async_pq: Remove VLA usage

In the quest to remove VLAs from the kernel[1], this adjusts the
allocation of coefs and blocks to use the existing maximum values
(with one new define, MAX_DISKS for coefs, and a reuse of the
existing NDISKS for blocks).

[1] https://lkml.org/lkml/2018/3/7/621

Signed-off-by: Kyle Spiers <ksspiers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
Kyle Spiers 2018-06-01 13:20:16 -07:00 committed by Vinod Koul
parent ce397d215c
commit 89a7e2f752
2 changed files with 9 additions and 5 deletions

View File

@ -42,6 +42,8 @@ static struct page *pq_scribble_page;
#define P(b, d) (b[d-2])
#define Q(b, d) (b[d-1])
#define MAX_DISKS 255
/**
* do_async_gen_syndrome - asynchronously calculate P and/or Q
*/
@ -184,7 +186,7 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
struct dma_device *device = chan ? chan->device : NULL;
struct dmaengine_unmap_data *unmap = NULL;
BUG_ON(disks > 255 || !(P(blocks, disks) || Q(blocks, disks)));
BUG_ON(disks > MAX_DISKS || !(P(blocks, disks) || Q(blocks, disks)));
if (device)
unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOWAIT);
@ -196,7 +198,7 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
is_dma_pq_aligned(device, offset, 0, len)) {
struct dma_async_tx_descriptor *tx;
enum dma_ctrl_flags dma_flags = 0;
unsigned char coefs[src_cnt];
unsigned char coefs[MAX_DISKS];
int i, j;
/* run the p+q asynchronously */
@ -299,11 +301,11 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks,
struct dma_chan *chan = pq_val_chan(submit, blocks, disks, len);
struct dma_device *device = chan ? chan->device : NULL;
struct dma_async_tx_descriptor *tx;
unsigned char coefs[disks-2];
unsigned char coefs[MAX_DISKS];
enum dma_ctrl_flags dma_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0;
struct dmaengine_unmap_data *unmap = NULL;
BUG_ON(disks < 4);
BUG_ON(disks < 4 || disks > MAX_DISKS);
if (device)
unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOWAIT);

View File

@ -81,11 +81,13 @@ static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, stru
init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit);
} else {
struct page *blocks[disks];
struct page *blocks[NDISKS];
struct page *dest;
int count = 0;
int i;
BUG_ON(disks > NDISKS);
/* data+Q failure. Reconstruct data from P,
* then rebuild syndrome
*/