| Message ID | 20150720001817.30857.69287.stgit@dwillia2-desk3.amr.corp.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sun, Jul 19, 2015 at 08:18:17PM -0400, Dan Williams wrote: > In preparation for enabling memremap(), add support for strict mappings. > strict_ioremap_<type>() returns NULL if the arch does not implement the > mapping type, rather than falling back silently to ioremap(). Please don't introduce another large number of ioremap variants. I think we should go straight to the ioremap_flags variant, although I wonder if we should even bother with ioremap_flags for this use case, given that we really want memremap-like semantics for anything that isn't plain ioremap (and maybe ioremap_nocache). Sorry or being the downer, but I really think we need to clean up this mess deeply insted of trying to paper over it.
On Tue, Jul 21, 2015 at 6:30 AM, Christoph Hellwig <hch@lst.de> wrote: > On Sun, Jul 19, 2015 at 08:18:17PM -0400, Dan Williams wrote: >> In preparation for enabling memremap(), add support for strict mappings. >> strict_ioremap_<type>() returns NULL if the arch does not implement the >> mapping type, rather than falling back silently to ioremap(). > > Please don't introduce another large number of ioremap variants. > > I think we should go straight to the ioremap_flags variant, although > I wonder if we should even bother with ioremap_flags for this use > case, given that we really want memremap-like semantics for anything > that isn't plain ioremap (and maybe ioremap_nocache). > > Sorry or being the downer, but I really think we need to clean up this > mess deeply insted of trying to paper over it. No worries. I'll rework the series around the idea that memremap() is a replacement rather than a wrapper for ioremap_<type>().
diff --git a/include/linux/io.h b/include/linux/io.h index 58482241c95c..080a4fbf2ba4 100644 --- a/include/linux/io.h +++ b/include/linux/io.h @@ -130,6 +130,27 @@ static inline void __iomem *ioremap_uc(resource_size_t offset, } #endif +static inline void __iomem *strict_ioremap_cache(resource_size_t offset, + unsigned long size) +{ +#ifdef ioremap_cache + return ioremap_cache(offset, size); +#else + return (void __force __iomem *) NULL; +#endif +} + +static inline void __iomem *strict_ioremap_wt(resource_size_t offset, + unsigned long size) +{ +#ifdef ioremap_wt + return ioremap_wt(offset, size); +#else + return (void __force __iomem *) NULL; +#endif +} + + /* * Some systems do not have legacy ISA devices. * /dev/port is not a valid interface on these systems.
In preparation for enabling memremap(), add support for strict mappings. strict_ioremap_<type>() returns NULL if the arch does not implement the mapping type, rather than falling back silently to ioremap(). Signed-off-by: Dan Williams <dan.j.williams@intel.com> --- include/linux/io.h | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+)