ext4: optimize Hurd tests when reading/writing inodes

Set a in-memory superblock flag to indicate whether the file system is
designed to support the Hurd.

Also, add a sanity check to make sure the 64-bit feature is not set
for Hurd file systems, since i_file_acl_high conflicts with a
Hurd-specific field.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 3 insertions, 6 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index ed2c13a7f293..b5e182acf9b9 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4168,8 +4168,7 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
         EXT4_INODE_GET_XTIME(i_atime, inode, raw_inode);
         EXT4_EINODE_GET_XTIME(i_crtime, ei, raw_inode);
 
-        if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
-            cpu_to_le32(EXT4_OS_HURD)) {
+        if (likely(!test_opt2(inode->i_sb, HURD_COMPAT))) {
                 inode->i_version = le32_to_cpu(raw_inode->i_disk_version);
                 if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
                         if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi))
@@ -4345,8 +4344,7 @@ static int ext4_do_update_inode(handle_t *handle,
                 goto out_brelse;
         raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
         raw_inode->i_flags = cpu_to_le32(ei->i_flags & 0xFFFFFFFF);
-        if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
-            cpu_to_le32(EXT4_OS_HURD))
+        if (likely(!test_opt2(inode->i_sb, HURD_COMPAT)))
                 raw_inode->i_file_acl_high =
                         cpu_to_le16(ei->i_file_acl >> 32);
         raw_inode->i_file_acl_lo = cpu_to_le32(ei->i_file_acl);
@@ -4391,8 +4389,7 @@ static int ext4_do_update_inode(handle_t *handle,
                         raw_inode->i_block[block] = ei->i_data[block];
         }
 
-        if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
-            cpu_to_le32(EXT4_OS_HURD)) {
+        if (likely(!test_opt2(inode->i_sb, HURD_COMPAT))) {
                 raw_inode->i_disk_version = cpu_to_le32(inode->i_version);
                 if (ei->i_extra_isize) {
                         if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi))