linux/fs/ceph/mds_client.c

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#include "ceph_debug.h"
#include <linux/wait.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <linux/sched.h>
#include "mds_client.h"
#include "mon_client.h"
#include "super.h"
#include "messenger.h"
#include "decode.h"
#include "auth.h"
#include "pagelist.h"
/*
* 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.
*/
static void __wake_requests(struct ceph_mds_client *mdsc,
struct list_head *head);
const static struct ceph_connection_operations mds_con_ops;
/*
* mds reply parsing
*/
/*
* parse individual inode info
*/
static int parse_reply_info_in(void **p, void *end,
struct ceph_mds_reply_info_in *info)
{
int err = -EIO;
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_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;
return 0;
bad:
return err;
}
/*
* 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)
{
int err;
if (info->head->is_dentry) {
err = parse_reply_info_in(p, end, &info->diri);
if (err < 0)
goto out_bad;
if (unlikely(*p + sizeof(*info->dirfrag) > end))
goto bad;
info->dirfrag = *p;
*p += sizeof(*info->dirfrag) +
sizeof(u32)*le32_to_cpu(info->dirfrag->ndist);
if (unlikely(*p > end))
goto 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;
info->dlease = *p;
*p += sizeof(*info->dlease);
}
if (info->head->is_target) {
err = parse_reply_info_in(p, end, &info->targeti);
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_dir(void **p, void *end,
struct ceph_mds_reply_info_parsed *info)
{
u32 num, i = 0;
int err;
info->dir_dir = *p;
if (*p + sizeof(*info->dir_dir) > end)
goto bad;
*p += sizeof(*info->dir_dir) +
sizeof(u32)*le32_to_cpu(info->dir_dir->ndist);
if (*p > end)
goto bad;
ceph_decode_need(p, end, sizeof(num) + 2, bad);
num = ceph_decode_32(p);
info->dir_end = ceph_decode_8(p);
info->dir_complete = ceph_decode_8(p);
if (num == 0)
goto done;
/* alloc large array */
info->dir_nr = num;
info->dir_in = kcalloc(num, sizeof(*info->dir_in) +
sizeof(*info->dir_dname) +
sizeof(*info->dir_dname_len) +
sizeof(*info->dir_dlease),
GFP_NOFS);
if (info->dir_in == NULL) {
err = -ENOMEM;
goto out_bad;
}
info->dir_dname = (void *)(info->dir_in + num);
info->dir_dname_len = (void *)(info->dir_dname + num);
info->dir_dlease = (void *)(info->dir_dname_len + num);
while (num) {
/* dentry */
ceph_decode_need(p, end, sizeof(u32)*2, bad);
info->dir_dname_len[i] = ceph_decode_32(p);
ceph_decode_need(p, end, info->dir_dname_len[i], bad);
info->dir_dname[i] = *p;
*p += info->dir_dname_len[i];
dout("parsed dir dname '%.*s'\n", info->dir_dname_len[i],
info->dir_dname[i]);
info->dir_dlease[i] = *p;
*p += sizeof(struct ceph_mds_reply_lease);
/* inode */
err = parse_reply_info_in(p, end, &info->dir_in[i]);
if (err < 0)
goto out_bad;
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 entire mds reply
*/
static int parse_reply_info(struct ceph_msg *msg,
struct ceph_mds_reply_info_parsed *info)
{
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) {
err = parse_reply_info_trace(&p, p+len, info);
if (err < 0)
goto out_bad;
}
/* dir content */
ceph_decode_32_safe(&p, end, len, bad);
if (len > 0) {
err = parse_reply_info_dir(&p, p+len, info);
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)
{
kfree(info->dir_in);
}
/*
* sessions
*/
static const char *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";
default: return "???";
}
}
static struct ceph_mds_session *get_session(struct ceph_mds_session *s)
{
if (atomic_inc_not_zero(&s->s_ref)) {
dout("mdsc get_session %p %d -> %d\n", s,
atomic_read(&s->s_ref)-1, atomic_read(&s->s_ref));
return s;
} else {
dout("mdsc get_session %p 0 -- FAIL", s);
return NULL;
}
}
void ceph_put_mds_session(struct ceph_mds_session *s)
{
dout("mdsc put_session %p %d -> %d\n", s,
atomic_read(&s->s_ref), atomic_read(&s->s_ref)-1);
if (atomic_dec_and_test(&s->s_ref)) {
if (s->s_authorizer)
s->s_mdsc->client->monc.auth->ops->destroy_authorizer(
s->s_mdsc->client->monc.auth, s->s_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] == NULL)
return NULL;
session = mdsc->sessions[mds];
dout("lookup_mds_session %p %d\n", session,
atomic_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)
return false;
return mdsc->sessions[mds];
}
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;
s = kzalloc(sizeof(*s), GFP_NOFS);
if (!s)
return ERR_PTR(-ENOMEM);
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(mdsc->client->msgr, &s->s_con);
s->s_con.private = s;
s->s_con.ops = &mds_con_ops;
s->s_con.peer_name.type = CEPH_ENTITY_TYPE_MDS;
s->s_con.peer_name.num = cpu_to_le64(mds);
spin_lock_init(&s->s_cap_lock);
s->s_cap_gen = 0;
s->s_cap_ttl = 0;
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;
atomic_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_iterator = NULL;
INIT_LIST_HEAD(&s->s_cap_releases);
INIT_LIST_HEAD(&s->s_cap_releases_done);
INIT_LIST_HEAD(&s->s_cap_flushing);
INIT_LIST_HEAD(&s->s_cap_snaps_flushing);
dout("register_session mds%d\n", mds);
if (mds >= mdsc->max_sessions) {
int newmax = 1 << get_count_order(mds+1);
struct ceph_mds_session **sa;
dout("register_session realloc to %d\n", newmax);
sa = kcalloc(newmax, sizeof(void *), GFP_NOFS);
if (sa == NULL)
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;
}
mdsc->sessions[mds] = s;
atomic_inc(&s->s_ref); /* one ref to sessions[], one to caller */
ceph_con_open(&s->s_con, 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;
ceph_con_close(&s->s_con);
ceph_put_mds_session(s);
}
/*
* 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);
if (req->r_request)
ceph_msg_put(req->r_request);
if (req->r_reply) {
ceph_msg_put(req->r_reply);
destroy_reply_info(&req->r_reply_info);
}
if (req->r_inode) {
ceph_put_cap_refs(ceph_inode(req->r_inode),
CEPH_CAP_PIN);
iput(req->r_inode);
}
if (req->r_locked_dir)
ceph_put_cap_refs(ceph_inode(req->r_locked_dir),
CEPH_CAP_PIN);
if (req->r_target_inode)
iput(req->r_target_inode);
if (req->r_dentry)
dput(req->r_dentry);
if (req->r_old_dentry) {
ceph_put_cap_refs(
ceph_inode(req->r_old_dentry->d_parent->d_inode),
CEPH_CAP_PIN);
dput(req->r_old_dentry);
}
kfree(req->r_path1);
kfree(req->r_path2);
put_request_session(req);
ceph_unreserve_caps(&req->r_caps_reservation);
kfree(req);
}
/*
* lookup session, bump ref if found.
*
* called under mdsc->mutex.
*/
static struct ceph_mds_request *__lookup_request(struct ceph_mds_client *mdsc,
u64 tid)
{
struct ceph_mds_request *req;
struct rb_node *n = mdsc->request_tree.rb_node;
while (n) {
req = rb_entry(n, struct ceph_mds_request, r_node);
if (tid < req->r_tid)
n = n->rb_left;
else if (tid > req->r_tid)
n = n->rb_right;
else {
ceph_mdsc_get_request(req);
return req;
}
}
return NULL;
}
static void __insert_request(struct ceph_mds_client *mdsc,
struct ceph_mds_request *new)
{
struct rb_node **p = &mdsc->request_tree.rb_node;
struct rb_node *parent = NULL;
struct ceph_mds_request *req = NULL;
while (*p) {
parent = *p;
req = rb_entry(parent, struct ceph_mds_request, r_node);
if (new->r_tid < req->r_tid)
p = &(*p)->rb_left;
else if (new->r_tid > req->r_tid)
p = &(*p)->rb_right;
else
BUG();
}
rb_link_node(&new->r_node, parent, p);
rb_insert_color(&new->r_node, &mdsc->request_tree);
}
/*
* 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)
{
req->r_tid = ++mdsc->last_tid;
if (req->r_num_caps)
ceph_reserve_caps(&req->r_caps_reservation, req->r_num_caps);
dout("__register_request %p tid %lld\n", req, req->r_tid);
ceph_mdsc_get_request(req);
__insert_request(mdsc, req);
if (dir) {
struct ceph_inode_info *ci = ceph_inode(dir);
spin_lock(&ci->i_unsafe_lock);
req->r_unsafe_dir = dir;
list_add_tail(&req->r_unsafe_dir_item, &ci->i_unsafe_dirops);
spin_unlock(&ci->i_unsafe_lock);
}
}
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);
rb_erase(&req->r_node, &mdsc->request_tree);
RB_CLEAR_NODE(&req->r_node);
if (req->r_unsafe_dir) {
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);
}
ceph_mdsc_put_request(req);
}
/*
* 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 = req->r_direct_is_hash;
/*
* 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) {
inode = req->r_inode;
} else if (req->r_dentry) {
if (req->r_dentry->d_inode) {
inode = req->r_dentry->d_inode;
} else {
inode = req->r_dentry->d_parent->d_inode;
hash = req->r_dentry->d_name.hash;
is_hash = true;
}
}
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, frag.mds,
(int)r, frag.ndist);
return mds;
}
/* 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);
return mds;
}
}
}
spin_lock(&inode->i_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(&inode->i_lock);
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(&inode->i_lock);
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), 0, 0, NULL);
if (IS_ERR(msg)) {
pr_err("create_session_msg ENOMEM creating msg\n");
return ERR_PTR(PTR_ERR(msg));
}
h = msg->front.iov_base;
h->op = cpu_to_le32(op);
h->seq = cpu_to_le64(seq);
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;
int err = 0;
/* 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_msg(CEPH_SESSION_REQUEST_OPEN, session->s_seq);
if (IS_ERR(msg)) {
err = PTR_ERR(msg);
goto out;
}
ceph_con_send(&session->s_con, msg);
out:
return 0;
}
/*
* session caps
*/
/*
* Free preallocated cap messages assigned to this session
*/
static void cleanup_cap_releases(struct ceph_mds_session *session)
{
struct ceph_msg *msg;
spin_lock(&session->s_cap_lock);
while (!list_empty(&session->s_cap_releases)) {
msg = list_first_entry(&session->s_cap_releases,
struct ceph_msg, list_head);
list_del_init(&msg->list_head);
ceph_msg_put(msg);
}
while (!list_empty(&session->s_cap_releases_done)) {
msg = list_first_entry(&session->s_cap_releases_done,
struct ceph_msg, list_head);
list_del_init(&msg->list_head);
ceph_msg_put(msg);
}
spin_unlock(&session->s_cap_lock);
}
/*
* 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(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 == NULL) {
dout("iterate_session_caps finishing cap %p removal\n",
cap);
BUG_ON(cap->session != session);
list_del_init(&cap->session_caps);
session->s_nr_caps--;
cap->session = NULL;
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);
if (last_inode)
iput(last_inode);
if (old_cap)
ceph_put_cap(old_cap);
return ret;
}
static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
void *arg)
{
struct ceph_inode_info *ci = ceph_inode(inode);
dout("removing cap %p, ci is %p, inode is %p\n",
cap, ci, &ci->vfs_inode);
ceph_remove_cap(cap);
return 0;
}
/*
* caller must hold session s_mutex
*/
static void remove_session_caps(struct ceph_mds_session *session)
{
dout("remove_session_caps on %p\n", session);
iterate_session_caps(session, remove_session_caps_cb, NULL);
BUG_ON(session->s_nr_caps > 0);
cleanup_cap_releases(session);
}
/*
* 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);
wake_up(&ci->i_cap_wq);
if (arg) {
spin_lock(&inode->i_lock);
ci->i_wanted_max_size = 0;
ci->i_requested_max_size = 0;
spin_unlock(&inode->i_lock);
}
return 0;
}
static void wake_up_session_caps(struct ceph_mds_session *session,
int reconnect)
{
dout("wake_up_session_caps %p mds%d\n", session, session->s_mds);
iterate_session_caps(session, wake_up_session_cb,
(void *)(unsigned long)reconnect);
}
/*
* 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 (IS_ERR(msg))
return PTR_ERR(msg);
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 && (session->s_cap_ttl == 0 ||
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, 0);
}
/*
* send a session close request
*/
static int request_close_session(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session)
{
struct ceph_msg *msg;
int err = 0;
dout("request_close_session mds%d state %s seq %lld\n",
session->s_mds, session_state_name(session->s_state),
session->s_seq);
msg = create_session_msg(CEPH_SESSION_REQUEST_CLOSE, session->s_seq);
if (IS_ERR(msg))
err = PTR_ERR(msg);
else
ceph_con_send(&session->s_con, msg);
return err;
}
/*
* 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);
}
/*
* 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, oissued, mine;
if (session->s_trim_caps <= 0)
return -1;
spin_lock(&inode->i_lock);
mine = cap->issued | cap->implemented;
used = __ceph_caps_used(ci);
oissued = __ceph_caps_issued_other(ci, cap);
dout("trim_caps_cb %p cap %p mine %s oissued %s used %s\n",
inode, cap, ceph_cap_string(mine), ceph_cap_string(oissued),
ceph_cap_string(used));
if (ci->i_dirty_caps)
goto out; /* dirty caps */
if ((used & ~oissued) & mine)
goto out; /* we need these caps */
session->s_trim_caps--;
if (oissued) {
/* we aren't the only cap.. just remove us */
__ceph_remove_cap(cap);
} else {
/* try to drop referring dentries */
spin_unlock(&inode->i_lock);
d_prune_aliases(inode);
dout("trim_caps_cb %p cap %p pruned, count now %d\n",
inode, cap, atomic_read(&inode->i_count));
return 0;
}
out:
spin_unlock(&inode->i_lock);
return 0;
}
/*
* Trim session cap count down to some max number.
*/
static int 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;
}
return 0;
}
/*
* Allocate cap_release messages. If there is a partially full message
* in the queue, try to allocate enough to cover it's remainder, so that
* we can send it immediately.
*
* Called under s_mutex.
*/
static int add_cap_releases(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session,
int extra)
{
struct ceph_msg *msg;
struct ceph_mds_cap_release *head;
int err = -ENOMEM;
if (extra < 0)
extra = mdsc->client->mount_args->cap_release_safety;
spin_lock(&session->s_cap_lock);
if (!list_empty(&session->s_cap_releases)) {
msg = list_first_entry(&session->s_cap_releases,
struct ceph_msg,
list_head);
head = msg->front.iov_base;
extra += CEPH_CAPS_PER_RELEASE - le32_to_cpu(head->num);
}
while (session->s_num_cap_releases < session->s_nr_caps + extra) {
spin_unlock(&session->s_cap_lock);
msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPRELEASE, PAGE_CACHE_SIZE,
0, 0, NULL);
if (!msg)
goto out_unlocked;
dout("add_cap_releases %p msg %p now %d\n", session, msg,
(int)msg->front.iov_len);
head = msg->front.iov_base;
head->num = cpu_to_le32(0);
msg->front.iov_len = sizeof(*head);
spin_lock(&session->s_cap_lock);
list_add(&msg->list_head, &session->s_cap_releases);
session->s_num_cap_releases += CEPH_CAPS_PER_RELEASE;
}
if (!list_empty(&session->s_cap_releases)) {
msg = list_first_entry(&session->s_cap_releases,
struct ceph_msg,
list_head);
head = msg->front.iov_base;
if (head->num) {
dout(" queueing non-full %p (%d)\n", msg,
le32_to_cpu(head->num));
list_move_tail(&msg->list_head,
&session->s_cap_releases_done);
session->s_num_cap_releases -=
CEPH_CAPS_PER_RELEASE - le32_to_cpu(head->num);
}
}
err = 0;
spin_unlock(&session->s_cap_lock);
out_unlocked:
return err;
}
/*
* flush all dirty inode data to disk.
*
* returns true if we've flushed through want_flush_seq
*/
static int check_cap_flush(struct ceph_mds_client *mdsc, u64 want_flush_seq)
{
int mds, ret = 1;
dout("check_cap_flush want %lld\n", want_flush_seq);
mutex_lock(&mdsc->mutex);
for (mds = 0; ret && mds < mdsc->max_sessions; mds++) {
struct ceph_mds_session *session = mdsc->sessions[mds];
if (!session)
continue;
get_session(session);
mutex_unlock(&mdsc->mutex);
mutex_lock(&session->s_mutex);
if (!list_empty(&session->s_cap_flushing)) {
struct ceph_inode_info *ci =
list_entry(session->s_cap_flushing.next,
struct ceph_inode_info,
i_flushing_item);
struct inode *inode = &ci->vfs_inode;
spin_lock(&inode->i_lock);
if (ci->i_cap_flush_seq <= want_flush_seq) {
dout("check_cap_flush still flushing %p "
"seq %lld <= %lld to mds%d\n", inode,
ci->i_cap_flush_seq, want_flush_seq,
session->s_mds);
ret = 0;
}
spin_unlock(&inode->i_lock);
}
mutex_unlock(&session->s_mutex);
ceph_put_mds_session(session);
if (!ret)
return ret;
mutex_lock(&mdsc->mutex);
}
mutex_unlock(&mdsc->mutex);
dout("check_cap_flush ok, flushed thru %lld\n", want_flush_seq);
return ret;
}
/*
* called under s_mutex
*/
static void send_cap_releases(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session)
{
struct ceph_msg *msg;
dout("send_cap_releases mds%d\n", session->s_mds);
while (1) {
spin_lock(&session->s_cap_lock);
if (list_empty(&session->s_cap_releases_done))
break;
msg = list_first_entry(&session->s_cap_releases_done,
struct ceph_msg, list_head);
list_del_init(&msg->list_head);
spin_unlock(&session->s_cap_lock);
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);
}
spin_unlock(&session->s_cap_lock);
}
/*
* requests
*/
/*
* 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);
if (!req)
return ERR_PTR(-ENOMEM);
req->r_started = jiffies;
req->r_resend_mds = -1;
INIT_LIST_HEAD(&req->r_unsafe_dir_item);
req->r_fmode = -1;
kref_init(&req->r_kref);
INIT_LIST_HEAD(&req->r_wait);
init_completion(&req->r_completion);
init_completion(&req->r_safe_completion);
INIT_LIST_HEAD(&req->r_unsafe_item);
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 u64 __get_oldest_tid(struct ceph_mds_client *mdsc)
{
struct ceph_mds_request *req = __get_oldest_req(mdsc);
if (req)
return req->r_tid;
return 0;
}
/*
* 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;
if (dentry == NULL)
return ERR_PTR(-EINVAL);
retry:
len = 0;
for (temp = dentry; !IS_ROOT(temp);) {
struct inode *inode = temp->d_inode;
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;
if (temp == NULL) {
pr_err("build_path_dentry corrupt dentry %p\n", dentry);
return ERR_PTR(-EINVAL);
}
}
if (len)
len--; /* no leading '/' */
path = kmalloc(len+1, GFP_NOFS);
if (path == NULL)
return ERR_PTR(-ENOMEM);
pos = len;
path[pos] = 0; /* trailing null */
for (temp = dentry; !IS_ROOT(temp) && pos != 0; ) {
struct inode *inode = temp->d_inode;
if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
dout("build_path_dentry path+%d: %p SNAPDIR\n",
pos, temp);
} else if (stop_on_nosnap && inode &&
ceph_snap(inode) == CEPH_NOSNAP) {
break;
} else {
pos -= temp->d_name.len;
if (pos < 0)
break;
strncpy(path + pos, temp->d_name.name,
temp->d_name.len);
dout("build_path_dentry path+%d: %p '%.*s'\n",
pos, temp, temp->d_name.len, path + pos);
}
if (pos)
path[--pos] = '/';
temp = temp->d_parent;
if (temp == NULL) {
pr_err("build_path_dentry corrupt dentry\n");
kfree(path);
return ERR_PTR(-EINVAL);
}
}
if (pos != 0) {
pr_err("build_path_dentry 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(temp->d_inode);
*plen = len;
dout("build_path_dentry on %p %d built %llx '%.*s'\n",
dentry, atomic_read(&dentry->d_count), *base, len, path);
return path;
}
static int build_dentry_path(struct dentry *dentry,
const char **ppath, int *ppathlen, u64 *pino,
int *pfreepath)
{
char *path;
if (ceph_snap(dentry->d_parent->d_inode) == CEPH_NOSNAP) {
*pino = ceph_ino(dentry->d_parent->d_inode);
*ppath = dentry->d_name.name;
*ppathlen = dentry->d_name.len;
return 0;
}
path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
if (IS_ERR(path))
return PTR_ERR(path);
*ppath = path;
*pfreepath = 1;
return 0;
}
static int build_inode_path(struct inode *inode,
const char **ppath, int *ppathlen, u64 *pino,
int *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 = 1;
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,
const char *rpath, u64 rino,
const char **ppath, int *pathlen,
u64 *ino, int *freepath)
{
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, ppath, pathlen, ino, freepath);
dout(" dentry %p %llx/%.*s\n", rdentry, *ino, *pathlen,
*ppath);
} else if (rpath) {
*ino = rino;
*ppath = rpath;
*pathlen = strlen(rpath);
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)
{
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;
int freepath1 = 0, freepath2 = 0;
int len;
u16 releases;
void *p, *end;
int ret;
ret = set_request_path_attr(req->r_inode, req->r_dentry,
req->r_path1, req->r_ino1.ino,
&path1, &pathlen1, &ino1, &freepath1);
if (ret < 0) {
msg = ERR_PTR(ret);
goto out;
}
ret = set_request_path_attr(NULL, req->r_old_dentry,
req->r_path2, req->r_ino2.ino,
&path2, &pathlen2, &ino2, &freepath2);
if (ret < 0) {
msg = ERR_PTR(ret);
goto out_free1;
}
len = sizeof(*head) +
pathlen1 + pathlen2 + 2*(1 + sizeof(u32) + sizeof(u64));
/* 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_new(CEPH_MSG_CLIENT_REQUEST, len, 0, 0, NULL);
if (IS_ERR(msg))
goto out_free2;
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(current_fsuid());
head->caller_gid = cpu_to_le32(current_fsgid());
head->args = req->r_args;
ceph_encode_filepath(&p, end, ino1, path1);
ceph_encode_filepath(&p, end, ino2, path2);
/* cap releases */
releases = 0;
if (req->r_inode_drop)
releases += ceph_encode_inode_release(&p,
req->r_inode ? req->r_inode : req->r_dentry->d_inode,
mds, req->r_inode_drop, req->r_inode_unless, 0);
if (req->r_dentry_drop)
releases += ceph_encode_dentry_release(&p, req->r_dentry,
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,
mds, req->r_old_dentry_drop, req->r_old_dentry_unless);
if (req->r_old_inode_drop)
releases += ceph_encode_inode_release(&p,
req->r_old_dentry->d_inode,
mds, req->r_old_inode_drop, req->r_old_inode_unless, 0);
head->num_releases = cpu_to_le16(releases);
BUG_ON(p > end);
msg->front.iov_len = p - msg->front.iov_base;
msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
msg->pages = req->r_pages;
msg->nr_pages = req->r_num_pages;
msg->hdr.data_len = cpu_to_le32(req->r_data_len);
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(&req->r_completion);
}
/*
* called under mdsc->mutex
*/
static int __prepare_send_request(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req,
int mds)
{
struct ceph_mds_request_head *rhead;
struct ceph_msg *msg;
int flags = 0;
req->r_mds = mds;
req->r_attempts++;
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 (req->r_request) {
ceph_msg_put(req->r_request);
req->r_request = NULL;
}
msg = create_request_message(mdsc, req, mds);
if (IS_ERR(msg)) {
req->r_reply = ERR_PTR(PTR_ERR(msg));
complete_request(mdsc, req);
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 (req->r_got_unsafe)
flags |= CEPH_MDS_FLAG_REPLAY;
if (req->r_locked_dir)
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;
dout(" r_locked_dir = %p\n", req->r_locked_dir);
if (req->r_target_inode && req->r_got_unsafe)
rhead->ino = cpu_to_le64(ceph_ino(req->r_target_inode));
else
rhead->ino = 0;
return 0;
}
/*
* send request, or put it on the appropriate wait list.
*/
static int __do_request(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req)
{
struct ceph_mds_session *session = NULL;
int mds = -1;
int err = -EAGAIN;
if (req->r_reply)
goto out;
if (req->r_timeout &&
time_after_eq(jiffies, req->r_started + req->r_timeout)) {
dout("do_request timed out\n");
err = -EIO;
goto finish;
}
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);
goto out;
}
/* 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;
}
}
dout("do_request mds%d session %p state %s\n", mds, session,
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_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_session = get_session(session);
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);
if (!err) {
ceph_msg_get(req->r_request);
ceph_con_send(&session->s_con, req->r_request);
}
out_session:
ceph_put_mds_session(session);
out:
return err;
finish:
req->r_reply = ERR_PTR(err);
complete_request(mdsc, req);
goto out;
}
/*
* called under mdsc->mutex
*/
static void __wake_requests(struct ceph_mds_client *mdsc,
struct list_head *head)
{
struct ceph_mds_request *req, *nreq;
list_for_each_entry_safe(req, nreq, head, r_wait) {
list_del_init(&req->r_wait);
__do_request(mdsc, req);
}
}
/*
* Wake up threads with requests pending for @mds, so that they can
* resubmit their requests to a possibly different mds. If @all is set,
* wake up if their requests has been forwarded to @mds, too.
*/
static void kick_requests(struct ceph_mds_client *mdsc, int mds, int all)
{
struct ceph_mds_request *req;
struct rb_node *p;
dout("kick_requests mds%d\n", mds);
for (p = rb_first(&mdsc->request_tree); p; p = rb_next(p)) {
req = rb_entry(p, struct ceph_mds_request, r_node);
if (req->r_got_unsafe)
continue;
if (req->r_session &&
req->r_session->s_mds == mds) {
dout(" kicking tid %llu\n", req->r_tid);
put_request_session(req);
__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_locked_dir, r_old_dentry */
if (req->r_inode)
ceph_get_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
if (req->r_locked_dir)
ceph_get_cap_refs(ceph_inode(req->r_locked_dir), CEPH_CAP_PIN);
if (req->r_old_dentry)
ceph_get_cap_refs(
ceph_inode(req->r_old_dentry->d_parent->d_inode),
CEPH_CAP_PIN);
/* issue */
mutex_lock(&mdsc->mutex);
__register_request(mdsc, req, dir);
__do_request(mdsc, req);
/* wait */
if (!req->r_reply) {
mutex_unlock(&mdsc->mutex);
if (req->r_timeout) {
err = (long)wait_for_completion_interruptible_timeout(
&req->r_completion, req->r_timeout);
if (err == 0)
req->r_reply = ERR_PTR(-EIO);
else if (err < 0)
req->r_reply = ERR_PTR(err);
} else {
err = wait_for_completion_interruptible(
&req->r_completion);
if (err)
req->r_reply = ERR_PTR(err);
}
mutex_lock(&mdsc->mutex);
}
if (IS_ERR(req->r_reply)) {
err = PTR_ERR(req->r_reply);
req->r_reply = NULL;
if (err == -ERESTARTSYS) {
/* aborted */
req->r_aborted = true;
if (req->r_locked_dir &&
(req->r_op & CEPH_MDS_OP_WRITE)) {
struct ceph_inode_info *ci =
ceph_inode(req->r_locked_dir);
dout("aborted, clearing I_COMPLETE on %p\n",
req->r_locked_dir);
spin_lock(&req->r_locked_dir->i_lock);
ci->i_ceph_flags &= ~CEPH_I_COMPLETE;
ci->i_release_count++;
spin_unlock(&req->r_locked_dir->i_lock);
}
} else {
/* clean up this request */
__unregister_request(mdsc, req);
if (!list_empty(&req->r_unsafe_item))
list_del_init(&req->r_unsafe_item);
complete(&req->r_safe_completion);
}
} else if (req->r_err) {
err = req->r_err;
} else {
err = le32_to_cpu(req->r_reply_info.head->result);
}
mutex_unlock(&mdsc->mutex);
dout("do_request %p done, result %d\n", req, err);
return err;
}
/*
* 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 */
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_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 ((req->r_got_unsafe && !head->safe) ||
(req->r_got_safe && head->safe)) {
pr_warning("got a dup %s reply on %llu from mds%d\n",
head->safe ? "safe" : "unsafe", tid, mds);
mutex_unlock(&mdsc->mutex);
goto out;
}
result = le32_to_cpu(head->result);
/*
* Tolerate 2 consecutive ESTALEs from the same mds.
* FIXME: we should be looking at the cap migrate_seq.
*/
if (result == -ESTALE) {
req->r_direct_mode = USE_AUTH_MDS;
req->r_num_stale++;
if (req->r_num_stale <= 2) {
__do_request(mdsc, req);
mutex_unlock(&mdsc->mutex);
goto out;
}
} else {
req->r_num_stale = 0;
}
if (head->safe) {
req->r_got_safe = true;
__unregister_request(mdsc, req);
complete(&req->r_safe_completion);
if (req->r_got_unsafe) {
/*
* 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);
list_del_init(&req->r_unsafe_item);
/* last unsafe request during umount? */
if (mdsc->stopping && !__get_oldest_req(mdsc))
complete(&mdsc->safe_umount_waiters);
mutex_unlock(&mdsc->mutex);
goto out;
}
}
BUG_ON(req->r_reply);
if (!head->safe) {
req->r_got_unsafe = true;
list_add_tail(&req->r_unsafe_item, &req->r_session->s_unsafe);
}
dout("handle_reply tid %lld result %d\n", tid, result);
rinfo = &req->r_reply_info;
err = parse_reply_info(msg, rinfo);
mutex_unlock(&mdsc->mutex);
mutex_lock(&session->s_mutex);
if (err < 0) {
pr_err("mdsc_handle_reply got corrupt reply mds%d\n", mds);
ceph_msg_dump(msg);
goto out_err;
}
/* snap trace */
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);
downgrade_write(&mdsc->snap_rwsem);
} else {
down_read(&mdsc->snap_rwsem);
}
/* insert trace into our cache */
err = ceph_fill_trace(mdsc->client->sb, req, req->r_session);
if (err == 0) {
if (result == 0 && rinfo->dir_nr)
ceph_readdir_prepopulate(req, req->r_session);
ceph_unreserve_caps(&req->r_caps_reservation);
}
up_read(&mdsc->snap_rwsem);
out_err:
if (err) {
req->r_err = err;
} else {
req->r_reply = msg;
ceph_msg_get(msg);
}
add_cap_releases(mdsc, req->r_session, -1);
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 = le64_to_cpu(msg->hdr.tid);
u32 next_mds;
u32 fwd_seq;
int err = -EINVAL;
void *p = msg->front.iov_base;
void *end = p + msg->front.iov_len;
ceph_decode_need(&p, end, 2*sizeof(u32), bad);
next_mds = ceph_decode_32(&p);
fwd_seq = ceph_decode_32(&p);
mutex_lock(&mdsc->mutex);
req = __lookup_request(mdsc, tid);
if (!req) {
dout("forward %llu to mds%d - req dne\n", tid, next_mds);
goto out; /* dup reply? */
}
if (fwd_seq <= req->r_num_fwd) {
dout("forward %llu to mds%d - old seq %d <= %d\n",
tid, next_mds, req->r_num_fwd, fwd_seq);
} else {
/* resend. forward race not possible; mds would drop */
dout("forward %llu to mds%d (we resend)\n", tid, next_mds);
req->r_num_fwd = fwd_seq;
req->r_resend_mds = next_mds;
put_request_session(req);
__do_request(mdsc, req);
}
ceph_mdsc_put_request(req);
out:
mutex_unlock(&mdsc->mutex);
return;
bad:
pr_err("mdsc_handle_forward decode error err=%d\n", err);
}
/*
* handle a mds session control message
*/
static void handle_session(struct ceph_mds_session *session,
struct ceph_msg *msg)
{
struct ceph_mds_client *mdsc = session->s_mdsc;
u32 op;
u64 seq;
int mds = session->s_mds;
struct ceph_mds_session_head *h = msg->front.iov_base;
int wake = 0;
/* decode */
if (msg->front.iov_len != sizeof(*h))
goto bad;
op = le32_to_cpu(h->op);
seq = le64_to_cpu(h->seq);
mutex_lock(&mdsc->mutex);
if (op == CEPH_SESSION_CLOSE)
__unregister_session(mdsc, session);
/* FIXME: this ttl calculation is generous */
session->s_ttl = jiffies + HZ*mdsc->mdsmap->m_session_autoclose;
mutex_unlock(&mdsc->mutex);
mutex_lock(&session->s_mutex);
dout("handle_session mds%d %s %p state %s seq %llu\n",
mds, ceph_session_op_name(op), session,
session_state_name(session->s_state), seq);
if (session->s_state == CEPH_MDS_SESSION_HUNG) {
session->s_state = CEPH_MDS_SESSION_OPEN;
pr_info("mds%d came back\n", session->s_mds);
}
switch (op) {
case CEPH_SESSION_OPEN:
session->s_state = CEPH_MDS_SESSION_OPEN;
renewed_caps(mdsc, session, 0);
wake = 1;
if (mdsc->stopping)
__close_session(mdsc, session);
break;
case CEPH_SESSION_RENEWCAPS:
if (session->s_renew_seq == seq)
renewed_caps(mdsc, session, 1);
break;
case CEPH_SESSION_CLOSE:
remove_session_caps(session);
wake = 1; /* for good measure */
complete(&mdsc->session_close_waiters);
kick_requests(mdsc, mds, 0); /* cur only */
break;
case CEPH_SESSION_STALE:
pr_info("mds%d caps went stale, renewing\n",
session->s_mds);
spin_lock(&session->s_cap_lock);
session->s_cap_gen++;
session->s_cap_ttl = 0;
spin_unlock(&session->s_cap_lock);
send_renew_caps(mdsc, session);
break;
case CEPH_SESSION_RECALL_STATE:
trim_caps(mdsc, session, le32_to_cpu(h->max_caps));
break;
default:
pr_err("mdsc_handle_session bad op %d mds%d\n", op, mds);
WARN_ON(1);
}
mutex_unlock(&session->s_mutex);
if (wake) {
mutex_lock(&mdsc->mutex);
__wake_requests(mdsc, &session->s_waiting);
mutex_unlock(&mdsc->mutex);
}
return;
bad:
pr_err("mdsc_handle_session corrupt message mds%d len %d\n", mds,
(int)msg->front.iov_len);
ceph_msg_dump(msg);
return;
}
/*
* called under session->mutex.
*/
static void replay_unsafe_requests(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session)
{
struct ceph_mds_request *req, *nreq;
int err;
dout("replay_unsafe_requests mds%d\n", session->s_mds);
mutex_lock(&mdsc->mutex);
list_for_each_entry_safe(req, nreq, &session->s_unsafe, r_unsafe_item) {
err = __prepare_send_request(mdsc, req, session->s_mds);
if (!err) {
ceph_msg_get(req->r_request);
ceph_con_send(&session->s_con, req->r_request);
}
}
mutex_unlock(&mdsc->mutex);
}
/*
* Encode information about a cap for a reconnect with the MDS.
*/
static int encode_caps_cb(struct inode *inode, struct ceph_cap *cap,
void *arg)
{
struct ceph_mds_cap_reconnect rec;
struct ceph_inode_info *ci;
struct ceph_pagelist *pagelist = arg;
char *path;
int pathlen, err;
u64 pathbase;
struct dentry *dentry;
ci = cap->ci;
dout(" adding %p ino %llx.%llx cap %p %lld %s\n",
inode, ceph_vinop(inode), cap, cap->cap_id,
ceph_cap_string(cap->issued));
err = ceph_pagelist_encode_64(pagelist, ceph_ino(inode));
if (err)
return err;
dentry = d_find_alias(inode);
if (dentry) {
path = ceph_mdsc_build_path(dentry, &pathlen, &pathbase, 0);
if (IS_ERR(path)) {
err = PTR_ERR(path);
BUG_ON(err);
}
} else {
path = NULL;
pathlen = 0;
}
err = ceph_pagelist_encode_string(pagelist, path, pathlen);
if (err)
goto out;
spin_lock(&inode->i_lock);
cap->seq = 0; /* reset cap seq */
cap->issue_seq = 0; /* and issue_seq */
rec.cap_id = cpu_to_le64(cap->cap_id);
rec.pathbase = cpu_to_le64(pathbase);
rec.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
rec.issued = cpu_to_le32(cap->issued);
rec.size = cpu_to_le64(inode->i_size);
ceph_encode_timespec(&rec.mtime, &inode->i_mtime);
ceph_encode_timespec(&rec.atime, &inode->i_atime);
rec.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
spin_unlock(&inode->i_lock);
err = ceph_pagelist_append(pagelist, &rec, sizeof(rec));
out:
kfree(path);
dput(dentry);
return err;
}
/*
* If an MDS fails and recovers, clients need to reconnect in order to
* reestablish shared state. This includes all caps issued through
* this session _and_ the snap_realm hierarchy. Because it's not
* clear which snap realms the mds cares about, we send everything we
* know about.. that ensures we'll then get any new info the
* recovering MDS might have.
*
* This is a relatively heavyweight operation, but it's rare.
*
* called with mdsc->mutex held.
*/
static void send_mds_reconnect(struct ceph_mds_client *mdsc, int mds)
{
struct ceph_mds_session *session = NULL;
struct ceph_msg *reply;
struct rb_node *p;
int err = -ENOMEM;
struct ceph_pagelist *pagelist;
pr_info("reconnect to recovering mds%d\n", mds);
pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
if (!pagelist)
goto fail_nopagelist;
ceph_pagelist_init(pagelist);
reply = ceph_msg_new(CEPH_MSG_CLIENT_RECONNECT, 0, 0, 0, NULL);
if (IS_ERR(reply)) {
err = PTR_ERR(reply);
goto fail_nomsg;
}
/* find session */
session = __ceph_lookup_mds_session(mdsc, mds);
mutex_unlock(&mdsc->mutex); /* drop lock for duration */
if (session) {
mutex_lock(&session->s_mutex);
session->s_state = CEPH_MDS_SESSION_RECONNECTING;
session->s_seq = 0;
ceph_con_open(&session->s_con,
ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
/* replay unsafe requests */
replay_unsafe_requests(mdsc, session);
} else {
dout("no session for mds%d, will send short reconnect\n",
mds);
}
down_read(&mdsc->snap_rwsem);
if (!session)
goto send;
dout("session %p state %s\n", session,
session_state_name(session->s_state));
/* traverse this session's caps */
err = ceph_pagelist_encode_32(pagelist, session->s_nr_caps);
if (err)
goto fail;
err = iterate_session_caps(session, encode_caps_cb, pagelist);
if (err < 0)
goto fail;
/*
* snaprealms. we provide mds with the ino, seq (version), and
* parent for all of our realms. If the mds has any newer info,
* it will tell us.
*/
for (p = rb_first(&mdsc->snap_realms); p; p = rb_next(p)) {
struct ceph_snap_realm *realm =
rb_entry(p, struct ceph_snap_realm, node);
struct ceph_mds_snaprealm_reconnect sr_rec;
dout(" adding snap realm %llx seq %lld parent %llx\n",
realm->ino, realm->seq, realm->parent_ino);
sr_rec.ino = cpu_to_le64(realm->ino);
sr_rec.seq = cpu_to_le64(realm->seq);
sr_rec.parent = cpu_to_le64(realm->parent_ino);
err = ceph_pagelist_append(pagelist, &sr_rec, sizeof(sr_rec));
if (err)
goto fail;
}
send:
reply->pagelist = pagelist;
reply->hdr.data_len = cpu_to_le32(pagelist->length);
reply->nr_pages = calc_pages_for(0, pagelist->length);
ceph_con_send(&session->s_con, reply);
session->s_state = CEPH_MDS_SESSION_OPEN;
mutex_unlock(&session->s_mutex);
mutex_lock(&mdsc->mutex);
__wake_requests(mdsc, &session->s_waiting);
mutex_unlock(&mdsc->mutex);
ceph_put_mds_session(session);
up_read(&mdsc->snap_rwsem);
mutex_lock(&mdsc->mutex);
return;
fail:
ceph_msg_put(reply);
up_read(&mdsc->snap_rwsem);
mutex_unlock(&session->s_mutex);
ceph_put_mds_session(session);
fail_nomsg:
ceph_pagelist_release(pagelist);
kfree(pagelist);
fail_nopagelist:
pr_err("error %d preparing reconnect for mds%d\n", err, mds);
mutex_lock(&mdsc->mutex);
return;
}
/*
* compare old and new mdsmaps, kicking requests
* and closing out old connections as necessary
*
* called under mdsc->mutex.
*/
static void check_new_map(struct ceph_mds_client *mdsc,
struct ceph_mdsmap *newmap,
struct ceph_mdsmap *oldmap)
{
int i;
int oldstate, newstate;
struct ceph_mds_session *s;
dout("check_new_map new %u old %u\n",
newmap->m_epoch, oldmap->m_epoch);
for (i = 0; i < oldmap->m_max_mds && i < mdsc->max_sessions; i++) {
if (mdsc->sessions[i] == NULL)
continue;
s = mdsc->sessions[i];
oldstate = ceph_mdsmap_get_state(oldmap, i);
newstate = ceph_mdsmap_get_state(newmap, i);
dout("check_new_map mds%d state %s -> %s (session %s)\n",
i, ceph_mds_state_name(oldstate),
ceph_mds_state_name(newstate),
session_state_name(s->s_state));
if (memcmp(ceph_mdsmap_get_addr(oldmap, i),
ceph_mdsmap_get_addr(newmap, i),
sizeof(struct ceph_entity_addr))) {
if (s->s_state == CEPH_MDS_SESSION_OPENING) {
/* the session never opened, just close it
* out now */
__wake_requests(mdsc, &s->s_waiting);
__unregister_session(mdsc, s);
} else {
/* just close it */
mutex_unlock(&mdsc->mutex);
mutex_lock(&s->s_mutex);
mutex_lock(&mdsc->mutex);
ceph_con_close(&s->s_con);
mutex_unlock(&s->s_mutex);
s->s_state = CEPH_MDS_SESSION_RESTARTING;
}
/* kick any requests waiting on the recovering mds */
kick_requests(mdsc, i, 1);
} else if (oldstate == newstate) {
continue; /* nothing new with this mds */
}
/*
* send reconnect?
*/
if (s->s_state == CEPH_MDS_SESSION_RESTARTING &&
newstate >= CEPH_MDS_STATE_RECONNECT)
send_mds_reconnect(mdsc, i);
/*
* kick requests on any mds that has gone active.
*
* kick requests on cur or forwarder: we may have sent
* the request to mds1, mds1 told us it forwarded it
* to mds2, but then we learn mds1 failed and can't be
* sure it successfully forwarded our request before
* it died.
*/
if (oldstate < CEPH_MDS_STATE_ACTIVE &&
newstate >= CEPH_MDS_STATE_ACTIVE) {
pr_info("mds%d reconnect completed\n", s->s_mds);
kick_requests(mdsc, i, 1);
ceph_kick_flushing_caps(mdsc, s);
wake_up_session_caps(s, 1);
}
}
}
/*
* leases
*/
/*
* caller must hold session s_mutex, dentry->d_lock
*/
void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry)
{
struct ceph_dentry_info *di = ceph_dentry(dentry);
ceph_put_mds_session(di->lease_session);
di->lease_session = NULL;
}
static void handle_lease(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session,
struct ceph_msg *msg)
{
struct super_block *sb = mdsc->client->sb;
struct inode *inode;
struct ceph_inode_info *ci;
struct dentry *parent, *dentry;
struct ceph_dentry_info *di;
int mds = session->s_mds;
struct ceph_mds_lease *h = msg->front.iov_base;
struct ceph_vino vino;
int mask;
struct qstr dname;
int release = 0;
dout("handle_lease from mds%d\n", mds);
/* decode */
if (msg->front.iov_len < sizeof(*h) + sizeof(u32))
goto bad;
vino.ino = le64_to_cpu(h->ino);
vino.snap = CEPH_NOSNAP;
mask = le16_to_cpu(h->mask);
dname.name = (void *)h + sizeof(*h) + sizeof(u32);
dname.len = msg->front.iov_len - sizeof(*h) - sizeof(u32);
if (dname.len != get_unaligned_le32(h+1))
goto bad;
mutex_lock(&session->s_mutex);
session->s_seq++;
/* lookup inode */
inode = ceph_find_inode(sb, vino);
dout("handle_lease '%s', mask %d, ino %llx %p\n",
ceph_lease_op_name(h->action), mask, vino.ino, inode);
if (inode == NULL) {
dout("handle_lease no inode %llx\n", vino.ino);
goto release;
}
ci = ceph_inode(inode);
/* dentry */
parent = d_find_alias(inode);
if (!parent) {
dout("no parent dentry on inode %p\n", inode);
WARN_ON(1);
goto release; /* hrm... */
}
dname.hash = full_name_hash(dname.name, dname.len);
dentry = d_lookup(parent, &dname);
dput(parent);
if (!dentry)
goto release;
spin_lock(&dentry->d_lock);
di = ceph_dentry(dentry);
switch (h->action) {
case CEPH_MDS_LEASE_REVOKE:
if (di && di->lease_session == session) {
h->seq = cpu_to_le32(di->lease_seq);
__ceph_mdsc_drop_dentry_lease(dentry);
}
release = 1;
break;
case CEPH_MDS_LEASE_RENEW:
if (di && di->lease_session == session &&
di->lease_gen == session->s_cap_gen &&
di->lease_renew_from &&
di->lease_renew_after == 0) {
unsigned long duration =
le32_to_cpu(h->duration_ms) * HZ / 1000;
di->lease_seq = le32_to_cpu(h->seq);
dentry->d_time = di->lease_renew_from + duration;
di->lease_renew_after = di->lease_renew_from +
(duration >> 1);
di->lease_renew_from = 0;
}
break;
}
spin_unlock(&dentry->d_lock);
dput(dentry);
if (!release)
goto out;
release:
/* let's just reuse the same message */
h->action = CEPH_MDS_LEASE_REVOKE_ACK;
ceph_msg_get(msg);
ceph_con_send(&session->s_con, msg);
out:
iput(inode);
mutex_unlock(&session->s_mutex);
return;
bad:
pr_err("corrupt lease message\n");
ceph_msg_dump(msg);
}
void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
struct inode *inode,
struct dentry *dentry, char action,
u32 seq)
{
struct ceph_msg *msg;
struct ceph_mds_lease *lease;
int len = sizeof(*lease) + sizeof(u32);
int dnamelen = 0;
dout("lease_send_msg inode %p dentry %p %s to mds%d\n",
inode, dentry, ceph_lease_op_name(action), session->s_mds);
dnamelen = dentry->d_name.len;
len += dnamelen;
msg = ceph_msg_new(CEPH_MSG_CLIENT_LEASE, len, 0, 0, NULL);
if (IS_ERR(msg))
return;
lease = msg->front.iov_base;
lease->action = action;
lease->mask = cpu_to_le16(CEPH_LOCK_DN);
lease->ino = cpu_to_le64(ceph_vino(inode).ino);
lease->first = lease->last = cpu_to_le64(ceph_vino(inode).snap);
lease->seq = cpu_to_le32(seq);
put_unaligned_le32(dnamelen, lease + 1);
memcpy((void *)(lease + 1) + 4, dentry->d_name.name, dnamelen);
/*
* if this is a preemptive lease RELEASE, no need to
* flush request stream, since the actual request will
* soon follow.
*/
msg->more_to_follow = (action == CEPH_MDS_LEASE_RELEASE);
ceph_con_send(&session->s_con, msg);
}
/*
* Preemptively release a lease we expect to invalidate anyway.
* Pass @inode always, @dentry is optional.
*/
void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc, struct inode *inode,
struct dentry *dentry, int mask)
{
struct ceph_dentry_info *di;
struct ceph_mds_session *session;
u32 seq;
BUG_ON(inode == NULL);
BUG_ON(dentry == NULL);
BUG_ON(mask != CEPH_LOCK_DN);
/* is dentry lease valid? */
spin_lock(&dentry->d_lock);
di = ceph_dentry(dentry);
if (!di || !di->lease_session ||
di->lease_session->s_mds < 0 ||
di->lease_gen != di->lease_session->s_cap_gen ||
!time_before(jiffies, dentry->d_time)) {
dout("lease_release inode %p dentry %p -- "
"no lease on %d\n",
inode, dentry, mask);
spin_unlock(&dentry->d_lock);
return;
}
/* we do have a lease on this dentry; note mds and seq */
session = ceph_get_mds_session(di->lease_session);
seq = di->lease_seq;
__ceph_mdsc_drop_dentry_lease(dentry);
spin_unlock(&dentry->d_lock);
dout("lease_release inode %p dentry %p mask %d to mds%d\n",
inode, dentry, mask, session->s_mds);
ceph_mdsc_lease_send_msg(session, inode, dentry,
CEPH_MDS_LEASE_RELEASE, seq);
ceph_put_mds_session(session);
}
/*
* drop all leases (and dentry refs) in preparation for umount
*/
static void drop_leases(struct ceph_mds_client *mdsc)
{
int i;
dout("drop_leases\n");
mutex_lock(&mdsc->mutex);
for (i = 0; i < mdsc->max_sessions; i++) {
struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
if (!s)
continue;
mutex_unlock(&mdsc->mutex);
mutex_lock(&s->s_mutex);
mutex_unlock(&s->s_mutex);
ceph_put_mds_session(s);
mutex_lock(&mdsc->mutex);
}
mutex_unlock(&mdsc->mutex);
}
/*
* delayed work -- periodically trim expired leases, renew caps with mds
*/
static void schedule_delayed(struct ceph_mds_client *mdsc)
{
int delay = 5;
unsigned hz = round_jiffies_relative(HZ * delay);
schedule_delayed_work(&mdsc->delayed_work, hz);
}
static void delayed_work(struct work_struct *work)
{
int i;
struct ceph_mds_client *mdsc =
container_of(work, struct ceph_mds_client, delayed_work.work);
int renew_interval;
int renew_caps;
dout("mdsc delayed_work\n");
ceph_check_delayed_caps(mdsc);
mutex_lock(&mdsc->mutex);
renew_interval = mdsc->mdsmap->m_session_timeout >> 2;
renew_caps = time_after_eq(jiffies, HZ*renew_interval +
mdsc->last_renew_caps);
if (renew_caps)
mdsc->last_renew_caps = jiffies;
for (i = 0; i < mdsc->max_sessions; i++) {
struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
if (s == NULL)
continue;
if (s->s_state == CEPH_MDS_SESSION_CLOSING) {
dout("resending session close request for mds%d\n",
s->s_mds);
request_close_session(mdsc, s);
ceph_put_mds_session(s);
continue;
}
if (s->s_ttl && time_after(jiffies, s->s_ttl)) {
if (s->s_state == CEPH_MDS_SESSION_OPEN) {
s->s_state = CEPH_MDS_SESSION_HUNG;
pr_info("mds%d hung\n", s->s_mds);
}
}
if (s->s_state < CEPH_MDS_SESSION_OPEN) {
/* this mds is failed or recovering, just wait */
ceph_put_mds_session(s);
continue;
}
mutex_unlock(&mdsc->mutex);
mutex_lock(&s->s_mutex);
if (renew_caps)
send_renew_caps(mdsc, s);
else
ceph_con_keepalive(&s->s_con);
add_cap_releases(mdsc, s, -1);
send_cap_releases(mdsc, s);
mutex_unlock(&s->s_mutex);
ceph_put_mds_session(s);
mutex_lock(&mdsc->mutex);
}
mutex_unlock(&mdsc->mutex);
schedule_delayed(mdsc);
}
int ceph_mdsc_init(struct ceph_mds_client *mdsc, struct ceph_client *client)
{
mdsc->client = client;
mutex_init(&mdsc->mutex);
mdsc->mdsmap = kzalloc(sizeof(*mdsc->mdsmap), GFP_NOFS);
init_completion(&mdsc->safe_umount_waiters);
init_completion(&mdsc->session_close_waiters);
INIT_LIST_HEAD(&mdsc->waiting_for_map);
mdsc->sessions = NULL;
mdsc->max_sessions = 0;
mdsc->stopping = 0;
init_rwsem(&mdsc->snap_rwsem);
mdsc->snap_realms = RB_ROOT;
INIT_LIST_HEAD(&mdsc->snap_empty);
spin_lock_init(&mdsc->snap_empty_lock);
mdsc->last_tid = 0;
mdsc->request_tree = RB_ROOT;
INIT_DELAYED_WORK(&mdsc->delayed_work, delayed_work);
mdsc->last_renew_caps = jiffies;
INIT_LIST_HEAD(&mdsc->cap_delay_list);
spin_lock_init(&mdsc->cap_delay_lock);
INIT_LIST_HEAD(&mdsc->snap_flush_list);
spin_lock_init(&mdsc->snap_flush_lock);
mdsc->cap_flush_seq = 0;
INIT_LIST_HEAD(&mdsc->cap_dirty);
mdsc->num_cap_flushing = 0;
spin_lock_init(&mdsc->cap_dirty_lock);
init_waitqueue_head(&mdsc->cap_flushing_wq);
spin_lock_init(&mdsc->dentry_lru_lock);
INIT_LIST_HEAD(&mdsc->dentry_lru);
return 0;
}
/*
* Wait for safe replies on open mds requests. If we time out, drop
* all requests from the tree to avoid dangling dentry refs.
*/
static void wait_requests(struct ceph_mds_client *mdsc)
{
struct ceph_mds_request *req;
struct ceph_client *client = mdsc->client;
mutex_lock(&mdsc->mutex);
if (__get_oldest_req(mdsc)) {
mutex_unlock(&mdsc->mutex);
dout("wait_requests waiting for requests\n");
wait_for_completion_timeout(&mdsc->safe_umount_waiters,
client->mount_args->mount_timeout * HZ);
/* tear down remaining requests */
mutex_lock(&mdsc->mutex);
while ((req = __get_oldest_req(mdsc))) {
dout("wait_requests timed out on tid %llu\n",
req->r_tid);
__unregister_request(mdsc, req);
}
}
mutex_unlock(&mdsc->mutex);
dout("wait_requests done\n");
}
/*
* called before mount is ro, and before dentries are torn down.
* (hmm, does this still race with new lookups?)
*/
void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc)
{
dout("pre_umount\n");
mdsc->stopping = 1;
drop_leases(mdsc);
ceph_flush_dirty_caps(mdsc);
wait_requests(mdsc);
}
/*
* wait for all write mds requests to flush.
*/
static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid)
{
struct ceph_mds_request *req = NULL, *nextreq;
struct rb_node *n;
mutex_lock(&mdsc->mutex);
dout("wait_unsafe_requests want %lld\n", want_tid);
restart:
req = __get_oldest_req(mdsc);
while (req && req->r_tid <= want_tid) {
/* find next request */
n = rb_next(&req->r_node);
if (n)
nextreq = rb_entry(n, struct ceph_mds_request, r_node);
else
nextreq = NULL;
if ((req->r_op & CEPH_MDS_OP_WRITE)) {
/* write op */
ceph_mdsc_get_request(req);
if (nextreq)
ceph_mdsc_get_request(nextreq);
mutex_unlock(&mdsc->mutex);
dout("wait_unsafe_requests wait on %llu (want %llu)\n",
req->r_tid, want_tid);
wait_for_completion(&req->r_safe_completion);
mutex_lock(&mdsc->mutex);
ceph_mdsc_put_request(req);
if (!nextreq)
break; /* next dne before, so we're done! */
if (RB_EMPTY_NODE(&nextreq->r_node)) {
/* next request was removed from tree */
ceph_mdsc_put_request(nextreq);
goto restart;
}
ceph_mdsc_put_request(nextreq); /* won't go away */
}
req = nextreq;
}
mutex_unlock(&mdsc->mutex);
dout("wait_unsafe_requests done\n");
}
void ceph_mdsc_sync(struct ceph_mds_client *mdsc)
{
u64 want_tid, want_flush;
dout("sync\n");
mutex_lock(&mdsc->mutex);
want_tid = mdsc->last_tid;
want_flush = mdsc->cap_flush_seq;
mutex_unlock(&mdsc->mutex);
dout("sync want tid %lld flush_seq %lld\n", want_tid, want_flush);
ceph_flush_dirty_caps(mdsc);
wait_unsafe_requests(mdsc, want_tid);
wait_event(mdsc->cap_flushing_wq, check_cap_flush(mdsc, want_flush));
}
/*
* called after sb is ro.
*/
void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc)
{
struct ceph_mds_session *session;
int i;
int n;
struct ceph_client *client = mdsc->client;
unsigned long started, timeout = client->mount_args->mount_timeout * HZ;
dout("close_sessions\n");
mutex_lock(&mdsc->mutex);
/* close sessions */
started = jiffies;
while (time_before(jiffies, started + timeout)) {
dout("closing sessions\n");
n = 0;
for (i = 0; i < mdsc->max_sessions; i++) {
session = __ceph_lookup_mds_session(mdsc, i);
if (!session)
continue;
mutex_unlock(&mdsc->mutex);
mutex_lock(&session->s_mutex);
__close_session(mdsc, session);
mutex_unlock(&session->s_mutex);
ceph_put_mds_session(session);
mutex_lock(&mdsc->mutex);
n++;
}
if (n == 0)
break;
if (client->mount_state == CEPH_MOUNT_SHUTDOWN)
break;
dout("waiting for sessions to close\n");
mutex_unlock(&mdsc->mutex);
wait_for_completion_timeout(&mdsc->session_close_waiters,
timeout);
mutex_lock(&mdsc->mutex);
}
/* tear down remaining sessions */
for (i = 0; i < mdsc->max_sessions; i++) {
if (mdsc->sessions[i]) {
session = get_session(mdsc->sessions[i]);
__unregister_session(mdsc, session);
mutex_unlock(&mdsc->mutex);
mutex_lock(&session->s_mutex);
remove_session_caps(session);
mutex_unlock(&session->s_mutex);
ceph_put_mds_session(session);
mutex_lock(&mdsc->mutex);
}
}
WARN_ON(!list_empty(&mdsc->cap_delay_list));
mutex_unlock(&mdsc->mutex);
ceph_cleanup_empty_realms(mdsc);
cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
dout("stopped\n");
}
void ceph_mdsc_stop(struct ceph_mds_client *mdsc)
{
dout("stop\n");
cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
if (mdsc->mdsmap)
ceph_mdsmap_destroy(mdsc->mdsmap);
kfree(mdsc->sessions);
}
/*
* handle mds map update.
*/
void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
{
u32 epoch;
u32 maplen;
void *p = msg->front.iov_base;
void *end = p + msg->front.iov_len;
struct ceph_mdsmap *newmap, *oldmap;
struct ceph_fsid fsid;
int err = -EINVAL;
ceph_decode_need(&p, end, sizeof(fsid)+2*sizeof(u32), bad);
ceph_decode_copy(&p, &fsid, sizeof(fsid));
if (ceph_check_fsid(mdsc->client, &fsid) < 0)
return;
epoch = ceph_decode_32(&p);
maplen = ceph_decode_32(&p);
dout("handle_map epoch %u len %d\n", epoch, (int)maplen);
/* do we need it? */
ceph_monc_got_mdsmap(&mdsc->client->monc, epoch);
mutex_lock(&mdsc->mutex);
if (mdsc->mdsmap && epoch <= mdsc->mdsmap->m_epoch) {
dout("handle_map epoch %u <= our %u\n",
epoch, mdsc->mdsmap->m_epoch);
mutex_unlock(&mdsc->mutex);
return;
}
newmap = ceph_mdsmap_decode(&p, end);
if (IS_ERR(newmap)) {
err = PTR_ERR(newmap);
goto bad_unlock;
}
/* swap into place */
if (mdsc->mdsmap) {
oldmap = mdsc->mdsmap;
mdsc->mdsmap = newmap;
check_new_map(mdsc, newmap, oldmap);
ceph_mdsmap_destroy(oldmap);
} else {
mdsc->mdsmap = newmap; /* first mds map */
}
mdsc->client->sb->s_maxbytes = mdsc->mdsmap->m_max_file_size;
__wake_requests(mdsc, &mdsc->waiting_for_map);
mutex_unlock(&mdsc->mutex);
schedule_delayed(mdsc);
return;
bad_unlock:
mutex_unlock(&mdsc->mutex);
bad:
pr_err("error decoding mdsmap %d\n", err);
return;
}
static struct ceph_connection *con_get(struct ceph_connection *con)
{
struct ceph_mds_session *s = con->private;
if (get_session(s)) {
dout("mdsc con_get %p ok (%d)\n", s, atomic_read(&s->s_ref));
return con;
}
dout("mdsc con_get %p FAIL\n", s);
return NULL;
}
static void con_put(struct ceph_connection *con)
{
struct ceph_mds_session *s = con->private;
ceph_put_mds_session(s);
dout("mdsc con_put %p (%d)\n", s, atomic_read(&s->s_ref));
}
/*
* if the client is unresponsive for long enough, the mds will kill
* the session entirely.
*/
static void peer_reset(struct ceph_connection *con)
{
struct ceph_mds_session *s = con->private;
pr_err("mds%d gave us the boot. IMPLEMENT RECONNECT.\n",
s->s_mds);
}
static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
{
struct ceph_mds_session *s = con->private;
struct ceph_mds_client *mdsc = s->s_mdsc;
int type = le16_to_cpu(msg->hdr.type);
mutex_lock(&mdsc->mutex);
if (__verify_registered_session(mdsc, s) < 0) {
mutex_unlock(&mdsc->mutex);
goto out;
}
mutex_unlock(&mdsc->mutex);
switch (type) {
case CEPH_MSG_MDS_MAP:
ceph_mdsc_handle_map(mdsc, msg);
break;
case CEPH_MSG_CLIENT_SESSION:
handle_session(s, msg);
break;
case CEPH_MSG_CLIENT_REPLY:
handle_reply(s, msg);
break;
case CEPH_MSG_CLIENT_REQUEST_FORWARD:
handle_forward(mdsc, s, msg);
break;
case CEPH_MSG_CLIENT_CAPS:
ceph_handle_caps(s, msg);
break;
case CEPH_MSG_CLIENT_SNAP:
ceph_handle_snap(mdsc, s, msg);
break;
case CEPH_MSG_CLIENT_LEASE:
handle_lease(mdsc, s, msg);
break;
default:
pr_err("received unknown message type %d %s\n", type,
ceph_msg_type_name(type));
}
out:
ceph_msg_put(msg);
}
/*
* authentication
*/
static int get_authorizer(struct ceph_connection *con,
void **buf, int *len, int *proto,
void **reply_buf, int *reply_len, int force_new)
{
struct ceph_mds_session *s = con->private;
struct ceph_mds_client *mdsc = s->s_mdsc;
struct ceph_auth_client *ac = mdsc->client->monc.auth;
int ret = 0;
if (force_new && s->s_authorizer) {
ac->ops->destroy_authorizer(ac, s->s_authorizer);
s->s_authorizer = NULL;
}
if (s->s_authorizer == NULL) {
if (ac->ops->create_authorizer) {
ret = ac->ops->create_authorizer(
ac, CEPH_ENTITY_TYPE_MDS,
&s->s_authorizer,
&s->s_authorizer_buf,
&s->s_authorizer_buf_len,
&s->s_authorizer_reply_buf,
&s->s_authorizer_reply_buf_len);
if (ret)
return ret;
}
}
*proto = ac->protocol;
*buf = s->s_authorizer_buf;
*len = s->s_authorizer_buf_len;
*reply_buf = s->s_authorizer_reply_buf;
*reply_len = s->s_authorizer_reply_buf_len;
return 0;
}
static int verify_authorizer_reply(struct ceph_connection *con, int len)
{
struct ceph_mds_session *s = con->private;
struct ceph_mds_client *mdsc = s->s_mdsc;
struct ceph_auth_client *ac = mdsc->client->monc.auth;
return ac->ops->verify_authorizer_reply(ac, s->s_authorizer, len);
}
static int invalidate_authorizer(struct ceph_connection *con)
{
struct ceph_mds_session *s = con->private;
struct ceph_mds_client *mdsc = s->s_mdsc;
struct ceph_auth_client *ac = mdsc->client->monc.auth;
if (ac->ops->invalidate_authorizer)
ac->ops->invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS);
return ceph_monc_validate_auth(&mdsc->client->monc);
}
const static struct ceph_connection_operations mds_con_ops = {
.get = con_get,
.put = con_put,
.dispatch = dispatch,
.get_authorizer = get_authorizer,
.verify_authorizer_reply = verify_authorizer_reply,
.invalidate_authorizer = invalidate_authorizer,
.peer_reset = peer_reset,
};
/* eof */