btrfs-progs: fi usage: support mixed blockgroups

Properly account the duplicated block groups and global reserve.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=110111
Reported-by: Chris Murphy <bugzilla@colorremedies.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/cmds-fi-usage.c b/cmds-fi-usage.c
index 0299fcc..33bf403 100644 (file)
--- a/cmds-fi-usage.c
+++ b/cmds-fi-usage.c
@@ -337,6 +337,7 @@ static int print_filesystem_usage_overall(int fd, struct chunk_info *chunkinfo,
        u64 free_estimated = 0;
        u64 free_min = 0;
        int max_data_ratio = 1;
+       int mixed = 0;
 
        sargs = load_space_info(fd, path);
        if (!sargs) {
@@ -394,10 +395,9 @@ static int print_filesystem_usage_overall(int fd, struct chunk_info *chunkinfo,
                        l_global_reserve_used = sargs->spaces[i].used_bytes;
                }
                if ((flags & (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA))
-                       == (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA)) {
-                       warning("MIXED blockgroups not handled");
+                   == (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA)) {
+                       mixed = 1;
                }
-
                if (flags & BTRFS_BLOCK_GROUP_DATA) {
                        r_data_used += sargs->spaces[i].used_bytes * ratio;
                        r_data_chunks += sargs->spaces[i].total_bytes * ratio;
@@ -414,13 +414,20 @@ static int print_filesystem_usage_overall(int fd, struct chunk_info *chunkinfo,
                }
        }
 
-       r_total_chunks = r_data_chunks + r_metadata_chunks + r_system_chunks;
-       r_total_used = r_data_used + r_metadata_used + r_system_used;
+       r_total_chunks = r_data_chunks + r_system_chunks;
+       r_total_used = r_data_used + r_system_used;
+       if (!mixed) {
+               r_total_chunks += r_metadata_chunks;
+               r_total_used += r_metadata_used;
+       }
        r_total_unused = r_total_size - r_total_chunks;
 
        /* Raw / Logical = raid factor, >= 1 */
        data_ratio = (double)r_data_chunks / l_data_chunks;
-       metadata_ratio = (double)r_metadata_chunks / l_metadata_chunks;
+       if (mixed)
+               metadata_ratio = data_ratio;
+       else
+               metadata_ratio = (double)r_metadata_chunks / l_metadata_chunks;
 
 #if 0
        /* add the raid5/6 allocated space */
@@ -437,6 +444,13 @@ static int print_filesystem_usage_overall(int fd, struct chunk_info *chunkinfo,
         * In non-mixed case there's no difference.
         */
        free_estimated = (r_data_chunks - r_data_used) / data_ratio;
+       /*
+        * For mixed-bg the metadata are left out in calculations thus global
+        * reserve would be lost. Part of it could be permanently allocated,
+        * we have to subtract the used bytes so we don't go under zero free.
+        */
+       if (mixed)
+               free_estimated -= l_global_reserve - l_global_reserve_used;
        free_min = free_estimated;
 
        /* Chop unallocatable space */