2010/6/22 <tytso@xxxxxxx> > > On Mon, Jun 21, 2010 at 09:44:31PM +0800, Hsuan-Ting wrote: > > Hi Ted, > > > > Resize seems not work when the size is bigger than 16TB (offline resize). > > > > My test machine: > > x64 platform 2.6.32 kernel + this newest patch > > > > 1. <16TB ext4 enlarge to >16TB (offline) > > a. I use "8 x 2TB WD disks" and "mdadm" build linear raid > > b. then use mkfs.ext4 to make ext4 file system > > c. grow the linear raid to "10 X 2TB" > > d. finally it grow to "2.X TB" smaller than before > > This doesn't surprise me. We should add some checks to simply not > allow the file system growing greater than 16TB if the 64-bit feature > is not set for now. Making this work is going to be tricky, because > enabling the 64-bit feature doubles the size of the block group > descriptors, which means we have to make room for them. This could > involve moving files out of the way, as well as moving the inode > table. > > This means that we may want to enable the 64-bit feature flag if there > is an expectation that the filesystem might be grown to a size large > enough where this would be an issue. Sounds like I must enable 64-bit feature when mkfs. Then it will work, right? But base on my test, it will occur core dump when resize: (gdb) bt #0 0x00000000004160bf in ext2fs_test_bit64 () #1 0x0000000000416318 in ba_test_bmap () #2 0x0000000000410629 in ext2fs_test_generic_bmap () #3 0x0000000000410656 in ext2fs_test_block_bitmap_range2 () #4 0x000000000040873d in ext2fs_get_free_blocks2 () #5 0x000000000040936d in ext2fs_allocate_group_table () #6 0x0000000000404456 in adjust_fs_info () #7 0x0000000000404a81 in resize_fs () #8 0x00000000004069c7 in main () I do the following modification (to enable "EXT4_FEATURE_INCOMPAT_64BIT" and "EXT2_FLAG_64BITS"): misc/mke2fs.c : @@ -1530,6 +1945,8 @@ static void PRS(int argc, char *argv[]) EXT2_BLOCK_SIZE(&fs_param)); exit(1); } + fs_param.s_feature_incompat |= EXT4_FEATURE_INCOMPAT_64BIT; ext2fs_blocks_count_set(&fs_param, fs_blocks_count); resize/resize2fs.c : @@ -585,6 +598,9 @@ static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size) if (retval) return retval; + fs->super->s_feature_incompat |= EXT4_FEATURE_INCOMPAT_64BIT; retval = adjust_fs_info(fs, rfs->old_fs, rfs->reserve_blocks, new_size); lib/ext2fs/openfs.c : @@ -109,6 +109,8 @@ errcode_t ext2fs_open2(const char *name, const char *io_options, memset(fs, 0, sizeof(struct struct_ext2_filsys)); fs->magic = EXT2_ET_MAGIC_EXT2FS_FILSYS; fs->flags = flags; + fs->flags |= EXT2_FLAG_64BITS; Did I mistake something? > > > 2. >16TB offline resize, the steps is similiar as before. > > a. I use "9 x 2TB WD disks" build linear raid > > b. mkfs.ext4 and not mount > > c. grow the linear raid to "10 X 2TB" > > d. do resize > > e. finally it grow to "2.X TB" smaller than before > > > > I try to on "EXT4_FEATURE_INCOMPAT_64BIT" and "EXT2_FLAG_64BITS" > > when mkfs and resize. > > And modify ext2fs_div_ceil code to ext2fs_div64_ceil. > > It seems work something, the fs size isn't grow but also not deduce, > > remain the same. > > I'm not sure I understand that last sentence; it's not parsing as an > understandable English sentence, sorry. Are you saying that both > attempts to grow and shrink the filesystem is failing? If so, how? > Are you getting an error message? Is it appearing to succeed but the > file system size isn't changing? Sorry for my poor English. The last sentence means "succeed but the file system size isn't changing". I also remove "flex_bg" feature in this case. Thanks. -HsuanTing > > Thanks for the bug report, > > - Ted > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html