- added some btrfs qgroup functions

diff --git a/snapper/BtrfsUtils.cc b/snapper/BtrfsUtils.cc
index 22bc41103cb8cf22148341851f2e072f652511e9..121b72ae93c944f73759113720a3a4be17a4a6fd 100644 (file)
--- a/snapper/BtrfsUtils.cc
+++ b/snapper/BtrfsUtils.cc
@@ -422,6 +422,66 @@ namespace snapper
        }
 
 
+       vector<qgroup_t>
+       qgroup_query_children(int fd, qgroup_t qgroup)
+       {
+           struct btrfs_ioctl_search_args args;
+           memset(&args, 0, sizeof(args));
+
+           struct btrfs_ioctl_search_key* sk = &args.key;
+           sk->tree_id = BTRFS_QUOTA_TREE_OBJECTID;
+
+           sk->min_type = BTRFS_QGROUP_RELATION_KEY;
+           sk->max_type = BTRFS_QGROUP_RELATION_KEY;
+           sk->min_objectid = 0;
+           sk->max_objectid = BTRFS_LAST_FREE_OBJECTID;
+           sk->min_offset = 0;
+           sk->max_offset = (u64)(-1);
+           sk->min_transid = 0;
+           sk->max_transid = (u64)(-1);
+           sk->nr_items = 4096;
+
+           vector<qgroup_t> ret;
+
+           while (true)
+           {
+               if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0)
+                   throw runtime_error_with_errno("ioctl(BTRFS_IOC_TREE_SEARCH) failed", errno);
+
+               if (sk->nr_items == 0)
+                   break;
+
+               u64 off = 0;
+
+               for (unsigned int i = 0; i < sk->nr_items; ++i)
+               {
+                   struct btrfs_ioctl_search_header* sh = (struct btrfs_ioctl_search_header*)(args.buf + off);
+                   off += sizeof(*sh);
+
+                   if (sh->type != BTRFS_QGROUP_RELATION_KEY)
+                       throw std::runtime_error("sh->type != BTRFS_QGROUP_RELATION_KEY");
+
+                   if (sh->offset == qgroup)
+                       ret.push_back(sh->objectid);
+
+                   off += sh->len;
+
+                   sk->min_objectid = sh->objectid;
+                   sk->min_offset = sh->offset;
+               }
+
+               sk->nr_items = 4096;
+
+               if (sk->min_offset < (u64)(-1))
+                   sk->min_offset++;
+               else
+                   break;
+           }
+
+           return ret;
+       }
+
+
        QGroupUsage
        qgroup_query_usage(int fd, qgroup_t qgroup)
        {

diff --git a/snapper/BtrfsUtils.h b/snapper/BtrfsUtils.h
index 1e4421b542871d1fdbf6289e7dbc11ed6281edc6..179577e0e28b20b2cf7845ba7450544ca8db3354 100644 (file)
--- a/snapper/BtrfsUtils.h
+++ b/snapper/BtrfsUtils.h
@@ -26,11 +26,13 @@
 
 #include <stdint.h>
 #include <string>
+#include <vector>
 
 
 namespace snapper
 {
     using std::string;
+    using std::vector;
 
 
     namespace BtrfsUtils
@@ -73,6 +75,8 @@ namespace snapper
        void qgroup_assign(int fd, qgroup_t src, qgroup_t dst);
        void qgroup_remove(int fd, qgroup_t src, qgroup_t dst);
 
+       vector<qgroup_t> qgroup_query_children(int fd, qgroup_t qgroup);
+
        struct QGroupUsage
        {
            QGroupUsage() : referenced(0), referenced_compressed(0), exclusive(0),