diff options
Diffstat (limited to 'fs/ceph/mds_client.c')
| -rw-r--r-- | fs/ceph/mds_client.c | 3871 |
1 files changed, 3871 insertions, 0 deletions
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c new file mode 100644 index 000000000..84f37f34f --- /dev/null +++ b/fs/ceph/mds_client.c @@ -0,0 +1,3871 @@ +#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/utsname.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> + +/* + * 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 If + * the session times out and goes stale, our leases and capabilities + * are no longer valid.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 { + int nr_caps; + struct ceph_pagelist *pagelist; + bool flock; +}; + +static void __wake_requests(struct ceph_mds_client *mdsc, + struct list_head *head); + +static const 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, + u64 features) +{ + 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; + + if (features & CEPH_FEATURE_DIRLAYOUTHASH) + ceph_decode_copy_safe(p, end, &info->dir_layout, + sizeof(info->dir_layout), bad); + else + memset(&info->dir_layout, 0, sizeof(info->dir_layout)); + + 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 & 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; + + 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, + 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; + + 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, 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_dir(void **p, void *end, + struct ceph_mds_reply_info_parsed *info, + u64 features) +{ + 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; + + BUG_ON(!info->dir_in); + 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); + if ((unsigned long)(info->dir_dlease + num) > + (unsigned long)info->dir_in + info->dir_buf_size) { + pr_err("dir contents are larger than expected\n"); + WARN_ON(1); + goto bad; + } + + info->dir_nr = 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], features); + 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 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 & 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) +{ + if (info->head->op == CEPH_MDS_OP_GETFILELOCK) + return parse_reply_info_filelock(p, end, info, features); + else if (info->head->op == CEPH_MDS_OP_READDIR || + info->head->op == CEPH_MDS_OP_LSSNAP) + return parse_reply_info_dir(p, end, info, features); + else if (info->head->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_in) + return; + free_pages((unsigned long)info->dir_in, 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"; + 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_auth.authorizer) + ceph_auth_destroy_authorizer( + s->s_mdsc->fsc->client->monc.auth, + 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] == 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; + + if (mds >= mdsc->mdsmap->m_max_mds) + return ERR_PTR(-EINVAL); + + 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(&s->s_con, s, &mds_con_ops, &mdsc->fsc->client->msgr); + + spin_lock_init(&s->s_gen_ttl_lock); + s->s_cap_gen = 0; + 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; + 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_reconnect = 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(&mdsc->num_sessions); + atomic_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; + 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_locked_dir) + ceph_put_cap_refs(ceph_inode(req->r_locked_dir), 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); +} + +/* + * 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(mdsc, &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); + + req->r_uid = current_fsuid(); + req->r_gid = current_fsgid(); + + if (dir) { + struct ceph_inode_info *ci = ceph_inode(dir); + + ihold(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); + + iput(req->r_unsafe_dir); + req->r_unsafe_dir = NULL; + } + + complete_all(&req->r_safe_completion); + + 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 struct dentry *get_nonsnap_parent(struct dentry *dentry) +{ + /* + * we don't need to worry about protecting the d_parent access + * here because we never renaming inside the snapped namespace + * except to resplice to another snapdir, and either the old or new + * result is a valid result. + */ + while (!IS_ROOT(dentry) && ceph_snap(d_inode(dentry)) != CEPH_NOSNAP) + dentry = dentry->d_parent; + return dentry; +} + +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) { + /* ignore race with rename; old or new d_parent is okay */ + struct dentry *parent = req->r_dentry->d_parent; + struct inode *dir = d_inode(parent); + + if (dir->i_sb != mdsc->fsc->sb) { + /* not this fs! */ + inode = d_inode(req->r_dentry); + } else if (ceph_snap(dir) != CEPH_NOSNAP) { + /* direct snapped/virtual snapdir requests + * based on parent dir inode */ + struct dentry *dn = get_nonsnap_parent(parent); + inode = d_inode(dn); + 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 = dir; + hash = ceph_dentry_hash(dir, req->r_dentry); + 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, mds, + (int)r, frag.ndist); + if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >= + CEPH_MDS_STATE_ACTIVE) + 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); + if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >= + CEPH_MDS_STATE_ACTIVE) + return mds; + } + } + } + + 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); + 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); + 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; +} + +/* + * 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 metadata_bytes = 0; + int metadata_key_count = 0; + struct ceph_options *opt = mdsc->fsc->client->options; + void *p; + + const char* metadata[][2] = { + {"hostname", utsname()->nodename}, + {"kernel_version", utsname()->release}, + {"entity_id", opt->name ? opt->name : ""}, + {NULL, NULL} + }; + + /* Calculate serialized length of metadata */ + metadata_bytes = 4; /* map length */ + for (i = 0; metadata[i][0] != NULL; ++i) { + metadata_bytes += 8 + strlen(metadata[i][0]) + + strlen(metadata[i][1]); + metadata_key_count++; + } + + /* Allocate the message */ + msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h) + metadata_bytes, + 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(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(2); + msg->hdr.compat_version = cpu_to_le16(1); + + /* The write pointer, following the session_head structure */ + p = msg->front.iov_base + 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] != NULL; ++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; + } + + 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_max_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 + */ + +/* + * 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); +} + +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); + list_del_init(&req->r_unsafe_item); + pr_info(" 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 == 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); + + 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_inode_info *ci = ceph_inode(inode); + int drop = 0; + + dout("removing cap %p, ci is %p, inode is %p\n", + cap, ci, &ci->vfs_inode); + spin_lock(&ci->i_ceph_lock); + __ceph_remove_cap(cap, false); + if (!ci->i_auth_cap) { + struct ceph_mds_client *mdsc = + ceph_sb_to_client(inode->i_sb)->mdsc; + + spin_lock(&mdsc->cap_dirty_lock); + if (!list_empty(&ci->i_dirty_item)) { + pr_info(" 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 = 1; + } + if (!list_empty(&ci->i_flushing_item)) { + pr_info(" 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 = 1; + } + spin_unlock(&mdsc->cap_dirty_lock); + } + spin_unlock(&ci->i_ceph_lock); + while (drop--) + iput(inode); + 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); + + spin_lock(&session->s_cap_lock); + if (session->s_nr_caps > 0) { + struct super_block *sb = session->s_mdsc->fsc->sb; + 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); + } + } + spin_unlock(&session->s_cap_lock); + + BUG_ON(session->s_nr_caps > 0); + BUG_ON(!list_empty(&session->s_cap_flushing)); + 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_all(&ci->i_cap_wq); + if (arg) { + spin_lock(&ci->i_ceph_lock); + ci->i_wanted_max_size = 0; + ci->i_requested_max_size = 0; + spin_unlock(&ci->i_ceph_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 (!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, 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; + + 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 0; +} + +/* + * 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, 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) + goto out; + if ((used | wanted) & CEPH_CAP_ANY_WR) + goto out; + } + if ((used | wanted) & ~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, true); + } else { + /* try to drop referring dentries */ + spin_unlock(&ci->i_ceph_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(&ci->i_ceph_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; + } + + ceph_add_cap_releases(mdsc, session); + ceph_send_cap_releases(mdsc, session); + 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. + */ +int ceph_add_cap_releases(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session) +{ + struct ceph_msg *msg, *partial = NULL; + struct ceph_mds_cap_release *head; + int err = -ENOMEM; + int extra = mdsc->fsc->mount_options->cap_release_safety; + int num; + + dout("add_cap_releases %p mds%d extra %d\n", session, session->s_mds, + extra); + + 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; + num = le32_to_cpu(head->num); + if (num) { + dout(" partial %p with (%d/%d)\n", msg, num, + (int)CEPH_CAPS_PER_RELEASE); + extra += CEPH_CAPS_PER_RELEASE - num; + partial = msg; + } + } + 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, + GFP_NOFS, false); + 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 (partial) { + head = partial->front.iov_base; + num = le32_to_cpu(head->num); + dout(" queueing partial %p with %d/%d\n", partial, num, + (int)CEPH_CAPS_PER_RELEASE); + list_move_tail(&partial->list_head, + &session->s_cap_releases_done); + session->s_num_cap_releases -= CEPH_CAPS_PER_RELEASE - num; + } + err = 0; + spin_unlock(&session->s_cap_lock); +out_unlocked: + return err; +} + +static int check_cap_flush(struct inode *inode, u64 want_flush_seq) +{ + struct ceph_inode_info *ci = ceph_inode(inode); + int ret; + spin_lock(&ci->i_ceph_lock); + if (ci->i_flushing_caps) + ret = ci->i_cap_flush_seq >= want_flush_seq; + else + ret = 1; + spin_unlock(&ci->i_ceph_lock); + return ret; +} + +/* + * flush all dirty inode data to disk. + * + * returns true if we've flushed through want_flush_seq + */ +static void wait_caps_flush(struct ceph_mds_client *mdsc, u64 want_flush_seq) +{ + int mds; + + dout("check_cap_flush want %lld\n", want_flush_seq); + mutex_lock(&mdsc->mutex); + for (mds = 0; mds < mdsc->max_sessions; mds++) { + struct ceph_mds_session *session = mdsc->sessions[mds]; + struct inode *inode = NULL; + + 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); + + if (!check_cap_flush(&ci->vfs_inode, want_flush_seq)) { + dout("check_cap_flush still flushing %p " + "seq %lld <= %lld to mds%d\n", + &ci->vfs_inode, ci->i_cap_flush_seq, + want_flush_seq, session->s_mds); + inode = igrab(&ci->vfs_inode); + } + } + mutex_unlock(&session->s_mutex); + ceph_put_mds_session(session); + + if (inode) { + wait_event(mdsc->cap_flushing_wq, + check_cap_flush(inode, want_flush_seq)); + iput(inode); + } + + mutex_lock(&mdsc->mutex); + } + + mutex_unlock(&mdsc->mutex); + dout("check_cap_flush ok, flushed thru %lld\n", want_flush_seq); +} + +/* + * called under s_mutex + */ +void ceph_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); + spin_lock(&session->s_cap_lock); + 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); + 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_lock(&session->s_cap_lock); + } + spin_unlock(&session->s_cap_lock); +} + +static void discard_cap_releases(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session) +{ + struct ceph_msg *msg; + struct ceph_mds_cap_release *head; + unsigned num; + + dout("discard_cap_releases mds%d\n", session->s_mds); + + if (!list_empty(&session->s_cap_releases)) { + /* zero out the in-progress message */ + msg = list_first_entry(&session->s_cap_releases, + struct ceph_msg, list_head); + head = msg->front.iov_base; + num = le32_to_cpu(head->num); + dout("discard_cap_releases mds%d %p %u\n", + session->s_mds, msg, num); + head->num = cpu_to_le32(0); + msg->front.iov_len = sizeof(*head); + session->s_num_cap_releases += num; + } + + /* requeue completed messages */ + 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); + + head = msg->front.iov_base; + num = le32_to_cpu(head->num); + dout("discard_cap_releases mds%d %p %u\n", session->s_mds, msg, + num); + session->s_num_cap_releases += num; + head->num = cpu_to_le32(0); + msg->front.iov_len = sizeof(*head); + list_add(&msg->list_head, &session->s_cap_releases); + } +} + +/* + * 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(*rinfo->dir_in) + sizeof(*rinfo->dir_dname_len) + + sizeof(*rinfo->dir_dname) + sizeof(*rinfo->dir_dlease); + 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_in = (void*)__get_free_pages(GFP_NOFS | __GFP_NOWARN, + order); + if (rinfo->dir_in) + break; + order--; + } + if (!rinfo->dir_in) + 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); + + 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); + 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_stamp = CURRENT_TIME; + + 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; + unsigned seq; + + if (dentry == NULL) + 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 == NULL) + 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; +} + +static int build_dentry_path(struct dentry *dentry, + const char **ppath, int *ppathlen, u64 *pino, + int *pfreepath) +{ + char *path; + + if (ceph_snap(d_inode(dentry->d_parent)) == CEPH_NOSNAP) { + *pino = ceph_ino(d_inode(dentry->d_parent)); + *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 || 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; + 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)) + + sizeof(struct 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_new(CEPH_MSG_CLIENT_REQUEST, len, 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, + 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, + 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_timespec(&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; + atomic_inc(&pagelist->refcnt); + 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 (req->r_got_unsafe) { + 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_timespec(&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); + 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; + rhead->ino = 0; + + dout(" r_locked_dir = %p\n", req->r_locked_dir); + 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_err || req->r_got_result) { + if (req->r_aborted) + __unregister_request(mdsc, req); + 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; + } + + 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); + 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; + } + } + 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_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); +out: + return err; + +finish: + req->r_err = 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; + 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 (req->r_got_unsafe) + 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_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_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; + __unregister_request(mdsc, req); + dout("do_request early error %d\n", err); + goto out; + } + + /* wait */ + mutex_unlock(&mdsc->mutex); + dout("do_request waiting\n"); + if (req->r_timeout) { + err = (long)wait_for_completion_killable_timeout( + &req->r_completion, req->r_timeout); + if (err == 0) + err = -EIO; + } else if (req->r_wait_for_completion) { + err = req->r_wait_for_completion(mdsc, req); + } else { + err = wait_for_completion_killable(&req->r_completion); + } + dout("do_request waited, got %d\n", err); + mutex_lock(&mdsc->mutex); + + /* only abort if we didn't race with a real reply */ + if (req->r_got_result) { + 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; + req->r_aborted = true; + mutex_unlock(&req->r_fill_mutex); + + if (req->r_locked_dir && + (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 *inode = req->r_locked_dir; + + dout("invalidate_dir_request %p (complete, lease(s))\n", inode); + + ceph_dir_clear_complete(inode); + 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_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_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 (req->r_got_safe && !head->safe) { + 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", req->r_tid); + req->r_resend_mds = -1; + if (req->r_direct_mode != USE_AUTH_MDS) { + dout("not using auth, setting for that now"); + 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"); + __do_request(mdsc, req); + mutex_unlock(&mdsc->mutex); + goto out; + } + } + dout("have to return ESTALE on request %llu", req->r_tid); + } + + + if (head->safe) { + req->r_got_safe = true; + __unregister_request(mdsc, req); + + 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_all(&mdsc->safe_umount_waiters); + mutex_unlock(&mdsc->mutex); + goto out; + } + } else { + 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, 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); + err = ceph_fill_trace(mdsc->fsc->sb, req, req->r_session); + 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); + ceph_unreserve_caps(mdsc, &req->r_caps_reservation); + } + mutex_unlock(&req->r_fill_mutex); + + up_read(&mdsc->snap_rwsem); + if (realm) + ceph_put_snap_realm(mdsc, realm); +out_err: + mutex_lock(&mdsc->mutex); + if (!req->r_aborted) { + if (err) { + req->r_err = err; + } else { + req->r_reply = msg; + ceph_msg_get(msg); + req->r_got_result = true; + } + } else { + dout("reply arrived after request %lld was aborted\n", tid); + } + mutex_unlock(&mdsc->mutex); + + ceph_add_cap_releases(mdsc, req->r_session); + 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 tid %llu to mds%d - req dne\n", tid, next_mds); + goto out; /* dup reply? */ + } + + if (req->r_aborted) { + dout("forward tid %llu aborted, unregistering\n", tid); + __unregister_request(mdsc, req); + } else if (fwd_seq <= req->r_num_fwd) { + dout("forward tid %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 tid %llu to mds%d (we resend)\n", tid, next_mds); + BUG_ON(req->r_err); + BUG_ON(req->r_got_result); + req->r_attempts = 0; + 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, + ceph_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: + if (session->s_state == CEPH_MDS_SESSION_RECONNECTING) + pr_info("mds%d reconnect success\n", session->s_mds); + 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: + if (session->s_state == CEPH_MDS_SESSION_RECONNECTING) + pr_info("mds%d reconnect denied\n", session->s_mds); + cleanup_session_requests(mdsc, session); + remove_session_caps(session); + wake = 2; /* for good measure */ + wake_up_all(&mdsc->session_close_wq); + break; + + case CEPH_SESSION_STALE: + pr_info("mds%d caps went stale, renewing\n", + session->s_mds); + spin_lock(&session->s_gen_ttl_lock); + session->s_cap_gen++; + session->s_cap_ttl = jiffies - 1; + spin_unlock(&session->s_gen_ttl_lock); + send_renew_caps(mdsc, session); + break; + + case CEPH_SESSION_RECALL_STATE: + trim_caps(mdsc, session, le32_to_cpu(h->max_caps)); + break; + + case CEPH_SESSION_FLUSHMSG: + send_flushmsg_ack(mdsc, session, seq); + break; + + case CEPH_SESSION_FORCE_RO: + dout("force_session_readonly %p\n", session); + spin_lock(&session->s_cap_lock); + session->s_readonly = true; + spin_unlock(&session->s_cap_lock); + wake_up_session_caps(session, 0); + 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); + if (wake == 2) + kick_requests(mdsc, mds); + 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; + struct rb_node *p; + 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, true); + if (!err) { + ceph_msg_get(req->r_request); + ceph_con_send(&session->s_con, req->r_request); + } + } + + /* + * also re-send old requests when MDS enters reconnect stage. So that MDS + * can process completed request in clientreplay stage. + */ + 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_got_unsafe) + continue; + if (req->r_attempts == 0) + continue; /* only old requests */ + if (req->r_session && + req->r_session->s_mds == session->s_mds) { + err = __prepare_send_request(mdsc, req, + session->s_mds, true); + 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) +{ + union { + struct ceph_mds_cap_reconnect v2; + struct ceph_mds_cap_reconnect_v1 v1; + } rec; + size_t reclen; + struct ceph_inode_info *ci; + struct ceph_reconnect_state *recon_state = arg; + struct ceph_pagelist *pagelist = recon_state->pagelist; + 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); + goto out_dput; + } + } else { + path = NULL; + pathlen = 0; + } + err = ceph_pagelist_encode_string(pagelist, path, pathlen); + if (err) + goto out_free; + + spin_lock(&ci->i_ceph_lock); + cap->seq = 0; /* reset cap seq */ + cap->issue_seq = 0; /* and issue_seq */ + cap->mseq = 0; /* and migrate_seq */ + cap->cap_gen = cap->session->s_cap_gen; + + if (recon_state->flock) { + rec.v2.cap_id = cpu_to_le64(cap->cap_id); + rec.v2.wanted = cpu_to_le32(__ceph_caps_wanted(ci)); + rec.v2.issued = cpu_to_le32(cap->issued); + rec.v2.snaprealm = cpu_to_le64(ci->i_snap_realm->ino); + rec.v2.pathbase = cpu_to_le64(pathbase); + rec.v2.flock_len = 0; + reclen = sizeof(rec.v2); + } else { + rec.v1.cap_id = cpu_to_le64(cap->cap_id); + rec.v1.wanted = cpu_to_le32(__ceph_caps_wanted(ci)); + rec.v1.issued = cpu_to_le32(cap->issued); + rec.v1.size = cpu_to_le64(inode->i_size); + ceph_encode_timespec(&rec.v1.mtime, &inode->i_mtime); + ceph_encode_timespec(&rec.v1.atime, &inode->i_atime); + rec.v1.snaprealm = cpu_to_le64(ci->i_snap_realm->ino); + rec.v1.pathbase = cpu_to_le64(pathbase); + reclen = sizeof(rec.v1); + } + spin_unlock(&ci->i_ceph_lock); + + if (recon_state->flock) { + int num_fcntl_locks, num_flock_locks; + struct ceph_filelock *flocks; + +encode_again: + ceph_count_locks(inode, &num_fcntl_locks, &num_flock_locks); + flocks = kmalloc((num_fcntl_locks+num_flock_locks) * + sizeof(struct ceph_filelock), GFP_NOFS); + if (!flocks) { + err = -ENOMEM; + goto out_free; + } + err = ceph_encode_locks_to_buffer(inode, flocks, + num_fcntl_locks, + num_flock_locks); + if (err) { + kfree(flocks); + if (err == -ENOSPC) + goto encode_again; + goto out_free; + } + /* + * number of encoded locks is stable, so copy to pagelist + */ + rec.v2.flock_len = cpu_to_le32(2*sizeof(u32) + + (num_fcntl_locks+num_flock_locks) * + sizeof(struct ceph_filelock)); + err = ceph_pagelist_append(pagelist, &rec, reclen); + if (!err) + err = ceph_locks_to_pagelist(flocks, pagelist, + num_fcntl_locks, + num_flock_locks); + kfree(flocks); + } else { + err = ceph_pagelist_append(pagelist, &rec, reclen); + } + + recon_state->nr_caps++; +out_free: + kfree(path); +out_dput: + 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, + struct ceph_mds_session *session) +{ + struct ceph_msg *reply; + struct rb_node *p; + int mds = session->s_mds; + int err = -ENOMEM; + int s_nr_caps; + struct ceph_pagelist *pagelist; + struct ceph_reconnect_state recon_state; + + pr_info("mds%d reconnect start\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, GFP_NOFS, false); + if (!reply) + goto fail_nomsg; + + mutex_lock(&session->s_mutex); + session->s_state = CEPH_MDS_SESSION_RECONNECTING; + session->s_seq = 0; + + dout("session %p state %s\n", session, + ceph_session_state_name(session->s_state)); + + spin_lock(&session->s_gen_ttl_lock); + session->s_cap_gen++; + spin_unlock(&session->s_gen_ttl_lock); + + spin_lock(&session->s_cap_lock); + /* don't know if session is readonly */ + session->s_readonly = 0; + /* + * notify __ceph_remove_cap() that we are composing cap reconnect. + * If a cap get released before being added to the cap reconnect, + * __ceph_remove_cap() should skip queuing cap release. + */ + session->s_cap_reconnect = 1; + /* drop old cap expires; we're about to reestablish that state */ + discard_cap_releases(mdsc, session); + spin_unlock(&session->s_cap_lock); + + /* trim unused caps to reduce MDS's cache rejoin time */ + if (mdsc->fsc->sb->s_root) + shrink_dcache_parent(mdsc->fsc->sb->s_root); + + ceph_con_close(&session->s_con); + ceph_con_open(&session->s_con, + CEPH_ENTITY_TYPE_MDS, mds, + ceph_mdsmap_get_addr(mdsc->mdsmap, mds)); + + /* replay unsafe requests */ + replay_unsafe_requests(mdsc, session); + + down_read(&mdsc->snap_rwsem); + + /* traverse this session's caps */ + s_nr_caps = session->s_nr_caps; + err = ceph_pagelist_encode_32(pagelist, s_nr_caps); + if (err) + goto fail; + + recon_state.nr_caps = 0; + recon_state.pagelist = pagelist; + recon_state.flock = session->s_con.peer_features & CEPH_FEATURE_FLOCK; + err = iterate_session_caps(session, encode_caps_cb, &recon_state); + if (err < 0) + goto fail; + + spin_lock(&session->s_cap_lock); + session->s_cap_reconnect = 0; + spin_unlock(&session->s_cap_lock); + + /* + * 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; + } + + if (recon_state.flock) + reply->hdr.version = cpu_to_le16(2); + + /* raced with cap release? */ + if (s_nr_caps != recon_state.nr_caps) { + struct page *page = list_first_entry(&pagelist->head, + struct page, lru); + __le32 *addr = kmap_atomic(page); + *addr = cpu_to_le32(recon_state.nr_caps); + kunmap_atomic(addr); + } + + reply->hdr.data_len = cpu_to_le32(pagelist->length); + ceph_msg_data_add_pagelist(reply, pagelist); + ceph_con_send(&session->s_con, reply); + + mutex_unlock(&session->s_mutex); + + mutex_lock(&mdsc->mutex); + __wake_requests(mdsc, &session->s_waiting); + mutex_unlock(&mdsc->mutex); + + up_read(&mdsc->snap_rwsem); + return; + +fail: + ceph_msg_put(reply); + up_read(&mdsc->snap_rwsem); + mutex_unlock(&session->s_mutex); +fail_nomsg: + ceph_pagelist_release(pagelist); +fail_nopagelist: + pr_err("error %d preparing reconnect for mds%d\n", err, mds); + 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 -> %s%s (session %s)\n", + i, ceph_mds_state_name(oldstate), + ceph_mdsmap_is_laggy(oldmap, i) ? " (laggy)" : "", + ceph_mds_state_name(newstate), + ceph_mdsmap_is_laggy(newmap, i) ? " (laggy)" : "", + ceph_session_state_name(s->s_state)); + + if (i >= newmap->m_max_mds || + 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; + } + } 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) { + mutex_unlock(&mdsc->mutex); + send_mds_reconnect(mdsc, s); + mutex_lock(&mdsc->mutex); + } + + /* + * kick request on any mds that has gone active. + */ + if (oldstate < CEPH_MDS_STATE_ACTIVE && + newstate >= CEPH_MDS_STATE_ACTIVE) { + if (oldstate != CEPH_MDS_STATE_CREATING && + oldstate != CEPH_MDS_STATE_STARTING) + pr_info("mds%d recovery completed\n", s->s_mds); + kick_requests(mdsc, i); + ceph_kick_flushing_caps(mdsc, s); + wake_up_session_caps(s, 1); + } + } + + for (i = 0; i < newmap->m_max_mds && i < mdsc->max_sessions; i++) { + s = mdsc->sessions[i]; + if (!s) + continue; + if (!ceph_mdsmap_is_laggy(newmap, i)) + continue; + if (s->s_state == CEPH_MDS_SESSION_OPEN || + s->s_state == CEPH_MDS_SESSION_HUNG || + s->s_state == CEPH_MDS_SESSION_CLOSING) { + dout(" connecting to export targets of laggy mds%d\n", + i); + __open_export_target_sessions(mdsc, s); + } + } +} + + + +/* + * 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->fsc->sb; + struct inode *inode; + struct dentry *parent, *dentry; + struct ceph_dentry_info *di; + int mds = session->s_mds; + struct ceph_mds_lease *h = msg->front.iov_base; + u32 seq; + struct ceph_vino vino; + 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; + seq = le32_to_cpu(h->seq); + 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; + + /* lookup inode */ + inode = ceph_find_inode(sb, vino); + dout("handle_lease %s, ino %llx %p %.*s\n", + ceph_lease_op_name(h->action), vino.ino, inode, + dname.len, dname.name); + + mutex_lock(&session->s_mutex); + session->s_seq++; + + if (inode == NULL) { + dout("handle_lease no inode %llx\n", vino.ino); + goto release; + } + + /* 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->lease_session == session) { + if (ceph_seq_cmp(di->lease_seq, seq) > 0) + h->seq = cpu_to_le32(di->lease_seq); + __ceph_mdsc_drop_dentry_lease(dentry); + } + release = 1; + break; + + case CEPH_MDS_LEASE_RENEW: + if (di->lease_session == session && + di->lease_gen == session->s_cap_gen && + di->lease_renew_from && + di->lease_renew_after == 0) { + unsigned long duration = + msecs_to_jiffies(le32_to_cpu(h->duration_ms)); + + di->lease_seq = 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, GFP_NOFS, false); + if (!msg) + return; + lease = msg->front.iov_base; + lease->action = action; + 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) +{ + struct ceph_dentry_info *di; + struct ceph_mds_session *session; + u32 seq; + + BUG_ON(inode == NULL); + BUG_ON(dentry == NULL); + + /* 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\n", + inode, dentry); + 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 to mds%d\n", + inode, dentry, 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); + ceph_add_cap_releases(mdsc, s); + if (s->s_state == CEPH_MDS_SESSION_OPEN || + s->s_state == CEPH_MDS_SESSION_HUNG) + ceph_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_fs_client *fsc) + +{ + struct ceph_mds_client *mdsc; + + mdsc = kzalloc(sizeof(struct ceph_mds_client), GFP_NOFS); + if (!mdsc) + return -ENOMEM; + mdsc->fsc = fsc; + fsc->mdsc = mdsc; + mutex_init(&mdsc->mutex); + mdsc->mdsmap = kzalloc(sizeof(*mdsc->mdsmap), GFP_NOFS); + if (mdsc->mdsmap == NULL) { + kfree(mdsc); + return -ENOMEM; + } + + init_completion(&mdsc->safe_umount_waiters); + init_waitqueue_head(&mdsc->session_close_wq); + INIT_LIST_HEAD(&mdsc->waiting_for_map); + mdsc->sessions = NULL; + atomic_set(&mdsc->num_sessions, 0); + 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); + INIT_LIST_HEAD(&mdsc->cap_dirty_migrating); + 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); + + ceph_caps_init(mdsc); + ceph_adjust_min_caps(mdsc, fsc->min_caps); + + 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_fs_client *fsc = mdsc->fsc; + + 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, + fsc->client->options->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 reply handlers to drop their request refs and + * their inode/dcache refs + */ + ceph_msgr_flush(); +} + +/* + * 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; + + if (mdsc->fsc->mount_state == CEPH_MOUNT_SHUTDOWN) + return; + + dout("sync\n"); + mutex_lock(&mdsc->mutex); + want_tid = mdsc->last_tid; + mutex_unlock(&mdsc->mutex); + + ceph_flush_dirty_caps(mdsc); + spin_lock(&mdsc->cap_dirty_lock); + want_flush = mdsc->cap_flush_seq; + spin_unlock(&mdsc->cap_dirty_lock); + + dout("sync want tid %lld flush_seq %lld\n", want_tid, want_flush); + + wait_unsafe_requests(mdsc, want_tid); + wait_caps_flush(mdsc, want_flush); +} + +/* + * true if all sessions are closed, or we force unmount + */ +static bool done_closing_sessions(struct ceph_mds_client *mdsc) +{ + if (mdsc->fsc->mount_state == CEPH_MOUNT_SHUTDOWN) + return true; + return atomic_read(&mdsc->num_sessions) == 0; +} + +/* + * called after sb is ro. + */ +void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc) +{ + struct ceph_mds_session *session; + int i; + struct ceph_fs_client *fsc = mdsc->fsc; + unsigned long timeout = fsc->client->options->mount_timeout * HZ; + + dout("close_sessions\n"); + + /* close sessions */ + mutex_lock(&mdsc->mutex); + 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); + } + mutex_unlock(&mdsc->mutex); + + dout("waiting for sessions to close\n"); + wait_event_timeout(mdsc->session_close_wq, done_closing_sessions(mdsc), + timeout); + + /* tear down remaining sessions */ + mutex_lock(&mdsc->mutex); + 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"); +} + +static 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); + ceph_caps_finalize(mdsc); +} + +void ceph_mdsc_destroy(struct ceph_fs_client *fsc) +{ + struct ceph_mds_client *mdsc = fsc->mdsc; + + dout("mdsc_destroy %p\n", mdsc); + ceph_mdsc_stop(mdsc); + + /* flush out any connection work with references to us */ + ceph_msgr_flush(); + + fsc->mdsc = NULL; + kfree(mdsc); + dout("mdsc_destroy %p done\n", mdsc); +} + + +/* + * 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->fsc->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->fsc->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->fsc->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; + + dout("mdsc con_put %p (%d)\n", s, atomic_read(&s->s_ref) - 1); + ceph_put_mds_session(s); +} + +/* + * 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; + struct ceph_mds_client *mdsc = s->s_mdsc; + + pr_warn("mds%d closed our session\n", s->s_mds); + send_mds_reconnect(mdsc, s); +} + +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 + */ + +/* + * Note: returned pointer is the address of a structure that's + * managed separately. Caller must *not* attempt to free it. + */ +static struct ceph_auth_handshake *get_authorizer(struct ceph_connection *con, + int *proto, int force_new) +{ + struct ceph_mds_session *s = con->private; + struct ceph_mds_client *mdsc = s->s_mdsc; + struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth; + struct ceph_auth_handshake *auth = &s->s_auth; + + if (force_new && auth->authorizer) { + ceph_auth_destroy_authorizer(ac, auth->authorizer); + auth->authorizer = NULL; + } + if (!auth->authorizer) { + int ret = ceph_auth_create_authorizer(ac, CEPH_ENTITY_TYPE_MDS, + auth); + if (ret) + return ERR_PTR(ret); + } else { + int ret = ceph_auth_update_authorizer(ac, CEPH_ENTITY_TYPE_MDS, + auth); + if (ret) + return ERR_PTR(ret); + } + *proto = ac->protocol; + + return auth; +} + + +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->fsc->client->monc.auth; + + return ceph_auth_verify_authorizer_reply(ac, s->s_auth.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->fsc->client->monc.auth; + + ceph_auth_invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS); + + return ceph_monc_validate_auth(&mdsc->fsc->client->monc); +} + +static struct ceph_msg *mds_alloc_msg(struct ceph_connection *con, + struct ceph_msg_header *hdr, int *skip) +{ + struct ceph_msg *msg; + int type = (int) le16_to_cpu(hdr->type); + int front_len = (int) le32_to_cpu(hdr->front_len); + + if (con->in_msg) + return con->in_msg; + + *skip = 0; + msg = ceph_msg_new(type, front_len, GFP_NOFS, false); + if (!msg) { + pr_err("unable to allocate msg type %d len %d\n", + type, front_len); + return NULL; + } + + return msg; +} + +static int sign_message(struct ceph_connection *con, struct ceph_msg *msg) +{ + struct ceph_mds_session *s = con->private; + struct ceph_auth_handshake *auth = &s->s_auth; + return ceph_auth_sign_message(auth, msg); +} + +static int check_message_signature(struct ceph_connection *con, struct ceph_msg *msg) +{ + struct ceph_mds_session *s = con->private; + struct ceph_auth_handshake *auth = &s->s_auth; + return ceph_auth_check_message_signature(auth, msg); +} + +static const 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, + .alloc_msg = mds_alloc_msg, + .sign_message = sign_message, + .check_message_signature = check_message_signature, +}; + +/* eof */ |