[PATCH] BKL shifting - ->rename()

Documentation/filesystems/Locking

@@ -61,7 +61,7 @@ symlink:	no	yes
 mkdir:		no	yes
 unlink:		no	yes (both)
 rmdir:		no	yes (both)	(see below)
-rename:		yes	yes (all)	(see below)
+rename:		no	yes (all)	(see below)
 readlink:	no	no
 follow_link:	no	no
 truncate:	no	yes		(see below)

Documentation/filesystems/porting

@@ -81,11 +81,11 @@ can relax your locking.
 [mandatory]
 
 ->lookup(), ->truncate(), ->create(), ->unlink(), ->mknod(), ->mkdir(),
-->rmdir(), ->link() and ->symlink() are called without BKL now.  Grab it
-on the entry, drop upon return - that will guarantee the same locking you
-used to have.  If your method or its parts do not need BKL - better yet,
-now you can shift lock_kernel() / unlock_kernel() so that they would protect
-exactly what needs to be protected.
+->rmdir(), ->link(), ->symlink() and ->rename() are called without BKL now.
+Grab it on the entry, drop upon return - that will guarantee the same
+locking you used to have.  If your method or its parts do not need BKL -
+better yet, now you can shift lock_kernel() / unlock_kernel() so that
+they would protect exactly what needs to be protected.
 
 ---
 [informational]

fs/affs/namei.c

@@ -462,6 +462,7 @@ affs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	struct buffer_head *bh = NULL;
 	int retval;
 
+	lock_kernel();
 	pr_debug("AFFS: rename(old=%u,\"%*s\" to new=%u,\"%*s\")\n",
 		 (u32)old_dir->i_ino, (int)old_dentry->d_name.len, old_dentry->d_name.name,
 		 (u32)new_dir->i_ino, (int)new_dentry->d_name.len, new_dentry->d_name.name);
@@ -472,9 +473,11 @@ affs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	/* Unlink destination if it already exists */
 	if (new_dentry->d_inode) {
 		retval = affs_remove_header(new_dentry);
-		if (retval)
+		if (retval) {
+			unlock_kernel();
 			return retval;
 		}
+	}
 
 	retval = -EIO;
 	bh = affs_bread(sb, old_dentry->d_inode->i_ino);
@@ -499,5 +502,6 @@ affs_rename(struct inode *old_dir, struct dentry *old_dentry,
 done:
 	mark_buffer_dirty_inode(bh, retval ? old_dir : new_dir);
 	affs_brelse(bh);
+	unlock_kernel();
 	return retval;
 }

fs/bfs/dir.c

@@ -213,6 +213,7 @@ static int bfs_rename(struct inode * old_dir, struct dentry * old_dentry,
 	if (S_ISDIR(old_inode->i_mode))
 		return -EINVAL;
 
+	lock_kernel();
 	old_bh = bfs_find_entry(old_dir, 
 				old_dentry->d_name.name, 
 				old_dentry->d_name.len, &old_de);
@@ -249,6 +250,7 @@ static int bfs_rename(struct inode * old_dir, struct dentry * old_dentry,
 	error = 0;
 
 end_rename:
+	unlock_kernel();
 	brelse(old_bh);
 	brelse(new_bh);
 	return error;

fs/coda/dir.c

@@ -501,6 +501,7 @@ static int coda_rename(struct inode *old_dir, struct dentry *old_dentry,
         int link_adjust = 0;
         int error;
 
+	lock_kernel();
 	coda_vfs_stat.rename++;
 
         CDEBUG(D_INODE, "old: %s, (%d length), new: %s"
@@ -527,6 +528,7 @@ static int coda_rename(struct inode *old_dir, struct dentry *old_dentry,
 	}
 
 	CDEBUG(D_INODE, "result %d\n", error); 
+	unlock_kernel();
 
 	return error;
 }

fs/ext2/namei.c

@@ -31,7 +31,6 @@
 
 #include "ext2.h"
 #include <linux/pagemap.h>
-#include <linux/smp_lock.h>
 
 /*
  * Couple of helper functions - make the code slightly cleaner.

fs/ext3/namei.c

@@ -1027,9 +1027,12 @@ static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry,
 
 	old_bh = new_bh = dir_bh = NULL;
 
+	lock_kernel();
 	handle = ext3_journal_start(old_dir, 2 * EXT3_DATA_TRANS_BLOCKS + 2);
-	if (IS_ERR(handle))
+	if (IS_ERR(handle)) {
+		unlock_kernel();
 		return PTR_ERR(handle);
+	}
 
 	if (IS_SYNC(old_dir) || IS_SYNC(new_dir))
 		handle->h_sync = 1;
@@ -1138,6 +1141,7 @@ static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry,
 	brelse (old_bh);
 	brelse (new_bh);
 	ext3_journal_stop(handle, old_dir);
+	unlock_kernel();
 	return retval;
 }
 
@@ -1153,5 +1157,5 @@ struct inode_operations ext3_dir_inode_operations = {
 	mkdir:		ext3_mkdir,
 	rmdir:		ext3_rmdir,
 	mknod:		ext3_mknod,
-	rename:		ext3_rename,		/* BKL held */
+	rename:		ext3_rename,
 };

fs/hfs/dir.c

@@ -376,20 +376,27 @@ int hfs_rmdir(struct inode * parent, struct dentry *dentry)
 int hfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	       struct inode *new_dir, struct dentry *new_dentry)
 {
-	struct hfs_cat_entry *old_parent = HFS_I(old_dir)->entry;
-	struct hfs_cat_entry *new_parent = HFS_I(new_dir)->entry;
+	struct hfs_cat_entry *old_parent;
+	struct hfs_cat_entry *new_parent;
 	struct hfs_cat_entry *victim = NULL;
 	struct hfs_cat_entry *deleted;
 	struct hfs_cat_key key;
 	int error;
 
+	lock_kernel();
+	old_parent = HFS_I(old_dir)->entry;
+	new_parent = HFS_I(new_dir)->entry;
 	if (build_key(&key, old_dir, old_dentry->d_name.name,
 		      old_dentry->d_name.len) ||
-	    (HFS_ITYPE(old_dir->i_ino) != HFS_ITYPE(new_dir->i_ino))) 
+	    (HFS_ITYPE(old_dir->i_ino) != HFS_ITYPE(new_dir->i_ino))) {
+		unlock_kernel();
 		return -EPERM;
+	}
 
-	if (!(victim = hfs_cat_get(old_parent->mdb, &key))) 
+	if (!(victim = hfs_cat_get(old_parent->mdb, &key))) {
+		unlock_kernel();
 		return -ENOENT;
+	}
 
 	error = -EPERM;
 	if (build_key(&key, new_dir, new_dentry->d_name.name,
@@ -418,5 +425,6 @@ int hfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 
 hfs_rename_put:
 	hfs_cat_put(victim);	/* Note that hfs_cat_put(NULL) is safe. */
+	unlock_kernel();
 	return error;
 }

fs/hfs/dir_dbl.c

@@ -366,6 +366,7 @@ static int dbl_rename(struct inode *old_dir, struct dentry *old_dentry,
 {
 	int error;
 
+	lock_kernel();
 	if (is_hdr(new_dir, new_dentry->d_name.name,
 		   new_dentry->d_name.len)) {
 		error = -EPERM;
@@ -378,6 +379,7 @@ static int dbl_rename(struct inode *old_dir, struct dentry *old_dentry,
 			error = -EPERM;
 		}
 	}
+	unlock_kernel();
 	return error;
 }
 

fs/hfs/dir_nat.c

@@ -425,9 +425,11 @@ static int nat_hdr_unlink(struct inode *dir, struct dentry *dentry)
 static int nat_hdr_rename(struct inode *old_dir, struct dentry *old_dentry,
 			  struct inode *new_dir, struct dentry *new_dentry)
 {
-	struct hfs_cat_entry *entry = HFS_I(old_dir)->entry;
+	struct hfs_cat_entry *entry;
 	int error = 0;
 
+	lock_kernel();
+	entry = HFS_I(old_dir)->entry;
 	if (!HFS_SB(old_dir->i_sb)->s_afpd) {
 		/* Not in AFPD compatibility mode */
 		error = -EPERM;
@@ -456,5 +458,6 @@ static int nat_hdr_rename(struct inode *old_dir, struct dentry *old_dentry,
 			error = -EPERM;
 		}
 	}
+	unlock_kernel();
 	return error;
 }

fs/hpfs/namei.c

@@ -482,6 +482,7 @@ int hpfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	err = 0;
 	hpfs_adjust_length((char *)old_name, &old_len);
 
+	lock_kernel();
 	hpfs_lock_3inodes(old_dir, new_dir, i);
 	
 	/* Erm? Moving over the empty non-busy directory is perfectly legal */
@@ -562,5 +563,6 @@ int hpfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	hpfs_decide_conv(i, (char *)new_name, new_len);
 	end1:
 	hpfs_unlock_3inodes(old_dir, new_dir, i);
+	unlock_kernel();
 	return err;
 }

fs/jffs/inode-v23.c

@@ -422,10 +422,12 @@ jffs_rename(struct inode *old_dir, struct dentry *old_dentry,
 		 old_dir, old_dentry->d_name.name,
 		 new_dir, new_dentry->d_name.name));
 
+	lock_kernel();
 	c = (struct jffs_control *)old_dir->i_sb->u.generic_sbp;
 	ASSERT(if (!c) {
 		printk(KERN_ERR "jffs_rename(): The old_dir inode "
 		       "didn't have a reference to a jffs_file struct\n");
+		unlock_kernel();
 		return -EIO;
 	});
 
@@ -544,6 +546,7 @@ jffs_rename(struct inode *old_dir, struct dentry *old_dentry,
 jffs_rename_end:
 	D3(printk (KERN_NOTICE "rename(): up biglock\n"));
 	up(&c->fmc->biglock);
+	unlock_kernel();
 	return result;
 } /* jffs_rename()  */
 

fs/jffs2/dir.c

@@ -978,9 +978,12 @@ static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry,
 	*/
 
 	/* Make a hard link */
+	lock_kernel();
 	ret = jffs2_do_link(old_dentry, new_dir_i, new_dentry, 1);
-	if (ret)
+	if (ret) {
+		unlock_kernel();
 		return ret;
+	}
 
 	/* Unlink the original */
 	ret = jffs2_do_unlink(old_dir_i, old_dentry, 1);
@@ -1001,6 +1004,7 @@ static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry,
 		}
 		
 	}
+	unlock_kernel();
 	return ret;
 }
 

fs/minix/namei.c

@@ -6,7 +6,6 @@
 
 #include <linux/fs.h>
 #include <linux/minix_fs.h>
-#include <linux/smp_lock.h>
 #include <linux/pagemap.h>
 
 static inline void inc_count(struct inode *inode)

fs/msdos/namei.c

@@ -561,6 +561,7 @@ int msdos_rename(struct inode *old_dir,struct dentry *old_dentry,
 	int is_hid,old_hid; /* if new file and old file are hidden */
 	char old_msdos_name[MSDOS_NAME], new_msdos_name[MSDOS_NAME];
 
+	lock_kernel();
 	error = msdos_format_name(old_dentry->d_name.name,
 				  old_dentry->d_name.len,old_msdos_name,
 				  &MSDOS_SB(old_dir->i_sb)->options);
@@ -584,6 +585,7 @@ int msdos_rename(struct inode *old_dir,struct dentry *old_dentry,
 	fat_brelse(sb, old_bh);
 
 rename_done:
+	unlock_kernel();
 	return error;
 }
 

fs/namei.c

@@ -1743,8 +1743,11 @@ int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
 			d_rehash(new_dentry);
 		dput(new_dentry);
 	}
-	if (!error)
+	if (!error) {
+		lock_kernel();
 		d_move(old_dentry,new_dentry);
+		unlock_kernel();
+	}
 	return error;
 }
 
@@ -1765,7 +1768,9 @@ int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry,
 	if (!error) {
 		/* The following d_move() should become unconditional */
 		if (!(old_dir->i_sb->s_type->fs_flags & FS_ODD_RENAME)) {
+			lock_kernel();
 			d_move(old_dentry, new_dentry);
+			unlock_kernel();
 		}
 	}
 	if (target)
@@ -1880,11 +1885,8 @@ static inline int do_rename(const char * oldname, const char * newname)
 	if (new_dentry == trap)
 		goto exit5;
 
-	lock_kernel();
 	error = vfs_rename(old_dir->d_inode, old_dentry,
 				   new_dir->d_inode, new_dentry);
-	unlock_kernel();
-
 exit5:
 	dput(new_dentry);
 exit4:

fs/ncpfs/dir.c

@@ -1035,6 +1035,7 @@ static int ncp_rename(struct inode *old_dir, struct dentry *old_dentry,
 		new_dentry->d_parent->d_name.name, new_dentry->d_name.name);
 
 	error = -EIO;
+	lock_kernel();
 	if (!ncp_conn_valid(server))
 		goto out;
 
@@ -1078,6 +1079,7 @@ static int ncp_rename(struct inode *old_dir, struct dentry *old_dentry,
 			break;
 	}
 out:
+	unlock_kernel();
 	return error;
 }
 

fs/nfs/dir.c

@@ -998,6 +998,7 @@ static int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	 * To prevent any new references to the target during the rename,
 	 * we unhash the dentry and free the inode in advance.
 	 */
+	lock_kernel();
 	if (!d_unhashed(new_dentry)) {
 		d_drop(new_dentry);
 		rehash = new_dentry;
@@ -1074,6 +1075,7 @@ static int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	/* new dentry created? */
 	if (dentry)
 		dput(dentry);
+	unlock_kernel();
 	return error;
 }
 

fs/reiserfs/namei.c

@@ -1101,13 +1101,17 @@ static int reiserfs_rename (struct inode * old_dir, struct dentry *old_dentry,
     // make sure, that oldname still exists and points to an object we
     // are going to rename
     old_de.de_gen_number_bit_string = 0;
+    lock_kernel();
     retval = reiserfs_find_entry (old_dir, old_dentry->d_name.name, old_dentry->d_name.len,
 				  &old_entry_path, &old_de);
     pathrelse (&old_entry_path);
-    if (retval == IO_ERROR)
+    if (retval == IO_ERROR) {
+	unlock_kernel();
 	return -EIO;
+    }
 
     if (retval != NAME_FOUND || old_de.de_objectid != old_inode->i_ino) {
+	unlock_kernel();
 	return -ENOENT;
     }
 
@@ -1118,6 +1122,7 @@ static int reiserfs_rename (struct inode * old_dir, struct dentry *old_dentry,
 
 	if (new_inode) {
 	    if (!reiserfs_empty_dir(new_inode)) {
+		unlock_kernel();
 		return -ENOTEMPTY;
 	    }
 	}
@@ -1128,13 +1133,17 @@ static int reiserfs_rename (struct inode * old_dir, struct dentry *old_dentry,
 	dot_dot_de.de_gen_number_bit_string = 0;
 	retval = reiserfs_find_entry (old_inode, "..", 2, &dot_dot_entry_path, &dot_dot_de);
 	pathrelse (&dot_dot_entry_path);
-	if (retval != NAME_FOUND)
+	if (retval != NAME_FOUND) {
+	    unlock_kernel();
 	    return -EIO;
+	}
 
 	/* inode number of .. must equal old_dir->i_ino */
-	if (dot_dot_de.de_objectid != old_dir->i_ino)
+	if (dot_dot_de.de_objectid != old_dir->i_ino) {
+	    unlock_kernel();
 	    return -EIO;
 	}
+    }
 
     journal_begin(&th, old_dir->i_sb, jbegin_count) ;
     windex = push_journal_writer("reiserfs_rename") ;
@@ -1152,6 +1161,7 @@ static int reiserfs_rename (struct inode * old_dir, struct dentry *old_dentry,
     } else if (retval) {
 	pop_journal_writer(windex) ;
 	journal_end(&th, old_dir->i_sb, jbegin_count) ;
+	unlock_kernel();
 	return retval;
     }
 
@@ -1298,6 +1308,7 @@ static int reiserfs_rename (struct inode * old_dir, struct dentry *old_dentry,
 
     pop_journal_writer(windex) ;
     journal_end(&th, old_dir->i_sb, jbegin_count) ;
+    unlock_kernel();
     return 0;
 }
 

fs/smbfs/dir.c

@@ -570,6 +570,7 @@ smb_rename(struct inode *old_dir, struct dentry *old_dentry,
 	 * Close any open files, and check whether to delete the
 	 * target before attempting the rename.
 	 */
+	lock_kernel();
 	if (old_dentry->d_inode)
 		smb_close(old_dentry->d_inode);
 	if (new_dentry->d_inode) {
@@ -592,5 +593,6 @@ smb_rename(struct inode *old_dir, struct dentry *old_dentry,
 		smb_renew_times(new_dentry);
 	}
 out:
+	unlock_kernel();
 	return error;
 }

fs/udf/namei.c

@@ -1167,6 +1167,7 @@ static int udf_rename (struct inode * old_dir, struct dentry * old_dentry,
 	struct buffer_head *dir_bh = NULL;
 	int retval = -ENOENT;
 
+	lock_kernel();
 	if ((ofi = udf_find_entry(old_dir, old_dentry, &ofibh, &ocfi)))
 	{
 		if (ofibh.sbh != ofibh.ebh)
@@ -1296,6 +1297,7 @@ static int udf_rename (struct inode * old_dir, struct dentry * old_dentry,
 			udf_release_data(nfibh.ebh);
 		udf_release_data(nfibh.sbh);
 	}
+	unlock_kernel();
 	return retval;
 }
 

fs/ufs/namei.c

@@ -282,6 +282,7 @@ static int ufs_rename (struct inode * old_dir, struct dentry * old_dentry,
 	struct ufs_dir_entry *old_de;
 	int err = -ENOENT;
 
+	lock_kernel();
 	old_de = ufs_find_entry (old_dentry, &old_bh);
 	if (!old_de)
 		goto out;
@@ -334,6 +335,7 @@ static int ufs_rename (struct inode * old_dir, struct dentry * old_dentry,
 		ufs_set_link(old_inode, dir_de, dir_bh, new_dir);
 		ufs_dec_count(old_dir);
 	}
+	unlock_kernel();
 	return 0;
 
 out_dir:
@@ -342,6 +344,7 @@ static int ufs_rename (struct inode * old_dir, struct dentry * old_dentry,
 out_old:
 	brelse (old_bh);
 out:
+	unlock_kernel();
 	return err;
 }
 

fs/vfat/namei.c

@@ -1199,6 +1199,7 @@ int vfat_rename(struct inode *old_dir,struct dentry *old_dentry,
 	old_bh = new_bh = dotdot_bh = NULL;
 	old_inode = old_dentry->d_inode;
 	new_inode = new_dentry->d_inode;
+	lock_kernel();
 	res = vfat_find(old_dir,&old_dentry->d_name,&old_sinfo,&old_bh,&old_de);
 	PRINTK3(("vfat_rename 2\n"));
 	if (res < 0) goto rename_done;
@@ -1265,6 +1266,7 @@ int vfat_rename(struct inode *old_dir,struct dentry *old_dentry,
 	fat_brelse(sb, dotdot_bh);
 	fat_brelse(sb, old_bh);
 	fat_brelse(sb, new_bh);
+	unlock_kernel();
 	return res;
 
 }