]> git.baikalelectronics.ru Git - kernel.git/commit
Fix iwlan DMA mapping direction
authorFenghua Yu <fenghua.yu@intel.com>
Wed, 25 Feb 2009 05:06:26 +0000 (14:06 +0900)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 25 Feb 2009 17:30:56 +0000 (09:30 -0800)
commit35f36ea36b58e3870f48e94251c159e0fa92f1dc
treea3575e24836180935611515a3610b59b3a642982
parent813a2cc98dadadf868f318b7f393703b67be76f9
Fix iwlan DMA mapping direction

When iwlan runs on IOMMU, IOMMU generates a lot of PTE write faults
because PTE write bit is not set on some of PTE's.  This is because
iwlan driver calls DMA mapping with PCI_DMA_TODEVICE which is read only
in mapping PTE.  But iwlan device actually writes to the mapped page to
update its contents.  This issue is not exposed in swiotlb.  But VT-d
hardware can capture this fault and stop the fault transaction.

The following patch fixes the issue.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Bhavesh Davda <bhavesh@vmware.com>
Tested-by: Chris Wright <chrisw@sous-sol.org>
Acked-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/net/wireless/iwlwifi/iwl-tx.c