diff options
author | Yan, Zheng <zyan@redhat.com> | 2017-12-14 10:11:09 +0300 |
---|---|---|
committer | Ilya Dryomov <idryomov@gmail.com> | 2019-03-05 20:55:16 +0300 |
commit | 75c9627efb7288e1725e9903ea275cc6b5992f17 (patch) | |
tree | 065ca7fbb792935029bc5c94875ead92cca81b9e /fs | |
parent | 81c5a1487e52a316e5e7d79e9911376648a79e85 (diff) | |
download | linux-75c9627efb7288e1725e9903ea275cc6b5992f17.tar.xz |
ceph: map snapid to anonymous bdev ID
ceph_getattr() return zero dev ID for head inodes and set dev ID to
snapid directly for snaphost inodes. This is not good because userspace
utilities may consider device ID of 0 as invalid, snapid may conflict
with other device's ID.
This patch introduces "snapids to anonymous bdev IDs" map. we create a
new mapping when we see a snapid for the first time. we trim unused
mapping after it is ilde for 5 minutes.
Link: http://tracker.ceph.com/issues/22353
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/ceph/inode.c | 37 | ||||
-rw-r--r-- | fs/ceph/mds_client.c | 8 | ||||
-rw-r--r-- | fs/ceph/mds_client.h | 13 | ||||
-rw-r--r-- | fs/ceph/snap.c | 156 | ||||
-rw-r--r-- | fs/ceph/super.h | 13 |
5 files changed, 210 insertions, 17 deletions
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c index c080b133c08b..7f82ceff510a 100644 --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -548,17 +548,22 @@ void ceph_destroy_inode(struct inode *inode) */ if (ci->i_snap_realm) { struct ceph_mds_client *mdsc = - ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc; - struct ceph_snap_realm *realm = ci->i_snap_realm; - - dout(" dropping residual ref to snap realm %p\n", realm); - spin_lock(&realm->inodes_with_caps_lock); - list_del_init(&ci->i_snap_realm_item); - ci->i_snap_realm = NULL; - if (realm->ino == ci->i_vino.ino) - realm->inode = NULL; - spin_unlock(&realm->inodes_with_caps_lock); - ceph_put_snap_realm(mdsc, realm); + ceph_inode_to_client(inode)->mdsc; + if (ceph_snap(inode) == CEPH_NOSNAP) { + struct ceph_snap_realm *realm = ci->i_snap_realm; + dout(" dropping residual ref to snap realm %p\n", + realm); + spin_lock(&realm->inodes_with_caps_lock); + list_del_init(&ci->i_snap_realm_item); + ci->i_snap_realm = NULL; + if (realm->ino == ci->i_vino.ino) + realm->inode = NULL; + spin_unlock(&realm->inodes_with_caps_lock); + ceph_put_snap_realm(mdsc, realm); + } else { + ceph_put_snapid_map(mdsc, ci->i_snapid_map); + ci->i_snap_realm = NULL; + } } kfree(ci->i_symlink); @@ -776,6 +781,9 @@ static int fill_inode(struct inode *inode, struct page *locked_page, pool_ns = ceph_find_or_create_string(iinfo->pool_ns_data, iinfo->pool_ns_len); + if (ceph_snap(inode) != CEPH_NOSNAP && !ci->i_snapid_map) + ci->i_snapid_map = ceph_get_snapid_map(mdsc, ceph_snap(inode)); + spin_lock(&ci->i_ceph_lock); /* @@ -2260,10 +2268,11 @@ int ceph_getattr(const struct path *path, struct kstat *stat, if (!err) { generic_fillattr(inode, stat); stat->ino = ceph_translate_ino(inode->i_sb, inode->i_ino); - if (ceph_snap(inode) != CEPH_NOSNAP) - stat->dev = ceph_snap(inode); + if (ceph_snap(inode) == CEPH_NOSNAP) + stat->dev = inode->i_sb->s_dev; else - stat->dev = 0; + stat->dev = ci->i_snapid_map ? ci->i_snapid_map->dev : 0; + if (S_ISDIR(inode->i_mode)) { if (ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), RBYTES)) diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index cce4e4b9ea57..f2f57775d2d5 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -3791,6 +3791,8 @@ static void delayed_work(struct work_struct *work) dout("mdsc delayed_work\n"); ceph_check_delayed_caps(mdsc); + ceph_trim_snapid_map(mdsc); + mutex_lock(&mdsc->mutex); renew_interval = mdsc->mdsmap->m_session_timeout >> 2; renew_caps = time_after_eq(jiffies, HZ*renew_interval + @@ -3893,6 +3895,10 @@ int ceph_mdsc_init(struct ceph_fs_client *fsc) ceph_caps_init(mdsc); ceph_adjust_min_caps(mdsc, fsc->min_caps); + 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; @@ -4086,6 +4092,8 @@ void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc) WARN_ON(!list_empty(&mdsc->cap_delay_list)); mutex_unlock(&mdsc->mutex); + ceph_cleanup_snapid_map(mdsc); + ceph_cleanup_empty_realms(mdsc); cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */ diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h index 4f962642fee4..d3a5c4046316 100644 --- a/fs/ceph/mds_client.h +++ b/fs/ceph/mds_client.h @@ -313,6 +313,15 @@ struct ceph_pool_perm { char pool_ns[]; }; +struct ceph_snapid_map { + struct rb_node node; + struct list_head lru; + atomic_t ref; + u64 snap; + dev_t dev; + unsigned long last_used; +}; + /* * mds client state */ @@ -390,6 +399,10 @@ struct ceph_mds_client { struct list_head dentry_lru; int num_dentry; + spinlock_t snapid_map_lock; + struct rb_root snapid_map_tree; + struct list_head snapid_map_lru; + struct rw_semaphore pool_perm_rwsem; struct rb_root pool_perm_tree; diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c index dfc25ceeffed..89aa37fa0f84 100644 --- a/fs/ceph/snap.c +++ b/fs/ceph/snap.c @@ -3,12 +3,13 @@ #include <linux/sort.h> #include <linux/slab.h> - #include "super.h" #include "mds_client.h" - #include <linux/ceph/decode.h> +/* unused map expires after 5 minutes */ +#define CEPH_SNAPID_MAP_TIMEOUT (5 * 60 * HZ) + /* * Snapshots in ceph are driven in large part by cooperation from the * client. In contrast to local file systems or file servers that @@ -989,3 +990,154 @@ out: up_write(&mdsc->snap_rwsem); return; } + +struct ceph_snapid_map* ceph_get_snapid_map(struct ceph_mds_client *mdsc, + u64 snap) +{ + struct ceph_snapid_map *sm, *exist; + struct rb_node **p, *parent; + int ret; + + exist = NULL; + spin_lock(&mdsc->snapid_map_lock); + p = &mdsc->snapid_map_tree.rb_node; + while (*p) { + exist = rb_entry(*p, struct ceph_snapid_map, node); + if (snap > exist->snap) { + p = &(*p)->rb_left; + } else if (snap < exist->snap) { + p = &(*p)->rb_right; + } else { + if (atomic_inc_return(&exist->ref) == 1) + list_del_init(&exist->lru); + break; + } + exist = NULL; + } + spin_unlock(&mdsc->snapid_map_lock); + if (exist) { + dout("found snapid map %llx -> %x\n", exist->snap, exist->dev); + return exist; + } + + sm = kmalloc(sizeof(*sm), GFP_NOFS); + if (!sm) + return NULL; + + ret = get_anon_bdev(&sm->dev); + if (ret < 0) { + kfree(sm); + return NULL; + } + + INIT_LIST_HEAD(&sm->lru); + atomic_set(&sm->ref, 1); + sm->snap = snap; + + exist = NULL; + parent = NULL; + p = &mdsc->snapid_map_tree.rb_node; + spin_lock(&mdsc->snapid_map_lock); + while (*p) { + parent = *p; + exist = rb_entry(*p, struct ceph_snapid_map, node); + if (snap > exist->snap) + p = &(*p)->rb_left; + else if (snap < exist->snap) + p = &(*p)->rb_right; + else + break; + exist = NULL; + } + if (exist) { + if (atomic_inc_return(&exist->ref) == 1) + list_del_init(&exist->lru); + } else { + rb_link_node(&sm->node, parent, p); + rb_insert_color(&sm->node, &mdsc->snapid_map_tree); + } + spin_unlock(&mdsc->snapid_map_lock); + if (exist) { + free_anon_bdev(sm->dev); + kfree(sm); + dout("found snapid map %llx -> %x\n", exist->snap, exist->dev); + return exist; + } + + dout("create snapid map %llx -> %x\n", sm->snap, sm->dev); + return sm; +} + +void ceph_put_snapid_map(struct ceph_mds_client* mdsc, + struct ceph_snapid_map *sm) +{ + if (!sm) + return; + if (atomic_dec_and_lock(&sm->ref, &mdsc->snapid_map_lock)) { + if (!RB_EMPTY_NODE(&sm->node)) { + sm->last_used = jiffies; + list_add_tail(&sm->lru, &mdsc->snapid_map_lru); + spin_unlock(&mdsc->snapid_map_lock); + } else { + /* already cleaned up by + * ceph_cleanup_snapid_map() */ + spin_unlock(&mdsc->snapid_map_lock); + kfree(sm); + } + } +} + +void ceph_trim_snapid_map(struct ceph_mds_client *mdsc) +{ + struct ceph_snapid_map *sm; + unsigned long now; + LIST_HEAD(to_free); + + spin_lock(&mdsc->snapid_map_lock); + now = jiffies; + + while (!list_empty(&mdsc->snapid_map_lru)) { + sm = list_first_entry(&mdsc->snapid_map_lru, + struct ceph_snapid_map, lru); + if (time_after(sm->last_used + CEPH_SNAPID_MAP_TIMEOUT, now)) + break; + + rb_erase(&sm->node, &mdsc->snapid_map_tree); + list_move(&sm->lru, &to_free); + } + spin_unlock(&mdsc->snapid_map_lock); + + while (!list_empty(&to_free)) { + sm = list_first_entry(&to_free, struct ceph_snapid_map, lru); + list_del(&sm->lru); + dout("trim snapid map %llx -> %x\n", sm->snap, sm->dev); + free_anon_bdev(sm->dev); + kfree(sm); + } +} + +void ceph_cleanup_snapid_map(struct ceph_mds_client *mdsc) +{ + struct ceph_snapid_map *sm; + struct rb_node *p; + LIST_HEAD(to_free); + + spin_lock(&mdsc->snapid_map_lock); + while ((p = rb_first(&mdsc->snapid_map_tree))) { + sm = rb_entry(p, struct ceph_snapid_map, node); + rb_erase(p, &mdsc->snapid_map_tree); + RB_CLEAR_NODE(p); + list_move(&sm->lru, &to_free); + } + spin_unlock(&mdsc->snapid_map_lock); + + while (!list_empty(&to_free)) { + sm = list_first_entry(&to_free, struct ceph_snapid_map, lru); + list_del(&sm->lru); + free_anon_bdev(sm->dev); + if (WARN_ON_ONCE(atomic_read(&sm->ref))) { + pr_err("snapid map %llx -> %x still in use\n", + sm->snap, sm->dev); + } + } +} diff --git a/fs/ceph/super.h b/fs/ceph/super.h index dfb64a5211b6..5b15ae91024a 100644 --- a/fs/ceph/super.h +++ b/fs/ceph/super.h @@ -370,7 +370,10 @@ struct ceph_inode_info { struct list_head i_unsafe_iops; /* uncommitted mds inode ops */ spinlock_t i_unsafe_lock; - struct ceph_snap_realm *i_snap_realm; /* snap realm (if caps) */ + union { + struct ceph_snap_realm *i_snap_realm; /* snap realm (if caps) */ + struct ceph_snapid_map *i_snapid_map; /* snapid -> dev_t */ + }; int i_snap_realm_counter; /* snap realm (if caps) */ struct list_head i_snap_realm_item; struct list_head i_snap_flush_item; @@ -837,6 +840,14 @@ extern int __ceph_finish_cap_snap(struct ceph_inode_info *ci, struct ceph_cap_snap *capsnap); extern void ceph_cleanup_empty_realms(struct ceph_mds_client *mdsc); +extern struct ceph_snapid_map *ceph_get_snapid_map(struct ceph_mds_client *mdsc, + u64 snap); +extern void ceph_put_snapid_map(struct ceph_mds_client* mdsc, + struct ceph_snapid_map *sm); +extern void ceph_trim_snapid_map(struct ceph_mds_client *mdsc); +extern void ceph_cleanup_snapid_map(struct ceph_mds_client *mdsc); + + /* * a cap_snap is "pending" if it is still awaiting an in-progress * sync write (that may/may not still update size, mtime, etc.). |