LU-6489 osd-ldiskfs: check max_page_index correctly

This patch fixes a issue that original code check
max_page_index against incorrect variable.

Signed-off-by: Yang Sheng <yang.sheng@intel.com>
Change-Id: I4b164d6187ef4a1c343d4b5803b8915283394037
Reviewed-on: http://review.whamcloud.com/14731
Tested-by: Jenkins
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/lustre/osd-ldiskfs/osd_io.c b/lustre/osd-ldiskfs/osd_io.c
index 8507c38..3657495 100644 (file)
--- a/lustre/osd-ldiskfs/osd_io.c
+++ b/lustre/osd-ldiskfs/osd_io.c
@@ -763,23 +763,26 @@ map:
        return err;
 }
 
-static int osd_ldiskfs_map_nblocks(struct inode *inode, unsigned long block,
-                                  unsigned long num, sector_t *blocks,
-                                  int create)
+static int osd_ldiskfs_map_nblocks(struct inode *inode, unsigned long index,
+                                  int clen, sector_t *blocks, int create)
 {
+       int blocks_per_page = PAGE_CACHE_SIZE >> inode->i_blkbits;
        struct bpointers bp;
        int err;
 
-       CDEBUG(D_OTHER, "blocks %lu-%lu requested for inode %u\n",
-              block, block + num - 1, (unsigned) inode->i_ino);
+       if (index + clen >= inode->i_sb->s_maxbytes >> PAGE_SHIFT)
+               return -EFBIG;
 
        bp.blocks = blocks;
-       bp.start = block;
-       bp.init_num = bp.num = num;
+       bp.start = index * blocks_per_page;
+       bp.init_num = bp.num = clen * blocks_per_page;
        bp.create = create;
 
-       err = ldiskfs_ext_walk_space(inode, block, num,
-                                        ldiskfs_ext_new_extent_cb, &bp);
+       CDEBUG(D_OTHER, "blocks %lu-%lu requested for inode %u\n",
+              bp.start, bp.start + bp.num - 1, (unsigned)inode->i_ino);
+
+       err = ldiskfs_ext_walk_space(inode, bp.start, bp.num,
+                                    ldiskfs_ext_new_extent_cb, &bp);
        ldiskfs_ext_invalidate_cache(inode);
 
        return err;
@@ -818,13 +821,8 @@ static int osd_ldiskfs_map_ext_inode_pages(struct inode *inode,
                                           int pages, sector_t *blocks,
                                           int create)
 {
-       int blocks_per_page = PAGE_CACHE_SIZE >> inode->i_blkbits;
-       int rc = 0, i = 0;
+       int rc = 0, i = 0, clen = 0;
        struct page *fp = NULL;
-       int clen = 0;
-       pgoff_t extent_max_page_index;
-
-       extent_max_page_index = inode->i_sb->s_maxbytes >> PAGE_SHIFT;
 
        CDEBUG(D_OTHER, "inode %lu: map %d pages from %lu\n",
                inode->i_ino, pages, (*page)->index);
@@ -846,25 +844,21 @@ static int osd_ldiskfs_map_ext_inode_pages(struct inode *inode,
                        continue;
                }
 
-               if (fp->index + i >= extent_max_page_index)
-                       GOTO(cleanup, rc = -EFBIG);
-
                /* process found extent */
-               rc = osd_ldiskfs_map_nblocks(inode, fp->index * blocks_per_page,
-                                            clen * blocks_per_page, blocks,
-                                            create);
+               rc = osd_ldiskfs_map_nblocks(inode, fp->index, clen,
+                                            blocks, create);
                if (rc)
                        GOTO(cleanup, rc);
 
                /* look for next extent */
                fp = NULL;
-               blocks += blocks_per_page * clen;
+               blocks += clen * (PAGE_CACHE_SIZE >> inode->i_blkbits);
        }
 
        if (fp)
-               rc = osd_ldiskfs_map_nblocks(inode, fp->index * blocks_per_page,
-                                            clen * blocks_per_page, blocks,
-                                            create);
+               rc = osd_ldiskfs_map_nblocks(inode, fp->index, clen,
+                                            blocks, create);
+
 cleanup:
        return rc;
 }
@@ -919,7 +913,7 @@ static int osd_ldiskfs_map_inode_pages(struct inode *inode, struct page **page,
                        if (++i != pages)
                                continue;
                }
-               if (fp->index + i >= max_page_index)
+               if (fp->index + clen >= max_page_index)
                        GOTO(cleanup, rc = -EFBIG);
                /* process found extent */
                map.m_lblk = fp->index * blocks_per_page;