ext4: Use bitops to read/modify i_flags in struct ext4_inode_info

At several places we modify EXT4_I(inode)->i_flags without holding
i_mutex (ext4_do_update_inode, ...). These modifications are racy and
we can lose updates to i_flags. So convert handling of i_flags to use
bitops which are atomic.

https://bugzilla.kernel.org/show_bug.cgi?id=15792

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 15 insertions, 15 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 3b687725758..c2b0724e8ad 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -931,7 +931,7 @@ static int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
         int count = 0;
         ext4_fsblk_t first_block = 0;
 
-        J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL));
+        J_ASSERT(!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)));
         J_ASSERT(handle != NULL || (flags & EXT4_GET_BLOCKS_CREATE) == 0);
         depth = ext4_block_to_path(inode, map->m_lblk, offsets,
                                    &blocks_to_boundary);
@@ -1059,7 +1059,7 @@ static int ext4_indirect_calc_metadata_amount(struct inode *inode,
  */
 static int ext4_calc_metadata_amount(struct inode *inode, sector_t lblock)
 {
-        if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
+        if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
                 return ext4_ext_calc_metadata_amount(inode, lblock);
 
         return ext4_indirect_calc_metadata_amount(inode, lblock);
@@ -1236,7 +1236,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
          * file system block.
          */
         down_read((&EXT4_I(inode)->i_data_sem));
-        if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) {
+        if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
                 retval = ext4_ext_map_blocks(handle, inode, map, 0);
         } else {
                 retval = ext4_ind_map_blocks(handle, inode, map, 0);
@@ -1295,7 +1295,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
          * We need to check for EXT4 here because migrate
          * could have changed the inode type in between
          */
-        if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) {
+        if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
                 retval = ext4_ext_map_blocks(handle, inode, map, flags);
         } else {
                 retval = ext4_ind_map_blocks(handle, inode, map, flags);
@@ -2325,7 +2325,7 @@ static void mpage_add_bh_to_extent(struct mpage_da_data *mpd,
                 goto flush_it;
 
         /* check if thereserved journal credits might overflow */
-        if (!(EXT4_I(mpd->inode)->i_flags & EXT4_EXTENTS_FL)) {
+        if (!(ext4_test_inode_flag(mpd->inode, EXT4_INODE_EXTENTS))) {
                 if (nrblocks >= EXT4_MAX_TRANS_DATA) {
                         /*
                          * With non-extent format we are limited by the journal
@@ -2779,7 +2779,7 @@ static int ext4_da_writepages_trans_blocks(struct inode *inode)
          * number of contiguous block. So we will limit
          * number of contiguous block to a sane value
          */
-        if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) &&
+        if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) &&
             (max_blocks > EXT4_MAX_TRANS_DATA))
                 max_blocks = EXT4_MAX_TRANS_DATA;
 
@@ -3995,7 +3995,7 @@ static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
         struct file *file = iocb->ki_filp;
         struct inode *inode = file->f_mapping->host;
 
-        if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
+        if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
                 return ext4_ext_direct_IO(rw, iocb, iov, offset, nr_segs);
 
         return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs);
@@ -4631,12 +4631,12 @@ void ext4_truncate(struct inode *inode)
         if (!ext4_can_truncate(inode))
                 return;
 
-        EXT4_I(inode)->i_flags &= ~EXT4_EOFBLOCKS_FL;
+        ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
 
         if (inode->i_size == 0 && !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC))
                 ext4_set_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE);
 
-        if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) {
+        if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
                 ext4_ext_truncate(inode);
                 return;
         }
@@ -5473,7 +5473,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
         }
 
         if (attr->ia_valid & ATTR_SIZE) {
-                if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) {
+                if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
                         struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 
                         if (attr->ia_size > sbi->s_bitmap_maxbytes) {
@@ -5486,7 +5486,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
         if (S_ISREG(inode->i_mode) &&
             attr->ia_valid & ATTR_SIZE &&
             (attr->ia_size < inode->i_size ||
-             (EXT4_I(inode)->i_flags & EXT4_EOFBLOCKS_FL))) {
+             (ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS)))) {
                 handle_t *handle;
 
                 handle = ext4_journal_start(inode, 3);
@@ -5518,7 +5518,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
                         }
                 }
                 /* ext4_truncate will clear the flag */
-                if ((EXT4_I(inode)->i_flags & EXT4_EOFBLOCKS_FL))
+                if ((ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS)))
                         ext4_truncate(inode);
         }
 
@@ -5594,7 +5594,7 @@ static int ext4_indirect_trans_blocks(struct inode *inode, int nrblocks,
 
 static int ext4_index_trans_blocks(struct inode *inode, int nrblocks, int chunk)
 {
-        if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
+        if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
                 return ext4_indirect_trans_blocks(inode, nrblocks, chunk);
         return ext4_ext_index_trans_blocks(inode, nrblocks, chunk);
 }
@@ -5929,9 +5929,9 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val)
          */
 
         if (val)
-                EXT4_I(inode)->i_flags |= EXT4_JOURNAL_DATA_FL;
+                ext4_set_inode_flag(inode, EXT4_INODE_JOURNAL_DATA);
         else
-                EXT4_I(inode)->i_flags &= ~EXT4_JOURNAL_DATA_FL;
+                ext4_clear_inode_flag(inode, EXT4_INODE_JOURNAL_DATA);
         ext4_set_aops(inode);
 
         jbd2_journal_unlock_updates(journal);