xfs: refactor xfs_bmap_add_extent_unwritten_real

Source kernel commit: 79fa6143a939a6b50d1d9dc736336e57d06b849d

Use xfs_iext_get_extent to find, and xfs_iext_update_extent to update
entries in the in-core extent list.  This isolates the function from
the detailed layout of the extent list, and generally makes the code
a lot more readable.

Also get rid of the oldext and newext variables as using the extent
records is a lot more descriptive.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

diff --git a/libxfs/xfs_bmap.c b/libxfs/xfs_bmap.c
index 0c4a839d7de4bad33c2f8e123c1e7ae3ed66390c..7bf90ab25ec440e0d2ca43f773349050a6133054 100644 (file)
--- a/libxfs/xfs_bmap.c
+++ b/libxfs/xfs_bmap.c
@@ -2134,18 +2134,16 @@ xfs_bmap_add_extent_unwritten_real(
        int                     *logflagsp) /* inode logging flags */
 {
        xfs_btree_cur_t         *cur;   /* btree cursor */
-       xfs_bmbt_rec_host_t     *ep;    /* extent entry for idx */
        int                     error;  /* error return value */
        int                     i;      /* temp state */
        xfs_ifork_t             *ifp;   /* inode fork pointer */
        xfs_fileoff_t           new_endoff;     /* end offset of new entry */
-       xfs_exntst_t            newext; /* new extent state */
-       xfs_exntst_t            oldext; /* old extent state */
        xfs_bmbt_irec_t         r[3];   /* neighbor extent entries */
                                        /* left is 0, right is 1, prev is 2 */
        int                     rval=0; /* return value (logging flags) */
        int                     state = 0;/* state bits, accessed thru macros */
        struct xfs_mount        *mp = ip->i_mount;
+       struct xfs_bmbt_irec    old;
 
        *logflagsp = 0;
 
@@ -2168,12 +2166,8 @@ xfs_bmap_add_extent_unwritten_real(
         * Set up a bunch of variables to make the tests simpler.
         */
        error = 0;
-       ep = xfs_iext_get_ext(ifp, *idx);
-       xfs_bmbt_get_all(ep, &PREV);
-       newext = new->br_state;
-       oldext = (newext == XFS_EXT_UNWRITTEN) ?
-               XFS_EXT_NORM : XFS_EXT_UNWRITTEN;
-       ASSERT(PREV.br_state == oldext);
+       xfs_iext_get_extent(ifp, *idx, &PREV);
+       ASSERT(new->br_state != PREV.br_state);
        new_endoff = new->br_startoff + new->br_blockcount;
        ASSERT(PREV.br_startoff <= new->br_startoff);
        ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);
@@ -2202,7 +2196,7 @@ xfs_bmap_add_extent_unwritten_real(
        if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
            LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
            LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
-           LEFT.br_state == newext &&
+           LEFT.br_state == new->br_state &&
            LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN)
                state |= BMAP_LEFT_CONTIG;
 
@@ -2221,7 +2215,7 @@ xfs_bmap_add_extent_unwritten_real(
        if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
            new_endoff == RIGHT.br_startoff &&
            new->br_startblock + new->br_blockcount == RIGHT.br_startblock &&
-           newext == RIGHT.br_state &&
+           new->br_state == RIGHT.br_state &&
            new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN &&
            ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
                       BMAP_RIGHT_FILLING)) !=
@@ -2245,9 +2239,8 @@ xfs_bmap_add_extent_unwritten_real(
                --*idx;
 
                trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
-               xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx),
-                       LEFT.br_blockcount + PREV.br_blockcount +
-                       RIGHT.br_blockcount);
+               LEFT.br_blockcount += PREV.br_blockcount + RIGHT.br_blockcount;
+               xfs_iext_update_extent(ifp, *idx, &LEFT);
                trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
                xfs_iext_remove(ip, *idx + 1, 2, state);
@@ -2274,10 +2267,10 @@ xfs_bmap_add_extent_unwritten_real(
                        if ((error = xfs_btree_decrement(cur, 0, &i)))
                                goto done;
                        XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
-                       if ((error = xfs_bmbt_update(cur, LEFT.br_startoff,
-                               LEFT.br_startblock,
-                               LEFT.br_blockcount + PREV.br_blockcount +
-                               RIGHT.br_blockcount, LEFT.br_state)))
+                       error = xfs_bmbt_update(cur, LEFT.br_startoff,
+                                       LEFT.br_startblock, LEFT.br_blockcount,
+                                       LEFT.br_state);
+                       if (error)
                                goto done;
                }
                break;
@@ -2290,8 +2283,8 @@ xfs_bmap_add_extent_unwritten_real(
                --*idx;
 
                trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
-               xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx),
-                       LEFT.br_blockcount + PREV.br_blockcount);
+               LEFT.br_blockcount += PREV.br_blockcount;
+               xfs_iext_update_extent(ifp, *idx, &LEFT);
                trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
                xfs_iext_remove(ip, *idx + 1, 1, state);
@@ -2312,10 +2305,10 @@ xfs_bmap_add_extent_unwritten_real(
                        if ((error = xfs_btree_decrement(cur, 0, &i)))
                                goto done;
                        XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
-                       if ((error = xfs_bmbt_update(cur, LEFT.br_startoff,
-                               LEFT.br_startblock,
-                               LEFT.br_blockcount + PREV.br_blockcount,
-                               LEFT.br_state)))
+                       error = xfs_bmbt_update(cur, LEFT.br_startoff,
+                                       LEFT.br_startblock, LEFT.br_blockcount,
+                                       LEFT.br_state);
+                       if (error)
                                goto done;
                }
                break;
@@ -2326,10 +2319,11 @@ xfs_bmap_add_extent_unwritten_real(
                 * The right neighbor is contiguous, the left is not.
                 */
                trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
-               xfs_bmbt_set_blockcount(ep,
-                       PREV.br_blockcount + RIGHT.br_blockcount);
-               xfs_bmbt_set_state(ep, newext);
+               PREV.br_blockcount += RIGHT.br_blockcount;
+               PREV.br_state = new->br_state;
+               xfs_iext_update_extent(ifp, *idx, &PREV);
                trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
+
                xfs_iext_remove(ip, *idx + 1, 1, state);
                XFS_IFORK_NEXT_SET(ip, whichfork,
                                XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
@@ -2348,10 +2342,10 @@ xfs_bmap_add_extent_unwritten_real(
                        if ((error = xfs_btree_decrement(cur, 0, &i)))
                                goto done;
                        XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
-                       if ((error = xfs_bmbt_update(cur, new->br_startoff,
-                               new->br_startblock,
-                               new->br_blockcount + RIGHT.br_blockcount,
-                               newext)))
+                       error = xfs_bmbt_update(cur, PREV.br_startoff,
+                                       PREV.br_startblock, PREV.br_blockcount,
+                                       PREV.br_state);
+                       if (error)
                                goto done;
                }
                break;
@@ -2363,7 +2357,8 @@ xfs_bmap_add_extent_unwritten_real(
                 * the new one.
                 */
                trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
-               xfs_bmbt_set_state(ep, newext);
+               PREV.br_state = new->br_state;
+               xfs_iext_update_extent(ifp, *idx, &PREV);
                trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
                if (cur == NULL)
@@ -2375,9 +2370,10 @@ xfs_bmap_add_extent_unwritten_real(
                                        &i)))
                                goto done;
                        XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
-                       if ((error = xfs_bmbt_update(cur, new->br_startoff,
-                               new->br_startblock, new->br_blockcount,
-                               newext)))
+                       error = xfs_bmbt_update(cur, PREV.br_startoff,
+                                       PREV.br_startblock, PREV.br_blockcount,
+                                       PREV.br_state);
+                       if (error)
                                goto done;
                }
                break;
@@ -2388,17 +2384,16 @@ xfs_bmap_add_extent_unwritten_real(
                 * The left neighbor is contiguous.
                 */
                trace_xfs_bmap_pre_update(ip, *idx - 1, state, _THIS_IP_);
-               xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx - 1),
-                       LEFT.br_blockcount + new->br_blockcount);
-               xfs_bmbt_set_startoff(ep,
-                       PREV.br_startoff + new->br_blockcount);
+               LEFT.br_blockcount += new->br_blockcount;
+               xfs_iext_update_extent(ifp, *idx - 1, &LEFT);
                trace_xfs_bmap_post_update(ip, *idx - 1, state, _THIS_IP_);
 
+               old = PREV;
                trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
-               xfs_bmbt_set_startblock(ep,
-                       new->br_startblock + new->br_blockcount);
-               xfs_bmbt_set_blockcount(ep,
-                       PREV.br_blockcount - new->br_blockcount);
+               PREV.br_startoff += new->br_blockcount;
+               PREV.br_startblock += new->br_blockcount;
+               PREV.br_blockcount -= new->br_blockcount;
+               xfs_iext_update_extent(ifp, *idx, &PREV);
                trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
                --*idx;
@@ -2407,23 +2402,23 @@ xfs_bmap_add_extent_unwritten_real(
                        rval = XFS_ILOG_DEXT;
                else {
                        rval = 0;
-                       if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
-                                       PREV.br_startblock, PREV.br_blockcount,
-                                       &i)))
+                       error = xfs_bmbt_lookup_eq(cur, old.br_startoff,
+                                       old.br_startblock, old.br_blockcount,
+                                       &i);
+                       if (error)
                                goto done;
                        XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
-                       if ((error = xfs_bmbt_update(cur,
-                               PREV.br_startoff + new->br_blockcount,
-                               PREV.br_startblock + new->br_blockcount,
-                               PREV.br_blockcount - new->br_blockcount,
-                               oldext)))
+                       error = xfs_bmbt_update(cur, PREV.br_startoff,
+                                       PREV.br_startblock, PREV.br_blockcount,
+                                       PREV.br_state);
+                       if (error)
                                goto done;
-                       if ((error = xfs_btree_decrement(cur, 0, &i)))
+                       error = xfs_btree_decrement(cur, 0, &i);
+                       if (error)
                                goto done;
                        error = xfs_bmbt_update(cur, LEFT.br_startoff,
-                               LEFT.br_startblock,
-                               LEFT.br_blockcount + new->br_blockcount,
-                               LEFT.br_state);
+                                       LEFT.br_startblock, LEFT.br_blockcount,
+                                       LEFT.br_state);
                        if (error)
                                goto done;
                }
@@ -2434,13 +2429,12 @@ xfs_bmap_add_extent_unwritten_real(
                 * Setting the first part of a previous oldext extent to newext.
                 * The left neighbor is not contiguous.
                 */
+               old = PREV;
                trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
-               ASSERT(ep && xfs_bmbt_get_state(ep) == oldext);
-               xfs_bmbt_set_startoff(ep, new_endoff);
-               xfs_bmbt_set_blockcount(ep,
-                       PREV.br_blockcount - new->br_blockcount);
-               xfs_bmbt_set_startblock(ep,
-                       new->br_startblock + new->br_blockcount);
+               PREV.br_startoff += new->br_blockcount;
+               PREV.br_startblock += new->br_blockcount;
+               PREV.br_blockcount -= new->br_blockcount;
+               xfs_iext_update_extent(ifp, *idx, &PREV);
                trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
                xfs_iext_insert(ip, *idx, 1, new, state);
@@ -2450,16 +2444,16 @@ xfs_bmap_add_extent_unwritten_real(
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
-                       if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
-                                       PREV.br_startblock, PREV.br_blockcount,
-                                       &i)))
+                       error = xfs_bmbt_lookup_eq(cur, old.br_startoff,
+                                       old.br_startblock, old.br_blockcount,
+                                       &i);
+                       if (error)
                                goto done;
                        XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
-                       if ((error = xfs_bmbt_update(cur,
-                               PREV.br_startoff + new->br_blockcount,
-                               PREV.br_startblock + new->br_blockcount,
-                               PREV.br_blockcount - new->br_blockcount,
-                               oldext)))
+                       error = xfs_bmbt_update(cur, PREV.br_startoff,
+                                       PREV.br_startblock, PREV.br_blockcount,
+                                       PREV.br_state);
+                       if (error)
                                goto done;
                        cur->bc_rec.b = *new;
                        if ((error = xfs_btree_insert(cur, &i)))
@@ -2473,39 +2467,43 @@ xfs_bmap_add_extent_unwritten_real(
                 * Setting the last part of a previous oldext extent to newext.
                 * The right neighbor is contiguous with the new allocation.
                 */
+               old = PREV;
                trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
-               xfs_bmbt_set_blockcount(ep,
-                       PREV.br_blockcount - new->br_blockcount);
+               PREV.br_blockcount -= new->br_blockcount;
+               xfs_iext_update_extent(ifp, *idx, &PREV);
                trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
                ++*idx;
 
                trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
-               xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, *idx),
-                       new->br_startoff, new->br_startblock,
-                       new->br_blockcount + RIGHT.br_blockcount, newext);
+               RIGHT.br_startoff = new->br_startoff;
+               RIGHT.br_startblock = new->br_startblock;
+               RIGHT.br_blockcount += new->br_blockcount;
+               xfs_iext_update_extent(ifp, *idx, &RIGHT);
                trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
                if (cur == NULL)
                        rval = XFS_ILOG_DEXT;
                else {
                        rval = 0;
-                       if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
-                                       PREV.br_startblock,
-                                       PREV.br_blockcount, &i)))
+                       error = xfs_bmbt_lookup_eq(cur, old.br_startoff,
+                                       old.br_startblock, old.br_blockcount,
+                                       &i);
+                       if (error)
                                goto done;
                        XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
-                       if ((error = xfs_bmbt_update(cur, PREV.br_startoff,
-                               PREV.br_startblock,
-                               PREV.br_blockcount - new->br_blockcount,
-                               oldext)))
+                       error = xfs_bmbt_update(cur, PREV.br_startoff,
+                                       PREV.br_startblock, PREV.br_blockcount,
+                                       PREV.br_state);
+                       if (error)
                                goto done;
-                       if ((error = xfs_btree_increment(cur, 0, &i)))
+                       error = xfs_btree_increment(cur, 0, &i);
+                       if (error)
                                goto done;
-                       if ((error = xfs_bmbt_update(cur, new->br_startoff,
-                               new->br_startblock,
-                               new->br_blockcount + RIGHT.br_blockcount,
-                               newext)))
+                       error = xfs_bmbt_update(cur, RIGHT.br_startoff,
+                                       RIGHT.br_startblock,
+                                       RIGHT.br_blockcount, RIGHT.br_state);
+                       if (error)
                                goto done;
                }
                break;
@@ -2515,9 +2513,10 @@ xfs_bmap_add_extent_unwritten_real(
                 * Setting the last part of a previous oldext extent to newext.
                 * The right neighbor is not contiguous.
                 */
+               old = PREV;
                trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
-               xfs_bmbt_set_blockcount(ep,
-                       PREV.br_blockcount - new->br_blockcount);
+               PREV.br_blockcount -= new->br_blockcount;
+               xfs_iext_update_extent(ifp, *idx, &PREV);
                trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
                ++*idx;
@@ -2529,15 +2528,16 @@ xfs_bmap_add_extent_unwritten_real(
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
-                       if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
-                                       PREV.br_startblock, PREV.br_blockcount,
-                                       &i)))
+                       error = xfs_bmbt_lookup_eq(cur, old.br_startoff,
+                                       old.br_startblock, old.br_blockcount,
+                                       &i);
+                       if (error)
                                goto done;
                        XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
-                       if ((error = xfs_bmbt_update(cur, PREV.br_startoff,
-                               PREV.br_startblock,
-                               PREV.br_blockcount - new->br_blockcount,
-                               oldext)))
+                       error = xfs_bmbt_update(cur, PREV.br_startoff,
+                                       PREV.br_startblock, PREV.br_blockcount,
+                                       PREV.br_state);
+                       if (error)
                                goto done;
                        if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
                                        new->br_startblock, new->br_blockcount,
@@ -2557,17 +2557,18 @@ xfs_bmap_add_extent_unwritten_real(
                 * newext.  Contiguity is impossible here.
                 * One extent becomes three extents.
                 */
+               old = PREV;
                trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
-               xfs_bmbt_set_blockcount(ep,
-                       new->br_startoff - PREV.br_startoff);
+               PREV.br_blockcount = new->br_startoff - PREV.br_startoff;
+               xfs_iext_update_extent(ifp, *idx, &PREV);
                trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
                r[0] = *new;
                r[1].br_startoff = new_endoff;
                r[1].br_blockcount =
-                       PREV.br_startoff + PREV.br_blockcount - new_endoff;
+                       old.br_startoff + old.br_blockcount - new_endoff;
                r[1].br_startblock = new->br_startblock + new->br_blockcount;
-               r[1].br_state = oldext;
+               r[1].br_state = PREV.br_state;
 
                ++*idx;
                xfs_iext_insert(ip, *idx, 2, &r[0], state);
@@ -2578,9 +2579,10 @@ xfs_bmap_add_extent_unwritten_real(
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
-                       if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
-                                       PREV.br_startblock, PREV.br_blockcount,
-                                       &i)))
+                       error = xfs_bmbt_lookup_eq(cur, old.br_startoff,
+                                       old.br_startblock, old.br_blockcount,
+                                       &i);
+                       if (error)
                                goto done;
                        XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
                        /* new right extent - oldext */
@@ -2590,8 +2592,6 @@ xfs_bmap_add_extent_unwritten_real(
                                goto done;
                        /* new left extent - oldext */
                        cur->bc_rec.b = PREV;
-                       cur->bc_rec.b.br_blockcount =
-                               new->br_startoff - PREV.br_startoff;
                        if ((error = xfs_btree_insert(cur, &i)))
                                goto done;
                        XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);