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authorKevin2014-11-15 11:48:36 +0800
committerKevin2014-11-15 11:48:36 +0800
commitd04075478d378d9e15f3e1abfd14b0bd124077d4 (patch)
tree733dd964582f388b9e3e367c249946cd32a2851f /fs/ext4/format/alloc.c
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init commit via android 4.4 uboot
Diffstat (limited to 'fs/ext4/format/alloc.c')
-rwxr-xr-xfs/ext4/format/alloc.c274
1 files changed, 274 insertions, 0 deletions
diff --git a/fs/ext4/format/alloc.c b/fs/ext4/format/alloc.c
new file mode 100755
index 0000000..8cfd57d
--- /dev/null
+++ b/fs/ext4/format/alloc.c
@@ -0,0 +1,274 @@
+/*
+ * alloc.c --- allocate new inodes, blocks for ext2fs
+ *
+ * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#include <common.h>
+//#include <ext_common.h>
+//#include <ext4fs.h>
+#include <malloc.h>
+#include <stddef.h>
+#include <linux/stat.h>
+#include <linux/time.h>
+
+
+#include "ext2_fs.h"
+#include "ext2fs.h"
+
+/*
+ * Check for uninit block bitmaps and deal with them appropriately
+ */
+static void check_block_uninit(ext2_filsys fs, ext2fs_block_bitmap map,
+ dgrp_t group)
+{
+ blk_t i;
+ blk_t blk, super_blk, old_desc_blk, new_desc_blk;
+ int old_desc_blocks;
+
+ if (!(EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) ||
+ !(fs->group_desc[group].bg_flags & EXT2_BG_BLOCK_UNINIT))
+ return;
+
+ blk = (group * fs->super->s_blocks_per_group) +
+ fs->super->s_first_data_block;
+
+ ext2fs_super_and_bgd_loc(fs, group, &super_blk,
+ &old_desc_blk, &new_desc_blk, 0);
+
+ if (fs->super->s_feature_incompat &
+ EXT2_FEATURE_INCOMPAT_META_BG)
+ old_desc_blocks = fs->super->s_first_meta_bg;
+ else
+ old_desc_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
+
+ for (i=0; i < fs->super->s_blocks_per_group; i++, blk++) {
+ if ((blk == super_blk) ||
+ (old_desc_blk && old_desc_blocks &&
+ (blk >= old_desc_blk) &&
+ (blk < old_desc_blk + old_desc_blocks)) ||
+ (new_desc_blk && (blk == new_desc_blk)) ||
+ (blk == fs->group_desc[group].bg_block_bitmap) ||
+ (blk == fs->group_desc[group].bg_inode_bitmap) ||
+ (blk >= fs->group_desc[group].bg_inode_table &&
+ (blk < fs->group_desc[group].bg_inode_table
+ + fs->inode_blocks_per_group)))
+ ext2fs_fast_mark_block_bitmap(map, blk);
+ else
+ ext2fs_fast_unmark_block_bitmap(map, blk);
+ }
+ fs->group_desc[group].bg_flags &= ~EXT2_BG_BLOCK_UNINIT;
+ ext2fs_group_desc_csum_set(fs, group);
+}
+
+/*
+ * Check for uninit inode bitmaps and deal with them appropriately
+ */
+static void check_inode_uninit(ext2_filsys fs, ext2fs_inode_bitmap map,
+ dgrp_t group)
+{
+ ext2_ino_t i, ino;
+
+ if (!(EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) ||
+ !(fs->group_desc[group].bg_flags & EXT2_BG_INODE_UNINIT))
+ return;
+
+ ino = (group * fs->super->s_inodes_per_group) + 1;
+ for (i=0; i < fs->super->s_inodes_per_group; i++, ino++)
+ ext2fs_fast_unmark_inode_bitmap(map, ino);
+
+ fs->group_desc[group].bg_flags &= ~EXT2_BG_INODE_UNINIT;
+ check_block_uninit(fs, fs->block_map, group);
+}
+
+/*
+ * Right now, just search forward from the parent directory's block
+ * group to find the next free inode.
+ *
+ * Should have a special policy for directories.
+ */
+errcode_t ext2fs_new_inode(ext2_filsys fs, ext2_ino_t dir,
+ int mode EXT2FS_ATTR((unused)),
+ ext2fs_inode_bitmap map, ext2_ino_t *ret)
+{
+ ext2_ino_t dir_group = 0;
+ ext2_ino_t i;
+ ext2_ino_t start_inode;
+
+ EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+ if (!map)
+ map = fs->inode_map;
+ if (!map)
+ return EXT2_ET_NO_INODE_BITMAP;
+
+ if (dir > 0)
+ dir_group = (dir - 1) / EXT2_INODES_PER_GROUP(fs->super);
+
+ start_inode = (dir_group * EXT2_INODES_PER_GROUP(fs->super)) + 1;
+ if (start_inode < EXT2_FIRST_INODE(fs->super))
+ start_inode = EXT2_FIRST_INODE(fs->super);
+ if (start_inode > fs->super->s_inodes_count)
+ return EXT2_ET_INODE_ALLOC_FAIL;
+ i = start_inode;
+
+ do {
+ if (((i - 1) % EXT2_INODES_PER_GROUP(fs->super)) == 0)
+ check_inode_uninit(fs, map, (i - 1) /
+ EXT2_INODES_PER_GROUP(fs->super));
+
+ if (!ext2fs_fast_test_inode_bitmap(map, i))
+ break;
+ i++;
+ if (i > fs->super->s_inodes_count)
+ i = EXT2_FIRST_INODE(fs->super);
+ } while (i != start_inode);
+
+ if (ext2fs_test_inode_bitmap(map, i))
+ return EXT2_ET_INODE_ALLOC_FAIL;
+ *ret = i;
+ return 0;
+}
+
+/*
+ * Stupid algorithm --- we now just search forward starting from the
+ * goal. Should put in a smarter one someday....
+ */
+errcode_t ext2fs_new_block(ext2_filsys fs, blk_t goal,
+ ext2fs_block_bitmap map, blk_t *ret)
+{
+ blk_t i;
+
+ EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+ if (!map)
+ map = fs->block_map;
+ if (!map)
+ return EXT2_ET_NO_BLOCK_BITMAP;
+ if (!goal || (goal >= fs->super->s_blocks_count))
+ goal = fs->super->s_first_data_block;
+ i = goal;
+ check_block_uninit(fs, map,
+ (i - fs->super->s_first_data_block) /
+ EXT2_BLOCKS_PER_GROUP(fs->super));
+ do {
+ if (((i - fs->super->s_first_data_block) %
+ EXT2_BLOCKS_PER_GROUP(fs->super)) == 0)
+ check_block_uninit(fs, map,
+ (i - fs->super->s_first_data_block) /
+ EXT2_BLOCKS_PER_GROUP(fs->super));
+
+ if (!ext2fs_fast_test_block_bitmap(map, i)) {
+ *ret = i;
+ return 0;
+ }
+ i++;
+ if (i >= fs->super->s_blocks_count)
+ i = fs->super->s_first_data_block;
+ } while (i != goal);
+ return EXT2_ET_BLOCK_ALLOC_FAIL;
+}
+
+/*
+ * This function zeros out the allocated block, and updates all of the
+ * appropriate filesystem records.
+ */
+errcode_t ext2fs_alloc_block(ext2_filsys fs, blk_t goal,
+ char *block_buf, blk_t *ret)
+{
+ errcode_t retval;
+ blk_t block;
+ char *buf = 0;
+
+ if (!block_buf) {
+ retval = ext2fs_get_mem(fs->blocksize, &buf);
+ if (retval)
+ return retval;
+ block_buf = buf;
+ }
+ memset(block_buf, 0, fs->blocksize);
+
+ if (fs->get_alloc_block) {
+ blk64_t new;
+
+ retval = (fs->get_alloc_block)(fs, (blk64_t) goal, &new);
+ if (retval)
+ goto fail;
+ block = (blk_t) new;
+ } else {
+ if (!fs->block_map) {
+ retval = ext2fs_read_block_bitmap(fs);
+ if (retval)
+ goto fail;
+ }
+
+ retval = ext2fs_new_block(fs, goal, 0, &block);
+ if (retval)
+ goto fail;
+ }
+
+ retval = io_channel_write_blk(fs->io, block, 1, block_buf);
+ if (retval)
+ goto fail;
+
+ ext2fs_block_alloc_stats(fs, block, +1);
+ *ret = block;
+
+fail:
+ if (buf)
+ ext2fs_free_mem(&buf);
+ return retval;
+}
+
+errcode_t ext2fs_get_free_blocks(ext2_filsys fs, blk_t start, blk_t finish,
+ int num, ext2fs_block_bitmap map, blk_t *ret)
+{
+ blk_t b = start;
+
+ EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+ if (!map)
+ map = fs->block_map;
+ if (!map)
+ return EXT2_ET_NO_BLOCK_BITMAP;
+ if (!b)
+ b = fs->super->s_first_data_block;
+ if (!finish)
+ finish = start;
+ if (!num)
+ num = 1;
+ do {
+ if (b+num-1 > fs->super->s_blocks_count)
+ b = fs->super->s_first_data_block;
+ if (ext2fs_fast_test_block_bitmap_range(map, b, num)) {
+ *ret = b;
+ return 0;
+ }
+ b++;
+ } while (b != finish);
+ return EXT2_ET_BLOCK_ALLOC_FAIL;
+}
+
+void ext2fs_set_alloc_block_callback(ext2_filsys fs,
+ errcode_t (*func)(ext2_filsys fs,
+ blk64_t goal,
+ blk64_t *ret),
+ errcode_t (**old)(ext2_filsys fs,
+ blk64_t goal,
+ blk64_t *ret))
+{
+ if (!fs || fs->magic != EXT2_ET_MAGIC_EXT2FS_FILSYS)
+ return;
+
+ if (old)
+ *old = fs->get_alloc_block;
+
+ fs->get_alloc_block = func;
+}