drbd: get rid of unused debug code
Long time ago, we had paranoia code in the bitmap that allocated one
extra word, assigned a magic value, and checked on every occasion that
the magic value was still unchanged.
That debug code is unused, the extra long word complicates code a bit.
Get rid of it.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c
index 0e31e57..09d208b 100644
--- a/drivers/block/drbd/drbd_bitmap.c
+++ b/drivers/block/drbd/drbd_bitmap.c
@@ -488,10 +488,7 @@
* on disk and in core memory alike */
mask = cpu_to_lel(mask);
- /* because of the "extra long to catch oob access" we allocate in
- * drbd_bm_resize, bm_number_of_pages -1 is not necessarily the page
- * containing the last _relevant_ bitmap word */
- p_addr = bm_map_pidx(b, bm_bit_to_page_idx(b, b->bm_bits - 1));
+ p_addr = bm_map_pidx(b, b->bm_number_of_pages - 1);
bm = p_addr + (tmp/BITS_PER_LONG);
if (mask) {
/* If mask != 0, we are not exactly aligned, so bm now points
@@ -527,10 +524,7 @@
* on disk and in core memory alike */
mask = cpu_to_lel(mask);
- /* because of the "extra long to catch oob access" we allocate in
- * drbd_bm_resize, bm_number_of_pages -1 is not necessarily the page
- * containing the last _relevant_ bitmap word */
- p_addr = bm_map_pidx(b, bm_bit_to_page_idx(b, b->bm_bits - 1));
+ p_addr = bm_map_pidx(b, b->bm_number_of_pages - 1);
bm = p_addr + (tmp/BITS_PER_LONG);
if (mask) {
/* If mask != 0, we are not exactly aligned, so bm now points
@@ -556,15 +550,10 @@
unsigned long *p_addr;
unsigned long bits = 0;
unsigned long mask = (1UL << (b->bm_bits & BITS_PER_LONG_MASK)) -1;
- int idx, last_page, i, last_word;
-
- /* because of the "extra long to catch oob access" we allocate in
- * drbd_bm_resize, bm_number_of_pages -1 is not necessarily the page
- * containing the last _relevant_ bitmap word */
- last_page = bm_bit_to_page_idx(b, b->bm_bits-1);
+ int idx, i, last_word;
/* all but last page */
- for (idx = 0; idx < last_page; idx++) {
+ for (idx = 0; idx < b->bm_number_of_pages - 1; idx++) {
p_addr = __bm_map_pidx(b, idx, KM_USER0);
for (i = 0; i < LWPP; i++)
bits += hweight_long(p_addr[i]);
@@ -627,7 +616,7 @@
int drbd_bm_resize(struct drbd_conf *mdev, sector_t capacity, int set_new_bits)
{
struct drbd_bitmap *b = mdev->bitmap;
- unsigned long bits, words, owords, obits, *p_addr, *bm;
+ unsigned long bits, words, owords, obits;
unsigned long want, have, onpages; /* number of pages */
struct page **npages, **opages = NULL;
int err = 0, growing;
@@ -681,8 +670,7 @@
}
}
- /* one extra long to catch off by one errors */
- want = ALIGN((words+1)*sizeof(long), PAGE_SIZE) >> PAGE_SHIFT;
+ want = ALIGN(words*sizeof(long), PAGE_SIZE) >> PAGE_SHIFT;
have = b->bm_number_of_pages;
if (want == have) {
D_ASSERT(b->bm_pages != NULL);
@@ -728,11 +716,6 @@
bm_free_pages(opages + want, have - want);
}
- p_addr = bm_map_pidx(b, bm_word_to_page_idx(b, words));
- bm = p_addr + MLPP(words);
- *bm = DRBD_MAGIC;
- bm_unmap(p_addr);
-
(void)bm_clear_surplus(b);
spin_unlock_irq(&b->bm_lock);
@@ -845,7 +828,6 @@
*/
if (end == b->bm_words)
b->bm_set -= bm_clear_surplus(b);
-
spin_unlock_irq(&b->bm_lock);
}
@@ -1030,7 +1012,7 @@
struct bm_aio_ctx ctx =
{ .flags = lazy_writeout_upper_idx ? BM_AIO_COPY_PAGES : 0 };
struct drbd_bitmap *b = mdev->bitmap;
- int last_page, i, count = 0;
+ int num_pages, i, count = 0;
unsigned long now;
char ppb[10];
int err = 0;
@@ -1046,10 +1028,7 @@
if (!ctx.flags)
WARN_ON(!bm_is_locked(b));
- /* because of the "extra long to catch oob access" we allocate in
- * drbd_bm_resize, bm_number_of_pages -1 is not necessarily the page
- * containing the last _relevant_ bitmap word */
- last_page = bm_word_to_page_idx(b, b->bm_words - 1);
+ num_pages = b->bm_number_of_pages;
now = jiffies;
ctx.mdev = mdev;
@@ -1058,7 +1037,7 @@
ctx.error = 0;
/* let the layers below us try to merge these bios... */
- for (i = 0; i <= last_page; i++) {
+ for (i = 0; i < num_pages; i++) {
/* ignore completely unchanged pages */
if (lazy_writeout_upper_idx && i == lazy_writeout_upper_idx)
break;