From f55abc0fb9c3189de3da829adf3220322c0da43e Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 20 Aug 2008 17:50:32 +0200 Subject: quota: Allow to separately enable quota accounting and enforcing limits Split DQUOT_USR_ENABLED (and DQUOT_GRP_ENABLED) into DQUOT_USR_USAGE_ENABLED and DQUOT_USR_LIMITS_ENABLED. This way we are able to separately enable / disable whether we should: 1) ignore quotas completely 2) just keep uptodate information about usage 3) actually enforce quota limits This is going to be useful when quota is treated as filesystem metadata - we then want to keep quota information uptodate all the time and just enable / disable limits enforcement. Signed-off-by: Jan Kara Signed-off-by: Mark Fasheh --- fs/dquot.c | 222 ++++++++++++++++++++++++++++++++++++++----------------------- 1 file changed, 138 insertions(+), 84 deletions(-) (limited to 'fs/dquot.c') diff --git a/fs/dquot.c b/fs/dquot.c index 22340c610e1a..7569633efe0e 100644 --- a/fs/dquot.c +++ b/fs/dquot.c @@ -489,7 +489,7 @@ int vfs_quota_sync(struct super_block *sb, int type) for (cnt = 0; cnt < MAXQUOTAS; cnt++) { if (type != -1 && cnt != type) continue; - if (!sb_has_quota_enabled(sb, cnt)) + if (!sb_has_quota_active(sb, cnt)) continue; spin_lock(&dq_list_lock); dirty = &dqopt->info[cnt].dqi_dirty_list; @@ -514,8 +514,8 @@ int vfs_quota_sync(struct super_block *sb, int type) } for (cnt = 0; cnt < MAXQUOTAS; cnt++) - if ((cnt == type || type == -1) && sb_has_quota_enabled(sb, cnt) - && info_dirty(&dqopt->info[cnt])) + if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt) + && info_dirty(&dqopt->info[cnt])) sb->dq_op->write_info(sb, cnt); spin_lock(&dq_list_lock); dqstats.syncs++; @@ -594,7 +594,7 @@ we_slept: /* We have more than one user... nothing to do */ atomic_dec(&dquot->dq_count); /* Releasing dquot during quotaoff phase? */ - if (!sb_has_quota_enabled(dquot->dq_sb, dquot->dq_type) && + if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_type) && atomic_read(&dquot->dq_count) == 1) wake_up(&dquot->dq_wait_unused); spin_unlock(&dq_list_lock); @@ -670,7 +670,7 @@ static struct dquot *dqget(struct super_block *sb, unsigned int id, int type) unsigned int hashent = hashfn(sb, id, type); struct dquot *dquot, *empty = NODQUOT; - if (!sb_has_quota_enabled(sb, type)) + if (!sb_has_quota_active(sb, type)) return NODQUOT; we_slept: spin_lock(&dq_list_lock); @@ -1041,7 +1041,8 @@ static inline char ignore_hardlimit(struct dquot *dquot) static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype) { *warntype = QUOTA_NL_NOWARN; - if (test_bit(DQ_FAKE_B, &dquot->dq_flags)) + if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) || + test_bit(DQ_FAKE_B, &dquot->dq_flags)) return QUOTA_OK; if (dquot->dq_dqb.dqb_ihardlimit && @@ -1073,7 +1074,8 @@ static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype) static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype) { *warntype = QUOTA_NL_NOWARN; - if (test_bit(DQ_FAKE_B, &dquot->dq_flags)) + if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) || + test_bit(DQ_FAKE_B, &dquot->dq_flags)) return QUOTA_OK; if (dquot->dq_dqb.dqb_bhardlimit && @@ -1114,7 +1116,8 @@ static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *war static int info_idq_free(struct dquot *dquot, qsize_t inodes) { if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || - dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) + dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || + !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type)) return QUOTA_NL_NOWARN; if (dquot->dq_dqb.dqb_curinodes - inodes <= dquot->dq_dqb.dqb_isoftlimit) @@ -1508,7 +1511,7 @@ warn_put_all: /* Wrapper for transferring ownership of an inode */ int vfs_dq_transfer(struct inode *inode, struct iattr *iattr) { - if (sb_any_quota_enabled(inode->i_sb) && !IS_NOQUOTA(inode)) { + if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode)) { vfs_dq_init(inode); if (inode->i_sb->dq_op->transfer(inode, iattr) == NO_QUOTA) return 1; @@ -1551,53 +1554,22 @@ struct dquot_operations dquot_operations = { .destroy_dquot = dquot_destroy, }; -static inline void set_enable_flags(struct quota_info *dqopt, int type) -{ - switch (type) { - case USRQUOTA: - dqopt->flags |= DQUOT_USR_ENABLED; - dqopt->flags &= ~DQUOT_USR_SUSPENDED; - break; - case GRPQUOTA: - dqopt->flags |= DQUOT_GRP_ENABLED; - dqopt->flags &= ~DQUOT_GRP_SUSPENDED; - break; - } -} - -static inline void reset_enable_flags(struct quota_info *dqopt, int type, - int remount) -{ - switch (type) { - case USRQUOTA: - if (remount) - dqopt->flags |= DQUOT_USR_SUSPENDED; - else { - dqopt->flags &= ~DQUOT_USR_ENABLED; - dqopt->flags &= ~DQUOT_USR_SUSPENDED; - } - break; - case GRPQUOTA: - if (remount) - dqopt->flags |= DQUOT_GRP_SUSPENDED; - else { - dqopt->flags &= ~DQUOT_GRP_ENABLED; - dqopt->flags &= ~DQUOT_GRP_SUSPENDED; - } - break; - } -} - - /* * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) */ -int vfs_quota_off(struct super_block *sb, int type, int remount) +int vfs_quota_disable(struct super_block *sb, int type, unsigned int flags) { int cnt, ret = 0; struct quota_info *dqopt = sb_dqopt(sb); struct inode *toputinode[MAXQUOTAS]; + /* Cannot turn off usage accounting without turning off limits, or + * suspend quotas and simultaneously turn quotas off. */ + if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) + || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | + DQUOT_USAGE_ENABLED))) + return -EINVAL; + /* We need to serialize quota_off() for device */ mutex_lock(&dqopt->dqonoff_mutex); @@ -1606,7 +1578,7 @@ int vfs_quota_off(struct super_block *sb, int type, int remount) * sometimes we are called when fill_super() failed and calling * sync_fs() in such cases does no good. */ - if (!sb_any_quota_enabled(sb) && !sb_any_quota_suspended(sb)) { + if (!sb_any_quota_loaded(sb)) { mutex_unlock(&dqopt->dqonoff_mutex); return 0; } @@ -1614,17 +1586,28 @@ int vfs_quota_off(struct super_block *sb, int type, int remount) toputinode[cnt] = NULL; if (type != -1 && cnt != type) continue; - /* If we keep inodes of quota files after remount and quotaoff - * is called, drop kept inodes. */ - if (!remount && sb_has_quota_suspended(sb, cnt)) { - iput(dqopt->files[cnt]); - dqopt->files[cnt] = NULL; - reset_enable_flags(dqopt, cnt, 0); + if (!sb_has_quota_loaded(sb, cnt)) continue; + + if (flags & DQUOT_SUSPENDED) { + dqopt->flags |= + dquot_state_flag(DQUOT_SUSPENDED, cnt); + } else { + dqopt->flags &= ~dquot_state_flag(flags, cnt); + /* Turning off suspended quotas? */ + if (!sb_has_quota_loaded(sb, cnt) && + sb_has_quota_suspended(sb, cnt)) { + dqopt->flags &= ~dquot_state_flag( + DQUOT_SUSPENDED, cnt); + iput(dqopt->files[cnt]); + dqopt->files[cnt] = NULL; + continue; + } } - if (!sb_has_quota_enabled(sb, cnt)) + + /* We still have to keep quota loaded? */ + if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) continue; - reset_enable_flags(dqopt, cnt, remount); /* Note: these are blocking operations */ drop_dquot_ref(sb, cnt); @@ -1640,7 +1623,7 @@ int vfs_quota_off(struct super_block *sb, int type, int remount) put_quota_format(dqopt->info[cnt].dqi_format); toputinode[cnt] = dqopt->files[cnt]; - if (!remount) + if (!sb_has_quota_loaded(sb, cnt)) dqopt->files[cnt] = NULL; dqopt->info[cnt].dqi_flags = 0; dqopt->info[cnt].dqi_igrace = 0; @@ -1663,7 +1646,7 @@ int vfs_quota_off(struct super_block *sb, int type, int remount) mutex_lock(&dqopt->dqonoff_mutex); /* If quota was reenabled in the meantime, we have * nothing to do */ - if (!sb_has_quota_enabled(sb, cnt)) { + if (!sb_has_quota_loaded(sb, cnt)) { mutex_lock_nested(&toputinode[cnt]->i_mutex, I_MUTEX_QUOTA); toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | S_NOATIME | S_NOQUOTA); @@ -1673,10 +1656,13 @@ int vfs_quota_off(struct super_block *sb, int type, int remount) } mutex_unlock(&dqopt->dqonoff_mutex); /* On remount RO, we keep the inode pointer so that we - * can reenable quota on the subsequent remount RW. - * But we have better not keep inode pointer when there - * is pending delete on the quota file... */ - if (!remount) + * can reenable quota on the subsequent remount RW. We + * have to check 'flags' variable and not use sb_has_ + * function because another quotaon / quotaoff could + * change global state before we got here. We refuse + * to suspend quotas when there is pending delete on + * the quota file... */ + if (!(flags & DQUOT_SUSPENDED)) iput(toputinode[cnt]); else if (!toputinode[cnt]->i_nlink) ret = -EBUSY; @@ -1686,12 +1672,22 @@ int vfs_quota_off(struct super_block *sb, int type, int remount) return ret; } +int vfs_quota_off(struct super_block *sb, int type, int remount) +{ + return vfs_quota_disable(sb, type, remount ? DQUOT_SUSPENDED : + (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED)); +} + /* * Turn quotas on on a device */ -/* Helper function when we already have the inode */ -static int vfs_quota_on_inode(struct inode *inode, int type, int format_id) +/* + * Helper function to turn quotas on when we already have the inode of + * quota file and no quota information is loaded. + */ +static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, + unsigned int flags) { struct quota_format_type *fmt = find_quota_format(format_id); struct super_block *sb = inode->i_sb; @@ -1713,6 +1709,11 @@ static int vfs_quota_on_inode(struct inode *inode, int type, int format_id) error = -EINVAL; goto out_fmt; } + /* Usage always has to be set... */ + if (!(flags & DQUOT_USAGE_ENABLED)) { + error = -EINVAL; + goto out_fmt; + } /* As we bypass the pagecache we must now flush the inode so that * we see all the changes from userspace... */ @@ -1721,8 +1722,7 @@ static int vfs_quota_on_inode(struct inode *inode, int type, int format_id) invalidate_bdev(sb->s_bdev); mutex_lock(&inode->i_mutex); mutex_lock(&dqopt->dqonoff_mutex); - if (sb_has_quota_enabled(sb, type) || - sb_has_quota_suspended(sb, type)) { + if (sb_has_quota_loaded(sb, type)) { error = -EBUSY; goto out_lock; } @@ -1754,7 +1754,7 @@ static int vfs_quota_on_inode(struct inode *inode, int type, int format_id) } mutex_unlock(&dqopt->dqio_mutex); mutex_unlock(&inode->i_mutex); - set_enable_flags(dqopt, type); + dqopt->flags |= dquot_state_flag(flags, type); add_dquot_ref(sb, type); mutex_unlock(&dqopt->dqonoff_mutex); @@ -1787,20 +1787,23 @@ static int vfs_quota_on_remount(struct super_block *sb, int type) struct quota_info *dqopt = sb_dqopt(sb); struct inode *inode; int ret; + unsigned int flags; mutex_lock(&dqopt->dqonoff_mutex); if (!sb_has_quota_suspended(sb, type)) { mutex_unlock(&dqopt->dqonoff_mutex); return 0; } - BUG_ON(sb_has_quota_enabled(sb, type)); - inode = dqopt->files[type]; dqopt->files[type] = NULL; - reset_enable_flags(dqopt, type, 0); + flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | + DQUOT_LIMITS_ENABLED, type); + dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, type); mutex_unlock(&dqopt->dqonoff_mutex); - ret = vfs_quota_on_inode(inode, type, dqopt->info[type].dqi_fmt_id); + flags = dquot_generic_flag(flags, type); + ret = vfs_load_quota_inode(inode, type, dqopt->info[type].dqi_fmt_id, + flags); iput(inode); return ret; @@ -1816,12 +1819,12 @@ int vfs_quota_on_path(struct super_block *sb, int type, int format_id, if (path->mnt->mnt_sb != sb) error = -EXDEV; else - error = vfs_quota_on_inode(path->dentry->d_inode, type, - format_id); + error = vfs_load_quota_inode(path->dentry->d_inode, type, + format_id, DQUOT_USAGE_ENABLED | + DQUOT_LIMITS_ENABLED); return error; } -/* Actual function called from quotactl() */ int vfs_quota_on(struct super_block *sb, int type, int format_id, char *name, int remount) { @@ -1839,6 +1842,50 @@ int vfs_quota_on(struct super_block *sb, int type, int format_id, char *name, return error; } +/* + * More powerful function for turning on quotas allowing setting + * of individual quota flags + */ +int vfs_quota_enable(struct inode *inode, int type, int format_id, + unsigned int flags) +{ + int ret = 0; + struct super_block *sb = inode->i_sb; + struct quota_info *dqopt = sb_dqopt(sb); + + /* Just unsuspend quotas? */ + if (flags & DQUOT_SUSPENDED) + return vfs_quota_on_remount(sb, type); + if (!flags) + return 0; + /* Just updating flags needed? */ + if (sb_has_quota_loaded(sb, type)) { + mutex_lock(&dqopt->dqonoff_mutex); + /* Now do a reliable test... */ + if (!sb_has_quota_loaded(sb, type)) { + mutex_unlock(&dqopt->dqonoff_mutex); + goto load_quota; + } + if (flags & DQUOT_USAGE_ENABLED && + sb_has_quota_usage_enabled(sb, type)) { + ret = -EBUSY; + goto out_lock; + } + if (flags & DQUOT_LIMITS_ENABLED && + sb_has_quota_limits_enabled(sb, type)) { + ret = -EBUSY; + goto out_lock; + } + sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); +out_lock: + mutex_unlock(&dqopt->dqonoff_mutex); + return ret; + } + +load_quota: + return vfs_load_quota_inode(inode, type, format_id, flags); +} + /* * This function is used when filesystem needs to initialize quotas * during mount time. @@ -1860,7 +1907,8 @@ int vfs_quota_on_mount(struct super_block *sb, char *qf_name, error = security_quota_on(dentry); if (!error) - error = vfs_quota_on_inode(dentry->d_inode, type, format_id); + error = vfs_load_quota_inode(dentry->d_inode, type, format_id, + DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); out: dput(dentry); @@ -1997,12 +2045,14 @@ int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *d int rc; mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); - if (!(dquot = dqget(sb, id, type))) { - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); - return -ESRCH; + dquot = dqget(sb, id, type); + if (!dquot) { + rc = -ESRCH; + goto out; } rc = do_set_dqblk(dquot, di); dqput(dquot); +out: mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); return rc; } @@ -2013,7 +2063,7 @@ int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) struct mem_dqinfo *mi; mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); - if (!sb_has_quota_enabled(sb, type)) { + if (!sb_has_quota_active(sb, type)) { mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); return -ESRCH; } @@ -2032,11 +2082,12 @@ int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) { struct mem_dqinfo *mi; + int err = 0; mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); - if (!sb_has_quota_enabled(sb, type)) { - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); - return -ESRCH; + if (!sb_has_quota_active(sb, type)) { + err = -ESRCH; + goto out; } mi = sb_dqopt(sb)->info + type; spin_lock(&dq_data_lock); @@ -2050,8 +2101,9 @@ int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) mark_info_dirty(sb, type); /* Force write to disk */ sb->dq_op->write_info(sb, type); +out: mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); - return 0; + return err; } struct quotactl_ops vfs_quotactl_ops = { @@ -2213,9 +2265,11 @@ EXPORT_SYMBOL(register_quota_format); EXPORT_SYMBOL(unregister_quota_format); EXPORT_SYMBOL(dqstats); EXPORT_SYMBOL(dq_data_lock); +EXPORT_SYMBOL(vfs_quota_enable); EXPORT_SYMBOL(vfs_quota_on); EXPORT_SYMBOL(vfs_quota_on_path); EXPORT_SYMBOL(vfs_quota_on_mount); +EXPORT_SYMBOL(vfs_quota_disable); EXPORT_SYMBOL(vfs_quota_off); EXPORT_SYMBOL(vfs_quota_sync); EXPORT_SYMBOL(vfs_get_dqinfo); -- cgit v1.2.3