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Diffstat (limited to 'fs/ext4/indirect.c')
-rw-r--r--fs/ext4/indirect.c125
1 files changed, 77 insertions, 48 deletions
diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c
index 36699a131168..3a4ab70fe9e0 100644
--- a/fs/ext4/indirect.c
+++ b/fs/ext4/indirect.c
@@ -331,11 +331,14 @@ static int ext4_alloc_branch(handle_t *handle,
for (i = 0; i <= indirect_blks; i++) {
if (i == indirect_blks) {
new_blocks[i] = ext4_mb_new_blocks(handle, ar, &err);
- } else
+ } else {
ar->goal = new_blocks[i] = ext4_new_meta_blocks(handle,
ar->inode, ar->goal,
ar->flags & EXT4_MB_DELALLOC_RESERVED,
NULL, &err);
+ /* Simplify error cleanup... */
+ branch[i+1].bh = NULL;
+ }
if (err) {
i--;
goto failed;
@@ -377,18 +380,25 @@ static int ext4_alloc_branch(handle_t *handle,
}
return 0;
failed:
+ if (i == indirect_blks) {
+ /* Free data blocks */
+ ext4_free_blocks(handle, ar->inode, NULL, new_blocks[i],
+ ar->len, 0);
+ i--;
+ }
for (; i >= 0; i--) {
/*
* We want to ext4_forget() only freshly allocated indirect
- * blocks. Buffer for new_blocks[i-1] is at branch[i].bh and
- * buffer at branch[0].bh is indirect block / inode already
- * existing before ext4_alloc_branch() was called.
+ * blocks. Buffer for new_blocks[i] is at branch[i+1].bh
+ * (buffer at branch[0].bh is indirect block / inode already
+ * existing before ext4_alloc_branch() was called). Also
+ * because blocks are freshly allocated, we don't need to
+ * revoke them which is why we don't set
+ * EXT4_FREE_BLOCKS_METADATA.
*/
- if (i > 0 && i != indirect_blks && branch[i].bh)
- ext4_forget(handle, 1, ar->inode, branch[i].bh,
- branch[i].bh->b_blocknr);
- ext4_free_blocks(handle, ar->inode, NULL, new_blocks[i],
- (i == indirect_blks) ? ar->len : 1, 0);
+ ext4_free_blocks(handle, ar->inode, branch[i+1].bh,
+ new_blocks[i], 1,
+ branch[i+1].bh ? EXT4_FREE_BLOCKS_FORGET : 0);
}
return err;
}
@@ -689,27 +699,63 @@ int ext4_ind_trans_blocks(struct inode *inode, int nrblocks)
return DIV_ROUND_UP(nrblocks, EXT4_ADDR_PER_BLOCK(inode->i_sb)) + 4;
}
+static int ext4_ind_trunc_restart_fn(handle_t *handle, struct inode *inode,
+ struct buffer_head *bh, int *dropped)
+{
+ int err;
+
+ if (bh) {
+ BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
+ err = ext4_handle_dirty_metadata(handle, inode, bh);
+ if (unlikely(err))
+ return err;
+ }
+ err = ext4_mark_inode_dirty(handle, inode);
+ if (unlikely(err))
+ return err;
+ /*
+ * Drop i_data_sem to avoid deadlock with ext4_map_blocks. At this
+ * moment, get_block can be called only for blocks inside i_size since
+ * page cache has been already dropped and writes are blocked by
+ * i_mutex. So we can safely drop the i_data_sem here.
+ */
+ BUG_ON(EXT4_JOURNAL(inode) == NULL);
+ ext4_discard_preallocations(inode);
+ up_write(&EXT4_I(inode)->i_data_sem);
+ *dropped = 1;
+ return 0;
+}
+
/*
* Truncate transactions can be complex and absolutely huge. So we need to
* be able to restart the transaction at a conventient checkpoint to make
* sure we don't overflow the journal.
*
* 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
- *
- * 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.
+ * extend fails, we restart transaction.
*/
-static int try_to_extend_transaction(handle_t *handle, struct inode *inode)
+static int ext4_ind_truncate_ensure_credits(handle_t *handle,
+ struct inode *inode,
+ struct buffer_head *bh,
+ int revoke_creds)
{
- if (!ext4_handle_valid(handle))
- return 0;
- if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1))
- return 0;
- if (!ext4_journal_extend(handle, ext4_blocks_for_truncate(inode)))
- return 0;
- return 1;
+ int ret;
+ int dropped = 0;
+
+ ret = ext4_journal_ensure_credits_fn(handle, EXT4_RESERVE_TRANS_BLOCKS,
+ ext4_blocks_for_truncate(inode), revoke_creds,
+ ext4_ind_trunc_restart_fn(handle, inode, bh, &dropped));
+ if (dropped)
+ down_write(&EXT4_I(inode)->i_data_sem);
+ if (ret <= 0)
+ return ret;
+ if (bh) {
+ BUFFER_TRACE(bh, "retaking write access");
+ ret = ext4_journal_get_write_access(handle, bh);
+ if (unlikely(ret))
+ return ret;
+ }
+ return 0;
}
/*
@@ -844,27 +890,10 @@ static int ext4_clear_blocks(handle_t *handle, struct inode *inode,
return 1;
}
- if (try_to_extend_transaction(handle, inode)) {
- if (bh) {
- BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
- err = ext4_handle_dirty_metadata(handle, inode, bh);
- if (unlikely(err))
- goto out_err;
- }
- err = ext4_mark_inode_dirty(handle, inode);
- if (unlikely(err))
- goto out_err;
- err = ext4_truncate_restart_trans(handle, inode,
- ext4_blocks_for_truncate(inode));
- if (unlikely(err))
- goto out_err;
- if (bh) {
- BUFFER_TRACE(bh, "retaking write access");
- err = ext4_journal_get_write_access(handle, bh);
- if (unlikely(err))
- goto out_err;
- }
- }
+ err = ext4_ind_truncate_ensure_credits(handle, inode, bh,
+ ext4_free_data_revoke_credits(inode, count));
+ if (err < 0)
+ goto out_err;
for (p = first; p < last; p++)
*p = 0;
@@ -1047,11 +1076,11 @@ static void ext4_free_branches(handle_t *handle, struct inode *inode,
*/
if (ext4_handle_is_aborted(handle))
return;
- if (try_to_extend_transaction(handle, inode)) {
- ext4_mark_inode_dirty(handle, inode);
- ext4_truncate_restart_trans(handle, inode,
- ext4_blocks_for_truncate(inode));
- }
+ if (ext4_ind_truncate_ensure_credits(handle, inode,
+ NULL,
+ ext4_free_metadata_revoke_credits(
+ inode->i_sb, 1)) < 0)
+ return;
/*
* The forget flag here is critical because if