UBIFS: allocate dump buffer on demand
Instead of using pre-allocated 'c->dbg->buf' buffer in
'dbg_dump_leb()', dynamically allocate it when needed. The intend
is to get rid of the pre-allocated 'c->dbg->buf' buffer and save
128KiB of RAM (or more if PEB size is larger). Indeed, currently we
allocate this memory even if the user never enables any self-check,
which is wasteful.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 02c10dc..c2e5c08 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -810,16 +810,24 @@
{
struct ubifs_scan_leb *sleb;
struct ubifs_scan_node *snod;
+ void *buf;
if (dbg_failure_mode)
return;
printk(KERN_DEBUG "(pid %d) start dumping LEB %d\n",
current->pid, lnum);
- sleb = ubifs_scan(c, lnum, 0, c->dbg->buf, 0);
+
+ buf = __vmalloc(c->leb_size, GFP_KERNEL | GFP_NOFS, PAGE_KERNEL);
+ if (!buf) {
+ ubifs_err("cannot allocate memory for dumping LEB %d", lnum);
+ return;
+ }
+
+ sleb = ubifs_scan(c, lnum, 0, buf, 0);
if (IS_ERR(sleb)) {
ubifs_err("scan error %d", (int)PTR_ERR(sleb));
- return;
+ goto out;
}
printk(KERN_DEBUG "LEB %d has %d nodes ending at %d\n", lnum,
@@ -835,6 +843,9 @@
printk(KERN_DEBUG "(pid %d) finish dumping LEB %d\n",
current->pid, lnum);
ubifs_scan_destroy(sleb);
+
+out:
+ vfree(buf);
return;
}