summaryrefslogtreecommitdiffstats
path: root/drivers/tty
diff options
context:
space:
mode:
authorDan Williams <dan.j.williams@intel.com>2015-08-10 23:07:06 -0400
committerDan Williams <dan.j.williams@intel.com>2015-08-14 13:23:28 -0400
commit92281dee825f6d2eb07c441437e4196a44b0861c (patch)
tree2d8e24a39dfacf286ab66644545af853056d64f7 /drivers/tty
parent92b19ff50e8f242392d78b2aacc5b5b672f1796b (diff)
downloadlinux-92281dee825f6d2eb07c441437e4196a44b0861c.tar.bz2
arch: introduce memremap()
Existing users of ioremap_cache() are mapping memory that is known in advance to not have i/o side effects. These users are forced to cast away the __iomem annotation, or otherwise neglect to fix the sparse errors thrown when dereferencing pointers to this memory. Provide memremap() as a non __iomem annotated ioremap_*() in the case when ioremap is otherwise a pointer to cacheable memory. Empirically, ioremap_<cacheable-type>() call sites are seeking memory-like semantics (e.g. speculative reads, and prefetching permitted). memremap() is a break from the ioremap implementation pattern of adding a new memremap_<type>() for each mapping type and having silent compatibility fall backs. Instead, the implementation defines flags that are passed to the central memremap() and if a mapping type is not supported by an arch memremap returns NULL. We introduce a memremap prototype as a trivial wrapper of ioremap_cache() and ioremap_wt(). Later, once all ioremap_cache() and ioremap_wt() usage has been removed from drivers we teach archs to implement arch_memremap() with the ability to strictly enforce the mapping type. Cc: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/tty')
0 files changed, 0 insertions, 0 deletions