remove statfs policy

README.md

@@ -10,20 +10,19 @@ Why create mergerfs when those exist? mhddfs isn't really maintained or flexible
 Policies
 ========
 
-Filesystem calls are broken up into 5 classes of policies: search, action, create, statfs, and none.
+Filesystem calls are broken up into 4 categories of policies: search, action, create, and none.
 
 Below shows each policy class, the FUSE calls they impact, and the policy names.
 
-####Policy classifications####
+#### Policy classifications ####
 | Class | FUSE calls | Policies |
 |-------|------------|----------|
 | search | access, getattr, getxattr, listxattr, open, readlink  | First Found (ff), First Found w/ Permission (ffwp), Newest (newest) |
 | action | chmod, link, removexattr, rmdir, setxattr, truncate, unlink, utimens | First Found (ff), First Found w/ Permission (ffwp), Newest (newest), All Found (all) |
 | create | create, mkdir, mknod | Existing Path (ep), Most Free Space (mfs), Existing Path Most Free Space (epmfs), Random (rand) |
-| statfs | statfs | Sum Used Max Free (sumf), Sum Used Sum Free (susf) |
-| none   | fallocate, fsync, ftruncate, ioctl, read, readdir, rename, symlink, write, release | |
+| none   | fallocate, fsync, ftruncate, ioctl, read, readdir, rename, statfs, symlink, write, release | |
 
-####Descriptions####
+#### Descriptions ####
 | Class/Policy | Description |
 |--------------|-------------|
 | search/ff | Given the order the paths were provided at mount time act on the first one found (regardless if stat would return EACCES). |
@@ -37,8 +36,10 @@ Below shows each policy class, the FUSE calls they impact, and the policy names.
 | create/mfs | Assuming the path is found to exist (ENOENT would not be returned) use the drive with the most free space available. |
 | create/epmfs | If the path exists in multiple locations use the one with the most free space. Otherwise fall back to mfs. |
 | create/rand | Pick a destination at random. Again the dirname of the full path must exist somewhere. |
-| statfs/sumf | When reporting the size of the filesystem it will show the sum of all used but the available space will be reported as the max available across the filesystems mounted. |
-| statfs/susf | As above but will report the sum of available space. Since the largest usable space is that of the filesystem with the most usable space this option is deceptive. |
+
+#### statvfs ####
+
+Since we aren't trying to stripe data across drives the free space of the mountpoint is just that of the source mount with the most free space at the moment.
 
 **NOTE:** create is really a search for existence and then create. The 'search' policy applies to the first part. If the [dirname](http://linux.die.net/man/3/dirname) of the full path is not found to exist [ENOENT](http://linux.die.net/man/3/errno) is returned.
 
@@ -46,7 +47,7 @@ Usage
 =====
 
 ```
-$ mergerfs -o create=epmfs,search=ff,action=ff,statfs=sumf <mountpoint> <dir0>:<dir1>:<dir2>
+$ mergerfs -o create=epmfs,search=ff,action=ff <mountpoint> <dir0>:<dir1>:<dir2>
 ```
 
 | Option | Values | Default |
@@ -54,7 +55,6 @@ $ mergerfs -o create=epmfs,search=ff,action=ff,statfs=sumf <mountpoint> <dir0>:<
 | search | ff, ffwp, newest | ff |
 | action | ff, ffwp, newest, all | ff |
 | create | ep, mfs, epmfs, rand | epmfs |
-| statfs | sumf, susf | sumf |
 
 Building
 ========
@@ -72,6 +72,7 @@ make WITHOUT_XATTR=1 - to build program without xattrs functionality
 Runtime Settings
 ================
 
+#### /.mergerfs pseudo file ####
 ```
 <mountpoint>/.mergerfs
 ```
@@ -85,7 +86,6 @@ Reading the file will result in a newline delimited list of current settings as
 action=ff
 create=epmfs
 search=ff
-statfs=sumf
 ```
 
 Writing to the file is buffered and waits till a newline to process. Meaning echo works well.
@@ -96,7 +96,25 @@ Writing to the file is buffered and waits till a newline to process. Meaning ech
 action=ff
 create=epmfs
 search=newest
-statfs=sumf
 ```
 
 *NOTE:* offset is not supported and ignored in both read and write. There is also a safety check which limits buffered + incoming length to a max of 1024 bytes.
+
+#### xattrs ####
+
+If xattrs has been enabled you can also use [{list,get,set}xattrs](http://linux.die.net/man/2/listxattr) on the pseudo file **.mergerfs** to modify the policies. The keys are **mergerfs.action**, **mergerfs.create**, and **mergerfs.search**.
+
+```
+[trapexit:/tmp/mount] $ attr -l .mergerfs
+Attribute "mergerfs.action" has a 3 byte value for .mergerfs
+Attribute "mergerfs.create" has a 6 byte value for .mergerfs
+Attribute "mergerfs.search" has a 3 byte value for .mergerfs
+
+[trapexit:/tmp/mount] $ attr -g mergerfs.action .mergerfs
+Attribute "mergerfs.action" had a 3 byte value for .mergerfs:
+ff
+
+[trapexit:/tmp/mount] 1 $ attr -s mergerfs.action -V ffwp .mergerfs
+Attribute "mergerfs.action" set to a 3 byte value for .mergerfs:
+ffwp
+```

src/config.cpp

@@ -63,8 +63,7 @@ namespace mergerfs
 
       ss << "action=" << policy.action.str() << std::endl
          << "create=" << policy.create.str() << std::endl
-         << "search=" << policy.search.str() << std::endl
-         << "statfs=" << policy.statfs.str() << std::endl;
+         << "search=" << policy.search.str() << std::endl;
 
       return ss.str();
     }

src/getxattr.cpp

@@ -56,8 +56,6 @@ _getxattr_controlfile(const Policy &policy,
     attrvalue = policy.create.str();
   else if(attrname == "user.mergerfs.search")
     attrvalue = policy.search.str();
-  else if(attrname == "user.mergerfs.statfs")
-    attrvalue = policy.statfs.str();
 
   if(attrvalue.empty())
     return -ENOATTR;

src/option_parser.cpp

@@ -68,9 +68,7 @@ process_opt(config::Config    &config,
   switch(argvalue.size())
     {
     case 2:
-      if(argvalue[0] == "statfs")
-        policy.statfs.fromString(argvalue[1]);
-      else if(argvalue[0] == "create")
+      if(argvalue[0] == "create")
         policy.create.fromString(argvalue[1]);
       else if(argvalue[0] == "search")
         policy.search.fromString(argvalue[1]);

src/policy.cpp

@@ -254,53 +254,4 @@ namespace mergerfs
         return NULL;
       }
   }
-
-  Policy::StatFS::StatFS(const Policy::StatFS::Type value)
-  {
-    *this = value;
-  }
-
-  Policy::StatFS&
-  Policy::StatFS::operator=(Policy::StatFS::Type value)
-  {
-    _str   = toString(value);
-    _value = fromString(_str);
-
-    return *this;
-  }
-
-  Policy::StatFS&
-  Policy::StatFS::operator=(const std::string str)
-  {
-    _value = fromString(str);
-    _str   = toString(_value);
-
-    return *this;
-  }
-
-  Policy::StatFS::Type
-  Policy::StatFS::fromString(const std::string str)
-  {
-    if(str == "susf")
-      return Policy::StatFS::SumUsedSumFree;
-    else if(str == "sumf")
-      return Policy::StatFS::SumUsedMaxFree;
-
-    return Policy::StatFS::Invalid;
-  }
-
-  std::string
-  Policy::StatFS::toString(const Policy::StatFS::Type value)
-  {
-    switch(value)
-      {
-      case Policy::StatFS::SumUsedSumFree:
-        return "susf";
-      case Policy::StatFS::SumUsedMaxFree:
-        return "sumf";
-      case Policy::StatFS::Invalid:
-      default:
-        return "invalid";
-      }
-  }
 }

src/policy.hpp

@@ -36,45 +36,12 @@ namespace mergerfs
   public:
     enum Type
       {
-        STATFS,
         ACTION,
         CREATE,
         SEARCH
       };
 
   public:
-    class StatFS
-    {
-    public:
-      enum Type
-        {
-          Invalid = -1,
-          SumUsedSumFree,
-          SumUsedMaxFree,
-          Max
-        };
-
-      StatFS(Type _value);
-
-    public:
-      operator Type() const { return _value; }
-      operator std::string() const { return _str; }
-      std::string str() const { return _str; }
-
-      StatFS& operator=(const Type);
-      StatFS& operator=(const std::string);
-
-      static Type        fromString(const std::string);
-      static std::string toString(const Type);
-
-    private:
-      StatFS();
-
-    private:
-      Type        _value;
-      std::string _str;
-    };
-
     class Create
     {
     public:
@@ -190,14 +157,12 @@ namespace mergerfs
 
   public:
     Policy() :
-      statfs(StatFS::SumUsedMaxFree),
       create(Create::ExistingPathMostFreeSpace),
       search(Search::FirstFound),
       action(Action::FirstFound)
     {}
 
   public:
-    StatFS statfs;
     Create create;
     Search search;
     Action action;

src/setxattr.cpp

@@ -75,15 +75,6 @@ _setxattr_controlfile(config::Config &config,
       else
         return -ENOSPC;
     }
-  else if(attrname == "user.mergerfs.statfs")
-    {
-      if((flags & XATTR_CREATE) == XATTR_CREATE)
-        return -EEXIST;
-      if(Policy::StatFS::fromString(attrval) != -1)
-        config.policy.statfs = attrval;
-      else
-        return -ENOSPC;
-    }
   else
     {
       return -ENOATTR;

src/statfs.cpp

@@ -68,24 +68,12 @@ _normalize_statvfs(struct statvfs      *fsstat,
 static
 void
 _merge_statvfs(struct statvfs       * const out,
-               const struct statvfs * const in,
-               const Policy::StatFS         policy)
+               const struct statvfs * const in)
 {
-  switch(policy)
+  if(out->f_bfree < in->f_bfree)
     {
-    case Policy::StatFS::SumUsedMaxFree:
-      if(out->f_bfree < in->f_bfree)
-        {
-          out->f_bfree  = in->f_bfree;
-          out->f_bavail = in->f_bavail;
-        }
-      break;
-
-    default:
-    case Policy::StatFS::SumUsedSumFree:
-      out->f_bfree  += in->f_bfree;
-      out->f_bavail += in->f_bavail;
-      break;
+      out->f_bfree  = in->f_bfree;
+      out->f_bavail = in->f_bavail;
     }
 
   out->f_ffree  += in->f_ffree;
@@ -96,8 +84,7 @@ _merge_statvfs(struct statvfs       * const out,
 
 static
 int
-_statfs(const Policy::StatFS  policy,
-        const vector<string> &srcmounts,
+_statfs(const vector<string> &srcmounts,
         struct statvfs       &fsstat)
 {
   unsigned long min_bsize   = ULONG_MAX;
@@ -134,7 +121,7 @@ _statfs(const Policy::StatFS  policy,
       for(;fsstatiter != endfsstatiter;++fsstatiter)
         {
           _normalize_statvfs(&fsstatiter->second,min_bsize,min_frsize,min_namemax);
-          _merge_statvfs(&fsstat,&fsstatiter->second,policy);
+          _merge_statvfs(&fsstat,&fsstatiter->second);
         }
     }
 
@@ -152,8 +139,7 @@ namespace mergerfs
       const ugid::SetResetGuard  uid;
       const config::Config      &config = config::get();
 
-      return _statfs(config.policy.statfs,
-                     config.srcmounts,
+      return _statfs(config.srcmounts,
                      *stat);
     }
   }

src/write.cpp

@@ -68,12 +68,6 @@ _process_kv(Config       &config,
       if(rv == 0)
         config.policy.create = value;
     }
-  else if(key == "statfs")
-    {
-      rv = (Policy::StatFS::fromString(value) != -1) ? 0 : -EINVAL;
-      if(rv == 0)
-        config.policy.statfs = value;
-    }
   else
     {
       rv = -EINVAL;