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>
This commit is contained in:
Artem Bityutskiy 2011-03-11 15:50:37 +02:00
parent 73d9aec3fd
commit cd5f7485bb

View File

@ -1035,7 +1035,8 @@ static int scan_check_cb(struct ubifs_info *c,
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 @@ static int scan_check_cb(struct ubifs_info *c,
}
}
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 @@ static int scan_check_cb(struct ubifs_info *c,
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 @@ static int scan_check_cb(struct ubifs_info *c,
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 @@ static int scan_check_cb(struct ubifs_info *c,
}
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 @@ static int scan_check_cb(struct ubifs_info *c,
out_destroy:
ubifs_scan_destroy(sleb);
out:
vfree(buf);
data->err = -EINVAL;
return LPT_SCAN_STOP;
}