On Tue, 27 Jul 2021 at 12:06, Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> wrote: > > On Mon, Jul 26, 2021 at 05:55:33PM +0200, Ard Biesheuvel wrote: > > On Mon, 26 Jul 2021 at 12:00, Lorenzo Pieralisi > > <lorenzo.pieralisi@xxxxxxx> wrote: > > > > > > The memory attributes attached to memory regions depend on architecture > > > specific mappings. > > > > > > For some memory regions, the attributes specified by firmware (eg > > > uncached) are not sufficient to determine how a memory region should be > > > mapped by an OS (for instance a region that is define as uncached in > > > firmware can be mapped as Normal or Device memory on arm64) and > > > therefore the OS must be given control on how to map the region to match > > > the expected mapping behaviour (eg if a mapping is requested with memory > > > semantics, it must allow unaligned accesses). > > > > > > Rework acpi_os_map_memory() and acpi_os_ioremap() back-end to split > > > them into two separate code paths: > > > > > > acpi_os_memmap() -> memory semantics > > > acpi_os_ioremap() -> MMIO semantics > > > > > > The split allows the architectural implementation back-ends to detect > > > the default memory attributes required by the mapping in question > > > (ie the mapping API defines the semantics memory vs MMIO) and map the > > > memory accordingly. > > > > > > Link: https://lore.kernel.org/linux-arm-kernel/31ffe8fc-f5ee-2858-26c5-0fd8bdd68702@xxxxxxx > > > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> > > > Cc: Ard Biesheuvel <ardb@xxxxxxxxxx> > > > Cc: Will Deacon <will@xxxxxxxxxx> > > > Cc: Hanjun Guo <guohanjun@xxxxxxxxxx> > > > Cc: Sudeep Holla <sudeep.holla@xxxxxxx> > > > Cc: Catalin Marinas <catalin.marinas@xxxxxxx> > > > Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> > > > > For the patch in general > > > > Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx> > > Thanks ! > > [...] > > > > -void __iomem __ref > > > -*acpi_os_map_iomem(acpi_physical_address phys, acpi_size size) > > > +static void __iomem __ref > > > +*__acpi_os_map_iomem(acpi_physical_address phys, acpi_size size, bool memory) > > > { > > > struct acpi_ioremap *map; > > > void __iomem *virt; > > > @@ -353,7 +356,7 @@ void __iomem __ref > > > > > > pg_off = round_down(phys, PAGE_SIZE); > > > pg_sz = round_up(phys + size, PAGE_SIZE) - pg_off; > > > - virt = acpi_map(phys, size); > > > + virt = acpi_map(phys, size, memory); > > > if (!virt) { > > > mutex_unlock(&acpi_ioremap_lock); > > > kfree(map); > > > @@ -372,11 +375,17 @@ void __iomem __ref > > > mutex_unlock(&acpi_ioremap_lock); > > > return map->virt + (phys - map->phys); > > > } > > > + > > > +void __iomem __ref > > > +*acpi_os_map_iomem(acpi_physical_address phys, acpi_size size) > > > > I am aware that this just duplicated the prototype above, but I think > > this should be > > > > void __iomem *__ref > > > > given that the __ref comes after the * in the prototype below. > > Yes I just moved/duplicated the prototype above but I believe this is > consistent with include/acpi/acpi_io.h unless I have not understood > what you meant ? > > It is probably worth changing it in both places to > > void __iomem *__ref > > ? > > I can do that with an additional patch. > Yes, as long as they are all mutually consistent. The __ref is not part of the type at all, so it should not be between the void and the *, even if the compiler appears to allow it. > > > > > +{ > > > + return __acpi_os_map_iomem(phys, size, false); > > > +} > > > EXPORT_SYMBOL_GPL(acpi_os_map_iomem); > > > > > > void *__ref acpi_os_map_memory(acpi_physical_address phys, acpi_size size) > > > { > > > - return (void *)acpi_os_map_iomem(phys, size); > > > + return (void *)__acpi_os_map_iomem(phys, size, true); > > > > I think this should be (__force void *) to shut up sparse address > > space warnings. > > Yes I can add that attribute in an additional patch and rebase this one > on top of it. > > Thanks, > Lorenzo > > > > > > } > > > EXPORT_SYMBOL_GPL(acpi_os_map_memory); > > > > > > diff --git a/include/acpi/acpi_io.h b/include/acpi/acpi_io.h > > > index 027faa8883aa..a0212e67d6f4 100644 > > > --- a/include/acpi/acpi_io.h > > > +++ b/include/acpi/acpi_io.h > > > @@ -14,6 +14,14 @@ static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys, > > > } > > > #endif > > > > > > +#ifndef acpi_os_memmap > > > +static inline void __iomem *acpi_os_memmap(acpi_physical_address phys, > > > + acpi_size size) > > > +{ > > > + return ioremap_cache(phys, size); > > > +} > > > +#endif > > > + > > > extern bool acpi_permanent_mmap; > > > > > > void __iomem __ref > > > -- > > > 2.31.0 > > >
