Merge tag 'regmap-fix-v4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git...
[cascardo/linux.git] / fs / xfs / xfs_reflink.c
index 5965e94..a279b4e 100644 (file)
@@ -182,7 +182,8 @@ xfs_reflink_trim_around_shared(
        if (!xfs_is_reflink_inode(ip) ||
            ISUNWRITTEN(irec) ||
            irec->br_startblock == HOLESTARTBLOCK ||
-           irec->br_startblock == DELAYSTARTBLOCK) {
+           irec->br_startblock == DELAYSTARTBLOCK ||
+           isnullstartblock(irec->br_startblock)) {
                *shared = false;
                return 0;
        }
@@ -227,50 +228,54 @@ xfs_reflink_trim_around_shared(
        }
 }
 
-/* Create a CoW reservation for a range of blocks within a file. */
-static int
-__xfs_reflink_reserve_cow(
+/*
+ * Trim the passed in imap to the next shared/unshared extent boundary, and
+ * if imap->br_startoff points to a shared extent reserve space for it in the
+ * COW fork.  In this case *shared is set to true, else to false.
+ *
+ * Note that imap will always contain the block numbers for the existing blocks
+ * in the data fork, as the upper layers need them for read-modify-write
+ * operations.
+ */
+int
+xfs_reflink_reserve_cow(
        struct xfs_inode        *ip,
-       xfs_fileoff_t           *offset_fsb,
-       xfs_fileoff_t           end_fsb,
-       bool                    *skipped)
+       struct xfs_bmbt_irec    *imap,
+       bool                    *shared)
 {
-       struct xfs_bmbt_irec    got, prev, imap;
-       xfs_fileoff_t           orig_end_fsb;
-       int                     nimaps, eof = 0, error = 0;
-       bool                    shared = false, trimmed = false;
+       struct xfs_bmbt_irec    got, prev;
+       xfs_fileoff_t           end_fsb, orig_end_fsb;
+       int                     eof = 0, error = 0;
+       bool                    trimmed;
        xfs_extnum_t            idx;
        xfs_extlen_t            align;
 
-       /* Already reserved?  Skip the refcount btree access. */
-       xfs_bmap_search_extents(ip, *offset_fsb, XFS_COW_FORK, &eof, &idx,
+       /*
+        * Search the COW fork extent list first.  This serves two purposes:
+        * first this implement the speculative preallocation using cowextisze,
+        * so that we also unshared block adjacent to shared blocks instead
+        * of just the shared blocks themselves.  Second the lookup in the
+        * extent list is generally faster than going out to the shared extent
+        * tree.
+        */
+       xfs_bmap_search_extents(ip, imap->br_startoff, XFS_COW_FORK, &eof, &idx,
                        &got, &prev);
-       if (!eof && got.br_startoff <= *offset_fsb) {
-               end_fsb = orig_end_fsb = got.br_startoff + got.br_blockcount;
-               trace_xfs_reflink_cow_found(ip, &got);
-               goto done;
-       }
+       if (!eof && got.br_startoff <= imap->br_startoff) {
+               trace_xfs_reflink_cow_found(ip, imap);
+               xfs_trim_extent(imap, got.br_startoff, got.br_blockcount);
 
-       /* Read extent from the source file. */
-       nimaps = 1;
-       error = xfs_bmapi_read(ip, *offset_fsb, end_fsb - *offset_fsb,
-                       &imap, &nimaps, 0);
-       if (error)
-               goto out_unlock;
-       ASSERT(nimaps == 1);
+               *shared = true;
+               return 0;
+       }
 
        /* Trim the mapping to the nearest shared extent boundary. */
-       error = xfs_reflink_trim_around_shared(ip, &imap, &shared, &trimmed);
+       error = xfs_reflink_trim_around_shared(ip, imap, shared, &trimmed);
        if (error)
-               goto out_unlock;
-
-       end_fsb = orig_end_fsb = imap.br_startoff + imap.br_blockcount;
+               return error;
 
        /* Not shared?  Just report the (potentially capped) extent. */
-       if (!shared) {
-               *skipped = true;
-               goto done;
-       }
+       if (!*shared)
+               return 0;
 
        /*
         * Fork all the shared blocks from our write offset until the end of
@@ -278,72 +283,38 @@ __xfs_reflink_reserve_cow(
         */
        error = xfs_qm_dqattach_locked(ip, 0);
        if (error)
-               goto out_unlock;
+               return error;
+
+       end_fsb = orig_end_fsb = imap->br_startoff + imap->br_blockcount;
 
        align = xfs_eof_alignment(ip, xfs_get_cowextsz_hint(ip));
        if (align)
                end_fsb = roundup_64(end_fsb, align);
 
 retry:
-       error = xfs_bmapi_reserve_delalloc(ip, XFS_COW_FORK, *offset_fsb,
-                       end_fsb - *offset_fsb, &got,
-                       &prev, &idx, eof);
+       error = xfs_bmapi_reserve_delalloc(ip, XFS_COW_FORK, imap->br_startoff,
+                       end_fsb - imap->br_startoff, &got, &prev, &idx, eof);
        switch (error) {
        case 0:
                break;
        case -ENOSPC:
        case -EDQUOT:
                /* retry without any preallocation */
-               trace_xfs_reflink_cow_enospc(ip, &imap);
+               trace_xfs_reflink_cow_enospc(ip, imap);
                if (end_fsb != orig_end_fsb) {
                        end_fsb = orig_end_fsb;
                        goto retry;
                }
                /*FALLTHRU*/
        default:
-               goto out_unlock;
+               return error;
        }
 
        if (end_fsb != orig_end_fsb)
                xfs_inode_set_cowblocks_tag(ip);
 
        trace_xfs_reflink_cow_alloc(ip, &got);
-done:
-       *offset_fsb = end_fsb;
-out_unlock:
-       return error;
-}
-
-/* Create a CoW reservation for part of a file. */
-int
-xfs_reflink_reserve_cow_range(
-       struct xfs_inode        *ip,
-       xfs_off_t               offset,
-       xfs_off_t               count)
-{
-       struct xfs_mount        *mp = ip->i_mount;
-       xfs_fileoff_t           offset_fsb, end_fsb;
-       bool                    skipped = false;
-       int                     error;
-
-       trace_xfs_reflink_reserve_cow_range(ip, offset, count);
-
-       offset_fsb = XFS_B_TO_FSBT(mp, offset);
-       end_fsb = XFS_B_TO_FSB(mp, offset + count);
-
-       xfs_ilock(ip, XFS_ILOCK_EXCL);
-       while (offset_fsb < end_fsb) {
-               error = __xfs_reflink_reserve_cow(ip, &offset_fsb, end_fsb,
-                               &skipped);
-               if (error) {
-                       trace_xfs_reflink_reserve_cow_range_error(ip, error,
-                               _RET_IP_);
-                       break;
-               }
-       }
-       xfs_iunlock(ip, XFS_ILOCK_EXCL);
-
-       return error;
+       return 0;
 }
 
 /* Allocate all CoW reservations covering a range of blocks in a file. */
@@ -358,9 +329,8 @@ __xfs_reflink_allocate_cow(
        struct xfs_defer_ops    dfops;
        struct xfs_trans        *tp;
        xfs_fsblock_t           first_block;
-       xfs_fileoff_t           next_fsb;
        int                     nimaps = 1, error;
-       bool                    skipped = false;
+       bool                    shared;
 
        xfs_defer_init(&dfops, &first_block);
 
@@ -371,33 +341,38 @@ __xfs_reflink_allocate_cow(
 
        xfs_ilock(ip, XFS_ILOCK_EXCL);
 
-       next_fsb = *offset_fsb;
-       error = __xfs_reflink_reserve_cow(ip, &next_fsb, end_fsb, &skipped);
+       /* Read extent from the source file. */
+       nimaps = 1;
+       error = xfs_bmapi_read(ip, *offset_fsb, end_fsb - *offset_fsb,
+                       &imap, &nimaps, 0);
+       if (error)
+               goto out_unlock;
+       ASSERT(nimaps == 1);
+
+       error = xfs_reflink_reserve_cow(ip, &imap, &shared);
        if (error)
                goto out_trans_cancel;
 
-       if (skipped) {
-               *offset_fsb = next_fsb;
+       if (!shared) {
+               *offset_fsb = imap.br_startoff + imap.br_blockcount;
                goto out_trans_cancel;
        }
 
        xfs_trans_ijoin(tp, ip, 0);
-       error = xfs_bmapi_write(tp, ip, *offset_fsb, next_fsb - *offset_fsb,
+       error = xfs_bmapi_write(tp, ip, imap.br_startoff, imap.br_blockcount,
                        XFS_BMAPI_COWFORK, &first_block,
                        XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK),
                        &imap, &nimaps, &dfops);
        if (error)
                goto out_trans_cancel;
 
-       /* We might not have been able to map the whole delalloc extent */
-       *offset_fsb = min(*offset_fsb + imap.br_blockcount, next_fsb);
-
        error = xfs_defer_finish(&tp, &dfops, NULL);
        if (error)
                goto out_trans_cancel;
 
        error = xfs_trans_commit(tp);
 
+       *offset_fsb = imap.br_startoff + imap.br_blockcount;
 out_unlock:
        xfs_iunlock(ip, XFS_ILOCK_EXCL);
        return error;
@@ -536,58 +511,49 @@ xfs_reflink_cancel_cow_blocks(
        xfs_fileoff_t                   offset_fsb,
        xfs_fileoff_t                   end_fsb)
 {
-       struct xfs_bmbt_irec            irec;
-       xfs_filblks_t                   count_fsb;
+       struct xfs_ifork                *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
+       struct xfs_bmbt_irec            got, prev, del;
+       xfs_extnum_t                    idx;
        xfs_fsblock_t                   firstfsb;
        struct xfs_defer_ops            dfops;
-       int                             error = 0;
-       int                             nimaps;
+       int                             error = 0, eof = 0;
 
        if (!xfs_is_reflink_inode(ip))
                return 0;
 
-       /* Go find the old extent in the CoW fork. */
-       while (offset_fsb < end_fsb) {
-               nimaps = 1;
-               count_fsb = (xfs_filblks_t)(end_fsb - offset_fsb);
-               error = xfs_bmapi_read(ip, offset_fsb, count_fsb, &irec,
-                               &nimaps, XFS_BMAPI_COWFORK);
-               if (error)
-                       break;
-               ASSERT(nimaps == 1);
-
-               trace_xfs_reflink_cancel_cow(ip, &irec);
+       xfs_bmap_search_extents(ip, offset_fsb, XFS_COW_FORK, &eof, &idx,
+                       &got, &prev);
+       if (eof)
+               return 0;
 
-               if (irec.br_startblock == DELAYSTARTBLOCK) {
-                       /* Free a delayed allocation. */
-                       xfs_mod_fdblocks(ip->i_mount, irec.br_blockcount,
-                                       false);
-                       ip->i_delayed_blks -= irec.br_blockcount;
+       while (got.br_startoff < end_fsb) {
+               del = got;
+               xfs_trim_extent(&del, offset_fsb, end_fsb - offset_fsb);
+               trace_xfs_reflink_cancel_cow(ip, &del);
 
-                       /* Remove the mapping from the CoW fork. */
-                       error = xfs_bunmapi_cow(ip, &irec);
+               if (isnullstartblock(del.br_startblock)) {
+                       error = xfs_bmap_del_extent_delay(ip, XFS_COW_FORK,
+                                       &idx, &got, &del);
                        if (error)
                                break;
-               } else if (irec.br_startblock == HOLESTARTBLOCK) {
-                       /* empty */
                } else {
                        xfs_trans_ijoin(*tpp, ip, 0);
                        xfs_defer_init(&dfops, &firstfsb);
 
                        /* Free the CoW orphan record. */
                        error = xfs_refcount_free_cow_extent(ip->i_mount,
-                                       &dfops, irec.br_startblock,
-                                       irec.br_blockcount);
+                                       &dfops, del.br_startblock,
+                                       del.br_blockcount);
                        if (error)
                                break;
 
                        xfs_bmap_add_free(ip->i_mount, &dfops,
-                                       irec.br_startblock, irec.br_blockcount,
+                                       del.br_startblock, del.br_blockcount,
                                        NULL);
 
                        /* Update quota accounting */
                        xfs_trans_mod_dquot_byino(*tpp, ip, XFS_TRANS_DQ_BCOUNT,
-                                       -(long)irec.br_blockcount);
+                                       -(long)del.br_blockcount);
 
                        /* Roll the transaction */
                        error = xfs_defer_finish(tpp, &dfops, ip);
@@ -597,15 +563,18 @@ xfs_reflink_cancel_cow_blocks(
                        }
 
                        /* Remove the mapping from the CoW fork. */
-                       error = xfs_bunmapi_cow(ip, &irec);
-                       if (error)
-                               break;
+                       xfs_bmap_del_extent_cow(ip, &idx, &got, &del);
                }
 
-               /* Roll on... */
-               offset_fsb = irec.br_startoff + irec.br_blockcount;
+               if (++idx >= ifp->if_bytes / sizeof(struct xfs_bmbt_rec))
+                       break;
+               xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx), &got);
        }
 
+       /* clear tag if cow fork is emptied */
+       if (!ifp->if_bytes)
+               xfs_inode_clear_cowblocks_tag(ip);
+
        return error;
 }
 
@@ -668,25 +637,26 @@ xfs_reflink_end_cow(
        xfs_off_t                       offset,
        xfs_off_t                       count)
 {
-       struct xfs_bmbt_irec            irec;
-       struct xfs_bmbt_irec            uirec;
+       struct xfs_ifork                *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
+       struct xfs_bmbt_irec            got, prev, del;
        struct xfs_trans                *tp;
        xfs_fileoff_t                   offset_fsb;
        xfs_fileoff_t                   end_fsb;
-       xfs_filblks_t                   count_fsb;
        xfs_fsblock_t                   firstfsb;
        struct xfs_defer_ops            dfops;
-       int                             error;
+       int                             error, eof = 0;
        unsigned int                    resblks;
-       xfs_filblks_t                   ilen;
        xfs_filblks_t                   rlen;
-       int                             nimaps;
+       xfs_extnum_t                    idx;
 
        trace_xfs_reflink_end_cow(ip, offset, count);
 
+       /* No COW extents?  That's easy! */
+       if (ifp->if_bytes == 0)
+               return 0;
+
        offset_fsb = XFS_B_TO_FSBT(ip->i_mount, offset);
        end_fsb = XFS_B_TO_FSB(ip->i_mount, offset + count);
-       count_fsb = (xfs_filblks_t)(end_fsb - offset_fsb);
 
        /* Start a rolling transaction to switch the mappings */
        resblks = XFS_EXTENTADD_SPACE_RES(ip->i_mount, XFS_DATA_FORK);
@@ -698,72 +668,65 @@ xfs_reflink_end_cow(
        xfs_ilock(ip, XFS_ILOCK_EXCL);
        xfs_trans_ijoin(tp, ip, 0);
 
-       /* Go find the old extent in the CoW fork. */
-       while (offset_fsb < end_fsb) {
-               /* Read extent from the source file */
-               nimaps = 1;
-               count_fsb = (xfs_filblks_t)(end_fsb - offset_fsb);
-               error = xfs_bmapi_read(ip, offset_fsb, count_fsb, &irec,
-                               &nimaps, XFS_BMAPI_COWFORK);
-               if (error)
-                       goto out_cancel;
-               ASSERT(nimaps == 1);
+       xfs_bmap_search_extents(ip, end_fsb - 1, XFS_COW_FORK, &eof, &idx,
+                       &got, &prev);
 
-               ASSERT(irec.br_startblock != DELAYSTARTBLOCK);
-               trace_xfs_reflink_cow_remap(ip, &irec);
+       /* If there is a hole at end_fsb - 1 go to the previous extent */
+       if (eof || got.br_startoff > end_fsb) {
+               ASSERT(idx > 0);
+               xfs_bmbt_get_all(xfs_iext_get_ext(ifp, --idx), &got);
+       }
 
-               /*
-                * We can have a hole in the CoW fork if part of a directio
-                * write is CoW but part of it isn't.
-                */
-               rlen = ilen = irec.br_blockcount;
-               if (irec.br_startblock == HOLESTARTBLOCK)
+       /* Walk backwards until we're out of the I/O range... */
+       while (got.br_startoff + got.br_blockcount > offset_fsb) {
+               del = got;
+               xfs_trim_extent(&del, offset_fsb, end_fsb - offset_fsb);
+
+               /* Extent delete may have bumped idx forward */
+               if (!del.br_blockcount) {
+                       idx--;
                        goto next_extent;
+               }
+
+               ASSERT(!isnullstartblock(got.br_startblock));
 
                /* Unmap the old blocks in the data fork. */
-               while (rlen) {
-                       xfs_defer_init(&dfops, &firstfsb);
-                       error = __xfs_bunmapi(tp, ip, irec.br_startoff,
-                                       &rlen, 0, 1, &firstfsb, &dfops);
-                       if (error)
-                               goto out_defer;
-
-                       /*
-                        * Trim the extent to whatever got unmapped.
-                        * Remember, bunmapi works backwards.
-                        */
-                       uirec.br_startblock = irec.br_startblock + rlen;
-                       uirec.br_startoff = irec.br_startoff + rlen;
-                       uirec.br_blockcount = irec.br_blockcount - rlen;
-                       irec.br_blockcount = rlen;
-                       trace_xfs_reflink_cow_remap_piece(ip, &uirec);
+               xfs_defer_init(&dfops, &firstfsb);
+               rlen = del.br_blockcount;
+               error = __xfs_bunmapi(tp, ip, del.br_startoff, &rlen, 0, 1,
+                               &firstfsb, &dfops);
+               if (error)
+                       goto out_defer;
 
-                       /* Free the CoW orphan record. */
-                       error = xfs_refcount_free_cow_extent(tp->t_mountp,
-                                       &dfops, uirec.br_startblock,
-                                       uirec.br_blockcount);
-                       if (error)
-                               goto out_defer;
+               /* Trim the extent to whatever got unmapped. */
+               if (rlen) {
+                       xfs_trim_extent(&del, del.br_startoff + rlen,
+                               del.br_blockcount - rlen);
+               }
+               trace_xfs_reflink_cow_remap(ip, &del);
 
-                       /* Map the new blocks into the data fork. */
-                       error = xfs_bmap_map_extent(tp->t_mountp, &dfops,
-                                       ip, &uirec);
-                       if (error)
-                               goto out_defer;
+               /* Free the CoW orphan record. */
+               error = xfs_refcount_free_cow_extent(tp->t_mountp, &dfops,
+                               del.br_startblock, del.br_blockcount);
+               if (error)
+                       goto out_defer;
 
-                       /* Remove the mapping from the CoW fork. */
-                       error = xfs_bunmapi_cow(ip, &uirec);
-                       if (error)
-                               goto out_defer;
+               /* Map the new blocks into the data fork. */
+               error = xfs_bmap_map_extent(tp->t_mountp, &dfops, ip, &del);
+               if (error)
+                       goto out_defer;
 
-                       error = xfs_defer_finish(&tp, &dfops, ip);
-                       if (error)
-                               goto out_defer;
-               }
+               /* Remove the mapping from the CoW fork. */
+               xfs_bmap_del_extent_cow(ip, &idx, &got, &del);
+
+               error = xfs_defer_finish(&tp, &dfops, ip);
+               if (error)
+                       goto out_defer;
 
 next_extent:
-               /* Roll on... */
-               offset_fsb = irec.br_startoff + ilen;
+               if (idx < 0)
+                       break;
+               xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx), &got);
        }
 
        error = xfs_trans_commit(tp);
@@ -774,7 +737,6 @@ next_extent:
 
 out_defer:
        xfs_defer_cancel(&dfops);
-out_cancel:
        xfs_trans_cancel(tp);
        xfs_iunlock(ip, XFS_ILOCK_EXCL);
 out:
@@ -1312,19 +1274,26 @@ out_error:
  */
 int
 xfs_reflink_remap_range(
-       struct xfs_inode        *src,
-       xfs_off_t               srcoff,
-       struct xfs_inode        *dest,
-       xfs_off_t               destoff,
-       xfs_off_t               len,
-       unsigned int            flags)
+       struct file             *file_in,
+       loff_t                  pos_in,
+       struct file             *file_out,
+       loff_t                  pos_out,
+       u64                     len,
+       bool                    is_dedupe)
 {
+       struct inode            *inode_in = file_inode(file_in);
+       struct xfs_inode        *src = XFS_I(inode_in);
+       struct inode            *inode_out = file_inode(file_out);
+       struct xfs_inode        *dest = XFS_I(inode_out);
        struct xfs_mount        *mp = src->i_mount;
+       loff_t                  bs = inode_out->i_sb->s_blocksize;
+       bool                    same_inode = (inode_in == inode_out);
        xfs_fileoff_t           sfsbno, dfsbno;
        xfs_filblks_t           fsblen;
-       int                     error;
        xfs_extlen_t            cowextsize;
-       bool                    is_same;
+       loff_t                  isize;
+       ssize_t                 ret;
+       loff_t                  blen;
 
        if (!xfs_sb_version_hasreflink(&mp->m_sb))
                return -EOPNOTSUPP;
@@ -1332,17 +1301,8 @@ xfs_reflink_remap_range(
        if (XFS_FORCED_SHUTDOWN(mp))
                return -EIO;
 
-       /* Don't reflink realtime inodes */
-       if (XFS_IS_REALTIME_INODE(src) || XFS_IS_REALTIME_INODE(dest))
-               return -EINVAL;
-
-       if (flags & ~XFS_REFLINK_ALL)
-               return -EINVAL;
-
-       trace_xfs_reflink_remap_range(src, srcoff, len, dest, destoff);
-
        /* Lock both files against IO */
-       if (src->i_ino == dest->i_ino) {
+       if (same_inode) {
                xfs_ilock(src, XFS_IOLOCK_EXCL);
                xfs_ilock(src, XFS_MMAPLOCK_EXCL);
        } else {
@@ -1350,39 +1310,126 @@ xfs_reflink_remap_range(
                xfs_lock_two_inodes(src, dest, XFS_MMAPLOCK_EXCL);
        }
 
+       /* Don't touch certain kinds of inodes */
+       ret = -EPERM;
+       if (IS_IMMUTABLE(inode_out))
+               goto out_unlock;
+
+       ret = -ETXTBSY;
+       if (IS_SWAPFILE(inode_in) || IS_SWAPFILE(inode_out))
+               goto out_unlock;
+
+
+       /* Don't reflink dirs, pipes, sockets... */
+       ret = -EISDIR;
+       if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode))
+               goto out_unlock;
+       ret = -EINVAL;
+       if (S_ISFIFO(inode_in->i_mode) || S_ISFIFO(inode_out->i_mode))
+               goto out_unlock;
+       if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
+               goto out_unlock;
+
+       /* Don't reflink realtime inodes */
+       if (XFS_IS_REALTIME_INODE(src) || XFS_IS_REALTIME_INODE(dest))
+               goto out_unlock;
+
+       /* Don't share DAX file data for now. */
+       if (IS_DAX(inode_in) || IS_DAX(inode_out))
+               goto out_unlock;
+
+       /* Are we going all the way to the end? */
+       isize = i_size_read(inode_in);
+       if (isize == 0) {
+               ret = 0;
+               goto out_unlock;
+       }
+
+       if (len == 0)
+               len = isize - pos_in;
+
+       /* Ensure offsets don't wrap and the input is inside i_size */
+       if (pos_in + len < pos_in || pos_out + len < pos_out ||
+           pos_in + len > isize)
+               goto out_unlock;
+
+       /* Don't allow dedupe past EOF in the dest file */
+       if (is_dedupe) {
+               loff_t  disize;
+
+               disize = i_size_read(inode_out);
+               if (pos_out >= disize || pos_out + len > disize)
+                       goto out_unlock;
+       }
+
+       /* If we're linking to EOF, continue to the block boundary. */
+       if (pos_in + len == isize)
+               blen = ALIGN(isize, bs) - pos_in;
+       else
+               blen = len;
+
+       /* Only reflink if we're aligned to block boundaries */
+       if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_in + blen, bs) ||
+           !IS_ALIGNED(pos_out, bs) || !IS_ALIGNED(pos_out + blen, bs))
+               goto out_unlock;
+
+       /* Don't allow overlapped reflink within the same file */
+       if (same_inode) {
+               if (pos_out + blen > pos_in && pos_out < pos_in + blen)
+                       goto out_unlock;
+       }
+
+       /* Wait for the completion of any pending IOs on both files */
+       inode_dio_wait(inode_in);
+       if (!same_inode)
+               inode_dio_wait(inode_out);
+
+       ret = filemap_write_and_wait_range(inode_in->i_mapping,
+                       pos_in, pos_in + len - 1);
+       if (ret)
+               goto out_unlock;
+
+       ret = filemap_write_and_wait_range(inode_out->i_mapping,
+                       pos_out, pos_out + len - 1);
+       if (ret)
+               goto out_unlock;
+
+       trace_xfs_reflink_remap_range(src, pos_in, len, dest, pos_out);
+
        /*
         * Check that the extents are the same.
         */
-       if (flags & XFS_REFLINK_DEDUPE) {
-               is_same = false;
-               error = xfs_compare_extents(VFS_I(src), srcoff, VFS_I(dest),
-                               destoff, len, &is_same);
-               if (error)
-                       goto out_error;
+       if (is_dedupe) {
+               bool            is_same = false;
+
+               ret = xfs_compare_extents(inode_in, pos_in, inode_out, pos_out,
+                               len, &is_same);
+               if (ret)
+                       goto out_unlock;
                if (!is_same) {
-                       error = -EBADE;
-                       goto out_error;
+                       ret = -EBADE;
+                       goto out_unlock;
                }
        }
 
-       error = xfs_reflink_set_inode_flag(src, dest);
-       if (error)
-               goto out_error;
+       ret = xfs_reflink_set_inode_flag(src, dest);
+       if (ret)
+               goto out_unlock;
 
        /*
         * Invalidate the page cache so that we can clear any CoW mappings
         * in the destination file.
         */
-       truncate_inode_pages_range(&VFS_I(dest)->i_data, destoff,
-                                  PAGE_ALIGN(destoff + len) - 1);
+       truncate_inode_pages_range(&inode_out->i_data, pos_out,
+                                  PAGE_ALIGN(pos_out + len) - 1);
 
-       dfsbno = XFS_B_TO_FSBT(mp, destoff);
-       sfsbno = XFS_B_TO_FSBT(mp, srcoff);
+       dfsbno = XFS_B_TO_FSBT(mp, pos_out);
+       sfsbno = XFS_B_TO_FSBT(mp, pos_in);
        fsblen = XFS_B_TO_FSB(mp, len);
-       error = xfs_reflink_remap_blocks(src, sfsbno, dest, dfsbno, fsblen,
-                       destoff + len);
-       if (error)
-               goto out_error;
+       ret = xfs_reflink_remap_blocks(src, sfsbno, dest, dfsbno, fsblen,
+                       pos_out + len);
+       if (ret)
+               goto out_unlock;
 
        /*
         * Carry the cowextsize hint from src to dest if we're sharing the
@@ -1390,26 +1437,24 @@ xfs_reflink_remap_range(
         * has a cowextsize hint, and the destination file does not.
         */
        cowextsize = 0;
-       if (srcoff == 0 && len == i_size_read(VFS_I(src)) &&
+       if (pos_in == 0 && len == i_size_read(inode_in) &&
            (src->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) &&
-           destoff == 0 && len >= i_size_read(VFS_I(dest)) &&
+           pos_out == 0 && len >= i_size_read(inode_out) &&
            !(dest->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE))
                cowextsize = src->i_d.di_cowextsize;
 
-       error = xfs_reflink_update_dest(dest, destoff + len, cowextsize);
-       if (error)
-               goto out_error;
+       ret = xfs_reflink_update_dest(dest, pos_out + len, cowextsize);
 
-out_error:
+out_unlock:
        xfs_iunlock(src, XFS_MMAPLOCK_EXCL);
        xfs_iunlock(src, XFS_IOLOCK_EXCL);
        if (src->i_ino != dest->i_ino) {
                xfs_iunlock(dest, XFS_MMAPLOCK_EXCL);
                xfs_iunlock(dest, XFS_IOLOCK_EXCL);
        }
-       if (error)
-               trace_xfs_reflink_remap_range_error(dest, error, _RET_IP_);
-       return error;
+       if (ret)
+               trace_xfs_reflink_remap_range_error(dest, ret, _RET_IP_);
+       return ret;
 }
 
 /*