Hi,
2013-10-28 (월), 08:15 +0000, Shifei Ge:
> truncate_partial_nodes puts pages incorrectly in two cases.note that the
> value for argc 'depth' can only be 2 or 3(see truncate_inode_blocks
> --->truncate_partial_nodes ).
> first case:err happened in the first 'for' loop
> assume depth is 2,when err happened,pages[0] is invalid,so this page
> don't need to be put when func return,there is no problem.
> but when depth is 3 ,pages isn't put correctly when pages[0] is valid
> and pages[1] is invalid.in this case,depth is set to 2(ref to statemnt depth
> = i + 1) ,and then 'goto fail'.
> in label 'fail', for (i = depth - 3; i >= 0; i--) cann't meet the
> condition because i=-1,so pages[0] cann't be put when func return.
> second case:err happened in the second 'for' loop
> now,we've got pages[0] with argc 'depth' is 2 ,or we've got pages[0]
> and pages[1] with depth is 3.when err happend,we need 'goto fail' to put
> pages we've got.
> when depth is 2,in label 'fail',for (i = depth - 3; i >= 0; i--) cann't
> meet the condition because i=-1,so pages[0] cann't be put.
> when depth is 3,in label 'fail',for (i = depth - 3; i >= 0; i--) can
> only put pages[0],pages[1] also cann't be put.
> notes 'depth' has been changed before first 'goto fail'(ref to statemnt depth
> = i + 1),so pass this modified 'depth' to trace_f2fs_truncate_partial_nodes
> is also incorrectly.
Please write a description not to exceed 80 columns.
It's very hard to understand.
>
> From 9de8efa31759ce86a032f5ad092d337b686ede06 Mon Sep 17 00:00:00 2001
> Signed-off-by: Shifei Ge <shifei10...@samsung.com>
> ---
> fs/f2fs/node.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
> index 304d5ce..9986930 100644
> --- a/fs/f2fs/node.c
> +++ b/fs/f2fs/node.c
> @@ -625,6 +625,7 @@ static int truncate_partial_nodes(struct dnode_of_data
> *dn,
> int err = 0;
> int i;
> int idx = depth - 2;
> + int dep = depth;
I think we need to avoid using a local variable only for the use of
tracepoints below.
How about this?
---
fs/f2fs/node.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 304d5ce..8578719 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -631,11 +631,10 @@ static int truncate_partial_nodes(struct
dnode_of_data *dn,
return 0;
/* get indirect nodes in the path */
- for (i = 0; i < depth - 1; i++) {
+ for (i = 0; i < idx + 1; i++) {
/* refernece count'll be increased */
pages[i] = get_node_page(sbi, nid[i]);
if (IS_ERR(pages[i])) {
- depth = i + 1;
err = PTR_ERR(pages[i]);
goto fail;
}
@@ -643,7 +642,7 @@ static int truncate_partial_nodes(struct
dnode_of_data *dn,
}
/* free direct nodes linked to a partial indirect node */
- for (i = offset[depth - 1]; i < NIDS_PER_BLOCK; i++) {
+ for (i = offset[idx + 1]; i < NIDS_PER_BLOCK; i++) {
child_nid = get_nid(pages[idx], i, false);
if (!child_nid)
continue;
@@ -654,7 +653,7 @@ static int truncate_partial_nodes(struct
dnode_of_data *dn,
set_nid(pages[idx], i, 0, false);
}
- if (offset[depth - 1] == 0) {
+ if (offset[idx + 1] == 0) {
dn->node_page = pages[idx];
dn->nid = nid[idx];
truncate_node(dn);
@@ -662,9 +661,10 @@ static int truncate_partial_nodes(struct
dnode_of_data *dn,
f2fs_put_page(pages[idx], 1);
}
offset[idx]++;
- offset[depth - 1] = 0;
+ offset[idx + 1] = 0;
+ idx--;
fail:
- for (i = depth - 3; i >= 0; i--)
+ for (i = idx; i >= 0; i--)
f2fs_put_page(pages[i], 1);
trace_f2fs_truncate_partial_nodes(dn->inode, nid, depth, err);
--
1.8.4.474.g128a96c
--
Jaegeuk Kim
Samsung
------------------------------------------------------------------------------
October Webinars: Code for Performance
Free Intel webinars can help you accelerate application performance.
Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from
the latest Intel processors and coprocessors. See abstracts and register >
http://pubads.g.doubleclick.net/gampad/clk?id=60135991&iu=/4140/ostg.clktrk
_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
