[XFS] fix uninitialised variable bug in dquot release.

gcc is warning about an uninitialised variable in xfs_growfs_rt().
This is a false positive. Fix it by changing the scope of the
transaction pointer to wholly within the internal loop inside
the function.

While there, preemptively change xfs_growfs_rt_alloc() in the
same way as it has exactly the same structure as xfs_growfs_rt()
but gcc is not warning about it. Yet.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Niv Sardi <xaiki@sgi.com>

1 files changed, 18 insertions, 21 deletions

diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index e2f68de16159..f18b9b281799 100644
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c
@@ -85,7 +85,6 @@ xfs_growfs_rt_alloc(
 {
         xfs_fileoff_t   bno;            /* block number in file */
         xfs_buf_t       *bp;            /* temporary buffer for zeroing */
-        int             cancelflags;    /* flags for xfs_trans_cancel */
         int             committed;      /* transaction committed flag */
         xfs_daddr_t     d;              /* disk block address */
         int             error;          /* error return value */
@@ -96,15 +95,16 @@ xfs_growfs_rt_alloc(
         xfs_bmbt_irec_t map;            /* block map output */
         int             nmap;           /* number of block maps */
         int             resblks;        /* space reservation */
-        xfs_trans_t     *tp;            /* transaction pointer */
 
         /*
          * Allocate space to the file, as necessary.
          */
         while (oblocks < nblocks) {
+                int             cancelflags = 0;
+                xfs_trans_t     *tp;
+
                 tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFSRT_ALLOC);
                 resblks = XFS_GROWFSRT_SPACE_RES(mp, nblocks - oblocks);
-                cancelflags = 0;
                 /*
                  * Reserve space & log for one extent added to the file.
                  */
@@ -171,7 +171,9 @@ xfs_growfs_rt_alloc(
                                 mp->m_bsize, 0);
                         if (bp == NULL) {
                                 error = XFS_ERROR(EIO);
-                                goto error_cancel;
+error_cancel:
+                                xfs_trans_cancel(tp, cancelflags);
+                                goto error;
                         }
                         memset(XFS_BUF_PTR(bp), 0, mp->m_sb.sb_blocksize);
                         xfs_trans_log_buf(tp, bp, 0, mp->m_sb.sb_blocksize - 1);
@@ -188,8 +190,6 @@ xfs_growfs_rt_alloc(
                 oblocks = map.br_startoff + map.br_blockcount;
         }
         return 0;
-error_cancel:
-        xfs_trans_cancel(tp, cancelflags);
 error:
         return error;
 }
@@ -1856,7 +1856,6 @@ xfs_growfs_rt(
 {
         xfs_rtblock_t   bmbno;          /* bitmap block number */
         xfs_buf_t       *bp;            /* temporary buffer */
-        int             cancelflags;    /* flags for xfs_trans_cancel */
         int             error;          /* error return value */
         xfs_inode_t     *ip;            /* bitmap inode, used as lock */
         xfs_mount_t     *nmp;           /* new (fake) mount structure */
@@ -1872,10 +1871,8 @@ xfs_growfs_rt(
         xfs_extlen_t    rsumblocks;     /* current number of rt summary blks */
         xfs_sb_t        *sbp;           /* old superblock */
         xfs_fsblock_t   sumbno;         /* summary block number */
-        xfs_trans_t     *tp;            /* transaction pointer */
 
         sbp = &mp->m_sb;
-        cancelflags = 0;
         /*
          * Initial error checking.
          */
@@ -1942,6 +1939,9 @@ xfs_growfs_rt(
                      ((sbp->sb_rextents & ((1 << mp->m_blkbit_log) - 1)) != 0);
              bmbno < nrbmblocks;
              bmbno++) {
+                xfs_trans_t     *tp;
+                int             cancelflags = 0;
+
                 *nmp = *mp;
                 nsbp = &nmp->m_sb;
                 /*
@@ -1967,16 +1967,15 @@ xfs_growfs_rt(
                  * Start a transaction, get the log reservation.
                  */
                 tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFSRT_FREE);
-                cancelflags = 0;
                 if ((error = xfs_trans_reserve(tp, 0,
                                 XFS_GROWRTFREE_LOG_RES(nmp), 0, 0, 0)))
-                        break;
+                        goto error_cancel;
                 /*
                  * Lock out other callers by grabbing the bitmap inode lock.
                  */
                 if ((error = xfs_trans_iget(mp, tp, mp->m_sb.sb_rbmino, 0,
                                                 XFS_ILOCK_EXCL, &ip)))
-                        break;
+                        goto error_cancel;
                 ASSERT(ip == mp->m_rbmip);
                 /*
                  * Update the bitmap inode's size.
@@ -1990,7 +1989,7 @@ xfs_growfs_rt(
                  */
                 if ((error = xfs_trans_iget(mp, tp, mp->m_sb.sb_rsumino, 0,
                                                 XFS_ILOCK_EXCL, &ip)))
-                        break;
+                        goto error_cancel;
                 ASSERT(ip == mp->m_rsumip);
                 /*
                  * Update the summary inode's size.
@@ -2005,7 +2004,7 @@ xfs_growfs_rt(
                     mp->m_rsumlevels != nmp->m_rsumlevels) {
                         error = xfs_rtcopy_summary(mp, nmp, tp);
                         if (error)
-                                break;
+                                goto error_cancel;
                 }
                 /*
                  * Update superblock fields.
@@ -2031,8 +2030,11 @@ xfs_growfs_rt(
                 bp = NULL;
                 error = xfs_rtfree_range(nmp, tp, sbp->sb_rextents,
                         nsbp->sb_rextents - sbp->sb_rextents, &bp, &sumbno);
-                if (error)
+                if (error) {
+error_cancel:
+                        xfs_trans_cancel(tp, cancelflags);
                         break;
+                }
                 /*
                  * Mark more blocks free in the superblock.
                  */
@@ -2045,15 +2047,10 @@ xfs_growfs_rt(
                 mp->m_rsumsize = nrsumsize;
 
                 error = xfs_trans_commit(tp, 0);
-                if (error) {
-                        tp = NULL;
+                if (error)
                         break;
-                }
         }
 
-        if (error && tp)
-                xfs_trans_cancel(tp, cancelflags);
-
         /*
          * Free the fake mp structure.
          */