hfsplus-implement-attributes-files-header-node-initialization-code-v2

* SETOFFSET macro was removed (Andrew Morton).
* Record offsets logic was reworked in hfsplus_init_header_node() (Al Viro).
* AttributesFile's header node's bitmap is initialized by memset() (Al Viro).
* Logic of checking attributes tree state before AttributesFile
  creation was reworked for HFSPLUS_CREATING_ATTR_TREE case (Andrew Morton).
* Setting error code was added after read_mapping_page()
  call in hfsplus_create_attributes_file() method (Andrew Morton).

Signed-off-by: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Hin-Tak Leung <htl10@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/fs/hfsplus/xattr.c b/fs/hfsplus/xattr.c
index 31f70f55a0f2b2da157d234d9370873cd4519c07..568a45cb114588cd498b841692678553e960e08c 100644 (file)
--- a/fs/hfsplus/xattr.c
+++ b/fs/hfsplus/xattr.c
@@ -127,9 +127,6 @@ static int can_set_xattr(struct inode *inode, const char *name,
        return 0;
 }
 
-#define SETOFFSET(buf, ndsiz, offset, rec) \
-       (*(u16 *)((u8 *)(buf) + (ndsiz) + (-2 * (rec))) = (cpu_to_be16(offset)))
-
 static void hfsplus_init_header_node(struct inode *attr_file,
                                        u32 clump_size,
                                        char *buf, size_t node_size)
@@ -137,18 +134,23 @@ static void hfsplus_init_header_node(struct inode *attr_file,
        struct hfs_bnode_desc *desc;
        struct hfs_btree_header_rec *head;
        u16 offset;
+       __be16 *rec_offsets;
        u32 hdr_node_map_rec_bits;
        char *bmp;
-       u32 temp;
+       u32 used_nodes;
+       u32 used_bmp_bytes;
 
        hfs_dbg(ATTR_MOD, "init_hdr_attr_file: clump %u, node_size %zu\n",
                                clump_size, node_size);
 
+       /* The end of the node contains list of record offsets */
+       rec_offsets = (__be16 *)(buf + node_size);
+
        desc = (struct hfs_bnode_desc *)buf;
        desc->type = HFS_NODE_HEADER;
        desc->num_recs = cpu_to_be16(HFSPLUS_BTREE_HDR_NODE_RECS_COUNT);
        offset = sizeof(struct hfs_bnode_desc);
-       SETOFFSET(buf, node_size, offset, 1);
+       *--rec_offsets = cpu_to_be16(offset);
 
        head = (struct hfs_btree_header_rec *)(buf + offset);
        head->node_size = cpu_to_be16(node_size);
@@ -158,10 +160,9 @@ static void hfsplus_init_header_node(struct inode *attr_file,
        head->attributes |= cpu_to_be32(HFS_TREE_BIGKEYS | HFS_TREE_VARIDXKEYS);
        head->max_key_len = cpu_to_be16(HFSPLUS_ATTR_KEYLEN - sizeof(u16));
        offset += sizeof(struct hfs_btree_header_rec);
-       SETOFFSET(buf, node_size, offset, 2);
-
+       *--rec_offsets = cpu_to_be16(offset);
        offset += HFSPLUS_BTREE_HDR_USER_BYTES;
-       SETOFFSET(buf, node_size, offset, 3);
+       *--rec_offsets = cpu_to_be16(offset);
 
        hdr_node_map_rec_bits = 8 * (node_size - offset - (4 * sizeof(u16)));
        if (be32_to_cpu(head->node_count) > hdr_node_map_rec_bits) {
@@ -178,16 +179,17 @@ static void hfsplus_init_header_node(struct inode *attr_file,
        }
 
        bmp = buf + offset;
-       temp = be32_to_cpu(head->node_count) - be32_to_cpu(head->free_nodes);
-
-       /* Working a byte at a time is endian safe */
-       while (temp >= 8) {
-               *bmp = 0xFF; temp -= 8; bmp++;
+       used_nodes =
+               be32_to_cpu(head->node_count) - be32_to_cpu(head->free_nodes);
+       used_bmp_bytes = used_nodes / 8;
+       if (used_bmp_bytes) {
+               memset(bmp, 0xFF, used_bmp_bytes);
+               bmp += used_bmp_bytes;
+               used_nodes %= 8;
        }
-       *bmp = ~(0xFF >> temp);
+       *bmp = ~(0xFF >> used_nodes);
        offset += hdr_node_map_rec_bits / 8;
-
-       SETOFFSET(buf, node_size, offset, 4);
+       *--rec_offsets = cpu_to_be16(offset);
 }
 
 int __hfsplus_setxattr(struct inode *inode, const char *name,