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author | Dmitry Kasatkin <dmitry.kasatkin@nokia.com> | 2011-06-02 21:10:06 +0300 |
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committer | Herbert Xu <herbert@gondor.apana.org.au> | 2011-06-30 07:44:02 +0800 |
commit | a929cbeef7d8e5c3603a6f43b977c03c922aada3 (patch) | |
tree | dd5321e7f54daf6eea76902523312a87ed56ad10 /drivers/crypto | |
parent | ea1fd2246f3c3c6b739529db2a547fa080cf09a3 (diff) | |
download | linux-a929cbeef7d8e5c3603a6f43b977c03c922aada3.tar.gz linux-a929cbeef7d8e5c3603a6f43b977c03c922aada3.tar.bz2 linux-a929cbeef7d8e5c3603a6f43b977c03c922aada3.zip |
crypto: omap-sham - replace flags operation with atomic bit operations
Some flags are changed in interrupt handlers and verified in the tasklet.
There might be a race condition when tasklet is interrupted or another
cpu/core will run IRQ handler and tasklet in parallel.
Atomic bitops functions are now used instead of bitmask operations.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/crypto')
-rw-r--r-- | drivers/crypto/omap-sham.c | 29 |
1 files changed, 13 insertions, 16 deletions
diff --git a/drivers/crypto/omap-sham.c b/drivers/crypto/omap-sham.c index 64698adec0c1..208404e20ef7 100644 --- a/drivers/crypto/omap-sham.c +++ b/drivers/crypto/omap-sham.c @@ -240,7 +240,7 @@ static int omap_sham_hw_init(struct omap_sham_dev *dd) { clk_enable(dd->iclk); - if (!(dd->flags & BIT(FLAGS_INIT))) { + if (!test_bit(FLAGS_INIT, &dd->flags)) { omap_sham_write_mask(dd, SHA_REG_MASK, SHA_REG_MASK_SOFTRESET, SHA_REG_MASK_SOFTRESET); @@ -248,7 +248,7 @@ static int omap_sham_hw_init(struct omap_sham_dev *dd) SHA_REG_SYSSTATUS_RESETDONE)) return -ETIMEDOUT; - dd->flags |= BIT(FLAGS_INIT); + set_bit(FLAGS_INIT, &dd->flags); dd->err = 0; } @@ -303,7 +303,7 @@ static int omap_sham_xmit_cpu(struct omap_sham_dev *dd, const u8 *buf, return -ETIMEDOUT; if (final) - ctx->flags |= BIT(FLAGS_FINAL); /* catch last interrupt */ + set_bit(FLAGS_FINAL, &ctx->flags); /* catch last interrupt */ len32 = DIV_ROUND_UP(length, sizeof(u32)); @@ -336,9 +336,9 @@ static int omap_sham_xmit_dma(struct omap_sham_dev *dd, dma_addr_t dma_addr, ctx->digcnt += length; if (final) - ctx->flags |= BIT(FLAGS_FINAL); /* catch last interrupt */ + set_bit(FLAGS_FINAL, &ctx->flags); /* catch last interrupt */ - dd->flags |= BIT(FLAGS_DMA_ACTIVE); + set_bit(FLAGS_DMA_ACTIVE, &dd->flags); omap_start_dma(dd->dma_lch); @@ -642,7 +642,7 @@ static void omap_sham_finish_req(struct ahash_request *req, int err) if (!err) { omap_sham_copy_hash(req, 1); - if (ctx->flags & BIT(FLAGS_FINAL)) + if (test_bit(FLAGS_FINAL, &ctx->flags)) err = omap_sham_finish(req); } else { ctx->flags |= BIT(FLAGS_ERROR); @@ -666,14 +666,14 @@ static int omap_sham_handle_queue(struct omap_sham_dev *dd, spin_lock_irqsave(&dd->lock, flags); if (req) ret = ahash_enqueue_request(&dd->queue, req); - if (dd->flags & BIT(FLAGS_BUSY)) { + if (test_bit(FLAGS_BUSY, &dd->flags)) { spin_unlock_irqrestore(&dd->lock, flags); return ret; } backlog = crypto_get_backlog(&dd->queue); async_req = crypto_dequeue_request(&dd->queue); if (async_req) - dd->flags |= BIT(FLAGS_BUSY); + set_bit(FLAGS_BUSY, &dd->flags); spin_unlock_irqrestore(&dd->lock, flags); if (!async_req) @@ -1037,13 +1037,10 @@ static void omap_sham_done_task(unsigned long data) struct omap_sham_reqctx *ctx = ahash_request_ctx(req); int ready = 0, err = 0; - if (ctx->flags & BIT(FLAGS_OUTPUT_READY)) { - ctx->flags &= ~BIT(FLAGS_OUTPUT_READY); + if (test_and_clear_bit(FLAGS_OUTPUT_READY, &ctx->flags)) ready = 1; - } - if (dd->flags & BIT(FLAGS_DMA_ACTIVE)) { - dd->flags &= ~BIT(FLAGS_DMA_ACTIVE); + if (test_and_clear_bit(FLAGS_DMA_ACTIVE, &dd->flags)) { omap_sham_update_dma_stop(dd); if (!dd->err) err = omap_sham_update_dma_start(dd); @@ -1077,7 +1074,7 @@ static irqreturn_t omap_sham_irq(int irq, void *dev_id) return IRQ_HANDLED; } - if (unlikely(ctx->flags & BIT(FLAGS_FINAL))) + if (unlikely(test_bit(FLAGS_FINAL, &ctx->flags))) /* final -> allow device to go to power-saving mode */ omap_sham_write_mask(dd, SHA_REG_CTRL, 0, SHA_REG_CTRL_LENGTH); @@ -1085,7 +1082,7 @@ static irqreturn_t omap_sham_irq(int irq, void *dev_id) SHA_REG_CTRL_OUTPUT_READY); omap_sham_read(dd, SHA_REG_CTRL); - ctx->flags |= BIT(FLAGS_OUTPUT_READY); + set_bit(FLAGS_OUTPUT_READY, &ctx->flags); dd->err = 0; tasklet_schedule(&dd->done_task); @@ -1099,7 +1096,7 @@ static void omap_sham_dma_callback(int lch, u16 ch_status, void *data) if (ch_status != OMAP_DMA_BLOCK_IRQ) { pr_err("omap-sham DMA error status: 0x%hx\n", ch_status); dd->err = -EIO; - dd->flags &= ~BIT(FLAGS_INIT); /* request to re-initialize */ + clear_bit(FLAGS_INIT, &dd->flags);/* request to re-initialize */ } tasklet_schedule(&dd->done_task); |