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kernel-ark/fs/ceph/super.c
Alex Elder 3bf53337af ceph: set up page array mempool with correct size 
In create_fs_client() a memory pool is set up be used for arrays of
pages that might be needed in ceph_writepages_start() if memory is
tight.  There are two problems with the way it's initialized:
    - The size provided is the number of pages we want in the
      array, but it should be the number of bytes required for
      that many page pointers.
    - The number of pages computed can end up being 0, while we
      will always need at least one page.

This patch fixes both of these problems.

This resolves the two simple problems defined in:
    http://tracker.ceph.com/issues/4603

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01 21:17:50 -07:00

1001 lines
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#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 <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);
/*
* ensure we release the bdi before put_anon_super releases
* the device name.
*/
if (s->s_bdi == &fsc->backing_dev_info) {
bdi_unregister(&fsc->backing_dev_info);
s->s_bdi = NULL;
}
return;
}
static int ceph_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct ceph_fs_client *fsc = ceph_inode_to_client(dentry->d_inode);
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,
};
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"},
{-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;
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);
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 != ':') {
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;
struct ceph_options *opt = fsc->client->options;
if (opt->flags & CEPH_OPT_FSID)
seq_printf(m, ",fsid=%pU", &opt->fsid);
if (opt->flags & CEPH_OPT_NOSHARE)
seq_puts(m, ",noshare");
if (opt->flags & CEPH_OPT_NOCRC)
seq_puts(m, ",nocrc");
if (opt->name)
seq_printf(m, ",name=%s", opt->name);
if (opt->key)
seq_puts(m, ",secret=<hidden>");
if (opt->mount_timeout != CEPH_MOUNT_TIMEOUT_DEFAULT)
seq_printf(m, ",mount_timeout=%d", opt->mount_timeout);
if (opt->osd_idle_ttl != CEPH_OSD_IDLE_TTL_DEFAULT)
seq_printf(m, ",osd_idle_ttl=%d", opt->osd_idle_ttl);
if (opt->osd_keepalive_timeout != CEPH_OSD_KEEPALIVE_DEFAULT)
seq_printf(m, ",osdkeepalivetimeout=%d",
opt->osd_keepalive_timeout);
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)
seq_puts(m, ",dcache");
else
seq_puts(m, ",nodcache");
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 unsigned supported_features =
CEPH_FEATURE_FLOCK |
CEPH_FEATURE_DIRLAYOUTHASH;
const unsigned 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;
/* caps */
fsc->min_caps = fsopt->max_readdir;
return 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);
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)
{
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;
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 -ENOMEM;
}
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_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,
.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);
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_alias(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_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 =
default_backing_dev_info.ra_pages;
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");
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,
res->d_inode, ceph_vinop(res->d_inode));
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);
dout("kill_sb %p\n", s);
ceph_mdsc_pre_umount(fsc->mdsc);
kill_anon_super(s); /* will call put_super after sb is r/o */
ceph_mdsc_destroy(fsc);
destroy_fs_client(fsc);
}
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");
#define _STRINGIFY(x) #x
#define STRINGIFY(x) _STRINGIFY(x)
static int __init init_ceph(void)
{
int ret = init_caches();
if (ret)
goto out;
ceph_xattr_init();
ret = register_filesystem(&ceph_fs_type);
if (ret)
goto out_icache;
pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
return 0;
out_icache:
ceph_xattr_exit();
destroy_caches();
out:
return ret;
}
static void __exit exit_ceph(void)
{
dout("exit_ceph\n");
unregister_filesystem(&ceph_fs_type);
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");
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