summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMikulas Patocka <mpatocka@redhat.com>2020-06-02 15:34:40 +0200
committerMike Snitzer <snitzer@redhat.com>2020-06-05 14:59:41 -0400
commit33a180623b6c35f2727daecb63763955af3af1df (patch)
treedf17dbb862aee516cf07560d58b2175c95339306
parent88f878e58879acfdad03e08776c9802f9cd6f26a (diff)
dm bufio: introduce forget_buffer_locked
Introduce a function forget_buffer_locked that forgets a range of buffers. It is more efficient than calling forget_buffer in a loop. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
-rw-r--r--drivers/md/dm-bufio.c60
-rw-r--r--include/linux/dm-bufio.h7
2 files changed, 63 insertions, 4 deletions
diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
index ff19add97e0b..95f6c544aa01 100644
--- a/drivers/md/dm-bufio.c
+++ b/drivers/md/dm-bufio.c
@@ -262,6 +262,29 @@ static struct dm_buffer *__find(struct dm_bufio_client *c, sector_t block)
return NULL;
}
+static struct dm_buffer *__find_next(struct dm_bufio_client *c, sector_t block)
+{
+ struct rb_node *n = c->buffer_tree.rb_node;
+ struct dm_buffer *b;
+ struct dm_buffer *best = NULL;
+
+ while (n) {
+ b = container_of(n, struct dm_buffer, node);
+
+ if (b->block == block)
+ return b;
+
+ if (block <= b->block) {
+ n = n->rb_left;
+ best = b;
+ } else {
+ n = n->rb_right;
+ }
+ }
+
+ return best;
+}
+
static void __insert(struct dm_bufio_client *c, struct dm_buffer *b)
{
struct rb_node **new = &c->buffer_tree.rb_node, *parent = NULL;
@@ -1434,6 +1457,14 @@ retry:
}
EXPORT_SYMBOL_GPL(dm_bufio_release_move);
+static void forget_buffer_locked(struct dm_buffer *b)
+{
+ if (likely(!b->hold_count) && likely(!b->state)) {
+ __unlink_buffer(b);
+ __free_buffer_wake(b);
+ }
+}
+
/*
* Free the given buffer.
*
@@ -1447,15 +1478,36 @@ void dm_bufio_forget(struct dm_bufio_client *c, sector_t block)
dm_bufio_lock(c);
b = __find(c, block);
- if (b && likely(!b->hold_count) && likely(!b->state)) {
- __unlink_buffer(b);
- __free_buffer_wake(b);
- }
+ if (b)
+ forget_buffer_locked(b);
dm_bufio_unlock(c);
}
EXPORT_SYMBOL_GPL(dm_bufio_forget);
+void dm_bufio_forget_buffers(struct dm_bufio_client *c, sector_t block, sector_t n_blocks)
+{
+ struct dm_buffer *b;
+ sector_t end_block = block + n_blocks;
+
+ while (block < end_block) {
+ dm_bufio_lock(c);
+
+ b = __find_next(c, block);
+ if (b) {
+ block = b->block + 1;
+ forget_buffer_locked(b);
+ }
+
+ dm_bufio_unlock(c);
+
+ if (!b)
+ break;
+ }
+
+}
+EXPORT_SYMBOL_GPL(dm_bufio_forget_buffers);
+
void dm_bufio_set_minimum_buffers(struct dm_bufio_client *c, unsigned n)
{
c->minimum_buffers = n;
diff --git a/include/linux/dm-bufio.h b/include/linux/dm-bufio.h
index 5ec6bfbde9ae..29d255fdd5d6 100644
--- a/include/linux/dm-bufio.h
+++ b/include/linux/dm-bufio.h
@@ -137,6 +137,13 @@ void dm_bufio_release_move(struct dm_buffer *b, sector_t new_block);
void dm_bufio_forget(struct dm_bufio_client *c, sector_t block);
/*
+ * Free the given range of buffers.
+ * This is just a hint, if the buffer is in use or dirty, this function
+ * does nothing.
+ */
+void dm_bufio_forget_buffers(struct dm_bufio_client *c, sector_t block, sector_t n_blocks);
+
+/*
* Set the minimum number of buffers before cleanup happens.
*/
void dm_bufio_set_minimum_buffers(struct dm_bufio_client *c, unsigned n);