[PATCH] hfs: set correct create date for links

HFS+ also requires the correct creation date so recent version of OS X
recognize it as link.
Improve link handling:
- if something is wrong with the link, ignore the link attribute and treat
  it as regular file (this also fixes a missing unlock during lookup).
- check for incorrect link counts during unlink.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/hfsplus/catalog.c

@@ -127,6 +127,7 @@ static int hfsplus_cat_build_record(hfsplus_cat_entry *entry, u32 cnid, struct i
 			file->user_info.fdType = cpu_to_be32(HFSP_HARDLINK_TYPE);
 			file->user_info.fdCreator = cpu_to_be32(HFSP_HFSPLUS_CREATOR);
 			file->user_info.fdFlags = cpu_to_be16(0x100);
+			file->create_date = HFSPLUS_I(HFSPLUS_SB(inode->i_sb).hidden_dir).create_date;
 			file->permissions.dev = cpu_to_be32(HFSPLUS_I(inode).dev);
 		}
 		return sizeof(*file);

fs/hfsplus/dir.c

@@ -66,21 +66,28 @@ static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry,
 		}
 		cnid = be32_to_cpu(entry.file.id);
 		if (entry.file.user_info.fdType == cpu_to_be32(HFSP_HARDLINK_TYPE) &&
-		    entry.file.user_info.fdCreator == cpu_to_be32(HFSP_HFSPLUS_CREATOR)) {
+		    entry.file.user_info.fdCreator == cpu_to_be32(HFSP_HFSPLUS_CREATOR) &&
+		    (entry.file.create_date == HFSPLUS_I(HFSPLUS_SB(sb).hidden_dir).create_date ||
+		     entry.file.create_date == HFSPLUS_I(sb->s_root->d_inode).create_date) &&
+		    HFSPLUS_SB(sb).hidden_dir) {
 			struct qstr str;
 			char name[32];
 
 			if (dentry->d_fsdata) {
-				err = -ENOENT;
-				inode = NULL;
-				goto out;
+				/*
+				 * We found a link pointing to another link,
+				 * so ignore it and treat it as regular file.
+				 */
+				cnid = (unsigned long)dentry->d_fsdata;
+				linkid = 0;
+			} else {
+				dentry->d_fsdata = (void *)(unsigned long)cnid;
+				linkid = be32_to_cpu(entry.file.permissions.dev);
+				str.len = sprintf(name, "iNode%d", linkid);
+				str.name = name;
+				hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_SB(sb).hidden_dir->i_ino, &str);
+				goto again;
 			}
-			dentry->d_fsdata = (void *)(unsigned long)cnid;
-			linkid = be32_to_cpu(entry.file.permissions.dev);
-			str.len = sprintf(name, "iNode%d", linkid);
-			str.name = name;
-			hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_SB(sb).hidden_dir->i_ino, &str);
-			goto again;
 		} else if (!dentry->d_fsdata)
 			dentry->d_fsdata = (void *)(unsigned long)cnid;
 	} else {
@@ -330,7 +337,8 @@ static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
 	if (res)
 		return res;
 
-	inode->i_nlink--;
+	if (inode->i_nlink > 0)
+		inode->i_nlink--;
 	hfsplus_delete_inode(inode);
 	if (inode->i_ino != cnid && !inode->i_nlink) {
 		if (!atomic_read(&HFSPLUS_I(inode).opencnt)) {
@@ -339,7 +347,8 @@ static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
 				hfsplus_delete_inode(inode);
 		} else
 			inode->i_flags |= S_DEAD;
-	}
+	} else
+		inode->i_nlink = 0;
 	inode->i_ctime = CURRENT_TIME_SEC;
 	mark_inode_dirty(inode);