]> git.sesse.net Git - bcachefs-tools-debian/blobdiff - cmd_fusemount.c
Update bcachefs sources to ee560a3929 bcachefs: Print version, options earlier in...
[bcachefs-tools-debian] / cmd_fusemount.c
index a9d6305bf6a44733cfeda7c16c0001fe5829d500..4470f83844a128b9f83f79d091c788b0d976c43c 100644 (file)
@@ -1,3 +1,5 @@
+#ifdef BCACHEFS_FUSE
+
 #include <errno.h>
 #include <float.h>
 #include <getopt.h>
 #include "tools-util.h"
 
 #include "libbcachefs/bcachefs.h"
+#include "libbcachefs/alloc_foreground.h"
 #include "libbcachefs/btree_iter.h"
 #include "libbcachefs/buckets.h"
 #include "libbcachefs/dirent.h"
+#include "libbcachefs/errcode.h"
 #include "libbcachefs/error.h"
 #include "libbcachefs/fs-common.h"
 #include "libbcachefs/inode.h"
+#include "libbcachefs/io.h"
 #include "libbcachefs/opts.h"
 #include "libbcachefs/super.h"
 
@@ -42,6 +47,7 @@ static struct stat inode_to_stat(struct bch_fs *c,
                                 struct bch_inode_unpacked *bi)
 {
        return (struct stat) {
+               .st_ino         = unmap_root_ino(bi->bi_inum),
                .st_size        = bi->bi_size,
                .st_mode        = bi->bi_mode,
                .st_uid         = bi->bi_uid,
@@ -60,7 +66,7 @@ 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,
@@ -68,6 +74,17 @@ static struct fuse_entry_param inode_to_entry(struct bch_fs *c,
        };
 }
 
+static void bcachefs_fuse_init(void *arg, struct fuse_conn_info *conn)
+{
+       if (conn->capable & FUSE_CAP_WRITEBACK_CACHE) {
+               fuse_log(FUSE_LOG_DEBUG, "fuse_init: activating writeback\n");
+               conn->want |= FUSE_CAP_WRITEBACK_CACHE;
+       } else
+               fuse_log(FUSE_LOG_DEBUG, "fuse_init: writeback not capable\n");
+
+       //conn->want |= FUSE_CAP_POSIX_ACL;
+}
+
 static void bcachefs_fuse_destroy(void *arg)
 {
        struct bch_fs *c = arg;
@@ -84,26 +101,41 @@ 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);
 
-       pr_info("dir %llu name %s", (u64) dir, name);
+       ret = bch2_inode_find_by_inum(c, dir, &bi);
+       if (ret) {
+               fuse_reply_err(req, -ret);
+               return;
+       }
+
+       struct bch_hash_info hash_info = bch2_hash_info_init(c, &bi);
 
-       inum = bch2_dirent_lookup(c, dir, &qstr);
+       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);
 }
 
@@ -115,17 +147,19 @@ static void bcachefs_fuse_getattr(fuse_req_t req, fuse_ino_t inum,
        struct stat attr;
        int ret;
 
-       inum = map_root_ino(inum);
+       fuse_log(FUSE_LOG_DEBUG, "fuse_getattr(inum=%llu)\n",
+                inum);
 
-       pr_info("inum %llu", (u64) 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);
@@ -138,10 +172,13 @@ static void bcachefs_fuse_setattr(fuse_req_t req, fuse_ino_t inum,
        struct bch_fs *c = fuse_req_userdata(req);
        struct bch_inode_unpacked inode_u;
        struct btree_trans trans;
-       struct btree_iter *iter;
+       struct btree_iter iter;
        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);
@@ -149,8 +186,7 @@ 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);
+       ret = bch2_inode_peek(&trans, &iter, &inode_u, inum, BTREE_ITER_INTENT);
        if (ret)
                goto err;
 
@@ -170,12 +206,13 @@ 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) ?:
+       ret   = bch2_inode_write(&trans, &iter, &inode_u) ?:
                bch2_trans_commit(&trans, NULL, NULL,
-                                 BTREE_INSERT_ATOMIC|
                                  BTREE_INSERT_NOFAIL);
 err:
+        bch2_trans_iter_exit(&trans, &iter);
        if (ret == -EINTR)
                goto retry;
 
@@ -189,15 +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)
@@ -209,7 +237,7 @@ static int do_create(struct bch_fs *c, u64 dir,
 
        bch2_inode_init_early(c, new_inode);
 
-       return bch2_trans_do(c, NULL, 0,
+       return bch2_trans_do(c, NULL, NULL, 0,
                        bch2_create_trans(&trans,
                                dir, &dir_u,
                                new_inode, &qstr,
@@ -224,6 +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;
@@ -238,6 +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);
 }
 
@@ -249,9 +285,11 @@ 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,
+       ret = bch2_trans_do(c, NULL, NULL, BTREE_INSERT_NOFAIL,
                            bch2_unlink_trans(&trans, dir, &dir_u,
                                              &inode_u, &qstr));
 
@@ -261,19 +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,
@@ -286,11 +318,15 @@ 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);
 
        /* XXX handle overwrites */
-       ret = bch2_trans_do(c, NULL, BTREE_INSERT_ATOMIC,
+       ret = bch2_trans_do(c, NULL, NULL, 0,
                bch2_rename_trans(&trans,
                                  src_dir, &src_dir_u,
                                  dst_dir, &dst_dir_u,
@@ -305,13 +341,18 @@ 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 bch_inode_unpacked dir_u, inode_u;
        struct qstr qstr = QSTR(newname);
        int ret;
 
-       ret = bch2_trans_do(c, NULL, BTREE_INSERT_ATOMIC,
+       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, NULL, 0,
                            bch2_link_trans(&trans, newparent,
-                                           inum, &inode_u, &qstr));
+                                           inum, &dir_u, &inode_u, &qstr));
 
        if (!ret) {
                struct fuse_entry_param e = inode_to_entry(c, &inode_u);
@@ -321,20 +362,427 @@ static void bcachefs_fuse_link(fuse_req_t req, fuse_ino_t inum,
        }
 }
 
-#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);
+       fi->direct_io           = false;
+       fi->keep_cache          = true;
+       fi->cache_readdir       = true;
+
+       fuse_reply_open(req, fi);
+}
+
+static void userbio_init(struct bio *bio, struct bio_vec *bv,
+                        void *buf, size_t size)
+{
+       bio_init(bio, bv, 1);
+       bio->bi_iter.bi_size    = size;
+       bv->bv_page             = buf;
+       bv->bv_len              = size;
+       bv->bv_offset           = 0;
+}
+
+static int get_inode_io_opts(struct bch_fs *c, u64 inum,
+                            struct bch_io_opts *opts)
+{
+       struct bch_inode_unpacked inode;
+       if (bch2_inode_find_by_inum(c, inum, &inode))
+               return -EINVAL;
+
+       *opts = bch2_opts_to_inode_opts(c->opts);
+       bch2_io_opts_apply(opts, bch2_inode_opts_get(&inode));
+       return 0;
+}
+
+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 off,
+                              size_t size, off_t offset,
                               struct fuse_file_info *fi)
 {
        struct bch_fs *c = fuse_req_userdata(req);
+
+       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;
+       }
+
+       off_t end = min_t(u64, bi.bi_size, offset + size);
+       if (end <= offset) {
+               fuse_reply_buf(req, NULL, 0);
+               return;
+       }
+       size = end - offset;
+
+       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;
+       }
+
+       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);
+
+       ret = bch2_inode_peek(&trans, &iter, &inode_u, inum, BTREE_ITER_INTENT);
+       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_NOFAIL);
+
+err:
+        bch2_trans_iter_exit(&trans, &iter);
+       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);
+
+       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;
+
+       userbio_init(&op.wbio.bio, &bv, buf, aligned_size);
+       bio_set_op_attrs(&op.wbio.bio, REQ_OP_WRITE, REQ_SYNC);
+
+       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;
+       }
+
+       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,
+                               const char *buf, size_t size,
+                               off_t offset,
+                               struct fuse_file_info *fi)
+{
+       struct bch_fs *c        = fuse_req_userdata(req);
+       struct bch_io_opts      io_opts;
+       size_t                  aligned_written;
+       int                     ret = 0;
+
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_write(%llu, %zd, %lld)\n",
+                inum, size, offset);
+
+       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)) {
+               ret = -ENOENT;
+               goto err;
+       }
+
+       /* Realign the data and read in start and end, if needed */
+
+       /* Read partial start data. */
+       if (align.pad_start) {
+               memset(aligned_buf, 0, block_bytes(c));
+
+               ret = read_aligned(c, inum, block_bytes(c), align.start,
+                                  aligned_buf);
+               if (ret)
+                       goto err;
+       }
+
+       /*
+        * 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);
+
+               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)
 {
@@ -367,31 +815,87 @@ struct fuse_dir_context {
        size_t                  bufsize;
 };
 
+struct fuse_dirent {
+       uint64_t        ino;
+       uint64_t        off;
+       uint32_t        namelen;
+       uint32_t        type;
+       char name[];
+};
+
+#define FUSE_NAME_OFFSET offsetof(struct fuse_dirent, name)
+#define FUSE_DIRENT_ALIGN(x) \
+       (((x) + sizeof(uint64_t) - 1) & ~(sizeof(uint64_t) - 1))
+
+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 ((buf == NULL) || (entlen_padded > bufsize))
+               return entlen_padded;
+
+       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 entlen_padded;
+}
+
 static int fuse_filldir(struct dir_context *_ctx,
                        const char *name, int namelen,
-                       loff_t pos, u64 dir, unsigned type)
+                       loff_t pos, u64 ino, 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_ino         = unmap_root_ino(ino),
                .st_mode        = type << 12,
        };
 
-       size_t len = fuse_add_direntry(ctx->req,
-                                      ctx->buf,
-                                      ctx->bufsize,
-                                      name,
-                                      &statbuf,
-                                      pos + 1);
+       fuse_log(FUSE_LOG_DEBUG, "fuse_filldir(name=%s inum=%llu pos=%llu)\n",
+                name, statbuf.st_ino, pos);
+
+       size_t len = fuse_add_direntry2(ctx->buf,
+                                       ctx->bufsize,
+                                       name,
+                                       namelen,
+                                       &statbuf,
+                                       pos + 1);
 
        if (len > ctx->bufsize)
-               return 0;
+               return -1;
 
        ctx->buf        += len;
        ctx->bufsize    -= len;
-       return 1;
+
+       return 0;
+}
+
+static bool handle_dots(struct fuse_dir_context *ctx, fuse_ino_t dir)
+{
+       if (ctx->ctx.pos == 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) {
+               if (fuse_filldir(&ctx->ctx, "..", 2, ctx->ctx.pos,
+                                /*TODO: parent*/ 1, DT_DIR) < 0)
+                       return false;
+               ctx->ctx.pos = 2;
+       }
+
+       return true;
 }
 
 static void bcachefs_fuse_readdir(fuse_req_t req, fuse_ino_t dir,
@@ -399,27 +903,55 @@ static void bcachefs_fuse_readdir(fuse_req_t req, fuse_ino_t dir,
                                  struct fuse_file_info *fi)
 {
        struct bch_fs *c = fuse_req_userdata(req);
-       char buf[4096];
+       struct bch_inode_unpacked bi;
+       char *buf = calloc(size, 1);
        struct fuse_dir_context ctx = {
                .ctx.actor      = fuse_filldir,
                .ctx.pos        = off,
                .req            = req,
                .buf            = buf,
-               .bufsize        = sizeof(buf),
+               .bufsize        = size,
        };
-       int ret;
+       int ret = 0;
+
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_readdir(dir=%llu, size=%zu, "
+                "off=%lld)\n", dir, size, off);
 
        dir = map_root_ino(dir);
 
+       ret = bch2_inode_find_by_inum(c, dir, &bi);
+       if (ret)
+               goto reply;
+
+       if (!S_ISDIR(bi.bi_mode)) {
+               ret = -ENOTDIR;
+               goto reply;
+       }
+
+       if (!handle_dots(&ctx, dir))
+               goto reply;
+
        ret = bch2_readdir(c, dir, &ctx.ctx);
+reply:
        if (!ret) {
+               fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_readdir reply %zd\n",
+                                       ctx.buf - buf);
                fuse_reply_buf(req, buf, ctx.buf - buf);
        } else {
                fuse_reply_err(req, -ret);
        }
+
+       free(buf);
 }
 
 #if 0
+static void bcachefs_fuse_readdirplus(fuse_req_t req, fuse_ino_t dir,
+                                     size_t size, off_t off,
+                                     struct fuse_file_info *fi)
+{
+
+}
+
 static void bcachefs_fuse_releasedir(fuse_req_t req, fuse_ino_t inum,
                                     struct fuse_file_info *fi)
 {
@@ -488,6 +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;
@@ -517,6 +1052,7 @@ static void bcachefs_fuse_fallocate(fuse_req_t req, fuse_ino_t inum, int mode,
 #endif
 
 static const struct fuse_lowlevel_ops bcachefs_fuse_ops = {
+       .init           = bcachefs_fuse_init,
        .destroy        = bcachefs_fuse_destroy,
        .lookup         = bcachefs_fuse_lookup,
        .getattr        = bcachefs_fuse_getattr,
@@ -526,17 +1062,18 @@ 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,
-       //.read         = bcachefs_fuse_read,
-       //.write        = bcachefs_fuse_write,
+       .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,
+       //.readdirplus  = bcachefs_fuse_readdirplus,
        //.releasedir   = bcachefs_fuse_releasedir,
        //.fsyncdir     = bcachefs_fuse_fsyncdir,
        .statfs         = bcachefs_fuse_statfs,
@@ -693,7 +1230,7 @@ int cmd_fusemount(int argc, char *argv[])
        c = bch2_fs_open(ctx.devices, ctx.nr_devices, bch_opts);
        if (IS_ERR(c))
                die("error opening %s: %s", ctx.devices_str,
-                   strerror(-PTR_ERR(c)));
+                   bch2_err_str(PTR_ERR(c)));
 
        /* Fuse */
        struct fuse_session *se =
@@ -708,6 +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);
@@ -724,3 +1264,5 @@ out:
 
        return ret ? 1 : 0;
 }
+
+#endif /* BCACHEFS_FUSE */