On 5/3/24 17:37, Qu Wenruo wrote:
在 2024/5/3 18:38, Anand Jain 写道:This patch, along with the dependent patches below, adds support for ext4 unwritten file extents as preallocated file extent in btrfs.btrfs-progs: convert: refactor ext2_create_file_extents add argument ext2_inode btrfs-progs: convert: struct blk_iterate_data, add ext2-specific file inode pointers btrfs-progs: convert: refactor __btrfs_record_file_extent to add a prealloc flagThe patch is developed with POV of portability with the current e2fsprogs library. Testcase:$ dd if=/dev/urandom of=/mnt/test/foo bs=4K count=1 conv=fsync status=none $ dd if=/dev/urandom of=/mnt/test/foo bs=4K count=2 conv=fsync seek=1 status=none$ xfs_io -f -c 'falloc -k 12K 12K' /mnt/test/foo$ dd if=/dev/zero of=/mnt/test/foo bs=4K count=1 conv=fsync seek=6 status=none$ filefrag -v /mnt/test/foo Filesystem type is: ef53 File size of /mnt/test/foo is 28672 (7 blocks of 4096 bytes)ext: logical_offset: physical_offset: length: expected: flags:0: 0.. 0: 33280.. 33280: 1: 1: 1.. 2: 33792.. 33793: 2: 33281:2: 3.. 5: 33281.. 33283: 3: 33794: unwritten 3: 6.. 6: 33794.. 33794: 1: 33284: last,eof$ sha256sum /mnt/test/foo18619b678a5c207a971a0aa931604f48162e307c57ecdec450d5f095fe9f32c7 /mnt/test/fooConvert and compare the checksum Before: $ filefrag -v /mnt/test/foo Filesystem type is: 9123683e File size of /mnt/test/foo is 28672 (7 blocks of 4096 bytes)ext: logical_offset: physical_offset: length: expected: flags: 0: 0.. 0: 33280.. 33280: 1: shared 1: 1.. 2: 33792.. 33793: 2: 33281: shared 2: 3.. 6: 33281.. 33284: 4: 33794: last,shared,eof/mnt/test/foo: 3 extents found $ sha256sum /mnt/test/foo6874a1733e5785682210d69c07f256f684cf5433c7235ed29848b4a4d52030e0 /mnt/test/fooAfter: $ filefrag -v /mnt/test/foo Filesystem type is: 9123683e File size of /mnt/test/foo is 28672 (7 blocks of 4096 bytes)ext: logical_offset: physical_offset: length: expected: flags: 0: 0.. 0: 33280.. 33280: 1: shared 1: 1.. 2: 33792.. 33793: 2: 33281: shared 2: 3.. 5: 33281.. 33283: 3: 33794: unwritten,shared 3: 6.. 6: 33794.. 33794: 1: 33284: last,shared,eof/mnt/test/foo: 4 extents found $ sha256sum /mnt/test/foo18619b678a5c207a971a0aa931604f48162e307c57ecdec450d5f095fe9f32c7 /mnt/test/fooSigned-off-by: Anand Jain <anand.jain@xxxxxxxxxx> --- RFC: Limited tested. Is there a ready file or test case available to exercise the feature? convert/source-fs.c | 49 ++++++++++++++++++++++++++++++++++++++++++++- convert/source-fs.h | 1 + 2 files changed, 49 insertions(+), 1 deletion(-) diff --git a/convert/source-fs.c b/convert/source-fs.c index 9039b0e66758..647ea1f29060 100644 --- a/convert/source-fs.c +++ b/convert/source-fs.c @@ -239,6 +239,45 @@ fail: return ret; }+int find_prealloc(struct blk_iterate_data *data, int index, bool *prealloc)This function is called for every file extent we're going to create. I'm not a big fan of doing so many lookup.My question is, is this the only way to determine the flag of the data extent?My instinct says there should be a straight forward way to determine if a file extent is preallocated or not, just like what we do in our file extent items.
Thus during the ext2fs_block_iterate2(), there should be some way to tell if a block is preallocated or not.
Unfortunately, the callback doesn't provide the extent flags. Unless, I miss something?
Thx, Anand
Thus adding ext4 ML to get some feedback. Thanks, Qu+{ + ext2_extent_handle_t handle; + struct ext2fs_extent extent; + + if (ext2fs_extent_open2(data->ext2_fs, data->ext2_ino, + data->ext2_inode, &handle)) { + error("ext2fs_extent_open2 failed, inode %d", data->ext2_ino); + return -EINVAL; + } + + if (ext2fs_extent_goto2(handle, 0, index)) { + error("ext2fs_extent_goto2 failed, inode %d num_blocks %llu", + data->ext2_ino, data->num_blocks); + ext2fs_extent_free(handle); + return -EINVAL; + } + + memset(&extent, 0, sizeof(struct ext2fs_extent)); + if (ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent)) { + error("ext2fs_extent_get EXT2_EXTENT_CURRENT failed inode %d", + data->ext2_ino); + ext2fs_extent_free(handle); + return -EINVAL; + } + + if (extent.e_pblk != data->disk_block) {+ error("inode %d index %d found wrong extent e_pblk %llu wanted disk_block %llu",+ data->ext2_ino, index, extent.e_pblk, data->disk_block); + ext2fs_extent_free(handle); + return -EINVAL; + } + + if (extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT) + *prealloc = true; + + return 0; +} + /* * Record a file extent in original filesystem into btrfs one. * The special point is, old disk_block can point to a reserved range. @@ -257,6 +296,7 @@ int record_file_blocks(struct blk_iterate_data *data, u64 old_disk_bytenr = disk_block * sectorsize; u64 num_bytes = num_blocks * sectorsize; u64 cur_off = old_disk_bytenr; + int index = data->first_block; /* Hole, pass it to record_file_extent directly */ if (old_disk_bytenr == 0)@@ -276,6 +316,12 @@ int record_file_blocks(struct blk_iterate_data *data,u64 extent_num_bytes; u64 real_disk_bytenr; u64 cur_len; + bool prealloc = false; + + if (find_prealloc(data, index, &prealloc)) { + data->errcode = -1; + return -EINVAL; + } key.objectid = data->convert_ino; key.type = BTRFS_EXTENT_DATA_KEY;@@ -317,11 +363,12 @@ int record_file_blocks(struct blk_iterate_data *data,ret = btrfs_record_file_extent(data->trans, data->root, data->objectid, data->inode, file_pos, real_disk_bytenr, cur_len, - false); + prealloc); if (ret < 0) break; cur_off += cur_len; file_pos += cur_len; + index++; /* * No need to care about csum diff --git a/convert/source-fs.h b/convert/source-fs.h index 0e71e79eddcc..3922c444de10 100644 --- a/convert/source-fs.h +++ b/convert/source-fs.h@@ -156,5 +156,6 @@ int read_disk_extent(struct btrfs_root *root, u64 bytenr,u32 num_bytes, char *buffer); int record_file_blocks(struct blk_iterate_data *data, u64 file_block, u64 disk_block, u64 num_blocks);+int find_prealloc(struct blk_iterate_data *data, int index, bool *prealloc);#endif
