// SPDX-License-Identifier: GPL-2.0

  /*
   * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   * Copyright (c) 2013 Red Hat, 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_bit.h"

  #include "xfs_mount.h"

  #include "xfs_da_format.h"

  #include "xfs_da_btree.h"

  #include "xfs_inode.h"

  #include "xfs_alloc.h"

  #include "xfs_attr_remote.h"

  #include "xfs_trans.h"

  #include "xfs_inode_item.h"
  #include "xfs_bmap.h"
  #include "xfs_attr.h"
  #include "xfs_attr_leaf.h"
  #include "xfs_error.h"
  #include "xfs_quota.h"
  #include "xfs_trace.h"

  #include "xfs_dir2.h"

  #include "xfs_defer.h"

  
  /*
   * Look at all the extents for this logical region,
   * invalidate any buffers that are incore/in transactions.
   */
  STATIC int
  xfs_attr3_leaf_freextent(
  	struct xfs_trans	**trans,
  	struct xfs_inode	*dp,
  	xfs_dablk_t		blkno,
  	int			blkcnt)
  {
  	struct xfs_bmbt_irec	map;
  	struct xfs_buf		*bp;
  	xfs_dablk_t		tblkno;
  	xfs_daddr_t		dblkno;
  	int			tblkcnt;
  	int			dblkcnt;
  	int			nmap;
  	int			error;
  
  	/*
  	 * Roll through the "value", invalidating the attribute value's
  	 * blocks.
  	 */
  	tblkno = blkno;
  	tblkcnt = blkcnt;
  	while (tblkcnt > 0) {
  		/*
  		 * Try to remember where we decided to put the value.
  		 */
  		nmap = 1;
  		error = xfs_bmapi_read(dp, (xfs_fileoff_t)tblkno, tblkcnt,
  				       &map, &nmap, XFS_BMAPI_ATTRFORK);
  		if (error) {

  			return error;

  		}
  		ASSERT(nmap == 1);
  		ASSERT(map.br_startblock != DELAYSTARTBLOCK);
  
  		/*
  		 * If it's a hole, these are already unmapped
  		 * so there's nothing to invalidate.
  		 */
  		if (map.br_startblock != HOLESTARTBLOCK) {
  
  			dblkno = XFS_FSB_TO_DADDR(dp->i_mount,
  						  map.br_startblock);
  			dblkcnt = XFS_FSB_TO_BB(dp->i_mount,
  						map.br_blockcount);
  			bp = xfs_trans_get_buf(*trans,
  					dp->i_mount->m_ddev_targp,
  					dblkno, dblkcnt, 0);
  			if (!bp)

  				return -ENOMEM;

  			xfs_trans_binval(*trans, bp);
  			/*
  			 * Roll to next transaction.
  			 */

  			error = xfs_trans_roll_inode(trans, dp);

  			if (error)

  				return error;

  		}
  
  		tblkno += map.br_blockcount;
  		tblkcnt -= map.br_blockcount;
  	}

  	return 0;

  }
  
  /*
   * Invalidate all of the "remote" value regions pointed to by a particular
   * leaf block.
   * Note that we must release the lock on the buffer so that we are not
   * caught holding something that the logging code wants to flush to disk.
   */
  STATIC int
  xfs_attr3_leaf_inactive(
  	struct xfs_trans	**trans,
  	struct xfs_inode	*dp,
  	struct xfs_buf		*bp)
  {
  	struct xfs_attr_leafblock *leaf;
  	struct xfs_attr3_icleaf_hdr ichdr;
  	struct xfs_attr_leaf_entry *entry;
  	struct xfs_attr_leaf_name_remote *name_rmt;
  	struct xfs_attr_inactive_list *list;
  	struct xfs_attr_inactive_list *lp;
  	int			error;
  	int			count;
  	int			size;
  	int			tmp;
  	int			i;

  	struct xfs_mount	*mp = bp->b_target->bt_mount;

  
  	leaf = bp->b_addr;

  	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);

  
  	/*
  	 * Count the number of "remote" value extents.
  	 */
  	count = 0;
  	entry = xfs_attr3_leaf_entryp(leaf);
  	for (i = 0; i < ichdr.count; entry++, i++) {
  		if (be16_to_cpu(entry->nameidx) &&
  		    ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
  			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
  			if (name_rmt->valueblk)
  				count++;
  		}
  	}
  
  	/*
  	 * If there are no "remote" values, we're done.
  	 */
  	if (count == 0) {
  		xfs_trans_brelse(*trans, bp);
  		return 0;
  	}
  
  	/*
  	 * Allocate storage for a list of all the "remote" value extents.
  	 */
  	size = count * sizeof(xfs_attr_inactive_list_t);
  	list = kmem_alloc(size, KM_SLEEP);
  
  	/*
  	 * Identify each of the "remote" value extents.
  	 */
  	lp = list;
  	entry = xfs_attr3_leaf_entryp(leaf);
  	for (i = 0; i < ichdr.count; entry++, i++) {
  		if (be16_to_cpu(entry->nameidx) &&
  		    ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
  			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
  			if (name_rmt->valueblk) {
  				lp->valueblk = be32_to_cpu(name_rmt->valueblk);
  				lp->valuelen = xfs_attr3_rmt_blocks(dp->i_mount,
  						    be32_to_cpu(name_rmt->valuelen));
  				lp++;
  			}
  		}
  	}
  	xfs_trans_brelse(*trans, bp);	/* unlock for trans. in freextent() */
  
  	/*
  	 * Invalidate each of the "remote" value extents.
  	 */
  	error = 0;
  	for (lp = list, i = 0; i < count; i++, lp++) {
  		tmp = xfs_attr3_leaf_freextent(trans, dp,
  				lp->valueblk, lp->valuelen);
  
  		if (error == 0)
  			error = tmp;	/* save only the 1st errno */
  	}
  
  	kmem_free(list);
  	return error;
  }
  
  /*
   * Recurse (gasp!) through the attribute nodes until we find leaves.
   * We're doing a depth-first traversal in order to invalidate everything.
   */
  STATIC int
  xfs_attr3_node_inactive(
  	struct xfs_trans **trans,
  	struct xfs_inode *dp,
  	struct xfs_buf	*bp,
  	int		level)
  {
  	xfs_da_blkinfo_t *info;
  	xfs_da_intnode_t *node;
  	xfs_dablk_t child_fsb;
  	xfs_daddr_t parent_blkno, child_blkno;
  	int error, i;
  	struct xfs_buf *child_bp;
  	struct xfs_da_node_entry *btree;
  	struct xfs_da3_icnode_hdr ichdr;
  
  	/*
  	 * Since this code is recursive (gasp!) we must protect ourselves.
  	 */
  	if (level > XFS_DA_NODE_MAXDEPTH) {
  		xfs_trans_brelse(*trans, bp);	/* no locks for later trans */

  		return -EIO;

  	}
  
  	node = bp->b_addr;

  	dp->d_ops->node_hdr_from_disk(&ichdr, node);

  	parent_blkno = bp->b_bn;
  	if (!ichdr.count) {
  		xfs_trans_brelse(*trans, bp);
  		return 0;
  	}

  	btree = dp->d_ops->node_tree_p(node);

  	child_fsb = be32_to_cpu(btree[0].before);
  	xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
  
  	/*
  	 * If this is the node level just above the leaves, simply loop
  	 * over the leaves removing all of them.  If this is higher up
  	 * in the tree, recurse downward.
  	 */
  	for (i = 0; i < ichdr.count; i++) {
  		/*
  		 * Read the subsidiary block to see what we have to work with.
  		 * Don't do this in a transaction.  This is a depth-first
  		 * traversal of the tree so we may deal with many blocks
  		 * before we come back to this one.
  		 */

  		error = xfs_da3_node_read(*trans, dp, child_fsb, -1, &child_bp,
  					  XFS_ATTR_FORK);

  		if (error)

  			return error;

  		/* save for re-read later */
  		child_blkno = XFS_BUF_ADDR(child_bp);

  		/*
  		 * Invalidate the subtree, however we have to.
  		 */
  		info = child_bp->b_addr;
  		switch (info->magic) {
  		case cpu_to_be16(XFS_DA_NODE_MAGIC):
  		case cpu_to_be16(XFS_DA3_NODE_MAGIC):
  			error = xfs_attr3_node_inactive(trans, dp, child_bp,
  							level + 1);
  			break;
  		case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
  		case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
  			error = xfs_attr3_leaf_inactive(trans, dp, child_bp);
  			break;
  		default:
  			error = -EIO;
  			xfs_trans_brelse(*trans, child_bp);
  			break;

  		}

  		if (error)
  			return error;
  
  		/*
  		 * Remove the subsidiary block from the cache and from the log.
  		 */
  		error = xfs_da_get_buf(*trans, dp, 0, child_blkno, &child_bp,
  				       XFS_ATTR_FORK);
  		if (error)
  			return error;
  		xfs_trans_binval(*trans, child_bp);

  
  		/*
  		 * If we're not done, re-read the parent to get the next
  		 * child block number.
  		 */
  		if (i + 1 < ichdr.count) {
  			error = xfs_da3_node_read(*trans, dp, 0, parent_blkno,
  						 &bp, XFS_ATTR_FORK);
  			if (error)
  				return error;

  			node = bp->b_addr;
  			btree = dp->d_ops->node_tree_p(node);

  			child_fsb = be32_to_cpu(btree[i + 1].before);
  			xfs_trans_brelse(*trans, bp);
  		}
  		/*
  		 * Atomically commit the whole invalidate stuff.
  		 */

  		error = xfs_trans_roll_inode(trans, dp);

  		if (error)
  			return  error;
  	}
  
  	return 0;
  }
  
  /*
   * Indiscriminately delete the entire attribute fork
   *
   * Recurse (gasp!) through the attribute nodes until we find leaves.
   * We're doing a depth-first traversal in order to invalidate everything.
   */

  static int

  xfs_attr3_root_inactive(
  	struct xfs_trans	**trans,
  	struct xfs_inode	*dp)
  {
  	struct xfs_da_blkinfo	*info;
  	struct xfs_buf		*bp;
  	xfs_daddr_t		blkno;
  	int			error;
  
  	/*
  	 * Read block 0 to see what we have to work with.
  	 * We only get here if we have extents, since we remove
  	 * the extents in reverse order the extent containing
  	 * block 0 must still be there.
  	 */
  	error = xfs_da3_node_read(*trans, dp, 0, -1, &bp, XFS_ATTR_FORK);
  	if (error)
  		return error;
  	blkno = bp->b_bn;
  
  	/*
  	 * Invalidate the tree, even if the "tree" is only a single leaf block.
  	 * This is a depth-first traversal!
  	 */
  	info = bp->b_addr;
  	switch (info->magic) {
  	case cpu_to_be16(XFS_DA_NODE_MAGIC):
  	case cpu_to_be16(XFS_DA3_NODE_MAGIC):
  		error = xfs_attr3_node_inactive(trans, dp, bp, 1);
  		break;
  	case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
  	case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
  		error = xfs_attr3_leaf_inactive(trans, dp, bp);
  		break;
  	default:

  		error = -EIO;

  		xfs_trans_brelse(*trans, bp);
  		break;
  	}
  	if (error)
  		return error;
  
  	/*
  	 * Invalidate the incore copy of the root block.
  	 */
  	error = xfs_da_get_buf(*trans, dp, 0, blkno, &bp, XFS_ATTR_FORK);
  	if (error)
  		return error;
  	xfs_trans_binval(*trans, bp);	/* remove from cache */
  	/*
  	 * Commit the invalidate and start the next transaction.
  	 */

  	error = xfs_trans_roll_inode(trans, dp);

  
  	return error;
  }

  /*
   * xfs_attr_inactive kills all traces of an attribute fork on an inode. It
   * removes both the on-disk and in-memory inode fork. Note that this also has to
   * handle the condition of inodes without attributes but with an attribute fork
   * configured, so we can't use xfs_inode_hasattr() here.
   *
   * The in-memory attribute fork is removed even on error.
   */

  int

  xfs_attr_inactive(
  	struct xfs_inode	*dp)

  {

  	struct xfs_trans	*trans;
  	struct xfs_mount	*mp;

  	int			lock_mode = XFS_ILOCK_SHARED;
  	int			error = 0;

  
  	mp = dp->i_mount;
  	ASSERT(! XFS_NOT_DQATTACHED(mp, dp));

  	xfs_ilock(dp, lock_mode);
  	if (!XFS_IFORK_Q(dp))
  		goto out_destroy_fork;
  	xfs_iunlock(dp, lock_mode);

  	lock_mode = 0;

  
  	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrinval, 0, 0, 0, &trans);

  	if (error)

  		goto out_destroy_fork;

  
  	lock_mode = XFS_ILOCK_EXCL;

  	xfs_ilock(dp, lock_mode);
  
  	if (!XFS_IFORK_Q(dp))
  		goto out_cancel;

  
  	/*
  	 * No need to make quota reservations here. We expect to release some
  	 * blocks, not allocate, in the common case.
  	 */
  	xfs_trans_ijoin(trans, dp, 0);

  	/*
  	 * Invalidate and truncate the attribute fork extents. Make sure the
  	 * fork actually has attributes as otherwise the invalidation has no
  	 * blocks to read and returns an error. In this case, just do the fork
  	 * removal below.
  	 */
  	if (xfs_inode_hasattr(dp) &&
  	    dp->i_d.di_aformat != XFS_DINODE_FMT_LOCAL) {

  		error = xfs_attr3_root_inactive(&trans, dp);
  		if (error)
  			goto out_cancel;
  
  		error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
  		if (error)
  			goto out_cancel;

  	}

  	/* Reset the attribute fork - this also destroys the in-core fork */
  	xfs_attr_fork_remove(dp, trans);

  	error = xfs_trans_commit(trans);

  	xfs_iunlock(dp, lock_mode);

  	return error;

  out_cancel:

  	xfs_trans_cancel(trans);

  out_destroy_fork:
  	/* kill the in-core attr fork before we drop the inode lock */
  	if (dp->i_afp)
  		xfs_idestroy_fork(dp, XFS_ATTR_FORK);
  	if (lock_mode)
  		xfs_iunlock(dp, lock_mode);

  	return error;

  }