From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cn.fujitsu.com ([222.73.24.84]:16007 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751466AbcA2FQd (ORCPT ); Fri, 29 Jan 2016 00:16:33 -0500 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Cc: dsterba@suse.cz, David Sterba Subject: [PATCH v3 01/22] btrfs-progs: convert: Introduce functions to read used space Date: Fri, 29 Jan 2016 13:03:11 +0800 Message-Id: <1454043812-7893-2-git-send-email-quwenruo@cn.fujitsu.com> In-Reply-To: <1454043812-7893-1-git-send-email-quwenruo@cn.fujitsu.com> References: <1454043812-7893-1-git-send-email-quwenruo@cn.fujitsu.com> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org List-ID: Before we do real convert, we need to read and build up used space cache tree for later data/meta separate chunk layout. This patch will iterate all used blocks in ext2 filesystem and record it into cctx->used cache tree, for later use. This provides the very basic of later btrfs-convert rework. Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- btrfs-convert.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 80 insertions(+) diff --git a/btrfs-convert.c b/btrfs-convert.c index 4baa68e..65841bd 100644 --- a/btrfs-convert.c +++ b/btrfs-convert.c @@ -81,6 +81,7 @@ struct btrfs_convert_context; struct btrfs_convert_operations { const char *name; int (*open_fs)(struct btrfs_convert_context *cctx, const char *devname); + int (*read_used_space)(struct btrfs_convert_context *cctx); int (*alloc_block)(struct btrfs_convert_context *cctx, u64 goal, u64 *block_ret); int (*alloc_block_range)(struct btrfs_convert_context *cctx, u64 goal, @@ -230,6 +231,73 @@ fail: return -1; } +static int __ext2_add_one_block(ext2_filsys fs, char *bitmap, + unsigned long group_nr, struct cache_tree *used) +{ + unsigned long offset; + unsigned i; + int ret = 0; + + offset = fs->super->s_first_data_block; + offset /= EXT2FS_CLUSTER_RATIO(fs); + offset += group_nr * fs->super->s_clusters_per_group; + for (i = 0; i < fs->super->s_clusters_per_group; i++) { + if (ext2fs_test_bit(i, bitmap)) { + u64 start; + + start = (i + offset) * EXT2FS_CLUSTER_RATIO(fs); + start *= fs->blocksize; + ret = add_merge_cache_extent(used, start, + fs->blocksize); + if (ret < 0) + break; + } + } + return ret; +} + +/* + * Read all used ext2 space into cctx->used cache tree + */ +static int ext2_read_used_space(struct btrfs_convert_context *cctx) +{ + ext2_filsys fs = (ext2_filsys)cctx->fs_data; + blk64_t blk_itr = EXT2FS_B2C(fs, fs->super->s_first_data_block); + struct cache_tree *used_tree = &cctx->used; + char *block_bitmap = NULL; + unsigned long i; + int block_nbytes; + int ret = 0; + + block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8; + /* Shouldn't happen */ + BUG_ON(!fs->block_map); + + block_bitmap = malloc(block_nbytes); + if (!block_bitmap) + return -ENOMEM; + + for (i = 0; i < fs->group_desc_count; i++) { + ret = ext2fs_get_block_bitmap_range2(fs->block_map, blk_itr, + block_nbytes * 8, block_bitmap); + if (ret) { + error("fail to get bitmap from ext2, %s", + strerror(-ret)); + break; + } + ret = __ext2_add_one_block(fs, block_bitmap, i, used_tree); + if (ret < 0) { + error("fail to build used space tree, %s", + strerror(-ret)); + break; + } + blk_itr += fs->super->s_clusters_per_group; + } + + free(block_bitmap); + return ret; +} + static void ext2_close_fs(struct btrfs_convert_context *cctx) { if (cctx->volume_name) { @@ -2418,6 +2486,7 @@ err: static const struct btrfs_convert_operations ext2_convert_ops = { .name = "ext2", .open_fs = ext2_open_fs, + .read_used_space = ext2_read_used_space, .alloc_block = ext2_alloc_block, .alloc_block_range = ext2_alloc_block_range, .copy_inodes = ext2_copy_inodes, @@ -2451,6 +2520,14 @@ static int convert_open_fs(const char *devname, return -1; } +/* + * Read used space + */ +static int convert_read_used_space(struct btrfs_convert_context *cctx) +{ + return cctx->convert_ops->read_used_space(cctx); +} + static int do_convert(const char *devname, int datacsum, int packing, int noxattr, u32 nodesize, int copylabel, const char *fslabel, int progress, u64 features) @@ -2474,6 +2551,9 @@ static int do_convert(const char *devname, int datacsum, int packing, int noxatt ret = convert_open_fs(devname, &cctx); if (ret) goto fail; + ret = convert_read_used_space(&cctx); + if (ret) + goto fail; blocksize = cctx.blocksize; total_bytes = (u64)blocksize * (u64)cctx.block_count; -- 2.7.0