ext4: refactor truncate code
Move common code in ext4_ind_truncate() and ext4_ext_truncate() into
ext4_truncate(). This saves over 60 lines of code.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c
index d884677..98be6f6 100644
--- a/fs/ext4/indirect.c
+++ b/fs/ext4/indirect.c
@@ -806,26 +806,9 @@
* be able to restart the transaction at a conventient checkpoint to make
* sure we don't overflow the journal.
*
- * start_transaction gets us a new handle for a truncate transaction,
- * and extend_transaction tries to extend the existing one a bit. If
+ * Try to extend this transaction for the purposes of truncation. If
* extend fails, we need to propagate the failure up and restart the
* transaction in the top-level truncate loop. --sct
- */
-static handle_t *start_transaction(struct inode *inode)
-{
- handle_t *result;
-
- result = ext4_journal_start(inode, EXT4_HT_TRUNCATE,
- ext4_blocks_for_truncate(inode));
- if (!IS_ERR(result))
- return result;
-
- ext4_std_error(inode->i_sb, PTR_ERR(result));
- return result;
-}
-
-/*
- * Try to extend this transaction for the purposes of truncation.
*
* Returns 0 if we managed to create more room. If we can't create more
* room, and the transaction must be restarted we return 1.
@@ -1218,68 +1201,30 @@
}
}
-void ext4_ind_truncate(struct inode *inode)
+void ext4_ind_truncate(handle_t *handle, struct inode *inode)
{
- handle_t *handle;
struct ext4_inode_info *ei = EXT4_I(inode);
__le32 *i_data = ei->i_data;
int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb);
- struct address_space *mapping = inode->i_mapping;
ext4_lblk_t offsets[4];
Indirect chain[4];
Indirect *partial;
__le32 nr = 0;
int n = 0;
ext4_lblk_t last_block, max_block;
- loff_t page_len;
unsigned blocksize = inode->i_sb->s_blocksize;
- int err;
-
- handle = start_transaction(inode);
- if (IS_ERR(handle))
- return; /* AKPM: return what? */
last_block = (inode->i_size + blocksize-1)
>> EXT4_BLOCK_SIZE_BITS(inode->i_sb);
max_block = (EXT4_SB(inode->i_sb)->s_bitmap_maxbytes + blocksize-1)
>> EXT4_BLOCK_SIZE_BITS(inode->i_sb);
- if (inode->i_size % PAGE_CACHE_SIZE != 0) {
- page_len = PAGE_CACHE_SIZE -
- (inode->i_size & (PAGE_CACHE_SIZE - 1));
-
- err = ext4_discard_partial_page_buffers(handle,
- mapping, inode->i_size, page_len, 0);
-
- if (err)
- goto out_stop;
- }
-
if (last_block != max_block) {
n = ext4_block_to_path(inode, last_block, offsets, NULL);
if (n == 0)
- goto out_stop; /* error */
+ return;
}
- /*
- * OK. This truncate is going to happen. We add the inode to the
- * orphan list, so that if this truncate spans multiple transactions,
- * and we crash, we will resume the truncate when the filesystem
- * recovers. It also marks the inode dirty, to catch the new size.
- *
- * Implication: the file must always be in a sane, consistent
- * truncatable state while each transaction commits.
- */
- if (ext4_orphan_add(handle, inode))
- goto out_stop;
-
- /*
- * From here we block out all ext4_get_block() callers who want to
- * modify the block allocation tree.
- */
- down_write(&ei->i_data_sem);
-
- ext4_discard_preallocations(inode);
ext4_es_remove_extent(inode, last_block, EXT_MAX_BLOCKS - last_block);
/*
@@ -1296,7 +1241,7 @@
* It is unnecessary to free any data blocks if last_block is
* equal to the indirect block limit.
*/
- goto out_unlock;
+ return;
} else if (n == 1) { /* direct blocks */
ext4_free_data(handle, inode, NULL, i_data+offsets[0],
i_data + EXT4_NDIR_BLOCKS);
@@ -1356,31 +1301,6 @@
case EXT4_TIND_BLOCK:
;
}
-
-out_unlock:
- up_write(&ei->i_data_sem);
- inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
- ext4_mark_inode_dirty(handle, inode);
-
- /*
- * In a multi-transaction truncate, we only make the final transaction
- * synchronous
- */
- if (IS_SYNC(inode))
- ext4_handle_sync(handle);
-out_stop:
- /*
- * If this was a simple ftruncate(), and the file will remain alive
- * then we need to clear up the orphan record which we created above.
- * However, if this was a real unlink then we were called by
- * ext4_delete_inode(), and we allow that function to clean up the
- * orphan info for us.
- */
- if (inode->i_nlink)
- ext4_orphan_del(handle, inode);
-
- ext4_journal_stop(handle);
- trace_ext4_truncate_exit(inode);
}
static int free_hole_blocks(handle_t *handle, struct inode *inode,