[PATCH v4 10/15] md/raid5: add offset array in scribble buffer
From: Yufen Yu <hidden>
Date: 2020-06-12 11:42:15
Subsystem:
software raid (multiple disks) support, the rest · Maintainers:
Song Liu, Yu Kuai, Linus Torvalds
When enable shared buffers for stripe_head, it need an offset array to record page offset to compute xor. To avoid repeatly allocate an new array each time, we add a memory region into scribble buffer to record offset. Signed-off-by: Yufen Yu <redacted> --- drivers/md/raid5.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index f8c945645272..053f914424f7 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c@@ -1477,6 +1477,15 @@ static addr_conv_t *to_addr_conv(struct stripe_head *sh, return (void *) (to_addr_page(percpu, i) + sh->disks + 2); } +/* + * Return a pointer to record offset address. + */ +static unsigned int * +to_addr_offs(struct stripe_head *sh, struct raid5_percpu *percpu) +{ + return (unsigned int *) (to_addr_conv(sh, percpu, 0) + sh->disks + 2); +} + static struct dma_async_tx_descriptor * ops_run_compute5(struct stripe_head *sh, struct raid5_percpu *percpu) {
@@ -2357,8 +2366,9 @@ static int scribble_alloc(struct raid5_percpu *percpu, int num, int cnt, gfp_t flags) { size_t obj_size = - sizeof(struct page *) * (num+2) + - sizeof(addr_conv_t) * (num+2); + sizeof(struct page *) * (num + 2) + + sizeof(addr_conv_t) * (num + 2) + + sizeof(unsigned int) * (num + 2); void *scribble; scribble = kvmalloc_array(cnt, obj_size, flags);
--
2.21.3