FUJITA Tomonori d911202e3f uml: define CONFIG_NO_DMA ... I think that it's better to detect DMA misuse at build time rather than calling BUG_ON. Architectures that can't do DMA need to define CONFIG_NO_DMA. Thanks to Sam Ravnborg for explaining how CONFIG_NO_DMA and CONFIG_HAS_DMA work: http://marc.info/?l=linux-kernel&m=128359913825550&w=2 HAS_DMA is defined like this: config HAS_DMA boolean depends on !NO_DMA default y So to set HAS_DMA to true an arch should do: 1) Do not define NO_DMA 2) Define NO_DMA abd set it to 'n' Must archs - including um - used principle 1). In the um case we want to say that we do NOT have any DMA. This can be done in two ways. a) define NO_DMA and set it to 'y' b) redefine HAS_DMA and set it to 'n'. The patch you provided used principle b) where other archs use principle a). So I suggest you should use principle a) for um too. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Jeff Dike <jdike@addtoit.com> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2010-10-26 16:52:12 -07:00
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asm	uml: define CONFIG_NO_DMA	2010-10-26 16:52:12 -07:00
shared	Deal with missing exports for hostfs	2010-08-09 16:47:25 -04:00