diff options
Diffstat (limited to 'fs/ceph/quota.c')
| -rw-r--r-- | fs/ceph/quota.c | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c new file mode 100644 index 000000000000..242bfa5c0539 --- /dev/null +++ b/fs/ceph/quota.c @@ -0,0 +1,361 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * quota.c - CephFS quota + * + * Copyright (C) 2017-2018 SUSE + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#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_inode_to_client(inode)->mdsc; + 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 ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc; + return atomic64_read(&mdsc->quotarealms_count) > 0; +} + +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 (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); + return; + } + + /* increment msg sequence number */ + mutex_lock(&session->s_mutex); + session->s_seq++; + mutex_unlock(&session->s_mutex); + + /* 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); + return; + } + 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); +} + +/* + * 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 + * or max_bytes). 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. + */ +static struct ceph_snap_realm *get_quota_realm(struct ceph_mds_client *mdsc, + struct inode *inode) +{ + 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; + + 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) { + spin_lock(&realm->inodes_with_caps_lock); + in = realm->inode ? igrab(realm->inode) : NULL; + spin_unlock(&realm->inodes_with_caps_lock); + if (!in) + break; + + ci = ceph_inode(in); + has_quota = __ceph_has_any_quota(ci); + 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_inode_to_client(old)->mdsc; + struct ceph_snap_realm *old_realm, *new_realm; + bool is_same; + + down_read(&mdsc->snap_rwsem); + old_realm = get_quota_realm(mdsc, old); + new_realm = get_quota_realm(mdsc, new); + 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_inode_to_client(inode)->mdsc; + 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); + 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) { + spin_lock(&realm->inodes_with_caps_lock); + in = realm->inode ? igrab(realm->inode) : NULL; + spin_unlock(&realm->inodes_with_caps_lock); + if (!in) + break; + + 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: + exceeded = (max && (rvalue >= max)); + break; + 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; + } + 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, 0); +} + +/* + * 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)); + 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; + /* It is possible for a quota to be exceeded. + * Report 'zero' in that case + */ + free = total > used ? total - used : 0; + } + 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; +} + |