-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 05/19/2010 06:00 PM, Edward Shishkin wrote: > Leonardo Chiquitto wrote: >> On Wed, May 19, 2010 at 4:22 PM, Jeff Mahoney <jeffm@xxxxxxxx> wrote: >> >>> In its early life, reiserfs had an evolving s_max_bytes. It started out >>> at 4 GB, then was raised to MAX_LFS_FILESIZE, then dropped to 2 TiB >>> when >>> it was observed that struct stat only had a 32-bit st_blocks field. >>> >>> Since then, both the kernel and glibc have evolved as well and now both >>> support 64-bit st_blocks. Applications that can't deal with these >>> ranges >>> are assumed to be "legacy" or "broken." File systems now routinely >>> support file sizes much larger than can be represented by 2^32 * 512. >>> >>> But we never revisited that limitation. ReiserFS has always been >>> able to >>> support larger file sizes (up to 16 TiB, in fact), but the s_max_bytes >>> limitation has prevented that. >>> >>> This patch adds a max_file_offset helper to set s_max_bytes to a more >>> appropriate value. I noticed that XFS adjusts the limit based on the >>> CPU but I'd prefer to err on the side of compatibility and place the >>> limit at the smaller of the 32-bit MAX_LFS_FILESIZE and the maximum >>> supported by the file system. At a 4k block size, this is conveniently >>> also the advertised maximum file size of reiserfs. >>> >>> Update: This version properly extends PAGE_SIZE_CACHE so the math works >>> on 32-bit systems. >>> >>> This bug is tracked at: >>> https://bugzilla.novell.com/show_bug.cgi?id=592100 >>> >>> Signed-off-by: Jeff Mahoney <jeffm@xxxxxxxx> >>> - --- >>> fs/reiserfs/super.c | 17 +++++++++++++---- >>> 1 file changed, 13 insertions(+), 4 deletions(-) >>> >>> - --- a/fs/reiserfs/super.c >>> +++ b/fs/reiserfs/super.c >>> @@ -1309,6 +1309,18 @@ out_err: >>> return err; >>> } >>> +static inline loff_t >>> +reiserfs_max_file_offset(struct super_block *sb) >>> +{ >>> + /* Limited by stat_data->sd_blocks, 2^32-1 blocks */ >>> + loff_t fs_max = ((u64)sb->s_blocksize << 32) - sb->s_blocksize; >>> + >>> + /* Limited by 32-bit MAX_LFS_FILESIZE */ >>> + loff_t page_cache_max = (((u64)PAGE_CACHE_SIZE << 31)-1); >>> + >>> + return min(fs_max, page_cache_max); >>> +} >>> + >>> static int read_super_block(struct super_block *s, int offset) >>> { >>> struct buffer_head *bh; >>> @@ -1398,10 +1410,7 @@ static int read_super_block(struct super >>> s->dq_op = &reiserfs_quota_operations; >>> #endif >>> - /* new format is limited by the 32 bit wide i_blocks field, >>> want to >>> - - ** be one full block below that. >>> - - */ >>> - - s->s_maxbytes = (512LL << 32) - s->s_blocksize; >>> + s->s_maxbytes = reiserfs_max_file_offset(s); >>> return 0; >>> } >>> >> >> Hello ReiserFS developers, >> >> Any chance to have this patch submitted to 2.6.35? > > I wouldn't rely on this. Reiserfsprogs also should be aware > of the new limits. It's all long.. I certainly hope not. Things would be broken already. The 2 TB limit is 2048 * 2^32. - -Jeff >> We're hitting the 2TB >> file limit here and this patch resolves the problem. >> >> Thanks, >> Leonardo >> -- >> To unsubscribe from this list: send the line "unsubscribe >> reiserfs-devel" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >> > - -- Jeff Mahoney SUSE Labs -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.15 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org/ iEYEARECAAYFAkv1iTwACgkQLPWxlyuTD7I/yQCcCrGCVlu15YW7tBPbXb08SR7U xc0AmwT5nDgG9T9apDXyQtqlpkx5vwva =gb6N -----END PGP SIGNATURE----- -- To unsubscribe from this list: send the line "unsubscribe reiserfs-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
