[XFS] Dynamically allocate xfs_dir2_put_args_t structure to reduce stack

pressure in xfs_dir2_leaf_getdents routine.

SGI-PV: 947312
SGI-Modid: xfs-linux-melb:xfs-kern:25359a

Signed-off-by: Nathan Scott <nathans@sgi.com>

diff --git a/fs/xfs/xfs_dir2_leaf.c b/fs/xfs/xfs_dir2_leaf.c
index d342b6b..e4e07c8 100644 (file)
--- a/fs/xfs/xfs_dir2_leaf.c
+++ b/fs/xfs/xfs_dir2_leaf.c
@@ -766,7 +766,7 @@ xfs_dir2_leaf_getdents(
        xfs_dir2_data_entry_t   *dep;           /* data entry */
        xfs_dir2_data_unused_t  *dup;           /* unused entry */
        int                     eof;            /* reached end of directory */
-       int                     error=0;                /* error return value */
+       int                     error = 0;      /* error return value */
        int                     i;              /* temporary loop index */
        int                     j;              /* temporary loop index */
        int                     length;         /* temporary length value */
@@ -778,8 +778,8 @@ xfs_dir2_leaf_getdents(
        xfs_mount_t             *mp;            /* filesystem mount point */
        xfs_dir2_off_t          newoff;         /* new curoff after new blk */
        int                     nmap;           /* mappings to ask xfs_bmapi */
-       xfs_dir2_put_args_t     p;              /* formatting arg bundle */
-       char                    *ptr=NULL;              /* pointer to current data */
+       xfs_dir2_put_args_t     *p;             /* formatting arg bundle */
+       char                    *ptr = NULL;    /* pointer to current data */
        int                     ra_current;     /* number of read-ahead blks */
        int                     ra_index;       /* *map index for read-ahead */
        int                     ra_offset;      /* map entry offset for ra */
@@ -797,9 +797,10 @@ xfs_dir2_leaf_getdents(
        /*
         * Setup formatting arguments.
         */
-       p.dbp = dbp;
-       p.put = put;
-       p.uio = uio;
+       p = kmem_alloc(sizeof(*p), KM_SLEEP);
+       p->dbp = dbp;
+       p->put = put;
+       p->uio = uio;
        /*
         * Set up to bmap a number of blocks based on the caller's
         * buffer size, the directory block size, and the filesystem
@@ -1092,24 +1093,24 @@ xfs_dir2_leaf_getdents(
                 */
                dep = (xfs_dir2_data_entry_t *)ptr;
 
-               p.namelen = dep->namelen;
+               p->namelen = dep->namelen;
 
-               length = XFS_DIR2_DATA_ENTSIZE(p.namelen);
+               length = XFS_DIR2_DATA_ENTSIZE(p->namelen);
 
-               p.cook = XFS_DIR2_BYTE_TO_DATAPTR(mp, curoff + length);
+               p->cook = XFS_DIR2_BYTE_TO_DATAPTR(mp, curoff + length);
 
-               p.ino = INT_GET(dep->inumber, ARCH_CONVERT);
+               p->ino = INT_GET(dep->inumber, ARCH_CONVERT);
 #if XFS_BIG_INUMS
-               p.ino += mp->m_inoadd;
+               p->ino += mp->m_inoadd;
 #endif
-               p.name = (char *)dep->name;
+               p->name = (char *)dep->name;
 
-               error = p.put(&p);
+               error = p->put(p);
 
                /*
                 * Won't fit.  Return to caller.
                 */
-               if (!p.done) {
+               if (!p->done) {
                        eof = 0;
                        break;
                }
@@ -1129,6 +1130,7 @@ xfs_dir2_leaf_getdents(
        else
                uio->uio_offset = XFS_DIR2_BYTE_TO_DATAPTR(mp, curoff);
        kmem_free(map, map_size * sizeof(*map));
+       kmem_free(p, sizeof(*p));
        if (bp)
                xfs_da_brelse(tp, bp);
        return error;