]> git.sesse.net Git - bcachefs-tools-debian/blobdiff - cmd_fusemount.c
convert main() from C to Rust
[bcachefs-tools-debian] / cmd_fusemount.c
index a9d6305bf6a44733cfeda7c16c0001fe5829d500..d81f31884cb27a2704cd898ff688fd51f5f139c5 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_read.h"
+#include "libbcachefs/io_write.h"
 #include "libbcachefs/opts.h"
 #include "libbcachefs/super.h"
 
 /* XXX cut and pasted from fsck.c */
 #define QSTR(n) { { { .len = strlen(n) } }, .name = n }
 
-static inline u64 map_root_ino(u64 ino)
+/* used by write_aligned function for waiting on bch2_write closure */
+struct write_aligned_op_t {
+        struct closure cl;
+
+        /* must be last: */
+        struct bch_write_op             op;
+};
+
+
+static inline subvol_inum map_root_ino(u64 ino)
 {
-       return ino == 1 ? 4096 : ino;
+       return (subvol_inum) { 1, ino == 1 ? 4096 : ino };
 }
 
 static inline u64 unmap_root_ino(u64 ino)
@@ -42,6 +57,7 @@ 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 +76,7 @@ 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 +84,17 @@ 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;
@@ -75,82 +102,96 @@ static void bcachefs_fuse_destroy(void *arg)
        bch2_fs_stop(c);
 }
 
-static void bcachefs_fuse_lookup(fuse_req_t req, fuse_ino_t dir,
+static void bcachefs_fuse_lookup(fuse_req_t req, fuse_ino_t dir_ino,
                                 const char *name)
 {
+       subvol_inum dir = map_root_ino(dir_ino);
        struct bch_fs *c = fuse_req_userdata(req);
        struct bch_inode_unpacked bi;
        struct qstr qstr = QSTR(name);
-       u64 inum;
+       subvol_inum inum;
        int ret;
 
-       dir = map_root_ino(dir);
+       fuse_log(FUSE_LOG_DEBUG, "fuse_lookup(dir=%llu name=%s)\n",
+                dir.inum, name);
 
-       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;
+       }
 
-       inum = bch2_dirent_lookup(c, dir, &qstr);
-       if (!inum) {
-               ret = -ENOENT;
-               goto err;
+       struct bch_hash_info hash_info = bch2_hash_info_init(c, &bi);
+
+       ret = bch2_dirent_lookup(c, dir, &hash_info, &qstr, &inum);
+       if (ret) {
+               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);
 }
 
-static void bcachefs_fuse_getattr(fuse_req_t req, fuse_ino_t inum,
+static void bcachefs_fuse_getattr(fuse_req_t req, fuse_ino_t ino,
                                  struct fuse_file_info *fi)
 {
+       subvol_inum inum = map_root_ino(ino);
        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);
+       fuse_log(FUSE_LOG_DEBUG, "fuse_getattr(inum=%llu)\n", inum.inum);
 
-       ret = bch2_inode_find_by_inum(c, inum, &bi);
+       int 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);
 }
 
-static void bcachefs_fuse_setattr(fuse_req_t req, fuse_ino_t inum,
+static void bcachefs_fuse_setattr(fuse_req_t req, fuse_ino_t ino,
                                  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;
+       struct btree_trans *trans;
+       struct btree_iter iter;
        u64 now;
        int ret;
 
-       inum = map_root_ino(inum);
+       subvol_inum inum = map_root_ino(ino);
+
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_setattr(%llu, %x)\n", inum.inum, to_set);
 
-       bch2_trans_init(&trans, c, 0, 0);
+       trans = bch2_trans_get(c);
 retry:
-       bch2_trans_begin(&trans);
+       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;
 
@@ -170,16 +211,17 @@ 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,
-                                 BTREE_INSERT_ATOMIC|
-                                 BTREE_INSERT_NOFAIL);
+       ret   = bch2_inode_write(trans, &iter, &inode_u) ?:
+               bch2_trans_commit(trans, NULL, NULL,
+                                 BCH_TRANS_COMMIT_no_enospc);
 err:
+        bch2_trans_iter_exit(trans, &iter);
        if (ret == -EINTR)
                goto retry;
 
-       bch2_trans_exit(&trans);
+       bch2_trans_put(trans);
 
        if (!ret) {
                *attr = inode_to_stat(c, &inode_u);
@@ -189,41 +231,37 @@ 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,
+static int do_create(struct bch_fs *c, subvol_inum 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);
+       uid_t uid = 0;
+       gid_t gid = 0;
 
        bch2_inode_init_early(c, new_inode);
 
-       return bch2_trans_do(c, NULL, 0,
-                       bch2_create_trans(&trans,
+       return bch2_trans_do(c, NULL, NULL, 0,
+                       bch2_create_trans(trans,
                                dir, &dir_u,
                                new_inode, &qstr,
-                               0, 0, mode, rdev, NULL, NULL));
+                               uid, gid, mode, rdev, NULL, NULL,
+                               (subvol_inum) { 0 }, 0));
 }
 
-static void bcachefs_fuse_mknod(fuse_req_t req, fuse_ino_t dir,
+static void bcachefs_fuse_mknod(fuse_req_t req, fuse_ino_t dir_ino,
                                const char *name, mode_t mode,
                                dev_t rdev)
 {
+       subvol_inum dir = map_root_ino(dir_ino);
        struct bch_fs *c = fuse_req_userdata(req);
        struct bch_inode_unpacked new_inode;
        int ret;
 
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_mknod(%llu, %s, %x, %x)\n",
+                dir.inum, name, mode, rdev);
+
        ret = do_create(c, dir, name, mode, rdev, &new_inode);
        if (ret)
                goto err;
@@ -238,22 +276,29 @@ 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);
 }
 
-static void bcachefs_fuse_unlink(fuse_req_t req, fuse_ino_t dir,
+static void bcachefs_fuse_unlink(fuse_req_t req, fuse_ino_t dir_ino,
                                 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;
+       subvol_inum dir = map_root_ino(dir_ino);
 
-       dir = map_root_ino(dir);
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_unlink(%llu, %s)\n", dir.inum, name);
 
-       ret = bch2_trans_do(c, NULL, BTREE_INSERT_ATOMIC|BTREE_INSERT_NOFAIL,
-                           bch2_unlink_trans(&trans, dir, &dir_u,
-                                             &inode_u, &qstr));
+       int ret = bch2_trans_do(c, NULL, NULL,
+                               BCH_TRANS_COMMIT_no_enospc,
+                           bch2_unlink_trans(trans, dir, &dir_u,
+                                             &inode_u, &qstr, false));
 
        fuse_reply_err(req, -ret);
 }
@@ -261,22 +306,14 @@ 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)
 {
-       dir = map_root_ino(dir);
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_rmdir(%llu, %s)\n", dir, name);
 
        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,
+                                fuse_ino_t src_dir_ino, const char *srcname,
+                                fuse_ino_t dst_dir_ino, const char *dstname,
                                 unsigned flags)
 {
        struct bch_fs *c = fuse_req_userdata(req);
@@ -284,14 +321,17 @@ static void bcachefs_fuse_rename(fuse_req_t req,
        struct bch_inode_unpacked src_inode_u, dst_inode_u;
        struct qstr dst_name = QSTR(srcname);
        struct qstr src_name = QSTR(dstname);
+       subvol_inum src_dir = map_root_ino(src_dir_ino);
+       subvol_inum dst_dir = map_root_ino(dst_dir_ino);
        int ret;
 
-       src_dir = map_root_ino(src_dir);
-       dst_dir = map_root_ino(dst_dir);
+       fuse_log(FUSE_LOG_DEBUG,
+                "bcachefs_fuse_rename(%llu, %s, %llu, %s, %x)\n",
+                src_dir.inum, srcname, dst_dir.inum, dstname, flags);
 
        /* XXX handle overwrites */
-       ret = bch2_trans_do(c, NULL, BTREE_INSERT_ATOMIC,
-               bch2_rename_trans(&trans,
+       ret = bch2_trans_do(c, NULL, NULL, 0,
+               bch2_rename_trans(trans,
                                  src_dir, &src_dir_u,
                                  dst_dir, &dst_dir_u,
                                  &src_inode_u, &dst_inode_u,
@@ -301,16 +341,21 @@ static void bcachefs_fuse_rename(fuse_req_t req,
        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)
+static void bcachefs_fuse_link(fuse_req_t req, fuse_ino_t ino,
+                              fuse_ino_t newparent_ino, 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);
+       subvol_inum newparent   = map_root_ino(newparent_ino);
+       subvol_inum inum        = map_root_ino(ino);
        int ret;
 
-       ret = bch2_trans_do(c, NULL, BTREE_INSERT_ATOMIC,
-                           bch2_link_trans(&trans, newparent,
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_link(%llu, %llu, %s)\n",
+                inum.inum, newparent.inum, newname);
+
+       ret = bch2_trans_do(c, NULL, NULL, 0,
+                           bch2_link_trans(trans, newparent, &dir_u,
                                            inum, &inode_u, &qstr));
 
        if (!ret) {
@@ -321,20 +366,443 @@ 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, NULL, bv, 1, 0);
+       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, subvol_inum inum, struct bch_io_opts *opts)
+{
+       struct bch_inode_unpacked inode;
+       if (bch2_inode_find_by_inum(c, inum, &inode))
+               return -EINVAL;
+
+       bch2_inode_opts_get(opts, c, &inode);
+       return 0;
 }
 
-static void bcachefs_fuse_read(fuse_req_t req, fuse_ino_t inum,
-                              size_t size, off_t off,
+static void bcachefs_fuse_read_endio(struct bio *bio)
+{
+       closure_put(bio->bi_private);
+}
+
+
+static void bcachefs_fuse_write_endio(struct bch_write_op *op)
+{
+       struct write_aligned_op_t *w = container_of(op,struct write_aligned_op_t,op);
+       closure_put(&w->cl);
+}
+
+
+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, subvol_inum 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 ino,
+                              size_t size, off_t offset,
                               struct fuse_file_info *fi)
 {
+       subvol_inum inum = map_root_ino(ino);
+       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, subvol_inum inum)
+{
+       struct btree_trans *trans;
+       struct btree_iter iter;
+       struct bch_inode_unpacked inode_u;
+       int ret = 0;
+       u64 now;
+
+       trans = bch2_trans_get(c);
+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,
+                               BCH_TRANS_COMMIT_no_enospc);
+err:
+        bch2_trans_iter_exit(trans, &iter);
+       if (ret == -EINTR)
+               goto retry;
+
+       bch2_trans_put(trans);
+       return ret;
+}
+
+static int write_aligned(struct bch_fs *c, subvol_inum 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 write_aligned_op_t w = { 0 }
+;
+       struct bch_write_op     *op = &w.op;
+       struct bio_vec          bv;
+
+       BUG_ON(aligned_size & (block_bytes(c) - 1));
+       BUG_ON(aligned_offset & (block_bytes(c) - 1));
+
+       *written_out = 0;
+
+       closure_init_stack(&w.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->subvol      = inum.subvol;
+       op->pos         = POS(inum.inum, aligned_offset >> 9);
+       op->new_i_size  = new_i_size;
+       op->end_io = bcachefs_fuse_write_endio;
+
+       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_get(&w.cl);
+
+       closure_call(&op->cl, bch2_write, NULL, NULL);
+
+       closure_sync(&w.cl);
+
+       if (!op->error)
+               *written_out = op->written << 9;
+
+       return op->error;
+}
+
+static void bcachefs_fuse_write(fuse_req_t req, fuse_ino_t ino,
+                               const char *buf, size_t size,
+                               off_t offset,
+                               struct fuse_file_info *fi)
+{
+       subvol_inum inum = map_root_ino(ino);
+       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_ino, const char *name)
+{
+       subvol_inum dir = map_root_ino(dir_ino);
        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.inum, name);
+
+       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, dir, &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 */
+
+       subvol_inum inum = (subvol_inum) { dir.subvol, new_inode.bi_inum };
+
+       size_t aligned_written;
+       ret = write_aligned(c, 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, 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 ino)
+{
+       subvol_inum inum = map_root_ino(ino);
+       struct bch_fs *c = fuse_req_userdata(req);
+       char *buf = NULL;
+
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_readlink(%llu)\n", inum.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)
 {
@@ -367,59 +835,142 @@ 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 void bcachefs_fuse_readdir(fuse_req_t req, fuse_ino_t dir,
+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_ino,
                                  size_t size, off_t off,
                                  struct fuse_file_info *fi)
 {
+       subvol_inum dir = map_root_ino(dir_ino);
        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.inum, size, off);
+
+       ret = bch2_inode_find_by_inum(c, dir, &bi);
+       if (ret)
+               goto reply;
+
+       if (!S_ISDIR(bi.bi_mode)) {
+               ret = -ENOTDIR;
+               goto reply;
+       }
 
-       dir = map_root_ino(dir);
+       if (!handle_dots(&ctx, dir.inum))
+               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)
 {
@@ -480,14 +1031,18 @@ static void bcachefs_fuse_removexattr(fuse_req_t req, fuse_ino_t inum,
 }
 #endif
 
-static void bcachefs_fuse_create(fuse_req_t req, fuse_ino_t dir,
+static void bcachefs_fuse_create(fuse_req_t req, fuse_ino_t dir_ino,
                                 const char *name, mode_t mode,
                                 struct fuse_file_info *fi)
 {
+       subvol_inum dir = map_root_ino(dir_ino);
        struct bch_fs *c = fuse_req_userdata(req);
        struct bch_inode_unpacked new_inode;
        int ret;
 
+       fuse_log(FUSE_LOG_DEBUG, "bcachefs_fuse_create(%llu, %s, %x)\n",
+                dir.inum, name, mode);
+
        ret = do_create(c, dir, name, mode, 0, &new_inode);
        if (ret)
                goto err;
@@ -497,7 +1052,6 @@ static void bcachefs_fuse_create(fuse_req_t req, fuse_ino_t dir,
        return;
 err:
        fuse_reply_err(req, -ret);
-
 }
 
 #if 0
@@ -517,6 +1071,7 @@ 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 +1081,18 @@ 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,
@@ -685,6 +1241,17 @@ int cmd_fusemount(int argc, char *argv[])
        }
        tokenize_devices(&ctx);
 
+       struct printbuf fsname = PRINTBUF;
+       prt_printf(&fsname, "fsname=");
+       for (i = 0; i < ctx.nr_devices; ++i) {
+               if (i)
+                       prt_str(&fsname, ":");
+               prt_str(&fsname, ctx.devices[i]);
+       }
+
+       fuse_opt_add_arg(&args, "-o");
+       fuse_opt_add_arg(&args, fsname.buf);
+
        /* Open bch */
        printf("Opening bcachefs filesystem on:\n");
        for (i = 0; i < ctx.nr_devices; ++i)
@@ -693,7 +1260,7 @@ 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 +1275,14 @@ 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");
+
+       if (fuse_opts.foreground == 0){
+               printf("Fuse forcing to foreground mode, due gcc constructors usage.\n");
+               fuse_opts.foreground = 1;
+       }
+
        fuse_daemonize(fuse_opts.foreground);
 
        ret = fuse_session_loop(se);
@@ -724,3 +1299,5 @@ out:
 
        return ret ? 1 : 0;
 }
+
+#endif /* BCACHEFS_FUSE */