diff options
Diffstat (limited to 'fs/ceph/quota.c')
| -rw-r--r-- | fs/ceph/quota.c | 535 |
1 files changed, 535 insertions, 0 deletions
diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c new file mode 100644 index 000000000..f7fcf7f08 --- /dev/null +++ b/fs/ceph/quota.c @@ -0,0 +1,535 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * quota.c - CephFS quota + * + * Copyright (C) 2017-2018 SUSE + */ + +#include <linux/statfs.h> + +#include "super.h" +#include "mds_client.h" + +void ceph_adjust_quota_realms_count(struct inode *inode, bool inc) +{ + struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(inode->i_sb); + if (inc) + atomic64_inc(&mdsc->quotarealms_count); + else + atomic64_dec(&mdsc->quotarealms_count); +} + +static inline bool ceph_has_realms_with_quotas(struct inode *inode) +{ + struct super_block *sb = inode->i_sb; + struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(sb); + struct inode *root = d_inode(sb->s_root); + + if (atomic64_read(&mdsc->quotarealms_count) > 0) + return true; + /* if root is the real CephFS root, we don't have quota realms */ + if (root && ceph_ino(root) == CEPH_INO_ROOT) + return false; + /* MDS stray dirs have no quota realms */ + if (ceph_vino_is_reserved(ceph_inode(inode)->i_vino)) + return false; + /* otherwise, we can't know for sure */ + return true; +} + +void ceph_handle_quota(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session, + struct ceph_msg *msg) +{ + struct super_block *sb = mdsc->fsc->sb; + struct ceph_mds_quota *h = msg->front.iov_base; + struct ceph_vino vino; + struct inode *inode; + struct ceph_inode_info *ci; + + if (!ceph_inc_mds_stopping_blocker(mdsc, session)) + return; + + if (msg->front.iov_len < sizeof(*h)) { + pr_err("%s corrupt message mds%d len %d\n", __func__, + session->s_mds, (int)msg->front.iov_len); + ceph_msg_dump(msg); + goto out; + } + + /* lookup inode */ + vino.ino = le64_to_cpu(h->ino); + vino.snap = CEPH_NOSNAP; + inode = ceph_find_inode(sb, vino); + if (!inode) { + pr_warn("Failed to find inode %llu\n", vino.ino); + goto out; + } + ci = ceph_inode(inode); + + spin_lock(&ci->i_ceph_lock); + ci->i_rbytes = le64_to_cpu(h->rbytes); + ci->i_rfiles = le64_to_cpu(h->rfiles); + ci->i_rsubdirs = le64_to_cpu(h->rsubdirs); + __ceph_update_quota(ci, le64_to_cpu(h->max_bytes), + le64_to_cpu(h->max_files)); + spin_unlock(&ci->i_ceph_lock); + + iput(inode); +out: + ceph_dec_mds_stopping_blocker(mdsc); +} + +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 && ceph_is_any_caps(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; + } + if (qri->inode) { + /* get caps */ + int ret = __ceph_do_getattr(qri->inode, NULL, + CEPH_STAT_CAP_INODE, true); + if (ret >= 0) + in = qri->inode; + else + in = ERR_PTR(ret); + } else { + in = ceph_lookup_inode(sb, realm->ino); + } + + if (IS_ERR(in)) { + dout("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 (max_files, + * max_bytes, or any, depending on the 'which_quota' argument). If the root is + * reached, return the root ceph_snap_realm instead. + * + * 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, + enum quota_get_realm which_quota, + bool retry) +{ + struct ceph_inode_info *ci = NULL; + struct ceph_snap_realm *realm, *next; + struct inode *in; + bool has_quota; + + if (ceph_snap(inode) != CEPH_NOSNAP) + return NULL; + +restart: + realm = ceph_inode(inode)->i_snap_realm; + if (realm) + ceph_get_snap_realm(mdsc, realm); + else + 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); + has_inode = realm->inode; + in = has_inode ? igrab(realm->inode) : NULL; + spin_unlock(&realm->inodes_with_caps_lock); + 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_quota(ci, which_quota); + iput(in); + + next = realm->parent; + if (has_quota || !next) + return realm; + + ceph_get_snap_realm(mdsc, next); + ceph_put_snap_realm(mdsc, realm); + realm = next; + } + if (realm) + ceph_put_snap_realm(mdsc, realm); + + return NULL; +} + +bool ceph_quota_is_same_realm(struct inode *old, struct inode *new) +{ + struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(old->i_sb); + 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, QUOTA_GET_ANY, true); + new_realm = get_quota_realm(mdsc, new, QUOTA_GET_ANY, 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); + + if (old_realm) + ceph_put_snap_realm(mdsc, old_realm); + if (new_realm) + ceph_put_snap_realm(mdsc, new_realm); + + return is_same; +} + +enum quota_check_op { + QUOTA_CHECK_MAX_FILES_OP, /* check quota max_files limit */ + QUOTA_CHECK_MAX_BYTES_OP, /* check quota max_files limit */ + QUOTA_CHECK_MAX_BYTES_APPROACHING_OP /* check if quota max_files + limit is approaching */ +}; + +/* + * check_quota_exceeded() will walk up the snaprealm hierarchy and, for each + * realm, it will execute quota check operation defined by the 'op' parameter. + * The snaprealm walk is interrupted if the quota check detects that the quota + * is exceeded or if the root inode is reached. + */ +static bool check_quota_exceeded(struct inode *inode, enum quota_check_op op, + loff_t delta) +{ + struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(inode->i_sb); + struct ceph_inode_info *ci; + struct ceph_snap_realm *realm, *next; + struct inode *in; + u64 max, rvalue; + bool exceeded = false; + + if (ceph_snap(inode) != CEPH_NOSNAP) + return false; + + down_read(&mdsc->snap_rwsem); +restart: + realm = ceph_inode(inode)->i_snap_realm; + if (realm) + ceph_get_snap_realm(mdsc, realm); + else + 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); + has_inode = realm->inode; + in = has_inode ? igrab(realm->inode) : NULL; + spin_unlock(&realm->inodes_with_caps_lock); + 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) { + max = ci->i_max_files; + rvalue = ci->i_rfiles + ci->i_rsubdirs; + } else { + max = ci->i_max_bytes; + rvalue = ci->i_rbytes; + } + spin_unlock(&ci->i_ceph_lock); + switch (op) { + case QUOTA_CHECK_MAX_FILES_OP: + case QUOTA_CHECK_MAX_BYTES_OP: + exceeded = (max && (rvalue + delta > max)); + break; + case QUOTA_CHECK_MAX_BYTES_APPROACHING_OP: + if (max) { + if (rvalue >= max) + exceeded = true; + else { + /* + * when we're writing more that 1/16th + * of the available space + */ + exceeded = + (((max - rvalue) >> 4) < delta); + } + } + break; + default: + /* Shouldn't happen */ + pr_warn("Invalid quota check op (%d)\n", op); + exceeded = true; /* Just break the loop */ + } + iput(in); + + next = realm->parent; + if (exceeded || !next) + break; + ceph_get_snap_realm(mdsc, next); + ceph_put_snap_realm(mdsc, realm); + realm = next; + } + if (realm) + ceph_put_snap_realm(mdsc, realm); + up_read(&mdsc->snap_rwsem); + + return exceeded; +} + +/* + * ceph_quota_is_max_files_exceeded - check if we can create a new file + * @inode: directory where a new file is being created + * + * This functions returns true is max_files quota allows a new file to be + * created. It is necessary to walk through the snaprealm hierarchy (until the + * FS root) to check all realms with quotas set. + */ +bool ceph_quota_is_max_files_exceeded(struct inode *inode) +{ + if (!ceph_has_realms_with_quotas(inode)) + return false; + + WARN_ON(!S_ISDIR(inode->i_mode)); + + return check_quota_exceeded(inode, QUOTA_CHECK_MAX_FILES_OP, 1); +} + +/* + * ceph_quota_is_max_bytes_exceeded - check if we can write to a file + * @inode: inode being written + * @newsize: new size if write succeeds + * + * This functions returns true is max_bytes quota allows a file size to reach + * @newsize; it returns false otherwise. + */ +bool ceph_quota_is_max_bytes_exceeded(struct inode *inode, loff_t newsize) +{ + loff_t size = i_size_read(inode); + + if (!ceph_has_realms_with_quotas(inode)) + return false; + + /* return immediately if we're decreasing file size */ + if (newsize <= size) + return false; + + return check_quota_exceeded(inode, QUOTA_CHECK_MAX_BYTES_OP, (newsize - size)); +} + +/* + * ceph_quota_is_max_bytes_approaching - check if we're reaching max_bytes + * @inode: inode being written + * @newsize: new size if write succeeds + * + * This function returns true if the new file size @newsize will be consuming + * more than 1/16th of the available quota space; it returns false otherwise. + */ +bool ceph_quota_is_max_bytes_approaching(struct inode *inode, loff_t newsize) +{ + loff_t size = ceph_inode(inode)->i_reported_size; + + if (!ceph_has_realms_with_quotas(inode)) + return false; + + /* return immediately if we're decreasing file size */ + if (newsize <= size) + return false; + + return check_quota_exceeded(inode, QUOTA_CHECK_MAX_BYTES_APPROACHING_OP, + (newsize - size)); +} + +/* + * ceph_quota_update_statfs - if root has quota update statfs with quota status + * @fsc: filesystem client instance + * @buf: statfs to update + * + * If the mounted filesystem root has max_bytes quota set, update the filesystem + * statistics with the quota status. + * + * This function returns true if the stats have been updated, false otherwise. + */ +bool ceph_quota_update_statfs(struct ceph_fs_client *fsc, struct kstatfs *buf) +{ + struct ceph_mds_client *mdsc = fsc->mdsc; + struct ceph_inode_info *ci; + struct ceph_snap_realm *realm; + struct inode *in; + u64 total = 0, used, free; + bool is_updated = false; + + down_read(&mdsc->snap_rwsem); + realm = get_quota_realm(mdsc, d_inode(fsc->sb->s_root), + QUOTA_GET_MAX_BYTES, true); + up_read(&mdsc->snap_rwsem); + if (!realm) + return false; + + spin_lock(&realm->inodes_with_caps_lock); + in = realm->inode ? igrab(realm->inode) : NULL; + spin_unlock(&realm->inodes_with_caps_lock); + if (in) { + ci = ceph_inode(in); + spin_lock(&ci->i_ceph_lock); + if (ci->i_max_bytes) { + total = ci->i_max_bytes >> CEPH_BLOCK_SHIFT; + used = ci->i_rbytes >> CEPH_BLOCK_SHIFT; + /* For quota size less than 4MB, use 4KB block size */ + if (!total) { + total = ci->i_max_bytes >> CEPH_4K_BLOCK_SHIFT; + used = ci->i_rbytes >> CEPH_4K_BLOCK_SHIFT; + buf->f_frsize = 1 << CEPH_4K_BLOCK_SHIFT; + } + /* It is possible for a quota to be exceeded. + * Report 'zero' in that case + */ + free = total > used ? total - used : 0; + /* For quota size less than 4KB, report the + * total=used=4KB,free=0 when quota is full + * and total=free=4KB, used=0 otherwise */ + if (!total) { + total = 1; + free = ci->i_max_bytes > ci->i_rbytes ? 1 : 0; + buf->f_frsize = 1 << CEPH_4K_BLOCK_SHIFT; + } + } + spin_unlock(&ci->i_ceph_lock); + if (total) { + buf->f_blocks = total; + buf->f_bfree = free; + buf->f_bavail = free; + is_updated = true; + } + iput(in); + } + ceph_put_snap_realm(mdsc, realm); + + return is_updated; +} + |