linux/fs/ceph/super.c

1060 lines
25 KiB
C

#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");