[PATCH] drivers/dma/sirf-dma.c: fix usage of devm functions
From: Barry Song <hidden>
Date: 2012-08-04 23:53:52
Also in:
kernel-janitors, lkml
2012/8/4 Julia Lawall [off-list ref]
From: Julia Lawall <redacted> Fix some problems with the use of devm_ functions. devm_kzalloc: devm_kfree is not needed devm_ioremap: iounmap should not be used, no free is needed devm_request_irq: the devm_free_irq is followed by irq_dispose_mapping. I don't know if it is safe to move the freeing of the irq in this case, so I have just un-devm'd this function, since the implicit freeing is never taken advantage of. In the original code failure of of_address_to_resource jumped to free_mem, but should have jumped to irq_dispose, since irq_of_parse_and_map has completed at this point. In the original code unmap_mem was after irq_dispose, but it should have been before, again since irq_of_parse_and_map has completed at this point. One of these problems was found using the following semantic match: (http://coccinelle.lip6.fr/) // <smpl> @@ expression x; @@ *x = devm_ioremap(...) ... iounmap(x); // </smpl> Signed-off-by: Julia Lawall <redacted>
Acked-by: Barry Song <redacted> thanks!
quoted hunk ↗ jump to hunk
--- Not compiled. Does free_irq actually have to be called before irq_dispose_mapping? drivers/dma/sirf-dma.c | 23 +++++++---------------- 1 file changed, 7 insertions(+), 16 deletions(-)diff --git a/drivers/dma/sirf-dma.c b/drivers/dma/sirf-dma.c index 434ad31..1af9e48 100644 --- a/drivers/dma/sirf-dma.c +++ b/drivers/dma/sirf-dma.c@@ -570,21 +570,19 @@ static int __devinit sirfsoc_dma_probe(structplatform_device *op) if (of_property_read_u32(dn, "cell-index", &id)) { dev_err(dev, "Fail to get DMAC index\n"); - ret = -ENODEV; - goto free_mem; + return -ENODEV; } sdma->irq = irq_of_parse_and_map(dn, 0); if (sdma->irq == NO_IRQ) { dev_err(dev, "Error mapping IRQ!\n"); - ret = -EINVAL; - goto free_mem; + return -EINVAL; } ret = of_address_to_resource(dn, 0, &res); if (ret) { dev_err(dev, "Error parsing memory region!\n"); - goto free_mem; + goto irq_dispose; } regs_start = res.start;@@ -597,12 +595,11 @@ static int __devinit sirfsoc_dma_probe(structplatform_device *op) goto irq_dispose; } - ret = devm_request_irq(dev, sdma->irq, &sirfsoc_dma_irq, 0, DRV_NAME, - sdma); + ret = request_irq(sdma->irq, &sirfsoc_dma_irq, 0, DRV_NAME, sdma); if (ret) { dev_err(dev, "Error requesting IRQ!\n"); ret = -EINVAL; - goto unmap_mem; + goto irq_dispose; } dma = &sdma->dma;@@ -652,13 +649,9 @@ static int __devinit sirfsoc_dma_probe(structplatform_device *op) return 0; free_irq: - devm_free_irq(dev, sdma->irq, sdma); + free_irq(sdma->irq, sdma); irq_dispose: irq_dispose_mapping(sdma->irq); -unmap_mem: - iounmap(sdma->base); -free_mem: - devm_kfree(dev, sdma); return ret; }@@ -668,10 +661,8 @@ static int __devexit sirfsoc_dma_remove(structplatform_device *op) struct sirfsoc_dma *sdma = dev_get_drvdata(dev); dma_async_device_unregister(&sdma->dma); - devm_free_irq(dev, sdma->irq, sdma); + free_irq(sdma->irq, sdma); irq_dispose_mapping(sdma->irq); - iounmap(sdma->base); - devm_kfree(dev, sdma); return 0; }
-barry