| Message ID | e8659631b0481defe32fcde435432da630af6789.1704400902.git.kreijack@inwind.it (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | btrfs fi us: wrong values in case of raid5 and not root | expand |
On Thu, Jan 04, 2024 at 09:41:42PM +0100, Goffredo Baroncelli wrote: > From: Goffredo Baroncelli <kreijack@inwind.it> > > In case of a raid5/6 filesystem 'btrfs fi us' returns wrong values > without the root capabilities. > > $ sudo btrfs fi us /tmp/raid5fs # as root > Overall: > Device size: 3.00GiB > Device allocated: 1.51GiB <--- OK > Device unallocated: 1.49GiB <--- OK > Device missing: 0.00B > Device slack: 0.00B > Used: 769.03MiB <--- OK > Free (estimated): 1.32GiB (min: 1.32GiB) <-OK > Free (statfs, df): 1.32GiB > Data ratio: 1.50 <--- OK > Metadata ratio: 1.50 <--- OK > Global reserve: 5.50MiB (used: 0.00B) > Multiple profiles: no > [...] > > $ btrfs fi us /tmp/raid5fs # as user > WARNING: cannot read detailed chunk info, per-device usage will not be shown, run as root > Overall: > Device size: 3.00GiB > Device allocated: 0.00B <--- WRONG > Device unallocated: 3.00GiB <--- WRONG > Device missing: 0.00B > Device slack: 0.00B > Used: 0.00B <--- WRONG > Free (estimated): 0.00B (min: 8.00EiB) <- WRONG > Free (statfs, df): 1.32GiB > Data ratio: 0.00 <--- WRONG > Metadata ratio: 0.00 <--- WRONG > Global reserve: 5.50MiB (used: 0.00B) > Multiple profiles: no > [...] > > The reason is that the BTRFS_IOC_SPACE_INFO ioctl doesn't return enough > info. To bypass it a scan of the chunks is required when a raid5/6 > profile is present. > > To avoid providing wrong information, in case of a raid5/6 filesystem > without the root capabilities the "btrfs fi us" is not executed at all > and a warning with a suggestion to run it as root is printed. > > $ ./btrfs fi us /tmp/t/ > WARNING: cannot read detailed chunk info, per-device usage will not be shown, run as root > WARNING: due to the presence of a raid5/raid6 profile, we cannots compute some values; > WARNING: run as root instead. > $ > > Signed-off-by: Goffredo Baroncelli <kreijack@libero.it> Added to devel, thanks.
diff --git a/cmds/filesystem-usage.c b/cmds/filesystem-usage.c index 015c401e..9ba03d46 100644 --- a/cmds/filesystem-usage.c +++ b/cmds/filesystem-usage.c @@ -478,6 +478,8 @@ static int print_filesystem_usage_overall(int fd, const struct array *chunkinfos bool mixed = false; struct statvfs statvfs_buf; struct btrfs_ioctl_feature_flags feature_flags; + bool raid56 = false; + bool unreliable_allocated = false; sargs = load_space_info(fd, path); if (!sargs) { @@ -518,8 +520,10 @@ static int print_filesystem_usage_overall(int fd, const struct array *chunkinfos * computed separately. Setting ratio to 0 will not account * the chunks in this loop. */ - if (flags & BTRFS_BLOCK_GROUP_RAID56_MASK) + if (flags & BTRFS_BLOCK_GROUP_RAID56_MASK) { ratio = 0; + raid56 = true; + } if (ratio > max_data_ratio) max_data_ratio = ratio; @@ -610,6 +614,20 @@ static int print_filesystem_usage_overall(int fd, const struct array *chunkinfos ret = 0; } + /* + * if we don't have any chunk information (e.g. due to missing + * privileges) and is present a raid56 profile, the computation + * of 'unallocated', "data/metadata ratio", "free estimated" are + * wrong. + */ + unreliable_allocated = raid56 && chunkinfos->length == 0; + if (unreliable_allocated) { + warning("due to the presence of a raid5/raid6 profile, we cannots compute some values;"); + warning("run as root instead."); + ret = 1; + goto exit; + } + pr_verbose(LOG_DEFAULT, "Overall:\n"); pr_verbose(LOG_DEFAULT, " Device size:\t\t%*s\n", width,