Changeset b12ca16 in mainline

Timestamp:

2011-11-18T15:30:24Z (12 years ago)

Author:

Frantisek Princ <frantisek.princ@…>

Branches:

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

Children:

d5ba17f

Parents:

e18de3c

Message:

improved block allocator - but has some bugs

Location:

uspace

Files:

• lib/ext4/libext4_balloc.c (modified) (10 diffs)
• lib/ext4/libext4_balloc.h (modified) (1 diff)
• lib/ext4/libext4_bitmap.c (modified) (2 diffs)
• lib/ext4/libext4_filesystem.c (modified) (6 diffs)
• lib/ext4/libext4_superblock.c (modified) (1 diff)
• lib/ext4/libext4_superblock.h (modified) (1 diff)
• srv/fs/ext4fs/ext4fs_ops.c (modified) (2 diffs)

uspace/lib/ext4/libext4_balloc.c

@@ -31 +31 @@
  */ 
 
+/**
+ * @file        libext4_balloc.c
+ * @brief       Block allocator.
+ */
+
 #include <errno.h>
 #include <sys/types.h>
 #include "libext4.h"
 
-int ext4_bitmap_free_block(ext4_filesystem_t *fs, ext4_inode_ref_t *inode_ref, uint32_t block_index)
-{
-        int rc;
-        uint32_t blocks_per_group;
-        uint32_t block_group;
-        uint32_t index_in_group;
-        uint32_t bitmap_block;
-        uint32_t block_size;
-        ext4_block_group_ref_t *bg_ref;
-        block_t *block;
-        uint32_t first_block;
-
-        block_size = ext4_superblock_get_block_size(fs->superblock);
-        blocks_per_group = ext4_superblock_get_blocks_per_group(fs->superblock);
-        first_block = ext4_superblock_get_first_data_block(fs->superblock);
+static uint32_t ext4_balloc_blockaddr2_index_in_group(ext4_superblock_t *sb,
+                uint32_t block_addr)
+{
+        uint32_t blocks_per_group = ext4_superblock_get_blocks_per_group(sb);
+        uint32_t first_block = ext4_superblock_get_first_data_block(sb);
 
         // First block == 0 or 1
         if (first_block == 0) {
-                block_group = block_index / blocks_per_group;
-                index_in_group = block_index % blocks_per_group;
+                return block_addr % blocks_per_group;
         } else {
-                block_group = (block_index - 1) / blocks_per_group;
-                index_in_group = (block_index - 1) % blocks_per_group;
-        }
-
+                return (block_addr - 1) % blocks_per_group;
+        }
+}
+
+static uint32_t ext4_balloc_index_in_group2blockaddr(ext4_superblock_t *sb,
+                uint32_t index, uint32_t bgid)
+{
+        uint32_t blocks_per_group = ext4_superblock_get_blocks_per_group(sb);
+
+        if (ext4_superblock_get_first_data_block(sb) == 0) {
+                return bgid * blocks_per_group + index;
+        } else {
+                return bgid * blocks_per_group + index + 1;
+        }
+
+}
+
+static uint32_t ext4_balloc_get_bgid_of_block(ext4_superblock_t *sb,
+                uint32_t block_addr)
+{
+        uint32_t blocks_per_group = ext4_superblock_get_blocks_per_group(sb);
+        uint32_t first_block = ext4_superblock_get_first_data_block(sb);
+
+        // First block == 0 or 1
+        if (first_block == 0) {
+                return block_addr / blocks_per_group;
+        } else {
+                return (block_addr - 1) / blocks_per_group;
+        }
+}
+
+
+int ext4_balloc_free_block(ext4_filesystem_t *fs, ext4_inode_ref_t *inode_ref, uint32_t block_addr)
+{
+        int rc;
+
+        uint32_t block_group = ext4_balloc_get_bgid_of_block(fs->superblock, block_addr);
+        uint32_t index_in_group = ext4_balloc_blockaddr2_index_in_group(fs->superblock, block_addr);
+
+        ext4_block_group_ref_t *bg_ref;
         rc = ext4_filesystem_get_block_group_ref(fs, block_group, &bg_ref);
         if (rc != EOK) {
-                return rc;
-        }
-
-        bitmap_block = ext4_block_group_get_block_bitmap(bg_ref->block_group);
-
-        rc = block_get(&block, fs->device, bitmap_block, 0);
-        if (rc != EOK) {
-                return rc;
-        }
-
-        ext4_bitmap_free_bit(block->data, index_in_group);
-
-        block->dirty = true;
-        rc = block_put(block);
-        if (rc != EOK) {
-                return rc;
-        }
+                EXT4FS_DBG("error in loading bg_ref \%d", rc);
+                return rc;
+        }
+
+        uint32_t bitmap_block_addr = ext4_block_group_get_block_bitmap(bg_ref->block_group);
+        block_t *bitmap_block;
+        rc = block_get(&bitmap_block, fs->device, bitmap_block_addr, 0);
+        if (rc != EOK) {
+                EXT4FS_DBG("error in loading bitmap \%d", rc);
+                return rc;
+        }
+
+        ext4_bitmap_free_bit(bitmap_block->data, index_in_group);
+        bitmap_block->dirty = true;
+
+        rc = block_put(bitmap_block);
+        if (rc != EOK) {
+                // Error in saving bitmap
+                ext4_filesystem_put_block_group_ref(bg_ref);
+                EXT4FS_DBG("error in saving bitmap \%d", rc);
+                return rc;
+        }
+
+        uint32_t block_size = ext4_superblock_get_block_size(fs->superblock);
 
         uint64_t ino_blocks = ext4_inode_get_blocks_count(fs->superblock, inode_ref->inode);
@@ -99 +136 @@
         }
 
+//      EXT4FS_DBG("released block \%u (idx = \%u)", block_addr, index_in_group);
         return EOK;
 }
 
-
-static uint32_t ext4_bitmap_find_goal(ext4_filesystem_t *fs, ext4_inode_ref_t *inode_ref)
-{
+static uint32_t ext4_balloc_get_first_data_block_in_group(
+                ext4_superblock_t *sb, ext4_block_group_t *bg, uint32_t bgid)
+{
+        uint32_t block_group_count = ext4_superblock_get_block_group_count(sb);
+        uint32_t inode_table_first_block = ext4_block_group_get_inode_table_first_block(bg);
+        uint16_t inode_table_item_size = ext4_superblock_get_inode_size(sb);
+        uint32_t inodes_per_group = ext4_superblock_get_inodes_per_group(sb);
+        uint32_t block_size = ext4_superblock_get_block_size(sb);
+        uint32_t inode_table_bytes;
+
+        if (bgid < block_group_count - 1) {
+                inode_table_bytes = inodes_per_group * inode_table_item_size;
+        } else {
+                // last block group could be smaller
+                uint32_t inodes_count_total = ext4_superblock_get_inodes_count(sb);
+                inode_table_bytes =
+                                (inodes_count_total - ((block_group_count - 1) * inodes_per_group))
+                                * inode_table_item_size;
+        }
+
+        uint32_t inode_table_blocks = inode_table_bytes / block_size;
+
+        if (inode_table_bytes % block_size) {
+                inode_table_blocks++;
+        }
+
+        return inode_table_first_block + inode_table_blocks;
+}
+
+
+static uint32_t ext4_balloc_find_goal(ext4_filesystem_t *fs, ext4_inode_ref_t *inode_ref)
+{
+        int rc;
         uint32_t goal = 0;
 
-        int rc;
         uint64_t inode_size = ext4_inode_get_size(fs->superblock, inode_ref->inode);
         uint32_t block_size = ext4_superblock_get_block_size(fs->superblock);
         uint32_t inode_block_count = inode_size / block_size;
 
-
         if (inode_size % block_size != 0) {
                 inode_block_count++;
@@ -119 +185 @@
         if (inode_block_count > 0) {
                 // TODO check retval
-//              EXT4FS_DBG("has blocks");
                 ext4_filesystem_get_inode_data_block_index(fs, inode_ref->inode, inode_block_count - 1, &goal);
 
                 // TODO
                 // If goal == 0 -> SPARSE file !!!
+
                 goal++;
+
+//              EXT4FS_DBG("goal = \%u, inode_block_count == \%u", goal, inode_block_count);
+
                 return goal;
         }
 
-//      uint32_t blocks_per_group = ext4_superblock_get_blocks_per_group(fs->superblock);
+//      EXT4FS_DBG("Inode has no blocks");
 
         // Identify block group of inode
@@ -141 +210 @@
         }
 
+        uint32_t block_group_count = ext4_superblock_get_block_group_count(fs->superblock);
         uint32_t inode_table_first_block = ext4_block_group_get_inode_table_first_block(bg_ref->block_group);
         uint16_t inode_table_item_size = ext4_superblock_get_inode_size(fs->superblock);
-        uint32_t inode_table_bytes = inodes_per_group * inode_table_item_size;
+        uint32_t inode_table_bytes;
+
+        if (block_group < block_group_count - 1) {
+                inode_table_bytes = inodes_per_group * inode_table_item_size;
+        } else {
+                // last block group could be smaller
+                uint32_t inodes_count_total = ext4_superblock_get_inodes_count(fs->superblock);
+                inode_table_bytes =
+                                (inodes_count_total - ((block_group_count - 1) * inodes_per_group))
+                                * inode_table_item_size;
+        }
+
         uint32_t inode_table_blocks = inode_table_bytes / block_size;
 
@@ -157 +238 @@
 }
 
-int ext4_bitmap_alloc_block(ext4_filesystem_t *fs, ext4_inode_ref_t *inode_ref, uint32_t *fblock)
+int ext4_balloc_alloc_block(ext4_filesystem_t *fs, ext4_inode_ref_t *inode_ref, uint32_t *fblock)
 {
         int rc;
-        ext4_block_group_ref_t *bg_ref;
+        uint32_t allocated_block = 0;
+
         uint32_t bitmap_block;
         block_t *block;
         uint32_t rel_block_idx = 0;
-        uint32_t index_in_group;
-        uint32_t tmp;
-
-        uint32_t allocated_block = 0;
-
-        // Determine GOAL
-        uint32_t goal = ext4_bitmap_find_goal(fs, inode_ref);
-
-        uint32_t block_size = ext4_superblock_get_block_size(fs->superblock);
-
-        //if (goal == 0) - unable to determine goal
+
+        // Find GOAL
+        uint32_t goal = ext4_balloc_find_goal(fs, inode_ref);
         if (goal == 0) {
                 // TODO
                 EXT4FS_DBG("ERRORR (goal == 0)");
-        }
-
-//      EXT4FS_DBG("goal = \%u", goal);
-
-        uint32_t blocks_per_group = ext4_superblock_get_blocks_per_group(fs->superblock);
-        uint32_t first_block = ext4_superblock_get_first_data_block(fs->superblock);
-
-        uint32_t block_group;
-
-        // First block == 0 or 1
-        if (first_block == 0) {
-                block_group = goal / blocks_per_group;
-                index_in_group = goal % blocks_per_group;
-        } else {
-                block_group = (goal - 1) / blocks_per_group;
-                index_in_group = (goal - 1) % blocks_per_group;
-        }
-
-
+                return ENOSPC;
+        }
+
+        // Load block group number for goal and relative index
+        uint32_t block_group = ext4_balloc_get_bgid_of_block(fs->superblock, goal);
+        uint32_t index_in_group = ext4_balloc_blockaddr2_index_in_group(fs->superblock, goal);
 //      EXT4FS_DBG("block_group = \%u, index_in_group = \%u", block_group, index_in_group);
 
+
+
+        ext4_block_group_ref_t *bg_ref;
         rc = ext4_filesystem_get_block_group_ref(fs, block_group, &bg_ref);
         if (rc != EOK) {
-                return rc;
+                EXT4FS_DBG("initial BG ref not loaded");
+                return rc;
+        }
+
+        uint32_t first_in_group =
+                        ext4_balloc_get_first_data_block_in_group(fs->superblock,
+                                        bg_ref->block_group, block_group);
+
+        if (index_in_group < first_in_group) {
+                index_in_group = first_in_group;
         }
 
@@ -210 +283 @@
         if (rc != EOK) {
                 ext4_filesystem_put_block_group_ref(bg_ref);
+                EXT4FS_DBG("initial bitmap not loaded");
                 return rc;
         }
@@ -215 +289 @@
 //      EXT4FS_DBG("bitmap loaded");
 
+        // Check if goal is free
         if (ext4_bitmap_is_free_bit(block->data, index_in_group)) {
-
-//              EXT4FS_DBG("goal is free");
-
                 ext4_bitmap_set_bit(block->data, index_in_group);
                 block->dirty = true;
@@ -224 +296 @@
                 if (rc != EOK) {
                         // TODO error
-                        EXT4FS_DBG("error in saving bitmap \%d", rc);
+                        EXT4FS_DBG("goal check: error in saving initial bitmap \%d", rc);
+                        ext4_filesystem_put_block_group_ref(bg_ref);
+                        return rc;
                 }
 
                 allocated_block = goal;
-                goto end;
-
-        }
-
-//      EXT4FS_DBG("try 63 blocks after goal");
+                goto success;
+
+        }
+
+        uint32_t blocks_in_group = ext4_superblock_get_blocks_in_group(fs->superblock, block_group);
+
+//      EXT4FS_DBG("index = \%u (goal = \%u), blocks_in_group = \%u", index_in_group, goal, blocks_in_group);
+
+        uint32_t end_idx = (index_in_group + 63) & ~63;
+        if (end_idx > blocks_in_group) {
+                end_idx = blocks_in_group;
+        }
+
         // Try to find free block near to goal
-        for (tmp = index_in_group + 1; (tmp < blocks_per_group) && (tmp < ((index_in_group + 63) & ~63)); ++tmp) {
-
-//              EXT4FS_DBG("trying \%u", tmp);
-
-                if (ext4_bitmap_is_free_bit(block->data, tmp)) {
-
-//                      EXT4FS_DBG("block \%u is free -> allocate it", tmp);
-
-                        ext4_bitmap_set_bit(block->data, tmp);
+        for (uint32_t tmp_idx = index_in_group + 1; tmp_idx < end_idx; ++tmp_idx) {
+                if (ext4_bitmap_is_free_bit(block->data, tmp_idx)) {
+
+                        ext4_bitmap_set_bit(block->data, tmp_idx);
+                        block->dirty = true;
+                        rc = block_put(block);
+                        if (rc != EOK) {
+                                // TODO error
+                                EXT4FS_DBG("near blocks: error in saving initial bitmap \%d", rc);
+                        }
+
+                        allocated_block = ext4_balloc_index_in_group2blockaddr(
+                                        fs->superblock, tmp_idx, block_group);
+
+
+//                      EXT4FS_DBG("block \%u (idx = \%u) allocated, goal = \%u", allocated_block, tmp_idx, goal);
+
+                        goto success;
+                }
+
+        }
+
+        // Find free BYTE in bitmap
+//      EXT4FS_DBG("try find free byte in own BG");
+        rc = ext4_bitmap_find_free_byte_and_set_bit(block->data, index_in_group, &rel_block_idx, blocks_in_group);
+        if (rc == EOK) {
+                block->dirty = true;
+                rc = block_put(block);
+                if (rc != EOK) {
+                        // TODO error
+                        EXT4FS_DBG("free byte: error in saving initial bitmap \%d", rc);
+                }
+
+                allocated_block = ext4_balloc_index_in_group2blockaddr(
+                                fs->superblock, rel_block_idx, block_group);
+
+//              EXT4FS_DBG("block \%u allocated, index = \%u, goal = \%u", allocated_block, rel_block_idx, goal);
+
+                goto success;
+        }
+
+        // Find free bit in bitmap
+        EXT4FS_DBG("find free bit");
+        rc = ext4_bitmap_find_free_bit_and_set(block->data, index_in_group, &rel_block_idx, blocks_in_group);
+        if (rc == EOK) {
+                block->dirty = true;
+                rc = block_put(block);
+                if (rc != EOK) {
+                        // TODO error
+                        EXT4FS_DBG("free bit: error in saving initial bitmap \%d", rc);
+                }
+
+                allocated_block = ext4_balloc_index_in_group2blockaddr(
+                                fs->superblock, rel_block_idx, block_group);
+
+                EXT4FS_DBG("find free bit: block \%u allocated, index = \%u, goal = \%u", allocated_block, rel_block_idx, goal);
+
+                goto success;
+        }
+
+        block_put(block);
+        ext4_filesystem_put_block_group_ref(bg_ref);
+
+        // Try other block groups
+        uint32_t block_group_count = ext4_superblock_get_block_group_count(fs->superblock);
+
+        uint32_t bgid = (block_group + 1) % block_group_count;
+        uint32_t count = block_group_count;
+
+        while (count > 0) {
+                EXT4FS_DBG("trying group \%u", bgid);
+
+                rc = ext4_filesystem_get_block_group_ref(fs, bgid, &bg_ref);
+                if (rc != EOK) {
+                        EXT4FS_DBG("errrrrrrrrrrr");
+                        return rc;
+                }
+
+                // Load bitmap
+                bitmap_block = ext4_block_group_get_block_bitmap(bg_ref->block_group);
+
+                rc = block_get(&block, fs->device, bitmap_block, 0);
+                if (rc != EOK) {
+                        ext4_filesystem_put_block_group_ref(bg_ref);
+                        EXT4FS_DBG("errrrrrrrrrr");
+                        return rc;
+                }
+
+                first_in_group = ext4_balloc_get_first_data_block_in_group(
+                                fs->superblock, bg_ref->block_group, bgid);
+                index_in_group = ext4_balloc_blockaddr2_index_in_group(fs->superblock,
+                                                first_in_group);
+                blocks_in_group = ext4_superblock_get_blocks_in_group(fs->superblock, bgid);
+
+                if (index_in_group < first_in_group) {
+                        index_in_group = first_in_group;
+                }
+
+//              EXT4FS_DBG("trying free byte in bg \%u", bgid);
+                rc = ext4_bitmap_find_free_byte_and_set_bit(block->data, index_in_group, &rel_block_idx, blocks_in_group);
+                if (rc == EOK) {
                         block->dirty = true;
                         rc = block_put(block);
@@ -250 +424 @@
                         }
 
-                        if (first_block == 0) {
-                                allocated_block = blocks_per_group * block_group + tmp;
-                        } else {
-                                allocated_block = blocks_per_group * block_group + tmp + 1;
+                        allocated_block = ext4_balloc_index_in_group2blockaddr(
+                                        fs->superblock, rel_block_idx, bgid);
+
+                        EXT4FS_DBG("byte: block \%u allocated, index = \%u, goal = \%u", allocated_block, rel_block_idx, goal);
+
+                        goto success;
+                }
+
+                // Find free bit in bitmap
+                rc = ext4_bitmap_find_free_bit_and_set(block->data, index_in_group, &rel_block_idx, blocks_in_group);
+//              EXT4FS_DBG("trying free bit in bg \%u", bgid);
+                if (rc == EOK) {
+                        block->dirty = true;
+                        rc = block_put(block);
+                        if (rc != EOK) {
+                                // TODO error
+                                EXT4FS_DBG("error in saving bitmap \%d", rc);
                         }
 
-                        goto end;
-                }
-        }
-
-//      EXT4FS_DBG("try find free byte");
-
-        // Find free BYTE in bitmap
-        rc = ext4_bitmap_find_free_byte_and_set_bit(block->data, index_in_group, &rel_block_idx, block_size);
-        if (rc == EOK) {
-                block->dirty = true;
-                rc = block_put(block);
-                if (rc != EOK) {
-                        // TODO error
-                        EXT4FS_DBG("error in saving bitmap \%d", rc);
-                }
-
-                if (first_block == 0) {
-                        allocated_block = blocks_per_group * block_group + rel_block_idx;
-                } else {
-                        allocated_block = blocks_per_group * block_group + rel_block_idx + 1;
-                }
-
-                goto end;
-        }
-
-//      EXT4FS_DBG("try find free bit");
-
-        // Find free bit in bitmap
-        rc = ext4_bitmap_find_free_bit_and_set(block->data, index_in_group, &rel_block_idx, block_size);
-        if (rc == EOK) {
-                block->dirty = true;
-                rc = block_put(block);
-                if (rc != EOK) {
-                        // TODO error
-                        EXT4FS_DBG("error in saving bitmap \%d", rc);
-                }
-
-                if (first_block == 0) {
-                        allocated_block = blocks_per_group * block_group + rel_block_idx;
-                } else {
-                        allocated_block = blocks_per_group * block_group + rel_block_idx + 1;
-                }
-
-                goto end;
-        }
-
-
-        // TODO Try other block groups
-        EXT4FS_DBG("try other block group");
+                        allocated_block = ext4_balloc_index_in_group2blockaddr(
+                                        fs->superblock, rel_block_idx, bgid);
+
+                        EXT4FS_DBG("bit: block \%u allocated, index = \%u, goal = \%u", allocated_block, rel_block_idx, goal);
+
+                        goto success;
+                }
+
+
+                // Next group
+                block_put(block);
+                ext4_filesystem_put_block_group_ref(bg_ref);
+                bgid = (bgid + 1) % block_group_count;
+                count--;
+        }
+
+        EXT4FS_DBG("No free block found");
         return ENOSPC;
 
-end:
+success:
 
         ;
 //      EXT4FS_DBG("returning block \%u", allocated_block);
+
+        uint32_t block_size = ext4_superblock_get_block_size(fs->superblock);
 
         // TODO decrement superblock free blocks count
@@ -329 +486 @@
         ext4_filesystem_put_block_group_ref(bg_ref);
 
-//      EXT4FS_DBG("block \%u allocated", blocks_per_group * block_group + rel_block_idx + 1);
-
-
+//      if (goal > 1980)
+//              EXT4FS_DBG("block \%u allocated", allocated_block);
 
         *fblock = allocated_block;
         return EOK;
 }
-
-
-/**
- * @file        libext4_balloc.c
- * @brief       TODO
- */
-
 
 

uspace/lib/ext4/libext4_balloc.h

@@ -37 +37 @@
 #include "libext4_filesystem.h"
 
-extern int ext4_bitmap_free_block(ext4_filesystem_t *,
+extern int ext4_balloc_free_block(ext4_filesystem_t *,
                 ext4_inode_ref_t *, uint32_t);
-extern int ext4_bitmap_alloc_block(ext4_filesystem_t *,
+extern int ext4_balloc_alloc_block(ext4_filesystem_t *,
                 ext4_inode_ref_t *, uint32_t *);
 

uspace/lib/ext4/libext4_bitmap.c

@@ -76 +76 @@
 }
 
-int ext4_bitmap_find_free_byte_and_set_bit(uint8_t *bitmap, uint32_t start, uint32_t *index, uint32_t size)
+int ext4_bitmap_find_free_byte_and_set_bit(uint8_t *bitmap, uint32_t start, uint32_t *index, uint32_t max)
 {
-        uint8_t *pos = bitmap + (start / 8) + 1;
+        uint32_t idx;
+        if (start % 8) {
+                idx = start + (8 - (start % 8));
+        } else {
+                idx = start;
+        }
 
-        while (pos < bitmap + size) {
+        uint8_t *pos = bitmap + (idx / 8);
+
+        while (idx < max) {
+
                 if (*pos == 0) {
                         *pos |= 1;
 
-                        *index = (pos - bitmap) * 8;
+                        *index = idx;
                         return EOK;
                 }
 
+                idx += 8;
                 ++pos;
         }
 
         return ENOSPC;
-
 }
 
-int ext4_bitmap_find_free_bit_and_set(uint8_t *bitmap, uint32_t start, uint32_t *index, uint32_t size)
+int ext4_bitmap_find_free_bit_and_set(uint8_t *bitmap, uint32_t start_idx,
+                uint32_t *index, uint32_t max)
 {
-        uint8_t *pos = bitmap + (start / 8);
-        int i;
-        uint8_t value, new_value;
+        uint8_t *pos = bitmap + (start_idx / 8);
+        uint32_t idx = start_idx;
+        bool byte_part = false;
 
-        while (pos < bitmap + size) {
+        // Check the rest of byte
+        while ((idx % 8) != 0) {
+                byte_part = true;
+
+                if (*pos & (1 << (idx % 8))) {
+                        *pos |= (1 << (idx % 8));
+                        *index = idx;
+                        return EOK;
+                }
+
+                ++idx;
+        }
+
+        if (byte_part) {
+                ++pos;
+        }
+
+        while (idx < max) {
+
                 if ((*pos & 255) != 255) {
                         // free bit found
@@ -107 +134 @@
                 }
 
+                idx += 8;
                 ++pos;
         }
 
-        // Check the byte containing start
-        if (pos == bitmap + (start / 8)) {
-                for (i = start % 8; i < 8; ++i) {
-                        value = *pos;
-                        if ((value & (1 << i)) == 0) {
+
+        if (idx < max) {
+                for (uint8_t i = 0; i < 8; ++i) {
+                        if ((*pos & (1 << i)) == 0) {
                                 // free bit found
-                                new_value = value | (1 << i);
-                                *pos = new_value;
-                                *index = (pos - bitmap) * 8 + i;
+                                *pos |=  (1 << i);
+                                *index = idx;
                                 return EOK;
                         }
-                }
-        }
-
-        if (pos < bitmap + size) {
-
-                for(i = 0; i < 8; ++i) {
-                        value = *pos;
-
-                        if ((value & (1 << i)) == 0) {
-                                // free bit found
-                                new_value = value | (1 << i);
-                                *pos = new_value;
-                                *index = (pos - bitmap) * 8 + i;
-                                return EOK;
-                        }
+                        idx++;
                 }
         }

uspace/lib/ext4/libext4_filesystem.c

@@ -72 +72 @@
 
         /* Initialize block caching */
-        // TODO set cache MODE to write through (now writeback for faster testing)
-        rc = block_cache_init(service_id, block_size, 0, CACHE_MODE_WB);
+        rc = block_cache_init(service_id, block_size, 0, CACHE_MODE_WT);
         if (rc != EOK) {
                 block_fini(fs->device);
@@ -387 +386 @@
                 // TODO
                 return ENOTSUP;
-
         }
 
@@ -418 +416 @@
 
         if (current_block == 0) {
-                rc = ext4_bitmap_alloc_block(fs, inode_ref, &new_block_addr);
+                rc = ext4_balloc_alloc_block(fs, inode_ref, &new_block_addr);
                 if (rc != EOK) {
                         // TODO error
@@ -460 +458 @@
                 current_block = uint32_t_le2host(((uint32_t*)block->data)[offset_in_block]);
 
-                if (current_block == 0) {
-                        if (level > 1) {
-
-                                rc = ext4_bitmap_alloc_block(fs, inode_ref, &new_block_addr);
-                                if (rc != EOK) {
-                                        // TODO error
-                                        EXT4FS_DBG("allocation error");
-                                }
-
-                                rc = block_get(&new_block, fs->device, new_block_addr, BLOCK_FLAGS_NOREAD);
-                                if (rc != EOK) {
-                                        // TODO error
-
-                                        EXT4FS_DBG("BBB: error block loading");
-
-                                }
-                                memset(new_block->data, 0, block_size);
-                                new_block->dirty = true;
-
-                                block_put(new_block);
-
-                                ((uint32_t*)block->data)[offset_in_block] = host2uint32_t_le(new_block_addr);
-                                block->dirty = true;
-                                current_block = new_block_addr;
-                        } else {
-                                ((uint32_t*)block->data)[offset_in_block] = host2uint32_t_le(fblock);
-                                block->dirty = true;
+                if ((level > 1) && (current_block == 0)) {
+                        rc = ext4_balloc_alloc_block(fs, inode_ref, &new_block_addr);
+                        if (rc != EOK) {
+                                // TODO error
+                                EXT4FS_DBG("allocation error");
                         }
+                        EXT4FS_DBG("BBB: new addr \%u, offset = \%u, level = \%u", new_block_addr, offset_in_block, level);
+
+                        rc = block_get(&new_block, fs->device, new_block_addr, BLOCK_FLAGS_NOREAD);
+                        if (rc != EOK) {
+                                // TODO error
+
+                                EXT4FS_DBG("BBB: error block loading");
+
+                        }
+                        memset(new_block->data, 0, block_size);
+                        new_block->dirty = true;
+
+                        rc = block_put(new_block);
+                        if (rc != EOK) {
+                                EXT4FS_DBG("BBB: error indirect block saving");
+                        }
+
+                        ((uint32_t*)block->data)[offset_in_block] = host2uint32_t_le(new_block_addr);
+                        block->dirty = true;
+                        current_block = new_block_addr;
+                }
+
+                if (level == 1) {
+                        ((uint32_t*)block->data)[offset_in_block] = host2uint32_t_le(fblock);
+                        block->dirty = true;
                 }
 
@@ -537 +538 @@
 
                 ext4_inode_set_direct_block(inode, iblock, 0);
-                return ext4_bitmap_free_block(fs, inode_ref, fblock);
+                return ext4_balloc_free_block(fs, inode_ref, fblock);
         }
 
@@ -601 +602 @@
         }
 
-        return ext4_bitmap_free_block(fs, inode_ref, fblock);
-
-}
-
+        return ext4_balloc_free_block(fs, inode_ref, fblock);
+
+}
 
 /**

uspace/lib/ext4/libext4_superblock.c

@@ -280 +280 @@
 }
 
+uint32_t ext4_superblock_get_block_group_count(ext4_superblock_t *sb)
+{
+        uint64_t blocks_count = ext4_superblock_get_blocks_count(sb);
+        uint32_t blocks_per_group = ext4_superblock_get_blocks_per_group(sb);
+
+        uint32_t block_groups_count = blocks_count / blocks_per_group;
+
+        if (blocks_count % blocks_per_group) {
+                block_groups_count++;
+        }
+
+        return block_groups_count;
+
+}
+
+uint32_t ext4_superblock_get_blocks_in_group(ext4_superblock_t *sb, uint32_t bgid)
+{
+        uint32_t block_group_count = ext4_superblock_get_block_group_count(sb);
+        uint32_t blocks_per_group = ext4_superblock_get_blocks_per_group(sb);
+        uint64_t total_blocks = ext4_superblock_get_blocks_count(sb);
+
+        if (bgid < block_group_count - 1) {
+                return blocks_per_group;
+        } else {
+                return (total_blocks - ((block_group_count - 1) * blocks_per_group));
+        }
+
+}
+
+uint32_t ext4_superblock_get_inodes_in_group(ext4_superblock_t *sb, uint32_t bgid)
+{
+        uint32_t block_group_count = ext4_superblock_get_block_group_count(sb);
+        uint32_t inodes_per_group = ext4_superblock_get_inodes_per_group(sb);
+        uint32_t total_inodes = ext4_superblock_get_inodes_count(sb);
+
+        if (bgid < block_group_count - 1) {
+                return inodes_per_group;
+        } else {
+                return (total_inodes - ((block_group_count - 1) * inodes_per_group));
+        }
+
+}
+
 /**
  * @}

uspace/lib/ext4/libext4_superblock.h

@@ -302 +302 @@
 extern int ext4_superblock_check_sanity(ext4_superblock_t *);
 
+extern uint32_t ext4_superblock_get_block_group_count(ext4_superblock_t *);
+extern uint32_t ext4_superblock_get_blocks_in_group(ext4_superblock_t *, uint32_t);
+extern uint32_t ext4_superblock_get_inodes_in_group(ext4_superblock_t *, uint32_t);
+
 #endif
 

uspace/srv/fs/ext4fs/ext4fs_ops.c

@@ -973 +973 @@
         if (fblock == 0) {
 
-                rc =  ext4_bitmap_alloc_block(fs, inode_ref, &fblock);
+                rc =  ext4_balloc_alloc_block(fs, inode_ref, &fblock);
                 if (rc != EOK) {
                         EXT4FS_DBG("allocation failed");
@@ -981 +981 @@
                 }
 
-                ext4_filesystem_set_inode_data_block_index(fs, inode_ref, iblock, fblock);
+                rc = ext4_filesystem_set_inode_data_block_index(fs, inode_ref, iblock, fblock);
+                if (rc != EOK) {
+                        EXT4FS_DBG("ERROR: setting index failed");
+                }
                 inode_ref->dirty = true;
 
                 flags = BLOCK_FLAGS_NOREAD;
-
         }