xfs: reorganize xfs_iomap_prealloc_size to remove indentation

The majority of xfs_iomap_prealloc_size() executes within the
check for lack of default I/O size. Reverse the logic to remove the
extra indentation.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

1 files changed, 32 insertions, 31 deletions

diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index c8cb337efccf..344557eef928 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -381,42 +381,43 @@ xfs_iomap_prealloc_size(
         int                     nimaps)
 {
         xfs_fsblock_t           alloc_blocks = 0;
+        int                     shift = 0;
+        int64_t                 freesp;
 
         alloc_blocks = xfs_iomap_eof_prealloc_initial_size(mp, ip, offset,
                                                            imap, nimaps);
-        if (alloc_blocks > 0) {
-                int shift = 0;
-                int64_t freesp;
-
-                alloc_blocks = XFS_FILEOFF_MIN(MAXEXTLEN,
-                                        rounddown_pow_of_two(alloc_blocks));
-
-                xfs_icsb_sync_counters(mp, XFS_ICSB_LAZY_COUNT);
-                freesp = mp->m_sb.sb_fdblocks;
-                if (freesp < mp->m_low_space[XFS_LOWSP_5_PCNT]) {
-                        shift = 2;
-                        if (freesp < mp->m_low_space[XFS_LOWSP_4_PCNT])
-                                shift++;
-                        if (freesp < mp->m_low_space[XFS_LOWSP_3_PCNT])
-                                shift++;
-                        if (freesp < mp->m_low_space[XFS_LOWSP_2_PCNT])
-                                shift++;
-                        if (freesp < mp->m_low_space[XFS_LOWSP_1_PCNT])
-                                shift++;
-                }
-                if (shift)
-                        alloc_blocks >>= shift;
-
-                /*
-                 * If we are still trying to allocate more space than is
-                 * available, squash the prealloc hard. This can happen if we
-                 * have a large file on a small filesystem and the above
-                 * lowspace thresholds are smaller than MAXEXTLEN.
-                 */
-                while (alloc_blocks && alloc_blocks >= freesp)
-                        alloc_blocks >>= 4;
+        if (!alloc_blocks)
+                goto check_writeio;
+
+        alloc_blocks = XFS_FILEOFF_MIN(MAXEXTLEN,
+                                rounddown_pow_of_two(alloc_blocks));
+
+        xfs_icsb_sync_counters(mp, XFS_ICSB_LAZY_COUNT);
+        freesp = mp->m_sb.sb_fdblocks;
+        if (freesp < mp->m_low_space[XFS_LOWSP_5_PCNT]) {
+                shift = 2;
+                if (freesp < mp->m_low_space[XFS_LOWSP_4_PCNT])
+                        shift++;
+                if (freesp < mp->m_low_space[XFS_LOWSP_3_PCNT])
+                        shift++;
+                if (freesp < mp->m_low_space[XFS_LOWSP_2_PCNT])
+                        shift++;
+                if (freesp < mp->m_low_space[XFS_LOWSP_1_PCNT])
+                        shift++;
         }
+        if (shift)
+                alloc_blocks >>= shift;
+
+        /*
+         * If we are still trying to allocate more space than is
+         * available, squash the prealloc hard. This can happen if we
+         * have a large file on a small filesystem and the above
+         * lowspace thresholds are smaller than MAXEXTLEN.
+         */
+        while (alloc_blocks && alloc_blocks >= freesp)
+                alloc_blocks >>= 4;
 
+check_writeio:
         if (alloc_blocks < mp->m_writeio_blocks)
                 alloc_blocks = mp->m_writeio_blocks;