diff options
| -rw-r--r-- | fs/ceph/mds_client.c | 4 | ||||
| -rw-r--r-- | fs/ceph/mds_client.h | 18 | ||||
| -rw-r--r-- | fs/ceph/quota.c | 177 | ||||
| -rw-r--r-- | fs/ceph/super.h | 1 |
4 files changed, 190 insertions, 10 deletions
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index 9049c2a3e972..5dee98b4cfde 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -4125,6 +4125,8 @@ int ceph_mdsc_init(struct ceph_fs_client *fsc) 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; @@ -4216,6 +4218,8 @@ void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc) * their inode/dcache refs */ ceph_msgr_flush(); + + ceph_cleanup_quotarealms_inodes(mdsc); } /* diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h index 50385a481fdb..3f0029aa8a39 100644 --- a/fs/ceph/mds_client.h +++ b/fs/ceph/mds_client.h @@ -326,6 +326,18 @@ struct ceph_snapid_map { }; /* + * node for list of quotarealm inodes that are not visible from the filesystem + * mountpoint, but required to handle, e.g. quotas. + */ +struct ceph_quotarealm_inode { + struct rb_node node; + u64 ino; + unsigned long timeout; /* last time a lookup failed for this inode */ + struct mutex mutex; + struct inode *inode; +}; + +/* * mds client state */ struct ceph_mds_client { @@ -344,6 +356,12 @@ struct ceph_mds_client { int stopping; /* true if shutting down */ atomic64_t quotarealms_count; /* # realms with quota */ + /* + * We keep a list of inodes we don't see in the mountpoint but that we + * need to track quota realms. + */ + struct rb_root quotarealms_inodes; + struct mutex quotarealms_inodes_mutex; /* * snap_rwsem will cover cap linkage into snaprealms, and diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c index 9455d3aef0c3..c4522212872c 100644 --- a/fs/ceph/quota.c +++ b/fs/ceph/quota.c @@ -22,7 +22,16 @@ void ceph_adjust_quota_realms_count(struct inode *inode, bool inc) static inline bool ceph_has_realms_with_quotas(struct inode *inode) { struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc; - return atomic64_read(&mdsc->quotarealms_count) > 0; + struct super_block *sb = mdsc->fsc->sb; + + if (atomic64_read(&mdsc->quotarealms_count) > 0) + return true; + /* if root is the real CephFS root, we don't have quota realms */ + if (sb->s_root->d_inode && + (sb->s_root->d_inode->i_ino == CEPH_INO_ROOT)) + return false; + /* otherwise, we can't know for sure */ + return true; } void ceph_handle_quota(struct ceph_mds_client *mdsc, @@ -68,6 +77,108 @@ void ceph_handle_quota(struct ceph_mds_client *mdsc, iput(inode); } +static struct ceph_quotarealm_inode * +find_quotarealm_inode(struct ceph_mds_client *mdsc, u64 ino) +{ + struct ceph_quotarealm_inode *qri = NULL; + struct rb_node **node, *parent = NULL; + + mutex_lock(&mdsc->quotarealms_inodes_mutex); + node = &(mdsc->quotarealms_inodes.rb_node); + while (*node) { + parent = *node; + qri = container_of(*node, struct ceph_quotarealm_inode, node); + + if (ino < qri->ino) + node = &((*node)->rb_left); + else if (ino > qri->ino) + node = &((*node)->rb_right); + else + break; + } + if (!qri || (qri->ino != ino)) { + /* Not found, create a new one and insert it */ + qri = kmalloc(sizeof(*qri), GFP_KERNEL); + if (qri) { + qri->ino = ino; + qri->inode = NULL; + qri->timeout = 0; + mutex_init(&qri->mutex); + rb_link_node(&qri->node, parent, node); + rb_insert_color(&qri->node, &mdsc->quotarealms_inodes); + } else + pr_warn("Failed to alloc quotarealms_inode\n"); + } + mutex_unlock(&mdsc->quotarealms_inodes_mutex); + + return qri; +} + +/* + * This function will try to lookup a realm inode which isn't visible in the + * filesystem mountpoint. A list of these kind of inodes (not visible) is + * maintained in the mdsc and freed only when the filesystem is umounted. + * + * Note that these inodes are kept in this list even if the lookup fails, which + * allows to prevent useless lookup requests. + */ +static struct inode *lookup_quotarealm_inode(struct ceph_mds_client *mdsc, + struct super_block *sb, + struct ceph_snap_realm *realm) +{ + struct ceph_quotarealm_inode *qri; + struct inode *in; + + qri = find_quotarealm_inode(mdsc, realm->ino); + if (!qri) + return NULL; + + mutex_lock(&qri->mutex); + if (qri->inode) { + /* A request has already returned the inode */ + mutex_unlock(&qri->mutex); + return qri->inode; + } + /* Check if this inode lookup has failed recently */ + if (qri->timeout && + time_before_eq(jiffies, qri->timeout)) { + mutex_unlock(&qri->mutex); + return NULL; + } + in = ceph_lookup_inode(sb, realm->ino); + if (IS_ERR(in)) { + pr_warn("Can't lookup inode %llx (err: %ld)\n", + realm->ino, PTR_ERR(in)); + qri->timeout = jiffies + msecs_to_jiffies(60 * 1000); /* XXX */ + } else { + qri->timeout = 0; + qri->inode = in; + } + mutex_unlock(&qri->mutex); + + return in; +} + +void ceph_cleanup_quotarealms_inodes(struct ceph_mds_client *mdsc) +{ + struct ceph_quotarealm_inode *qri; + struct rb_node *node; + + /* + * It should now be safe to clean quotarealms_inode tree without holding + * mdsc->quotarealms_inodes_mutex... + */ + mutex_lock(&mdsc->quotarealms_inodes_mutex); + while (!RB_EMPTY_ROOT(&mdsc->quotarealms_inodes)) { + node = rb_first(&mdsc->quotarealms_inodes); + qri = rb_entry(node, struct ceph_quotarealm_inode, node); + rb_erase(node, &mdsc->quotarealms_inodes); + iput(qri->inode); + kfree(qri); + } + mutex_unlock(&mdsc->quotarealms_inodes_mutex); +} + /* * This function walks through the snaprealm for an inode and returns the * ceph_snap_realm for the first snaprealm that has quotas set (either max_files @@ -76,9 +187,15 @@ void ceph_handle_quota(struct ceph_mds_client *mdsc, * * Note that the caller is responsible for calling ceph_put_snap_realm() on the * returned realm. + * + * Callers of this function need to hold mdsc->snap_rwsem. However, if there's + * a need to do an inode lookup, this rwsem will be temporarily dropped. Hence + * the 'retry' argument: if rwsem needs to be dropped and 'retry' is 'false' + * this function will return -EAGAIN; otherwise, the snaprealms walk-through + * will be restarted. */ static struct ceph_snap_realm *get_quota_realm(struct ceph_mds_client *mdsc, - struct inode *inode) + struct inode *inode, bool retry) { struct ceph_inode_info *ci = NULL; struct ceph_snap_realm *realm, *next; @@ -88,6 +205,7 @@ static struct ceph_snap_realm *get_quota_realm(struct ceph_mds_client *mdsc, if (ceph_snap(inode) != CEPH_NOSNAP) return NULL; +restart: realm = ceph_inode(inode)->i_snap_realm; if (realm) ceph_get_snap_realm(mdsc, realm); @@ -95,11 +213,25 @@ static struct ceph_snap_realm *get_quota_realm(struct ceph_mds_client *mdsc, pr_err_ratelimited("get_quota_realm: ino (%llx.%llx) " "null i_snap_realm\n", ceph_vinop(inode)); while (realm) { + bool has_inode; + spin_lock(&realm->inodes_with_caps_lock); - in = realm->inode ? igrab(realm->inode) : NULL; + has_inode = realm->inode; + in = has_inode ? igrab(realm->inode) : NULL; spin_unlock(&realm->inodes_with_caps_lock); - if (!in) + if (has_inode && !in) break; + if (!in) { + up_read(&mdsc->snap_rwsem); + in = lookup_quotarealm_inode(mdsc, inode->i_sb, realm); + down_read(&mdsc->snap_rwsem); + if (IS_ERR_OR_NULL(in)) + break; + ceph_put_snap_realm(mdsc, realm); + if (!retry) + return ERR_PTR(-EAGAIN); + goto restart; + } ci = ceph_inode(in); has_quota = __ceph_has_any_quota(ci); @@ -125,9 +257,22 @@ bool ceph_quota_is_same_realm(struct inode *old, struct inode *new) struct ceph_snap_realm *old_realm, *new_realm; bool is_same; +restart: + /* + * We need to lookup 2 quota realms atomically, i.e. with snap_rwsem. + * However, get_quota_realm may drop it temporarily. By setting the + * 'retry' parameter to 'false', we'll get -EAGAIN if the rwsem was + * dropped and we can then restart the whole operation. + */ down_read(&mdsc->snap_rwsem); - old_realm = get_quota_realm(mdsc, old); - new_realm = get_quota_realm(mdsc, new); + old_realm = get_quota_realm(mdsc, old, true); + new_realm = get_quota_realm(mdsc, new, false); + if (PTR_ERR(new_realm) == -EAGAIN) { + up_read(&mdsc->snap_rwsem); + if (old_realm) + ceph_put_snap_realm(mdsc, old_realm); + goto restart; + } is_same = (old_realm == new_realm); up_read(&mdsc->snap_rwsem); @@ -166,6 +311,7 @@ static bool check_quota_exceeded(struct inode *inode, enum quota_check_op op, return false; down_read(&mdsc->snap_rwsem); +restart: realm = ceph_inode(inode)->i_snap_realm; if (realm) ceph_get_snap_realm(mdsc, realm); @@ -173,12 +319,23 @@ static bool check_quota_exceeded(struct inode *inode, enum quota_check_op op, pr_err_ratelimited("check_quota_exceeded: ino (%llx.%llx) " "null i_snap_realm\n", ceph_vinop(inode)); while (realm) { + bool has_inode; + spin_lock(&realm->inodes_with_caps_lock); - in = realm->inode ? igrab(realm->inode) : NULL; + has_inode = realm->inode; + in = has_inode ? igrab(realm->inode) : NULL; spin_unlock(&realm->inodes_with_caps_lock); - if (!in) + if (has_inode && !in) break; - + if (!in) { + up_read(&mdsc->snap_rwsem); + in = lookup_quotarealm_inode(mdsc, inode->i_sb, realm); + down_read(&mdsc->snap_rwsem); + if (IS_ERR_OR_NULL(in)) + break; + ceph_put_snap_realm(mdsc, realm); + goto restart; + } ci = ceph_inode(in); spin_lock(&ci->i_ceph_lock); if (op == QUOTA_CHECK_MAX_FILES_OP) { @@ -314,7 +471,7 @@ bool ceph_quota_update_statfs(struct ceph_fs_client *fsc, struct kstatfs *buf) bool is_updated = false; down_read(&mdsc->snap_rwsem); - realm = get_quota_realm(mdsc, d_inode(fsc->sb->s_root)); + realm = get_quota_realm(mdsc, d_inode(fsc->sb->s_root), true); up_read(&mdsc->snap_rwsem); if (!realm) return false; diff --git a/fs/ceph/super.h b/fs/ceph/super.h index 976f200164f9..a4b0da31d199 100644 --- a/fs/ceph/super.h +++ b/fs/ceph/super.h @@ -1133,5 +1133,6 @@ extern bool ceph_quota_is_max_bytes_approaching(struct inode *inode, loff_t newlen); extern bool ceph_quota_update_statfs(struct ceph_fs_client *fsc, struct kstatfs *buf); +extern void ceph_cleanup_quotarealms_inodes(struct ceph_mds_client *mdsc); #endif /* _FS_CEPH_SUPER_H */ |