On Wed, Apr 21, 2021 at 04:29:48PM +0530, Anshuman Khandual wrote: > > On 4/21/21 12:21 PM, Mike Rapoport wrote: > > From: Mike Rapoport <r...@linux.ibm.com> > > > > The intended semantics of pfn_valid() is to verify whether there is a > > struct page for the pfn in question and nothing else. > > > > Yet, on arm64 it is used to distinguish memory areas that are mapped in the > > linear map vs those that require ioremap() to access them. > > > > Introduce a dedicated pfn_is_map_memory() wrapper for > > memblock_is_map_memory() to perform such check and use it where > > appropriate. > > > > Using a wrapper allows to avoid cyclic include dependencies. > > > > Signed-off-by: Mike Rapoport <r...@linux.ibm.com> > > --- > > arch/arm64/include/asm/memory.h | 2 +- > > arch/arm64/include/asm/page.h | 1 + > > arch/arm64/kvm/mmu.c | 2 +- > > arch/arm64/mm/init.c | 11 +++++++++++ > > arch/arm64/mm/ioremap.c | 4 ++-- > > arch/arm64/mm/mmu.c | 2 +- > > 6 files changed, 17 insertions(+), 5 deletions(-) > > > > diff --git a/arch/arm64/include/asm/memory.h > > b/arch/arm64/include/asm/memory.h > > index 0aabc3be9a75..194f9f993d30 100644 > > --- a/arch/arm64/include/asm/memory.h > > +++ b/arch/arm64/include/asm/memory.h > > @@ -351,7 +351,7 @@ static inline void *phys_to_virt(phys_addr_t x) > > > > #define virt_addr_valid(addr) ({ > > \ > > __typeof__(addr) __addr = __tag_reset(addr); \ > > - __is_lm_address(__addr) && pfn_valid(virt_to_pfn(__addr)); \ > > + __is_lm_address(__addr) && pfn_is_map_memory(virt_to_pfn(__addr)); > > \ > > }) > > > > void dump_mem_limit(void); > > diff --git a/arch/arm64/include/asm/page.h b/arch/arm64/include/asm/page.h > > index 012cffc574e8..99a6da91f870 100644 > > --- a/arch/arm64/include/asm/page.h > > +++ b/arch/arm64/include/asm/page.h > > @@ -38,6 +38,7 @@ void copy_highpage(struct page *to, struct page *from); > > typedef struct page *pgtable_t; > > > > extern int pfn_valid(unsigned long); > > +extern int pfn_is_map_memory(unsigned long); > > Check patch is complaining about this. > > WARNING: function definition argument 'unsigned long' should also have an > identifier name > #50: FILE: arch/arm64/include/asm/page.h:41: > +extern int pfn_is_map_memory(unsigned long); > > > > > > #include <asm/memory.h> > > > > diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c > > index 8711894db8c2..23dd99e29b23 100644 > > --- a/arch/arm64/kvm/mmu.c > > +++ b/arch/arm64/kvm/mmu.c > > @@ -85,7 +85,7 @@ void kvm_flush_remote_tlbs(struct kvm *kvm) > > > > static bool kvm_is_device_pfn(unsigned long pfn) > > { > > - return !pfn_valid(pfn); > > + return !pfn_is_map_memory(pfn); > > } > > > > /* > > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c > > index 3685e12aba9b..dc03bdc12c0f 100644 > > --- a/arch/arm64/mm/init.c > > +++ b/arch/arm64/mm/init.c > > @@ -258,6 +258,17 @@ int pfn_valid(unsigned long pfn) > > } > > EXPORT_SYMBOL(pfn_valid); > > > > +int pfn_is_map_memory(unsigned long pfn) > > +{ > > + phys_addr_t addr = PFN_PHYS(pfn); > > + > > Should also bring with it, the comment regarding upper bits in > the pfn from arm64 pfn_valid().
I think a reference to the comment in pfn_valid() will suffice. BTW, I wonder how is that other architectures do not need this check? > > + if (PHYS_PFN(addr) != pfn) > > + return 0; > > + > > ^^^^^ trailing spaces here. > > ERROR: trailing whitespace > #81: FILE: arch/arm64/mm/init.c:263: > +^I$ Oops :) > > + return memblock_is_map_memory(addr); > > +} > > +EXPORT_SYMBOL(pfn_is_map_memory); > > + > > Is the EXPORT_SYMBOL() required to build drivers which will use > pfn_is_map_memory() but currently use pfn_valid() ? Yes, this is required for virt_addr_valid() that is used by modules. -- Sincerely yours, Mike. _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm