Changeset 8a45707d in mainline

Timestamp:

2015-09-18T15:08:40Z (9 years ago)

Author:

Martin Decky <martin@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

d6c98451

Parents:

c354a08

Message:

avoid the corner case where the last block group is the only block group with free blocks, but it has lower than average number of free inodes
(this bug rendered the rest of the free blocks on the file system unusable for new inodes)

File:

• uspace/lib/ext4/libext4_ialloc.c (modified) (1 diff)

uspace/lib/ext4/libext4_ialloc.c

@@ -195 +195 @@
                 uint32_t used_dirs = ext4_block_group_get_used_dirs_count(bg, sb);
                 
-                /* Check if this block group is good candidate for allocation */
-                if ((free_inodes >= avg_free_inodes) && (free_blocks > 0)) {
+                /*
+                 * Check if this block group is a good candidate
+                 * for allocation.
+                 *
+                 * The criterion is based on the average number
+                 * of free inodes, unless we examine the last block
+                 * group. In that case the last block group might
+                 * have less than the average number of free inodes,
+                 * but it still needs to be taken as a candidate
+                 * because the previous block groups have zero free
+                 * blocks.
+                 */
+                if (((free_inodes >= avg_free_inodes) || (bgid == bg_count - 1)) &&
+                    (free_blocks > 0)) {
                         /* Load block with bitmap */
                         uint32_t bitmap_block_addr = ext4_block_group_get_inode_bitmap(