| Message ID | 20190327213643.23789-5-logang@deltatee.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | RISC-V: Sparsmem, Memory Hotplug and pte_devmap for P2P | expand |
On Thu, Mar 28, 2019 at 3:06 AM Logan Gunthorpe <logang@deltatee.com> wrote: > > With the new virtual address changes in an earlier patch, we want the > page tables to cover more of the linear mapping region. Instead of > only mapping from PAGE_OFFSET and up, we instead map starting > from an aligned version of va_pa_offset such that all of the physical > address space will be mapped. > > Signed-off-by: Logan Gunthorpe <logang@deltatee.com> > Cc: Palmer Dabbelt <palmer@sifive.com> > Cc: Albert Ou <aou@eecs.berkeley.edu> > Cc: Anup Patel <anup.patel@wdc.com> > Cc: Atish Patra <atish.patra@wdc.com> > Cc: Paul Walmsley <paul.walmsley@sifive.com> > Cc: Zong Li <zongbox@gmail.com> > Cc: Mike Rapoport <rppt@linux.ibm.com> > --- > arch/riscv/kernel/setup.c | 1 - > arch/riscv/mm/init.c | 27 +++++++++++++++------------ > 2 files changed, 15 insertions(+), 13 deletions(-) > > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c > index ecb654f6a79e..8286df8be31a 100644 > --- a/arch/riscv/kernel/setup.c > +++ b/arch/riscv/kernel/setup.c > @@ -59,7 +59,6 @@ EXPORT_SYMBOL(empty_zero_page); > /* The lucky hart to first increment this variable will boot the other cores */ > atomic_t hart_lottery; > unsigned long boot_cpu_hartid; > - > void __init parse_dtb(unsigned int hartid, void *dtb) > { > if (early_init_dt_scan(__va(dtb))) > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > index b9d50031e78f..315194557c3d 100644 > --- a/arch/riscv/mm/init.c > +++ b/arch/riscv/mm/init.c > @@ -150,8 +150,8 @@ pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss; > pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); > > #ifndef __PAGETABLE_PMD_FOLDED > -#define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT) > -pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss; > +#define NUM_SWAPPER_PMDS ((uintptr_t)-VMALLOC_END >> PGDIR_SHIFT) > +pmd_t swapper_pmd[PTRS_PER_PMD*((-VMALLOC_END)/PGDIR_SIZE)] __page_aligned_bss; > pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); > pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss; > #endif > @@ -180,13 +180,18 @@ asmlinkage void __init setup_vm(void) > extern char _start; > uintptr_t i; > uintptr_t pa = (uintptr_t) &_start; > + uintptr_t linear_start; > + uintptr_t off; > pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_EXEC); > > va_pa_offset = PAGE_OFFSET - pa; > pfn_base = PFN_DOWN(pa); > > + linear_start = ALIGN_DOWN(va_pa_offset, PGDIR_SIZE); > + off = linear_start - va_pa_offset; > + > /* Sanity check alignment and size */ > - BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); > + BUG_ON(linear_start <= VMALLOC_END); > BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0); > > #ifndef __PAGETABLE_PMD_FOLDED > @@ -195,15 +200,14 @@ asmlinkage void __init setup_vm(void) > __pgprot(_PAGE_TABLE)); > trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot); > > - for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) { > - size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i; > - > + for (i = 0; i < (-linear_start)/PGDIR_SIZE; ++i) { > + size_t o = (linear_start >> PGDIR_SHIFT) % PTRS_PER_PGD + i; > swapper_pg_dir[o] = > pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i, > __pgprot(_PAGE_TABLE)); > } > for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++) > - swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot); > + swapper_pmd[i] = pfn_pmd(PFN_DOWN(off + i * PMD_SIZE), prot); > > swapper_pg_dir[(FIXADDR_START >> PGDIR_SHIFT) % PTRS_PER_PGD] = > pfn_pgd(PFN_DOWN((uintptr_t)fixmap_pmd), > @@ -215,11 +219,10 @@ asmlinkage void __init setup_vm(void) > trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] = > pfn_pgd(PFN_DOWN(pa), prot); > > - for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) { > - size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i; > - > - swapper_pg_dir[o] = > - pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot); > + for (i = 0; i < (-linear_start)/PGDIR_SIZE; ++i) { > + size_t o = (linear_start >> PGDIR_SHIFT) % PTRS_PER_PGD + i; > + swapper_pg_dir[o] = pfn_pgd(PFN_DOWN(off + i * PGDIR_SIZE), > + prot); > } > > swapper_pg_dir[(FIXADDR_START >> PGDIR_SHIFT) % PTRS_PER_PGD] = > -- > 2.20.1 > I understand that this patch is inline with your virtual memory layout cleanup but the way we map virtual memory in swapper_pg_dir is bound to change. We should not be mapping complete virtual memory in swapper_pd_dir() rather we should only map based on amount of RAM available. Refer, https://www.lkml.org/lkml/2019/3/24/3 The setup_vm() should only map vmlinux_start to vmlinux_end plus the FDT. Complete virtual memory mapping should be done after we have done early parsing of FDT when we know available memory banks in setup_vm_final() (called from paging_init()) Regards, Anup
On 2019-03-28 4:03 a.m., Anup Patel wrote: > I understand that this patch is inline with your virtual memory layout cleanup > but the way we map virtual memory in swapper_pg_dir is bound to change. > > We should not be mapping complete virtual memory in swapper_pd_dir() > rather we should only map based on amount of RAM available. > > Refer, https://www.lkml.org/lkml/2019/3/24/3 > > The setup_vm() should only map vmlinux_start to vmlinux_end plus the > FDT. Complete virtual memory mapping should be done after we have > done early parsing of FDT when we know available memory banks in > setup_vm_final() (called from paging_init()) That makes sense, but I think a lot of it sounds a out of the scope of what I'm doing in this patch set. I could attempt to update my patchset so instead of expanding the linear region on boot, we add the page tables in arch_add_memory. That would make more sense when considering the direction you want to head with setup_vm. Logan
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index ecb654f6a79e..8286df8be31a 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -59,7 +59,6 @@ EXPORT_SYMBOL(empty_zero_page); /* The lucky hart to first increment this variable will boot the other cores */ atomic_t hart_lottery; unsigned long boot_cpu_hartid; - void __init parse_dtb(unsigned int hartid, void *dtb) { if (early_init_dt_scan(__va(dtb))) diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index b9d50031e78f..315194557c3d 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -150,8 +150,8 @@ pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss; pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); #ifndef __PAGETABLE_PMD_FOLDED -#define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT) -pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss; +#define NUM_SWAPPER_PMDS ((uintptr_t)-VMALLOC_END >> PGDIR_SHIFT) +pmd_t swapper_pmd[PTRS_PER_PMD*((-VMALLOC_END)/PGDIR_SIZE)] __page_aligned_bss; pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss; #endif @@ -180,13 +180,18 @@ asmlinkage void __init setup_vm(void) extern char _start; uintptr_t i; uintptr_t pa = (uintptr_t) &_start; + uintptr_t linear_start; + uintptr_t off; pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_EXEC); va_pa_offset = PAGE_OFFSET - pa; pfn_base = PFN_DOWN(pa); + linear_start = ALIGN_DOWN(va_pa_offset, PGDIR_SIZE); + off = linear_start - va_pa_offset; + /* Sanity check alignment and size */ - BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); + BUG_ON(linear_start <= VMALLOC_END); BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0); #ifndef __PAGETABLE_PMD_FOLDED @@ -195,15 +200,14 @@ asmlinkage void __init setup_vm(void) __pgprot(_PAGE_TABLE)); trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot); - for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) { - size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i; - + for (i = 0; i < (-linear_start)/PGDIR_SIZE; ++i) { + size_t o = (linear_start >> PGDIR_SHIFT) % PTRS_PER_PGD + i; swapper_pg_dir[o] = pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i, __pgprot(_PAGE_TABLE)); } for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++) - swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot); + swapper_pmd[i] = pfn_pmd(PFN_DOWN(off + i * PMD_SIZE), prot); swapper_pg_dir[(FIXADDR_START >> PGDIR_SHIFT) % PTRS_PER_PGD] = pfn_pgd(PFN_DOWN((uintptr_t)fixmap_pmd), @@ -215,11 +219,10 @@ asmlinkage void __init setup_vm(void) trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] = pfn_pgd(PFN_DOWN(pa), prot); - for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) { - size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i; - - swapper_pg_dir[o] = - pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot); + for (i = 0; i < (-linear_start)/PGDIR_SIZE; ++i) { + size_t o = (linear_start >> PGDIR_SHIFT) % PTRS_PER_PGD + i; + swapper_pg_dir[o] = pfn_pgd(PFN_DOWN(off + i * PGDIR_SIZE), + prot); } swapper_pg_dir[(FIXADDR_START >> PGDIR_SHIFT) % PTRS_PER_PGD] =
With the new virtual address changes in an earlier patch, we want the page tables to cover more of the linear mapping region. Instead of only mapping from PAGE_OFFSET and up, we instead map starting from an aligned version of va_pa_offset such that all of the physical address space will be mapped. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Anup Patel <anup.patel@wdc.com> Cc: Atish Patra <atish.patra@wdc.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Zong Li <zongbox@gmail.com> Cc: Mike Rapoport <rppt@linux.ibm.com> --- arch/riscv/kernel/setup.c | 1 - arch/riscv/mm/init.c | 27 +++++++++++++++------------ 2 files changed, 15 insertions(+), 13 deletions(-)