e2fsck: optimize out the use region_t in scan_extent_node()

Since extents have a guarantee of being monotonically increasing we
merely need to check that block n+1 starts after block n.  This is a
simple enough check and we can perform this by calculating the next
expected logical block instead of using the region usage tracking data
abstraction.

Signed-off-by: Jaco Kroon <jaco@uls.co.za>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index 8044beed6ce161fbedcce9d32ed37e291a201bcb..bc26beb99f6a23f531a2c01e9ca4f7ac71789e9a 100644 (file)
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -96,7 +96,7 @@ struct process_block_struct {
        struct problem_context *pctx;
        ext2fs_block_bitmap fs_meta_blocks;
        e2fsck_t        ctx;
-       region_t        region;
+       blk64_t         next_lblock;
        struct extent_tree_info eti;
 };
 
@@ -2628,9 +2628,18 @@ static void scan_extent_node(e2fsck_t ctx, struct problem_context *pctx,
                          (1U << (21 - ctx->fs->super->s_log_block_size))))
                        problem = PR_1_TOOBIG_DIR;
 
-               if (is_leaf && problem == 0 && extent.e_len > 0 &&
-                   region_allocate(pb->region, extent.e_lblk, extent.e_len))
-                       problem = PR_1_EXTENT_COLLISION;
+               if (is_leaf && problem == 0 && extent.e_len > 0) {
+#if 0
+                       printf("extent_region(ino=%u, expect=%llu, "
+                              "lblk=%llu, len=%u)\n",
+                              pb->ino, pb->next_lblock,
+                              extent.e_lblk, extent.e_len);
+#endif
+                       if (extent.e_lblk < pb->next_lblock)
+                               problem = PR_1_EXTENT_COLLISION;
+                       else if (extent.e_lblk + extent.e_len > pb->next_lblock)
+                               pb->next_lblock = extent.e_lblk + extent.e_len;
+               }
 
                /*
                 * Uninitialized blocks in a directory?  Clear the flag and
@@ -2963,13 +2972,7 @@ static void check_blocks_extents(e2fsck_t ctx, struct problem_context *pctx,
        memset(pb->eti.ext_info, 0, sizeof(pb->eti.ext_info));
        pb->eti.ino = pb->ino;
 
-       pb->region = region_create(0, info.max_lblk);
-       if (!pb->region) {
-               ext2fs_extent_free(ehandle);
-               fix_problem(ctx, PR_1_EXTENT_ALLOC_REGION_ABORT, pctx);
-               ctx->flags |= E2F_FLAG_ABORT;
-               return;
-       }
+       pb->next_lblock = 0;
 
        eof_lblk = ((EXT2_I_SIZE(inode) + fs->blocksize - 1) >>
                EXT2_BLOCK_SIZE_BITS(fs->super)) - 1;
@@ -2982,8 +2985,6 @@ static void check_blocks_extents(e2fsck_t ctx, struct problem_context *pctx,
                                   "check_blocks_extents");
                pctx->errcode = 0;
        }
-       region_free(pb->region);
-       pb->region = NULL;
        ext2fs_extent_free(ehandle);
 
        /* Rebuild unless it's a dir and we're rehashing it */