From b7a2921765cf796280baf653a52b22b52e0ba266 Mon Sep 17 00:00:00 2001 From: Luis Henriques Date: Fri, 5 Jan 2018 10:47:19 +0000 Subject: [PATCH] ceph: quota: support for ceph.quota.max_files This patch adds support for the max_files quota. It hooks into all the ceph functions that add new filesystem objects that need to be checked against the quota limits. When these limits are hit, -EDQUOT is returned. Note that we're not checking quotas on ceph_link(). ceph_link doesn't really create a new inode, and since the MDS doesn't update the directory statistics when a new (hard) link is created (only with symlinks), they are not accounted as a new file. Signed-off-by: Luis Henriques Reviewed-by: "Yan, Zheng" Signed-off-by: Ilya Dryomov --- fs/ceph/dir.c | 11 ++++++++ fs/ceph/file.c | 4 ++- fs/ceph/quota.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/ceph/super.h | 1 + 4 files changed, 95 insertions(+), 1 deletion(-) diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c index 16405e0..7d9851c 100644 --- a/fs/ceph/dir.c +++ b/fs/ceph/dir.c @@ -828,6 +828,9 @@ static int ceph_mknod(struct inode *dir, struct dentry *dentry, if (ceph_snap(dir) != CEPH_NOSNAP) return -EROFS; + if (ceph_quota_is_max_files_exceeded(dir)) + return -EDQUOT; + err = ceph_pre_init_acls(dir, &mode, &acls); if (err < 0) return err; @@ -881,6 +884,9 @@ static int ceph_symlink(struct inode *dir, struct dentry *dentry, if (ceph_snap(dir) != CEPH_NOSNAP) return -EROFS; + if (ceph_quota_is_max_files_exceeded(dir)) + return -EDQUOT; + dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest); req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS); if (IS_ERR(req)) { @@ -930,6 +936,11 @@ static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) goto out; } + if (ceph_quota_is_max_files_exceeded(dir)) { + err = -EDQUOT; + goto out; + } + mode |= S_IFDIR; err = ceph_pre_init_acls(dir, &mode, &acls); if (err < 0) diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 4a92acb..c304233 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -402,7 +402,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry, struct ceph_mds_request *req; struct dentry *dn; struct ceph_acls_info acls = {}; - int mask; + int mask; int err; dout("atomic_open %p dentry %p '%pd' %s flags %d mode 0%o\n", @@ -413,6 +413,8 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry, return -ENAMETOOLONG; if (flags & O_CREAT) { + if (ceph_quota_is_max_files_exceeded(dir)) + return -EDQUOT; err = ceph_pre_init_acls(dir, &mode, &acls); if (err < 0) return err; diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c index 1b69d83..cf1c78c 100644 --- a/fs/ceph/quota.c +++ b/fs/ceph/quota.c @@ -63,3 +63,83 @@ void ceph_handle_quota(struct ceph_mds_client *mdsc, iput(inode); } + +enum quota_check_op { + QUOTA_CHECK_MAX_FILES_OP /* check quota max_files limit */ +}; + +/* + * 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 ceph_vino vino; + struct inode *in; + u64 max, rvalue; + bool is_root; + bool exceeded = false; + + down_read(&mdsc->snap_rwsem); + realm = ceph_inode(inode)->i_snap_realm; + ceph_get_snap_realm(mdsc, realm); + while (realm) { + vino.ino = realm->ino; + vino.snap = CEPH_NOSNAP; + in = ceph_find_inode(inode->i_sb, vino); + if (!in) { + pr_warn("Failed to find inode for %llu\n", vino.ino); + 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; + } + is_root = (ci->i_vino.ino == CEPH_INO_ROOT); + spin_unlock(&ci->i_ceph_lock); + switch (op) { + case QUOTA_CHECK_MAX_FILES_OP: + exceeded = (max && (rvalue >= max)); + break; + default: + /* Shouldn't happen */ + pr_warn("Invalid quota check op (%d)\n", op); + exceeded = true; /* Just break the loop */ + } + iput(in); + + if (is_root || exceeded) + break; + next = realm->parent; + 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) +{ + WARN_ON(!S_ISDIR(inode->i_mode)); + + return check_quota_exceeded(inode, QUOTA_CHECK_MAX_FILES_OP, 0); +} diff --git a/fs/ceph/super.h b/fs/ceph/super.h index 0c95a92..4afc6cc 100644 --- a/fs/ceph/super.h +++ b/fs/ceph/super.h @@ -1077,5 +1077,6 @@ extern void ceph_fs_debugfs_cleanup(struct ceph_fs_client *client); extern void ceph_handle_quota(struct ceph_mds_client *mdsc, struct ceph_mds_session *session, struct ceph_msg *msg); +extern bool ceph_quota_is_max_files_exceeded(struct inode *inode); #endif /* _FS_CEPH_SUPER_H */ -- 2.7.4