bcache: Stripe size isn't necessarily a power of two
Originally I got this right... except that the divides didn't use
do_div(), which broke 32 bit kernels. When I went to fix that, I forgot
that the raid stripe size usually isn't a power of two... doh
Signed-off-by: Kent Overstreet <[email protected]>
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 5786156..6e836f2 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -437,7 +437,7 @@
int flush_done;
uint64_t nr_stripes;
- unsigned stripe_size_bits;
+ unsigned stripe_size;
atomic_t *stripe_sectors_dirty;
unsigned long sectors_dirty_last;
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 74f2e90..d3169c0 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -761,11 +761,10 @@
struct request_queue *q;
size_t n;
- if (!d->stripe_size_bits)
- d->stripe_size_bits = 31;
+ if (!d->stripe_size)
+ d->stripe_size = 1 << 31;
- d->nr_stripes = round_up(sectors, 1 << d->stripe_size_bits) >>
- d->stripe_size_bits;
+ d->nr_stripes = DIV_ROUND_UP_ULL(sectors, d->stripe_size);
if (!d->nr_stripes || d->nr_stripes > SIZE_MAX / sizeof(atomic_t))
return -ENOMEM;
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index 4211d82..b3a66f1 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -157,7 +157,7 @@
sysfs_hprint(dirty_data,
bcache_dev_sectors_dirty(&dc->disk) << 9);
- sysfs_hprint(stripe_size, (1 << dc->disk.stripe_size_bits) << 9);
+ sysfs_hprint(stripe_size, dc->disk.stripe_size << 9);
var_printf(partial_stripes_expensive, "%u");
var_printf(sequential_merge, "%i");
diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index ba3ee48..b842fbf 100644
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -114,25 +114,25 @@
static bool dirty_full_stripe_pred(struct keybuf *buf, struct bkey *k)
{
- uint64_t stripe;
+ uint64_t stripe = KEY_START(k);
unsigned nr_sectors = KEY_SIZE(k);
struct cached_dev *dc = container_of(buf, struct cached_dev,
writeback_keys);
- unsigned stripe_size = 1 << dc->disk.stripe_size_bits;
if (!KEY_DIRTY(k))
return false;
- stripe = KEY_START(k) >> dc->disk.stripe_size_bits;
- while (1) {
- if (atomic_read(dc->disk.stripe_sectors_dirty + stripe) !=
- stripe_size)
- return false;
+ do_div(stripe, dc->disk.stripe_size);
- if (nr_sectors <= stripe_size)
+ while (1) {
+ if (atomic_read(dc->disk.stripe_sectors_dirty + stripe) ==
+ dc->disk.stripe_size)
return true;
- nr_sectors -= stripe_size;
+ if (nr_sectors <= dc->disk.stripe_size)
+ return false;
+
+ nr_sectors -= dc->disk.stripe_size;
stripe++;
}
}
@@ -186,11 +186,12 @@
for (i = 0; i < dc->disk.nr_stripes; i++)
if (atomic_read(dc->disk.stripe_sectors_dirty + i) ==
- 1 << dc->disk.stripe_size_bits)
+ dc->disk.stripe_size)
goto full_stripes;
goto normal_refill;
full_stripes:
+ searched_from_start = false; /* not searching entire btree */
bch_refill_keybuf(dc->disk.c, buf, &end,
dirty_full_stripe_pred);
} else {
@@ -252,19 +253,19 @@
uint64_t offset, int nr_sectors)
{
struct bcache_device *d = c->devices[inode];
- unsigned stripe_size, stripe_offset;
- uint64_t stripe;
+ unsigned stripe_offset;
+ uint64_t stripe = offset;
if (!d)
return;
- stripe_size = 1 << d->stripe_size_bits;
- stripe = offset >> d->stripe_size_bits;
- stripe_offset = offset & (stripe_size - 1);
+ do_div(stripe, d->stripe_size);
+
+ stripe_offset = offset & (d->stripe_size - 1);
while (nr_sectors) {
int s = min_t(unsigned, abs(nr_sectors),
- stripe_size - stripe_offset);
+ d->stripe_size - stripe_offset);
if (nr_sectors < 0)
s = -s;
diff --git a/drivers/md/bcache/writeback.h b/drivers/md/bcache/writeback.h
index c91f61b..3496188 100644
--- a/drivers/md/bcache/writeback.h
+++ b/drivers/md/bcache/writeback.h
@@ -18,16 +18,18 @@
uint64_t offset,
unsigned nr_sectors)
{
- uint64_t stripe = offset >> d->stripe_size_bits;
+ uint64_t stripe = offset;
+
+ do_div(stripe, d->stripe_size);
while (1) {
if (atomic_read(d->stripe_sectors_dirty + stripe))
return true;
- if (nr_sectors <= 1 << d->stripe_size_bits)
+ if (nr_sectors <= d->stripe_size)
return false;
- nr_sectors -= 1 << d->stripe_size_bits;
+ nr_sectors -= d->stripe_size;
stripe++;
}
}
