An extent_io_tree is used for all free space information. This allows
removal of ext2_alloc_block and ext2_free_block, and makes
create_ext2_image less ext2-specific.
---
convert.c | 154 +++++++++++++++++++++++++++++++++++++++----------------------
1 files changed, 99 insertions(+), 55 deletions(-)
diff --git a/convert.c b/convert.c
index d037c98..c48f8ba 100644
--- a/convert.c
+++ b/convert.c
@@ -95,29 +95,10 @@ static int close_ext2fs(ext2_filsys fs)
return 0;
}
-static int ext2_alloc_block(ext2_filsys fs, u64 goal, u64 *block_ret)
+static int ext2_cache_free_extents(ext2_filsys ext2_fs,
+ struct extent_io_tree *free_tree)
{
- blk_t block;
-
- if (!ext2fs_new_block(fs, goal, NULL, &block)) {
- ext2fs_fast_mark_block_bitmap(fs->block_map, block);
- *block_ret = block;
- return 0;
- }
- return -ENOSPC;
-}
-
-static int ext2_free_block(ext2_filsys fs, u64 block)
-{
- BUG_ON(block != (blk_t)block);
- ext2fs_fast_unmark_block_bitmap(fs->block_map, block);
- return 0;
-}
-
-static int cache_free_extents(struct btrfs_root *root, ext2_filsys ext2_fs)
-
-{
- int i, ret = 0;
+ int ret = 0;
blk_t block;
u64 bytenr;
u64 blocksize = ext2_fs->blocksize;
@@ -127,29 +108,68 @@ static int cache_free_extents(struct btrfs_root *root,
ext2_filsys ext2_fs)
if (ext2fs_fast_test_block_bitmap(ext2_fs->block_map, block))
continue;
bytenr = block * blocksize;
- ret = set_extent_dirty(&root->fs_info->free_space_cache,
- bytenr, bytenr + blocksize - 1, 0);
+ ret = set_extent_dirty(free_tree, bytenr,
+ bytenr + blocksize - 1, 0);
BUG_ON(ret);
}
+ return 0;
+}
+
+/* mark btrfs-reserved blocks as used */
+static void adjust_free_extents(ext2_filsys ext2_fs,
+ struct extent_io_tree *free_tree)
+{
+ int i;
+ u64 bytenr;
+ u64 blocksize = ext2_fs->blocksize;
+
+ clear_extent_dirty(free_tree, 0, BTRFS_SUPER_INFO_OFFSET - 1, 0);
+
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
bytenr = btrfs_sb_offset(i);
bytenr &= ~((u64)STRIPE_LEN - 1);
if (bytenr >= blocksize * ext2_fs->super->s_blocks_count)
break;
- clear_extent_dirty(&root->fs_info->free_space_cache, bytenr,
- bytenr + STRIPE_LEN - 1, 0);
+ clear_extent_dirty(free_tree, bytenr, bytenr + STRIPE_LEN - 1,
+ 0);
}
+}
- clear_extent_dirty(&root->fs_info->free_space_cache,
- 0, BTRFS_SUPER_INFO_OFFSET - 1, 0);
-
+static int alloc_blocks(struct extent_io_tree *free_tree,
+ u64 *blocks, int num, u64 blocksize)
+{
+ u64 start;
+ u64 end;
+ u64 last = 0;
+ u64 mask = blocksize - 1;
+ int ret;
+ while(num) {
+ ret = find_first_extent_bit(free_tree, last, &start, &end,
+ EXTENT_DIRTY);
+ if (ret)
+ goto fail;
+ last = end + 1;
+ if (start & mask)
+ start = (start & mask) + blocksize;
+ if (last - start < blocksize)
+ continue;
+ *blocks++ = start;
+ num--;
+ last = start + blocksize;
+ clear_extent_dirty(free_tree, start, last - 1, 0);
+ }
return 0;
+fail:
+ fprintf(stderr, "not enough free space\n");
+ return -ENOSPC;
}
static int custom_alloc_extent(struct btrfs_root *root, u64 num_bytes,
u64 hint_byte, struct btrfs_key *ins)
{
+ u64 blocksize = root->sectorsize;
+ u64 mask = blocksize - 1;
u64 start;
u64 end;
u64 last = hint_byte;
@@ -171,6 +191,8 @@ static int custom_alloc_extent(struct btrfs_root *root, u64
num_bytes,
start = max(last, start);
last = end + 1;
+ if (start & mask)
+ start = (start & mask) + blocksize;
if (last - start < num_bytes)
continue;
@@ -1186,9 +1208,9 @@ static int create_image_file_range(struct
btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
struct btrfs_inode_item *inode,
u64 start_byte, u64 end_byte,
- ext2_filsys ext2_fs)
+ struct extent_io_tree *orig_free_tree)
{
- u32 blocksize = ext2_fs->blocksize;
+ u32 blocksize = root->sectorsize;
u32 block = start_byte / blocksize;
u32 last_block = (end_byte + blocksize - 1) / blocksize;
int ret = 0;
@@ -1205,7 +1227,8 @@ static int create_image_file_range(struct
btrfs_trans_handle *trans,
.errcode = 0,
};
for (; start_byte < end_byte; block++, start_byte += blocksize) {
- if (!ext2fs_fast_test_block_bitmap(ext2_fs->block_map, block))
+ if (test_range_bit(orig_free_tree, start_byte,
+ start_byte + blocksize, EXTENT_DIRTY, 1))
continue;
ret = block_iterate_proc(NULL, block, block, &data);
if (ret & BLOCK_ABORT) {
@@ -1234,8 +1257,8 @@ fail:
/*
* Create the ext2fs image file.
*/
-static int create_ext2_image(struct btrfs_root *root, ext2_filsys ext2_fs,
- const char *name)
+static int create_ext2_image(struct btrfs_root *root, const char *name,
+ struct extent_io_tree *orig_free_tree)
{
int ret;
struct btrfs_key key;
@@ -1348,7 +1371,7 @@ next:
if (bytenr > last_byte) {
ret = create_image_file_range(trans, root, objectid,
&btrfs_inode, last_byte,
- bytenr, ext2_fs);
+ bytenr, orig_free_tree);
if (ret)
goto fail;
}
@@ -1370,7 +1393,7 @@ next:
if (total_bytes > last_byte) {
ret = create_image_file_range(trans, root, objectid,
&btrfs_inode, last_byte,
- total_bytes, ext2_fs);
+ total_bytes, orig_free_tree);
if (ret)
goto fail;
}
@@ -2332,9 +2355,23 @@ err:
return ret;
}
+static int copy_dirtiness(struct extent_io_tree *out,
+ struct extent_io_tree *in)
+{
+ int ret;
+ u64 start, end, last = 0;
+ while (!find_first_extent_bit(in, last, &start, &end, EXTENT_DIRTY)) {
+ ret = set_extent_dirty(out, start, end, 0);
+ if (ret)
+ return ret;
+ last = end + 1;
+ }
+ return 0;
+}
+
int do_convert(const char *devname, int datacsum, int packing, int noxattr)
{
- int i, fd, ret;
+ int fd, ret;
u32 blocksize;
u64 blocks[7];
u64 total_bytes;
@@ -2342,7 +2379,11 @@ int do_convert(const char *devname, int datacsum, int
packing, int noxattr)
ext2_filsys ext2_fs;
struct btrfs_root *root;
struct btrfs_root *ext2_root;
+ struct extent_io_tree free_tree;
+ struct extent_io_tree orig_free_tree;
+ extent_io_tree_init(&free_tree);
+ extent_io_tree_init(&orig_free_tree);
ret = open_ext2fs(devname, &ext2_fs);
if (ret) {
fprintf(stderr, "unable to open the Ext2fs\n");
@@ -2359,13 +2400,23 @@ int do_convert(const char *devname, int datacsum, int
packing, int noxattr)
fprintf(stderr, "filetype feature is missing\n");
goto fail;
}
- for (i = 0; i < 7; i++) {
- ret = ext2_alloc_block(ext2_fs, 0, blocks + i);
- if (ret) {
- fprintf(stderr, "not enough free space\n");
- goto fail;
- }
- blocks[i] *= blocksize;
+ ret = ext2_cache_free_extents(ext2_fs, &orig_free_tree);
+ if (ret) {
+ fprintf(stderr, "error during cache_free_extents %d\n", ret);
+ goto fail;
+ }
+ /* preserve first 64KiB, just in case */
+ clear_extent_dirty(&orig_free_tree, 0, BTRFS_SUPER_INFO_OFFSET - 1, 0);
+
+ ret = copy_dirtiness(&free_tree, &orig_free_tree);
+ if (ret) {
+ fprintf(stderr, "error during copy_dirtiness %d\n", ret);
+ goto fail;
+ }
+ adjust_free_extents(ext2_fs, &free_tree);
+ ret = alloc_blocks(&free_tree, blocks, 7, blocksize);
+ if (ret) {
+ goto fail;
}
super_bytenr = blocks[0];
fd = open(devname, O_RDWR);
@@ -2391,17 +2442,9 @@ int do_convert(const char *devname, int datacsum, int
packing, int noxattr)
fprintf(stderr, "unable to open ctree\n");
goto fail;
}
- ret = cache_free_extents(root, ext2_fs);
- if (ret) {
- fprintf(stderr, "error during cache_free_extents %d\n", ret);
- goto fail;
- }
+ copy_dirtiness(&root->fs_info->free_space_cache, &free_tree);
+ extent_io_tree_cleanup(&free_tree);
root->fs_info->extent_ops = &extent_ops;
- /* recover block allocation bitmap */
- for (i = 0; i < 7; i++) {
- blocks[i] /= blocksize;
- ext2_free_block(ext2_fs, blocks[i]);
- }
ret = init_btrfs(root);
if (ret) {
fprintf(stderr, "unable to setup the root tree\n");
@@ -2419,11 +2462,12 @@ int do_convert(const char *devname, int datacsum, int
packing, int noxattr)
fprintf(stderr, "unable to create subvol\n");
goto fail;
}
- ret = create_ext2_image(ext2_root, ext2_fs, "image");
+ ret = create_ext2_image(ext2_root, "image", &orig_free_tree);
if (ret) {
fprintf(stderr, "error during create_ext2_image %d\n", ret);
goto fail;
}
+ extent_io_tree_cleanup(&orig_free_tree);
printf("cleaning up system chunk.\n");
ret = cleanup_sys_chunk(root, ext2_root);
if (ret) {
--
1.6.4.4
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