[PATCH] ext4: 48bit i_file_acl

As we are planning to support 48-bit block numbers for ext4, we need to
support 48-bit block numbers for extended attributes.  In the short term, we
can do this by reuse (on-disk) 16-bit padding (linux2.i_pad1 currently used
only by "hurd") as high order bits for xattr.  This patch basically does that.

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 14 insertions, 2 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 2b81b1324a6f..9db8cff3baa4 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2643,6 +2643,11 @@ void ext4_read_inode(struct inode * inode)
         ei->i_frag_size = raw_inode->i_fsize;
 #endif
         ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
+        if ((sizeof(sector_t) > 4) &&
+            (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
+             cpu_to_le32(EXT4_OS_HURD)))
+                ei->i_file_acl |=
+                        ((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32;
         if (!S_ISREG(inode->i_mode)) {
                 ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl);
         } else {
@@ -2776,6 +2781,11 @@ static int ext4_do_update_inode(handle_t *handle,
         raw_inode->i_frag = ei->i_frag_no;
         raw_inode->i_fsize = ei->i_frag_size;
 #endif
+        if ((sizeof(sector_t) > 4) &&
+            (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
+             cpu_to_le32(EXT4_OS_HURD)))
+                raw_inode->i_file_acl_high =
+                        cpu_to_le16(ei->i_file_acl >> 32);
         raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl);
         if (!S_ISREG(inode->i_mode)) {
                 raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl);
diff --git a/include/linux/ext4_fs.h b/include/linux/ext4_fs.h
index e952c6db9690..63ed89f5b27b 100644
--- a/include/linux/ext4_fs.h
+++ b/include/linux/ext4_fs.h
@@ -298,7 +298,7 @@ struct ext4_inode {
                 struct {
                         __u8    l_i_frag;       /* Fragment number */
                         __u8    l_i_fsize;      /* Fragment size */
-                        __u16   i_pad1;
+                        __le16  l_i_file_acl_high;
                         __le16  l_i_uid_high;   /* these 2 fields    */
                         __le16  l_i_gid_high;   /* were reserved2[0] */
                         __u32   l_i_reserved2;
@@ -314,7 +314,7 @@ struct ext4_inode {
                 struct {
                         __u8    m_i_frag;       /* Fragment number */
                         __u8    m_i_fsize;      /* Fragment size */
-                        __u16   m_pad1;
+                        __le16  m_i_file_acl_high;
                         __u32   m_i_reserved2[2];
                 } masix2;
         } osd2;                         /* OS dependent 2 */
@@ -328,6 +328,7 @@ struct ext4_inode {
 #define i_reserved1     osd1.linux1.l_i_reserved1
 #define i_frag          osd2.linux2.l_i_frag
 #define i_fsize         osd2.linux2.l_i_fsize
+#define i_file_acl_high osd2.linux2.l_i_file_acl_high
 #define i_uid_low       i_uid
 #define i_gid_low       i_gid
 #define i_uid_high      osd2.linux2.l_i_uid_high
@@ -348,6 +349,7 @@ struct ext4_inode {
 #define i_reserved1     osd1.masix1.m_i_reserved1
 #define i_frag          osd2.masix2.m_i_frag
 #define i_fsize         osd2.masix2.m_i_fsize
+#define i_file_acl_high osd2.masix2.m_i_file_acl_high
 #define i_reserved2     osd2.masix2.m_i_reserved2
 
 #endif /* defined(__KERNEL__) || defined(__linux__) */