diff options
Diffstat (limited to 'fs/ceph/mds_client.c')
| -rw-r--r-- | fs/ceph/mds_client.c | 5275 |
1 files changed, 5275 insertions, 0 deletions
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c new file mode 100644 index 000000000..df1ecb8bf --- /dev/null +++ b/fs/ceph/mds_client.c @@ -0,0 +1,5275 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/ceph/ceph_debug.h> + +#include <linux/fs.h> +#include <linux/wait.h> +#include <linux/slab.h> +#include <linux/gfp.h> +#include <linux/sched.h> +#include <linux/debugfs.h> +#include <linux/seq_file.h> +#include <linux/ratelimit.h> +#include <linux/bits.h> +#include <linux/ktime.h> + +#include "super.h" +#include "mds_client.h" + +#include <linux/ceph/ceph_features.h> +#include <linux/ceph/messenger.h> +#include <linux/ceph/decode.h> +#include <linux/ceph/pagelist.h> +#include <linux/ceph/auth.h> +#include <linux/ceph/debugfs.h> + +#define RECONNECT_MAX_SIZE (INT_MAX - PAGE_SIZE) + +/* + * A cluster of MDS (metadata server) daemons is responsible for + * managing the file system namespace (the directory hierarchy and + * inodes) and for coordinating shared access to storage. Metadata is + * partitioning hierarchically across a number of servers, and that + * partition varies over time as the cluster adjusts the distribution + * in order to balance load. + * + * The MDS client is primarily responsible to managing synchronous + * metadata requests for operations like open, unlink, and so forth. + * If there is a MDS failure, we find out about it when we (possibly + * request and) receive a new MDS map, and can resubmit affected + * requests. + * + * For the most part, though, we take advantage of a lossless + * communications channel to the MDS, and do not need to worry about + * timing out or resubmitting requests. + * + * We maintain a stateful "session" with each MDS we interact with. + * Within each session, we sent periodic heartbeat messages to ensure + * any capabilities or leases we have been issues remain valid. If + * the session times out and goes stale, our leases and capabilities + * are no longer valid. + */ + +struct ceph_reconnect_state { + struct ceph_mds_session *session; + int nr_caps, nr_realms; + struct ceph_pagelist *pagelist; + unsigned msg_version; + bool allow_multi; +}; + +static void __wake_requests(struct ceph_mds_client *mdsc, + struct list_head *head); +static void ceph_cap_release_work(struct work_struct *work); +static void ceph_cap_reclaim_work(struct work_struct *work); + +static const struct ceph_connection_operations mds_con_ops; + + +/* + * mds reply parsing + */ + +static int parse_reply_info_quota(void **p, void *end, + struct ceph_mds_reply_info_in *info) +{ + u8 struct_v, struct_compat; + u32 struct_len; + + ceph_decode_8_safe(p, end, struct_v, bad); + ceph_decode_8_safe(p, end, struct_compat, bad); + /* struct_v is expected to be >= 1. we only + * understand encoding with struct_compat == 1. */ + if (!struct_v || struct_compat != 1) + goto bad; + ceph_decode_32_safe(p, end, struct_len, bad); + ceph_decode_need(p, end, struct_len, bad); + end = *p + struct_len; + ceph_decode_64_safe(p, end, info->max_bytes, bad); + ceph_decode_64_safe(p, end, info->max_files, bad); + *p = end; + return 0; +bad: + return -EIO; +} + +/* + * parse individual inode info + */ +static int parse_reply_info_in(void **p, void *end, + struct ceph_mds_reply_info_in *info, + u64 features) +{ + int err = 0; + u8 struct_v = 0; + + if (features == (u64)-1) { + u32 struct_len; + u8 struct_compat; + ceph_decode_8_safe(p, end, struct_v, bad); + ceph_decode_8_safe(p, end, struct_compat, bad); + /* struct_v is expected to be >= 1. we only understand + * encoding with struct_compat == 1. */ + if (!struct_v || struct_compat != 1) + goto bad; + ceph_decode_32_safe(p, end, struct_len, bad); + ceph_decode_need(p, end, struct_len, bad); + end = *p + struct_len; + } + + ceph_decode_need(p, end, sizeof(struct ceph_mds_reply_inode), bad); + info->in = *p; + *p += sizeof(struct ceph_mds_reply_inode) + + sizeof(*info->in->fragtree.splits) * + le32_to_cpu(info->in->fragtree.nsplits); + + ceph_decode_32_safe(p, end, info->symlink_len, bad); + ceph_decode_need(p, end, info->symlink_len, bad); + info->symlink = *p; + *p += info->symlink_len; + + ceph_decode_copy_safe(p, end, &info->dir_layout, + sizeof(info->dir_layout), bad); + ceph_decode_32_safe(p, end, info->xattr_len, bad); + ceph_decode_need(p, end, info->xattr_len, bad); + info->xattr_data = *p; + *p += info->xattr_len; + + if (features == (u64)-1) { + /* inline data */ + ceph_decode_64_safe(p, end, info->inline_version, bad); + ceph_decode_32_safe(p, end, info->inline_len, bad); + ceph_decode_need(p, end, info->inline_len, bad); + info->inline_data = *p; + *p += info->inline_len; + /* quota */ + err = parse_reply_info_quota(p, end, info); + if (err < 0) + goto out_bad; + /* pool namespace */ + ceph_decode_32_safe(p, end, info->pool_ns_len, bad); + if (info->pool_ns_len > 0) { + ceph_decode_need(p, end, info->pool_ns_len, bad); + info->pool_ns_data = *p; + *p += info->pool_ns_len; + } + + /* btime */ + ceph_decode_need(p, end, sizeof(info->btime), bad); + ceph_decode_copy(p, &info->btime, sizeof(info->btime)); + + /* change attribute */ + ceph_decode_64_safe(p, end, info->change_attr, bad); + + /* dir pin */ + if (struct_v >= 2) { + ceph_decode_32_safe(p, end, info->dir_pin, bad); + } else { + info->dir_pin = -ENODATA; + } + + /* snapshot birth time, remains zero for v<=2 */ + if (struct_v >= 3) { + ceph_decode_need(p, end, sizeof(info->snap_btime), bad); + ceph_decode_copy(p, &info->snap_btime, + sizeof(info->snap_btime)); + } else { + memset(&info->snap_btime, 0, sizeof(info->snap_btime)); + } + + *p = end; + } else { + if (features & CEPH_FEATURE_MDS_INLINE_DATA) { + ceph_decode_64_safe(p, end, info->inline_version, bad); + ceph_decode_32_safe(p, end, info->inline_len, bad); + ceph_decode_need(p, end, info->inline_len, bad); + info->inline_data = *p; + *p += info->inline_len; + } else + info->inline_version = CEPH_INLINE_NONE; + + if (features & CEPH_FEATURE_MDS_QUOTA) { + err = parse_reply_info_quota(p, end, info); + if (err < 0) + goto out_bad; + } else { + info->max_bytes = 0; + info->max_files = 0; + } + + info->pool_ns_len = 0; + info->pool_ns_data = NULL; + if (features & CEPH_FEATURE_FS_FILE_LAYOUT_V2) { + ceph_decode_32_safe(p, end, info->pool_ns_len, bad); + if (info->pool_ns_len > 0) { + ceph_decode_need(p, end, info->pool_ns_len, bad); + info->pool_ns_data = *p; + *p += info->pool_ns_len; + } + } + + if (features & CEPH_FEATURE_FS_BTIME) { + ceph_decode_need(p, end, sizeof(info->btime), bad); + ceph_decode_copy(p, &info->btime, sizeof(info->btime)); + ceph_decode_64_safe(p, end, info->change_attr, bad); + } + + info->dir_pin = -ENODATA; + /* info->snap_btime remains zero */ + } + return 0; +bad: + err = -EIO; +out_bad: + return err; +} + +static int parse_reply_info_dir(void **p, void *end, + struct ceph_mds_reply_dirfrag **dirfrag, + u64 features) +{ + if (features == (u64)-1) { + u8 struct_v, struct_compat; + u32 struct_len; + ceph_decode_8_safe(p, end, struct_v, bad); + ceph_decode_8_safe(p, end, struct_compat, bad); + /* struct_v is expected to be >= 1. we only understand + * encoding whose struct_compat == 1. */ + if (!struct_v || struct_compat != 1) + goto bad; + ceph_decode_32_safe(p, end, struct_len, bad); + ceph_decode_need(p, end, struct_len, bad); + end = *p + struct_len; + } + + ceph_decode_need(p, end, sizeof(**dirfrag), bad); + *dirfrag = *p; + *p += sizeof(**dirfrag) + sizeof(u32) * le32_to_cpu((*dirfrag)->ndist); + if (unlikely(*p > end)) + goto bad; + if (features == (u64)-1) + *p = end; + return 0; +bad: + return -EIO; +} + +static int parse_reply_info_lease(void **p, void *end, + struct ceph_mds_reply_lease **lease, + u64 features) +{ + if (features == (u64)-1) { + u8 struct_v, struct_compat; + u32 struct_len; + ceph_decode_8_safe(p, end, struct_v, bad); + ceph_decode_8_safe(p, end, struct_compat, bad); + /* struct_v is expected to be >= 1. we only understand + * encoding whose struct_compat == 1. */ + if (!struct_v || struct_compat != 1) + goto bad; + ceph_decode_32_safe(p, end, struct_len, bad); + ceph_decode_need(p, end, struct_len, bad); + end = *p + struct_len; + } + + ceph_decode_need(p, end, sizeof(**lease), bad); + *lease = *p; + *p += sizeof(**lease); + if (features == (u64)-1) + *p = end; + return 0; +bad: + return -EIO; +} + +/* + * parse a normal reply, which may contain a (dir+)dentry and/or a + * target inode. + */ +static int parse_reply_info_trace(void **p, void *end, + struct ceph_mds_reply_info_parsed *info, + u64 features) +{ + int err; + + if (info->head->is_dentry) { + err = parse_reply_info_in(p, end, &info->diri, features); + if (err < 0) + goto out_bad; + + err = parse_reply_info_dir(p, end, &info->dirfrag, features); + if (err < 0) + goto out_bad; + + ceph_decode_32_safe(p, end, info->dname_len, bad); + ceph_decode_need(p, end, info->dname_len, bad); + info->dname = *p; + *p += info->dname_len; + + err = parse_reply_info_lease(p, end, &info->dlease, features); + if (err < 0) + goto out_bad; + } + + if (info->head->is_target) { + err = parse_reply_info_in(p, end, &info->targeti, features); + if (err < 0) + goto out_bad; + } + + if (unlikely(*p != end)) + goto bad; + return 0; + +bad: + err = -EIO; +out_bad: + pr_err("problem parsing mds trace %d\n", err); + return err; +} + +/* + * parse readdir results + */ +static int parse_reply_info_readdir(void **p, void *end, + struct ceph_mds_reply_info_parsed *info, + u64 features) +{ + u32 num, i = 0; + int err; + + err = parse_reply_info_dir(p, end, &info->dir_dir, features); + if (err < 0) + goto out_bad; + + ceph_decode_need(p, end, sizeof(num) + 2, bad); + num = ceph_decode_32(p); + { + u16 flags = ceph_decode_16(p); + info->dir_end = !!(flags & CEPH_READDIR_FRAG_END); + info->dir_complete = !!(flags & CEPH_READDIR_FRAG_COMPLETE); + info->hash_order = !!(flags & CEPH_READDIR_HASH_ORDER); + info->offset_hash = !!(flags & CEPH_READDIR_OFFSET_HASH); + } + if (num == 0) + goto done; + + BUG_ON(!info->dir_entries); + if ((unsigned long)(info->dir_entries + num) > + (unsigned long)info->dir_entries + info->dir_buf_size) { + pr_err("dir contents are larger than expected\n"); + WARN_ON(1); + goto bad; + } + + info->dir_nr = num; + while (num) { + struct ceph_mds_reply_dir_entry *rde = info->dir_entries + i; + /* dentry */ + ceph_decode_32_safe(p, end, rde->name_len, bad); + ceph_decode_need(p, end, rde->name_len, bad); + rde->name = *p; + *p += rde->name_len; + dout("parsed dir dname '%.*s'\n", rde->name_len, rde->name); + + /* dentry lease */ + err = parse_reply_info_lease(p, end, &rde->lease, features); + if (err) + goto out_bad; + /* inode */ + err = parse_reply_info_in(p, end, &rde->inode, features); + if (err < 0) + goto out_bad; + /* ceph_readdir_prepopulate() will update it */ + rde->offset = 0; + i++; + num--; + } + +done: + /* Skip over any unrecognized fields */ + *p = end; + 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; + + /* Skip over any unrecognized fields */ + *p = end; + return 0; +bad: + return -EIO; +} + + +#if BITS_PER_LONG == 64 + +#define DELEGATED_INO_AVAILABLE xa_mk_value(1) + +static int ceph_parse_deleg_inos(void **p, void *end, + struct ceph_mds_session *s) +{ + u32 sets; + + ceph_decode_32_safe(p, end, sets, bad); + dout("got %u sets of delegated inodes\n", sets); + while (sets--) { + u64 start, len, ino; + + ceph_decode_64_safe(p, end, start, bad); + ceph_decode_64_safe(p, end, len, bad); + + /* Don't accept a delegation of system inodes */ + if (start < CEPH_INO_SYSTEM_BASE) { + pr_warn_ratelimited("ceph: ignoring reserved inode range delegation (start=0x%llx len=0x%llx)\n", + start, len); + continue; + } + while (len--) { + int err = xa_insert(&s->s_delegated_inos, ino = start++, + DELEGATED_INO_AVAILABLE, + GFP_KERNEL); + if (!err) { + dout("added delegated inode 0x%llx\n", + start - 1); + } else if (err == -EBUSY) { + pr_warn("ceph: MDS delegated inode 0x%llx more than once.\n", + start - 1); + } else { + return err; + } + } + } + return 0; +bad: + return -EIO; +} + +u64 ceph_get_deleg_ino(struct ceph_mds_session *s) +{ + unsigned long ino; + void *val; + + xa_for_each(&s->s_delegated_inos, ino, val) { + val = xa_erase(&s->s_delegated_inos, ino); + if (val == DELEGATED_INO_AVAILABLE) + return ino; + } + return 0; +} + +int ceph_restore_deleg_ino(struct ceph_mds_session *s, u64 ino) +{ + return xa_insert(&s->s_delegated_inos, ino, DELEGATED_INO_AVAILABLE, + GFP_KERNEL); +} +#else /* BITS_PER_LONG == 64 */ +/* + * FIXME: xarrays can't handle 64-bit indexes on a 32-bit arch. For now, just + * ignore delegated_inos on 32 bit arch. Maybe eventually add xarrays for top + * and bottom words? + */ +static int ceph_parse_deleg_inos(void **p, void *end, + struct ceph_mds_session *s) +{ + u32 sets; + + ceph_decode_32_safe(p, end, sets, bad); + if (sets) + ceph_decode_skip_n(p, end, sets * 2 * sizeof(__le64), bad); + return 0; +bad: + return -EIO; +} + +u64 ceph_get_deleg_ino(struct ceph_mds_session *s) +{ + return 0; +} + +int ceph_restore_deleg_ino(struct ceph_mds_session *s, u64 ino) +{ + return 0; +} +#endif /* BITS_PER_LONG == 64 */ + +/* + * parse create results + */ +static int parse_reply_info_create(void **p, void *end, + struct ceph_mds_reply_info_parsed *info, + u64 features, struct ceph_mds_session *s) +{ + int ret; + + if (features == (u64)-1 || + (features & CEPH_FEATURE_REPLY_CREATE_INODE)) { + if (*p == end) { + /* Malformed reply? */ + info->has_create_ino = false; + } else if (test_bit(CEPHFS_FEATURE_DELEG_INO, &s->s_features)) { + u8 struct_v, struct_compat; + u32 len; + + info->has_create_ino = true; + ceph_decode_8_safe(p, end, struct_v, bad); + ceph_decode_8_safe(p, end, struct_compat, bad); + ceph_decode_32_safe(p, end, len, bad); + ceph_decode_64_safe(p, end, info->ino, bad); + ret = ceph_parse_deleg_inos(p, end, s); + if (ret) + return ret; + } else { + /* legacy */ + ceph_decode_64_safe(p, end, info->ino, bad); + info->has_create_ino = true; + } + } else { + if (*p != end) + goto bad; + } + + /* Skip over any unrecognized fields */ + *p = end; + 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, struct ceph_mds_session *s) +{ + u32 op = le32_to_cpu(info->head->op); + + if (op == CEPH_MDS_OP_GETFILELOCK) + return parse_reply_info_filelock(p, end, info, features); + else if (op == CEPH_MDS_OP_READDIR || op == CEPH_MDS_OP_LSSNAP) + return parse_reply_info_readdir(p, end, info, features); + else if (op == CEPH_MDS_OP_CREATE) + return parse_reply_info_create(p, end, info, features, s); + else + return -EIO; +} + +/* + * parse entire mds reply + */ +static int parse_reply_info(struct ceph_mds_session *s, 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, s); + if (err < 0) + goto out_bad; + } + + /* snap blob */ + ceph_decode_32_safe(&p, end, len, bad); + info->snapblob_len = len; + info->snapblob = p; + p += len; + + if (p != end) + goto bad; + return 0; + +bad: + err = -EIO; +out_bad: + pr_err("mds parse_reply err %d\n", err); + return err; +} + +static void destroy_reply_info(struct ceph_mds_reply_info_parsed *info) +{ + if (!info->dir_entries) + return; + free_pages((unsigned long)info->dir_entries, get_order(info->dir_buf_size)); +} + + +/* + * sessions + */ +const char *ceph_session_state_name(int s) +{ + switch (s) { + case CEPH_MDS_SESSION_NEW: return "new"; + case CEPH_MDS_SESSION_OPENING: return "opening"; + case CEPH_MDS_SESSION_OPEN: return "open"; + case CEPH_MDS_SESSION_HUNG: return "hung"; + case CEPH_MDS_SESSION_CLOSING: return "closing"; + case CEPH_MDS_SESSION_CLOSED: return "closed"; + case CEPH_MDS_SESSION_RESTARTING: return "restarting"; + case CEPH_MDS_SESSION_RECONNECTING: return "reconnecting"; + case CEPH_MDS_SESSION_REJECTED: return "rejected"; + default: return "???"; + } +} + +struct ceph_mds_session *ceph_get_mds_session(struct ceph_mds_session *s) +{ + if (refcount_inc_not_zero(&s->s_ref)) { + dout("mdsc get_session %p %d -> %d\n", s, + refcount_read(&s->s_ref)-1, refcount_read(&s->s_ref)); + return s; + } else { + dout("mdsc get_session %p 0 -- FAIL\n", s); + return NULL; + } +} + +void ceph_put_mds_session(struct ceph_mds_session *s) +{ + if (IS_ERR_OR_NULL(s)) + return; + + dout("mdsc put_session %p %d -> %d\n", s, + refcount_read(&s->s_ref), refcount_read(&s->s_ref)-1); + if (refcount_dec_and_test(&s->s_ref)) { + if (s->s_auth.authorizer) + ceph_auth_destroy_authorizer(s->s_auth.authorizer); + WARN_ON(mutex_is_locked(&s->s_mutex)); + xa_destroy(&s->s_delegated_inos); + kfree(s); + } +} + +/* + * called under mdsc->mutex + */ +struct ceph_mds_session *__ceph_lookup_mds_session(struct ceph_mds_client *mdsc, + int mds) +{ + if (mds >= mdsc->max_sessions || !mdsc->sessions[mds]) + return NULL; + return ceph_get_mds_session(mdsc->sessions[mds]); +} + +static bool __have_session(struct ceph_mds_client *mdsc, int mds) +{ + if (mds >= mdsc->max_sessions || !mdsc->sessions[mds]) + return false; + else + return true; +} + +static int __verify_registered_session(struct ceph_mds_client *mdsc, + struct ceph_mds_session *s) +{ + if (s->s_mds >= mdsc->max_sessions || + mdsc->sessions[s->s_mds] != s) + return -ENOENT; + return 0; +} + +/* + * create+register a new session for given mds. + * called under mdsc->mutex. + */ +static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc, + int mds) +{ + struct ceph_mds_session *s; + + if (mds >= mdsc->mdsmap->possible_max_rank) + return ERR_PTR(-EINVAL); + + s = kzalloc(sizeof(*s), GFP_NOFS); + if (!s) + return ERR_PTR(-ENOMEM); + + if (mds >= mdsc->max_sessions) { + int newmax = 1 << get_count_order(mds + 1); + struct ceph_mds_session **sa; + + dout("%s: realloc to %d\n", __func__, newmax); + sa = kcalloc(newmax, sizeof(void *), GFP_NOFS); + if (!sa) + goto fail_realloc; + if (mdsc->sessions) { + memcpy(sa, mdsc->sessions, + mdsc->max_sessions * sizeof(void *)); + kfree(mdsc->sessions); + } + mdsc->sessions = sa; + mdsc->max_sessions = newmax; + } + + dout("%s: mds%d\n", __func__, mds); + s->s_mdsc = mdsc; + s->s_mds = mds; + s->s_state = CEPH_MDS_SESSION_NEW; + s->s_ttl = 0; + s->s_seq = 0; + mutex_init(&s->s_mutex); + + ceph_con_init(&s->s_con, s, &mds_con_ops, &mdsc->fsc->client->msgr); + + spin_lock_init(&s->s_gen_ttl_lock); + s->s_cap_gen = 1; + s->s_cap_ttl = jiffies - 1; + + spin_lock_init(&s->s_cap_lock); + s->s_renew_requested = 0; + s->s_renew_seq = 0; + INIT_LIST_HEAD(&s->s_caps); + s->s_nr_caps = 0; + refcount_set(&s->s_ref, 1); + INIT_LIST_HEAD(&s->s_waiting); + INIT_LIST_HEAD(&s->s_unsafe); + xa_init(&s->s_delegated_inos); + s->s_num_cap_releases = 0; + s->s_cap_reconnect = 0; + s->s_cap_iterator = NULL; + INIT_LIST_HEAD(&s->s_cap_releases); + INIT_WORK(&s->s_cap_release_work, ceph_cap_release_work); + + INIT_LIST_HEAD(&s->s_cap_dirty); + INIT_LIST_HEAD(&s->s_cap_flushing); + + mdsc->sessions[mds] = s; + atomic_inc(&mdsc->num_sessions); + refcount_inc(&s->s_ref); /* one ref to sessions[], one to caller */ + + ceph_con_open(&s->s_con, CEPH_ENTITY_TYPE_MDS, mds, + ceph_mdsmap_get_addr(mdsc->mdsmap, mds)); + + return s; + +fail_realloc: + kfree(s); + return ERR_PTR(-ENOMEM); +} + +/* + * called under mdsc->mutex + */ +static void __unregister_session(struct ceph_mds_client *mdsc, + struct ceph_mds_session *s) +{ + dout("__unregister_session mds%d %p\n", s->s_mds, s); + BUG_ON(mdsc->sessions[s->s_mds] != s); + mdsc->sessions[s->s_mds] = NULL; + 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_iterate_sessions(struct ceph_mds_client *mdsc, + void (*cb)(struct ceph_mds_session *), + bool check_state) +{ + int mds; + + mutex_lock(&mdsc->mutex); + for (mds = 0; mds < mdsc->max_sessions; ++mds) { + struct ceph_mds_session *s; + + s = __ceph_lookup_mds_session(mdsc, mds); + if (!s) + continue; + + if (check_state && !check_session_state(s)) { + ceph_put_mds_session(s); + continue; + } + + mutex_unlock(&mdsc->mutex); + cb(s); + ceph_put_mds_session(s); + mutex_lock(&mdsc->mutex); + } + mutex_unlock(&mdsc->mutex); +} + +void ceph_mdsc_release_request(struct kref *kref) +{ + struct ceph_mds_request *req = container_of(kref, + struct ceph_mds_request, + r_kref); + ceph_mdsc_release_dir_caps_no_check(req); + 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); + /* avoid calling iput_final() in mds dispatch threads */ + ceph_async_iput(req->r_inode); + } + if (req->r_parent) { + ceph_put_cap_refs(ceph_inode(req->r_parent), CEPH_CAP_PIN); + ceph_async_iput(req->r_parent); + } + ceph_async_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); + ceph_async_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); + WARN_ON_ONCE(!list_empty(&req->r_wait)); + kmem_cache_free(ceph_mds_request_cachep, req); +} + +DEFINE_RB_FUNCS(request, struct ceph_mds_request, r_tid, r_node) + +/* + * lookup session, bump ref if found. + * + * called under mdsc->mutex. + */ +static struct ceph_mds_request * +lookup_get_request(struct ceph_mds_client *mdsc, u64 tid) +{ + struct ceph_mds_request *req; + + req = lookup_request(&mdsc->request_tree, tid); + if (req) + ceph_mdsc_get_request(req); + + return req; +} + +/* + * Register an in-flight request, and assign a tid. Link to directory + * are modifying (if any). + * + * Called under mdsc->mutex. + */ +static void __register_request(struct ceph_mds_client *mdsc, + struct ceph_mds_request *req, + struct inode *dir) +{ + int ret = 0; + + req->r_tid = ++mdsc->last_tid; + if (req->r_num_caps) { + ret = ceph_reserve_caps(mdsc, &req->r_caps_reservation, + req->r_num_caps); + if (ret < 0) { + pr_err("__register_request %p " + "failed to reserve caps: %d\n", req, ret); + /* set req->r_err to fail early from __do_request */ + req->r_err = ret; + return; + } + } + dout("__register_request %p tid %lld\n", req, req->r_tid); + ceph_mdsc_get_request(req); + insert_request(&mdsc->request_tree, req); + + req->r_uid = current_fsuid(); + req->r_gid = current_fsgid(); + + if (mdsc->oldest_tid == 0 && req->r_op != CEPH_MDS_OP_SETFILELOCK) + mdsc->oldest_tid = req->r_tid; + + if (dir) { + struct ceph_inode_info *ci = ceph_inode(dir); + + ihold(dir); + req->r_unsafe_dir = dir; + spin_lock(&ci->i_unsafe_lock); + list_add_tail(&req->r_unsafe_dir_item, &ci->i_unsafe_dirops); + spin_unlock(&ci->i_unsafe_lock); + } +} + +static void __unregister_request(struct ceph_mds_client *mdsc, + struct ceph_mds_request *req) +{ + dout("__unregister_request %p tid %lld\n", req, req->r_tid); + + /* Never leave an unregistered request on an unsafe list! */ + list_del_init(&req->r_unsafe_item); + + if (req->r_tid == mdsc->oldest_tid) { + struct rb_node *p = rb_next(&req->r_node); + mdsc->oldest_tid = 0; + while (p) { + struct ceph_mds_request *next_req = + rb_entry(p, struct ceph_mds_request, r_node); + if (next_req->r_op != CEPH_MDS_OP_SETFILELOCK) { + mdsc->oldest_tid = next_req->r_tid; + break; + } + p = rb_next(p); + } + } + + erase_request(&mdsc->request_tree, req); + + if (req->r_unsafe_dir) { + struct ceph_inode_info *ci = ceph_inode(req->r_unsafe_dir); + spin_lock(&ci->i_unsafe_lock); + list_del_init(&req->r_unsafe_dir_item); + spin_unlock(&ci->i_unsafe_lock); + } + if (req->r_target_inode && + test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) { + struct ceph_inode_info *ci = ceph_inode(req->r_target_inode); + spin_lock(&ci->i_unsafe_lock); + list_del_init(&req->r_unsafe_target_item); + spin_unlock(&ci->i_unsafe_lock); + } + + if (req->r_unsafe_dir) { + /* avoid calling iput_final() in mds dispatch threads */ + ceph_async_iput(req->r_unsafe_dir); + req->r_unsafe_dir = NULL; + } + + complete_all(&req->r_safe_completion); + + ceph_mdsc_put_request(req); +} + +/* + * Walk back up the dentry tree until we hit a dentry representing a + * non-snapshot inode. We do this using the rcu_read_lock (which must be held + * when calling this) to ensure that the objects won't disappear while we're + * working with them. Once we hit a candidate dentry, we attempt to take a + * reference to it, and return that as the result. + */ +static struct inode *get_nonsnap_parent(struct dentry *dentry) +{ + struct inode *inode = NULL; + + while (dentry && !IS_ROOT(dentry)) { + inode = d_inode_rcu(dentry); + if (!inode || ceph_snap(inode) == CEPH_NOSNAP) + break; + dentry = dentry->d_parent; + } + if (inode) + inode = igrab(inode); + return inode; +} + +/* + * Choose mds to send request to next. If there is a hint set in the + * request (e.g., due to a prior forward hint from the mds), use that. + * Otherwise, consult frag tree and/or caps to identify the + * appropriate mds. If all else fails, choose randomly. + * + * Called under mdsc->mutex. + */ +static int __choose_mds(struct ceph_mds_client *mdsc, + struct ceph_mds_request *req, + bool *random) +{ + struct inode *inode; + struct ceph_inode_info *ci; + struct ceph_cap *cap; + int mode = req->r_direct_mode; + int mds = -1; + u32 hash = req->r_direct_hash; + bool is_hash = test_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags); + + if (random) + *random = false; + + /* + * 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("%s using resend_mds mds%d\n", __func__, + req->r_resend_mds); + return req->r_resend_mds; + } + + if (mode == USE_RANDOM_MDS) + goto random; + + inode = NULL; + if (req->r_inode) { + if (ceph_snap(req->r_inode) != CEPH_SNAPDIR) { + inode = req->r_inode; + ihold(inode); + } else { + /* req->r_dentry is non-null for LSSNAP request */ + rcu_read_lock(); + inode = get_nonsnap_parent(req->r_dentry); + rcu_read_unlock(); + dout("%s using snapdir's parent %p\n", __func__, inode); + } + } else if (req->r_dentry) { + /* ignore race with rename; old or new d_parent is okay */ + struct dentry *parent; + struct inode *dir; + + rcu_read_lock(); + parent = READ_ONCE(req->r_dentry->d_parent); + dir = req->r_parent ? : d_inode_rcu(parent); + + if (!dir || dir->i_sb != mdsc->fsc->sb) { + /* not this fs or parent went negative */ + inode = d_inode(req->r_dentry); + if (inode) + ihold(inode); + } else if (ceph_snap(dir) != CEPH_NOSNAP) { + /* direct snapped/virtual snapdir requests + * based on parent dir inode */ + inode = get_nonsnap_parent(parent); + dout("%s using nonsnap parent %p\n", __func__, inode); + } else { + /* dentry target */ + inode = d_inode(req->r_dentry); + if (!inode || mode == USE_AUTH_MDS) { + /* dir + name */ + inode = igrab(dir); + hash = ceph_dentry_hash(dir, req->r_dentry); + is_hash = true; + } else { + ihold(inode); + } + } + rcu_read_unlock(); + } + + dout("%s %p is_hash=%d (0x%x) mode %d\n", __func__, inode, (int)is_hash, + 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("%s %p %llx.%llx frag %u mds%d (%d/%d)\n", + __func__, inode, ceph_vinop(inode), + frag.frag, mds, (int)r, frag.ndist); + if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >= + CEPH_MDS_STATE_ACTIVE && + !ceph_mdsmap_is_laggy(mdsc->mdsmap, mds)) + goto out; + } + + /* since this file/dir wasn't known to be + * replicated, then we want to look for the + * authoritative mds. */ + if (frag.mds >= 0) { + /* choose auth mds */ + mds = frag.mds; + dout("%s %p %llx.%llx frag %u mds%d (auth)\n", + __func__, inode, ceph_vinop(inode), + frag.frag, mds); + if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >= + CEPH_MDS_STATE_ACTIVE) { + if (!ceph_mdsmap_is_laggy(mdsc->mdsmap, + mds)) + goto out; + } + } + mode = USE_AUTH_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); + ceph_async_iput(inode); + goto random; + } + mds = cap->session->s_mds; + dout("%s %p %llx.%llx mds%d (%scap %p)\n", __func__, + inode, ceph_vinop(inode), mds, + cap == ci->i_auth_cap ? "auth " : "", cap); + spin_unlock(&ci->i_ceph_lock); +out: + /* avoid calling iput_final() while holding mdsc->mutex or + * in mds dispatch threads */ + ceph_async_iput(inode); + return mds; + +random: + if (random) + *random = true; + + mds = ceph_mdsmap_get_random_mds(mdsc->mdsmap); + dout("%s chose random mds%d\n", __func__, mds); + return mds; +} + + +/* + * session messages + */ +struct ceph_msg *ceph_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("ENOMEM creating session %s msg\n", + ceph_session_op_name(op)); + return NULL; + } + h = msg->front.iov_base; + h->op = cpu_to_le32(op); + h->seq = cpu_to_le64(seq); + + return msg; +} + +static const unsigned char feature_bits[] = CEPHFS_FEATURES_CLIENT_SUPPORTED; +#define FEATURE_BYTES(c) (DIV_ROUND_UP((size_t)feature_bits[c - 1] + 1, 64) * 8) +static int encode_supported_features(void **p, void *end) +{ + static const size_t count = ARRAY_SIZE(feature_bits); + + if (count > 0) { + size_t i; + size_t size = FEATURE_BYTES(count); + unsigned long bit; + + if (WARN_ON_ONCE(*p + 4 + size > end)) + return -ERANGE; + + ceph_encode_32(p, size); + memset(*p, 0, size); + for (i = 0; i < count; i++) { + bit = feature_bits[i]; + ((unsigned char *)(*p))[bit / 8] |= BIT(bit % 8); + } + *p += size; + } else { + if (WARN_ON_ONCE(*p + 4 > end)) + return -ERANGE; + + ceph_encode_32(p, 0); + } + + return 0; +} + +static const unsigned char metric_bits[] = CEPHFS_METRIC_SPEC_CLIENT_SUPPORTED; +#define METRIC_BYTES(cnt) (DIV_ROUND_UP((size_t)metric_bits[cnt - 1] + 1, 64) * 8) +static int encode_metric_spec(void **p, void *end) +{ + static const size_t count = ARRAY_SIZE(metric_bits); + + /* header */ + if (WARN_ON_ONCE(*p + 2 > end)) + return -ERANGE; + + ceph_encode_8(p, 1); /* version */ + ceph_encode_8(p, 1); /* compat */ + + if (count > 0) { + size_t i; + size_t size = METRIC_BYTES(count); + + if (WARN_ON_ONCE(*p + 4 + 4 + size > end)) + return -ERANGE; + + /* metric spec info length */ + ceph_encode_32(p, 4 + size); + + /* metric spec */ + ceph_encode_32(p, size); + memset(*p, 0, size); + for (i = 0; i < count; i++) + ((unsigned char *)(*p))[i / 8] |= BIT(metric_bits[i] % 8); + *p += size; + } else { + if (WARN_ON_ONCE(*p + 4 + 4 > end)) + return -ERANGE; + + /* metric spec info length */ + ceph_encode_32(p, 4); + /* metric spec */ + ceph_encode_32(p, 0); + } + + return 0; +} + +/* + * session message, specialization for CEPH_SESSION_REQUEST_OPEN + * to include additional client metadata fields. + */ +static struct ceph_msg *create_session_open_msg(struct ceph_mds_client *mdsc, u64 seq) +{ + struct ceph_msg *msg; + struct ceph_mds_session_head *h; + int i = -1; + int extra_bytes = 0; + int metadata_key_count = 0; + struct ceph_options *opt = mdsc->fsc->client->options; + struct ceph_mount_options *fsopt = mdsc->fsc->mount_options; + size_t size, count; + void *p, *end; + int ret; + + const char* metadata[][2] = { + {"hostname", mdsc->nodename}, + {"kernel_version", init_utsname()->release}, + {"entity_id", opt->name ? : ""}, + {"root", fsopt->server_path ? : "/"}, + {NULL, NULL} + }; + + /* Calculate serialized length of metadata */ + extra_bytes = 4; /* map length */ + for (i = 0; metadata[i][0]; ++i) { + extra_bytes += 8 + strlen(metadata[i][0]) + + strlen(metadata[i][1]); + metadata_key_count++; + } + + /* supported feature */ + size = 0; + count = ARRAY_SIZE(feature_bits); + if (count > 0) + size = FEATURE_BYTES(count); + extra_bytes += 4 + size; + + /* metric spec */ + size = 0; + count = ARRAY_SIZE(metric_bits); + if (count > 0) + size = METRIC_BYTES(count); + extra_bytes += 2 + 4 + 4 + size; + + /* Allocate the message */ + msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h) + extra_bytes, + GFP_NOFS, false); + if (!msg) { + pr_err("ENOMEM creating session open msg\n"); + return ERR_PTR(-ENOMEM); + } + p = msg->front.iov_base; + end = p + msg->front.iov_len; + + h = p; + h->op = cpu_to_le32(CEPH_SESSION_REQUEST_OPEN); + h->seq = cpu_to_le64(seq); + + /* + * Serialize client metadata into waiting buffer space, using + * the format that userspace expects for map<string, string> + * + * ClientSession messages with metadata are v4 + */ + msg->hdr.version = cpu_to_le16(4); + msg->hdr.compat_version = cpu_to_le16(1); + + /* The write pointer, following the session_head structure */ + p += sizeof(*h); + + /* Number of entries in the map */ + ceph_encode_32(&p, metadata_key_count); + + /* Two length-prefixed strings for each entry in the map */ + for (i = 0; metadata[i][0]; ++i) { + size_t const key_len = strlen(metadata[i][0]); + size_t const val_len = strlen(metadata[i][1]); + + ceph_encode_32(&p, key_len); + memcpy(p, metadata[i][0], key_len); + p += key_len; + ceph_encode_32(&p, val_len); + memcpy(p, metadata[i][1], val_len); + p += val_len; + } + + ret = encode_supported_features(&p, end); + if (ret) { + pr_err("encode_supported_features failed!\n"); + ceph_msg_put(msg); + return ERR_PTR(ret); + } + + ret = encode_metric_spec(&p, end); + if (ret) { + pr_err("encode_metric_spec failed!\n"); + ceph_msg_put(msg); + return ERR_PTR(ret); + } + + msg->front.iov_len = p - msg->front.iov_base; + msg->hdr.front_len = cpu_to_le32(msg->front.iov_len); + + return msg; +} + +/* + * send session open request. + * + * called under mdsc->mutex + */ +static int __open_session(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session) +{ + struct ceph_msg *msg; + int mstate; + int mds = session->s_mds; + + /* wait for mds to go active? */ + mstate = ceph_mdsmap_get_state(mdsc->mdsmap, mds); + dout("open_session to mds%d (%s)\n", mds, + ceph_mds_state_name(mstate)); + session->s_state = CEPH_MDS_SESSION_OPENING; + session->s_renew_requested = jiffies; + + /* send connect message */ + msg = create_session_open_msg(mdsc, session->s_seq); + if (IS_ERR(msg)) + return PTR_ERR(msg); + 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; + int ret; + + 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) { + ret = __open_session(mdsc, session); + if (ret) + return ERR_PTR(ret); + } + + 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->possible_max_rank) + 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]); + ceph_put_mds_session(ts); + } +} + +void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session) +{ + mutex_lock(&mdsc->mutex); + __open_export_target_sessions(mdsc, session); + mutex_unlock(&mdsc->mutex); +} + +/* + * session caps + */ + +static void detach_cap_releases(struct ceph_mds_session *session, + struct list_head *target) +{ + lockdep_assert_held(&session->s_cap_lock); + + list_splice_init(&session->s_cap_releases, target); + session->s_num_cap_releases = 0; + dout("dispose_cap_releases mds%d\n", session->s_mds); +} + +static void dispose_cap_releases(struct ceph_mds_client *mdsc, + struct list_head *dispose) +{ + while (!list_empty(dispose)) { + struct ceph_cap *cap; + /* zero out the in-progress message */ + cap = list_first_entry(dispose, struct ceph_cap, session_caps); + list_del(&cap->session_caps); + ceph_put_cap(mdsc, cap); + } +} + +static void cleanup_session_requests(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session) +{ + struct ceph_mds_request *req; + struct rb_node *p; + + dout("cleanup_session_requests mds%d\n", session->s_mds); + mutex_lock(&mdsc->mutex); + while (!list_empty(&session->s_unsafe)) { + req = list_first_entry(&session->s_unsafe, + struct ceph_mds_request, r_unsafe_item); + pr_warn_ratelimited(" dropping unsafe request %llu\n", + req->r_tid); + if (req->r_target_inode) + mapping_set_error(req->r_target_inode->i_mapping, -EIO); + if (req->r_unsafe_dir) + mapping_set_error(req->r_unsafe_dir->i_mapping, -EIO); + __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. + */ +int ceph_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) { + /* avoid calling iput_final() while holding + * s_mutex or in mds dispatch threads */ + ceph_async_iput(last_inode); + last_inode = NULL; + } + if (old_cap) { + ceph_put_cap(session->s_mdsc, old_cap); + old_cap = NULL; + } + + ret = cb(inode, cap, arg); + last_inode = inode; + + spin_lock(&session->s_cap_lock); + p = p->next; + if (!cap->ci) { + dout("iterate_session_caps finishing cap %p removal\n", + cap); + BUG_ON(cap->session != session); + cap->session = NULL; + list_del_init(&cap->session_caps); + session->s_nr_caps--; + atomic64_dec(&session->s_mdsc->metric.total_caps); + if (cap->queue_release) + __ceph_queue_cap_release(session, cap); + else + old_cap = cap; /* put_cap it w/o locks held */ + } + if (ret < 0) + goto out; + } + ret = 0; +out: + session->s_cap_iterator = NULL; + spin_unlock(&session->s_cap_lock); + + ceph_async_iput(last_inode); + if (old_cap) + ceph_put_cap(session->s_mdsc, old_cap); + + return ret; +} + +static int remove_capsnaps(struct ceph_mds_client *mdsc, struct inode *inode) +{ + struct ceph_inode_info *ci = ceph_inode(inode); + struct ceph_cap_snap *capsnap; + int capsnap_release = 0; + + lockdep_assert_held(&ci->i_ceph_lock); + + dout("removing capsnaps, ci is %p, inode is %p\n", ci, inode); + + while (!list_empty(&ci->i_cap_snaps)) { + capsnap = list_first_entry(&ci->i_cap_snaps, + struct ceph_cap_snap, ci_item); + __ceph_remove_capsnap(inode, capsnap, NULL, NULL); + ceph_put_snap_context(capsnap->context); + ceph_put_cap_snap(capsnap); + capsnap_release++; + } + wake_up_all(&ci->i_cap_wq); + wake_up_all(&mdsc->cap_flushing_wq); + return capsnap_release; +} + +static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap, + void *arg) +{ + struct ceph_fs_client *fsc = (struct ceph_fs_client *)arg; + struct ceph_mds_client *mdsc = fsc->mdsc; + struct ceph_inode_info *ci = ceph_inode(inode); + LIST_HEAD(to_remove); + bool dirty_dropped = false; + bool invalidate = false; + int capsnap_release = 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_cap_flush *cf; + + if (READ_ONCE(fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) { + if (inode->i_data.nrpages > 0) + invalidate = true; + if (ci->i_wrbuffer_ref > 0) + mapping_set_error(&inode->i_data, -EIO); + } + + while (!list_empty(&ci->i_cap_flush_list)) { + cf = list_first_entry(&ci->i_cap_flush_list, + struct ceph_cap_flush, i_list); + list_move(&cf->i_list, &to_remove); + } + + spin_lock(&mdsc->cap_dirty_lock); + + list_for_each_entry(cf, &to_remove, i_list) + list_del_init(&cf->g_list); + + if (!list_empty(&ci->i_dirty_item)) { + pr_warn_ratelimited( + " dropping dirty %s state for %p %lld\n", + ceph_cap_string(ci->i_dirty_caps), + inode, ceph_ino(inode)); + ci->i_dirty_caps = 0; + list_del_init(&ci->i_dirty_item); + dirty_dropped = true; + } + if (!list_empty(&ci->i_flushing_item)) { + pr_warn_ratelimited( + " dropping dirty+flushing %s state for %p %lld\n", + ceph_cap_string(ci->i_flushing_caps), + inode, ceph_ino(inode)); + ci->i_flushing_caps = 0; + list_del_init(&ci->i_flushing_item); + mdsc->num_cap_flushing--; + dirty_dropped = true; + } + spin_unlock(&mdsc->cap_dirty_lock); + + if (dirty_dropped) { + mapping_set_error(inode->i_mapping, -EIO); + + if (ci->i_wrbuffer_ref_head == 0 && + ci->i_wr_ref == 0 && + ci->i_dirty_caps == 0 && + ci->i_flushing_caps == 0) { + ceph_put_snap_context(ci->i_head_snapc); + ci->i_head_snapc = NULL; + } + } + + if (atomic_read(&ci->i_filelock_ref) > 0) { + /* make further file lock syscall return -EIO */ + ci->i_ceph_flags |= CEPH_I_ERROR_FILELOCK; + pr_warn_ratelimited(" dropping file locks for %p %lld\n", + inode, ceph_ino(inode)); + } + + if (!ci->i_dirty_caps && ci->i_prealloc_cap_flush) { + list_add(&ci->i_prealloc_cap_flush->i_list, &to_remove); + ci->i_prealloc_cap_flush = NULL; + } + + if (!list_empty(&ci->i_cap_snaps)) + capsnap_release = remove_capsnaps(mdsc, inode); + } + spin_unlock(&ci->i_ceph_lock); + while (!list_empty(&to_remove)) { + struct ceph_cap_flush *cf; + cf = list_first_entry(&to_remove, + struct ceph_cap_flush, i_list); + list_del_init(&cf->i_list); + if (!cf->is_capsnap) + ceph_free_cap_flush(cf); + } + + wake_up_all(&ci->i_cap_wq); + if (invalidate) + ceph_queue_invalidate(inode); + if (dirty_dropped) + iput(inode); + while (capsnap_release--) + iput(inode); + return 0; +} + +/* + * caller must hold session s_mutex + */ +static void remove_session_caps(struct ceph_mds_session *session) +{ + struct ceph_fs_client *fsc = session->s_mdsc->fsc; + struct super_block *sb = fsc->sb; + LIST_HEAD(dispose); + + dout("remove_session_caps on %p\n", session); + ceph_iterate_session_caps(session, remove_session_caps_cb, fsc); + + wake_up_all(&fsc->mdsc->cap_flushing_wq); + + spin_lock(&session->s_cap_lock); + if (session->s_nr_caps > 0) { + struct inode *inode; + struct ceph_cap *cap, *prev = NULL; + struct ceph_vino vino; + /* + * iterate_session_caps() skips inodes that are being + * deleted, we need to wait until deletions are complete. + * __wait_on_freeing_inode() is designed for the job, + * but it is not exported, so use lookup inode function + * to access it. + */ + while (!list_empty(&session->s_caps)) { + cap = list_entry(session->s_caps.next, + struct ceph_cap, session_caps); + if (cap == prev) + break; + prev = cap; + vino = cap->ci->i_vino; + spin_unlock(&session->s_cap_lock); + + inode = ceph_find_inode(sb, vino); + /* avoid calling iput_final() while holding s_mutex */ + ceph_async_iput(inode); + + spin_lock(&session->s_cap_lock); + } + } + + // drop cap expires and unlock s_cap_lock + detach_cap_releases(session, &dispose); + + BUG_ON(session->s_nr_caps > 0); + BUG_ON(!list_empty(&session->s_cap_flushing)); + spin_unlock(&session->s_cap_lock); + dispose_cap_releases(session->s_mdsc, &dispose); +} + +enum { + RECONNECT, + RENEWCAPS, + FORCE_RO, +}; + +/* + * wake up any threads waiting on this session's caps. if the cap is + * old (didn't get renewed on the client reconnect), remove it now. + * + * caller must hold s_mutex. + */ +static int wake_up_session_cb(struct inode *inode, struct ceph_cap *cap, + void *arg) +{ + struct ceph_inode_info *ci = ceph_inode(inode); + unsigned long ev = (unsigned long)arg; + + if (ev == RECONNECT) { + spin_lock(&ci->i_ceph_lock); + ci->i_wanted_max_size = 0; + ci->i_requested_max_size = 0; + spin_unlock(&ci->i_ceph_lock); + } else if (ev == RENEWCAPS) { + if (cap->cap_gen < cap->session->s_cap_gen) { + /* mds did not re-issue stale cap */ + spin_lock(&ci->i_ceph_lock); + cap->issued = cap->implemented = CEPH_CAP_PIN; + spin_unlock(&ci->i_ceph_lock); + } + } else if (ev == FORCE_RO) { + } + wake_up_all(&ci->i_cap_wq); + return 0; +} + +static void wake_up_session_caps(struct ceph_mds_session *session, int ev) +{ + dout("wake_up_session_caps %p mds%d\n", session, session->s_mds); + ceph_iterate_session_caps(session, wake_up_session_cb, + (void *)(unsigned long)ev); +} + +/* + * Send periodic message to MDS renewing all currently held caps. The + * ack will reset the expiration for all caps from this session. + * + * caller holds s_mutex + */ +static int send_renew_caps(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session) +{ + struct ceph_msg *msg; + int state; + + if (time_after_eq(jiffies, session->s_cap_ttl) && + time_after_eq(session->s_cap_ttl, session->s_renew_requested)) + pr_info("mds%d caps stale\n", session->s_mds); + session->s_renew_requested = jiffies; + + /* do not try to renew caps until a recovering mds has reconnected + * with its clients. */ + state = ceph_mdsmap_get_state(mdsc->mdsmap, session->s_mds); + if (state < CEPH_MDS_STATE_RECONNECT) { + dout("send_renew_caps ignoring mds%d (%s)\n", + session->s_mds, ceph_mds_state_name(state)); + return 0; + } + + dout("send_renew_caps to mds%d (%s)\n", session->s_mds, + ceph_mds_state_name(state)); + msg = ceph_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 = ceph_create_session_msg(CEPH_SESSION_FLUSHMSG_ACK, seq); + if (!msg) + return -ENOMEM; + ceph_con_send(&session->s_con, msg); + return 0; +} + + +/* + * Note new cap ttl, and any transition from stale -> not stale (fresh?). + * + * Called under session->s_mutex + */ +static void renewed_caps(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session, int is_renew) +{ + int was_stale; + int wake = 0; + + spin_lock(&session->s_cap_lock); + was_stale = is_renew && time_after_eq(jiffies, session->s_cap_ttl); + + session->s_cap_ttl = session->s_renew_requested + + mdsc->mdsmap->m_session_timeout*HZ; + + if (was_stale) { + if (time_before(jiffies, session->s_cap_ttl)) { + pr_info("mds%d caps renewed\n", session->s_mds); + wake = 1; + } else { + pr_info("mds%d caps still stale\n", session->s_mds); + } + } + dout("renewed_caps mds%d ttl now %lu, was %s, now %s\n", + session->s_mds, session->s_cap_ttl, was_stale ? "stale" : "fresh", + time_before(jiffies, session->s_cap_ttl) ? "stale" : "fresh"); + spin_unlock(&session->s_cap_lock); + + if (wake) + wake_up_session_caps(session, RENEWCAPS); +} + +/* + * send a session close request + */ +static int request_close_session(struct ceph_mds_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 = ceph_create_session_msg(CEPH_SESSION_REQUEST_CLOSE, + session->s_seq); + if (!msg) + return -ENOMEM; + ceph_con_send(&session->s_con, msg); + return 1; +} + +/* + * Called with s_mutex held. + */ +static int __close_session(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session) +{ + if (session->s_state >= CEPH_MDS_SESSION_CLOSING) + return 0; + session->s_state = CEPH_MDS_SESSION_CLOSING; + return request_close_session(session); +} + +static bool drop_negative_children(struct dentry *dentry) +{ + struct dentry *child; + bool all_negative = true; + + if (!d_is_dir(dentry)) + goto out; + + spin_lock(&dentry->d_lock); + list_for_each_entry(child, &dentry->d_subdirs, d_child) { + if (d_really_is_positive(child)) { + all_negative = false; + break; + } + } + spin_unlock(&dentry->d_lock); + + if (all_negative) + shrink_dcache_parent(dentry); +out: + return all_negative; +} + +/* + * Trim old(er) caps. + * + * Because we can't cache an inode without one or more caps, we do + * this indirectly: if a cap is unused, we prune its aliases, at which + * point the inode will hopefully get dropped to. + * + * Yes, this is a bit sloppy. Our only real goal here is to respond to + * memory pressure from the MDS, though, so it needn't be perfect. + */ +static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg) +{ + int *remaining = arg; + struct ceph_inode_info *ci = ceph_inode(inode); + int used, wanted, oissued, mine; + + if (*remaining <= 0) + return -1; + + spin_lock(&ci->i_ceph_lock); + mine = cap->issued | cap->implemented; + used = __ceph_caps_used(ci); + wanted = __ceph_caps_file_wanted(ci); + oissued = __ceph_caps_issued_other(ci, cap); + + dout("trim_caps_cb %p cap %p mine %s oissued %s used %s wanted %s\n", + inode, cap, ceph_cap_string(mine), ceph_cap_string(oissued), + ceph_cap_string(used), ceph_cap_string(wanted)); + if (cap == ci->i_auth_cap) { + if (ci->i_dirty_caps || ci->i_flushing_caps || + !list_empty(&ci->i_cap_snaps)) + goto out; + if ((used | wanted) & CEPH_CAP_ANY_WR) + goto out; + /* Note: it's possible that i_filelock_ref becomes non-zero + * after dropping auth caps. It doesn't hurt because reply + * of lock mds request will re-add auth caps. */ + if (atomic_read(&ci->i_filelock_ref) > 0) + goto out; + } + /* The inode has cached pages, but it's no longer used. + * we can safely drop it */ + if (S_ISREG(inode->i_mode) && + wanted == 0 && used == CEPH_CAP_FILE_CACHE && + !(oissued & CEPH_CAP_FILE_CACHE)) { + used = 0; + oissued = 0; + } + if ((used | wanted) & ~oissued & mine) + goto out; /* we need these caps */ + + if (oissued) { + /* we aren't the only cap.. just remove us */ + __ceph_remove_cap(cap, true); + (*remaining)--; + } else { + struct dentry *dentry; + /* try dropping referring dentries */ + spin_unlock(&ci->i_ceph_lock); + dentry = d_find_any_alias(inode); + if (dentry && drop_negative_children(dentry)) { + int count; + dput(dentry); + d_prune_aliases(inode); + count = atomic_read(&inode->i_count); + if (count == 1) + (*remaining)--; + dout("trim_caps_cb %p cap %p pruned, count now %d\n", + inode, cap, count); + } else { + dput(dentry); + } + return 0; + } + +out: + spin_unlock(&ci->i_ceph_lock); + return 0; +} + +/* + * Trim session cap count down to some max number. + */ +int ceph_trim_caps(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session, + int max_caps) +{ + int trim_caps = session->s_nr_caps - max_caps; + + dout("trim_caps mds%d start: %d / %d, trim %d\n", + session->s_mds, session->s_nr_caps, max_caps, trim_caps); + if (trim_caps > 0) { + int remaining = trim_caps; + + ceph_iterate_session_caps(session, trim_caps_cb, &remaining); + dout("trim_caps mds%d done: %d / %d, trimmed %d\n", + session->s_mds, session->s_nr_caps, max_caps, + trim_caps - remaining); + } + + ceph_flush_cap_releases(mdsc, session); + return 0; +} + +static int check_caps_flush(struct ceph_mds_client *mdsc, + u64 want_flush_tid) +{ + int ret = 1; + + spin_lock(&mdsc->cap_dirty_lock); + if (!list_empty(&mdsc->cap_flush_list)) { + struct ceph_cap_flush *cf = + list_first_entry(&mdsc->cap_flush_list, + struct ceph_cap_flush, g_list); + if (cf->tid <= want_flush_tid) { + dout("check_caps_flush still flushing tid " + "%llu <= %llu\n", cf->tid, want_flush_tid); + ret = 0; + } + } + spin_unlock(&mdsc->cap_dirty_lock); + return ret; +} + +/* + * flush all dirty inode data to disk. + * + * returns true if we've flushed through want_flush_tid + */ +static void wait_caps_flush(struct ceph_mds_client *mdsc, + u64 want_flush_tid) +{ + dout("check_caps_flush want %llu\n", want_flush_tid); + + wait_event(mdsc->cap_flushing_wq, + check_caps_flush(mdsc, want_flush_tid)); + + dout("check_caps_flush ok, flushed thru %llu\n", want_flush_tid); +} + +/* + * called under s_mutex + */ +static void ceph_send_cap_releases(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session) +{ + struct ceph_msg *msg = NULL; + struct ceph_mds_cap_release *head; + struct ceph_mds_cap_item *item; + struct ceph_osd_client *osdc = &mdsc->fsc->client->osdc; + struct ceph_cap *cap; + LIST_HEAD(tmp_list); + int num_cap_releases; + __le32 barrier, *cap_barrier; + + down_read(&osdc->lock); + barrier = cpu_to_le32(osdc->epoch_barrier); + up_read(&osdc->lock); + + spin_lock(&session->s_cap_lock); +again: + list_splice_init(&session->s_cap_releases, &tmp_list); + num_cap_releases = session->s_num_cap_releases; + session->s_num_cap_releases = 0; + spin_unlock(&session->s_cap_lock); + + while (!list_empty(&tmp_list)) { + if (!msg) { + msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPRELEASE, + PAGE_SIZE, GFP_NOFS, false); + if (!msg) + goto out_err; + head = msg->front.iov_base; + head->num = cpu_to_le32(0); + msg->front.iov_len = sizeof(*head); + + msg->hdr.version = cpu_to_le16(2); + msg->hdr.compat_version = cpu_to_le16(1); + } + + cap = list_first_entry(&tmp_list, struct ceph_cap, + session_caps); + list_del(&cap->session_caps); + num_cap_releases--; + + head = msg->front.iov_base; + put_unaligned_le32(get_unaligned_le32(&head->num) + 1, + &head->num); + item = msg->front.iov_base + msg->front.iov_len; + item->ino = cpu_to_le64(cap->cap_ino); + item->cap_id = cpu_to_le64(cap->cap_id); + item->migrate_seq = cpu_to_le32(cap->mseq); + item->seq = cpu_to_le32(cap->issue_seq); + msg->front.iov_len += sizeof(*item); + + ceph_put_cap(mdsc, cap); + + if (le32_to_cpu(head->num) == CEPH_CAPS_PER_RELEASE) { + // Append cap_barrier field + cap_barrier = msg->front.iov_base + msg->front.iov_len; + *cap_barrier = barrier; + msg->front.iov_len += sizeof(*cap_barrier); + + msg->hdr.front_len = cpu_to_le32(msg->front.iov_len); + dout("send_cap_releases mds%d %p\n", session->s_mds, msg); + ceph_con_send(&session->s_con, msg); + msg = NULL; + } + } + + BUG_ON(num_cap_releases != 0); + + spin_lock(&session->s_cap_lock); + if (!list_empty(&session->s_cap_releases)) + goto again; + spin_unlock(&session->s_cap_lock); + + if (msg) { + // Append cap_barrier field + cap_barrier = msg->front.iov_base + msg->front.iov_len; + *cap_barrier = barrier; + msg->front.iov_len += sizeof(*cap_barrier); + + msg->hdr.front_len = cpu_to_le32(msg->front.iov_len); + dout("send_cap_releases mds%d %p\n", session->s_mds, msg); + ceph_con_send(&session->s_con, msg); + } + return; +out_err: + pr_err("send_cap_releases mds%d, failed to allocate message\n", + session->s_mds); + spin_lock(&session->s_cap_lock); + list_splice(&tmp_list, &session->s_cap_releases); + session->s_num_cap_releases += num_cap_releases; + spin_unlock(&session->s_cap_lock); +} + +static void ceph_cap_release_work(struct work_struct *work) +{ + struct ceph_mds_session *session = + container_of(work, struct ceph_mds_session, s_cap_release_work); + + mutex_lock(&session->s_mutex); + if (session->s_state == CEPH_MDS_SESSION_OPEN || + session->s_state == CEPH_MDS_SESSION_HUNG) + ceph_send_cap_releases(session->s_mdsc, session); + mutex_unlock(&session->s_mutex); + ceph_put_mds_session(session); +} + +void ceph_flush_cap_releases(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session) +{ + if (mdsc->stopping) + return; + + ceph_get_mds_session(session); + if (queue_work(mdsc->fsc->cap_wq, + &session->s_cap_release_work)) { + dout("cap release work queued\n"); + } else { + ceph_put_mds_session(session); + dout("failed to queue cap release work\n"); + } +} + +/* + * caller holds session->s_cap_lock + */ +void __ceph_queue_cap_release(struct ceph_mds_session *session, + struct ceph_cap *cap) +{ + list_add_tail(&cap->session_caps, &session->s_cap_releases); + session->s_num_cap_releases++; + + if (!(session->s_num_cap_releases % CEPH_CAPS_PER_RELEASE)) + ceph_flush_cap_releases(session->s_mdsc, session); +} + +static void ceph_cap_reclaim_work(struct work_struct *work) +{ + struct ceph_mds_client *mdsc = + container_of(work, struct ceph_mds_client, cap_reclaim_work); + int ret = ceph_trim_dentries(mdsc); + if (ret == -EAGAIN) + ceph_queue_cap_reclaim_work(mdsc); +} + +void ceph_queue_cap_reclaim_work(struct ceph_mds_client *mdsc) +{ + if (mdsc->stopping) + return; + + if (queue_work(mdsc->fsc->cap_wq, &mdsc->cap_reclaim_work)) { + dout("caps reclaim work queued\n"); + } else { + dout("failed to queue caps release work\n"); + } +} + +void ceph_reclaim_caps_nr(struct ceph_mds_client *mdsc, int nr) +{ + int val; + if (!nr) + return; + val = atomic_add_return(nr, &mdsc->cap_reclaim_pending); + if ((val % CEPH_CAPS_PER_RELEASE) < nr) { + atomic_set(&mdsc->cap_reclaim_pending, 0); + ceph_queue_cap_reclaim_work(mdsc); + } +} + +/* + * requests + */ + +int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req, + struct inode *dir) +{ + struct ceph_inode_info *ci = ceph_inode(dir); + struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info; + struct ceph_mount_options *opt = req->r_mdsc->fsc->mount_options; + size_t size = sizeof(struct ceph_mds_reply_dir_entry); + unsigned int num_entries; + int order; + + 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, 1U); + num_entries = min(num_entries, opt->max_readdir); + + order = get_order(size * num_entries); + while (order >= 0) { + rinfo->dir_entries = (void*)__get_free_pages(GFP_KERNEL | + __GFP_NOWARN, + order); + if (rinfo->dir_entries) + break; + order--; + } + if (!rinfo->dir_entries) + return -ENOMEM; + + num_entries = (PAGE_SIZE << order) / size; + num_entries = min(num_entries, opt->max_readdir); + + rinfo->dir_buf_size = PAGE_SIZE << order; + req->r_num_caps = num_entries + 1; + req->r_args.readdir.max_entries = cpu_to_le32(num_entries); + req->r_args.readdir.max_bytes = cpu_to_le32(opt->max_readdir_bytes); + return 0; +} + +/* + * Create an mds request. + */ +struct ceph_mds_request * +ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode) +{ + struct ceph_mds_request *req; + + req = kmem_cache_zalloc(ceph_mds_request_cachep, GFP_NOFS); + if (!req) + return ERR_PTR(-ENOMEM); + + mutex_init(&req->r_fill_mutex); + req->r_mdsc = mdsc; + req->r_started = jiffies; + req->r_start_latency = ktime_get(); + req->r_resend_mds = -1; + INIT_LIST_HEAD(&req->r_unsafe_dir_item); + INIT_LIST_HEAD(&req->r_unsafe_target_item); + req->r_fmode = -1; + kref_init(&req->r_kref); + RB_CLEAR_NODE(&req->r_node); + INIT_LIST_HEAD(&req->r_wait); + init_completion(&req->r_completion); + init_completion(&req->r_safe_completion); + INIT_LIST_HEAD(&req->r_unsafe_item); + + ktime_get_coarse_real_ts64(&req->r_stamp); + + req->r_op = op; + req->r_direct_mode = mode; + return req; +} + +/* + * return oldest (lowest) request, tid in request tree, 0 if none. + * + * called under mdsc->mutex. + */ +static struct ceph_mds_request *__get_oldest_req(struct ceph_mds_client *mdsc) +{ + if (RB_EMPTY_ROOT(&mdsc->request_tree)) + return NULL; + return rb_entry(rb_first(&mdsc->request_tree), + struct ceph_mds_request, r_node); +} + +static inline u64 __get_oldest_tid(struct ceph_mds_client *mdsc) +{ + return mdsc->oldest_tid; +} + +/* + * Build a dentry's path. Allocate on heap; caller must kfree. Based + * on build_path_from_dentry in fs/cifs/dir.c. + * + * If @stop_on_nosnap, generate path relative to the first non-snapped + * inode. + * + * Encode hidden .snap dirs as a double /, i.e. + * foo/.snap/bar -> foo//bar + */ +char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *pbase, + int stop_on_nosnap) +{ + struct dentry *temp; + char *path; + int pos; + unsigned seq; + u64 base; + + if (!dentry) + return ERR_PTR(-EINVAL); + + path = __getname(); + if (!path) + return ERR_PTR(-ENOMEM); +retry: + pos = PATH_MAX - 1; + path[pos] = '\0'; + + seq = read_seqbegin(&rename_lock); + rcu_read_lock(); + temp = dentry; + for (;;) { + 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 && dentry != temp && + ceph_snap(inode) == CEPH_NOSNAP) { + spin_unlock(&temp->d_lock); + pos++; /* get rid of any prepended '/' */ + break; + } else { + pos -= temp->d_name.len; + if (pos < 0) { + spin_unlock(&temp->d_lock); + break; + } + memcpy(path + pos, temp->d_name.name, temp->d_name.len); + } + spin_unlock(&temp->d_lock); + temp = READ_ONCE(temp->d_parent); + + /* Are we at the root? */ + if (IS_ROOT(temp)) + break; + + /* Are we out of buffer? */ + if (--pos < 0) + break; + + path[pos] = '/'; + } + base = ceph_ino(d_inode(temp)); + rcu_read_unlock(); + + if (read_seqretry(&rename_lock, seq)) + goto retry; + + if (pos < 0) { + /* + * A rename didn't occur, but somehow we didn't end up where + * we thought we would. Throw a warning and try again. + */ + pr_warn("build_path did not end path lookup where " + "expected, pos is %d\n", pos); + goto retry; + } + + *pbase = base; + *plen = PATH_MAX - 1 - pos; + dout("build_path on %p %d built %llx '%.*s'\n", + dentry, d_count(dentry), base, *plen, path + pos); + return path + pos; +} + +static int build_dentry_path(struct dentry *dentry, struct inode *dir, + const char **ppath, int *ppathlen, u64 *pino, + bool *pfreepath, bool parent_locked) +{ + char *path; + + rcu_read_lock(); + if (!dir) + dir = d_inode_rcu(dentry->d_parent); + if (dir && parent_locked && ceph_snap(dir) == CEPH_NOSNAP) { + *pino = ceph_ino(dir); + rcu_read_unlock(); + *ppath = dentry->d_name.name; + *ppathlen = dentry->d_name.len; + return 0; + } + rcu_read_unlock(); + path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1); + if (IS_ERR(path)) + return PTR_ERR(path); + *ppath = path; + *pfreepath = true; + return 0; +} + +static int build_inode_path(struct inode *inode, + const char **ppath, int *ppathlen, u64 *pino, + bool *pfreepath) +{ + struct dentry *dentry; + char *path; + + if (ceph_snap(inode) == CEPH_NOSNAP) { + *pino = ceph_ino(inode); + *ppathlen = 0; + return 0; + } + dentry = d_find_alias(inode); + path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1); + dput(dentry); + if (IS_ERR(path)) + return PTR_ERR(path); + *ppath = path; + *pfreepath = true; + return 0; +} + +/* + * request arguments may be specified via an inode *, a dentry *, or + * an explicit ino+path. + */ +static int set_request_path_attr(struct inode *rinode, struct dentry *rdentry, + struct inode *rdiri, const char *rpath, + u64 rino, const char **ppath, int *pathlen, + u64 *ino, bool *freepath, bool parent_locked) +{ + int r = 0; + + if (rinode) { + r = build_inode_path(rinode, ppath, pathlen, ino, freepath); + dout(" inode %p %llx.%llx\n", rinode, ceph_ino(rinode), + ceph_snap(rinode)); + } else if (rdentry) { + r = build_dentry_path(rdentry, rdiri, ppath, pathlen, ino, + freepath, parent_locked); + dout(" dentry %p %llx/%.*s\n", rdentry, *ino, *pathlen, + *ppath); + } else if (rpath || rino) { + *ino = rino; + *ppath = rpath; + *pathlen = rpath ? strlen(rpath) : 0; + dout(" path %.*s\n", *pathlen, rpath); + } + + return r; +} + +/* + * called under mdsc->mutex + */ +static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc, + struct ceph_mds_request *req, + int mds, bool drop_cap_releases) +{ + struct ceph_msg *msg; + struct ceph_mds_request_head *head; + const char *path1 = NULL; + const char *path2 = NULL; + u64 ino1 = 0, ino2 = 0; + int pathlen1 = 0, pathlen2 = 0; + bool freepath1 = false, freepath2 = false; + int len; + u16 releases; + void *p, *end; + int ret; + + ret = set_request_path_attr(req->r_inode, req->r_dentry, + req->r_parent, req->r_path1, req->r_ino1.ino, + &path1, &pathlen1, &ino1, &freepath1, + test_bit(CEPH_MDS_R_PARENT_LOCKED, + &req->r_req_flags)); + if (ret < 0) { + msg = ERR_PTR(ret); + goto out; + } + + /* If r_old_dentry is set, then assume that its parent is locked */ + ret = set_request_path_attr(NULL, req->r_old_dentry, + req->r_old_dentry_dir, + req->r_path2, req->r_ino2.ino, + &path2, &pathlen2, &ino2, &freepath2, true); + if (ret < 0) { + msg = ERR_PTR(ret); + goto out_free1; + } + + len = sizeof(*head) + + pathlen1 + pathlen2 + 2*(1 + sizeof(u32) + sizeof(u64)) + + sizeof(struct ceph_timespec); + + /* calculate (max) length for cap releases */ + len += sizeof(struct ceph_mds_request_release) * + (!!req->r_inode_drop + !!req->r_dentry_drop + + !!req->r_old_inode_drop + !!req->r_old_dentry_drop); + if (req->r_dentry_drop) + len += pathlen1; + if (req->r_old_dentry_drop) + len += pathlen2; + + msg = ceph_msg_new2(CEPH_MSG_CLIENT_REQUEST, len, 1, GFP_NOFS, false); + if (!msg) { + msg = ERR_PTR(-ENOMEM); + goto out_free2; + } + + msg->hdr.version = cpu_to_le16(2); + msg->hdr.tid = cpu_to_le64(req->r_tid); + + head = msg->front.iov_base; + p = msg->front.iov_base + sizeof(*head); + end = msg->front.iov_base + msg->front.iov_len; + + head->mdsmap_epoch = cpu_to_le32(mdsc->mdsmap->m_epoch); + head->op = cpu_to_le32(req->r_op); + head->caller_uid = cpu_to_le32(from_kuid(&init_user_ns, req->r_uid)); + head->caller_gid = cpu_to_le32(from_kgid(&init_user_ns, req->r_gid)); + head->ino = cpu_to_le64(req->r_deleg_ino); + 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, + req->r_op == CEPH_MDS_OP_READDIR); + if (req->r_dentry_drop) + releases += ceph_encode_dentry_release(&p, req->r_dentry, + req->r_parent, mds, req->r_dentry_drop, + req->r_dentry_unless); + if (req->r_old_dentry_drop) + releases += ceph_encode_dentry_release(&p, req->r_old_dentry, + req->r_old_dentry_dir, mds, + req->r_old_dentry_drop, + req->r_old_dentry_unless); + if (req->r_old_inode_drop) + releases += ceph_encode_inode_release(&p, + d_inode(req->r_old_dentry), + mds, req->r_old_inode_drop, req->r_old_inode_unless, 0); + + if (drop_cap_releases) { + releases = 0; + p = msg->front.iov_base + req->r_request_release_offset; + } + + head->num_releases = cpu_to_le16(releases); + + /* time stamp */ + { + struct ceph_timespec ts; + ceph_encode_timespec64(&ts, &req->r_stamp); + ceph_encode_copy(&p, &ts, sizeof(ts)); + } + + if (WARN_ON_ONCE(p > end)) { + ceph_msg_put(msg); + msg = ERR_PTR(-ERANGE); + goto out_free2; + } + + msg->front.iov_len = p - msg->front.iov_base; + msg->hdr.front_len = cpu_to_le32(msg->front.iov_len); + + if (req->r_pagelist) { + struct ceph_pagelist *pagelist = req->r_pagelist; + ceph_msg_data_add_pagelist(msg, pagelist); + msg->hdr.data_len = cpu_to_le32(pagelist->length); + } else { + msg->hdr.data_len = 0; + } + + msg->hdr.data_off = cpu_to_le16(0); + +out_free2: + if (freepath2) + ceph_mdsc_free_path((char *)path2, pathlen2); +out_free1: + if (freepath1) + ceph_mdsc_free_path((char *)path1, pathlen1); +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) +{ + req->r_end_latency = ktime_get(); + + if (req->r_callback) + req->r_callback(mdsc, req); + complete_all(&req->r_completion); +} + +/* + * called under mdsc->mutex + */ +static int __prepare_send_request(struct ceph_mds_client *mdsc, + struct ceph_mds_request *req, + int mds, bool drop_cap_releases) +{ + struct ceph_mds_request_head *rhead; + struct ceph_msg *msg; + int flags = 0; + + req->r_attempts++; + if (req->r_inode) { + struct ceph_cap *cap = + ceph_get_cap_for_mds(ceph_inode(req->r_inode), mds); + + if (cap) + req->r_sent_on_mseq = cap->mseq; + else + req->r_sent_on_mseq = -1; + } + dout("prepare_send_request %p tid %lld %s (attempt %d)\n", req, + req->r_tid, ceph_mds_op_name(req->r_op), req->r_attempts); + + if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) { + void *p; + /* + * Replay. Do not regenerate message (and rebuild + * paths, etc.); just use the original message. + * Rebuilding paths will break for renames because + * d_move mangles the src name. + */ + msg = req->r_request; + rhead = msg->front.iov_base; + + flags = le32_to_cpu(rhead->flags); + flags |= CEPH_MDS_FLAG_REPLAY; + rhead->flags = cpu_to_le32(flags); + + if (req->r_target_inode) + rhead->ino = cpu_to_le64(ceph_ino(req->r_target_inode)); + + rhead->num_retry = req->r_attempts - 1; + + /* remove cap/dentry releases from message */ + rhead->num_releases = 0; + + /* time stamp */ + p = msg->front.iov_base + req->r_request_release_offset; + { + struct ceph_timespec ts; + ceph_encode_timespec64(&ts, &req->r_stamp); + ceph_encode_copy(&p, &ts, sizeof(ts)); + } + + msg->front.iov_len = p - msg->front.iov_base; + msg->hdr.front_len = cpu_to_le32(msg->front.iov_len); + return 0; + } + + if (req->r_request) { + ceph_msg_put(req->r_request); + req->r_request = NULL; + } + msg = create_request_message(mdsc, req, mds, drop_cap_releases); + if (IS_ERR(msg)) { + req->r_err = PTR_ERR(msg); + return PTR_ERR(msg); + } + req->r_request = msg; + + rhead = msg->front.iov_base; + rhead->oldest_client_tid = cpu_to_le64(__get_oldest_tid(mdsc)); + if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) + flags |= CEPH_MDS_FLAG_REPLAY; + if (test_bit(CEPH_MDS_R_ASYNC, &req->r_req_flags)) + flags |= CEPH_MDS_FLAG_ASYNC; + if (req->r_parent) + flags |= CEPH_MDS_FLAG_WANT_DENTRY; + rhead->flags = cpu_to_le32(flags); + rhead->num_fwd = req->r_num_fwd; + rhead->num_retry = req->r_attempts - 1; + + dout(" r_parent = %p\n", req->r_parent); + return 0; +} + +/* + * called under mdsc->mutex + */ +static int __send_request(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session, + struct ceph_mds_request *req, + bool drop_cap_releases) +{ + int err; + + err = __prepare_send_request(mdsc, req, session->s_mds, + drop_cap_releases); + if (!err) { + ceph_msg_get(req->r_request); + ceph_con_send(&session->s_con, req->r_request); + } + + return err; +} + +/* + * send request, or put it on the appropriate wait list. + */ +static void __do_request(struct ceph_mds_client *mdsc, + struct ceph_mds_request *req) +{ + struct ceph_mds_session *session = NULL; + int mds = -1; + int err = 0; + bool random; + + if (req->r_err || test_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags)) { + if (test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags)) + __unregister_request(mdsc, req); + return; + } + + if (req->r_timeout && + time_after_eq(jiffies, req->r_started + req->r_timeout)) { + dout("do_request timed out\n"); + err = -ETIMEDOUT; + goto finish; + } + if (READ_ONCE(mdsc->fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) { + dout("do_request forced umount\n"); + err = -EIO; + goto finish; + } + if (READ_ONCE(mdsc->fsc->mount_state) == CEPH_MOUNT_MOUNTING) { + if (mdsc->mdsmap_err) { + err = mdsc->mdsmap_err; + dout("do_request mdsmap err %d\n", err); + goto finish; + } + if (mdsc->mdsmap->m_epoch == 0) { + dout("do_request no mdsmap, waiting for map\n"); + list_add(&req->r_wait, &mdsc->waiting_for_map); + return; + } + if (!(mdsc->fsc->mount_options->flags & + CEPH_MOUNT_OPT_MOUNTWAIT) && + !ceph_mdsmap_is_cluster_available(mdsc->mdsmap)) { + err = -EHOSTUNREACH; + goto finish; + } + } + + put_request_session(req); + + mds = __choose_mds(mdsc, req, &random); + if (mds < 0 || + ceph_mdsmap_get_state(mdsc->mdsmap, mds) < CEPH_MDS_STATE_ACTIVE) { + if (test_bit(CEPH_MDS_R_ASYNC, &req->r_req_flags)) { + err = -EJUKEBOX; + goto finish; + } + dout("do_request no mds or not active, waiting for map\n"); + list_add(&req->r_wait, &mdsc->waiting_for_map); + return; + } + + /* get, open session */ + session = __ceph_lookup_mds_session(mdsc, mds); + if (!session) { + session = register_session(mdsc, mds); + if (IS_ERR(session)) { + err = PTR_ERR(session); + goto finish; + } + } + req->r_session = ceph_get_mds_session(session); + + dout("do_request mds%d session %p state %s\n", mds, session, + ceph_session_state_name(session->s_state)); + if (session->s_state != CEPH_MDS_SESSION_OPEN && + session->s_state != CEPH_MDS_SESSION_HUNG) { + if (session->s_state == CEPH_MDS_SESSION_REJECTED) { + err = -EACCES; + goto out_session; + } + /* + * We cannot queue async requests since the caps and delegated + * inodes are bound to the session. Just return -EJUKEBOX and + * let the caller retry a sync request in that case. + */ + if (test_bit(CEPH_MDS_R_ASYNC, &req->r_req_flags)) { + err = -EJUKEBOX; + goto out_session; + } + if (session->s_state == CEPH_MDS_SESSION_NEW || + session->s_state == CEPH_MDS_SESSION_CLOSING) { + err = __open_session(mdsc, session); + if (err) + goto out_session; + /* retry the same mds later */ + if (random) + req->r_resend_mds = mds; + } + 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 = __send_request(mdsc, session, req, false); + +out_session: + ceph_put_mds_session(session); +finish: + if (err) { + dout("__do_request early error %d\n", err); + req->r_err = err; + complete_request(mdsc, req); + __unregister_request(mdsc, req); + } + return; +} + +/* + * called under mdsc->mutex + */ +static void __wake_requests(struct ceph_mds_client *mdsc, + struct list_head *head) +{ + struct ceph_mds_request *req; + LIST_HEAD(tmp_list); + + list_splice_init(head, &tmp_list); + + while (!list_empty(&tmp_list)) { + req = list_entry(tmp_list.next, + struct ceph_mds_request, r_wait); + list_del_init(&req->r_wait); + dout(" wake request %p tid %llu\n", req, req->r_tid); + __do_request(mdsc, req); + } +} + +/* + * Wake up threads with requests pending for @mds, so that they can + * resubmit their requests to a possibly different mds. + */ +static void kick_requests(struct ceph_mds_client *mdsc, int mds) +{ + struct ceph_mds_request *req; + struct rb_node *p = rb_first(&mdsc->request_tree); + + dout("kick_requests mds%d\n", mds); + while (p) { + req = rb_entry(p, struct ceph_mds_request, r_node); + p = rb_next(p); + if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) + continue; + if (req->r_attempts > 0) + continue; /* only new requests */ + if (req->r_session && + req->r_session->s_mds == mds) { + dout(" kicking tid %llu\n", req->r_tid); + list_del_init(&req->r_wait); + __do_request(mdsc, req); + } + } +} + +int ceph_mdsc_submit_request(struct ceph_mds_client *mdsc, struct inode *dir, + struct ceph_mds_request *req) +{ + int err = 0; + + /* take CAP_PIN refs for r_inode, r_parent, r_old_dentry */ + if (req->r_inode) + ceph_get_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN); + if (req->r_parent) { + struct ceph_inode_info *ci = ceph_inode(req->r_parent); + int fmode = (req->r_op & CEPH_MDS_OP_WRITE) ? + CEPH_FILE_MODE_WR : CEPH_FILE_MODE_RD; + spin_lock(&ci->i_ceph_lock); + ceph_take_cap_refs(ci, CEPH_CAP_PIN, false); + __ceph_touch_fmode(ci, mdsc, fmode); + spin_unlock(&ci->i_ceph_lock); + ihold(req->r_parent); + } + if (req->r_old_dentry_dir) + ceph_get_cap_refs(ceph_inode(req->r_old_dentry_dir), + CEPH_CAP_PIN); + + if (req->r_inode) { + err = ceph_wait_on_async_create(req->r_inode); + if (err) { + dout("%s: wait for async create returned: %d\n", + __func__, err); + return err; + } + } + + if (!err && req->r_old_inode) { + err = ceph_wait_on_async_create(req->r_old_inode); + if (err) { + dout("%s: wait for async create returned: %d\n", + __func__, err); + return err; + } + } + + dout("submit_request on %p for inode %p\n", req, dir); + mutex_lock(&mdsc->mutex); + __register_request(mdsc, req, dir); + __do_request(mdsc, req); + err = req->r_err; + mutex_unlock(&mdsc->mutex); + return err; +} + +static int ceph_mdsc_wait_request(struct ceph_mds_client *mdsc, + struct ceph_mds_request *req) +{ + int err; + + /* wait */ + dout("do_request waiting\n"); + if (!req->r_timeout && req->r_wait_for_completion) { + err = req->r_wait_for_completion(mdsc, req); + } else { + long timeleft = wait_for_completion_killable_timeout( + &req->r_completion, + ceph_timeout_jiffies(req->r_timeout)); + if (timeleft > 0) + err = 0; + else if (!timeleft) + err = -ETIMEDOUT; /* timed out */ + else + err = timeleft; /* killed */ + } + dout("do_request waited, got %d\n", err); + mutex_lock(&mdsc->mutex); + + /* only abort if we didn't race with a real reply */ + if (test_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags)) { + err = le32_to_cpu(req->r_reply_info.head->result); + } else if (err < 0) { + dout("aborted request %lld with %d\n", req->r_tid, err); + + /* + * ensure we aren't running concurrently with + * ceph_fill_trace or ceph_readdir_prepopulate, which + * rely on locks (dir mutex) held by our caller. + */ + mutex_lock(&req->r_fill_mutex); + req->r_err = err; + set_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags); + mutex_unlock(&req->r_fill_mutex); + + if (req->r_parent && + (req->r_op & CEPH_MDS_OP_WRITE)) + ceph_invalidate_dir_request(req); + } else { + err = req->r_err; + } + + mutex_unlock(&mdsc->mutex); + return err; +} + +/* + * 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); + + /* issue */ + err = ceph_mdsc_submit_request(mdsc, dir, req); + if (!err) + err = ceph_mdsc_wait_request(mdsc, req); + dout("do_request %p done, result %d\n", req, err); + return err; +} + +/* + * Invalidate dir's completeness, dentry lease state on an aborted MDS + * namespace request. + */ +void ceph_invalidate_dir_request(struct ceph_mds_request *req) +{ + struct inode *dir = req->r_parent; + struct inode *old_dir = req->r_old_dentry_dir; + + dout("invalidate_dir_request %p %p (complete, lease(s))\n", dir, old_dir); + + ceph_dir_clear_complete(dir); + if (old_dir) + ceph_dir_clear_complete(old_dir); + if (req->r_dentry) + ceph_invalidate_dentry_lease(req->r_dentry); + if (req->r_old_dentry) + ceph_invalidate_dentry_lease(req->r_old_dentry); +} + +/* + * Handle mds reply. + * + * We take the session mutex and parse and process the reply immediately. + * This preserves the logical ordering of replies, capabilities, etc., sent + * by the MDS as they are applied to our local cache. + */ +static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg) +{ + struct ceph_mds_client *mdsc = session->s_mdsc; + struct ceph_mds_request *req; + struct ceph_mds_reply_head *head = msg->front.iov_base; + struct ceph_mds_reply_info_parsed *rinfo; /* parsed reply info */ + struct ceph_snap_realm *realm; + u64 tid; + int err, result; + int mds = session->s_mds; + + if (msg->front.iov_len < sizeof(*head)) { + pr_err("mdsc_handle_reply got corrupt (short) reply\n"); + ceph_msg_dump(msg); + return; + } + + /* get request, session */ + tid = le64_to_cpu(msg->hdr.tid); + mutex_lock(&mdsc->mutex); + req = lookup_get_request(mdsc, tid); + if (!req) { + dout("handle_reply on unknown tid %llu\n", tid); + mutex_unlock(&mdsc->mutex); + return; + } + dout("handle_reply %p\n", req); + + /* correct session? */ + if (req->r_session != session) { + pr_err("mdsc_handle_reply got %llu on session mds%d" + " not mds%d\n", tid, session->s_mds, + req->r_session ? req->r_session->s_mds : -1); + mutex_unlock(&mdsc->mutex); + goto out; + } + + /* dup? */ + if ((test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags) && !head->safe) || + (test_bit(CEPH_MDS_R_GOT_SAFE, &req->r_req_flags) && head->safe)) { + pr_warn("got a dup %s reply on %llu from mds%d\n", + head->safe ? "safe" : "unsafe", tid, mds); + mutex_unlock(&mdsc->mutex); + goto out; + } + if (test_bit(CEPH_MDS_R_GOT_SAFE, &req->r_req_flags)) { + pr_warn("got unsafe after safe on %llu from mds%d\n", + tid, mds); + mutex_unlock(&mdsc->mutex); + goto out; + } + + result = le32_to_cpu(head->result); + + /* + * Handle an ESTALE + * if we're not talking to the authority, send to them + * if the authority has changed while we weren't looking, + * send to new authority + * Otherwise we just have to return an ESTALE + */ + if (result == -ESTALE) { + dout("got ESTALE on request %llu\n", req->r_tid); + req->r_resend_mds = -1; + if (req->r_direct_mode != USE_AUTH_MDS) { + dout("not using auth, setting for that now\n"); + req->r_direct_mode = USE_AUTH_MDS; + __do_request(mdsc, req); + mutex_unlock(&mdsc->mutex); + goto out; + } else { + int mds = __choose_mds(mdsc, req, NULL); + if (mds >= 0 && mds != req->r_session->s_mds) { + dout("but auth changed, so resending\n"); + __do_request(mdsc, req); + mutex_unlock(&mdsc->mutex); + goto out; + } + } + dout("have to return ESTALE on request %llu\n", req->r_tid); + } + + + if (head->safe) { + set_bit(CEPH_MDS_R_GOT_SAFE, &req->r_req_flags); + __unregister_request(mdsc, req); + + /* last request during umount? */ + if (mdsc->stopping && !__get_oldest_req(mdsc)) + complete_all(&mdsc->safe_umount_waiters); + + if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) { + /* + * We already handled the unsafe response, now do the + * cleanup. No need to examine the response; the MDS + * doesn't include any result info in the safe + * response. And even if it did, there is nothing + * useful we could do with a revised return value. + */ + dout("got safe reply %llu, mds%d\n", tid, mds); + + mutex_unlock(&mdsc->mutex); + goto out; + } + } else { + set_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags); + list_add_tail(&req->r_unsafe_item, &req->r_session->s_unsafe); + } + + dout("handle_reply tid %lld result %d\n", tid, result); + rinfo = &req->r_reply_info; + if (test_bit(CEPHFS_FEATURE_REPLY_ENCODING, &session->s_features)) + err = parse_reply_info(session, msg, rinfo, (u64)-1); + else + err = parse_reply_info(session, msg, rinfo, session->s_con.peer_features); + mutex_unlock(&mdsc->mutex); + + mutex_lock(&session->s_mutex); + if (err < 0) { + pr_err("mdsc_handle_reply got corrupt reply mds%d(tid:%lld)\n", mds, tid); + ceph_msg_dump(msg); + goto out_err; + } + + /* snap trace */ + realm = NULL; + if (rinfo->snapblob_len) { + down_write(&mdsc->snap_rwsem); + ceph_update_snap_trace(mdsc, rinfo->snapblob, + rinfo->snapblob + rinfo->snapblob_len, + le32_to_cpu(head->op) == CEPH_MDS_OP_RMSNAP, + &realm); + downgrade_write(&mdsc->snap_rwsem); + } else { + down_read(&mdsc->snap_rwsem); + } + + /* insert trace into our cache */ + mutex_lock(&req->r_fill_mutex); + current->journal_info = req; + err = ceph_fill_trace(mdsc->fsc->sb, req); + if (err == 0) { + if (result == 0 && (req->r_op == CEPH_MDS_OP_READDIR || + req->r_op == CEPH_MDS_OP_LSSNAP)) + ceph_readdir_prepopulate(req, req->r_session); + } + current->journal_info = NULL; + mutex_unlock(&req->r_fill_mutex); + + up_read(&mdsc->snap_rwsem); + if (realm) + ceph_put_snap_realm(mdsc, realm); + + if (err == 0) { + if (req->r_target_inode && + test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) { + struct ceph_inode_info *ci = + ceph_inode(req->r_target_inode); + spin_lock(&ci->i_unsafe_lock); + list_add_tail(&req->r_unsafe_target_item, + &ci->i_unsafe_iops); + spin_unlock(&ci->i_unsafe_lock); + } + + ceph_unreserve_caps(mdsc, &req->r_caps_reservation); + } +out_err: + mutex_lock(&mdsc->mutex); + if (!test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags)) { + if (err) { + req->r_err = err; + } else { + req->r_reply = ceph_msg_get(msg); + set_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags); + } + } else { + dout("reply arrived after request %lld was aborted\n", tid); + } + mutex_unlock(&mdsc->mutex); + + mutex_unlock(&session->s_mutex); + + /* kick calling process */ + complete_request(mdsc, req); + + ceph_update_metadata_latency(&mdsc->metric, req->r_start_latency, + req->r_end_latency, err); +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_get_request(mdsc, tid); + if (!req) { + dout("forward tid %llu to mds%d - req dne\n", tid, next_mds); + goto out; /* dup reply? */ + } + + if (test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags)) { + 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(test_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags)); + 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); +} + +static int __decode_session_metadata(void **p, void *end, + bool *blocklisted) +{ + /* map<string,string> */ + u32 n; + bool err_str; + ceph_decode_32_safe(p, end, n, bad); + while (n-- > 0) { + u32 len; + ceph_decode_32_safe(p, end, len, bad); + ceph_decode_need(p, end, len, bad); + err_str = !strncmp(*p, "error_string", len); + *p += len; + ceph_decode_32_safe(p, end, len, bad); + ceph_decode_need(p, end, len, bad); + /* + * Match "blocklisted (blacklisted)" from newer MDSes, + * or "blacklisted" from older MDSes. + */ + if (err_str && strnstr(*p, "blacklisted", len)) + *blocklisted = true; + *p += len; + } + return 0; +bad: + return -1; +} + +/* + * 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; + int mds = session->s_mds; + int msg_version = le16_to_cpu(msg->hdr.version); + void *p = msg->front.iov_base; + void *end = p + msg->front.iov_len; + struct ceph_mds_session_head *h; + u32 op; + u64 seq, features = 0; + int wake = 0; + bool blocklisted = false; + + /* decode */ + ceph_decode_need(&p, end, sizeof(*h), bad); + h = p; + p += sizeof(*h); + + op = le32_to_cpu(h->op); + seq = le64_to_cpu(h->seq); + + if (msg_version >= 3) { + u32 len; + /* version >= 2, metadata */ + if (__decode_session_metadata(&p, end, &blocklisted) < 0) + goto bad; + /* version >= 3, feature bits */ + ceph_decode_32_safe(&p, end, len, bad); + if (len) { + ceph_decode_64_safe(&p, end, features, bad); + p += len - sizeof(features); + } + } + + mutex_lock(&mdsc->mutex); + if (op == CEPH_SESSION_CLOSE) { + ceph_get_mds_session(session); + __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; + session->s_features = features; + renewed_caps(mdsc, session, 0); + if (test_bit(CEPHFS_FEATURE_METRIC_COLLECT, &session->s_features)) + metric_schedule_delayed(&mdsc->metric); + 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); + session->s_state = CEPH_MDS_SESSION_CLOSED; + 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: + ceph_trim_caps(mdsc, session, le32_to_cpu(h->max_caps)); + break; + + case CEPH_SESSION_FLUSHMSG: + /* flush cap releases */ + spin_lock(&session->s_cap_lock); + if (session->s_num_cap_releases) + ceph_flush_cap_releases(mdsc, session); + spin_unlock(&session->s_cap_lock); + + 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, FORCE_RO); + break; + + case CEPH_SESSION_REJECT: + WARN_ON(session->s_state != CEPH_MDS_SESSION_OPENING); + pr_info("mds%d rejected session\n", session->s_mds); + session->s_state = CEPH_MDS_SESSION_REJECTED; + cleanup_session_requests(mdsc, session); + remove_session_caps(session); + if (blocklisted) + mdsc->fsc->blocklisted = true; + wake = 2; /* for good measure */ + 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); + } + if (op == CEPH_SESSION_CLOSE) + ceph_put_mds_session(session); + 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; +} + +void ceph_mdsc_release_dir_caps(struct ceph_mds_request *req) +{ + int dcaps; + + dcaps = xchg(&req->r_dir_caps, 0); + if (dcaps) { + dout("releasing r_dir_caps=%s\n", ceph_cap_string(dcaps)); + ceph_put_cap_refs(ceph_inode(req->r_parent), dcaps); + } +} + +void ceph_mdsc_release_dir_caps_no_check(struct ceph_mds_request *req) +{ + int dcaps; + + dcaps = xchg(&req->r_dir_caps, 0); + if (dcaps) { + dout("releasing r_dir_caps=%s\n", ceph_cap_string(dcaps)); + ceph_put_cap_refs_no_check_caps(ceph_inode(req->r_parent), + dcaps); + } +} + +/* + * 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; + + 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) + __send_request(mdsc, session, req, true); + + /* + * 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 (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) + continue; + if (req->r_attempts == 0) + continue; /* only old requests */ + if (!req->r_session) + continue; + if (req->r_session->s_mds != session->s_mds) + continue; + + ceph_mdsc_release_dir_caps_no_check(req); + + __send_request(mdsc, session, req, true); + } + mutex_unlock(&mdsc->mutex); +} + +static int send_reconnect_partial(struct ceph_reconnect_state *recon_state) +{ + struct ceph_msg *reply; + struct ceph_pagelist *_pagelist; + struct page *page; + __le32 *addr; + int err = -ENOMEM; + + if (!recon_state->allow_multi) + return -ENOSPC; + + /* can't handle message that contains both caps and realm */ + BUG_ON(!recon_state->nr_caps == !recon_state->nr_realms); + + /* pre-allocate new pagelist */ + _pagelist = ceph_pagelist_alloc(GFP_NOFS); + if (!_pagelist) + return -ENOMEM; + + reply = ceph_msg_new2(CEPH_MSG_CLIENT_RECONNECT, 0, 1, GFP_NOFS, false); + if (!reply) + goto fail_msg; + + /* placeholder for nr_caps */ + err = ceph_pagelist_encode_32(_pagelist, 0); + if (err < 0) + goto fail; + + if (recon_state->nr_caps) { + /* currently encoding caps */ + err = ceph_pagelist_encode_32(recon_state->pagelist, 0); + if (err) + goto fail; + } else { + /* placeholder for nr_realms (currently encoding relams) */ + err = ceph_pagelist_encode_32(_pagelist, 0); + if (err < 0) + goto fail; + } + + err = ceph_pagelist_encode_8(recon_state->pagelist, 1); + if (err) + goto fail; + + page = list_first_entry(&recon_state->pagelist->head, struct page, lru); + addr = kmap_atomic(page); + if (recon_state->nr_caps) { + /* currently encoding caps */ + *addr = cpu_to_le32(recon_state->nr_caps); + } else { + /* currently encoding relams */ + *(addr + 1) = cpu_to_le32(recon_state->nr_realms); + } + kunmap_atomic(addr); + + reply->hdr.version = cpu_to_le16(5); + reply->hdr.compat_version = cpu_to_le16(4); + + reply->hdr.data_len = cpu_to_le32(recon_state->pagelist->length); + ceph_msg_data_add_pagelist(reply, recon_state->pagelist); + + ceph_con_send(&recon_state->session->s_con, reply); + ceph_pagelist_release(recon_state->pagelist); + + recon_state->pagelist = _pagelist; + recon_state->nr_caps = 0; + recon_state->nr_realms = 0; + recon_state->msg_version = 5; + return 0; +fail: + ceph_msg_put(reply); +fail_msg: + ceph_pagelist_release(_pagelist); + return err; +} + +static struct dentry* d_find_primary(struct inode *inode) +{ + struct dentry *alias, *dn = NULL; + + if (hlist_empty(&inode->i_dentry)) + return NULL; + + spin_lock(&inode->i_lock); + if (hlist_empty(&inode->i_dentry)) + goto out_unlock; + + if (S_ISDIR(inode->i_mode)) { + alias = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias); + if (!IS_ROOT(alias)) + dn = dget(alias); + goto out_unlock; + } + + hlist_for_each_entry(alias, &inode->i_dentry, d_u.d_alias) { + spin_lock(&alias->d_lock); + if (!d_unhashed(alias) && + (ceph_dentry(alias)->flags & CEPH_DENTRY_PRIMARY_LINK)) { + dn = dget_dlock(alias); + } + spin_unlock(&alias->d_lock); + if (dn) + break; + } +out_unlock: + spin_unlock(&inode->i_lock); + return dn; +} + +/* + * Encode information about a cap for a reconnect with the MDS. + */ +static int reconnect_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; + struct ceph_inode_info *ci = cap->ci; + struct ceph_reconnect_state *recon_state = arg; + struct ceph_pagelist *pagelist = recon_state->pagelist; + struct dentry *dentry; + char *path; + int pathlen = 0, err; + u64 pathbase; + u64 snap_follows; + + dout(" adding %p ino %llx.%llx cap %p %lld %s\n", + inode, ceph_vinop(inode), cap, cap->cap_id, + ceph_cap_string(cap->issued)); + + dentry = d_find_primary(inode); + if (dentry) { + /* set pathbase to parent dir when msg_version >= 2 */ + path = ceph_mdsc_build_path(dentry, &pathlen, &pathbase, + recon_state->msg_version >= 2); + dput(dentry); + if (IS_ERR(path)) { + err = PTR_ERR(path); + goto out_err; + } + } else { + path = NULL; + pathbase = 0; + } + + 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; + + /* These are lost when the session goes away */ + if (S_ISDIR(inode->i_mode)) { + if (cap->issued & CEPH_CAP_DIR_CREATE) { + ceph_put_string(rcu_dereference_raw(ci->i_cached_layout.pool_ns)); + memset(&ci->i_cached_layout, 0, sizeof(ci->i_cached_layout)); + } + cap->issued &= ~CEPH_CAP_ANY_DIR_OPS; + } + + if (recon_state->msg_version >= 2) { + 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 = (__force __le32) + ((ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK) ? 0 : 1); + } 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_timespec64(&rec.v1.mtime, &inode->i_mtime); + ceph_encode_timespec64(&rec.v1.atime, &inode->i_atime); + rec.v1.snaprealm = cpu_to_le64(ci->i_snap_realm->ino); + rec.v1.pathbase = cpu_to_le64(pathbase); + } + + if (list_empty(&ci->i_cap_snaps)) { + snap_follows = ci->i_head_snapc ? ci->i_head_snapc->seq : 0; + } else { + struct ceph_cap_snap *capsnap = + list_first_entry(&ci->i_cap_snaps, + struct ceph_cap_snap, ci_item); + snap_follows = capsnap->follows; + } + spin_unlock(&ci->i_ceph_lock); + + if (recon_state->msg_version >= 2) { + int num_fcntl_locks, num_flock_locks; + struct ceph_filelock *flocks = NULL; + size_t struct_len, total_len = sizeof(u64); + u8 struct_v = 0; + +encode_again: + if (rec.v2.flock_len) { + ceph_count_locks(inode, &num_fcntl_locks, &num_flock_locks); + } else { + num_fcntl_locks = 0; + num_flock_locks = 0; + } + if (num_fcntl_locks + num_flock_locks > 0) { + flocks = kmalloc_array(num_fcntl_locks + num_flock_locks, + sizeof(struct ceph_filelock), + GFP_NOFS); + if (!flocks) { + err = -ENOMEM; + goto out_err; + } + err = ceph_encode_locks_to_buffer(inode, flocks, + num_fcntl_locks, + num_flock_locks); + if (err) { + kfree(flocks); + flocks = NULL; + if (err == -ENOSPC) + goto encode_again; + goto out_err; + } + } else { + kfree(flocks); + flocks = NULL; + } + + if (recon_state->msg_version >= 3) { + /* version, compat_version and struct_len */ + total_len += 2 * sizeof(u8) + sizeof(u32); + struct_v = 2; + } + /* + * number of encoded locks is stable, so copy to pagelist + */ + struct_len = 2 * sizeof(u32) + + (num_fcntl_locks + num_flock_locks) * + sizeof(struct ceph_filelock); + rec.v2.flock_len = cpu_to_le32(struct_len); + + struct_len += sizeof(u32) + pathlen + sizeof(rec.v2); + + if (struct_v >= 2) + struct_len += sizeof(u64); /* snap_follows */ + + total_len += struct_len; + + if (pagelist->length + total_len > RECONNECT_MAX_SIZE) { + err = send_reconnect_partial(recon_state); + if (err) + goto out_freeflocks; + pagelist = recon_state->pagelist; + } + + err = ceph_pagelist_reserve(pagelist, total_len); + if (err) + goto out_freeflocks; + + ceph_pagelist_encode_64(pagelist, ceph_ino(inode)); + if (recon_state->msg_version >= 3) { + ceph_pagelist_encode_8(pagelist, struct_v); + ceph_pagelist_encode_8(pagelist, 1); + ceph_pagelist_encode_32(pagelist, struct_len); + } + ceph_pagelist_encode_string(pagelist, path, pathlen); + ceph_pagelist_append(pagelist, &rec, sizeof(rec.v2)); + ceph_locks_to_pagelist(flocks, pagelist, + num_fcntl_locks, num_flock_locks); + if (struct_v >= 2) + ceph_pagelist_encode_64(pagelist, snap_follows); +out_freeflocks: + kfree(flocks); + } else { + err = ceph_pagelist_reserve(pagelist, + sizeof(u64) + sizeof(u32) + + pathlen + sizeof(rec.v1)); + if (err) + goto out_err; + + ceph_pagelist_encode_64(pagelist, ceph_ino(inode)); + ceph_pagelist_encode_string(pagelist, path, pathlen); + ceph_pagelist_append(pagelist, &rec, sizeof(rec.v1)); + } + +out_err: + ceph_mdsc_free_path(path, pathlen); + if (!err) + recon_state->nr_caps++; + return err; +} + +static int encode_snap_realms(struct ceph_mds_client *mdsc, + struct ceph_reconnect_state *recon_state) +{ + struct rb_node *p; + struct ceph_pagelist *pagelist = recon_state->pagelist; + int err = 0; + + if (recon_state->msg_version >= 4) { + err = ceph_pagelist_encode_32(pagelist, mdsc->num_snap_realms); + if (err < 0) + goto fail; + } + + /* + * snaprealms. we provide mds with the ino, seq (version), and + * parent for all of our realms. If the mds has any newer info, + * it will tell us. + */ + for (p = rb_first(&mdsc->snap_realms); p; p = rb_next(p)) { + struct ceph_snap_realm *realm = + rb_entry(p, struct ceph_snap_realm, node); + struct ceph_mds_snaprealm_reconnect sr_rec; + + if (recon_state->msg_version >= 4) { + size_t need = sizeof(u8) * 2 + sizeof(u32) + + sizeof(sr_rec); + + if (pagelist->length + need > RECONNECT_MAX_SIZE) { + err = send_reconnect_partial(recon_state); + if (err) + goto fail; + pagelist = recon_state->pagelist; + } + + err = ceph_pagelist_reserve(pagelist, need); + if (err) + goto fail; + + ceph_pagelist_encode_8(pagelist, 1); + ceph_pagelist_encode_8(pagelist, 1); + ceph_pagelist_encode_32(pagelist, sizeof(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; + + recon_state->nr_realms++; + } +fail: + 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. + */ +static void send_mds_reconnect(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session) +{ + struct ceph_msg *reply; + int mds = session->s_mds; + int err = -ENOMEM; + struct ceph_reconnect_state recon_state = { + .session = session, + }; + LIST_HEAD(dispose); + + pr_info("mds%d reconnect start\n", mds); + + recon_state.pagelist = ceph_pagelist_alloc(GFP_NOFS); + if (!recon_state.pagelist) + goto fail_nopagelist; + + reply = ceph_msg_new2(CEPH_MSG_CLIENT_RECONNECT, 0, 1, GFP_NOFS, false); + if (!reply) + goto fail_nomsg; + + xa_destroy(&session->s_delegated_inos); + + 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 */ + detach_cap_releases(session, &dispose); + spin_unlock(&session->s_cap_lock); + dispose_cap_releases(mdsc, &dispose); + + /* 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); + + ceph_early_kick_flushing_caps(mdsc, session); + + down_read(&mdsc->snap_rwsem); + + /* placeholder for nr_caps */ + err = ceph_pagelist_encode_32(recon_state.pagelist, 0); + if (err) + goto fail; + + if (test_bit(CEPHFS_FEATURE_MULTI_RECONNECT, &session->s_features)) { + recon_state.msg_version = 3; + recon_state.allow_multi = true; + } else if (session->s_con.peer_features & CEPH_FEATURE_MDSENC) { + recon_state.msg_version = 3; + } else { + recon_state.msg_version = 2; + } + /* trsaverse this session's caps */ + err = ceph_iterate_session_caps(session, reconnect_caps_cb, &recon_state); + + spin_lock(&session->s_cap_lock); + session->s_cap_reconnect = 0; + spin_unlock(&session->s_cap_lock); + + if (err < 0) + goto fail; + + /* check if all realms can be encoded into current message */ + if (mdsc->num_snap_realms) { + size_t total_len = + recon_state.pagelist->length + + mdsc->num_snap_realms * + sizeof(struct ceph_mds_snaprealm_reconnect); + if (recon_state.msg_version >= 4) { + /* number of realms */ + total_len += sizeof(u32); + /* version, compat_version and struct_len */ + total_len += mdsc->num_snap_realms * + (2 * sizeof(u8) + sizeof(u32)); + } + if (total_len > RECONNECT_MAX_SIZE) { + if (!recon_state.allow_multi) { + err = -ENOSPC; + goto fail; + } + if (recon_state.nr_caps) { + err = send_reconnect_partial(&recon_state); + if (err) + goto fail; + } + recon_state.msg_version = 5; + } + } + + err = encode_snap_realms(mdsc, &recon_state); + if (err < 0) + goto fail; + + if (recon_state.msg_version >= 5) { + err = ceph_pagelist_encode_8(recon_state.pagelist, 0); + if (err < 0) + goto fail; + } + + if (recon_state.nr_caps || recon_state.nr_realms) { + struct page *page = + list_first_entry(&recon_state.pagelist->head, + struct page, lru); + __le32 *addr = kmap_atomic(page); + if (recon_state.nr_caps) { + WARN_ON(recon_state.nr_realms != mdsc->num_snap_realms); + *addr = cpu_to_le32(recon_state.nr_caps); + } else if (recon_state.msg_version >= 4) { + *(addr + 1) = cpu_to_le32(recon_state.nr_realms); + } + kunmap_atomic(addr); + } + + reply->hdr.version = cpu_to_le16(recon_state.msg_version); + if (recon_state.msg_version >= 4) + reply->hdr.compat_version = cpu_to_le16(4); + + reply->hdr.data_len = cpu_to_le32(recon_state.pagelist->length); + ceph_msg_data_add_pagelist(reply, recon_state.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); + ceph_pagelist_release(recon_state.pagelist); + return; + +fail: + ceph_msg_put(reply); + up_read(&mdsc->snap_rwsem); + mutex_unlock(&session->s_mutex); +fail_nomsg: + ceph_pagelist_release(recon_state.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->possible_max_rank && i < mdsc->max_sessions; i++) { + if (!mdsc->sessions[i]) + 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->possible_max_rank) { + /* force close session for stopped mds */ + ceph_get_mds_session(s); + __unregister_session(mdsc, s); + __wake_requests(mdsc, &s->s_waiting); + mutex_unlock(&mdsc->mutex); + + mutex_lock(&s->s_mutex); + cleanup_session_requests(mdsc, s); + remove_session_caps(s); + mutex_unlock(&s->s_mutex); + + ceph_put_mds_session(s); + + mutex_lock(&mdsc->mutex); + kick_requests(mdsc, i); + continue; + } + + if (memcmp(ceph_mdsmap_get_addr(oldmap, i), + ceph_mdsmap_get_addr(newmap, i), + sizeof(struct ceph_entity_addr))) { + /* 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); + mutex_unlock(&mdsc->mutex); + mutex_lock(&s->s_mutex); + mutex_lock(&mdsc->mutex); + ceph_kick_flushing_caps(mdsc, s); + mutex_unlock(&s->s_mutex); + wake_up_session_caps(s, RECONNECT); + } + } + + for (i = 0; i < newmap->possible_max_rank && 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.len = get_unaligned_le32(h + 1); + if (msg->front.iov_len < sizeof(*h) + sizeof(u32) + dname.len) + goto bad; + dname.name = (void *)(h + 1) + sizeof(u32); + + /* 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); + inc_session_sequence(session); + + if (!inode) { + 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(parent, 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; + di->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: + mutex_unlock(&session->s_mutex); + /* avoid calling iput_final() in mds dispatch threads */ + ceph_async_iput(inode); + return; + +bad: + pr_err("corrupt lease message\n"); + ceph_msg_dump(msg); +} + +void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session, + struct dentry *dentry, char action, + u32 seq) +{ + struct ceph_msg *msg; + struct ceph_mds_lease *lease; + struct inode *dir; + int len = sizeof(*lease) + sizeof(u32) + NAME_MAX; + + dout("lease_send_msg identry %p %s to mds%d\n", + dentry, ceph_lease_op_name(action), session->s_mds); + + msg = ceph_msg_new(CEPH_MSG_CLIENT_LEASE, len, GFP_NOFS, false); + if (!msg) + return; + lease = msg->front.iov_base; + lease->action = action; + lease->seq = cpu_to_le32(seq); + + spin_lock(&dentry->d_lock); + dir = d_inode(dentry->d_parent); + lease->ino = cpu_to_le64(ceph_ino(dir)); + lease->first = lease->last = cpu_to_le64(ceph_snap(dir)); + + put_unaligned_le32(dentry->d_name.len, lease + 1); + memcpy((void *)(lease + 1) + 4, + dentry->d_name.name, dentry->d_name.len); + spin_unlock(&dentry->d_lock); + /* + * 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); +} + +/* + * lock unlock the session, to wait ongoing session activities + */ +static void lock_unlock_session(struct ceph_mds_session *s) +{ + mutex_lock(&s->s_mutex); + mutex_unlock(&s->s_mutex); +} + +static void maybe_recover_session(struct ceph_mds_client *mdsc) +{ + struct ceph_fs_client *fsc = mdsc->fsc; + + if (!ceph_test_mount_opt(fsc, CLEANRECOVER)) + return; + + if (READ_ONCE(fsc->mount_state) != CEPH_MOUNT_MOUNTED) + return; + + if (!READ_ONCE(fsc->blocklisted)) + return; + + if (fsc->last_auto_reconnect && + time_before(jiffies, fsc->last_auto_reconnect + HZ * 60 * 30)) + return; + + pr_info("auto reconnect after blocklisted\n"); + fsc->last_auto_reconnect = jiffies; + ceph_force_reconnect(fsc->sb); +} + +bool check_session_state(struct ceph_mds_session *s) +{ + switch (s->s_state) { + case CEPH_MDS_SESSION_OPEN: + if (s->s_ttl && time_after(jiffies, s->s_ttl)) { + s->s_state = CEPH_MDS_SESSION_HUNG; + pr_info("mds%d hung\n", s->s_mds); + } + break; + case CEPH_MDS_SESSION_CLOSING: + /* Should never reach this when we're unmounting */ + WARN_ON_ONCE(s->s_ttl); + fallthrough; + case CEPH_MDS_SESSION_NEW: + case CEPH_MDS_SESSION_RESTARTING: + case CEPH_MDS_SESSION_CLOSED: + case CEPH_MDS_SESSION_REJECTED: + return false; + } + + return true; +} + +/* + * If the sequence is incremented while we're waiting on a REQUEST_CLOSE reply, + * then we need to retransmit that request. + */ +void inc_session_sequence(struct ceph_mds_session *s) +{ + lockdep_assert_held(&s->s_mutex); + + s->s_seq++; + + if (s->s_state == CEPH_MDS_SESSION_CLOSING) { + int ret; + + dout("resending session close request for mds%d\n", s->s_mds); + ret = request_close_session(s); + if (ret < 0) + pr_err("unable to close session to mds%d: %d\n", + s->s_mds, ret); + } +} + +/* + * delayed work -- periodically trim expired leases, renew caps with mds. If + * the @delay parameter is set to 0 or if it's more than 5 secs, the default + * workqueue delay value of 5 secs will be used. + */ +static void schedule_delayed(struct ceph_mds_client *mdsc, unsigned long delay) +{ + unsigned long max_delay = HZ * 5; + + /* 5 secs default delay */ + if (!delay || (delay > max_delay)) + delay = max_delay; + schedule_delayed_work(&mdsc->delayed_work, + round_jiffies_relative(delay)); +} + +static void delayed_work(struct work_struct *work) +{ + struct ceph_mds_client *mdsc = + container_of(work, struct ceph_mds_client, delayed_work.work); + unsigned long delay; + int renew_interval; + int renew_caps; + int i; + + dout("mdsc delayed_work\n"); + + if (mdsc->stopping >= CEPH_MDSC_STOPPING_FLUSHED) + return; + + 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) + continue; + + if (!check_session_state(s)) { + 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); + 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); + + delay = ceph_check_delayed_caps(mdsc); + + ceph_queue_cap_reclaim_work(mdsc); + + ceph_trim_snapid_map(mdsc); + + maybe_recover_session(mdsc); + + schedule_delayed(mdsc, delay); +} + +int ceph_mdsc_init(struct ceph_fs_client *fsc) + +{ + struct ceph_mds_client *mdsc; + int err; + + mdsc = kzalloc(sizeof(struct ceph_mds_client), GFP_NOFS); + if (!mdsc) + return -ENOMEM; + mdsc->fsc = fsc; + mutex_init(&mdsc->mutex); + mdsc->mdsmap = kzalloc(sizeof(*mdsc->mdsmap), GFP_NOFS); + if (!mdsc->mdsmap) { + err = -ENOMEM; + goto err_mdsc; + } + + 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; + atomic64_set(&mdsc->quotarealms_count, 0); + mdsc->quotarealms_inodes = RB_ROOT; + mutex_init(&mdsc->quotarealms_inodes_mutex); + mdsc->last_snap_seq = 0; + init_rwsem(&mdsc->snap_rwsem); + mdsc->snap_realms = RB_ROOT; + INIT_LIST_HEAD(&mdsc->snap_empty); + mdsc->num_snap_realms = 0; + spin_lock_init(&mdsc->snap_empty_lock); + mdsc->last_tid = 0; + mdsc->oldest_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); + INIT_LIST_HEAD(&mdsc->cap_wait_list); + spin_lock_init(&mdsc->cap_delay_lock); + INIT_LIST_HEAD(&mdsc->snap_flush_list); + spin_lock_init(&mdsc->snap_flush_lock); + mdsc->last_cap_flush_tid = 1; + INIT_LIST_HEAD(&mdsc->cap_flush_list); + 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); + INIT_WORK(&mdsc->cap_reclaim_work, ceph_cap_reclaim_work); + atomic_set(&mdsc->cap_reclaim_pending, 0); + err = ceph_metric_init(&mdsc->metric); + if (err) + goto err_mdsmap; + + spin_lock_init(&mdsc->dentry_list_lock); + INIT_LIST_HEAD(&mdsc->dentry_leases); + INIT_LIST_HEAD(&mdsc->dentry_dir_leases); + + ceph_caps_init(mdsc); + ceph_adjust_caps_max_min(mdsc, fsc->mount_options); + + spin_lock_init(&mdsc->snapid_map_lock); + mdsc->snapid_map_tree = RB_ROOT; + INIT_LIST_HEAD(&mdsc->snapid_map_lru); + + init_rwsem(&mdsc->pool_perm_rwsem); + mdsc->pool_perm_tree = RB_ROOT; + + strscpy(mdsc->nodename, utsname()->nodename, + sizeof(mdsc->nodename)); + + fsc->mdsc = mdsc; + return 0; + +err_mdsmap: + kfree(mdsc->mdsmap); +err_mdsc: + kfree(mdsc); + return err; +} + +/* + * 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_options *opts = mdsc->fsc->client->options; + struct ceph_mds_request *req; + + 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, + ceph_timeout_jiffies(opts->mount_timeout)); + + /* 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); + list_del_init(&req->r_wait); + __unregister_request(mdsc, req); + } + } + mutex_unlock(&mdsc->mutex); + dout("wait_requests done\n"); +} + +void send_flush_mdlog(struct ceph_mds_session *s) +{ + struct ceph_msg *msg; + + /* + * Pre-luminous MDS crashes when it sees an unknown session request + */ + if (!CEPH_HAVE_FEATURE(s->s_con.peer_features, SERVER_LUMINOUS)) + return; + + mutex_lock(&s->s_mutex); + dout("request mdlog flush to mds%d (%s)s seq %lld\n", s->s_mds, + ceph_session_state_name(s->s_state), s->s_seq); + msg = ceph_create_session_msg(CEPH_SESSION_REQUEST_FLUSH_MDLOG, + s->s_seq); + if (!msg) { + pr_err("failed to request mdlog flush to mds%d (%s) seq %lld\n", + s->s_mds, ceph_session_state_name(s->s_state), s->s_seq); + } else { + ceph_con_send(&s->s_con, msg); + } + mutex_unlock(&s->s_mutex); +} + +/* + * 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 = CEPH_MDSC_STOPPING_BEGIN; + + ceph_mdsc_iterate_sessions(mdsc, send_flush_mdlog, true); + ceph_mdsc_iterate_sessions(mdsc, lock_unlock_session, false); + 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(); + + ceph_cleanup_quotarealms_inodes(mdsc); +} + +/* + * wait for all write mds requests to flush. + */ +static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid) +{ + struct ceph_mds_request *req = NULL, *nextreq; + struct rb_node *n; + + mutex_lock(&mdsc->mutex); + dout("wait_unsafe_requests want %lld\n", want_tid); +restart: + req = __get_oldest_req(mdsc); + while (req && req->r_tid <= want_tid) { + /* find next request */ + n = rb_next(&req->r_node); + if (n) + nextreq = rb_entry(n, struct ceph_mds_request, r_node); + else + nextreq = NULL; + if (req->r_op != CEPH_MDS_OP_SETFILELOCK && + (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 (READ_ONCE(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->last_cap_flush_tid; + if (!list_empty(&mdsc->cap_flush_list)) { + struct ceph_cap_flush *cf = + list_last_entry(&mdsc->cap_flush_list, + struct ceph_cap_flush, g_list); + cf->wake = true; + } + 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, int skipped) +{ + if (READ_ONCE(mdsc->fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) + return true; + return atomic_read(&mdsc->num_sessions) <= skipped; +} + +/* + * called after sb is ro. + */ +void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc) +{ + struct ceph_options *opts = mdsc->fsc->client->options; + struct ceph_mds_session *session; + int i; + int skipped = 0; + + 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); + if (__close_session(mdsc, session) <= 0) + skipped++; + 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, skipped), + ceph_timeout_jiffies(opts->mount_timeout)); + + /* tear down remaining sessions */ + mutex_lock(&mdsc->mutex); + for (i = 0; i < mdsc->max_sessions; i++) { + if (mdsc->sessions[i]) { + session = ceph_get_mds_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_snapid_map(mdsc); + ceph_cleanup_empty_realms(mdsc); + + cancel_work_sync(&mdsc->cap_reclaim_work); + cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */ + + dout("stopped\n"); +} + +void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc) +{ + struct ceph_mds_session *session; + int mds; + + dout("force umount\n"); + + mutex_lock(&mdsc->mutex); + for (mds = 0; mds < mdsc->max_sessions; mds++) { + session = __ceph_lookup_mds_session(mdsc, mds); + if (!session) + continue; + + if (session->s_state == CEPH_MDS_SESSION_REJECTED) + __unregister_session(mdsc, session); + __wake_requests(mdsc, &session->s_waiting); + mutex_unlock(&mdsc->mutex); + + mutex_lock(&session->s_mutex); + __close_session(mdsc, session); + if (session->s_state == CEPH_MDS_SESSION_CLOSING) { + cleanup_session_requests(mdsc, session); + remove_session_caps(session); + } + mutex_unlock(&session->s_mutex); + ceph_put_mds_session(session); + + mutex_lock(&mdsc->mutex); + kick_requests(mdsc, mds); + } + __wake_requests(mdsc, &mdsc->waiting_for_map); + mutex_unlock(&mdsc->mutex); +} + +static void ceph_mdsc_stop(struct ceph_mds_client *mdsc) +{ + dout("stop\n"); + /* + * Make sure the delayed work stopped before releasing + * the resources. + * + * Because the cancel_delayed_work_sync() will only + * guarantee that the work finishes executing. But the + * delayed work will re-arm itself again after that. + */ + flush_delayed_work(&mdsc->delayed_work); + + if (mdsc->mdsmap) + ceph_mdsmap_destroy(mdsc->mdsmap); + kfree(mdsc->sessions); + ceph_caps_finalize(mdsc); + ceph_pool_perm_destroy(mdsc); +} + +void ceph_mdsc_destroy(struct ceph_fs_client *fsc) +{ + struct ceph_mds_client *mdsc = fsc->mdsc; + dout("mdsc_destroy %p\n", mdsc); + + if (!mdsc) + return; + + /* flush out any connection work with references to us */ + ceph_msgr_flush(); + + ceph_mdsc_stop(mdsc); + + ceph_metric_destroy(&mdsc->metric); + + fsc->mdsc = NULL; + kfree(mdsc); + dout("mdsc_destroy %p done\n", mdsc); +} + +void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc, struct ceph_msg *msg) +{ + struct ceph_fs_client *fsc = mdsc->fsc; + const char *mds_namespace = fsc->mount_options->mds_namespace; + void *p = msg->front.iov_base; + void *end = p + msg->front.iov_len; + u32 epoch; + u32 map_len; + u32 num_fs; + u32 mount_fscid = (u32)-1; + u8 struct_v, struct_cv; + int err = -EINVAL; + + ceph_decode_need(&p, end, sizeof(u32), bad); + epoch = ceph_decode_32(&p); + + dout("handle_fsmap epoch %u\n", epoch); + + ceph_decode_need(&p, end, 2 + sizeof(u32), bad); + struct_v = ceph_decode_8(&p); + struct_cv = ceph_decode_8(&p); + map_len = ceph_decode_32(&p); + + ceph_decode_need(&p, end, sizeof(u32) * 3, bad); + p += sizeof(u32) * 2; /* skip epoch and legacy_client_fscid */ + + num_fs = ceph_decode_32(&p); + while (num_fs-- > 0) { + void *info_p, *info_end; + u32 info_len; + u8 info_v, info_cv; + u32 fscid, namelen; + + ceph_decode_need(&p, end, 2 + sizeof(u32), bad); + info_v = ceph_decode_8(&p); + info_cv = ceph_decode_8(&p); + info_len = ceph_decode_32(&p); + ceph_decode_need(&p, end, info_len, bad); + info_p = p; + info_end = p + info_len; + p = info_end; + + ceph_decode_need(&info_p, info_end, sizeof(u32) * 2, bad); + fscid = ceph_decode_32(&info_p); + namelen = ceph_decode_32(&info_p); + ceph_decode_need(&info_p, info_end, namelen, bad); + + if (mds_namespace && + strlen(mds_namespace) == namelen && + !strncmp(mds_namespace, (char *)info_p, namelen)) { + mount_fscid = fscid; + break; + } + } + + ceph_monc_got_map(&fsc->client->monc, CEPH_SUB_FSMAP, epoch); + if (mount_fscid != (u32)-1) { + fsc->client->monc.fs_cluster_id = mount_fscid; + ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_MDSMAP, + 0, true); + ceph_monc_renew_subs(&fsc->client->monc); + } else { + err = -ENOENT; + goto err_out; + } + return; + +bad: + pr_err("error decoding fsmap\n"); +err_out: + mutex_lock(&mdsc->mutex); + mdsc->mdsmap_err = err; + __wake_requests(mdsc, &mdsc->waiting_for_map); + mutex_unlock(&mdsc->mutex); +} + +/* + * handle mds map update. + */ +void ceph_mdsc_handle_mdsmap(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? */ + 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->max_file_size = min((loff_t)mdsc->mdsmap->m_max_file_size, + MAX_LFS_FILESIZE); + + __wake_requests(mdsc, &mdsc->waiting_for_map); + ceph_monc_got_map(&mdsc->fsc->client->monc, CEPH_SUB_MDSMAP, + mdsc->mdsmap->m_epoch); + + mutex_unlock(&mdsc->mutex); + schedule_delayed(mdsc, 0); + 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 (ceph_get_mds_session(s)) + return con; + return NULL; +} + +static void con_put(struct ceph_connection *con) +{ + struct ceph_mds_session *s = con->private; + + 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_mdsmap(mdsc, msg); + break; + case CEPH_MSG_FS_MAP_USER: + ceph_mdsc_handle_fsmap(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; + case CEPH_MSG_CLIENT_QUOTA: + ceph_handle_quota(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(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 add_authorizer_challenge(struct ceph_connection *con, + void *challenge_buf, int challenge_buf_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_add_authorizer_challenge(ac, s->s_auth.authorizer, + challenge_buf, challenge_buf_len); +} + +static int verify_authorizer_reply(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; + + return ceph_auth_verify_authorizer_reply(ac, s->s_auth.authorizer); +} + +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 mds_sign_message(struct ceph_msg *msg) +{ + struct ceph_mds_session *s = msg->con->private; + struct ceph_auth_handshake *auth = &s->s_auth; + + return ceph_auth_sign_message(auth, msg); +} + +static int mds_check_message_signature(struct ceph_msg *msg) +{ + struct ceph_mds_session *s = msg->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, + .add_authorizer_challenge = add_authorizer_challenge, + .verify_authorizer_reply = verify_authorizer_reply, + .invalidate_authorizer = invalidate_authorizer, + .peer_reset = peer_reset, + .alloc_msg = mds_alloc_msg, + .sign_message = mds_sign_message, + .check_message_signature = mds_check_message_signature, +}; + +/* eof */ |