[PATCH 6/7] SPARC64: SPARSEMEM_VMEMMAP support

Andy Whitcroft
2007-07-13T13:37:40Z

Hey Christoph, here is sparc64 support for this stuff.

After implementing this and seeing more and more how it works, I
really like it :-)

Thanks a lot for doing this work Christoph!

[apw@shadowen.org: style fixups]
From: David Miller <davem@davemloft.net>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Acked-by: Mel Gorman <mel@csn.ul.ie>
---
diff --git a/arch/sparc64/Kconfig b/arch/sparc64/Kconfig
index c73830d..9344dce 100644
--- a/arch/sparc64/Kconfig
+++ b/arch/sparc64/Kconfig
@@ -228,10 +228,17 @@ config ARCH_SPARSEMEM_ENABLE

config ARCH_SPARSEMEM_DEFAULT
def_bool y
- select SPARSEMEM_STATIC

source "mm/Kconfig"

+config SPARSEMEM_VMEMMAP
+ def_bool y
+ depends on SPARSEMEM
+
+config ARCH_POPULATES_SPARSEMEM_VMEMMAP
+ def_bool y
+ depends on SPARSEMEM_VMEMMAP
+
config ISA
bool
help
diff --git a/arch/sparc64/kernel/ktlb.S b/arch/sparc64/kernel/ktlb.S
index d4024ac..964527d 100644
--- a/arch/sparc64/kernel/ktlb.S
+++ b/arch/sparc64/kernel/ktlb.S
@@ -226,6 +226,15 @@ kvmap_dtlb_load:
ba,pt %xcc, sun4v_dtlb_load
mov %g5, %g3

+kvmap_vmemmap:
+ sub %g4, %g5, %g5
+ srlx %g5, 22, %g5
+ sethi %hi(vmemmap_table), %g1
+ sllx %g5, 3, %g5
+ or %g1, %lo(vmemmap_table), %g1
+ ba,pt %xcc, kvmap_dtlb_load
+ ldx [%g1 + %g5], %g5
+
kvmap_dtlb_nonlinear:
/* Catch kernel NULL pointer derefs. */
sethi %hi(PAGE_SIZE), %g5
@@ -233,6 +242,13 @@ kvmap_dtlb_nonlinear:
bleu,pn %xcc, kvmap_dtlb_longpath
nop

+ /* Do not use the TSB for vmemmap. */
+ mov (VMEMMAP_BASE >> 24), %g5
+ sllx %g5, 24, %g5
+ cmp %g4,%g5
+ bgeu,pn %xcc, kvmap_vmemmap
+ nop
+
KERN_TSB_LOOKUP_TL1(%g4, %g6, %g5, %g1, %g2, %g3, kvmap_dtlb_load)

kvmap_dtlb_tsbmiss:
diff --git a/arch/sparc64/mm/init.c b/arch/sparc64/mm/init.c
index 3010227..9bb6688 100644
--- a/arch/sparc64/mm/init.c
+++ b/arch/sparc64/mm/init.c
@@ -1647,6 +1647,58 @@ EXPORT_SYMBOL(_PAGE_E);
unsigned long _PAGE_CACHE __read_mostly;
EXPORT_SYMBOL(_PAGE_CACHE);

+#ifdef CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP
+
+#define VMEMMAP_CHUNK_SHIFT 22
+#define VMEMMAP_CHUNK (1UL << VMEMMAP_CHUNK_SHIFT)
+#define VMEMMAP_CHUNK_MASK ~(VMEMMAP_CHUNK - 1UL)
+#define VMEMMAP_ALIGN(x) (((x)+VMEMMAP_CHUNK-1UL)&VMEMMAP_CHUNK_MASK)
+
+#define VMEMMAP_SIZE ((((1UL << MAX_PHYSADDR_BITS) >> PAGE_SHIFT) * \
+ sizeof(struct page *)) >> VMEMMAP_CHUNK_SHIFT)
+unsigned long vmemmap_table[VMEMMAP_SIZE];
+
+int __meminit vmemmap_populate(struct page *start, unsigned long nr, int node)
+{
+ unsigned long vstart = (unsigned long) start;
+ unsigned long vend = (unsigned long) (start + nr);
+ unsigned long phys_start = (vstart - VMEMMAP_BASE);
+ unsigned long phys_end = (vend - VMEMMAP_BASE);
+ unsigned long addr = phys_start & VMEMMAP_CHUNK_MASK;
+ unsigned long end = VMEMMAP_ALIGN(phys_end);
+ unsigned long pte_base;
+
+ pte_base = (_PAGE_VALID | _PAGE_SZ4MB_4U |
+ _PAGE_CP_4U | _PAGE_CV_4U |
+ _PAGE_P_4U | _PAGE_W_4U);
+ if (tlb_type == hypervisor)
+ pte_base = (_PAGE_VALID | _PAGE_SZ4MB_4V |
+ _PAGE_CP_4V | _PAGE_CV_4V |
+ _PAGE_P_4V | _PAGE_W_4V);
+
+ for (; addr < end; addr += VMEMMAP_CHUNK) {
+ unsigned long *vmem_pp =
+ vmemmap_table + (addr >> VMEMMAP_CHUNK_SHIFT);
+ void *block;
+
+ if (!(*vmem_pp & _PAGE_VALID)) {
+ block = vmemmap_alloc_block(1UL << 22, node);
+ if (!block)
+ return -ENOMEM;
+
+ *vmem_pp = pte_base | __pa(block);
+
+ printk(KERN_INFO "[%p-%p] page_structs=%lu "
+ "node=%d entry=%lu/%lu\n", start, block, nr,
+ node,
+ addr >> VMEMMAP_CHUNK_SHIFT,
+ VMEMMAP_SIZE >> VMEMMAP_CHUNK_SHIFT);
+ }
+ }
+ return 0;
+}
+#endif /* CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP */
+
static void prot_init_common(unsigned long page_none,
unsigned long page_shared,
unsigned long page_copy,
diff --git a/include/asm-sparc64/pgtable.h b/include/asm-sparc64/pgtable.h
index 0393380..3167ccf 100644
--- a/include/asm-sparc64/pgtable.h
+++ b/include/asm-sparc64/pgtable.h
@@ -42,6 +42,9 @@
#define HI_OBP_ADDRESS _AC(0x0000000100000000,UL)
#define VMALLOC_START _AC(0x0000000100000000,UL)
#define VMALLOC_END _AC(0x0000000200000000,UL)
+#define VMEMMAP_BASE _AC(0x0000000200000000,UL)
+
+#define vmemmap ((struct page *)VMEMMAP_BASE)

/* XXX All of this needs to be rethought so we can take advantage
* XXX cheetah's full 64-bit virtual address space, ie. no more hole