[PATCH] check for allocation failure in ioat_dma_self_test

[Andrew Cooks <acooks@gmail.com>]

This patch fixes a warning in ioat_dma_self_test when DMA_API_DEBUG is enabled. The warning is:

[    1.581984] ioatdma: Intel(R) QuickData Technology Driver 4.00
[    1.582095] bus: 'pci': add driver ioatdma
[    1.582102] bus: 'pci': driver_probe_device: matched device 0000:00:04.0 with driver ioatdma
[    1.582104] bus: 'pci': really_probe: probing driver ioatdma with device 0000:00:04.0
[    1.582175] ioatdma 0000:00:04.0: can't derive routing for PCI INT A
[    1.582281] ioatdma 0000:00:04.0: PCI INT A: no GSI
[    1.582552] ioatdma 0000:00:04.0: irq 52 for MSI/MSI-X
[    1.582631] Set context mapping for 00:04.0
[    1.582920] ------------[ cut here ]------------
[    1.583027] WARNING: at lib/dma-debug.c:933 check_unmap+0x645/0x6f1()
[    1.583132] Hardware name: To be filled by O.E.M.
[    1.583236] ioatdma 0000:00:04.0: DMA-API: device driver failed to check map error[device address=0x00000000ffff9800] [size=2000 bytes] [mapped as single]
[    1.583237] Modules linked in:
[    1.583240] Pid: 1, comm: swapper/0 Not tainted 3.9.0-rc1-dirty #248
[    1.583241] Call Trace:
[    1.583244]  [<ffffffff8103d98e>] warn_slowpath_common+0x85/0x9f
[    1.583246]  [<ffffffff8103da4b>] warn_slowpath_fmt+0x46/0x48
[    1.583248]  [<ffffffff81257a7b>] check_unmap+0x645/0x6f1
[    1.583251]  [<ffffffff81505e10>] ? _raw_spin_unlock_irqrestore+0x3f/0x55
[    1.583253]  [<ffffffff81257d07>] debug_dma_unmap_page+0x59/0x5b
[    1.583256]  [<ffffffff812ea925>] dma_unmap_single_attrs.clone.2+0x6a/0x73
[    1.583258]  [<ffffffff812eb3b7>] ioat_dma_self_test+0x228/0x29d
[    1.583260]  [<ffffffff8150449a>] ? __wait_for_common+0xe7/0x15a
[    1.583263]  [<ffffffff812ef74d>] ioat3_dma_self_test+0x16/0x29
[    1.583264]  [<ffffffff812e9be9>] ioat_probe+0xbc/0xea
[    1.583266]  [<ffffffff812ed1fb>] ioat3_dma_probe+0x1d3/0x275
[    1.583268]  [<ffffffff812e9135>] ioat_pci_probe+0x14d/0x178
[    1.583271]  [<ffffffff812650a7>] local_pci_probe+0x3e/0x66
[    1.583273]  [<ffffffff81265179>] __pci_device_probe+0xaa/0xc3
[    1.583275]  [<ffffffff8131fce7>] ? get_device+0x19/0x1f
[    1.583277]  [<ffffffff81265c06>] pci_device_probe+0x35/0x50
[    1.583280]  [<ffffffff81323960>] really_probe+0xda/0x29c
[    1.583282]  [<ffffffff8132e2dd>] ? pm_runtime_barrier+0x70/0x99
[    1.583284]  [<ffffffff81323b96>] driver_probe_device+0x74/0x8d
[    1.583286]  [<ffffffff81323c10>] __driver_attach+0x61/0x85
[    1.583288]  [<ffffffff81323baf>] ? driver_probe_device+0x8d/0x8d
[    1.583289]  [<ffffffff81323baf>] ? driver_probe_device+0x8d/0x8d
[    1.583291]  [<ffffffff81321f3a>] bus_for_each_dev+0x58/0x96
[    1.583293]  [<ffffffff813236d5>] driver_attach+0x1e/0x20
[    1.583295]  [<ffffffff813230ba>] bus_add_driver+0xed/0x223
[    1.583298]  [<ffffffff81ce06b9>] ? dma_bus_init+0x19/0x19
[    1.583300]  [<ffffffff813241f0>] driver_register+0x8f/0x108
[    1.583301]  [<ffffffff81ce06b9>] ? dma_bus_init+0x19/0x19
[    1.583303]  [<ffffffff81265d10>] __pci_register_driver+0x64/0x68
[    1.583305]  [<ffffffff81ce0721>] ioat_init_module+0x68/0x80
[    1.583307]  [<ffffffff81cdf92e>] ? setup_erst_disable+0x12/0x12
[    1.583310]  [<ffffffff81000237>] do_one_initcall+0x7f/0x133
[    1.583312]  [<ffffffff81cb27a6>] do_basic_setup+0x9c/0xba
[    1.583314]  [<ffffffff81cb28f0>] ? kernel_init_freeable+0x12c/0x12c
[    1.583316]  [<ffffffff81cb2877>] kernel_init_freeable+0xb3/0x12c
[    1.583318]  [<ffffffff814f7324>] ? rest_init+0xd8/0xd8
[    1.583320]  [<ffffffff814f7332>] kernel_init+0xe/0xdb
[    1.583322]  [<ffffffff8150d4dc>] ret_from_fork+0x7c/0xb0
[    1.583324]  [<ffffffff814f7324>] ? rest_init+0xd8/0xd8
[    1.583340] ---[ end trace a5a9423f147d46b4 ]---
[    1.583443] Mapped at:
[    1.583545]  [<ffffffff81258192>] debug_dma_map_page+0x4c/0xec
[    1.583547]  [<ffffffff812ea8a8>] dma_map_single_attrs.clone.1+0xe3/0xf6
[    1.583549]  [<ffffffff812eb260>] ioat_dma_self_test+0xd1/0x29d
[    1.583550]  [<ffffffff812ef74d>] ioat3_dma_self_test+0x16/0x29
[    1.583552]  [<ffffffff812e9be9>] ioat_probe+0xbc/0xea


Applies to 3.9-rc1

Signed-off-by: Andrew Cooks <acooks@gmail.com>
---
 drivers/dma/ioat/dma.c |   11 +++++++++++
 1 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c
index 1879a59..1f706c4 100644
--- a/drivers/dma/ioat/dma.c
+++ b/drivers/dma/ioat/dma.c
@@ -832,7 +832,18 @@ int ioat_dma_self_test(struct ioatdma_device *device)
 	}
 
 	dma_src = dma_map_single(dev, src, IOAT_TEST_SIZE, DMA_TO_DEVICE);
+	err = dma_mapping_error(dev, dma_src);
+	if (err) {
+		dev_err(dev, "dma mapping failed: -%d\n", err);
+		goto free_resources;
+	}
 	dma_dest = dma_map_single(dev, dest, IOAT_TEST_SIZE, DMA_FROM_DEVICE);
+	err = dma_mapping_error(dev, dma_dest);
+	if (err) {
+		dev_err(dev, "dma mapping failed: -%d\n", err);
+		dma_unmap_single(dev, dma_src, IOAT_TEST_SIZE, DMA_TO_DEVICE);
+		goto free_resources;
+	}
 	flags = DMA_COMPL_SKIP_SRC_UNMAP | DMA_COMPL_SKIP_DEST_UNMAP |
 		DMA_PREP_INTERRUPT;
 	tx = device->common.device_prep_dma_memcpy(dma_chan, dma_dest, dma_src,
-- 
1.7.1