In the quest to remove VLAs from the kernel[1], this moves the allocation of coefs and blocks from the stack to being kmalloc()ed. [1] https://lkml.org/lkml/2018/3/7/621 Signed-off-by: Kyle Spiers <ksspiers@xxxxxxxxxx> --- Forgot to add slab.h --- crypto/async_tx/async_pq.c | 18 ++++++++++++++---- crypto/async_tx/raid6test.c | 9 ++++++++- 2 files changed, 22 insertions(+), 5 deletions(-) diff --git a/crypto/async_tx/async_pq.c b/crypto/async_tx/async_pq.c index 56bd612927ab..af1912313a23 100644 --- a/crypto/async_tx/async_pq.c +++ b/crypto/async_tx/async_pq.c @@ -194,9 +194,9 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks, (src_cnt <= dma_maxpq(device, 0) || dma_maxpq(device, DMA_PREP_CONTINUE) > 0) && is_dma_pq_aligned(device, offset, 0, len)) { - struct dma_async_tx_descriptor *tx; + struct dma_async_tx_descriptor *tx = NULL; enum dma_ctrl_flags dma_flags = 0; - unsigned char coefs[src_cnt]; + unsigned char *coefs; int i, j; /* run the p+q asynchronously */ @@ -207,6 +207,9 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks, * sources and update the coefficients accordingly */ unmap->len = len; + coefs = kmalloc_array(src_cnt, sizeof(*coefs), GFP_KERNEL); + if (!coefs) + goto out; for (i = 0, j = 0; i < src_cnt; i++) { if (blocks[i] == NULL) continue; @@ -240,7 +243,9 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks, } tx = do_async_gen_syndrome(chan, coefs, j, unmap, dma_flags, submit); +out: dmaengine_unmap_put(unmap); + kfree(coefs); return tx; } @@ -298,8 +303,8 @@ 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]; + struct dma_async_tx_descriptor *tx = NULL; + unsigned char *coefs = NULL; enum dma_ctrl_flags dma_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0; struct dmaengine_unmap_data *unmap = NULL; @@ -318,6 +323,9 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks, __func__, disks, len); unmap->len = len; + coefs = kmalloc_array(disks - 2, sizeof(*coefs), GFP_KERNEL); + if (!coefs) + goto out; for (i = 0; i < disks-2; i++) if (likely(blocks[i])) { unmap->addr[j] = dma_map_page(dev, blocks[i], @@ -423,6 +431,8 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks, async_tx_sync_epilog(submit); tx = NULL; } +out: + kfree(coefs); dmaengine_unmap_put(unmap); return tx; diff --git a/crypto/async_tx/raid6test.c b/crypto/async_tx/raid6test.c index dad95f45b88f..4237a5ae8f42 100644 --- a/crypto/async_tx/raid6test.c +++ b/crypto/async_tx/raid6test.c @@ -24,6 +24,7 @@ #include <linux/mm.h> #include <linux/random.h> #include <linux/module.h> +#include <linux/slab.h> #undef pr #define pr(fmt, args...) pr_info("raid6test: " fmt, ##args) @@ -81,11 +82,16 @@ 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; struct page *dest; int count = 0; int i; + blocks = kmalloc_array(disks, sizeof(*blocks), + GFP_KERNEL); + if (!blocks) + return; + /* data+Q failure. Reconstruct data from P, * then rebuild syndrome */ @@ -101,6 +107,7 @@ static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, stru init_async_submit(&submit, 0, tx, NULL, NULL, addr_conv); tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit); + kfree(blocks); } } else { if (failb == disks-2) { -- 2.17.0.441.gb46fe60e1d-goog
