UBIFS: allocate scanning buffer on demand
Instead of using pre-allocated 'c->dbg->buf' buffer in
'scan_check_cb()', 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/lprops.c b/fs/ubifs/lprops.c
index 4d4ca38..c7b25e2 100644
--- a/fs/ubifs/lprops.c
+++ b/fs/ubifs/lprops.c
@@ -1035,7 +1035,8 @@
struct ubifs_scan_leb *sleb;
struct ubifs_scan_node *snod;
struct ubifs_lp_stats *lst = &data->lst;
- int cat, lnum = lp->lnum, is_idx = 0, used = 0, free, dirty;
+ int cat, lnum = lp->lnum, is_idx = 0, used = 0, free, dirty, ret;
+ void *buf = NULL;
cat = lp->flags & LPROPS_CAT_MASK;
if (cat != LPROPS_UNCAT) {
@@ -1093,7 +1094,13 @@
}
}
- 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 to scan LEB %d", lnum);
+ goto out;
+ }
+
+ sleb = ubifs_scan(c, lnum, 0, buf, 0);
if (IS_ERR(sleb)) {
/*
* After an unclean unmount, empty and freeable LEBs
@@ -1105,7 +1112,8 @@
lst->empty_lebs += 1;
lst->total_free += c->leb_size;
lst->total_dark += ubifs_calc_dark(c, c->leb_size);
- return LPT_SCAN_CONTINUE;
+ ret = LPT_SCAN_CONTINUE;
+ goto exit;
}
if (lp->free + lp->dirty == c->leb_size &&
@@ -1115,10 +1123,12 @@
lst->total_free += lp->free;
lst->total_dirty += lp->dirty;
lst->total_dark += ubifs_calc_dark(c, c->leb_size);
- return LPT_SCAN_CONTINUE;
+ ret = LPT_SCAN_CONTINUE;
+ goto exit;
}
data->err = PTR_ERR(sleb);
- return LPT_SCAN_STOP;
+ ret = LPT_SCAN_STOP;
+ goto exit;
}
is_idx = -1;
@@ -1236,7 +1246,10 @@
}
ubifs_scan_destroy(sleb);
- return LPT_SCAN_CONTINUE;
+ ret = LPT_SCAN_CONTINUE;
+exit:
+ vfree(buf);
+ return ret;
out_print:
ubifs_err("bad accounting of LEB %d: free %d, dirty %d flags %#x, "
@@ -1246,6 +1259,7 @@
out_destroy:
ubifs_scan_destroy(sleb);
out:
+ vfree(buf);
data->err = -EINVAL;
return LPT_SCAN_STOP;
}