bugfix: fix cross-subvolume rename failure on bcachefs (#527)

andy5995 · web-flow · commit 2c10b72635c3 · 2026-04-28T11:49:34.000-05:00
* bugfix: fix cross-subvolume rename failure on bcachefs On bcachefs, subvolumes share the same st_dev (unlike btrfs), so rmw correctly matched the waste folder by device number but rename() still returned EXDEV when moving across subvolumes. Add a fallback to safe_mv_via_exec() when rename() fails with EXDEV on a same-device move. Also switch from BTRFS_IOC_CLONE (linux/btrfs.h) to the generic FICLONE ioctl (linux/fs.h), which is supported by any reflink-capable filesystem (btrfs, bcachefs, xfs, etc.), and update the meson header check accordingly. Add test/test_bcachefs.sh which creates an 8M bcachefs image on-the-fly, exercises cross-subvolume file and directory moves, and cleans up after itself. Skips gracefully when bcachefs kernel support is unavailable. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Fixes #526 * refactor/test: bcachefs test improvements and ficlone rename - test/COMMON: add SKIP=77 for Meson skip exit code - test/test_bcachefs.sh: use pre-existing image from test dir instead of creating one; skip if kernel bcachefs support or image is absent; guard against stale mounts/loop devices and leftover files from previous runs - .github/workflows/c-cpp.yml: add bcachefs image cache/download step - test/rmw-bcachefs-test.img.sha256sum: add checksum file for CI caching - man/rmw.1: add BTRFS AND BCACHEFS subsection under NOTES - Rename want_btrfs_clone option to want_ficlone - Rename HAVE_LINUX_BTRFS macro to HAVE_FICLONE - Rename has_btrfs_header variable to has_linux_fs_header - Rename src/btrfs.c and src/btrfs.h to src/ficlone.c and src/ficlone.h - Rename is_btrfs() to is_ficlone_fs() and do_btrfs_clone() to do_ficlone() - Rename is_btrfs struct field in st_waste to is_ficlone_fs Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * docs: update ChangeLog; note breaking meson option rename Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> --------- Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com> Fixes #526
diff --git a/.github/workflows/c-cpp.yml b/.github/workflows/c-cpp.yml
@@ -29,6 +29,8 @@ on:
 
 env:
   TERM: xterm
+  BTRFS_IMG: test/rmw-btrfs-test.img
+  BCACHEFS_IMG: test/rmw-bcachefs-test.img
 
 jobs:
   build:
@@ -180,14 +182,27 @@ jobs:
       uses: actions/cache@v5
       id: btrfs-img-cache
       with:
-        path: test/rmw-btrfs-test.img
+        path: ${{ env.BTRFS_IMG }}
         key: ${{ hashFiles('test/rmw-btrfs-test.img.sha256sum') }}
 
     - if: ${{ steps.btrfs-img-cache.outputs.cache-hit != 'true' }}
-      run: curl -L -o test/rmw-btrfs-test.img 'https://www.dropbox.com/scl/fi/57g3ixd3w3tuz4qoc2zp1/rmw-btrfs-test.img?rlkey=yc7krtntswsa1bwz0sbugy4gi&st=hkgrht05&dl=0'
+      run: curl -L -o "$BTRFS_IMG" 'https://www.dropbox.com/scl/fi/57g3ixd3w3tuz4qoc2zp1/rmw-btrfs-test.img?rlkey=yc7krtntswsa1bwz0sbugy4gi&st=hkgrht05&dl=0'
 
     - name: Test btrfs image existence
-      run: test -f test/rmw-btrfs-test.img
+      run: test -f "$BTRFS_IMG"
+
+    - name: Cache bcachefs Image
+      uses: actions/cache@v5
+      id: bcachefs-img-cache
+      with:
+        path: ${{ env.BCACHEFS_IMG }}
+        key: ${{ hashFiles('test/rmw-bcachefs-test.img.sha256sum') }}
+
+    - if: ${{ steps.bcachefs-img-cache.outputs.cache-hit != 'true' }}
+      run: curl -L -o "$BCACHEFS_IMG" 'https://www.dropbox.com/scl/fi/key20cj08ca9engqt5kzi/rmw-bcachefs-test.img?rlkey=th6zw1ar7t0dy9m7qzah5wvq9&st=nrwczcqn&dl=0'
+
+    - name: Test bcachefs image existence
+      run: test -f "$BCACHEFS_IMG"
 
     - name: Install Dependencies
       run: |
diff --git a/.gitignore b/.gitignore
@@ -17,3 +17,4 @@ subprojects/**
 !subprojects/**/*.wrap
 /packaging/appimage/.env
 /test/rmw-btrfs-test.img
+/test/rmw-bcachefs-test.img
diff --git a/ChangeLog b/ChangeLog
@@ -1,4 +1,19 @@
 
+rmw (in-progress):
+  * BREAKING: The meson build option `want_btrfs_clone` has been renamed to
+    `want_ficlone`. Update any build scripts that pass `-Dwant_btrfs_clone=`
+    to use `-Dwant_ficlone=` instead.
+  * refactor: Rename btrfs.c/btrfs.h to ficlone.c/ficlone.h; rename
+    do_btrfs_clone() to do_ficlone() and is_btrfs() to is_ficlone_fs();
+    rename HAVE_LINUX_BTRFS macro to HAVE_FICLONE
+  * Add bcachefs test (test_bcachefs.sh); uses a pre-existing image and
+    skips if kernel bcachefs support or the image is absent
+  * docs: Add BTRFS AND BCACHEFS section to man page
+  * bugfix: Fix "Invalid cross-device link" error on bcachefs when source and
+    waste folder are on separate subvolumes (#526); use generic FICLONE ioctl
+    (linux/fs.h) instead of BTRFS_IOC_CLONE, and fall back to 'mv' when
+    rename() returns EXDEV on a same-device move
+
 2026-04-07
 
 - rmw 0.9.5:
diff --git a/README.md b/README.md
@@ -1,4 +1,4 @@
-# rmw-0.9.5
+# rmw-0.10.0-dev
 ## Description
 
 rmw (ReMove to Waste) is a trashcan/recycle bin utility for the command line.
diff --git a/man/rmw.1 b/man/rmw.1
@@ -192,6 +192,17 @@ directory will not be used for the current run of rmw.
 With the media mounted, once you manually create the waste directory
 for that device (e.g. "/mnt/flash/.Trash-$UID") and run rmw, it will
 automatically create the two required child directories "files" and "info".
+.SS BTRFS AND BCACHEFS
+rmw supports moving files across subvolumes on btrfs and bcachefs
+filesystems. Because the kernel treats subvolumes as separate
+filesystems, a cross-subvolume move would normally fail; rmw detects
+this case and performs a copy-then-delete instead, preserving the
+expected trash semantics.
+
+To use this feature, define a WASTE directory on the destination
+subvolume in your configuration file. For example, if your waste
+directory is on a different subvolume than the files you want to
+remove, rmw will handle the move transparently.
 .SH EXAMPLES
 .SS RESTORING
 rmw -z ~/.local/share/Waste/files/foo
diff --git a/meson.build b/meson.build
@@ -1,7 +1,7 @@
 project(
   'rmw',
   'c',
-  version: '0.9.5',
+  version: '0.10.0-dev',
   meson_version: '>= 0.59.0',
   default_options: [
     'c_std=gnu99',
diff --git a/meson_options.txt b/meson_options.txt
@@ -1,10 +1,10 @@
 option('build_tests', type : 'boolean', value : true,
        description : 'build tests')
 option(
-    'want_btrfs_clone',
+    'want_ficlone',
     type : 'boolean',
     value: 'true',
-    description: 'Include support for cloning files between btrfs root volumes and subvolumes')
+    description: 'Include support for cloning files between subvolumes using FICLONE (btrfs, bcachefs, xfs, etc.)')
 option('nls', type : 'boolean', value : true,
        description : 'include native language support (install translations)')
 
diff --git a/src/config_rmw.c b/src/config_rmw.c
@@ -20,7 +20,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include <unistd.h>
 
-#include "btrfs.h"
+#include "ficlone.h"
 #include "config_rmw.h"
 #include "utils.h"
 #include "main.h"
@@ -275,7 +275,7 @@ parse_line_waste(st_waste *waste_curr, struct Canfigger *node,
   else if (p_state == -1)
     exit(p_state);
 
-  waste_curr->is_btrfs = is_btrfs(waste_curr->parent);
+  waste_curr->is_ficlone_fs = is_ficlone_fs(waste_curr->parent);
 
   // get device number to use later for rename
   struct stat st, mp_st;
diff --git a/src/ficlone.c b/src/ficlone.c
@@ -23,22 +23,22 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "globals.h"
 #endif
 
-#ifdef HAVE_LINUX_BTRFS
+#ifdef HAVE_FICLONE
 #include <fcntl.h>
-#include <linux/btrfs.h>
+#include <linux/fs.h>
 #include <sys/ioctl.h>
 #include <sys/statfs.h>
 #include <sys/stat.h>
 #include <unistd.h>
 #endif
 
-#include "btrfs.h"
+#include "ficlone.h"
 #include "messages.h"
 
 bool
-is_btrfs(const char *path)
+is_ficlone_fs(const char *path)
 {
-#ifdef HAVE_LINUX_BTRFS
+#ifdef HAVE_FICLONE
   struct statfs buf;
 
   if (statfs(path, &buf) == -1)
@@ -57,9 +57,9 @@ is_btrfs(const char *path)
 
 
 int
-do_btrfs_clone(const char *source, const char *dest, int *save_errno)
+do_ficlone(const char *source, const char *dest, int *save_errno)
 {
-#ifdef HAVE_LINUX_BTRFS
+#ifdef HAVE_FICLONE
   int src_fd, dest_fd;
   struct stat src_stat;
 
@@ -91,7 +91,7 @@ do_btrfs_clone(const char *source, const char *dest, int *save_errno)
     return dest_fd;
   }
 
-  int res = ioctl(dest_fd, BTRFS_IOC_CLONE, src_fd);
+  int res = ioctl(dest_fd, FICLONE, src_fd);
   *save_errno = errno;
 
   close(src_fd);
diff --git a/src/ficlone.h b/src/ficlone.h
@@ -18,15 +18,15 @@ You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#ifndef _INC_BTRFS_H
-#define _INC_BTRFS_H
+#ifndef _INC_FICLONE_H
+#define _INC_FICLONE_H
 
 #include <stdbool.h>
 
 #define BTRFS_SUPER_MAGIC 0x9123683E
 
-bool is_btrfs(const char *path);
+bool is_ficlone_fs(const char *path);
 
-int do_btrfs_clone(const char *source, const char *dest, int *save_errno);
+int do_ficlone(const char *source, const char *dest, int *save_errno);
 
 #endif
diff --git a/src/main.c b/src/main.c
@@ -26,7 +26,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "purging.h"
 #include "strings_rmw.h"
 #include "messages.h"
-#include "btrfs.h"
+#include "ficlone.h"
 #include "trashinfo.h"
 
 
@@ -387,7 +387,7 @@ damage of 5000 hp. You feel satisfied.\n"));
     while (waste_curr != NULL)
     {
       if (waste_curr->dev_num == st_target.dev_num ||
-          (waste_curr->is_btrfs && is_btrfs(argv[file_arg])))
+          (waste_curr->is_ficlone_fs && is_ficlone_fs(argv[file_arg])))
       {
         char *tmp_str = join_paths(waste_curr->files, st_target.base_name);
         // *st_target.waste_dest_name = '\0';
@@ -421,7 +421,7 @@ damage of 5000 hp. You feel satisfied.\n"));
             if (!S_ISDIR(st_file_arg.st_mode))
             {
               /* attempt btrfs clone if not a directory */
-              r_result = do_btrfs_clone(src, dst, &save_errno);
+              r_result = do_ficlone(src, dst, &save_errno);
               errno = save_errno;
             }
             else
@@ -448,7 +448,13 @@ damage of 5000 hp. You feel satisfied.\n"));
           {
             /* same device: simple rename */
             r_result = rename(src, dst);
-            /* rename sets errno on failure */
+            if (r_result != 0 && errno == EXDEV)
+            {
+              /* rename failed with EXDEV even though st_dev matched (e.g.,
+                 bcachefs cross-subvolume). Fall back to copy+delete. */
+              r_result = safe_mv_via_exec(src, dst, &save_errno);
+              errno = save_errno;
+            }
           }
         }
 
@@ -702,10 +708,10 @@ main(const int argc, char *const argv[])
     printf("PATH_MAX = %d\n", PATH_MAX);
 
   if (verbose > 0)
-#ifdef HAVE_LINUX_BTRFS
-    puts("btrfs_clone support: true");
+#ifdef HAVE_FICLONE
+    puts("ficlone support: true");
 #else
-    puts("btrfs_clone support: false");
+    puts("ficlone support: false");
 #endif
 
   const st_loc *st_location = get_locations(cli_user_options.alt_config_file);
diff --git a/src/meson.build b/src/meson.build
@@ -23,7 +23,7 @@ endif
 
 src = [
   'globals.c',
-  'btrfs.c',
+  'ficlone.c',
   'restore.c',
   'config_rmw.c',
   'parse_cli_options.c',
@@ -35,26 +35,26 @@ src = [
   'utils.c',
 ]
 
-# Used for btrfs functions
+# Used for FICLONE support
 has_statfs = false
-has_btrfs_header = false
+has_linux_fs_header = false
 if host_sys == 'linux'
-  if get_option('want_btrfs_clone')
+  if get_option('want_ficlone')
     has_statfs = cc.has_function(
       'statfs',
       prefix: '#include <sys/statfs.h>',
     )
-    has_btrfs_header = cc.has_header('linux/btrfs.h')
-    if has_statfs and has_btrfs_header
-      conf.set('HAVE_LINUX_BTRFS', 1)
+    has_linux_fs_header = cc.has_header('linux/fs.h')
+    if has_statfs and has_linux_fs_header
+      conf.set('HAVE_FICLONE', 1)
     else
       error(
         '''
 
-  : Requirements not met for btrfs clone support.
-  : If missing linux/btrfs.h, you probably need to install the linux-headers package.
-  : To build without btrfs clone support and skip this check, add
-  : "-Dwant_btrfs_clone=false" to the meson setup options.''',
+  : Requirements not met for reflink clone support.
+  : If missing linux/fs.h, you probably need to install the linux-headers package.
+  : To build without reflink clone support and skip this check, add
+  : "-Dwant_ficlone=false" to the meson setup options.''',
       )
     endif
   endif
diff --git a/src/restore.c b/src/restore.c
@@ -30,7 +30,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <unistd.h>
 
 #include "parse_cli_options.h"
-#include "btrfs.h"
+#include "ficlone.h"
 #include "restore.h"
 #include "utils.h"
 #include "messages.h"
@@ -108,7 +108,7 @@ move_back(const char *src, const char *dest, bool want_dry_run)
     else
     {
       /* regular file on different device -> try btrfs clone */
-      int clone_res = do_btrfs_clone(src, dest, &clone_errno);
+      int clone_res = do_ficlone(src, dest, &clone_errno);
       if (clone_res == 0)
       {
         errno = 0;
diff --git a/src/trashinfo.h b/src/trashinfo.h
@@ -67,7 +67,7 @@ struct st_waste
    */
   bool removable;
 
-  bool is_btrfs;
+  bool is_ficlone_fs;
 };
 
 
diff --git a/test/COMMON b/test/COMMON
@@ -1,6 +1,8 @@
 # shellcheck shell=sh
 # included by test scripts
 
+SKIP=77
+
 create_some_files() {
 mkdir -p somefiles/topdir/dir1/dir2/dir3
 
diff --git a/test/conf/bcachefs_img.testrc b/test/conf/bcachefs_img.testrc
@@ -0,0 +1,4 @@
+waste = /tmp/rmw-bcachefs-loop/@two/Waste
+WASTE = $HOME/.local/share/Waste
+
+expire_age = 45
diff --git a/test/meson.build b/test/meson.build
@@ -18,8 +18,11 @@ scripts = [
   'test_restore.sh',
 ]
 
-if has_statfs and has_btrfs_header
-  scripts += ['test_btrfs_clone.sh']
+if host_sys == 'linux'
+  if has_statfs and has_linux_fs_header
+    scripts += ['test_btrfs_clone.sh']
+  endif
+  scripts += ['test_bcachefs.sh']
 endif
 
 RMW_FAKE_HOME = join_paths(meson.current_build_dir(), 'rmw-tests-home')
@@ -54,4 +57,3 @@ foreach s : scripts
     depends: main_bin,
   )
 endforeach
-
diff --git a/test/rmw-bcachefs-test.img.sha256sum b/test/rmw-bcachefs-test.img.sha256sum
@@ -0,0 +1 @@
+bc7bcbd2800230995ba36394f1814e83bee2eeca579691420b7feeff653cbf7c  rmw-bcachefs-test.img
diff --git a/test/test_bcachefs.sh b/test/test_bcachefs.sh

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-# rmw-0.9.5`
	`1`	`+# rmw-0.10.0-dev`
`2`	`2`	`## Description`
`3`	`3`
`4`	`4`	`rmw (ReMove to Waste) is a trashcan/recycle bin utility for the command line.`