[PATCH 3/2] delalloc support for xfs fiemap

[Eric Sandeen <sandeen@xxxxxxxxxxx>]

Ok, got the kinks worked out of the delalloc portion of the
fiemap hookup I think.

This introduces a new input flag (BMV_IF_DELALLOC) and output
flag (BMV_OF_DELALLOC) to request & show the delayed allocation
segments.

Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxxx>
---

Index: linux-2.6.27.x86_64/fs/xfs/linux-2.6/xfs_iops.c
===================================================================
--- linux-2.6.27.x86_64.orig/fs/xfs/linux-2.6/xfs_iops.c
+++ linux-2.6.27.x86_64/fs/xfs/linux-2.6/xfs_iops.c
@@ -685,6 +685,10 @@ STATIC int xfs_fiemap_format(
 
        if (bmv->bmv_oflags & BMV_OF_PREALLOC)
                fiemap_flags |= FIEMAP_EXTENT_UNWRITTEN;
+       else if (bmv->bmv_oflags & BMV_OF_DELALLOC) {
+               fiemap_flags |= FIEMAP_EXTENT_DELALLOC;
+               physical = 0;   /* no block yet */
+       }
        if (bmv->bmv_oflags & BMV_OF_LAST)
                fiemap_flags |= FIEMAP_EXTENT_LAST;
 
@@ -722,6 +726,8 @@ xfs_vn_fiemap(
        bm.bmv_iflags = BMV_IF_PREALLOC;
        if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR)
                bm.bmv_iflags |= BMV_IF_ATTRFORK;
+       if (!(fieinfo->fi_flags & FIEMAP_FLAG_SYNC))
+               bm.bmv_iflags |= BMV_IF_DELALLOC;
 
        error = xfs_getbmap(ip, &bm, xfs_fiemap_format, fieinfo);
        if (error)
Index: linux-2.6.27.x86_64/fs/xfs/xfs_bmap.c
===================================================================
--- linux-2.6.27.x86_64.orig/fs/xfs/xfs_bmap.c
+++ linux-2.6.27.x86_64/fs/xfs/xfs_bmap.c
@@ -5827,6 +5827,7 @@ xfs_getbmap(
                                                 * preallocated data space */
        int                     sh_unwritten;   /* true, if unwritten */
                                                /* extents listed separately */
+       int                     sh_delalloc;    /* show delayed extents */
        int                     iflags;         /* interface flags */
        int                     bmapi_flags;    /* flags for xfs_bmapi */
 
@@ -5835,6 +5836,7 @@ xfs_getbmap(
 
        whichfork = iflags & BMV_IF_ATTRFORK ? XFS_ATTR_FORK : XFS_DATA_FORK;
        sh_unwritten = (iflags & BMV_IF_PREALLOC) != 0;
+       sh_delalloc = (iflags & BMV_IF_DELALLOC) != 0;
 
        /*      If the BMV_IF_NO_DMAPI_READ interface bit specified, do not
         *      generate a DMAPI read event.  Otherwise, if the DM_EVENT_READ
@@ -5905,7 +5907,7 @@ xfs_getbmap(
 
        xfs_ilock(ip, XFS_IOLOCK_SHARED);
 
-       if (whichfork == XFS_DATA_FORK &&
+       if (!sh_delalloc && (whichfork == XFS_DATA_FORK) &&
                (ip->i_delayed_blks || ip->i_size > ip->i_d.di_size)) {
                /* xfs_fsize_t last_byte = xfs_file_last_byte(ip); */
                error = xfs_flush_pages(ip, (xfs_off_t)0,
@@ -5938,9 +5940,11 @@ xfs_getbmap(
 
        bmv->bmv_entries = 0;
 
-       if (XFS_IFORK_NEXTENTS(ip, whichfork) == 0) {
-               error = 0;
-               goto unlock_and_return;
+       if ((XFS_IFORK_NEXTENTS(ip, whichfork) == 0)) {
+               if (!sh_delalloc || whichfork == XFS_ATTR_FORK) {
+                       error = 0;
+                       goto unlock_and_return;
+               }
        }
 
        nexleft = nex;
@@ -5956,12 +5960,16 @@ xfs_getbmap(
                ASSERT(nmap <= subnex);
 
                for (i = 0; i < nmap && nexleft && bmv->bmv_length; i++) {
-                       out.bmv_oflags = (map[i].br_state == XFS_EXT_UNWRITTEN) 
?
-                                       BMV_OF_PREALLOC : 0;
+                       out.bmv_oflags = 0;
+                       if (map[i].br_state == XFS_EXT_UNWRITTEN)
+                               out.bmv_oflags |= BMV_OF_PREALLOC;
+                       else if (map[i].br_startblock == DELAYSTARTBLOCK)
+                               out.bmv_oflags |= BMV_OF_DELALLOC;
                        out.bmv_offset = XFS_FSB_TO_BB(mp, map[i].br_startoff);
                        out.bmv_length = XFS_FSB_TO_BB(mp, 
map[i].br_blockcount);
                        out.bmv_unused1 = out.bmv_unused2 = 0;
-                       ASSERT(map[i].br_startblock != DELAYSTARTBLOCK);
+                       ASSERT(sh_delalloc ||
+                             (map[i].br_startblock != DELAYSTARTBLOCK));
                         if (map[i].br_startblock == HOLESTARTBLOCK &&
                            whichfork == XFS_ATTR_FORK) {
                                /* came to the end of attribute fork */
Index: linux-2.6.27.x86_64/fs/xfs/xfs_fs.h
===================================================================
--- linux-2.6.27.x86_64.orig/fs/xfs/xfs_fs.h
+++ linux-2.6.27.x86_64/fs/xfs/xfs_fs.h
@@ -113,10 +113,13 @@ struct getbmapx {
 #define BMV_IF_ATTRFORK                0x1     /* return attr fork rather than 
data */
 #define BMV_IF_NO_DMAPI_READ   0x2     /* Do not generate DMAPI read event  */
 #define BMV_IF_PREALLOC                0x4     /* rtn status BMV_OF_PREALLOC 
if req */
-#define BMV_IF_VALID   (BMV_IF_ATTRFORK|BMV_IF_NO_DMAPI_READ|BMV_IF_PREALLOC)
+#define BMV_IF_DELALLOC                0x8     /* rtn status BMV_OF_DELALLOC 
if req */
+#define BMV_IF_VALID   \
+       (BMV_IF_ATTRFORK|BMV_IF_NO_DMAPI_READ|BMV_IF_PREALLOC|BMV_IF_DELALLOC)
 
 /*     bmv_oflags values - returned for for each non-header segment */
 #define BMV_OF_PREALLOC                0x1     /* segment = unwritten 
pre-allocation */
+#define BMV_OF_DELALLOC                0x2     /* segment = delayed allocation 
*/
 #define BMV_OF_LAST            0x4     /* segment is the last in the file */
 
 /*