initial code repo
[stor4nfv.git] / src / ceph / src / rbd_fuse / rbd-fuse.cc
diff --git a/src/ceph/src/rbd_fuse/rbd-fuse.cc b/src/ceph/src/rbd_fuse/rbd-fuse.cc
new file mode 100644 (file)
index 0000000..6295097
--- /dev/null
@@ -0,0 +1,888 @@
+/*
+ * rbd-fuse
+ */
+#define FUSE_USE_VERSION 30
+
+#include "include/int_types.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <fuse.h>
+#include <pthread.h>
+#include <string.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <assert.h>
+#include <string>
+#include <mutex>
+
+#if defined(__FreeBSD__)
+#include <sys/param.h>
+#endif
+
+#include "include/compat.h"
+#include "include/rbd/librbd.h"
+
+static int gotrados = 0;
+char *pool_name;
+char *mount_image_name;
+rados_t cluster;
+rados_ioctx_t ioctx;
+
+std::mutex readdir_lock;
+
+struct rbd_stat {
+       u_char valid;
+       rbd_image_info_t rbd_info;
+};
+
+struct rbd_options {
+       char *ceph_config;
+       char *pool_name;
+       char *image_name;
+};
+
+struct rbd_image {
+       char *image_name;
+       struct rbd_image *next;
+};
+struct rbd_image_data {
+    struct rbd_image *images;
+    void *buf;
+};
+struct rbd_image_data rbd_image_data;
+
+struct rbd_openimage {
+       char *image_name;
+       rbd_image_t image;
+       struct rbd_stat rbd_stat;
+};
+#define MAX_RBD_IMAGES         128
+struct rbd_openimage opentbl[MAX_RBD_IMAGES];
+
+struct rbd_options rbd_options = {(char*) "/etc/ceph/ceph.conf", (char*) "rbd",
+                                 NULL};
+
+#define rbdsize(fd)    opentbl[fd].rbd_stat.rbd_info.size
+#define rbdblksize(fd) opentbl[fd].rbd_stat.rbd_info.obj_size
+#define rbdblkcnt(fd)  opentbl[fd].rbd_stat.rbd_info.num_objs
+
+uint64_t imagesize = 1024ULL * 1024 * 1024;
+uint64_t imageorder = 22ULL;
+uint64_t imagefeatures = 1ULL;
+
+// Minimize calls to rbd_list: marks bracketing of opendir/<ops>/releasedir
+int in_opendir;
+
+/* prototypes */
+int connect_to_cluster(rados_t *pcluster);
+void enumerate_images(struct rbd_image_data *data);
+int open_rbd_image(const char *image_name);
+int find_openrbd(const char *path);
+
+void simple_err(const char *msg, int err);
+
+void
+enumerate_images(struct rbd_image_data *data)
+{
+       struct rbd_image **head = &data->images;
+       char *ibuf = NULL;
+       size_t ibuf_len = 0;
+       struct rbd_image *im, *next;
+       char *ip;
+       int ret;
+
+       if (*head != NULL) {
+               for (im = *head; im != NULL;) {
+                       next = im->next;
+                       free(im);
+                       im = next;
+               }
+               *head = NULL;
+               free(data->buf);
+               data->buf = NULL;
+       }
+
+       ret = rbd_list(ioctx, ibuf, &ibuf_len);
+       if (ret == -ERANGE) {
+               assert(ibuf_len > 0);
+               ibuf = (char*) malloc(ibuf_len);
+               if (!ibuf) {
+                       simple_err("Failed to get ibuf", -ENOMEM);
+                       return;
+               }
+       } else if (ret < 0) {
+               simple_err("Failed to get ibuf_len", ret);
+               return;
+       }
+
+       ret = rbd_list(ioctx, ibuf, &ibuf_len);
+       if (ret < 0) {
+               simple_err("Failed to populate ibuf", ret);
+               free(ibuf);
+               return;
+       }
+       assert(ret == (int)ibuf_len);
+
+       fprintf(stderr, "pool %s: ", pool_name);
+       for (ip = ibuf; ip < &ibuf[ibuf_len]; ip += strlen(ip) + 1)  {
+               if ((mount_image_name == NULL) ||
+                   ((strlen(mount_image_name) > 0) &&
+                   (strcmp(ip, mount_image_name) == 0))) {
+                       fprintf(stderr, "%s, ", ip);
+                       im = static_cast<rbd_image*>(malloc(sizeof(*im)));
+                       im->image_name = ip;
+                       im->next = *head;
+                       *head = im;
+               }
+       }
+       fprintf(stderr, "\n");
+       data->buf = ibuf;
+}
+
+int
+find_openrbd(const char *path)
+{
+       int i;
+
+       /* find in opentbl[] entry if already open */
+       for (i = 0; i < MAX_RBD_IMAGES; i++) {
+               if ((opentbl[i].image_name != NULL) &&
+                   (strcmp(opentbl[i].image_name, path) == 0)) {
+                       return i;
+               }
+       }
+       return -1;
+}
+
+int
+open_rbd_image(const char *image_name)
+{
+       struct rbd_image *im;
+       struct rbd_openimage *rbd = NULL;
+       int fd;
+
+       if (image_name == (char *)NULL) 
+               return -1;
+
+       // relies on caller to keep rbd_image_data up to date
+       for (im = rbd_image_data.images; im != NULL; im = im->next) {
+               if (strcmp(im->image_name, image_name) == 0) {
+                       break;
+               }
+       }
+       if (im == NULL)
+               return -1;
+
+       /* find in opentbl[] entry if already open */
+       if ((fd = find_openrbd(image_name)) != -1) {
+               rbd = &opentbl[fd];
+       } else {
+               int i;
+               // allocate an opentbl[] and open the image
+               for (i = 0; i < MAX_RBD_IMAGES; i++) {
+                       if (opentbl[i].image == NULL) {
+                               fd = i;
+                               rbd = &opentbl[fd];
+                               rbd->image_name = strdup(image_name);
+                               break;
+                       }
+               }
+               if (i == MAX_RBD_IMAGES || !rbd)
+                       return -1;
+               int ret = rbd_open(ioctx, rbd->image_name, &(rbd->image), NULL);
+               if (ret < 0) {
+                       simple_err("open_rbd_image: can't open: ", ret);
+                       return ret;
+               }
+       }
+       rbd_stat(rbd->image, &(rbd->rbd_stat.rbd_info),
+                sizeof(rbd_image_info_t));
+       rbd->rbd_stat.valid = 1;
+       return fd;
+}
+
+static void
+iter_images(void *cookie,
+           void (*iter)(void *cookie, const char *image))
+{
+       struct rbd_image *im;
+
+       readdir_lock.lock();
+
+       for (im = rbd_image_data.images; im != NULL; im = im->next)
+               iter(cookie, im->image_name);
+       readdir_lock.unlock();
+}
+
+static void count_images_cb(void *cookie, const char *image)
+{
+       (*((unsigned int *)cookie))++;
+}
+
+static int count_images(void)
+{
+       unsigned int count = 0;
+
+       readdir_lock.lock();
+       enumerate_images(&rbd_image_data);
+       readdir_lock.unlock();
+
+       iter_images(&count, count_images_cb);
+       return count;
+}
+
+extern "C" {
+
+static int rbdfs_getattr(const char *path, struct stat *stbuf)
+{
+       int fd;
+       time_t now;
+
+       if (!gotrados)
+               return -ENXIO;
+
+       if (path[0] == 0)
+               return -ENOENT;
+
+       memset(stbuf, 0, sizeof(struct stat));
+
+       if (strcmp(path, "/") == 0) {
+
+               now = time(NULL);
+               stbuf->st_mode = S_IFDIR + 0755;
+               stbuf->st_nlink = 2+count_images();
+               stbuf->st_uid = getuid();
+               stbuf->st_gid = getgid();
+               stbuf->st_size = 1024;
+               stbuf->st_blksize = 1024;
+               stbuf->st_blocks = 1;
+               stbuf->st_atime = now;
+               stbuf->st_mtime = now;
+               stbuf->st_ctime = now;
+
+               return 0;
+       }
+
+       if (!in_opendir) {
+               readdir_lock.lock();
+               enumerate_images(&rbd_image_data);
+               readdir_lock.unlock();
+       }
+       fd = open_rbd_image(path + 1);
+       if (fd < 0)
+               return -ENOENT;
+
+       now = time(NULL);
+       stbuf->st_mode = S_IFREG | 0666;
+       stbuf->st_nlink = 1;
+       stbuf->st_uid = getuid();
+       stbuf->st_gid = getgid();
+       stbuf->st_size = rbdsize(fd);
+       stbuf->st_blksize = rbdblksize(fd);
+       stbuf->st_blocks = rbdblkcnt(fd);
+       stbuf->st_atime = now;
+       stbuf->st_mtime = now;
+       stbuf->st_ctime = now;
+
+       return 0;
+}
+
+
+static int rbdfs_open(const char *path, struct fuse_file_info *fi)
+{
+       int fd;
+
+       if (!gotrados)
+               return -ENXIO;
+
+       if (path[0] == 0)
+               return -ENOENT;
+
+       readdir_lock.lock();
+       enumerate_images(&rbd_image_data);
+       readdir_lock.unlock();
+       fd = open_rbd_image(path + 1);
+       if (fd < 0)
+               return -ENOENT;
+
+       fi->fh = fd;
+       return 0;
+}
+
+static int rbdfs_read(const char *path, char *buf, size_t size,
+                       off_t offset, struct fuse_file_info *fi)
+{
+       size_t numread;
+       struct rbd_openimage *rbd;
+
+       if (!gotrados)
+               return -ENXIO;
+
+       rbd = &opentbl[fi->fh];
+       numread = 0;
+       while (size > 0) {
+               ssize_t ret;
+
+               ret = rbd_read(rbd->image, offset, size, buf);
+
+               if (ret <= 0)
+                       break;
+               buf += ret;
+               size -= ret;
+               offset += ret;
+               numread += ret;
+       }
+
+       return numread;
+}
+
+static int rbdfs_write(const char *path, const char *buf, size_t size,
+                        off_t offset, struct fuse_file_info *fi)
+{
+       size_t numwritten;
+       struct rbd_openimage *rbd;
+
+       if (!gotrados)
+               return -ENXIO;
+
+       rbd = &opentbl[fi->fh];
+       numwritten = 0;
+       while (size > 0) {
+               ssize_t ret;
+
+               if ((size_t)(offset + size) > rbdsize(fi->fh)) {
+                       int r;
+                       fprintf(stderr, "rbdfs_write resizing %s to 0x%" PRIxMAX "\n",
+                               path, offset+size);
+                       r = rbd_resize(rbd->image, offset+size);
+                       if (r < 0)
+                               return r;
+
+                       r = rbd_stat(rbd->image, &(rbd->rbd_stat.rbd_info),
+                                sizeof(rbd_image_info_t));
+                       if (r < 0)
+                               return r;
+               }
+               ret = rbd_write(rbd->image, offset, size, buf);
+
+               if (ret < 0)
+                       break;
+               buf += ret;
+               size -= ret;
+               offset += ret;
+               numwritten += ret;
+       }
+
+       return numwritten;
+}
+
+static void rbdfs_statfs_image_cb(void *num, const char *image)
+{
+       int     fd;
+
+       ((uint64_t *)num)[0]++;
+
+       fd = open_rbd_image(image);
+       if (fd >= 0)
+               ((uint64_t *)num)[1] += rbdsize(fd);
+}
+
+static int rbdfs_statfs(const char *path, struct statvfs *buf)
+{
+       uint64_t num[2];
+
+       if (!gotrados)
+               return -ENXIO;
+
+       num[0] = 1;
+       num[1] = 0;
+       readdir_lock.lock();
+       enumerate_images(&rbd_image_data);
+       readdir_lock.unlock();
+       iter_images(num, rbdfs_statfs_image_cb);
+
+#define        RBDFS_BSIZE     4096
+       buf->f_bsize = RBDFS_BSIZE;
+       buf->f_frsize = RBDFS_BSIZE;
+       buf->f_blocks = num[1] / RBDFS_BSIZE;
+       buf->f_bfree = 0;
+       buf->f_bavail = 0;
+       buf->f_files = num[0];
+       buf->f_ffree = 0;
+       buf->f_favail = 0;
+       buf->f_fsid = 0;
+       buf->f_flag = 0;
+       buf->f_namemax = PATH_MAX;
+
+       return 0;
+}
+
+static int rbdfs_fsync(const char *path, int datasync,
+                        struct fuse_file_info *fi)
+{
+       if (!gotrados)
+               return -ENXIO;
+       rbd_flush(opentbl[fi->fh].image);
+       return 0;
+}
+
+static int rbdfs_opendir(const char *path, struct fuse_file_info *fi)
+{
+       // only one directory, so global "in_opendir" flag should be fine
+       readdir_lock.lock();
+       in_opendir++;
+       enumerate_images(&rbd_image_data);
+       readdir_lock.unlock();
+       return 0;
+}
+
+struct rbdfs_readdir_info {
+       void *buf;
+       fuse_fill_dir_t filler;
+};
+
+static void rbdfs_readdir_cb(void *_info, const char *name)
+{
+       struct rbdfs_readdir_info *info = (struct rbdfs_readdir_info*) _info;
+
+       info->filler(info->buf, name, NULL, 0);
+}
+
+static int rbdfs_readdir(const char *path, void *buf, fuse_fill_dir_t filler,
+                          off_t offset, struct fuse_file_info *fi)
+{
+       struct rbdfs_readdir_info info = { buf, filler };
+
+       if (!gotrados)
+               return -ENXIO;
+       if (!in_opendir)
+               fprintf(stderr, "in readdir, but not inside opendir?\n");
+
+       if (strcmp(path, "/") != 0)
+               return -ENOENT;
+
+       filler(buf, ".", NULL, 0);
+       filler(buf, "..", NULL, 0);
+       iter_images(&info, rbdfs_readdir_cb);
+
+       return 0;
+}
+static int rbdfs_releasedir(const char *path, struct fuse_file_info *fi)
+{
+       // see opendir comments
+       readdir_lock.lock();
+       in_opendir--;
+       readdir_lock.unlock();
+       return 0;
+}
+
+void *
+rbdfs_init(struct fuse_conn_info *conn)
+{
+       int ret;
+
+       // init cannot fail, so if we fail here, gotrados remains at 0,
+       // causing other operations to fail immediately with ENXIO
+
+       ret = connect_to_cluster(&cluster);
+       if (ret < 0)
+               exit(90);
+
+       pool_name = rbd_options.pool_name;
+       mount_image_name = rbd_options.image_name;
+       ret = rados_ioctx_create(cluster, pool_name, &ioctx);
+       if (ret < 0)
+               exit(91);
+#if FUSE_VERSION >= FUSE_MAKE_VERSION(2, 8)
+       conn->want |= FUSE_CAP_BIG_WRITES;
+#endif
+       gotrados = 1;
+
+       // init's return value shows up in fuse_context.private_data,
+       // also to void (*destroy)(void *); useful?
+       return NULL;
+}
+
+void
+rbdfs_destroy(void *unused)
+{
+       if (!gotrados)
+               return;
+       for (int i = 0; i < MAX_RBD_IMAGES; ++i) {
+               if (opentbl[i].image) {
+                       rbd_close(opentbl[i].image);
+                       opentbl[i].image = NULL;
+               }
+       }
+       rados_ioctx_destroy(ioctx);
+       rados_shutdown(cluster);
+}
+
+int
+rbdfs_checkname(const char *checkname)
+{
+    const char *extra[] = {"@", "/"};
+    std::string strCheckName(checkname);
+    
+    if (strCheckName.empty())
+        return -EINVAL;
+
+    unsigned int sz = sizeof(extra) / sizeof(const char*);
+    for (unsigned int i = 0; i < sz; i++)
+    {
+        std::string ex(extra[i]);
+        if (std::string::npos != strCheckName.find(ex))
+            return -EINVAL;
+    }
+
+    return 0;
+}
+
+// return -errno on error.  fi->fh is not set until open time
+
+int
+rbdfs_create(const char *path, mode_t mode, struct fuse_file_info *fi)
+{
+         int r;
+         int order = imageorder;
+
+         r = rbdfs_checkname(path+1);
+         if (r != 0)
+         {
+            return r;  
+         }
+
+         r = rbd_create2(ioctx, path+1, imagesize, imagefeatures, &order);
+         return r;
+}
+
+int
+rbdfs_rename(const char *path, const char *destname)
+{
+    int r;
+
+    r = rbdfs_checkname(destname+1);
+    if (r != 0)
+    {
+      return r;
+    }
+
+    if (strcmp(path, "/") == 0)
+        return -EINVAL;
+
+    return rbd_rename(ioctx, path+1, destname+1);
+}
+
+int
+rbdfs_utime(const char *path, struct utimbuf *utime)
+{
+       // called on create; not relevant
+       return 0;
+}
+
+int
+rbdfs_unlink(const char *path)
+{
+       int fd = find_openrbd(path+1);
+       if (fd != -1) {
+               struct rbd_openimage *rbd = &opentbl[fd];
+               rbd_close(rbd->image);
+               rbd->image = 0;
+               free(rbd->image_name);
+               rbd->rbd_stat.valid = 0;
+       }
+       return rbd_remove(ioctx, path+1);
+}
+
+
+int
+rbdfs_truncate(const char *path, off_t size)
+{
+       int fd;
+       int r;
+       struct rbd_openimage *rbd;
+
+       if ((fd = open_rbd_image(path+1)) < 0)
+               return -ENOENT;
+
+       rbd = &opentbl[fd];
+       fprintf(stderr, "truncate %s to %" PRIdMAX " (0x%" PRIxMAX ")\n",
+          path, size, size);
+       r = rbd_resize(rbd->image, size);
+       if (r < 0)
+               return r;
+
+       r = rbd_stat(rbd->image, &(rbd->rbd_stat.rbd_info),
+                sizeof(rbd_image_info_t));
+       if (r < 0)
+               return r;
+       return 0;
+}
+
+/**
+ * set an xattr on path, with name/value, length size.
+ * Presumably flags are from Linux, as in XATTR_CREATE or 
+ * XATTR_REPLACE (both "set", but fail if exist vs fail if not exist.
+ *
+ * We accept xattrs only on the root node.
+ *
+ * All values converted with strtoull, so can be expressed in any base
+ */
+
+struct rbdfuse_attr {
+       char *attrname;
+       uint64_t *attrvalp;
+} attrs[] = {
+    { (char*) "user.rbdfuse.imagesize", &imagesize },
+    { (char*) "user.rbdfuse.imageorder", &imageorder },
+    { (char*) "user.rbdfuse.imagefeatures", &imagefeatures },
+    { NULL, NULL }
+};
+
+int
+rbdfs_setxattr(const char *path, const char *name, const char *value,
+              size_t size,
+              int flags
+#if defined(DARWIN)
+              ,uint32_t pos
+#endif
+    )
+{
+       struct rbdfuse_attr *ap;
+       if (strcmp(path, "/") != 0)
+               return -EINVAL;
+
+       for (ap = attrs; ap->attrname != NULL; ap++) {
+               if (strcmp(name, ap->attrname) == 0) {
+                       *ap->attrvalp = strtoull(value, NULL, 0);
+                       fprintf(stderr, "rbd-fuse: %s set to 0x%" PRIx64 "\n",
+                               ap->attrname, *ap->attrvalp);
+                       return 0;
+               }
+       }
+       return -EINVAL;
+}
+
+int
+rbdfs_getxattr(const char *path, const char *name, char *value,
+                size_t size
+#if defined(DARWIN)
+              ,uint32_t position
+#endif
+  )
+{
+       struct rbdfuse_attr *ap;
+       char buf[128];
+       // allow gets on other files; ls likes to ask for things like
+       // security.*
+
+       for (ap = attrs; ap->attrname != NULL; ap++) {
+               if (strcmp(name, ap->attrname) == 0) {
+                       sprintf(buf, "%" PRIu64, *ap->attrvalp);
+                       if (value != NULL && size >= strlen(buf))
+                               strcpy(value, buf);
+                       fprintf(stderr, "rbd-fuse: get %s\n", ap->attrname);
+                       return (strlen(buf));
+               }
+       }
+       return 0;
+}
+
+int
+rbdfs_listxattr(const char *path, char *list, size_t len)
+{
+       struct rbdfuse_attr *ap;
+       size_t required_len = 0;
+
+       if (strcmp(path, "/") != 0)
+               return -EINVAL;
+
+       for (ap = attrs; ap->attrname != NULL; ap++)
+               required_len += strlen(ap->attrname) + 1;
+       if (len >= required_len) {
+               for (ap = attrs; ap->attrname != NULL; ap++) {
+                       sprintf(list, "%s", ap->attrname);
+                       list += strlen(ap->attrname) + 1;
+               }
+       }
+       return required_len;
+}
+
+const static struct fuse_operations rbdfs_oper = {
+  getattr:    rbdfs_getattr,
+  readlink:   0,
+  getdir:     0,
+  mknod:      0,
+  mkdir:      0,
+  unlink:     rbdfs_unlink,
+  rmdir:      0,
+  symlink:    0,
+  rename:     rbdfs_rename,
+  link:       0,
+  chmod:      0,
+  chown:      0,
+  truncate:   rbdfs_truncate,
+  utime:      rbdfs_utime,
+  open:              rbdfs_open,
+  read:              rbdfs_read,
+  write:      rbdfs_write,
+  statfs:     rbdfs_statfs,
+  flush:      0,
+  release:    0,
+  fsync:      rbdfs_fsync,
+  setxattr:   rbdfs_setxattr,
+  getxattr:   rbdfs_getxattr,
+  listxattr:  rbdfs_listxattr,
+  removexattr: 0,
+  opendir:    rbdfs_opendir,
+  readdir:    rbdfs_readdir,
+  releasedir: rbdfs_releasedir,
+  fsyncdir:   0,
+  init:              rbdfs_init,
+  destroy:    rbdfs_destroy,
+  access:     0,
+  create:     rbdfs_create,
+  /* skip unimplemented */
+};
+
+} /* extern "C" */
+
+enum {
+       KEY_HELP,
+       KEY_VERSION,
+       KEY_CEPH_CONFIG,
+       KEY_CEPH_CONFIG_LONG,
+       KEY_RADOS_POOLNAME,
+       KEY_RADOS_POOLNAME_LONG,
+       KEY_RBD_IMAGENAME,
+       KEY_RBD_IMAGENAME_LONG
+};
+
+static struct fuse_opt rbdfs_opts[] = {
+       FUSE_OPT_KEY("-h", KEY_HELP),
+       FUSE_OPT_KEY("--help", KEY_HELP),
+       FUSE_OPT_KEY("-V", KEY_VERSION),
+       FUSE_OPT_KEY("--version", KEY_VERSION),
+       {"-c %s", offsetof(struct rbd_options, ceph_config), KEY_CEPH_CONFIG},
+       {"--configfile=%s", offsetof(struct rbd_options, ceph_config),
+        KEY_CEPH_CONFIG_LONG},
+       {"-p %s", offsetof(struct rbd_options, pool_name), KEY_RADOS_POOLNAME},
+       {"--poolname=%s", offsetof(struct rbd_options, pool_name),
+        KEY_RADOS_POOLNAME_LONG},
+       {"-r %s", offsetof(struct rbd_options, image_name), KEY_RBD_IMAGENAME},
+       {"--image=%s", offsetof(struct rbd_options, image_name),
+       KEY_RBD_IMAGENAME_LONG},
+};
+
+static void usage(const char *progname)
+{
+       fprintf(stderr,
+"Usage: %s mountpoint [options]\n"
+"\n"
+"General options:\n"
+"    -h   --help            print help\n"
+"    -V   --version         print version\n"
+"    -c   --configfile      ceph configuration file [/etc/ceph/ceph.conf]\n"
+"    -p   --poolname        rados pool name [rbd]\n"
+"    -r   --image           RBD image name\n"
+"\n", progname);
+}
+
+static int rbdfs_opt_proc(void *data, const char *arg, int key,
+                           struct fuse_args *outargs)
+{
+       if (key == KEY_HELP) {
+               usage(outargs->argv[0]);
+               fuse_opt_add_arg(outargs, "-ho");
+               fuse_main(outargs->argc, outargs->argv, &rbdfs_oper, NULL);
+               exit(1);
+       }
+
+       if (key == KEY_VERSION) {
+               fuse_opt_add_arg(outargs, "--version");
+               fuse_main(outargs->argc, outargs->argv, &rbdfs_oper, NULL);
+               exit(0);
+       }
+
+       if (key == KEY_CEPH_CONFIG) {
+               if (rbd_options.ceph_config != NULL) {
+                       free(rbd_options.ceph_config);
+                       rbd_options.ceph_config = NULL;
+               }
+               rbd_options.ceph_config = strdup(arg+2);
+               return 0;
+       }
+
+       if (key == KEY_RADOS_POOLNAME) {
+               if (rbd_options.pool_name != NULL) {
+                       free(rbd_options.pool_name);
+                       rbd_options.pool_name = NULL;
+               }
+               rbd_options.pool_name = strdup(arg+2);
+               return 0;
+       }
+
+       if (key == KEY_RBD_IMAGENAME) {
+               if (rbd_options.image_name!= NULL) {
+                       free(rbd_options.image_name);
+                       rbd_options.image_name = NULL;
+               }
+               rbd_options.image_name = strdup(arg+2);
+               return 0;
+       }
+
+       return 1;
+}
+
+void
+simple_err(const char *msg, int err)
+{
+       fprintf(stderr, "%s: %s\n", msg, strerror(-err));
+       return;
+}
+
+int
+connect_to_cluster(rados_t *pcluster)
+{
+       int r;
+
+       r = rados_create(pcluster, NULL);
+       if (r < 0) {
+               simple_err("Could not create cluster handle", r);
+               return r;
+       }
+       rados_conf_parse_env(*pcluster, NULL);
+       r = rados_conf_read_file(*pcluster, rbd_options.ceph_config);
+       if (r < 0) {
+               simple_err("Error reading Ceph config file", r);
+               goto failed_shutdown;
+       }
+       r = rados_connect(*pcluster);
+       if (r < 0) {
+               simple_err("Error connecting to cluster", r);
+               goto failed_shutdown;
+       }
+
+       return 0;
+
+failed_shutdown:
+       rados_shutdown(*pcluster);
+       return r;
+}
+
+int main(int argc, char *argv[])
+{
+       struct fuse_args args = FUSE_ARGS_INIT(argc, argv);
+
+       if (fuse_opt_parse(&args, &rbd_options, rbdfs_opts, rbdfs_opt_proc) == -1) {
+               exit(1);
+       }
+
+       return fuse_main(args.argc, args.argv, &rbdfs_oper, NULL);
+}