blob: 9049c2a3e972f499ea1371e8c4b8112ead98a6e3 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
#include <linux/ceph/ceph_debug.h>
#include <linux/fs.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/gfp.h>
#include <linux/sched.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/ratelimit.h>
#include "super.h"
#include "mds_client.h"
#include <linux/ceph/ceph_features.h>
#include <linux/ceph/messenger.h>
#include <linux/ceph/decode.h>
#include <linux/ceph/pagelist.h>
#include <linux/ceph/auth.h>
#include <linux/ceph/debugfs.h>
#define RECONNECT_MAX_SIZE (INT_MAX - PAGE_SIZE)
/*
* A cluster of MDS (metadata server) daemons is responsible for
* managing the file system namespace (the directory hierarchy and
* inodes) and for coordinating shared access to storage. Metadata is
* partitioning hierarchically across a number of servers, and that
* partition varies over time as the cluster adjusts the distribution
* in order to balance load.
*
* The MDS client is primarily responsible to managing synchronous
* metadata requests for operations like open, unlink, and so forth.
* If there is a MDS failure, we find out about it when we (possibly
* request and) receive a new MDS map, and can resubmit affected
* requests.
*
* For the most part, though, we take advantage of a lossless
* communications channel to the MDS, and do not need to worry about
* timing out or resubmitting requests.
*
* We maintain a stateful "session" with each MDS we interact with.
* Within each session, we sent periodic heartbeat messages to ensure
* any capabilities or leases we have been issues remain valid. If
* the session times out and goes stale, our leases and capabilities
* are no longer valid.
*/
struct ceph_reconnect_state {
struct ceph_mds_session *session;
int nr_caps, nr_realms;
struct ceph_pagelist *pagelist;
unsigned msg_version;
bool allow_multi;
};
static void __wake_requests(struct ceph_mds_client *mdsc,
struct list_head *head);
static void ceph_cap_release_work(struct work_struct *work);
static void ceph_cap_reclaim_work(struct work_struct *work);
static const struct ceph_connection_operations mds_con_ops;
/*
* mds reply parsing
*/
static int parse_reply_info_quota(void **p, void *end,
struct ceph_mds_reply_info_in *info)
{
u8 struct_v, struct_compat;
u32 struct_len;
ceph_decode_8_safe(p, end, struct_v, bad);
ceph_decode_8_safe(p, end, struct_compat, bad);
/* struct_v is expected to be >= 1. we only
* understand encoding with struct_compat == 1. */
if (!struct_v || struct_compat != 1)
goto bad;
ceph_decode_32_safe(p, end, struct_len, bad);
ceph_decode_need(p, end, struct_len, bad);
end = *p + struct_len;
ceph_decode_64_safe(p, end, info->max_bytes, bad);
ceph_decode_64_safe(p, end, info->max_files, bad);
*p = end;
return 0;
bad:
return -EIO;
}
/*
* parse individual inode info
*/
static int parse_reply_info_in(void **p, void *end,
struct ceph_mds_reply_info_in *info,
u64 features)
{
int err = 0;
u8 struct_v = 0;
if (features == (u64)-1) {
u32 struct_len;
u8 struct_compat;
ceph_decode_8_safe(p, end, struct_v, bad);
ceph_decode_8_safe(p, end, struct_compat, bad);
/* struct_v is expected to be >= 1. we only understand
* encoding with struct_compat == 1. */
if (!struct_v || struct_compat != 1)
goto bad;
ceph_decode_32_safe(p, end, struct_len, bad);
ceph_decode_need(p, end, struct_len, bad);
end = *p + struct_len;
}
ceph_decode_need(p, end, sizeof(struct ceph_mds_reply_inode), bad);
info->in = *p;
*p += sizeof(struct ceph_mds_reply_inode) +
sizeof(*info->in->fragtree.splits) *
le32_to_cpu(info->in->fragtree.nsplits);
ceph_decode_32_safe(p, end, info->symlink_len, bad);
ceph_decode_need(p, end, info->symlink_len, bad);
info->symlink = *p;
*p += info->symlink_len;
ceph_decode_copy_safe(p, end, &info->dir_layout,
sizeof(info->dir_layout), bad);
ceph_decode_32_safe(p, end, info->xattr_len, bad);
ceph_decode_need(p, end, info->xattr_len, bad);
info->xattr_data = *p;
*p += info->xattr_len;
if (features == (u64)-1) {
/* inline data */
ceph_decode_64_safe(p, end, info->inline_version, bad);
ceph_decode_32_safe(p, end, info->inline_len, bad);
ceph_decode_need(p, end, info->inline_len, bad);
info->inline_data = *p;
*p += info->inline_len;
/* quota */
err = parse_reply_info_quota(p, end, info);
if (err < 0)
goto out_bad;
/* pool namespace */
ceph_decode_32_safe(p, end, info->pool_ns_len, bad);
if (info->pool_ns_len > 0) {
ceph_decode_need(p, end, info->pool_ns_len, bad);
info->pool_ns_data = *p;
*p += info->pool_ns_len;
}
/* btime, change_attr */
{
struct ceph_timespec btime;
u64 change_attr;
ceph_decode_need(p, end, sizeof(btime), bad);
ceph_decode_copy(p, &btime, sizeof(btime));
ceph_decode_64_safe(p, end, change_attr, bad);
}
/* dir pin */
if (struct_v >= 2) {
ceph_decode_32_safe(p, end, info->dir_pin, bad);
} else {
info->dir_pin = -ENODATA;
}
*p = end;
} else {
if (features & CEPH_FEATURE_MDS_INLINE_DATA) {
ceph_decode_64_safe(p, end, info->inline_version, bad);
ceph_decode_32_safe(p, end, info->inline_len, bad);
ceph_decode_need(p, end, info->inline_len, bad);
info->inline_data = *p;
*p += info->inline_len;
} else
info->inline_version = CEPH_INLINE_NONE;
if (features & CEPH_FEATURE_MDS_QUOTA) {
err = parse_reply_info_quota(p, end, info);
if (err < 0)
goto out_bad;
} else {
info->max_bytes = 0;
info->max_files = 0;
}
info->pool_ns_len = 0;
info->pool_ns_data = NULL;
if (features & CEPH_FEATURE_FS_FILE_LAYOUT_V2) {
ceph_decode_32_safe(p, end, info->pool_ns_len, bad);
if (info->pool_ns_len > 0) {
ceph_decode_need(p, end, info->pool_ns_len, bad);
info->pool_ns_data = *p;
*p += info->pool_ns_len;
}
}
info->dir_pin = -ENODATA;
}
return 0;
bad:
err = -EIO;
out_bad:
return err;
}
static int parse_reply_info_dir(void **p, void *end,
struct ceph_mds_reply_dirfrag **dirfrag,
u64 features)
{
if (features == (u64)-1) {
u8 struct_v, struct_compat;
u32 struct_len;
ceph_decode_8_safe(p, end, struct_v, bad);
ceph_decode_8_safe(p, end, struct_compat, bad);
/* struct_v is expected to be >= 1. we only understand
* encoding whose struct_compat == 1. */
if (!struct_v || struct_compat != 1)
goto bad;
ceph_decode_32_safe(p, end, struct_len, bad);
ceph_decode_need(p, end, struct_len, bad);
end = *p + struct_len;
}
ceph_decode_need(p, end, sizeof(**dirfrag), bad);
*dirfrag = *p;
*p += sizeof(**dirfrag) + sizeof(u32) * le32_to_cpu((*dirfrag)->ndist);
if (unlikely(*p > end))
goto bad;
if (features == (u64)-1)
*p = end;
return 0;
bad:
return -EIO;
}
static int parse_reply_info_lease(void **p, void *end,
struct ceph_mds_reply_lease **lease,
u64 features)
{
if (features == (u64)-1) {
u8 struct_v, struct_compat;
u32 struct_len;
ceph_decode_8_safe(p, end, struct_v, bad);
ceph_decode_8_safe(p, end, struct_compat, bad);
/* struct_v is expected to be >= 1. we only understand
* encoding whose struct_compat == 1. */
if (!struct_v || struct_compat != 1)
goto bad;
ceph_decode_32_safe(p, end, struct_len, bad);
ceph_decode_need(p, end, struct_len, bad);
end = *p + struct_len;
}
ceph_decode_need(p, end, sizeof(**lease), bad);
*lease = *p;
*p += sizeof(**lease);
if (features == (u64)-1)
*p = end;
return 0;
bad:
return -EIO;
}
/*
* parse a normal reply, which may contain a (dir+)dentry and/or a
* target inode.
*/
static int parse_reply_info_trace(void **p, void *end,
struct ceph_mds_reply_info_parsed *info,
u64 features)
{
int err;
if (info->head->is_dentry) {
err = parse_reply_info_in(p, end, &info->diri, features);
if (err < 0)
goto out_bad;
err = parse_reply_info_dir(p, end, &info->dirfrag, features);
if (err < 0)
goto out_bad;
ceph_decode_32_safe(p, end, info->dname_len, bad);
ceph_decode_need(p, end, info->dname_len, bad);
info->dname = *p;
*p += info->dname_len;
err = parse_reply_info_lease(p, end, &info->dlease, features);
if (err < 0)
goto out_bad;
}
if (info->head->is_target) {
err = parse_reply_info_in(p, end, &info->targeti, features);
if (err < 0)
goto out_bad;
}
if (unlikely(*p != end))
goto bad;
return 0;
bad:
err = -EIO;
out_bad:
pr_err("problem parsing mds trace %d\n", err);
return err;
}
/*
* parse readdir results
*/
static int parse_reply_info_readdir(void **p, void *end,
struct ceph_mds_reply_info_parsed *info,
u64 features)
{
u32 num, i = 0;
int err;
err = parse_reply_info_dir(p, end, &info->dir_dir, features);
if (err < 0)
goto out_bad;
ceph_decode_need(p, end, sizeof(num) + 2, bad);
num = ceph_decode_32(p);
{
u16 flags = ceph_decode_16(p);
info->dir_end = !!(flags & CEPH_READDIR_FRAG_END);
info->dir_complete = !!(flags & CEPH_READDIR_FRAG_COMPLETE);
info->hash_order = !!(flags & CEPH_READDIR_HASH_ORDER);
info->offset_hash = !!(flags & CEPH_READDIR_OFFSET_HASH);
}
if (num == 0)
goto done;
BUG_ON(!info->dir_entries);
if ((unsigned long)(info->dir_entries + num) >
(unsigned long)info->dir_entries + info->dir_buf_size) {
pr_err("dir contents are larger than expected\n");
WARN_ON(1);
goto bad;
}
info->dir_nr = num;
while (num) {
struct ceph_mds_reply_dir_entry *rde = info->dir_entries + i;
/* dentry */
ceph_decode_32_safe(p, end, rde->name_len, bad);
ceph_decode_need(p, end, rde->name_len, bad);
rde->name = *p;
*p += rde->name_len;
dout("parsed dir dname '%.*s'\n", rde->name_len, rde->name);
/* dentry lease */
err = parse_reply_info_lease(p, end, &rde->lease, features);
if (err)
goto out_bad;
/* inode */
err = parse_reply_info_in(p, end, &rde->inode, features);
if (err < 0)
goto out_bad;
/* ceph_readdir_prepopulate() will update it */
rde->offset = 0;
i++;
num--;
}
done:
if (*p != end)
goto bad;
return 0;
bad:
err = -EIO;
out_bad:
pr_err("problem parsing dir contents %d\n", err);
return err;
}
/*
* parse fcntl F_GETLK results
*/
static int parse_reply_info_filelock(void **p, void *end,
struct ceph_mds_reply_info_parsed *info,
u64 features)
{
if (*p + sizeof(*info->filelock_reply) > end)
goto bad;
info->filelock_reply = *p;
*p += sizeof(*info->filelock_reply);
if (unlikely(*p != end))
goto bad;
return 0;
bad:
return -EIO;
}
/*
* parse create results
*/
static int parse_reply_info_create(void **p, void *end,
struct ceph_mds_reply_info_parsed *info,
u64 features)
{
if (features == (u64)-1 ||
(features & CEPH_FEATURE_REPLY_CREATE_INODE)) {
if (*p == end) {
info->has_create_ino = false;
} else {
info->has_create_ino = true;
info->ino = ceph_decode_64(p);
}
}
if (unlikely(*p != end))
goto bad;
return 0;
bad:
return -EIO;
}
/*
* parse extra results
*/
static int parse_reply_info_extra(void **p, void *end,
struct ceph_mds_reply_info_parsed *info,
u64 features)
{
u32 op = le32_to_cpu(info->head->op);
if (op == CEPH_MDS_OP_GETFILELOCK)
return parse_reply_info_filelock(p, end, info, features);
else if (op == CEPH_MDS_OP_READDIR || op == CEPH_MDS_OP_LSSNAP)
return parse_reply_info_readdir(p, end, info, features);
else if (op == CEPH_MDS_OP_CREATE)
return parse_reply_info_create(p, end, info, features);
else
return -EIO;
}
/*
* parse entire mds reply
*/
static int parse_reply_info(struct ceph_msg *msg,
struct ceph_mds_reply_info_parsed *info,
u64 features)
{
void *p, *end;
u32 len;
int err;
info->head = msg->front.iov_base;
p = msg->front.iov_base + sizeof(struct ceph_mds_reply_head);
end = p + msg->front.iov_len - sizeof(struct ceph_mds_reply_head);
/* trace */
ceph_decode_32_safe(&p, end, len, bad);
if (len > 0) {
ceph_decode_need(&p, end, len, bad);
err = parse_reply_info_trace(&p, p+len, info, features);
if (err < 0)
goto out_bad;
}
/* extra */
ceph_decode_32_safe(&p, end, len, bad);
if (len > 0) {
ceph_decode_need(&p, end, len, bad);
err = parse_reply_info_extra(&p, p+len, info, features);
if (err < 0)
goto out_bad;
}
/* snap blob */
ceph_decode_32_safe(&p, end, len, bad);
info->snapblob_len = len;
info->snapblob = p;
p += len;
if (p != end)
goto bad;
return 0;
bad:
err = -EIO;
out_bad:
pr_err("mds parse_reply err %d\n", err);
return err;
}
static void destroy_reply_info(struct ceph_mds_reply_info_parsed *info)
{
if (!info->dir_entries)
return;
free_pages((unsigned long)info->dir_entries, get_order(info->dir_buf_size));
}
/*
* sessions
*/
const char *ceph_session_state_name(int s)
{
switch (s) {
case CEPH_MDS_SESSION_NEW: return "new";
case CEPH_MDS_SESSION_OPENING: return "opening";
case CEPH_MDS_SESSION_OPEN: return "open";
case CEPH_MDS_SESSION_HUNG: return "hung";
case CEPH_MDS_SESSION_CLOSING: return "closing";
case CEPH_MDS_SESSION_RESTARTING: return "restarting";
case CEPH_MDS_SESSION_RECONNECTING: return "reconnecting";
case CEPH_MDS_SESSION_REJECTED: return "rejected";
default: return "???";
}
}
static struct ceph_mds_session *get_session(struct ceph_mds_session *s)
{
if (refcount_inc_not_zero(&s->s_ref)) {
dout("mdsc get_session %p %d -> %d\n", s,
refcount_read(&s->s_ref)-1, refcount_read(&s->s_ref));
return s;
} else {
dout("mdsc get_session %p 0 -- FAIL\n", s);
return NULL;
}
}
void ceph_put_mds_session(struct ceph_mds_session *s)
{
dout("mdsc put_session %p %d -> %d\n", s,
refcount_read(&s->s_ref), refcount_read(&s->s_ref)-1);
if (refcount_dec_and_test(&s->s_ref)) {
if (s->s_auth.authorizer)
ceph_auth_destroy_authorizer(s->s_auth.authorizer);
kfree(s);
}
}
/*
* called under mdsc->mutex
*/
struct ceph_mds_session *__ceph_lookup_mds_session(struct ceph_mds_client *mdsc,
int mds)
{
struct ceph_mds_session *session;
if (mds >= mdsc->max_sessions || !mdsc->sessions[mds])
return NULL;
session = mdsc->sessions[mds];
dout("lookup_mds_session %p %d\n", session,
refcount_read(&session->s_ref));
get_session(session);
return session;
}
static bool __have_session(struct ceph_mds_client *mdsc, int mds)
{
if (mds >= mdsc->max_sessions || !mdsc->sessions[mds])
return false;
else
return true;
}
static int __verify_registered_session(struct ceph_mds_client *mdsc,
struct ceph_mds_session *s)
{
if (s->s_mds >= mdsc->max_sessions ||
mdsc->sessions[s->s_mds] != s)
return -ENOENT;
return 0;
}
/*
* create+register a new session for given mds.
* called under mdsc->mutex.
*/
static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc,
int mds)
{
struct ceph_mds_session *s;
if (mds >= mdsc->mdsmap->m_num_mds)
return ERR_PTR(-EINVAL);
s = kzalloc(sizeof(*s), GFP_NOFS);
if (!s)
return ERR_PTR(-ENOMEM);
if (mds >= mdsc->max_sessions) {
int newmax = 1 << get_count_order(mds + 1);
struct ceph_mds_session **sa;
dout("%s: realloc to %d\n", __func__, newmax);
sa = kcalloc(newmax, sizeof(void *), GFP_NOFS);
if (!sa)
goto fail_realloc;
if (mdsc->sessions) {
memcpy(sa, mdsc->sessions,
mdsc->max_sessions * sizeof(void *));
kfree(mdsc->sessions);
}
mdsc->sessions = sa;
mdsc->max_sessions = newmax;
}
dout("%s: mds%d\n", __func__, mds);
s->s_mdsc = mdsc;
s->s_mds = mds;
s->s_state = CEPH_MDS_SESSION_NEW;
s->s_ttl = 0;
s->s_seq = 0;
mutex_init(&s->s_mutex);
ceph_con_init(&s->s_con, s, &mds_con_ops, &mdsc->fsc->client->msgr);
spin_lock_init(&s->s_gen_ttl_lock);
s->s_cap_gen = 1;
s->s_cap_ttl = jiffies - 1;
spin_lock_init(&s->s_cap_lock);
s->s_renew_requested = 0;
s->s_renew_seq = 0;
INIT_LIST_HEAD(&s->s_caps);
s->s_nr_caps = 0;
s->s_trim_caps = 0;
refcount_set(&s->s_ref, 1);
INIT_LIST_HEAD(&s->s_waiting);
INIT_LIST_HEAD(&s->s_unsafe);
s->s_num_cap_releases = 0;
s->s_cap_reconnect = 0;
s->s_cap_iterator = NULL;
INIT_LIST_HEAD(&s->s_cap_releases);
INIT_WORK(&s->s_cap_release_work, ceph_cap_release_work);
INIT_LIST_HEAD(&s->s_cap_flushing);
mdsc->sessions[mds] = s;
atomic_inc(&mdsc->num_sessions);
refcount_inc(&s->s_ref); /* one ref to sessions[], one to caller */
ceph_con_open(&s->s_con, CEPH_ENTITY_TYPE_MDS, mds,
ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
return s;
fail_realloc:
kfree(s);
return ERR_PTR(-ENOMEM);
}
/*
* called under mdsc->mutex
*/
static void __unregister_session(struct ceph_mds_client *mdsc,
struct ceph_mds_session *s)
{
dout("__unregister_session mds%d %p\n", s->s_mds, s);
BUG_ON(mdsc->sessions[s->s_mds] != s);
mdsc->sessions[s->s_mds] = NULL;
s->s_state = 0;
ceph_con_close(&s->s_con);
ceph_put_mds_session(s);
atomic_dec(&mdsc->num_sessions);
}
/*
* drop session refs in request.
*
* should be last request ref, or hold mdsc->mutex
*/
static void put_request_session(struct ceph_mds_request *req)
{
if (req->r_session) {
ceph_put_mds_session(req->r_session);
req->r_session = NULL;
}
}
void ceph_mdsc_release_request(struct kref *kref)
{
struct ceph_mds_request *req = container_of(kref,
struct ceph_mds_request,
r_kref);
destroy_reply_info(&req->r_reply_info);
if (req->r_request)
ceph_msg_put(req->r_request);
if (req->r_reply)
ceph_msg_put(req->r_reply);
if (req->r_inode) {
ceph_put_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
iput(req->r_inode);
}
if (req->r_parent)
ceph_put_cap_refs(ceph_inode(req->r_parent), CEPH_CAP_PIN);
iput(req->r_target_inode);
if (req->r_dentry)
dput(req->r_dentry);
if (req->r_old_dentry)
dput(req->r_old_dentry);
if (req->r_old_dentry_dir) {
/*
* track (and drop pins for) r_old_dentry_dir
* separately, since r_old_dentry's d_parent may have
* changed between the dir mutex being dropped and
* this request being freed.
*/
ceph_put_cap_refs(ceph_inode(req->r_old_dentry_dir),
CEPH_CAP_PIN);
iput(req->r_old_dentry_dir);
}
kfree(req->r_path1);
kfree(req->r_path2);
if (req->r_pagelist)
ceph_pagelist_release(req->r_pagelist);
put_request_session(req);
ceph_unreserve_caps(req->r_mdsc, &req->r_caps_reservation);
kfree(req);
}
DEFINE_RB_FUNCS(request, struct ceph_mds_request, r_tid, r_node)
/*
* lookup session, bump ref if found.
*
* called under mdsc->mutex.
*/
static struct ceph_mds_request *
lookup_get_request(struct ceph_mds_client *mdsc, u64 tid)
{
struct ceph_mds_request *req;
req = lookup_request(&mdsc->request_tree, tid);
if (req)
ceph_mdsc_get_request(req);
return req;
}
/*
* Register an in-flight request, and assign a tid. Link to directory
* are modifying (if any).
*
* Called under mdsc->mutex.
*/
static void __register_request(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req,
struct inode *dir)
{
int ret = 0;
req->r_tid = ++mdsc->last_tid;
if (req->r_num_caps) {
ret = ceph_reserve_caps(mdsc, &req->r_caps_reservation,
req->r_num_caps);
if (ret < 0) {
pr_err("__register_request %p "
"failed to reserve caps: %d\n", req, ret);
/* set req->r_err to fail early from __do_request */
req->r_err = ret;
return;
}
}
dout("__register_request %p tid %lld\n", req, req->r_tid);
ceph_mdsc_get_request(req);
insert_request(&mdsc->request_tree, req);
req->r_uid = current_fsuid();
req->r_gid = current_fsgid();
if (mdsc->oldest_tid == 0 && req->r_op != CEPH_MDS_OP_SETFILELOCK)
mdsc->oldest_tid = req->r_tid;
if (dir) {
ihold(dir);
req->r_unsafe_dir = dir;
}
}
static void __unregister_request(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req)
{
dout("__unregister_request %p tid %lld\n", req, req->r_tid);
/* Never leave an unregistered request on an unsafe list! */
list_del_init(&req->r_unsafe_item);
if (req->r_tid == mdsc->oldest_tid) {
struct rb_node *p = rb_next(&req->r_node);
mdsc->oldest_tid = 0;
while (p) {
struct ceph_mds_request *next_req =
rb_entry(p, struct ceph_mds_request, r_node);
if (next_req->r_op != CEPH_MDS_OP_SETFILELOCK) {
mdsc->oldest_tid = next_req->r_tid;
break;
}
p = rb_next(p);
}
}
erase_request(&mdsc->request_tree, req);
if (req->r_unsafe_dir &&
test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) {
struct ceph_inode_info *ci = ceph_inode(req->r_unsafe_dir);
spin_lock(&ci->i_unsafe_lock);
list_del_init(&req->r_unsafe_dir_item);
spin_unlock(&ci->i_unsafe_lock);
}
if (req->r_target_inode &&
test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) {
struct ceph_inode_info *ci = ceph_inode(req->r_target_inode);
spin_lock(&ci->i_unsafe_lock);
list_del_init(&req->r_unsafe_target_item);
spin_unlock(&ci->i_unsafe_lock);
}
if (req->r_unsafe_dir) {
iput(req->r_unsafe_dir);
req->r_unsafe_dir = NULL;
}
complete_all(&req->r_safe_completion);
ceph_mdsc_put_request(req);
}
/*
* Walk back up the dentry tree until we hit a dentry representing a
* non-snapshot inode. We do this using the rcu_read_lock (which must be held
* when calling this) to ensure that the objects won't disappear while we're
* working with them. Once we hit a candidate dentry, we attempt to take a
* reference to it, and return that as the result.
*/
static struct inode *get_nonsnap_parent(struct dentry *dentry)
{
struct inode *inode = NULL;
while (dentry && !IS_ROOT(dentry)) {
inode = d_inode_rcu(dentry);
if (!inode || ceph_snap(inode) == CEPH_NOSNAP)
break;
dentry = dentry->d_parent;
}
if (inode)
inode = igrab(inode);
return inode;
}
/*
* Choose mds to send request to next. If there is a hint set in the
* request (e.g., due to a prior forward hint from the mds), use that.
* Otherwise, consult frag tree and/or caps to identify the
* appropriate mds. If all else fails, choose randomly.
*
* Called under mdsc->mutex.
*/
static int __choose_mds(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req)
{
struct inode *inode;
struct ceph_inode_info *ci;
struct ceph_cap *cap;
int mode = req->r_direct_mode;
int mds = -1;
u32 hash = req->r_direct_hash;
bool is_hash = test_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags);
/*
* is there a specific mds we should try? ignore hint if we have
* no session and the mds is not up (active or recovering).
*/
if (req->r_resend_mds >= 0 &&
(__have_session(mdsc, req->r_resend_mds) ||
ceph_mdsmap_get_state(mdsc->mdsmap, req->r_resend_mds) > 0)) {
dout("choose_mds using resend_mds mds%d\n",
req->r_resend_mds);
return req->r_resend_mds;
}
if (mode == USE_RANDOM_MDS)
goto random;
inode = NULL;
if (req->r_inode) {
if (ceph_snap(req->r_inode) != CEPH_SNAPDIR) {
inode = req->r_inode;
ihold(inode);
} else {
/* req->r_dentry is non-null for LSSNAP request */
rcu_read_lock();
inode = get_nonsnap_parent(req->r_dentry);
rcu_read_unlock();
dout("__choose_mds using snapdir's parent %p\n", inode);
}
} else if (req->r_dentry) {
/* ignore race with rename; old or new d_parent is okay */
struct dentry *parent;
struct inode *dir;
rcu_read_lock();
parent = req->r_dentry->d_parent;
dir = req->r_parent ? : d_inode_rcu(parent);
if (!dir || dir->i_sb != mdsc->fsc->sb) {
/* not this fs or parent went negative */
inode = d_inode(req->r_dentry);
if (inode)
ihold(inode);
} else if (ceph_snap(dir) != CEPH_NOSNAP) {
/* direct snapped/virtual snapdir requests
* based on parent dir inode */
inode = get_nonsnap_parent(parent);
dout("__choose_mds using nonsnap parent %p\n", inode);
} else {
/* dentry target */
inode = d_inode(req->r_dentry);
if (!inode || mode == USE_AUTH_MDS) {
/* dir + name */
inode = igrab(dir);
hash = ceph_dentry_hash(dir, req->r_dentry);
is_hash = true;
} else {
ihold(inode);
}
}
rcu_read_unlock();
}
dout("__choose_mds %p is_hash=%d (%d) mode %d\n", inode, (int)is_hash,
(int)hash, mode);
if (!inode)
goto random;
ci = ceph_inode(inode);
if (is_hash && S_ISDIR(inode->i_mode)) {
struct ceph_inode_frag frag;
int found;
ceph_choose_frag(ci, hash, &frag, &found);
if (found) {
if (mode == USE_ANY_MDS && frag.ndist > 0) {
u8 r;
/* choose a random replica */
get_random_bytes(&r, 1);
r %= frag.ndist;
mds = frag.dist[r];
dout("choose_mds %p %llx.%llx "
"frag %u mds%d (%d/%d)\n",
inode, ceph_vinop(inode),
frag.frag, mds,
(int)r, frag.ndist);
if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >=
CEPH_MDS_STATE_ACTIVE)
goto out;
}
/* since this file/dir wasn't known to be
* replicated, then we want to look for the
* authoritative mds. */
mode = USE_AUTH_MDS;
if (frag.mds >= 0) {
/* choose auth mds */
mds = frag.mds;
dout("choose_mds %p %llx.%llx "
"frag %u mds%d (auth)\n",
inode, ceph_vinop(inode), frag.frag, mds);
if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >=
CEPH_MDS_STATE_ACTIVE)
goto out;
}
}
}
spin_lock(&ci->i_ceph_lock);
cap = NULL;
if (mode == USE_AUTH_MDS)
cap = ci->i_auth_cap;
if (!cap && !RB_EMPTY_ROOT(&ci->i_caps))
cap = rb_entry(rb_first(&ci->i_caps), struct ceph_cap, ci_node);
if (!cap) {
spin_unlock(&ci->i_ceph_lock);
iput(inode);
goto random;
}
mds = cap->session->s_mds;
dout("choose_mds %p %llx.%llx mds%d (%scap %p)\n",
inode, ceph_vinop(inode), mds,
cap == ci->i_auth_cap ? "auth " : "", cap);
spin_unlock(&ci->i_ceph_lock);
out:
iput(inode);
return mds;
random:
mds = ceph_mdsmap_get_random_mds(mdsc->mdsmap);
dout("choose_mds chose random mds%d\n", mds);
return mds;
}
/*
* session messages
*/
static struct ceph_msg *create_session_msg(u32 op, u64 seq)
{
struct ceph_msg *msg;
struct ceph_mds_session_head *h;
msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h), GFP_NOFS,
false);
if (!msg) {
pr_err("create_session_msg ENOMEM creating msg\n");
return NULL;
}
h = msg->front.iov_base;
h->op = cpu_to_le32(op);
h->seq = cpu_to_le64(seq);
return msg;
}
static void encode_supported_features(void **p, void *end)
{
static const unsigned char bits[] = CEPHFS_FEATURES_CLIENT_SUPPORTED;
static const size_t count = ARRAY_SIZE(bits);
if (count > 0) {
size_t i;
size_t size = ((size_t)bits[count - 1] + 64) / 64 * 8;
BUG_ON(*p + 4 + size > end);
ceph_encode_32(p, size);
memset(*p, 0, size);
for (i = 0; i < count; i++)
((unsigned char*)(*p))[i / 8] |= 1 << (bits[i] % 8);
*p += size;
} else {
BUG_ON(*p + 4 > end);
ceph_encode_32(p, 0);
}
}
/*
* session message, specialization for CEPH_SESSION_REQUEST_OPEN
* to include additional client metadata fields.
*/
static struct ceph_msg *create_session_open_msg(struct ceph_mds_client *mdsc, u64 seq)
{
struct ceph_msg *msg;
struct ceph_mds_session_head *h;
int i = -1;
int extra_bytes = 0;
int metadata_key_count = 0;
struct ceph_options *opt = mdsc->fsc->client->options;
struct ceph_mount_options *fsopt = mdsc->fsc->mount_options;
void *p, *end;
const char* metadata[][2] = {
{"hostname", mdsc->nodename},
{"kernel_version", init_utsname()->release},
{"entity_id", opt->name ? : ""},
{"root", fsopt->server_path ? : "/"},
{NULL, NULL}
};
/* Calculate serialized length of metadata */
extra_bytes = 4; /* map length */
for (i = 0; metadata[i][0]; ++i) {
extra_bytes += 8 + strlen(metadata[i][0]) +
strlen(metadata[i][1]);
metadata_key_count++;
}
/* supported feature */
extra_bytes += 4 + 8;
/* Allocate the message */
msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h) + extra_bytes,
GFP_NOFS, false);
if (!msg) {
pr_err("create_session_msg ENOMEM creating msg\n");
return NULL;
}
p = msg->front.iov_base;
end = p + msg->front.iov_len;
h = p;
h->op = cpu_to_le32(CEPH_SESSION_REQUEST_OPEN);
h->seq = cpu_to_le64(seq);
/*
* Serialize client metadata into waiting buffer space, using
* the format that userspace expects for map<string, string>
*
* ClientSession messages with metadata are v2
*/
msg->hdr.version = cpu_to_le16(3);
msg->hdr.compat_version = cpu_to_le16(1);
/* The write pointer, following the session_head structure */
p += sizeof(*h);
/* Number of entries in the map */
ceph_encode_32(&p, metadata_key_count);
/* Two length-prefixed strings for each entry in the map */
for (i = 0; metadata[i][0]; ++i) {
size_t const key_len = strlen(metadata[i][0]);
size_t const val_len = strlen(metadata[i][1]);
ceph_encode_32(&p, key_len);
memcpy(p, metadata[i][0], key_len);
p += key_len;
ceph_encode_32(&p, val_len);
memcpy(p, metadata[i][1], val_len);
p += val_len;
}
encode_supported_features(&p, end);
msg->front.iov_len = p - msg->front.iov_base;
msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
return msg;
}
/*
* send session open request.
*
* called under mdsc->mutex
*/
static int __open_session(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session)
{
struct ceph_msg *msg;
int mstate;
int mds = session->s_mds;
/* wait for mds to go active? */
mstate = ceph_mdsmap_get_state(mdsc->mdsmap, mds);
dout("open_session to mds%d (%s)\n", mds,
ceph_mds_state_name(mstate));
session->s_state = CEPH_MDS_SESSION_OPENING;
session->s_renew_requested = jiffies;
/* send connect message */
msg = create_session_open_msg(mdsc, session->s_seq);
if (!msg)
return -ENOMEM;
ceph_con_send(&session->s_con, msg);
return 0;
}
/*
* open sessions for any export targets for the given mds
*
* called under mdsc->mutex
*/
static struct ceph_mds_session *
__open_export_target_session(struct ceph_mds_client *mdsc, int target)
{
struct ceph_mds_session *session;
session = __ceph_lookup_mds_session(mdsc, target);
if (!session) {
session = register_session(mdsc, target);
if (IS_ERR(session))
return session;
}
if (session->s_state == CEPH_MDS_SESSION_NEW ||
session->s_state == CEPH_MDS_SESSION_CLOSING)
__open_session(mdsc, session);
return session;
}
struct ceph_mds_session *
ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target)
{
struct ceph_mds_session *session;
dout("open_export_target_session to mds%d\n", target);
mutex_lock(&mdsc->mutex);
session = __open_export_target_session(mdsc, target);
mutex_unlock(&mdsc->mutex);
return session;
}
static void __open_export_target_sessions(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session)
{
struct ceph_mds_info *mi;
struct ceph_mds_session *ts;
int i, mds = session->s_mds;
if (mds >= mdsc->mdsmap->m_num_mds)
return;
mi = &mdsc->mdsmap->m_info[mds];
dout("open_export_target_sessions for mds%d (%d targets)\n",
session->s_mds, mi->num_export_targets);
for (i = 0; i < mi->num_export_targets; i++) {
ts = __open_export_target_session(mdsc, mi->export_targets[i]);
if (!IS_ERR(ts))
ceph_put_mds_session(ts);
}
}
void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session)
{
mutex_lock(&mdsc->mutex);
__open_export_target_sessions(mdsc, session);
mutex_unlock(&mdsc->mutex);
}
/*
* session caps
*/
static void detach_cap_releases(struct ceph_mds_session *session,
struct list_head *target)
{
lockdep_assert_held(&session->s_cap_lock);
list_splice_init(&session->s_cap_releases, target);
session->s_num_cap_releases = 0;
dout("dispose_cap_releases mds%d\n", session->s_mds);
}
static void dispose_cap_releases(struct ceph_mds_client *mdsc,
struct list_head *dispose)
{
while (!list_empty(dispose)) {
struct ceph_cap *cap;
/* zero out the in-progress message */
cap = list_first_entry(dispose, struct ceph_cap, session_caps);
list_del(&cap->session_caps);
ceph_put_cap(mdsc, cap);
}
}
static void cleanup_session_requests(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session)
{
struct ceph_mds_request *req;
struct rb_node *p;
dout("cleanup_session_requests mds%d\n", session->s_mds);
mutex_lock(&mdsc->mutex);
while (!list_empty(&session->s_unsafe)) {
req = list_first_entry(&session->s_unsafe,
struct ceph_mds_request, r_unsafe_item);
pr_warn_ratelimited(" dropping unsafe request %llu\n",
req->r_tid);
__unregister_request(mdsc, req);
}
/* zero r_attempts, so kick_requests() will re-send requests */
p = rb_first(&mdsc->request_tree);
while (p) {
req = rb_entry(p, struct ceph_mds_request, r_node);
p = rb_next(p);
if (req->r_session &&
req->r_session->s_mds == session->s_mds)
req->r_attempts = 0;
}
mutex_unlock(&mdsc->mutex);
}
/*
* Helper to safely iterate over all caps associated with a session, with
* special care taken to handle a racing __ceph_remove_cap().
*
* Caller must hold session s_mutex.
*/
static int iterate_session_caps(struct ceph_mds_session *session,
int (*cb)(struct inode *, struct ceph_cap *,
void *), void *arg)
{
struct list_head *p;
struct ceph_cap *cap;
struct inode *inode, *last_inode = NULL;
struct ceph_cap *old_cap = NULL;
int ret;
dout("iterate_session_caps %p mds%d\n", session, session->s_mds);
spin_lock(&session->s_cap_lock);
p = session->s_caps.next;
while (p != &session->s_caps) {
cap = list_entry(p, struct ceph_cap, session_caps);
inode = igrab(&cap->ci->vfs_inode);
if (!inode) {
p = p->next;
continue;
}
session->s_cap_iterator = cap;
spin_unlock(&session->s_cap_lock);
if (last_inode) {
iput(last_inode);
last_inode = NULL;
}
if (old_cap) {
ceph_put_cap(session->s_mdsc, old_cap);
old_cap = NULL;
}
ret = cb(inode, cap, arg);
last_inode = inode;
spin_lock(&session->s_cap_lock);
p = p->next;
if (!cap->ci) {
dout("iterate_session_caps finishing cap %p removal\n",
cap);
BUG_ON(cap->session != session);
cap->session = NULL;
list_del_init(&cap->session_caps);
session->s_nr_caps--;
if (cap->queue_release)
__ceph_queue_cap_release(session, cap);
else
old_cap = cap; /* put_cap it w/o locks held */
}
if (ret < 0)
goto out;
}
ret = 0;
out:
session->s_cap_iterator = NULL;
spin_unlock(&session->s_cap_lock);
iput(last_inode);
if (old_cap)
ceph_put_cap(session->s_mdsc, old_cap);
return ret;
}
static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
void *arg)
{
struct ceph_fs_client *fsc = (struct ceph_fs_client *)arg;
struct ceph_inode_info *ci = ceph_inode(inode);
LIST_HEAD(to_remove);
bool drop = false;
bool invalidate = false;
dout("removing cap %p, ci is %p, inode is %p\n",
cap, ci, &ci->vfs_inode);
spin_lock(&ci->i_ceph_lock);
if (cap->mds_wanted | cap->issued)
ci->i_ceph_flags |= CEPH_I_CAP_DROPPED;
__ceph_remove_cap(cap, false);
if (!ci->i_auth_cap) {
struct ceph_cap_flush *cf;
struct ceph_mds_client *mdsc = fsc->mdsc;
if (ci->i_wrbuffer_ref > 0 &&
READ_ONCE(fsc->mount_state) == CEPH_MOUNT_SHUTDOWN)
invalidate = true;
while (!list_empty(&ci->i_cap_flush_list)) {
cf = list_first_entry(&ci->i_cap_flush_list,
struct ceph_cap_flush, i_list);
list_move(&cf->i_list, &to_remove);
}
spin_lock(&mdsc->cap_dirty_lock);
list_for_each_entry(cf, &to_remove, i_list)
list_del(&cf->g_list);
if (!list_empty(&ci->i_dirty_item)) {
pr_warn_ratelimited(
" dropping dirty %s state for %p %lld\n",
ceph_cap_string(ci->i_dirty_caps),
inode, ceph_ino(inode));
ci->i_dirty_caps = 0;
list_del_init(&ci->i_dirty_item);
drop = true;
}
if (!list_empty(&ci->i_flushing_item)) {
pr_warn_ratelimited(
" dropping dirty+flushing %s state for %p %lld\n",
ceph_cap_string(ci->i_flushing_caps),
inode, ceph_ino(inode));
ci->i_flushing_caps = 0;
list_del_init(&ci->i_flushing_item);
mdsc->num_cap_flushing--;
drop = true;
}
spin_unlock(&mdsc->cap_dirty_lock);
if (atomic_read(&ci->i_filelock_ref) > 0) {
/* make further file lock syscall return -EIO */
ci->i_ceph_flags |= CEPH_I_ERROR_FILELOCK;
pr_warn_ratelimited(" dropping file locks for %p %lld\n",
inode, ceph_ino(inode));
}
if (!ci->i_dirty_caps && ci->i_prealloc_cap_flush) {
list_add(&ci->i_prealloc_cap_flush->i_list, &to_remove);
ci->i_prealloc_cap_flush = NULL;
}
if (drop &&
ci->i_wrbuffer_ref_head == 0 &&
ci->i_wr_ref == 0 &&
ci->i_dirty_caps == 0 &&
ci->i_flushing_caps == 0) {
ceph_put_snap_context(ci->i_head_snapc);
ci->i_head_snapc = NULL;
}
}
spin_unlock(&ci->i_ceph_lock);
while (!list_empty(&to_remove)) {
struct ceph_cap_flush *cf;
cf = list_first_entry(&to_remove,
struct ceph_cap_flush, i_list);
list_del(&cf->i_list);
ceph_free_cap_flush(cf);
}
wake_up_all(&ci->i_cap_wq);
if (invalidate)
ceph_queue_invalidate(inode);
if (drop)
iput(inode);
return 0;
}
/*
* caller must hold session s_mutex
*/
static void remove_session_caps(struct ceph_mds_session *session)
{
struct ceph_fs_client *fsc = session->s_mdsc->fsc;
struct super_block *sb = fsc->sb;
LIST_HEAD(dispose);
dout("remove_session_caps on %p\n", session);
iterate_session_caps(session, remove_session_caps_cb, fsc);
wake_up_all(&fsc->mdsc->cap_flushing_wq);
spin_lock(&session->s_cap_lock);
if (session->s_nr_caps > 0) {
struct inode *inode;
struct ceph_cap *cap, *prev = NULL;
struct ceph_vino vino;
/*
* iterate_session_caps() skips inodes that are being
* deleted, we need to wait until deletions are complete.
* __wait_on_freeing_inode() is designed for the job,
* but it is not exported, so use lookup inode function
* to access it.
*/
while (!list_empty(&session->s_caps)) {
cap = list_entry(session->s_caps.next,
struct ceph_cap, session_caps);
if (cap == prev)
break;
prev = cap;
vino = cap->ci->i_vino;
spin_unlock(&session->s_cap_lock);
inode = ceph_find_inode(sb, vino);
iput(inode);
spin_lock(&session->s_cap_lock);
}
}
// drop cap expires and unlock s_cap_lock
detach_cap_releases(session, &dispose);
BUG_ON(session->s_nr_caps > 0);
BUG_ON(!list_empty(&session->s_cap_flushing));
spin_unlock(&session->s_cap_lock);
dispose_cap_releases(session->s_mdsc, &dispose);
}
enum {
RECONNECT,
RENEWCAPS,
FORCE_RO,
};
/*
* wake up any threads waiting on this session's caps. if the cap is
* old (didn't get renewed on the client reconnect), remove it now.
*
* caller must hold s_mutex.
*/
static int wake_up_session_cb(struct inode *inode, struct ceph_cap *cap,
void *arg)
{
struct ceph_inode_info *ci = ceph_inode(inode);
unsigned long ev = (unsigned long)arg;
if (ev == RECONNECT) {
spin_lock(&ci->i_ceph_lock);
ci->i_wanted_max_size = 0;
ci->i_requested_max_size = 0;
spin_unlock(&ci->i_ceph_lock);
} else if (ev == RENEWCAPS) {
if (cap->cap_gen < cap->session->s_cap_gen) {
/* mds did not re-issue stale cap */
spin_lock(&ci->i_ceph_lock);
cap->issued = cap->implemented = CEPH_CAP_PIN;
/* make sure mds knows what we want */
if (__ceph_caps_file_wanted(ci) & ~cap->mds_wanted)
ci->i_ceph_flags |= CEPH_I_CAP_DROPPED;
spin_unlock(&ci->i_ceph_lock);
}
} else if (ev == FORCE_RO) {
}
wake_up_all(&ci->i_cap_wq);
return 0;
}
static void wake_up_session_caps(struct ceph_mds_session *session, int ev)
{
dout("wake_up_session_caps %p mds%d\n", session, session->s_mds);
iterate_session_caps(session, wake_up_session_cb,
(void *)(unsigned long)ev);
}
/*
* Send periodic message to MDS renewing all currently held caps. The
* ack will reset the expiration for all caps from this session.
*
* caller holds s_mutex
*/
static int send_renew_caps(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session)
{
struct ceph_msg *msg;
int state;
if (time_after_eq(jiffies, session->s_cap_ttl) &&
time_after_eq(session->s_cap_ttl, session->s_renew_requested))
pr_info("mds%d caps stale\n", session->s_mds);
session->s_renew_requested = jiffies;
/* do not try to renew caps until a recovering mds has reconnected
* with its clients. */
state = ceph_mdsmap_get_state(mdsc->mdsmap, session->s_mds);
if (state < CEPH_MDS_STATE_RECONNECT) {
dout("send_renew_caps ignoring mds%d (%s)\n",
session->s_mds, ceph_mds_state_name(state));
return 0;
}
dout("send_renew_caps to mds%d (%s)\n", session->s_mds,
ceph_mds_state_name(state));
msg = create_session_msg(CEPH_SESSION_REQUEST_RENEWCAPS,
++session->s_renew_seq);
if (!msg)
return -ENOMEM;
ceph_con_send(&session->s_con, msg);
return 0;
}
static int send_flushmsg_ack(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session, u64 seq)
{
struct ceph_msg *msg;
dout("send_flushmsg_ack to mds%d (%s)s seq %lld\n",
session->s_mds, ceph_session_state_name(session->s_state), seq);
msg = create_session_msg(CEPH_SESSION_FLUSHMSG_ACK, seq);
if (!msg)
return -ENOMEM;
ceph_con_send(&session->s_con, msg);
return 0;
}
/*
* Note new cap ttl, and any transition from stale -> not stale (fresh?).
*
* Called under session->s_mutex
*/
static void renewed_caps(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session, int is_renew)
{
int was_stale;
int wake = 0;
spin_lock(&session->s_cap_lock);
was_stale = is_renew && time_after_eq(jiffies, session->s_cap_ttl);
session->s_cap_ttl = session->s_renew_requested +
mdsc->mdsmap->m_session_timeout*HZ;
if (was_stale) {
if (time_before(jiffies, session->s_cap_ttl)) {
pr_info("mds%d caps renewed\n", session->s_mds);
wake = 1;
} else {
pr_info("mds%d caps still stale\n", session->s_mds);
}
}
dout("renewed_caps mds%d ttl now %lu, was %s, now %s\n",
session->s_mds, session->s_cap_ttl, was_stale ? "stale" : "fresh",
time_before(jiffies, session->s_cap_ttl) ? "stale" : "fresh");
spin_unlock(&session->s_cap_lock);
if (wake)
wake_up_session_caps(session, RENEWCAPS);
}
/*
* send a session close request
*/
static int request_close_session(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session)
{
struct ceph_msg *msg;
dout("request_close_session mds%d state %s seq %lld\n",
session->s_mds, ceph_session_state_name(session->s_state),
session->s_seq);
msg = create_session_msg(CEPH_SESSION_REQUEST_CLOSE, session->s_seq);
if (!msg)
return -ENOMEM;
ceph_con_send(&session->s_con, msg);
return 1;
}
/*
* Called with s_mutex held.
*/
static int __close_session(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session)
{
if (session->s_state >= CEPH_MDS_SESSION_CLOSING)
return 0;
session->s_state = CEPH_MDS_SESSION_CLOSING;
return request_close_session(mdsc, session);
}
static bool drop_negative_children(struct dentry *dentry)
{
struct dentry *child;
bool all_negative = true;
if (!d_is_dir(dentry))
goto out;
spin_lock(&dentry->d_lock);
list_for_each_entry(child, &dentry->d_subdirs, d_child) {
if (d_really_is_positive(child)) {
all_negative = false;
break;
}
}
spin_unlock(&dentry->d_lock);
if (all_negative)
shrink_dcache_parent(dentry);
out:
return all_negative;
}
/*
* Trim old(er) caps.
*
* Because we can't cache an inode without one or more caps, we do
* this indirectly: if a cap is unused, we prune its aliases, at which
* point the inode will hopefully get dropped to.
*
* Yes, this is a bit sloppy. Our only real goal here is to respond to
* memory pressure from the MDS, though, so it needn't be perfect.
*/
static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg)
{
struct ceph_mds_session *session = arg;
struct ceph_inode_info *ci = ceph_inode(inode);
int used, wanted, oissued, mine;
if (session->s_trim_caps <= 0)
return -1;
spin_lock(&ci->i_ceph_lock);
mine = cap->issued | cap->implemented;
used = __ceph_caps_used(ci);
wanted = __ceph_caps_file_wanted(ci);
oissued = __ceph_caps_issued_other(ci, cap);
dout("trim_caps_cb %p cap %p mine %s oissued %s used %s wanted %s\n",
inode, cap, ceph_cap_string(mine), ceph_cap_string(oissued),
ceph_cap_string(used), ceph_cap_string(wanted));
if (cap == ci->i_auth_cap) {
if (ci->i_dirty_caps || ci->i_flushing_caps ||
!list_empty(&ci->i_cap_snaps))
goto out;
if ((used | wanted) & CEPH_CAP_ANY_WR)
goto out;
/* Note: it's possible that i_filelock_ref becomes non-zero
* after dropping auth caps. It doesn't hurt because reply
* of lock mds request will re-add auth caps. */
if (atomic_read(&ci->i_filelock_ref) > 0)
goto out;
}
/* The inode has cached pages, but it's no longer used.
* we can safely drop it */
if (wanted == 0 && used == CEPH_CAP_FILE_CACHE &&
!(oissued & CEPH_CAP_FILE_CACHE)) {
used = 0;
oissued = 0;
}
if ((used | wanted) & ~oissued & mine)
goto out; /* we need these caps */
if (oissued) {
/* we aren't the only cap.. just remove us */
__ceph_remove_cap(cap, true);
session->s_trim_caps--;
} else {
struct dentry *dentry;
/* try dropping referring dentries */
spin_unlock(&ci->i_ceph_lock);
dentry = d_find_any_alias(inode);
if (dentry && drop_negative_children(dentry)) {
int count;
dput(dentry);
d_prune_aliases(inode);
count = atomic_read(&inode->i_count);
if (count == 1)
session->s_trim_caps--;
dout("trim_caps_cb %p cap %p pruned, count now %d\n",
inode, cap, count);
} else {
dput(dentry);
}
return 0;
}
out:
spin_unlock(&ci->i_ceph_lock);
return 0;
}
/*
* Trim session cap count down to some max number.
*/
int ceph_trim_caps(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session,
int max_caps)
{
int trim_caps = session->s_nr_caps - max_caps;
dout("trim_caps mds%d start: %d / %d, trim %d\n",
session->s_mds, session->s_nr_caps, max_caps, trim_caps);
if (trim_caps > 0) {
session->s_trim_caps = trim_caps;
iterate_session_caps(session, trim_caps_cb, session);
dout("trim_caps mds%d done: %d / %d, trimmed %d\n",
session->s_mds, session->s_nr_caps, max_caps,
trim_caps - session->s_trim_caps);
session->s_trim_caps = 0;
}
ceph_flush_cap_releases(mdsc, session);
return 0;
}
static int check_caps_flush(struct ceph_mds_client *mdsc,
u64 want_flush_tid)
{
int ret = 1;
spin_lock(&mdsc->cap_dirty_lock);
if (!list_empty(&mdsc->cap_flush_list)) {
struct ceph_cap_flush *cf =
list_first_entry(&mdsc->cap_flush_list,
struct ceph_cap_flush, g_list);
if (cf->tid <= want_flush_tid) {
dout("check_caps_flush still flushing tid "
"%llu <= %llu\n", cf->tid, want_flush_tid);
ret = 0;
}
}
spin_unlock(&mdsc->cap_dirty_lock);
return ret;
}
/*
* flush all dirty inode data to disk.
*
* returns true if we've flushed through want_flush_tid
*/
static void wait_caps_flush(struct ceph_mds_client *mdsc,
u64 want_flush_tid)
{
dout("check_caps_flush want %llu\n", want_flush_tid);
wait_event(mdsc->cap_flushing_wq,
check_caps_flush(mdsc, want_flush_tid));
dout("check_caps_flush ok, flushed thru %llu\n", want_flush_tid);
}
/*
* called under s_mutex
*/
static void ceph_send_cap_releases(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session)
{
struct ceph_msg *msg = NULL;
struct ceph_mds_cap_release *head;
struct ceph_mds_cap_item *item;
struct ceph_osd_client *osdc = &mdsc->fsc->client->osdc;
struct ceph_cap *cap;
LIST_HEAD(tmp_list);
int num_cap_releases;
__le32 barrier, *cap_barrier;
down_read(&osdc->lock);
barrier = cpu_to_le32(osdc->epoch_barrier);
up_read(&osdc->lock);
spin_lock(&session->s_cap_lock);
again:
list_splice_init(&session->s_cap_releases, &tmp_list);
num_cap_releases = session->s_num_cap_releases;
session->s_num_cap_releases = 0;
spin_unlock(&session->s_cap_lock);
while (!list_empty(&tmp_list)) {
if (!msg) {
msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPRELEASE,
PAGE_SIZE, GFP_NOFS, false);
if (!msg)
goto out_err;
head = msg->front.iov_base;
head->num = cpu_to_le32(0);
msg->front.iov_len = sizeof(*head);
msg->hdr.version = cpu_to_le16(2);
msg->hdr.compat_version = cpu_to_le16(1);
}
cap = list_first_entry(&tmp_list, struct ceph_cap,
session_caps);
list_del(&cap->session_caps);
num_cap_releases--;
head = msg->front.iov_base;
le32_add_cpu(&head->num, 1);
item = msg->front.iov_base + msg->front.iov_len;
item->ino = cpu_to_le64(cap->cap_ino);
item->cap_id = cpu_to_le64(cap->cap_id);
item->migrate_seq = cpu_to_le32(cap->mseq);
item->seq = cpu_to_le32(cap->issue_seq);
msg->front.iov_len += sizeof(*item);
ceph_put_cap(mdsc, cap);
if (le32_to_cpu(head->num) == CEPH_CAPS_PER_RELEASE) {
// Append cap_barrier field
cap_barrier = msg->front.iov_base + msg->front.iov_len;
*cap_barrier = barrier;
msg->front.iov_len += sizeof(*cap_barrier);
msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
dout("send_cap_releases mds%d %p\n", session->s_mds, msg);
ceph_con_send(&session->s_con, msg);
msg = NULL;
}
}
BUG_ON(num_cap_releases != 0);
spin_lock(&session->s_cap_lock);
if (!list_empty(&session->s_cap_releases))
goto again;
spin_unlock(&session->s_cap_lock);
if (msg) {
// Append cap_barrier field
cap_barrier = msg->front.iov_base + msg->front.iov_len;
*cap_barrier = barrier;
msg->front.iov_len += sizeof(*cap_barrier);
msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
dout("send_cap_releases mds%d %p\n", session->s_mds, msg);
ceph_con_send(&session->s_con, msg);
}
return;
out_err:
pr_err("send_cap_releases mds%d, failed to allocate message\n",
session->s_mds);
spin_lock(&session->s_cap_lock);
list_splice(&tmp_list, &session->s_cap_releases);
session->s_num_cap_releases += num_cap_releases;
spin_unlock(&session->s_cap_lock);
}
static void ceph_cap_release_work(struct work_struct *work)
{
struct ceph_mds_session *session =
container_of(work, struct ceph_mds_session, s_cap_release_work);
mutex_lock(&session->s_mutex);
if (session->s_state == CEPH_MDS_SESSION_OPEN ||
session->s_state == CEPH_MDS_SESSION_HUNG)
ceph_send_cap_releases(session->s_mdsc, session);
mutex_unlock(&session->s_mutex);
ceph_put_mds_session(session);
}
void ceph_flush_cap_releases(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session)
{
if (mdsc->stopping)
return;
get_session(session);
if (queue_work(mdsc->fsc->cap_wq,
&session->s_cap_release_work)) {
dout("cap release work queued\n");
} else {
ceph_put_mds_session(session);
dout("failed to queue cap release work\n");
}
}
/*
* caller holds session->s_cap_lock
*/
void __ceph_queue_cap_release(struct ceph_mds_session *session,
struct ceph_cap *cap)
{
list_add_tail(&cap->session_caps, &session->s_cap_releases);
session->s_num_cap_releases++;
if (!(session->s_num_cap_releases % CEPH_CAPS_PER_RELEASE))
ceph_flush_cap_releases(session->s_mdsc, session);
}
static void ceph_cap_reclaim_work(struct work_struct *work)
{
struct ceph_mds_client *mdsc =
container_of(work, struct ceph_mds_client, cap_reclaim_work);
int ret = ceph_trim_dentries(mdsc);
if (ret == -EAGAIN)
ceph_queue_cap_reclaim_work(mdsc);
}
void ceph_queue_cap_reclaim_work(struct ceph_mds_client *mdsc)
{
if (mdsc->stopping)
return;
if (queue_work(mdsc->fsc->cap_wq, &mdsc->cap_reclaim_work)) {
dout("caps reclaim work queued\n");
} else {
dout("failed to queue caps release work\n");
}
}
void ceph_reclaim_caps_nr(struct ceph_mds_client *mdsc, int nr)
{
int val;
if (!nr)
return;
val = atomic_add_return(nr, &mdsc->cap_reclaim_pending);
if (!(val % CEPH_CAPS_PER_RELEASE)) {
atomic_set(&mdsc->cap_reclaim_pending, 0);
ceph_queue_cap_reclaim_work(mdsc);
}
}
/*
* requests
*/
int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
struct inode *dir)
{
struct ceph_inode_info *ci = ceph_inode(dir);
struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
struct ceph_mount_options *opt = req->r_mdsc->fsc->mount_options;
size_t size = sizeof(struct ceph_mds_reply_dir_entry);
int order, num_entries;
spin_lock(&ci->i_ceph_lock);
num_entries = ci->i_files + ci->i_subdirs;
spin_unlock(&ci->i_ceph_lock);
num_entries = max(num_entries, 1);
num_entries = min(num_entries, opt->max_readdir);
order = get_order(size * num_entries);
while (order >= 0) {
rinfo->dir_entries = (void*)__get_free_pages(GFP_KERNEL |
__GFP_NOWARN,
order);
if (rinfo->dir_entries)
break;
order--;
}
if (!rinfo->dir_entries)
return -ENOMEM;
num_entries = (PAGE_SIZE << order) / size;
num_entries = min(num_entries, opt->max_readdir);
rinfo->dir_buf_size = PAGE_SIZE << order;
req->r_num_caps = num_entries + 1;
req->r_args.readdir.max_entries = cpu_to_le32(num_entries);
req->r_args.readdir.max_bytes = cpu_to_le32(opt->max_readdir_bytes);
return 0;
}
/*
* Create an mds request.
*/
struct ceph_mds_request *
ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode)
{
struct ceph_mds_request *req = kzalloc(sizeof(*req), GFP_NOFS);
struct timespec64 ts;
if (!req)
return ERR_PTR(-ENOMEM);
mutex_init(&req->r_fill_mutex);
req->r_mdsc = mdsc;
req->r_started = jiffies;
req->r_resend_mds = -1;
INIT_LIST_HEAD(&req->r_unsafe_dir_item);
INIT_LIST_HEAD(&req->r_unsafe_target_item);
req->r_fmode = -1;
kref_init(&req->r_kref);
RB_CLEAR_NODE(&req->r_node);
INIT_LIST_HEAD(&req->r_wait);
init_completion(&req->r_completion);
init_completion(&req->r_safe_completion);
INIT_LIST_HEAD(&req->r_unsafe_item);
ktime_get_coarse_real_ts64(&ts);
req->r_stamp = timespec64_trunc(ts, mdsc->fsc->sb->s_time_gran);
req->r_op = op;
req->r_direct_mode = mode;
return req;
}
/*
* return oldest (lowest) request, tid in request tree, 0 if none.
*
* called under mdsc->mutex.
*/
static struct ceph_mds_request *__get_oldest_req(struct ceph_mds_client *mdsc)
{
if (RB_EMPTY_ROOT(&mdsc->request_tree))
return NULL;
return rb_entry(rb_first(&mdsc->request_tree),
struct ceph_mds_request, r_node);
}
static inline u64 __get_oldest_tid(struct ceph_mds_client *mdsc)
{
return mdsc->oldest_tid;
}
/*
* Build a dentry's path. Allocate on heap; caller must kfree. Based
* on build_path_from_dentry in fs/cifs/dir.c.
*
* If @stop_on_nosnap, generate path relative to the first non-snapped
* inode.
*
* Encode hidden .snap dirs as a double /, i.e.
* foo/.snap/bar -> foo//bar
*/
char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
int stop_on_nosnap)
{
struct dentry *temp;
char *path;
int len, pos;
unsigned seq;
if (!dentry)
return ERR_PTR(-EINVAL);
retry:
len = 0;
seq = read_seqbegin(&rename_lock);
rcu_read_lock();
for (temp = dentry; !IS_ROOT(temp);) {
struct inode *inode = d_inode(temp);
if (inode && ceph_snap(inode) == CEPH_SNAPDIR)
len++; /* slash only */
else if (stop_on_nosnap && inode &&
ceph_snap(inode) == CEPH_NOSNAP)
break;
else
len += 1 + temp->d_name.len;
temp = temp->d_parent;
}
rcu_read_unlock();
if (len)
len--; /* no leading '/' */
path = kmalloc(len+1, GFP_NOFS);
if (!path)
return ERR_PTR(-ENOMEM);
pos = len;
path[pos] = 0; /* trailing null */
rcu_read_lock();
for (temp = dentry; !IS_ROOT(temp) && pos != 0; ) {
struct inode *inode;
spin_lock(&temp->d_lock);
inode = d_inode(temp);
if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
dout("build_path path+%d: %p SNAPDIR\n",
pos, temp);
} else if (stop_on_nosnap && inode &&
ceph_snap(inode) == CEPH_NOSNAP) {
spin_unlock(&temp->d_lock);
break;
} else {
pos -= temp->d_name.len;
if (pos < 0) {
spin_unlock(&temp->d_lock);
break;
}
strncpy(path + pos, temp->d_name.name,
temp->d_name.len);
}
spin_unlock(&temp->d_lock);
if (pos)
path[--pos] = '/';
temp = temp->d_parent;
}
rcu_read_unlock();
if (pos != 0 || read_seqretry(&rename_lock, seq)) {
pr_err("build_path did not end path lookup where "
"expected, namelen is %d, pos is %d\n", len, pos);
/* presumably this is only possible if racing with a
rename of one of the parent directories (we can not
lock the dentries above us to prevent this, but
retrying should be harmless) */
kfree(path);
goto retry;
}
*base = ceph_ino(d_inode(temp));
*plen = len;
dout("build_path on %p %d built %llx '%.*s'\n",
dentry, d_count(dentry), *base, len, path);
return path;
}
/* Duplicate the dentry->d_name.name safely */
static int clone_dentry_name(struct dentry *dentry, const char **ppath,
int *ppathlen)
{
u32 len;
char *name;
retry:
len = READ_ONCE(dentry->d_name.len);
name = kmalloc(len + 1, GFP_NOFS);
if (!name)
return -ENOMEM;
spin_lock(&dentry->d_lock);
if (dentry->d_name.len != len) {
spin_unlock(&dentry->d_lock);
kfree(name);
goto retry;
}
memcpy(name, dentry->d_name.name, len);
spin_unlock(&dentry->d_lock);
name[len] = '\0';
*ppath = name;
*ppathlen = len;
return 0;
}
static int build_dentry_path(struct dentry *dentry, struct inode *dir,
const char **ppath, int *ppathlen, u64 *pino,
bool *pfreepath, bool parent_locked)
{
int ret;
char *path;
rcu_read_lock();
if (!dir)
dir = d_inode_rcu(dentry->d_parent);
if (dir && ceph_snap(dir) == CEPH_NOSNAP) {
*pino = ceph_ino(dir);
rcu_read_unlock();
if (parent_locked) {
*ppath = dentry->d_name.name;
*ppathlen = dentry->d_name.len;
} else {
ret = clone_dentry_name(dentry, ppath, ppathlen);
if (ret)
return ret;
*pfreepath = true;
}
return 0;
}
rcu_read_unlock();
path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
if (IS_ERR(path))
return PTR_ERR(path);
*ppath = path;
*pfreepath = true;
return 0;
}
static int build_inode_path(struct inode *inode,
const char **ppath, int *ppathlen, u64 *pino,
bool *pfreepath)
{
struct dentry *dentry;
char *path;
if (ceph_snap(inode) == CEPH_NOSNAP) {
*pino = ceph_ino(inode);
*ppathlen = 0;
return 0;
}
dentry = d_find_alias(inode);
path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
dput(dentry);
if (IS_ERR(path))
return PTR_ERR(path);
*ppath = path;
*pfreepath = true;
return 0;
}
/*
* request arguments may be specified via an inode *, a dentry *, or
* an explicit ino+path.
*/
static int set_request_path_attr(struct inode *rinode, struct dentry *rdentry,
struct inode *rdiri, const char *rpath,
u64 rino, const char **ppath, int *pathlen,
u64 *ino, bool *freepath, bool parent_locked)
{
int r = 0;
if (rinode) {
r = build_inode_path(rinode, ppath, pathlen, ino, freepath);
dout(" inode %p %llx.%llx\n", rinode, ceph_ino(rinode),
ceph_snap(rinode));
} else if (rdentry) {
r = build_dentry_path(rdentry, rdiri, ppath, pathlen, ino,
freepath, parent_locked);
dout(" dentry %p %llx/%.*s\n", rdentry, *ino, *pathlen,
*ppath);
} else if (rpath || rino) {
*ino = rino;
*ppath = rpath;
*pathlen = rpath ? strlen(rpath) : 0;
dout(" path %.*s\n", *pathlen, rpath);
}
return r;
}
/*
* called under mdsc->mutex
*/
static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req,
int mds, bool drop_cap_releases)
{
struct ceph_msg *msg;
struct ceph_mds_request_head *head;
const char *path1 = NULL;
const char *path2 = NULL;
u64 ino1 = 0, ino2 = 0;
int pathlen1 = 0, pathlen2 = 0;
bool freepath1 = false, freepath2 = false;
int len;
u16 releases;
void *p, *end;
int ret;
ret = set_request_path_attr(req->r_inode, req->r_dentry,
req->r_parent, req->r_path1, req->r_ino1.ino,
&path1, &pathlen1, &ino1, &freepath1,
test_bit(CEPH_MDS_R_PARENT_LOCKED,
&req->r_req_flags));
if (ret < 0) {
msg = ERR_PTR(ret);
goto out;
}
/* If r_old_dentry is set, then assume that its parent is locked */
ret = set_request_path_attr(NULL, req->r_old_dentry,
req->r_old_dentry_dir,
req->r_path2, req->r_ino2.ino,
&path2, &pathlen2, &ino2, &freepath2, true);
if (ret < 0) {
msg = ERR_PTR(ret);
goto out_free1;
}
len = sizeof(*head) +
pathlen1 + pathlen2 + 2*(1 + sizeof(u32) + sizeof(u64)) +
sizeof(struct ceph_timespec);
/* calculate (max) length for cap releases */
len += sizeof(struct ceph_mds_request_release) *
(!!req->r_inode_drop + !!req->r_dentry_drop +
!!req->r_old_inode_drop + !!req->r_old_dentry_drop);
if (req->r_dentry_drop)
len += req->r_dentry->d_name.len;
if (req->r_old_dentry_drop)
len += req->r_old_dentry->d_name.len;
msg = ceph_msg_new2(CEPH_MSG_CLIENT_REQUEST, len, 1, GFP_NOFS, false);
if (!msg) {
msg = ERR_PTR(-ENOMEM);
goto out_free2;
}
msg->hdr.version = cpu_to_le16(2);
msg->hdr.tid = cpu_to_le64(req->r_tid);
head = msg->front.iov_base;
p = msg->front.iov_base + sizeof(*head);
end = msg->front.iov_base + msg->front.iov_len;
head->mdsmap_epoch = cpu_to_le32(mdsc->mdsmap->m_epoch);
head->op = cpu_to_le32(req->r_op);
head->caller_uid = cpu_to_le32(from_kuid(&init_user_ns, req->r_uid));
head->caller_gid = cpu_to_le32(from_kgid(&init_user_ns, req->r_gid));
head->args = req->r_args;
ceph_encode_filepath(&p, end, ino1, path1);
ceph_encode_filepath(&p, end, ino2, path2);
/* make note of release offset, in case we need to replay */
req->r_request_release_offset = p - msg->front.iov_base;
/* cap releases */
releases = 0;
if (req->r_inode_drop)
releases += ceph_encode_inode_release(&p,
req->r_inode ? req->r_inode : d_inode(req->r_dentry),
mds, req->r_inode_drop, req->r_inode_unless, 0);
if (req->r_dentry_drop)
releases += ceph_encode_dentry_release(&p, req->r_dentry,
req->r_parent, mds, req->r_dentry_drop,
req->r_dentry_unless);
if (req->r_old_dentry_drop)
releases += ceph_encode_dentry_release(&p, req->r_old_dentry,
req->r_old_dentry_dir, mds,
req->r_old_dentry_drop,
req->r_old_dentry_unless);
if (req->r_old_inode_drop)
releases += ceph_encode_inode_release(&p,
d_inode(req->r_old_dentry),
mds, req->r_old_inode_drop, req->r_old_inode_unless, 0);
if (drop_cap_releases) {
releases = 0;
p = msg->front.iov_base + req->r_request_release_offset;
}
head->num_releases = cpu_to_le16(releases);
/* time stamp */
{
struct ceph_timespec ts;
ceph_encode_timespec64(&ts, &req->r_stamp);
ceph_encode_copy(&p, &ts, sizeof(ts));
}
BUG_ON(p > end);
msg->front.iov_len = p - msg->front.iov_base;
msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
if (req->r_pagelist) {
struct ceph_pagelist *pagelist = req->r_pagelist;
ceph_msg_data_add_pagelist(msg, pagelist);
msg->hdr.data_len = cpu_to_le32(pagelist->length);
} else {
msg->hdr.data_len = 0;
}
msg->hdr.data_off = cpu_to_le16(0);
out_free2:
if (freepath2)
kfree((char *)path2);
out_free1:
if (freepath1)
kfree((char *)path1);
out:
return msg;
}
/*
* called under mdsc->mutex if error, under no mutex if
* success.
*/
static void complete_request(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req)
{
if (req->r_callback)
req->r_callback(mdsc, req);
else
complete_all(&req->r_completion);
}
/*
* called under mdsc->mutex
*/
static int __prepare_send_request(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req,
int mds, bool drop_cap_releases)
{
struct ceph_mds_request_head *rhead;
struct ceph_msg *msg;
int flags = 0;
req->r_attempts++;
if (req->r_inode) {
struct ceph_cap *cap =
ceph_get_cap_for_mds(ceph_inode(req->r_inode), mds);
if (cap)
req->r_sent_on_mseq = cap->mseq;
else
req->r_sent_on_mseq = -1;
}
dout("prepare_send_request %p tid %lld %s (attempt %d)\n", req,
req->r_tid, ceph_mds_op_name(req->r_op), req->r_attempts);
if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) {
void *p;
/*
* Replay. Do not regenerate message (and rebuild
* paths, etc.); just use the original message.
* Rebuilding paths will break for renames because
* d_move mangles the src name.
*/
msg = req->r_request;
rhead = msg->front.iov_base;
flags = le32_to_cpu(rhead->flags);
flags |= CEPH_MDS_FLAG_REPLAY;
rhead->flags = cpu_to_le32(flags);
if (req->r_target_inode)
rhead->ino = cpu_to_le64(ceph_ino(req->r_target_inode));
rhead->num_retry = req->r_attempts - 1;
/* remove cap/dentry releases from message */
rhead->num_releases = 0;
/* time stamp */
p = msg->front.iov_base + req->r_request_release_offset;
{
struct ceph_timespec ts;
ceph_encode_timespec64(&ts, &req->r_stamp);
ceph_encode_copy(&p, &ts, sizeof(ts));
}
msg->front.iov_len = p - msg->front.iov_base;
msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
return 0;
}
if (req->r_request) {
ceph_msg_put(req->r_request);
req->r_request = NULL;
}
msg = create_request_message(mdsc, req, mds, drop_cap_releases);
if (IS_ERR(msg)) {
req->r_err = PTR_ERR(msg);
return PTR_ERR(msg);
}
req->r_request = msg;
rhead = msg->front.iov_base;
rhead->oldest_client_tid = cpu_to_le64(__get_oldest_tid(mdsc));
if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags))
flags |= CEPH_MDS_FLAG_REPLAY;
if (req->r_parent)
flags |= CEPH_MDS_FLAG_WANT_DENTRY;
rhead->flags = cpu_to_le32(flags);
rhead->num_fwd = req->r_num_fwd;
rhead->num_retry = req->r_attempts - 1;
rhead->ino = 0;
dout(" r_parent = %p\n", req->r_parent);
return 0;
}
/*
* send request, or put it on the appropriate wait list.
*/
static void __do_request(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req)
{
struct ceph_mds_session *session = NULL;
int mds = -1;
int err = 0;
if (req->r_err || test_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags)) {
if (test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags))
__unregister_request(mdsc, req);
return;
}
if (req->r_timeout &&
time_after_eq(jiffies, req->r_started + req->r_timeout)) {
dout("do_request timed out\n");
err = -EIO;
goto finish;
}
if (READ_ONCE(mdsc->fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) {
dout("do_request forced umount\n");
err = -EIO;
goto finish;
}
if (READ_ONCE(mdsc->fsc->mount_state) == CEPH_MOUNT_MOUNTING) {
if (mdsc->mdsmap_err) {
err = mdsc->mdsmap_err;
dout("do_request mdsmap err %d\n", err);
goto finish;
}
if (mdsc->mdsmap->m_epoch == 0) {
dout("do_request no mdsmap, waiting for map\n");
list_add(&req->r_wait, &mdsc->waiting_for_map);
return;
}
if (!(mdsc->fsc->mount_options->flags &
CEPH_MOUNT_OPT_MOUNTWAIT) &&
!ceph_mdsmap_is_cluster_available(mdsc->mdsmap)) {
err = -ENOENT;
pr_info("probably no mds server is up\n");
goto finish;
}
}
put_request_session(req);
mds = __choose_mds(mdsc, req);
if (mds < 0 ||
ceph_mdsmap_get_state(mdsc->mdsmap, mds) < CEPH_MDS_STATE_ACTIVE) {
dout("do_request no mds or not active, waiting for map\n");
list_add(&req->r_wait, &mdsc->waiting_for_map);
return;
}
/* get, open session */
session = __ceph_lookup_mds_session(mdsc, mds);
if (!session) {
session = register_session(mdsc, mds);
if (IS_ERR(session)) {
err = PTR_ERR(session);
goto finish;
}
}
req->r_session = get_session(session);
dout("do_request mds%d session %p state %s\n", mds, session,
ceph_session_state_name(session->s_state));
if (session->s_state != CEPH_MDS_SESSION_OPEN &&
session->s_state != CEPH_MDS_SESSION_HUNG) {
if (session->s_state == CEPH_MDS_SESSION_REJECTED) {
err = -EACCES;
goto out_session;
}
if (session->s_state == CEPH_MDS_SESSION_NEW ||
session->s_state == CEPH_MDS_SESSION_CLOSING)
__open_session(mdsc, session);
list_add(&req->r_wait, &session->s_waiting);
goto out_session;
}
/* send request */
req->r_resend_mds = -1; /* forget any previous mds hint */
if (req->r_request_started == 0) /* note request start time */
req->r_request_started = jiffies;
err = __prepare_send_request(mdsc, req, mds, false);
if (!err) {
ceph_msg_get(req->r_request);
ceph_con_send(&session->s_con, req->r_request);
}
out_session:
ceph_put_mds_session(session);
finish:
if (err) {
dout("__do_request early error %d\n", err);
req->r_err = err;
complete_request(mdsc, req);
__unregister_request(mdsc, req);
}
return;
}
/*
* called under mdsc->mutex
*/
static void __wake_requests(struct ceph_mds_client *mdsc,
struct list_head *head)
{
struct ceph_mds_request *req;
LIST_HEAD(tmp_list);
list_splice_init(head, &tmp_list);
while (!list_empty(&tmp_list)) {
req = list_entry(tmp_list.next,
struct ceph_mds_request, r_wait);
list_del_init(&req->r_wait);
dout(" wake request %p tid %llu\n", req, req->r_tid);
__do_request(mdsc, req);
}
}
/*
* Wake up threads with requests pending for @mds, so that they can
* resubmit their requests to a possibly different mds.
*/
static void kick_requests(struct ceph_mds_client *mdsc, int mds)
{
struct ceph_mds_request *req;
struct rb_node *p = rb_first(&mdsc->request_tree);
dout("kick_requests mds%d\n", mds);
while (p) {
req = rb_entry(p, struct ceph_mds_request, r_node);
p = rb_next(p);
if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags))
continue;
if (req->r_attempts > 0)
continue; /* only new requests */
if (req->r_session &&
req->r_session->s_mds == mds) {
dout(" kicking tid %llu\n", req->r_tid);
list_del_init(&req->r_wait);
__do_request(mdsc, req);
}
}
}
void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req)
{
dout("submit_request on %p\n", req);
mutex_lock(&mdsc->mutex);
__register_request(mdsc, req, NULL);
__do_request(mdsc, req);
mutex_unlock(&mdsc->mutex);
}
/*
* Synchrously perform an mds request. Take care of all of the
* session setup, forwarding, retry details.
*/
int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
struct inode *dir,
struct ceph_mds_request *req)
{
int err;
dout("do_request on %p\n", req);
/* take CAP_PIN refs for r_inode, r_parent, r_old_dentry */
if (req->r_inode)
ceph_get_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
if (req->r_parent)
ceph_get_cap_refs(ceph_inode(req->r_parent), CEPH_CAP_PIN);
if (req->r_old_dentry_dir)
ceph_get_cap_refs(ceph_inode(req->r_old_dentry_dir),
CEPH_CAP_PIN);
/* issue */
mutex_lock(&mdsc->mutex);
__register_request(mdsc, req, dir);
__do_request(mdsc, req);
if (req->r_err) {
err = req->r_err;
goto out;
}
/* wait */
mutex_unlock(&mdsc->mutex);
dout("do_request waiting\n");
if (!req->r_timeout && req->r_wait_for_completion) {
err = req->r_wait_for_completion(mdsc, req);
} else {
long timeleft = wait_for_completion_killable_timeout(
&req->r_completion,
ceph_timeout_jiffies(req->r_timeout));
if (timeleft > 0)
err = 0;
else if (!timeleft)
err = -EIO; /* timed out */
else
err = timeleft; /* killed */
}
dout("do_request waited, got %d\n", err);
mutex_lock(&mdsc->mutex);
/* only abort if we didn't race with a real reply */
if (test_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags)) {
err = le32_to_cpu(req->r_reply_info.head->result);
} else if (err < 0) {
dout("aborted request %lld with %d\n", req->r_tid, err);
/*
* ensure we aren't running concurrently with
* ceph_fill_trace or ceph_readdir_prepopulate, which
* rely on locks (dir mutex) held by our caller.
*/
mutex_lock(&req->r_fill_mutex);
req->r_err = err;
set_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags);
mutex_unlock(&req->r_fill_mutex);
if (req->r_parent &&
(req->r_op & CEPH_MDS_OP_WRITE))
ceph_invalidate_dir_request(req);
} else {
err = req->r_err;
}
out:
mutex_unlock(&mdsc->mutex);
dout("do_request %p done, result %d\n", req, err);
return err;
}
/*
* Invalidate dir's completeness, dentry lease state on an aborted MDS
* namespace request.
*/
void ceph_invalidate_dir_request(struct ceph_mds_request *req)
{
struct inode *dir = req->r_parent;
struct inode *old_dir = req->r_old_dentry_dir;
dout("invalidate_dir_request %p %p (complete, lease(s))\n", dir, old_dir);
ceph_dir_clear_complete(dir);
if (old_dir)
ceph_dir_clear_complete(old_dir);
if (req->r_dentry)
ceph_invalidate_dentry_lease(req->r_dentry);
if (req->r_old_dentry)
ceph_invalidate_dentry_lease(req->r_old_dentry);
}
/*
* Handle mds reply.
*
* We take the session mutex and parse and process the reply immediately.
* This preserves the logical ordering of replies, capabilities, etc., sent
* by the MDS as they are applied to our local cache.
*/
static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
{
struct ceph_mds_client *mdsc = session->s_mdsc;
struct ceph_mds_request *req;
struct ceph_mds_reply_head *head = msg->front.iov_base;
struct ceph_mds_reply_info_parsed *rinfo; /* parsed reply info */
struct ceph_snap_realm *realm;
u64 tid;
int err, result;
int mds = session->s_mds;
if (msg->front.iov_len < sizeof(*head)) {
pr_err("mdsc_handle_reply got corrupt (short) reply\n");
ceph_msg_dump(msg);
return;
}
/* get request, session */
tid = le64_to_cpu(msg->hdr.tid);
mutex_lock(&mdsc->mutex);
req = lookup_get_request(mdsc, tid);
if (!req) {
dout("handle_reply on unknown tid %llu\n", tid);
mutex_unlock(&mdsc->mutex);
return;
}
dout("handle_reply %p\n", req);
/* correct session? */
if (req->r_session != session) {
pr_err("mdsc_handle_reply got %llu on session mds%d"
" not mds%d\n", tid, session->s_mds,
req->r_session ? req->r_session->s_mds : -1);
mutex_unlock(&mdsc->mutex);
goto out;
}
/* dup? */
if ((test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags) && !head->safe) ||
(test_bit(CEPH_MDS_R_GOT_SAFE, &req->r_req_flags) && head->safe)) {
pr_warn("got a dup %s reply on %llu from mds%d\n",
head->safe ? "safe" : "unsafe", tid, mds);
mutex_unlock(&mdsc->mutex);
goto out;
}
if (test_bit(CEPH_MDS_R_GOT_SAFE, &req->r_req_flags)) {
pr_warn("got unsafe after safe on %llu from mds%d\n",
tid, mds);
mutex_unlock(&mdsc->mutex);
goto out;
}
result = le32_to_cpu(head->result);
/*
* Handle an ESTALE
* if we're not talking to the authority, send to them
* if the authority has changed while we weren't looking,
* send to new authority
* Otherwise we just have to return an ESTALE
*/
if (result == -ESTALE) {
dout("got ESTALE on request %llu\n", req->r_tid);
req->r_resend_mds = -1;
if (req->r_direct_mode != USE_AUTH_MDS) {
dout("not using auth, setting for that now\n");
req->r_direct_mode = USE_AUTH_MDS;
__do_request(mdsc, req);
mutex_unlock(&mdsc->mutex);
goto out;
} else {
int mds = __choose_mds(mdsc, req);
if (mds >= 0 && mds != req->r_session->s_mds) {
dout("but auth changed, so resending\n");
__do_request(mdsc, req);
mutex_unlock(&mdsc->mutex);
goto out;
}
}
dout("have to return ESTALE on request %llu\n", req->r_tid);
}
if (head->safe) {
set_bit(CEPH_MDS_R_GOT_SAFE, &req->r_req_flags);
__unregister_request(mdsc, req);
if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) {
/*
* We already handled the unsafe response, now do the
* cleanup. No need to examine the response; the MDS
* doesn't include any result info in the safe
* response. And even if it did, there is nothing
* useful we could do with a revised return value.
*/
dout("got safe reply %llu, mds%d\n", tid, mds);
/* last unsafe request during umount? */
if (mdsc->stopping && !__get_oldest_req(mdsc))
complete_all(&mdsc->safe_umount_waiters);
mutex_unlock(&mdsc->mutex);
goto out;
}
} else {
set_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags);
list_add_tail(&req->r_unsafe_item, &req->r_session->s_unsafe);
if (req->r_unsafe_dir) {
struct ceph_inode_info *ci =
ceph_inode(req->r_unsafe_dir);
spin_lock(&ci->i_unsafe_lock);
list_add_tail(&req->r_unsafe_dir_item,
&ci->i_unsafe_dirops);
spin_unlock(&ci->i_unsafe_lock);
}
}
dout("handle_reply tid %lld result %d\n", tid, result);
rinfo = &req->r_reply_info;
if (test_bit(CEPHFS_FEATURE_REPLY_ENCODING, &session->s_features))
err = parse_reply_info(msg, rinfo, (u64)-1);
else
err = parse_reply_info(msg, rinfo, session->s_con.peer_features);
mutex_unlock(&mdsc->mutex);
mutex_lock(&session->s_mutex);
if (err < 0) {
pr_err("mdsc_handle_reply got corrupt reply mds%d(tid:%lld)\n", mds, tid);
ceph_msg_dump(msg);
goto out_err;
}
/* snap trace */
realm = NULL;
if (rinfo->snapblob_len) {
down_write(&mdsc->snap_rwsem);
ceph_update_snap_trace(mdsc, rinfo->snapblob,
rinfo->snapblob + rinfo->snapblob_len,
le32_to_cpu(head->op) == CEPH_MDS_OP_RMSNAP,
&realm);
downgrade_write(&mdsc->snap_rwsem);
} else {
down_read(&mdsc->snap_rwsem);
}
/* insert trace into our cache */
mutex_lock(&req->r_fill_mutex);
current->journal_info = req;
err = ceph_fill_trace(mdsc->fsc->sb, req);
if (err == 0) {
if (result == 0 && (req->r_op == CEPH_MDS_OP_READDIR ||
req->r_op == CEPH_MDS_OP_LSSNAP))
ceph_readdir_prepopulate(req, req->r_session);
}
current->journal_info = NULL;
mutex_unlock(&req->r_fill_mutex);
up_read(&mdsc->snap_rwsem);
if (realm)
ceph_put_snap_realm(mdsc, realm);
if (err == 0) {
if (req->r_target_inode &&
test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) {
struct ceph_inode_info *ci =
ceph_inode(req->r_target_inode);
spin_lock(&ci->i_unsafe_lock);
list_add_tail(&req->r_unsafe_target_item,
&ci->i_unsafe_iops);
spin_unlock(&ci->i_unsafe_lock);
}
ceph_unreserve_caps(mdsc, &req->r_caps_reservation);
}
out_err:
mutex_lock(&mdsc->mutex);
if (!test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags)) {
if (err) {
req->r_err = err;
} else {
req->r_reply = ceph_msg_get(msg);
set_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags);
}
} else {
dout("reply arrived after request %lld was aborted\n", tid);
}
mutex_unlock(&mdsc->mutex);
mutex_unlock(&session->s_mutex);
/* kick calling process */
complete_request(mdsc, req);
out:
ceph_mdsc_put_request(req);
return;
}
/*
* handle mds notification that our request has been forwarded.
*/
static void handle_forward(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session,
struct ceph_msg *msg)
{
struct ceph_mds_request *req;
u64 tid =