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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * file.c
  *
  * File open, close, extend, truncate
  *
  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
  */
 
 #include <linux/capability.h>
 #include <linux/fs.h>
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>
 #include <linux/pagemap.h>
 #include <linux/uio.h>
 #include <linux/sched.h>
 #include <linux/splice.h>
 #include <linux/mount.h>
 #include <linux/writeback.h>
 #include <linux/falloc.h>
 #include <linux/quotaops.h>
 #include <linux/blkdev.h>
 #include <linux/backing-dev.h>
 
 #include <cluster/masklog.h>
 
 #include "ocfs2.h"
 
 #include "alloc.h"
 #include "aops.h"
 #include "dir.h"
 #include "dlmglue.h"
 #include "extent_map.h"
 #include "file.h"
 #include "sysfile.h"
 #include "inode.h"
 #include "ioctl.h"
 #include "journal.h"
 #include "locks.h"
 #include "mmap.h"
 #include "suballoc.h"
 #include "super.h"
 #include "xattr.h"
 #include "acl.h"
 #include "quota.h"
 #include "refcounttree.h"
 #include "ocfs2_trace.h"
 
 #include "buffer_head_io.h"
 
 static int ocfs2_init_file_private(struct inode *inode, struct file *file)
 {
     struct ocfs2_file_private *fp;
 
     fp = kzalloc(sizeof(struct ocfs2_file_private), GFP_KERNEL);
     if (!fp)
         return -ENOMEM;
 
     fp->fp_file = file;
     mutex_init(&fp->fp_mutex);
     ocfs2_file_lock_res_init(&fp->fp_flock, fp);
     file->private_data = fp;
 
     return 0;
 }
 
 static void ocfs2_free_file_private(struct inode *inode, struct file *file)
 {
     struct ocfs2_file_private *fp = file->private_data;
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 
     if (fp) {
         ocfs2_simple_drop_lockres(osb, &fp->fp_flock);
         ocfs2_lock_res_free(&fp->fp_flock);
         kfree(fp);
         file->private_data = NULL;
     }
 }
 
 static int ocfs2_file_open(struct inode *inode, struct file *file)
 {
     int status;
     int mode = file->f_flags;
     struct ocfs2_inode_info *oi = OCFS2_I(inode);
 
     trace_ocfs2_file_open(inode, file, file->f_path.dentry,
                   (unsigned long long)oi->ip_blkno,
                   file->f_path.dentry->d_name.len,
                   file->f_path.dentry->d_name.name, mode);
 
     if (file->f_mode & FMODE_WRITE) {
         status = dquot_initialize(inode);
         if (status)
             goto leave;
     }
 
     spin_lock(&oi->ip_lock);
 
     /* Check that the inode hasn't been wiped from disk by another
      * node. If it hasn't then we're safe as long as we hold the
      * spin lock until our increment of open count. */
     if (oi->ip_flags & OCFS2_INODE_DELETED) {
         spin_unlock(&oi->ip_lock);
 
         status = -ENOENT;
         goto leave;
     }
 
     if (mode & O_DIRECT)
         oi->ip_flags |= OCFS2_INODE_OPEN_DIRECT;
 
     oi->ip_open_count++;
     spin_unlock(&oi->ip_lock);
 
     status = ocfs2_init_file_private(inode, file);
     if (status) {
         /*
          * We want to set open count back if we're failing the
          * open.
          */
         spin_lock(&oi->ip_lock);
         oi->ip_open_count--;
         spin_unlock(&oi->ip_lock);
     }
 
     file->f_mode |= FMODE_NOWAIT;
 
 leave:
     return status;
 }
 
 static int ocfs2_file_release(struct inode *inode, struct file *file)
 {
     struct ocfs2_inode_info *oi = OCFS2_I(inode);
 
     spin_lock(&oi->ip_lock);
     if (!--oi->ip_open_count)
         oi->ip_flags &= ~OCFS2_INODE_OPEN_DIRECT;
 
     trace_ocfs2_file_release(inode, file, file->f_path.dentry,
                  oi->ip_blkno,
                  file->f_path.dentry->d_name.len,
                  file->f_path.dentry->d_name.name,
                  oi->ip_open_count);
     spin_unlock(&oi->ip_lock);
 
     ocfs2_free_file_private(inode, file);
 
     return 0;
 }
 
 static int ocfs2_dir_open(struct inode *inode, struct file *file)
 {
     return ocfs2_init_file_private(inode, file);
 }
 
 static int ocfs2_dir_release(struct inode *inode, struct file *file)
 {
     ocfs2_free_file_private(inode, file);
     return 0;
 }
 
 static int ocfs2_sync_file(struct file *file, loff_t start, loff_t end,
                int datasync)
 {
     int err = 0;
     struct inode *inode = file->f_mapping->host;
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     struct ocfs2_inode_info *oi = OCFS2_I(inode);
     journal_t *journal = osb->journal->j_journal;
     int ret;
     tid_t commit_tid;
     bool needs_barrier = false;
 
     trace_ocfs2_sync_file(inode, file, file->f_path.dentry,
                   oi->ip_blkno,
                   file->f_path.dentry->d_name.len,
                   file->f_path.dentry->d_name.name,
                   (unsigned long long)datasync);
 
     if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
         return -EROFS;
 
     err = file_write_and_wait_range(file, start, end);
     if (err)
         return err;
 
     commit_tid = datasync ? oi->i_datasync_tid : oi->i_sync_tid;
     if (journal->j_flags & JBD2_BARRIER &&
         !jbd2_trans_will_send_data_barrier(journal, commit_tid))
         needs_barrier = true;
     err = jbd2_complete_transaction(journal, commit_tid);
     if (needs_barrier) {
         ret = blkdev_issue_flush(inode->i_sb->s_bdev);
         if (!err)
             err = ret;
     }
 
     if (err)
         mlog_errno(err);
 
     return (err < 0) ? -EIO : 0;
 }
 
 int ocfs2_should_update_atime(struct inode *inode,
                   struct vfsmount *vfsmnt)
 {
     struct timespec64 now;
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 
     if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
         return 0;
 
     if ((inode->i_flags & S_NOATIME) ||
         ((inode->i_sb->s_flags & SB_NODIRATIME) && S_ISDIR(inode->i_mode)))
         return 0;
 
     /*
      * We can be called with no vfsmnt structure - NFSD will
      * sometimes do this.
      *
      * Note that our action here is different than touch_atime() -
      * if we can't tell whether this is a noatime mount, then we
      * don't know whether to trust the value of s_atime_quantum.
      */
     if (vfsmnt == NULL)
         return 0;
 
     if ((vfsmnt->mnt_flags & MNT_NOATIME) ||
         ((vfsmnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
         return 0;
 
     if (vfsmnt->mnt_flags & MNT_RELATIME) {
         if ((timespec64_compare(&inode->i_atime, &inode->i_mtime) <= 0) ||
             (timespec64_compare(&inode->i_atime, &inode->i_ctime) <= 0))
             return 1;
 
         return 0;
     }
 
     now = current_time(inode);
     if ((now.tv_sec - inode->i_atime.tv_sec <= osb->s_atime_quantum))
         return 0;
     else
         return 1;
 }
 
 int ocfs2_update_inode_atime(struct inode *inode,
                  struct buffer_head *bh)
 {
     int ret;
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     handle_t *handle;
     struct ocfs2_dinode *di = (struct ocfs2_dinode *) bh->b_data;
 
     handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
     if (IS_ERR(handle)) {
         ret = PTR_ERR(handle);
         mlog_errno(ret);
         goto out;
     }
 
     ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), bh,
                       OCFS2_JOURNAL_ACCESS_WRITE);
     if (ret) {
         mlog_errno(ret);
         goto out_commit;
     }
 
     /*
      * Don't use ocfs2_mark_inode_dirty() here as we don't always
      * have i_rwsem to guard against concurrent changes to other
      * inode fields.
      */
     inode->i_atime = current_time(inode);
     di->i_atime = cpu_to_le64(inode->i_atime.tv_sec);
     di->i_atime_nsec = cpu_to_le32(inode->i_atime.tv_nsec);
     ocfs2_update_inode_fsync_trans(handle, inode, 0);
     ocfs2_journal_dirty(handle, bh);
 
 out_commit:
     ocfs2_commit_trans(osb, handle);
 out:
     return ret;
 }
 
 int ocfs2_set_inode_size(handle_t *handle,
                 struct inode *inode,
                 struct buffer_head *fe_bh,
                 u64 new_i_size)
 {
     int status;
 
     i_size_write(inode, new_i_size);
     inode->i_blocks = ocfs2_inode_sector_count(inode);
     inode->i_ctime = inode->i_mtime = current_time(inode);
 
     status = ocfs2_mark_inode_dirty(handle, inode, fe_bh);
     if (status < 0) {
         mlog_errno(status);
         goto bail;
     }
 
 bail:
     return status;
 }
 
 int ocfs2_simple_size_update(struct inode *inode,
                  struct buffer_head *di_bh,
                  u64 new_i_size)
 {
     int ret;
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     handle_t *handle = NULL;
 
     handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
     if (IS_ERR(handle)) {
         ret = PTR_ERR(handle);
         mlog_errno(ret);
         goto out;
     }
 
     ret = ocfs2_set_inode_size(handle, inode, di_bh,
                    new_i_size);
     if (ret < 0)
         mlog_errno(ret);
 
     ocfs2_update_inode_fsync_trans(handle, inode, 0);
     ocfs2_commit_trans(osb, handle);
 out:
     return ret;
 }
 
 static int ocfs2_cow_file_pos(struct inode *inode,
                   struct buffer_head *fe_bh,
                   u64 offset)
 {
     int status;
     u32 phys, cpos = offset >> OCFS2_SB(inode->i_sb)->s_clustersize_bits;
     unsigned int num_clusters = 0;
     unsigned int ext_flags = 0;
 
     /*
      * If the new offset is aligned to the range of the cluster, there is
      * no space for ocfs2_zero_range_for_truncate to fill, so no need to
      * CoW either.
      */
     if ((offset & (OCFS2_SB(inode->i_sb)->s_clustersize - 1)) == 0)
         return 0;
 
     status = ocfs2_get_clusters(inode, cpos, &phys,
                     &num_clusters, &ext_flags);
     if (status) {
         mlog_errno(status);
         goto out;
     }
 
     if (!(ext_flags & OCFS2_EXT_REFCOUNTED))
         goto out;
 
     return ocfs2_refcount_cow(inode, fe_bh, cpos, 1, cpos+1);
 
 out:
     return status;
 }
 
 static int ocfs2_orphan_for_truncate(struct ocfs2_super *osb,
                      struct inode *inode,
                      struct buffer_head *fe_bh,
                      u64 new_i_size)
 {
     int status;
     handle_t *handle;
     struct ocfs2_dinode *di;
     u64 cluster_bytes;
 
     /*
      * We need to CoW the cluster contains the offset if it is reflinked
      * since we will call ocfs2_zero_range_for_truncate later which will
      * write "0" from offset to the end of the cluster.
      */
     status = ocfs2_cow_file_pos(inode, fe_bh, new_i_size);
     if (status) {
         mlog_errno(status);
         return status;
     }
 
     /* TODO: This needs to actually orphan the inode in this
      * transaction. */
 
     handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
     if (IS_ERR(handle)) {
         status = PTR_ERR(handle);
         mlog_errno(status);
         goto out;
     }
 
     status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), fe_bh,
                      OCFS2_JOURNAL_ACCESS_WRITE);
     if (status < 0) {
         mlog_errno(status);
         goto out_commit;
     }
 
     /*
      * Do this before setting i_size.
      */
     cluster_bytes = ocfs2_align_bytes_to_clusters(inode->i_sb, new_i_size);
     status = ocfs2_zero_range_for_truncate(inode, handle, new_i_size,
                            cluster_bytes);
     if (status) {
         mlog_errno(status);
         goto out_commit;
     }
 
     i_size_write(inode, new_i_size);
     inode->i_ctime = inode->i_mtime = current_time(inode);
 
     di = (struct ocfs2_dinode *) fe_bh->b_data;
     di->i_size = cpu_to_le64(new_i_size);
     di->i_ctime = di->i_mtime = cpu_to_le64(inode->i_ctime.tv_sec);
     di->i_ctime_nsec = di->i_mtime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
     ocfs2_update_inode_fsync_trans(handle, inode, 0);
 
     ocfs2_journal_dirty(handle, fe_bh);
 
 out_commit:
     ocfs2_commit_trans(osb, handle);
 out:
     return status;
 }
 
 int ocfs2_truncate_file(struct inode *inode,
                    struct buffer_head *di_bh,
                    u64 new_i_size)
 {
     int status = 0;
     struct ocfs2_dinode *fe = NULL;
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 
     /* We trust di_bh because it comes from ocfs2_inode_lock(), which
      * already validated it */
     fe = (struct ocfs2_dinode *) di_bh->b_data;
 
     trace_ocfs2_truncate_file((unsigned long long)OCFS2_I(inode)->ip_blkno,
                   (unsigned long long)le64_to_cpu(fe->i_size),
                   (unsigned long long)new_i_size);
 
     mlog_bug_on_msg(le64_to_cpu(fe->i_size) != i_size_read(inode),
             "Inode %llu, inode i_size = %lld != di "
             "i_size = %llu, i_flags = 0x%x\n",
             (unsigned long long)OCFS2_I(inode)->ip_blkno,
             i_size_read(inode),
             (unsigned long long)le64_to_cpu(fe->i_size),
             le32_to_cpu(fe->i_flags));
 
     if (new_i_size > le64_to_cpu(fe->i_size)) {
         trace_ocfs2_truncate_file_error(
             (unsigned long long)le64_to_cpu(fe->i_size),
             (unsigned long long)new_i_size);
         status = -EINVAL;
         mlog_errno(status);
         goto bail;
     }
 
     down_write(&OCFS2_I(inode)->ip_alloc_sem);
 
     ocfs2_resv_discard(&osb->osb_la_resmap,
                &OCFS2_I(inode)->ip_la_data_resv);
 
     /*
      * The inode lock forced other nodes to sync and drop their
      * pages, which (correctly) happens even if we have a truncate
      * without allocation change - ocfs2 cluster sizes can be much
      * greater than page size, so we have to truncate them
      * anyway.
      */
 
     if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
         unmap_mapping_range(inode->i_mapping,
                     new_i_size + PAGE_SIZE - 1, 0, 1);
         truncate_inode_pages(inode->i_mapping, new_i_size);
         status = ocfs2_truncate_inline(inode, di_bh, new_i_size,
                            i_size_read(inode), 1);
         if (status)
             mlog_errno(status);
 
         goto bail_unlock_sem;
     }
 
     /* alright, we're going to need to do a full blown alloc size
      * change. Orphan the inode so that recovery can complete the
      * truncate if necessary. This does the task of marking
      * i_size. */
     status = ocfs2_orphan_for_truncate(osb, inode, di_bh, new_i_size);
     if (status < 0) {
         mlog_errno(status);
         goto bail_unlock_sem;
     }
 
     unmap_mapping_range(inode->i_mapping, new_i_size + PAGE_SIZE - 1, 0, 1);
     truncate_inode_pages(inode->i_mapping, new_i_size);
 
     status = ocfs2_commit_truncate(osb, inode, di_bh);
     if (status < 0) {
         mlog_errno(status);
         goto bail_unlock_sem;
     }
 
     /* TODO: orphan dir cleanup here. */
 bail_unlock_sem:
     up_write(&OCFS2_I(inode)->ip_alloc_sem);
 
 bail:
     if (!status && OCFS2_I(inode)->ip_clusters == 0)
         status = ocfs2_try_remove_refcount_tree(inode, di_bh);
 
     return status;
 }
 
 /*
  * extend file allocation only here.
  * we'll update all the disk stuff, and oip->alloc_size
  *
  * expect stuff to be locked, a transaction started and enough data /
  * metadata reservations in the contexts.
  *
  * Will return -EAGAIN, and a reason if a restart is needed.
  * If passed in, *reason will always be set, even in error.
  */
 int ocfs2_add_inode_data(struct ocfs2_super *osb,
              struct inode *inode,
              u32 *logical_offset,
              u32 clusters_to_add,
              int mark_unwritten,
              struct buffer_head *fe_bh,
              handle_t *handle,
              struct ocfs2_alloc_context *data_ac,
              struct ocfs2_alloc_context *meta_ac,
              enum ocfs2_alloc_restarted *reason_ret)
 {
     struct ocfs2_extent_tree et;
 
     ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), fe_bh);
     return ocfs2_add_clusters_in_btree(handle, &et, logical_offset,
                        clusters_to_add, mark_unwritten,
                        data_ac, meta_ac, reason_ret);
 }
 
 static int ocfs2_extend_allocation(struct inode *inode, u32 logical_start,
                    u32 clusters_to_add, int mark_unwritten)
 {
     int status = 0;
     int restart_func = 0;
     int credits;
     u32 prev_clusters;
     struct buffer_head *bh = NULL;
     struct ocfs2_dinode *fe = NULL;
     handle_t *handle = NULL;
     struct ocfs2_alloc_context *data_ac = NULL;
     struct ocfs2_alloc_context *meta_ac = NULL;
     enum ocfs2_alloc_restarted why = RESTART_NONE;
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     struct ocfs2_extent_tree et;
     int did_quota = 0;
 
     /*
      * Unwritten extent only exists for file systems which
      * support holes.
      */
     BUG_ON(mark_unwritten && !ocfs2_sparse_alloc(osb));
 
     status = ocfs2_read_inode_block(inode, &bh);
     if (status < 0) {
         mlog_errno(status);
         goto leave;
     }
     fe = (struct ocfs2_dinode *) bh->b_data;
 
 restart_all:
     BUG_ON(le32_to_cpu(fe->i_clusters) != OCFS2_I(inode)->ip_clusters);
 
     ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), bh);
     status = ocfs2_lock_allocators(inode, &et, clusters_to_add, 0,
                        &data_ac, &meta_ac);
     if (status) {
         mlog_errno(status);
         goto leave;
     }
 
     credits = ocfs2_calc_extend_credits(osb->sb, &fe->id2.i_list);
     handle = ocfs2_start_trans(osb, credits);
     if (IS_ERR(handle)) {
         status = PTR_ERR(handle);
         handle = NULL;
         mlog_errno(status);
         goto leave;
     }
 
 restarted_transaction:
     trace_ocfs2_extend_allocation(
         (unsigned long long)OCFS2_I(inode)->ip_blkno,
         (unsigned long long)i_size_read(inode),
         le32_to_cpu(fe->i_clusters), clusters_to_add,
         why, restart_func);
 
     status = dquot_alloc_space_nodirty(inode,
             ocfs2_clusters_to_bytes(osb->sb, clusters_to_add));
     if (status)
         goto leave;
     did_quota = 1;
 
     /* reserve a write to the file entry early on - that we if we
      * run out of credits in the allocation path, we can still
      * update i_size. */
     status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), bh,
                      OCFS2_JOURNAL_ACCESS_WRITE);
     if (status < 0) {
         mlog_errno(status);
         goto leave;
     }
 
     prev_clusters = OCFS2_I(inode)->ip_clusters;
 
     status = ocfs2_add_inode_data(osb,
                       inode,
                       &logical_start,
                       clusters_to_add,
                       mark_unwritten,
                       bh,
                       handle,
                       data_ac,
                       meta_ac,
                       &why);
     if ((status < 0) && (status != -EAGAIN)) {
         if (status != -ENOSPC)
             mlog_errno(status);
         goto leave;
     }
     ocfs2_update_inode_fsync_trans(handle, inode, 1);
     ocfs2_journal_dirty(handle, bh);
 
     spin_lock(&OCFS2_I(inode)->ip_lock);
     clusters_to_add -= (OCFS2_I(inode)->ip_clusters - prev_clusters);
     spin_unlock(&OCFS2_I(inode)->ip_lock);
     /* Release unused quota reservation */
     dquot_free_space(inode,
             ocfs2_clusters_to_bytes(osb->sb, clusters_to_add));
     did_quota = 0;
 
     if (why != RESTART_NONE && clusters_to_add) {
         if (why == RESTART_META) {
             restart_func = 1;
             status = 0;
         } else {
             BUG_ON(why != RESTART_TRANS);
 
             status = ocfs2_allocate_extend_trans(handle, 1);
             if (status < 0) {
                 /* handle still has to be committed at
                  * this point. */
                 status = -ENOMEM;
                 mlog_errno(status);
                 goto leave;
             }
             goto restarted_transaction;
         }
     }
 
     trace_ocfs2_extend_allocation_end(OCFS2_I(inode)->ip_blkno,
          le32_to_cpu(fe->i_clusters),
          (unsigned long long)le64_to_cpu(fe->i_size),
          OCFS2_I(inode)->ip_clusters,
          (unsigned long long)i_size_read(inode));
 
 leave:
     if (status < 0 && did_quota)
         dquot_free_space(inode,
             ocfs2_clusters_to_bytes(osb->sb, clusters_to_add));
     if (handle) {
         ocfs2_commit_trans(osb, handle);
         handle = NULL;
     }
     if (data_ac) {
         ocfs2_free_alloc_context(data_ac);
         data_ac = NULL;
     }
     if (meta_ac) {
         ocfs2_free_alloc_context(meta_ac);
         meta_ac = NULL;
     }
     if ((!status) && restart_func) {
         restart_func = 0;
         goto restart_all;
     }
     brelse(bh);
     bh = NULL;
 
     return status;
 }
 
 /*
  * While a write will already be ordering the data, a truncate will not.
  * Thus, we need to explicitly order the zeroed pages.
  */
 static handle_t *ocfs2_zero_start_ordered_transaction(struct inode *inode,
                               struct buffer_head *di_bh,
                               loff_t start_byte,
                               loff_t length)
 {
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     handle_t *handle = NULL;
     int ret = 0;
 
     if (!ocfs2_should_order_data(inode))
         goto out;
 
     handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
     if (IS_ERR(handle)) {
         ret = -ENOMEM;
         mlog_errno(ret);
         goto out;
     }
 
     ret = ocfs2_jbd2_inode_add_write(handle, inode, start_byte, length);
     if (ret < 0) {
         mlog_errno(ret);
         goto out;
     }
 
     ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
                       OCFS2_JOURNAL_ACCESS_WRITE);
     if (ret)
         mlog_errno(ret);
     ocfs2_update_inode_fsync_trans(handle, inode, 1);
 
 out:
     if (ret) {
         if (!IS_ERR(handle))
             ocfs2_commit_trans(osb, handle);
         handle = ERR_PTR(ret);
     }
     return handle;
 }
 
 /* Some parts of this taken from generic_cont_expand, which turned out
  * to be too fragile to do exactly what we need without us having to
  * worry about recursive locking in ->write_begin() and ->write_end(). */
 static int ocfs2_write_zero_page(struct inode *inode, u64 abs_from,
                  u64 abs_to, struct buffer_head *di_bh)
 {
     struct address_space *mapping = inode->i_mapping;
     struct page *page;
     unsigned long index = abs_from >> PAGE_SHIFT;
     handle_t *handle;
     int ret = 0;
     unsigned zero_from, zero_to, block_start, block_end;
     struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 
     BUG_ON(abs_from >= abs_to);
     BUG_ON(abs_to > (((u64)index + 1) << PAGE_SHIFT));
     BUG_ON(abs_from & (inode->i_blkbits - 1));
 
     handle = ocfs2_zero_start_ordered_transaction(inode, di_bh,
                               abs_from,
                               abs_to - abs_from);
     if (IS_ERR(handle)) {
         ret = PTR_ERR(handle);
         goto out;
     }
 
     page = find_or_create_page(mapping, index, GFP_NOFS);
     if (!page) {
         ret = -ENOMEM;
         mlog_errno(ret);
         goto out_commit_trans;
     }
 
     /* Get the offsets within the page that we want to zero */
     zero_from = abs_from & (PAGE_SIZE - 1);
     zero_to = abs_to & (PAGE_SIZE - 1);
     if (!zero_to)
         zero_to = PAGE_SIZE;
 
     trace_ocfs2_write_zero_page(
             (unsigned long long)OCFS2_I(inode)->ip_blkno,
             (unsigned long long)abs_from,
             (unsigned long long)abs_to,
             index, zero_from, zero_to);
 
     /* We know that zero_from is block aligned */
     for (block_start = zero_from; block_start < zero_to;
          block_start = block_end) {
         block_end = block_start + i_blocksize(inode);
 
         /*
          * block_start is block-aligned.  Bump it by one to force
          * __block_write_begin and block_commit_write to zero the
          * whole block.
          */
         ret = __block_write_begin(page, block_start + 1, 0,
                       ocfs2_get_block);
         if (ret < 0) {
             mlog_errno(ret);
             goto out_unlock;
         }
 
 
         /* must not update i_size! */
         ret = block_commit_write(page, block_start + 1,
                      block_start + 1);
         if (ret < 0)
             mlog_errno(ret);
         else
             ret = 0;
     }
 
     /*
      * fs-writeback will release the dirty pages without page lock
      * whose offset are over inode size, the release happens at
      * block_write_full_page().
      */
     i_size_write(inode, abs_to);
     inode->i_blocks = ocfs2_inode_sector_count(inode);
     di->i_size = cpu_to_le64((u64)i_size_read(inode));
     inode->i_mtime = inode->i_ctime = current_time(inode);
     di->i_mtime = di->i_ctime = cpu_to_le64(inode->i_mtime.tv_sec);
     di->i_ctime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
     di->i_mtime_nsec = di->i_ctime_nsec;
     if (handle) {
         ocfs2_journal_dirty(handle, di_bh);
         ocfs2_update_inode_fsync_trans(handle, inode, 1);
     }
 
 out_unlock:
     unlock_page(page);
     put_page(page);
 out_commit_trans:
     if (handle)
         ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle);
 out:
     return ret;
 }
 
 /*
  * Find the next range to zero.  We do this in terms of bytes because
  * that's what ocfs2_zero_extend() wants, and it is dealing with the
  * pagecache.  We may return multiple extents.
  *
  * zero_start and zero_end are ocfs2_zero_extend()s current idea of what
  * needs to be zeroed.  range_start and range_end return the next zeroing
  * range.  A subsequent call should pass the previous range_end as its
  * zero_start.  If range_end is 0, there's nothing to do.
  *
  * Unwritten extents are skipped over.  Refcounted extents are CoWd.
  */
 static int ocfs2_zero_extend_get_range(struct inode *inode,
                        struct buffer_head *di_bh,
                        u64 zero_start, u64 zero_end,
                        u64 *range_start, u64 *range_end)
 {
     int rc = 0, needs_cow = 0;
     u32 p_cpos, zero_clusters = 0;
     u32 zero_cpos =
         zero_start >> OCFS2_SB(inode->i_sb)->s_clustersize_bits;
     u32 last_cpos = ocfs2_clusters_for_bytes(inode->i_sb, zero_end);
     unsigned int num_clusters = 0;
     unsigned int ext_flags = 0;
 
     while (zero_cpos < last_cpos) {
         rc = ocfs2_get_clusters(inode, zero_cpos, &p_cpos,
                     &num_clusters, &ext_flags);
         if (rc) {
             mlog_errno(rc);
             goto out;
         }
 
         if (p_cpos && !(ext_flags & OCFS2_EXT_UNWRITTEN)) {
             zero_clusters = num_clusters;
             if (ext_flags & OCFS2_EXT_REFCOUNTED)
                 needs_cow = 1;
             break;
         }
 
         zero_cpos += num_clusters;
     }
     if (!zero_clusters) {
         *range_end = 0;
         goto out;
     }
 
     while ((zero_cpos + zero_clusters) < last_cpos) {
         rc = ocfs2_get_clusters(inode, zero_cpos + zero_clusters,
                     &p_cpos, &num_clusters,
                     &ext_flags);
         if (rc) {
             mlog_errno(rc);
             goto out;
         }
 
         if (!p_cpos || (ext_flags & OCFS2_EXT_UNWRITTEN))
             break;
         if (ext_flags & OCFS2_EXT_REFCOUNTED)
             needs_cow = 1;
         zero_clusters += num_clusters;
     }
     if ((zero_cpos + zero_clusters) > last_cpos)
         zero_clusters = last_cpos - zero_cpos;
 
     if (needs_cow) {
         rc = ocfs2_refcount_cow(inode, di_bh, zero_cpos,
                     zero_clusters, UINT_MAX);
         if (rc) {
             mlog_errno(rc);
             goto out;
         }
     }
 
     *range_start = ocfs2_clusters_to_bytes(inode->i_sb, zero_cpos);
     *range_end = ocfs2_clusters_to_bytes(inode->i_sb,
                          zero_cpos + zero_clusters);
 
 out:
     return rc;
 }
 
 /*
  * Zero one range returned from ocfs2_zero_extend_get_range().  The caller
  * has made sure that the entire range needs zeroing.
  */
 static int ocfs2_zero_extend_range(struct inode *inode, u64 range_start,
                    u64 range_end, struct buffer_head *di_bh)
 {
     int rc = 0;
     u64 next_pos;
     u64 zero_pos = range_start;
 
     trace_ocfs2_zero_extend_range(
             (unsigned long long)OCFS2_I(inode)->ip_blkno,
             (unsigned long long)range_start,
             (unsigned long long)range_end);
     BUG_ON(range_start >= range_end);
 
     while (zero_pos < range_end) {
         next_pos = (zero_pos & PAGE_MASK) + PAGE_SIZE;
         if (next_pos > range_end)
             next_pos = range_end;
         rc = ocfs2_write_zero_page(inode, zero_pos, next_pos, di_bh);
         if (rc < 0) {
             mlog_errno(rc);
             break;
         }
         zero_pos = next_pos;
 
         /*
          * Very large extends have the potential to lock up
          * the cpu for extended periods of time.
          */
         cond_resched();
     }
 
     return rc;
 }
 
 int ocfs2_zero_extend(struct inode *inode, struct buffer_head *di_bh,
               loff_t zero_to_size)
 {
     int ret = 0;
     u64 zero_start, range_start = 0, range_end = 0;
     struct super_block *sb = inode->i_sb;
 
     zero_start = ocfs2_align_bytes_to_blocks(sb, i_size_read(inode));
     trace_ocfs2_zero_extend((unsigned long long)OCFS2_I(inode)->ip_blkno,
                 (unsigned long long)zero_start,
                 (unsigned long long)i_size_read(inode));
     while (zero_start < zero_to_size) {
         ret = ocfs2_zero_extend_get_range(inode, di_bh, zero_start,
                           zero_to_size,
                           &range_start,
                           &range_end);
         if (ret) {
             mlog_errno(ret);
             break;
         }
         if (!range_end)
             break;
         /* Trim the ends */
         if (range_start < zero_start)
             range_start = zero_start;
         if (range_end > zero_to_size)
             range_end = zero_to_size;
 
         ret = ocfs2_zero_extend_range(inode, range_start,
                           range_end, di_bh);
         if (ret) {
             mlog_errno(ret);
             break;
         }
         zero_start = range_end;
     }
 
     return ret;
 }
 
 int ocfs2_extend_no_holes(struct inode *inode, struct buffer_head *di_bh,
               u64 new_i_size, u64 zero_to)
 {
     int ret;
     u32 clusters_to_add;
     struct ocfs2_inode_info *oi = OCFS2_I(inode);
 
     /*
      * Only quota files call this without a bh, and they can't be
      * refcounted.
      */
     BUG_ON(!di_bh && ocfs2_is_refcount_inode(inode));
     BUG_ON(!di_bh && !(oi->ip_flags & OCFS2_INODE_SYSTEM_FILE));
 
     clusters_to_add = ocfs2_clusters_for_bytes(inode->i_sb, new_i_size);
     if (clusters_to_add < oi->ip_clusters)
         clusters_to_add = 0;
     else
         clusters_to_add -= oi->ip_clusters;
 
     if (clusters_to_add) {
         ret = ocfs2_extend_allocation(inode, oi->ip_clusters,
                           clusters_to_add, 0);
         if (ret) {
             mlog_errno(ret);
             goto out;
         }
     }
 
     /*
      * Call this even if we don't add any clusters to the tree. We
      * still need to zero the area between the old i_size and the
      * new i_size.
      */
     ret = ocfs2_zero_extend(inode, di_bh, zero_to);
     if (ret < 0)
         mlog_errno(ret);
 
 out:
     return ret;
 }
 
 static int ocfs2_extend_file(struct inode *inode,
                  struct buffer_head *di_bh,
                  u64 new_i_size)
 {
     int ret = 0;
     struct ocfs2_inode_info *oi = OCFS2_I(inode);
 
     BUG_ON(!di_bh);
 
     /* setattr sometimes calls us like this. */
     if (new_i_size == 0)
         goto out;
 
     if (i_size_read(inode) == new_i_size)
         goto out;
     BUG_ON(new_i_size < i_size_read(inode));
 
     /*
      * The alloc sem blocks people in read/write from reading our
      * allocation until we're done changing it. We depend on
      * i_rwsem to block other extend/truncate calls while we're
      * here.  We even have to hold it for sparse files because there
      * might be some tail zeroing.
      */
     down_write(&oi->ip_alloc_sem);
 
     if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
         /*
          * We can optimize small extends by keeping the inodes
          * inline data.
          */
         if (ocfs2_size_fits_inline_data(di_bh, new_i_size)) {
             up_write(&oi->ip_alloc_sem);
             goto out_update_size;
         }
 
         ret = ocfs2_convert_inline_data_to_extents(inode, di_bh);
         if (ret) {
             up_write(&oi->ip_alloc_sem);
             mlog_errno(ret);
             goto out;
         }
     }
 
     if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)))
         ret = ocfs2_zero_extend(inode, di_bh, new_i_size);
     else
         ret = ocfs2_extend_no_holes(inode, di_bh, new_i_size,
                         new_i_size);
 
     up_write(&oi->ip_alloc_sem);
 
     if (ret < 0) {
         mlog_errno(ret);
         goto out;
     }
 
 out_update_size:
     ret = ocfs2_simple_size_update(inode, di_bh, new_i_size);
     if (ret < 0)
         mlog_errno(ret);
 
 out:
     return ret;
 }
 
 int ocfs2_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
           struct iattr *attr)
 {
     int status = 0, size_change;
     int inode_locked = 0;
     struct inode *inode = d_inode(dentry);
     struct super_block *sb = inode->i_sb;
     struct ocfs2_super *osb = OCFS2_SB(sb);
     struct buffer_head *bh = NULL;
     handle_t *handle = NULL;
     struct dquot *transfer_to[MAXQUOTAS] = { };
     int qtype;
     int had_lock;
     struct ocfs2_lock_holder oh;
 
     trace_ocfs2_setattr(inode, dentry,
                 (unsigned long long)OCFS2_I(inode)->ip_blkno,
                 dentry->d_name.len, dentry->d_name.name,
                 attr->ia_valid, attr->ia_mode,
                 from_kuid(&init_user_ns, attr->ia_uid),
                 from_kgid(&init_user_ns, attr->ia_gid));
 
     /* ensuring we don't even attempt to truncate a symlink */
     if (S_ISLNK(inode->i_mode))
         attr->ia_valid &= ~ATTR_SIZE;
 
 #define OCFS2_VALID_ATTRS (ATTR_ATIME | ATTR_MTIME | ATTR_CTIME | ATTR_SIZE \
                | ATTR_GID | ATTR_UID | ATTR_MODE)
     if (!(attr->ia_valid & OCFS2_VALID_ATTRS))
         return 0;
 
     status = setattr_prepare(&init_user_ns, dentry, attr);
     if (status)
         return status;
 
     if (is_quota_modification(mnt_userns, inode, attr)) {
         status = dquot_initialize(inode);
         if (status)
             return status;
     }
     size_change = S_ISREG(inode->i_mode) && attr->ia_valid & ATTR_SIZE;
     if (size_change) {
         /*
          * Here we should wait dio to finish before inode lock
          * to avoid a deadlock between ocfs2_setattr() and
          * ocfs2_dio_end_io_write()
          */
         inode_dio_wait(inode);
 
         status = ocfs2_rw_lock(inode, 1);
         if (status < 0) {
             mlog_errno(status);
             goto bail;
         }
     }
 
     had_lock = ocfs2_inode_lock_tracker(inode, &bh, 1, &oh);
     if (had_lock < 0) {
         status = had_lock;
         goto bail_unlock_rw;
     } else if (had_lock) {
         /*
          * As far as we know, ocfs2_setattr() could only be the first
          * VFS entry point in the call chain of recursive cluster
          * locking issue.
          *
          * For instance:
          * chmod_common()
          *  notify_change()
          *   ocfs2_setattr()
          *    posix_acl_chmod()
          *     ocfs2_iop_get_acl()
          *
          * But, we're not 100% sure if it's always true, because the
          * ordering of the VFS entry points in the call chain is out
          * of our control. So, we'd better dump the stack here to
          * catch the other cases of recursive locking.
          */
         mlog(ML_ERROR, "Another case of recursive locking:\n");
         dump_stack();
     }
     inode_locked = 1;
 
     if (size_change) {
         status = inode_newsize_ok(inode, attr->ia_size);
         if (status)
             goto bail_unlock;
 
         if (i_size_read(inode) >= attr->ia_size) {
             if (ocfs2_should_order_data(inode)) {
                 status = ocfs2_begin_ordered_truncate(inode,
                                       attr->ia_size);
                 if (status)
                     goto bail_unlock;
             }
             status = ocfs2_truncate_file(inode, bh, attr->ia_size);
         } else
             status = ocfs2_extend_file(inode, bh, attr->ia_size);
         if (status < 0) {
             if (status != -ENOSPC)
                 mlog_errno(status);
             status = -ENOSPC;
             goto bail_unlock;
         }
     }
 
     if ((attr->ia_valid & ATTR_UID && !uid_eq(attr->ia_uid, inode->i_uid)) ||
         (attr->ia_valid & ATTR_GID && !gid_eq(attr->ia_gid, inode->i_gid))) {
         /*
          * Gather pointers to quota structures so that allocation /
          * freeing of quota structures happens here and not inside
          * dquot_transfer() where we have problems with lock ordering
          */
         if (attr->ia_valid & ATTR_UID && !uid_eq(attr->ia_uid, inode->i_uid)
             && OCFS2_HAS_RO_COMPAT_FEATURE(sb,
             OCFS2_FEATURE_RO_COMPAT_USRQUOTA)) {
             transfer_to[USRQUOTA] = dqget(sb, make_kqid_uid(attr->ia_uid));
             if (IS_ERR(transfer_to[USRQUOTA])) {
                 status = PTR_ERR(transfer_to[USRQUOTA]);
                 transfer_to[USRQUOTA] = NULL;
                 goto bail_unlock;
             }
         }
         if (attr->ia_valid & ATTR_GID && !gid_eq(attr->ia_gid, inode->i_gid)
             && OCFS2_HAS_RO_COMPAT_FEATURE(sb,
             OCFS2_FEATURE_RO_COMPAT_GRPQUOTA)) {
             transfer_to[GRPQUOTA] = dqget(sb, make_kqid_gid(attr->ia_gid));
             if (IS_ERR(transfer_to[GRPQUOTA])) {
                 status = PTR_ERR(transfer_to[GRPQUOTA]);
                 transfer_to[GRPQUOTA] = NULL;
                 goto bail_unlock;
             }
         }
         down_write(&OCFS2_I(inode)->ip_alloc_sem);
         handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS +
                        2 * ocfs2_quota_trans_credits(sb));
         if (IS_ERR(handle)) {
             status = PTR_ERR(handle);
             mlog_errno(status);
             goto bail_unlock_alloc;
         }
         status = __dquot_transfer(inode, transfer_to);
         if (status < 0)
             goto bail_commit;
     } else {
         down_write(&OCFS2_I(inode)->ip_alloc_sem);
         handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
         if (IS_ERR(handle)) {
             status = PTR_ERR(handle);
             mlog_errno(status);
             goto bail_unlock_alloc;
         }
     }
 
     setattr_copy(&init_user_ns, inode, attr);
     mark_inode_dirty(inode);
 
     status = ocfs2_mark_inode_dirty(handle, inode, bh);
     if (status < 0)
         mlog_errno(status);
 
 bail_commit:
     ocfs2_commit_trans(osb, handle);
 bail_unlock_alloc:
     up_write(&OCFS2_I(inode)->ip_alloc_sem);
 bail_unlock:
     if (status && inode_locked) {
         ocfs2_inode_unlock_tracker(inode, 1, &oh, had_lock);
         inode_locked = 0;
     }
 bail_unlock_rw:
     if (size_change)
         ocfs2_rw_unlock(inode, 1);
 bail:
 
     /* Release quota pointers in case we acquired them */
     for (qtype = 0; qtype < OCFS2_MAXQUOTAS; qtype++)
         dqput(transfer_to[qtype]);
 
     if (!status && attr->ia_valid & ATTR_MODE) {
         status = ocfs2_acl_chmod(inode, bh);
         if (status < 0)
             mlog_errno(status);
     }
     if (inode_locked)
         ocfs2_inode_unlock_tracker(inode, 1, &oh, had_lock);
 
     brelse(bh);
     return status;
 }
 
 int ocfs2_getattr(struct user_namespace *mnt_userns, const struct path *path,
           struct kstat *stat, u32 request_mask, unsigned int flags)
 {
     struct inode *inode = d_inode(path->dentry);
     struct super_block *sb = path->dentry->d_sb;
     struct ocfs2_super *osb = sb->s_fs_info;
     int err;
 
     err = ocfs2_inode_revalidate(path->dentry);
     if (err) {
         if (err != -ENOENT)
             mlog_errno(err);
         goto bail;
     }
 
     generic_fillattr(&init_user_ns, inode, stat);
     /*
      * If there is inline data in the inode, the inode will normally not
      * have data blocks allocated (it may have an external xattr block).
      * Report at least one sector for such files, so tools like tar, rsync,
      * others don't incorrectly think the file is completely sparse.
      */
     if (unlikely(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL))
         stat->blocks += (stat->size + 511)>>9;
 
     /* We set the blksize from the cluster size for performance */
     stat->blksize = osb->s_clustersize;
 
 bail:
     return err;
 }
 
 int ocfs2_permission(struct user_namespace *mnt_userns, struct inode *inode,
              int mask)
 {
     int ret, had_lock;
     struct ocfs2_lock_holder oh;
 
     if (mask & MAY_NOT_BLOCK)
         return -ECHILD;
 
     had_lock = ocfs2_inode_lock_tracker(inode, NULL, 0, &oh);
     if (had_lock < 0) {
         ret = had_lock;
         goto out;
     } else if (had_lock) {
         /* See comments in ocfs2_setattr() for details.
          * The call chain of this case could be:
          * do_sys_open()
          *  may_open()
          *   inode_permission()
          *    ocfs2_permission()
          *     ocfs2_iop_get_acl()
          */
         mlog(ML_ERROR, "Another case of recursive locking:\n");
         dump_stack();
     }
 
     ret = generic_permission(&init_user_ns, inode, mask);
 
     ocfs2_inode_unlock_tracker(inode, 0, &oh, had_lock);
 out:
     return ret;
 }
 
 static int __ocfs2_write_remove_suid(struct inode *inode,
                      struct buffer_head *bh)
 {
     int ret;
     handle_t *handle;
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     struct ocfs2_dinode *di;
 
     trace_ocfs2_write_remove_suid(
             (unsigned long long)OCFS2_I(inode)->ip_blkno,
             inode->i_mode);
 
     handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
     if (IS_ERR(handle)) {
         ret = PTR_ERR(handle);
         mlog_errno(ret);
         goto out;
     }
 
     ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), bh,
                       OCFS2_JOURNAL_ACCESS_WRITE);
     if (ret < 0) {
         mlog_errno(ret);
         goto out_trans;
     }
 
     inode->i_mode &= ~S_ISUID;
     if ((inode->i_mode & S_ISGID) && (inode->i_mode & S_IXGRP))
         inode->i_mode &= ~S_ISGID;
 
     di = (struct ocfs2_dinode *) bh->b_data;
     di->i_mode = cpu_to_le16(inode->i_mode);
     ocfs2_update_inode_fsync_trans(handle, inode, 0);
 
     ocfs2_journal_dirty(handle, bh);
 
 out_trans:
     ocfs2_commit_trans(osb, handle);
 out:
     return ret;
 }
 
 static int ocfs2_write_remove_suid(struct inode *inode)
 {
     int ret;
     struct buffer_head *bh = NULL;
 
     ret = ocfs2_read_inode_block(inode, &bh);
     if (ret < 0) {
         mlog_errno(ret);
         goto out;
     }
 
     ret =  __ocfs2_write_remove_suid(inode, bh);
 out:
     brelse(bh);
     return ret;
 }
 
 /*
  * Allocate enough extents to cover the region starting at byte offset
  * start for len bytes. Existing extents are skipped, any extents
  * added are marked as "unwritten".
  */
 static int ocfs2_allocate_unwritten_extents(struct inode *inode,
                         u64 start, u64 len)
 {
     int ret;
     u32 cpos, phys_cpos, clusters, alloc_size;
     u64 end = start + len;
     struct buffer_head *di_bh = NULL;
 
     if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
         ret = ocfs2_read_inode_block(inode, &di_bh);
         if (ret) {
             mlog_errno(ret);
             goto out;
         }
 
         /*
          * Nothing to do if the requested reservation range
          * fits within the inode.
          */
         if (ocfs2_size_fits_inline_data(di_bh, end))
             goto out;
 
         ret = ocfs2_convert_inline_data_to_extents(inode, di_bh);
         if (ret) {
             mlog_errno(ret);
             goto out;
         }
     }
 
     /*
      * We consider both start and len to be inclusive.
      */
     cpos = start >> OCFS2_SB(inode->i_sb)->s_clustersize_bits;
     clusters = ocfs2_clusters_for_bytes(inode->i_sb, start + len);
     clusters -= cpos;
 
     while (clusters) {
         ret = ocfs2_get_clusters(inode, cpos, &phys_cpos,
                      &alloc_size, NULL);
         if (ret) {
             mlog_errno(ret);
             goto out;
         }
 
         /*
          * Hole or existing extent len can be arbitrary, so
          * cap it to our own allocation request.
          */
         if (alloc_size > clusters)
             alloc_size = clusters;
 
         if (phys_cpos) {
             /*
              * We already have an allocation at this
              * region so we can safely skip it.
              */
             goto next;
         }
 
         ret = ocfs2_extend_allocation(inode, cpos, alloc_size, 1);
         if (ret) {
             if (ret != -ENOSPC)
                 mlog_errno(ret);
             goto out;
         }
 
 next:
         cpos += alloc_size;
         clusters -= alloc_size;
     }
 
     ret = 0;
 out:
 
     brelse(di_bh);
     return ret;
 }
 
 /*
  * Truncate a byte range, avoiding pages within partial clusters. This
  * preserves those pages for the zeroing code to write to.
  */
 static void ocfs2_truncate_cluster_pages(struct inode *inode, u64 byte_start,
                      u64 byte_len)
 {
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     loff_t start, end;
     struct address_space *mapping = inode->i_mapping;
 
     start = (loff_t)ocfs2_align_bytes_to_clusters(inode->i_sb, byte_start);
     end = byte_start + byte_len;
     end = end & ~(osb->s_clustersize - 1);
 
     if (start < end) {
         unmap_mapping_range(mapping, start, end - start, 0);
         truncate_inode_pages_range(mapping, start, end - 1);
     }
 }
 
 /*
  * zero out partial blocks of one cluster.
  *
  * start: file offset where zero starts, will be made upper block aligned.
  * len: it will be trimmed to the end of current cluster if "start + len"
  *      is bigger than it.
  */
 static int ocfs2_zeroout_partial_cluster(struct inode *inode,
                     u64 start, u64 len)
 {
     int ret;
     u64 start_block, end_block, nr_blocks;
     u64 p_block, offset;
     u32 cluster, p_cluster, nr_clusters;
     struct super_block *sb = inode->i_sb;
     u64 end = ocfs2_align_bytes_to_clusters(sb, start);
 
     if (start + len < end)
         end = start + len;
 
     start_block = ocfs2_blocks_for_bytes(sb, start);
     end_block = ocfs2_blocks_for_bytes(sb, end);
     nr_blocks = end_block - start_block;
     if (!nr_blocks)
         return 0;
 
     cluster = ocfs2_bytes_to_clusters(sb, start);
     ret = ocfs2_get_clusters(inode, cluster, &p_cluster,
                 &nr_clusters, NULL);
     if (ret)
         return ret;
     if (!p_cluster)
         return 0;
 
     offset = start_block - ocfs2_clusters_to_blocks(sb, cluster);
     p_block = ocfs2_clusters_to_blocks(sb, p_cluster) + offset;
     return sb_issue_zeroout(sb, p_block, nr_blocks, GFP_NOFS);
 }
 
 static int ocfs2_zero_partial_clusters(struct inode *inode,
                        u64 start, u64 len)
 {
     int ret = 0;
     u64 tmpend = 0;
     u64 end = start + len;
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     unsigned int csize = osb->s_clustersize;
     handle_t *handle;
     loff_t isize = i_size_read(inode);
 
     /*
      * The "start" and "end" values are NOT necessarily part of
      * the range whose allocation is being deleted. Rather, this
      * is what the user passed in with the request. We must zero
      * partial clusters here. There's no need to worry about
      * physical allocation - the zeroing code knows to skip holes.
      */
     trace_ocfs2_zero_partial_clusters(
         (unsigned long long)OCFS2_I(inode)->ip_blkno,
         (unsigned long long)start, (unsigned long long)end);
 
     /*
      * If both edges are on a cluster boundary then there's no
      * zeroing required as the region is part of the allocation to
      * be truncated.
      */
     if ((start & (csize - 1)) == 0 && (end & (csize - 1)) == 0)
         goto out;
 
     /* No page cache for EOF blocks, issue zero out to disk. */
     if (end > isize) {
         /*
          * zeroout eof blocks in last cluster starting from
          * "isize" even "start" > "isize" because it is
          * complicated to zeroout just at "start" as "start"
          * may be not aligned with block size, buffer write
          * would be required to do that, but out of eof buffer
          * write is not supported.
          */
         ret = ocfs2_zeroout_partial_cluster(inode, isize,
                     end - isize);
         if (ret) {
             mlog_errno(ret);
             goto out;
         }
         if (start >= isize)
             goto out;
         end = isize;
     }
     handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
     if (IS_ERR(handle)) {
         ret = PTR_ERR(handle);
         mlog_errno(ret);
         goto out;
     }
 
     /*
      * If start is on a cluster boundary and end is somewhere in another
      * cluster, we have not COWed the cluster starting at start, unless
      * end is also within the same cluster. So, in this case, we skip this
      * first call to ocfs2_zero_range_for_truncate() truncate and move on
      * to the next one.
      */
     if ((start & (csize - 1)) != 0) {
         /*
          * We want to get the byte offset of the end of the 1st
          * cluster.
          */
         tmpend = (u64)osb->s_clustersize +
             (start & ~(osb->s_clustersize - 1));
         if (tmpend > end)
             tmpend = end;
 
         trace_ocfs2_zero_partial_clusters_range1(
             (unsigned long long)start,
             (unsigned long long)tmpend);
 
         ret = ocfs2_zero_range_for_truncate(inode, handle, start,
                             tmpend);
         if (ret)
             mlog_errno(ret);
     }
 
     if (tmpend < end) {
         /*
          * This may make start and end equal, but the zeroing
          * code will skip any work in that case so there's no
          * need to catch it up here.
          */
         start = end & ~(osb->s_clustersize - 1);
 
         trace_ocfs2_zero_partial_clusters_range2(
             (unsigned long long)start, (unsigned long long)end);
 
         ret = ocfs2_zero_range_for_truncate(inode, handle, start, end);
         if (ret)
             mlog_errno(ret);
     }
     ocfs2_update_inode_fsync_trans(handle, inode, 1);
 
     ocfs2_commit_trans(osb, handle);
 out:
     return ret;
 }
 
 static int ocfs2_find_rec(struct ocfs2_extent_list *el, u32 pos)
 {
     int i;
     struct ocfs2_extent_rec *rec = NULL;
 
     for (i = le16_to_cpu(el->l_next_free_rec) - 1; i >= 0; i--) {
 
         rec = &el->l_recs[i];
 
         if (le32_to_cpu(rec->e_cpos) < pos)
             break;
     }
 
     return i;
 }
 
 /*
  * Helper to calculate the punching pos and length in one run, we handle the
  * following three cases in order:
  *
  * - remove the entire record
  * - remove a partial record
  * - no record needs to be removed (hole-punching completed)
 */
 static void ocfs2_calc_trunc_pos(struct inode *inode,
                  struct ocfs2_extent_list *el,
                  struct ocfs2_extent_rec *rec,
                  u32 trunc_start, u32 *trunc_cpos,
                  u32 *trunc_len, u32 *trunc_end,
                  u64 *blkno, int *done)
 {
     int ret = 0;
     u32 coff, range;
 
     range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
 
     if (le32_to_cpu(rec->e_cpos) >= trunc_start) {
         /*
          * remove an entire extent record.
          */
         *trunc_cpos = le32_to_cpu(rec->e_cpos);
         /*
          * Skip holes if any.
          */
         if (range < *trunc_end)
             *trunc_end = range;
         *trunc_len = *trunc_end - le32_to_cpu(rec->e_cpos);
         *blkno = le64_to_cpu(rec->e_blkno);
         *trunc_end = le32_to_cpu(rec->e_cpos);
     } else if (range > trunc_start) {
         /*
          * remove a partial extent record, which means we're
          * removing the last extent record.
          */
         *trunc_cpos = trunc_start;
         /*
          * skip hole if any.
          */
         if (range < *trunc_end)
             *trunc_end = range;
         *trunc_len = *trunc_end - trunc_start;
         coff = trunc_start - le32_to_cpu(rec->e_cpos);
         *blkno = le64_to_cpu(rec->e_blkno) +
                 ocfs2_clusters_to_blocks(inode->i_sb, coff);
         *trunc_end = trunc_start;
     } else {
         /*
          * It may have two following possibilities:
          *
          * - last record has been removed
          * - trunc_start was within a hole
          *
          * both two cases mean the completion of hole punching.
          */
         ret = 1;
     }
 
     *done = ret;
 }
 
 int ocfs2_remove_inode_range(struct inode *inode,
                  struct buffer_head *di_bh, u64 byte_start,
                  u64 byte_len)
 {
     int ret = 0, flags = 0, done = 0, i;
     u32 trunc_start, trunc_len, trunc_end, trunc_cpos, phys_cpos;
     u32 cluster_in_el;
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     struct ocfs2_cached_dealloc_ctxt dealloc;
     struct address_space *mapping = inode->i_mapping;
     struct ocfs2_extent_tree et;
     struct ocfs2_path *path = NULL;
     struct ocfs2_extent_list *el = NULL;
     struct ocfs2_extent_rec *rec = NULL;
     struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
     u64 blkno, refcount_loc = le64_to_cpu(di->i_refcount_loc);
 
     ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh);
     ocfs2_init_dealloc_ctxt(&dealloc);
 
     trace_ocfs2_remove_inode_range(
             (unsigned long long)OCFS2_I(inode)->ip_blkno,
             (unsigned long long)byte_start,
             (unsigned long long)byte_len);
 
     if (byte_len == 0)
         return 0;
 
     if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
         ret = ocfs2_truncate_inline(inode, di_bh, byte_start,
                         byte_start + byte_len, 0);
         if (ret) {
             mlog_errno(ret);
             goto out;
         }
         /*
          * There's no need to get fancy with the page cache
          * truncate of an inline-data inode. We're talking
          * about less than a page here, which will be cached
          * in the dinode buffer anyway.
          */
         unmap_mapping_range(mapping, 0, 0, 0);
         truncate_inode_pages(mapping, 0);
         goto out;
     }
 
     /*
      * For reflinks, we may need to CoW 2 clusters which might be
      * partially zero'd later, if hole's start and end offset were
      * within one cluster(means is not exactly aligned to clustersize).
      */
 
     if (ocfs2_is_refcount_inode(inode)) {
         ret = ocfs2_cow_file_pos(inode, di_bh, byte_start);
         if (ret) {
             mlog_errno(ret);
             goto out;
         }
 
         ret = ocfs2_cow_file_pos(inode, di_bh, byte_start + byte_len);
         if (ret) {
             mlog_errno(ret);
             goto out;
         }
     }
 
     trunc_start = ocfs2_clusters_for_bytes(osb->sb, byte_start);
     trunc_end = (byte_start + byte_len) >> osb->s_clustersize_bits;
     cluster_in_el = trunc_end;
 
     ret = ocfs2_zero_partial_clusters(inode, byte_start, byte_len);
     if (ret) {
         mlog_errno(ret);
         goto out;
     }
 
     path = ocfs2_new_path_from_et(&et);
     if (!path) {
         ret = -ENOMEM;
         mlog_errno(ret);
         goto out;
     }
 
     while (trunc_end > trunc_start) {
 
         ret = ocfs2_find_path(INODE_CACHE(inode), path,
                       cluster_in_el);
         if (ret) {
             mlog_errno(ret);
             goto out;
         }
 
         el = path_leaf_el(path);
 
         i = ocfs2_find_rec(el, trunc_end);
         /*
          * Need to go to previous extent block.
          */
         if (i < 0) {
             if (path->p_tree_depth == 0)
                 break;
 
             ret = ocfs2_find_cpos_for_left_leaf(inode->i_sb,
                                 path,
                                 &cluster_in_el);
             if (ret) {
                 mlog_errno(ret);
                 goto out;
             }
 
             /*
              * We've reached the leftmost extent block,
              * it's safe to leave.
              */
             if (cluster_in_el == 0)
                 break;
 
             /*
              * The 'pos' searched for previous extent block is
              * always one cluster less than actual trunc_end.
              */
             trunc_end = cluster_in_el + 1;
 
             ocfs2_reinit_path(path, 1);
 
             continue;
 
         } else
             rec = &el->l_recs[i];
 
         ocfs2_calc_trunc_pos(inode, el, rec, trunc_start, &trunc_cpos,
                      &trunc_len, &trunc_end, &blkno, &done);
         if (done)
             break;
 
         flags = rec->e_flags;
         phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
 
         ret = ocfs2_remove_btree_range(inode, &et, trunc_cpos,
                            phys_cpos, trunc_len, flags,
                            &dealloc, refcount_loc, false);
         if (ret < 0) {
             mlog_errno(ret);
             goto out;
         }
 
         cluster_in_el = trunc_end;
 
         ocfs2_reinit_path(path, 1);
     }
 
     ocfs2_truncate_cluster_pages(inode, byte_start, byte_len);
 
 out:
     ocfs2_free_path(path);
     ocfs2_schedule_truncate_log_flush(osb, 1);
     ocfs2_run_deallocs(osb, &dealloc);
 
     return ret;
 }
 
 /*
  * Parts of this function taken from xfs_change_file_space()
  */
 static int __ocfs2_change_file_space(struct file *file, struct inode *inode,
                      loff_t f_pos, unsigned int cmd,
                      struct ocfs2_space_resv *sr,
                      int change_size)
 {
     int ret;
     s64 llen;
     loff_t size, orig_isize;
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     struct buffer_head *di_bh = NULL;
     handle_t *handle;
     unsigned long long max_off = inode->i_sb->s_maxbytes;
 
     if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
         return -EROFS;
 
     inode_lock(inode);
 
     /*
      * This prevents concurrent writes on other nodes
      */
     ret = ocfs2_rw_lock(inode, 1);
     if (ret) {
         mlog_errno(ret);
         goto out;
     }
 
     ret = ocfs2_inode_lock(inode, &di_bh, 1);
     if (ret) {
         mlog_errno(ret);
         goto out_rw_unlock;
     }
 
     if (inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
         ret = -EPERM;
         goto out_inode_unlock;
     }
 
     switch (sr->l_whence) {
     case 0: /*SEEK_SET*/
         break;
     case 1: /*SEEK_CUR*/
         sr->l_start += f_pos;
         break;
     case 2: /*SEEK_END*/
         sr->l_start += i_size_read(inode);
         break;
     default:
         ret = -EINVAL;
         goto out_inode_unlock;
     }
     sr->l_whence = 0;
 
     llen = sr->l_len > 0 ? sr->l_len - 1 : sr->l_len;
 
     if (sr->l_start < 0
         || sr->l_start > max_off
         || (sr->l_start + llen) < 0
         || (sr->l_start + llen) > max_off) {
         ret = -EINVAL;
         goto out_inode_unlock;
     }
     size = sr->l_start + sr->l_len;
 
     if (cmd == OCFS2_IOC_RESVSP || cmd == OCFS2_IOC_RESVSP64 ||
         cmd == OCFS2_IOC_UNRESVSP || cmd == OCFS2_IOC_UNRESVSP64) {
         if (sr->l_len <= 0) {
             ret = -EINVAL;
             goto out_inode_unlock;
         }
     }
 
     if (file && should_remove_suid(file->f_path.dentry)) {
         ret = __ocfs2_write_remove_suid(inode, di_bh);
         if (ret) {
             mlog_errno(ret);
             goto out_inode_unlock;
         }
     }
 
     down_write(&OCFS2_I(inode)->ip_alloc_sem);
     switch (cmd) {
     case OCFS2_IOC_RESVSP:
     case OCFS2_IOC_RESVSP64:
         /*
          * This takes unsigned offsets, but the signed ones we
          * pass have been checked against overflow above.
          */
         ret = ocfs2_allocate_unwritten_extents(inode, sr->l_start,
                                sr->l_len);
         break;
     case OCFS2_IOC_UNRESVSP:
     case OCFS2_IOC_UNRESVSP64:
         ret = ocfs2_remove_inode_range(inode, di_bh, sr->l_start,
                            sr->l_len);
         break;
     default:
         ret = -EINVAL;
     }
 
     orig_isize = i_size_read(inode);
     /* zeroout eof blocks in the cluster. */
     if (!ret && change_size && orig_isize < size) {
         ret = ocfs2_zeroout_partial_cluster(inode, orig_isize,
                     size - orig_isize);
         if (!ret)
             i_size_write(inode, size);
     }
     up_write(&OCFS2_I(inode)->ip_alloc_sem);
     if (ret) {
         mlog_errno(ret);
         goto out_inode_unlock;
     }
 
     /*
      * We update c/mtime for these changes
      */
     handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
     if (IS_ERR(handle)) {
         ret = PTR_ERR(handle);
         mlog_errno(ret);
         goto out_inode_unlock;
     }
 
     inode->i_ctime = inode->i_mtime = current_time(inode);
     ret = ocfs2_mark_inode_dirty(handle, inode, di_bh);
     if (ret < 0)
         mlog_errno(ret);
 
     if (file && (file->f_flags & O_SYNC))
         handle->h_sync = 1;
 
     ocfs2_commit_trans(osb, handle);
 
 out_inode_unlock:
     brelse(di_bh);
     ocfs2_inode_unlock(inode, 1);
 out_rw_unlock:
     ocfs2_rw_unlock(inode, 1);
 
 out:
     inode_unlock(inode);
     return ret;
 }
 
 int ocfs2_change_file_space(struct file *file, unsigned int cmd,
                 struct ocfs2_space_resv *sr)
 {
     struct inode *inode = file_inode(file);
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     int ret;
 
     if ((cmd == OCFS2_IOC_RESVSP || cmd == OCFS2_IOC_RESVSP64) &&
         !ocfs2_writes_unwritten_extents(osb))
         return -ENOTTY;
     else if ((cmd == OCFS2_IOC_UNRESVSP || cmd == OCFS2_IOC_UNRESVSP64) &&
          !ocfs2_sparse_alloc(osb))
         return -ENOTTY;
 
     if (!S_ISREG(inode->i_mode))
         return -EINVAL;
 
     if (!(file->f_mode & FMODE_WRITE))
         return -EBADF;
 
     ret = mnt_want_write_file(file);
     if (ret)
         return ret;
     ret = __ocfs2_change_file_space(file, inode, file->f_pos, cmd, sr, 0);
     mnt_drop_write_file(file);
     return ret;
 }
 
 static long ocfs2_fallocate(struct file *file, int mode, loff_t offset,
                 loff_t len)
 {
     struct inode *inode = file_inode(file);
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     struct ocfs2_space_resv sr;
     int change_size = 1;
     int cmd = OCFS2_IOC_RESVSP64;
 
     if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
         return -EOPNOTSUPP;
     if (!ocfs2_writes_unwritten_extents(osb))
         return -EOPNOTSUPP;
 
     if (mode & FALLOC_FL_KEEP_SIZE)
         change_size = 0;
 
     if (mode & FALLOC_FL_PUNCH_HOLE)
         cmd = OCFS2_IOC_UNRESVSP64;
 
     sr.l_whence = 0;
     sr.l_start = (s64)offset;
     sr.l_len = (s64)len;
 
     return __ocfs2_change_file_space(NULL, inode, offset, cmd, &sr,
                      change_size);
 }
 
 int ocfs2_check_range_for_refcount(struct inode *inode, loff_t pos,
                    size_t count)
 {
     int ret = 0;
     unsigned int extent_flags;
     u32 cpos, clusters, extent_len, phys_cpos;
     struct super_block *sb = inode->i_sb;
 
     if (!ocfs2_refcount_tree(OCFS2_SB(inode->i_sb)) ||
         !ocfs2_is_refcount_inode(inode) ||
         OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
         return 0;
 
     cpos = pos >> OCFS2_SB(sb)->s_clustersize_bits;
     clusters = ocfs2_clusters_for_bytes(sb, pos + count) - cpos;
 
     while (clusters) {
         ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &extent_len,
                      &extent_flags);
         if (ret < 0) {
             mlog_errno(ret);
             goto out;
         }
 
         if (phys_cpos && (extent_flags & OCFS2_EXT_REFCOUNTED)) {
             ret = 1;
             break;
         }
 
         if (extent_len > clusters)
             extent_len = clusters;
 
         clusters -= extent_len;
         cpos += extent_len;
     }
 out:
     return ret;
 }
 
 static int ocfs2_is_io_unaligned(struct inode *inode, size_t count, loff_t pos)
 {
     int blockmask = inode->i_sb->s_blocksize - 1;
     loff_t final_size = pos + count;
 
     if ((pos & blockmask) || (final_size & blockmask))
         return 1;
     return 0;
 }
 
 static int ocfs2_inode_lock_for_extent_tree(struct inode *inode,
                         struct buffer_head **di_bh,
                         int meta_level,
                         int write_sem,
                         int wait)
 {
     int ret = 0;
 
     if (wait)
         ret = ocfs2_inode_lock(inode, di_bh, meta_level);
     else
         ret = ocfs2_try_inode_lock(inode, di_bh, meta_level);
     if (ret < 0)
         goto out;
 
     if (wait) {
         if (write_sem)
             down_write(&OCFS2_I(inode)->ip_alloc_sem);
         else
             down_read(&OCFS2_I(inode)->ip_alloc_sem);
     } else {
         if (write_sem)
             ret = down_write_trylock(&OCFS2_I(inode)->ip_alloc_sem);
         else
             ret = down_read_trylock(&OCFS2_I(inode)->ip_alloc_sem);
 
         if (!ret) {
             ret = -EAGAIN;
             goto out_unlock;
         }
     }
 
     return ret;
 
 out_unlock:
     brelse(*di_bh);
     *di_bh = NULL;
     ocfs2_inode_unlock(inode, meta_level);
 out:
     return ret;
 }
 
 static void ocfs2_inode_unlock_for_extent_tree(struct inode *inode,
                            struct buffer_head **di_bh,
                            int meta_level,
                            int write_sem)
 {
     if (write_sem)
         up_write(&OCFS2_I(inode)->ip_alloc_sem);
     else
         up_read(&OCFS2_I(inode)->ip_alloc_sem);
 
     brelse(*di_bh);
     *di_bh = NULL;
 
     if (meta_level >= 0)
         ocfs2_inode_unlock(inode, meta_level);
 }
 
 static int ocfs2_prepare_inode_for_write(struct file *file,
                      loff_t pos, size_t count, int wait)
 {
     int ret = 0, meta_level = 0, overwrite_io = 0;
     int write_sem = 0;
     struct dentry *dentry = file->f_path.dentry;
     struct inode *inode = d_inode(dentry);
     struct buffer_head *di_bh = NULL;
     u32 cpos;
     u32 clusters;
 
     /*
      * We start with a read level meta lock and only jump to an ex
      * if we need to make modifications here.
      */
     for(;;) {
         ret = ocfs2_inode_lock_for_extent_tree(inode,
                                &di_bh,
                                meta_level,
                                write_sem,
                                wait);
         if (ret < 0) {
             if (ret != -EAGAIN)
                 mlog_errno(ret);
             goto out;
         }
 
         /*
          * Check if IO will overwrite allocated blocks in case
          * IOCB_NOWAIT flag is set.
          */
         if (!wait && !overwrite_io) {
             overwrite_io = 1;
 
             ret = ocfs2_overwrite_io(inode, di_bh, pos, count);
             if (ret < 0) {
                 if (ret != -EAGAIN)
                     mlog_errno(ret);
                 goto out_unlock;
             }
         }
 
         /* Clear suid / sgid if necessary. We do this here
          * instead of later in the write path because
          * remove_suid() calls ->setattr without any hint that
          * we may have already done our cluster locking. Since
          * ocfs2_setattr() *must* take cluster locks to
          * proceed, this will lead us to recursively lock the
          * inode. There's also the dinode i_size state which
          * can be lost via setattr during extending writes (we
          * set inode->i_size at the end of a write. */
         if (should_remove_suid(dentry)) {
             if (meta_level == 0) {
                 ocfs2_inode_unlock_for_extent_tree(inode,
                                    &di_bh,
                                    meta_level,
                                    write_sem);
                 meta_level = 1;
                 continue;
             }
 
             ret = ocfs2_write_remove_suid(inode);
             if (ret < 0) {
                 mlog_errno(ret);
                 goto out_unlock;
             }
         }
 
         ret = ocfs2_check_range_for_refcount(inode, pos, count);
         if (ret == 1) {
             ocfs2_inode_unlock_for_extent_tree(inode,
                                &di_bh,
                                meta_level,
                                write_sem);
             meta_level = 1;
             write_sem = 1;
             ret = ocfs2_inode_lock_for_extent_tree(inode,
                                    &di_bh,
                                    meta_level,
                                    write_sem,
                                    wait);
             if (ret < 0) {
                 if (ret != -EAGAIN)
                     mlog_errno(ret);
                 goto out;
             }
 
             cpos = pos >> OCFS2_SB(inode->i_sb)->s_clustersize_bits;
             clusters =
                 ocfs2_clusters_for_bytes(inode->i_sb, pos + count) - cpos;
             ret = ocfs2_refcount_cow(inode, di_bh, cpos, clusters, UINT_MAX);
         }
 
         if (ret < 0) {
             if (ret != -EAGAIN)
                 mlog_errno(ret);
             goto out_unlock;
         }
 
         break;
     }
 
 out_unlock:
     trace_ocfs2_prepare_inode_for_write(OCFS2_I(inode)->ip_blkno,
                         pos, count, wait);
 
     ocfs2_inode_unlock_for_extent_tree(inode,
                        &di_bh,
                        meta_level,
                        write_sem);
 
 out:
     return ret;
 }
 
 static ssize_t ocfs2_file_write_iter(struct kiocb *iocb,
                     struct iov_iter *from)
 {
     int rw_level;
     ssize_t written = 0;
     ssize_t ret;
     size_t count = iov_iter_count(from);
     struct file *file = iocb->ki_filp;
     struct inode *inode = file_inode(file);
     struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
     int full_coherency = !(osb->s_mount_opt &
                    OCFS2_MOUNT_COHERENCY_BUFFERED);
     void *saved_ki_complete = NULL;
     int append_write = ((iocb->ki_pos + count) >=
             i_size_read(inode) ? 1 : 0);
     int direct_io = iocb->ki_flags & IOCB_DIRECT ? 1 : 0;
     int nowait = iocb->ki_flags & IOCB_NOWAIT ? 1 : 0;
 
     trace_ocfs2_file_write_iter(inode, file, file->f_path.dentry,
         (unsigned long long)OCFS2_I(inode)->ip_blkno,
         file->f_path.dentry->d_name.len,
         file->f_path.dentry->d_name.name,
         (unsigned int)from->nr_segs);   /* GRRRRR */
 
     if (!direct_io && nowait)
         return -EOPNOTSUPP;
 
     if (count == 0)
         return 0;
 
     if (nowait) {
         if (!inode_trylock(inode))
             return -EAGAIN;
     } else
         inode_lock(inode);
 
     /*
      * Concurrent O_DIRECT writes are allowed with
      * mount_option "coherency=buffered".
      * For append write, we must take rw EX.
      */
     rw_level = (!direct_io || full_coherency || append_write);
 
     if (nowait)
         ret = ocfs2_try_rw_lock(inode, rw_level);
     else
         ret = ocfs2_rw_lock(inode, rw_level);
     if (ret < 0) {
         if (ret != -EAGAIN)
             mlog_errno(ret);
         goto out_mutex;
     }
 
     /*
      * O_DIRECT writes with "coherency=full" need to take EX cluster
      * inode_lock to guarantee coherency.
      */
     if (direct_io && full_coherency) {
         /*
          * We need to take and drop the inode lock to force
          * other nodes to drop their caches.  Buffered I/O
          * already does this in write_begin().
          */
         if (nowait)
             ret = ocfs2_try_inode_lock(inode, NULL, 1);
         else
             ret = ocfs2_inode_lock(inode, NULL, 1);
         if (ret < 0) {
             if (ret != -EAGAIN)
                 mlog_errno(ret);
             goto out;
         }
 
         ocfs2_inode_unlock(inode, 1);
     }
 
     ret = generic_write_checks(iocb, from);
     if (ret <= 0) {
         if (ret)
             mlog_errno(ret);
         goto out;
     }
     count = ret;
 
     ret = ocfs2_prepare_inode_for_write(file, iocb->ki_pos, count, !nowait);
     if (ret < 0) {
         if (ret != -EAGAIN)
             mlog_errno(ret);
         goto out;
     }
 
     if (direct_io && !is_sync_kiocb(iocb) &&
         ocfs2_is_io_unaligned(inode, count, iocb->ki_pos)) {
         /*
          * Make it a sync io if it's an unaligned aio.
          */
         saved_ki_complete = xchg(&iocb->ki_complete, NULL);
     }
 
     /* communicate with ocfs2_dio_end_io */
     ocfs2_iocb_set_rw_locked(iocb, rw_level);
 
     written = __generic_file_write_iter(iocb, from);
     /* buffered aio wouldn't have proper lock coverage today */
     BUG_ON(written == -EIOCBQUEUED && !direct_io);
 
     /*
      * deep in g_f_a_w_n()->ocfs2_direct_IO we pass in a ocfs2_dio_end_io
      * function pointer which is called when o_direct io completes so that
      * it can unlock our rw lock.
      * Unfortunately there are error cases which call end_io and others
      * that don't.  so we don't have to unlock the rw_lock if either an
      * async dio is going to do it in the future or an end_io after an
      * error has already done it.
      */
     if ((written == -EIOCBQUEUED) || (!ocfs2_iocb_is_rw_locked(iocb))) {
         rw_level = -1;
     }
 
     if (unlikely(written <= 0))
         goto out;
 
     if (((file->f_flags & O_DSYNC) && !direct_io) ||
         IS_SYNC(inode)) {
         ret = filemap_fdatawrite_range(file->f_mapping,
                            iocb->ki_pos - written,
                            iocb->ki_pos - 1);
         if (ret < 0)
             written = ret;
 
         if (!ret) {
             ret = jbd2_journal_force_commit(osb->journal->j_journal);
             if (ret < 0)
                 written = ret;
         }
 
         if (!ret)
             ret = filemap_fdatawait_range(file->f_mapping,
                               iocb->ki_pos - written,
                               iocb->ki_pos - 1);
     }
 
 out:
     if (saved_ki_complete)
         xchg(&iocb->ki_complete, saved_ki_complete);
 
     if (rw_level != -1)
         ocfs2_rw_unlock(inode, rw_level);
 
 out_mutex:
     inode_unlock(inode);
 
     if (written)
         ret = written;
     return ret;
 }
 
 static ssize_t ocfs2_file_read_iter(struct kiocb *iocb,
                    struct iov_iter *to)
 {
     int ret = 0, rw_level = -1, lock_level = 0;
     struct file *filp = iocb->ki_filp;
     struct inode *inode = file_inode(filp);
     int direct_io = iocb->ki_flags & IOCB_DIRECT ? 1 : 0;
     int nowait = iocb->ki_flags & IOCB_NOWAIT ? 1 : 0;
 
     trace_ocfs2_file_read_iter(inode, filp, filp->f_path.dentry,
             (unsigned long long)OCFS2_I(inode)->ip_blkno,
             filp->f_path.dentry->d_name.len,
             filp->f_path.dentry->d_name.name,
             to->nr_segs);   /* GRRRRR */
 
 
     if (!inode) {
         ret = -EINVAL;
         mlog_errno(ret);
         goto bail;
     }
 
     if (!direct_io && nowait)
         return -EOPNOTSUPP;
 
     /*
      * buffered reads protect themselves in ->read_folio().  O_DIRECT reads
      * need locks to protect pending reads from racing with truncate.
      */
     if (direct_io) {
         if (nowait)
             ret = ocfs2_try_rw_lock(inode, 0);
         else
             ret = ocfs2_rw_lock(inode, 0);
 
         if (ret < 0) {
             if (ret != -EAGAIN)
                 mlog_errno(ret);
             goto bail;
         }
         rw_level = 0;
         /* communicate with ocfs2_dio_end_io */
         ocfs2_iocb_set_rw_locked(iocb, rw_level);
     }
 
     /*
      * We're fine letting folks race truncates and extending
      * writes with read across the cluster, just like they can
      * locally. Hence no rw_lock during read.
      *
      * Take and drop the meta data lock to update inode fields
      * like i_size. This allows the checks down below
      * generic_file_read_iter() a chance of actually working.
      */
     ret = ocfs2_inode_lock_atime(inode, filp->f_path.mnt, &lock_level,
                      !nowait);
     if (ret < 0) {
         if (ret != -EAGAIN)
             mlog_errno(ret);
         goto bail;
     }
     ocfs2_inode_unlock(inode, lock_level);
 
     ret = generic_file_read_iter(iocb, to);
     trace_generic_file_read_iter_ret(ret);
 
     /* buffered aio wouldn't have proper lock coverage today */
     BUG_ON(ret == -EIOCBQUEUED && !direct_io);
 
     /* see ocfs2_file_write_iter */
     if (ret == -EIOCBQUEUED || !ocfs2_iocb_is_rw_locked(iocb)) {
         rw_level = -1;
     }
 
 bail:
     if (rw_level != -1)
         ocfs2_rw_unlock(inode, rw_level);
 
     return ret;
 }
 
 /* Refer generic_file_llseek_unlocked() */
 static loff_t ocfs2_file_llseek(struct file *file, loff_t offset, int whence)
 {
     struct inode *inode = file->f_mapping->host;
     int ret = 0;
 
     inode_lock(inode);
 
     switch (whence) {
     case SEEK_SET:
         break;
     case SEEK_END:
         /* SEEK_END requires the OCFS2 inode lock for the file
          * because it references the file's size.
          */
         ret = ocfs2_inode_lock(inode, NULL, 0);
         if (ret < 0) {
             mlog_errno(ret);
             goto out;
         }
         offset += i_size_read(inode);
         ocfs2_inode_unlock(inode, 0);
         break;
     case SEEK_CUR:
         if (offset == 0) {
             offset = file->f_pos;
             goto out;
         }
         offset += file->f_pos;
         break;
     case SEEK_DATA:
     case SEEK_HOLE:
         ret = ocfs2_seek_data_hole_offset(file, &offset, whence);
         if (ret)
             goto out;
         break;
     default:
         ret = -EINVAL;
         goto out;
     }
 
     offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
 
 out:
     inode_unlock(inode);
     if (ret)
         return ret;
     return offset;
 }
 
 static loff_t ocfs2_remap_file_range(struct file *file_in, loff_t pos_in,
                      struct file *file_out, loff_t pos_out,
                      loff_t len, unsigned int remap_flags)
 {
     struct inode *inode_in = file_inode(file_in);
     struct inode *inode_out = file_inode(file_out);
     struct ocfs2_super *osb = OCFS2_SB(inode_in->i_sb);
     struct buffer_head *in_bh = NULL, *out_bh = NULL;
     bool same_inode = (inode_in == inode_out);
     loff_t remapped = 0;
     ssize_t ret;
 
     if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY))
         return -EINVAL;
     if (!ocfs2_refcount_tree(osb))
         return -EOPNOTSUPP;
     if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
         return -EROFS;
 
     /* Lock both files against IO */
     ret = ocfs2_reflink_inodes_lock(inode_in, &in_bh, inode_out, &out_bh);
     if (ret)
         return ret;
 
     /* Check file eligibility and prepare for block sharing. */
     ret = -EINVAL;
     if ((OCFS2_I(inode_in)->ip_flags & OCFS2_INODE_SYSTEM_FILE) ||
         (OCFS2_I(inode_out)->ip_flags & OCFS2_INODE_SYSTEM_FILE))
         goto out_unlock;
 
     ret = generic_remap_file_range_prep(file_in, pos_in, file_out, pos_out,
             &len, remap_flags);
     if (ret < 0 || len == 0)
         goto out_unlock;
 
     /* Lock out changes to the allocation maps and remap. */
     down_write(&OCFS2_I(inode_in)->ip_alloc_sem);
     if (!same_inode)
         down_write_nested(&OCFS2_I(inode_out)->ip_alloc_sem,
                   SINGLE_DEPTH_NESTING);
 
     /* Zap any page cache for the destination file's range. */
     truncate_inode_pages_range(&inode_out->i_data,
                    round_down(pos_out, PAGE_SIZE),
                    round_up(pos_out + len, PAGE_SIZE) - 1);
 
     remapped = ocfs2_reflink_remap_blocks(inode_in, in_bh, pos_in,
             inode_out, out_bh, pos_out, len);
     up_write(&OCFS2_I(inode_in)->ip_alloc_sem);
     if (!same_inode)
         up_write(&OCFS2_I(inode_out)->ip_alloc_sem);
     if (remapped < 0) {
         ret = remapped;
         mlog_errno(ret);
         goto out_unlock;
     }
 
     /*
      * Empty the extent map so that we may get the right extent
      * record from the disk.
      */
     ocfs2_extent_map_trunc(inode_in, 0);
     ocfs2_extent_map_trunc(inode_out, 0);
 
     ret = ocfs2_reflink_update_dest(inode_out, out_bh, pos_out + len);
     if (ret) {
         mlog_errno(ret);
         goto out_unlock;
     }
 
 out_unlock:
     ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh);
     return remapped > 0 ? remapped : ret;
 }
 
 const struct inode_operations ocfs2_file_iops = {
     .setattr    = ocfs2_setattr,
     .getattr    = ocfs2_getattr,
     .permission = ocfs2_permission,
     .listxattr  = ocfs2_listxattr,
     .fiemap     = ocfs2_fiemap,
     .get_acl    = ocfs2_iop_get_acl,
     .set_acl    = ocfs2_iop_set_acl,
     .fileattr_get   = ocfs2_fileattr_get,
     .fileattr_set   = ocfs2_fileattr_set,
 };
 
 const struct inode_operations ocfs2_special_file_iops = {
     .setattr    = ocfs2_setattr,
     .getattr    = ocfs2_getattr,
     .permission = ocfs2_permission,
     .get_acl    = ocfs2_iop_get_acl,
     .set_acl    = ocfs2_iop_set_acl,
 };
 
 /*
  * Other than ->lock, keep ocfs2_fops and ocfs2_dops in sync with
  * ocfs2_fops_no_plocks and ocfs2_dops_no_plocks!
  */
 const struct file_operations ocfs2_fops = {
     .llseek     = ocfs2_file_llseek,
     .mmap       = ocfs2_mmap,
     .fsync      = ocfs2_sync_file,
     .release    = ocfs2_file_release,
     .open       = ocfs2_file_open,
     .read_iter  = ocfs2_file_read_iter,
     .write_iter = ocfs2_file_write_iter,
     .unlocked_ioctl = ocfs2_ioctl,
 #ifdef CONFIG_COMPAT
     .compat_ioctl   = ocfs2_compat_ioctl,
 #endif
     .lock       = ocfs2_lock,
     .flock      = ocfs2_flock,
     .splice_read    = generic_file_splice_read,
     .splice_write   = iter_file_splice_write,
     .fallocate  = ocfs2_fallocate,
     .remap_file_range = ocfs2_remap_file_range,
 };
 
 const struct file_operations ocfs2_dops = {
     .llseek     = generic_file_llseek,
     .read       = generic_read_dir,
     .iterate    = ocfs2_readdir,
     .fsync      = ocfs2_sync_file,
     .release    = ocfs2_dir_release,
     .open       = ocfs2_dir_open,
     .unlocked_ioctl = ocfs2_ioctl,
 #ifdef CONFIG_COMPAT
     .compat_ioctl   = ocfs2_compat_ioctl,
 #endif
     .lock       = ocfs2_lock,
     .flock      = ocfs2_flock,
 };
 
 /*
  * POSIX-lockless variants of our file_operations.
  *
  * These will be used if the underlying cluster stack does not support
  * posix file locking, if the user passes the "localflocks" mount
  * option, or if we have a local-only fs.
  *
  * ocfs2_flock is in here because all stacks handle UNIX file locks,
  * so we still want it in the case of no stack support for
  * plocks. Internally, it will do the right thing when asked to ignore
  * the cluster.
  */
 const struct file_operations ocfs2_fops_no_plocks = {
     .llseek     = ocfs2_file_llseek,
     .mmap       = ocfs2_mmap,
     .fsync      = ocfs2_sync_file,
     .release    = ocfs2_file_release,
     .open       = ocfs2_file_open,
     .read_iter  = ocfs2_file_read_iter,
     .write_iter = ocfs2_file_write_iter,
     .unlocked_ioctl = ocfs2_ioctl,
 #ifdef CONFIG_COMPAT
     .compat_ioctl   = ocfs2_compat_ioctl,
 #endif
     .flock      = ocfs2_flock,
     .splice_read    = generic_file_splice_read,
     .splice_write   = iter_file_splice_write,
     .fallocate  = ocfs2_fallocate,
     .remap_file_range = ocfs2_remap_file_range,
 };
 
 const struct file_operations ocfs2_dops_no_plocks = {
     .llseek     = generic_file_llseek,
     .read       = generic_read_dir,
     .iterate    = ocfs2_readdir,
     .fsync      = ocfs2_sync_file,
     .release    = ocfs2_dir_release,
     .open       = ocfs2_dir_open,
     .unlocked_ioctl = ocfs2_ioctl,
 #ifdef CONFIG_COMPAT
     .compat_ioctl   = ocfs2_compat_ioctl,
 #endif
     .flock      = ocfs2_flock,
 };