/*
   * linux/fs/ocfs2/ioctl.c
   *
   * Copyright (C) 2006 Herbert Poetzl
   * adapted from Remy Card's ext2/ioctl.c
   */
  
  #include <linux/fs.h>
  #include <linux/mount.h>

  #include <linux/compat.h>

  #include <cluster/masklog.h>
  
  #include "ocfs2.h"
  #include "alloc.h"
  #include "dlmglue.h"

  #include "file.h"

  #include "inode.h"
  #include "journal.h"
  
  #include "ocfs2_fs.h"

  #include "ioctl.h"

  #include "resize.h"

  #include "refcounttree.h"

  #include "sysfile.h"
  #include "dir.h"
  #include "buffer_head_io.h"

  #include "suballoc.h"

  #include "move_extents.h"

  #include <linux/ext2_fs.h>

  #define o2info_from_user(a, b)	\
  		copy_from_user(&(a), (b), sizeof(a))
  #define o2info_to_user(a, b)	\
  		copy_to_user((typeof(a) __user *)b, &(a), sizeof(a))
  
  /*
   * This call is void because we are already reporting an error that may
   * be -EFAULT.  The error will be returned from the ioctl(2) call.  It's
   * just a best-effort to tell userspace that this request caused the error.
   */

  static inline void o2info_set_request_error(struct ocfs2_info_request *kreq,

  					struct ocfs2_info_request __user *req)
  {
  	kreq->ir_flags |= OCFS2_INFO_FL_ERROR;
  	(void)put_user(kreq->ir_flags, (__u32 __user *)&(req->ir_flags));
  }

  static inline void o2info_set_request_filled(struct ocfs2_info_request *req)

  {
  	req->ir_flags |= OCFS2_INFO_FL_FILLED;
  }

  static inline void o2info_clear_request_filled(struct ocfs2_info_request *req)

  {
  	req->ir_flags &= ~OCFS2_INFO_FL_FILLED;
  }

  static inline int o2info_coherent(struct ocfs2_info_request *req)
  {
  	return (!(req->ir_flags & OCFS2_INFO_FL_NON_COHERENT));
  }

  static int ocfs2_get_inode_attr(struct inode *inode, unsigned *flags)
  {
  	int status;

  	status = ocfs2_inode_lock(inode, NULL, 0);

  	if (status < 0) {
  		mlog_errno(status);
  		return status;
  	}

  	ocfs2_get_inode_flags(OCFS2_I(inode));

  	*flags = OCFS2_I(inode)->ip_attr;

  	ocfs2_inode_unlock(inode, 0);

  	return status;
  }
  
  static int ocfs2_set_inode_attr(struct inode *inode, unsigned flags,
  				unsigned mask)
  {
  	struct ocfs2_inode_info *ocfs2_inode = OCFS2_I(inode);
  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);

  	handle_t *handle = NULL;

  	struct buffer_head *bh = NULL;
  	unsigned oldflags;
  	int status;
  
  	mutex_lock(&inode->i_mutex);

  	status = ocfs2_inode_lock(inode, &bh, 1);

  	if (status < 0) {
  		mlog_errno(status);
  		goto bail;
  	}

  	status = -EACCES;

  	if (!inode_owner_or_capable(inode))

  		goto bail_unlock;
  
  	if (!S_ISDIR(inode->i_mode))
  		flags &= ~OCFS2_DIRSYNC_FL;

  	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);

  	if (IS_ERR(handle)) {
  		status = PTR_ERR(handle);
  		mlog_errno(status);
  		goto bail_unlock;
  	}
  
  	oldflags = ocfs2_inode->ip_attr;
  	flags = flags & mask;
  	flags |= oldflags & ~mask;
  
  	/*
  	 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
  	 * the relevant capability.
  	 */
  	status = -EPERM;
  	if ((oldflags & OCFS2_IMMUTABLE_FL) || ((flags ^ oldflags) &
  		(OCFS2_APPEND_FL | OCFS2_IMMUTABLE_FL))) {
  		if (!capable(CAP_LINUX_IMMUTABLE))

  			goto bail_commit;

  	}
  
  	ocfs2_inode->ip_attr = flags;
  	ocfs2_set_inode_flags(inode);
  
  	status = ocfs2_mark_inode_dirty(handle, inode, bh);
  	if (status < 0)
  		mlog_errno(status);

  bail_commit:

  	ocfs2_commit_trans(osb, handle);

  bail_unlock:

  	ocfs2_inode_unlock(inode, 1);

  bail:
  	mutex_unlock(&inode->i_mutex);

  	brelse(bh);

  	return status;
  }

  int ocfs2_info_handle_blocksize(struct inode *inode,
  				struct ocfs2_info_request __user *req)
  {
  	int status = -EFAULT;
  	struct ocfs2_info_blocksize oib;
  
  	if (o2info_from_user(oib, req))
  		goto bail;
  
  	oib.ib_blocksize = inode->i_sb->s_blocksize;

  	o2info_set_request_filled(&oib.ib_req);

  
  	if (o2info_to_user(oib, req))
  		goto bail;
  
  	status = 0;
  bail:
  	if (status)

  		o2info_set_request_error(&oib.ib_req, req);

  
  	return status;
  }
  
  int ocfs2_info_handle_clustersize(struct inode *inode,
  				  struct ocfs2_info_request __user *req)
  {
  	int status = -EFAULT;
  	struct ocfs2_info_clustersize oic;
  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  
  	if (o2info_from_user(oic, req))
  		goto bail;
  
  	oic.ic_clustersize = osb->s_clustersize;

  	o2info_set_request_filled(&oic.ic_req);

  
  	if (o2info_to_user(oic, req))
  		goto bail;
  
  	status = 0;
  bail:
  	if (status)

  		o2info_set_request_error(&oic.ic_req, req);

  
  	return status;
  }
  
  int ocfs2_info_handle_maxslots(struct inode *inode,
  			       struct ocfs2_info_request __user *req)
  {
  	int status = -EFAULT;
  	struct ocfs2_info_maxslots oim;
  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  
  	if (o2info_from_user(oim, req))
  		goto bail;
  
  	oim.im_max_slots = osb->max_slots;

  	o2info_set_request_filled(&oim.im_req);

  
  	if (o2info_to_user(oim, req))
  		goto bail;
  
  	status = 0;
  bail:
  	if (status)

  		o2info_set_request_error(&oim.im_req, req);

  
  	return status;
  }
  
  int ocfs2_info_handle_label(struct inode *inode,
  			    struct ocfs2_info_request __user *req)
  {
  	int status = -EFAULT;
  	struct ocfs2_info_label oil;
  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  
  	if (o2info_from_user(oil, req))
  		goto bail;
  
  	memcpy(oil.il_label, osb->vol_label, OCFS2_MAX_VOL_LABEL_LEN);

  	o2info_set_request_filled(&oil.il_req);

  
  	if (o2info_to_user(oil, req))
  		goto bail;
  
  	status = 0;
  bail:
  	if (status)

  		o2info_set_request_error(&oil.il_req, req);

  
  	return status;
  }
  
  int ocfs2_info_handle_uuid(struct inode *inode,
  			   struct ocfs2_info_request __user *req)
  {
  	int status = -EFAULT;
  	struct ocfs2_info_uuid oiu;
  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  
  	if (o2info_from_user(oiu, req))
  		goto bail;
  
  	memcpy(oiu.iu_uuid_str, osb->uuid_str, OCFS2_TEXT_UUID_LEN + 1);

  	o2info_set_request_filled(&oiu.iu_req);

  
  	if (o2info_to_user(oiu, req))
  		goto bail;
  
  	status = 0;
  bail:
  	if (status)

  		o2info_set_request_error(&oiu.iu_req, req);

  
  	return status;
  }
  
  int ocfs2_info_handle_fs_features(struct inode *inode,
  				  struct ocfs2_info_request __user *req)
  {
  	int status = -EFAULT;
  	struct ocfs2_info_fs_features oif;
  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  
  	if (o2info_from_user(oif, req))
  		goto bail;
  
  	oif.if_compat_features = osb->s_feature_compat;
  	oif.if_incompat_features = osb->s_feature_incompat;
  	oif.if_ro_compat_features = osb->s_feature_ro_compat;

  	o2info_set_request_filled(&oif.if_req);

  
  	if (o2info_to_user(oif, req))
  		goto bail;
  
  	status = 0;
  bail:
  	if (status)

  		o2info_set_request_error(&oif.if_req, req);

  
  	return status;
  }
  
  int ocfs2_info_handle_journal_size(struct inode *inode,
  				   struct ocfs2_info_request __user *req)
  {
  	int status = -EFAULT;
  	struct ocfs2_info_journal_size oij;
  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  
  	if (o2info_from_user(oij, req))
  		goto bail;
  
  	oij.ij_journal_size = osb->journal->j_inode->i_size;

  	o2info_set_request_filled(&oij.ij_req);

  
  	if (o2info_to_user(oij, req))
  		goto bail;
  
  	status = 0;
  bail:
  	if (status)

  		o2info_set_request_error(&oij.ij_req, req);

  
  	return status;
  }

  int ocfs2_info_scan_inode_alloc(struct ocfs2_super *osb,
  				struct inode *inode_alloc, u64 blkno,
  				struct ocfs2_info_freeinode *fi, u32 slot)
  {
  	int status = 0, unlock = 0;
  
  	struct buffer_head *bh = NULL;
  	struct ocfs2_dinode *dinode_alloc = NULL;
  
  	if (inode_alloc)
  		mutex_lock(&inode_alloc->i_mutex);
  
  	if (o2info_coherent(&fi->ifi_req)) {
  		status = ocfs2_inode_lock(inode_alloc, &bh, 0);
  		if (status < 0) {
  			mlog_errno(status);
  			goto bail;
  		}
  		unlock = 1;
  	} else {
  		status = ocfs2_read_blocks_sync(osb, blkno, 1, &bh);
  		if (status < 0) {
  			mlog_errno(status);
  			goto bail;
  		}
  	}
  
  	dinode_alloc = (struct ocfs2_dinode *)bh->b_data;
  
  	fi->ifi_stat[slot].lfi_total =
  		le32_to_cpu(dinode_alloc->id1.bitmap1.i_total);
  	fi->ifi_stat[slot].lfi_free =
  		le32_to_cpu(dinode_alloc->id1.bitmap1.i_total) -
  		le32_to_cpu(dinode_alloc->id1.bitmap1.i_used);
  
  bail:
  	if (unlock)
  		ocfs2_inode_unlock(inode_alloc, 0);
  
  	if (inode_alloc)
  		mutex_unlock(&inode_alloc->i_mutex);
  
  	brelse(bh);
  
  	return status;
  }
  
  int ocfs2_info_handle_freeinode(struct inode *inode,
  				struct ocfs2_info_request __user *req)
  {
  	u32 i;
  	u64 blkno = -1;
  	char namebuf[40];
  	int status = -EFAULT, type = INODE_ALLOC_SYSTEM_INODE;
  	struct ocfs2_info_freeinode *oifi = NULL;
  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  	struct inode *inode_alloc = NULL;
  
  	oifi = kzalloc(sizeof(struct ocfs2_info_freeinode), GFP_KERNEL);
  	if (!oifi) {
  		status = -ENOMEM;
  		mlog_errno(status);

  		goto out_err;

  	}
  
  	if (o2info_from_user(*oifi, req))
  		goto bail;
  
  	oifi->ifi_slotnum = osb->max_slots;
  
  	for (i = 0; i < oifi->ifi_slotnum; i++) {
  		if (o2info_coherent(&oifi->ifi_req)) {
  			inode_alloc = ocfs2_get_system_file_inode(osb, type, i);
  			if (!inode_alloc) {
  				mlog(ML_ERROR, "unable to get alloc inode in "
  				    "slot %u
  ", i);
  				status = -EIO;
  				goto bail;
  			}
  		} else {
  			ocfs2_sprintf_system_inode_name(namebuf,
  							sizeof(namebuf),
  							type, i);
  			status = ocfs2_lookup_ino_from_name(osb->sys_root_inode,
  							    namebuf,
  							    strlen(namebuf),
  							    &blkno);
  			if (status < 0) {
  				status = -ENOENT;
  				goto bail;
  			}
  		}
  
  		status = ocfs2_info_scan_inode_alloc(osb, inode_alloc, blkno, oifi, i);
  		if (status < 0)
  			goto bail;
  
  		iput(inode_alloc);
  		inode_alloc = NULL;
  	}
  
  	o2info_set_request_filled(&oifi->ifi_req);
  
  	if (o2info_to_user(*oifi, req))
  		goto bail;
  
  	status = 0;
  bail:
  	if (status)
  		o2info_set_request_error(&oifi->ifi_req, req);
  
  	kfree(oifi);

  out_err:

  	return status;
  }

  static void o2ffg_update_histogram(struct ocfs2_info_free_chunk_list *hist,
  				   unsigned int chunksize)
  {
  	int index;
  
  	index = __ilog2_u32(chunksize);
  	if (index >= OCFS2_INFO_MAX_HIST)
  		index = OCFS2_INFO_MAX_HIST - 1;
  
  	hist->fc_chunks[index]++;
  	hist->fc_clusters[index] += chunksize;
  }
  
  static void o2ffg_update_stats(struct ocfs2_info_freefrag_stats *stats,
  			       unsigned int chunksize)
  {
  	if (chunksize > stats->ffs_max)
  		stats->ffs_max = chunksize;
  
  	if (chunksize < stats->ffs_min)
  		stats->ffs_min = chunksize;
  
  	stats->ffs_avg += chunksize;
  	stats->ffs_free_chunks_real++;
  }
  
  void ocfs2_info_update_ffg(struct ocfs2_info_freefrag *ffg,
  			   unsigned int chunksize)
  {
  	o2ffg_update_histogram(&(ffg->iff_ffs.ffs_fc_hist), chunksize);
  	o2ffg_update_stats(&(ffg->iff_ffs), chunksize);
  }
  
  int ocfs2_info_freefrag_scan_chain(struct ocfs2_super *osb,
  				   struct inode *gb_inode,
  				   struct ocfs2_dinode *gb_dinode,
  				   struct ocfs2_chain_rec *rec,
  				   struct ocfs2_info_freefrag *ffg,
  				   u32 chunks_in_group)
  {
  	int status = 0, used;
  	u64 blkno;
  
  	struct buffer_head *bh = NULL;
  	struct ocfs2_group_desc *bg = NULL;
  
  	unsigned int max_bits, num_clusters;
  	unsigned int offset = 0, cluster, chunk;
  	unsigned int chunk_free, last_chunksize = 0;
  
  	if (!le32_to_cpu(rec->c_free))
  		goto bail;
  
  	do {
  		if (!bg)
  			blkno = le64_to_cpu(rec->c_blkno);
  		else
  			blkno = le64_to_cpu(bg->bg_next_group);
  
  		if (bh) {
  			brelse(bh);
  			bh = NULL;
  		}
  
  		if (o2info_coherent(&ffg->iff_req))
  			status = ocfs2_read_group_descriptor(gb_inode,
  							     gb_dinode,
  							     blkno, &bh);
  		else
  			status = ocfs2_read_blocks_sync(osb, blkno, 1, &bh);
  
  		if (status < 0) {
  			mlog(ML_ERROR, "Can't read the group descriptor # "
  			     "%llu from device.", (unsigned long long)blkno);
  			status = -EIO;
  			goto bail;
  		}
  
  		bg = (struct ocfs2_group_desc *)bh->b_data;
  
  		if (!le16_to_cpu(bg->bg_free_bits_count))
  			continue;
  
  		max_bits = le16_to_cpu(bg->bg_bits);
  		offset = 0;
  
  		for (chunk = 0; chunk < chunks_in_group; chunk++) {
  			/*
  			 * last chunk may be not an entire one.
  			 */
  			if ((offset + ffg->iff_chunksize) > max_bits)
  				num_clusters = max_bits - offset;
  			else
  				num_clusters = ffg->iff_chunksize;
  
  			chunk_free = 0;
  			for (cluster = 0; cluster < num_clusters; cluster++) {
  				used = ocfs2_test_bit(offset,
  						(unsigned long *)bg->bg_bitmap);
  				/*
  				 * - chunk_free counts free clusters in #N chunk.
  				 * - last_chunksize records the size(in) clusters
  				 *   for the last real free chunk being counted.
  				 */
  				if (!used) {
  					last_chunksize++;
  					chunk_free++;
  				}
  
  				if (used && last_chunksize) {
  					ocfs2_info_update_ffg(ffg,
  							      last_chunksize);
  					last_chunksize = 0;
  				}
  
  				offset++;
  			}
  
  			if (chunk_free == ffg->iff_chunksize)
  				ffg->iff_ffs.ffs_free_chunks++;
  		}
  
  		/*
  		 * need to update the info for last free chunk.
  		 */
  		if (last_chunksize)
  			ocfs2_info_update_ffg(ffg, last_chunksize);
  
  	} while (le64_to_cpu(bg->bg_next_group));
  
  bail:
  	brelse(bh);
  
  	return status;
  }
  
  int ocfs2_info_freefrag_scan_bitmap(struct ocfs2_super *osb,
  				    struct inode *gb_inode, u64 blkno,
  				    struct ocfs2_info_freefrag *ffg)
  {
  	u32 chunks_in_group;
  	int status = 0, unlock = 0, i;
  
  	struct buffer_head *bh = NULL;
  	struct ocfs2_chain_list *cl = NULL;
  	struct ocfs2_chain_rec *rec = NULL;
  	struct ocfs2_dinode *gb_dinode = NULL;
  
  	if (gb_inode)
  		mutex_lock(&gb_inode->i_mutex);
  
  	if (o2info_coherent(&ffg->iff_req)) {
  		status = ocfs2_inode_lock(gb_inode, &bh, 0);
  		if (status < 0) {
  			mlog_errno(status);
  			goto bail;
  		}
  		unlock = 1;
  	} else {
  		status = ocfs2_read_blocks_sync(osb, blkno, 1, &bh);
  		if (status < 0) {
  			mlog_errno(status);
  			goto bail;
  		}
  	}
  
  	gb_dinode = (struct ocfs2_dinode *)bh->b_data;
  	cl = &(gb_dinode->id2.i_chain);
  
  	/*
  	 * Chunksize(in) clusters from userspace should be
  	 * less than clusters in a group.
  	 */
  	if (ffg->iff_chunksize > le16_to_cpu(cl->cl_cpg)) {
  		status = -EINVAL;
  		goto bail;
  	}
  
  	memset(&ffg->iff_ffs, 0, sizeof(struct ocfs2_info_freefrag_stats));
  
  	ffg->iff_ffs.ffs_min = ~0U;
  	ffg->iff_ffs.ffs_clusters =
  			le32_to_cpu(gb_dinode->id1.bitmap1.i_total);
  	ffg->iff_ffs.ffs_free_clusters = ffg->iff_ffs.ffs_clusters -
  			le32_to_cpu(gb_dinode->id1.bitmap1.i_used);
  
  	chunks_in_group = le16_to_cpu(cl->cl_cpg) / ffg->iff_chunksize + 1;
  
  	for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i++) {
  		rec = &(cl->cl_recs[i]);
  		status = ocfs2_info_freefrag_scan_chain(osb, gb_inode,
  							gb_dinode,
  							rec, ffg,
  							chunks_in_group);
  		if (status)
  			goto bail;
  	}
  
  	if (ffg->iff_ffs.ffs_free_chunks_real)
  		ffg->iff_ffs.ffs_avg = (ffg->iff_ffs.ffs_avg /
  					ffg->iff_ffs.ffs_free_chunks_real);
  bail:
  	if (unlock)
  		ocfs2_inode_unlock(gb_inode, 0);
  
  	if (gb_inode)
  		mutex_unlock(&gb_inode->i_mutex);
  
  	if (gb_inode)
  		iput(gb_inode);
  
  	brelse(bh);
  
  	return status;
  }
  
  int ocfs2_info_handle_freefrag(struct inode *inode,
  			       struct ocfs2_info_request __user *req)
  {
  	u64 blkno = -1;
  	char namebuf[40];
  	int status = -EFAULT, type = GLOBAL_BITMAP_SYSTEM_INODE;
  
  	struct ocfs2_info_freefrag *oiff;
  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  	struct inode *gb_inode = NULL;
  
  	oiff = kzalloc(sizeof(struct ocfs2_info_freefrag), GFP_KERNEL);
  	if (!oiff) {
  		status = -ENOMEM;
  		mlog_errno(status);

  		goto out_err;

  	}
  
  	if (o2info_from_user(*oiff, req))
  		goto bail;
  	/*
  	 * chunksize from userspace should be power of 2.
  	 */
  	if ((oiff->iff_chunksize & (oiff->iff_chunksize - 1)) ||
  	    (!oiff->iff_chunksize)) {
  		status = -EINVAL;
  		goto bail;
  	}
  
  	if (o2info_coherent(&oiff->iff_req)) {
  		gb_inode = ocfs2_get_system_file_inode(osb, type,
  						       OCFS2_INVALID_SLOT);
  		if (!gb_inode) {
  			mlog(ML_ERROR, "unable to get global_bitmap inode
  ");
  			status = -EIO;
  			goto bail;
  		}
  	} else {
  		ocfs2_sprintf_system_inode_name(namebuf, sizeof(namebuf), type,
  						OCFS2_INVALID_SLOT);
  		status = ocfs2_lookup_ino_from_name(osb->sys_root_inode,
  						    namebuf,
  						    strlen(namebuf),
  						    &blkno);
  		if (status < 0) {
  			status = -ENOENT;
  			goto bail;
  		}
  	}
  
  	status = ocfs2_info_freefrag_scan_bitmap(osb, gb_inode, blkno, oiff);
  	if (status < 0)
  		goto bail;
  
  	o2info_set_request_filled(&oiff->iff_req);
  
  	if (o2info_to_user(*oiff, req))
  		goto bail;
  
  	status = 0;
  bail:
  	if (status)
  		o2info_set_request_error(&oiff->iff_req, req);
  
  	kfree(oiff);

  out_err:

  	return status;
  }
  
  int ocfs2_info_handle_unknown(struct inode *inode,
  			      struct ocfs2_info_request __user *req)
  {
  	int status = -EFAULT;
  	struct ocfs2_info_request oir;
  
  	if (o2info_from_user(oir, req))
  		goto bail;

  	o2info_clear_request_filled(&oir);

  
  	if (o2info_to_user(oir, req))
  		goto bail;
  
  	status = 0;
  bail:
  	if (status)

  		o2info_set_request_error(&oir, req);

  
  	return status;
  }
  
  /*
   * Validate and distinguish OCFS2_IOC_INFO requests.
   *
   * - validate the magic number.
   * - distinguish different requests.
   * - validate size of different requests.
   */
  int ocfs2_info_handle_request(struct inode *inode,
  			      struct ocfs2_info_request __user *req)
  {
  	int status = -EFAULT;
  	struct ocfs2_info_request oir;
  
  	if (o2info_from_user(oir, req))
  		goto bail;
  
  	status = -EINVAL;
  	if (oir.ir_magic != OCFS2_INFO_MAGIC)
  		goto bail;
  
  	switch (oir.ir_code) {
  	case OCFS2_INFO_BLOCKSIZE:
  		if (oir.ir_size == sizeof(struct ocfs2_info_blocksize))
  			status = ocfs2_info_handle_blocksize(inode, req);
  		break;
  	case OCFS2_INFO_CLUSTERSIZE:
  		if (oir.ir_size == sizeof(struct ocfs2_info_clustersize))
  			status = ocfs2_info_handle_clustersize(inode, req);
  		break;
  	case OCFS2_INFO_MAXSLOTS:
  		if (oir.ir_size == sizeof(struct ocfs2_info_maxslots))
  			status = ocfs2_info_handle_maxslots(inode, req);
  		break;
  	case OCFS2_INFO_LABEL:
  		if (oir.ir_size == sizeof(struct ocfs2_info_label))
  			status = ocfs2_info_handle_label(inode, req);
  		break;
  	case OCFS2_INFO_UUID:
  		if (oir.ir_size == sizeof(struct ocfs2_info_uuid))
  			status = ocfs2_info_handle_uuid(inode, req);
  		break;
  	case OCFS2_INFO_FS_FEATURES:
  		if (oir.ir_size == sizeof(struct ocfs2_info_fs_features))
  			status = ocfs2_info_handle_fs_features(inode, req);
  		break;
  	case OCFS2_INFO_JOURNAL_SIZE:
  		if (oir.ir_size == sizeof(struct ocfs2_info_journal_size))
  			status = ocfs2_info_handle_journal_size(inode, req);
  		break;

  	case OCFS2_INFO_FREEINODE:
  		if (oir.ir_size == sizeof(struct ocfs2_info_freeinode))
  			status = ocfs2_info_handle_freeinode(inode, req);
  		break;

  	case OCFS2_INFO_FREEFRAG:
  		if (oir.ir_size == sizeof(struct ocfs2_info_freefrag))
  			status = ocfs2_info_handle_freefrag(inode, req);
  		break;

  	default:
  		status = ocfs2_info_handle_unknown(inode, req);
  		break;
  	}
  
  bail:
  	return status;
  }
  
  int ocfs2_get_request_ptr(struct ocfs2_info *info, int idx,
  			  u64 *req_addr, int compat_flag)
  {
  	int status = -EFAULT;
  	u64 __user *bp = NULL;
  
  	if (compat_flag) {
  #ifdef CONFIG_COMPAT
  		/*
  		 * pointer bp stores the base address of a pointers array,
  		 * which collects all addresses of separate request.
  		 */
  		bp = (u64 __user *)(unsigned long)compat_ptr(info->oi_requests);
  #else
  		BUG();
  #endif
  	} else
  		bp = (u64 __user *)(unsigned long)(info->oi_requests);
  
  	if (o2info_from_user(*req_addr, bp + idx))
  		goto bail;
  
  	status = 0;
  bail:
  	return status;
  }
  
  /*
   * OCFS2_IOC_INFO handles an array of requests passed from userspace.
   *
   * ocfs2_info_handle() recevies a large info aggregation, grab and
   * validate the request count from header, then break it into small
   * pieces, later specific handlers can handle them one by one.
   *
   * Idea here is to make each separate request small enough to ensure
   * a better backward&forward compatibility, since a small piece of
   * request will be less likely to be broken if disk layout get changed.
   */
  int ocfs2_info_handle(struct inode *inode, struct ocfs2_info *info,
  		      int compat_flag)
  {
  	int i, status = 0;
  	u64 req_addr;
  	struct ocfs2_info_request __user *reqp;
  
  	if ((info->oi_count > OCFS2_INFO_MAX_REQUEST) ||
  	    (!info->oi_requests)) {
  		status = -EINVAL;
  		goto bail;
  	}
  
  	for (i = 0; i < info->oi_count; i++) {
  
  		status = ocfs2_get_request_ptr(info, i, &req_addr, compat_flag);
  		if (status)
  			break;
  
  		reqp = (struct ocfs2_info_request *)(unsigned long)req_addr;
  		if (!reqp) {
  			status = -EINVAL;
  			goto bail;
  		}
  
  		status = ocfs2_info_handle_request(inode, reqp);
  		if (status)
  			break;
  	}
  
  bail:
  	return status;
  }

  long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)

  {

  	struct inode *inode = filp->f_path.dentry->d_inode;

  	unsigned int flags;

  	int new_clusters;

  	int status;

  	struct ocfs2_space_resv sr;

  	struct ocfs2_new_group_input input;

  	struct reflink_arguments args;
  	const char *old_path, *new_path;
  	bool preserve;

  	struct ocfs2_info info;

  
  	switch (cmd) {
  	case OCFS2_IOC_GETFLAGS:
  		status = ocfs2_get_inode_attr(inode, &flags);
  		if (status < 0)
  			return status;
  
  		flags &= OCFS2_FL_VISIBLE;
  		return put_user(flags, (int __user *) arg);
  	case OCFS2_IOC_SETFLAGS:
  		if (get_user(flags, (int __user *) arg))
  			return -EFAULT;

  		status = mnt_want_write_file(filp);

  		if (status)
  			return status;
  		status = ocfs2_set_inode_attr(inode, flags,

  			OCFS2_FL_MODIFIABLE);

  		mnt_drop_write_file(filp);

  		return status;

  	case OCFS2_IOC_RESVSP:
  	case OCFS2_IOC_RESVSP64:
  	case OCFS2_IOC_UNRESVSP:
  	case OCFS2_IOC_UNRESVSP64:
  		if (copy_from_user(&sr, (int __user *) arg, sizeof(sr)))
  			return -EFAULT;
  
  		return ocfs2_change_file_space(filp, cmd, &sr);

  	case OCFS2_IOC_GROUP_EXTEND:

  		if (!capable(CAP_SYS_RESOURCE))
  			return -EPERM;

  		if (get_user(new_clusters, (int __user *)arg))
  			return -EFAULT;
  
  		return ocfs2_group_extend(inode, new_clusters);

  	case OCFS2_IOC_GROUP_ADD:
  	case OCFS2_IOC_GROUP_ADD64:

  		if (!capable(CAP_SYS_RESOURCE))
  			return -EPERM;

  		if (copy_from_user(&input, (int __user *) arg, sizeof(input)))
  			return -EFAULT;
  
  		return ocfs2_group_add(inode, &input);

  	case OCFS2_IOC_REFLINK:
  		if (copy_from_user(&args, (struct reflink_arguments *)arg,
  				   sizeof(args)))
  			return -EFAULT;
  		old_path = (const char *)(unsigned long)args.old_path;
  		new_path = (const char *)(unsigned long)args.new_path;
  		preserve = (args.preserve != 0);
  
  		return ocfs2_reflink_ioctl(inode, old_path, new_path, preserve);

  	case OCFS2_IOC_INFO:
  		if (copy_from_user(&info, (struct ocfs2_info __user *)arg,
  				   sizeof(struct ocfs2_info)))
  			return -EFAULT;
  
  		return ocfs2_info_handle(inode, &info, 0);

  	case FITRIM:
  	{
  		struct super_block *sb = inode->i_sb;
  		struct fstrim_range range;
  		int ret = 0;
  
  		if (!capable(CAP_SYS_ADMIN))
  			return -EPERM;
  
  		if (copy_from_user(&range, (struct fstrim_range *)arg,
  		    sizeof(range)))
  			return -EFAULT;
  
  		ret = ocfs2_trim_fs(sb, &range);
  		if (ret < 0)
  			return ret;
  
  		if (copy_to_user((struct fstrim_range *)arg, &range,
  		    sizeof(range)))
  			return -EFAULT;
  
  		return 0;
  	}

  	case OCFS2_IOC_MOVE_EXT:
  		return ocfs2_ioctl_move_extents(filp, (void __user *)arg);

  	default:
  		return -ENOTTY;
  	}
  }

  #ifdef CONFIG_COMPAT
  long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg)
  {

  	bool preserve;
  	struct reflink_arguments args;
  	struct inode *inode = file->f_path.dentry->d_inode;

  	struct ocfs2_info info;

  	switch (cmd) {
  	case OCFS2_IOC32_GETFLAGS:
  		cmd = OCFS2_IOC_GETFLAGS;
  		break;
  	case OCFS2_IOC32_SETFLAGS:
  		cmd = OCFS2_IOC_SETFLAGS;
  		break;

  	case OCFS2_IOC_RESVSP:
  	case OCFS2_IOC_RESVSP64:
  	case OCFS2_IOC_UNRESVSP:
  	case OCFS2_IOC_UNRESVSP64:

  	case OCFS2_IOC_GROUP_EXTEND:

  	case OCFS2_IOC_GROUP_ADD:
  	case OCFS2_IOC_GROUP_ADD64:

  	case FITRIM:

  		break;

  	case OCFS2_IOC_REFLINK:
  		if (copy_from_user(&args, (struct reflink_arguments *)arg,
  				   sizeof(args)))
  			return -EFAULT;
  		preserve = (args.preserve != 0);
  
  		return ocfs2_reflink_ioctl(inode, compat_ptr(args.old_path),
  					   compat_ptr(args.new_path), preserve);

  	case OCFS2_IOC_INFO:
  		if (copy_from_user(&info, (struct ocfs2_info __user *)arg,
  				   sizeof(struct ocfs2_info)))
  			return -EFAULT;
  
  		return ocfs2_info_handle(inode, &info, 1);

  	case OCFS2_IOC_MOVE_EXT:
  		break;

  	default:
  		return -ENOIOCTLCMD;
  	}

  	return ocfs2_ioctl(file, cmd, arg);

  }
  #endif