text: // SPDX-License-Identifier: GPL-2.0
  /*
   * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   * All Rights Reserved.
   */
  #include "xfs.h"
  #include "xfs_fs.h"
  #include "xfs_shared.h"
  #include "xfs_format.h"
  #include "xfs_log_format.h"
  #include "xfs_trans_resv.h"
  #include "xfs_quota.h"
  #include "xfs_mount.h"
  #include "xfs_inode.h"
  #include "xfs_trans.h"
  #include "xfs_qm.h"
  
  
  STATIC void
  xfs_fill_statvfs_from_dquot(
  	struct kstatfs		*statp,
  	struct xfs_dquot	*dqp)
  {
  	uint64_t		limit;
  
  	limit = dqp->q_blk.softlimit ?
  		dqp->q_blk.softlimit :
  		dqp->q_blk.hardlimit;
  	if (limit && statp->f_blocks > limit) {
  		statp->f_blocks = limit;
  		statp->f_bfree = statp->f_bavail =
  			(statp->f_blocks > dqp->q_blk.reserved) ?
  			 (statp->f_blocks - dqp->q_blk.reserved) : 0;
  	}
  
  	limit = dqp->q_ino.softlimit ?
  		dqp->q_ino.softlimit :
  		dqp->q_ino.hardlimit;
  	if (limit && statp->f_files > limit) {
  		statp->f_files = limit;
  		statp->f_ffree =
  			(statp->f_files > dqp->q_ino.reserved) ?
  			 (statp->f_files - dqp->q_ino.reserved) : 0;
  	}
  }
  
  
  /*
   * Directory tree accounting is implemented using project quotas, where
   * the project identifier is inherited from parent directories.
   * A statvfs (df, etc.) of a directory that is using project quota should
   * return a statvfs of the project, not the entire filesystem.
   * This makes such trees appear as if they are filesystems in themselves.
   */
  void
  xfs_qm_statvfs(
  	struct xfs_inode	*ip,
  	struct kstatfs		*statp)
  {
  	struct xfs_mount	*mp = ip->i_mount;
  	struct xfs_dquot	*dqp;
  
  	if (!xfs_qm_dqget(mp, ip->i_projid, XFS_DQTYPE_PROJ, false, &dqp)) {
  		xfs_fill_statvfs_from_dquot(statp, dqp);
  		xfs_qm_dqput(dqp);
  	}
  }
  
  int
  xfs_qm_newmount(
  	xfs_mount_t	*mp,
  	uint		*needquotamount,
  	uint		*quotaflags)
  {
  	uint		quotaondisk;
  	uint		uquotaondisk = 0, gquotaondisk = 0, pquotaondisk = 0;
  
  	quotaondisk = xfs_has_quota(mp) &&
  				(mp->m_sb.sb_qflags & XFS_ALL_QUOTA_ACCT);
  
  	if (quotaondisk) {
  		uquotaondisk = mp->m_sb.sb_qflags & XFS_UQUOTA_ACCT;
  		pquotaondisk = mp->m_sb.sb_qflags & XFS_PQUOTA_ACCT;
  		gquotaondisk = mp->m_sb.sb_qflags & XFS_GQUOTA_ACCT;
  	}
  
  	/*
  	 * If the device itself is read-only, we can't allow
  	 * the user to change the state of quota on the mount -
  	 * this would generate a transaction on the ro device,
  	 * which would lead to an I/O error and shutdown
  	 */
  
  	if (((uquotaondisk && !XFS_IS_UQUOTA_ON(mp)) ||
  	    (!uquotaondisk &&  XFS_IS_UQUOTA_ON(mp)) ||
  	     (gquotaondisk && !XFS_IS_GQUOTA_ON(mp)) ||
  	    (!gquotaondisk &&  XFS_IS_GQUOTA_ON(mp)) ||
  	     (pquotaondisk && !XFS_IS_PQUOTA_ON(mp)) ||
  	    (!pquotaondisk &&  XFS_IS_PQUOTA_ON(mp)))  &&
  	    xfs_dev_is_read_only(mp, "changing quota state")) {
  		xfs_warn(mp, "please mount with%s%s%s%s.",
  			(!quotaondisk ? "out quota" : ""),
  			(uquotaondisk ? " usrquota" : ""),
  			(gquotaondisk ? " grpquota" : ""),
  			(pquotaondisk ? " prjquota" : ""));
  		return -EPERM;
  	}
  
  	if (XFS_IS_QUOTA_ON(mp) || quotaondisk) {
  		/*
  		 * Call mount_quotas at this point only if we won't have to do
  		 * a quotacheck.
  		 */
  		if (quotaondisk && !XFS_QM_NEED_QUOTACHECK(mp)) {
  			/*
  			 * If an error occurred, qm_mount_quotas code
  			 * has already disabled quotas. So, just finish
  			 * mounting, and get on with the boring life
  			 * without disk quotas.
  			 */
  			xfs_qm_mount_quotas(mp);
  		} else {
  			/*
  			 * Clear the quota flags, but remember them. This
  			 * is so that the quota code doesn't get invoked
  			 * before we're ready. This can happen when an
  			 * inode goes inactive and wants to free blocks,
  			 * or via xfs_log_mount_finish.
  			 */
  			*needquotamount = true;
  			*quotaflags = mp->m_qflags;
  			mp->m_qflags = 0;
  		}
  	}
  
  	return 0;
  }
  