Initial import

1 files changed, 1059 insertions, 0 deletions

diff --git a/fs/ceph/super.c b/fs/ceph/super.c
new file mode 100644
index 000000000..4e9905374
--- /dev/null
+++ b/fs/ceph/super.c
@@ -0,0 +1,1059 @@
+
+#include <linux/ceph/ceph_debug.h>
+
+#include <linux/backing-dev.h>
+#include <linux/ctype.h>
+#include <linux/fs.h>
+#include <linux/inet.h>
+#include <linux/in6.h>
+#include <linux/module.h>
+#include <linux/mount.h>
+#include <linux/parser.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/statfs.h>
+#include <linux/string.h>
+
+#include "super.h"
+#include "mds_client.h"
+#include "cache.h"
+
+#include <linux/ceph/ceph_features.h>
+#include <linux/ceph/decode.h>
+#include <linux/ceph/mon_client.h>
+#include <linux/ceph/auth.h>
+#include <linux/ceph/debugfs.h>
+
+/*
+ * Ceph superblock operations
+ *
+ * Handle the basics of mounting, unmounting.
+ */
+
+/*
+ * super ops
+ */
+static void ceph_put_super(struct super_block *s)
+{
+	struct ceph_fs_client *fsc = ceph_sb_to_client(s);
+
+	dout("put_super\n");
+	ceph_mdsc_close_sessions(fsc->mdsc);
+}
+
+static int ceph_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct ceph_fs_client *fsc = ceph_inode_to_client(d_inode(dentry));
+	struct ceph_monmap *monmap = fsc->client->monc.monmap;
+	struct ceph_statfs st;
+	u64 fsid;
+	int err;
+
+	dout("statfs\n");
+	err = ceph_monc_do_statfs(&fsc->client->monc, &st);
+	if (err < 0)
+		return err;
+
+	/* fill in kstatfs */
+	buf->f_type = CEPH_SUPER_MAGIC;  /* ?? */
+
+	/*
+	 * express utilization in terms of large blocks to avoid
+	 * overflow on 32-bit machines.
+	 *
+	 * NOTE: for the time being, we make bsize == frsize to humor
+	 * not-yet-ancient versions of glibc that are broken.
+	 * Someday, we will probably want to report a real block
+	 * size...  whatever that may mean for a network file system!
+	 */
+	buf->f_bsize = 1 << CEPH_BLOCK_SHIFT;
+	buf->f_frsize = 1 << CEPH_BLOCK_SHIFT;
+	buf->f_blocks = le64_to_cpu(st.kb) >> (CEPH_BLOCK_SHIFT-10);
+	buf->f_bfree = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
+	buf->f_bavail = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
+
+	buf->f_files = le64_to_cpu(st.num_objects);
+	buf->f_ffree = -1;
+	buf->f_namelen = NAME_MAX;
+
+	/* leave fsid little-endian, regardless of host endianness */
+	fsid = *(u64 *)(&monmap->fsid) ^ *((u64 *)&monmap->fsid + 1);
+	buf->f_fsid.val[0] = fsid & 0xffffffff;
+	buf->f_fsid.val[1] = fsid >> 32;
+
+	return 0;
+}
+
+
+static int ceph_sync_fs(struct super_block *sb, int wait)
+{
+	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
+
+	if (!wait) {
+		dout("sync_fs (non-blocking)\n");
+		ceph_flush_dirty_caps(fsc->mdsc);
+		dout("sync_fs (non-blocking) done\n");
+		return 0;
+	}
+
+	dout("sync_fs (blocking)\n");
+	ceph_osdc_sync(&fsc->client->osdc);
+	ceph_mdsc_sync(fsc->mdsc);
+	dout("sync_fs (blocking) done\n");
+	return 0;
+}
+
+/*
+ * mount options
+ */
+enum {
+	Opt_wsize,
+	Opt_rsize,
+	Opt_rasize,
+	Opt_caps_wanted_delay_min,
+	Opt_caps_wanted_delay_max,
+	Opt_cap_release_safety,
+	Opt_readdir_max_entries,
+	Opt_readdir_max_bytes,
+	Opt_congestion_kb,
+	Opt_last_int,
+	/* int args above */
+	Opt_snapdirname,
+	Opt_last_string,
+	/* string args above */
+	Opt_dirstat,
+	Opt_nodirstat,
+	Opt_rbytes,
+	Opt_norbytes,
+	Opt_asyncreaddir,
+	Opt_noasyncreaddir,
+	Opt_dcache,
+	Opt_nodcache,
+	Opt_ino32,
+	Opt_noino32,
+	Opt_fscache,
+	Opt_nofscache,
+#ifdef CONFIG_CEPH_FS_POSIX_ACL
+	Opt_acl,
+#endif
+	Opt_noacl
+};
+
+static match_table_t fsopt_tokens = {
+	{Opt_wsize, "wsize=%d"},
+	{Opt_rsize, "rsize=%d"},
+	{Opt_rasize, "rasize=%d"},
+	{Opt_caps_wanted_delay_min, "caps_wanted_delay_min=%d"},
+	{Opt_caps_wanted_delay_max, "caps_wanted_delay_max=%d"},
+	{Opt_cap_release_safety, "cap_release_safety=%d"},
+	{Opt_readdir_max_entries, "readdir_max_entries=%d"},
+	{Opt_readdir_max_bytes, "readdir_max_bytes=%d"},
+	{Opt_congestion_kb, "write_congestion_kb=%d"},
+	/* int args above */
+	{Opt_snapdirname, "snapdirname=%s"},
+	/* string args above */
+	{Opt_dirstat, "dirstat"},
+	{Opt_nodirstat, "nodirstat"},
+	{Opt_rbytes, "rbytes"},
+	{Opt_norbytes, "norbytes"},
+	{Opt_asyncreaddir, "asyncreaddir"},
+	{Opt_noasyncreaddir, "noasyncreaddir"},
+	{Opt_dcache, "dcache"},
+	{Opt_nodcache, "nodcache"},
+	{Opt_ino32, "ino32"},
+	{Opt_noino32, "noino32"},
+	{Opt_fscache, "fsc"},
+	{Opt_nofscache, "nofsc"},
+#ifdef CONFIG_CEPH_FS_POSIX_ACL
+	{Opt_acl, "acl"},
+#endif
+	{Opt_noacl, "noacl"},
+	{-1, NULL}
+};
+
+static int parse_fsopt_token(char *c, void *private)
+{
+	struct ceph_mount_options *fsopt = private;
+	substring_t argstr[MAX_OPT_ARGS];
+	int token, intval, ret;
+
+	token = match_token((char *)c, fsopt_tokens, argstr);
+	if (token < 0)
+		return -EINVAL;
+
+	if (token < Opt_last_int) {
+		ret = match_int(&argstr[0], &intval);
+		if (ret < 0) {
+			pr_err("bad mount option arg (not int) "
+			       "at '%s'\n", c);
+			return ret;
+		}
+		dout("got int token %d val %d\n", token, intval);
+	} else if (token > Opt_last_int && token < Opt_last_string) {
+		dout("got string token %d val %s\n", token,
+		     argstr[0].from);
+	} else {
+		dout("got token %d\n", token);
+	}
+
+	switch (token) {
+	case Opt_snapdirname:
+		kfree(fsopt->snapdir_name);
+		fsopt->snapdir_name = kstrndup(argstr[0].from,
+					       argstr[0].to-argstr[0].from,
+					       GFP_KERNEL);
+		if (!fsopt->snapdir_name)
+			return -ENOMEM;
+		break;
+
+		/* misc */
+	case Opt_wsize:
+		fsopt->wsize = intval;
+		break;
+	case Opt_rsize:
+		fsopt->rsize = intval;
+		break;
+	case Opt_rasize:
+		fsopt->rasize = intval;
+		break;
+	case Opt_caps_wanted_delay_min:
+		fsopt->caps_wanted_delay_min = intval;
+		break;
+	case Opt_caps_wanted_delay_max:
+		fsopt->caps_wanted_delay_max = intval;
+		break;
+	case Opt_readdir_max_entries:
+		fsopt->max_readdir = intval;
+		break;
+	case Opt_readdir_max_bytes:
+		fsopt->max_readdir_bytes = intval;
+		break;
+	case Opt_congestion_kb:
+		fsopt->congestion_kb = intval;
+		break;
+	case Opt_dirstat:
+		fsopt->flags |= CEPH_MOUNT_OPT_DIRSTAT;
+		break;
+	case Opt_nodirstat:
+		fsopt->flags &= ~CEPH_MOUNT_OPT_DIRSTAT;
+		break;
+	case Opt_rbytes:
+		fsopt->flags |= CEPH_MOUNT_OPT_RBYTES;
+		break;
+	case Opt_norbytes:
+		fsopt->flags &= ~CEPH_MOUNT_OPT_RBYTES;
+		break;
+	case Opt_asyncreaddir:
+		fsopt->flags &= ~CEPH_MOUNT_OPT_NOASYNCREADDIR;
+		break;
+	case Opt_noasyncreaddir:
+		fsopt->flags |= CEPH_MOUNT_OPT_NOASYNCREADDIR;
+		break;
+	case Opt_dcache:
+		fsopt->flags |= CEPH_MOUNT_OPT_DCACHE;
+		break;
+	case Opt_nodcache:
+		fsopt->flags &= ~CEPH_MOUNT_OPT_DCACHE;
+		break;
+	case Opt_ino32:
+		fsopt->flags |= CEPH_MOUNT_OPT_INO32;
+		break;
+	case Opt_noino32:
+		fsopt->flags &= ~CEPH_MOUNT_OPT_INO32;
+		break;
+	case Opt_fscache:
+		fsopt->flags |= CEPH_MOUNT_OPT_FSCACHE;
+		break;
+	case Opt_nofscache:
+		fsopt->flags &= ~CEPH_MOUNT_OPT_FSCACHE;
+		break;
+#ifdef CONFIG_CEPH_FS_POSIX_ACL
+	case Opt_acl:
+		fsopt->sb_flags |= MS_POSIXACL;
+		break;
+#endif
+	case Opt_noacl:
+		fsopt->sb_flags &= ~MS_POSIXACL;
+		break;
+	default:
+		BUG_ON(token);
+	}
+	return 0;
+}
+
+static void destroy_mount_options(struct ceph_mount_options *args)
+{
+	dout("destroy_mount_options %p\n", args);
+	kfree(args->snapdir_name);
+	kfree(args);
+}
+
+static int strcmp_null(const char *s1, const char *s2)
+{
+	if (!s1 && !s2)
+		return 0;
+	if (s1 && !s2)
+		return -1;
+	if (!s1 && s2)
+		return 1;
+	return strcmp(s1, s2);
+}
+
+static int compare_mount_options(struct ceph_mount_options *new_fsopt,
+				 struct ceph_options *new_opt,
+				 struct ceph_fs_client *fsc)
+{
+	struct ceph_mount_options *fsopt1 = new_fsopt;
+	struct ceph_mount_options *fsopt2 = fsc->mount_options;
+	int ofs = offsetof(struct ceph_mount_options, snapdir_name);
+	int ret;
+
+	ret = memcmp(fsopt1, fsopt2, ofs);
+	if (ret)
+		return ret;
+
+	ret = strcmp_null(fsopt1->snapdir_name, fsopt2->snapdir_name);
+	if (ret)
+		return ret;
+
+	return ceph_compare_options(new_opt, fsc->client);
+}
+
+static int parse_mount_options(struct ceph_mount_options **pfsopt,
+			       struct ceph_options **popt,
+			       int flags, char *options,
+			       const char *dev_name,
+			       const char **path)
+{
+	struct ceph_mount_options *fsopt;
+	const char *dev_name_end;
+	int err;
+
+	if (!dev_name || !*dev_name)
+		return -EINVAL;
+
+	fsopt = kzalloc(sizeof(*fsopt), GFP_KERNEL);
+	if (!fsopt)
+		return -ENOMEM;
+
+	dout("parse_mount_options %p, dev_name '%s'\n", fsopt, dev_name);
+
+	fsopt->sb_flags = flags;
+	fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
+
+	fsopt->rsize = CEPH_RSIZE_DEFAULT;
+	fsopt->rasize = CEPH_RASIZE_DEFAULT;
+	fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
+	if (!fsopt->snapdir_name) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
+	fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
+	fsopt->cap_release_safety = CEPH_CAP_RELEASE_SAFETY_DEFAULT;
+	fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
+	fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
+	fsopt->congestion_kb = default_congestion_kb();
+
+	/*
+	 * Distinguish the server list from the path in "dev_name".
+	 * Internally we do not include the leading '/' in the path.
+	 *
+	 * "dev_name" will look like:
+	 *     <server_spec>[,<server_spec>...]:[<path>]
+	 * where
+	 *     <server_spec> is <ip>[:<port>]
+	 *     <path> is optional, but if present must begin with '/'
+	 */
+	dev_name_end = strchr(dev_name, '/');
+	if (dev_name_end) {
+		/* skip over leading '/' for path */
+		*path = dev_name_end + 1;
+	} else {
+		/* path is empty */
+		dev_name_end = dev_name + strlen(dev_name);
+		*path = dev_name_end;
+	}
+	err = -EINVAL;
+	dev_name_end--;		/* back up to ':' separator */
+	if (dev_name_end < dev_name || *dev_name_end != ':') {
+		pr_err("device name is missing path (no : separator in %s)\n",
+				dev_name);
+		goto out;
+	}
+	dout("device name '%.*s'\n", (int)(dev_name_end - dev_name), dev_name);
+	dout("server path '%s'\n", *path);
+
+	*popt = ceph_parse_options(options, dev_name, dev_name_end,
+				 parse_fsopt_token, (void *)fsopt);
+	if (IS_ERR(*popt)) {
+		err = PTR_ERR(*popt);
+		goto out;
+	}
+
+	/* success */
+	*pfsopt = fsopt;
+	return 0;
+
+out:
+	destroy_mount_options(fsopt);
+	return err;
+}
+
+/**
+ * ceph_show_options - Show mount options in /proc/mounts
+ * @m: seq_file to write to
+ * @root: root of that (sub)tree
+ */
+static int ceph_show_options(struct seq_file *m, struct dentry *root)
+{
+	struct ceph_fs_client *fsc = ceph_sb_to_client(root->d_sb);
+	struct ceph_mount_options *fsopt = fsc->mount_options;
+	size_t pos;
+	int ret;
+
+	/* a comma between MNT/MS and client options */
+	seq_putc(m, ',');
+	pos = m->count;
+
+	ret = ceph_print_client_options(m, fsc->client);
+	if (ret)
+		return ret;
+
+	/* retract our comma if no client options */
+	if (m->count == pos)
+		m->count--;
+
+	if (fsopt->flags & CEPH_MOUNT_OPT_DIRSTAT)
+		seq_puts(m, ",dirstat");
+	if ((fsopt->flags & CEPH_MOUNT_OPT_RBYTES) == 0)
+		seq_puts(m, ",norbytes");
+	if (fsopt->flags & CEPH_MOUNT_OPT_NOASYNCREADDIR)
+		seq_puts(m, ",noasyncreaddir");
+	if ((fsopt->flags & CEPH_MOUNT_OPT_DCACHE) == 0)
+		seq_puts(m, ",nodcache");
+	if (fsopt->flags & CEPH_MOUNT_OPT_FSCACHE)
+		seq_puts(m, ",fsc");
+
+#ifdef CONFIG_CEPH_FS_POSIX_ACL
+	if (fsopt->sb_flags & MS_POSIXACL)
+		seq_puts(m, ",acl");
+	else
+		seq_puts(m, ",noacl");
+#endif
+
+	if (fsopt->wsize)
+		seq_printf(m, ",wsize=%d", fsopt->wsize);
+	if (fsopt->rsize != CEPH_RSIZE_DEFAULT)
+		seq_printf(m, ",rsize=%d", fsopt->rsize);
+	if (fsopt->rasize != CEPH_RASIZE_DEFAULT)
+		seq_printf(m, ",rasize=%d", fsopt->rasize);
+	if (fsopt->congestion_kb != default_congestion_kb())
+		seq_printf(m, ",write_congestion_kb=%d", fsopt->congestion_kb);
+	if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
+		seq_printf(m, ",caps_wanted_delay_min=%d",
+			 fsopt->caps_wanted_delay_min);
+	if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
+		seq_printf(m, ",caps_wanted_delay_max=%d",
+			   fsopt->caps_wanted_delay_max);
+	if (fsopt->cap_release_safety != CEPH_CAP_RELEASE_SAFETY_DEFAULT)
+		seq_printf(m, ",cap_release_safety=%d",
+			   fsopt->cap_release_safety);
+	if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
+		seq_printf(m, ",readdir_max_entries=%d", fsopt->max_readdir);
+	if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
+		seq_printf(m, ",readdir_max_bytes=%d", fsopt->max_readdir_bytes);
+	if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
+		seq_printf(m, ",snapdirname=%s", fsopt->snapdir_name);
+
+	return 0;
+}
+
+/*
+ * handle any mon messages the standard library doesn't understand.
+ * return error if we don't either.
+ */
+static int extra_mon_dispatch(struct ceph_client *client, struct ceph_msg *msg)
+{
+	struct ceph_fs_client *fsc = client->private;
+	int type = le16_to_cpu(msg->hdr.type);
+
+	switch (type) {
+	case CEPH_MSG_MDS_MAP:
+		ceph_mdsc_handle_map(fsc->mdsc, msg);
+		return 0;
+
+	default:
+		return -1;
+	}
+}
+
+/*
+ * create a new fs client
+ */
+static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
+					struct ceph_options *opt)
+{
+	struct ceph_fs_client *fsc;
+	const u64 supported_features =
+		CEPH_FEATURE_FLOCK |
+		CEPH_FEATURE_DIRLAYOUTHASH |
+		CEPH_FEATURE_MDS_INLINE_DATA;
+	const u64 required_features = 0;
+	int page_count;
+	size_t size;
+	int err = -ENOMEM;
+
+	fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
+	if (!fsc)
+		return ERR_PTR(-ENOMEM);
+
+	fsc->client = ceph_create_client(opt, fsc, supported_features,
+					 required_features);
+	if (IS_ERR(fsc->client)) {
+		err = PTR_ERR(fsc->client);
+		goto fail;
+	}
+	fsc->client->extra_mon_dispatch = extra_mon_dispatch;
+	fsc->client->monc.want_mdsmap = 1;
+
+	fsc->mount_options = fsopt;
+
+	fsc->sb = NULL;
+	fsc->mount_state = CEPH_MOUNT_MOUNTING;
+
+	atomic_long_set(&fsc->writeback_count, 0);
+
+	err = bdi_init(&fsc->backing_dev_info);
+	if (err < 0)
+		goto fail_client;
+
+	err = -ENOMEM;
+	/*
+	 * The number of concurrent works can be high but they don't need
+	 * to be processed in parallel, limit concurrency.
+	 */
+	fsc->wb_wq = alloc_workqueue("ceph-writeback", 0, 1);
+	if (fsc->wb_wq == NULL)
+		goto fail_bdi;
+	fsc->pg_inv_wq = alloc_workqueue("ceph-pg-invalid", 0, 1);
+	if (fsc->pg_inv_wq == NULL)
+		goto fail_wb_wq;
+	fsc->trunc_wq = alloc_workqueue("ceph-trunc", 0, 1);
+	if (fsc->trunc_wq == NULL)
+		goto fail_pg_inv_wq;
+
+	/* set up mempools */
+	err = -ENOMEM;
+	page_count = fsc->mount_options->wsize >> PAGE_CACHE_SHIFT;
+	size = sizeof (struct page *) * (page_count ? page_count : 1);
+	fsc->wb_pagevec_pool = mempool_create_kmalloc_pool(10, size);
+	if (!fsc->wb_pagevec_pool)
+		goto fail_trunc_wq;
+
+	/* setup fscache */
+	if ((fsopt->flags & CEPH_MOUNT_OPT_FSCACHE) &&
+	    (ceph_fscache_register_fs(fsc) != 0))
+		goto fail_fscache;
+
+	/* caps */
+	fsc->min_caps = fsopt->max_readdir;
+
+	return fsc;
+
+fail_fscache:
+	ceph_fscache_unregister_fs(fsc);
+fail_trunc_wq:
+	destroy_workqueue(fsc->trunc_wq);
+fail_pg_inv_wq:
+	destroy_workqueue(fsc->pg_inv_wq);
+fail_wb_wq:
+	destroy_workqueue(fsc->wb_wq);
+fail_bdi:
+	bdi_destroy(&fsc->backing_dev_info);
+fail_client:
+	ceph_destroy_client(fsc->client);
+fail:
+	kfree(fsc);
+	return ERR_PTR(err);
+}
+
+static void destroy_fs_client(struct ceph_fs_client *fsc)
+{
+	dout("destroy_fs_client %p\n", fsc);
+
+	ceph_fscache_unregister_fs(fsc);
+
+	destroy_workqueue(fsc->wb_wq);
+	destroy_workqueue(fsc->pg_inv_wq);
+	destroy_workqueue(fsc->trunc_wq);
+
+	bdi_destroy(&fsc->backing_dev_info);
+
+	mempool_destroy(fsc->wb_pagevec_pool);
+
+	destroy_mount_options(fsc->mount_options);
+
+	ceph_fs_debugfs_cleanup(fsc);
+
+	ceph_destroy_client(fsc->client);
+
+	kfree(fsc);
+	dout("destroy_fs_client %p done\n", fsc);
+}
+
+/*
+ * caches
+ */
+struct kmem_cache *ceph_inode_cachep;
+struct kmem_cache *ceph_cap_cachep;
+struct kmem_cache *ceph_dentry_cachep;
+struct kmem_cache *ceph_file_cachep;
+
+static void ceph_inode_init_once(void *foo)
+{
+	struct ceph_inode_info *ci = foo;
+	inode_init_once(&ci->vfs_inode);
+}
+
+static int __init init_caches(void)
+{
+	int error = -ENOMEM;
+
+	ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
+				      sizeof(struct ceph_inode_info),
+				      __alignof__(struct ceph_inode_info),
+				      (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD),
+				      ceph_inode_init_once);
+	if (ceph_inode_cachep == NULL)
+		return -ENOMEM;
+
+	ceph_cap_cachep = KMEM_CACHE(ceph_cap,
+				     SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
+	if (ceph_cap_cachep == NULL)
+		goto bad_cap;
+
+	ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
+					SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
+	if (ceph_dentry_cachep == NULL)
+		goto bad_dentry;
+
+	ceph_file_cachep = KMEM_CACHE(ceph_file_info,
+				      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
+	if (ceph_file_cachep == NULL)
+		goto bad_file;
+
+	if ((error = ceph_fscache_register()))
+		goto bad_file;
+
+	return 0;
+bad_file:
+	kmem_cache_destroy(ceph_dentry_cachep);
+bad_dentry:
+	kmem_cache_destroy(ceph_cap_cachep);
+bad_cap:
+	kmem_cache_destroy(ceph_inode_cachep);
+	return error;
+}
+
+static void destroy_caches(void)
+{
+	/*
+	 * Make sure all delayed rcu free inodes are flushed before we
+	 * destroy cache.
+	 */
+	rcu_barrier();
+
+	kmem_cache_destroy(ceph_inode_cachep);
+	kmem_cache_destroy(ceph_cap_cachep);
+	kmem_cache_destroy(ceph_dentry_cachep);
+	kmem_cache_destroy(ceph_file_cachep);
+
+	ceph_fscache_unregister();
+}
+
+
+/*
+ * ceph_umount_begin - initiate forced umount.  Tear down down the
+ * mount, skipping steps that may hang while waiting for server(s).
+ */
+static void ceph_umount_begin(struct super_block *sb)
+{
+	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
+
+	dout("ceph_umount_begin - starting forced umount\n");
+	if (!fsc)
+		return;
+	fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
+	return;
+}
+
+static const struct super_operations ceph_super_ops = {
+	.alloc_inode	= ceph_alloc_inode,
+	.destroy_inode	= ceph_destroy_inode,
+	.write_inode    = ceph_write_inode,
+	.drop_inode	= ceph_drop_inode,
+	.sync_fs        = ceph_sync_fs,
+	.put_super	= ceph_put_super,
+	.show_options   = ceph_show_options,
+	.statfs		= ceph_statfs,
+	.umount_begin   = ceph_umount_begin,
+};
+
+/*
+ * Bootstrap mount by opening the root directory.  Note the mount
+ * @started time from caller, and time out if this takes too long.
+ */
+static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
+				       const char *path,
+				       unsigned long started)
+{
+	struct ceph_mds_client *mdsc = fsc->mdsc;
+	struct ceph_mds_request *req = NULL;
+	int err;
+	struct dentry *root;
+
+	/* open dir */
+	dout("open_root_inode opening '%s'\n", path);
+	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
+	if (IS_ERR(req))
+		return ERR_CAST(req);
+	req->r_path1 = kstrdup(path, GFP_NOFS);
+	if (!req->r_path1) {
+		root = ERR_PTR(-ENOMEM);
+		goto out;
+	}
+
+	req->r_ino1.ino = CEPH_INO_ROOT;
+	req->r_ino1.snap = CEPH_NOSNAP;
+	req->r_started = started;
+	req->r_timeout = fsc->client->options->mount_timeout * HZ;
+	req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
+	req->r_num_caps = 2;
+	err = ceph_mdsc_do_request(mdsc, NULL, req);
+	if (err == 0) {
+		struct inode *inode = req->r_target_inode;
+		req->r_target_inode = NULL;
+		dout("open_root_inode success\n");
+		if (ceph_ino(inode) == CEPH_INO_ROOT &&
+		    fsc->sb->s_root == NULL) {
+			root = d_make_root(inode);
+			if (!root) {
+				root = ERR_PTR(-ENOMEM);
+				goto out;
+			}
+		} else {
+			root = d_obtain_root(inode);
+		}
+		ceph_init_dentry(root);
+		dout("open_root_inode success, root dentry is %p\n", root);
+	} else {
+		root = ERR_PTR(err);
+	}
+out:
+	ceph_mdsc_put_request(req);
+	return root;
+}
+
+
+
+
+/*
+ * mount: join the ceph cluster, and open root directory.
+ */
+static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
+		      const char *path)
+{
+	int err;
+	unsigned long started = jiffies;  /* note the start time */
+	struct dentry *root;
+	int first = 0;   /* first vfsmount for this super_block */
+
+	dout("mount start\n");
+	mutex_lock(&fsc->client->mount_mutex);
+
+	err = __ceph_open_session(fsc->client, started);
+	if (err < 0)
+		goto out;
+
+	dout("mount opening root\n");
+	root = open_root_dentry(fsc, "", started);
+	if (IS_ERR(root)) {
+		err = PTR_ERR(root);
+		goto out;
+	}
+	if (fsc->sb->s_root) {
+		dput(root);
+	} else {
+		fsc->sb->s_root = root;
+		first = 1;
+
+		err = ceph_fs_debugfs_init(fsc);
+		if (err < 0)
+			goto fail;
+	}
+
+	if (path[0] == 0) {
+		dget(root);
+	} else {
+		dout("mount opening base mountpoint\n");
+		root = open_root_dentry(fsc, path, started);
+		if (IS_ERR(root)) {
+			err = PTR_ERR(root);
+			goto fail;
+		}
+	}
+
+	fsc->mount_state = CEPH_MOUNT_MOUNTED;
+	dout("mount success\n");
+	mutex_unlock(&fsc->client->mount_mutex);
+	return root;
+
+out:
+	mutex_unlock(&fsc->client->mount_mutex);
+	return ERR_PTR(err);
+
+fail:
+	if (first) {
+		dput(fsc->sb->s_root);
+		fsc->sb->s_root = NULL;
+	}
+	goto out;
+}
+
+static int ceph_set_super(struct super_block *s, void *data)
+{
+	struct ceph_fs_client *fsc = data;
+	int ret;
+
+	dout("set_super %p data %p\n", s, data);
+
+	s->s_flags = fsc->mount_options->sb_flags;
+	s->s_maxbytes = 1ULL << 40;  /* temp value until we get mdsmap */
+
+	s->s_xattr = ceph_xattr_handlers;
+	s->s_fs_info = fsc;
+	fsc->sb = s;
+
+	s->s_op = &ceph_super_ops;
+	s->s_export_op = &ceph_export_ops;
+
+	s->s_time_gran = 1000;  /* 1000 ns == 1 us */
+
+	ret = set_anon_super(s, NULL);  /* what is that second arg for? */
+	if (ret != 0)
+		goto fail;
+
+	return ret;
+
+fail:
+	s->s_fs_info = NULL;
+	fsc->sb = NULL;
+	return ret;
+}
+
+/*
+ * share superblock if same fs AND options
+ */
+static int ceph_compare_super(struct super_block *sb, void *data)
+{
+	struct ceph_fs_client *new = data;
+	struct ceph_mount_options *fsopt = new->mount_options;
+	struct ceph_options *opt = new->client->options;
+	struct ceph_fs_client *other = ceph_sb_to_client(sb);
+
+	dout("ceph_compare_super %p\n", sb);
+
+	if (compare_mount_options(fsopt, opt, other)) {
+		dout("monitor(s)/mount options don't match\n");
+		return 0;
+	}
+	if ((opt->flags & CEPH_OPT_FSID) &&
+	    ceph_fsid_compare(&opt->fsid, &other->client->fsid)) {
+		dout("fsid doesn't match\n");
+		return 0;
+	}
+	if (fsopt->sb_flags != other->mount_options->sb_flags) {
+		dout("flags differ\n");
+		return 0;
+	}
+	return 1;
+}
+
+/*
+ * construct our own bdi so we can control readahead, etc.
+ */
+static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
+
+static int ceph_register_bdi(struct super_block *sb,
+			     struct ceph_fs_client *fsc)
+{
+	int err;
+
+	/* set ra_pages based on rasize mount option? */
+	if (fsc->mount_options->rasize >= PAGE_CACHE_SIZE)
+		fsc->backing_dev_info.ra_pages =
+			(fsc->mount_options->rasize + PAGE_CACHE_SIZE - 1)
+			>> PAGE_SHIFT;
+	else
+		fsc->backing_dev_info.ra_pages =
+			VM_MAX_READAHEAD * 1024 / PAGE_CACHE_SIZE;
+
+	err = bdi_register(&fsc->backing_dev_info, NULL, "ceph-%ld",
+			   atomic_long_inc_return(&bdi_seq));
+	if (!err)
+		sb->s_bdi = &fsc->backing_dev_info;
+	return err;
+}
+
+static struct dentry *ceph_mount(struct file_system_type *fs_type,
+		       int flags, const char *dev_name, void *data)
+{
+	struct super_block *sb;
+	struct ceph_fs_client *fsc;
+	struct dentry *res;
+	int err;
+	int (*compare_super)(struct super_block *, void *) = ceph_compare_super;
+	const char *path = NULL;
+	struct ceph_mount_options *fsopt = NULL;
+	struct ceph_options *opt = NULL;
+
+	dout("ceph_mount\n");
+
+#ifdef CONFIG_CEPH_FS_POSIX_ACL
+	flags |= MS_POSIXACL;
+#endif
+	err = parse_mount_options(&fsopt, &opt, flags, data, dev_name, &path);
+	if (err < 0) {
+		res = ERR_PTR(err);
+		goto out_final;
+	}
+
+	/* create client (which we may/may not use) */
+	fsc = create_fs_client(fsopt, opt);
+	if (IS_ERR(fsc)) {
+		res = ERR_CAST(fsc);
+		destroy_mount_options(fsopt);
+		ceph_destroy_options(opt);
+		goto out_final;
+	}
+
+	err = ceph_mdsc_init(fsc);
+	if (err < 0) {
+		res = ERR_PTR(err);
+		goto out;
+	}
+
+	if (ceph_test_opt(fsc->client, NOSHARE))
+		compare_super = NULL;
+	sb = sget(fs_type, compare_super, ceph_set_super, flags, fsc);
+	if (IS_ERR(sb)) {
+		res = ERR_CAST(sb);
+		goto out;
+	}
+
+	if (ceph_sb_to_client(sb) != fsc) {
+		ceph_mdsc_destroy(fsc);
+		destroy_fs_client(fsc);
+		fsc = ceph_sb_to_client(sb);
+		dout("get_sb got existing client %p\n", fsc);
+	} else {
+		dout("get_sb using new client %p\n", fsc);
+		err = ceph_register_bdi(sb, fsc);
+		if (err < 0) {
+			res = ERR_PTR(err);
+			goto out_splat;
+		}
+	}
+
+	res = ceph_real_mount(fsc, path);
+	if (IS_ERR(res))
+		goto out_splat;
+	dout("root %p inode %p ino %llx.%llx\n", res,
+	     d_inode(res), ceph_vinop(d_inode(res)));
+	return res;
+
+out_splat:
+	ceph_mdsc_close_sessions(fsc->mdsc);
+	deactivate_locked_super(sb);
+	goto out_final;
+
+out:
+	ceph_mdsc_destroy(fsc);
+	destroy_fs_client(fsc);
+out_final:
+	dout("ceph_mount fail %ld\n", PTR_ERR(res));
+	return res;
+}
+
+static void ceph_kill_sb(struct super_block *s)
+{
+	struct ceph_fs_client *fsc = ceph_sb_to_client(s);
+	dev_t dev = s->s_dev;
+
+	dout("kill_sb %p\n", s);
+
+	ceph_mdsc_pre_umount(fsc->mdsc);
+	generic_shutdown_super(s);
+	ceph_mdsc_destroy(fsc);
+
+	destroy_fs_client(fsc);
+	free_anon_bdev(dev);
+}
+
+static struct file_system_type ceph_fs_type = {
+	.owner		= THIS_MODULE,
+	.name		= "ceph",
+	.mount		= ceph_mount,
+	.kill_sb	= ceph_kill_sb,
+	.fs_flags	= FS_RENAME_DOES_D_MOVE,
+};
+MODULE_ALIAS_FS("ceph");
+
+static int __init init_ceph(void)
+{
+	int ret = init_caches();
+	if (ret)
+		goto out;
+
+	ceph_flock_init();
+	ceph_xattr_init();
+	ret = ceph_snap_init();
+	if (ret)
+		goto out_xattr;
+	ret = register_filesystem(&ceph_fs_type);
+	if (ret)
+		goto out_snap;
+
+	pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
+
+	return 0;
+
+out_snap:
+	ceph_snap_exit();
+out_xattr:
+	ceph_xattr_exit();
+	destroy_caches();
+out:
+	return ret;
+}
+
+static void __exit exit_ceph(void)
+{
+	dout("exit_ceph\n");
+	unregister_filesystem(&ceph_fs_type);
+	ceph_snap_exit();
+	ceph_xattr_exit();
+	destroy_caches();
+}
+
+module_init(init_ceph);
+module_exit(exit_ceph);
+
+MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
+MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
+MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
+MODULE_DESCRIPTION("Ceph filesystem for Linux");
+MODULE_LICENSE("GPL");