Smita Koralahalli wrote: > From: Dan Williams <[email protected]> > > Insert Soft Reserved memory into a dedicated soft_reserve_resource tree > instead of the iomem_resource tree at boot. Delay publishing these ranges > into the iomem hierarchy until ownership is resolved and the HMEM path > is ready to consume them. > > Publishing Soft Reserved ranges into iomem too early conflicts with CXL > hotplug and prevents region assembly when those ranges overlap CXL > windows. > > Follow up patches will reinsert Soft Reserved ranges into iomem after CXL > window publication is complete and HMEM is ready to claim the memory. This > provides a cleaner handoff between EFI-defined memory ranges and CXL > resource management without trimming or deleting resources later.
Please, when you modify a patch from an original, add your Co-developed-by: and clarify what you changed. > > Signed-off-by: Dan Williams <[email protected]> > Signed-off-by: Smita Koralahalli <[email protected]> > --- > arch/x86/kernel/e820.c | 2 +- > drivers/cxl/acpi.c | 2 +- > drivers/dax/hmem/device.c | 4 +- > drivers/dax/hmem/hmem.c | 7 ++- > include/linux/ioport.h | 13 +++++- > kernel/resource.c | 92 +++++++++++++++++++++++++++++++++------ > 6 files changed, 100 insertions(+), 20 deletions(-) > [..] > @@ -426,6 +443,26 @@ int walk_iomem_res_desc(unsigned long desc, unsigned > long flags, u64 start, > } > EXPORT_SYMBOL_GPL(walk_iomem_res_desc); > > +#ifdef CONFIG_EFI_SOFT_RESERVE > +struct resource soft_reserve_resource = { > + .name = "Soft Reserved", > + .start = 0, > + .end = -1, > + .desc = IORES_DESC_SOFT_RESERVED, > + .flags = IORESOURCE_MEM, > +}; > +EXPORT_SYMBOL_GPL(soft_reserve_resource); It looks like one of the things you changed from my RFC was the addition of walk_soft_reserve_res_desc() and region_intersects_soft_reserve(). With those APIs not only does this symbol not need to be exported, but it also can be static / private to resource.c. > + > +int walk_soft_reserve_res_desc(unsigned long desc, unsigned long flags, > + u64 start, u64 end, void *arg, > + int (*func)(struct resource *, void *)) > +{ > + return walk_res_desc(&soft_reserve_resource, start, end, flags, desc, > + arg, func); > +} > +EXPORT_SYMBOL_GPL(walk_soft_reserve_res_desc); > +#endif > + > /* > * This function calls the @func callback against all memory ranges of type > * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY. > @@ -648,6 +685,22 @@ int region_intersects(resource_size_t start, size_t > size, unsigned long flags, > } > EXPORT_SYMBOL_GPL(region_intersects); > > +#ifdef CONFIG_EFI_SOFT_RESERVE > +int region_intersects_soft_reserve(resource_size_t start, size_t size, > + unsigned long flags, unsigned long desc) > +{ > + int ret; > + > + read_lock(&resource_lock); > + ret = __region_intersects(&soft_reserve_resource, start, size, flags, > + desc); > + read_unlock(&resource_lock); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(region_intersects_soft_reserve); > +#endif > + > void __weak arch_remove_reservations(struct resource *avail) > { > } > @@ -966,7 +1019,7 @@ EXPORT_SYMBOL_GPL(insert_resource); > * Insert a resource into the resource tree, possibly expanding it in order > * to make it encompass any conflicting resources. > */ > -void insert_resource_expand_to_fit(struct resource *root, struct resource > *new) > +void __insert_resource_expand_to_fit(struct resource *root, struct resource > *new) > { > if (new->parent) > return; > @@ -997,7 +1050,20 @@ void insert_resource_expand_to_fit(struct resource > *root, struct resource *new) > * to use this interface. The former are built-in and only the latter, > * CXL, is a module. > */ > -EXPORT_SYMBOL_NS_GPL(insert_resource_expand_to_fit, "CXL"); > +EXPORT_SYMBOL_NS_GPL(__insert_resource_expand_to_fit, "CXL"); > + > +void insert_resource_expand_to_fit(struct resource *new) > +{ > + struct resource *root = &iomem_resource; > + > +#ifdef CONFIG_EFI_SOFT_RESERVE > + if (new->desc == IORES_DESC_SOFT_RESERVED) > + root = &soft_reserve_resource; > +#endif I can not say I am entirely happy with this change, I would prefer to avoid ifdef in C, and I would prefer not to break the legacy semantics of this function, but it meets the spirit of the original RFC without introducing a new insert_resource_late(). I assume review feedback requested this? > + __insert_resource_expand_to_fit(root, new); > +} > +EXPORT_SYMBOL_GPL(insert_resource_expand_to_fit); There are no consumers for this export, so it can be dropped.
