diff options
Diffstat (limited to 'kernel/fs/quota/quota.c')
| -rw-r--r-- | kernel/fs/quota/quota.c | 808 |
1 files changed, 808 insertions, 0 deletions
diff --git a/kernel/fs/quota/quota.c b/kernel/fs/quota/quota.c new file mode 100644 index 000000000..86ded7375 --- /dev/null +++ b/kernel/fs/quota/quota.c @@ -0,0 +1,808 @@ +/* + * Quota code necessary even when VFS quota support is not compiled + * into the kernel. The interesting stuff is over in dquot.c, here + * we have symbols for initial quotactl(2) handling, the sysctl(2) + * variables, etc - things needed even when quota support disabled. + */ + +#include <linux/fs.h> +#include <linux/namei.h> +#include <linux/slab.h> +#include <asm/current.h> +#include <linux/uaccess.h> +#include <linux/kernel.h> +#include <linux/security.h> +#include <linux/syscalls.h> +#include <linux/capability.h> +#include <linux/quotaops.h> +#include <linux/types.h> +#include <linux/writeback.h> + +static int check_quotactl_permission(struct super_block *sb, int type, int cmd, + qid_t id) +{ + switch (cmd) { + /* these commands do not require any special privilegues */ + case Q_GETFMT: + case Q_SYNC: + case Q_GETINFO: + case Q_XGETQSTAT: + case Q_XGETQSTATV: + case Q_XQUOTASYNC: + break; + /* allow to query information for dquots we "own" */ + case Q_GETQUOTA: + case Q_XGETQUOTA: + if ((type == USRQUOTA && uid_eq(current_euid(), make_kuid(current_user_ns(), id))) || + (type == GRPQUOTA && in_egroup_p(make_kgid(current_user_ns(), id)))) + break; + /*FALLTHROUGH*/ + default: + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + } + + return security_quotactl(cmd, type, id, sb); +} + +static void quota_sync_one(struct super_block *sb, void *arg) +{ + int type = *(int *)arg; + + if (sb->s_qcop && sb->s_qcop->quota_sync && + (sb->s_quota_types & (1 << type))) + sb->s_qcop->quota_sync(sb, type); +} + +static int quota_sync_all(int type) +{ + int ret; + + if (type >= MAXQUOTAS) + return -EINVAL; + ret = security_quotactl(Q_SYNC, type, 0, NULL); + if (!ret) + iterate_supers(quota_sync_one, &type); + return ret; +} + +unsigned int qtype_enforce_flag(int type) +{ + switch (type) { + case USRQUOTA: + return FS_QUOTA_UDQ_ENFD; + case GRPQUOTA: + return FS_QUOTA_GDQ_ENFD; + case PRJQUOTA: + return FS_QUOTA_PDQ_ENFD; + } + return 0; +} + +static int quota_quotaon(struct super_block *sb, int type, int cmd, qid_t id, + struct path *path) +{ + if (!sb->s_qcop->quota_on && !sb->s_qcop->quota_enable) + return -ENOSYS; + if (sb->s_qcop->quota_enable) + return sb->s_qcop->quota_enable(sb, qtype_enforce_flag(type)); + if (IS_ERR(path)) + return PTR_ERR(path); + return sb->s_qcop->quota_on(sb, type, id, path); +} + +static int quota_quotaoff(struct super_block *sb, int type) +{ + if (!sb->s_qcop->quota_off && !sb->s_qcop->quota_disable) + return -ENOSYS; + if (sb->s_qcop->quota_disable) + return sb->s_qcop->quota_disable(sb, qtype_enforce_flag(type)); + return sb->s_qcop->quota_off(sb, type); +} + +static int quota_getfmt(struct super_block *sb, int type, void __user *addr) +{ + __u32 fmt; + + mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); + if (!sb_has_quota_active(sb, type)) { + mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); + return -ESRCH; + } + fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id; + mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); + if (copy_to_user(addr, &fmt, sizeof(fmt))) + return -EFAULT; + return 0; +} + +static int quota_getinfo(struct super_block *sb, int type, void __user *addr) +{ + struct qc_state state; + struct qc_type_state *tstate; + struct if_dqinfo uinfo; + int ret; + + /* This checks whether qc_state has enough entries... */ + BUILD_BUG_ON(MAXQUOTAS > XQM_MAXQUOTAS); + if (!sb->s_qcop->get_state) + return -ENOSYS; + ret = sb->s_qcop->get_state(sb, &state); + if (ret) + return ret; + tstate = state.s_state + type; + if (!(tstate->flags & QCI_ACCT_ENABLED)) + return -ESRCH; + memset(&uinfo, 0, sizeof(uinfo)); + uinfo.dqi_bgrace = tstate->spc_timelimit; + uinfo.dqi_igrace = tstate->ino_timelimit; + if (tstate->flags & QCI_SYSFILE) + uinfo.dqi_flags |= DQF_SYS_FILE; + if (tstate->flags & QCI_ROOT_SQUASH) + uinfo.dqi_flags |= DQF_ROOT_SQUASH; + uinfo.dqi_valid = IIF_ALL; + if (!ret && copy_to_user(addr, &uinfo, sizeof(uinfo))) + return -EFAULT; + return ret; +} + +static int quota_setinfo(struct super_block *sb, int type, void __user *addr) +{ + struct if_dqinfo info; + struct qc_info qinfo; + + if (copy_from_user(&info, addr, sizeof(info))) + return -EFAULT; + if (!sb->s_qcop->set_info) + return -ENOSYS; + if (info.dqi_valid & ~(IIF_FLAGS | IIF_BGRACE | IIF_IGRACE)) + return -EINVAL; + memset(&qinfo, 0, sizeof(qinfo)); + if (info.dqi_valid & IIF_FLAGS) { + if (info.dqi_flags & ~DQF_SETINFO_MASK) + return -EINVAL; + if (info.dqi_flags & DQF_ROOT_SQUASH) + qinfo.i_flags |= QCI_ROOT_SQUASH; + qinfo.i_fieldmask |= QC_FLAGS; + } + if (info.dqi_valid & IIF_BGRACE) { + qinfo.i_spc_timelimit = info.dqi_bgrace; + qinfo.i_fieldmask |= QC_SPC_TIMER; + } + if (info.dqi_valid & IIF_IGRACE) { + qinfo.i_ino_timelimit = info.dqi_igrace; + qinfo.i_fieldmask |= QC_INO_TIMER; + } + return sb->s_qcop->set_info(sb, type, &qinfo); +} + +static inline qsize_t qbtos(qsize_t blocks) +{ + return blocks << QIF_DQBLKSIZE_BITS; +} + +static inline qsize_t stoqb(qsize_t space) +{ + return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS; +} + +static void copy_to_if_dqblk(struct if_dqblk *dst, struct qc_dqblk *src) +{ + memset(dst, 0, sizeof(*dst)); + dst->dqb_bhardlimit = stoqb(src->d_spc_hardlimit); + dst->dqb_bsoftlimit = stoqb(src->d_spc_softlimit); + dst->dqb_curspace = src->d_space; + dst->dqb_ihardlimit = src->d_ino_hardlimit; + dst->dqb_isoftlimit = src->d_ino_softlimit; + dst->dqb_curinodes = src->d_ino_count; + dst->dqb_btime = src->d_spc_timer; + dst->dqb_itime = src->d_ino_timer; + dst->dqb_valid = QIF_ALL; +} + +static int quota_getquota(struct super_block *sb, int type, qid_t id, + void __user *addr) +{ + struct kqid qid; + struct qc_dqblk fdq; + struct if_dqblk idq; + int ret; + + if (!sb->s_qcop->get_dqblk) + return -ENOSYS; + qid = make_kqid(current_user_ns(), type, id); + if (!qid_valid(qid)) + return -EINVAL; + ret = sb->s_qcop->get_dqblk(sb, qid, &fdq); + if (ret) + return ret; + copy_to_if_dqblk(&idq, &fdq); + if (copy_to_user(addr, &idq, sizeof(idq))) + return -EFAULT; + return 0; +} + +static void copy_from_if_dqblk(struct qc_dqblk *dst, struct if_dqblk *src) +{ + dst->d_spc_hardlimit = qbtos(src->dqb_bhardlimit); + dst->d_spc_softlimit = qbtos(src->dqb_bsoftlimit); + dst->d_space = src->dqb_curspace; + dst->d_ino_hardlimit = src->dqb_ihardlimit; + dst->d_ino_softlimit = src->dqb_isoftlimit; + dst->d_ino_count = src->dqb_curinodes; + dst->d_spc_timer = src->dqb_btime; + dst->d_ino_timer = src->dqb_itime; + + dst->d_fieldmask = 0; + if (src->dqb_valid & QIF_BLIMITS) + dst->d_fieldmask |= QC_SPC_SOFT | QC_SPC_HARD; + if (src->dqb_valid & QIF_SPACE) + dst->d_fieldmask |= QC_SPACE; + if (src->dqb_valid & QIF_ILIMITS) + dst->d_fieldmask |= QC_INO_SOFT | QC_INO_HARD; + if (src->dqb_valid & QIF_INODES) + dst->d_fieldmask |= QC_INO_COUNT; + if (src->dqb_valid & QIF_BTIME) + dst->d_fieldmask |= QC_SPC_TIMER; + if (src->dqb_valid & QIF_ITIME) + dst->d_fieldmask |= QC_INO_TIMER; +} + +static int quota_setquota(struct super_block *sb, int type, qid_t id, + void __user *addr) +{ + struct qc_dqblk fdq; + struct if_dqblk idq; + struct kqid qid; + + if (copy_from_user(&idq, addr, sizeof(idq))) + return -EFAULT; + if (!sb->s_qcop->set_dqblk) + return -ENOSYS; + qid = make_kqid(current_user_ns(), type, id); + if (!qid_valid(qid)) + return -EINVAL; + copy_from_if_dqblk(&fdq, &idq); + return sb->s_qcop->set_dqblk(sb, qid, &fdq); +} + +static int quota_enable(struct super_block *sb, void __user *addr) +{ + __u32 flags; + + if (copy_from_user(&flags, addr, sizeof(flags))) + return -EFAULT; + if (!sb->s_qcop->quota_enable) + return -ENOSYS; + return sb->s_qcop->quota_enable(sb, flags); +} + +static int quota_disable(struct super_block *sb, void __user *addr) +{ + __u32 flags; + + if (copy_from_user(&flags, addr, sizeof(flags))) + return -EFAULT; + if (!sb->s_qcop->quota_disable) + return -ENOSYS; + return sb->s_qcop->quota_disable(sb, flags); +} + +static int quota_state_to_flags(struct qc_state *state) +{ + int flags = 0; + + if (state->s_state[USRQUOTA].flags & QCI_ACCT_ENABLED) + flags |= FS_QUOTA_UDQ_ACCT; + if (state->s_state[USRQUOTA].flags & QCI_LIMITS_ENFORCED) + flags |= FS_QUOTA_UDQ_ENFD; + if (state->s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED) + flags |= FS_QUOTA_GDQ_ACCT; + if (state->s_state[GRPQUOTA].flags & QCI_LIMITS_ENFORCED) + flags |= FS_QUOTA_GDQ_ENFD; + if (state->s_state[PRJQUOTA].flags & QCI_ACCT_ENABLED) + flags |= FS_QUOTA_PDQ_ACCT; + if (state->s_state[PRJQUOTA].flags & QCI_LIMITS_ENFORCED) + flags |= FS_QUOTA_PDQ_ENFD; + return flags; +} + +static int quota_getstate(struct super_block *sb, struct fs_quota_stat *fqs) +{ + int type; + struct qc_state state; + int ret; + + ret = sb->s_qcop->get_state(sb, &state); + if (ret < 0) + return ret; + + memset(fqs, 0, sizeof(*fqs)); + fqs->qs_version = FS_QSTAT_VERSION; + fqs->qs_flags = quota_state_to_flags(&state); + /* No quota enabled? */ + if (!fqs->qs_flags) + return -ENOSYS; + fqs->qs_incoredqs = state.s_incoredqs; + /* + * GETXSTATE quotactl has space for just one set of time limits so + * report them for the first enabled quota type + */ + for (type = 0; type < XQM_MAXQUOTAS; type++) + if (state.s_state[type].flags & QCI_ACCT_ENABLED) + break; + BUG_ON(type == XQM_MAXQUOTAS); + fqs->qs_btimelimit = state.s_state[type].spc_timelimit; + fqs->qs_itimelimit = state.s_state[type].ino_timelimit; + fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit; + fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit; + fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit; + if (state.s_state[USRQUOTA].flags & QCI_ACCT_ENABLED) { + fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino; + fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks; + fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents; + } + if (state.s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED) { + fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino; + fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks; + fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents; + } + if (state.s_state[PRJQUOTA].flags & QCI_ACCT_ENABLED) { + /* + * Q_XGETQSTAT doesn't have room for both group and project + * quotas. So, allow the project quota values to be copied out + * only if there is no group quota information available. + */ + if (!(state.s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED)) { + fqs->qs_gquota.qfs_ino = state.s_state[PRJQUOTA].ino; + fqs->qs_gquota.qfs_nblks = + state.s_state[PRJQUOTA].blocks; + fqs->qs_gquota.qfs_nextents = + state.s_state[PRJQUOTA].nextents; + } + } + return 0; +} + +static int quota_getxstate(struct super_block *sb, void __user *addr) +{ + struct fs_quota_stat fqs; + int ret; + + if (!sb->s_qcop->get_state) + return -ENOSYS; + ret = quota_getstate(sb, &fqs); + if (!ret && copy_to_user(addr, &fqs, sizeof(fqs))) + return -EFAULT; + return ret; +} + +static int quota_getstatev(struct super_block *sb, struct fs_quota_statv *fqs) +{ + int type; + struct qc_state state; + int ret; + + ret = sb->s_qcop->get_state(sb, &state); + if (ret < 0) + return ret; + + memset(fqs, 0, sizeof(*fqs)); + fqs->qs_version = FS_QSTAT_VERSION; + fqs->qs_flags = quota_state_to_flags(&state); + /* No quota enabled? */ + if (!fqs->qs_flags) + return -ENOSYS; + fqs->qs_incoredqs = state.s_incoredqs; + /* + * GETXSTATV quotactl has space for just one set of time limits so + * report them for the first enabled quota type + */ + for (type = 0; type < XQM_MAXQUOTAS; type++) + if (state.s_state[type].flags & QCI_ACCT_ENABLED) + break; + BUG_ON(type == XQM_MAXQUOTAS); + fqs->qs_btimelimit = state.s_state[type].spc_timelimit; + fqs->qs_itimelimit = state.s_state[type].ino_timelimit; + fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit; + fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit; + fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit; + if (state.s_state[USRQUOTA].flags & QCI_ACCT_ENABLED) { + fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino; + fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks; + fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents; + } + if (state.s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED) { + fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino; + fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks; + fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents; + } + if (state.s_state[PRJQUOTA].flags & QCI_ACCT_ENABLED) { + fqs->qs_pquota.qfs_ino = state.s_state[PRJQUOTA].ino; + fqs->qs_pquota.qfs_nblks = state.s_state[PRJQUOTA].blocks; + fqs->qs_pquota.qfs_nextents = state.s_state[PRJQUOTA].nextents; + } + return 0; +} + +static int quota_getxstatev(struct super_block *sb, void __user *addr) +{ + struct fs_quota_statv fqs; + int ret; + + if (!sb->s_qcop->get_state) + return -ENOSYS; + + memset(&fqs, 0, sizeof(fqs)); + if (copy_from_user(&fqs, addr, 1)) /* Just read qs_version */ + return -EFAULT; + + /* If this kernel doesn't support user specified version, fail */ + switch (fqs.qs_version) { + case FS_QSTATV_VERSION1: + break; + default: + return -EINVAL; + } + ret = quota_getstatev(sb, &fqs); + if (!ret && copy_to_user(addr, &fqs, sizeof(fqs))) + return -EFAULT; + return ret; +} + +/* + * XFS defines BBTOB and BTOBB macros inside fs/xfs/ and we cannot move them + * out of there as xfsprogs rely on definitions being in that header file. So + * just define same functions here for quota purposes. + */ +#define XFS_BB_SHIFT 9 + +static inline u64 quota_bbtob(u64 blocks) +{ + return blocks << XFS_BB_SHIFT; +} + +static inline u64 quota_btobb(u64 bytes) +{ + return (bytes + (1 << XFS_BB_SHIFT) - 1) >> XFS_BB_SHIFT; +} + +static void copy_from_xfs_dqblk(struct qc_dqblk *dst, struct fs_disk_quota *src) +{ + dst->d_spc_hardlimit = quota_bbtob(src->d_blk_hardlimit); + dst->d_spc_softlimit = quota_bbtob(src->d_blk_softlimit); + dst->d_ino_hardlimit = src->d_ino_hardlimit; + dst->d_ino_softlimit = src->d_ino_softlimit; + dst->d_space = quota_bbtob(src->d_bcount); + dst->d_ino_count = src->d_icount; + dst->d_ino_timer = src->d_itimer; + dst->d_spc_timer = src->d_btimer; + dst->d_ino_warns = src->d_iwarns; + dst->d_spc_warns = src->d_bwarns; + dst->d_rt_spc_hardlimit = quota_bbtob(src->d_rtb_hardlimit); + dst->d_rt_spc_softlimit = quota_bbtob(src->d_rtb_softlimit); + dst->d_rt_space = quota_bbtob(src->d_rtbcount); + dst->d_rt_spc_timer = src->d_rtbtimer; + dst->d_rt_spc_warns = src->d_rtbwarns; + dst->d_fieldmask = 0; + if (src->d_fieldmask & FS_DQ_ISOFT) + dst->d_fieldmask |= QC_INO_SOFT; + if (src->d_fieldmask & FS_DQ_IHARD) + dst->d_fieldmask |= QC_INO_HARD; + if (src->d_fieldmask & FS_DQ_BSOFT) + dst->d_fieldmask |= QC_SPC_SOFT; + if (src->d_fieldmask & FS_DQ_BHARD) + dst->d_fieldmask |= QC_SPC_HARD; + if (src->d_fieldmask & FS_DQ_RTBSOFT) + dst->d_fieldmask |= QC_RT_SPC_SOFT; + if (src->d_fieldmask & FS_DQ_RTBHARD) + dst->d_fieldmask |= QC_RT_SPC_HARD; + if (src->d_fieldmask & FS_DQ_BTIMER) + dst->d_fieldmask |= QC_SPC_TIMER; + if (src->d_fieldmask & FS_DQ_ITIMER) + dst->d_fieldmask |= QC_INO_TIMER; + if (src->d_fieldmask & FS_DQ_RTBTIMER) + dst->d_fieldmask |= QC_RT_SPC_TIMER; + if (src->d_fieldmask & FS_DQ_BWARNS) + dst->d_fieldmask |= QC_SPC_WARNS; + if (src->d_fieldmask & FS_DQ_IWARNS) + dst->d_fieldmask |= QC_INO_WARNS; + if (src->d_fieldmask & FS_DQ_RTBWARNS) + dst->d_fieldmask |= QC_RT_SPC_WARNS; + if (src->d_fieldmask & FS_DQ_BCOUNT) + dst->d_fieldmask |= QC_SPACE; + if (src->d_fieldmask & FS_DQ_ICOUNT) + dst->d_fieldmask |= QC_INO_COUNT; + if (src->d_fieldmask & FS_DQ_RTBCOUNT) + dst->d_fieldmask |= QC_RT_SPACE; +} + +static void copy_qcinfo_from_xfs_dqblk(struct qc_info *dst, + struct fs_disk_quota *src) +{ + memset(dst, 0, sizeof(*dst)); + dst->i_spc_timelimit = src->d_btimer; + dst->i_ino_timelimit = src->d_itimer; + dst->i_rt_spc_timelimit = src->d_rtbtimer; + dst->i_ino_warnlimit = src->d_iwarns; + dst->i_spc_warnlimit = src->d_bwarns; + dst->i_rt_spc_warnlimit = src->d_rtbwarns; + if (src->d_fieldmask & FS_DQ_BWARNS) + dst->i_fieldmask |= QC_SPC_WARNS; + if (src->d_fieldmask & FS_DQ_IWARNS) + dst->i_fieldmask |= QC_INO_WARNS; + if (src->d_fieldmask & FS_DQ_RTBWARNS) + dst->i_fieldmask |= QC_RT_SPC_WARNS; + if (src->d_fieldmask & FS_DQ_BTIMER) + dst->i_fieldmask |= QC_SPC_TIMER; + if (src->d_fieldmask & FS_DQ_ITIMER) + dst->i_fieldmask |= QC_INO_TIMER; + if (src->d_fieldmask & FS_DQ_RTBTIMER) + dst->i_fieldmask |= QC_RT_SPC_TIMER; +} + +static int quota_setxquota(struct super_block *sb, int type, qid_t id, + void __user *addr) +{ + struct fs_disk_quota fdq; + struct qc_dqblk qdq; + struct kqid qid; + + if (copy_from_user(&fdq, addr, sizeof(fdq))) + return -EFAULT; + if (!sb->s_qcop->set_dqblk) + return -ENOSYS; + qid = make_kqid(current_user_ns(), type, id); + if (!qid_valid(qid)) + return -EINVAL; + /* Are we actually setting timer / warning limits for all users? */ + if (from_kqid(&init_user_ns, qid) == 0 && + fdq.d_fieldmask & (FS_DQ_WARNS_MASK | FS_DQ_TIMER_MASK)) { + struct qc_info qinfo; + int ret; + + if (!sb->s_qcop->set_info) + return -EINVAL; + copy_qcinfo_from_xfs_dqblk(&qinfo, &fdq); + ret = sb->s_qcop->set_info(sb, type, &qinfo); + if (ret) + return ret; + /* These are already done */ + fdq.d_fieldmask &= ~(FS_DQ_WARNS_MASK | FS_DQ_TIMER_MASK); + } + copy_from_xfs_dqblk(&qdq, &fdq); + return sb->s_qcop->set_dqblk(sb, qid, &qdq); +} + +static void copy_to_xfs_dqblk(struct fs_disk_quota *dst, struct qc_dqblk *src, + int type, qid_t id) +{ + memset(dst, 0, sizeof(*dst)); + dst->d_version = FS_DQUOT_VERSION; + dst->d_id = id; + if (type == USRQUOTA) + dst->d_flags = FS_USER_QUOTA; + else if (type == PRJQUOTA) + dst->d_flags = FS_PROJ_QUOTA; + else + dst->d_flags = FS_GROUP_QUOTA; + dst->d_blk_hardlimit = quota_btobb(src->d_spc_hardlimit); + dst->d_blk_softlimit = quota_btobb(src->d_spc_softlimit); + dst->d_ino_hardlimit = src->d_ino_hardlimit; + dst->d_ino_softlimit = src->d_ino_softlimit; + dst->d_bcount = quota_btobb(src->d_space); + dst->d_icount = src->d_ino_count; + dst->d_itimer = src->d_ino_timer; + dst->d_btimer = src->d_spc_timer; + dst->d_iwarns = src->d_ino_warns; + dst->d_bwarns = src->d_spc_warns; + dst->d_rtb_hardlimit = quota_btobb(src->d_rt_spc_hardlimit); + dst->d_rtb_softlimit = quota_btobb(src->d_rt_spc_softlimit); + dst->d_rtbcount = quota_btobb(src->d_rt_space); + dst->d_rtbtimer = src->d_rt_spc_timer; + dst->d_rtbwarns = src->d_rt_spc_warns; +} + +static int quota_getxquota(struct super_block *sb, int type, qid_t id, + void __user *addr) +{ + struct fs_disk_quota fdq; + struct qc_dqblk qdq; + struct kqid qid; + int ret; + + if (!sb->s_qcop->get_dqblk) + return -ENOSYS; + qid = make_kqid(current_user_ns(), type, id); + if (!qid_valid(qid)) + return -EINVAL; + ret = sb->s_qcop->get_dqblk(sb, qid, &qdq); + if (ret) + return ret; + copy_to_xfs_dqblk(&fdq, &qdq, type, id); + if (copy_to_user(addr, &fdq, sizeof(fdq))) + return -EFAULT; + return ret; +} + +static int quota_rmxquota(struct super_block *sb, void __user *addr) +{ + __u32 flags; + + if (copy_from_user(&flags, addr, sizeof(flags))) + return -EFAULT; + if (!sb->s_qcop->rm_xquota) + return -ENOSYS; + return sb->s_qcop->rm_xquota(sb, flags); +} + +/* Copy parameters and call proper function */ +static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id, + void __user *addr, struct path *path) +{ + int ret; + + if (type >= (XQM_COMMAND(cmd) ? XQM_MAXQUOTAS : MAXQUOTAS)) + return -EINVAL; + /* + * Quota not supported on this fs? Check this before s_quota_types + * since they needn't be set if quota is not supported at all. + */ + if (!sb->s_qcop) + return -ENOSYS; + if (!(sb->s_quota_types & (1 << type))) + return -EINVAL; + + ret = check_quotactl_permission(sb, type, cmd, id); + if (ret < 0) + return ret; + + switch (cmd) { + case Q_QUOTAON: + return quota_quotaon(sb, type, cmd, id, path); + case Q_QUOTAOFF: + return quota_quotaoff(sb, type); + case Q_GETFMT: + return quota_getfmt(sb, type, addr); + case Q_GETINFO: + return quota_getinfo(sb, type, addr); + case Q_SETINFO: + return quota_setinfo(sb, type, addr); + case Q_GETQUOTA: + return quota_getquota(sb, type, id, addr); + case Q_SETQUOTA: + return quota_setquota(sb, type, id, addr); + case Q_SYNC: + if (!sb->s_qcop->quota_sync) + return -ENOSYS; + return sb->s_qcop->quota_sync(sb, type); + case Q_XQUOTAON: + return quota_enable(sb, addr); + case Q_XQUOTAOFF: + return quota_disable(sb, addr); + case Q_XQUOTARM: + return quota_rmxquota(sb, addr); + case Q_XGETQSTAT: + return quota_getxstate(sb, addr); + case Q_XGETQSTATV: + return quota_getxstatev(sb, addr); + case Q_XSETQLIM: + return quota_setxquota(sb, type, id, addr); + case Q_XGETQUOTA: + return quota_getxquota(sb, type, id, addr); + case Q_XQUOTASYNC: + if (sb->s_flags & MS_RDONLY) + return -EROFS; + /* XFS quotas are fully coherent now, making this call a noop */ + return 0; + default: + return -EINVAL; + } +} + +#ifdef CONFIG_BLOCK + +/* Return 1 if 'cmd' will block on frozen filesystem */ +static int quotactl_cmd_write(int cmd) +{ + switch (cmd) { + case Q_GETFMT: + case Q_GETINFO: + case Q_SYNC: + case Q_XGETQSTAT: + case Q_XGETQSTATV: + case Q_XGETQUOTA: + case Q_XQUOTASYNC: + return 0; + } + return 1; +} + +#endif /* CONFIG_BLOCK */ + +/* + * look up a superblock on which quota ops will be performed + * - use the name of a block device to find the superblock thereon + */ +static struct super_block *quotactl_block(const char __user *special, int cmd) +{ +#ifdef CONFIG_BLOCK + struct block_device *bdev; + struct super_block *sb; + struct filename *tmp = getname(special); + + if (IS_ERR(tmp)) + return ERR_CAST(tmp); + bdev = lookup_bdev(tmp->name); + putname(tmp); + if (IS_ERR(bdev)) + return ERR_CAST(bdev); + if (quotactl_cmd_write(cmd)) + sb = get_super_thawed(bdev); + else + sb = get_super(bdev); + bdput(bdev); + if (!sb) + return ERR_PTR(-ENODEV); + + return sb; +#else + return ERR_PTR(-ENODEV); +#endif +} + +/* + * This is the system call interface. This communicates with + * the user-level programs. Currently this only supports diskquota + * calls. Maybe we need to add the process quotas etc. in the future, + * but we probably should use rlimits for that. + */ +SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special, + qid_t, id, void __user *, addr) +{ + uint cmds, type; + struct super_block *sb = NULL; + struct path path, *pathp = NULL; + int ret; + + cmds = cmd >> SUBCMDSHIFT; + type = cmd & SUBCMDMASK; + + /* + * As a special case Q_SYNC can be called without a specific device. + * It will iterate all superblocks that have quota enabled and call + * the sync action on each of them. + */ + if (!special) { + if (cmds == Q_SYNC) + return quota_sync_all(type); + return -ENODEV; + } + + /* + * Path for quotaon has to be resolved before grabbing superblock + * because that gets s_umount sem which is also possibly needed by path + * resolution (think about autofs) and thus deadlocks could arise. + */ + if (cmds == Q_QUOTAON) { + ret = user_path_at(AT_FDCWD, addr, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &path); + if (ret) + pathp = ERR_PTR(ret); + else + pathp = &path; + } + + sb = quotactl_block(special, cmds); + if (IS_ERR(sb)) { + ret = PTR_ERR(sb); + goto out; + } + + ret = do_quotactl(sb, type, cmds, id, addr, pathp); + + drop_super(sb); +out: + if (pathp && !IS_ERR(pathp)) + path_put(pathp); + return ret; +} |