I found another problem in the msdos-fs rename code and have attached an
updated patch. There was a missing copy of the i_nlink value when
changing inodes for a cross-directories move; the default of 1 worked OK
for files but was disastrous for directories, sometimes resulting in
cyclical structures.
Regards,
Bill
--------------510853E233951EB21D204CF9
Content-Type: text/plain; charset=us-ascii; name="msdos_122-patch"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline; filename="msdos_122-patch"
--- linux-2.1.122/fs/msdos/namei.c.old Wed Sep 16 21:59:38 1998
+++ linux-2.1.122/fs/msdos/namei.c Fri Sep 18 15:28:55 1998
@@ -266,6 +266,7 @@
res = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &bh,
&de, &ino);
+
if (res == -ENOENT)
goto add;
if (res < 0)
@@ -275,7 +276,7 @@
/* try to get the inode */
res = -EACCES;
- inode = iget(dir->i_sb, ino);
+ inode = iget(sb, ino);
if (!inode)
goto out;
if (!inode->i_sb ||
@@ -289,9 +290,9 @@
iput(inode);
goto out;
}
- res = 0;
add:
d_add(dentry, inode);
+ res = 0;
out:
return res;
}
@@ -446,14 +447,14 @@
if (dir->i_dev != inode->i_dev || dir == inode)
printk("msdos_rmdir: impossible condition\n");
/*
- * Prune any child dentries, then verify that
- * the directory is empty and not in use.
+ * Check whether the directory is empty, then prune
+ * any child dentries and make sure it's not in use.
*/
- shrink_dcache_parent(dentry);
res = msdos_empty(inode);
if (res)
goto rmdir_done;
res = -EBUSY;
+ shrink_dcache_parent(dentry);
if (dentry->d_count > 1) {
#ifdef MSDOS_DEBUG
printk("msdos_rmdir: %s/%s busy, d_count=%d\n",
@@ -476,6 +477,7 @@
de->name[0] = DELETED_FLAG;
fat_mark_buffer_dirty(sb, bh, 1);
res = 0;
+
rmdir_done:
fat_brelse(sb, bh);
return res;
@@ -499,18 +501,21 @@
return res;
is_hid = (dentry->d_name.name[0]=='.') && (msdos_name[0]!='.');
fat_lock_creation();
- if (fat_scan(dir,msdos_name,&bh,&de,&ino,SCAN_ANY) >= 0) {
- fat_unlock_creation();
- /* N.B. does this need to be released on the other path? */
- fat_brelse(sb, bh);
- return -EEXIST;
- }
+ if (fat_scan(dir,msdos_name,&bh,&de,&ino,SCAN_ANY) >= 0)
+ goto out_exist;
+
res = msdos_create_entry(dir,msdos_name,1,is_hid, &inode);
if (res < 0)
goto out_unlock;
+
dir->i_nlink++;
inode->i_nlink = 2; /* no need to mark them dirty */
MSDOS_I(inode)->i_busy = 1; /* prevent lookups */
+ /*
+ * Instantiate the dentry now, in case we need to cleanup.
+ */
+ d_instantiate(dentry, inode);
+
if ((res = fat_add_cluster(inode)) < 0)
goto mkdir_error;
if ((res = msdos_create_entry(inode,MSDOS_DOT,1,0,&dot)) < 0)
@@ -521,9 +526,9 @@
dot->i_nlink = inode->i_nlink;
mark_inode_dirty(dot);
iput(dot);
+
if ((res = msdos_create_entry(inode,MSDOS_DOTDOT,1,0,&dot)) < 0)
goto mkdir_error;
- fat_unlock_creation();
dot->i_size = dir->i_size;
MSDOS_I(dot)->i_start = MSDOS_I(dir)->i_start;
MSDOS_I(dot)->i_logstart = MSDOS_I(dir)->i_logstart;
@@ -531,15 +536,22 @@
mark_inode_dirty(dot);
MSDOS_I(inode)->i_busy = 0;
iput(dot);
- d_instantiate(dentry, inode);
- return 0;
+ res = 0;
-mkdir_error:
- if (msdos_rmdir(dir,dentry) < 0)
- fat_fs_panic(dir->i_sb,"rmdir in mkdir failed");
out_unlock:
fat_unlock_creation();
return res;
+
+mkdir_error:
+ printk("msdos_mkdir: error=%d, attempting cleanup\n", res);
+ if (msdos_rmdir(dir,dentry) < 0)
+ fat_fs_panic(dir->i_sb,"rmdir in mkdir failed");
+ goto out_unlock;
+
+out_exist:
+ fat_brelse(sb, bh);
+ res = -EEXIST;
+ goto out_unlock;
}
/***** Unlink a file */
@@ -636,10 +648,14 @@
if ((old_de->attr & ATTR_SYS))
goto out_error;
+ if (S_ISDIR(new_inode->i_mode)) {
+ /* make sure it's empty */
+ error = msdos_empty(new_inode);
+ if (error)
+ goto out_error;
#ifdef MSDOS_CHECK_BUSY
- /* check for a busy dentry */
- error = -EBUSY;
- if (new_dentry->d_count > 1) {
+ /* check for a busy dentry */
+ error = -EBUSY;
shrink_dcache_parent(new_dentry);
if (new_dentry->d_count > 1) {
printk("msdos_rename_same: %s/%s busy, count=%d\n",
@@ -647,20 +663,19 @@
new_dentry->d_count);
goto out_error;
}
- }
#endif
-
- if (S_ISDIR(new_inode->i_mode)) {
new_dir->i_nlink--;
mark_inode_dirty(new_dir);
}
new_inode->i_nlink = 0;
MSDOS_I(new_inode)->i_busy = 1;
mark_inode_dirty(new_inode);
-#ifdef MSDOS_CHECK_BUSY
- /* d_delete the dentry, as we killed its inode */
- d_delete(new_dentry);
-#endif
+ /*
+ * Make it negative if it's not busy;
+ * otherwise let d_move() drop it.
+ */
+ if (new_dentry->d_count == 1)
+ d_delete(new_dentry);
new_de->name[0] = DELETED_FLAG;
fat_mark_buffer_dirty(sb, new_bh, 1);
@@ -763,16 +778,22 @@
}
#endif
if (S_ISDIR(new_inode->i_mode)) {
+ /* make sure it's empty */
+ error = msdos_empty(new_inode);
+ if (error)
+ goto out_new;
new_dir->i_nlink--;
mark_inode_dirty(new_dir);
}
new_inode->i_nlink = 0;
MSDOS_I(new_inode)->i_busy = 1;
mark_inode_dirty(new_inode);
-#ifdef MSDOS_CHECK_BUSY
- /* d_delete the dentry, as we killed its inode */
- d_delete(new_dentry);
-#endif
+ /*
+ * Make it negative if it's not busy;
+ * otherwise let d_move() drop it.
+ */
+ if (new_dentry->d_count == 1)
+ d_delete(new_dentry);
new_de->name[0] = DELETED_FLAG;
fat_mark_buffer_dirty(sb, new_bh, 1);
fat_brelse(sb, new_bh);
@@ -785,8 +806,13 @@
if (S_ISDIR(old_inode->i_mode)) {
error = fat_scan(old_inode, MSDOS_DOTDOT, &dotdot_bh,
&dotdot_de, &dotdot_ino, SCAN_ANY);
- if (error < 0)
+ if (error < 0) {
+ printk(KERN_WARNING
+ "MSDOS: %s/%s, get dotdot failed, ret=%d\n",
+ old_dentry->d_parent->d_name.name,
+ old_dentry->d_name.name, error);
goto rename_done;
+ }
error = -EIO;
dotdot_inode = iget(sb, dotdot_ino);
if (!dotdot_inode)
@@ -804,12 +830,19 @@
free_inode = iget(sb, free_ino);
if (!free_inode)
goto out_iput;
+ /* make sure it's not busy! */
+ if (MSDOS_I(free_inode)->i_busy)
+ printk(KERN_ERR "msdos_rename_diff: new inode %ld busy!\n",
+ (ino_t) free_ino);
+ if (!list_empty(&free_inode->i_dentry))
+ printk("msdos_rename_diff: free inode has aliases??\n");
msdos_read_inode(free_inode);
/*
* Make sure the old dentry isn't busy,
* as we need to change inodes ...
*/
+ error = -EBUSY;
if (old_dentry->d_count > 1) {
shrink_dcache_parent(old_dentry);
if (old_dentry->d_count > 1) {
@@ -825,6 +858,7 @@
d_delete(old_dentry);
free_inode->i_mode = old_inode->i_mode;
+ free_inode->i_nlink = old_inode->i_nlink;
free_inode->i_size = old_inode->i_size;
free_inode->i_blocks = old_inode->i_blocks;
free_inode->i_mtime = old_inode->i_mtime;
@@ -836,16 +870,21 @@
MSDOS_I(free_inode)->i_logstart = MSDOS_I(old_inode)->i_logstart;
MSDOS_I(free_inode)->i_attrs = MSDOS_I(old_inode)->i_attrs;
+ /* release the old inode's resources */
+ MSDOS_I(old_inode)->i_start = 0;
+ MSDOS_I(old_inode)->i_logstart = 0;
+ old_inode->i_nlink = 0;
+
/*
* Install the new inode ...
*/
d_instantiate(old_dentry, free_inode);
+ fat_mark_buffer_dirty(sb, free_bh, 1);
fat_cache_inval_inode(old_inode);
mark_inode_dirty(old_inode);
old_de->name[0] = DELETED_FLAG;
fat_mark_buffer_dirty(sb, old_bh, 1);
- fat_mark_buffer_dirty(sb, free_bh, 1);
iput(old_inode);
/* a directory? */
@@ -854,13 +893,13 @@
MSDOS_I(dotdot_inode)->i_logstart = MSDOS_I(new_dir)->i_logstart;
dotdot_de->start = CT_LE_W(MSDOS_I(new_dir)->i_logstart);
dotdot_de->starthi = CT_LE_W((MSDOS_I(new_dir)->i_logstart) >> 16);
- mark_inode_dirty(dotdot_inode);
- fat_mark_buffer_dirty(sb, dotdot_bh, 1);
old_dir->i_nlink--;
new_dir->i_nlink++;
/* no need to mark them dirty */
dotdot_inode->i_nlink = new_dir->i_nlink;
+ mark_inode_dirty(dotdot_inode);
iput(dotdot_inode);
+ fat_mark_buffer_dirty(sb, dotdot_bh, 1);
fat_brelse(sb, dotdot_bh);
}
--------------510853E233951EB21D204CF9--
-
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