Merge tag 'vfs-6.12-rc6.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs

Pull filesystem fixes from Christian Brauner:
 "VFS:

   - Fix copy_page_from_iter_atomic() if KMAP_LOCAL_FORCE_MAP=y is set

   - Add a get_tree_bdev_flags() helper that allows to modify e.g.,
     whether errors are logged into the filesystem context during
     superblock creation. This is used by erofs to fix a userspace
     regression where an error is currently logged when its used on a
     regular file which is an new allowed mode in erofs.

  netfs:

   - Fix the sysfs debug path in the documentation.

   - Fix iov_iter_get_pages*() for folio queues by skipping the page
     extracation if we're at the end of a folio.

  afs:

   - Fix moving subdirectories to different parent directory.

  autofs:

   - Fix handling of AUTOFS_DEV_IOCTL_TIMEOUT_CMD ioctl in
     validate_dev_ioctl(). The actual ioctl number, not the ioctl
     command needs to be checked for autofs"

* tag 'vfs-6.12-rc6.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs:
  iov_iter: fix copy_page_from_iter_atomic() if KMAP_LOCAL_FORCE_MAP
  autofs: fix thinko in validate_dev_ioctl()
  iov_iter: Fix iov_iter_get_pages*() for folio_queue
  afs: Fix missing subdir edit when renamed between parent dirs
  doc: correcting the debug path for cachefiles
  erofs: use get_tree_bdev_flags() to avoid misleading messages
  fs/super.c: introduce get_tree_bdev_flags()

3 files changed, 116 insertions, 2 deletions

diff --git a/fs/afs/dir.c b/fs/afs/dir.c
index f8622ed72e08..ada363af5aab 100644
--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -12,6 +12,7 @@
 #include <linux/swap.h>
 #include <linux/ctype.h>
 #include <linux/sched.h>
+#include <linux/iversion.h>
 #include <linux/task_io_accounting_ops.h>
 #include "internal.h"
 #include "afs_fs.h"
@@ -1823,6 +1824,8 @@ error:
 
 static void afs_rename_success(struct afs_operation *op)
 {
+	struct afs_vnode *vnode = AFS_FS_I(d_inode(op->dentry));
+
 	_enter("op=%08x", op->debug_id);
 
 	op->ctime = op->file[0].scb.status.mtime_client;
@@ -1832,6 +1835,22 @@ static void afs_rename_success(struct afs_operation *op)
 		op->ctime = op->file[1].scb.status.mtime_client;
 		afs_vnode_commit_status(op, &op->file[1]);
 	}
+
+	/* If we're moving a subdir between dirs, we need to update
+	 * its DV counter too as the ".." will be altered.
+	 */
+	if (S_ISDIR(vnode->netfs.inode.i_mode) &&
+	    op->file[0].vnode != op->file[1].vnode) {
+		u64 new_dv;
+
+		write_seqlock(&vnode->cb_lock);
+
+		new_dv = vnode->status.data_version + 1;
+		vnode->status.data_version = new_dv;
+		inode_set_iversion_raw(&vnode->netfs.inode, new_dv);
+
+		write_sequnlock(&vnode->cb_lock);
+	}
 }
 
 static void afs_rename_edit_dir(struct afs_operation *op)
@@ -1873,6 +1892,12 @@ static void afs_rename_edit_dir(struct afs_operation *op)
 				 &vnode->fid, afs_edit_dir_for_rename_2);
 	}
 
+	if (S_ISDIR(vnode->netfs.inode.i_mode) &&
+	    new_dvnode != orig_dvnode &&
+	    test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
+		afs_edit_dir_update_dotdot(vnode, new_dvnode,
+					   afs_edit_dir_for_rename_sub);
+
 	new_inode = d_inode(new_dentry);
 	if (new_inode) {
 		spin_lock(&new_inode->i_lock);
diff --git a/fs/afs/dir_edit.c b/fs/afs/dir_edit.c
index a71bff10496b..fe223fb78111 100644
--- a/fs/afs/dir_edit.c
+++ b/fs/afs/dir_edit.c
@@ -127,10 +127,10 @@ static struct folio *afs_dir_get_folio(struct afs_vnode *vnode, pgoff_t index)
 /*
  * Scan a directory block looking for a dirent of the right name.
  */
-static int afs_dir_scan_block(union afs_xdr_dir_block *block, struct qstr *name,
+static int afs_dir_scan_block(const union afs_xdr_dir_block *block, const struct qstr *name,
 			      unsigned int blocknum)
 {
-	union afs_xdr_dirent *de;
+	const union afs_xdr_dirent *de;
 	u64 bitmap;
 	int d, len, n;
 
@@ -492,3 +492,90 @@ error:
 	clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
 	goto out_unmap;
 }
+
+/*
+ * Edit a subdirectory that has been moved between directories to update the
+ * ".." entry.
+ */
+void afs_edit_dir_update_dotdot(struct afs_vnode *vnode, struct afs_vnode *new_dvnode,
+				enum afs_edit_dir_reason why)
+{
+	union afs_xdr_dir_block *block;
+	union afs_xdr_dirent *de;
+	struct folio *folio;
+	unsigned int nr_blocks, b;
+	pgoff_t index;
+	loff_t i_size;
+	int slot;
+
+	_enter("");
+
+	i_size = i_size_read(&vnode->netfs.inode);
+	if (i_size < AFS_DIR_BLOCK_SIZE) {
+		clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
+		return;
+	}
+	nr_blocks = i_size / AFS_DIR_BLOCK_SIZE;
+
+	/* Find a block that has sufficient slots available.  Each folio
+	 * contains two or more directory blocks.
+	 */
+	for (b = 0; b < nr_blocks; b++) {
+		index = b / AFS_DIR_BLOCKS_PER_PAGE;
+		folio = afs_dir_get_folio(vnode, index);
+		if (!folio)
+			goto error;
+
+		block = kmap_local_folio(folio, b * AFS_DIR_BLOCK_SIZE - folio_pos(folio));
+
+		/* Abandon the edit if we got a callback break. */
+		if (!test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
+			goto invalidated;
+
+		slot = afs_dir_scan_block(block, &dotdot_name, b);
+		if (slot >= 0)
+			goto found_dirent;
+
+		kunmap_local(block);
+		folio_unlock(folio);
+		folio_put(folio);
+	}
+
+	/* Didn't find the dirent to clobber.  Download the directory again. */
+	trace_afs_edit_dir(vnode, why, afs_edit_dir_update_nodd,
+			   0, 0, 0, 0, "..");
+	clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
+	goto out;
+
+found_dirent:
+	de = &block->dirents[slot];
+	de->u.vnode  = htonl(new_dvnode->fid.vnode);
+	de->u.unique = htonl(new_dvnode->fid.unique);
+
+	trace_afs_edit_dir(vnode, why, afs_edit_dir_update_dd, b, slot,
+			   ntohl(de->u.vnode), ntohl(de->u.unique), "..");
+
+	kunmap_local(block);
+	folio_unlock(folio);
+	folio_put(folio);
+	inode_set_iversion_raw(&vnode->netfs.inode, vnode->status.data_version);
+
+out:
+	_leave("");
+	return;
+
+invalidated:
+	kunmap_local(block);
+	folio_unlock(folio);
+	folio_put(folio);
+	trace_afs_edit_dir(vnode, why, afs_edit_dir_update_inval,
+			   0, 0, 0, 0, "..");
+	clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
+	goto out;
+
+error:
+	trace_afs_edit_dir(vnode, why, afs_edit_dir_update_error,
+			   0, 0, 0, 0, "..");
+	clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
+	goto out;
+}
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 52aab09a32a9..c9d620175e80 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -1073,6 +1073,8 @@ extern void afs_check_for_remote_deletion(struct afs_operation *);
 extern void afs_edit_dir_add(struct afs_vnode *, struct qstr *, struct afs_fid *,
 			     enum afs_edit_dir_reason);
 extern void afs_edit_dir_remove(struct afs_vnode *, struct qstr *, enum afs_edit_dir_reason);
+void afs_edit_dir_update_dotdot(struct afs_vnode *vnode, struct afs_vnode *new_dvnode,
+				enum afs_edit_dir_reason why);
 
 /*
  * dir_silly.c