-       }
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_write(%llu, %zd, %lld)\n",
+                inum, size, offset);
 
-       closure_init_stack(&cl);
+       struct fuse_align_io align = align_io(c, size, offset);
+       void *aligned_buf = aligned_alloc(PAGE_SIZE, align.size);
+       BUG_ON(!aligned_buf);
 
        if (get_inode_io_opts(c, inum, &io_opts)) {
-               fuse_reply_err(req, ENOENT);
-               return;
+               ret = -ENOENT;
+               goto err;
        }
 
-       bch2_write_op_init(&op, c, io_opts);
-       op.write_point  = writepoint_hashed(0);
-       op.nr_replicas  = io_opts.data_replicas;
-       op.target       = io_opts.foreground_target;
-       op.pos          = POS(inum, offset >> 9);
+       /* Realign the data and read in start and end, if needed */
 
-       userbio_init(&op.wbio.bio, &bv, (void *) buf, size);
-       bio_set_op_attrs(&op.wbio.bio, REQ_OP_WRITE, REQ_SYNC);
+       /* Read partial start data. */
+       if (align.pad_start) {
+               memset(aligned_buf, 0, block_bytes(c));
 
-       if (bch2_disk_reservation_get(c, &op.res, size >> 9,
-                                     op.nr_replicas, 0)) {
-               /* XXX: use check_range_allocated like dio write path */
-               fuse_reply_err(req, ENOSPC);
-               return;
+               ret = read_aligned(c, inum, block_bytes(c), align.start,
+                                  aligned_buf);
+               if (ret)
+                       goto err;
        }
 
-       closure_call(&op.cl, bch2_write, NULL, &cl);
-       closure_sync(&cl);
+       /*
+        * Read partial end data. If the whole write fits in one block, the
+        * start data and the end data are the same so this isn't needed.
+        */
+       if (align.pad_end &&
+           !(align.pad_start && align.size == block_bytes(c))) {
+               off_t partial_end_start = align.end - block_bytes(c);
+               size_t buf_offset = align.size - block_bytes(c);
 
-       if (op.written) {
-               fuse_reply_write(req, (size_t) op.written << 9);
-       } else {
-               BUG_ON(!op.error);
-               fuse_reply_err(req, -op.error);
+               memset(aligned_buf + buf_offset, 0, block_bytes(c));
+
+               ret = read_aligned(c, inum, block_bytes(c), partial_end_start,
+                                  aligned_buf + buf_offset);
+               if (ret)
+                       goto err;
+       }
+
+       /* Overlay what we want to write. */
+       memcpy(aligned_buf + align.pad_start, buf, size);
+
+       /* Actually write. */
+       ret = write_aligned(c, inum, io_opts, aligned_buf,
+                           align.size, align.start,
+                           offset + size, &aligned_written);
+
+       /* Figure out how many unaligned bytes were written. */
+       size_t written = align_fix_up_bytes(&align, aligned_written);
+       BUG_ON(written > size);
+
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_write: wrote %zd bytes\n",
+                written);
+
+       if (written > 0)
+               ret = 0;
+
+       /*
+        * Update inode times.
+        * TODO: Integrate with bch2_extent_update()
+        */
+       if (!ret)
+               ret = inode_update_times(c, inum);
+
+       if (!ret) {
+               BUG_ON(written == 0);
+               fuse_reply_write(req, written);
+               free(aligned_buf);
+               return;
        }
+
+err:
+       fuse_reply_err(req, -ret);
+       free(aligned_buf);
+}
+
+static void bcachefs_fuse_symlink(fuse_req_t req, const char *link,
+                                 fuse_ino_t dir, const char *name)
+{
+       struct bch_fs *c = fuse_req_userdata(req);
+       struct bch_inode_unpacked new_inode;
+       size_t link_len = strlen(link);
+       int ret;
+
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_symlink(%s, %llu, %s)\n",
+                link, dir, name);
+
+       dir = map_root_ino(dir);
+
+       ret = do_create(c, dir, name, S_IFLNK|S_IRWXUGO, 0, &new_inode);
+       if (ret)
+               goto err;
+
+       struct bch_io_opts io_opts;
+       ret = get_inode_io_opts(c, new_inode.bi_inum, &io_opts);
+       if (ret)
+               goto err;
+
+       struct fuse_align_io align = align_io(c, link_len + 1, 0);
+
+       void *aligned_buf = aligned_alloc(PAGE_SIZE, align.size);
+       BUG_ON(!aligned_buf);
+
+       memset(aligned_buf, 0, align.size);
+       memcpy(aligned_buf, link, link_len); /* already terminated */
+
+       size_t aligned_written;
+       ret = write_aligned(c, new_inode.bi_inum, io_opts, aligned_buf,
+                           align.size, align.start, link_len + 1,
+                           &aligned_written);
+       free(aligned_buf);
+
+       if (ret)
+               goto err;
+
+       size_t written = align_fix_up_bytes(&align, aligned_written);
+       BUG_ON(written != link_len + 1); // TODO: handle short
+
+       ret = inode_update_times(c, new_inode.bi_inum);
+       if (ret)
+               goto err;
+
+       new_inode.bi_size = written;
+
+       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_readlink(fuse_req_t req, fuse_ino_t inum)
+{
+       struct bch_fs *c = fuse_req_userdata(req);
+       char *buf = NULL;
+
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_readlink(%llu)\n", inum);
+
+       struct bch_inode_unpacked bi;
+       int ret = bch2_inode_find_by_inum(c, inum, &bi);
+       if (ret)
+               goto err;
+
+       struct fuse_align_io align = align_io(c, bi.bi_size, 0);
+
+       ret = -ENOMEM;
+       buf = aligned_alloc(PAGE_SIZE, align.size);
+       if (!buf)
+               goto err;
+
+       ret = read_aligned(c, inum, align.size, align.start, buf);
+       if (ret)
+               goto err;
+
+       BUG_ON(buf[align.size - 1] != 0);
+
+       fuse_reply_readlink(req, buf);
+
+err:
+       if (ret)
+               fuse_reply_err(req, -ret);
+
+       free(buf);
 }
 
 #if 0
+/*
+ * FUSE flush is essentially the close() call, however it is not guaranteed
+ * that one flush happens per open/create.
+ *
+ * It doesn't have to do anything, and is mostly relevant for NFS-style
+ * filesystems where close has some relationship to caching.
+ */
 static void bcachefs_fuse_flush(fuse_req_t req, fuse_ino_t inum,
                                struct fuse_file_info *fi)
 {
@@ -503,43 +808,44 @@ static void bcachefs_fuse_opendir(fuse_req_t req, fuse_ino_t inum,
 }
 #endif
 
-struct fuse_dir_entry {
-       u64             ino;
-       unsigned        type;
-       char            name[0];
-};
-
 struct fuse_dir_context {
        struct dir_context      ctx;
        fuse_req_t              req;
        char                    *buf;
        size_t                  bufsize;
-
-       struct fuse_dir_entry   *prev;
 };
 
-static int fuse_send_dir_entry(struct fuse_dir_context *ctx, loff_t pos)
-{
-       struct fuse_dir_entry *de = ctx->prev;
-       ctx->prev = NULL;
-
-       struct stat statbuf = {
-               .st_ino         = unmap_root_ino(de->ino),
-               .st_mode        = de->type << 12,
-       };
+struct fuse_dirent {
+       uint64_t        ino;
+       uint64_t        off;
+       uint32_t        namelen;
+       uint32_t        type;
+       char name[];
+};
 
-       size_t len = fuse_add_direntry(ctx->req, ctx->buf, ctx->bufsize,
-                                      de->name, &statbuf, pos);
+#define FUSE_NAME_OFFSET offsetof(struct fuse_dirent, name)
+#define FUSE_DIRENT_ALIGN(x) \
+       (((x) + sizeof(uint64_t) - 1) & ~(sizeof(uint64_t) - 1))
 
-       free(de);
+static size_t fuse_add_direntry2(char *buf, size_t bufsize,
+                                const char *name, int namelen,
+                                const struct stat *stbuf, off_t off)
+{
+       size_t entlen           = FUSE_NAME_OFFSET + namelen;
+       size_t entlen_padded    = FUSE_DIRENT_ALIGN(entlen);
+       struct fuse_dirent *dirent = (struct fuse_dirent *) buf;
 
-       if (len > ctx->bufsize)
-               return -EINVAL;
+       if ((buf == NULL) || (entlen_padded > bufsize))
+               return entlen_padded;
 
-       ctx->buf        += len;
-       ctx->bufsize    -= len;
+       dirent->ino = stbuf->st_ino;
+       dirent->off = off;
+       dirent->namelen = namelen;
+       dirent->type = (stbuf->st_mode & S_IFMT) >> 12;
+       memcpy(dirent->name, name, namelen);
+       memset(dirent->name + namelen, 0, entlen_padded - entlen);
 
-       return 0;
+       return entlen_padded;
 }
 
 static int fuse_filldir(struct dir_context *_ctx,
@@ -549,47 +855,42 @@ static int fuse_filldir(struct dir_context *_ctx,
        struct fuse_dir_context *ctx =
                container_of(_ctx, struct fuse_dir_context, ctx);
 
-       fuse_log(FUSE_LOG_DEBUG, "fuse_filldir(ctx={.ctx={.pos=%llu}}, "
-                "name=%s, namelen=%d, pos=%lld, dir=%llu, type=%u)\n",
-                ctx->ctx.pos, name, namelen, pos, ino, type);
+       struct stat statbuf = {
+               .st_ino         = unmap_root_ino(ino),
+               .st_mode        = type << 12,
+       };
 
-       /*
-        * We have to emit directory entries after reading the next entry,
-        * because the previous entry contains a pointer to next.
-        */
-       if (ctx->prev) {
-               int ret = fuse_send_dir_entry(ctx, pos);
-               if (ret)
-                       return ret;
-       }
+       fuse_log(FUSE_LOG_DEBUG, "fuse_filldir(name=%s inum=%llu pos=%llu)\n",
+                name, statbuf.st_ino, pos);
 
-       struct fuse_dir_entry *cur = malloc(sizeof *cur + namelen + 1);
-       cur->ino = ino;
-       cur->type = type;
-       memcpy(cur->name, name, namelen);
-       cur->name[namelen] = 0;
+       size_t len = fuse_add_direntry2(ctx->buf,
+                                       ctx->bufsize,
+                                       name,
+                                       namelen,
+                                       &statbuf,
+                                       pos + 1);
+
+       if (len > ctx->bufsize)
+               return -1;
 
-       ctx->prev = cur;
+       ctx->buf        += len;
+       ctx->bufsize    -= len;
 
        return 0;
 }
 
 static bool handle_dots(struct fuse_dir_context *ctx, fuse_ino_t dir)
 {
-       int ret = 0;
-
        if (ctx->ctx.pos == 0) {
-               ret = fuse_filldir(&ctx->ctx, ".", 1, ctx->ctx.pos,
-                                  unmap_root_ino(dir), DT_DIR);
-               if (ret < 0)
+               if (fuse_filldir(&ctx->ctx, ".", 1, ctx->ctx.pos,
+                                dir, DT_DIR) < 0)
                        return false;
                ctx->ctx.pos = 1;
        }
 
        if (ctx->ctx.pos == 1) {
-               ret = fuse_filldir(&ctx->ctx, "..", 2, ctx->ctx.pos,
-                                  /*TODO: parent*/ 1, DT_DIR);
-               if (ret < 0)
+               if (fuse_filldir(&ctx->ctx, "..", 2, ctx->ctx.pos,
+                                /*TODO: parent*/ 1, DT_DIR) < 0)
                        return false;
                ctx->ctx.pos = 2;
        }
@@ -631,20 +932,7 @@ static void bcachefs_fuse_readdir(fuse_req_t req, fuse_ino_t dir,
                goto reply;
 
        ret = bch2_readdir(c, dir, &ctx.ctx);
-
 reply:
-       /*
-        * If we have something to send, the error above doesn't matter.
-        *
-        * Alternatively, if this send fails, but we previously sent something,
-        * then this is a success.
-        */
-       if (ctx.prev) {
-               ret = fuse_send_dir_entry(&ctx, ctx.ctx.pos);
-               if (ret && ctx.buf != buf)
-                       ret = 0;
-       }
-
        if (!ret) {
                fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_readdir reply %zd\n",
                                        ctx.buf - buf);
@@ -732,6 +1020,9 @@ static void bcachefs_fuse_create(fuse_req_t req, fuse_ino_t dir,
        struct bch_inode_unpacked new_inode;
        int ret;
 
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_create(%llu, %s, %x)\n",
+                dir, name, mode);
+
        ret = do_create(c, dir, name, mode, 0, &new_inode);
        if (ret)
                goto err;
@@ -771,7 +1062,7 @@ static const struct fuse_lowlevel_ops bcachefs_fuse_ops = {
        .mkdir          = bcachefs_fuse_mkdir,
        .unlink         = bcachefs_fuse_unlink,
        .rmdir          = bcachefs_fuse_rmdir,
-       //.symlink      = bcachefs_fuse_symlink,
+       .symlink        = bcachefs_fuse_symlink,
        .rename         = bcachefs_fuse_rename,
        .link           = bcachefs_fuse_link,
        .open           = bcachefs_fuse_open,
@@ -954,6 +1245,9 @@ int cmd_fusemount(int argc, char *argv[])
        if (fuse_session_mount(se, fuse_opts.mountpoint))
                die("fuse_mount err: %m");
 
+       /* This print statement is a trigger for tests. */
+       printf("Fuse mount initialized.\n");
+
        fuse_daemonize(fuse_opts.foreground);
 
        ret = fuse_session_loop(se);
@@ -970,3 +1264,5 @@ out:
 
        return ret ? 1 : 0;
 }
+
+#endif /* BCACHEFS_FUSE */